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A list of all liverworts and mosses reported from the Maltese Islands with references has been compiled from the literature, which includes 23 species of liverworts and hornworts as well as 96 taxa of mosses. The list is completed by the results of a bryological fieldtrip in March 2008. During this trip, 14 species of liverworts and 40 species of mosses were collected, of which Cephaloziella baumgartneri, Didymodon luridus, Fissidens gracilifolius, Fossombronia echinata, Funaria pulchella, Riccia cavernosa and Weissia fallax are new to Malta. This raises the number of species known from the Maltese Islands to 23 horn- and liverworts and 100 mosses.
Cellular metabolism can be envisaged by fluorescence lifetime imaging of fluorophores sensitive to specific intracellular factors such as [H+], [Ca2+], [O2], membrane potential, temperature, polarity of the probe environment, and alterations in the conformation and interactions of macromolecules. Lifetime measurements of the probes allow the quantitative determination of the intracellular factors. Fluorescence microscopy taking advantage of time-correlated single photon counting is a novel method that outperforms all other techniques with its single photon sensitivity and picoseconds time resolution. In this work, a time- and space-correlated single photon counting system was established to investigate the behavior of 2-(4-(dimethylamino)styryl)-1-methylpyridinium iodide (DASPMI) in living cells. DASPMI is known to selectively stain mitochondria in living cells. The uptake and fluorescence intensity of DASPMI in mitochondria is a dynamic measure of membrane potential. Hence, an endeavour was made to elucidate the mechanism of DASPMI fluorescence by obtaining spectrally-resolved fluorescence decays in different solvents. A bi-exponential decay model was sufficient to globally describe the wavelength dependent fluorescence in ethanol and chloroform. While in glycerol, a three-exponential decay model was necessary for global analysis. In the polar low-viscous solvent water, a mono-exponential decay model fitted the decay data. The sensitivity of DASPMI fluorescence to solvent viscosity was analysed using various proportions of glycerol/ethanol mixtures. The lifetimes were found to increase with increasing solvent viscosity. The negative amplitudes of the short lifetime component found in chloroform and glycerol at the longer wavelengths validated the formation of new excited state species from the initially excited state. Time-resolved emission spectra in chloroform and glycerol showed a biphasic increase of spectral width and emission maxima. The spectral width had an initial fast increase within 150 ps and a near constant thereafter. A two-state model based on solvation of the initially excited state and further formation of TICT state has been proposed to explain the excited state kinetics and has been substantiated by the de-composition of time-resolved spectra. The knowledge of DASPMI photophysics in a variety of solvents now provides the means of deducing complex physiological parameters of mitochondria from its behavior in living cells. Spatially-resolved fluorescence decays from single mitochondria or only very few organelles of XTH2 cells signified distinctive three-exponential decay kinetics of viscous environment. Based on DASPMI photophysics in a variety of solvents, these lifetimes have been attributed to the fluorescence from locally excited state (LE), intramolecular charge transfer state (ICT) and twisted intramolecular charge transfer (TICT) state. A considerable variation in lifetime among mitochondria of different morphology and within single cell was evident corresponding to the high physiological variations within single cells. Considerable shortening of the short lifetime component (τ1) under high membrane potential condition, such as in the presence of ATP and/or substrate, was similar to quenching and dramatic decrease of lifetime in polar solvents. Under these conditions τ2 and τ3 increased with decreasing contribution. Upon treatment with ionophore nigericin, hyperpolarization of mitochondria resulted in remarkable shortening of τ1 from 159 ps to 38 ps. Inhibiting respiration by cyanide resulted in notable increase of mean lifetime and decrease of mitochondrial fluorescence. Increase of DASPMI fluorescence on conditions elevating mitochondrial membrane potential has been attributed to uptake according Nernst distributions, to de-localisation of π electrons, quenching processes of the methyl pyridinium moiety and restricted torsional dynamics at the mitochondrial inner membrane. Accordingly, determination of anisotropy in DASPMI stained mitochondria in living XTH2 cells, revealed dependence of anisotropy on membrane potential. Such changes in anisotropy attributed to restriction of the torsional dynamics about the flexible single bonds neighboring the olefinic double bond revealed the previously known sub-mitochondrial zones with higher membrane potential along its length. Membrane-potential-dependent changes in anisotropy have further been demonstrated in senescent chick embryo fibroblasts. In conclusion, spectroscopic observations of excited-state kinetics of DASPMI in solvents and its behavior in living cells had revealed for the first time its localisation, mechanism of voltage sensitive fluorescence and its membrane-potential-dependent anisotropy in living cells. The simultaneous dependence of DASPMI photophysics on mitochondrial inner membrane viscosity and transmembrane potential has been highlighted.
