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1.
This paper seeks to understand why multinationals prefer to launch a label specific to their own product and examines how reliable these product-specific eco-labels are. A new methodology is applied to assess the extent to which eco-labels live up to claims about their contribution to conservation and the sustainable use of agricultural biodiversity. Product-specific eco-labels are considered as industry self-regulation and all three regulatory stages are studied: the planning, implementation and outcome stage. There are major differences between the product specific eco-labels in the degree in which agrobiodiversity management is part of the normative labeling schemes. Although there are some problems of reliability, such as transparency in the implementation stage and the monitoring in the outcome stage, the degree of reliability of product-specific labels is comparable with eco-labels of international labeling families. The conclusion is that only one of the product-specific eco-labels examined here is reliable when examined in the light of all three stages. The main reason why multinationals establish a product-specific eco-label instead of adopting one from an existing labeling family is that they want to profile themselves as distinct from other companies. The unique character of a product-specific label creates a market opportunity for them.  相似文献   
2.
An analogue study involving two experiments was conducted to test the initial carryover effects of hypnosis, meditation, and relaxation upon self-reports of awareness. In the first experiment, concentrative meditators reported fewer nonsensorial events than controls. In the second experiment, concentrative meditators again reported fewer nonsensorial events, but covariate analysis and pretest/posttest comparisons revealed that it was the controls who had changed, increasing their nonsensorial reports. In addition, the relaxation group increased its reports of somatic awareness. Results were discussed in terms of the effects of performance demands and the possibility that meditation and hypnosis might be able to disinhibit awareness processes otherwise inhibited by normal daily routines.This article represents in part findings from a masters thesis completed at Appalachian State University, Donald L. Clark, Ph.D., Director, and a doctoral dissertation completed at The University of North Carolina at Chapel Hill, David P. Rogers, Ph.D., and George S. Welsh, Ph.D., Co-Directors. The research was supported in part by a Grant-in-Aid of Research from Sigma Xi, the Scientific Research Society, with additional monies from the Smith Fund for graduate research at the University of North Carolina. Thanks go to Michelle Batchelder, Elizabeth Barbee, Lisa Barboun, Susan Durham, Lee Earl, Elizabeth Evans, Pam Gilmore, Sally Hall, Willian Hatch, Anne Mahaffie, Sally Parker, Lee Pusser, Susan Roach, Jennifer Rosenbaum, Skip Salguerro, Jeannette Smith, Michael Smith, Sylvia Sutton, and Lourdes Vinuales for their help in conducting the second experiment, with special thanks also to Susan Woodard (Experiment 1) and Alisa Huffman and Melanie Thackston (Experiment 2) for their help in coding the data. Helpful comments were made by Arthur N. Wiens, Ruth G. Matarazzo, Mary Lawrence Cawthon, W. Grant Dahlstrom, and Aija Ozolins on earlier drafts of this article.  相似文献   
3.
This study investigates the neurophysiological basis of EEG feedback for patients with epilepsy. Brain areas are identified that become hemodynamically deactivated when epilepsy patients, trained in EEG self-regulation, generate positive slow cortical potentials (SCPs). Five patients were trained in producing positive SCPs, using a training protocol previously established to reduce seizure frequency in patients with drug refractory epilepsy. Patients attempted to produce positive SCP shifts in a functional magnetic resonance imaging (fMRI) scanner. Two patients were able to reliably produce positive SCP shifts. When these successful regulators were prompted to produce positive SCPs, blood oxygen level-dependent (BOLD) response indicated deactivation, in comparison to a control state, around the recording electrode, frontal lobe, and thalamus. Unsuccessful regulators’ BOLD response indicated no deactivation in cortical areas proximal to the active electrode. No thalamic deactivation was found in poor regulators. Decreased seizure frequency from SCP training may be the result of positively reinforced inhibition in cortical areas proximal to active electrode placement, the frontal cortex, and the thalamus.  相似文献   
4.
Rappaport's (1968) study of self-regulation in the Tsembaga Maring ecosystem is an important substantive contribution to human ecology. Rappaport hypothesized that the Maring pig festival cycle is the dominant mechanism by which the quality of the Tsembaga ecosystem is maintained. In this paper, we demonstrate that the pig festival cannot serve this function. Simulation models of the Tsembaga ecosystem show that a stable, self-regulating equilibrium of the kind proposed by Rappaport is highly dependent upon a carefully chosen set of parameters which do not represent the most accurate choice from the available data. In the simulation model of Rappaport's hypothesis constructed by Shantzis and Behrens, equilibrium depends upon fixed population growth rates that lead to regularly scheduled pig festivals, whose timing insures that a fixed rate of removal of Tsembaga individuals in warfare prevents net population growth. More realistic models uniformly suggest that the pig festival plays no essential role in ecosystem regulation. We conclude that the evidence provided does not support the hypothesis.  相似文献   
5.
