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61.
In April-May 2004, the World Health Organization (WHO) implemented, with local authorities, United Nations (UN) agencies and non-governmental organisations (NGOs), an early warning system (EWS) in Darfur, West Sudan, for internally displaced persons (IDPs). The number of consultations and deaths per week for 12 health events is recorded for two age groups (less than five years and five years and above). Thresholds are used to detect potential outbreaks. Ten weeks after the introduction of the system, NGOs were covering 54 camps, and 924,281 people (IDPs and the host population). Of these 54 camps, 41 (76%) were reporting regularly under the EWS. Between 22 May and 30 July, 179,795 consultations were reported: 18.7% for acute respiratory infections; 15% for malaria; 8.4% for bloody diarrhoea; and 1% for severe acute malnutrition. The EWS is useful for detecting outbreaks and monitoring the number of consultations required to trigger actions, but not for estimating mortality.  相似文献   
62.
Occupational low back pain (LBP) remains a leading safety and health challenge. This cross-sectional investigation measured the prevalence of LBP in residential carpenters and investigated ergonomic risk factors. Ninety-four carpenters were investigated for LBP presence and associated risk factors. Ten representative job-tasks were evaluated using the Ovako Working Posture Analysis System (OWAS) and ErgoMaster? 2D software to measure elements of posture, stress, and risk. Job-tasks were found to differ significantly for total lumbar compression and shear at peak loading (p < .001), ranging from 2 956 to 8 606 N and 802 to 1 974 N respectively. OWAS indicated that slight risk for injury was found in 10 job-tasks while distinct risk was found in 7 of the 10 job-tasks. Seven of the 10 job-tasks exceeded the National Institute for Occupational Safety and Health (NIOSH) action limit of 3 400 N for low back loading. The point prevalence for LBP was 14% while the annual prevalence was 38%.  相似文献   
63.
Contemporary studies on sustainability indicator systems (SISs) typically focus on the technical advancement of indicator construction, on qualitative impacts of indicator programmes and on impacts on governance, decision-making and sustainability as a social construct. Yet, their implementation so far has rarely been addressed, even though monitoring and the use of indicator results fall far behind the number of SISs developed. This study aims at the identification of requirements for the development of and constraints to the implementation of SISs in five Asian cities of developing countries. Interviews with local key actors are held, and a qualitative content analysis is carried out. Findings include evidence on the degree of indicator implementation in the case study cities, a hexagonal model for the classification of requirements and constraints, as well as general conclusions for barriers to the use of SISs.  相似文献   
64.
In developing countries, high levels of particle pollution from the use of coal and biomass fuels for household cooking and heating are a major cause of ill health and premature mortality. The cost and complexity of existing monitoring equipment, combined with the need to sample many locations, make routine quantification of household particle pollution levels difficult. Recent advances in technology, however, have enabled the development of a small, portable, data-logging particle monitor modified from commercial smoke alarm technology that can meet the needs of surveys in the developing world at reasonable cost. Laboratory comparisons of a prototype particle monitor developed at the University of California at Berkeley (UCB) with gravimetric filters, a tapered element oscillating microbalance, and a TSI DustTrak to quantify the UCB particle monitor response as a function of both concentration and particle size and to examine sensor response in relation to changes in temperature, relative humidity, and elevation are presented here. UCB particle monitors showed good linearity in response to different concentrations of laboratory-generated oleic acid aerosols with a coarse (mass median diameter, 2.1 microm) and fine (mass median diameter, 0.27-0.42 microm) size distributions (average r2 = 0.997 +/- 0.005). The photoelectric and ionization chamber showed a wide range of responses based on particle size and, thus, require calibration with the aerosol of interest. The ionization chamber was five times more sensitive to fine rather than coarse particles, whereas the photoelectric chamber was five times more sensitive to coarse than fine. The ratio of the response between the two sensors has the potential for mass calibration of individual data points based on estimated parameters of the size distribution. The results demonstrate the significant potential of this monitor, which will facilitate the evaluation of interventions (improved fuels, stoves, and ventilation) on indoor air pollution levels and research on the impacts of indoor particle levels on health in developing countries.  相似文献   
65.
