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1.
This paper aims to examine the extent to which human participants show higher resilience compared to computer agents in agent-based participatory experiments. We motivate and examine three types of resilient behaviour of farmers during a crisis or as response to competitive pressure: successful survival, loss-minimising farm exits, and path breaking respectively path creating growth strategies. Our experiments revealed that human decision makers recognised and exploited such resilient strategies in periods of crisis or under challenging circumstances in general better than myopic optimising agents, although they did not perform better on average. The reason can be seen in a substantial heterogeneity of human decision makers, for which we identified four categories: negligent gamblers, actors missing opportunities, solid farm managers and successful path breakers.  相似文献   

2.
In ‘Hard’ science, scientists correctly operate as the ‘guardians of certainty,’ using hypothesis testing formulations and value judgements about error rates and time discounting that make classical inferential methods appropriate. But these methods can neither generate most of the inputs needed by decision makers in their time frame, nor generate them in a form that allows them to be integrated into the decision in an analytically coherent and transparent way. The need for transparent accountability in public decision making under uncertainty and value conflict means the analytical coherence provided by the stochastic Bayesian decision analytic approach, drawing on the outputs of Bayesian science, is needed. If scientific researchers are to play the rôle they should be playing in informing value-based decision making, they need to see themselves also as ‘guardians of uncertainty,’ ensuring that the best possible current posterior distributions on relevant parameters are made available for decision making, irrespective of the state of the certainty-seeking research. The paper distinguishes the actors employing different technologies in terms of the focus of the technology (knowledge, values, choice); the ‘home base’ mode of their activity on the cognitive continuum of varying analysis-to-intuition ratios; and the underlying value judgements of the activity (especially error loss functions and time discount rates). Those who propose any principle of decision making other than the banal ‘Best Principle,’ including the ‘Precautionary Principle,’ are properly interpreted as advocates seeking to have their own value judgements and preferences regarding mode location apply. The task for accountable decision makers, and their supporting technologists, is to determine the best course of action under the universal conditions of uncertainty and value difference/conflict.  相似文献   

3.
Calls for accountability and ‘impactful’ research are fundamentally reshaping the academy, giving rise to a large, critical scholarship on neoliberal regimes of accountability and their pernicious effects. But these calls also animate other institutional forms and practices that have received less critical attention. These include new forms of science that promise accountability through interdisciplinarity, collaborating with stakeholders, and addressing real‐world problems. This article considers one example of such accountable science: human dimensions of climate change field research. This research endeavour has produced surprising results, including the uncritical adoption of controversial Euro‐American ideas about traditional Others. In exploring how this has come about, the article considers how theoretical and disciplinary diversity are managed within this arena, and the organizing logics that enable climate sciences and scientists to work together. We ultimately argue that accountable science – like other neoliberal modes of accountability – can produce outcomes for which no one can be held to account.  相似文献   

4.
Organisms prefer to make their own choices. However, emerging research from behavioral decision making sciences has demonstrated that there are boundaries to the preference for choice. Specifically, many decision makers find an extensive array of choice options to be aversive, often leading to negative emotional states and poor behavioral outcomes. This study examined the degree to which human participants discounted hypothetical rewards that were (a) delayed, (b) probabilistic, and (c) chosen from a large array of options. The present results suggest that the "paradox of choice" effect may be explained within a discounting model for individual patterns of decision making.  相似文献   

5.
Participants completed a questionnaire priming them to perceive themselves as either objective or biased, either before or after evaluating a young or old job applicant for a position linked to youthful stereotypes. Participants agreed that they were objective and tended to disagree that they were biased. Extending past research, both the objective and bias priming conditions led to an increase in age discrimination compared to the control condition. We also investigated whether equity norms reduced age discrimination, by manipulating the presence or absence of an equity statement reminding decision-makers of the legal prohibitions against discrimination “on the basis of age, disability, national or ethnic origin, race, religion, or sex.” The presence of equity norms increased enthusiasm for both young and old applicants when participants were not already primed to think of themselves as objective, but did not reduce age-based hiring discrimination. Equity norms had no effect when individuals thought of themselves as objective – they preferred the younger more than the older job applicant. However, the presence of equity norms did affect individuals’ perceptions of which factors were important to their hiring decisions, increasing the perceived importance of applicants’ expertise and decreasing the perceived importance of the applicants’ age. The results suggest that interventions that rely exclusively on decision-makers'' intentions to behave equitably may be ineffective.  相似文献   

