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571.
Debate exists as to what the more appropriate prediction is regarding the effects of multiple stigmatized group memberships on employment discrimination. The ethnic prominence (EP), multiple minority status (MMS), and subordinate male target hypotheses were assessed for the combined effects of ethnic group membership (Arabic), sex, social status, and job type on hiring evaluations. Two correspondence tests in the field (Study 1) and two experimental studies in the lab (Study 2) and in the field (Study 3) were conducted. Studies 1 and 2 showed evidence for the EP hypothesis when low‐status jobs were tested. The odds for rejection were four times higher for Arab than for Dutch applicants. Applicants' sex, socio‐economic status, and external client contact did not moderate findings (Study 1). The effect of applicants' ethnic group membership was further moderated by raters' motivation to control prejudice (Study 2). Study 3 showed evidence for the MMS hypothesis. We found double jeopardy against Arab women who applied for high‐status jobs when recruiters' prejudice was controlled. Study findings show that discrimination in resume screening may depend upon the particular intersection of applicant, job, and recruiter characteristics. We discussed implications for anonymous resume screening and research on evaluation of applicants possessing multiple stigmatizing characteristics. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
572.
Environmental and Ecological Statistics - Recently there has been some renewed interest in skew-normal distribution (SND) because it provides a nice and natural generalization (in terms of...  相似文献   
573.
Heavy metals can act as co-selecting agents and promote antibiotic resistance. Most frequent resistances to heavy metals are observed for zinc and cadmium. P. aeruginosa and E. coli are commonly resistant to heavy metals and antibiotics. Heavy metals proliferate antibiotic resistance through co- and cross-resistance. Heavy metal and antibiotic resistances are common near anthropogenic activities. Antibiotic resistance in human pathogens can proliferate under selective pressures. Heavy metals in environmental reservoirs may contribute to selecting antibiotic-resistant strains. To determine the associations between heavy metals and antibiotic resistance, a literature review was conducted to systematically collect and categorize evidence for co-occurrence of resistance to heavy metals and antibiotics within human pathogenic bacteria in water, wastewater, and soil. In total, 42 publications adhered to inclusion criteria. Across the reservoirs, zinc and cadmium were the most commonly observed heavy metals associated with resistance to antibiotics. Pseudomonas aeruginosa and Escherichia coli were the most commonly studied bacteria with reported co-occurrence of resistance to several heavy metals and antibiotic classes. As co-selecting agents, prevalence of heavy metals in the environment can proliferate resistance to heavy metals and antibiotics through co-resistance and cross-resistance mechanisms. In comparing different reservoirs, soils and sediments harbor higher heavy metal and antibiotic resistances compared to water environments. Additionally, abiotic factors such as pH can affect the solubility and hence, the availability of heavy metals to bacterial pathogens. Overall, our review demonstrates heavy metals act as co-selecting agents in the proliferation of antibiotic resistance in human pathogens in multiple environmental reservoirs. More studies that include statistical data are needed to further describe the exposure-response relationships between heavy metals and antibiotic resistance in different environmental media. Moreover, integration of culture-based and molecular-based methods in future studies are recommended to better inform our understanding of bacterial co- and cross-resistance mechanisms to heavy metals and antibiotics.  相似文献   
574.
ABSTRACT

Conservation of protected areas requires understanding of the consumption of forest products by rural people who live near protected forests. Socioeconomic factors such as a better education, income, land holding size, have been used to understand the patterns of consumption of non-timber forest products (NTFPs). Ethnicity, and especially whether or not people are indigenous to the forested areas, may also change consumption patterns. In this study we analysed the socioeconomic factors, indigeneity and geographical locations of people living in the buffer zones of Vietnam’s Bu Gia Map National Park to better understand the key determinants of the consumption of NTFPs. We conducted 121 interviews with local households and found that indigeneity, education, family size, and the area of land used were statistically significant in explaining the amount of NTFPs consumed, while indigeneity and area of land used by local people had positive relationships with the diversity (measured in number of categories) of NTFPs consumed by local people. Interestingly, there were statistically significant effects of interactions between the area of land used and indigeneity on the consumption of NTFPs. The amount of these products is important for indigenous people who belong to the groups using small and medium areas of land. The medium land use group consumed significantly fewer categories of NTFPs than the small and large land use groups. This data may help local managers to develop interventions that support biodiversity conservation, promote sustainability of these important resources and improve the social welfare of marginal groups.  相似文献   
575.
