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721.
Social science is becoming increasingly important in conservation, with more studies involving methodologies that collect data from and about people. Conservation science is a normative and applied discipline designed to support and inform management and practice. Poor research practice risks harming participants and, researchers, and can leave negative legacies. Often, those at the forefront of field-based research are early-career researchers, many of whom enter their first research experience ill-prepared for the ethical conundrums they may face. We draw on our own experiences as early-career researchers to illuminate how ethical challenges arise during conservation research that involves human participants. Specifically, we considered ethical review procedures, conflicts of values, and power relations, and devised broad recommendations on how to navigate ethical challenges when they arise during research. In particular, we recommend researchers apply reflexivity (i.e., thinking that allows researchers to recognize the effect researchers have on the research) to help navigate ethical challenges and encourage greater engagement with ethical review processes and the development of ethical guidelines for conservation research that involves human participants. Such guidelines must be accompanied by the integration of rigorous ethical training into conservation education. We believe our experiences are not uncommon and can be avoided and hope to spark discussion to contribute to a more socially just conservation.  相似文献   
722.
Environmental Science and Pollution Research - Organochlorine pesticides have generated public concern worldwide because of their toxicity to human health and the environment, even at low...  相似文献   
723.

The contamination of soils and water with copper (Cu) can compromise the crops production and quality. Fungicides containing Cu are widely and intensively used in viticulture contributing to environmental contamination and genotoxicity in Vitis vinifera L. Despite the difficulty in reproducing field conditions in the laboratory, hydroponic solutions enriched with Cu (1, 10, 25 and 50 μM) were used in forced V. vinifera cuttings to evaluate the DNA damage in leaves of four wine-producing varieties (‘Tinta Barroca’, ‘Tinto Cão’, ‘Malvasia Fina’ and ‘Viosinho’). Alkaline comet assay followed by fluorescence in situ hybridisation (Comet-FISH) was performed with the 45S ribosomal DNA (rDNA) and telomeric [(TTTAGGG)n] sequences as probes. This study aimed to evaluate the tolerance of the four varieties to different concentrations of Cu and to determine which genomic regions were more prone to DNA damage. The comet assay revealed comets of categories 0 to 4 in all varieties. The DNA damage increased significantly (p < 0.001) with the Cu concentration. ‘Tinto Cão’ appeared to be the most sensitive variety because it had the highest DNA damage increase in 50 μM Cu relative to the control. Comet-FISH was only performed on slides of the control and 50 μM Cu treatments. Comets of all varieties treated with 50 μM Cu showed rDNA hybridisation on the head, ‘halo’ and tail (category III), and their frequency was significantly higher than that of control. The frequency of category III comets hybridised with the telomeric probe was only significantly different from the control in ‘Malvasia Fina’ and ‘Tinta Barroca’. Comet-FISH revealed partial damage on rDNA and telomeric DNA in response to Cu but also in control, confirming the high sensitivity of these genomic regions to DNA fragmentation.

  相似文献   
724.
Many kinds of cosmetic products were analyzed to determine gross radioactivity. In this study, gross alpha/beta radioactivity concentrations in 51 cosmetic samples were determined. The examined cosmetic products consist of blusher, eye shadow, lipstick, nail polish, shampoo, hand cream, cellulite cream, baby powder, soap, and toothpaste. The gross alpha–beta activity concentrations were measured with a nuclear spectroscopic system which contains gas-flow proportional counters. The highest gross alpha/beta activity concentrations were found in eye shadow samples of 1.621Bq g?1 for alpha and 6.471Bq g?1 for beta. The total effective doses due to gross radioactivity for skin were calculated. Although the effective dose of eye shadow samples had the highest value, the effective doses due to gross radioactivity concentrations in this study were found to be lower than the radiological limits given by the authorities.  相似文献   
725.
Abstract

