首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
The American Indian and Alaskan Native population has grown rapidly since 1950 because of changes in the racial classification of persons with mixed Indian and non‐Indian descent. These changes have challenged once common expectations that the Indian population was likely to shrink over time through assimilation. However, in regions of the United States where the recent growth of the Indian population has been particularly sharp most married Indians are married to non‐Indians. Fertility rates of women who are part of intermarried couples are lower than fertility rates for Indian women in racially endogamous marriages. The majority of the children of intermarried Indians in high intermarriage regions are labelled with the race of the non‐Indian parent. Intermarriage is likely to substantially reduce the long‐run impact of changes in identification on the future growth of the Indian population. At the same time, in a few states the American Indian population remains ethnically homogenous and shows no signs of imminent amalgamation into the general American population.  相似文献   

2.
The northeast Indian passageway connecting the Indian subcontinent to East/Southeast Asia is thought to have been a major corridor for human migrations. Because it is also an important linguistic contact zone, it is predicted that northeast India has witnessed extensive population interactions, thus, leading to high genetic diversity within groups and heterogeneity among groups. To test this prediction, we analyzed 14 biallelic and five short tandem-repeat Y-chromosome markers and hypervariable region 1 mtDNA sequence variation in 192 northeast Indians. We find that both northeast Indian Y chromosomes and mtDNAs consistently show strikingly high homogeneity among groups and strong affinities to East Asian groups. We detect virtually no Y-chromosome and mtDNA admixture between northeast and other Indian groups. Northeast Indian groups are also characterized by a greatly reduced Y-chromosome diversity, which contrasts with extensive mtDNA diversity. This is best explained by a male founder effect during the colonization of northeast India that is estimated to have occurred within the past 4,000 years. Thus, contrary to the prediction, these results provide strong evidence for a genetic discontinuity between northeast Indian groups and other Indian groups. We, therefore, conclude that the northeast Indian passage way acted as a geographic barrier rather than as a corridor for human migrations between the Indian subcontinent and East/Southeast Asia, at least within the past millennia and possibly for several tens of thousand years, as suggested by the overall distinctiveness of the Indian and East Asian Y chromosome and mtDNA gene pools.  相似文献   

3.
S. E. Evers  C. G. Rand 《CMAJ》1982,126(3):249-252
A cohort study of health status was undertaken to determine the patterns of morbidity in the first year of life for Indian and non-Indian infants living in southern Ontario. The annual incidence of office-reported health problems was 8.0 episodes for the 99 Indians and 4.5 for the 316 non-Indians studied. The risk of illness of most diagnostic categories was more than 1.5 times greater and the rate of hospital admission 4 times greater for the Indian infants. There was no difference between the two cohorts in the rates of visits to hospital emergency departments. The main cause of illness in both cohorts was respiratory tract infection; lower respiratory tract infections, particularly pneumonia, were a major health problem among the Indian infants. Only 36% of the Indian infants compared with 68% of the non-Indian infants attended five or more well-baby examinations. Part of the difference in morbidity between the Indian and non-Indian infants may be attributed to environmental factors, health care behaviour and geographic constraints.  相似文献   

4.
The crude extract and saponins of Indian pseudoginseng and saponins of Korean ginseng have been studied using a battery of biological tests in rats and mice. Indian pseudoginseng saponins were found to exhibit better activity than the Korean ginseng saponins in several tests employed. The results indicate a need for in-depth study of Indian pseudoginseng as an adaptogenic agent, after cultivation of the plant under controlled conditions.  相似文献   