Coastal erosion results in loss of land, which impacts the economy, coastal residents and settlement plans, especially in the context of rising sea levels caused by climate change. Studying soil particle-size fractions in mangrove forests will help provide a better understanding of the relationship between soil proportions and coastal processes as well as the role of mangrove forests to support coastal planning and management. Soil samples were collected at 26 sampling plots at depths of 10 cm and 40 cm in the Cu Lao Dung (CLD), Long Phu (LP) and Vinh Chau (VC) mangrove forests in Viet Nam’s Soc Trang Province. The soil proportions based on six different particle-sizes (<0.074 mm, 0.074–0.1 mm, 0.1–0.25 mm, 0.25–0.5 mm, 0.5–1.0 mm, and >1.0 mm) were measured using a dry sieving method. Analysis showed that soil particle-sizes ranging between 0.074 and 0.5 mm made up 75–95 % of the soil sample weight at both depths. The high standard deviation values of soil proportions of each given particle-size among sampling plots indicated the soil proportions by particle-size varied widely across the sampling plots. Cluster analysis found similar pattern of soil particle-size proportions for samples collected in CLD and VC, and different pattern of soil particle-size proportions in samples collected at LP, which is more impacted by the Mekong River flow and has a thin mangrove forest belt.?Non-metric dimension scaling (NMDS) analysis showed that sampling plots across the landward sites of the three mangrove forest areas were distributed in the nearby locations (Stress?=?0.11). This indicated that soil proportions of particle-sizes of samples collected from areas of the natural forest composed of different species were more similar. Such similarities were not found, however, in samples collected from middle and seaward plots dominated by single-species plantations.  相似文献   
576.
Human exposure to polychlorinated dibenzodioxins (PCDD) and dibenzofurans (PCDF), especially 2,3,7,8 tetrachlorodibenzo-p-dioxin (TCDD), was investigated in Vietnam since initial severe adverse health effects were reported in the late 1970s. The purpose of this study was to determine the effects of dioxin exposure on steroid hormones of primiparae in an Agent Orange/dioxin hot-spot and a non-exposed area in Vietnam. Sixteen primiparae (8 at each site), all of whom were aged between 20 and 30 years with infants aged between 4 and 16 weeks, agreed to participate in this study. The mean dioxin levels in breast milk of primiparae from the hot-spot area, in terms of PCDD, PCDF, and PCDD?+?PCDF toxic equivalents (TEQ), were significantly higher than those for the non-exposed area. PCDD TEQ, PCDF TEQ, and PCDD?+?PCDF TEQ levels showed a significant correlation with dehydroepiandrosterone (DHEA), androstenedione (A-dione), and estradiol (E2) in the saliva of primiparae in a combination of hot-spot and non-exposed areas in Vietnam. The dose–response curve between salivary E2 or A-dione levels and dioxin levels was U-shaped in humans. This study provides an overview of studies regarding dioxin hot-spots and effects on human health and steroid hormone levels in particular, with a focus on the toxicity attributed to dioxins and furans. Furthermore, causal evidence regarding the effects of dioxins on endocrine disruption in humans is provided.  相似文献   
577.
The activities of extracellular enzymes are important in understanding decomposition of soil organic matter in wetlands subjecting to drying. The activity of soil extracellular enzymes (β-glucosidase, N-acetylglucosaminidase, and phosphatase), and related physicochemical parameters were monitored in constructed freshwater wetlands during a one-month drying manipulation. Drying increased redox potential and decreased soil water content significantly (P<0.05). Higher content of soil organic matter (P<0.05) and higher concentrations of inorganic N (nitrate, P<0.01; and ammonia, P<0.001) were also observed significantly under drying condition. Soil hydrolase enzyme activities were stimulated significantly (β-glucosidase, P<0.05; N-acetylglucosaminidase, P<0.01; and phosphatase, P<0.001), and a two-phase pattern of enzyme activities was revealed under drying condition. The increase of soil enzyme activities under drying condition was significantly related to soil redox potential (P<0.001). Drying strongly affected soil enzyme activities only when soil water content remained above an optimal level for enzymatic catalysis (higher than 23% w/w), corresponding to redox potentials below 250–300 mV. Our results suggest that, under drying condition, potential enzyme activities may be regulated by redox potential, in respect to soil moisture, and consequently alter nutrient availability in wetlands.  相似文献   
578.
