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81.
Zooplankton carcasses are common within aquatic systems and potentially serve as organic-rich substrates for bacteria. We compared the microbial decomposition of representative crustacean (copepod) and non-crustacean (rotifer) zooplankton carcasses and monitored changes in carcass protein and lipid contents. Our results showed that carcass decomposition was mainly driven by bacteria colonizing from the surrounding water. Carcass-associated bacteria displayed higher protease and lipase activities than free-living bacteria. Protein content of copepod carcasses decreased by 70% within the first 8 h and shifted from larger to smaller sized proteins, while protein loss in rotifer carcasses was insignificant. Carcass lipid content did not change significantly over 24 h in either zooplankton type, although polar branched fatty acids increased on copepod carcasses indicating an increase in viable microbial biomass. Our results suggest differential turnover of protein versus lipid within a zooplankton carcass and that carcasses from different zooplankton groups would affect water column microbial processes differently.  相似文献   
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84.
This paper describes a study that was performed to determine the cost-effective method of dredging in Mobile Bay in the United States and to explore the possibility of utilizing the dredged materials in an environmentally sustainable way. An analysis of the historical cost and working time data for hopper dredging and pipeline dredging for Mobile Bay showed that there was not a substantial difference in unit costs between the two methods. However, while the disposal methods for dredged materials were taken into consideration, the pipeline dredging seemed to be a more desirable and environmentally friendly option for dredging in Mobile Bay. In addition to cost analysis, the paper discusses several possible ways of sustainable management of dredged materials. The paper also indicates that if the sediment in Mobile Bay is found to be contaminated by the Deepwater Horizon oil spill, the pipeline dredging will become a more desirable dredging alternative.  相似文献   
85.
This paper explores the circumstances in which communities may effectively reduce risks. It draws on the example of two ‘Risk and Resilience Committees’ (RRCs) that were established in Nepal as part of an action research project: one in Panchkhal in the central region, operating as a community‐based organisation (CBO); and the other in Dhankuta in the eastern region, embedded in municipal government. In‐depth interviews were conducted with RRC members. Wider community preferences for risk reduction were examined through a questionnaire survey. In Dhankuta, the RRC obtained further funding, developed strong upward and downward institutional links, and applied a ‘disaster risk reduction lens’ to existing local government responsibilities. In Panchkhal, RRC activities have been limited by funding and have focused on the strengthening of livelihoods. It may be concluded tentatively that community‐based disaster risk reduction activities are more successful when they are institutionally embedded in local government structures.  相似文献   
86.
The increasing popularity of local food consumption can be attributed to the heightened awareness of food safety concerns, carbon emissions produced from food transportation, and an understanding of how large corporations’ obtain their food supplies. Although there is increasing discussion on both the local and organic food movement independently, there is not a wide availability of literature examining the motivations and perceptions of consumers with regard to farmers’ markets. Issues such as perceptions about what type of food consumers are purchasing at markets, nor the main motivations for frequenting such establishments are discussed. Therefore the purpose of this study was to determine consumer motivations, benefits, and perceptions of farmers’ markets. Using the case study location of Toronto, Canada, this study surveyed 300 participants during the fall of 2011. Findings indicated that the main purpose for visiting famers’ markets is not solely to fulfill grocery needs. Quality of products offered and the ability to support the local community were the primary motivators to visit the markets.  相似文献   
87.
Objective: Characterization of the severity of injury should account for both mortality and disability. The objective of this study was to develop a disability metric for thoracic injuries in motor vehicle crashes (MVCs) and compare the functional outcomes between the pediatric and adult populations.

Methods: Disability risk (DR) was quantified using Functional Independence Measure (FIM) scores within the National Trauma Data Bank for the most frequently occurring Abbreviated Injury Scale (AIS) 2–5 thoracic injuries. Occupants with thoracic injury were classified as disabled or not disabled based on the FIM scale, and comparisons were made between the following age groups: pediatric, adult, middle-aged, and older occupants (ages 7–18, 19–45, 46–65, and 66+, respectively). For each age group, DR was calculated by dividing the number of patients who were disabled and sustained a given injury by the number of patients who sustained a given injury. To account for the effect of higher severity co-injuries, a maximum AIS adjusted DR (DRMAIS) was also calculated for each injury. DR and DRMAIS could range from 0 to 100% disability risk.

