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The study of systems whose properties are governed by electronic correlations is a corner stone of modern solid-state physics. Often, such systems feature unique and distinct properties like Mott metal-insulator transitions, rich phase diagrams, and high sensitivity to subtle changes in the applied conditions. Whereas the standard approach to electronic structure calculations, density functional theory (DFT), is able to address the complexity of real-world materials but is known to have serious limitations in the description of correlations, the dynamical mean-field theory (DMFT) has become an established method for the treatment of correlated fermions, first on the level of minimal models and later in combination with DFT, termed LDA+DMFT.
This thesis presents theoretical calculations on different materials exhibiting correlated physics, where we aim at covering a range in terms of systems --from rather weakly correlated to strongy correlated-- as well as in terms of methods, from DFT calculations to combined LDA+DMFT calculations. We begin with a study on a selection of iron pnictides, a recently discovered family of high-temperature superconductors with varying degree of correlation strength, and show that their magnetic and optical properties can be assessed to some degree within DFT, despite the correlated nature of these systems. Next, extending our analysis to the inclusion of correlations in the framework of LDA+DMFT, we discuss the electronic structure of the iron pnictide LiFeAs which we find to be well described by Fermi liquid theory with regard to many of its properties, yet we see distinct changes in its Fermi surface upon inclusion of correlations. We continue the study of low-energy properties and specifically Fermi surfaces on two more iron pnictides, LaFePO and LiFeP, and predict a topology change of their Fermi surfaces due to the effect of correlations, with possible implications for their superconducting properties. In our last study, we close the circle by presenting LDA+DMFT calculations on an organic molecular crystal on the verge of a Mott metal-insulator transition; there, we find the spectral and optical properties to display signatures of strong electronic correlations beyond Fermi liquid theory.
While the general elections in Myanmar in November 2010 were widely condemned, both national and international actors approached the by-elections of April 2012 as a political rite-de-passage to improve relations between the government and the opposition inside, and between the former pariah state and the international community outside the country. An undercurrent to the government-led transition process from an authoritarian to a formally more democratic regime was the development of a politically oriented civil society that found ways to engage in the electoral process. This article describes the emerging spaces of election-related civil society activism in the forms of civic and voter education, national election observation, and election-related agency in the media. Noting that, in particular, election observation offers connections for civil society to regional and international debates, the paper draws preliminary conclusions about further developments ahead of the general elections in Myanmar expected for 2015.
New technologies generate risks, for the evaluation of which various mechanisms have been developed; the most frequent of these mechanisms consists of advice from committees of experts to the bodies whose role is to decide whether a new technology should be implemented or not. Such committees try to measure the magnitude of the threats that accompany the introduction of a new technology in order that the policy-makers may take their decisions in the light of the reports of the experts. The legitimacy of such reports is not only found in the technical capacity of its authors, but also in the impartiality of their recommendations. On numerous occasions, nevertheless, the effective presence of this evaluation finds itself today under suspicion. There are various methods that can be employed to try to resolve this problem. Firstly by reinforcing the mechanisms on which the technocratic evaluation of the risk are based; for example, through transparency in the selection of the experts. Secondly, by means of the incorporation of democratic mechanisms in the scientific-technological policy. The exposure of the internal conditions to the dynamics of the technological change that make possible the institutionalised involvement of society in the control of risk, as well as of the mechanisms to realise it are the principal subjects of this work.
This work intends to analysis the philosophy of history and to discuss the consequences of this death to the Critical Theory. The concept of reason and the devices of democracy and human rights are discussed in a revision of the historical debate about the end of history operates the life in the interior of the modern society, especially about the intellectual condition at the information society.
Since the mid-1980s, there has been much federalism talk in Cameroon where federation (said to have been created in Foumban in 1961) had supposedly been 'overwhelmingly' rejected in 1972 by Cameroonians. 'Confusioncracy' is the one good term that could conveniently explain it. Written with the trilogy of criticism, provocation, and construction in mind, this book aims at reconstructing a new and vigorous society in Cameroon that ensures respect for fundamental human rights and certain basic shared values. Much as the book centres on the Anglophone Problem; it is principally about human rights and their excessive violations - the direct result of the absence of separation of powers and constitutionalism. It largely condemns Cameroon's government for incessantly singing democracy and rule of law at the same time as it is massively torturing and wantonly killing citizens that dare to question the confusion. While sharing the position that a state like Cameroon must be seen to ensure that its laws and other practices accord with its international commitments, the book nonetheless strives to apportion the blame for Cameroon's human rights catastrophe accordingly; showing how the English-speaking minority itself, generally speaking, contributes to a large extent in propping up the dictatorship that is oppressing not only that minority but Cameroonians at large. The book challenges Cameroon to assume a leadership role in uniting Africans through meaningful federalization rather than further splitting them into incapable mini-states on the challenging world stage.
The main goal of adequate organ preservation is to avoid further cellular metabolism during the phase of ischemia. However, modern preservation solutions do rarely achieve this target. In donor organs hypoxia and ischemia induce a broad spectrum of pathologic molecular mechanisms favoring primary graft dysfunction (PGD) after transplantation. Increased hypoxia-induced transcriptional activity leads to increased vascular permeability which in turn is the soil of a reperfusion edema and the enhancement of a pro-inflammatory response in the graft after reperfusion. We hypothesize that inhibition of the respiration chain in mitochondria and thus inhibition of the hypoxia induced mechanisms might reduce reperfusion edema and consecutively improve survival in vivo. In this study we demonstrate that the rotenoid Deguelin reduces the expression of hypoxia induced target genes, and especially VEGF-A, dose-dependently in hypoxic human lung derived cells. Furthermore, Deguelin significantly suppresses the mRNA expression of the HIF target genes VEGF-A, the pro-inflammatory CXCR4 and ICAM-1 in ischemic lungs vs. control lungs. After lung transplantation, the VEGF-A induced reperfusion-edema is significantly lower in Deguelin-treated animals than in controls. Deguelin-treated rats exhibit a significantly increased survival-rate after transplantation. Additionally, a downregulation of the pro-inflammatory molecules ICAM-1 and CXCR4 and an increase in the recruitment of immunomodulatory monocytes (CD163+ and CD68+) to the transplanted organ involving the IL4 pathway was observed. Therefore, we conclude that ischemic periods preceding reperfusion are mainly responsible for the increased vascular permeability via upregulation of VEGF. Together with this, the resulting endothelial dysfunction also enhances inflammation and consequently lung dysfunction. Deguelin significantly decreases a VEGF-A induced reperfusion edema, induces the recruitment of immunomodulatory monocytes and thus improves organ function and survival after lung transplantation by interfering with hypoxia induced signaling.
Background: Europe was certified to be polio-free in 2002 by the WHO. However, wild polioviruses remain endemic in India, Pakistan, Afghanistan, and Nigeria, occasionally causing polio outbreaks, as in Tajikistan in 2010. Therefore, effective surveillance measures and vaccination campaigns remain important. To determine the poliovirus immune status of a German study population, we retrospectively evaluated the seroprevalence of neutralizing antibodies (NA) to the poliovirus types 1, 2 and 3 (PV1, 2, 3) in serum samples collected from 1,632 patients admitted the University Hospital of Frankfurt am Main, Germany, in 2001, 2005 and 2010.
Methods: Testing was done by using a standardized microneutralization assay.
Results: Level of immunity to PV1 ranged between 84.2% (95%CI: 80.3-87.5), 90.4% (88.3-92.3) and 87.5% (85.4-88.8) in 2001, 2005 and 2010. For PV2, we found 90.8% (87.5-90.6), 91.3% (89.3-93.1) and 89.8% (88.7-90.9), in the same period. Seroprevalence to PV3 was 76.6% (72.2-80.6), 69.8% (66.6-72.8) and 72.9% (67.8-77.5) in 2001 and 2005 and 2010, respectively. In 2005 and 2010 significant lower levels of immunity to PV3 in comparison to PV1 and 2 were observed. Since 2001, immunity to PV3 is gradually, but not significantly decreasing.
Conclusion: Immunity to PV3 is insufficient in our cohort. Due to increasing globalization and worldwide tourism, the danger of polio-outbreaks is not averted - even not in developed countries, such as Germany. Therefore, vaccination remains necessary.
The present study describes five new free-living nematode species and provides three new species records of the family Comesomatidae (genera Cervonema Wieser, 1954, Dorylaimopsis Ditlevsen, 1918, Hopperia Vitiello, 1969, and Kenyanema Muthumbi et al., 1997) from the continental margin of New Zealand, Southwest Pacific. Dichotomous identification keys are provided for all known species of Dorylaimopsis and Hopperia. Cervonema shiae Chen & Vincx, 2000 is recorded for the first time outside the type locality (Beagle Channel, Chile). C. kaikouraensis sp. nov. is characterised by amphideal fovea with 5.5 turns situated at 1.7 head diameter from anterior end, jointed outer labial setae, equal in length to cephalic setae, sperm dimorphism, and 5-6 small pre-cloacal supplements. C. multispira sp. nov. is characterised by amphideal fovea with 8.0-8.5 turns situated at 2.6-4.0 head diameter from anterior end, cephalic setae 2-3 μm long, slightly shorter than outer labial setae, presence of six uninucleated cells in males (potentially pseudocoelomocytes or supplementary excretory cells), 5 small pre-cloacal supplements, and strongly cuticularised, arcuate spicules with capitulum. C. proberti sp. nov. is characterised by amphideal fovea with 5 turns and located at < 1 head diameter from anterior end, cephalic setae 1.6-2.0 times longer than outer labial setae, and 8 small pre-cloacal supplements. Dorylaimopsis nodderi sp. nov. is characterised by cuticle with lateral differentiation consisting of three longitudinal rows of larger dots in the pharyngeal and caudal regions, two rows of larger dots in middle region of body, and spicules with rounded ventral projection at one third of spicule length from distal end, giving appearance of a joint. Hopperia ancora sp. nov. is characterised by short conical cephalic setae, spicules with hook-like projection at distal end, gubernaculum with bent apophyses, and 11-13 pre-cloacal supplements. H. beaglense Chen & Vincx, 1998 is recorded from Kaikoura Canyon, the fi rst record of this species outside the type locality (Beagle Channel, Chile). Kenyanema monorchis Muthumbi et al., 1997 is also recorded for the first time outside the type locality (Indian Ocean).
Decorin, a member of the small leucine-rich proteoglycan gene family, exists and functions wholly within the tumor microenvironment to suppress tumorigenesis by directly targeting and antagonizing multiple receptor tyrosine kinases, such as the EGFR and Met. This leads to potent and sustained signal attenuation, growth arrest, and angiostasis. We thus sought to evaluate the tumoricidal benefits of systemic decorin on a triple-negative orthotopic breast carcinoma xenograft model. To this end, we employed a novel high-density mixed expression array capable of differentiating and simultaneously measuring gene signatures of both Mus musculus (stromal) and Homo sapiens (epithelial) tissue origins. We found that decorin protein core modulated the differential expression of 374 genes within the stromal compartment of the tumor xenograft. Further, our top gene ontology classes strongly suggests an unexpected and preferential role for decorin protein core to inhibit genes necessary for immunomodulatory responses while simultaneously inducing expression of those possessing cellular adhesion and tumor suppressive gene properties. Rigorous verification of the top scoring candidates led to the discovery of three genes heretofore unlinked to malignant breast cancer that were reproducibly found to be induced in several models of tumor stroma. Collectively, our data provide highly novel and unexpected stromal gene signatures as a direct function of systemic administration of decorin protein core and reveals a fundamental basis of action for decorin to modulate the tumor stroma as a biological mechanism for the ascribed anti-tumorigenic properties.
Mitochondrial dynamics and mitophagy play a key role in ensuring mitochondrial quality control. Impairment thereof was proposed to be causative to neurodegenerative diseases, diabetes, and cancer. Accumulation of mitochondrial dysfunction was further linked to aging. Here we applied a probabilistic modeling approach integrating our current knowledge on mitochondrial biology allowing us to simulate mitochondrial function and quality control during aging in silico. We demonstrate that cycles of fusion and fission and mitophagy indeed are essential for ensuring a high average quality of mitochondria, even under conditions in which random molecular damage is present. Prompted by earlier observations that mitochondrial fission itself can cause a partial drop in mitochondrial membrane potential, we tested the consequences of mitochondrial dynamics being harmful on its own. Next to directly impairing mitochondrial function, pre-existing molecular damage may be propagated and enhanced across the mitochondrial population by content mixing. In this situation, such an infection-like phenomenon impairs mitochondrial quality control progressively. However, when imposing an age-dependent deceleration of cycles of fusion and fission, we observe a delay in the loss of average quality of mitochondria. This provides a rational why fusion and fission rates are reduced during aging and why loss of a mitochondrial fission factor can extend life span in fungi. We propose the ‘mitochondrial infectious damage adaptation’ (MIDA) model according to which a deceleration of fusion–fission cycles reflects a systemic adaptation increasing life span.
Death of Hardship
(2012)
Death of Hardship kaleidoscopically unveils human intrigues, predicaments and woes. It brings into sharp focus the most dreaded products of cruel oppression, exploitation, and destruction - the worst forms of human degradation and sufferings. However, it also sheds beams of hope, celebrating optimism in the struggle and eventually opening the curtain to the stage of victory of the oppressed and impoverished under the shameless sky.
