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This publication is the result of a baseline study of the state of the higher education systems in the five Portuguese speaking countries in Africa (PALOP): Angola, Cape Verde, Guinea-Bissau, Mozambique and Sao Tome and Principe. The project was undertaken by an African international expert in the field of higher education studies and was fully sponsored and supported by the Association for the Development of Education in Africa (ADEA). The report offers a historical overview of the development of higher education in PALOP from colonial times to the present. The main objective of this baseline study is to map the landscape and dynamics of change in the higher education systems of PALOP countries. It focuses on describing the latest developments of trends of expansion, financing, governance and policy reforms closely linked to the development of higher education systems in these countries. Furthermore, the study will facilitate an informed debate and the dissemination of knowledge on the role of higher education for development in Africa.
Background: In cystic fibrosis, highly variable glucose tolerance is suspected. However, no study provided within-patient coefficients of variation. The main objective of this short report was to evaluate within-patient variability of oral glucose tolerance.
Methods: In total, 4,643 standardized oral glucose tolerance tests of 1,128 cystic fibrosis patients (median age at first test: 15.5 [11.5; 21.5] years, 48.8% females) were studied. Patients included were clinically stable, non-pregnant, and had at least two oral glucose tolerance tests, with no prior lung transplantation or systemic steroid therapy. Transition frequency from any one test to the subsequent test was analyzed and within-patient coefficients of variation were calculated for fasting and two hour blood glucose values. All statistical analysis was implemented with SAS 9.4.
Results: A diabetic glucose tolerance was confirmed in 41.2% by the subsequent test. A regression to normal glucose tolerance at the subsequent test was observed in 21.7% and to impaired fasting glucose, impaired glucose tolerance or both in 15.2%, 12.0% or 9.9%. The average within-patient coefficient of variation for fasting blood glucose was 11.1% and for two hour blood glucose 25.3%.
Conclusion: In the cystic fibrosis patients studied, a highly variable glucose tolerance was observed. Compared to the general population, variability of two hour blood glucose was 1.5 to 1.8-fold higher.
In this paper we argue that very high marginal labor income tax rates are an effective tool for social insurance even when households have preferences with high labor supply elasticity, make dynamic savings decisions, and policies have general equilibrium effects. To make this point we construct a large scale Overlapping Generations Model with uninsurable labor productivity risk, show that it has a wealth distribution that matches the data well, and then use it to characterize fiscal policies that achieve a desired degree of redistribution in society. We find that marginal tax rates on the top 1% of the earnings distribution of close to 90% are optimal. We document that this result is robust to plausible variation in the labor supply elasticity and holds regardless of whether social welfare is measured at the steady state only or includes transitional generations.
Species distributed across vast continental areas and across major biomes provide unique model systems for studies of biotic diversification, yet also constitute daunting financial, logistic and political challenges for data collection across such regions. The tree frog Dendropsophus minutus (Anura: Hylidae) is a nominal species, continentally distributed in South America, that may represent a complex of multiple species, each with a more limited distribution. To understand the spatial pattern of molecular diversity throughout the range of this species complex, we obtained DNA sequence data from two mitochondrial genes, cytochrome oxidase I (COI) and the 16S rhibosomal gene (16S) for 407 samples of D. minutus and closely related species distributed across eleven countries, effectively comprising the entire range of the group. We performed phylogenetic and spatially explicit phylogeographic analyses to assess the genetic structure of lineages and infer ancestral areas. We found 43 statistically supported, deep mitochondrial lineages, several of which may represent currently unrecognized distinct species. One major clade, containing 25 divergent lineages, includes samples from the type locality of D. minutus. We defined that clade as the D. minutus complex. The remaining lineages together with the D. minutus complex constitute the D. minutus species group. Historical analyses support an Amazonian origin for the D. minutus species group with a subsequent dispersal to eastern Brazil where the D. minutus complex originated. According to our dataset, a total of eight mtDNA lineages have ranges >100,000 km2. One of them occupies an area of almost one million km2 encompassing multiple biomes. Our results, at a spatial scale and resolution unprecedented for a Neotropical vertebrate, confirm that widespread amphibian species occur in lowland South America, yet at the same time a large proportion of cryptic diversity still remains to be discovered.
High lipoprotein expression and potent activation of host Toll-like receptor-2 (TLR2) are characteristic features of the staphylococcal species. Expression of TLR2 in the host is important for clearance of Staphylococcus aureus infection and host survival. Thus, we hypothesized that bacterial regulation of its intrinsic TLR2-stimulatory capacity could represent a means for immune evasion or host adaptation. We, therefore, compared clinical S. aureus isolates in regards to their TLR2 activation potential and assessed the bacterial factors that modulate TLR2-mediated recognition. S. aureus isolates displayed considerable variability in TLR2-activity with low to absent TLR2-activity in 64% of the isolates tested (68/106). Notably, strain-specific TLR2-activity was independent of the strain origin, e.g. no differences were found between strains isolated from respiratory specimen from cystic fibrosis patients or those isolated from invasive disease specimen. TLR2-activity correlated with protein A expression but not with the agr status. Capsule expression and small colony variant formation had a negative impact on TLR2-activity but any disruption of cell wall integrity enhanced TLR2 activation. Altogether, heterogeneity in host TLR2-activity reflects differences in metabolic activity and cell wall synthesis and/or remodeling.
