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1.
1997年冬季在海南省松涛水库发现 1 0 0多只鸢集群 ,鸢群出现位置为 1 0 9°39′E ,1 9°1 9′N ,出现的时间大约在 1 7:30时后 ,直到天黑 ,成群的鸢在山顶和水库的上空盘旋 ,持续时间长达 30多分钟。 1 998年 1 1月、1 2月及 1 999年 2月 ,还在这里发现鸢群 ,并在 1 999年 2月观察到鸢在该地筑巢。  相似文献   

2.
Thesystematics of the genus Gobio, especially of the populations on the southern Black Sea coast, seems to be still far from being resolved. Seven species were rec-orded from the northern Black Sea coast while three species were recognized from the southern Black Sea coast. We examined in total 43 specimens from K?z?l?rmak River (southern Black Sea basin), 80 specimens from Çoruh River (the Western Cau-casus of the Black Sea basin), 14 specimens from Rioni River (the Western Caucasus of the Black Sea basin), and 6 specimens from Kherota and Shakhe Rivers (the Western Caucasus of the Black Sea basin). Based on an analysis of 32 metric and 5 meristic data as well as the number of vertebrae, we concluded that the K?z?l?rmak and Coruh populations are two distinct, unnamed species, and we describe them here as Gobio kizilirmakensis from the K?z?l?rmak River and G. artvinicus from the Çoruh River.

http://www.zoobank.org/urn:urn:lsid:zoobank.org:pub:1ED54FB1-588F-4412-B376-4BE4E4516EB1  相似文献   

3.
Introduction: Work-related stress (WRS) and posttraumatic disorder (PTSD) is higher among Black adults relative to their White counterparts. Trauma exposure is not the only connection to increased risk for PTSD as WRS is highly associated with risk for PTSD. However, the factors that link WRS and PTSD among working Black adults is not well understood. Materials and Methods: Cross-sectional data from the National Survey of American Life was used to examine the relationship between WRS and PTSD among 2,139 working Black adults and to determine whether there are influencing factors. Results: Logistic regression analyses revealed that working Black adults who reported experiencing WRS was associated with higher odds of PTSD than those who reported no WRS (OR: 1.24, 95% CI: 1.04-1.48). The relationship was attenuated when depression, alcohol abuse, and major discrimination were added to the model (OR: 1.09, 95% CI: 0.87-1.36). Mediation analyses show that the average indirect effect of WRS on PTSD were 0.09 ± 0.04 for alcohol abuse, 0.14 ± 0.06 for depression, and 0.35 ± 0.10 for major discrimination. Conclusion: The results underscore the need for culturally responsive trauma-informed public health interventions for working Black adults. Public health practitioners should be alerted to the relationship between WRS and PTSD among working Black adults and the potential contributing factors (alcohol abuse, depression, and major discrimination). Special attention should be given to working Black females with their worse PTSD status and major discrimination experiences which demonstrated greater effect on the relationship between WRS and PTSD.  相似文献   

4.
目的:测定务川黑牛mtDNA D-loop区全序列,以了解其遗传背景。方法:采用PCR直接测序方法测定务川黑牛mtD-NA D-loop区全序列。结果:32个个体D-loop区的全序列中,四种碱基A、T、C和G含量分别为:33.1%、28.4%、25.0%和13.5%,A+T平均含量61.5%。经过序列比对,共检测到57个变异位点,占所测mtDNA序列总长的6.26%,其中转换54个,颠换3个;产生17种单倍型,其中6种是普通牛单倍型,11种是瘤牛单倍型;平均核苷酸差异为22.623,单倍型多样度0.901±0.039,核苷酸多样度0.0249±0.00147。结论:务川黑牛这一品种遗传多样性非常丰富,据此构建的NJ进化树显示务川黑牛含有普通牛和瘤牛的血统。  相似文献   

5.
Birth statistics for the Johannesburg Metropolitan Region were collected for 757 151 confinements from 1969 to 1989 (467513 Black, 194375 White, 67250 Coloured and 28013 Indian confinements). From 1969 to 1978 data on the sexes of twins were also collected for 375 203 of the confinements (203 504 Black, 129 631 White, 28 253 Coloured and 13 815 Indian confinements). A twin confinement was defined as two deliveries during one confinement. Twinning rates (TRs), defined as the number of twin confinements per 1000 total confinements, were calculated per year for each population group and from 1969-1978 estimates of the relative proportions of dizygotic (DZ) and monozygotic (MZ) twins were calculated and thus the relative DZTRs and MZTRs. A significant decline in Black and Coloured TRs was observed between 1969 and 1989. A significant decline in Black DZTR but not Black MZTR was observed between 1969 and 1978, the Coloured twin sample was too small to show significant trends over this period. It is probable that the overall decline in Black twinning may be explained by a decline in the DZTR. An analysis of birth statistics for 159 748 confinements (134 504 Black and 25 244 White confinements) collected as part of a prospective study of TRs in the Johannesburg Metropolitan Region from 1988 to 1990, indicated that the Black TR continued to decline at least until the end of 1990. TRs in the Johannesburg Metropolitan Region calculated from City Health Department birth statistics collected from 1988 to 1990 were: 13.8 and 10.77 for the Black and White populations, respectively. TRs for this period calculated from the combined birth statistics of 14 hospitals, nursing homes and maternity clinics across the region were: 12.4 and 10.88 for the Black and White populations, respectively.  相似文献   

