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1.
Brian P. McEvoy Joanne M. Lind Robert K. Moyzis Sheila M. van Holst Pellekaan Alan N. Wilton 《American journal of human genetics》2010,87(2):297-528
Australia was probably settled soon after modern humans left Africa, but details of this ancient migration are not well understood. Debate centers on whether the Pleistocene Sahul continent (composed of New Guinea, Australia, and Tasmania) was first settled by a single wave followed by regional divergence into Aboriginal Australian and New Guinean populations (common origin) or whether different parts of the continent were initially populated independently. Australia has been the subject of relatively few DNA studies even though understanding regional variation in genomic structure and diversity will be important if disease-association mapping methods are to be successfully evaluated and applied across populations. We report on a genome-wide investigation of Australian Aboriginal SNP diversity in a sample of participants from the Riverine region. The phylogenetic relationship of these Aboriginal Australians to a range of other global populations demonstrates a deep common origin with Papuan New Guineans and Melanesians, with little evidence of substantial later migration until the very recent arrival of European colonists. The study provides valuable and robust insights into an early and important phase of human colonization of the globe. A broader survey of Australia, including diverse geographic sample populations, will be required to fully appreciate the continent''s unique population history and consequent genetic heritage, as well as the importance of both to the understanding of health issues. 相似文献
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3.
Zubair Ahmad 《Ethnic and racial studies》2013,36(3):451-453
The construction of a swimming pool for the European personnel of one of the fifty or so colonial sugar factories still operating in Java in the mid-1930s was a symptom of the growing 'enclavement' of the Dutch colonial communities on the island during the final decades of the Netherlands India. An earlier phase of Dutch colonialism in the Indies had been characterized by hybrid, inclusivist social practices and cultural assumptions generally labelled indisch or Indo-European. By the inter-war decades of the twentieth century, totok – meaning expatriate – norms and values began to assert their hegemony at virtually all levels of colonial society. Yet ambiguity continues to surround this progress from incorporation to differentiation, as instanced by the inter-war history of the Europeans who lived in the residential compound which the pool was designed to service. 相似文献
4.
Tony Mitchell 《Ethnic and racial studies》2013,36(2):278-300
Clara Law's film Floating Life was the first Australian film to be nominated for an Oscar for Best Foreign Film, and the first Australian film to deal with migrant Hong Kong Chinese identities 'from inside'. From perspectives of transnational Chinese migration and flexible citizenship, this article looks at Floating Life as a Hong Kong Chinese migrant reading of Australia, which defamiliarizes and recontextualizes familiar Australian localities and geopolitical formations, contrasting them with the film's other principal loci of Hong Kong and Germany. It also interprets the film as a neo-Confucian study of family disintegration in a migrant context, and an exploration of notions of home and identity. 相似文献
5.
Population migration has played an important role in human evolutionary history and in the patterning of human genetic variation. A deeper and empirically-based understanding of human migration dynamics is needed in order to interpret genetic and archaeological evidence and to accurately reconstruct the prehistoric processes that comprise human evolutionary history. Current empirical estimates of migration include either short time frames (i.e. within one generation) or partial knowledge about migration, such as proportion of migrants or distance of migration. An analysis of migration that includes both proportion of migrants and distance, and direction over multiple generations would better inform prehistoric reconstructions. To evaluate human migration, we use GPS coordinates from the place of residence of the Yemeni individuals sampled in our study, their birthplaces and their parents'' and grandparents'' birthplaces to calculate the proportion of migrants, as well as the distance and direction of migration events between each generation. We test for differences in these values between the generations and identify factors that influence the probability of migration. Our results show that the proportion and distance of migration between females and males is similar within generations. In contrast, the proportion and distance of migration is significantly lower in the grandparents'' generation, most likely reflecting the decreasing effect of technology. Based on our results, we calculate the proportion of migration events (0.102) and mean and median distances of migration (96 km and 26 km) for the grandparent''s generation to represent early times in human evolution. These estimates can serve to set parameter values of demographic models in model-based methods of prehistoric reconstruction, such as approximate Bayesian computation. Our study provides the first empirically-based estimates of human migration over multiple generations in a developing country and these estimates are intended to enable more precise reconstruction of the demographic processes that characterized human evolution. 相似文献
6.