6.
The commercial cultivation of genetically modified (GM) crops in the European Union (EU) necessitates, according to EU legislation, the setting up of a General Surveillance (GS) system that should be able to detect unanticipated effects of GM crops on the environment. Although the applicant is responsible for setting up GS as well as for reporting the results, EU Member States may implement additional supporting surveillance programmes. Devising a GS system to detect unanticipated effects is not straightforward and requires clearly defined protection goals, suitable indicators that are linked to measurable parameters and an objective system for assessing the data. This paper describes a number of recommendations for the development of a General Surveillance system of the soil ecosystem specifically focussed on the situation in the Netherlands. The overarching protection goal of General Surveillance is ‘soil quality’, which is translated into more practical terms of ecosystem services that are relevant for soil quality, and that can be used to select measurable parameters and thus make a link with actual measurements.Ultimately, if and when effects on ecosystem services are detected, decision makers will have to decide whether these effects are acceptable or not. As a support for these decision-making processes, this paper discusses the modalities for the development of a stakeholder participation model. The model involves three groups of persons: the land users, the soil scientists and the decision makers.For reasons of cost effectiveness, a GS system of the soil ecosystem will have to make use of existing networks. The Dutch Soil Quality Network (DSQN) offers an existing infrastructure for soil sampling for GS. Finally, the GS system may be extended to contain data from the Dutch Ecological Monitoring Network, earth observation systems as well as other data resources such as farmers questionnaires or reports form organisations involved in nature conservation. Ideally these data are compiled by a Central Reporting Office (CRO) and maintained in a Geographic Information System (GIS) based database.  相似文献   

7.
Summary The effects of a number of organic reagents on the structure of the mitotic apparatus (MA) of several invertebrate eggs were investigated. In general, the agents induced either a large increase in the volume and retardation of the MA (hexylene glycol, dimethylsulfoxide, etc.) or caused it to partially or completely disappear (formamide, dithiodiglycol, dimethylacetamide, etc.). The immediate effects of the agents on the MA were reversible, but reversibility of embryonic development was only obtained if the eggs did not remain in the reagent for too long a time. The analysis of the specific effects of these agents suggests that the eggs utilized possess a pool of unoriented (or unpolymerized) MA material which may be reversibly affected by the agents studied. In the case of augmenting agents, the material is oriented into the MA or into aster-like bodies, in the case of dispersing agents, the material returns to the pool. Although no decision could be made as to whether the agents act directly or indirectly on the MA, the totality of the observations support the latter possibility.  相似文献   

8.

Background

The use of research evidence to underpin public health policy is strongly promoted. However, its implementation has not been straightforward. The objectives of this systematic review were to synthesise empirical evidence on the use of research evidence by public health decision makers in settings with universal health care systems.

Methods

To locate eligible studies, 13 bibliographic databases were screened, organisational websites were scanned, key informants were contacted and bibliographies of included studies were scrutinised. Two reviewers independently assessed studies for inclusion, extracted data and assessed methodological quality. Data were synthesised as a narrative review.

Findings

18 studies were included: 15 qualitative studies, and three surveys. Their methodological quality was mixed. They were set in a range of country and decision making settings. Study participants included 1063 public health decision makers, 72 researchers, and 174 with overlapping roles. Decision making processes varied widely between settings, and were viewed differently by key players. A range of research evidence was accessed. However, there was no reliable evidence on the extent of its use. Its impact was often indirect, competing with other influences. Barriers to the use of research evidence included: decision makers'' perceptions of research evidence; the gulf between researchers and decision makers; the culture of decision making; competing influences on decision making; and practical constraints. Suggested (but largely untested) ways of overcoming these barriers included: research targeted at the needs of decision makers; research clearly highlighting key messages; and capacity building. There was little evidence on the role of research evidence in decision making to reduce inequalities.

