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161.
Plastic is a broad name given to the different types of organic polymers having high molecular weight and is commonly derived from different petrochemicals. Plastics are generally not biodegradable or few are degradable but in a very slow rate. Day by day, the global demand of these polymers is sharply increasing; however, considering their abundance and potentiality in causing different environmental hazards, there is a great concern in the possible methods of degradation of plastics. Recently, there have been some debates at the world stage about the potential degradation procedures of these synthetic polymers and microbial degradation has emerged as one of the potential alternative ways of degradation of plastics. Alternatively, some scientists have also reported many adverse effects of these polymers in human health, and thus, there is an immediate need of a potential screening of some potential microbes to degrade these synthetic polymers. In this review, we have taken an attempt to accumulate all information regarding the chemical nature along with some potential microbes and their enzymatic nature of biodegradation of plastics along with some key factors that affect their biodegradability.  相似文献   
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Aboriginal land managers have observed that feral Asian water buffalo (Bubalis bubalis Lydekker) are threatening the ecological and cultural integrity of perennial freshwater sources in Arnhem Land, Australia. Here we present collaborative research between the Aboriginal Rangers from Warddeken Land Management Limited and Western scientists which quantified the ground-level impacts of buffalo on seven perennial freshwater springs of the Arnhem Plateau. A secondary aim was to build the capacity of Aboriginal Rangers to self-monitor and evaluate the ecological outcomes of their land management activities. Sites with high buffalo abundance had significantly different ground, ground cover, and water quality attributes compared to sites with low buffalo abundance. The low buffalo abundance sites were characterized by tall herbaceous vegetation and flat ground, whereas wallows, bare ground, and short ungrazed grasses were indicators of sites with high buffalo abundance. Water turbidity was greater when buffalo abundance was high. The newly acquired monitoring skills and derived indicators of buffalo damage will be used by Aboriginal Rangers to assess the ecological outcomes of their future buffalo control efforts on the Arnhem Plateau.  相似文献   
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The Vancouver Region is widely recognised as one North American jurisdiction where strong growth management plans and policies have been put in place in order to control urban sprawl. While many authors have lauded the region for its good planning intentions, there has been little in the way of assessment of actual performance. This paper attempts to identify some quantitative growth management goals that have been (officially and unofficially) espoused by planning authorities in the region, and to measure these against actual trends. The results are mixed: on the one hand, some key growth management goals adopted by the region are not ambitious compared with existing trends and even these goals are not being met. For instance, the supposedly compact scenario adopted by the region deviates hardly at all from existing growth trends, which regional planners had clearly identified as untenable and requiring drastic change. On the other hand, the region's goal of preserving extensive green areas has been achieved without being watered down during goal formulation or implementation. Whereas these findings may appear contradictory, they are not: conservation in the region has not compromised the potential for growth in the region—at least for the time being. The real test of regional growth management efforts will come in the near future when further expansion meets the 'green wall' on the periphery and NIMBY resistance against densification within existing urban areas. The study suggests that the current structure of regional planning, relying on a partnership between municipal and regional governments, has served the region fairly well in building support for the need for growth management and in elaborating growth management vision. However, there is serious doubt about the ability of this system to set ambitious growth management objectives and to see through the implementation of those objectives in the face of social forces attempting to preserve business-as-usual trends in the region.  相似文献   
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Information helps decision makers to address and to decide about environmental problems. In the context of climate change adaptation, often knowledge is missing on how the available information from impact models affects the decision-making process. The main aim of this study was to explore the extent of ambiguity and how new climate change information influenced decision of forest planners. We investigated changes in decisions of planners about forestry actions representing species choice and forest tourism and expiry dates of these actions leading to environmental constraints in the provision of ecosystem services. Forest planners evaluated expiry dates using four forest ecosystem services: forest production, stand yield class, sequestered carbon, and potential tourism. Data were collected during workshops with eleven forest planners from three forest districts in Scotland. Presented climate change information modified the understanding and frames of planners about forestry actions assessed with accompanying expiry dates. Changes in the frames of planners often result in both earlier and later expiry dates. Ambiguity of planners was found to be dependent on diversity in frames and difficulty in evaluating multiple ecosystem services. These findings imply that due to ambiguity forest planners might find it hard to choose climate change adaptation measures and researchers can struggle to convince planners with new research findings.  相似文献   
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Polyetheramide(PEtA) resin was synthesized by the condensation polymerization of N,N-bis(2-hydroxy ethyl) linseed oil fatty amide diol (HELA) with resorcinol. It was further treated with different percentage of toluylene 2-4-diisocyanate (TDI) to obtain the urethane modified polyetheramide resins (UPEtA). The structural elucidation of PEtA and urethane modified polyetheramide(UPEtA) were carried out by FT-IR, 1H-NMR and 13C-NMR spectroscopic techniques. These analyses confirm the formation of PEtA and UPEtA. Physico-chemical and physico-mechanical analysis were performed by standard laboratory methods. The resin composition UPEtA-24 showed best physico-mechanical properties with scratch hardness 2.0 kg, impact resistance 150 lb/in. and good bending ability. The thermal stability and curing behavior of polymers were respectively studied by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). Thermal analysis shows that these coatings can be used safely upto 190 °C. The coatings of UPEtA resins were prepared on mild steel strips. The anticorrosive behavior of UPEtA coatings were investigated in acid, alkali, water and xylene. All the coatings exhibit good chemical resistance performance in acid, alkali, saline and organic solvents, while the resin UPEtA-24 shows the best performance.  相似文献   
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Technology transfer is a significant effort of the federal government and the intent of this effort is to transfer technologies developed in federal laboratories to the private sector for commercial use. The Federal Laboratory Consortium for Technology Transfer is a clearing-house for technologies developed through federal research laboratories. In addition, universities and other institutions use various mechanisms for transferring the technologies or knowledge to the private sector for civilian use. In this paper, the transfer of experimental and conceptual knowledge from research environment to civilian sector, covering aspects of engineering and social science is emphasized. The engineering examples deal with alleviating the nitrate pollution of rural domestic wells (a conceptual knowledge) and phytoremediation of hazardous wastes (an experimental knowledge). The social science examples deal with a culture assimilator for improving race relations (a conceptual knowledge) and a multimedia assimilator for global managers (an experimental knowledge). In each case, mechanisms and shortcomings involved in transfer-ring the knowledge for civilian use are demonstrated. We present a framework for knowledge transfer, and discuss the role of champions in knowledge transfer. We take the position that, though the attributes of the technology itself are important, knowledge transfer does require champions.  相似文献   
170.
An Erratum has been published for this article in Prenatal Diagnosis 22 (5) 2002, 451. Preimplantation genetic diagnosis (PGD) requires the combined efforts of geneticists and workers in the field of reproductive medicine. This was studied on the basis of a questionnaire, sent to 35 members of the PGD Consortium of the European Society of Human Reproduction and Embryology (ESHRE). A reply was obtained from 20 centres. They represent the majority of activities in the field of PGD in the world. It is obvious that many of the activities (in vitro fertilisation, embryo culture and biopsy) take place in IVF units while others (counselling and diagnosis) are the responsibility of genetic diagnostic centres. The distances between both units vary considerably. In all but one centre sex determination is offered. Aneuploidy screening is offered in 13 out of 20 centres. PGD of translocations and other structural chromosome abnormalities is offered in all but one centre. The number of monogenic diseases offered varies considerably. In comparison to prenatal diagnosis PGD is more expensive. The majority of these costs are due to the IVF or ICSI procedure. The charges for PGD vary between about € 600 and € 4000. In 16 out of 20 centres the parents to be must sign an informed consent form. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
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