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Habitat loss and degradation threaten forest specialist wildlife species, but some generalist mesopredators exploit disturbed areas and human‐derived food, which brings them into closer contact with humans. Mesopredator release is also important for human health for known zoonotic disease reservoirs, such as Asian civets (Viverridae family), since this group includes the intermediator species for the SARS‐CoV‐1 outbreak. Here we use camera trapping to evaluate the habitat associations of the widespread banded civet (Hemigalus derbyanus) across its range in Southeast Asia. At the regional scale, banded civet detections among published studies were positively associated with forest cover and negatively associated with human population. At the local scale (within a landscape), hierarchical modeling of new camera trapping showed that abundance was negatively associated with forest loss and positively associated with distance to rivers. These results do not support mesopredator release and suggest a low likelihood overlap with humans in degraded habitats and, therefore, a low risk of zoonotic disease transmission from this species in the wild. We also estimate that banded civet distribution has contracted to under 21% of its currently recognized IUCN Red List range, only 12% of which falls within protected areas, and a precipitous recent decline in population size. Accordingly, we suggest the banded civet''s Red List status should be re‐evaluated in light of our findings.  相似文献   
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Carbon monoxide (CO) exposure at high concentrations results in overt neurotoxicity. Exposure to low CO concentrations occurs commonly yet is usually sub-clinical. Infants are uniquely vulnerable to a variety of toxins, however, the effects of postnatal sub-clinical CO exposure on the developing brain are unknown. Apoptosis occurs normally within the brain during development and is critical for synaptogenesis. Here we demonstrate that brief, postnatal sub-clinical CO exposure inhibits developmental neuroapoptosis resulting in impaired learning, memory, and social behavior. Three hour exposure to 5 ppm or 100 ppm CO impaired cytochrome c release, caspase-3 activation, and apoptosis in neocortex and hippocampus of 10 day old CD-1 mice. CO increased NeuN protein, neuronal numbers, and resulted in megalencephaly. CO-exposed mice demonstrated impaired memory and learning and reduced socialization following exposure. Thus, CO-mediated inhibition of neuroapoptosis might represent an important etiology of acquired neurocognitive impairment and behavioral disorders in children.  相似文献   
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For centuries, spices have been utilized as flavourants, colourants and as preservatives in food. Moreover, spices possess various antimicrobial properties with massive health benefits for the treatment and management of ailments and diseases. The present study was focused on three (3) aspects; (1) isolation and molecular identification of bacteria from the meat; (2) to determine the antimicrobial activity of the spices against the pathogens; (3) to assess the organoleptic properties of the spiced meat. A total of twelve (n = 12) spices evaluated against forty (n = 40) spoilage food-borne pathogenic bacteria (Escherichia coli and Enterococci spp.). The spice extracts were tested using disk diffusion method to determine the inhibition abilities. The results show that clove and black seed cumin extract exhibited excellent antibacterial activity against most pathogenic bacteria. Clove displayed the highest inhibition zone of 18 mm against E. coli (EcFwS1). Clove extract was the most inhibitor followed by black cumin, whereas extracts of thyme and cinnamon showed weak antibacterial activities against the tested strains. The most sensitive strain to spice extracts was Enterococcus spp. (EnFmL1) and the most resistant strain being E. coli. (EcFmS1 and EcFpL1). Untreated meat showed that E. coli and Enterococcus spp. count was 4.4 * 105 ± 3.4 * 105 and 2.2 * 105 ± 3.6 * 104 cfu/mL respectively after 7 days while the single dose of clove showed 5.4 * 104 ± 4.4 * 102 cfu/mL of E. coli and 1.7 * 105 ± 4.1 * 104 cfu/mL of Enterococcus spp. The organoleptic characteristics such as colour, texture, odour, pH, shape of the single dose of clove on the meat was overall acceptable.  相似文献   
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ABSTRACT

Entrepreneurship is often touted as an economic opportunity that embodies American ideals of individualism and financial gain. Yet social scientists have long noted divergent entrepreneurial outcomes among various groups. In this paper, we consider how race informs entrepreneurship for minority business owners. In particular, we focus on the ways black entrepreneurs use racial counterframes as a means of defining various aspects of the entrepreneurial experience. Furthermore, we introduce the concept of intersectional counterframes to show how black entrepreneurs understand business ownership as a response to categories that interact with not only to race, but other social group categories as well, such as gender. We argue here that these business owners use both counterframes to construct entrepreneurship not simply as a potential pathway to economic stability, but perhaps more importantly, as a response to existing inequality.  相似文献   
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Untangling the causes of native species loss in human-modified systems is difficult and often controversial. Evaluating the impact of non-native species in these systems is particularly challenging, as additional human perturbations often precede or accompany introductions. One example is the ongoing debate over whether mammal declines within Everglades National Park (ENP) were caused by either the establishment of non-native Burmese pythons (Python molurus bivittatus) or the effects of other anthropogenic stressors. We examined the influence of both pythons and a host of alternative stressors—altered hydrology and habitat characteristics, mercury contamination and development—on the distribution of the marsh rabbit (Sylvilagus palustris), a once common mammal in ENP. Distance from the epicenter of the python invasion best explained marsh rabbit occurrence in suitable habitat patches, whereas none of the alternative stressors considered could explain marsh rabbit distribution. Estimates of the probability of marsh rabbit occurrence ranged from 0 at the python invasion epicenter to nearly 1.0 150 km from the invasion epicenter. These results support the hypothesis that invasive pythons shape the distribution of marsh rabbits in southern Florida. The loss of marsh rabbits and similar species will likely alter trophic interactions and ecosystem function within the Everglades, an internationally important hotspot of biodiversity. Further, our results suggest that non-native species can have profound impacts on mainland biodiversity.  相似文献   
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To address the ongoing debate over the impact of invasive species on native terrestrial wildlife, we conducted a large-scale experiment to test the hypothesis that invasive Burmese pythons (Python molurus bivittatus) were a cause of the precipitous decline of mammals in Everglades National Park (ENP). Evidence linking pythons to mammal declines has been indirect and there are reasons to question whether pythons, or any predator, could have caused the precipitous declines seen across a range of mammalian functional groups. Experimentally manipulating marsh rabbits, we found that pythons accounted for 77% of rabbit mortalities within 11 months of their translocation to ENP and that python predation appeared to preclude the persistence of rabbit populations in ENP. On control sites, outside of the park, no rabbits were killed by pythons and 71% of attributable marsh rabbit mortalities were classified as mammal predations. Burmese pythons pose a serious threat to the faunal communities and ecological functioning of the Greater Everglades Ecosystem, which will probably spread as python populations expand their range.  相似文献   
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Plants contain the genes for both formamidopyrimidine-DNA glycosylase (FPG) and oxoguanine glycosylase (OGG). These enzymes play analogous roles in the base excision repair pathways of bacteria (FPG) and archaea, yeast, and mammals (OGG). Why have plants retained both genes? We tested one hypothesis by comparing the specificities of Arabidopsis FPG and OGG purified from Escherichia coli expression clones. Using depurinated DNA as substrate, the specific activity of Arabidopsis FPG was higher than that of Arabidopsis OGG. Using DNA oxidized by treatment with light in the presence of methylene blue, the specific activities of Arabidopsis FPG and OGG were equal. Using an oligonucleotide containing one oxoguanine (paired with C) and labeled with fluorescein, the specific activity of Arabidopsis OGG was greater than that of either FPG. The results support the hypothesis that genes for the two enzymes have been retained during evolution of plants for their specialized enzyme activities.  相似文献   
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