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Given near unanimity in the environmental and industrial communities about the need for a new generation of environmental technology, the policy process unfortunately lags behind in moving toward this objective. This article examines causes and remedies for this gap in the context of American environmental policy. U.S. environmental laws continue to be pervaded by structural biases against new technology, and the complexity of their administration exacerbates the problem. Within the last few years, several important reform initiatives have arisen from inside the regulatory community; however, these can only go so far, given the current statutory framework Congress, too long quiescent, needs to become involved. A legislative reform package is proposed consisting of four main elements: a legislative mandate that makes promotion of technological innovation an explicit environmental objective; elimination of structural features in current law that impede innovation; creation of a new framework for standard-setting and enforcement that puts every firm on a trajectory toward environmental and technological improvement; and enlisting regulation as a "demand-pull" for environmentally superior technology.  相似文献   

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As sessile organisms, plants must adapt to their environment. One approach toward understanding this adaptation is to investigate environmental regulation of gene expression. Our focus is on the environmental regulation of EARLI1, which is activated by cold and long‐day photoperiods. Cold activation of EARLI1 in short‐day photoperiods is slow, requiring several hours at 4 °C to detect an increase in mRNA abundance. EARLI1 is not efficiently cold‐activated in etiolated seedlings, suggesting that photomorphogenesis is necessary for its cold activation. Cold activation of EARLI1 is inhibited in the presence of the calcium channel blocker lanthanum chloride or the calcium chelator EGTA. Addition of the calcium ionophore Bay K8644 results in cold‐independent activation of EARLI1. These data suggest that EARLI1 is not an immediate target of the cold response, and that calcium flux affects its expression. EARLI1 is a putative secreted protein and has motifs found in lipid transfer proteins. Over‐expression of EARLI1 in transgenic plants results in reduced electrolyte leakage during freezing damage, suggesting that EARLI1 may affect membrane or cell wall stability in response to low temperature stress.  相似文献   

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Ptarmigan (Lagopus mutus) hunting has long traditions in Norway. It is often assumed that hunters are more consumptively and less conservation oriented than other recreational groups. Considering the large numbers of hunters and the popularity of the sport it is more likely that hunters value both consumptive and appreciative aspects and represent diversity in their concern for the environment. In this study we surveyed 2,717 ptarmigan hunters to examine environmental orientation, and the effects of environmental orientation on different management regulations. Results showed that environmental concern is a discriminating factor for how the hunters rate hunting goals, harvest regulation measures, and acceptance of protecting parts of the bird populations in refuges. Increasing environmental concern is positively correlated with higher acceptance of regulatory management actions aimed at preserving the resource. Socio-demographic variables had limited effect on the relationship between environmental concern and attitudes toward management. Small game management needs to balance consumptive and appreciative experience dimensions, and degree of environmental orientation may be an indicator of acceptance of management actions.  相似文献   

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Because living systems depend on their environment, the evolution of environmental adaptability is inseparable from the evolution of life itself (Pross 2003). In animals and humans, environmental adaptability extends further to adaptive behavior. It has recently emerged that individual adaptability depends on the interaction of adaptation mechanisms at diverse functional levels. This interaction enables the integration of genetic, epigenetic and environmental factors for coordinated regulation of adaptations. In this review, we first present the basis for the regulation of adaptation mechanisms across functional levels. We then focus on neuronal activity-regulated adaptation mechanisms that involve the regulation of genes, noncoding DNA (ncDNA), ncRNAs and proteins to change the structural and functional properties of neurons. Finally, we discuss a selection of these important neuronal activity-regulated molecules and their effects on brain structure and function and on behavior. Most of the evidence so far is based on sampling of animal tissue or post-mortem studies in humans. However, we also present techniques that combine genetic with behavioral and neurophysiological measures in humans (e.g. genetic imaging) and discuss their potential and limitations. We argue that we need to understand how neuronal activity-dependent adaptation mechanisms integrate genetic, epigenetic and experience-dependent signals in order to explain individual variations in behavior and cognitive performance.  相似文献   

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The subcellular localization of plasma membrane proteins, such as receptors and transporters, must be finely tuned so that they can be readily downregulated in response to environmental cues. Some of these membrane proteins are post-translationally modified by conjugation to ubiquitin, which is used as a molecular tag to commit them to the endocytic pathway and promote their subsequent delivery to the lysosomes for degradation. This ubiquitylation step, which is performed by so-called ubiquitin ligases (or E3), appears therefore as a critical event for endocytosis and is subject to many levels of regulation. In this review, we focus on the regulation of cargo ubiquitylation by accessory proteins, or “adaptors”, and discuss the various ways by which they promote the action of ubiquitin ligases toward their specific cargoes. Common features emerge on this mode of regulation, which is present from yeast to human, regardless of the type of ubiquitin ligase in charge of the ubiquitylation. Finally, because these adaptors represent an additional layer of specificity in the ubiquitylation cascade, and can themselves be subject to a complex regulation, they are essential actors in the fine-tuning of endocytosis.  相似文献   

