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711.
This study condenses data acquired during investigations of the virological quality of irrigation water used in production of fresh produce. One hundred and eight samples of irrigation water were collected from five berry fruit farms in Finland (1), the Czech Republic (1), Serbia (2), and Poland (1), and sixty-one samples were collected from three leafy green vegetable farms in Poland, Serbia, and Greece. Samples were analyzed for index viruses of human or animal fecal contamination (human and porcine adenoviruses, and bovine polyoma viruses), and human pathogenic viruses (hepatitis A virus, hepatitis E virus, and noroviruses GI/GII). Both index and pathogenic viruses were found in irrigation water samples from the leafy green vegetables production chain. The data on the presence of index viruses indicated that the highest percentage of fecal contamination was of human origin (28.1 %, 18/64), followed by that of porcine (15.4 %, 6/39) and bovine (5.1 %, 2/39) origins. Hepatitis E virus (5 %, 1/20) and noroviruses GII (14.3 %, 4/28) were also detected. Samples from berry fruit production were also positive for both index and pathogenic viruses. The highest percentage of fecal contamination was of human origin (8.3 %, 9/108), followed by that of porcine, 4.5 % (4/89) and bovine, 1.1 % (1/89) origins. Norovirus GII (3.6 %, 2/56) was also detected. These data demonstrate that irrigation water used in primary production is an important vehicle of viral contamination for fresh produce, and thus is a critical control point which should be integrated into food safety management systems for viruses. The recommendations of Codex Alimentarius, as well as regulations on the use of water of appropriate quality for irrigation purposes, should be followed.  相似文献   
712.
After 30 years of economic reform since opening to the outside world in 1978, China's Gross Domestic Product (GDP) has increased by 150% over the past 15 years. The sustainability of such intense economic activity has been questioned from the perspectives of the social, environmental, and economic dimensions of sustainability. In this study, we assessed the spatial and temporal trends in sustainable development in two sensitive agricultural areas of China: Dezhou district, a well-developed region, and Guyuan district, an underdeveloped region. We used the pressure–state–response (PSR) model and a participatory approach that involved local experts to select and evaluate 27 area-specific indicators, then calculated changes in their values from 1985 to 2002. We aggregated these indicators into dimension- and PSR-specific indices to assess the sustainability of development in both regions. There two regions differed greatly in sustainability, but the current status of sustainable development raises concerns in both areas, especially from the perspective of balancing the three dimensions of sustainability. In 2002, Dezhou district performed well economically, with an index value of 0.78 (where 1.0 = sustainable), followed by environmental and social sustainability (both with index values of 0.48). All three indices have increased since 1985 (by 0.17, 0.25, and 0.13, respectively). In Guyuan district, environmental sustainability was highest (with an index value of 0.73), followed by economic and social sustainability (values of 0.55 and 0.37, respectively), but economic sustainability has decreased by 0.04 since 1985, whereas environmental and social sustainability increased by 0.18 and 0.12, respectively. To promote sustainable regional development, development priorities should be determined by considering both the regional and temporal variation in the three sustainability indices.  相似文献   
713.
714.
In 2010, an estimated 400 to 500 children died of acute lead poisoning associated with artisanal gold mining in Zamfara, Nigeria. Processing of gold ores containing up to 10% lead within residential compounds put residents, especially children, at the highest risk. Principal routes of exposure were incidental ingestion and inhalation of contaminated soil and dusts. Several Nigerian and international health organizations collaborated to reduce lead exposures through environmental remediation and medical treatment. The contribution of contaminated food to total lead exposure was assessed during the environmental health response. Objectives of this investigation were to assess the influence of cultural/dietary habits on lead exposure pathways and estimate the contribution of contaminated food to children's blood lead levels(BLLs). A survey of village dietary practices and staple food lead content was conducted to determine dietary composition, caloric intakes, and lead intake. Potential blood lead increments were estimated using bio-kinetic modeling techniques. Most dietary lead exposure was associated with contamination of staple cereal grains and legumes during post-harvest processing and preparation in contaminated homes. Average post-harvest and processed cereal grain lead levels were 0.32 mg/kg and 0.85 mg/kg dry weight, respectively. Age-specific food lead intake ranged from 7 to 78 μg/day. Lead ingestion and absorption were likely aggravated by the dusty environment, fasting between meals, and nutritional deficiencies. Contamination of staple cereal grains by highly bioavailable pulverized ores could account for as much as 11%–34% of children's BLLs during the epidemic, and were a continuing source after residential soil remediation until stored grain inventories were exhausted.  相似文献   
715.

Objectives

Cystic fibrosis (CF) is one of the most common severe autosomal recessive disorders. Prenatal or preconception CF screening is offered in some countries. A maternal blood sample in early pregnancy can provide circulating trophoblasts and offers a DNA source for genetic analysis of both the mother and the fetus. This study aimed to develop a cell-based noninvasive prenatal test (NIPT) to screen for the 50 most common CF variants.

Methods

Blood samples were collected from 30 pregnancies undergoing invasive diagnostics and circulating trophoblasts were harvested in 27. Cystic fibrosis testing was conducted using two different methods: by fragment length analysis and by our newly developed NGS-based CF analysis.

Results

In all 27 cases, cell-based NIPT provided a result using both methods in agreement with the invasive test result.

Conclusion

This study shows that cell-based NIPT for CF screening provides a reliable result without the need for partner- and proband samples.  相似文献   
716.
Journal of Polymers and the Environment - Poly(lactic acid) (PLA) and PLA/5% Babassu compounds were molten mixed, afterwards aged at temperatures ranging from 50 to 90 °C during 15 to...  相似文献   
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