Background: Targeted therapies have improved therapeutic options of treating renal cell carcinoma (RCC). However, drug response is temporary due to resistance development.
Methods: Functional and molecular changes in RCC Caki-1 cells, after acquired resistance to the mammalian target of rapamycin (mTOR)-inhibitor everolimus (Cakires), were investigated with and without additional application of the histone deacetylase (HDAC)-inhibitor valproic acid (VPA). Cell growth was evaluated by MTT assay, cell cycle progression and apoptosis by flow cytometry. Target molecules of everolimus and VPA, apoptotic and cell cycle regulating proteins were investigated by western blotting. siRNA blockade was performed to evaluate the functional relevance of the proteins.
Results: Everolimus resistance was accompanied by significant increases in the percentage of G2/M-phase cells and in the IC50. Akt and p70S6K, targets of everolimus, were activated in Cakires compared to drug sensitive cells. The most prominent change in Cakires cells was an increase in the cell cycle activating proteins cdk2 and cyclin A. Knock-down of cdk2 and cyclin A caused significant growth inhibition in the Cakires cells. The HDAC-inhibitor, VPA, counteracted everolimus resistance in Cakires, evidenced by a significant decrease in tumor growth and cdk2/cyclin A.
Conclusion: It is concluded that non-response to everolimus is characterized by increased cdk2/cyclin A, driving RCC cells into the G2/M-phase. VPA hinders everolimus non-response by diminishing cdk2/cyclin A. Therefore, treatment with HDAC-inhibitors might be an option for patients with advanced renal cell carcinoma and acquired everolimus resistance.
Halting biological invasions in Europe : from data to decisions ; a message from NEOBIOTA 2012
(2014)
The NEOBIOTA conferences initiated by the European Group on Biological Invasions represents a forum for exchange of ideas and discussion of topics related to biological invasions as well as an interface between science, application and policies (Kowarik and Starfinger 2009). The 7th NEOBIOTA conference (http://neobiota2012.blogspot.com.es/), held in Pontevedra (Spain) from 12–14 September 2012, brought together 288 participants (ecologists, conservationists, representatives of governmental agencies and stake-holders), from 24 European countries and 9 non-European ones (namely, Australia, Brazil, Canada, Chile, Colombia, New Zealand, South Africa, United States and Venezuela).
Halophilic archaea cultivated from surface sterilized middle-late Eocene rock salt are polyploid
(2014)
Live bacteria and archaea have been isolated from several rock salt deposits of up to hundreds of millions of years of age from all around the world. A key factor affecting their longevity is the ability to keep their genomic DNA intact, for which efficient repair mechanisms are needed. Polyploid microbes are known to have an increased resistance towards mutations and DNA damage, and it has been suggested that microbes from deeply buried rock salt would carry several copies of their genomes. Here, cultivable halophilic microbes were isolated from a surface sterilized middle-late Eocene (38–41 million years ago) rock salt sample, drilled from the depth of 800 m at Yunying salt mine, China. Eight unique isolates were obtained, which represented two haloarchaeal genera, Halobacterium and Halolamina. We used real-time PCR to show that our isolates are polyploid, with genome copy numbers of 11–14 genomes per cell in exponential growth phase. The ploidy level was slightly downregulated in stationary growth phase, but the cells still had an average genome copy number of 6–8. The polyploidy of halophilic archaea living in ancient rock salt might be a factor explaining how these organisms are able to overcome the challenge of prolonged survival during their entombment.
It was long assumed that translation initiation in prokaryotes generally occurs via the so-called Shine Dalgarno (SD) mechanism. Recently, it became clear that translation initiation in prokaryotes is more heterogeneous. In the haloarchaeon Haloferax volcanii, the majority of transcripts is leaderless and most transcripts with a 5′-UTR lack a SD motif. Nevertheless, a bioinformatic analysis predicted that 20–30% of all genes are preceded by a SD motif in haloarchaea. To analyze the importance of the SD mechanism for translation initiation in haloarchaea experimentally the monocistronic sod gene was chosen, which contains a 5′-UTR with an extensive SD motif of seven nucleotides and a length of 19 nt, the average length of 5′UTRs in this organism. A translational fusion of part of the sod gene with the dhfr reporter gene was constructed. A mutant series was generated that matched the SD motif from zero to eight positions, respectively. Surprisingly, there was no correlation between the base pairing ability between transcripts and 16S rRNA and translational efficiency in vivo under several different growth conditions. Furthermore, complete replacement of the SD motif by three unrelated sequences did not reduce translational efficiency. The results indicate that H. volcanii does not make use of the SD mechanism for translation initiation in 5′-UTRs. A genome analysis revealed that while the number of SD motifs in 5′-UTRs is rare, their fraction within open reading frames is high. Possible biological functions for intragenic SD motifs are discussed, including re-initiation of translation at distal genes in operons.
