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1.
AsayofsomevolatilecompoundsinhumanexhalationQinTao,XuXiaobaiResearchCenterforEcoEnvironmentalSciences,ChineseAcademyofScie...  相似文献   
2.
We report a series of 350 patients submitted to transabdominal chorionic villus sampling (CVS). A technique using two ultrasound-guided needles and a suction pump was used. In most cases, the procedure was performed between 9 and 13 weeks. Twenty-one pregnancies were selectively terminated; nine spontaneous abortions followed the procedure and one fetal loss after 28 weeks was recorded; 153 pregnancies are in progress and 169 delivered fetuses are alive and well. Transabdominal biopsy is a feasible and effective technique for CVS.  相似文献   
3.
Climate and land-use/cover changes (LUCC) influence soil erosion vulnerability in the semi-arid region of Alqueva, threatening the reservoir storage capacity and sustainability of the landscape. Considering the effect of these changes in the future, the purpose of this study was to investigate soil erosion scenarios using the Revised Universal Soil Loss Equation (RUSLE) model. A multi-agent system combining Markov cellular automata with multi-criteria evaluation was used to investigate LUCC scenarios according to delineated regional strategies. Forecasting scenarios indicated that the intensive agricultural area as well as the sparse and xerophytic vegetation and rainfall-runoff erosivity would increase, consequently causing the soil erosion to rise from 1.78 Mg ha?1 to 3.65 Mg ha?1 by 2100. A backcasting scenario was investigated by considering the application of soil conservation practices that would decrease the soil erosion considerably to an average of 2.27 Mg ha?1. A decision support system can assist stakeholders in defining restrictive practices and developing conservation plans, contributing to control the reservoir's siltation.  相似文献   
4.
Heavy metal contamination is a long-standing and very well-known public health problem, and its exposure can cause damage to several organs of human body, especially on the central nervous system of young children and teenagers. The aim of this article is to evaluate lead, cadmium, and manganese contamination in 125 children from 6 to 13 years old living in contaminated areas during the period from 2006 to 2009 (São Vicente, Cubatão Downtown, Bertioga and Cubatão Pilões/Água Fria). This estuary area is the most important example of environmental degradation by chemicals from industrial sources. This is a cross-sectional study through clinical examinations and dental enamel tests. All mothers from these children lived in the area since before the pregnancy. Lead, cadmium, and manganese levels (μg/g) were measured on dental enamel samples through graphite furnace atomic absorption spectrometry, searching for the occurrence of heavy metals. The mean lead concentrations were 139.48 μg/g in Cubatão Pilões/Água Fria, 170.45 μg/g in Cubatão Downtown, 213.52 μg/g in São Vicente, and 151.89 μg/g in Bertioga. The mean cadmium concentrations were 10.83 μg/g in Cubatão Pilões/Água Fria, 12.58 μg/g in Cubatão Downtown, 10.92 μg/g in São Vicente, and 14.57 μg/g in Bertioga. The mean manganese concentrations were 23.49 μg/g in Cubatão Pilões/Água Fria, 30.90 μg/g in Cubatão Downtown, 41.46 μg/g in São Vicente, and 42.00 μg/g in Bertioga. Dental surface enamel may be used as an efficient biomarker of past environmental exposure to lead, manganese, and cadmium which are associated to well-known sources of heavy metal contamination. The results suggest that the evaluated children were exposed to sources of lead, cadmium, and manganese since before their conceptions. Although Bertioga initially was chosen as a control area of this study, it was also was verified to have heavy metal contamination on examined children.  相似文献   
5.
Since it was commercially introduced in 1974, glyphosate has been one of the most commonly used herbicides in agriculture worldwide, and there is growing concern about its adverse effects on the environment. Assuming that glyphosate may increase the organic turbidity of water bodies, we evaluated the effect of a single application of 2.4?±?0.1 mg l?1 of glyphosate (technical grade) on freshwater bacterioplankton and phytoplankton (pico, micro, and nanophytoplankton) and on the physical and chemical properties of the water. We used outdoor experimental mesocosms under clear and oligotrophic (phytoplanktonic chlorophyll a?=?2.04 μg l?1; turbidity?=?2.0 NTU) and organic turbid and eutrophic (phytoplanktonic chlorophyll a?=?50.3 μg l?1; turbidity?=?16.0 NTU) scenarios. Samplings were conducted at the beginning of the experiment and at 1, 8, 19, and 33 days after glyphosate addition. For both typologies, the herbicide affected the abiotic water properties (with a marked increase in total phosphorus), but it did not affect the structure of micro and nanophytoplankton. In clear waters, glyphosate treatment induced a trend toward higher bacteria and picoeukaryotes abundances, while there was a 2 to 2.5-fold increase in picocyanobacteria number. In turbid waters, without picoeukaryotes at the beginning of the experiment, glyphosate decreased bacteria abundance but increased the number of picocyanobacteria, suggesting a direct favorable effect. Moreover, our results show that the impact of the herbicide was observed in microorganisms from both oligo and eutrophic conditions, indicating that the impact would be independent of the trophic status of the water body.  相似文献   
6.
