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681.
This study evaluated the sources of fecal contamination in different river catchments, using a combination of microbial source tracking tools, for human, ruminant, ovine and bovine livestock, in order to define appropriate water management strategies. Every source of waterway pollution was evaluated in river water samples from one urban river catchment and two important farming regions in New Zealand. Fecal pollution was initially measured by testing Escherichia coli and evaluating the presence of human- and ruminant-associated DNA markers of Bacteroidales (BiAdo, BacHum-UCD, BacH, and BacR) and human and ruminant fecal sterols/stanols ratios. Then specific fecal pollution sources were assessed with previously reported quantitative PCR assays targeting human-, bovine-, and ovine-specific viruses: human adenoviruses (HAdV), human JC polyomaviruses, bovine polyomaviruses (BPyV), and ovine polyomaviruses (OPyV). High level of ruminant fecal contamination was detected all over the farming areas, whereas no ruminant sources were identified in the urban river sampling sites. BacR was the most frequently observed ruminant marker and OPyV and BPyV allowed the identification of ovine and bovine fecal sources. The human fecal viral marker (HAdV) was the most frequently observed human marker, highly abundant in the urban sites, and also present in farming areas. This is the first study using simultaneously the ovine and the bovine viral markers to identify and quantify both bovine and ovine fecal pollution.  相似文献   
682.
Industrialization has brought with it environmental problems and the consequences of pollution, which has been affecting the world for decades. Immediate action is required to raise industry's awareness of its social responsibilities toward the environment. However, experience shows that companies that have obtained International Organization of Standardization (ISO) 14001:2015 certifications in Malaysia occupy but a small niche among the country's businesses. The purpose of this study is to assess the list of barriers and challenges to implementing and obtaining certifications under the ISO 14001:2015 Environmental Management System (EMS) by Malaysian firms. In addition, this study will rank these factors relative to their importance. This study is aimed at EMS experts at the Scientific and Industrial Research Institute of Malaysia (SIRIM QAS International Sdn. Bhd.). The study uses mathematical pairwise comparisons to generate the list of critical challenges and barriers. Therefore, the study is expected to raise environmental awareness among Malaysia's industries regarding the adoption of ISO 14001:2015 standards. Furthermore, the study provides a guideline for Malaysia's industries and policy‐makers to provide them with a better understanding of the barriers and challenges that companies face in implementing ISO 14001:2015 EMS, and at the same time, help them understand the need to eliminate the difficulties of standard implementation.  相似文献   
683.
It is challenging and expensive to monitor and test decentralized composting toilet systems, yet critical to prevent the mismanagement of potentially harmful and pathogenic end-product. Recent studies indicate that mixed latrine composting toilets can be inhibited by high ammonia content, a product of urea hydrolysis. Urine-diverting vermicomposting toilets are better able to accomplish the goals of remote site human waste management by facilitating the consumption of fecal matter by earthworms, which are highly sensitive to ammonia. The reliability of Solvita® compost stability and maturity tests were evaluated as a means of determining feedstock suitability for vermicomposting (ammonia) and end-product stability/completeness (carbon dioxide). A significant linear regression between Solvita® ammonia and free ammonia gas was found. Solvita® ranking of maturity did not correspond to ranking assigned by ammonium:nitrate standards. Solvita® ammonia values 4 and 5 contained ammonia levels below earthworm toxicity limits in 80% and 100% of samples respectively indicative of their use in evaluating feedstock suitability for vermicomposting. Solvita® stability tests did not correlate with carbon dioxide evolution tests nor ranking of stability by the same test, presumably due to in situ inhibition of decomposition and microbial respiration by ammonia which were reported by the Solvita® CO2 test as having high stability values.  相似文献   
684.
Mytilus edulis and M. trossulus are key species in marine intertidal communities that develop a leukemia-like haemic neoplasia at increased incidences at some polluted sites. The tumor-suppressor p53, known to be involved in this disease, was proposed as a biomarker based on sequence polymorphisms in M. trossulus. In this study, p53 mRNA sequence variations in normal and diseased M. edulis were compared with those reported previously for M. trossulus for caged individuals of both species submerged in Burrard Inlet (49°20′16.57″N 123°13′51.37″) in 2007 and 2010. Thirty-seven single nucleotide polymorphisms (SNPs) were detected in M. edulis p53 that formed high linkage disequilibrium blocks associated with late-stage leukemia (p < 0.05). These were found at loci that were more homologous with M. trossulus than with healthy M. edulis p53-predicted haplotypes. Increased susceptibility to this cancer might be due to, in part, p53 alleles containing these SNPs.  相似文献   
685.