Temporal variation in the detectability of a species can bias estimates of relative abundance if not handled correctly. For example, when effort varies in space and/or time it becomes necessary to take variation in detectability into account when data are analyzed. We demonstrate the importance of incorporating seasonality into the analysis of data with unequal sample sizes due to lost traps at a particular density of a species. A case study of count data was simulated using a spring-active carabid beetle. Traps were ‘lost’ randomly during high beetle activity in high abundance sites and during low beetle activity in low abundance sites. Five different models were fitted to datasets with different levels of loss. If sample sizes were unequal and a seasonality variable was not included in models that assumed the number of individuals was log-normally distributed, the models severely under- or overestimated the true effect size. Results did not improve when seasonality and number of trapping days were included in these models as offset terms, but only performed well when the response variable was specified as following a negative binomial distribution. Finally, if seasonal variation of a species is unknown, which is often the case, seasonality can be added as a free factor, resulting in well-performing negative binomial models. Based on these results we recommend (a) add sampling effort (number of trapping days in our example) to the models as an offset term, (b) if precise information is available on seasonal variation in detectability of a study object, add seasonality to the models as an offset term; (c) if information on seasonal variation in detectability is inadequate, add seasonality as a free factor; and (d) specify the response variable of count data as following a negative binomial or over-dispersed Poisson distribution.
Saccharomyces cerevisiae CEN.PK 113-7D is widely used for metabolic engineering and systems biology research in industry and academia. We sequenced, assembled, annotated and analyzed its genome. Single-nucleotide variations (SNV), insertions/deletions (indels) and differences in genome organization compared to the reference strain S. cerevisiae S288C were analyzed. In addition to a few large deletions and duplications, nearly 3000 indels were identified in the CEN.PK113-7D genome relative to S288C. These differences were overrepresented in genes whose functions are related to transcriptional regulation and chromatin remodelling. Some of these variations were caused by unstable tandem repeats, suggesting an innate evolvability of the corresponding genes. Besides a previously characterized mutation in adenylate cyclase, the CEN.PK113-7D genome sequence revealed a significant enrichment of non-synonymous mutations in genes encoding for components of the cAMP signalling pathway. Some phenotypic characteristics of the CEN.PK113-7D strains were explained by the presence of additional specific metabolic genes relative to S288C. In particular, the presence of the BIO1 and BIO6 genes correlated with a biotin prototrophy of CEN.PK113-7D. Furthermore, the copy number, chromosomal location and sequences of the MAL loci were resolved. The assembled sequence reveals that CEN.PK113-7D has a mosaic genome that combines characteristics of laboratory strains and wild-industrial strains.
Allogeneic stem cell transplantation (allo-SCT) has become an important treatment modality for patients with high-risk acute myeloid leukemia (AML) and is also under investigation for soft tissue sarcomas. The therapeutic success is still limited by minimal residual disease (MRD) status ultimately leading to patients’ relapse. Adoptive donor lymphocyte infusions based on MRD status using IL-15-expanded cytokine-induced killer (CIK) cells may prevent relapse without causing graft-versus-host-disease (GvHD). To generate preclinical data we developed mouse models to study anti-leukemic- and anti-tumor-potential of CIK cells in vivo. Immunodeficient mice (NOD/SCID/IL-2Rγc−, NSG) were injected intravenously with human leukemic cell lines THP-1, SH-2 and with human rhabdomyosarcoma (RMS) cell lines RH41 and RH30 at minimal doses required for leukemia or tumor engraftment. Mice transplanted with THP-1 or RH41 cells were randomly assigned for analysis of CIK cell treatment. Organs of mice were analyzed by flow cytometry as well as quantitative polymerase chain reaction for engraftment of malignant cells and CIK cells. Potential of CIK cells to induce GvHD was determined by histological analysis. Tissues of the highest degree of THP-1 cell expansion included bone marrow followed by liver, lung, spleen, peripheral blood (PB), and brain. RH30 and RH41 engraftment mainly took place in liver and lung, but was also detectable in spleen and PB. In spite of delayed CIK cell expansion compared with malignant cells, CIK cells injected at equal amounts were sufficient for significant reduction of RH41 cells, whereas against fast-expanding THP-1 cells 250 times more CIK than THP-1 cells were needed to achieve comparable results. Our preclinical in vivo mouse models showed a reliable 100% engraftment of malignant cells which is essential for analysis of anti-cancer therapy. Furthermore our data demonstrated that IL-15-activated CIK cells have potent cytotoxic capacity against AML and RMS cells without causing GvHD.
Background: The branched chain alcohol isobutanol exhibits superior physicochemical properties as an alternative biofuel. The yeast Saccharomyces cerevisiae naturally produces low amounts of isobutanol as a by-product during fermentations, resulting from the catabolism of valine. As S. cerevisiae is widely used in industrial applications and can easily be modified by genetic engineering, this microorganism is a promising host for the fermentative production of higher amounts of isobutanol.
Results: Isobutanol production could be improved by re-locating the valine biosynthesis enzymes Ilv2, Ilv5 and Ilv3 from the mitochondrial matrix into the cytosol. To prevent the import of the three enzymes into yeast mitochondria, N-terminally shortened Ilv2, Ilv5 and Ilv3 versions were constructed lacking their mitochondrial targeting sequences. SDS-PAGE and immunofluorescence analyses confirmed expression and re-localization of the truncated enzymes. Growth tests or enzyme assays confirmed enzymatic activities. Isobutanol production was only increased in the absence of valine and the simultaneous blockage of the mitochondrial valine synthesis pathway. Isobutanol production could be even more enhanced after adapting the codon usage of the truncated valine biosynthesis genes to the codon usage of highly expressed glycolytic genes. Finally, a suitable ketoisovalerate decarboxylase, Aro10, and alcohol dehydrogenase, Adh2, were selected and overexpressed. The highest isobutanol titer was 0.63 g/L at a yield of nearly 15 mg per g glucose.
Conclusion: A cytosolic isobutanol production pathway was successfully established in yeast by re-localization and optimization of mitochondrial valine synthesis enzymes together with overexpression of Aro10 decarboxylase and Adh2 alcohol dehydrogenase. Driving forces were generated by blocking competition with the mitochondrial valine pathway and by omitting valine from the fermentation medium. Additional deletion of pyruvate decarboxylase genes and engineering of co-factor imbalances should lead to even higher isobutanol production.
We recorded the tent-web spider Cyrtophora citricola (Forsskål, 1775) (Araneidae: Cyrtophorinae) from Turkey for the first time at two sites. Body measurements and a brief description of the female are presented, as well as information on the sites (olive and orange orchards, shrubs) and the accompanying spider fauna.
The influence of an ac current of arbitrary amplitude and frequency on the mixed-state dc-voltage-ac-drive tiltingratchet response of a superconducting film with uniaxial cosine pinning potential at finite temperature is theoretically investigated. The results are obtained in the single-vortex approximation, within the frame of an exact solution of the Langevin equation for non-interacting vortices. Both experimentally achievable, the dc ratchet response and absorbed ac power are predicted to demonstrate a pronounced filter-like behavior at microwave frequencies. Based on our findings, we propose a cut-off filter and discuss its operating curves as functions of the driving parameters, i.e, ac amplitude, frequency, and dc bias. The predicted results can be examined, e.g, on superconducting films with a washboard pinning potential landscape.
'[C]ulture as text' initially proved to be a pivotal bridging metaphor between cultural anthropology and literary studies. Following an admittedly ambivalent career path, the concept of 'culture as text' has nevertheless continued to rise and has become an over-determined general principle, an emphatic key metaphor, even an overall "programmatic motto for the study of culture" […]. At first, this concept was still closely connected to ethnographic research and to the semiotic framework of interpretive cultural anthropology. However, since the end of the 1990s it has been utilised to encompass a much broader interdisciplinary horizon for the study of culture. 'Culture as text' advanced from being a conceptual metaphor for the condensation of cultural meanings to a rather free-floating formula frequently referred to in analyses within disciplines involved in the study of culture. Surprisingly, 'culture as text' has remained a consistent key phrase throughout the discourses concerned with the study of culture—even after the culture debate had long since turned away from the holistic understanding of culture implied by the formula.
The habitat as well as the unicellular thallus margins of Aneura maxima lead to the assumption that this species could be a hygromorphosis of A. pinguis. Therefore specimens of A. pinguis were cultivated in water. Even after four months the multicellular thallus margins were retained, which proved to be a stable character to separate A. pinguis from A. maxima. Therefore plants even with a small unistratose border, which are attributed to aquatic forms of A. pinguis, may belong to A. maxima. It is supposed that A. maxima was overlooked in Europe but regarded as aquatic forms of A. pinguis named as fo. rivularis. Such plants show unicellular thallus margins and are regarded as hygrophytic form of A. maxima. The presence viz. absence of an unicellular thallus margin seems to be a sufficient character to separate both species. The discussion about the width of the unistratose thallus margin is useless because the type of A. maxima has only 2-4 rows of unicellular cells and not 6-12 or more as attributed by European hepaticologists. This raises doubts whether the European material is identical with A. maxima rather with A. pellioides from Japan.
Cryptogams form a large part of dry grassland plant species richness. As a frequently used tool in grassland restoration, hay transfer is known to transfer cryptogam species. This might result in cryptogam stands differing from those achieved by natural succession. To assess hay transfer as a medium for cryptogam restoration, I analysed species composition of cryptogams in the hay of dry grasslands in Southern Germany, how fast they establish, and how fast they colonize adjacent plots. Cryptogam samples from hay showed species combinations similar to those of the mown sites and large shoot numbers to be present in the hay. Even low-growing and rare species were found in the hay. Hay receptor sites showed larger pleurocarpous moss and fruticose lichen patches than comparable sites without hay transfer, indicating earlier arrival of viable diaspores at the receptor sites. For acrocarpous mosses that colonize new sites by spores, no differences in turf size between succession and restoration plots were found. This shows that species transferred by hay have a distinct advantage over species that have to arrive at newly opened sites by natural means, i.e. many years later. The colonization from small restoration sites into adjacent areas without hay transfer proceeds with moderate speeds of about 1 to 2 m per year, probably with wind drift as the most important dispersal agent. Abundant cryptogam species including most pleurocarpous mosses and some Cladonia species rarely producing spores will be greatly enhanced by hay transfer. Nevertheless, the facilitation of pleurocarpous mosses may be detrimental to acrocarpous moss and epigaeic and saxicolous lichen species diversity, which should be considered in dry grassland restoration. I suggest a combination of different restoration measures in a mosaic pattern to create suitable conditions for a maximum of cryptogam species.
A decade since the availability of Mycobacterium tuberculosis (Mtb) genome sequence, no promising drug has seen the light of the day. This not only indicates the challenges in discovering new drugs but also suggests a gap in our current understanding of Mtb biology. We attempt to bridge this gap by carrying out extensive re-annotation and constructing a systems level protein interaction map of Mtb with an objective of finding novel drug target candidates. Towards this, we synergized crowd sourcing and social networking methods through an initiative ‘Connect to Decode’ (C2D) to generate the first and largest manually curated interactome of Mtb termed ‘interactome pathway’ (IPW), encompassing a total of 1434 proteins connected through 2575 functional relationships. Interactions leading to gene regulation, signal transduction, metabolism, structural complex formation have been catalogued. In the process, we have functionally annotated 87% of the Mtb genome in context of gene products. We further combine IPW with STRING based network to report central proteins, which may be assessed as potential drug targets for development of drugs with least possible side effects. The fact that five of the 17 predicted drug targets are already experimentally validated either genetically or biochemically lends credence to our unique approach.
Race has been a term avoided in the Swedish debates, while at the same time, protections with respect to unlawful discrimination on the basis of race or ethnic origins have not been vigilantly upheld by the courts. This paper looks at the treatment of race by the Swedish legislature, as well as the treatment by the courts, specifically the Labour Court, with respect to claims of unlawful discrimination in employment on the basis of ethnic origins, against the background of Critical Race Theory. The disparities between the intent of the legislature and the outcome of the cases brought to the Swedish courts can be in least in part explained through the lens of Critical Race Theory, particularly with respect to the liberal approach taken by the courts when applying the law.
Since the XIX century, a pleiad of philosophers and historians support the idea that Greek philosophy, usually reported to have started with the presocratics, lays its basis in a previous moment: the Greek myths – systematized by Homer and Hesiod – and the Greek arts, in particular the lyric and tragedy literature. According to this, it is important to retrieve philosophical elements even before the pre-Socratics to understand the genesis of specific concepts in Philosophy of Law. Besides, assuming that the Western’s core values are inherited from Ancient Greece, it is essential to recuperate the basis of our own justice idea, through the Greek myths and tragedy literature. As a case study, this paper aims on the comparison of two key-works, each one representing a phase of the Greek tragedy: The Orestea, by Aeschylus, and Orestes, by Euripides. Both contain the same story, telling how the Greeks understood the necessity of solving their conflicts not by blood revenge, but through a political way, and also the political drama. Although, in Aeschylus’s one, men still leashed by their fate, while the gods play a major role, in order to punish human pride (hybris). In a different way, on Euripides’s work men face their own loneliness, in a world fulfilled with gods, each one demanding divergent actions. That represents a necessary moment to the flourishing freedom and human subjectivity, and, once the exterior divinity is unable to resolve human problems, men will need to discover their interior divinity: that is how the Philosophy emerges.
The demarcation of authority between parents and the State regarding education of children has become an increasingly complex issue over the past three decades. During the same period the number of parents around the world choosing educational alternatives such as homeschooling has grown exponentially, causing significant legislative and jurisprudential shifts in the United States as well as other Western nations. If the State is responsible for education or has a significant interest therein, then it must have broad authority by which to prescribe the method, mechanism, and acceptable outcomes of education; it must also be able to review and enforce these desired outcomes. If parents, on the other hand, are responsible, then it is the State’s duty to defer to parents absent a compelling reason to interfere. A survey of the philosophical foundations from ancient to modern times demonstrates the tension between the State and parents in the realm of education; however, modern human rights norms contained in post-1945 international human rights documents provide explicit grounds on which the State must defer to parental choice in education.