Cancer appears to be inversely associated with both Alzheimer''s and Parkinson''s disease. The relationship between cancer and sporadic motor neuron disease (SMND), however, remains uncertain. Most previous cancer-SMND studies have been undertaken in northern hemisphere populations. We therefore undertook a case-control study to see if a link between cancer and SMND exists in an Australian population. A questionnaire was used to compare past cancer diagnoses in 739 SMND patients and 622 controls, recruited across Australia. Odds ratios with 95% confidence intervals were calculated to look for associations between cancer and SMND. A history of cancer was not associated either positively or negatively with a risk of subsequent SMND. This result remained when age, gender, smoking status, and the four SMND diagnostic subgroups were taken into account. No association was observed between SMND and specific tumours, including melanoma, a common malignancy in Australia. In conclusion, this Australian case-control study does not support an association between a past history of cancer and the development of SMND. This suggests that some pathogenetic mechanisms, such as apoptosis, are less relevant in SMND than in other neurodegenerative diseases where negative associations with cancer have been found. 相似文献
7.
Long distance migration of insects to a subantarctic island 总被引:3,自引:0,他引:3
Penelope Greenslade Roger A. Farrow Jeremy M. B. Smith 《Journal of Biogeography》1999,26(6):1161-1167
Transoceanic migration of four species of macrolepidoptera to subantarctic Macquarie Island has been detected in 7 out of 33 years during the period 1962–96 and is restricted to spring and autumn. Analyses of synoptic charts during the migration period show that autumn immigrants originated from New Zealand and comprised a single species of noctuid moth,Agrotis ipsilon (Walker). Spring immigrants originated from Australia and comprised two noctuids, Dasypodia selenophora Guenée and Persectania ewingii Westwood and a butterfly, Vanessa kershawi (McCoy). Autumn migrations were associated with depressions in the southern Tasman Sea. Spring migrations were associated with the eastward passage of prefrontal airflows ahead of cold fronts which extended from southern Australia to the west of Macquarie Island. In an analysis of one of these events, winds exceeded 30 ms?1 at 300 m altitude and could have transported migrants from Tasmania to Macquarie Island overnight in less than 10 h. Flight activity was assisted by the presence of a nocturnal temperature inversion that maintained upper air temperatures above 5 °C. The effect of potential global warming on the migration and colonization of Macquarie Island by insects is discussed. 相似文献
8.
Michael Sharpe 《Dialectical Anthropology》2005,29(3-4):291-314
For much of its colonial history, the Netherlands experienced little contact with its island possessions in the Caribbean.
Subsequent Dutch policy was formulated in the shadow of the Netherlands primary concern with its prosperous colony of Indonesia.
The 1985 closing of the oil refineries in Aruba and Curacao, Netherlands Antilles and Aruba’s “status aparte” in 1986 triggered
a mass migration from those Dutch “overseas countries” to the Netherlands. These recent migrations of thousands of Dutch post-colonial
citizens have added to the Dutch reevaluation of its colonial past and debates about its multicultural democratic future. 相似文献
9.
J Froom L Culpepper P Grob A Bartelds P Bowers C Bridges-Webb I Grava-Gubins L Green J Lion B Somaini et al. 《BMJ (Clinical research ed.)》1990,300(6724):582-586
STUDY OBJECTIVE--The relation between a history of disorders suggestive of acute otitis media, symptoms, and findings of an examination of the tympanic membrane and doctors'' certainty of diagnosis. Also, to examine differences in prescribing habits for acute otitis media among doctors from different countries. DESIGN--Questionnaires were completed by participating doctors for a maximum of 15 consecutive patients presenting with presumed acute otitis media. SETTING--General practices in Australia, Belgium, Great Britain, Israel, The Netherlands, New Zealand, Canada, Switzerland, and the United States. PATIENTS--3660 Children divided into the three age groups 0-12 months, 13-30 months, and greater than or equal to 31 months. MAIN OUTCOME MEASURES--General practitioners'' responses to questions on their diagnostic certainty and resolution of patients'' symptoms after two months. RESULTS--The diagnostic certainty in patients aged 0-12 months was 58.0%. This increased to 66.0% in those aged 13-30 months and 73.3% in those aged greater than or equal to 31 months. In all age groups diagnostic certainty was positively associated with the finding of a tympanic membrane that was discharging pus or bulging. Redness of the membrane and pain were also associated with certainty in patients aged 13-30 months, and a history of decreased hearing or recent upper respiratory infection was positively associated in patients aged greater than or equal to 31 months. The proportion of patients prescribed antibiotics varied greatly among the countries, from 31.2% in The Netherlands to 98.2% in both Australia and New Zealand, as did the duration of treatment. Patients who did not take antibiotics had a higher rate of recovery than those who did; the rate of recovery did not differ between different types of antibiotic. CONCLUSIONS--Doctors'' certainty of diagnosis of acute otitis media was linked to patient''s age. Improved criteria or techniques for diagnosing acute otitis media, especially in very young children, need to be developed. Antibiotic treatment did not improve the rate of recovery of patients in this study. 相似文献
10.