5.
Selenocyanate (SeCN(-)) is a major contaminant in the effluents from some oil refineries, power plants, and in mine drainage water. In this study, we determined the potential of Indian mustard (Brassica juncea) and muskgrass (a macroalga, Chara canescens) for SeCN(-) phytoremediation in upland and wetland situations, respectively. The tolerance of Indian mustard to toxic levels of SeCN(-) was similar to or higher than other toxic forms of Se. Indian mustard treated with 20 microM SeCN(-) removed 30% (w/v) of the Se supplied in 5 d, accumulating 554 and 86 microg of Se g(-1) dry weight in roots and shoots, respectively. Under similar conditions, muskgrass removed approximately 9% (w/v) of the Se supplied as SeCN(-) and accumulated 27 microg of Se g(-1) dry weight. A biochemical pathway for SeCN(-) degradation was proposed for Indian mustard. Indian mustard and muskgrass efficiently degraded SeCN(-) as none of the Se accumulated by either organism remained in this form. Indian mustard accumulated predominantly organic Se, whereas muskgrass contained Se mainly as selenite and organic Se forms. Indian mustard produced volatile Se from SeCN(-) in the form of less toxic dimethylselenide. Se volatilization by Indian mustard accounted for only 0.7% (w/v) of the SeCN(-) removed, likely because the biochemical steps in the production of dimethylselenide from organic Se were rate limiting. Indian mustard is promising for the phytoremediation of SeCN(-) -contaminated soil and water because of its remarkable abilities to phytoextract SeCN(-) and degrade all the accumulated SeCN(-) to other Se forms.  相似文献   

6.
We analysed polymorphism of 13 microsatellites in two Indian domesticated pig types (North Indian and Northeast Indian). Heterozygosity, polymorphism information content, and probability of identity of two random individuals were calculated for all microsatellites in both types. The number of alleles observed at a locus varied between five and 12. The evaluated microsatellites exhibited a very high heterozygosity and polymorphism information content. The probability of identity of two random individuals from different populations taking into account all the 13 microsatellites was as low as 3.51 × 10-19. On the basis of these results, we propose that these microsatellite markers may be used with reliability for studying the genetic diversity and for identification of individuals in Indian pig types.  相似文献   

7.
The origins of the nearly one billion people inhabiting the Indian subcontinent and following the customs of the Hindu caste system are controversial: are they largely derived from Indian local populations (i.e. tribal groups) or from recent immigrants to India? Archaeological and linguistic evidence support the latter hypothesis, whereas recent genetic data seem to favor the former hypothesis. Here, we analyze the most extensive dataset of Indian caste and tribal Y chromosomes to date. We find that caste and tribal groups differ significantly in their haplogroup frequency distributions; caste groups are homogeneous for Y chromosome variation and more closely related to each other and to central Asian groups than to Indian tribal or any other Eurasian groups. We conclude that paternal lineages of Indian caste groups are primarily descended from Indo-European speakers who migrated from central Asia approximately 3,500 years ago. Conversely, paternal lineages of tribal groups are predominantly derived from the original Indian gene pool. We also provide evidence for bidirectional male gene flow between caste and tribal groups. In comparison, caste and tribal groups are homogeneous with respect to mitochondrial DNA variation, which may reflect the sociocultural characteristics of the Indian caste society.  相似文献   

8.
Indian oil sardines, commercially and ecologically important pelagic fishes in Indian waters have not been the focus of major genetic studies as compared to their counter parts in Atlantic and Pacific oceans in spite of several reports suggesting stock complexity and intraspecific diversity. Hence, we investigated the genetic stock structure of Indian oil sardine, Sardinella longiceps using microsatellite markers by collecting a total of 768 individuals from eight locations along the Indian coast and one from Gulf of Oman over a 2 year period (2013–2015). Six polymorphic microsatellite markers revealed significant genetic differentiation between populations with the highest FST value (0.055) between Oman and Indian coastline. Within the Indian coastline another major subdivision between Mumbai & Mangalore vs. other regions was detected (FST value 0.047) which was also confirmed in Barrier analysis with the presence of two strong barriers between these eco-regions. There exist pronounced differences in oceanographic and environmental features between Gulf of Oman, Western Indian Ocean and Eastern Indian Ocean (Bay of Bengal) which may act as barriers for effective dispersal and gene flow resulting in genetic differentiation. Even though, the samples collected from Calicut, Kollam, Trivandrum, Chennai and Vizag showed the presence of admixed genotypes, the possible presence of distinct populations in some regions was evident in Bayesian analysis which needs to be confirmed further using more widespread sampling design and powerful markers. The present study provided insights into the biocomplexity and intra-specific diversity of Indian oil sardine populations, which needs to be preserved for maintaining resilience of these important fishes to climate change and habitat alterations in the Indian Ocean.  相似文献   