The simultaneous description of the hadronic yields, pion, kaon and proton spectra, elliptic flows and femtoscopy scales in hydrokinetic model of A+A collisions is presented at different centralities for the top RHIC and LHC energies. The hydrokinetic model is used in its hybrid version that allows one to switch correctly to the UrQMD cascade at the isochronic hypersurface which separates the cascade stage and decaying hydrodynamic one. The results are compared with pure hybrid model where hydrodynamics and hadronic cascade are matching just at the non-space-like hypersurface of chemical freeze-out. The initial conditions are based on both Glauber- and KLN- Monte-Carlo simulations and results are compared. It seems that the observables, especially femtoscopy data, prefer the Glauber initial conditions. The modification of the particle number ratios caused, in particular, by the particle annihilations at the afterburn stage is analyzed.
In many markets, design is one of the key factors in determining a product’s success. The present research offers insights into the role of design for the success of cars, and offers procedures to measure the quality of the designs objectively. The authors show that visual design plays a major role in a product’s success in the automobile market. In the study, two visual design aspects were already sufficient to significantly improve traditional sales forecasting models for cars. Visual prototypicality and visual complexity both had a positive impact on sales, and designs that were perceived as both prototypical and complex were the ones that displayed the best results. Most design evaluation used to be based on subjective measures, but the researcher applied a new, objective procedure to measure prototypicality and complexity. While the latter was detected by the disk space needed by the compressed image file, the new approach for measuring prototypicality was even more sophisticated. It relied on the technique of image morphing. Morphing is a technique that allows the construction of a visual synthesis – or average picture – from a number of individual pictures. Once a car morph is developed, one can determine the visual similarity of different car models to the morph in order to obtain its prototypicality. In principle, this procedure can be automated completely, and including a large number of versions is possible. These measures therefore seem suitable for supporting design decision processes in practice.
In Growing up with Tanzania. Karim Hirji, a renowned Professor of Medical Statistics and Fellow of the Tanzania Academy of Science, presents a multi-faceted, evocative portrait of his joyous but conflicted passage to adulthood during colonial and early-Uhuru Tanzania. His smooth style engages the reader with absorbing true tales, cultural currents, critical commentary and progressive possibilities. By vibrantly contrasting the hope-filled sixties with the cynical modern era, he also lays bare the paradoxes of personal life and society, past and present.
We study the dispersion of debt maturities across time, which we call "granularity of corporate debt,'' using a model in which a firm's inability to roll over expiring debt causes inefficiencies, such as costly asset sales or underinvestment. Since multiple small asset sales are less costly than a single large one, firms diversify debt rollovers across maturity dates. We construct granularity measures using data on corporate bond issuers for the 1991-2012 period and establish a number of novel findings. First, there is substantial variation in granularity in that we observe both very concentrated and highly dispersed maturity structures. Second, observed variation in granularity supports the model's predictions, i.e. maturities are more dispersed for larger and more mature firms, for firms with better investment oppo
God was African
(2014)
When Kendem, a varsity instructor, returns to his native Lewoh countryside where he spent his childhood, he is seeking relief from the complexity of human civilization after attending the Fulbright Institute in the United States. Instead, he is confronted with two seething issues: how to reveal to his sick and troubled mother the situation in which he finds his elder brother, the successor of Mbe Tanju-Ngong's household, who travelled to the United States many years before and had never returned and the dispute over Fuo Beyano's funeral which is tearing the land apart, whether the deceased village chief, should be given a Christian burial or he should, according to the age-old tradition of Lewoh people, go through a ritual to enable him return and continue ruling his people.
Halobacillus halophilus, a moderately halophilic bacterium isolated from salt marshes, produces various compatible solutes to cope with osmotic stress. Glutamate and glutamine are dominant compatible solutes at mild salinities. Glutamine synthetase activity in cell suspensions of Halobacillus halophilus wild type was shown to be salt dependent and chloride modulated. A possible candidate to catalyze glutamine synthesis is glutamine synthetase A2, whose transcription is stimulated by chloride. To address the role of GlnA2 in the biosynthesis of the osmolytes glutamate and glutamine, a deletion mutant (ΔglnA2) was generated and characterized in detail. We compared the pool of compatible solutes and performed transcriptional analyses of the principal genes controlling the solute production in the wild type strain and the deletion mutant. These measurements did not confirm the hypothesized role of GlnA2 in the osmolyte production. Most likely the presence of another, yet to be identified enzyme has the main contribution in the measured activity in crude extracts and probably determines the total chloride-modulated profile. The role of GlnA2 remains to be elucidated.
