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1.
A field study was conducted to investigate spinal kinematics and loading in the nursing profession using objective and subjective measurements of selected nursing tasks observed in a hospital setting. Spinal loading was estimated using trunk motion dynamics measured by the lumbar motion monitor (LMM) and lower back compressive and shear forces were estimated using the three-dimensional (3D) Static Strength Prediction Program. Subjective measures included the rate of perceived physical effort and the perceived risk of low back pain. A multiple logistic regression model, reported in the literature for predicting low back injury based on defined risk groups, was tested. The study results concluded that the major risk factors for low back injury in nurses were the weight of patients handled, trunk moment, and trunk axial rotation. The activities that required long time exposure to awkward postures were perceived by nurses as a high physical effort. This study also concluded that self-reported perceived exertion could be used as a tool to identify nursing activities with a high risk of low-back injury.  相似文献   
2.
We continue to study the implications of IR Cohen's work on immune cognition for vaccine strategies when simple elicitation of sterilizing immunity fails, using a mathematical model derived from the large deviations programme of applied probability. Our work makes explicit the linkage between an individual's 'immunocultural condensation' and embedding social or historical structures and processes, in particular power relations between groups. We use methods adapted from the theory of ecosystem resilience to explore the consequences of the sudden 'perturbation' caused by infection, in the context of such embedding. The methodology open pathways in the design of vaccine strategy which are closed by simplistic genetic or cross-sectional 'inequality' analyses that — in effect — either reify 'race' or deny the persisting burdens of racism.  相似文献   
3.
The effect of oxytetracycline-medicated feeds on antibiotic resistance in gram-negative bacteria from fish intestines and water in catfish ponds was investigated. In experiments in the fall and spring, using ponds with no previous history of antibiotic usage, percentages of tetracycline-resistant bacteria in catfish intestines obtained from medicated ponds increased significantly after 10 days of treatment. In the fall, resistance of the intestinal and aquatic bacteria returned to pretreatment levels within 21 days after treatment. In the spring, resistance declined after treatment but remained higher than pretreatment levels for at least 21 days in intestinal bacteria and for 5 months in aquatic bacteria. Plesiomonas shigelloides, Aeromonas hydrophila, and Citrobacter freundii were isolated frequently in both spring and fall; Escherichia coli, Klebsiella pneumoniae, Edwardsiella tarda, and Enterobacter spp. were isolated primarily in the spring. Oxytetracycline treatment did not affect the distribution of bacterial species in the fall but may have accelerated a shift toward greater prevalence of members of the family Enterobacteriaceae in the spring. Multiple antibiotic resistance did not appear to be elicited by oxytetracycline treatment.  相似文献   
4.
BACKGROUND & AIMS: The role of the cytokine interleukin 2 (IL-2) has long been recognized as central to normal immunologic function and defense against infection after burns and trauma, but little effort has been directed towards its role in acute pancreatitis (AP), which also has a high mortality related to sepsis. This study investigated the potential role of IL-2 in mice with diet-induced AP. METHODS: AP was induced in mice by 10 days of feeding a choline-deficient, ethionine-supplemented diet. T-helper (CD4) cells were estimated, and T-cell mitogen-stimulated splenocyte proliferation and IL-2 production in vitro were measured on days 3, 7, and 10. RESULTS: Significant reduction in IL-2 production was found on day 3 (32%; P < 0.05) and day 10 (48%; P < 0.005). Administration of intraperitoneal lipopolysaccharide on day 10 was associated with reduced IL-2 production (P < 0.025) 4 hours later and 90% mortality in animals with AP. In vivo therapy with recombinant IL-2 improved in vitro IL-2 secretion (P < 0.05) and reduced lipopolysaccharide-induced mortality (P = 0.036). CONCLUSIONS: Murine diet-induced AP is associated with impaired immune function and increased susceptibility to sepsis and may be a valuable tool in the investigation of immunomodulation in AP.  相似文献   
5.
Unlike other lakes in tropical regions, Lake Naivasha exhibits low fish species diversity. The fishery is based on introduced fish species that are not native to the lake. The lake ecosystem is very fragile, as reflected in its fluctuating fish catches. The fishery almost completely collapsed in 2001, due partly to mismanagement and ignorance about needed conservation measures. The Kenyan government, like many governments around the world, recognized the need to involve fishers and other stakeholders, in order to ensure better management of the lake fisheries resources. Also referred to as collaborative management (co-management), this management approach provides the opportunity to share responsibility for managing the fishery resources between the government and the community. A total ban on fishing was imposed in February 2001, lasting for 1 year, to allow lake fish stocks to recover. This study analyses the co-management process for Lake Naivasha, and discusses the role played by the community during the fishing ban, as well as the successes and challenges encountered, and the tribulations and perceptions of the fishers regarding the new management strategy. It also comprises the first documentation of community participation in fisheries management begun for Lake Naivasha in the year 2001.  相似文献   
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7.