Kevin C. Grady Thomas E. Kolb Dana H. Ikeda Thomas G. Whitham 《Restoration Ecology》2015,23(6):811-820
Assisted migration of warm‐adapted genotypes to currently cooler climates may reduce maladaptation from future climate change. Few assisted migration trials have considered limitations of the cooler climates and pathogens currently present at transplant sites. This is especially important to consider in riparian ecosystems that are priority targets for restoration in the western United States as they harbor diverse communities. In an effort to validate assisted migration as an effective strategy for mediating the negative impacts of climate change, we used a provenance trial with replicated genotypes from 19 populations of the foundation riparian tree species, Fremont cottonwood (Populus fremontii), transplanted to a cold site to test for genetic variation in growth, mortality, and resistance to shoot blight fungi (Venturia sp.). Populations from cool sites had up to 4 times faster growth, 3 times higher survival, and 8 times higher resistance to Venturia than populations from warm sites, providing evidence of local adaptation to both climate and pathogenic fungi. Budburst phenology and shoot blight were correlated with frost damage, subsequent shrub‐form architecture, and mortality. While climate change models predict 6°C increases, plants transferred distances of 6°C at this time would not perform well; an intermediate transfer distance of less than 3°C would avoid maladaptation to the current environment during assisted migration. Thus, multiple and intermediate transfer phases to supplement local genetic variation will likely be necessary for effective assisted migration to accommodate current environments and large changes in climate. 相似文献
11.
LUKAS KAELIN 《Developing world bioethics》2011,11(1):30-39
The intensified nurse migration leads to severe problems for the health care systems in many developing countries. Using the Philippines as an example, this paper will address the question of global nurse migration from a philosophical perspective. John Rawls' liberal and Michael Walzer's communitarian theory of justice will be examined in view of the ethical problem of nurse migration. In line with Rawls' A Theory of Justice, nurse migration undermines the ability of the people in developing countries to make use of their basic rights and liberties. Walzer's communitarian assessment of nurse migration, on the other hand, will stress the shared ‘thin’ morality, as well as the shared history between the ‘donating’ and receiving countries. This paper argues that the commonality of a shared history and common values implies the moral obligation to ensure a fairer distribution of nurses. 相似文献
12.
Abies religiosa's forests are severely endangered as a result of climate change; to save this species and its biological interactions, population assisted migration is discussed in forest management, but not in the microbial ecology field. Our objectives were to analyze its mycorrhizal networks; and, with this data, to identify potential facilitator plants and it's most important mycorrhizal fungal links. This information could be used together in assisted migration programs to connect Abies religiosa saplings to their mycorrhizal network and improve their field establishment. We collected 47 rhizosphere samples from 19 plant species and sequenced their fungal ITS2 region by Illumina. In the whole fungal community, 464 species were mycorrhizal fungi with assigned guild (32%). In this subset, 85 fungi are arbuscular, 365 ectomycorrhizal and 14 from orchid-mycorriza. The Abies religiosa bipartite network is low nested and highly modular, and has a scale-free architecture. Besides Abies religiosa, the plants with the largest degree and the lowest average shortest path were Salix paradoxa, Muhlenbergia spp., and Baccharis conferta. The most important fungal nodes are species of Cortinarius, Genea, Rhodoscypha, Russula, and Tomentella. We suggest to evaluate the Abies' future establishment in the following scheme: in the first year reintroduce Muhlenbergia spp., and Baccharis conferta, in the second year Salix paradoxa, and in the third year–once the mycorrhizal network is reestablished– Abies religiosa' saplings in close proximity of these plants. This scheme is proposed using the data and network analyses of the present study. 相似文献
13.
