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1.
While innovations have fostered the mass production of food at low costs, there are externalities or side effects associated with high-volume food processing. We focus on foodborne illness linked to two commodities: ground beef and bagged salad greens. In our analysis, we draw from the concepts of risk, reflexive modernization, and techniques of ethical neutralization. For each commodity, we find that systems organized for industrial goals overlook how production models foster cross-contamination and widespread outbreaks. Responses to outbreaks tend to rely on technological fixes, which do not constitute the reflexive change needed to holistically and effectively address foodborne illness in the long term. We contend that powerful anti-reflexivity movements resist calls for reform and successfully maintain industrial goals and organization. Actions that thwart changes in agrifood systems to better protect consumers are unethical, yet they continue to be successful. We argue that specific techniques of ethical neutralization play an important part in their success. Research on anti-reflexivity and techniques of neutralization will serve to further expose the ethical issues associated with the industrial agrifood system and foster new guiding principles and organizational designs for food production.  相似文献   

2.
The brain's reward systems reinforce behaviors required for species survival, including sex, food consumption, and social interaction. Drugs of abuse co-opt these neural pathways, which can lead to addiction. Here, we used Drosophila melanogaster to investigate the relationship between natural and drug rewards. In males, mating increased, whereas sexual deprivation reduced, neuropeptide F (NPF) levels. Activation or inhibition of the NPF system in turn reduced or enhanced ethanol preference. These results thus link sexual experience, NPF system activity, and ethanol consumption. Artificial activation of NPF neurons was in itself rewarding and precluded the ability of ethanol to act as a reward. We propose that activity of the NPF-NPF receptor axis represents the state of the fly reward system and modifies behavior accordingly.  相似文献   

3.
Leptin, a hormone secreted by fat cells, suppresses food intake and promotes weight loss. To assess the action of this hormone on brain reward circuitry, changes in the rewarding effect of lateral hypothalamic stimulation were measured after leptin administration. At five stimulation sites near the fornix, the effectiveness of the rewarding electrical stimulation was enhanced by chronic food restriction and attenuated by intracerebroventricular infusion of leptin. In contrast, the rewarding effect of stimulating neighboring sites was insensitive to chronic food restriction and was enhanced by leptin in three of four cases. These opposing effects of leptin may mirror complementary changes in the rewarding effects of feeding and of competing behaviors.  相似文献   

4.
行政奖励是随着现代市场经济和民主政治的深入发展而勃兴的一种新型非强制行政模式。但是,长期以来受传统行政理论和观念的影响,行政奖励在立法、执法、法学研究中不受重视,导致在社会实践中频现弊丑,产生了严重的负效应,其法治水平亟需提高。本文就我国行政奖励制度存在的主要问题和如何完善进行思考,提出了自己的看法和建议。  相似文献   

5.
The crystal structure of the red picric acid salt of serotonin was determined by x-ray diffraction methods. The structure consists of parallel hydroxyindole and picrate planes which are intimately stacked with an interplanar separation of 3.3 to 3.4 angstroms. The stacking interaction appears to be of the donor-acceptor (charge-transfer) type, involving specific contacts between picrate nitro groups and atoms of the hydroxyindole moieties. Similar interactions might mediate biological processes involving serotonin.  相似文献   

6.
The dopamine receptor blocker pimozide attenuated lever-pressing and running for food reward in hungry rats. In each case the characteristic behavior of pimozide-treated rats was the same as that of undrugged rats when reward was simply withheld. Drug-induced performance difficulties were ruled out by the presence of periods of normal responding in drug-treated animals. Pimozide appears to selectively blunt the rewarding impact of food and other hedonic stimuli.  相似文献   

7.
Hoch I 《Science (New York, N.Y.)》1976,193(4256):856-863
As cities increase in size, so do wage rates for the same work. There is evidence that the wage differential is persistent and stable over time, which suggests that the differential does not arise from a lack of adjustment that is in process of correction. Indeed, there is an inverse relation between size and growth rate. Large metropolitan areas with high wage rates have been losing population in recent years, which is hardly a sign that their higher wage rates are temporary inducements to workers to move into those cities. It is much more plausible that the differential is a more-orless permanent money payment that compensates urban residents for costs they bear as population size increases. This argument does not deny that there are nonwage benefits as well as costs of city size, that city size effects may vary between individuals and groups, or that there may be scope for improved policy on population distribution. Nonetheless, the benefits of size seem to be outweighed by the costs; all types and groups of people generally can and do move about until alternative locations are less attractive than their current location; and solutions to population distribution problems will often emerge as byproducts to the solutions of more basic problems.  相似文献   