The most popularised concept in the economics of innovation literature has been the national system of innovation (NSI). It was in the late 1980s that the concept that Frederik List coined as the National Political Economy of Production took off again with different thinkers writing about the peculiarities and distinctions of the Japanese, American, British, German, East Asian Tigers and other varieties of system construction. Freeman defines National System of Innovation as the network of institutions in the public and private sectors whose activities and interactions initiate, import, modify and diff use new technologies. Richard Nelson defines it as a set of institutions whose interactions determine the innovative performance of national firms. Lundvall defines the system of innovation as the elements and relationships which interact in the production, diffusion and use of new and economically useful knowledge and are either located within or rooted inside the borders of a nation state. The normative assumption is that those nations that succeeded in building economic strength relied on the science, engineering, technology and innovation capability that made them to achieve an innovation advantage to put them ahead in the world, acquiring national or regional economic leadership as the case may be depending on what level of analyses is selected to look at particular failure, success or progress they made.. In this volume we have a glimpse of how in different African economies from Ghana, Uganda, Kenya, South Africa and Nigeria specific cases have been taken to explore how systems of innovation is evolving.
In dieser Arbeit werden Schmelz- und Anreicherungsprozesse des Erdmantels, sowie Kristallisationsereignisse der Erdkruste zweier ausgewählter Gebiete in Namibia und Spanien mithilfe geochemischer Methoden rekonstruiert und in einen zeitlichen Zusammenhang gebracht. Ein Vergleich der gewonnenen Ergebnisse beider Kompartimente soll dabei weitere Informationen liefern inwieweit Prozesse des Erdmantels und der Erdkruste miteinander verknüpft waren. Insbesondere soll ein weitere Beitrag zur aktuellen Diskussion geliefert werden, bei der sich das sogenannte „pulsed growth“ und „steady accumulation“ Modell gegenüberstehen (siehe Zusammenstellung Pearson et al., 2007). Zudem tragen die neu gewonnenen Daten dazu bei, die regionalen geologischen Gegebenheiten im besonderen Hinblick auf die geotektonische Geschichte besser zu verstehen.
Das Gibeon Kimberlit Feld befindet sich in der tektonischen Einheit des Rehoboth Terranes in Namibia und ist gekennzeichnet von Vulkanismus vor etwa 72.5 Ma (Davies et al., 2001), der Granat Peridotite und krustale Xenolithe mit an die Oberfläche beförderte. Eine klare Einordnung des Rehoboth Terranes in die Gesamtheit des Süd Afrikanischen Plattenverbunds ist noch nicht vollständig geklärt.
Die Südöstliche vulkanische Provinz in Spanien (SEVP) mit besonderem Hinblick auf die Region um Casas de Tallante stellt das zweite Probengebiet für diese Arbeit dar. Vor etwa 2.6 Ma (Bellon et al., 1983) kam es zur Extrusion von alkali-basaltischen Schmelzen, die zahlreiche Spinell / Plagioklas Peridotite mit sich brachten. Tufflagen, sowie die Matrix der Basalte ermöglichen einen Einblick in die untere Kruste der Region.
Untersuchungen der Erdmantelproben aus Namibia auf ihre Haupt- und Spurenelementchemie, sowie Lu-Hf und Sm-Nd Isotopie zeigten, dass zwei verschiedene Manteltypen vorliegen („N“ und „σ“ Typ), die zu einem Zeitpunkt um etwa 850 Ma („N“) und 1.9 Ga („σ“) angereichert wurden. Eine letzte Anreicherung beider Typen fand vermutlich während der Pan–Afrikanischen Orogenese um etwa 450 Ma statt. Die Reinterpretation eines zuvor publizierten Datensatzes (Pearson et al., 2004), suggeriert, dass es zu einer ersten Verarmung der σ Peridotite um etwa 2.9 Ga kam.
Untersuchungen der U-Pb und Hf Isotopie an Zirkonen aus der unteren Kruste des Probengebiets in Namibia ergaben, dass es zur Bildung von juvenilem Krustenmaterial vermutlich bereits im Archaikum kam (wie bereits vorgeschlagen durch z.B. Hoal et al., 1995; Franz et al., 1996), sowie in den Zeiträumen von 2.3 bis 2.7 und 1.5 bis 1.6 Ga, mit jeweils anschließendem krustalem Recycling und Krustenmischung. Eine Übereinstimmung von Mantel- und Krustenevents konnte für die Zeiträume von etwa 1.8, 0.8 - 0.9 Ga und 0.4 – 0.5 Ga gefunden werden. Eine mögliche erste Verarmung des σ Mantels wird bestätigt durch Zirkonalter im Bereich von 2.7 bis 2.9 Ga.
Die Analyse ausgewählter Spinell / Plagioklas Peridotite aus der SEVP, ergaben, dass ein heterogener Mantel mit mindestens 3 verschiedenen Typen vorliegt. Eine Korrelation der Lu-Hf Isotopie von 3 Proben dieses Probensatzes, sowie den Hf Isotopien einer weiteren Probe von Bianchini et al. (2011) suggerieren, dass es eventuell zu einem Verarmungsereignis zu einem Zeitpunkt von etwa 550 Ma kam. Sr Isotopien von Klinopyroxenen und Plagioklasen im Vergleich ergaben, dass die Sr Isotopie der Plagioklase, im Gegensatz zu den Klinopyroxenen, von denen der Alkali Basalte überprägt wurden.
Zirkonanalysen aus Lokalitäten innerhalb der SEVP (U-Pb, Hf) ergaben ein weitreichendes Altersspektrum, beginnend bei etwa 2-3 Ma bis hin ins Archaikum (2.7 bis 2.9 Ga) mit Provenance Ursprung aus Gondwana und dem Arabisch-Nubischen Schild. Die Kombination der U-Pb Altersinformationen mit den entsprechenden Hf Isotopien, zeigten, dass es vermutlich bereits im Archaikum zu juveniler Krustenbildung kam. Zirkone > 100 µm datieren den Zeitpunkt der Eruption der Alkali Basalte mit Altern um etwa 2.6 Ma und Hf Isotopien, die einem leicht verarmten Mantel entsprechen. Ein mögliches Verarmungsereignis im Erdmantel zu einem Zeitpunkt von etwa 550 Ma, ist im Einklang mit Krustenrecycling zu selbigem Zeitpunkt.
Die neugewonnenen Daten dieser Arbeit unterstützten das „pulsed growth“ Modell.
Literatur
Bellon, H., Bordet, P. and Montenat, C., 1983. Chronology of the Neogene Magmatism from Betic Ranges (Southern Spain). Bulletin De La Societe Geologique De France, 25(2): 205-217.
Bianchini, G., Beccaluva, L., Nowell, G.M., Pearson, D.G. and Siena, F., 2011. Mantle xenoliths from Tallante (Betic Cordillera): Insights into the multi-stage evolution of the south Iberian lithosphere. Lithos, 124(3-4): 308-318.
Davies, G.R., Spriggs, A.J. and Nixon, P.H., 2001. A non-cognate origin for the Gibeon kimberlite megacryst suite, Namibia: Implications for the origin of Namibian kimberlites. Journal of Petrology, 42(1): 159-172.
Franz, L., Brey, G.P. and Okrusch, M., 1996b. Steady state geotherm, thermal disturbances, and tectonic development of the lower lithosphere underneath the Gibeon Kimberlite Province, Namibia. Contributions to Mineralogy and Petrology, 126(1-2): 181-198.
Hoal, B.G., Hoal, K.E.O., Boyd, F.R. and Pearson, D.G., 1995. Age constraints on crustal and mantle lithosphere beneath the Gibeon kimberlite field, Namibia. South African Journal of Geology, 98(2): 112-118.
Pearson, D.G., Irvine, G.J., Ionov, D.A., Boyd, F.R. and Dreibus, G.E., 2004. Re-Os isotope systematics and platinum group element fractionation during mantle melt extraction: a study of massif and xenolith peridotite suites. Chemical Geology, 208(1-4): 29-59.
Pearson, D.G., Parman, S.W. and Nowell, G.M., 2007. A link between large mantle melting events and continent growth seen in osmium isotopes. Nature, 449(7159): 202-205.
The lipidome of the marine hyperthermophilic archaeon Pyrococcus furiosus was studied by means of combined thin-layer chromatography and MALDI-TOF/MS analyses of the total lipid extract. 80–90% of the major polar lipids were represented by archaeol lipids (diethers) and the remaining part by caldarchaeol lipids (tetraethers). The direct analysis of lipids on chromatography plate showed the presence of the diphytanylglycerol analogues of phosphatidylinositol and phosphatidylglycerol, the N-acetylglucosamine-diphytanylglycerol phosphate plus some caldarchaeol lipids different from those previously described. In addition, evidence for the presence of the dimeric ether lipid cardiolipin is reported, suggesting that cardiolipins are ubiquitous in archaea.
The subject of this thesis aimed at a better understanding of the spectacular X-ray burst. The most likely astrophysical site is a very dense neutron star, which accretes H/He-rich matter from a close companion. While falling towards the neutron star, the matter is heated up and a thermonuclear runaway is ignited. The exact description of this process is dominated by the properties of a few proton-rich radioactive isotopes, which have a low interaction probability, hence a high abundance.
The topic of this thesis was therefore an investigation of the short-lived, proton-rich isotopes 31Cl and 32Ar. The Coulomb dissociation method is the modern technique of choice. Excitations with energies up to 20 MeV can be induced by the Lorentz contracted Coulomb field of a lead target. At the GSI Helmholtzzentrum für Schwerionenforschung GmbH in Darmstadt, Germany, a Ar beam was accelerated to an energy of 825 AMeV and fragmented in a beryllium target. The fragment separator was used to select the desired isotopes with a remaining energy of 650 AMeV. They were subsequently directed onto a 208 Pb target in the ALAND/LAND setup. The measurement was performed in inverse kinematics. All reaction products were detected and inclusive and exclusive measurements of the respective Coulomb dissociation cross sections were possible.
During the analysis of the experiment, it was possible to extract the energy-differential excitation spectrum of 31Cl, and to constrain astrophysically important parameters for the time-reversed 30S(p,γ)31Cl reaction. A single resonance at 0.443(37) MeV dominates the stellar reaction rate, which was also deduced and compared to previous calculations.
The integrated Coulomb dissociation cross section of this resonance was determined to 15(6) mb. The astrophysically important one- and two-proton emission channels were analyzed for 32Ar and energy-differential excitation spectra could be derived. The integrated Coulomb dissociation cross section for two proton emission were determined with two different techniques. The inclusive measurement yields a cross section of 214(29stat)(20sys) mb, whereas the exclusive reconstruction results in a cross section of 226(14stat)(23sys) mb. Both results are in very good agreement. The Coulomb dissociation cross section for the one-proton emission channel is extracted solely from the exclusive measurement and is 54(8stat)(6sys) mb.
Furthermore, the development of the Low Energy Neutron detector Array (LENA) for the upcoming R3B setup is described. The detector will be utilized in charge-exchange reactions to detect the low-energy recoil neutrons from (p,n)-type reactions. These reaction studies are of particular importance in the astrophysical context and can be used to constrain half lifes under stellar conditions. In the frame of this work, prototypes of the detector were built and successfully commissioned in several international laboratories.
The analysis was supported by detailed simulations of the detection characteristics.
In the original manuscript, Figs. 7–16 included fonts which were not correctly embedded in the file. As such, unless certain propriety software (ArcGIS) is installed on the viewing platform, the figures will appear corrupted. In this Corrigendum, Figs. 7–16 and their captions are reproduced with the fonts correctly embedded. Please find the correct figures below.
Important missing specimen data are provided for the original description of Ozophora woodruffi Slater (2005: 245) (Hemiptera: Lygaeidae), along with additional comparative relationships. Because of the missing type information, according to ICZN rules (1999), the species became a nomen nudum. This paper now serves to validate the name, and authorship becomes Slater (2012).
A concurrent implementation of software transactional memory in Concurrent Haskell using a call-by-need functional language with processes and futures is given. The description of the small-step operational semantics is precise and explicit, and employs an early abort of conflicting transactions. A proof of correctness of the implementation is given for a contextual semantics with may- and should-convergence. This implies that our implementation is a correct evaluator for an abstract specification equipped with a big-step semantics.
ABSTRACT: In the original paper (Seidler et al. 2008), there is a mistake in the results of the occupational group analysis. This mistake occurred when the core data set was merged with the occupational group data. According to the modified occupational group analysis (see modified Table 1), OR for chemical processers and manufacturers of plastics products are no longer significantly elevated. Having worked more than 10 years as metal worker is associated with knee osteoarthritis (OR=2.2; 95% CI 1.1-4.4). The knee osteoarthritis risk of plasterers, insulators, glaziers, terrazzo workers, construction carpenters, roofers, and upholsters approaches statistical significance in the long-duration category (OR=3.7; 95% CI 0.9-15.2). For woodworkers, the knee osteoarthritis risk is no longer significantly elevated. Having worked more than 10 years as painter or varnisher is associated with knee osteoarthritis (OR=9.6; 95% CI 1.2-77.9). Finally, we find a significantly elevated OR of 3.2 (95% CI 1.1-9.1) among subjects having worked as physically exposed service workers (storemen, nurses, refuse collectors) for more than 10 years. When subjects with non-service work as main occupation ("blue-collar workers") are compared with "white-collar workers", the odds ratio for knee osteoarthritis is still significantly elevated (OR=2.0; 95% CI 1.3-2.9).
On 13 July 2010, in a woodland near the village of Verin Khotanan, Armenia, five males of Cordulegaster vanbrinkae were captured. These specimens are documented, compared with the holotype from Iran and discussed in detail. The current protection situation of this species in Armenia is briefly commented. In addition, the locus typicus information of the holotype from Iran is corrected and detailed.
