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Using data on waterfowl band recoveries, we identified spatially explicit hotspots of concentrated waterfowl movement to predict occurrence and spatial spread of a novel influenza A virus (clade 2.3.4.4) introduced from Asia by waterfowl from an initial outbreak in North America in November 2014. In response to the outbreak, the hotspots of waterfowl movement were used to help guide sampling for clade 2.3.4.4 viruses in waterfowl as an early warning for the US poultry industry during the outbreak . After surveillance sampling of waterfowl, we tested whether there was greater detection of clade 2.3.4.4 viruses inside hotspots. We found that hotspots defined using kernel density estimates of waterfowl band recoveries worked well in predicting areas with higher prevalence of the viruses in waterfowl. This approach exemplifies the value of ecological knowledge in predicting risk to agricultural security.  相似文献   
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The earliest credible evidence of Homo sapiens in Europe is an archaeological proxy in the form of several artifact assemblages (Bohunician) found in South-Central and possibly Eastern Europe, dating to ≤48,000 calibrated radiocarbon years before present (cal BP). They are similar to assemblages probably made by modern humans in the Levant (Emiran) at an earlier date and apparently represent a population movement into the Balkans during a warm climate interval [Greenland Interstadial 12 (GI 12)]. A second population movement may be represented by a diverse set of artifact assemblages (sometimes termed Proto-Aurignacian) found in the Balkans, parts of Southwest Europe, and probably in Eastern Europe, and dating to several brief interstadials (GI 11–GI 9) that preceded the beginning of cold Heinrich Event 4 (HE4) (≈40,000 cal BP). They are similar to contemporaneous assemblages made by modern humans in the Levant (Ahmarian). The earliest known human skeletal remains in Europe that may be unequivocally assigned to H. sapiens (Peçstera cu Oase, Romania) date to this time period (≈42,000 cal BP) but are not associated with artifacts. After the Campanian Ignimbrite volcanic eruption (40,000 cal BP) and the beginning of HE4, artifact assemblages assigned to the classic Aurignacian, an industry associated with modern human skeletal remains that seems to have developed in Europe, spread throughout the continent.  相似文献   
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本研究采用昆虫分类学原理和方法,对欧亚地区厕蝇科厕蝇属夏厕蝇种团Fannia canicularis-group进行了系统分类研究.欧亚地区夏厕蝇种团昆虫共30种,分别隶属于夏厕蝇亚种团Fannia canicularissubgroup(20种),巨尾厕蝇亚种团Fannia lucidula-subgroup(7种),白纹厕蝇亚种团Fannia leucostictasubgroup(3种),编制了“欧亚地区厕蝇属夏厕蝇种团名录”,详细描述了其国内外分布情况,并对部分外国种类新拟了中文名.  相似文献   
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Specimens archived in wet collections represent valuable material for scientific research. Here, we show that bat fly (Diptera, Nycteribiidae) samples contain DNA of Pseudogymnoascus destructans , a fungus pathogenic to bats. Using dual‐probe quantitative PCR , we detected P. destructans DNA on bat flies collected in the Samara, Sverdlovsk and Irkutsk regions of Russia between 2005 and 2017. Fungal load was significantly lower on bat flies from wet collections than on freshly collected mites in the Czech Republic. The bat pathogen was present in the Samara region (European part of Russia) in 2005, that is, a year before recognition of white‐nose syndrome in North America. As Samara and Irkutsk regions were identified as new positive locations of P. destructans , our data expand the known geographic distribution of P. destructans . We conclude that ethanol‐stored ectoparasites can be used to identify the presence of pathogens in historic bat populations and understudied geographical regions.  相似文献   
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The genetic structure of populations of Turnip mosaic virus in Eurasia was assessed by making host range and gene sequence comparisons of 142 isolates. Most isolates collected in West Eurasia infected Brassica plants whereas those from East Eurasia infected both Brassica and Raphanus plants. Analyses of recombination sites (RSs) in five regions of the genome (one third of the full sequence) showed that the protein 1 (P1 gene) had recombined more frequently than the other gene regions in both subpopulations, but that the RSs were located in different parts of the genomes of the subpopulations. Estimates of nucleotide diversity showed that the West Eurasian subpopulation was more diverse than the East Eurasian subpopulation, but the Asian-BR group of the genes from the latter subpopulation had a greater nonsynonymous/synonymous substitution ratio, especially in the P1, viral genome-linked protein (VPg) and nuclear inclusion a proteinase (NIa-Pro) genes. These subpopulations seem to have evolved independently from the ancestral European population, and their genetic structure probably reflects founder effects.  相似文献   
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Plant pathogens have agricultural impacts on a global scale and resolving the timing and route of their spread can aid crop protection and inform control strategies. However, the evolutionary and phylogeographic history of plant pathogens in Eurasia remains largely unknown because of the difficulties in sampling across such a large landmass. Here, we show that turnip mosaic potyvirus (TuMV), a significant pathogen of brassica crops, spread from west to east across Eurasia from about the 17th century CE. We used a Bayesian phylogenetic approach to analyze 579 whole genome sequences and up to 713 partial sequences of TuMV, including 122 previously unknown genome sequences from isolates that we collected over the past five decades. Our phylogeographic and molecular clock analyses showed that TuMV isolates of the Asian-Brassica/Raphanus (BR) and basal-BR groups and world-Brassica3 (B3) subgroup spread from the center of emergence to the rest of Eurasia in relation to the host plants grown in each country. The migration pathways of TuMV have retraced some of the major historical trade arteries in Eurasia, a network that formed the Silk Road, and the regional variation of the virus is partly characterized by different type patterns of recombinants. Our study presents a complex and detailed picture of the timescale and major transmission routes of an important plant pathogen.

