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141.
In this study, a multi-criteria methodology is proposed to identify and prioritize interventions for water quality improvement with the aid of computer simulation models. The methodology can be used to elaborate and compare future socio-economic development scenarios to select the best interventions based on three criteria: (1) ideas of experts and stakeholders about the importance of scenarios, (2) impacts of each scenario on surface water quality in watershed, and (3) benefit–cost analysis for each scenario. A score is computed for each scenario based on a weighted sum technique which enables to take into consideration different level of importance for the three criteria. The methodology is applied to Cau River basin in Vietnam, with the aid of a computer tool, to assess interventions for river water quality improvement within the context of population growth and urbanization. The results show that fast future population growth in upstream has significant impacts. In 2020, an increase of 116 % of the population in Bac Kan town can lead to an increase of 120 and 135 % in BOD5 and NH4 + median concentrations, respectively, with the implementation of a treatment plant for 10,000 people in Bac Kan town. Therefore, the increase of the domestic wastewater treatment plant’s capacity in Bac Kan town, at least twice as the projection of local government, is necessary. These results will help decision makers to select the best interventions for Cau River basin management.  相似文献   
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Goudet S  Griffths P  Bogin BA 《Disasters》2011,35(4):701-719
Maternal nutritional status is a determinant of child health. This paper studies the association between a mother's body mass index (BMI) and her infant's nutritional status over a one year time frame after the 1998 flood crisis in Bangladesh. The paper uses secondary analysis of data collected from 757 households in seven rural areas of Bangladesh affected by the 1998 flood using multiple-stage probability sampling techniques (n = 143). Logistic regression models were employed to investigate the predictive impact of maternal BMI on infant's nutritional status after controlling for a range of child and maternal factors. An underweight mother was a significant factor with regard to the risk of infants suffering stunting (odds ratio (OR) = 4.45, 95 per cent confidence interval (CI) = 1.04-18.94) and being underweight (OR = 3.51, 95 per cent CI = 1.02-12.05) a year later, but not wasting (OR = 2.09, 95 per cent CI = 0.51-8.67). The findings suggest that there is a post-emergency link between maternal and infant nutritional health.  相似文献   
144.
Studies that focus on single predator-prey interactions can be inadequate for understanding antipredator responses in multi-predator systems. Yet there is still a general lack of information about the strategies of prey to minimize predation risk from multiple predators at the landscape level. Here we examined the distribution of seven African ungulate species in the fenced Karongwe Game Reserve (KGR), South Africa, as a function of predation risk from all large carnivore species (lion, leopard, cheetah, African wild dog, and spotted hyena). Using observed kill data, we generated ungulate-specific predictions of relative predation risk and of riskiness of habitats. To determine how ungulates minimize predation risk at the landscape level, we explicitly tested five hypotheses consisting of strategies that reduce the probability of encountering predators, and the probability of being killed. All ungulate species avoided risky habitats, and most selected safer habitats, thus reducing their probability of being killed. To reduce the probability of encountering predators, most of the smaller prey species (impala, warthog, waterbuck, kudu) avoided the space use of all predators, while the larger species (wildebeest, zebra, giraffe) only avoided areas where lion and leopard space use were high. The strength of avoidance for the space use of predators generally did not correspond to the relative predation threat from those predators. Instead, ungulates used a simpler behavioral rule of avoiding the activity areas of sit-and-pursue predators (lion and leopard), but not those of cursorial predators (cheetah and African wild dog). In general, selection and avoidance of habitats was stronger than avoidance of the predator activity areas. We expect similar decision rules to drive the distribution pattern of ungulates in other African savannas and in other multi-predator systems, especially where predators differ in their hunting modes.  相似文献   
145.

Objective

To perform a systematic review and meta-analysis of the available literature on low fetal fraction (LFF) in cell-free DNA (cfDNA) screening and the risk of fetal chromosomal aberrations.

Method

We searched articles published between January 2010 and May 2021 in PubMed and EMBASE databases. Risk of bias was assessed using QUADAS-2.

Results

Twenty-seven studies met the inclusion criteria, comprising data of 243,700 singleton pregnancies. Compared to normal fetal fraction, LFF was associated with a higher risk of trisomy 13 (OR 5.99 [3.61–9.95], I 2 of heterogeneity = 0%, n = 22 studies), trisomy 18 (OR 4.46 [3.07–6.47], I 2 = 0%, n = 22 studies), monosomy X (OR 5.88 [2.34–14.78], I 2 = 18%, n = 10 studies), and triploidy (OR 36.39 [9.83–134.68], I 2 = 61%, n = 6 studies), but not trisomy 21 (OR 1.25 [0.76–2.03], I 2 = 36%, n = 23 studies). LFF was also associated with a higher risk of various other types of fetal chromosomal aberrations (OR 4.00 [1.78–9.00], I 2 = 2%, n = 11 studies). Meta-analysis of proportions showed that absolute rates of fetal chromosomal aberrations ranged between 1% and 2% in women with LFF. A limitation of this review is the potential risk of ascertainment bias because of differences in outcome assessment between pregnancies with LFF and those with normal fetal fraction. Heterogeneity in population characteristics or applied technologies across included studies may not have been fully addressed.

Conclusion

An LFF test result in cfDNA screening is associated with an increased risk of fetal trisomy 13, trisomy 18, monosomy X, and triploidy, but not trisomy 21. Further research is needed to assess the association between LFF and other specific types of fetal chromosomal aberrations.  相似文献   
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147.

Objectives

To define the prognostic markers of fetal dilated bowel loops.

Methods

National non-interventional study of 133 consecutive prenatal observations of dilated loops including ultrasound examinations, complementary laboratory tests, magnetic resonance imaging (MRI), outcomes, and postnatal diagnosis.

Results

One hundred twenty seven cases were classified according to outcome: Group 1, very severe (n = 43), Group 2, children needing specific care (n = 39), and Group 3, healthy children (n = 45). Prenatal ultrasound scan suggested duodenal obstruction in 30 cases, small bowel obstruction in 81, colonic obstruction in 11, and diffuse dilatation in 5. Diameter of dilated loops did not significantly differ between the groups. A poor prognosis was significantly associated with duodenal obstruction, genetic anomalies (53% vs. 21.8%), including aneuploidies or CFTR gene mutations and abnormal amniotic fluid biochemistry (86.4% vs. 38.7%). A good prognosis was associated with regression of dilatation and normal MRI.

Conclusion

In this study, postnatal outcomes for fetuses with intestinal dilatation were best predicted by assessing the level of obstruction with prenatal ultrasound and MRI, determining the presence of associated malformations, amniotic fluid biochemical and genetic testing, and monitoring for regression of bowel dilatation. These results should help inform future guidelines on the prenatal and neonatal management of congenital intestinal obstruction.  相似文献   
148.
Environmental Science and Pollution Research - Turkey is one of the major plastic pollution sources in the Mediterranean and the Black Sea. This review summarizes present information, data, and...  相似文献   
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