Activated carbons are well-known porous materials as an effective adsorbent used for the removal of emerging contaminants, such as herbicides, which are increasingly present in water bodies. Most water treatment plants, specially in Brazil, are unable to completely remove such contaminants by the conventional process and advanced treatment using activated carbons is required. The aim of this paper was to verify the influence of the activated carbons granulometry and specific surface area on the 2,4-dichlorophenoxyacetic acid (2,4-D) herbicide removal efficiency using distilled-deionized water and filtered water collected from a conventional Water Treatment Plant. Commercial activated carbons samples used in this work were obtained from two different manufacturers. Activated carbons were analyzed by the specific surface area, pore size and volume distribution, nuclear magnetic resonance, infrared and x-ray spectroscopy, moisture, volatile matter and ash contents. Batch adsorption isotherms experiments were used and performed by Langmuir and Freundlich models. Granular and powdered activated carbons removed over 99% of 2,4-D in distilled water and near to 99% using filtered water. The activated carbons evaluated in this work presented high performance and played a key role in water treatment by removing 2,4-D herbicide, ensuring the protection of human health and the ecosystem.  相似文献   
726.
The extraordinary population growth of certain ungulate species is increasingly a concern in agroforestry areas because overabundance may negatively affect natural environments and human livelihoods. However, society may have negative perceptions of killing wildlife to reduce their numbers and mitigate damage. We used an online survey that included a choice experiment to determine Spanish citizens’ (n = 190) preferences toward wildlife population control measures related to negative effects of ungulate overabundance (negative impacts on vegetation and other wildlife species and disease transmission to livestock) in 2 agroforestry national parks in Spain. We used latent-class and willingness-to-pay in space models to analyze survey results. Two percent of respondents thought a national park should have no human intervention even if lack of management may cause environmental degradation, whereas 95% of respondents favored efforts to reduce damage caused by overabundant ungulate species. We estimated human well-being losses of survey respondents when sustainable effects of deer overabundance on the environment became unsustainable effects and well-being gains when sustainable effects transitioned to no visible effects. We found that the type of wildlife-control program was a very relevant issue for the respondents; indirect control in which killing was avoided was the preferred action. Sixty-six percent of respondents agreed with the option of hunters paying for culling animals to reduce ungulate impacts rather than management cost coming out of taxes, whereas 19% of respondents were against this option and willing to pay for other solutions in national parks. Our results suggest that killing wildlife in national parks could be a socially acceptable tool to manage overabundance problems in certain contexts, but it could also generate social conflicts.  相似文献   
727.
Two kinds of regional disparities can be distinguished in Belgium. First there is the internationally well‐known dispute between Flanders and Wallonia. Secondly, there are large disparities within the regions. Three policy levels deal with these disparities: the (Flemish) regional level, the national government level and the EEC level. The purpose of this paper is to sketch the regional problems in Belgium, to analyse the policies that deal with them, to consider the co‐ordination problems between them and to shed some light on the public choice aspects of government interventions. It is concluded that regional policy in Belgium is a highly politicised affair. Furthermore public attention paid to regional policies has outgrown the importance of our regional disparities. Even other forms of micro‐economic policy are jeopardised by regional disparities and the resulting pressure.  相似文献   
728.
We describe a case in which a trisomic 22 placenta could be the cause of severe growth retardation in a chromosomally normal female fetus. At amniocentesis a mosaic 46,XX/ 47,XX, +22 was observed in amniotic fluid specimens sampled on two different occasions, while fetal blood from a diagnostic cordocentesis revealed a normal chromosome constitution. Postnatal studies showed the consistent presence of trisomic 22 cells in the placenta, while only normal metaphases were found in amnion, blood, and fibroblast cultures.  相似文献   
729.
This study reports on a primary succession on a beach plain on the Dutch Wadden island of Schiermonnikoog. Vegetation succession started in 1959 when a sand dike was constructed to prevent structural erosion of the area by storm floods. Since then the sandy beach behind the dike has been protected from the direct influence of the North Sea. Heavy storms in 1972, however, created a large gap in the dike which has remained open since. Occasional storm floods during winter penetrate deeply into the area and salt water can cover parts of the beach plain for several months. This had a pronounced impact on the vegetation. Vegetation maps for six different years and data from a permanent plot have been used to reconstruct vegetation succession over a 42-yr period. Certain parts of the area seem to have changed little, while others have developed a grassland or scrub cover. The heavy storms and associated processes such as sand blowing, intensive flooding and increased salinity have created a disturbance/stress gradient of progressive and regressive succession across the beach plain. In certain places the vegetation cover has repeatedly been destroyed and succession re-initiated. It is concluded that the different stages of succession and associated diversity of plant species only can persist through the maintenance of the natural dynamics of the area.  相似文献   
730.
Soil respiration rates of a clay-loam textured Acrisol under different uses (Atlantic forest, manioc, horticulture and pasture) from Rio de Janeiro State were measured. The relationship between carbon dioxide (CO2) emissions and soil physico-chemical properties were investigated. Rates of CO2 emission of two sites (Atlantic forest and horticulture) were also evaluated in different seasons in 1997 and 1998. In the forest site, monthly means of measured respiration rates showed good correlation with soil temperature in the range 19.6–24.1°C (r2 = 0.89). In the horticulture site, no change was observed with soil moisture alone, in the range 3.0–13.2 wt%. In the horticulture soil, even when the surface soil was very dry, respiration rates increased in the hot, wetter summer but remained higher than the mean flux from forest soil. The CO2 emission flux of the Acrisol under different use showed good correlation with soil temperature (r2 = 0.72) and moisture (r2 = 0.61).  相似文献   
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