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Poelwijk FJ  de Vos MG  Tans SJ 《Cell》2011,146(3):462-470
Cellular regulation is believed to evolve in response to environmental variability. However, this has been difficult to test directly. Here, we show that a gene regulation system evolves to the optimal regulatory response when challenged with variable environments. We engineered a genetic module subject to regulation by the lac repressor (LacI) in E.?coli, whose expression is beneficial in one environmental condition and detrimental in another. Measured tradeoffs in fitness between environments predict the competition between regulatory phenotypes. We show that regulatory evolution in adverse environments is delayed at specific boundaries in the phenotype space of the regulatory LacI protein. Once this constraint is relieved by mutation, adaptation proceeds toward the optimum, yielding LacI with an altered allosteric mechanism that enables an opposite response to its regulatory ligand IPTG. Our results indicate that regulatory evolution can be understood in terms of tradeoff optimization theory.  相似文献   

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The major neuronal post-translational modification of tubulin, polyglutamylation, can act as a molecular potentiometer to modulate microtubule-associated proteins (MAPs) binding as a function of the polyglutamyl chain length. The relative affinity of Tau, MAP2, and kinesin has been shown to be optimal for tubulin modified by approximately 3 glutamyl units. Using blot overlay assays, we have tested the ability of polyglutamylation to modulate the interaction of two other structural MAPs, MAP1A and MAP1B, with tubulin. MAP1A and MAP2 display distinct behavior in terms of tubulin binding; they do not compete with each other, even when the polyglutamyl chains of tubulin are removed, indicating that they have distinct binding sites on tubulin. Binding of MAP1A and MAP1B to tubulin is also controlled by polyglutamylation and, although the modulation of MAP1B binding resembles that of MAP2, we found that polyglutamylation can exert a different mode of regulation toward MAP1A. Interestingly, although the affinity of the other MAPs tested so far decreases sharply for tubulins carrying long polyglutamyl chains, the affinity of MAP1A for these tubulins is maintained at a significant level. This differential regulation exerted by polyglutamylation toward different MAPs might facilitate their selective recruitment into distinct microtubule populations, hence modulating their functional properties.  相似文献   

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By reanalysing inaccurately presented data of Kerr et al. (2006) , we refute their claims that area-corrected species richness of endemic Madagascan birds and mammals increases toward the Equator and is best explained by environmental factors, and that the rainforest mid-domain effect (MDE) Lees et al. (1999) demonstrated is artefactual.  相似文献   

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The pig industry is struggling with negative attitudes of people toward sow husbandry. To be able to respond to these attitudes, the pig industry first has to understand people’s attitudes. The first objective of this study was to determine the attitudes of Dutch people toward sow husbandry with regard to animals, humans, and the environment. The second objective was to group people based on their attitudes toward sow husbandry and determine and compare the socio-demographic characteristics of these groups. An online survey was conducted in the Netherlands and there were 1,607 respondents. On average, respondents had negative attitudes toward all issues defined in this study. The most negative attitudes were toward the effect on both animals and consumers of the use of antibiotics, the number of animals kept per square meter, the possibility for animals to go outside, food safety risks, public health risks, and environmental waste. The findings indicate the importance of considering all the issues identified in this study during the process of developing measures to improve people’s attitudes toward sow husbandry. Respondents could be divided into four clusters; each cluster represented different attitudes toward sow husbandry and had different socio-demographic characteristics. This makes it possible for the pig industry to assign people with specific socio-demographic characteristics to one of the clusters and predict their attitudes toward sow husbandry. Knowledge of these attitudes enables the pig industry to predict how different groups of people will respond to different animal welfare measures. Results of this study are therefore useful for the pig industry to help improve people’s attitudes toward sow husbandry.  相似文献   

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Lakes are a common water resource. This study analyzed residents’ concerns regarding their lake environments to help solve lake environmental problems. The study area comprised three lakes in Japan—Kasumigaura, Suwa, and Biwa—which have different tendencies to change in water quality. A sample of 1200 respondents was evenly distributed among the three lake regions. A questionnaire survey asked about respondents’ proximity to the lake, their concerns about the lakes’ uses and environments, their evaluations of the lakes, and their opinions regarding environmental improvements. The number of options chosen in response to the multiple-answer questions was used to measure the extent of concern. The results found that knowledge of the water environment, general environmental concerns, the amount of travel time to the lake, and the visiting interval were significantly related to concerns about the lake environment. The results of logistic regression analysis found that high environmental concerns positively influenced attitudes toward lake use. Ways to increase concerns for lake environmental problems and the relationship between concerns and attitudes toward solving lake environmental problems are discussed.  相似文献   