Conclusions

To more effectively implement research informed public health policy, action is required by decision makers and researchers to address the barriers identified in this systematic review. There is an urgent need for evidence to support the use of research evidence to inform public health decision making to reduce inequalities.  相似文献   

9.
UDP-glucuronosyltransferase (UGT) isozymes detoxify metabolites, drugs, toxins, and environmental chemicals via conjugation to glucuronic acid. Based on the extended UGT1 locus combined with Northern blot analysis and in situ hybridization, we determined the distribution of UGT1A1 and UGT1A7 through UGT1A10 mRNAs and found them for the first time segmentally distributed in the mucosal epithelia layer of the gastrointestinal tract. Biochemically, recombinant isozymes exhibited pH optima of 5.5, 6.4, 7.6, 8.5, and/or a broad pH range, and activities were found to be unaffected or progressively inhibited by increasing substrate concentrations after attaining Vmax for certain chemicals. Under different optimal conditions, all exhibited wide substrate selections for dietary and environmentally associated chemicals. Evidence also suggests tandem effects of isozymes in the time for completion of reactions when comparing short- and long-term incubations. Moreover, treatment of colon cells with certain diet-associated constituents, curcumin and nordihydroguaiaretic acid, reversibly targets UGTs causing inhibition without affecting protein levels; there is no direct inhibition of control UGT using curcumin as substrate in the in vitro assay. In summary, we demonstrate that UGTs are located in gastrointestinal mucosa, have vast overlapping activities under differential optimal conditions, and exhibit marked sensitivity to certain dietary substrates/constituents, representing a first comprehensive study of critical properties concerning glucuronidating isozymes in alimentary tissues. Additionally, the highly dynamic, complex, and variable properties necessarily impact absorption of ingested chemicals and therapeutic drugs.  相似文献   

10.
Human efforts to produce food and energy are changing the nitrogen (N) cycle of the Earth. Many of these changes are highly beneficial for humans, while others are detrimental to people and the environment. These changes transcend scientific disciplines, geographical boundaries, and political structures. They challenge the creative minds of natural and social scientists, economists, engineers, business leaders, and decision makers. The Second International Nitrogen Conference was designed to facilitate communications among all stakeholders in the "nitrogen community" of the world. The Conference participants" goal in the years and decades ahead is to encourage every country to make optimal choices about N management in food production and consumption, energy production and use, and environmental protection. Scientific findings and recommendations for decision makers that emerged from the Conference are presented.  相似文献   

11.
Coffea canephora plants (clone INCAPER-99) were submitted to low N (LN) or high N (HN) applications and two watering regimes (daily irrigation and irrigation every 5 days for a month). Although water potential was not altered significantly by N, HN plants showed higher relative water content than did LN plants under water deficit. Only HN plants exhibited some ability for osmotic adjustment. Plants from both N treatments increased their cell wall rigidity under drought, with a more pronounced augmentation in HN plants. In well-watered plants, carbon assimilation rate increased with increasing N while stomatal conductance did not respond to N supply. Under drought conditions, carbon assimilation decreased by 68-80% compared to well-watered plants, whereas stomatal conductance and transpiration rate declined by 35% irrespective of the N applications. Stable carbon isotope analysis, combined with leaf gas exchange measurements, indicated that regardless of the watering treatments, N increased the long-term water use efficiency through changes in carbon assimilation with little or no effect on stomatal behaviour.  相似文献   

12.
Debates over how to determine age of consent for youth to participate in research feature prominently in the practice of researchers, research ethics boards (REBs), and community decision makers working with youth. In particular, tensions can arise over how the ethical principles of beneficence, autonomy, and justice are interpreted and applied in research involving young people. We discuss our experiences obtaining ethical approval to conduct a participatory action research project involving youth and the differences of opinion we encountered regarding underage youth's capability to make informed consent. We suggest that researchers, REBs, and community decision makers all share a responsibility to conduct proactive outreach to youth participants, so that they are adequately informed of their rights related to research.  相似文献   

13.
Saccharomyces cerevisiae Y185, enriched in linoleyl residues and incubated for up to 4 h in derepression buffer, more rapidly acquired general amino-acid permease (GAP) activity, as measured by the rate of accumulation of L-alanine, compared with organisms enriched in oleyl residues. A GAP-less mutant incubated under the same conditions did not acquire further L-alanine-accumulating ability, irrespective of the nature of the fatty-acyl enrichment. During derepression, KT values for the GAP were virtually identical irrespective of the fatty-acyl enrichment, but Vmax values were greater for linoleyl residue-enriched organisms, particularly after 1 h in derepression buffer. During incubation in derepression buffer, organisms with either fatty-acyl enrichment did not differ in the size of the amino-N pool, the concentration of L-alanine in that pool, rates of protein synthesis and glucose fermentation, or rate and extent of incorporation of label from H2 32PO-4. Under conditions used to measure rates of L-alanine accumulation, organisms with either enrichment showed no evidence of metabolism of accumulated L-alanine.  相似文献   