686.
Bioconcentration of p-nonylphenol (NP) by fathead minnows was determined under laboratory conditions. Fish were exposed continuously for 42 days to 0.33, 0.93 and 2.36 μgNP/l in a flow-through system. NP was Soxhlet extracted from whole fish homogenates with dichloromethane (DCM). The resulting extract was concentrated and bulk lipids removed by gel permeation and silica-gel chromatography. Compounds were identified and quantified by reverse-phase high-pressure liquid chromatography (RP-HPLC) with fluorescence detection. Mass spectrometry was used for verification of peak assignments. Bioconcentration factors (BCFs) ranged from 245 to 380.  相似文献   
687.
A short scale for measuring safety climate   总被引:3,自引:0,他引:3  
A 6-item measure that assesses global work safety climate was validated using multiple samples each from a hospital and a nuclear energy population. Across all 14 samples the 6-item measure had acceptable internal consistency. The measure was associated with better adherence to safe work practices, reduced exposure to environmental stressors, the presence of more safety policies and procedures, a positive general organizational climate, and decreased accidents. As evidence for discriminant validity, safety climate was unrelated to most demographic measures and had relatively small relationships with sleeping problems and negative mood. Evidence suggests that this measure is a reliable and valid way to assess global safety climate.  相似文献   
688.
A sustained decline in parental consent rates for perinatal autopsies has driven the development of less-invasive methods for death investigation. A wide variety of imaging modalities have been developed for this purpose and include post-mortem whole body magnetic resonance imaging (MRI), ultrasound, computed tomography (CT) and micro-focus CT techniques. These are also vital for “minimally invasive” methods, which include potential for tissue sampling, such as image guidance for targeted biopsies and laparoscopic-assisted techniques. In this article, we address the range of imaging techniques currently in clinical practice and those under development. Significant advances in high-field MRI and micro-focus CT imaging show particular promise for smaller and earlier gestation foetuses. We also review how MRI biomarkers such as diffusion-weighted imaging and organ volumetric analysis may aid diagnosis and image interpretation in the absence of autopsy data. Three-dimensional printing and augmented reality may help make imaging findings more accessible to parents, colleagues and trainees.  相似文献   
689.
Watercraft collisions account for 25–30% of manatee deaths annually in Florida. Education and outreach interventions for boaters are strategies for reducing manatee mortality. We evaluated the effectiveness of the Manatee Watch program by surveying primary boat users whose boats were approached by Manatee Watch. We compared the attitudes, knowledge, and behavioral intentions of boaters who received Manatee Watch materials with a control group of boaters observed by the Florida Marine Research Institute in Tampa Bay during 1999–2001. Results of the 51-item telephone survey with 499 boaters indicated that the Manatee Watch intervention had little effect on boater’s attitudes, knowledge, and behaviors regarding manatees. However, individual attitude scores were positively correlated with safe boating behaviors in shallow waters including maintaining a slower speed and watching out for manatees. Overall knowledge about manatees was correlated with one manatee-safe boating behavior. To improve efficacy, educators should (a) incorporate evaluation into the planning stages of program development; (b) target messages to influence boaters’ attitudes toward manatees and ecosystem health, and their feelings of ownership and empowerment; (c) facilitate active participation of the boaters; and (d) increase the duration and variety of intervention.  相似文献   
690.
Visitors’ perceptions of impacts and acceptable standards for environmental conditions can provide essential information for the sustainable management of tourist destinations, especially protected areas. To this end, visitor surveys were administered during the peak visitor season in Cape Range National Park, on the northwest coast of Western Australia and adjacent to the iconic Ningaloo Reef. The central focus was visitors’ perceptions regarding environmental conditions and standards for potential indicators. Conditions considered of greatest importance in determining visitors’ quality of experience included litter, inadequate disposal of human waste, presence of wildlife, levels of noise, and access to beach and ocean. Standards were determined, based on visitors’ perceptions, for a range of site-specific and non-site-specific indicators, with standards for facilities (e.g., acceptable number of parking bays, signs) and for negative environmental impacts (e.g., levels of littering, erosion) sought. The proposed standards varied significantly between sites for the facilities indicators; however, there was no significant difference between sites for environmental impacts. For the facilities, the standards proposed by visitors were closely related to the existing situation, suggesting that they were satisfied with the status quo. These results are considered in the context of current research interest in the efficacy of visitor-derived standards as a basis for protected area management.  相似文献   
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