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With increasing urbanization, urban‐fragmented landscapes are becoming more and more prevalent worldwide. Such fragmentation may lead to small, isolated populations that face great threats from genetic factors that affect even avian species with high dispersal propensities. Yet few studies have investigated the population genetics of species living within urban‐fragmented landscapes in the Old World tropics, in spite of the high levels of deforestation and fragmentation within this region. We investigated the evolutionary history and population genetics of the olive‐winged bulbul (Pycnonotus plumosus) in Singapore, a highly urbanized island which retains <5% of its original forest cover in fragments. Combining our own collected and sequenced samples with those from the literature, we conducted phylogenetic and population genetic analyses. We revealed high genetic diversity, evidence for population expansion, and potential presence of pronounced gene flow across the population in Singapore. This suggests increased chances of long‐term persistence for the olive‐winged bulbul and the ecosystem services it provides within this landscape. 相似文献
994.
Milk is an important source of energy and nutrients, especially for children, and in Kenya, milk consumption is higher than other countries in the region. One major concern with milk is the risks of chemical contaminants, and reports of high levels of aflatoxin M1 (AFM1) in milk in Kenya has been causing public health concerns. This study collected marketed milk products every month during 1 year, just as a consumer would purchase them from retailers and traders in a low-income area, and a major supermarket in a middle/high-income area. In total, 291 sampled milk products (raw, pasteurised, UHT milk, yoghurt and lala) were collected and analysed for AFM1 using a commercial ELISA kit. More than 50% of the samples exceeded 50 ng/kg (the level allowed in the EU), but only three samples exceeded 500 ng/kg (the level allowed in the USA). Geometric mean AFM1 level was 61.9 ng/kg in the 135 samples from the low-income area while it was 36.1 ng/kg in the 156 from the higher income area (p?<?0.001). The levels varied significantly depending on the time of year, with lowest levels of milk in January. There were also differences between manufacturers and products, with UHT milk having lower levels. There was no difference depending on the price for all dairy products, but when only including milk, higher price was associated with lower levels of AFM1. In conclusion, this study shows that milk purchased by a consumer is likely to contain AFM1 above 50 ng/kg, and that further research is needed to find ways to mitigate AFM1 contamination through working with farmers and milk processors both in the formal and informal sectors. 相似文献
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Grace Gredys Harris 《American anthropologist》1989,91(3):599-612
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Saskia van der Kam Stephanie Roll Todd Swarthout Grace Edyegu-Otelu Akiko Matsumoto Francis Xavier Kasujja Cristian Casademont Leslie Shanks Nuria Salse-Ubach 《PLoS medicine》2016,13(2)
Background
Globally, Médecins Sans Frontières (MSF) treats more than 300,000 severely malnourished children annually. Malnutrition is not only caused by lack of food but also by illnesses and by poor infant and child feeding practices. Breaking the vicious cycle of illness and malnutrition by providing ill children with nutritional supplementation is a potentially powerful strategy for preventing malnutrition that has not been adequately investigated. Therefore, MSF investigated whether incidence of malnutrition among ill children <5 y old could be reduced by providing a fortified food product or micronutrients during their 2-wk convalescence period. Two trials, one in Nigeria and one in Uganda, were conducted; here, we report on the trial that took place in Kaabong, a poor agropastoral region of Karamoja, in east Uganda. While the region of Karamoja shows an acute malnutrition rate between 8.4% and 11.5% of which 2% to 3% severe malnutrition, more than half (58%) of the population in the district of Kaabong is considered food insecure.Methods and Findings
We investigated the effect of two types of nutritional supplementation on the incidence of malnutrition in ill children presenting at outpatient clinics during March 2011 to April 2012 in Kaabong, Karamoja region, Uganda, a resource-poor region where malnutrition is a chronic problem for its seminomadic population. A three-armed, partially-blinded, randomised controlled trial was conducted in children diagnosed with malaria, diarrhoea, or lower respiratory tract infection. Non-malnourished children aged 6 to 59 mo were randomised to one of three arms: one sachet/d of ready-to-use therapeutic food (RUTF), two sachets/d of micronutrient powder (MNP), or no supplement (control) for 14 d for each illness over 6 mo. The primary outcome was the incidence of first negative nutritional outcome (NNO) during the 6 mo follow-up. NNO was a study-specific measure