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971.
972.
江西桃红岭梅花鹿国家级自然保护区两栖动物资源调查   总被引:3,自引:1,他引:2  
江西桃红岭梅花鹿国家级自然保护区自成立以来,一直未进行过两栖动物资源调查。为掌握两栖动物本底资源现状,评价当地的生物多样性,作者于2005年4月下旬至5月上旬、8月中旬、2006年7月下旬,前后3次对该保护区两栖动物资源进行了实地调查。保护区现已记录两栖动物19种,隶属2目7科,占江西省39种两栖动物的48.72%。其中以16种东洋界物种为主,广布种3种,无古北界物种。东洋界物种包括10种华中区与华南区共有种及6种华中区物种。这种动物区系组成特点与保护区在动物地理区划上属东洋界华中区东部丘陵平原亚区一致。此次考察增加赣北(鄱阳湖)平原省两栖动物新纪录6种,分别是中国雨蛙(Hyla chinensis)、弹琴蛙(Hylarana adenopleura)、阔褶水蛙(H.latouchii)、花臭蛙(Odorrana schmackeri)、斑腿树蛙(Rhacophorus megacephalus)和小弧斑姬蛙(Microhyla heymonsi)。最后,结合调查结果对保护区内两栖动物的分布和资源现状进行了分析。  相似文献   
973.
2019年10月,安徽省文物考古研究所在巢湖地区开展旧石器考古野外调查,新发现16处旧石器地点、1处动物化石地点,并对20世纪80年代发现的望城岗地点群进行复查,共获得石制品939件,动物化石4件。石制品原料以石英岩砾石为主,类型可划分为剥片类、废片类、修理类和砸击品。石核开发利用程度较高,周身自然砾石面占比较低;废片类包括石片、断块和碎片,石片以V型和II型为主,存在一定数量长度大于10 cm的大石片,部分石片保留直接使用痕迹;修理类多为以石片为毛坯,类型以刮削器为主,同时存在少量大型切割工具。根据对张家湾地点OSL年代学测试结果推测,巢湖地区发现旧石器地点的绝对年代不晚于距今12.5万年。这些地点的石器技术的典型特点是早期人类从大型石核上剥取大石片,并以之为毛坯加工重型工具。本次发现对进一步讨论中更新世人类在长江下游地区的石器技术多样性及该地区阿舍利技术大石片存在状况等具有重要学术意义。  相似文献   
974.
Six blood group antigens (ABO, RH, MNS, KK, KP, FY) and five plasma proteins (HP, GC, APOA4, FXIIIB, C1R) were typed in 790 individuals, and 12 mtDNA RFLP and deletion polymorphisms were typed in 657 individuals from the San Luis Valley, Colorado. The 790 nuclear typings were conducted on 399 Anglos and 391 Hispanics, while the 657 mitochondrial haplotypes were generated from 207 Anglos and 450 Hispanics. Chakraborty's ADMIX2 FORTRAN program was used to estimate the average Amerindian admixture using all nuclear loci simultaneously. Since there is no recombination in mtDNA, the sum of the frequencies of the Amerindian/Asian-specific mitochondrial haplotypes represents the level of Amerindian admixture. The nuclear estimates of Amerindian admixture were 33.15 ± 2.41% for the Hispanics and 9.72 ± 1.90% for the Anglos, while the strictly maternally inherited mtDNA estimates of Amerindian admixture were 85.11% for the Hispanics and 0.97% for the Anglos. This dramatic difference in estimated levels of admixture between the biparentally derived nuclear estimates and the uniparentally derived mtDNA estimates is indicative of past directional matings between Hispanic males and Amerindian females. Am J Phys Anthropol 102:153–159 © 1997 Wiley-Liss, Inc.  相似文献   
975.
Extensive restoration and translocation efforts beginning in the mid‐20th century helped to reestablish eastern wild turkeys (Meleagris gallopavo silvestris) throughout their ancestral range. The adaptability of wild turkeys resulted in further population expansion in regions that were considered unfavorable during initial reintroductions across the northern United States. Identification and understanding of species distributions and contemporary habitat associations are important for guiding effective conservation and management strategies across different ecological landscapes. To investigate differences in wild turkey distribution across two contrasting regions, heavily forested northern Wisconsin, USA, and predominately agricultural southeast Wisconsin, we conducted 3050 gobbling call‐count surveys from March to May of 2014–2018 and used multiseason correlated‐replicate occupancy models to evaluate occupancy–habitat associations and distributions of wild turkeys in each study region. Detection probabilities varied widely and were influenced by sampling period, time of day, and wind speed. Spatial autocorrelation between successive stations was prevalent along survey routes but was stronger in our northern study area. In heavily forested northern Wisconsin, turkeys were more likely to occupy areas characterized by moderate availability of open land cover. Conversely, large agricultural fields decreased the likelihood of turkey occupancy in southeast Wisconsin, but occupancy probability increased as upland hardwood forest cover became more aggregated on the landscape. Turkeys in northern Wisconsin were more likely to occupy landscapes with less snow cover and a higher percentage of row crops planted in corn. However, we were unable to find supporting evidence in either study area that the abandonment of turkeys from survey routes was associated with snow depth or with the percentage of agricultural cover. Spatially, model‐predicted estimates of patch‐specific occupancy indicated turkey distribution was nonuniform across northern and southeast Wisconsin. Our findings demonstrated that the environmental constraints of turkey occupancy varied across the latitudinal gradient of the state with open cover, snow, and row crops being influential in the north, and agricultural areas and hardwood forest cover important in the southeast. These forces contribute to nonstationarity in wild turkey–environment relationships. Key habitat–occupancy associations identified in our results can be used to prioritize and strategically target management efforts and resources in areas that are more likely to harbor sustainable turkey populations.  相似文献   
976.
