498 research outputs found
A convolute diversity of the Auriculariales (Agaricomycetes, Basidiomycota) with sphaeropedunculate basidia
Morphological and DNA data show that effused representatives of the Auriculariales (Basidiomycota) with sphaeropedunculate basidia belong to eleven genera of which seven are dealt with in this study. Among them, Myxarium is the largest genus containing 21 accepted species of which nine are reintroduced below and five are described as new. Protodontia is limited to three species only, P. subgelatinosa (the generic type) and two newly described species from Africa. Protoacia is a new monotypic genus for P. delicata, sp. nov., widely distributed on coniferous hosts in Eurasia. Myxariellum is erected for two new species with smooth hymenophore from northwestern North America while Gelacantha is introduced for G. pura, a new species with hydnoid hymenophore from Caucasus. Our data do not confirm the present synonymy of Sebacina sphaerospora with Tremella glaira, and these species are placed in two separate genera - Hydrophana, gen. nov., and Ofella, gen. nov., respectively. A key to European Myxarium and similar-looking species is included.Peer reviewe
Impact assessment of the European Clinical Trials Directive: a longitudinal, prospective, observational study analyzing patterns and trends in clinical drug trial applications submitted since 2001 to regulatory agencies in six EU countries
<p>Abstract</p> <p>Background</p> <p>Shifts in clinical trial application rates over time indicate if the attractiveness of a country or region for the conduct of clinical trials is growing or decreasing. The purpose of this observational study was to track changes in drug trial application patterns across several EU countries in order to analyze the medium-term impact of the EU Clinical Trials Directive 2001/20/EC on the conduct of drug trials.</p> <p>Methods</p> <p>Rates of Clinical Trial Applications (CTA) for studies with medicinal products in those six countries in the EU, which authorize on average more than 500 trials per year, were analyzed. Publicly available figures on the number of annually submitted CTA, the distribution of trials per phase and the type of sponsorship were tracked; missing data were provided by national drug agencies.</p> <p>Results</p> <p>Since 2001, the number of CTA in Italy and Spain increased significantly (5.0 and 2.5% average annual growth). For Italy, the gain was driven by a strong increase of applications from academic trial sponsors; Spain's growth was due to a rise in trials run by commercial sponsors. The Netherlands, Germany, France and the UK saw a decline (1.9, 2.3, 3.0 and 5.3% average annual diminution; significant (<it>P </it>< 0.05) except for Germany) in clinical drug trials. The decrease in the UK was caused by a sharp fall in academic trial activities. Across the six analyzed countries, no EU-wide trial-phase-specific patterns or trends were observed.</p> <p>Conclusions</p> <p>The EU Clinical Trials Directive 2001/20/EC did not achieve the harmonization of clinical trial requirements across Europe. Rather, it resulted in the leveling of clinical trial activities caused by a continuing decrease in CTA rates in the Netherlands, Germany, France and the UK. Southern European countries, Italy and Spain, benefited to some extent from policy changes introduced by the Directive. In Italy's case, national funding measures helped to considerably promote the conduct of non-commercial trials. On the other hand, the EU Directive-driven transition from liberal policy environments, based on non-explicit trial approval through notifications, towards red-taped processes of trial authorization, contributed to the decreases in trial numbers in Germany and the UK. In the latter case, national research governance concerns had a share in the country's marked decline. However, different EU member states successfully developed best practices, which a new European legislation should take into consideration to resume Europe's attractiveness and international competitiveness for the conduct of clinical trials.</p
The commonness of rarity: Global and future distribution of rarity across land plants
A key feature of lifeâs diversity is that some species are common but many more are rare. Nonetheless, at global scales, we do not know what fraction of biodiversity consists of rare species. Here, we present the largest compilation of global plant diversity to quantify the fraction of Earthâs plant biodiversity that are rare. A large fraction, ~36.5% of Earthâs ~435,000 plant species, are exceedingly rare. Sampling biases and prominent models, such as neutral theory and the k-niche model, cannot account for the observed prevalence of rarity. Our results indicate that (i) climatically more stable regions have harbored rare species and hence a large fraction of Earthâs plant species via reduced extinction risk but that (ii) climate change and human land use are now disproportionately impacting rare species. Estimates of global species abundance distributions have important implications for risk assessments and conservation planning in this era of rapid global change
Lichenological exploration of Algeria: historical overview and annotated bibliography, 1799-2013
yesDespite more than two centuries of almost uninterrupted surveys and studies of Algerian lichenology, the history and lichen diversity of Algeria are still poorly understood. During the preparation of a forthcoming checklist of Algerian lichens it was considered necessary to provide the present historical overview of lichenological exploration of the country from 1799 to 2013, supported by a reasonably comprehensive annotated bibliography of 171 titles
Biogeographical analyses to facilitate targeted conservation of orchid diversity hotspots in Costa Rica
Aim: We conduct a biogeographical assessment of orchids in a global biodiversity
hotspot to explore their distribution and occurrences of local hotspots while identifying geographic attributes underpinning diversity patterns. We evaluate habitat
characteristics associated with orchid diversity hotspots and make comparisons to
other centres of orchid diversity to test for global trends. The ultimate goal was to
identify an overall set of parameters that effectively characterize critical habitats to
target in local and global orchid conservation efforts.
