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51.
The nomadic Romani (gypsy) people are known for their deep-rooted traditions, but most of their history is recorded from external sources. We find evidence for a Romani genetic lineage in England long before their recorded arrival there. The most likely explanations are that either the historical record is wrong, or that early liaisons between Norse and Romani people during their coincident presence in ninth to tenth century Byzantium led to the spread of the haplotype to England.  相似文献   
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The chemical investigation of the methanolic extract of the root bark of Waltheria douradinha (Sterculiaceae) afforded an unusual quinolinone alkaloid named waltherione-A (1). Its structure was determined mainly by NMR spectroscopic methods. The antibacterial activity of waltherione-A (1) and the corresponding O-methylated derivative (2) was tested against three gram-negative and three gram-positive bacteria, with only (2) having moderate activity.  相似文献   
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Introduction  

The objective of this study was to determine whether serum biomarkers for degradation and synthesis of the extracellular matrix of cartilage are associated with, and can predict, radiographic damage in patients with rheumatoid arthritis (RA).  相似文献   
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For most neurodegenerative diseases the precise duration of an individual cell''s death is unknown, which is an obstacle when counteractive measures are being considered. To address this, we used the rd1 mouse model for retinal neurodegeneration, characterized by phosphodiesterase-6 (PDE6) dysfunction and photoreceptor death triggered by high cyclic guanosine-mono-phosphate (cGMP) levels. Using cellular data on cGMP accumulation, cell death, and survival, we created mathematical models to simulate the temporal development of the degeneration. We validated model predictions using organotypic retinal explant cultures derived from wild-type animals and exposed to the selective PDE6 inhibitor zaprinast. Together, photoreceptor data and modeling for the first time delineated three major cell death phases in a complex neuronal tissue: (1) initiation, taking up to 36 h, (2) execution, lasting another 40 h, and finally (3) clearance, lasting about 7 h. Surprisingly, photoreceptor neurodegeneration was noticeably slower than necrosis or apoptosis, suggesting a different mechanism of death for these neurons.  相似文献   
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Policy makers and managers are increasingly called upon to assess the state of biodiversity, and make decisions regarding potential interventions. Genetic tools are well-recognised in the research community as a powerful approach to evaluate species and population status, reveal ecological and demographic processes, and inform nature conservation decisions. The wealth of genetic data and power of genetic methods are rapidly growing, but the consideration of genetic information and concerns in policy and management is limited by the currently low capacity of decision-makers to access and apply genetic resources. Here we describe a freely available, user-friendly online resource for decision-makers at local and national levels (http://congressgenetics.eu), which increases access to current knowledge, facilitates implementation of studies and interpretation of available data, and fosters collaboration between researchers and practitioners. This resource was created in partnership with conservation practitioners across the European Union, and includes a spectrum of taxa, ecosystems and conservation issues. Our goals here are to (1) introduce the rationale and context, (2) describe the specific tools (knowledge summaries, publications database, decision making tool, project planning tool, forum, community directory), and the challenges they help solve, and (3) summarise lessons learned. This article provides an outlook and model for similar efforts to build policy and management capacity.  相似文献   
58.
Species that evolved in temperate regions during the Pleistocene experienced periods of extreme climatic transitions. Consequent population fragmentation and dynamics had the potential to generate small, isolated populations where the influence of genetic drift would be expected to be strong. We use comparative genomics to assess the evolutionary influence of historical demographics and natural selection through a series of transitions associated with the formation of the genus Capreolus, speciation within this genus during the Quaternary and during divergence among European roe deer (C. capreolus) populations. Our analyses were facilitated by the generation of a new high‐coverage reference genome for the Siberian roe deer (C. pygargus). We find progressive reductions in effective population size (Ne), despite very large census sizes in modern C. capreolus populations and show that low Ne has impacted the C. capreolus genome, reducing diversity and increasing linkage disequilibrium. Even so, we find evidence for natural selection shared among C. capreolus populations, including a historically documented founder population that has been through a severe bottleneck. During each phylogenetic transition there is evidence for selection (from dN/dS and nucleotide diversity tests), including at loci associated with diapause (delayed embryonic development), a phenotype restricted to this genus among the even‐toed ungulates. Together these data allow us to assess expectations for the origin and diversification of a mammalian genus during a period of extreme environmental change.  相似文献   
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We investigated hierarchical patterns of genetic subdivision, and assessed kinship within and between social groups of striped dolphins (Stenella coeruleoalba) in the Tyrrhenian Sea. A total of 165 samples were analysed at eight microsatellite DNA loci, including outgroup samples from the Adriatic, Scotland and Spain for population-level comparisons. We found population genetic structure within the Mediterranean basin, including small but significant differentiation between the Adriatic and Tyrrhenian Seas (FST=0.0047, P=0.008), and between putative 'inshore' and 'offshore' (FST=0.0217, P=0.005) populations in the Tyrrhenian Sea. Assessment of kinship within and among 12 association groups showed higher average kinship for females within than between groups, and smaller groups showed higher average kinship. Comparisons of relatedness for both sexes showed a significant difference between males and females, with females more likely to associate with adult kin. Together these data emphasize the importance of the social cohesion of kin in small groups to the structuring of striped dolphin populations in this environment.  相似文献   
60.
A number of dolphin species, though highly mobile, show genetic structure among parapatric and sometimes sympatric populations. However, little is known about the temporal patterns of population structure for these species. Here, we apply Bayesian inference and data from ancient DNA to assess the structure and dynamics of bottlenose dolphin (Tursiops truncatus) populations in the coastal waters of the UK. We show that regional population structure in UK waters is consistent with earlier studies suggesting local habitat dependence for this species in the Mediterranean Sea and North Atlantic. One genetically differentiated UK population went extinct at least 100 years ago and has not been replaced. The data indicate that this was a local extinction, and not a case of historical range shift or contraction. One possible interpretation is a declining metapopulation and conservation need for this species in the UK.  相似文献   
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