Autophagy is a process in which a eukaryotic (but not prokaryotic) cell destroys its own components through the lysosomal machinery. This tightly regulated process is essential for normal cell growth, development, and homeostasis, serving to maintain a balance between synthesis and degradation, resulting in the recycling of cellular products. Here we try to expand the concept of autophagy and define it as a general mechanism of regulation encompassing various levels of the biosphere. Interestingly, one of the consequences of such an approach is that we must presume an existence of the autophagic processes in the prokaryotic domain.  相似文献   
6.
Procedures used for relaxation training can resolve or precipitate dysfunction in patients undergoing self-regulation treatments. The present article discusses the role of the clinician in administering relaxation training via thermal biofeedback and coping with unforeseen negative effects of treatment. A case illustration involving the biobehavioral treatment of chest pain is presented and discussed to remind the reader of the significance of the therapist's role in helping tailor treatment programs to unique responses of the individual patient. The case highlights the value of thorough case management and clinical formulation in the successful resolution of relaxation-induced leg pain.  相似文献   
7.
Functional magnetic resonance imaging (fMRI) measures the blood oxygen level-dependent (BOLD) signal related to neuronal activity. So far, this technique has been limited by time-consuming data analysis impeding on-line analysis. In particular, no brain-computer interface (BCI) was available which provided on-line feedback to learn physiological self-regulation of the BOLD signal. Recently, studies have shown that fMRI feedback is feasible and facilitates voluntary control of brain activity. Here we review these studies to make the fMRI feedback methodology accessible to a broader scientific community such as researchers concerned with functional brain imaging and the neurobiology of learning. Methodological and conceptual limitations were substantially reduced by artefact control, sensitivity improvements, real-time algorithms, and adapted experimental designs. Physiological self-regulation of the local BOLD response is a new paradigm for cognitive neuroscience to study brain plasticity and the functional relevance of regulated brain areas by modification of behaviour. Voluntary control of abnormal activity in circumscribed brain areas may even be applied as psychophysiological treatment.  相似文献   
8.
Nitrate reductase (NR), a committed enzyme in nitrate assimilation, involves generation of nitric oxide (NO) in plants. Here we show that the NR activity was significantly enhanced by the addition of NO donors sodium nitroprusside (SNP) and NONOate (diethylamine NONOate sodium) to the culturing solution, whereas it was decreased by NO scavenger 2-(4-carboxyphenyl)-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide (cPTIO). Interestingly, both NO gas and SNP directly enhanced but cPTIO inhibited the NR activities of crude enzyme extracts and purified NR enzyme. The cPTIO terminated the interaction between NR-generated NO and the NR itself. Furthermore, the NR protein content was not affected by the SNP treatment. The investigation of the partial reactions catalysed by purified NR using various electron donors and acceptors indicated that the haem and molybdenum centres in NR were the two sites activated by NO. The results suggest that the activation of NR activity by NO is regulated at the post-translational level, probably via a direct interaction mechanism. Accordingly, the concentration of nitrate both in leaves and roots was decreased after 2 weeks of cultivation with SNP. The present study identifies a new mechanism of NR regulation and nitrate assimilation, which provides important new insights into the complex regulation of N-metabolism in plants.  相似文献   
9.
Parameters k and L in the Von Bertalanffy equation and their derivatives =kL, = logk + 2logL; as well as slopes bL/t of the regression L=atb (t, years), relative increments (CI=[L2–L1]/L1), specific growth rates (Cv=InL2–InL1), growth characteristics (Clh = CvxL1) and growth constants (Clt=Cvx[t2 + t1]/2) were analyzed. A total of 121 bream Abramis brama stocks in the first 10 years of life were studied. At the same real growth rate (the average absolute linear annual increments, mm year–1) the values of k, L, , , bL/t, CI, Cv and Clt in different stocks vary within almost the whole range. The main reason is the natural process of growth self-regulation: the relation between the average body lengths in the first year (L1) and the relative growth rates (slopes bL/t) is negative (bL/t = exp[0.1183–0.0053L1], r=0.76). The above relation defines 4 principal types of the Ford-Walford lines. Thirty four percent of the stocks have rather steep slopes of the lines and even parallel the absolute slope of 45°, so the L values of these stocks have no biological significance. The authors recommend a simple and more precise, from a biological point of view, approach for comparing fish population growth rates.  相似文献   
10.
This paper is a result of a long-term study of the apical meristems of the Allium cepa L. seedlings against a background of naturally changing geomagnetic field. Multinuclear cells, large cells with large nuclei, and giant cells with giant nuclei were detected. Changes in cellular structures were revealed, and the time-course of this process was followed. Changes in the cellular structure of meristems were correlated with the fluctuations of magnetic field of the Earth. The experiments conducted with in vitro culture of apical meristems showed that the observed changes were regulated on the local level.  相似文献   
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