9.
This survey represents the first characterization of mitochondrial DNA diversity within three breeds of Indian sheep (two strains of the Deccani breed, as well as the Bannur and Garole breeds) from different geographic regions and with divergent phenotypic characteristics. A 1061-bp fragment of the mitochondrial genome spanning the control region, a portion of the 12S rRNA gene and the complete phenyl tRNA gene, was sequenced from 73 animals and compared with the corresponding published sequence from European and Asian breeds and the European Mouflon (Ovis musimon). Analysis of all 156 sequences revealed 73 haplotypes, 52 of which belonged to the Indian breeds. The three Indian breeds had no haplotypes in common, but one Indian haplotype was shared with European and other Asian breeds. The highest nucleotide and haplotype diversity was observed in the Bannur breed (0.00355 and 0.981 respectively), while the minimum was in the Sangamneri strain of the Deccani breed (0.00167 and 0.882 respectively). All 52 Indian haplotypes belonged to mitochondrial lineage A. Therefore, these Indian sheep are distinct from other Asian and European breeds studied so far. The relationships among the haplotypes showed strong breed structure and almost no introgression among these Indian breeds, consistent with Indian sheep husbandry, which discourages genetic exchange between breeds. These results have implications for the conservation of India's ovine biodiversity and suggest a common origin for the breeds investigated.  相似文献   

10.
This article discusses second-generation Indo-Caribbean (West Indian of Indian descent) teenagers’ ethnic identities, through a look at their taste preferences and self assertions of identity. Both Indo-Caribbean young men and women draw from multiple influences on their identities. In terms of tastes in clothing and movies, however, girls are more interested in things Indian, and in “Indian culture”. Boys, on the other hand, choose to distance themselves from an Indian identity. Three factors explain these gender differences in choices about ethnic identity: (1) different media images for South Asian men and women; (2) a school context lending different levels of peer symbolic status to perceived Indian boys and girls; and (3) a gendered process of migration by which women maintain stronger cultural roots in the new country. The findings in this article point to the need to pay attention to gender differences when considering ethnic incorporation.  相似文献   

11.
This paper re-enters the contested discussion surrounding the Indian Enigma, the high prevalence of chronic undernutrition in India relative to sub-Saharan Africa. Jayachandran & Pande (JP) argue that the key to the Indian Enigma lies in the worse treatment of higher birth order children, particularly girls. Analyzing new data, and taking into account issues relating to robustness to model specification, weighting and existing critiques of JP., we find: (1) Parameter estimates are sensitive to sampling design and model specification; (2) The gap between the heights of pre-school African and Indian children is closing; (3) The gap does not appear to be driven by differential associations by birth order and child sex; (4) The remaining gap is associated with differences in maternal heights. If Indian women had the heights of their African counterparts, pre-school Indian children would be taller than pre-school African children; and (5) Once we account for survey design, sibling size and maternal height, the coefficient associated with being an Indian girl is no longer statistically significant.  相似文献   

12.
The achievement of John Collier, commissioner of Indian Affairs under Franklin Delano Roosevelt and father of the Indian Reorganization Act (IRA), has been increasingly ignored or denigrated by the anthropological profession, upon whose advice Collier relied to reverse the nation's Indian policy and resuscitate the inherent powers of Indian tribes. I assert that but for the IRA, Indian tribal governments would probably not exist today. I also attempt to refute those critics who assert (1) that the U.S. government imposed elective systems on the Indians against their will; (2) that even though Indian voters may have voted to accept the IRA, the vast majority indicated their rejection of the act by not voting at all; (3) that IRA governments are "puppet" governments; and (4) that Indians have lost independence and freedom as a result of the IRA. The tribal structures created or revived by the IRA are now vigorous and growing in power and authority, and I postulate that with the growth among anthropologists of a "resistance model" of Indian. White relations and the gradual repudiation of the assimilationist model held by most anthropologists 50 years ago, Collier's policy of locating tribal autonomy within the federal system of government rather than in resistance to it came to be seen as a "cop-out" by anthropologists who failed to realize that without the policy Indian tribal governments would probably soon have ceased to exist.  相似文献   