The exposure to tobacco smoke during pregnancy is considered to be amongst the most harmful avoidable risk factors. In this scientometric and gender study scientific data on smoking and pregnancy was analyzed using a variety of objective scientometric methods like the number of scientific contributions, the number of citations and the modified h-index in combination with gender-specific investigations. Covering a time period from 1900 to 2012, publishing activities of 27,955 authors, institutions and countries, reception within the international scientific community and its reactions were analyzed and interpreted. Out of 10,043 publications the highest number of scientific works were published in the USA (35.5%), followed by the UK (9.9%) and Canada (5.3%). These nations also achieve the highest modified h-indices of 128, 79 and 62 and the highest citation rates of 41.4%, 8.6% and 5.3%, respectively. Out of 12,596 scientists 6,935 are female (55.1%), however they account for no more than 49.7% of publications (12,470) and 42.8% of citations (172,733). The highest percentage of female experts about smoking and pregnancy is found in Australasia (60.7%), while the lowest is found in Asia (41.9%). The findings of the study indicate an increase in gender equality as well as in quantity and quality of international scientific research about smoking and pregnancy in the future.
Treatment with inhibitors of the receptor tyrosine kinase FLT3 are currently studied as promising therapies in acute myeloid leukemia (AML). However, only a subset of patients benefit from these treatments and the presence of activating mutations within FLT3 can predict response to a certain extent only. ...
The long-run consumption risk (LRR) model is a promising approach to resolve prominent asset pricing puzzles. The simulated method of moments (SMM) provides a natural framework to estimate its deep parameters, but caveats concern model solubility and weak identification. We propose a two-step estimation strategy that combines GMM and SMM, and for which we elicit informative macroeconomic and financial moment matches from the LRR model structure. In particular, we exploit the persistent serial correlation of consumption and dividend growth and the equilibrium conditions for market return and risk-free rate, as well as the model-implied predictability of the risk-free rate. We match analytical moments when possible and simulated moments when necessary and determine the crucial factors required for both identification and reasonable estimation precision. A simulation study – the first in the context of long-run risk modeling – delineates the pitfalls associated with SMM estimation of a non-linear dynamic asset pricing model. Our study provides a blueprint for successful estimation of the LRR model.
Girl on the Edge: A Memoir
(2014)
Ruth was four years old when her father was arrested for high treason and her world was turned upside-down. She grew up in constant fear of Special Branch policemen knocking on the door to arrest her mother or father, prominent South African communist. Ruth learned how to keep her mouth shut, to look out for microphones in the walls and to beware of friends who could betray her trust. At fourteen, Ruth left South Africa, clutching her teddy bear in one hand and her drawings in the other. A plan to England carried her into exile, a new world where she struggled to reconstruct a life fractured by fear. With an artist's eye for detail and colour, Ruth recalls her life with unflinching honesty: the Treason Trial; her struggle to conform; Friern Barnet Asylum for the 'hopeless insane'; LSD, protests, and free love in London, art school and motherhood; communes and camping- all steps in a journey that finally brought her home to South Africa on the brink of change. Heart- wrenchingly sad one minute, bursting with life and vigour the next, seamed throughout by strength and courage, girl on the edge allows us to look deep into one woman's life and travel with her to the brink and back again.
Two new species and one subspecies of Pharnaciini, belonging to two different genera, are described from Vietnam: one species and subspecies of Phryganistria Stål, 1875 and one species of Phobaeticus Brunner von Wattenwyl, 1907. Two species currently attributed to the genus Ramulus Saussure, 1862, Ramulus magnus (Brunner von Wattenwyl, 1907) and R. chinensis (Brunner von Wattenwyl, 1907), are transferred to Baculonistria Hennemann & Conle, 2008 comb. nov. Phobaeticus longicornis Bi & Wang, 1998 and Phobaeticus yuexiensis Chen & He, 1993 represent the male and female of Baculonistria magnus (Brunner von Wattenwyl, 1907) syn. nov. A lectotype is designated for Baculonistria chinensis (Brunner von Wattenwyl, 1907). The genus Baculonistria now contains three species. Nearchus bachmaensis Ta & Hoang, 2004 is transferred to Phryganistria and the new combination Phryganistria bachmaensis (Ta & Hoang, 2004) comb. nov. is proposed. The species is redescribed and the authors’ attribution corrected, the egg is described and figured for the first time.