In the juvenile brain, the synaptic architecture of the visual cortex remains in a state of flux for months after the natural onset of vision and the initial emergence of feature selectivity in visual cortical neurons. It is an attractive hypothesis that visual cortical architecture is shaped during this extended period of juvenile plasticity by the coordinated optimization of multiple visual cortical maps such as orientation preference (OP), ocular dominance (OD), spatial frequency, or direction preference. In part (I) of this study we introduced a class of analytically tractable coordinated optimization models and solved representative examples, in which a spatially complex organization of the OP map is induced by interactions between the maps. We found that these solutions near symmetry breaking threshold predict a highly ordered map layout. Here we examine the time course of the convergence towards attractor states and optima of these models. In particular, we determine the timescales on which map optimization takes place and how these timescales can be compared to those of visual cortical development and plasticity. We also assess whether our models exhibit biologically more realistic, spatially irregular solutions at a finite distance from threshold, when the spatial periodicities of the two maps are detuned and when considering more than 2 feature dimensions. We show that, although maps typically undergo substantial rearrangement, no other solutions than pinwheel crystals and stripes dominate in the emerging layouts. Pinwheel crystallization takes place on a rather short timescale and can also occur for detuned wavelengths of different maps. Our numerical results thus support the view that neither minimal energy states nor intermediate transient states of our coordinated optimization models successfully explain the architecture of the visual cortex. We discuss several alternative scenarios that may improve the agreement between model solutions and biological observations.
In the primary visual cortex of primates and carnivores, functional architecture can be characterized by maps of various stimulus features such as orientation preference (OP), ocular dominance (OD), and spatial frequency. It is a long-standing question in theoretical neuroscience whether the observed maps should be interpreted as optima of a specific energy functional that summarizes the design principles of cortical functional architecture. A rigorous evaluation of this optimization hypothesis is particularly demanded by recent evidence that the functional architecture of orientation columns precisely follows species invariant quantitative laws. Because it would be desirable to infer the form of such an optimization principle from the biological data, the optimization approach to explain cortical functional architecture raises the following questions: i) What are the genuine ground states of candidate energy functionals and how can they be calculated with precision and rigor? ii) How do differences in candidate optimization principles impact on the predicted map structure and conversely what can be learned about a hypothetical underlying optimization principle from observations on map structure? iii) Is there a way to analyze the coordinated organization of cortical maps predicted by optimization principles in general? To answer these questions we developed a general dynamical systems approach to the combined optimization of visual cortical maps of OP and another scalar feature such as OD or spatial frequency preference. From basic symmetry assumptions we obtain a comprehensive phenomenological classification of possible inter-map coupling energies and examine representative examples. We show that each individual coupling energy leads to a different class of OP solutions with different correlations among the maps such that inferences about the optimization principle from map layout appear viable. We systematically assess whether quantitative laws resembling experimental observations can result from the coordinated optimization of orientation columns with other feature maps.
Despite being internal organs, digestive structures are frequently preserved in Cambrian Lagerstätten. However, the reasons for their fossilisation and their biological implications remain to be thoroughly explored. This is particularly true with arthropods--typically the most diverse fossilised organisms in Cambrian ecosystems--where digestive structures represent an as-yet underexploited alternative to appendage morphology for inferences on their biology. Here we describe the phosphatised digestive structures of three trilobite species from the Cambrian Weeks Formation Lagerstätte (Utah). Their exquisite, three-dimensional preservation reveals unique details on trilobite internal anatomy, such as the position of the mouth and the absence of a differentiated crop. In addition, the presence of paired pygidial organs of an unknown function is reported for the first time. This exceptional material enables exploration of the relationships between gut phosphatisation and the biology of organisms. Indeed, soft-tissue preservation is unusual in these fossils as it is restricted to the digestive structures, which indicates that the gut played a central role in its own phosphatisation. We hypothesize that the gut provided a microenvironment where special conditions could develop and harboured a source of phosphorus. The fact that gut phosphatization has almost exclusively been observed in arthropods could be explained by their uncommon ability to store ions (including phosphorous) in their digestive tissues. However, in some specimens from the Weeks Formation, the phosphatisation extends to the entire digestive system, suggesting that trilobites might have had some biological particularities not observed in modern arthropods. We speculate that one of them might have been an increased capacity for ion storage in the gut tissues, related to the moulting of their heavily-mineralised carapace.
The importance of RNA in molecular and cell biology has long been underestimated. Besides transmitting genetic information, studies of recent years have revealed crucial tasks of RNA especially in gene regulation. Riboswitches are natural RNA-based genetic switches and known only for ten years. They directly sense small-molecule metabolites and regulate in response the expression of the corresponding metabolic genes. Within recent years, artificial riboswitches have been developed that operate according to user-defined demands. Hence, they represent powerful tools for synthetic biology.
This study focused on the development of engineered catalytic riboswitches for conditional gene expression in eukaryotes. A self-cleaving hammerhead ribozyme was linked to a tetracycline binding aptamer in order to regulate ribozyme cleavage allosterically with tetracycline. By integrating such a hybrid molecule into a gene of interest, mRNA cleavage and thereby gene expression is controllable in a ligand dependent manner. The linking domain between ribozyme and aptamer was randomised. Tetracycline inducible ribozymes were isolated after eleven cycles of in vitro selection (SELEX). 80% of the analysed ribozymes show cleavage that strongly depends on tetracycline. In the presence of 1 μM tetracycline, their cleavage rates are comparable to that of the parental hammerhead ribozyme. In the absence of tetracycline, cleavage rates are inhibited up to 333-fold. The allosteric ribozymes bind tetracycline with similar affinity and specificity as the parental aptamer. Ribozyme cleavage is fully induced within minutes after addition of tetracycline. Interestingly, the isolated linker domains exhibit structural consensus motives rather than consensus sequences.
When transferred to yeast, three switches reduced reporter gene expression by 30 - 60% in the presence of tetracycline; none of them controlled gene expression in mammalian cells. In vitro selected molecules do not necessarily retain their characteristics when applied in a cellular context. Therefore, high throughput screening and selection systems have been developed in mammalian cells. The screening system is based on two fluorescent reporter proteins (GFP and mCherry). 1152 individual constructs of the selected ribozyme pool were tested, but none of them reduced reporter gene expression significantly in the presence of tetracycline. The selection system employs a fusion peptide encoding two selection markers (Hygromycin B phosphotransferase and HSV thymidine kinase) facilitating both negative and positive selection. 6.5 x 104 individual constructs of the selected ribozyme pool are currently under investigation.
The species of the "modestus" group of the genus Psalidognathus Gray (Cerambycidae: Prioninae) (currently with four species and three subspecies), which are recognized mainly by the antennomeres without apical spines, are studied. Psalidognathus thomsoni Lameere, 1885 is revalidated as a species distinct from P. modestus Fries, 1833. Psalidognathus erythrocerus reichei Quentin and Villiers, 1983 and P. erythrocerus pubescens Quentin and Villiers, 1983 are considered as different species from P. erythrocerus Reiche, 1840. Psalidognathus colombianus Demelt, 1989 and Psalidognathus modestus chocoensis Salazar, 2005 are synonymized with P. modestus, syn. nov. Psalidognathus rufescens, although belonging to “friendii” group, is redescribed and some remarks are added. Species redescribed: P. erythrocerus; P. modestus; P. reichei; P. rufescens; P. onorei Quentin and Villiers, 1983; and P. thomsoni. Psalidognathus cerberus sp. nov. is described from Colombia and Ecuador. A provisional key is provided to males of species of "modestus" group.
Borrelia burgdorferi evades complement-mediated killing by interacting with complement regulators through distinct complement regulator-acquiring surface proteins (CRASPs). Here, we extend our analyses to the contribution of CRASP-4 in mediating complement resistance of B. burgdorferi and its interaction with human complement regulators. CRASP-4 (also known as ErpC) was immobilized onto magnetic beads and used to capture proteins from human serum. Following Western blotting, factor H (CFH), CFH-related protein 1 (CFHR1), CFHR2, and CFHR5 were identified as ligands of CRASP-4. To analyze the impact of native CRASP-4 on mediating survival of serum-sensitive cells in human serum, a B. garinii strain was generated that ectopically expresses CRASP-4. CRASP-4-producing bacteria bound CFHR1, CFHR2, and CFHR5 but not CFH. In addition, transformed spirochetes deposited significant amounts of lethal complement components on their surface and were susceptible to human serum, thus indicating that CRASP-4 plays a subordinate role in complement resistance of B. burgdorferi.
Contribution of sulfuric acid and oxidized organic compounds to particle formation and growth
(2012)
Lack of knowledge about the mechanisms underlying new particle formation and their subsequent growth is one of the main causes for the large uncertainty in estimating the radiative forcing of atmospheric aerosols in global models. We performed chamber experiments designed to study the contributions of sulfuric acid and organic vapors to formation and to the early growth of nucleated particles, respectively. Distinct experiments in the presence of two different organic precursors (1,3,5-trimethylbenzene and α-pinene) showed the ability of these compounds to reproduce the formation rates observed in the low troposphere. These results were obtained measuring the sulfuric acid concentrations with two Chemical Ionization Mass Spectrometers confirming the results of a previous study which modeled the sulfuric acid concentrations in presence of 1,3,5-trimethylbenzene.
New analysis methods were applied to the data collected with a Condensation Particle Counter battery and a Scanning Mobility Particle Sizer, allowing the assessment of the size resolved growth rates of freshly nucleated particles. The effect of organic vapors on particle growth was investigated by means of the growth rate enhancement factor (Γ), defined as the ratio between the measured growth rate in the presence of α-pinene and the kinetically limited growth rate of the sulfuric acid and water system. The observed Γ values indicate that the growth is dominated by organic compounds already at particle diameters of 2 nm. Both the absolute growth rates and Γ showed a strong dependence on particle size supporting the nano-Köhler theory. Moreover, the separation of the contributions from sulfuric acid and organic compounds to particles growth reveals that the organic contribution seems to be enhanced by the sulfuric acid concentration. The size resolved growth analysis finally indicates that both condensation of oxidized organic compounds and reactive uptake contribute to particle growth.
Contribution of sulfuric acid and oxidized organic compounds to particle formation and growth
(2012)
Lack of knowledge about the mechanisms underlying new particle formation and their subsequent growth is one of the main causes for the large uncertainty in estimating the radiative forcing of atmospheric aerosols in global models. We performed chamber experiments designed to study the contributions of sulfuric acid and organic vapors to the formation and early growth of nucleated particles. Distinct experiments in the presence of two different organic precursors (1,3,5-trimethylbenzene and α-pinene) showed the ability of these compounds to reproduce the formation rates observed in the low troposphere. These results were obtained measuring the sulfuric acid concentrations with two chemical ionization mass spectrometers confirming the results of a previous study which modeled the sulfuric acid concentrations in presence of 1,3,5-trimethylbenzene.
New analysis methods were applied to the data collected with a condensation particle counter battery and a scanning mobility particle sizer, allowing the assessment of the size resolved growth rates of freshly nucleated particles. The effect of organic vapors on particle growth was investigated by means of the growth rate enhancement factor (Γ), defined as the ratio between the measured growth rate in the presence of α-pinene and the kinetically limited growth rate of the sulfuric acid and water system. The observed Γ values indicate that the growth is already dominated by organic compounds at particle diameters of 2 nm. Both the absolute growth rates and Γ showed a strong dependence on particle size, supporting the nano-Köhler theory. Moreover, the separation of the contributions from sulfuric acid and organic compounds to particle growth reveals that the organic contribution seems to be enhanced by the sulfuric acid concentration. Finally, the size resolved growth analysis indicates that both condensation of oxidized organic compounds and reactive uptake contribute to particle growth.
Contribution of awareness information in virtual communities – the case of a financial institution
(2012)
IN DISTRIBUTED WORK ENVIRONMENTS, IT IS A CHALLENGING ISSUE FOR ORGANIZATIONS TO SUPPORT THEIR EMPLOYEES IN STAYING AWARE OF ALL IMPORTANT DEVELOPMENTS IN THEIR WORK ENVIRONMENT. ACCORDINGLY, IN THIS STUDY WE DEVELOP AND EMPICALLY TEST A CONCEPTUAL MODEL TO ENHANCE OUR UNDERSTANDING OF THE INDIVIDUALS’ CONTRIBUTION BEHAVIOR OF AWARENESS INFORMATION. WE PROVIDE GUIDANCE FOR THE DESIGN AND EVALUATION OF INFORMATION SYSTEMS TO SUPPORT THE CREATION OF SITUATION AWARENESS.
Background: The diagnostic and pathophysiological relevance of antibodies to aquaporin-4 (AQP4-Ab) in patients with neuromyelitis optica spectrum disorders (NMOSD) has been intensively studied. However, little is known so far about the clinical impact of AQP4-Ab seropositivity.
Objective: To analyse systematically the clinical and paraclinical features associated with NMO spectrum disorders in Caucasians in a stratified fashion according to the patients' AQP4-Ab serostatus.
Methods: Retrospective study of 175 Caucasian patients (AQP4-Ab positive in 78.3%).