Results: The mean DRMAIS for MVC thoracic injuries was 20% for pediatric occupants, 22% for adults, 29% for middle-aged adults, and 43% for older adults. Older adults possessed higher DRMAIS values for diaphragm laceration/rupture, heart laceration, hemo/pneumothorax, lung contusion/laceration, and rib and sternum fracture compared to the other age groups. The pediatric population possessed a higher DRMAIS value for flail chest compared to the other age groups.

Conclusion: Older adults had significantly greater overall disability than each of the other age groups for thoracic injuries. The developed disability metrics are important in quantifying the significant burden of injuries and loss of quality life years. Such metrics can be used to better characterize severity of injury and further the understanding of age-related differences in injury outcomes, which can influence future age-specific modifications to AIS.  相似文献   

88.
The adoption and enforcement of building codes is considered the most effective tool in safeguarding lives and property against earthquakes. There would appear to be a vital regulatory role for government in the enforcement of building codes, but this is somewhat at odds with the neoliberal agenda of ‘rolling back the state’. This paper explores constraints to the implementation of building codes in the context of changing roles and responsibilities of local authorities in Bihar in India. In-depth interviews were conducted with key stakeholders across major urban centres in north Bihar. Some factors, such as: code complexity; competition between the public and private sectors for qualified personnel; and low public risk perception were found to be less significant in Bihar than has been noted elsewhere, while other factors such as: the cost of earthquake-resistant measures; political interests; corrupt practices; and lack of government capacity were important. Additional factors were also revealed by the research, some of which are exacerbated by the neoliberal climate of urban governance. While the recent 2014 byelaws represent an improvement in the system and a degree of re-regulation, ambiguities create opportunities for failures arising from ‘normalised irresponsibility’.  相似文献   
89.
Several methods were developed to detect the cyclic volatile methylsiloxanes (cVMSs) including octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclohexasiloxane (D6) in water, sediment, soil, biota, and biosolid samples. Analytical techniques employed to optimize measurement of this compound class in various matrices included membrane-assisted solvent extraction in water, liquid–solid extraction for sediment, soil, biota, and biosolid samples. A subsequent analysis of the extract was conducted by large-volume injection–gas chromatography−mass spectrometry (LVI−GC−MS). These methods employed no evaporative techniques to avoid potential losses and contamination of the volatile siloxanes. To compensate for the inability to improve detection limits by concentrating final sample extract volumes we used a LVI–GC–MS. Contamination during analysis was minimized by using a septumless GC configuration to avoid cVMS’s associated with septum bleed. These methods performed well achieving good linearity, low limits of detection, good precision, recovery, and a wide dynamic range. In addition, stability of cVMS in water and sediment was assessed under various storage conditions. D4 and D5 in Type-I (Milli-Q) water stored at 4 °C were stable within 29 d; however, significant depletion of D6 (60–70%) occurred only after 3 d. Whereas cVMS in sewage influent and effluent were stable at 4 °C within 21 d. cVMS in sediment sealed in amber glass jars at −20 °C and in pentane extracts in vials at −15 °C were stable during 1 month under both storage conditions.  相似文献   
90.
The trade in wild meat is an important economic component of rural people's livelihoods, but it has been perceived to be among the main causes of the decline of wildlife species. Recently, the COVID-19 pandemic has brought to light an additional concern of wildlife markets as a major human-health challenge. We analyzed data from the largest longitudinal monitoring (1973–2018) of the most important urban wild-meat markets in Iquitos, Peru, to examine the trends in and impacts of these markets on people's livelihoods. Over the last 45 years, wild meat sales increased at a rate of 6.4 t/year (SD 2.17), paralleling urban population growth. Wild meat sales were highest in 2018 (442 t), contributing US$2.6 million (0.76%) to the regional gross domestic product. Five species of ungulates and rodents accounted for 88.5% of the amount of biomass traded. Vulnerable and Endangered species represented 7.0% and 0.4% of individuals sold, respectively. Despite growth in sales, the contribution of wild meat to overall urban diet was constant: 1–2%/year of total meat consumed. This result was due to greater availability and higher consumption of cheaper meats (e.g., in 2018, poultry was 45.8% cheaper and was the most consumed meat) coupled with the lack of economic incentives to harvest wild meat species in rural areas. Most wild meat was sold salted or smoked, reducing the likelihood of foodborne diseases. Community-based wildlife management plans and the continued trade bans on primates and threatened taxa may avoid biodiversity loss. Considering the recent COVID-19 pandemic, future management plans should include potential viral hosts and regulation and enforcement of hygiene practices in wild-meat markets.  相似文献   
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