Jeffrey Prager 《Ethnic and racial studies》2013,36(1):62-81
This study of undocumented immigrant Nepalese workers in Japan analyses their ethnic history, demographics, migration strategies and work experiences. The majority belong to ethnic groups which the British designated 'martial races', whose tradition of foreign service as 'Gurkha' soldiers in the British and Indian Armies produced a culture of emigration and a remittance economy in rural Nepal. As a result, the present generation has been socialized to be familiar with international migration as an economic option, and has access to networks for its accomplishment. Japan's industrial structure and relative affluence have generated chronic shortages of workers to fill jobs shunned by Japanese in manufacturing and construction industries. This has elevated wages to levels which attract economically distressed foreign migrants such as those from Nepal. Despite the isolation and discrimination which they suffer, these Nepalese find the financial rewards to be sufficient to outweigh the hardships. 相似文献
14.
Rapid evolution is likely to be an important mechanism allowing native species to adapt to changed environmental conditions. Many Northern Hemisphere species have undergone substantial recent changes in phenology and morphology. However, we have little information about how native species in the Southern Hemisphere are responding to climate change. We used herbarium specimens from 21 native alpine plant species in Kosciuszko National Park, Australia, to make over 1,500 measurements of plant size, leaf thickness, leaf mass per area, leaf shape, and leaf size across the last 126 years. Only two out of 21 species (9%) showed significant changes in any of the measured traits. The number of changes we observed was not significantly different to what we would expect by chance alone, based on the number of analyses performed. This lack of change is not attributable to methodology—an earlier study using the same methods found significant changes in 70% of species introduced to southeast Australia. Australia''s native alpine plants do not appear to be adapting to changed conditions, and because of the low elevation of Australia''s mountains, they do not have much scope for uphill migration. Thus, our findings suggest that Australia''s native alpine plants are at even greater risk in the face of future climate change than was previously understood. 相似文献
15.
E M Widdowson M J Dauncey D M Gairdner J H Jonxis M Pelikan-Filipkova 《BMJ (Clinical research ed.)》1975,1(5959):653-655
The fatty acids in the body fat of 41 British and 37 Dutch infants between birth and 1 year were determined. At birth linoleic acid contributed 1-3% of the total fatty acids of the body fat in infants in both countries. By one month its proportion in the fat of the Dutch infants was about 25% and by four months 32-37%; in the fat of the British infants it was never more than 3%. In the Dutch infants this large increase in the linoleic acid percentage was accompanied by a fall in the percentage contribution of others, particularly the saturated acids myristic, palmitic, and stearic. Infants born preterm showed changes in their fat after birth similar to those in fullterm infants. The difference between the composition of the fat of the infants in the two countries is attributed to the nature of the fat in the milk they received. Until recently most British infants who are not breast-fed have been given milks based on cow''s milk with only minor modifications. For the past 10 years many Dutch infants have been given a milk in which all the cow''s milk fat has been replaced by maize oil. Dutch infants also had a lower concentration of cholesterol in their serum than British infants, which was not unexpected. The results show that the triglycerides in the adipose tissue are profoundly influenced by the nature of the fat in the diet. 相似文献
16.
Cell migration is a fundamental feature of the interaction of cells with their surrounding. The cell''s stiffness and ability to deform itself are two major characteristics that rule migration behavior especially in three-dimensional tissue. We simulate this situation making use of a micro-fabricated migration chip to test the active invasive behavior of pancreatic cancer cells (Panc-1) into narrow channels. At a channel width of 7 µm cell migration through the channels was significantly impeded due to size exclusion. A striking increase in cell invasiveness was observed once the cells were treated with the bioactive lipid sphingosylphosphorylcholine (SPC) that leads to a reorganization of the cell''s keratin network, an enhancement of the cell''s deformability, and also an increase in the cell''s migration speed on flat surfaces. The migration speed of the highly deformed cells inside the channels was three times higher than of cells on flat substrates but was not affected upon SPC treatment. Cells inside the channels migrated predominantly by smooth sliding while maintaining constant cell length. In contrast, cells on adhesion mediating narrow lines moved in a stepwise way, characterized by fluctuations in cell length. Taken together, with our migration chip we demonstrate that the dimensionality of the environment strongly affects the migration phenotype and we suggest that the spatial cytoskeletal keratin organization correlates with the tumor cell''s invasive potential. 相似文献
17.