Phryganistria tamdaoensis sp. nov. is described and figured from both sexes and the egg. Females of P. tamdaoensis sp. nov. are easily recognised by the conspicuously enlarged lanceolate cerci, a character previously unknown in this tribe. The distribution range of Phryganistria heusii heusii (Hennemann & Conle, 1997) is extended to Tam Dao National Park. A new subspecies Phryganistria heusii yentuensis subsp. nov. is described from Tay Yen Tu Nature Reserve from adult males and females and the eggs. Males can easily be distinguished from the nominal subspecies by their colouration. This huge subspecies represents the second longest insect recorded to date. A key to the species of the genus Phryganistria is provided. Phobaeticus trui sp. nov. is described from central Vietnam. It is the first species of Phobaeticus recorded from Vietnam. Adults of both sexes are illustrated.
Freshwater ecosystems are increasingly impacted by alien invasive species which have the potential to alter various ecological interactions like predator-prey and host-parasite relationships. Here, we simultaneously examined predator-prey interactions and parasitization patterns of the highly invasive round goby (Neogobius melanostomus) in the rivers Rhine and Main in Germany. A total of 350 N. melanostomus were sampled between June and October 2011. Gut content analysis revealed a broad prey spectrum, partly reflecting temporal and local differences in prey availability. For the major food type (amphipods), species compositions were determined. Amphipod fauna consisted entirely of non-native species and was dominated by Dikerogammarus villosus in the Main and Echinogammarus trichiatus in the Rhine. However, the availability of amphipod species in the field did not reflect their relative abundance in gut contents of N. melanostomus. Only two metazoan parasites, the nematode Raphidascaris acus and the acanthocephalan Pomphorhynchus sp., were isolated from N. melanostomus in all months, whereas unionid glochidia were only detected in June and October in fish from the Main. To analyse infection pathways, we examined 17,356 amphipods and found Pomphorhynchus sp. larvae only in D. villosus in the river Rhine at a prevalence of 0.15%. Dikerogammarus villosus represented the most important amphipod prey for N. melanostomus in both rivers but parasite intensities differed between rivers, suggesting that final hosts (large predatory fishes) may influence host-parasite dynamics of N. melanostomus in its introduced range.
In this article, I review select institutional and analytical traditions of Legal History in 20th century Germany, in order to put forth some recommendations for the future development of our discipline. A careful examination of the evolution of Legal History in Germany in the last twenty-five years, in particular, reveals radical transformations in the research framework: Within the study of law, there has been a shift in the internal reference points for Legal History. While the discipline is opening up to new understandings of law and to its neighboring disciplines, its institutional position at the law departments has become precarious. Research funding is being allocated in new ways and the German academic system is witnessing ever more internal differentiation. Internationally, German contributions and analytic traditions are receiving less attention and are being marginalized as new regions enter into a global dialogue on law and its history. The German tradition of research in Legal History had for long been setting benchmarks internationally; now it has to reflect upon and react to new global knowledge systems that have emerged in light of the digital revolution and the transnationalization of legal and academic systems. If legal historians in Germany accept the challenge these changing conditions pose, thrilling new intellectual and also institutional opportunities emerge. Especially the transnationalization of law and the need for a transnational legal scholarship offers fascinating perspectives for Legal History.
This is the first English edition of Tamara Mcheidze's monograph on the spiders of Georgia (Mcheidze 1997; in alternative transliteration: Mkheidze 1997), containing taxonomic, faunistic and ecological information on 362 spider species recorded by T. Mcheidze in Georgia between the 1920s and 1992. The English edition resembles the original text, with a preface, taxonomic comments and a part with supplementary information on the locations, a location map and an index provided by the editor.
The ladybeetle Anovia sp. (Coleoptera: Coccinellidae: Noviini), known as an important natural enemy of the Colombian fluted scale, Crypticeria muticicatrices Kondo and Gullan (Hemiptera: Coccoidea: Monophlebidae) is here identified as A. punica Gordon, 1972, and reported for the first time from Peru. Here we provide information and illustrations of the great variation in color and dorsal patterns of A. punica found in Colombia and Peru.
