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飞行时间(TOF)筛查方式技术以其特有的优势,如全扫描数据采集、非预期化合物历史数据再查询等在环境监测领域的应用已经取得了稳步增长.满足全球食品需求,杀虫剂、除草剂和杀真菌剂使用泛滥.这些化学物质施用到庄稼上,将不可避免地污染土壤和河道.因此需要执行严格的环境监察,以保护环境、植物和野生动物  相似文献   
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A comparative study (June-July 2001) on zooplankton community structure amid polluted conditions in a stagnant harbour and relatively unaffected tidal estuary near Visakhapatnam, on the east coast of India, revealed a marked disparity in species composition and abundance. While the harbour supported a rich population of calanoids (46.4%), the estuary sustained mostly cyclopoids (55.2%). Univariate and multivariate techniques (species diversity, clustering, non-metric multi-dimensional scaling and one-way ANOSIM) revealed the existence of two differing zooplankton assemblages and associated water quality (similarity 50.6%). While the estuary is typified by high amounts of dissolved silica (67.4 ± 17.7 μmol l-1) linked with monsoon influx, the harbour waters revealed abnormal levels of phosphate (40.9 ± 9.2 μmol l-1) and nitrate (15.3 ± 5.41 μmol l- 1) suggestive of intense eutrophication, caused by the discharge of fertilizer-factory waste and domestic sewage. On the basis of routines (e.g. BVSTEP, SIMPER) implemented in Plymouth Routines in Multivariate Ecological Research, it was possible to demonstrate that while species such as Oithona rigida, Oithona brevicornis, crustacean nauplii, gastropod veligers, Acartia spinicauda, and Acartia centrura played a key role in discriminating the zooplankton assemblage in the estuary, Acrocalanus spp. (mainly Acrocalanus gracilis) played a keyed role in harbour waters. Canonical Correspondence Analysis revealed species-environment relationships; for example, while the distribution of Oithona spp. and its associates in the estuary corresponded intimately with high silicate, temperature, and low salinity, it was high salinity, phosphate, and nitrate in the harbour channel that supported a different assemblage of copepods dominated by calanoids.  相似文献   
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Background

Tests in pregnancy such as chromosomal microarray analysis and exome sequencing are increasing diagnostic yield for fetal structural anomalies, but have greater potential to result in uncertain findings. This systematic review investigated the experiences of prospective parents about receiving uncertain results from these tests.

Methods

A systematic search of three electronic databases was conducted. Data extraction was performed for studies that met the eligibility and quality criteria. Results were synthesised following the principles of thematic analysis.

Results

Fourteen studies (10 qualitative, 4 quantitative) were included. Findings were grouped into three overarching themes. Sources of uncertainty included the testing procedure, the diagnosis and prognosis, and health professionals' own uncertainty. The clinical impact of the uncertainty included parents struggling to make clinical decisions with the information available, the emotional impact included decisional-regret, shock, worry and feeling overwhelmed. To manage the uncertainty, parents sought support from healthcare professionals, friends, family, the internet and other parents as well as remaining hopeful.

Conclusions

Prospective parents experience a myriad of uncertainties in the prenatal setting, which must be handled sensitively. Future research should explore optimal ways of managing uncertainty to minimise harm. Recommendations are made for discussing uncertainty during pre- and post-test counseling.  相似文献   
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We have investigated the filtering effects of three types of air control systems of enclosed structures on viable particles in the ambient air. Aspergillus fumigatus and other thermophilic organisms were used as monitors for viable particles. The indoor concentrations of viable particles were found to be affected by building design and the use of conventional mechanical air systems. Viable particles of approximately 4.0 μm and greater in aerodynamic diameter were filtered from the air while respirable size particles less than 4.0 μm were not filtered as well. There was evidence of growth of viable particles within the mechanical air systems. Conventional air control systems may not be adequate for the control of viable particle contamination of the indoor environment without modifications and proper maintenance.  相似文献   
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Declining biodiversity in protected areas in Laos is attributed to unsustainable exploitation of natural resources. At a basic level, an important need is to develop capacity in academic and professional training institutions to provide relevant training to conservation professionals. The paper (a) describes the capacity building approach undertaken to achieve this goal, (b) evaluates the effectiveness of the approach in building capacity for implementing conservation and (c) reviews implementation outcomes. Strong linkages between organizations implementing field conservation, professional training institutions, and relevant Government agencies are central to enhancing effectiveness of capacity building initiatives aimed at improving the practice of conservation. Protected area management technical capacity needs will need to directly influence curriculum design to insure both relevance and effectiveness of training in improving protected area management. Sustainability of capacity building initiatives is largely dependent on the level of interest and commitment by host-country institutions within a supportive Government policy framework in addition to engagement of organizations implementing conservation.  相似文献   
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