8.
Stronger collaboration between government organizations (GOs), NGOs, and rural people has long been advocated as a means of enhancing the responsiveness, efficiency, and accountability of GOs and NGOs. This paper reviews the arguments and evidence for specific types of collaboration for sustainable agricultural development, setting it into the context of Korten's (1980) concept of “learning process.” Taking recent examples from Udaipur District in India, it reviews the experiences and potential of collaboration, arguing that, while informal interaction increases and enriches the fabric of pluralist development, certain strategic decisions often require a degree of formality. These include decisions on the development of human resources — here both the users and providers of services. Moreover, human resource development (HRD) must be viewed in the context of the mandates, aspirations, and systems of accountability and rewards of the institutions concerned. These determine whether institutions develop and expand their own human resources or draw upon those of others by collaborating with them. Individuals engaged in these organizations can be more effectively induced to collaborate with others by combinations of flexibility and appropriate reward systems than they can be forced to do so by instructions or commands. Several conclusions follow: decisions to act together are unlikely to progress unless translated into concrete actions; authority to take local-level decisions in GOs needs strengthening if they are to provide the necessary flexibility; and, although collaboration should in principle be built on the comparative advantage of different types of organization, in practice, each will have to incorporate the skills of the other, at least to some level, if they are to communicate effectively. NGOs and GOs must also enhance their understanding of farmers' ability to make demands on external organizations. Edging towards collaboration is a delicate and painstaking process. Only if many of the above conditions are given due priority will early examples have something to offer to the numerous NGOs, GOs and international agencies wishing to learn from them.  相似文献   

9.
Instrumental conditioning studies how animals and humans choose actions appropriate to the affective structure of an environment. According to recent reinforcement learning models, two distinct components are involved: a "critic," which learns to predict future reward, and an "actor," which maintains information about the rewarding outcomes of actions to enable better ones to be chosen more frequently. We scanned human participants with functional magnetic resonance imaging while they engaged in instrumental conditioning. Our results suggest partly dissociable contributions of the ventral and dorsal striatum, with the former corresponding to the critic and the latter corresponding to the actor.  相似文献   

10.
Using a household survey data collected from four leading maize producing provinces in China,this paper studies the decisions of maize farmers on seed choices and variety portfolios when asymmetrical information exists in the market.Our findings indicate,while farmers generally tend to adopt new varieties with the expectation of potential higher yield,the primary driver to do so for those who have less information on seed varieties is to reduce production risk.Improving seed market management and providing more seed information to farmers would be beneficial in choosing seed varieties and maize production.  相似文献   

11.
We take advantage of our knowledge of the neural circuitry of reward to investigate a puzzling economic phenomenon: Why do people overbid in auctions? Using functional magnetic resonance imaging (fMRI), we observed that the social competition inherent in an auction results in a more pronounced blood oxygen level-dependent (BOLD) response to loss in the striatum, with greater overbidding correlated with the magnitude of this response. Leveraging these neuroimaging results, we design a behavioral experiment that demonstrates that framing an experimental auction to emphasize loss increases overbidding. These results highlight a role for the contemplation of loss in understanding the tendency to bid "too high." Current economic theories suggest overbidding may result from either "joy of winning" or risk aversion. By combining neuroeconomic and behavioral economic techniques, we find that another factor, namely loss contemplation in a social context, may mediate overbidding in auctions.  相似文献   

