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701.
A monoclonal antibody-based competitive antibody-coated enzyme-linked immunosorbent assay (ELISA) was developed and optimized for determining chlorpyrifos residue in agricultural products. The IC(50) and IC(10) of this ELISA were 3.3 ng/mL and 0.1 ng/mL respectively. The average recoveries in six agricultural products were between 79.5% and 118.0%, with the intra-assay coefficient of variation being less than 8 %. The limit of detection for all tested products was 30 ng/g. To the best of our knowledge, this assay has the best specificity among all the published research on ELISAs for chlorpyrifos.  相似文献   
702.

Purpose  

The dyes and dye stuffs present in effluents released from textile dyeing industries are potentially mutagenic and carcinogenic. Phytoremediation technology can be used for remediating sites contaminated with such textile dyeing effluents. The purpose of the work was to explore the potential of Glandularia pulchella (Sweet) Tronc. to decolorize different textile dyes, textile dyeing effluent, and synthetic mixture of dyes.  相似文献   
703.
This paper analyses environmental and socio-economic barriers for plantation activities on local and regional level and investigates the potential for carbon finance to stimulate the increased rates of forest plantation on wasteland, i.e., degraded lands, in southern India. Building on multidisciplinary field work and results from the model GCOMAP, the aim is to (1) identify and characterize the barriers to plantation activities in four agro-ecological zones in the state of Karnataka and (2) investigate what would be required to overcome these barriers and enhance the plantation rate and productivity. The results show that a rehabilitation of the wasteland based on plantation activities is not only possible but also anticipated by the local population and would lead to positive environmental and socio-economic effects at a local level. However, in many cases, the establishment of plantation activities is hindered by a lack of financial resources, low land productivity and water scarcity. Based on the model used and the results from the field work, it can be concluded that certified emission reductions such as carbon credits or other compensatory systems may help to overcome the financial barrier; however, the price needs to be significantly increased if these measures are to have any large-scale impact.  相似文献   
704.
Climate adaptation is a complex task surrounded by uncertainty. To support climate adaptation policies, a new scenario approach is pursued to explore possible discontinuous future developments of societal perspectives on climate adaptation issues. The scenario approach was tested for a case study on Dutch river management. In a series of scenario development workshops, a select group of stakeholders explored the perspectives on the management of the River Meuse in the past, present, and future. The process was supported by an analytical perspectives mapping tool to illustrate and analyze the development of perspectives over time. The process and analytical tools contributed to insight into the drivers of perspective change for the case study at hand. Moreover, the stakeholders highlighted the potential of the approach for water management policy for creating awareness about the plurality of perspectives and the dynamics of perspective change, monitoring perspectives and perspective change as part of a flexible policy approach, and anticipating on the occurrence of shock events. Further work is required to better represent the social dynamics of perspectives change, to better empirically ground the perspective change model, and to apply integrated water models in the scenario development process to assess water–society interactions.  相似文献   
705.
The states of the populations of five dominant species of predatory mammals living in the area affected by the Kalinin Nuclear Power Plant (NPP) and in remote districts of Tver’ oblast have been compared. A total of 1120 skulls, including 708 skulls from the vicinity of the NPP, have been examined. The data on parameters characterizing similarities between the samples, the degree and structure of intrapopulation diversity, and ontogenetic stability suggest with a high probability that the Kalinin NPP has no effect on wild populations of predatory mammals.  相似文献   
706.
Molecular genetic methods were used to perform the species and individual identification of 117 samples of hair and feces of carnivores collected in natural habitats. The species were identified for 85.5% of the samples. The analysis of the nucleotide sequences of the cytochrome b mitochondrial gene was used to identify the samples of hair and feces of snow leopards (Uncia uncia, 40%), red foxes (Vulpes vulpes, 48%), wolves (Canis lupus, 6%), and lynx (Lynx lynx, 5%). The analysis of eight microsatellite loci allowed the genotypes of 13 snow leopards to be described. The sex of 11 animals was identified.  相似文献   
707.