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Cybernetic modeling strives to uncover the inbuilt regulatory programs of biological systems and leverage them toward computational prediction of metabolic dynamics. Because of its focus on incorporating the global aims of metabolism, cybernetic modeling provides a systems-oriented approach for describing regulatory inputs and inferring the impact of regulation within biochemical networks. Combining cybernetic control laws with concepts from metabolic pathway analysis has culminated in a systematic strategy for constructing cybernetic models, which was previously lacking. The newly devised framework relies upon the simultaneous application of local controls that maximize the net flux through each elementary flux mode and global controls that modulate the activities of these modes to optimize the overall nutritional state of the cell. The modeling concepts are illustrated using a simple linear pathway and a larger network representing anaerobic E. coli central metabolism. The E. coli model successfully describes the metabolic shift that occurs upon deleting the pta-ackA operon that is responsible for fermentative acetate production. The model also furnishes predictions that are consistent with experimental results obtained from additional knockout strains as well as strains expressing heterologous genes. Because of the stabilizing influence of the included control variables, the resulting cybernetic models are more robust and reliable than their predecessors in simulating the network response to imposed genetic and environmental perturbations.  相似文献   

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As of 1 January 2006 all automotive OEMs (original equipment manufacturers) and component manufacturers operating within the European Union will need to comply with the End-of-Life Vehicle Directive (referred to hereafter as the EU ELV Directive). The EU ELV Directive compels all OEMs to take back and dismantle all motor vehicles for domestic use at the end of their useful lives. Each component part will then be either reused or recycled. To this end, the ultimate goal of the EU ELV Directive is that all motor vehicles for domestic use will have a reuse or recyclable content of 85% at the end of their useful lives, moving toward 95% by 2015. The burden of the EU ELV Directive falls on both the OEMs and their component manufacturers, forcing them to innovate and "design for disassembly." This being the case, it offers a unique real world example with which to test the Porter Hypothesis. Porter asserts that strict, correctly formulated environmental regulation can offer a firm secondary benefits through improved product design and the reduction of waste. This in turn allows the firm to offset the cost of compliance. Because the EU ELV Directive has been fashioned to force firms into a process of innovation and redesign, the magnitude of these so-called offsets can be judged. This article employs Rugman and Verbeke's 1998 strategic matrix of firm response to environmental regulation to examine qualitative details of the strategic response of automotive component manufacturers and OEMs in the United Kingdom to the demands of the directive to judge the volume of offsets generated. This analysis shows no support for the Porter Hypothesis and challenges the assumptions of Rugman and Verbeke's model.  相似文献   

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11beta-hydroxysteroid dehydrogenases (HSDs) interconvert active 11-hydroxy glucocorticoids (cortisol, corticosterone) and their inert 11-keto derivatives (cortisone, 11-dehydrocorticosterone). 11beta-HSD type 1 is a predominant reductase that regenerates active glucocorticoids in expressing cells, thus amplifying local glucocorticoid action, whereas 11beta-HSD type 2 catalyzes rapid dehydrogenation, potently inactivating intracellular glucocorticoids. Both isozymes thus regulate receptor activation by substrate availability. Spatial and temporal regulation of expression are important determinants of the physiological roles of 11beta-HSDs, with each isozyme exhibiting a distinct, tissue-restricted pattern together with dynamic regulation during development and in response to environmental challenges, including diet and stress. Transgenic approaches in the mouse have contributed significantly toward an understanding of the importance of these prereceptor regulatory mechanisms on corticosteroid receptor activity and have highlighted its potential relevance to human health and disease. Here we discuss current ideas of the physiological roles of 11beta-HSDs, with emphasis on the key contributions made by studies of 11beta-HSD gene manipulation in vivo.  相似文献   

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Glutathione peroxidase enzyme superfamily plays significant role in the elimination of reactive oxygen free radicals in the animals. Many characteristics of these proteins have been revealed already, but their regulation is still not known. Several data suggest that some environmental factors have certain regulatory effect, while others propose strict genetic regulation. In this report we present four different environmental induction models in which New Zealand white rabbits were used as experimental animals. In three models, free radical load of different origin, lipidperoxide load, application of a glutathione depletor or a prooxidant agent, was introduced. Beside these negative models a positive model was also constructed in which additive selenium was supplied. Glutathione peroxidase activity was measured in blood serum, erythrocyte haemolysate and liver. Reduced glutathione, and malondialdehyde concentration in the liver were also determined. According to the results, the established models are capable for analysing the enzyme activity x environmental interactions.  相似文献   

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Although business firms have improved their environmental performance, a variety of forces are pushing businesses toward adopting environmental management throughout the entire life cycle of their products and processes. In this article we discuss the information systems elements of an environmental management approach we call "life-cycle-oriented environmental management" (LCOEM).This approach requires the firm to manage the effects of its processes from the creation of inputs to the final disposal of outputs, that is, from cradle to grave. We present a framework of the classes of information systems needed, describe their use in an LCOEM setting and define their inter relationships. We conclude with a discussion of the implications of LCOEM information systems.  相似文献   

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