The bee fauna of the Greater Puerto Rico area was studied. A review of the previous relevant studies is presented. An annotated catalog and information about the origin and distributional patterns are also provided. Thirty-nine species of bees occur in Puerto Rico and adjacent islands. This fauna is composed of four elements: exclusive Puerto Rican endemics (26.5%); Antillean endemics occurring on multiple islands (76.5%); continental species that have also colonized the Antilles (23.5%); and species introduced through human activity (12.8%). The bee fauna was both low in its diversity and showed the highest level of disharmony in relation to other faunas of the Greater Antilles. A lectotype is here designated for Agapostemon krugii Wolcott, 1936.
The Barn
(2008)
As a veteran playwright and actor, Kwo Victor Elame Musinga is more than just a pioneer in popular theatre. His simple but profound messages demonstrate a depth of understanding and insight into human nature and the nature of society. The texts he crafts are universal and timeless in their content and appeal, even as the themes and situations that inspire them are localized in specific places, experiences and histories. The Barn is a collection of three topical plays. Njema captures the predicament of love in a context where innocence and trust are preyed upon by deceit, dishonesty, promiscuity, waywardness, callous indifference to human life, the reckless abandon of parental authority and wisdom by youth in a hurry to celebrate sexuality, irresponsible manhood with or without the connivance of girls/women, and HIV/AIDS and its terror. Invitation to God addresses elitism and fair-weather friendship even among believers. In Moka, the theme of friendship is explored through the simple act of dishonesty and greed, especially to those with whom one should be nothing but virtuous, open, generous and kind. In these plays Kwo Victor Elame Musinga explores the virtues of being human, while addressing the dark side of humanity.
Naturalness is one of the most important criteria in nature conservation. This paper examines the fundamental concepts underlying the definition and assessment of naturalness. Its role in nature conservation and forest management under conditions of global change is also discussed. The degree of naturalness may be defined in ordinal classes. The “static” concept of the potential natural vegetation (pnV), developed in the 1950ies, is mostly used as the reference state. In other cases, its reversed concept, the hemeroby (degree of articifiality) is assessed, based on the intensity and frequency of human impacts. Since the 1970ies, more attention has been given to natural dynamics than in earlier approaches, e.g. in forest succession models. At the end of the 1980ies, the previous importance was increasingly stressed of natural browsing by large herbivores and the role of predators. These large herbivors are extinct today in most cultural European landscapes. It is assumed, that they open up the canopy, and create park-like forest structures which contain a diversity of habitats for other types of organism (birds, insects). Changed and permanently changing environments and altering patterns of competition between species continue to modify natural processes today. Some of the more conspicuous effects are the extinction of native species and immigration of species to new regions. Long-lived ecosystems like forests are however not able to adapt quickly to such changes and may be unable to find a new balance with the environment. Today, such changes occur very rapidly, and are reducing the original naturalness of ecosystems. Because of this, the criterion “naturalness” must be downweighted. Conversely, more importance should be attached to other criteria: particularly originality (= original naturalness) and restorability. Forestry is contributing to this accelerated change of biocoenoses by increasing disturbances and introducing exotic tree species. Naturalisation of some exotic tree species modifies the natural processes and creates a “new allochthonous naturalness”. Because of this, forest planning should try to preserve or restore stands with attributes of the “original forest”. Exotic species should not be planted, or only in a very restricted way.
