71 research outputs found
Do ingredient and nutrient intake reveal individual dietary specialization in an omnivorous carnivore, the brown bear?
Generalist populations often harbor individual dietary specialists. Whether using a narrower set of resources than the population (= specialization) affects specialists' nutrient intake remains underexplored. We evaluated variation in ingredient and nutrient specialization in a European brown bear Ursus arctos population via the Proportional Similarity Index (PSi, from 0â=âhighly specialized to 1â=ânot specialized) and assessed associations of specialization with year, season and reproductive class. Different methodologies concerning the organization of raw data for PSi calculations were evaluated (i.e. the resolution of diet compositional data (feces vs the average of all feces per individual) and temporal restrictions for the population (yearâround vs withinâseason). Overall, a tendency for ingredient specialization (PSi 0.37 ± 0.14) and absence of nutrient specialization (PSi 0.79 ± 0.10) was observed. Ingredient specialization was mainly influenced by the proportion of berries, graminoids, oats and moose in the diet. Annual, seasonal and reproductive class effects were moderate and did not strongly affect PSi for both ingredients and nutrients. Organizing diet compositional data from a âfeces resolution' to âindividual resolution' decreased specialization. Changing the comparative population in PSi calculations from âallâyearâround' to âwithin year and season' also resulted in less pronounced specialization. The degree of specialization was not caused by individuals exhibiting consistent ingredient preferences over the years (low repeatability of PSi) except in spring. Our results suggested absence of nutrient specialization and mild ingredient specialization, which appeared to be an outcome of the ecological circumstances rather than specific individual traits. Additionally, we demonstrated that the methods applied can have substantial influence for the calculation of specialization indices
Scientific assessment of risk to populations of pythons listed by CITES as a result of trade
This report provides a scientific risk assessment of the effects that international trade in selected species of pythons (Pythonidae spp.) and python products may have on populations of these species. The assessment is based on the criteria given under the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). The risk assessment is limited to species in the genera Apodora, Aspidites, Liasis, Malayopython, Morelia, and Python imported/exported to/from Norway since 2010 (ToR §3). Risk assessments to determine species-specific detriment (cf. Res. Conf. 16.7 (Rev. CoP17) Non-detriment findings) were made for 17 species using a standardized approach. Significant data gaps affected the degree of uncertaintyassociated with the assessments. Data gaps are mostly related to populations, trends, and illegal trade. Population and trade data for many species was more than a decade old and might therefore not reflect the current situation for these species. Based on the species-specific detriment assessments VKM concludes no detriment for 12 species (Apodora papuana, Aspidites melanocephalus, Liasis mackloti, Malayopython reticulatus, Morelia bredli, Morelia spilota, Morelia viridis, Python anchietae, Python bivittatus, Python breitensteini, Python brongersmai, Python curtus). For one species, VKM concludes detriment (Morelia boeleni). For two species, a split conclusion is made based on the region of origin (Python regius and Python sebae). Furthermore, sufficient data was lacking for Malayopython timoriensis and VKM is therefore unable to make a detriment assessment. The final species, Python molurus, is CITES Appendix I listed and should not be traded for commercial purposes. The degree of uncertainty associated with each assessment varied based on data availability and this is indicated as a confidence level of the individual assessments (low to high)Scientific assessment of risk to populations of pythons listed by CITES as a result of tradepublishedVersio
Potential for increased connectivity between differentiated wolverine populations
Information on genetic population structure provides important knowledge for species conservation. Yet, few studies combine extensive genetic data to evaluate the structure and population dynamics of transboundary populations. Here we used single nucleotide polymorphisms (SNPs), microsatellites and mitochondrial haplotypes to analyze the genetic population structure of wolverines (Gulo gulo) across Fennoscandia using a long-term monitoring dataset of 1708 individuals. Clear population subdivision was detected between the Scandinavian and the eastern Finnish population with a steep cline in the contact zone. While the Scandinavian population showed isolation by distance, large swaths of this population were characterized by high connectivity. Areas with high resistance to gene flow are likely explained by a combination of factors, such as historical isolation and founder effects. From a conservation perspective, promoting gene flow from the population in eastern Finland to the northwest of Scandinavia could augment the less variable Scandinavian population, and increase the demographic resilience of all subpopulations. Overall, the large areas of low resistance to gene flow suggest that transboundary cooperation with aligned actions of harvest and conflict mitigation could improve genetic connectivity across Finland, Sweden, and Norway
Monitoring of species' genetic diversity in Europe varies greatly and overlooks potential climate change impacts.
