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1.
A total of 285 water samples were collected from 71 roof harvested rainwater tanks from four villages in different provinces over a two-year (2013–2014) period during the early (October to December) and late (January to March) rainy season. Water quality was evaluated based on Escherichia coli, faecal coliforms and Enterococcus spp. prevalence using the IDEXX Quanti-Tray quantification system. Real-Time PCR was used to analyse a subset of 168 samples for the presence of Shigella spp., Salmonella spp. and E. coli virulence genes (stx1, stx2 and eaeA). Escherichia coli were detected in 44.1% of the samples, Enterococcus spp. in 57.9% and faecal coliforms in 95.7%. The most prevalent E. coli concentrations in harvested rainwater were observed in 29.1% of samples and 22.5% for Enterococcus spp. and, were within 1–10 cfu/100 ml and 10–100 cfu/100 ml, respectively, whereas those for faecal coliforms (36.6%) were within 100–1000 cfu/100 ml. On average 16.8% of the samples had neither E. coli nor Enterococcus spp. detected, while 33.9% had only Enterococcus spp. and 23.7% had only E. coli. E. coli and Enterococcus spp. were detected together in 25.5% of the samples. Evaluation of samples for potential pathogenic bacteria showed all tested samples to be negative for the Shigella spp. ipaH gene, while five tested positive for Salmonella ipaB gene. None of the samples tested positive for the stx1 and stx2 genes, and only two tested positive for the eaeA gene. These findings are potentially useful in the development of a simplified risk assessment strategy based on the concentrations of indicator bacteria.  相似文献   
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In this study, a bacterial strain able to use sulcotrione, a β-triketone herbicide, as sole source of carbon and energy was isolated from soil samples previously treated with this herbicide. Phylogenetic study based on16S rRNA gene sequence showed that the isolate has 100 % of similarity with several Bradyrhizobium and was accordingly designated as Bradyrhizobium sp. SR1. Plasmid profiling revealed the presence of a large plasmid (>50 kb) in SR1 not cured under nonselective conditions. Its transfer to Escherichia coli by electroporation failed to induce β-triketone degrading capacity, suggesting that degrading genes possibly located on this plasmid cannot be expressed in E. coli or that they are not plasmid borne. The evaluation of the SR1 ability to degrade various synthetic (mesotrione and tembotrione) and natural (leptospermone) triketones showed that this strain was also able to degrade mesotrione. Although SR1 was able to entirely dissipate both herbicides, degradation rate of sulcotrione was ten times higher than that of mesotrione, showing a greater affinity of degrading-enzyme system to sulcotrione. Degradation pathway of sulcotrione involved the formation of 2-chloro-4-mesylbenzoic acid (CMBA), previously identified in sulcotrione degradation, and of a new metabolite identified as hydroxy-sulcotrione. Mesotrione degradation pathway leads to the accumulation of 4-methylsulfonyl-2-nitrobenzoic acid (MNBA) and 2-amino-4 methylsulfonylbenzoic acid (AMBA), two well-known metabolites of this herbicide. Along with the dissipation of β-triketones, one could observe the decrease in 4-hydroxyphenylpyruvate dioxygenase (HPPD) inhibition, indicating that toxicity was due to parent molecules, and not to the formed metabolites. This is the first report of the isolation of bacterial strain able to transform two β-triketones.  相似文献   
3.