Ultraviolet-B (UVB)-induced inflammation produces a dose-dependent mechanical and thermal hyperalgesia in both humans and rats, most likely via inflammatory mediators acting at the site of injury. Previous work has shown that the gene expression of cytokines and chemokines is positively correlated between species and that these factors can contribute to UVB-induced pain. In order to investigate other potential pain mediators in this model we used RNA-seq to perform genome-wide transcriptional profiling in both human and rat skin at the peak of hyperalgesia. In addition we have also measured transcriptional changes in the L4 and L5 DRG of the rat model. Our data show that UVB irradiation produces a large number of transcriptional changes in the skin: 2186 and 3888 genes are significantly dysregulated in human and rat skin, respectively. The most highly up-regulated genes in human skin feature those encoding cytokines (IL6 and IL24), chemokines (CCL3, CCL20, CXCL1, CXCL2, CXCL3 and CXCL5), the prostanoid synthesising enzyme COX-2 and members of the keratin gene family. Overall there was a strong positive and significant correlation in gene expression between the human and rat (R = 0.8022). In contrast to the skin, only 39 genes were significantly dysregulated in the rat L4 and L5 DRGs, the majority of which had small fold change values. Amongst the most up-regulated genes in DRG were REG3B, CCL2 and VGF. Overall, our data shows that numerous genes were up-regulated in UVB irradiated skin at the peak of hyperalgesia in both human and rats. Many of the top up-regulated genes were cytokines and chemokines, highlighting again their potential as pain mediators. However many other genes were also up-regulated and might play a role in UVB-induced hyperalgesia. In addition, the strong gene expression correlation between species re-emphasises the value of the UVB model as translational tool to study inflammatory pain.
Symbiotic nitrogen fixation (SNF) in root nodules of grain legumes such as chickpea is a highly complex process that drastically affects the gene expression patterns of both the prokaryotic as well as eukaryotic interacting cells. A successfully established symbiotic relationship requires mutual signaling mechanisms and a continuous adaptation of the metabolism of the involved cells to varying environmental conditions. Although some of these processes are well understood today many of the molecular mechanisms underlying SNF, especially in chickpea, remain unclear. Here, we reannotated our previously published transcriptome data generated by deepSuperSAGE (Serial Analysis of Gene Expression) to the recently published draft genome of chickpea to assess the root- and nodule-specific transcriptomes of the eukaryotic host cells. The identified gene expression patterns comprise up to 71 significantly differentially expressed genes and the expression of twenty of these was validated by quantitative real-time PCR with the tissues from five independent biological replicates. Many of the differentially expressed transcripts were found to encode proteins implicated in sugar metabolism, antioxidant defense as well as biotic and abiotic stress responses of the host cells, and some of them were already known to contribute to SNF in other legumes. The differentially expressed genes identified in this study represent candidates that can be used for further characterization of the complex molecular mechanisms underlying SNF in chickpea.
Lichens are present in most land ecosystems, frequently occupying habitats where few other organisms are able to survive. Their contribution to the ecosystems in terms of biomass and ground cover increases with latitude and altitude, being, together with bryophytes, the most conspicuous component of alpine and polar landscapes. Whereas some polar lichens have reduced distributions and are restricted to high latitudes, most of them have very wide distributional ranges, which oven extend over several climatic regions. Many of them are common to Polar Regions of both hemispheres, a distributional pattern that has been denominated as bipolar, antitropical or amphitropical. Bipolar distributions are not exclusive to lichens, but common to many groups of organisms. The bipolar element in lichens is exceptional as it includes a large number of species, while in most other land organisms it includes genera or families but very seldom species.
In this dissertation I use the bipolar lichen Cetraria aculeata to give a first insight into the phylogeography of this biogeographic element in lichens. I discuss how and when the disjunct distribution of C. aculeata came to be, and try to partial out the roles that historical and ecological processes played in shaping its distribution.
Sampling was designed to cover a wide geographic extension. The main e"ort was made to collect in boreal, temperate and tropical mountain ranges in North and South America, as well to include Mediterranean populations in which specimens with deviant morphologies are observed.
I found that Cetraria aculeata forms a genetically congruent taxon. Although whether it should include C. muricata remains unsolved, I excluded all specimens identified as the latter from our analyses. Thee populations of both algal and fungal symbionts have a strong geographic structure. The study of the lichen fungus suggested that the species originated in the Eurasian continent and later expanded to acquire its current distribution during the Pleistocene. The results showed that all American populations originated from an ancestral population, more similar to the extant Arctic populations than to the Mediterranean ones.
The comparison between the structure of fungal and algal populations showed a high degree of coherence between them. However, the similarity in photobiont use between Arctic and Antarctic populations suggests that photobiont use responds not only to a history of codispersal in vegetative propagula, but it is also a result of a selective process related to climate. Since this climatic pattern of similarity is also found in the community of Alphaproteobacteria associated with C. aculeata, we concluded that lichens might be able to accommodate or to respond to different environmental conditions by selectively associating with different symbiotic partners.
Lastly, we found the Mediterranean populations of C. aculeata to be genetically differentiated in algal and fungal symbionts from the rest of the populations. While we found no grounds to believe that the overgrown morphs encountered in the region are due to the association with different algal lineages, I believe that a switch in photobiont use might be responsible for the pattern of genetic isolation encountered. Furthermore, I suggest that the Mediterranean and bipolar C. aculeata could be two different species, since both are ecologically, genetically and at least in part morphologically divergent.