Location: Costa Rica; Mesoamerica.
Taxon: Orchidaceae.
Methods: Data from an extensive set of herbarium records were used to map orchid
distributions and to identify diversity hotspots. Hotspot data were combined with
geographic attribute data, including environmental and geopolitical variables, and a
random forest regression model was utilized to assess the importance of each variable for explaining the distribution of orchid hotspots. A likelihood model was created based on variable importance to identify locations where suitable habitats and
unidentified orchid hotspots might occur.
Results: Orchids were widely distributed and hotspots occurred primarily in mountainous regions, but occasionally at lower elevations. Precipitation and vegetation
cover were the most important predictive variables associated with orchid hotspots.
Variable values underpinning Costa Rican orchid hotspots were similar to those reported at other sites worldwide. Models also identified suitable habitats for sustaining orchid diversity that occurred outside of known hotspots and protected areas.
Main conclusions: Several orchid diversity hotspots and potentially suitable habitats
occur outside of known distributions and/or protected areas. Recognition of these
sites and their associated geographic attributes provides clear targets for optimizing
orchid conservation efforts in Costa Rica, although certain caveats warrant consideration. Habitats linked with orchid hotspots in Costa Rica were similar to those documented elsewhere, suggesting the existence of a common biogeographical trend
regarding critical habitats for orchid conservation in disparate tropical regions.Universidad de Puerto Rico/[]/UPR/Puerto RicoUniversidad de Costa Rica/[]/UCR/Costa RicaUCR::VicerrectorĂa de InvestigaciĂłn::Unidades de InvestigaciĂłn::Ciencias Agroalimentarias::JardĂn BotĂĄnico Lankester (JBL
Lipid-Induced Peroxidation in the Intestine Is Involved in Glucose Homeostasis Imbalance in Mice
BACKGROUND: Daily variations in lipid concentrations in both gut lumen and blood are detected by specific sensors located in the gastrointestinal tract and in specialized central areas. Deregulation of the lipid sensors could be partly involved in the dysfunction of glucose homeostasis. The study aimed at comparing the effect of Medialipid (ML) overload on insulin secretion and sensitivity when administered either through the intestine or the carotid artery in mice. METHODOLOGY/PRINCIPAL FINDINGS: An indwelling intragastric or intracarotid catheter was installed in mice and ML or an isocaloric solution was infused over 24 hours. Glucose and insulin tolerance and vagus nerve activity were assessed. Some mice were treated daily for one week with the anti-lipid peroxidation agent aminoguanidine prior to the infusions and tests. The intestinal but not the intracarotid infusion of ML led to glucose and insulin intolerance when compared with controls. The intestinal ML overload induced lipid accumulation and increased lipid peroxidation as assessed by increased malondialdehyde production within both jejunum and duodenum. These effects were associated with the concomitant deregulation of vagus nerve. Administration of aminoguanidine protected against the effects of lipid overload and normalized glucose homeostasis and vagus nerve activity. CONCLUSIONS/SIGNIFICANCE: Lipid overload within the intestine led to deregulation of gastrointestinal lipid sensing that in turn impaired glucose homeostasis through changes in autonomic nervous system activity
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