Starch-based composite films have been proposed as food packaging. In this context, the study of non-conventional starch sources (sagu, Canna edulis Kerr) has worldwide special attention, because these materials can impart different properties as carbohydrate polymers. A thorough study of the matrices used (sagu starch and flour) was carried out. In the same way, thermoplastic starch (TPS)/PCL blend and thermoplastic flour (TFS)/PCL blend were obtained by melt mixing followed by compression moulding containing glycerol as plasticizer. In this study, chemical composition of the matrices and their properties were related with the properties of the developed films. Moisture content, water solubility, X-ray diffraction, thermogravimetric analysis and mechanical and microstructural properties were evaluated in the films. Taking into account the results, the sagu flour has great potential as starchy source for food packaging applications. However, concretely the flour had lower compatibility with the PCL compared to the starch/PCL blend.  相似文献   
7.
Environmental Science and Pollution Research - The scientific knowledge produced by academic research can be valued in all sectors of human activity, including private sector. The ROVALTAIN...  相似文献   
8.
Environmental Science and Pollution Research - Dimethoate ([O,O-dimethyl S-(N-methylcarbamoylmethyl) phosphorodithioate]) is an organophosphate insecticide and acaricide widely used for...  相似文献   
9.
To collect regional information on internal levels of pollutants in humans in Flanders, 1196 mother–child pairs were systematically recruited in 2002–2003 via 25 maternities across Flanders. Cd, Pb, PCB congeners 118, 170, 138, 153 and 180, p,p′-DDE — a key metabolite of DDT- and hexachlorobenzene (HCB) were measured in cord blood or plasma. Cd was detected in 64% of the samples (geometric mean 0.21 µg/L cord blood). p,p′-DDE (110 ng/g plasma lipids) and Pb (14.7 µg/L blood), were measurable in nearly all samples. The individual PCB congeners could be detected in 40 to 81% of the newborns (138 + 153 + 180 = 64.4 ng/g plasma lipids). HCB (18.9 ng/g plasma lipids) and dioxin-like compounds measured by DR-CALUX® (23 pg CALUX-TEQ/g lipids) were above detection limit in more than 75% of the samples. Age and smoking habits of the mothers, did not influence the cord blood Pb and Cd levels. The organochlorines increased 4 to 9% per year of the mother's age (partial R= 0.05 to 0.22). Mothers had 2.6% less PCBs in cord blood (partial R= 0.02) for each unit increase in pre-pregnancy BMI. Season of delivery, breastfeeding previous children or consumption of local dairy products, were minor determinants. Up to 20% of the variability in organochlorine concentrations was explained by residence area. It was concluded that the place of birth in Flanders is an important determinant of the load of pollutants measured at the start of life. This underlines the validity of human biomonitoring on (relatively) small geographical scale.  相似文献   
10.
Organic matter and nutrients in municipal sewage sludge (SS) and chicken manure (CM) could be recycled and used for land farming to enhance fertility and physical properties of soils. Three soil management practices were used at Kentucky State University Research Farm, Franklin County, to study the impact of soil amendments on kale (Brassica oleracea cv. Winterbar) and collard (Brassica oleracea cv. Top Bunch) yields and quality. The three soil management practices were: (i) SS mixed with native soil at 15 t acre?1, (ii) CM mixed with native soil at 15 t acre?1, and (iii) no-mulch (NM) native soil for comparison purposes. At harvest, collard and kale green plants were graded according to USDA standards. Plants grown in CM and SS amended soil produced the greatest number of U.S. No. 1 grade of collard and kale greens compared to NM native soil. Across all treatments, concentrations of ascorbic acid and phenols were generally greater in kale than in collards. Overall, CM and SS enhanced total phenols and ascorbic acid contents of kale and collard compared to NM native soil. We investigated the chemical and physical properties of each of the three soil treatments that might explain variability among treatments and the impact of soil amendments on yield, phenols, and ascorbic acid contents of kale and collard green grown under this practice.  相似文献   
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