The availability of cadmium (Cd) and zinc (Zn) to sunflower (Helianthus annuus) was investigated in rhamnolipid- and ethylenediaminetetraacetic acid (EDTA)-buffered solutions in order to evaluate the influence of aqueous speciation of the metals on their uptake by the plant, in relation to predictions of uptake by the free ion activity model (FIAM). Free metal ion activity was estimated using the chemical equilibrium program MINTEQ or measured by Donnan dialysis. The uptake of Cd followed the FIAM for the EDTA-buffered solution at EDTA concentrations below 0.4 μM; for the rhamnolipid-buffered solution, the uptake of both metals in roots was not markedly affected by increasing rhamnolipid concentrations in solution. This suggests rhamnolipid enhanced metal accumulation in plant roots (per unit free metal in solution) possibly through formation and uptake of lipophilic complexes. The addition of normal Ca concentrations (low millimetre range) to the rhamnolipid uptake solutions reduced Cd accumulation in shoots by inhibiting Cd translocation, whereas it significantly increased Zn accumulation in shoots. This study confirms that although rhamnolipid could enhance accumulation of Cd in plants roots at low Ca supply, it is not suitable for Cd phytoextraction in contaminated soil environments where Ca concentrations in soil solution are orders of magnitude greater than those of Cd.  相似文献   
66.
Abstract: Fecal coliform (FC) bacteria in coastal waters impair the use of these waters for shellfish harvesting and recreation. This study was designed to quantify and compare FC levels and export in two coastal watersheds with different land uses. Continuous monitoring of rainfall and discharge at three sites in the Jumping Run Creek watershed and one site in the Pettiford Creek watershed were conducted during a 4.5‐year period. Primary land use in the drainage area of one of the three Jumping Run Creek sites is low density industrial, while the other two are residential. Land use in the Pettiford Creek watershed is managed national forest. Nonstorm or base‐flow grab and flow‐proportional storm‐event samples were collected and analyzed for turbidity, conductivity, suspended sediment, nitrogen, phosphorus, and FC. Geometric mean FC levels for the Jumping Run Creek monitoring sites ranged from 593 to 2,096 mpn/100 ml, while the mean level at the Pettiford Creek site was 191 mpn/100 ml. Levels of most other parameters were greater in storm discharge from the Jumping Run Creek sites as compared to Pettiford Creek indicating that pollutant export from a watershed increases with development. Statistical analysis of the monitoring data suggested that FC levels in stormwater samples consistently increased with storm rainfall, but were not consistently correlated with any other parameter, including total suspended solids. Multivariate analysis indicated that the weekly FC export for each of the four sites was lowest during the December‐February quarter. Export was highest during the spring and summer at the Jumping Run Creek sites, while for the Pettiford Creek site, FC export was highest during September‐November. The cause of the seasonal variability was unknown but was thought to be associated with human activity in the watersheds.  相似文献   
67.
The goal of this study was to determine the removal efficiencies of chromium, copper, lead, nickel, and zinc from raw wastewater by chemically enhanced primary treatment (CEPT) and to attain a total suspended solids removal goal of 80%. Operating parameters and chemical doses were optimized by bench-scale tests. Locally obtained raw wastewater samples were spiked with heavy metal solutions to obtain representative concentrations of metals in wastewater. Jar tests were conducted to compare the metals removal efficiencies of the chemical treatment options using ferric chloride, alum, and anionic polymer. The results obtained were compared with those from other studies. It was concluded that CEPT using ferric chloride and anionic polymer is more effective than CEPT using alum for metals removal. The CEPT dosing of 40 mg/L ferric chloride and 0.5 mg/L polymer enhanced heavy metals removal efficiencies by over 200% for chromium, copper, zinc, and nickel and 475% for lead, compared with traditional primary treatment. Efficient metals capture during CEPT can result in increased allowable headworks loadings or lower metal levels in the outfall.  相似文献   
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