6.
Capsule: Black Grouse population increases were greatest where new native woodland (NNW) within 1500?m of leks comprised approximately 30% of land area and averaged 5 years old.

Aims: To examine whether change in a population of Black Grouse Lyrurus tetrix in Scotland was associated with the creation of native woodland.

Methods: We examined whether lek location, size and change in size were associated with habitat and topography surrounding leks. We also examined vegetation differences in NNW and adjacent unplanted moorland.

Results: From 2002 to 2012 the number of lekking male Black Grouse increased by 90%. Lek occurrence was positively associated with the amount of NNW edge habitat. Leks were larger where there was more adjacent NNW. Lek increases were greatest where NNW plots comprised approximately 30% land area, and were 5 years old, within a 1500?m radius. Plots aged more than approximately 20 years old were associated with Black Grouse population declines. NNW supported taller and denser important field-layer vegetation than adjacent moorland, likely due to grazing exclusion.

Conclusions: Subject to longer-term management commitments to stimulate continued regrowth of the important field layer and maintain benefits for Black Grouse, expansion of native woodland could contribute to landscape-scale recovery of Black Grouse after decades of decline.  相似文献   

7.
Summary DNA patterns from a pseudoautosomal variable number tandem repeat-like minisatellite (locus DXYS20) were compared in two samples: a Caucasian and a Black sample. We defined 3 types of DNA patterns named A, B and C, and found that these patterns have different frequencies in the Caucasian and Black groups. A set of alleles (the C group) in 48% of the Black sample is not found in the Caucasian sample. We also found a greater degree of fragment-size variability among Black individuals than among those of Caucasian origin. The large degree of ethnic variation indicates that this locus will be useful in population genetic studies.  相似文献   

8.
In our reading of Chocolate Cities: The Black Map of American Life as a work of liberation sociology, we discuss contributions to Black critical thought and praxis this book uniquely makes. Hunter and Robinson craft a Black-owned analytical approach by rezoning the United States map into a charting of African American social and cultural milestones. To apply the re-centering methodological and theoretical innovations this book encourages, we extend its themes to the contested racialized terrains of literacy and education in the US. One contemporary response to systemic educational racism, Black homeschooling, is reconceptualized as a resistance movement. Inspired by the provocative work Hunter and Robinson have done, we situate the Black homeschooling within the tradition of critical Black thought, and its enduring emancipatory warrant.  相似文献   

9.
We examined the extent of linkage disequilibrium (LD) block lengths in four breed populations: Japanese Black, Angus, Hereford and Holstein. Three chromosomal regions in which QTL were previously mapped in Japanese Black populations were scanned with 84 microsatellite markers. The estimated LD lengths in these four purebred populations varied from 535 to 683 kb, which is much shorter than the values reported previously. Our findings suggest that QTL can be mapped in sub-centimorgan regions in these populations using an LD-mapping method. We also developed breed identification methods to distinguish Japanese Black from Angus, Hereford, Holstein and F1 animals (Japanese Black × Holstein) respectively using the haplotypic frequencies of a pair of markers in the breed populations. After assessing the distributions of posterior probabilities to be Japanese Black, we obtained several pairs of markers that completely distinguished Japanese Black from the other breeds. We also obtained several combinations of six markers that completely distinguished Japanese Black animals from F1 animals.  相似文献   

10.
张银运  邢松 《人类学学报》2011,30(3):241-249
周口店直立人3号头骨是1929年发现的, 被步达生鉴定为一青春期或成年期的女性个体的头骨。后来, 步达生改变了观点, 认为该头骨是代表青春期早期的男性个体。魏敦瑞同意步达生的意见, 但认为该头骨应属于8岁或9岁的男性个体。此后,周口店直立人3号头骨的性别和年龄的鉴定一直困扰着许多古人类学家。1993年发现的南京直立人成年女性头骨在形态上和尺寸上与周口店直立人3号头骨有相近之处。本文对周口店直立人3号头骨与南京直立人等头骨作了形态和测量上的比较, 结果表明: 从头骨的尺寸大小, 眶上圆枕、枕圆枕和肌嵴的发育程度以及头骨骨壁厚度等来看, 周口店3号头骨有理由被认为是女性个体的。该头骨的鼓骨裂、下颌骨关节窝、泪腺窝、额窦、骨缝等都无法证明其是幼年个体。周口店直立人3号头骨应代表成年女性个体。  相似文献   