Results: Seropositive patients were found to be predominantly female (p < 0.0003), to more often have signs of co-existing autoimmunity (p < 0.00001), and to experience more severe clinical attacks. A visual acuity of ≤ 0.1 during acute optic neuritis (ON) attacks was more frequent among seropositives (p < 0.002). Similarly, motor symptoms were more common in seropositive patients, the median Medical Research Council scale (MRC) grade worse, and MRC grades ≤ 2 more frequent, in particular if patients met the 2006 revised criteria (p < 0.005, p < 0.006 and p < 0.01, respectively), the total spinal cord lesion load was higher (p < 0.006), and lesions ≥ 6 vertebral segments as well as entire spinal cord involvement more frequent (p < 0.003 and p < 0.043). By contrast, bilateral ON at onset was more common in seronegatives (p < 0.007), as was simultaneous ON and myelitis (p < 0.001); accordingly, the time to diagnosis of NMO was shorter in the seronegative group (p < 0.029). The course of disease was more often monophasic in seronegatives (p < 0.008). Seropositives and seronegatives did not differ significantly with regard to age at onset, time to relapse, annualized relapse rates, outcome from relapse (complete, partial, no recovery), annualized EDSS increase, mortality rate, supratentorial brain lesions, brainstem lesions, history of carcinoma, frequency of preceding infections, oligoclonal bands, or CSF pleocytosis. Both the time to relapse and the time to diagnosis was longer if the disease started with ON (p < 0.002 and p < 0.013). Motor symptoms or tetraparesis at first myelitis and > 1 myelitis attacks in the first year were identified as possible predictors of a worse outcome.
Conclusion: This study provides an overview of the clinical and paraclinical features of NMOSD in Caucasians and demonstrates a number of distinct disease characteristics in seropositive and seronegative patients
Even in V1, where neurons have well characterized classical receptive fields (CRFs), it has been difficult to deduce which features of natural scenes stimuli they actually respond to. Forward models based upon CRF stimuli have had limited success in predicting the response of V1 neurons to natural scenes. As natural scenes exhibit complex spatial and temporal correlations, this could be due to surround effects that modulate the sensitivity of the CRF. Here, instead of attempting a forward model, we quantify the importance of the natural scenes surround for awake macaque monkeys by modeling it non-parametrically. We also quantify the influence of two forms of trial to trial variability. The first is related to the neuron’s own spike history. The second is related to ongoing mean field population activity reflected by the local field potential (LFP). We find that the surround produces strong temporal modulations in the firing rate that can be both suppressive and facilitative. Further, the LFP is found to induce a precise timing in spikes, which tend to be temporally localized on sharp LFP transients in the gamma frequency range. Using the pseudo R2 as a measure of model fit, we find that during natural scene viewing the CRF dominates, accounting for 60% of the fit, but that taken collectively the surround, spike history and LFP are almost as important, accounting for 40%. However, overall only a small proportion of V1 spiking statistics could be explained (R2~5%), even when the full stimulus, spike history and LFP were taken into account. This suggests that under natural scene conditions, the dominant influence on V1 neurons is not the stimulus, nor the mean field dynamics of the LFP, but the complex, incoherent dynamics of the network in which neurons are embedded.
All over Africa, an explosion in cultural productions of various genres is in evidence. Whether in relation to music, song and dance, drama, poetry, film, documentaries, photography, cartoons, fine arts, novels and short stories, essays, and (auto)biography; the continent is experiencing a robust outpouring of creative power that is as remarkable for its originality as its all-round diversity. Beginning from the late 1970s and early 1980s, the African continent has experienced the longest and deepest economic crises than at any other time since the period after the Second World War. Interestingly however, while practically every indicator of economic development was declining in nominal and/ or real terms for most aspects of the continent, cultural productions were on the increase. Out of adversity, the creative genius of the African produced cultural forms that at once spoke to crises and sought to transcend them. The current climate of cultural pluralism that has been produced in no small part by globalization has not been accompanied by an adequate pluralism of ideas on what culture is, and/or should be; nor informed by an equal claim to the production of the cultural - packaged or not. Globalization has seen to movement and mixture, contact and linkage, interaction and exchange where cultural flows of capital, people, commodities, images and ideologies have meant that the globe has become a space, with new asymmetries, for an increasing intertwinement of the lives of people and, consequently, of a greater blurring of normative definitions as well as a place for re-definition, imagined and real. As this book - Contemporary African Cultural Productions - has done, researching into African culture and cultural productions that derive from it allows us, among other things, to enquire into definitions, explore historical dimensions, and interrogate the political dimensions to presentation and representation. The book therefore offers us an intervention that goes beyond the normative literary and cultural studies' main foci of race, difference and identity; notions which, while important in themselves might, without the necessary historicizing and interrogating, result in a discourse that rather re-inscribes the very patterns that necessitate writing against. This book is an invaluable compendium to scholars, researchers, teachers, students and others who specialize on different aspects of African culture and cultural productions, as well as cultural centers and general readers.
In its decision of December 13, 2011, the Constitutional Court of the state of North Rhine-Westphalia ruled that a State Court of Auditors is granted by the constitution a broad scope of powers not only to control the immediate state administration but also entities outside the direct state administration, as far as they exercise financial responsibility for the state. This ruling may have serious implications for the capital guarantees extended by EU Member States to the newly established institutions on the European level, as for instance the European Stability Mechanism (ESM).
Based on Walter Benjamin’s reflections on history and social struggles, this paper drafts an analysis of the relations of the subject with some problems of constitutional theory, in a first effort to bring the field nearer to social philosophy. After tracing a short narrative on modern constitutionalism and its new relationship with the historical time, we argument that Constitution shall be seen as a cultural document of memory of the social struggles of the past and at the same an object of the struggles of the present. Some inconclusive reflections on the possibility of human emancipation through law are presented as conclusion.
We investigate the ratios βη≡η/τπ and βζ≡ζ/τΠ, i.e., the ratios of shear, η, and bulk, ζ, viscosities to the relaxation times τπ, τΠ of the shear stress tensor and bulk viscous pressure, respectively, in the framework of causal relativistic dissipative fluid dynamics. These viscous transport coefficients are computed both in a field-theoretical and a kinetic approach based on the Boltzmann equation. Our results differ from those of the traditional Boltzmann calculation by Israel and Stewart. The new expressions for the viscous transport coefficients agree with the results obtained in the field-theoretical approach when the contributions from pair annihilation and creation (PAC) are neglected. The latter induce non-negligible corrections to the viscous transport coefficients.
This paper seeks to analyse the debate on equality between women and men found in the claims against the subjects related to Education for Citizenship. These claims were resolved in the Spanish Supreme Court and High Courts of the Autonomous Communities. In this debate, there is a strong rejection of antidiscrimination law assumptions, namely that the different roles and social roles of women and men have a cultural and social base and it is unnatural, as evidenced by the concept of gender. But many appellants and judgments defend the difference between women and men as if it was informed and legitimated on human nature. Hence gender is considered an ideology, that is, a category of analysis by means of which the reality of true human nature can be concealed or distorted. But these arguments are opposed to recent legal reforms since they are questioning its normative value, by prioritizing certain moral principles against these laws. We are talking about the Organic Law for Effective Equality between Women and Men, the Law on Integrated Protection Measures against Gender Violence and the Law on Education. However their arguments are not fully justified.
Ten years ago, neuroscientists began to study cultural phenomena by using functional MRI. Since then the number of publications in this field, termed cultural neuroscience (CN), has tremendously increased. In these studies, particular concepts of culture are implied, but rarely explicitly discussed. We argue that it is necessary to make these concepts a topic of debate in order to unravel the foundations of CN. From 40 fMRI studies we extracted two strands of reasoning: models investigating universal mechanisms for the formation of cultural groups and habits and, models assessing differences in characteristics among cultural groups. Both strands simplify culture as an inflexible set of traits and specificities. We question this rigid understanding of culture and highlight its hidden evaluative nature.
Conceptual design of an ALICE Tier-2 centre integrated into a multi-purpose computing facility
(2012)
This thesis discusses the issues and challenges associated with the design and operation of a data analysis facility for a high-energy physics experiment at a multi-purpose computing centre. At the spotlight is a Tier-2 centre of the distributed computing model of the ALICE experiment at the Large Hadron Collider at CERN in Geneva, Switzerland. The design steps, examined in the thesis, include analysis and optimization of the I/O access patterns of the user workload, integration of the storage resources, and development of the techniques for effective system administration and operation of the facility in a shared computing environment. A number of I/O access performance issues on multiple levels of the I/O subsystem, introduced by utilization of hard disks for data storage, have been addressed by the means of exhaustive benchmarking and thorough analysis of the I/O of the user applications in the ALICE software framework. Defining the set of requirements to the storage system, describing the potential performance bottlenecks and single points of failure and examining possible ways to avoid them allows one to develop guidelines for selecting the way how to integrate the storage resources. The solution, how to preserve a specific software stack for the experiment in a shared environment, is presented along with its effects on the user workload performance. The proposal for a flexible model to deploy and operate the ALICE Tier-2 infrastructure and applications in a virtual environment through adoption of the cloud computing technology and the 'Infrastructure as Code' concept completes the thesis. Scientific software applications can be efficiently computed in a virtual environment, and there is an urgent need to adapt the infrastructure for effective usage of cloud resources.
Concepts of "Female Inversion" and the "New Woman" in Rhoda Broughton’s "Dear Faustina" (1897)
(2012)
Published in 1897, Rhoda Broughton’s fin de siècle novel "Dear Faustina" took an active part in the discursive production of two cultural figures: the New Woman and the Female Invert. Employing those identity constructs to negotiate conservative anxieties about social change, while at the same time commenting on a range of alternatives to Victorian middle-class lifestyle, the novel is clearly rooted in the discourses of transition that characterised the fin de siècle....
Germany is the focus of this paper, owing to the fact that since 1938 it has had the strictest laws on compulsory schooling worldwide. As a result, homeschooling in Germany has become virtually impossible. There are interesting divergences between policy and practice in the German setting, both in the country’s educational history and present educational problems. The Länder (federal states) have the responsibility for education, and they are taking a much stricter line against homeschoolers than a decade ago, especially by depriving parents of the custody of their homeschooled children at an early stage. The laws relied upon, however, were never intended to deal with such educational matters; they were designed to punish parents who abuse or neglect their children. The present, highly questionable legal action succeeds only because of the consent of state schools, state social welfare offices, and courts. The same laws are not used against the parents of the approximately 250,000 teens who are truant. The functioning of the legal and sociological machinery in Germany is being employed aggressively to stamp out homeschooling, while at the same time it ignores the crucial issue of parents who allow their children to skip school—thus depriving them of an adequate education at home or elsewhere. At the same time, the number of specialists in law and education, as well as politicians and governmental experts who argue in favor of homeschooling is growing, and media reports on homeschooling are much more positive than they were a decade ago.
Prostate cancer is one of the most common tumor diseases worldwide. Often being non-aggressive, prostate tumors in these cases do not need immediate treatment. However, about 20% of diagnosed prostate cancers tend to metastasize and require treatment. Existing diagnostic methods may fail to accurately recognize the transition of a dormant, non-aggressive tumor into highly malignant prostate cancer. Therefore, new diagnostic tools are needed to improve diagnosis and therapy of prostate carcinoma. This review evaluates existing methods to diagnose prostate carcinoma, such as the biochemical marker prostate-specific antigen (PSA), but also discusses the possibility to use the altered expression of integrins and laminin-332 in prostate carcinomas as diagnostic tools and therapeutic targets of prostate cancer.
The complexity resulting from intertwined uncertainties regarding model misspecification and mismeasurement of the state of the economy defines the monetary policy landscape. Using the euro area as laboratory this paper explores the design of robust policy guides aiming to maintain stability in the economy while recognizing this complexity. We document substantial output gap mismeasurement and make use of a new model data base to capture the evolution of model specification. A simple interest rate rule is employed to interpret ECB policy since 1999. An evaluation of alternative policy rules across 11 models of the euro area confirms the fragility of policy analysis optimized for any specific model and shows the merits of model averaging in policy design. Interestingly, a simple difference rule with the same coefficients on inflation and output growth as the one used to interpret ECB policy is quite robust as long as it responds to current outcomes of these variables.
The complexity resulting from intertwined uncertainties regarding model misspecification and mismeasurement of the state of the economy defines the monetary policy landscape. Using the euro area as laboratory this paper explores the design of robust policy guides aiming to maintain stability in the economy while recognizing this complexity. We document substantial output gap mismeasurement and make use of a new model data base to capture the evolution of model specification. A simple interest rate rule is employed to interpret ECB policy since 1999. An evaluation of alternative policy rules across 11 models of the euro area confirms the fragility of policy analysis optimized for any specific model and shows the merits of model averaging in policy design. Interestingly, a simple difference rule with the same coefficients on inflation and output growth as the one used to interpret ECB policy is quite robust as long as it responds to current outcomes of these variables.
Background: In mixed sugar fermentations with recombinant Saccharomyces cerevisiae strains able to ferment D-xylose and L-arabinose the pentose sugars are normally only utilized after depletion of D-glucose. This has been attributed to competitive inhibition of pentose uptake by D-glucose as pentose sugars are taken up into yeast cells by individual members of the yeast hexose transporter family. We wanted to investigate whether D-glucose inhibits pentose utilization only by blocking its uptake or also by interfering with its further metabolism.
Results: To distinguish between inhibitory effects of D-glucose on pentose uptake and pentose catabolism, maltose was used as an alternative carbon source in maltose-pentose co-consumption experiments. Maltose is taken up by a specific maltose transport system and hydrolyzed only intracellularly into two D-glucose molecules. Pentose consumption decreased by about 20 - 30% during the simultaneous utilization of maltose indicating that hexose catabolism can impede pentose utilization. To test whether intracellular D-glucose might impair pentose utilization, hexo-/glucokinase deletion mutants were constructed. Those mutants are known to accumulate intracellular D-glucose when incubated with maltose. However, pentose utilization was not effected in the presence of maltose. Addition of increasing concentrations of D-glucose to the hexo-/glucokinase mutants finally completely blocked D-xylose as well as L-arabinose consumption, indicating a pronounced inhibitory effect of D-glucose on pentose uptake. Nevertheless, constitutive overexpression of pentose-transporting hexose transporters like Hxt7 and Gal2 could improve pentose consumption in the presence of D-glucose.