Fecal microbial biomarkers represent a less invasive alternative for acquiring information on wildlife populations than many traditional sampling methodologies. Our goal was to evaluate linkages between fecal microbiome communities in Rocky Mountain elk (Cervus canadensis) and four host factors including sex, age, population, and physical condition (body‐fat). We paired a feature‐selection algorithm with an LDA‐classifier trained on elk differential bacterial abundance (16S‐rRNA amplicon survey) to predict host health factors from 104 elk microbiomes across four elk populations. We validated the accuracy of the various classifier predictions with leave‐one‐out cross‐validation using known measurements. We demonstrate that the elk fecal microbiome can predict the four host factors tested. Our results show that elk microbiomes respond to both the strong extrinsic factor of biogeography and simultaneously occurring, but more subtle, intrinsic forces of individual body‐fat, sex, and age‐class. Thus, we have developed and described herein a generalizable approach to disentangle microbiome responses attributed to multiple host factors of varying strength from the same bacterial sequence data set. Wildlife conservation and management presents many challenges, but we demonstrate that non‐invasive microbiome surveys from scat samples can provide alternative options for wildlife population monitoring. We believe that, with further validation, this method could be broadly applicable in other species and potentially predict other measurements. Our study can help guide the future development of microbiome‐based monitoring of wildlife populations and supports hypothetical expectations found in host‐microbiome theory.  相似文献   
977.
A survey of ecosystem research in brackish coastal waters (Baltic Sea) by the Department of Biology, University Rostock (GDR) is given. Using selected results the main goals are demonstrated, outgoing from the first steps initiated by W. Schnese.  相似文献   
978.
Pneumocystis (P.) carinii is known to cause fatal pneumonia in immunocompromised rats. Cases of P. carinii interstitial pneumonia in immunocompetent rats have been shown histologically to present with perivascular lymphoid cuffs, which have previously been attributed to rat respiratory virus. This study aims to determine the prevalence and pathological characteristics of P. carinii in immunocompetent laboratory rats in experimental facilities in Japan. An epidemiological survey for this agent was performed using PCR to assess 1,981 immunocompetent rats from 594 facilities in Japan. We observed that 6 of the 1,981 rats (0.30%) from 4 out of 594 facilities (0.67%) were positive for P. carinii without infection of other known pathogens. Gross pulmonary lesions were found in 4 of the 6 affected rats. The lungs of these rats contained scattered dark red/gray foci. Histopathologically, the lungs exhibited interstitial pneumonia with lymphoid perivascular cuffs: Pneumocystis cysts were observed using Grocott’s methenamine silver stain. To our knowledge, this report is the first to reveal the prevalence of natural P. carinii infection in immunocompetent laboratory rats in Japan.  相似文献   
979.
评价濒危植物四合木(Tetraena mongolica)基因组的大小及复杂程度,开展基因组研究可揭示四合木的超旱生机制,进一步挖掘其特色基因资源。为更好破解四合木的全基因组信息,采用第二代高通量测序技术的基因组Survey分析技术开展四合木基因组大小估测研究,并利用生物信息学方法估计了四合木杂合率、重复序列和GC含量等基因组信息。结果表明:四合木基因组大小为1 079.25 Mb,修正后的基因组大小为1 065.84Mb,杂合率为0.76%,重复序列比例为75.25%,GC含量为33.57%。在经过四合木基因组初步组装后,获得3502 126条contigs,总计682 Mb,其N50为187 bp,推测四合木基因组属于同源四倍体复杂基因组,全基因组测序组装难度较大。由于四合木的高杂合率,后续可采用第三代高通量测序技术(单分子测序)同时结合染色质区域捕获技术,有望最终获得高质量的四合木全基因图谱。  相似文献   
980.
[Purpose]Functional beverages are intended to support those who want to maintain optimal physical condition and improve their quality of life through the enhancement of heart health, immunity, and digestion. The purpose of this study was to investigate the performance of top-level athletes consuming immune-strengthening conditioning nutritional drinks.[Methods]A total of 107 top-level athletes (baseball (56 players), pro volleyball (17), athletics (16), cycling (8), golf (6), and fencing (6)) participated in the experiment. They consumed an immune-enhancing functional beverage once a day for 8 weeks and responded to a survey before, during, and after drinking the beverage.[Results]Three total aspect-based subfactors were drawn from 24 questions in the factor analysis: physical, satisfaction with mental stability, and activity in performance. The physical, mental stability and performance changes of athletes significantly increased in period 2 (4 weeks after intake) and period 3 (after 8 weeks of intake).[Conclusion]We evaluated the efficacy of a new conditioned beverage containing Lactobacillus B240 and protein in improving the performance and physiological utility of top athletes. This functional drink may gain popularity among those seeking health benefits and improved exercise performance.  相似文献   
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