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261.

Mapping social vulnerability is a prominent way to identify regions in which the lack of capacity to cope with the impacts of weather extremes is nested in the social setting, aiding climate change adaptation for vulnerable residents, neighborhoods, or localities. Calculating social vulnerability usually involves the construction of a composite index, for which several construction methods have been suggested. However, thorough investigation of results across methods or applied weighting of vulnerability factors is largely missing. This study investigates the outcome of the variable addition—both with and without weighting of single vulnerability factors—and the variable reduction approach/model on social vulnerability indices calculated for New York City. Weighting is based on scientific assessment reports on climate change impacts in New York City. Additionally, the study calculates the outcome on social vulnerability when using either area-based (person/km2) or population-based (%) input data. The study reveals remarkable differences between indices particularly when using different methods but also when using different metrics as input data. The variable addition model has deductive advantages, whereas the variable reduction model is useful when the strength of factors of social vulnerability is unknown. The use of area-based data seems preferable to population-based data when differences are taken as a measure of credibility and quality. Results are important for all forms of vulnerability mapping using index construction techniques.

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Waste from the beneficiation of fish was composted with crushed grass aiming to characterize their chemical composition and investigate the possibility of the use of the final compost as source of humic acids (HA) able to stimulate the growth of lettuce. Compost presented pH value, C/N ratio, and electrical conductivity that allow its use as an organic fertilizer. The element content was present in the following order of abundance in the compost: P?>?Ca?>?N?>?Mg?>?K?>?Fe?>?Zn?>?Mn?>?Mo?>?Cu, and the humus composition was similar to that observed in others kind of organic residues composted. The high content of oxygen pointed out a high level of oxidation of HA, in line with the predominance of phenolic acidity in the functional groups. The 13C-NMR spectra showed marked resonances due to the presence of lipids and other materials resistant to degradation as methoxy substituent and N-alkyl groups. A concentration of 20 mg L?1 HA increased significantly both dry and wet root matter in lettuce but the CO2 assimilation, stomatal conductance, and number of lateral roots of the plants were not affected. However, increases of 64% in the water-use efficiency was observed due to the HA addition, probably related to the root morphology alteration which resulted in 1.6-fold increase of lateral root average length and due to the higher H+ extrusion activity. Reuse of residues from the fish beneficiation activity by composting may represent a safe tool to increase the value of recycled organic residues and generate HA with potential use as plant growth stimulants.  相似文献   
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ABSTRACT: The shape of a river channel is linked to surrounding land use through interacting hydrologic and geologic processes. This study analyzes the relationship between the change in near‐stream land use and the shape of the adjacent river channel over time. Three watersheds in the foothills of the Venezuelan Andes that have experienced differing degrees of development were studied to determine river channel width, sinuosity, and position relative to surrounding land use. Change in land use over time was obtained from multiple‐date aerial photographs (1946 and 1980) referenced to 1996 Landsat Thematic Mapper (TM) satellite imagery, and verified by field inspection. Measurements of land‐use type and amount and river channel morphology from the two dates were made using geographic information system (GIS) methods. The three watersheds differed in the extent of deforestation, the location of remaining forested land, and how much land‐use change had already occurred by 1946. Change in river channel morphology was greatest at the most deforested sites. Valley shape and channel constraint also had a discernible effect on change in channel morphology. This study introduces a method for analyzing change in coupled terrestrial‐aquatic systems based on multiple‐date, remotely sensed data and GIS analysis of spatial properties. The results document human impacts on river channels through a comparison of multiple watersheds over a 35‐year time interval.  相似文献   
264.
Indigenous Heavy Metal Multiresistant Microbiota of Las Catonas Stream   总被引:1,自引:0,他引:1  
Las Catonas stream (Buenos Aires Metropolitan Area) receives a complex mixture of pollutants from point and diffuse sources because of the agricultural, industrial and urban land uses of its basin. Widespread detection of heavy metals exceeding aquatic life protection levels has occurred in monitoring reconnaissance studies in surface and pore water. As a result of the screening of Cu, Cd, Zn and Pb resistant/tolerant and culturable microbiota, B101N and 200H strains (Pseudomonas fluorescens or putida) were isolated and selected for further studies. They showed 65% Cd and 35% Zn extraction efficiency from aqueous phase. The potential use of these strains in wastewater treatment is currently investigated in order to contribute to decrease heavy metal pollution, a problem affecting every stream of Buenos Aires Metropolitan Area.  相似文献   
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The metaphor ‘open kimono’ has been applied in the business world to connote transparency via the release of all available data to an external party. Here, the author uses this term to discuss the relative advantages and disadvantages of reporting on the presence of rare autosomal aneuploidies detected by massively parallel sequencing of placental cell-free DNA in the plasma of pregnant women. Newly presented data sets from multiple laboratories suggest that autosomal aneuploidies such as trisomies 7, 15, 16, 22, and 8 are easily detectable and are potentially associated with fetal growth restriction, pregnancy loss, and maternal preeclampsia. Furthermore, they may explain false positive results for the common autosomal trisomies (13, 18, and 21) as well as test failures. Thus, release of this information may result in improved clinical utility. At the present time, however, professional societies in various parts of the world differ in their recommendations as to whether or not to release expanded autosomal aneuploidy results beyond the common trisomies. © 2016 John Wiley & Sons, Ltd.  相似文献   
269.
The fetal fraction (FF) is a function of both biological factors and bioinformatics algorithms used to interpret DNA sequencing results. It is an essential quality control component of noninvasive prenatal testing (NIPT) results. Clinicians need to understand the biological influences on FF to be able to provide optimal post-test counseling and clinical management. There are many different technologies available for the measurement of FF. Clinicians do not need to know the details behind the bioinformatics algorithms of FF measurements, but they do need to appreciate the significant variations between the different sequencing technologies used by different laboratories. There is no universal FF threshold that is applicable across all platforms and there have not been any differences demonstrated in NIPT performance by sequencing platform or method of FF calculation. Importantly, while FF should be routinely measured, there is not yet a consensus as to whether it should be routinely reported to the clinician. The clinician should know what to expect from a standard test report and whether reasons for failed NIPT results are revealed. Emerging solutions to the challenges of samples with low FF should reduce rates of failed NIPT in the future. In the meantime, having a “plan B" prepared for those patients for whom NIPT is unsuccessful is essential in today's clinical practice.  相似文献   
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