Conclusion: Our results confirm that D-glucose impairs the simultaneous utilization of pentoses mainly due to inhibition of pentose uptake. Whereas intracellular D-glucose does not seem to have an inhibitory effect on pentose utilization, further catabolism of D-glucose can also impede pentose utilization. Nevertheless, the results suggest that co-fermentation of pentoses in the presence of D-glucose can significantly be improved by the overexpression of pentose transporters, especially if they are not inhibited by D-glucose.
Collection methods and/or habitats sampled influence how many and which species are captured during entomological surveys. Here we compare Coleoptera catches among three survey activities, each using a single collection method, at the same study sites in Great Smoky Mountains National Park, USA. Activities included: short-term flight intercept trapping (FITs); sifting/Berlese funneling of leaf litter and extremely decayed downed coarse woody debris; and using emergence chambers containing coarse woody debris of various decay classes. In total, 2472 adult beetle specimens, representing 217 lowest identifiable taxa within 164 genera and 42 families, were collected during the FIT survey. Each survey activity yielded more than 2000 specimens, and a combined total of 413 species was collected. A combination of all surveys yielded the highest species richness when normalized for number of specimens indicating that variation of habitat and/or collection method significantly increases species richness. Of single surveys the FIT survey had the highest absolute species richness (217) and the highest richness when normalized for number of specimens. Species overlap among survey activities was low (Sorensen’s quotient of similarity was 0.20–0.27), which showed that each was about equally dissimilar from all others. Overlap of catch between FITs and emergence chambers was too low to justify substitution of emergence surveys with the FIT survey protocol used when attempting to collect saproxylic Coleoptera.
The four subunit (SU) aa3 cytochrome c oxidase (CcO) from Paracoccus denitrificans is one of the terminal enzymes of the respiratory chain. It uses electrons from cytochrome c to reduce molecular oxygen to water. Its binuclear active center, residing in SU I, contains hemeÊa3 and CuB, the latter being liganded by three histidine residues. Apart from its oxygen reductase activity, the protein possesses a peroxidase and a catalase activity.
To compare variants and the wild type (WT) protein in a more stringent way, a recombinant (rec.) WT CcO was constructed, carrying the gene for SUÊI on a low copy number plasmid. This rec. WT showed, as expected, no difference in oxygen reductase activity compared to the American Type Culture Collection (ATCC) WT CcO but surprisingly its catalase activity was increased by a factor of 20. The potential overproduction of SUÊI due to plasmid coding and the resulting deficiency in metal inserting chaperones might impair the correct insertion of hemeÊa3 and CuB because of a deficiency in metal inserting chaperones. This in turn might lead to differences in side chain orientation and to changes in the water network. However, slight changes might cause an increased accessibility of the active center for hydrogen peroxide, resulting in an increased catalase activity. The availability of chaperones and therefore the proposed structural reasons for the difference was improved by cloning the genes for the two metal inserting chaperones CtaG and Surf1c on the same plasmid together with SUÊI. This new rec. WT CcO showed in fact a reduced catalase activity. Another WT with a deletion in the chromosomal second, non expressing gene of SU I was analysed to prove plasmid coding as the reason for the difference of the ATCC WT and the rec. WT. This strain showed an increased kcat of the catalase activity as well, additionally pointing to a regulatory effect of the non expressed gene for SU I in the chromosome. To fathom the structural difference of the increased catalase activity, differential scanning calorimetry was used, but no significant difference in thermal stability between the ATCC WT CcO and the rec. WT CcO was detected. However, upon aging, the thermal stability of the rec. WT CcO declined faster than that of the ATCC WT CcO pointing to a decreased structural stability of the rec. WT CcO.
To characterize the catalase reaction, several known inhibitors were used to probe the contribution of the different metal cofactors in the catalase reaction. In addition variants in aromatic amino acids near the active center were constructed to conclude on a possible reaction mechanism of the catalase activity of CcO. These variants in combination with the wild type forms were analysed for radical signals by EPR-spectroscopy. A radical relevant for the catalase reaction of CcO was found in the F-intermediate of all variants and all wild type forms. This narrow 12 G radical signal was assigned to a porphyrine radical probably involved in the catalase reaction of CcO. Moreover, gas chromatography-mass spectrometry measurements were used to analyse isotopically labelled oxygen produced in the catalase reaction.
As a result of these experiments, a reaction cycle of the catalase activity of CcO is postulated and the structural difference between the ATCC and rec. WT CcO is outlined. The catalase activity appears to be a true catalase activity and not a "pseudocatalase" activity.
The community within extremely decayed downed coarse woody debris, here referred to as decay class V (CWD5), has never been systematically sampled. The presumption has been that rotten wood is eventually overrun by surrounding soil and litter inhabitants. Leaf litter and CWD5 were sampled for Coleoptera with a sifting/ Berlese technique at three primary and three secondary forest sites in Great Smoky Mountains National Park, Tennessee, USA, during fall 2006 and spring 2007. A total of 4261 adult beetle specimens, representing 216 lowest identifiable taxa within 159 genera and 28 families, were collected. Sixty-six species (31%) were represented by single individuals. Many more specimens (3471) and species (170) were collected from leaf litter than from CWD5 (790 and 111, respectively) but species accumulation curves showed that species richness was not significantly different between the two habitats. Eight species were significantly associated with CWD5, and 40 species were significantly associated with leaf litter. Species richness was significantly higher in secondary forest than primary forest, but more species were significantly associated with primary than secondary forest. Species richness was significantly higher in spring than fall. Notes on the biology and photographs of the 59 species represented by 10 or more specimens are given to provide an atlas of common eastern U.S. beetle species found in these habitats. Overall CWD5 is a distinct but overlooked habitat that may harbor numerous undescribed species or species considered rare.
Bryophytes (liverworts, mosses and hornworts) hold the basal most position among extant land plants. The present study deals with comparative analysis of available mitochondrial genomes of bryophytes using bioinformatics tools. These mitochondrial genomes belong to 2 liverworts, 1 moss and 2 hornworts. The analysis is based on multiple genome analysis through whole proteome comparison to detect conservation between mitochondrial genomes of bryophytes.
Coleoptera species composition and succession in downed woody debris habitats are poorly known in eastern North America. A photoeclector emergence chamber was used to concentrate Coleoptera that emerged from various decay classes of fine and coarse woody debris (FWD and CWD, respectively) collected in primary and secondary forest sites in Great Smoky Mountains National Park, Tennessee, USA. A total of 5673 adult beetle specimens, representing 305 lowest identifiable taxa within 227 genera and 51 families, was collected. One hundred fifteen species (38%) were represented by single individuals. Many more specimens and species were collected from CWD (4129 and 247, respectively) than from FWD (1544 and 162, respectively), but species richness accumulation curves were not significantly different. Many more specimens but an equal number of species were collected from primary forest (3347 and 207, respectively) than from secondary forest (2326 and 207, respectively). Species accumulation curves indicated higher richness in secondary forests. Based on a subset of 71 species represented by 10 or more specimens, 27 species were associated with fresh fine woody debris, 11 species with weathered fine woody debris, four with coarse woody debris decay class I, 14 with coarse woody debris decay class II, and eight with coarse woody debris decay class III–IV. Sixteen species were associated with secondary forests, whereas 28 species were associated with primary forests. Coarse woody debris decay class II taken in primary forests had highest absolute species richness with 156 species. In coarse woody debris species overlap decreased with increased difference in decay indicating faunal succession. Published works related to the study of the ecology of downed woody material are briefly summarized. Recommendations on developing a database of legacy trees for future researchers are given. Notes on the biology and photographs of the 71 species represented by 10 or more specimens are given to provide an atlas of eastern U.S. beetle species most commonly encountered in these habitats.
Species may become vulnerable because of a reduction of habitat, leading to reduction of population sizes and an increase in geographic isolation between populations, leading to genetic drift that may result in reduced reproductive fitness. The restricted sedge Gahnia insignis S.T. Blake (family Cyperaceae), occurring in isolated pockets in north-east New South Wales and Queensland, was compared to a closely related, sympatric, common and widespread Gahnia clarkei Benl for flowering phenology and reproductive success. Flowering patterns, examination of pollen, fertilisation and embryo development and seed-ovule ratios show Gahnia clarkei has every indication of successful sexual reproduction, but that Gahnia insignis appears to reproduce mostly by vegetative means, with an occasional sexual event. This was due to the rarity of pollination opportunities, and to poor pollen viability and pollen quantity, resulting in a much lower seed-ovule ratio than Gahnia clarkei. The additional high level of vegetative reproduction in Gahnia insignis suggests it may be largely clonal in Nightcap National Park. A genetic study of the whole distribution would add knowledge of the species genetic diversity and differentiation between populations.
This is a dense, erudite collection of finely crafted poems that powerfully reflect on vices such as war, bad governance, deforestation, dissipation, greed, oppression and cruelty. The poems also tackle other important phenomena of life such as love, anxiety, weather, time, politics, morality, economics, justice, culture and the environment. The virtue of these finely tuned poems does not only lie in their philosophical questioning, but their artistic merit and audacious reflection of issues pertinent in human life of all ages. While some of the poems provoke amusement and others tears, the corpus of the collection educates through entertainment. The poetry penetrates into the greater depths of the public's psyche to appraise, query, empty and expose their concerns in such a manner that should hopefully make those who cause or ignite human tribulations to rethink their actions and those haunted by the same to stay vigilant.
"Community and law approach" provides an illuminating insight into alternative legal orderings within a social unit. The comprehensiveness of legal systems within a community or a social unit, provides a suitable basis for a structural framework of alternative legal systems or Legal Pluralism, which is missing in the discourse on Legal Pluralism. "Identifying the locus of law within a community", provides us with an indication on how autopoetic a legal system can be within a social unit, taking into account the social rootedness of legal norms.
Abstract/Keywords: Theory of communicative action, ontology of the sentence, systems, subsystems, role, function, crime of breach of duty, compensation, general and special prevention, rule of law, breach of communicative rationality, institutional rivalry and competition for organization, lord of the fact, the duty of guarantor, facticity and validity, counterfactual assertion, public use of reason, prosecution, transcendental ego, self, idealism, voyage, cognitive subject, object of knowledge, hermeneutics of criminal conduct and public servant
A new era in experimental nuclear physics has begun with the start-up of the Large Hadron Collider at CERN and its dedicated heavy-ion detector system ALICE. Measuring the highest energy density ever produced in nucleus-nucleus collisions, the detector has been designed to study the properties of the created hot and dense medium, assumed to be a Quark-Gluon Plasma.
Comprised of 18 high granularity sub-detectors, ALICE delivers data from a few million electronic channels of proton-proton and heavy-ion collisions.
The produced data volume can reach up to 26 GByte/s for central Pb–Pb
collisions at design luminosity of L = 1027 cm−2 s−1 , challenging not only the data storage, but also the physics analysis. A High-Level Trigger (HLT) has been built and commissioned to reduce that amount of data to a storable value prior to archiving with the means of data filtering and compression without the loss of physics information. Implemented as a large high performance compute cluster, the HLT is able to perform a full reconstruction of all events at the time of data-taking, which allows to trigger, based on the information of a complete event. Rare physics probes, with high transverse momentum, can be identified and selected to enhance the overall physics reach of the experiment.
The commissioning of the HLT is at the center of this thesis. Being deeply embedded in the ALICE data path and, therefore, interfacing all other ALICE subsystems, this commissioning imposed not only a major challenge, but also a massive coordination effort, which was completed with the first proton-proton collisions reconstructed by the HLT. Furthermore, this thesis is completed with the study and implementation of on-line high transverse momentum triggers.
This paper presents epistemological and methodological problems found in work on the subgrouping of Sino-Tibetan languages and the reconstruction of features of the languages. A key problem is the lack of an accepted standard for judging this work, one that can stand up to statistical evaluation. An alternative methodology that involves using fixed sets of features to give us the statistical probability of common origin is suggested.
This present comment suggests an amendment to the proposal for a directive of the European Parliament and of the Council, establishing a framework for the recovery and resolution of credit institutions and investment firms. The current proposal focuses on bail-in, but does not sufficiently take into account the pressure exerted on central bankers, supervisors and politicians by the fear of interbank contagion. The only way out of this hold-up type of situation can be found in bail-in bonds. Bail-in bonds are dedicated loss taking debt instruments, whose status of being first in line if it comes to default is clearly communicated from day one.
One-photon and multi-photon absorption, spontaneous and stimulated photon emission, resonance Raman scattering and electron transfer are important molecular processes that commonly involve combined vibrational-electronic (vibronic) transitions. The corresponding vibronic transition profiles in the energy domain are usually determined by Franck-Condon factors (FCFs), the squared norm of overlap integrals between vibrational wavefunctions of different electronic states. FC profiles are typically highly congested for large molecular systems and the spectra usually become not well-resolvable at elevated temperatures. The (theoretical) analyses of such spectra are even more difficult when vibrational mode mixing (Duschinsky) effects are significant, because contributions from different modes are in general not separable, even within the harmonic approximation. A few decades ago Doktorov, Malkin and Man'ko [1979 J. Mol. Spectrosc. 77, 178] developed a coherent state-based generating function approach and exploited the dynamical symmetry of vibrational Hamiltonians for the Duschinsky relation to describe FC transitions at zero Kelvin. Recently, the present authors extended the method to incorporate thermal, single vibronic level, non-Condon and multi-photon effects in energy, time and probability density domains for the efficient calculation and interpretation of vibronic spectra. Herein, recent developments and corresponding generating functions are presented for single vibronic levels related to fluorescence, resonance Raman scattering and anharmonic transition.