The haloarchaeon Haloferax volcanii was shown to contain 145 intergenic and 45 antisense sRNAs. In a comprehensive approach to unravel various biological roles of haloarchaeal sRNAs in vivo, 27 sRNA genes were selected and deletion mutants were generated. The phenotypes of these mutants were compared to that of the parent strain under ten different conditions, i.e. growth on four different carbon sources, growth at three different salt concentrations, and application of four different stress conditions. In addition, cell morphologies in exponential and stationary phase were observed. Furthermore, swarming of 17 mutants was analyzed. 24 of the 27 mutants exhibited a difference from the parent strain under at least one condition, revealing that haloarchaeal sRNAs are involved in metabolic regulation, growth under extreme conditions, regulation of morphology and behavior, and stress adaptation. Notably, 7 deletion mutants showed a gain of function phenotype, which has not yet been described for any other prokaryotic sRNA gene deletion mutant. Comparison of the transcriptomes of one sRNA gene deletion mutant and the parent strain led to the identification of differentially expressed genes. Genes for flagellins and chemotaxis were up-regulated in the mutant, in accordance with its gain of function swarming phenotype. While the deletion mutant analysis underscored that haloarchaeal sRNAs are involved in many biological functions, the degree of conservation is extremely low. Only 3 of the 27 genes are conserved in more than 10 haloarchaeal species. 22 of the 27 genes are confined to H. volcanii, indicating a fast evolution of haloarchaeal sRNA genes.
Generating functionals may guide the evolution of a dynamical system and constitute a possible route for handling the complexity of neural networks as relevant for computational intelligence.We propose and explore a new objective function, which allows to obtain plasticity rules for the afferent synaptic weights. The adaption rules are Hebbian, self-limiting, and result from the minimization of the Fisher information with respect to the synaptic flux. We perform a series of simulations examining the behavior of the new learning rules in various circumstances.The vector of synaptic weights aligns with the principal direction of input activities, whenever one is present. A linear discrimination is performed when there are two or more principal directions; directions having bimodal firing-rate distributions, being characterized by a negative excess kurtosis, are preferred. We find robust performance and full homeostatic adaption of the synaptic weights results as a by-product of the synaptic flux minimization. This self-limiting behavior allows for stable online learning for arbitrary durations.The neuron acquires new information when the statistics of input activities is changed at a certain point of the simulation, showing however, a distinct resilience to unlearn previously acquired knowledge. Learning is fast when starting with randomly drawn synaptic weights and substantially slower when the synaptic weights are already fully adapted.
The Generalized Uncertainty Principle (GUP) arises from Quantum Gravity thought experiments and contains a minimal lenght. In this thesis I calculate Schwarzschild Black Holes that are modified by the GUP. These Black Holes have the property, that their temperature does not diverge for small masses, although they still posses a curvature singularity. I calculate analytically that in more than 3+1 dimensions the temperature diverges again.
Background: Alzheimer's disease is a common debilitating dementia with known heritability, for which 20 late onset susceptibility loci have been identified, but more remain to be discovered. This study sought to identify new susceptibility genes, using an alternative gene-wide analytical approach which tests for patterns of association within genes, in the powerful genome-wide association dataset of the International Genomics of Alzheimer's Project Consortium, comprising over 7 m genotypes from 25,580 Alzheimer's cases and 48,466 controls.
Principal findings: In addition to earlier reported genes, we detected genome-wide significant loci on chromosomes 8 (TP53INP1, p = 1.4×10−6) and 14 (IGHV1-67 p = 7.9×10−8) which indexed novel susceptibility loci.
Significance: The additional genes identified in this study, have an array of functions previously implicated in Alzheimer's disease, including aspects of energy metabolism, protein degradation and the immune system and add further weight to these pathways as potential therapeutic targets in Alzheimer's disease.
Smut fungi are well-suited to investigate the ecology and evolution of plant pathogens, as they are strictly biotrophic, yet cultivable on media. Here we report the genome sequence of Melanopsichium pennsylvanicum, closely related to Ustilago maydis and other Poaceae-infecting smuts, but parasitic to a dicot plant. To explore the evolutionary patterns resulting from host adaptation after this huge host jump, the genome of M. pennsylvanicum was sequenced and compared to the genomes of Ustilago maydis, Sporisorium reilianum, and Ustilago hordei. While all four genomes had a similar completeness in CEGMA analyses, gene absence was highest in M. pennsylvanicum, and most pronounced in putative secreted proteins, which are often considered as effector candidates. In contrast, the amount of private genes was similar among the species, highlighting that gene loss rather than gene gain is the hallmark of adaptation after the host jump to the dicot host. Our analyses revealed a trend of putative effectors to be next to another putative effector, but the majority of these are not in clusters and thus the focus on pathogenicity clusters might not be appropriate for all smut genomes. Positive selection studies revealed that M. pennsylvanicum has the highest number and proportion of genes under positive selection. In general, putative effectors showed a higher proportion of positively selected genes than non-effector candidates. The 248 putative secreted effectors found in all four smut genomes might constitute a core set needed for pathogenicity, while those 92 that are found in all grass-parasitic smuts, but have no ortholog in M. pennsylvanicum might constitute a set of effectors important for successful colonization of grass hosts.