Eurasia is the largest landmass on Earth and has a rich demographic, cultural, and economic history. It was one of the birthplaces of agriculture and hosts the richest variety of crops, including vegetable crops (13). Eurasia is also the likely area of origin of many plant pathogens (46), but there have been few detailed studies of exactly when and where these pathogens emerged. Possibly owing to a lack of genetic sequence data, there also remains a poor understanding of the migration pathways of plant viruses and other plant pathogens in Eurasia.Turnip mosaic potyvirus (TuMV) is probably the most widespread and important plant virus and occurs throughout subtropical and temperate regions (7). It mainly damages dicotyledonous domestic brassica crops, which are important food vegetables and were probably developed from wild Brassica plants by plant breeders during the expansion of agriculture. First described from brassica crops in 1921 in the United States (8, 9), TuMV has been ranked behind only cucumber mosaic cucumovirus as the most important virus infecting field-grown vegetables (10, 11).Brassica vegetables, the main host plants of TuMV in modern agriculture (7, 10), mostly originated in the Mediterranean and Western Eurasia (12, 13). These economically important plants are commonly known as cabbages or mustard plants and include turnip, cauliflower, and broccoli. A possible wild ancestor of cabbage was originally found in Western and Southern Europe (14). Brassica vegetables then spread to East Asia, including Japan and Korea, while the first record of the cultivation of Chinese cabbage dates from the 15th century CE. The edible radish (Raphanus sativus) possibly originated from ancestral wild radish (Raphanus raphanistrum) in the Mediterranean region and was domesticated in Asia prior to Roman times (15).Within the genus Potyvirus (family Potyviridae), TuMV is closely related to viruses from monocotyledonous narcissus, scallion, wild onion, and yam to form the TuMV phylogenetic group (1619). Potyviruses infect a wide range of flowering plants (16, 19, 20) and are spread by aphids in a nonpersistent manner and sometimes in seeds and infected living plant materials. They have a genome that is a single-stranded, positive-sense RNA of ∼10,000 nucleotides (nt). The genome has one major open reading frame (ORF), which is translated into one large polyprotein, and a small overlapping ORF, a “pretty interesting Potyviridae ORF” (21). The polyprotein is autocatalytically hydrolyzed into at least 10 mature proteins (19, 22).In terms of its evolution and epidemiology, the potyvirus TuMV is among the best studied of the plant-infecting RNA viruses. We have shown that it probably originated from a virus of wild orchids in Europe (7, 23). While adapting to wild and domestic Brassicaceae plants, TuMV spread from its center of emergence in Southern Europe, Asia Minor, and the Middle East to other parts of the world, including East Asia (2427), Oceania (28), and the Americas (7, 29). However, the evolution and epidemiology of this virus in Eurasia remain poorly studied, leaving considerable uncertainty about its past migration pathways and its evolutionary dynamics and timescale.In this study, we collected TuMV isolates from locations throughout Eurasia, including countries neighboring the center of emergence. We examined the biological characteristics of viral isolates that had been sampled from these countries across half a century of growing seasons. By analyzing 579 whole genome sequences, we estimated the evolutionary rate and timescale of TuMV and inferred its phylodynamic and phylogeographic history. Our study presents one of the largest and most detailed evolutionary and epidemiological analyses of a plant pathogen, providing a comprehensive picture of the temporal and spatial spread of a major plant pathogen across Eurasia.  相似文献   
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During every criminal investigation, it is vital to extract as much information as possible from every piece of evidence. When it comes to DNA testing, simple short tandem repeat (STR) typing may soon become a relic because it is now possible to genotype more characteristics. Ancestry informative markers are receiving attention from the forensic community because individuals can be assigned to their population or territory of origin based on their analysis. Many panels of this kind have been proposed so far, yet most of them require typing of a large number of loci. In many cases it is crucial to pick a minimal set of the most informative markers due to the limited amount of material available for analysis. In this study, we demonstrate that 14 carefully picked SNPs combined in two multiplex assays are capable of fast, robust and cost effective three-way differentiation of East Asians, Europeans and Africans.  相似文献   
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