14.
Under exchange conditions (no net increase in calcium), erythrocytes incubated in isoosmotic phosphate-buffered saline have an exchangeable calcium pool comprising about 10% of the total erythrocyte calcium. This pool reaches exchange equilibrium, for either inward-directed or outward-directed transfer of the 45Ca-exchange label, with a half-time of about 20 min. The uptake of Ca2+ requires phosphate, even under hypo-osmotic conditions, where the calcium loading expected as the cells swell is obtained only when phosphate is present. The phosphate requirement is not due to Ca2+ transport as a phosphate salt. This exchangeable-calcium pool is also present in sickle-cell-anemia erythrocytes, and comprises a similar proportion of total cellular calcium.  相似文献   

15.
Frank MJ  Woroch BS  Curran T 《Neuron》2005,47(4):495-501
The error-related negativity (ERN) is an electrophysiological marker thought to reflect changes in dopamine when participants make errors in cognitive tasks. Our computational model further predicts that larger ERNs should be associated with better learning to avoid maladaptive responses. Here we show that participants who avoided negative events had larger ERNs than those who were biased to learn more from positive outcomes. We also tested for effects of response conflict on ERN magnitude. While there was no overall effect of conflict, positive learners had larger ERNs when having to choose among two good options (win/win decisions) compared with two bad options (lose/lose decisions), whereas negative learners exhibited the opposite pattern. These results demonstrate that the ERN predicts the degree to which participants are biased to learn more from their mistakes than their correct choices and clarify the extent to which it indexes decision conflict.  相似文献   

16.
The in vivo activity of nitrogenase under aerobiosis was studied with diazotrophic chemostat cultures of Azotobacter vinelandii grown under glucose- or phosphate-limited conditions at different dilution rates (Ds, representing the growth rate mu) and different dissolved oxygen concentrations. Under steady-state conditions, the concentration as well as the cellular level of ATP increased in glucose-limited cultures when D was increased. Irrespective of the type of growth limitation or the dissolved oxygen concentration, the steady-state concentrations of ATP and of dinitrogen fixed by nitrogenase increased in direct proportion to each other. Specific rates of dinitrogen fixation as well as of the regeneration of the cellular ATP pool were compared with specific rates of cellular respiration. With glucose-limited cultures, the rate of regeneration of the ATP pool and the rate of respiration varied in direct proportion to each other. This relationship, however, was dependent on the dissolved oxygen concentration. As compared to the phosphate-sufficient control, phosphate-limited cultures exhibited the same nitrogenase activity but significantly increased respiratory activities. Rates of ATP regeneration and of cellular respiration of phosphate-limited cultures did not fit into the relationship characteristic of glucose-limited cultures. However, a linear relationship between the rates of dinitrogen fixation and ATP regeneration was identified irrespective of the type of growth limitation and the dissolved oxygen concentration. The results suggest that the ATP supply rather than cellular oxygen consumption is of primary importance in keeping nitrogenase activity in aerobic cultures of A. vinelandii.  相似文献   

17.
The need for broadening a crop’s genetic base may be determined by comparing allele frequencies within the gene pools of farmer selections in their centers of diversity with that of modern breeding populations. The genetic structure of Andean and Chilean potato farmer selections was investigated with the aid of nine isozymes, which have been studied in detail and used to characterize North American cultivars and advanced breeding lines. These isozymes are associated with the most-important agronomic or quality characters in the North American gene pool. By comparing these data with previous analyses of the North American gene pool, allozyme frequency changes for nine loci were monitored. Allozyme frequency changes were not always due to genetic drift, but resulted also from directional selection of isozyme marker linked quantitative trait loci (QTLs) affecting agronomic or quality characters. Changes in allozyme frequency can also occur as a consequence of pleiotropy, i.e. the isozyme itself may be involved in the expression of a phenotype. These allozyme frequency changes may reflect the manipulation of the potato genome by breeders. There were allozymes in some North American cultivars that were not observed in the farmer selections from the Andes and Chile. This confirms that breeders have already introgressed exotic genes from wild and other primitive cultivated tuber-bearing Solanum species. On this basis, the need for broadening the genetic base for specific chromosomes (or chromosome regions) should be based on analysis with these and other genetic markers available in potato. Received: 20 November 2000 / Accepted: 27 December 2000  相似文献   