Self-Organizing Maps have been used on monitoring sites in several Scheldt sub-basins to identify the main aquatic invertebrate assemblages and relate them to the physico-chemical and toxic water status. 12 physico-chemical variables and 2 estimates of toxic risk were available for a dataset made up of a total of 489 records. Two of the five defining clusters reflecting a relatively clean environment were composed by very well diversified functional feeding groups and sensitive taxa. The cleanest assemblage was mainly linked to the sites from the Nete sub-basin. The three other clusters were inversely described with a dominance of oligochaetes and deposit feeders as well as a bad water quality.Such an analysis can be used to support ecological status assessment of rivers and thus might be useful for decision-makers in the evaluation of chemical and toxic water status, as required by the EU Water Framework Directive.  相似文献   
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The distribution of breeding resources, such as nest sites, can have a pronounced impact on a population by affecting the proportion of individuals that succeed to breed and hence, the variation in reproductive success. Aggregation of important resources can lead to resource monopolisation by a limited number of individuals and thus affect the intensity of sexual selection. In this study, we tested, by contrasting two experimental treatments (dispersed vs. aggregated), how nest distribution affects: (1) mating behaviour, (2) male nest occupation and mating success, and (3) reproductive success and the opportunity for selection. We used the two-spotted goby (Gobiusculus flavescens), a small marine fish with a resource-based mating system, as our model species. When nests were aggregated, a larger proportion of the males behaved aggressively, fewer males succeeded in occupying a nest, fewer males became mated, and those males that mated received fewer eggs from spawning females. These effects resulted in a higher variance in reproductive success and hence, a higher opportunity for selection (I rs ), in the aggregated treatment. We suggest that the results are a direct consequence of males defending a territory around their nest, preventing competitively inferior males from breeding. However, we found no significant selection differentials for body length or condition of males in either treatment. Our results support the hypothesis that aggregation of essential resources like nests promotes resource monopolisation. In species facing highly clumped nesting resources in the wild, monopolisation may negatively impact population productivity but could lead to strong selection on traits that promote male competitive ability.  相似文献   
5.
As the use of ultrasonography has become a routine procedure in the care of pregnant women, fetal congenital malformations have been frequently diagnosed prenatally. During a 4-year period abdominal wall defects (AWD) were diagnosed in 14 cases, five were gastroschises and nine were omphaloceles, seven females and seven males. Concomitant malformations were present in one case of gastroschisis and in five cases of omphalocele. Eleven AWD's were diagnosed in the second trimester and six pregnancies were interrupted. Eight children with AWD were born; two boys with omphalocele and one girl and one boy with gastroschisis are still alive. Alpha-fetoprotein was determined in amniotic fluid in 11 cases and also in maternal serum prior to the amniocentesis in eight cases. Chromosomal investigations were performed in 13 cases, 11 on amniotic fluid cells and two on lymphocytes from a blood sample made postnatally. Two abnormal karyotypes, 47,XX + 18 were found.  相似文献   
6.
Certified management systems have increasingly been applied by firms in recent decades and now cover the management of health and safety, principally through the OHSAS 18001 standard. In order to become certified, firms must not only observe the relevant legislation, but also improve performance and raise goals within health and safety on a continuous basis. The article examines how certified occupational and health management systems influence this process to evaluate how far they hinder or support learning. It presents a model with which it is possible to identify and analyse improvement processes. The model is applied to five cases from a qualitative study of Danish manufacturers with certified health and safety management systems. The cases illustrate the wide variation in health and safety management among certified firms.Certification is found to support lower levels of continuous improvement performance in handling health and safety issues. However, more advanced improvement practices are shown to be connected to the integration of health and safety in other managerial areas, as well as to the employment of similar advanced improvement processes within firms. The article argues that certified health and safety management does not obstruct learning, and can support advanced learning. Improvement practices with regard to health and safety are mainly dependent upon the firm’s overall organisational processes and do not automatically arise from the standard alone.  相似文献   
7.
Juberg–Hayward syndrome is a rare autosomal recessive syndrome characterised by the association of growth retardation, microcephaly, cleft lip and palate, and thumb and radial ray abnormalities. To date, no prenatal cases have been reported. Here, we report on the first prenatal case of Juberg–Hayward syndrome. The diagnosis was established following fetopathological study. Besides the cardinal features of the syndrome, this prenatal case was remarkable for the severity of the short arm malformation and by the finding of big toe agenesis and cerebral abnormalities including hydrocephalus, agenesis of corpus callosum, and cerebellar hypoplasia. We conclude that the diagnosis of Juberg–Hayward syndrome can be discussed prenatally following ultrasound diagnosis of the association of intrauterine growth restriction, microcephaly, thumb/radial anomalies, and cleft lip/palate. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
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