12.
The frontopolar cortex (FPC), the most anterior part of the frontal lobes, forms the apex of the executive system underlying decision-making. Here, we review empirical evidence showing that the FPC function enables contingent interposition of two concurrent behavioral plans or mental tasks according to respective reward expectations, overcoming the serial constraint that bears upon the control of task execution in the prefrontal cortex. This function is mechanistically explained by interactions between FPC and neighboring prefrontal regions. However, its capacity appears highly limited, which suggests that the FPC is efficient for protecting the execution of long-term mental plans from immediate environmental demands and for generating new, possibly more rewarding, behavioral or cognitive sequences, rather than for complex decision-making and reasoning.  相似文献   

13.
Thirsty rodents will persistently lick a stream of dry air pumped through a standard drinking tube. This air-licking is attenuated by experimental manipulations which reduce the evaporative cooling of the tongue and mouth produced by the airstream. This suggests that such cooling is itself an effective reward for thirstry rodents. We tested this hypothesis by presenting thirsty rodents with a piece of cold, dry metal. Different species spent from 9 to 40 percent of their session time licking the cold metal. When deprived of water hamsters reared from birth without access to drinking water licked cold metal in preference to metal maintained at room or body temperature. This preference was approximately equal to that of littermates reared normally. We conclude that tongue cooling is a primary reward for thirsty rodents.  相似文献   

14.
Phosphorus-32 applied to leaves of Plantago erecta in a serpentine annual grassland reached the shoots of about 20 percent of the close neighbors. Vesicular-arbuscular mycorrhizae connect the root systems of neighbors of different species and probably mediate nutrient transfers among them. Spatial patterns of transfer show that taxonomic affinity, distance from donor, and size of recipient do not serve as predictors of transfer and that models of transfer by simple diffusion are not appropriate. No alternative predictor was discovered. The results underscore the importance of belowground interactions in explaining neighbor effects, but the factors controlling nutrient transfer and its consequences for community structure appear complex.  相似文献   

15.
Injection of norepinephrine in the lateral ventricles of rats recovering from lateral hypothalamic anorexia caused immediate feeding and, frequently, overeating. Intraventricular administration of the alpha-noradrenergic blocker, phentolamine, suppressed feeding in both normal rats and rats that had recovered from lateral hypothalamic lesions. Feeding is reinforced by ascending medial forebrain bundle fibers that form alpha-noradrenergic synapses in the hypothalamus and forebrain. Damage to these fibers suppresses feeding by reducing noradrenergic transmission and, hence, the rewarding value of food. Recovery of feeding after hypothalamic lesions coincides with the recovery of noradrenergic reward function.  相似文献   

16.
西周赏赐类铭文中常记载各种赏赐物品,这些赏赐物的出现以及之间的组合都呈现出一定规律。掌握这些规律不仅有助于正确理解铭辞文意,对充分认识西周赏赐制度,以及受赐者地位和判断铭文时代等也具有重要意义。此外,量化分析为考察这些规律提供了新的研究视角,进而以分析结果为基础探讨、总结各类赏赐物间组合规律。  相似文献   

17.
18.
The failure to find positive contrast effects in the runway may be attributed to a ceiling effect that can be overcome with the use of delay of reward. Rats were trained one trial a day in a runway with small, medium, or large reward. When a shift to large reward was combined with delay of reward, shift groups slowed down less than controls.  相似文献   

19.
拒腐防变重在把握自我。法律的制约,制度的约束,群众的监督,这是拒腐防变的外部监控机制。然而,共产党员如果忽视自身世界观的改造,摆不正自己的位子,不能正确行使权力,在金钱、美女诱惑下就可能企图超越法律、摆脱监督、挺而走险,最终走上犯罪的道路。因此,要正确地认识自己,自觉地接受监督,把握人生航向,抵制各种腐朽思想的侵蚀,洁身自好,这是世界观改造的最基木要求。堤防首先要从自己的思想和行为筑起,才能立于不败之地。在当今物欲横流的社会,共产党员更要经得起各种环境的考验。  相似文献   

20.
计算机房供电系统的负载主要有 2种:容性负载和感性负载,前一种为主要负载.现计算机主机及外设均采用偏容性负载的无工频变压器开关电源.由于容性负载对供电系统的开关、中线有特殊要求,为了保证计算机系统长期、可靠地运行以及机房的安全,本文介绍了计算机房供电系统的合理布线和维护方法.  相似文献   

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