11.
Group Harmony: The Black Urban Roots of Rhythm and Blues. Stuart L. Goosman. Philadelphia: University of Pennsylvania Press, 2005. 291 pp.
Right to Rock: The Black Rock Coalition and the Cultural Politics of Race. Maureen Mahon. Durham, NC: Duke University Press, 2004. 317 pp.
Crossovers: Essays on Race, Music, and American Culture. John Szwed. Philadelphia: University of Pennsylvania Press, 2005. 283 pp.  相似文献   

12.
U.S. Black women have higher breast cancer mortality compared to White women while their rate of ever having a mammogram has become equal to or slightly surpassed that of Whites. We mapped the distribution of change in screening mammography for Black and White female Medicare enrollees ages 67–69 from 2008 to 2012 by hospital referral region across the contiguous U.S., performed cluster analysis to assess spatial autocorrelation, and examined the screening differences between these groups in 2008 and 2012 respectively. Changes in screening mammography are not consistent across the U.S.: Black and White women have increased and decreased their use of mammography in different regions and Black women’s change patterns vary more widely.  相似文献   

13.
Capsule: In the Scottish Highlands, Black Grouse Tetrao tetrix females with young broods selected areas rich in wet flushes, grasses and Sphagnum mosses.

Aims: To identify associations between young Black Grouse broods and habitat characteristics.

Methods: We located brood-rearing Black Grouse females in four areas of moorland-forest mosaic in the Scottish Highlands. Each brood was paired with a random reference location 100?m away. We recorded cover of different habitats and fine-scale vegetation and structure within squares of 1 and 0.25?ha, respectively. Associations between brood occurrence and habitat and vegetation variables were examined at the two scales.

Results: Black Grouse broods were positively associated with wet flushes (1?ha), and with Heather Calluna vulgaris, sedges Carex spp., grasses, Sphagnum mosses and taller vegetation with intermediate levels of height variability (0.25?ha).

Conclusions: This study highlights the importance of wet habitats for young Black Grouse chicks. In addition, relatively tall field-layer vegetation comprising Heather, sedges, grasses over a layer of Sphagnum mosses attracted brood-rearing Black Grouse females. Many management practices associated with peatland restoration, including drain-blocking, Sphagnum re-establishment and the avoidance of burning on deep peat soils, are therefore consistent with favourable habitat management for Black Grouse.  相似文献   


14.
Eight novel and four known mutations were detected in the coding sequence of the bovine fatty acid synthase (FASN) gene of an F2 population from Japanese Black and Limousin cattle. Two mutations, g.16024A>G and g.16039T>C, detected in exon 34, which determine amino acid substitutions of threonine (T) to alanine (A) and tryptophan (W) to arginine (R), were clearly separated in the parental breeds. The haplotypes (TW and AR) segregated in F2 individuals and had a significant effect on the fatty acid composition of backfat, intermuscular fat, and intramuscular fat. The TW haplotype was associated with increasing C18:0 and C18:1 content and the ratio of monounsaturated to saturated fatty acids, and decreasing C14:0, C14:1, C16:0, and C16:1 content. The two mutations were screened in two commercial Japanese Black half-sibling populations and similarly determined the contribution to the fatty acid composition of intramuscular fat. The frequency of the TW haplotype was markedly higher in Japanese Black (0.67) than in Holstein (0.17), Angus (0.02), and Hereford (0.07). We conclude that these mutations may contribute to the characteristic fatty acid composition of Japanese Black beef.  相似文献   

15.
Previous research reveals that a more 'African' appearance has significant social consequences, yielding more negative first impressions and harsher criminal sentencing of Black or White individuals. This study is the first to systematically assess the relative contribution of skin tone and facial metrics to White, Black, and Korean perceivers' ratings of the racial prototypicality of faces from the same three groups. Our results revealed that the relative contribution of metrics and skin tone depended on both perceiver race and face race. White perceivers' racial prototypicality ratings were less responsive to variations in skin tone than were Black or Korean perceivers' ratings. White perceivers ratings' also were more responsive to facial metrics than to skin tone, while the reverse was true for Black perceivers. Additionally, across all perceiver groups, skin tone had a more consistent impact than metrics on racial prototypicality ratings of White faces, with the reverse for Korean faces. For Black faces, the relative impact varied with perceiver race: skin tone had a more consistent impact than metrics for Black and Korean perceivers, with the reverse for White perceivers. These results have significant implications for predicting who will experience racial prototypicality biases and from whom.  相似文献   