The ALICE Collaboration has made the first measurement at the LHC of J/ψ photoproduction in ultra-peripheral Pb–Pb collisions at sNN=2.76 TeV. The J/ψ is identified via its dimuon decay in the forward rapidity region with the muon spectrometer for events where the hadronic activity is required to be minimal. The analysis is based on an event sample corresponding to an integrated luminosity of about 55 μb−1. The cross section for coherent J/ψ production in the rapidity interval −3.6<y<−2.6 is measured to be dσJ/ψcoh/dy=1.00±0.18(stat)−0.26+0.24(syst) mb. The result is compared to theoretical models for coherent J/ψ production and found to be in good agreement with those models which include nuclear gluon shadowing.
A subgroup of pediatric acute T-lymphoblastic leukemia (T-ALL) was characterized by a gene expression profile comparable to that of early T-cell precursors (ETPs) with a highly unfavorable outcome. We have investigated clinical and molecular characteristics of the ETP-ALL subgroup in adult T-ALL. As ETP-ALL represents a subgroup of early T-ALL we particularly focused on this cohort and identified 178 adult patients enrolled in the German Acute Lymphoblastic Leukemia Multicenter studies (05/93–07/03). Of these, 32% (57/178) were classified as ETP-ALL based on their characteristic immunophenotype. The outcome of adults with ETP-ALL was poor with an overall survival of only 35% at 10 years, comparable to the inferior outcome of early T-ALL with 38%. The molecular characterization of adult ETP-ALL revealed distinct alterations with overexpression of stem cell-related genes (BAALC, IGFBP7, MN1, WT1). Interestingly, we found a low rate of NOTCH1 mutations and no FBXW7 mutations in adult ETP-ALL. In contrast, FLT3 mutations, rare in the overall cohort of T-ALL, were very frequent and nearly exclusively found in ETP-ALL characterized by a specific immunophenotype. These molecular characteristics provide biologic insights and implications with respect to innovative treatment strategies (for example, tyrosine kinase inhibitors) for this high-risk subgroup of adult ETP-ALL.
Climate and subsequent environmental changes are regarded as one driver of species evolution. Against this background the present study investigates the evolutionary history of the mammalian family Bovidae (Cetartiodactyla, Mammalia), today the most species-rich family of large herbivores on the African continent. Temporal and spatial patterns in that group’s evolution are the focus of the present study and were investigated using methods and data deriving from multiple disciplines (palaeontology, genetics, climatology, conservation biology). The results serve as a validation of macroevolutionary hypotheses of species evolution.
A major proportion of African mammalian fossils can be assigned to that family. Due to their morphological adaptations, bovid species are highly indicative of their habitats. Hence, bovids are of great importance for paleontology. However, a strong taphonomic bias is present in the fossil record of bovids, favoring large and arid- adapted species. Molecular phylogenies of extant species and species distribution modelling combined with climate reconstructions can help to overcome these limitations.
A molecular phylogeny, based on the cytochrome b gene of 136 bovid species served as basis for analysis of temporal patterns. Divergence events were dated using the relaxed molecular clock approach. The tree was time calibrated at 30 nodes using information inferred from the fossil record. Lineage-Through-Time plots and the respective statistical analyses reveal detailed temporal patterns in the evolutionary history of tribes and groups combining arid- and humid-adapted tribes. The resulting pattern shows three distinct phases. Phase 1 (P1) is dominated by speciation events within the humid group, while the second phase (P2) is marked by a dominance of speciation within the arid group. The switch in diversification rates (BDS) from P1 to P2 is dated to 2.8 million years ago. The third phase (P3) shows low diversification rates for all groups, starting around 1.4 million year ago and culminates in a significantly reduced diversification rate for the complete family at 0.8 million years ago. Both transitions are contemporaneous with global climate changes and turnover events in fossil faunal communities.
To investigate the impact of climate changes onto the habitat availability within the last 3 million years and its putative influence on diversification rates, the species distribution modeling method was applied. For 85 African species and subspecies the climate niches were established and grouped into 5 climate-groups based on their climate preferences. For each group the available habitat for the period before and after the BDS was calculated on continental scale using reconstructed climate scenarios. To evaluate the modeled habitat distributions, regional analyses were performed in test areas surrounding well studied fossil sites (Laetoli, Olduvai, Chiwondo Beds, Lothagam, Koobi Fora, West Turkana, Swartkrans, Sterkfontain und Toros-Menalla). Habitat profiles (HP) permitted the comparison of the model based habitat reconstruction with the interpretations of classic paleontological reconstruction. The validity of the habitat modeling has been shown in particular for East African test areas. The reconstructions for the northern and southern fossil sites does not support the modeled habitats in these areas. Yet, the method of habitat- profiling may serve as suitable tool for environmental reconstruction of areas lacking sufficient paleontological material. A comparison of habitat availability before and after the BDS on continental scale identified a significant loss of habitat for humid adapted groups (7-22%) and habitat gain for arid adapted groups (19-173%). The climatically intermediate group experiences a tremendous gain of habitat (3366%). The greatest environmental change was modeled for East Africa, initiated by a progressive regional aridification.
In addition to the distribution modeling for past climate conditions, the geographical distribution was modeled for the future, i.e. for climate scenarios representing the years 2050 and 2080 under a putative climate change scenario (global surface warming). It was shown that in particular the arid groups have to expect a remarkable loss of habitat (41-76%), while a gain of available habitat can be expected for the humid adapted groups (114-577%). The climatically intermediate group suffers the strongest habitat loss (85%). Regions with locally stable climate conditions were detected and may serve as potential refugia and are already today known as Africa’s hot spots of biodiversity.
The results show a positive correlation of high diversification rates and increasing habitat availability. None of the tested speciation hypotheses taken alone explains the observations (e.g., Turnover-pulse Hypothesis, Relay Model). A major element in these hypotheses is the passive fragmentation of populations induced by unfavorable climate changes. In contrast, the Periodic Model (Grubb 1999) considers natural, periodically recurring climate changes and moreover, the active dispersal of individuals and resulting founder events. I added the effect of a superimposed directed climate trend – like the progressive aridification since the late Pliocene in Africa – which leads to a bias in the proportion and probability towards leading edge effects. This Directed Periodic Model explains the patterns found in the evolution of Bovidae.
The combination of a molecular phylogeny and species distribution modeling, together with information inferred from the fossil record, reveals remarkable temporal and spatial patterns in the evolution of bovids, and helps overcome the limitations of the fossil record. The present study highlights the importance of active dispersal and founder populations in speciation processes. A point widely unattended in speciation hypotheses. The fully dated molecular phylogeny is the most densely sampled tree for the family Bovidae to date and may serve as a framework for a connection of present and future population studies, permitting the connection of medium-scale with long- term effects induced by climate and environmental changes.
Chinese is often taken as a prime example of an isolating language. Most relation marking takes the form of particles rather than affixes or inflections. Possibly relevant to the facts that are presented below, Chinese has been argued to not have grammaticalized the sort of pivot constructions normally associated with grammatical relations. That is, it has been argued to not have any particular alignment, as there are no grammatical relations, and the clause pattern is simply topic-comment (Chao 1968, Lü 1979, LaPolla 1993, 1995, 2009; LaPolla & Poa 2005, 2006). We will first talk more generally about structures found in Sino-Tibetan languages, and then focus on Modern Mandarin Chinese.
Background. Leukotriene B4 (LTB4), a proinflammatory lipid mediator correlates well with the acute phase of Acute Respiratory Distress Syndrome (ARDS). Therefore, LTB4-levels were investigated to determine whether they might be a useful clinical marker in predicting pulmonary complications (PC) in multiply traumatized patients. Methods: Plasma levels of LTB4 were determined in 100 patients on admission (ED) and for five consecutive days (daily). Twenty healthy volunteers served as control. LTB4-levels were measured by ELISA. Thirty patients developed PC (pneumonia, respiratory failure, acute lung injury (ALI), ARDS, pulmonary embolism) and 70 had no PC (ØPC). Results. LTB4-levels in the PC-group [127.8 pg/mL, IQR: 104–200pg/ml] were significantly higher compared to the ØPC-group on admission [95.6 pg/mL, IQR: 55–143 pg/mL] or control-group [58.4 pg/mL, IQR: 36–108 pg/mL]. LTB4 continuously declined to basal levels from day 1 to 5 without differences between the groups. The cutoff to predict PC was calculated at 109.6 pg/mL (72% specificity, 67% sensitivity). LTB4 was not influenced by overall or chest injury severity, age, gender or massive transfusion. Patients with PC received mechanical ventilation for a significantly longer period of time, and had prolonged intensive care unit and overall hospital stay. Conclusion. High LTB4-levels indicate risk for PC development in multiply traumatized patients
Astrid Deuber-Mankowsky's paper 'Cinematographic Aesthetics as Subversion of Moral Reason in Pasolini's Medea' explores the 1969 film "Medea". Pasolini's Medea, masterfully played by Maria Callas, betrays her homeland and her origin, stabs both her children, sets her house on fire, and dispossesses Jason of his sons' corpses. But Deuber-Mankowsky argues that it is ultimately not these acts that render the film particularly disturbing and disconcerting, but, rather, the fact that the spectator is left behind in suspension precisely because Medea cannot be easily condemned for her acts. Pasolini's film and its cinematographic aesthetics thereby not only subvert the projection of Medea into the prehistorical world of madness and perversion, but also undermine belief in the validity of the kind of moral rationality developed and constituted in an exemplary way by Immanuel Kant in his "Critique of Practical Reason". In particular, Pasolini seems to relate conceptually to Nietzsche's artistic-philosophical transfiguration of Dionysus and to accuse belief in a world of reasons of failing to grasp the groundlessness, irrationality, or even a-rationality of reason itself.
I first encountered the work of Miriam Hansen as a graduate student in the mid-1990s when her book Babel and Babylon was the talk of the (at that time still fairly modest) film studies town – even though it was sitting somewhat uneasily on the fence. In fact, it was this position beyond the canonical that made the book so attractive in the first place. It did not fit into the raging debate of that time between psychosemiotics and neo-formalism, nor did it offer the (often too schematic and naive) way out within the cultural studies paradigm of empowering the individual or sub-culturally constituted groups.
Membrane-embedded β-barrel proteins are found in the outer membranes (OM) of Gram-negative bacteria, mitochondria and chloroplasts. In eukaryotic cells, precursors of these proteins are synthesized in the cytosol and have to be sorted to their corresponding organelle. Currently, the signal that ensures their specific targeting to either mitochondria or chloroplasts is ill-defined. To address this issue, we studied targeting of the chloroplast β-barrel proteins Oep37 and Oep24. We found that both proteins can be integrated in vitro into isolated plant mitochondria. Furthermore, upon their expression in yeast cells Oep37 and Oep24 were exclusively located in the mitochondrial OM. Oep37 partially complemented the growth phenotype of yeast cells lacking Porin, the general metabolite transporter of this membrane. Similarly to mitochondrial β-barrel proteins, Oep37 and Oep24 expressed in yeast cells were assembled into the mitochondrial OM in a pathway dependent on the TOM and TOB complexes. Taken together, this study demonstrates that the central mitochondrial components that mediate the import of yeast β-barrel proteins can deal with precursors of chloroplast β-barrel proteins. This implies that the mitochondrial import machinery does not recognize signals that are unique to mitochondrial β-barrel proteins. Our results further suggest that dedicated targeting factors had to evolve in plant cells to prevent mis-sorting of chloroplast β-barrel proteins to mitochondria.
Since the availability of first complete DNA sequence of chloroplast genome of Marchantia polymorpha several studies to determine the structure and organization of chloroplast genomes of various plant groups have been made. However the lineage sampling of bryophytes are poorly represented in complete chloroplast genome sequences (only three liverworts, two mosses and one hornwort). This review presents features of sequenced chloroplast genomes of bryophytes.
Bryophytes (mosses, liverworts and hornworts) are the most basal lineages among extant land plants. However, there is controversy regarding their monophyletic or paraphyletic origin. Moreover, the most basal group of bryophytes also remains questionable. Due to this it is a matter of debate which lineage of bryophytes acts as transition link between bryophytes and pteridophytes. In order to resolve these issues we conducted a bioinformatics analysis on available chloroplast genomes of 1 green alga, 5 bryophytes, 4 pteridophytes, and 6 gymnosperms. Our study is based on multiple genome analysis through whole proteome comparison. The higher number of orthologous identified in Anthoceros (a hornwort), in comparison to other bryophytes considered, against all pteridophytes strongly support hornworts as transition link between bryophytes and pteridophytes.
Chioniso and Other Stories
(2012)
In this new collection, Chioniso and other stories, we are once again reminded how Shimmer Chinodya mines his experience for nuggets. Playing with his doppelganger, Godfrey, he looks back on life in Harare, and in Zimbabwe, over the last decade, exploring it from a familial perspective. How does a father cope with a rebellious daughter or a wife he perceives as wayward? How does one mediate traditional gender roles? What to do when status in the form of a car undermines the stability of a marriage? How does one manage a friendship with a new farmer? What moral compromises are demanded by new wealth and political cronyism? And what is the effect of religion on our lives? Have we become more caring and compassionate, or does piety provide a mask, to disguise greed and ambition, and justify a contempt for the poor? This collection of stories will make you laugh, but it will also challenge you to reconsider what it means to be Zimbabwean in the 21st century.