18.
Evidence-based medicine (EBM) aims to address the persistent problem of clinical practice variation with the help of various tools, including standardized practice guidelines. Based on a systematic evaluation of the available scientific evidence, these guidelines offer recommendations for clinicians about details of patient care and clinical decision making. Because clinical practice guidelines specify how health care should be performed, they could be considered a threat to clinical and professional autonomy. Inspired by the theory of countervailing powers, this article explores how clinical practice guidelines have shifted the focus of professional power from autonomy to accountability. Professional organizations develop clinical practice guidelines as a service to their members but do not require strict adherence to the guidelines. Indeed, implementation studies show at best a modest change in clinical behavior. Such non-adherence might render a profession vulnerable, however, when third parties seize upon guidelines and offer financial incentives to keep clinicians accountable for delivering optimal patient care.  相似文献   

19.
J Lomas  G Veenstra  J Woods 《CMAJ》1997,156(5):669-676
OBJECTIVE: To obtain information from the members of the boards of devolved health care authorities on their motivations, attitudes and approaches, to evaluate their relative orientations to the expectations of provincial governments, local providers and community members, and to evaluate the influence of members'' being employees in health care or social services and being willing to stand for election. DESIGN: Mail survey conducted in cooperation with the devolved authorities during the summer of 1995. SETTING: Three provinces (Alberta, Saskatchewan and Prince Edward Island) with established boards and 2 provinces (British Columbia and Nova Scotia) with immature boards. PARTICIPANTS: All 791 members of the boards of devolved authorities in the 5 provinces, of whom 514 (65%) responded. OUTCOME MEASURES: Respondents'' declared motivations, levels of confidence in board performance and attitudes toward accountability; differences between members who were willing to run for election to boards and others and differences between members who were employees in health care or social services and others. RESULTS: The main motivations of board members were an interest in health care and a desire to be part of decision-making and their main concern was inadequacy of data for decision-making. Almost all (93%) felt that they made good decisions, and 69% thought that they made better decisions than those previously made by the provincial government. Most (72%) felt that they were accountable to all of the local citizens, although nearly 30% stated that they represented the interests of a specific geographic area or group. Attitudes toward their provincial governments were polarized, with half agreeing and half disagreeing that provincial rules restrict the board members. The board members who were employed in health care and social services and those who were willing to stand for election did not differ substantially from their counterparts, although potential electoral candidates were less likely than others to feel accountable to provincial-level constituencies (such as taxpayers and the minister of health) and more likely to represent the interests of a specific geographic area or group. Only a modest number of differences were found among members from different provinces. CONCLUSIONS: Board members'' strong feelings of accountability to and representation of local citizens could counteract the structural influences leading board members to favour the interests of provincial governments and providers.  相似文献   

20.
Abstract. The concept of species pool is reviewed. It is suggested to maintain the terms regional pool and local pool but replace actual pool by community pool. The regional and local pool are considered as selections from the regional and local flora based on ecological similarity. It is also suggested to include in the community pool a selection of species present only as diaspores in the diaspore bank (including diaspores from the seed rain), the selection being based on the same ecological criteria. Four approaches to determine the species pool are discussed: ecological, functional and phytosociological similarity, and an experimental approach. The phytosociological approach appears to be promising. The species pool is elaborated as a fuzzy set in the sense that each species of a community or a local or regional flora is a member of any community, local or regional species pool with different degrees of membership. This membership is defined as a probability of a species to become part of the community pool of a target community which is a function of the ecological (environmen-tal/functional/phytosociological) similarity of the species with the target community; the shortness of the distance of its nearest populations, the frequency/abundance, the dispersal capacity, the actual presence of dispersal mechanisms, the germinability of newly arrived diaspores, and the longevity of seeds (viability) in the diaspore bank. The information on species pools is needed for designing experiments where the number of species in a community is to be manipulated, for instance in restoration management.  相似文献   

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