The results of studies on the radial increment of larch and pine in central Yakutia are presented. The application of dendroclimatological methods to the study of tree-ring chronologies has made it possible to evaluate tree growth response to the dynamics of climatic factors over the past 120 years. The results of analysis of radial tree increment show that the onset of the growing season has shifted to earlier dates by the end of the 20th century.  相似文献   
708.
The purpose of this paper is to study the redistribution of chemical species (OH, HO2, H2O2, HNO3 and H2SO4) over West Africa, where the cloud cover is ubiquitously present, and where deep convection often develops. In this area, because of these cloud systems, chemical species are redistributed by the ascending and descending flow, or leached if they are soluble. So, we carry out a mesoscale study using the Regional Atmospheric Modelling System (RAMS) coupled to a code of gas and aqueous chemistry (RAMS_Chemistry). It takes into account all processes under mesh. We examine several cases following the period (November and July), with inputs emissions (anthropogenic, biogenic and biomass burning). The radicals OH and HO2 are an indicator of possibilities for chemical activity. They characterize the oxidizing power of the atmosphere and are very strong oxidants. The acids HNO3 and H2SO4 are interesting in their transformation into nitrates and sulfates in precipitation. In November, when photochemistry is active during an event of biomass burning, concentrations of chemical species are higher than those of November in the absence of biomass burning. The concentrations of nitric acid double and sulfuric acid increases 70 times. In addition, the concentrations are even lower in July if there is a deep convection. Compared to measures of the African Monsoon Multidisciplinary Analysis (AMMA), the results and observations of radicals OH and HO2 are the same order of magnitude. Emissions from biomass burning increase the concentrations of acid and peroxide, and a deep convection cloud allows the solubility and the washing out of species, reducing their concentration. Rainfalls play a major role in solubility and washing out acids, peroxides and radicals in this region.  相似文献   
709.
Synthesis and characterization of novel biodegradable, water soluble and optically active DL-malic acid (DMA) and citric acid (CA) copolymers were studied for possible use as antibacterial agents. The copolymers were synthesized by direct bulk melt condensation in the absence of a catalyst above 150 °C. Characterization of obtained copolymers was carried out with the help of infrared absorption spectra, differential scanning calorimetry and thermo gravimetric analysis. The antibacterial activity of copolymers against bacteria was investigated. The results obtained shows the above copolymers possess a broad wound dressing activity against different types of bacteria and may be useful as antibacterial agents.  相似文献   
710.
Environmental change is likely to have a strong impact on biodiversity, and many species may shift their distribution in response. In this study, we aimed at projecting the availability of suitable habitat for an endangered amphibian species, the Fire-bellied toad Bombina bombina, in Brandenburg (north-eastern Germany). We modelled a potential habitat distribution map based on (1) a database with 10,581 presence records for Bombina from the years 1990 to 2009, (2) current estimates for ecogeographical variables (EGVs) and (3) the future projection of these EGVs according to the statistical regional model, respectively, the soil and water integrated model, applying the maximum entropy approach (Maxent). By comparing current and potential future distributions, we evaluated the projected change in distribution of suitable habitats and identified the environmental variables most associated with habitat suitability that turned out to be climatic variables related to the hydrological cycle. Under the applied scenario, our results indicate increasing habitat suitability in many areas and an extended range of suitable habitats. However, even if the environmental conditions in Brandenburg may change as predicted, it is questionable whether the Fire-bellied toad will truly benefit, as dispersal abilities of amphibian species are limited and strongly influenced by anthropogenic disturbances, that is, intensive agriculture, habitat destruction and fragmentation. Furthermore, agronomic pressure is likely to increase on productive areas with fertile soils and high water retention capacities, indeed those areas suitable for B. bombina. All these changes may affect temporary pond hydrology as well as the reproductive success and breeding phenology of toads.  相似文献   
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