This study investigated the effect of nutrient concentration and litter cover on the development of quantitative shoot parameters and belowground biomass (BGB) production of Zizania latifolia. Zizania latifolia is a common emergent aquatic species in East Asia. Four treatments were done at the study site, and were observed between May 2003 and December 2005. The treatments are namely, high nutrient (HN) with litter cover (HNWL), high nutrient without litter cover (HNNL), low nutrient (LN) with litter cover (LNWL), and low nutrient without litter cover (LNNL). The quantitative shoot parameters and BGB had higher values for treatments with high nutrient (HN) compared to the low nutrient treatments (LN), independent of the presence of litter cover. Furthermore, the life span of the secondary shoots was also higher in HN treatments compared to LN treatments. The BGB productivity was higher in the HNNL treatment compared to the other treatments. The LNWL treatment showed the least developed quantitative shoot parameters, e.g. plant height, and the lowest BGB for Z. latifolia. It was generally observed that the combined effects of low nutrients and litter cover negatively affected shoot development and BGB production.  相似文献   
579.
Since 1986, when green oysters occurred due to the copper and organic pollution in the Charting coastal area, the government banned all maricultural activity. It has been claimed that growing algae in a polluted environment may clean the water of pollutants and restore the marine ecosystem. to test this hypothesis, in the Charting coastal area a three-year programme (from August 1992 to July 1995) was carried out. the survey programme included environmental components such as salinity, temperature, pH, dissolved oxygen, biological oxygen demand (BOD), particulate organic carbon (POC), heavy metals and ecological indicators such as nutrients, chlorophyll-a, primary productivity. in the first year study, the environmental background data collected was used to select the suitable season and locations for growing large algae transferred from the laboratory to the field study area. Since September 1993, various species of large algae have been cultured. Although some of the growing algae were damaged by a typhoon in August 1994, the impact of the growing algae on the environmental conditions in the area has been monitored throughout. Elsewhere, we have reported that in the algae growing area higher dissolved oxygen with lower values of BOD and POC were found, and the concentrations of heavy metals in both water and sediments decreased. the purpose of this paper is to evaluate the possible impact of growing large algae on the ecological conditions in Charting coastal waters through the period from August 1983 to May 1995. As a result of the positive results obtained, large amounts of algae have again been cultured in the same area during the period from April 29 to May 25, 1995. We expect that inorganic and organic pollutants will be reduced by the algal growth, oyster mariculture will be restored and finally, the fishery resources potential will be increased.  相似文献   
580.
N‐acetyltransferase (NAT) activity was determined in 100 fish (Oreochromis mossambicus) livers using 2‐aminofluorene and p‐aminobenzoic acid as substrates. Overall, the liver NAT activity of the 50 females was higher than the liver NAT activity of the 50 males. The activities (mean ± SD) of NAT from kidney, blood, intestine, and liver of males was 0.42 ± 0.11, 0.12 ± 0.03, 0.12 ± 0.08, and 1.56 ± 0.54 nmol/min/mg protein for the acetylation of 2‐aminofluorene and 0.36 ± 0.09, 0.09 ± 0.01, 0.11 ± 0.04, and 0.46 ± 0.15 nmol/min/mg protein for the acetylation of p‐aminobenzoic acid. In kidney, blood, intestine, and liver from female fish, the activities obtained were 1.60 ± 0.12, 0.35 ± 0.07, 0.15 ± 0.09, and 1.89 ± 0.50 nmol/min/mg protein for 2‐aminofluorene and 0.95 ± 0.11, 0.27 ± 0.03, 0.13 ± 0.09, and 0.57 ± 0.12nmol/min/mg protein for p‐aminobenzoic acid. Kinetic constants for arylamine N‐acetyltransferase activity in kidney, blood, intestine, and liver from fish with rapid, intermediate, and slow acetylator activity were determined. Apparent K m and V max values for 2‐aminofluorene were 5.5 and 7‐fold higher for liver than for the other tissues. Apparent K m and V max values for p‐aminobenzoic acid were 3.5 and 4.7‐fold higher for liver than for the other tissues. Based on the 2‐aminofluorene NAT activity of liver, there appears to be a polymorphism in NAT activity with 16 rapid, 28 intermediate, and 56 slow acetylators among the 100 fish assayed. This is the first demonstration of acetyl CoA: arylamine N‐acetyltransferase activity in fresh water fish and could lead to the development of a fish model for monitoring the effect of pollution of water environments on native species.  相似文献   
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