13.
The Indian meal moth, Plodia interpunctella (Hübner), and Angoumois grain moth, Sitotroga cerealella (Olivier), are two globally distributed stored-grain pests. Laboratory experiments were conducted to examine the impact that corn (Zea mays L.) kernels (i.e., grain) of some Bacillus thuringiensis Berliner (Bt) corn hybrids containing CrylAb Bt delta-endotoxin have on life history attributes of Indian meal moth and Angoumois grain moth. Stored grain is at risk to damage from Indian meal moth and Angoumois grain moth; therefore, Bt corn may provide a means of protecting this commodity from damage. Thus, the objective of this research was to quantify the effects of transgenic corn seed containing CrylAb delta-endotoxin on Indian meal moth and Angoumois grain moth survival, fecundity, and duration of development. Experiments with Bt grain, non-Bt isolines, and non-Bt grain were conducted in environmental chambers at 27 +/- 1 degrees C and > or = 60% RH in continuous dark. Fifty eggs were placed in ventilated pint jars containing 170 g of cracked or whole corn for the Indian meal moth and Angoumois grain moth, respectively. Emergence and fecundity were observed for 5 wk. Emergence and fecundity of Indian meal moth and emergence of Angoumois grain moth were significantly lower for individuals reared on P33V08 and N6800Bt, MON 810 and Bt-11 transformed hybrids, respectively, than on their non-Bt transformed isolines. Longer developmental times were observed for Indian meal moth reared on P33V08 and N6800Bt than their non-Bt-transformed isolines. These results indicate that MON 810 and Bt-11 CrylAb delta-endotoxin-containing kernels reduce laboratory populations of Indian meal moth and Angoumois grain moth. Thus, storing Bt-transformed grain is a management tactic that warrants bin scale testing and may effectively reduce Indian meal moth and Angoumois grain moth populations in grain without application of synthetic chemicals or pesticides.  相似文献   

14.
Effects of soil factors and seed-dispersing heteromyid rodents on the distribution of Indian ricegrass Achnatherum hymenoides were studied at a sharp ecotone between a sandy area with abundant Indian ricegrass and a rocky area where Indian ricegrass was scarce Two hypotheses were tested 1) Soil factors limited the recruitment rate of Indian ricegrass in the rocky habitat, and 2) Heteromyid rodents limited the distribution of Indian ricegrass because they did not scatterhoard seeds in the rocky habitat Seed-planting experiments and soil analyses showed that soil characteristics, especially texture and salinity, limited the distribution of Indian ricegrass, but also that microsites existed in the rocky habitat that were suitable for germination and growth of Indian ricegrass In particular, as many plants survived over their first winter in the rocky habitat as in the sandy habitat, although surviving plants were taller in the sandy habitat Analysis of the soil seed bank indicated that fewer seeds were dispersed to the rocky habitat than to the sandy habitat To determine whether scatterhoards were being made in the rocky habitat, seeds dyed with fluorescent powder were placed along the ecotone and the fates of these seeds were assessed Twice as many of these seeds were scatterhoarded in the sandy habitat as in the rocky habitat and seeds were cached further from the ecotone in the sandy habitat The results suggest that both soil characteristics and heteromyid rodents influence the distribution of Indian ricegrass in westem Nevada  相似文献   

15.
2003~2004年在印度南部的50家农户进行了4次二化性家蚕品种农村试养,结果表明:供试品种生长发育经过较印度二化性家蚕品种慢,茧丝质优于印度对照种,适应性、抗逆性整体表现较印度对照种弱。由于气候、饲养技术、叶质等的差异,与其在国内的饲养相比,印度饲养试验中供试品种的各项性能指标均偏低,生产能力达不到国内水平。印度南部适宜饲养二化性家蚕的季节为9月至翌年的3月,进入4月后,不宜饲养二化性家蚕品种。  相似文献   

