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161.
The Capital Region of Denmark tested the Multi Increment Sampling® (MIS) technology at 14 children's playgrounds in the region to assess whether the method provides representative test results and an improved foundation for risk assessment. The purpose of the investigation was to determine whether the previous uses of the playground areas have led to soil contamination that poses a health risk to its current users (children). The unpaved areas of the playgrounds were divided into decision units based on historical data along with the expected patterns of movement from its users. The samples from each unit consisted of 45 to 100 increments were collected from three depths within the upper one‐half meter. Furthermore, triplicate samples were taken from the upper sampling depth in at least one unit for quality control purposes. The investigation results showed excellent consistency between the pollution parameters and contamination levels in different decision units for each playground. The decision units where high levels of soil contamination exist coincide well with the previous site history. The MIS method has proven to be expensive and time consuming. However, in the future it will be easier to implement as we gain more experience with use of this method.  ©2016 Wiley Periodicals, Inc.  相似文献   
162.
Assessment of the flammability of ornamental vegetation (particularly hedges) planted around houses is necessary in light of the increasing urbanization of the wildland–urban interfaces (WUIs) and the high fire occurrence in such areas. The structure and flammability of seven of the species most frequently planted as hedges in Provence (southeastern France) were studied at particle level. Spatial repartition of the different types of fuel particles within plants was assessed by means of the cube method. The leaf flammability was assessed using an epiradiator as a burning device, and measurements of foliar physical characteristics and gross heat of combustion (GHC) helped to explain the results of burning experiments. Co-inertia analysis revealed that species with thin leaves were quick to ignite (Pyracantha coccinea, Phyllostachys sp.) and species with high leaf GHC burned the longest (Pittosporum tobira, Nerium oleander). Species presenting high ignitability (Photinia fraseri, Phyllostachys sp. and Pyracantha coccinea) were characterized by high foliar surface area-to-volume ratio, and species presenting lower ignitability were characterized by high GHC (Pittosporum tobira, Nerium oleander, Cupressus sempervirens). Hierarchical cluster analysis of the flammability variables (ignition frequency, time-to-ignition and flaming duration) categorized the relative flammability of the seven species (including dead Cupressus sempervirens) in five clusters of species from poorly flammable (Pittosporum tobira) to extremely flammable (dead Cupressus sempervirens).This study provides useful information for reducing fire risk in WUIs in the study area.  相似文献   
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Congenital diaphragmatic hernia (CDH) can be associated with genetic or structural anomalies with poor prognosis. In isolated cases, survival is dependent on the degree of lung hypoplasia and liver position. Cases should be referred in utero to tertiary care centers familiar with this condition both for prediction of outcome as well as timed delivery. The best validated prognostic indicator is the lung area to head circumference ratio. Ultrasound is used to measure the lung area of the index case, which is then expressed as a proportion of what is expected normally (observed/expected LHR). When O/E LHR is < 25% survival chances are < 15%. Prenatal intervention, aiming to stimulate lung growth, can be achieved by temporary fetal endoscopic tracheal occlusion (FETO). A balloon is percutaneously inserted into the trachea at 26–28 weeks, and reversal of occlusion is planned at 34 weeks. Growing experience has demonstrated the feasibility and safety of the technique with a survival rate of about 50%. The lung response to, and outcome after FETO, is dependent on pre-existing lung size as well gestational age at birth. Early data show that FETO does not increase morbidity in survivors, when compared to historical controls. Several trials are currently under design. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
166.
This research investigated whether the psychological wellbeing of earthquake survivors two years after the traumatic event would vary as a function of type of temporary housing. A comparison of people assigned to containers, converted into mobile homes, vs. wooden dachas vs. a control group, that had not lost their homes in the earthquake, revealed reliable effects of housing type. Compared to those in containers, earthquake victims assigned to dachas were more satisfied with and more attached to their temporary homes and reported greater psychological wellbeing (fewer psychological stress symptoms, less discomfort and a lesser feeling of being dominated by the situation). Also, home attachment and satisfaction with one's home mediated the psychological wellbeing, suggesting that the attitudes towards different types of temporary housing play a causal role in post-traumatic stress reactions. Practical implications for emergency interventions following natural disasters are discussed.  相似文献   
167.