Cytokines play an important role in ischemic injury and repair. However, little is known about their prognostic value in cardiovascular disease. The aim of this study was to investigate the prognostic importance of chemokines CCL3/MIP-1α, CCL5/RANTES and CCL18/PARC for the risk of future cardiovascular events in patients with acute coronary syndromes (ACS). Baseline levels of CCL3/MIP-1α, CCL5/RANTES and CCL18/PARC were determined in ACS patients from the Bad Nauheim ACS II registry (n = 609). During the following 200 days, patients were monitored for the occurrence of fatal and non-fatal cardiovascular events. Patients with CCL3/MIP1α, CCL5/RANTES and CCL18/PARC concentrations in the highest tertile were associated with an increased risk of a fatal event during follow-up (HR: 2.19, 95%CI: 1.04–4.61 for CCL3/MIP1α, HR: 3.45, 95%CI: 1.54–7.72 for CCL5/RANTES and HR: 3.14, 95%CI: 1.33–7.46 for CCL18/PARC). This risk was highest for patients with all three biomarkers concentrations in the upper tertile (HR: 2.52, 95%CI: 1.11–5.65). Together with known risk predictors of cardiovascular events, CCL3/MIP-1α, CCL5/RANTES and CCL18/PARC combined improved the c-statistics from 0.74 to 0.81 (p = 0.007). In conclusion, CCL3/MIP-1α, CCL5/RANTES and CCL18/PARC are independently associated with the risk of short-term mortality in ACS patients. Combining all three biomarkers further increased their prognostic value.
This study demonstrates that alkaline earth elements in enamel of hippopotamids, in particular Ba and Sr, are tracers for water provenance and hydrochemistry in terrestrial settings. The studied specimens are permanent premolar and molar teeth found in modern and fossil lacustrine sediments of the Western Branch of the East African Rift system (Lake Kikorongo, Lake Albert, and Lake Malawi) and from modern fluvial environments of the Nile River.
Concentrations in enamel vary by two orders of magnitude for Ba (120–9336 μg g−1) as well as for Sr (9–2150 μg g−1). The variations are partially induced during post-mortem alteration and during amelogenesis, but the major contribution originates ultimately from the variable water chemistry in the habitats of the hippopotamids which is controlled by the lithologies and weathering processes in the watershed areas. Amelogenesis causes a distinct distribution of MgO, Ba and Sr in modern and fossil enamel, in that element concentrations increase along profiles from the outer rim towards the enamel–dentin junction by a factor of 1.3–1.9. These elements are well correlated in single specimens, thus suggesting that their distribution is determined by a common, single process, which can be described by closed system Rayleigh crystallization of bioapatite in vivo.
Enamel from most hippopotamid specimens has Sr/Ca and Ba/Ca which are typical for herbivores. However, Ba/Sr ranges from 0.1 to 3 and varies on spatial and temporal scales. Thus, Sr concentrations and Ba/Sr in enamel differentiate between habitats having basaltic mantle rocks or Archean crustal rocks as the ultimate sources of Sr and Ba. This provenance signal is modulated by climate change. In Miocene to Pleistocene enamel from the Lake Albert region, Ba/Sr decreases systematically with time from 2 to 0.5. This trend can be correlated with changes in climate from humid to arid, in vegetation from C3 to C4 biomass as well as with increasing evaporation of the lake water. The most plausible explanation is that Ba mobility decreased with increasing aridification due to preferential deposition with clay and Fe-oxide-hydroxide or barite on the watershed of Lake Albert.
For reconstructing environmental change in terrestrial realms the geochemistry of fossil bioapatite in bones and teeth is among the most promising applications. This study demonstrates that alkaline earth elements in enamel of Hippopotamids, in particular Ba and Sr are tracers for water provenance and hydrochemistry. The studied specimens are molar teeth from Hippopotamids found in modern and fossil lacustrine settings of the Western Branch of the East African Rift system (Lake Kikorongo, Lake Albert, and Lake Malawi) and from modern fluvial environments of the Nile River.
Concentrations in enamel vary by ca. two orders of magnitude for Ba (120–9336 μg g−1) as well as for Sr (9–2150 μg g−1). Concentration variations in enamel are partly induced during post-mortem alteration and during amelogenesis, but the major contribution originates from the variable water chemistry in the habitats of the Hippopotamids which is dominated by the lithologies and weathering processes in the watershed areas. Amelogenesis causes a distinct distribution of Ba and Sr in modern and fossil enamel, in that element concentrations increase along profiles from the outer rim towards the enamel-dentin junction by a factor of 1.3–1.5. These elements are well correlated with MgO and Na2O in single specimens, thus suggesting that their distribution is determined by a common, single process. Presuming that the shape of the tooth is established at the end of the secretion process and apatite composition is in equilibrium with the enamel fluid, the maturation process can be modeled by closed system Rayleigh crystallization.
Enamel from many Hippopotamid specimens has Sr/Ca and Ba/Ca which are typical for herbivores, but the compositions extend well into the levels of plants and carnivores. Within enamel from single specimens these element ratios covary and provide a specific fingerprint of the Hippopotamid habitat. All specimens together, however, define subparallel trends with different Ba/Sr ranging from 0.1 to 3. This ratio varies on spatial and temporal scales and traces provenance signals as well as the fractionation of the elements in the hydrological cycle. Thus, Sr concentrations and Ba/Sr in enamel differentiate between habitats having basaltic or Archean crustal rocks as the ultimate sources of Sr and Ba. The provenance signal is modulated by climate change. In Miocene to Pleistocene enamel from the Lake Albert region, Ba/Sr decreases systematically with time from about 2 to 0.5. This trend can be correlated with changes in climate from humid to arid in vegetation from C3 to C4 biomass as well as with increasing evaporation of the lake water. The most plausible explanation is that with time, Ba mobility decreased relative to that of Sr. This can arise if preferential adsorption of Ba to clay and Fe-oxide-hydroxide is related to increasing aridification. Additionally, weathering solutions and lake water can become increasingly alkaline and barite becomes stable. In this case, Ba will be preferentially deposited on the watershed of Lake Albert and rivers with low Ba/Sr will feed the habitats of the Hippopotamids.
Bioapatite in mammalian teeth is readily preserved in continental sediments and represents a very important archive for reconstructions of environment and climate evolution. This project provides a comprehensive data base of major, minor and trace element and isotope tracers for tooth apatite using a variety of microanalytical techniques. The aim is to identify specific sedimentary environments and to improve our understanding on the interaction between internal metabolic processes during tooth formation and external nutritional control and secondary alteration effects. Here, we use the electron microprobe to determine the major and minor element contents of fossil and modern molar enamel, cement and dentin from Hippopotamids. Most of the studied specimens are from different ecosystems in Eastern Africa, representing modern and fossil lacustrine (Lake Kikorongo, Lake Albert, and Lake Malawi) and modern fluvial environments of the Nile River system. Secondary alteration effects - in particular FeO, MnO, SO3 and F concentrations – are 2 to 10 times higher in fossil than in modern enamel; the secondary enrichment of these components in fossil dentin and cement is even higher. In modern and fossil enamel, along sections perpendicular to the enamel-dentin junction (EDJ) or along cervix-apex profiles, P2O5 and CaO contents and the CaO/P2O5 ratios are very constant (StdDev ∼1%). Linear regression analysis reveals tight control of the MgO (R2∼0.6), Na2O and Cl variation (for both R2>0.84) along EDJ-outer enamel rim profiles, despite large concentration variations (40% to 300%) across the enamel. These minor elements show well defined distribution patterns in enamel, similar in all specimens regardless of their age and origin, as the concentration of MgO and Na2O decrease from the enamel-dentin junction (EDJ) towards the outer rim, whereas Cl displays the opposite trend. Fossil enamel from Hippopotamids which lived in the saline Lake Kikorongo have a much higher MgO/Na2O ratio (∼1.11) than those from the Neogene fossils of Lake Albert (MgO/Na2O∼0.4), which was a large fresh water lake like those in the western Branch of the East African Rift System today. Similarly, the MgO/Na2O ratio in modern enamel from the White Nile River (∼0.36), which has a Precambrian catchment of dominantly granites and gneisses and passes through several saline zones, is higher than that from the Blue Nile River, whose catchment is the Neogene volcanic Ethiopian Highland (MgO/Na2O∼0.22). Thus, particularly MgO/Na2O might be a sensitive fingerprint for environments where river and lake water have suffered strong evaporation. Enamel formation in mammals takes place at successive mineralization fronts within a confined chamber where ion and molecule transport is controlled by the surrounding enamel organ. During the secretion and maturation phases the epithelium generates different fluid composition, which in principle, should determine the final composition of enamel apatite. This is supported by co-linear relationships between MgO, Cl and Na2O which can be interpreted as binary mixing lines. However, if maturation starts after secretion is completed, the observed element distribution can only be explained by equilibration of existing and addition of new apatite during maturation. It appears the initial enamel crystallites precipitating during secretion and the newly formed bioapatite crystals during maturation equilibrate with a continuously evolving fluid. During crystallization of bioapatite the enamel fluid becomes continuously depleted in MgO and Na2O, but enriched in Cl which results in the formation of MgO, and Na2O-rich, but Cl-poor bioapatite near the EDJ and MgO- and Na2O-poor, but Cl-rich bioapatite at the outer enamel rim. The linkage between lake and river water compositions, bioavailability of elements for plants, animal nutrition and tooth formation is complex and multifaceted. The quality and limits of the MgO/Na2O and other proxies have to be established with systematic investigations relating chemical distribution patterns to sedimentary environment and to growth structures developing as secretion and maturation proceed during tooth formation.
nefficient intracellular protein trafficking is a critical issue in the pathogenesis of a variety of diseases and in recombinant protein production. Here we investigated the trafficking of factor VIII (FVIII), which is affected in the coagulation disorder hemophilia A. We hypothesized that chemical chaperones may be useful to enhance folding and processing of FVIII in recombinant protein production, and as a therapeutic approach in patients with impaired FVIII secretion. A tagged B-domain-deleted version of human FVIII was expressed in cultured Chinese Hamster Ovary cells to mimic the industrial production of this important protein. Of several chemical chaperones tested, the addition of betaine resulted in increased secretion of FVIII, by increasing solubility of intracellular FVIII aggregates and improving transport from endoplasmic reticulum to Golgi. Similar results were obtained in experiments monitoring recombinant full-length FVIII. Oral betaine administration also increased FVIII and factor IX (FIX) plasma levels in FVIII or FIX knockout mice following gene transfer. Moreover, in vitro and in vivo applications of betaine were also able to rescue a trafficking-defective FVIII mutant (FVIIIQ305P). We conclude that chemical chaperones such as betaine might represent a useful treatment concept for hemophilia and other diseases caused by deficient intracellular protein trafficking.
The manuscript name Chelifer longimanus Kollar, 1848, most often cited as Obisium longimanum Kollar, was first introduced in a note by Kollar (1848) that has been overlooked in the taxonomic literature on pseudoscorpions. No description or indication has been associated with this name, which is therefore a nomen nudum. It corresponds to the valid pseudoscorpion species Neobisium spelaeum (Schiödte, 1847), having been found at one of the type localities of the latter (Postojna Cave, Slovenia). Two specimens originally identified as O. longimanum (probably by V. Kollar) are present in the collections of the Naturhistorisches Museum Wien.
Sons of revolutionaries, a classic Huck Finn/Tom Sawyer duo must grow up and find themselves when President-for-Life Robert Mugabe tightens his grip on white landowners and plunges Zimbabwe into anarchy. Julie Wakeman-Linn's striking debut-part buddy road trip, part familial dramedy--focuses on two racially blended families as they outwit the world of diplomats, ex-pats, safari tourists, street rats, border guards, and the mercurial landscape. The result is an electrifying video capture of Africa in 1997 overflowing with intense color, tenacious characters, and riotous details.
Structural characterization of a polymethylsilsesquioxane (PMSQ) and a DT-type methyl silicone resin (MeDT) has been carried out by various instrumental analyses including GPC, NMR, gas chromatography, and gas chromatography-mass spectrometry. Although the PMSQ had a Mw around 5000, the resin contained a significant amount of low molecular weight species consisting of T2 [MeSi(OH)O2/2] and T3 [MeSiO3/2] units, ranging from T34T23 to T38T22 including many isomers. One isomer of T36T22 was isolated of which structure was determined as a cage structure. The species are supposed to consist mainly of cyclotetra- and cyclopentasiloxanes, but presence of strained rings such as cyclotrisiloxane rings also was suggested. In MeDT, species in which the T2 units in the molecules from PMSQ is replaced with D2 [Me2SiO2/2] were found, for example, T36D22, suggesting that general silicone resins consist of similar structures as silsesquioxanes. The Mark-Houwink exponent for these methyl resins was ~0.3, indicating the molecular shape to be compact. Investigation on the formation chemistry of the cubic octamers indicates that siloxane bond rearrangement is an important mechanism in the molecule build-up process.
AIM: To investigate morphological changes of intestinal smooth muscle contractile fibres in small bowel atresia patients. METHODS: Resected small bowel specimens from small bowel atresia patients (n = 12) were divided into three sections (proximal, atretic and distal). Standard histology hematoxylin-eosin staining and enzyme immunohistochemistry was performed to visualize smooth muscle contractile markers α-smooth muscle actin (SMA) and desmin using conventional paraffin sections of the proximal and distal bowel. Small bowel from age-matched patients (n = 2) undergoing Meckel's diverticulum resection served as controls.
RESULTS: The smooth muscle coat in the proximal bowel of small bowel atresia patients was thickened compared with control tissue, but the distal bowel was unchanged. Expression of smooth muscle contractile fibres SMA and desmin within the proximal bowel was slightly reduced compared with the distal bowel and control tissue. There were no major differences in the architecture of the smooth muscle within the proximal bowel and the distal bowel. The proximal and distal bowel in small bowel atresia patients revealed only minimal differences regarding smooth muscle morphology and the presence of smooth muscle contractile filament markers.
CONCLUSION: Changes in smooth muscle contractile filaments do not appear to play a major role in postoperative motility disorders in small bowel atresia.