We perform a detailed study of the adjoint static potential in the pseudoparticle approach, which is a model for SU(2) Yang-Mills theory. We find agreement with the Casimir scaling hypothesis and there is clear evidence for string breaking. At the same time the potential in the fundamental representation is linear for large separations. Our results are in qualitative agreement with results from lattice computations.
' The United Nations-organised plebiscite on 11 February 1961 was one of the most significant events in the history of the southern and northern parts of the British-administered trust territory in Cameroon. John Percival was sent by the then Colonial Office as part of the team to oversee the process. This book captures the story of the plebiscite in all its dimensions and intricacies and celebrates the author's admiration for things African through a series of reminiscences of what life was like in the 1960s, both for the Africans themselves and for John Percival as a very young man. The complex story is also a series of reflections about the effect of the modern world on Africa. It is a thorough, insightful, rich and enlightening first-hand source on a political landmark that has never been told before in this way. In a vivid style with a great sense of humour, Percival's witty, cogent, eyewitness and active-participant account deconstructs the rumours and misrepresentations about the February 1961 Plebiscite which was a prelude to reunification and to the present day politics of 'belonging' in Cameroon. ''One of the major merits of this book is to provide us with a deeper insight into the role of those actors who have never been the subject of plebiscite studies, namely the Plebiscite Supervisory Officers.'' - Piet Konings, African Studies Centre, Leiden, The Netherlands John Percival-Anthropologist, Writer, Television Broadcaster of many innovative BBC series on the environment, history and anthropology. As a young graduate he was recruited and sent to serve in the Southern Cameroons as a Plesbiscite Supervisory Officer in 1961. He died in 2005 after a recent return visit to Cameroon with Nigel Wenban-Smith who writes an epilogue. This posthumous memoir has been edited by his wife, Lalage Neal.'
The correspondence between the terminology used for querying and the one used in content objects to be retrieved, is a crucial prerequisite for effective retrieval technology. However, as terminology is evolving over time, a growing gap opens up between older documents in (long-term) archives and the active language used for querying such archives. Thus, technologies for detecting and systematically handling terminology evolution are required to ensure "semantic" accessibility of (Web) archive content on the long run. As a starting point for dealing with terminology evolution this paper formalizes the problem and discusses issues, first ideas and relevant technologies.
Both, gas and particle scavenging contribute to the transport of organic compounds by ice crystals in the troposphere. To simulate these processes an experimental setup was developed to form airborne ice crystals under atmospheric conditions. Experiments were performed in a wall independent reactor (WIR) installed in a walk-in cold chamber maintained constantly at -20°C. Aerosol particles were added to the carrier gas of ambient air by an aerosol generator to allow heterogeneous ice formation. Temperature variations and hydrodynamic conditions of the WIR were investigated to determine the conditions for ice crystal formation and crystal growth by vapour deposition. In detail, the dependence of temperature variations from flow rate and temperature of the physical wall as well as temperature variations with an increasing reactor depth were studied. The conditions to provide a stable aerosol concentration in the carrier gas flow were also studied. The temperature distribution inside the reactor was strongly dependent on flow rate and physical wall temperature. At an inlet temperature of -20°C, a flow rate of 30 L•min exp -1 and a physical wall temperature of +5°C turned out to provide ideal conditions for ice formation. At these conditions a sharp and stable laminar down draft "jet stream" of cold air in the centre of the reactor was produced. Temperatures measured at the chamber outlet were kept well below the freezing point in the whole reactor depth of 1.0 m. Thus, melting did not affect ice formation and crystal growth. The maximum residence time for airborne ice crystals was calculated to at 40 s. Ice crystal growth rates increased also with increasing reactor depth. The maximum ice crystal growth rate was calculated at 2.82 mg• exp -1. Further, the removal efficiency of the cleaning device for aerosol particles was 99.8% after 10 min. A reliable particle supply was attained after a preliminary lead time of 15 min. Thus, the minimum lead time was determined at 25 min. Several test runs revealed that the WIR is suitable to perform experiments with airborne ice crystals.