16.
Chocolate Cities is a work of Black urban studies, treating the entire US as a variegated “South.” Despite regional differences the US retains its endemic white supremacism. Based on this recognition, the authors argue, it is necessary to reimagine and revaluate the breadth and depth of Blackness throughout the country. The authors proceed virtually to reinvent Black urban sociology and thoroughly to reinterpret Black cultural studies. In doing so they challenge US census data and much of the sociology of race, as well as drawing on a wealth of intellectual, political, and popular cultural resources that explore the breadth and depth of Black peoplehood. In many ways, Chocolate Cities returns us to the Black nationalist framework: W. E. B. Du Bois, Malcolm X, Zora Neale Hurston, Ida B. Wells Barnett, Aretha Franklin, and Tupac Shakur all appear here, as do intersectionality studies, LGBT activism, and the Movement for Black Lives.  相似文献   

17.
6. SHORT NOTES     
Schmitt, M. B. 1975. Observations on the Black Crake in the Southern Transvaal. Ostrich 46:129-138.

During a four-year study period, several pairs of Black Crakes Porzana flavirostris and their progeny have been studied on a vlei in the southern Transvaal. Morphological differences between male and female are discussed, a double-brooded breeding season is indicated, the development of chicks is described, and the moult cycle is indicated. The Black Crake moults all flight feathers simultaneously and during its breeding season.  相似文献   

18.
马铃薯(Solanum tuberosum)是一种重要的粮菜兼用型作物,马铃薯传入我国后产生了许多变种、变型和适合当地种植的地方品种,尤其是块茎的皮色和肉色出现了红色、紫色、黑色品种。"黑美人"马铃薯是甘肃省特有的经航空育种技术培育的新型马铃薯品种,经分析测定"黑美人"马铃薯中花色素含量非常丰富,其富含的花青素还具有抗癌、抗衰老、美容和防止高血压等多种保健作用。因此,"黑美人"马铃薯中花色苷提取工艺的研究,对于花色苷的应用与开发具有重要的研究意义。本研究以甘肃"黑美人"马铃薯为原料,对其所含花色苷提取工艺条件(乙醇浓度,温度,pH,提取时间,料液比,提取次数等)进行优化。研究结果显示最佳提取工艺参数为:乙醇浓度80%,温度75℃,pH 1.0,时间1 h,料液比1:20,提取3次。在优化后的提取工艺条件下,"黑美人"马铃薯的花色苷提取率得到提高,花色苷含量可达到33.05 mg/100g。  相似文献   

19.
Book review     

The Black Trans‐Atlantic Experience Marc, Stephen, The Black Trans‐Atlantic Experience: Street Life and Culture in Ghana, Jamaica, England and the United States. Photographs by Stephen Marc; Foreword by Marilyn Houlberg; Interview by Alan Cohen. Chicago: Columbia College and the University of Illinois Press, 1992, 160 pp., illus., $49.95.  相似文献   

20.
The Black Caribs “Garifuna” originated on St. Vincent Island, in the West Indies, as a cultural and biological amalgam between Amerindians “Arawak and Island Caribs” and West Africans. A total of 2,026 of the Black Caribs were deported by the British in 1797 to the Bay Islands, from which they further emigrated to Honduras, Central America. The Garifuna provide an example of evolutionary success by a colonizing population with one of the highest observed fertility levels “a mean of 10.9 children per woman 45 years of age or older” in the world. The Central American Black Carib population has increased from fewer than 2,000 persons in 1800 to approximately 70,000 at present. It has been estimated that an additional 20,000 Black Caribs have immigrated to England, the United States, and other parts of the world. This review focuses upon the observed genetic variation and population structure of the Black Caribs. The population structure is characterized by a series of fissions and fusions of the gene pool. Fusion and genetic hybridization play a major role in the early development of this society. Subdivision of the hybrid gene pool occurs as the Black Caribs colonize the coast of Central America, rapidly expanding their domain to an area over 1,000 kilometers of the coast. Blood genetic analyses reveal that the St. Vincent Black Caribs' gene pool contains the highest proportion of Amerindian genes “approximately 50%”, while the coastal communities exhibit a more African ancestry “up to 80%”. This apparent discrepancy can be explained in one of three ways: “1” the original Black Caribs of St. Vincent had a higher proportion of Amerindian genes. However, gene flow and incorporation of African populations residing along the coast into the Black Carib gene pool resulted in more African coastal groups; “2” those Black Caribs displaying African phenotypes were selectively deported; “3” that natural selection, in a malarial environment, operated in favor of those individuals with the more African phenotypes and resistance to Plasmodium falciparum.  相似文献   

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