Genetic monitoring of populations currently attracts interest in the context of the Convention on Biological Diversity but needs long-term planning and investments. However, genetic diversity has been largely neglected in biodiversity monitoring, and when addressed, it is treated separately, detached from other conservation issues, such as habitat alteration due to climate change. We report an accounting of efforts to monitor population genetic diversity in Europe (genetic monitoring effort, GME), the evaluation of which can help guide future capacity building and collaboration towards areas most in need of expanded monitoring. Overlaying GME with areas where the ranges of selected species of conservation interest approach current and future climate niche limits helps identify whether GME coincides with anticipated climate change effects on biodiversity. Our analysis suggests that country area, financial resources and conservation policy influence GME, high values of which only partially match species' joint patterns of limits to suitable climatic conditions. Populations at trailing climatic niche margins probably hold genetic diversity that is important for adaptation to changing climate. Our results illuminate the need in Europe for expanded investment in genetic monitoring across climate gradients occupied by focal species, a need arguably greatest in southeastern European countries. This need could be met in part by expanding the European Union's Birds and Habitats Directives to fully address the conservation and monitoring of genetic diversity
Cellular Uptake of Cationic Polymer-DNA Complexes Via Caveolae Plays a Pivotal Role in Gene Transfection in COS-7 Cells
2021 Update of the International Council for Standardization in Haematology Recommendations for Laboratory Measurement of Direct Oral Anticoagulants
International audienceIn 2018, the International Council for Standardization in Haematology (ICSH) published a consensus document providing guidance for laboratories on measuring direct oral anticoagulants (DOACs). Since that publication, several significant changes related to DOACs have occurred, including the approval of a new DOAC by the Food and Drug Administration, betrixaban, and a specific DOAC reversal agent intended for use when the reversal of anticoagulation with apixaban or rivaroxaban is needed due to life-threatening or uncontrolled bleeding, andexanet alfa. In addition, this ICSH Working Party recognized areas where additional information was warranted, including patient population considerations and updates in point-of-care testing. The information in this manuscript supplements our previous ICSH DOAC laboratory guidance document. The recommendations provided are based on (1) information from peer-reviewed publications about laboratory measurement of DOACs, (2) contributing author's personal experience/expert opinion and (3) good laboratory practice
Cellular Cytoskeleton Dynamics Modulates Non-Viral Gene Delivery through RhoGTPases
Although it is well accepted that the constituents of the cellular microenvironment modulate a myriad of cellular processes, including cell morphology, cytoskeletal dynamics and uptake pathways, the underlying mechanism of how these pathways influence non-viral gene transfer have not been studied. Transgene expression is increased on fibronectin (Fn) coated surfaces as a consequence of increased proliferation, cell spreading and active engagement of clathrin endocytosis pathway. RhoGTPases mediate the crosstalk between the cell and Fn, and regulate cellular processes involving filamentous actin, in-response to cellular interaction with Fn. Here the role of RhoGTPases specifically Rho, Rac and Cdc42 in modulation of non-viral gene transfer in mouse mesenchymal stem (mMSCs) plated in a fibronectin microenvironment was studied. More than 90% decrease in transgene expression was observed after inactivation of RhoGTPases using difficile toxin B (TcdB) and C3 transferase. Expression of dominant negative RhoA (RhoAT19N), Rac1(Rac1T17N) and Cdc42 (Cdc42T17N) also significantly reduced polyplex uptake and transgene expression. Interactions of cells with Fn lead to activation of RhoGTPases. However, further activation of RhoA, Rac1 and Cdc42 by expression of constitutively active genes (RhoAQ63L, Rac1Q61L and Cdc42Q61L) did not further enhance transgene expression in mMSCs, when plated on Fn. In contrast, activation of RhoA, Rac1 and Cdc42 by expression of constitutively active genes for cells plated on collagen I, which by itself did not increase RhoGTPase activation, resulted in enhanced transgene expression. Our study shows that RhoGTPases regulate internalization and effective intracellular processing of polyplexes that results in efficient gene transfer
A cell spot microarray method for production of high density siRNA transfection microarrays
Peer reviewe
Monitoring of speciesâ genetic diversity in Europe varies greatly and overlooks potential climate change impacts
Genetic monitoring of populations currently attracts interest in the context of the Convention on Biological Diversity but needs long-term planning and investments. However, genetic diversity has been largely neglected in biodiversity monitoring, and when addressed, it is treated separately, detached from other conservation issues, such as habitat alteration due to climate change. We report an accounting of efforts to monitor population genetic diversity in Europe (genetic monitoring effort, GME), the evaluation of which can help guide future capacity building and collaboration towards areas most in need of expanded monitoring. Overlaying GME with areas where the ranges of selected species of conservation interest approach current and future climate niche limits helps identify whether GME coincides with anticipated climate change effects on biodiversity. Our analysis suggests that country area, financial resources and conservation policy influence GME, high values of which only partially match speciesâ joint patterns of limits to suitable climatic conditions. Populations at trailing climatic niche margins probably hold genetic diversity that is important for adaptation to changing climate. Our results illuminate the need in Europe for expanded investment in genetic monitoring across climate gradients occupied by focal species, a need arguably greatest in southeastern European countries. This need could be met in part by expanding the European Unionâs Birds and Habitats Directives to fully address the conservation and monitoring of genetic diversity
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