The Tetragonoderus (Peronoscelis) quadriguttatus assemblage is a postulated monophyletic part of the intersectus complex. This assemblage is characterized against a background that includes review of a classification of the genus and comparison, in the form of a key, to other unrelated Western Hemisphere genera that share elongate tibial spurs with Tetragonoderus Dejean. The principal, easily observed feature that unites the three members (T. laevigatus Chaudoir, 1876; T. deuvei, new species (type locality: Cuijaba, Mato Grosso, Brazil), and T. quadriguttatus Dejean) of the quadriguttatus assemblage is the four-spotted elytra (two spots per elytron). These species are treated in detail, including key, synonymy (as required), comparisons, description (external and male genitalic features), habitat (if known), locality data, and geographical range map. Also, T. subfasciatus Putzeys, 1846, the elytral color pattern of whose members may be confused with the spotted pattern of the quadriguttatus assemblage, is treated similarly. The following new synonymies were established: T. quadriguttatus Dejean 1829 = T. columbicus Steinheil 1875 = T. lacordairei Chaudoir 1876 = T. tetragrammus Chaudoir 1876; and T. laevigatus Chaudoir 1876 = T. chaudoiri Liebke 1928 (replacement name for the junior homonym, T. unicolor Chaudoir, 1876). Lectotypes are designated for T. unicolor Chaudoir, T. lacordairei Chaudoir, and T. subfasciatus Putzeys. A neotype is designated for T. quadriguttatus Dejean. New distribution records in the West Indies for T. quadriguttatus are recorded for the islands of Grand Cayman, Jamaica and Hispaniola. These records may be the result of recent natural overseas dispersal from northern South America, or they may be the result of human-mediated accidental introduction, or a combination of both. The southern Floridian (Nearctic) records for T. laevigatus probably represent a recent accidental introduction through commerce, followed by dispersal through flights of adults.
This dissertation analyzes tax policy, corporations, and capital market effects. First, the Savings Directive, which has left a loophole by providing grandfathering for some securities, is examined. It can be shown that investors are not willing to pay a premium for bonds that are exempt from the withholding rate, so it may be concluded that the supply of existing loopholes is large enough to allow tax evaders to continue evasion at no additional cost. Second, tax neutrality towards alternative financing instruments for corporate investment is a ubiquitous demand in the political debate. However, the magnitude of possible efficiency costs of a departure from tax neutrality is hardly discussed. Against this background, this dissertation discusses the theory of capital structure and provides back-ofthe-envelope calculations of the possible efficiency cost of a tax distortion of the debt-equity decision. Third, the ex-dividend-day effect in relation to the Gennan tax reform of 2000/2001 is discussed. The abolishment of the imputation system allows reinvestigating the size of the exdividend- day effect. I find no structural break in the size of the German ex-dividend-day effect and no evidence of an ex-dividend-day price drop that exceeds the dividend paid. Fourth, an account of the quantitative development of tax legislation in post-war Germany is presented. It can be shown that the legislative output did not increase over the decades and is not affected by a split majority in the upper and lower houses. Finally, it turns out that an increasing fraction of this legislation is passed in December.
