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81.
Environmental Science and Pollution Research - In this study, the simultaneous degradation of antibiotics (ampicillin, sulfamethazine, and tetracycline; and non-steroidal anti-inflammatories...  相似文献   
82.
Food and Environmental Virology - The experience of COVID19 pandemic has demonstrated the real concern of biological agents dispersed in the air and surfaces environments. Therefore, the need of a...  相似文献   
83.
For more than half a century, research and practice in international development has focused on improving the quality of life of people living in developing regions of the world. Recently, researchers, practitioners, and policy makers have recognized the need to blend insights from experts and community stakeholders in development decisions. Research in the decision sciences tells us that these kinds of multiparty and multiattribute decisions are extremely challenging. However, recent experience using structured decision-making (SDM) approaches suggests that the quality of both expert and stakeholder input, and resulting decisions, can be improved by ensuring that people address a series of basic principles relating to identifying objectives and their associated attributes, estimating the consequences of proposed actions, and directly confronting trade-offs that arise during the evaluation of management alternatives. In this paper, we provide an overview of SDM and then discuss a research initiative aimed at applying the approach to a pressing international development problem in rural Costa Rica: management of the lucrative but also environmentally destructive pineapple industry. The objectives of this research were twofold: First, we sought to help inform policy decisions by eliciting land management preferences regarding the pineapple industry from people living in communities surrounding plantations. Second, we evaluated the effectiveness of the SDM approach in a developing community context.  相似文献   
84.
Carbon paste electrodes (CPEs) modified with a biosolid, two types of soils with different amounts of organic matter (OM), and two biocomposites (soils mixed with a biosolid) were used to assess and compare the Cu(II) ion retention properties of the organic matter contained in the samples. The accumulation of Cu(II) on the surface of the modified carbon paste electrodes (MCPEs) was performed under open-circuit conditions. When comparing the response of the MCPEs while assessing parameters such as pH, preconcentration time, and adsorption/desorption capacity, it was found that the reaction mechanism of the two soils is different between the soils and dissimilar from the biosolid; while the biocomposites show reaction mechanisms that are intermediate between those of the soils and the biosolid. This was proven with the use of infrared spectroscopy, since the FTIR spectra show similarities between the two soils and significant differences between the soils and the biosolid.  相似文献   
85.
The Argentine Pampas, one of the main agricultural areas in the world, recently has undergone significant changes in land use and structural characteristics of agricultural production systems. Concerns about the environmental and societal impacts of the changes motivated development of an agent-based model (ABM) to gain insight on processes underlying recent observed patterns. The model is described following a standard protocol (ODD). Results are discussed for an initial set of simplified simulations performed to understand the processes that generated and magnified the changes in the Pampas. Changes in the structure of agricultural production and land tenure seem to be driven by differences among farmers’ ability to generate sufficient agricultural income to remain in business. In turn, as no off-farm or credit is modeled, economic sustainability is tied to initial resource endowment (area cropped). Farmers operating small areas are economically unviable and must lease out their farms to farmers operating larger areas. This leads to two patterns: (a) a concentration of production (fewer farmers operating larger areas) and, (b) an increase in the area operated by tenants. The simulations showed an increase of soybean area, linked to the higher profitability of this crop. Despite the stylized nature of initial simulations, all emerging patterns are highly consistent with changes observed in the Pampas.  相似文献   
86.
Ultraviolet (UV) spectroscopy is a valid surrogate for monitoring the formation of disinfection by-products (DBPs). Sodium thiosulphate is commonly used to remove disinfectant residual. However, it produces interferences with absorbance in the UV region. Relationship between trihalomethane (THM) formation and differential UV absorbance (−ΔA λ ) was explored in the presence of sodium thiosulphate. Chlorination of two synthetic and five natural waters was carried out. Sodium thiosulphate showed high UV absorption at 254 nm. This effect can be overcome selecting a higher wavelength. Optimum wavelength varied being about 290 nm for fulvic acid and 300 nm for humic acid type natural organic matter. Correlation between THMs formation and −ΔA λ was linear for all the analysed samples. Regression curves do not pass through zero indicating the existence of a threshold absorbance decreasment. Once it is surpassed THM release begins. Chlorination of surface waters showed that the presence of bromide significantly increases THMs vs. −ΔA λ slope. Furthermore, slope decreased with the aromaticity–hydrophobicity of organic matter.  相似文献   
87.
During the 1997–98 El Niño, Tumbes, Peru received 16 times the annual average rainfall. This study explores how Tumbes residents perceived the impact of the El Niño event on basic necessities, transport, health care, jobs and migration. Forty‐five individuals from five rural communities, some of which were isolated from the rest of Tumbes during the event, participated in five focus groups; six of these individuals constructed nutrition diaries. When asked about events in the past 20 years, participants identified the 1997–98 El Niño as a major negative event. The El Niño disaster situation induced a decrease in access to transport and health care and the rise in infectious diseases was swiftly contained. Residents needed more time to rebuild housing; recover agriculture, livestock and income stability; and return to eating sufficient animal protein. Although large‐scale assistance minimized effects of the disaster, residents needed more support. Residents' perspectives on their risk of flooding should be considered in generating effective assistance policies and programmes.  相似文献   
88.
Abstract

Metallic nanoparticles have emerged as an important class of nanomaterials for a wide range of industrial and medical applications. Because of the intensive commercial applications, risk assessment of these nanoparticles is of great importance. In the present study, the human hepatoma and leukemia cells were used to characterize the apoptotic effects of silver nanoparticles (4.7 and 42?nm) and gold nanoparticles (30?nm). Apoptotic cells were identified by chromatin condensation and flow cytometry analysis, using Annexin V/PI, TUNEL and caspase activation assays. Flow cytometry analysis showed that the three metallic nanoparticles induced apoptotic cell death in a concentration and time dependent-manner. Moreover, the three nanoparticles induced activation of caspase-3 and -7 in hepatoma and leukemia cells. Apoptotic effects were stronger after exposure of both cell lines with 4.7?nm silver nanoparticles than those obtained with 42?nm silver and 30?nm gold nanoparticles. In conclusion, silver (4.7 and 42?nm) and gold (30?nm) nanoparticles induced apoptosis in hepatoma and leukemia cells via the caspase dependent pathway. The smaller silver nanoparticles (4.7?nm) had a greater ability to induce apoptosis in both cell lines.  相似文献   
89.
Agave is a native plant utilized for mezcal and tequila production. Since 1997, Agave exploitation has been increasing, leading to possible ecological deterioration and without social and economic benefits for the rural population. A sustainability index was developed for 1990–2001, including social, economic and ecological indicators related to Agave exploitation at Zacatecas, Mexico. Increases in the rural population have had a negative effect on Agave sustainability, directly affecting the ecological component of sustainability. Increased Agave exploitation has not improved the socio-economic components and has negatively affected the ecological indicators. All these factors resulted in a low (= 0.6) sustainability index. A lack of appropriate management may have led to the exploitation of native plants, leading to ecological deterioration of the local plant populations, without contributing to socio-economic improvement for the human population. The model using the sustainability index may also be validated for other species within this region.  相似文献   
90.
The objective of this work is to examine to what degree the integration between R&D and environmental departments facilitates the achievement of an environmental practice-derived competitive advantage. With this aim, we surveyed 110 International Organization for Standardization (ISO) 14001 certified factories. The results reveal that the integration of environmental action into the R&D department enhances a company's reputation through the product quality and image. Moreover, the said integration positively influences the company's overall innovative capability and, hence, its ability to penetrate international markets.  相似文献   
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