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51.
Cadmium usually hampers plant growth, but bacterial inoculation may improve stress tolerance in plants to Cd by involving various mechanisms. The objective was to characterize and identify bacteria that improve plant growth under Cd stress and reduce Cd uptake. Cadmium-tolerant bacteria were isolated from rhizosphere soil, which was irrigated with tannery effluent, and six strains were selected as highly tolerant to Cd, showing minimum inhibitory concentration as 500 mg L?1 or 4.45 mmol L?1. These strains were identified by 16S rRNA gene analysis and functional analysis in regard to plant growth promotion characteristics. To determine their effect on cereal growth under Cd stress, seeds were inoculated with these strains individually and grown in soil contaminated with three Cd levels (0, 40 and 80 mg kg?1). Biomass production, relative water content (RWC), electrolyte leakage (ELL) and tissue Cd concentration were measured. Biomass of both cereals was inhibited strongly when exposed to Cd; however, bacterial inoculation significantly reduced the suppressive effect of Cd on cereal growth and physiology. The bacterial isolates belonged to the genera Klebsiella, Stenotrophomonas, Bacillus and Serratia. Maize was more sensitive than wheat to Cd. Klebsiella sp. strain CIK-502 had the most pronounced effects in promoting maize and wheat growth and lowering Cd uptake under Cd stress.  相似文献   
52.
Concentrations of nine heavy metals (As, Cd, Cu, Fe, Hg, Pb, Mn, Mo and Zn) were determined in the hepatic and renal tissues of 80 stranded California sea lions (Zalophus californianus). Significant age-dependant increases were observed in liver and kidney concentrations of cadmium and mercury, and renal zinc concentrations. Hepatic iron concentrations were significantly higher in females than males. Animals with suspected domoic acid associated pathological findings had significantly higher concentrations of liver and kidney cadmium; and significantly higher liver mercury concentrations when compared to animals classified with infectious disease or traumatic mortality. Significantly higher hepatic burdens of molybdenum and zinc were found in animals that died from infectious diseases. This is the largest study of tissue heavy metal concentrations in California sea lions to date. These data demonstrate how passive monitoring of stranded animals can provide insight into environmental impacts on marine mammals.  相似文献   
53.
The study reports the results of a follow-up evaluation, conducted in 1994, of the impact of a training program for female unskilled metal workers that was implemented at the end of the 1970s. The program was designed to promote occupational skills development, and was first evaluated in 1979. On both occasions of evaluation the investment in training was examined from two perspectives, those of the training participants and management. Data were collected through semistructured personal interviews with key members of personnel management and through a group conversation session with a majority of the original course attendees. Supplementary background information was obtained from documents and records maintained by the organization. At some points, there was a convergence of views on the significance of the training program for occupational skills development, at others a divergence. These convergences and divergences are finally discussed and the findings of the study are related to other research on this particular kind of intervention.  相似文献   
54.
Acute (96 h) and chronic (21 d) exposures of Daphnia magna neonates were carried out with nano- and micro-sized Ag and CeO(2) particles to assess the influence of both material and size of particles on mortality and moulting. Mortality rates for silver in the acute exposures were: AgNP, 56.7 ± 23.3% at 0.1 mg L(-1) and 100 ± 20% at 1 mg L(-1), and micro-Ag, 13.3 ± 6.7% at 0.1 mg L(-1) and 80 ± 20% at 1 mg L(-1). CeO(2) was not acutely toxic at concentrations up to 10 mg L(-1). Mortality for Ag over 21d at concentrations of up to 0.05 mg L(-1) was low, while mortality of 30% was observed for 0.001 mg L(-1) of nano-Ag. CeO(2), with the exception of the 10 mg L(-1) of nano-CeO(2) (100% mortality by day 7), was non-toxic. Inhibition of moulting and growth in the acute study occurred at toxic concentrations (Ag particles), and at 10 mg L(-1) of nano-CeO(2). The chronic study revealed reduced moulting at 0.001 mg L(-1) of nano-Ag and 0.01 and 0.05 mg L(-1) of both sizes of Ag, but there was no impact on D. magna size, and no effects of CeO(2). The toxicity of nano-CeO(2) may be attributed to reduced feeding and physical interference with the daphnids' carapace, resulting in reduced swimming ability. Our results suggest that Ag NPs in particular have the potential to be harmful to aquatic invertebrates after release into the environment, whereas CeO(2) particles appear to cause little adverse effects, and only at environmentally irrelevant concentrations.  相似文献   
55.