used to indicate progression to moderate or severe acute malnutrition; it was defined as weight-for-height z-score <−2, mid-upper arm circumference (MUAC) <115 mm, or oedema, whichever came first.Of the 2,202 randomised participants, 51.2% were girls, and the mean age was 25.2 (±13.8) mo; 148 (6.7%) participants were lost to follow-up, 9 (0.4%) died, and 14 (0.6%) were admitted to hospital. The incidence rates of NNO (first event/year) for the RUTF, MNP, and control groups were 0.143 (95% confidence interval [CI], 0.107–0.191), 0.185 (0.141–0.239), and 0.213 (0.167–0.272), respectively. The incidence rate ratio was 0.67 (95% CI, 0.46–0.98; p = 0.037) for RUTF versus control; a reduction of 33.3%. The incidence rate ratio was 0.86 (0.61–1.23; p = 0.413) for MNP versus control and 0.77 for RUTF versus MNP (95% CI 0.52–1.15; p = 0.200). The average numbers of study illnesses for the RUTF, MNP, and control groups were 2.3 (95% CI, 2.2–2.4), 2.1 (2.0–2.3), and 2.3 (2.2–2.5). The proportions of children who died in the RUTF, MNP, and control groups were 0%, 0.8%, and 0.4%.The findings apply to ill but not malnourished children and cannot be generalised to a general population including children who are not necessarily ill or who are already malnourished.Conclusions
A 2-wk nutrition supplementation programme with RUTF as part of routine primary medical care to non-malnourished children with malaria, LRTI, or diarrhoea proved effective in preventing malnutrition in eastern Uganda. The low incidence of malnutrition in this population may warrant a more targeted intervention to improve cost effectiveness.Trial Registration
clinicaltrials.gov NCT01497236相似文献999.
Nathan Kapata Pascalina Chanda-Kapata William Ngosa Mine Metitiri Eveline Klinkenberg Nico Kalisvaart Veronica Sunkutu Aaron Shibemba Chishala Chabala Gershom Chongwe Mathias Tembo Lutinala Mulenga Grace Mbulo Patrick Katemangwe Sandra Sakala Elizabeth Chizema-Kawesha Felix Masiye George Sinyangwe Ikushi Onozaki Peter Mwaba Davy Chikamata Alimuddin Zumla Martin P. Grobusch 《PloS one》2016,11(1)
Background
Tuberculosis in Zambia is a major public health problem, however the country does not have reliable baseline data on the TB prevalence for impact measurement; therefore it was among the priority countries identified by the World Health Organization to conduct a national TB prevalence surveyObjective
To estimate the prevalence of tuberculosis among the adult Zambian population aged 15 years and above, in 2013–2014.Methods
A cross-sectional population-based survey was conducted in 66 clusters across all the 10 provinces of Zambia. Eligible participants aged 15 years and above were screened for TB symptoms, had a chest x-ray (CXR) performed and were offered an HIV test. Participants with TB symptoms and/or CXR abnormality underwent an in-depth interview and submitted one spot- and one morning sputum sample for smear microscopy and liquid culture. Digital data collection methods were used throughout the process.Results
Of the 98,458 individuals who were enumerated, 54,830 (55.7%) were eligible to participate, and 46,099 (84.1%) participated. Of those who participated, 45,633/46,099 (99%) were screened by both symptom assessment and chest x-ray, while 466/46,099 (1.01%) were screened by interview only. 6,708 (14.6%) were eligible to submit sputum and 6,154/6,708 (91.7%) of them submitted at least one specimen for examination. MTB cases identified were 265/6,123 (4.3%). The estimated national adult prevalence of smear, culture and bacteriologically confirmed TB was 319/100,000 (232-406/100,000); 568/100,000 (440-697/100,000); and 638/100,000 (502-774/100,000) population, respectively. The risk of having TB was five times higher in the HIV positive than HIV negative individuals. The TB prevalence for all forms was estimated to be 455 /100,000 population for all age groups.Conclusion
The prevalence of tuberculosis in Zambia was higher than previously estimated. Innovative approaches are required to accelerate the control of TB. 相似文献1000.
To quantify individual isoforms of canine myocardial MM creatine kinase (CK) we developed an immunoblot procedure suitable for analysis of large numbers of samples. Isoforms in plasma were separated by agarose electrophoresis, immobilized on nitrocellulose, detected with anti-MM followed by a labeled second antibody, and quantified by well counting. The amount of non-CK protein was reduced with sequential ethanol precipitation. Reproducibility of the assay developed was high with a standard deviation of 5.9% of mean values for each isoform. Variation of results after serial dilutions of samples constituted with 33.3% of each of the three isoforms was modest with a standard deviation of 3.5%. The method developed provided sensitive, discrete resolution of individual MM CK isoforms under nondenaturing conditions and should prove useful for improved, objective definition of the time of onset of irreversible injury to myocardial tissue rendered ischemic and hence improved stratification of patients studied in clinical trials concerned with protection and salvage of myocardium. 相似文献