The influence of visual tasks on short and long-term memory for visual features was investigated using a change-detection paradigm. Subjects completed 2 tasks: (a) describing objects in natural images, reporting a specific property of each object when a crosshair appeared above it, and (b) viewing a modified version of each scene, and detecting which of the previously described objects had changed. When tested over short delays (seconds), no task effects were found. Over longer delays (minutes) we found the describing task influenced what types of changes were detected in a variety of explicit and incidental memory experiments. Furthermore, we found surprisingly high performance in the incidental memory experiment, suggesting that simple tasks are sufficient to instill long-lasting visual memories. Keywords: visual working memory, natural scenes, natural tasks, change detection
Background Cyclin B1, the regulatory subunit of cyclin-dependent kinase 1 (Cdk1), is essential for the transition from G2 phase to mitosis. Cyclin B1 is very often found to be overexpressed in primary breast and cervical cancer cells as well as in cancer cell lines. Its expression is correlated with the malignancy of gynecological cancers. Methods In order to explore cyclin B1 as a potential target for gynecological cancer therapy, we studied the effect of small interfering RNA (siRNA) on different gynecological cancer cell lines by monitoring their proliferation rate, cell cycle profile, protein expression and activity, apoptosis induction and colony formation. Tumor formation in vivo was examined using mouse xenograft models. Results Downregulation of cyclin B1 inhibited proliferation of several breast and cervical cancer cell lines including MCF-7, BT-474, SK-BR-3, MDA-MB-231 and HeLa. After combining cyclin B1 siRNA with taxol, we observed an increased apoptotic rate accompanied by an enhanced antiproliferative effect in breast cancer cells. Furthermore, control HeLa cells were progressively growing, whereas the tumor growth of HeLa cells pre-treated with cyclin B1 siRNA was strongly inhibited in nude mice, indicating that cyclin B1 is indispensable for tumor growth in vivo. Conclusion Our data support the notion of cyclin B1 being essential for survival and proliferation of gynecological cancer cells. Concordantly, knockdown of cyclin B1 inhibits proliferation in vitro as well as in vivo. Moreover, targeting cyclin B1 sensitizes breast cancer cells to taxol, suggesting that specific cyclin B1 targeting is an attractive strategy for the combination with conventionally used agents in gynecological cancer therapy.
Target2-Securities (T2S) is a project of the Eurosystem (central banking system of the Euro area) aiming to create a common platform to settle securities transactions in central bank money. This platform is another step of the European Union towards harmonization of capital markets and enhancement of competitive conditions in the Euro area. T2S is planned to go live in 2013 and to operate on a full costrecovery and non-profit base.
Tale of an African Woman
(2008)
The village of Yakiri has been cursed by ancestral wrath because of the treatment of Yaa, the first girl who wrestled her male goatherd peers to earn the right to be initiated into the society of manhood. Her struggle is taken up generations later by Yaya, the granddaughter of Tafan and Wirba. Orphaned like her forebear, Yaya becomes a star student in the village's primary school and promises to go far. But, ask the villagers, is it right to invest in an education for an African girl who may become the property of another village? An educated woman will abandon the farm where she is needed, wear high heels and try to order men around! In the midst of it all, one Irish missionary, living in Africa and for the most time with Africans, literally wiggles his way into hearts and minds. With his intervention, Yaya leaves the village to school in the city, but her troubles as a woman have not really begun. Yarns of cultural borrowing, indigestion and transcendence reveal the simple and complex ways in which community matters are confronted and decided. This happens in shrines where seers are consulted and cowry shells thrown, in palm wine houses, but also around the school and presbytery. The untold stories and perspectives of girls and women burst through in illuminating and uplifting ways. Quarrels, squabbles, near collisions and mutual conversions give way to innovative traditions.
The Oryctini (Coleoptera: Scarabaeidae: Dynastinae) is a large tribe of worldwide distribution with approximately 26 genera and 230 species. Fourteen genera and 113 species are found in the Neotropical region. Knowledge of the tribe in the Neotropics is fragmentary, necessitating further studies that address taxonomy, biology, and geographical distribution patterns. This study surveyed the Oryctini of the Brazilian Amazon. The composition of the group in the study area consisted of 7 genera, 18 species and 2 subspecies found in 7 states, 91 municipal districts, and approximately 167 specific localities. States with larger number of species are Amazonas and Pará, with 17 and 13 species respectively. Heterogomphus eteocles Burmeister, Heterogomphus aidoneus (Perty), Heterogomphus telamon Burmeister, Megaceras crassum Prell, and Megaceras laevipenne Prell are reported for the first time from the study area. Megaceras laevipenne is reported for the first time from Brazil. The taxonomy, descriptions, distribution maps, and biological and ecological data are provided for all species. A character analysis is provided as well as an identification key for all oryctine species that occur in the Brazilian Amazon.
