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1.
A good water supply and wastewater management is essential for a local sustainable community development. This is emphasized in the new global goals of the UN Sustainable Development, where the sixth objective is to: “Ensure availability and sustainable management of water and sanitation for all” (United Nations 2015). This obviously raises the question of how this can be achieved considering the very different conditions and cultures around the globe. This article presents the Greenlandic context and elucidates the current Greenland water supply system and wastewater management system from a socio-technical approach, focusing on the geographic, climatic and cultural challenges. The article identifies a diverse set of system constellations in different parts of Greenland and concludes with a discussion of health and quality of life implications.  相似文献   
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Previous studies show that conservation actions have prevented extinctions, recovered populations, and reduced declining trends in global biodiversity. However, all studies to date have substantially underestimated the difference conservation action makes because they failed to account fully for what would have happened in the absence thereof. We undertook a scenario‐based thought experiment to better quantify the effect conservation actions have had on the extinction risk of the world's 235 recognized ungulate species. We did so by comparing species’ observed conservation status in 2008 with their estimated status under counterfactual scenarios in which conservation efforts ceased in 1996. We estimated that without conservation at least 148 species would have deteriorated by one International Union for Conservation of Nature (IUCN) Red List category, including 6 species that now would be listed as extinct or extinct in the wild. The overall decline in the conservation status of ungulates would have been nearly 8 times worse than observed. This trend would have been greater still if not for conservation on private lands. While some species have benefited from highly targeted interventions, such as reintroduction, most benefited collaterally from conservation such as habitat protection. We found that the difference conservation action makes to the conservation status of the world's ungulate species is likely to be higher than previously estimated. Increased, and sustained, investment could help achieve further improvements.  相似文献   
3.
Among the separation techniques used in industries, the triboelectric separation of insulating particles using a rotary tube is an effective way employed in the waste recovery of plastic and mineral products. This process, also called free-fall triboelectric separation, is widely used for the sorting of granular mixtures resulting from industrial plastic wastes. Given that the robustness of such a separation process is an important issue, a standard procedure is used for determining the set point and for minimising the process sensitivity of sorting mixed particles of different polymers to changes in the values of some critical factors. The aim of this paper was to analyse the efficiency of the triboelectric separation process of polymers with respect to any slight variation in the values of the most significant factors. Experiments with a sample of high-density polyethylene and polyvinyl chloride plastic granules were carried out on a laboratory experimental bench. Several one-factor-at-a-time experiments, followed by two factorial designs (one composite and the other fractional), were performed based on the following experimental procedure: (1) determination of the variation limits of the input variables; (2) identification of the set point and (3) robustness testing of the process, i.e. testing whether the performance of the system remains high even when the factors vary slightly around the set point.  相似文献   
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Objectives

The aim of this study was to evaluate the role of fetal magnetic resonance imaging (MRI) as a complement to ultrasound (US) in the prenatal diagnosis of craniofacial anomalies.

Methods

A historical cohort study including all pregnant women who were referred for fetal MRI because of antenatal diagnosis of craniofacial anomalies on screening US. Prenatal diagnostic US, MRI, and postnatal diagnosis were compared for consistencies and discrepancies.

Results

Forty-five pregnant women with 73 suspected fetal craniofacial anomalies diagnosed by US underwent MRI. In 40 out of 73 anomalies (54.8%), US and MRI findings were in complete agreement with postnatal diagnoses. MRI correctly ruled out the diagnosis of 24 anomalies suspected on US and diagnosed four additional pathologies that were not demonstrated by US. Out of the 85 anomalies (suspected by imaging or confirmed postnatally), confident diagnosis could be made by MRI in 68 anomalies (80%), not diagnosed in 10 (11.8%), and over-diagnosed in seven (8.2%). By US, confident diagnosis could be made in 44 anomalies (51.8%), not diagnosed in 11 (12.9%), and over-diagnosed in 30 (35.3%).

Conclusion

MRI is valuable in the antenatal evaluation of fetal craniofacial anomalies and may be useful as an adjunct to US in the prenatal work-up of craniofacial anomalies.  相似文献   
7.
An impact related daily air quality index (DAQx), calculated for 15 air quality monitoring stations (traffic, background, and industry) in Belgium, France, Germany and Luxembourg, was compared to mesoscale atmospheric patterns between 2001 and 2007. Meteorological conditions were described by the Hess and Brezowsky synoptic weather classification system and gridded data of the EU FP6 ENSEMBLES project of total precipitation and mean surface temperature. DAQx values indicate sufficient to poor air quality in the urban area of Brussels and at urban traffic stations, as well as satisfactory air quality at the background stations. The air quality index refers to more than 90% to the presence of high PM10, O3 and NO2 concentrations. SO2 and CO play only a minor role. The investigation of weather regimes indicates that zonal and mixed cyclonic circulation regimes are associated with better air quality than meridional and anticyclonic weather regimes. In general, weather regimes with high daily precipitation lead to better air quality than dryer air masses because of lower contribution of PM10 to the air quality index. A trend analysis of weather regimes from 1978 to 2007 shows significant (α = 0.05) positive trends for weather classes associated with lower PM10 concentrations. The results of a case study at a German station examining the relationship between PM10 concentrations and local meteorological quantities (wind speed and precipitation) confirm the results of the regional analysis.  相似文献   
8.
To avoid eutrophication of receiving waters, effective methods to remove P in urban and agricultural runoff are needed. Crushed concrete may be an effective filter material to remove dissolved and particulate P. Five types of crushed concrete were tested in the laboratory to evaluate the retention capacity of dissolved P. All types removed P very effectively (5.1-19.6 g P kg(-1) concrete), while the possible release of bound P varied between 0.4 and 4.6%. The retention rate was positively related to a decreasing concrete grain size due to an increasing surface area for binding. The P retention was also related to a marked increase in pH (up to pH 12), and the highest retention was observed when pH was high. Under these circumstances, column experiments showed outlet P concentrations <0.0075 mg P L(-1). Furthermore, experiments revealed that release of heavy metals is of no importance for the treated water. We demonstrate that crushed concrete can be an effective tool to remove P in urban and agricultural runoff as filter material in sedimentation/infiltration ponds provided that pH in the treated water is neutralized or the water is diluted before outlet to avoid undesired effects caused by the high pH.  相似文献   
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Improving biodegradability of PVA/starch blends is a reality already documented by a number of works. Admittedly, mechanical properties of products (for example, tensile strength) are somewhat worse, but suitable composition optimizing or chemical modifying of starch may eliminate the problem to a large degree. This work is an attempt to find another potential effect influencing biodegradability, that of technological procedure for producing films from these blends on an extruder. The procedure with a so-called pre-extrusion step (two-stage) and dry-blend (single-stage) produced blends of slightest differences in achieved biodegradability (virtually within limits of experimental error) in aerobic (76 vs. 79%) as well as anaerobic breakdown (48 vs. 52%). Conversely, morphological analysis exhibited superior homogeneity of films prepared by the two-stage process; their tensile strength was also higher.  相似文献   
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