Gender Issues in African Literature examines the ways in which some protagonists of African fictions are made to counter and challenge intertwined Western discourses on gender, employment, sexuality, and health. Here the conflict between Tradition and Modernity is argues from the favourite premise of male supremacist ideology showing how women have -unlearned- these false concepts to build a sustained feminist movement and (re)learn the value of sisterhood. There is a bold attempt to reread Achebe as a consistent in urging women to fight the seemingly oppressive structures that have traditionally discriminated against them, and to disregard their diversity and embrace their unity. A chapter of Feminist Re-writing disagrees with the attempt to equate theory with political activism and presents Feminist literature as more than a verbal assertion that points to Feminist aesthetics and politics. The use of the trauma theory and testimonio literature to explore traumatisation of female characters and its impact for Zimbabwean civil society is a useful addition to these gender studies in African literature.
One of the major issues this book examines is what the African experience and identity have contributed to the debate on citizenship in the era of globalisation. This volume presents case studies of different African contexts, illustrating the gendered aspects of citizenship as experienced by African men and women. Citizenship carries manifold gendered aspects and given the distinct gender roles and responsibilities, globalisation affects citizenship in different way. It further examines new forms of citizenship emerging from the current era dominated by a neoliberal focus. This book is not exclusive in terms of theorisation but its focus on African contexts, with an in-depth analysis taking into consideration local culture and practices and their implications for citizenship, provides a good foundation for further scholarly work on gender and citizenship in Africa.
Background: Since sorafenib has shown activity in different tumour types and gemcitabine regimens improved the outcome for biliary tract cancer (BTC) patients, we evaluated first-line gemcitabine plus sorafenib in a double-blind phase II study.
Patients and methods: 102 unresectable or metastatic BTC patients with histologically proven adenocarcinoma of gallbladder or intrahepatic bile ducts, Eastern Cooperative Oncology Group (ECOG) 0–2 were randomised to gemcitabine (1000 mg/m2 once weekly, first 7-weeks + 1-week rest followed by once 3-weeks + 1-week rest) plus sorafenib (400 mg twice daily) or placebo. Treatment continued until progression or unacceptable toxicity. Tumour samples were prospectively stained for sorafenib targets and potential biomarkers. Serum samples (first two cycles) were measured for vascular endothelial growth factors (VEGFs), vascular endothelial growth factor receptor 2 (VEGFR-2) and stromal cell-derived factor 1 (SDF1)α by enzyme-linked immunosorbent assay (ELISA).
Results: Gemcitabine plus sorafenib was generally well tolerated. Four and three patients achieved partial responses in the sorafenib and placebo groups, respectively. There was no difference in the primary end-point, median progression-free survival (PFS) for gemcitabine plus sorafenib versus gemcitabine plus placebo (3.0 versus 4.9 months, P = 0.859), and no difference for median overall survival (OS) (8.4 versus 11.2 months, P = 0.775). Patients with liver metastasis after resection of primary BTC survived longer with sorafenib (P = 0.019) compared to placebo. Patients who developed hand-foot syndrome (HFS) showed longer PFS and OS than patients without HFS. Two sorafenib targets, VEGFR-2 and c-kit, were not expressed in BTC samples. VEGFR-3 and Hif1α were associated with lymph node metastases and T stage. Absence of PDGFRβ expression correlated with longer PFS.
Conclusion: The addition of sorafenib to gemcitabine did not demonstrate improved efficacy in advanced BTC patients. Biomarker subgroup analysis suggested that some patients might benefit from combined treatment.
The neutron sensitivity of the C6D6 detector setup used at n_TOF facility for capture measurements has been studied by means of detailed GEANT4 simulations. A realistic software replica of the entire n_TOF experimental hall, including the neutron beam line, sample, detector supports and the walls of the experimental area has been implemented in the simulations. The simulations have been analyzed in the same manner as experimental data, in particular by applying the Pulse Height Weighting Technique. The simulations have been validated against a measurement of the neutron background performed with a natC sample, showing an excellent agreement above 1 keV. At lower energies, an additional component in the measured natC yield has been discovered, which prevents the use of natC data for neutron background estimates at neutron energies below a few hundred eV. The origin and time structure of the neutron background have been derived from the simulations. Examples of the neutron background for two different samples are demonstrating the important role of accurate simulations of the neutron background in capture cross-section measurements.