The study aimed to assess the quality and health aspects of water intended for human and livestock consumption in two rural districts of the Rift Valley of Ethiopia. The study involved two parts: the first consisted of a questionnaire survey and farmers’ group discussions, complemented by secondary health data, and the second part determined the chemical (total dissolved solids, pH, manganese, hexa-valent chromium, fluoride) and microbiological quality of different water sources during dry and wet seasons. The result showed a lack of sustainable access to safe water in the communities. Industrial pollution and mismanagement of water sources by human and livestock was found to be a source of potential health risk. Potentially linked human health problems like malaria, diarrhoea and gastrointestinal parasites were common in the districts. Overall, 76 % of the assessed water sources (n?=?25) failed to comply with World Health Organization guidelines for human drinking water, for at least one assessed parameter, mostly irrespective of the season. The non-compliance was mainly attributed to Escherichia coli contamination and/or high fluoride concentration. At least 20 % of the water samples were also found to be unfit for livestock consumption based on assessed chemical parameters in both dry and wet seasons. To minimize the health risk associated with mismanagement and poor quality of water sources in the area, targeted action in the protection of surface water sources should be given priority.  相似文献   
168.
Degradation of biochanin A, 400 μg (1.41 μmol) per gram of dry soil, was studied and the initial degradation products, dihydrobiochanin A, pratensein and genistein were identified and quantified. The maximum concentrations of these compounds were determined as 166 pmol/g dry soil after 2 days of incubation, 175 pmol/g dry soil after 1 day and 1,236 pmol/g dry soil after 1 day, respectively. Biochanin A and the initially formed products degrade too fast to be responsible for clover soil sickness (DT90 <20 days), but could be precursors for the responsible compounds. The immediate degradation products from biochanin A are all biologically active and are the prime candidates for a reduction of weed pressure caused by clover.  相似文献   
169.
Levels of ultraviolet-B radiation (UV-B: 280–315 nm) reaching the earth’s surface have increased over the past few decades due to ozone depletion. It is well documented that exposure to UV-B radiation increases mortality in marine fish larvae. However, few studies have examined sub-lethal effects of UV-B radiation such as, for example, the possibility that it affects prey consumption by fish larvae. Atlantic cod larvae were exposed to a sub-lethal level of ultraviolet-B radiation (UV-B: 280–315 nm) for 15 h. After the exposure, rotifers (4/mL) were fed to cod larvae at three different post-exposure intervals (20 min, 3 and 6 h). Trials were replicated three times for each post-exposure interval. The number of rotifers in the gut and the percent of empty guts (number of fish with empty gut/number of fish examined × 100) were analyzed. Results were compared to those of unexposed fish (the control treatment). UV-B exposed cod larvae had consumed significantly fewer rotifers than control fish at all post-exposure intervals. There was no significant difference in the frequency of empty guts between fish in the UV-B treatment versus fish in the control treatment at any of the post-exposure time points (although the difference at 20 min post-exposure was borderline significant). These observations suggest that cod larvae exposed to sub-lethal levels of UV-B have lower net energy gain which may lead to reduced growth rate and possibly poorer survival.  相似文献   
170.
The heterogeneous ozonolysis of naphthalene adsorbed on XAD-4 resin was studied using an annular denuder technique. The experiments involved depositing a known quantity of naphthalene on the XAD-4 resin and then measuring the quantity of the solid naphthalene that reacted away under a constant flow of gaseous ozone (0.064 to 4.9 ppm) for a defined amount of time. All experiments were performed at room temperature (26 to 30 °C) and atmospheric pressure. The kinetic rate coefficient for the ozonolysis reaction of naphthalene adsorbed on XAD-4 resin is reported to be (10.1?±?0.4)?×?10?19 cm3 molecule?1 s?1 (error is 2σ, precision only). This value is five times greater than the currently recommended literature value for the homogeneous gas phase reaction of naphthalene with ozone. The obtained rate coefficient is used to evaluate reaction artifacts from field concentration measurements of naphthalene, acenaphthene, and phenanthrene. The observed uncertainties associated with field concentration measurements of naphthalene, acenaphthene, and phenanthrene are reported to be much higher than the uncertainties associated with the artifact reactions. Consequently, ozone reaction artifact appears to be negligible compared to the observed field measurement uncertainty results.  相似文献   
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