'Racial' disparities among cancers, particularly of the breast and prostate, are something of a mystery. For the US, in the face of slavery and its sequelae, centuries of interbreeding has greatly leavened genetic differences between Blacks and Whites, but marked contrasts in disease prevalence and progression persist. Adjustment for socioeconomic status and lifestyle, while statistically accounting for much of the variance in breast cancer, only begs the question of ultimate causality. Here we propose a more basic biological explanation that extends the theory of immune cognition to include an elaborate tumor control mechanism constituting the principal selection pressure acting on pathologically mutating cell clones. The interplay between them occurs in the context of an embedding, highly structured, system of culturally-specific psychosocial stress. A rate distortion argument finds that larger system able to literally write an image of itself onto the disease process, in terms of enhanced risk behaviour, accelerated mutation rate, and depressed mutation control. The dynamics are analogous to punctuated equilibrium in simple evolutionary systems, accounting for the staged nature of disease progression. We conclude that 'social exposures' are, for human populations, far more than incidental cofactors in cancer etiology. Rather, they are part of the basic biology of the disorder. The aphorism that culture is as much a part of human biology as the enamel on our teeth appears literally true at a fundamental cellular level.  相似文献   
8.
The linking of control theory and information theory via the Data Rate Theorem and its generalisations allows for construction of necessary conditions statistical models of body mass regulation in the context of interaction with a complex dynamic environment. By focusing on the stress-related induction of central obesity via failure of HPA axis regulation, we explore implications for strategies of prevention and treatment. It rapidly becomes evident that individual-centred biomedical reductionism is an inadequate paradigm. Without mitigation of HPA axis or related dysfunctions arising from social pathologies of power imbalance, economic insecurity, and so on, it is unlikely that permanent changes in visceral obesity for individuals can be maintained without constant therapeutic effort, an expensive – and likely unsustainable – public policy.  相似文献   
9.
Monitoring of aquatic pollution is important for ascertaining the relationship between fisheries and the general ecosystem health of a lake. This study evaluated the use of changes in pollution indicators in Lake Victoria, Kenya, as a decision support tool for fisheries management and productivity. Principal component analysis (PCA; R2 ≥ 0.5, P < 0.05) of physical and chemical parameters delineated sampling sites into ecological cluster zones consisting of the inner gulf (C1), mid‐gulf (C2) and open lake (C3). Test results for lead (Pb) and mercury (Hg) levels in the Nile perch tissues were found to be compliant with EU standards. The inner and mid‐gulfs of the Winam Gulf had high levels of total (1818.8 ± 102–1937.78 ± 94 cfu 100 mL?1) and faecal (390 ± 21 cfu 100 mL?1) coliforms attributable to urban sewage and industrial effluents exceeded WHO standards. Similarly, Winam Gulf was more polluted than the open lake, with higher total phosphorus and nitrogen concentrations, turbidity levels and electrical conductivity. Low phytoplankton biovolume and a low number of macroinvertebrates genera, and high zooplankton densities and pollution‐tolerant catfishes (e.g., Schilbe victoriae; Clarias gariepinus) were observed in Winam Gulf. Faecal coliforms and dissolved oxygen influenced the abundance of tolerant fish species (e.g., S. victoriae) in the lake. This study indicated a declining trend of ecological integrity in the Winam Gulf, compared with the open waters of Lake Victoria. An integrated management approach directed to minimizing pollution levels, especially in the Winam Gulf, is recommended to enhance fishery production.  相似文献   
10.
The atmospheric concentration of methane (CH4) exerts a strong influence on the global climate. Notably, wetlands are important CH4 sources, whose emission represents an ecosystem process depending on such wetland characteristics as organic matter, temperature, pH, methanogenesis and CH4 oxidation, all of which vary on the basis of the type of wetland. Methane fluxes were investigated in a preliminary study in the region, using the chamber method in the open water and macrophyte‐infested wetlands of swampy and riverine types in Kilifi, a coastal district in Kenya, Africa. Despite a lack of significant interactions, the macrophyte‐infested areas emitted the highest quantity of methane of about 21.96 ± 0.04 mg CH4 m?2 day?1, compared with the water areas that emitted about 19.35 ± 0.05 mg CH4 m?2 day?1. The preliminary CH4 fluxes measured in this study are below the range reported from previous wetland field experiments in the tropics and temperate regions, indicating the need to conduct a series of similar experiments to produce more precise total estimates in the entire region.  相似文献   
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