The syndicated loan market, as a hybrid between public and private debt markets, comprises financial institutions with access to valuable private information about borrowers as a result of close bank-borrower relationships. In this paper, we seek empirical evidence for the costs of these relationships in a sample of UK syndicated loan contracts for the time period 1996 through 2005. Using detailed financial data for both borrowers (private and public companies) and for financial institutions, we find that undercapitalized banks charge higher loan spreads for loans to opaque borrowers using various measures for borrower opaqueness and controlling for bank, borrower and loan characteristics. We further analyze this hold-up effect over the business cycle and find that it only prevails during recessions. In expansion phases, however, we do not find evidence for banks exploiting their information monopoly. This finding is consistent with theories on bank reputation in bank loan commitments. Ambiguity about borrower financial health, which induces the information monopoly in the first place, also gives banks the discretion to exploit or not exploit informational captured borrowers. Our findings are both statistically and economically significant and robust to alternative bank and macroeconomic risk proxies. We address potential concerns about unobserved borrower heterogeneity exploiting the panel data nature of our sample. Using firm-bank fixed effect regressions, we find supporting evidence for our theoretical framework. JEL Classifications: G14, G21, G22, G23, G24 Keywords: Syndicated loans; Hold-up; Lending relationships; Business cycle
Background Drought is the major constraint to increase yield in chickpea (Cicer arietinum). Improving drought tolerance is therefore of outmost importance for breeding. However, the complexity of the trait allowed only marginal progress. A solution to the current stagnation is expected from innovative molecular tools such as transcriptome analyses providing insight into stress-related gene activity, which combined with molecular markers and expression (e)QTL mapping, may accelerate knowledge-based breeding. SuperSAGE, an improved version of the serial analysis of gene expression (SAGE) technique, generating genome-wide, high-quality transcription profiles from any eukaryote, has been employed in the present study. The method produces 26 bp long fragments (26 bp tags) from defined positions in cDNAs, providing sufficient sequence information to unambiguously characterize the mRNAs. Further, SuperSAGE tags may be immediately used to produce microarrays and probes for real-time-PCR, thereby overcoming the lack of genomic tools in non-model organisms. Results We applied SuperSAGE to the analysis of gene expression in chickpea roots in response to drought. To this end, we sequenced 80,238 26 bp tags representing 17,493 unique transcripts (UniTags) from drought-stressed and non-stressed control roots. A total of 7,532 (43%) UniTags were more than 2.7-fold differentially expressed, and 880 (5.0%) were regulated more than 8-fold upon stress. Their large size enabled the unambiguous annotation of 3,858 (22%) UniTags to genes or proteins in public data bases and thus to stress-response processes. We designed a microarray carrying 3,000 of these 26 bp tags. The chip data confirmed 79% of the tag-based results, whereas RT-PCR confirmed the SuperSAGE data in all cases. Conclusion This study represents the most comprehensive analysis of the drought-response transcriptome of chickpea available to date. It demonstrates that – inter alias – signal transduction, transcription regulation, osmolyte accumulation, and ROS scavenging undergo strong transcriptional remodelling in chickpea roots already 6 h after drought stress. Certain transcript isoforms characterizing these processes are potential targets for breeding for drought tolerance. We demonstrate that these can be easily accessed by micro-arrays and RT-PCR assays readily produced downstream of SuperSAGE. Our study proves that SuperSAGE owns potential for molecular breeding also in non-model crops.