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951.

Purpose  

Besides classical organic pollutants and pesticides, pharmaceuticals and their residues have nowadays become recognized as relevant environmental contaminants. The risks of these chemicals for aquatic ecosystems are well known, but information about the pharmaca-plant interactions and metabolic pathways is scarce. Therefore, we investigate the process of uptake of acetaminophen (N-Acetyl-4-aminophenol) by Brassica juncea, drug-induced defense responses and detoxification mechanisms in different plant parts.  相似文献   
952.

Introduction  

Within the last decade, numerous studies have investigated the role of environmental history on tolerance to stress of many organisms. This study aims to assess if Manila clams Ruditapes philippinarum may react differently to cadmium exposure and trematode parasite infection (Himasthla elongata) depending on their origin and environmental history in Arcachon Bay (France).  相似文献   
953.

Background, aim, and scope  

Pharmaceuticals are emerging pollutants widely used in everyday urban activities which can be detected in surface, ground, and drinking waters. Their presence is derived from consumption of medicines, disposal of expired medications, release of treated and untreated urban effluents, and from the pharmaceutical industry. Their growing use has become an alarming environmental problem which potentially will become dangerous in the future. However, there is still a lack of knowledge about long-term effects in non-target organisms as well as for human health. Toxicity testing has indicated a relatively low acute toxicity to fish species, but no information is available on possible sublethal effects. This study provides data on the physiological pathways involved in the exposure of Atlantic salmon as representative test species to three pharmaceutical compounds found in ground, surface, and drinking waters based on the evaluation of the xenobiotic-induced impairment resulting in the activation and silencing of specific genes.  相似文献   
954.

Background, aim, and scope  

Over the years, organic pollution in the environment has aroused people’s concern worldwide, especially persistent organic pollutants (POPs). Particularly in developing countries, plenty of concentrated organic wastewaters treated noneffectively are discharged into aquatic environments from chemical, textile, paper-making, and other industries to seriously threaten the surface and drinking water. The conventional wastewater treatment techniques are often helpless due to high cost with multilevel processing. Adsorption as an efficient method is often applied to the treatment of wastewater. The aim of this work is to develop an eco-friendly and cost-effective wastewater-sorbing material with weak acidic pink red B (APRB) and calcium carbonate (CaCO3) by reusing highly concentrated dye wastewater.  相似文献   
955.
Wood is commonly used in residential combustion for heating purposes; however, it can be a major source of air pollutants, namely fine particles, volatile organic compounds and carbon monoxide. Since 2004, the PM10 daily limit value has been surpassed in Portugal, and the European Commission has stated that plans and programs must be designed in order to reduce these levels. In Portugal, 18% of PM10 emissions are due to residential wood combustion, which may deeply impact the PM10 levels in the atmosphere. The main aim of this study is to investigate the impact of residential wood combustion on the air quality in Portugal. The air quality modelling system MM5/CHIMERE was applied over Portugal for a winter month, for the following three scenarios: the reference scenario, considering the actual emissions of PM10; scenario 1, where residential wood combustion emissions are not considered; and scenario 2, which takes into account a complete conversion from traditional fireplaces to certified appliances (with a 90% reduction in PM emissions). The residential wood combustion contribution to PM10 air quality concentration values during January 2007 ranges from 0 to 14 μg m?3, with a mean contribution of 10 μg m?3 in the Lisboa area and 6 μg m?3 in the Porto region. Concerning the legislated values, the area where the daily average limit value (50 μg m?3) is exceeded decreases by 46% in the simulation when residential combustion is not considered. The modelling results for scenario 2 are not significantly different from those for scenario 1. In summary, the regulation of the residential wood combustion sector is as an effective way to reduce the PM10 levels in the atmosphere as regards air quality plans and programs.  相似文献   
956.
957.
People for the Ethical Treatment of Animals (PETA) called for a ban on mulesing in the Australian sheep industry in 2004. Mulesing is a surgical procedure that removes wool-bearing skin from the tail and breech area of sheep in order to prevent flystrike (cutaneous myiasis). Flystrike occurs when flies lay their eggs in soiled areas of wool on the sheep and can be fatal for the sheep host. PETA claimed that mulesing subjects sheep to unnecessary pain and suffering and took action against the Australian wool industry that resulted in a number of international clothing retailers choosing not to use Australian wool. Although the Australian sheep industry agreed to phase out mulesing in 2010, there is some uncertainty as to whether this deadline will be achieved. The changing social ethic towards animal welfare suggests that the way the Australian sheep industry manages the phase out of mulesing in 2010 is vital to its future survival and success. It is likely that if mulesing does not cease in 2010 there will be a negative market reaction to Australian wool and the risk of legislation to ban mulesing. To avoid losing control of its animal welfare strategy, the Australian sheep industry should ensure that mulesing is phased out in 2010 and endorse the animal welfare ethic underpinning this change. The industry should also educate farmers and other industry stakeholders in how the changing social ethic for animal welfare can create new market opportunities for wool.  相似文献   
958.
959.
In agricultural areas, the contamination of feedstuffs with molds and mycotoxins presents major environmental and health concerns. During cattle feeding, fungi and mycotoxins were monitored in corn silage, oilseed cakes and bioaerosols collected in Normandy. Most of the corn silages were found to be contaminated by deoxynivalenol (mean concentration: 1883 μg kg?1) while a few of oilseed cakes were contaminated by alternariol, fumonisin B1 or gliotoxin. In ambient bioaerosols, the values for fungi per cubic meter of air varied from 4.3 × 102 to 6.2 × 105 cfu m?3. Seasonal variations were observed with some species like Aspergillus fumigatus which significantly decreased between the 2 seasons (P = 0.0186) while the Penicillium roqueforti group significantly increased during the second season (P = 0.0156). In the personal bioaerosols, the values for fungi per cubic meter of air varied from 3.3 103 to 1.7 106 cfu m?3 and the number of A. fumigatus spores significantly decreased between the 2 seasons (P = 0.0488). Gliotoxin, an immunosuppressive mycotoxin, was quantified in 3 personal filters at 3.73 μg m?3, 1.09 μg m?3 and 2.97 μg m?3.  相似文献   
960.
Renewable energy is considered an indispensable basis of sustainable energy systems as electricity generation from renewable sources results in low emissions of greenhouse gases compared to fossil fuel based electricity and contributes to sustainable development. However, effective strategies and conducive institutional settings are needed for advancement of such clean electricity systems. Although Thailand, as a nation, has a huge potential for renewable energy utilization, its total amount of electricity generation from renewables is relatively small and could be enlarged substantially. Lack of policy mechanisms, institutional development and financing exist as major barriers for Thailand in this regard. Investigation of the nation’s current energy strategy implementation shows that relevant energy and development policies are at different stages of implementation and institutional settings are continuously evolving. This paper argues that further significant efforts could be made towards advancement of renewable electricity and thus achievement of energy sustainability in Thailand. Resource planning, effective policy and institutions, focussed planning for energy sustainability and implementation of the Clean Development Mechanism (CDM) under the Kyoto Protocol could facilitate further advancement of renewables for the nation.  相似文献   
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