Tests for the production of migration inhibitory factor by peripheral blood leukocytes in response to ubiquitous bacterial and fungal antigens were carried out in patients with untreated Graves'' disease and in healthy control subjects. Dose-response studies, tests for the production of this factor after 72 hours'' stimulation with phytohemagglutinin as a test for reserve, and tests before and after 24 hours'' preculture to deplete suppressor cells were also performed in some patients. The antigens used were Candida, Trichophyton-Oidiomyces-Epidermophyton, mumps live attenuated virus and purified protein derivative of tuberculin. The production of migration inhibitory factor was measured by the agarose microdroplet method.The production of migration inhibitory factor in response to all the antigens except mumps virus was slightly greater in the patients than in the control subjects, although the differences were not significant. The dose-response characteristics and the production of migration inhibitory factor after stimulation with phytohemagglutinin were similar in the two groups. The production of migration inhibitory factor in response to suboptimal concentrations of Candida, Trichophyton-Oidiomyces-Epidermophyton and mumps virus was not enhanced in either group after 24 hours'' preculture apart from a slight increase in response to mumps virus in the patients.These results fail to support the suggestion that patients with Graves'' disease have a deficiency of suppressor cells. 相似文献
18.
Charlotte Laarman 《Ethnic and racial studies》2013,36(7):1232-1250
Abstract In 1949, the Dutch East Indies became independent Indonesia. In the aftermath of decolonization more than 300,000 people migrated from this former colony to the Netherlands. This article focuses on political and public debates in the Netherlands in which the boundaries between former colonizer and colonized were redrawn as a consequence of decolonization and migration. Migrants from former colonies claimed and were attributed a different position in the societies of their former colonizer than other migrants, based on their juridical citizenship, perceived shared history, Dutchness, loyalty and debt. Not all migrants for the former Dutch East Indies could be recipients of the same label. Dutchness could be stretched, but at one point the rhetoric changed from ‘family’ to ‘guests’. 相似文献
19.
Clickers might own a bright future in China if properly introduced although they have not been widely acknowledged as an effective tool to facilitate English learning and teaching in Chinese contexts. By randomly selecting participants from undergraduates in a university in China over four academic years, this study aims to identify the impact of clickers on college English listening and speaking skills, and differences in cognitive loads between clickers and traditional multimedia assisted instruction modes. It was concluded that in China''s college English class, compared with multimedia assisted instruction, (1) clickers could improve college English listening skills; (2) clickers could improve college English speaking skills; and (3) clickers could reduce undergraduates'' cognitive loads in College English Class. Reasons for the results and defects in this study were also explored and discussed, based on learning, teaching and cognitive load theories. Some Suggestions for future research were also raised. 相似文献
20.
Hyperparasites in the form of cytoplasmic RNA elements have been proposed as a biological control agent for Dutch elm disease. We characterized the range of outcomes likely to follow the introduction of such an agent by modelling the resultant population dynamics as an ecological interaction between the wild, ''target'', fungus and the hyperparasitized ''control'' fungus. We used data from the 1970s epidemic of Dutch elm disease in the UK to parameterize the population dynamics of the target fungus, and considered the success of control across a wide range of possibilities for the lethality and transmissibility of the modified control fungus. We decomposed hyperparasite transmissibility into horizontal transmissibility (the ability to colonize previously unparasitized target fungal hosts) and vertical transmissibility (the ability of control fungus to establish new colonies). There is an invasion threshold for both horizontal and vertical transmissibility. As vertical transmission is further increased, there is another threshold at which the target fungus is eradicated because of competitive exclusion by the control fungus. In contrast, eradication by raising horizontal transmission may never succeed because the target fungus needs to be present to support new cases through this route. Between these two thresholds for invasion and exclusion, control and target fungus may coexist. Using a stochastic, spatially extended model, we showed that predictions of success based on high competitive ability of the control fungus (i.e. high vertical transmission) are likely to be more robust than those based on the high degree to which the control fungus can cause target fungus to be hyperparasitized (i.e. high horizontal transmission). 相似文献