Society’s relationship with modern animal farming is an ambivalent one: on the one hand there is rising criticism about modern animal farming; on the other hand people appreciate certain aspects of it, such as increased food safety and low food prices. This ambivalence reflects the two faces of modernity: the negative (exploitation of nature and loss of traditions) and the positive (progress, convenience, and efficiency). This article draws on a national survey carried out in the Netherlands that aimed at gaining a deeper understanding about the acceptance of modern dairy farming in Dutch society. People take two dimensions into account when evaluating different aspects of modern dairy farming: (1) the way living beings are used for production and (2) the way a dairy farm functions as a business. In both these dimensions people appeared to adopt cautious opinions: most people preferred relatively traditional and natural farms and were concerned about the use of nature and treatment of animals in modern production—although this did not imply an outright rejection of modern animal farming. The study also looked for (and sought to explain) differences of opinion between social groups. Besides socio-demographic factors such as age and gender, farming experience and value-orientation (such as socially minded and professional) appeared to be important variables. The values and convictions within modern society can help to explain why some people are greatly concerned about animal welfare while some show less concern. This diversity also helps to explain why general information campaigns are quite ineffective in allaying concerns about modern animal farming.  相似文献   
56.
Mitigation and Adaptation Strategies for Global Change - Public adaptation to climate change affects government budgets directly on the expenditure side, but also indirectly via changes in the tax...  相似文献   
57.
Antimicrobial prophylaxis during surgery aims to prevent post-operative site infections. For fetal surgery, this includes the fetal and amniotic compartments. Both are deep compartments as drug equilibrium with maternal blood is achieved relatively late. Despite prophylaxis, chorio-amnionitis or endometritis following ex utero intrapartum treatment or fetoscopy occur in 4.13% and 1.45% respectively of the interventions. This review summarizes the observations on two commonly administered antimicrobials (cefazolin, clindamycin) for surgical prophylaxis during pregnancy, with emphasis on the deep compartments. For both compounds, antimicrobial exposure is on target when we consider the maternal and fetal plasma compartment. In contrast, amniotic fluid concentrations-time profiles display a delayed and much more blunted pattern, behaving as deep compartment. For cefazolin, there are data that document further dilution in the setting of polyhydramnios. Along this deep compartment concept, there is some accumulation during repeated administration, modeled for cefazolin and observed for clindamycin. The relative underexposure to antimicrobials in amniotic fluid may be reflected in the pattern of maternal-fetal complications after fetal surgery, and suggest that antimicrobial prophylaxis practices for fetal surgery should be reconsidered. Further studies should be designed by a multidisciplinary team (fetal surgeons, clinical pharmacologists and microbiologists) to facilitate efficient evaluation of antimicrobial prophylaxis.  相似文献   
58.
Shifting cultivation around the Calakmul Biosphere Reserve of Mexico, part of the Mesoamerican Biological Corridor, appears to be intensifying temporally through reductions in crop–fallow cycles, with potential impacts on species diversity in the regenerating forest patches surrounding the reserve. This paper documents the temporal intensity of shifting maize cultivation in the region and links it to the species diversity found in secondary vegetation of different ages following different crop–fallow cycles. It finds that younger secondary growth, which is increasing under intensification, has less diversity in species composition. Simultaneously, the concentration of cultivation practices appears to foster more patches in older and more species-diverse vegetation. The implications for the preservation of the region’s forest remain uncertain, however, given the spatial concentration of open lands along two key axes, one which dissects the reserve.  相似文献   
59.
Regional Environmental Change - Due to the growing world population and changing eating habits, there is an increasing demand in sustainable alternative protein sources, whereas the available land...  相似文献   
60.
This study investigates the effects of workers' perceived participation in democratic decision‐making on their prosocial behavioral orientations, democratic values, commitment to the firm, and perceptions of socio‐moral climate. The sample consists of 325 German‐speaking employees from 22 companies in Austria, North Italy, and Southern Germany that vary in their level of organizational democracy (social partnership enterprises, workers' co‐operatives, democratic reform enterprises, and employee‐owned self‐governed firms). The findings suggest that the extent employees participate in democratic forms of organizational decision‐making is positively related to the firm's socio‐moral climate as well as to their own organizational commitment and prosocial and community‐related behavioral orientations. The results also indicate that socio‐moral climate is positively related to employees' organizational commitment. The effect of participation in decision‐making on organizational commitment is partially mediated by socio‐moral climate. Implications for promoting societal and organizational civic virtues among individuals are described. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
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