16.
The longitudinal growth of the long bones and growth in breadth of the ilium are assessed for a population of protohistoric Arikara Indians from South Dakota through the correlation of skeletal measurements with estimates of chronological age at death. Comparison of the Arikara growth data with those from other Indian samples (Indian Knoll and Late Woodland, Illinois) reveals similar rates of bone growth, when compensation is made for methodological variation. As predicted from documented variation in adult statures, the Indian samples indicate slower growth rates than those of Whites but faster than those of Eskimos.  相似文献   

17.
Over the last decade there has been increasing scholarly interest in the ethnic character of the Indian state. This interest has coincided with the rise of the Hindu revivalist Bharatiya Janata Party [BJP], nation‐wide clashes between Hindus and Muslims, and bitter conflict over affirmative action for backward classes. Simultaneously, the Indian state has been confronted by regional movements in Kashmir, Assam and Punjab seeking secession from the Indian Union. By focusing on the Punjab crisis this article argues that conventional explanations have concentrated on national political centralization and regional economic factors, to the neglect of Sikh ethno‐nationalism and its dialectical relationship with strategies for ethnic conflict management followed by the Indian state since 1947. Drawing on recent revisionist accounts, the Indian state, it is suggested, should be viewed as a form of an ethnic democracy in which hegemonic control is exercised over non‐Hindu ethnic groups. The Punjab case‐study shows that hegemonic control has characterized the relationship between the Sikhs and the Indian state between 1947 and 1984, and efforts to re‐establish hegemonic control after 1984 degenerated into violent control. The experience of the last ten years suggests that hegemonic control and violent control are unlikely to provide an enduring solution to the Punjab crisis. Rather, there is a need to address fundamentally the crisis of the Indian political system and how it has managed its minorities since 1947. Central to this reassessment is the viability of India's majoritarian political system in the context of an ethnically plural society.  相似文献   

18.
This article focuses on the political struggles between Hindu and Muslim Indian immigrant groups in the United States over the definition of "Indianness". Hindu Indian American organizations define India as a Hindu society and are strong supporters of the Hindu nationalist movement in India. Muslim Indian American organizations, on the other hand, view India as a multi-religious and multicultural society. They are striving to safeguard India's secularism and towards this end, have entered into coalitional relationships with lower caste groups. Both types of organizations are working to influence American and Indian politics in line with their respective interests, leading to an exacerbation of the conflict between the two immigrant groups. This article examines the reasons for this development and its implications, both for the development of an Indian American community in the United States and for religion and politics in India.  相似文献   

19.
We constructed a phylogenetic hypothesis for western Indian Ocean sunbirds (Nectarinia) and used this to investigate the geographic pattern of their diversification among the islands of the Indian Ocean. A total of 1309 bp of mitochondrial sequence data was collected from the island sunbird taxa of the western Indian Ocean region, combined with sequence data from a selection of continental (African and Asian) sunbirds. Topological and branch length information combined with estimated divergence times are used to present hypotheses for the direction and sequence of colonization events in relation to the geological history of the Indian Ocean region. Indian Ocean sunbirds fall into two well-supported clades, consistent with two independent colonizations from Africa within the last 3.9 million years. The first clade contains island populations representing the species Nectarinia notata, while the second includes Nectarinia souimanga, Nectarinia humbloti, Nectarinia dussumieri, and Nectarinia coquereli. With respect to the latter clade, application of Bremer's [Syst. Biol. 41 (1992) 436] ancestral areas method permits us to posit the Comoros archipelago as the point of initial colonization in the Indian Ocean. The subsequent expansion of the souimanga clade across its Indian Ocean range occurred rapidly, with descendants of this early expansion remaining on the Comoros and granitic Seychelles. The data suggest that a more recent expansion from Anjouan in the Comoros group led to the colonization of Madagascar by sunbirds representing the souimanga clade. In concordance with the very young geological age of the Aldabra group, the sunbirds of this archipelago have diverged little from the Madagascar population; this is attributed to colonization of the Aldabra archipelago in recent times, in one or possibly two or more waves originating from Madagascar. The overall pattern of sunbird radiation across Indian Ocean islands indicates that these birds disperse across ocean barriers with relative ease, but that their subsequent evolutionary success probably depends on a variety of factors including prior island occupation by competing species.  相似文献   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号