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1.
The environmental health goals of many Native American tribes are to restore natural resources and ensure that they are safe to harvest and consume in traditional subsistence quantities. Therefore, it is important to tribes to accurately estimate risks incurred through the consumption of subsistence foods. This article explores problems in conventional fish consumption survey methods used in widely cited tribal fish consumption reports. The problems arise because of the following: (1) widely cited reports do not clearly state what they intend to do with the data supporting these reports, (2) data collection methods are incongruent with community norms and protocols, (3) data analysis methods omit or obscure the highest consumer subset of the population, (4) lack of understanding or recognition of tribal health co‐risk factors, and (5) restrictive policies that do not allow inclusion of tribal values within state or federal actions. In particular, the data collection and analysis methods in current tribal fish consumption surveys result in the misunderstanding that tribal members are satisfied with eating lower contemporary amounts of fish and shellfish, rather than the subsistence amounts that their cultural heritage and aboriginal rights indicate. A community‐based interview method developed in collaboration with and used by the Swinomish Tribe is suggested as a way to gather more accurate information on contemporary consumption rates. For traditional subsistence rates, a multidisciplinary reconstruction method is recommended.  相似文献   

2.
The Great Lakes Indian Fish and Wildlife Commission (GLIFWC) has produced Ogaa (walleye— Sander vitreus ) consumption advisories since 1996 for Anishinaabe from GLIFWC member tribes in the 1837 and 1842 ceded territories of Wisconsin. GLIFWC's advisory maps were revised in 2005 to address cultural sensitivities (to protect tribal lifeways), to utilize recent mercury exposure information, and to incorporate changes in advisory levels for methyl mercury. Lake-specific, risk-based, culturally sensitive consumption advice was provided on color-coded maps for two groups: children under age 15 years and females of childbearing age, and males 15 years and older and females beyond childbearing age. The maps were distributed to, and a behavioral intervention program developed for, the six GLIFWC member tribes in Wisconsin as well as member tribes in Minnesota and the 1842 ceded territory of Michigan. Tribal fish harvesters, tribal health care providers, women of childbearing age or with young children, tribal leaders, elders, and children were targeted specifically for the behavioral intervention. The efficacy of the behavioral intervention was assessed using surveys of 275 tribal fish harvesters from Wisconsin, 139 tribal harvesters from Michigan and Minnesota, and 156 Wisconsin women of childbearing age. Significant increases in the percentage of survey participants who indicated awareness of advisory maps occurred among Wisconsin harvesters (increase from 60% to 77%), Michigan and Minnesota harvesters (29% to 51%), and women of childbearing age in Wisconsin (40% to 87%). A significant increase in preference for smaller Ogaa occurred among tribal harvesters in Wisconsin (41% to 72%) and tribal harvesters in Michigan and Minnesota (49% to 71%), although not among women of childbearing age. The GLIFWC map-based advisory program did not adversely affect tribal harvest of Ogaa, which increased from 63,000 to 88,000 fish in the three states after the intervention.  相似文献   

3.
Systematic reuse can dramatically improve software development productivity and quality even though a software reuse methodology may require substantial investments. Some projects may fail to achieve the targeted amounts of reuse within organizations that are overall successful in employing reuse. To explain such variation, this research explores the effects of project‐level factors in the success of software reuse. A model that relates project factors to project reuse success is developed using an information‐rich case study approach. The results are based on the insights obtained in a nominal group technique session, triangulated with structured interviews and comparative case studies. Success factors identified by the study relate to client influence, project culture, project attributes, and developer reuse experience. An organization that can successfully identify the factors affecting potential software reuse will be able to better target investments for the improvement of its reuse methodology and thus positively affect its software development productivity and quality.  相似文献   

4.
Sampling is fundamental to the credibility of any empirical investigation, and this is no different for populations with an invisible stigma (such as sexual orientation, illness or disability). The purpose of this paper is therefore to provide an empirical assessment of the strengths of web surveys over hard‐copy surveys in conducting research targeting groups with an invisible stigma. Using a sample of gay men, this study demonstrates that when employed with a broad‐based recruitment strategy web surveys increase rather than reduce sampling coverage for invisible stigmatized populations. Further, we provide evidence that the web survey technique can yield data of comparable quality to that obtained with a hard‐copy survey. The paper concludes with strategies researchers and organizations can adopt to overcome barriers in obtaining a diverse sample when using web surveys and can be used by organizations as a mechanism for creating an inclusive culture by ‘listening to the voices’ of individuals belonging to an invisible stigmatized group.  相似文献   

5.
The intake of methyl‐Hg and EPA + DHA through consumption of seafood in Europe as well as the associated probability of exceeding the provisional tolerable weekly intake (PTWI) and the recommended daily intake (RDI), respectively, were estimated by combining methyl‐Hg and EPA + DHA contents in the five most consumed seafood species with hypothesized consumption distributions for eight European countries, chosen on the basis of size and representative significance. Two estimators were used: plug‐in (PI) and tail estimation (TE). The latter was based on the application of the extreme value theory to the intakes distribution curves. Whereas contents data were collected from own database and published scientific papers, consumption data were obtained from statistical sources of the various countries. Seafood consumption levels varied considerably between countries, from 140 in the United Kingdom to 628.5 g/(person.week) in Iceland. The main consumed species were also different between countries. The probability of exceeding the methyl‐Hg PTWI ranged from 0.04% in the United Kingdom to 9.61% in Iceland. Concerning the probability of exceeding the RDI of EPA + DHA, Iceland was third, after Portugal (66.05%) and Spain (61.05%) and the United Kingdom was the last (0.32%). While TE was most accurate for small probabilities, PI yielded best estimates for larger probabilities.  相似文献   

6.
Inorganic arsenic (iAs), cadmium (Cd), lead (Pb), and methylmercury (MeHg) are toxic metals that cause substantial health concern and are present in various seafood items. This study linked probabilistic risk assessment to the interactive hazard index (HIINT) approach to assess the human mixture risk posed by the dietary intake of iAs, Cd, Pb, and MeHg from seafood for different age populations, and joint toxic actions and toxic interactions among metals were also considered in the assessment. We found that, in combination, an iAs–Cd–Pb–MeHg mixture synergistically causes neurological toxicity. Furthermore, an iAs–Cd–Pb mixture antagonistically causes renal and hematological effects and additively causes cardiovascular effect. Our results demonstrated that if toxic interactions are not considered, the health risk may be overestimated or underestimated. The 50th percentile HIINT estimates in all age populations for neurological, renal, cardiovascular, and hematological effects were lower than 1; however, the 97.5th percentile HIINT estimates might exceed 1. In particular, toddlers and preschoolers had the highest neurological risk, with 0.16 and 0.19 probabilities, respectively, of neurological HIINT exceeding 1. Saltwater fish consumption was the principal contributor to the health risk. We suggest that regular monitoring of metal levels in seafood, more precise dietary surveys, further toxicological data, and risk–benefit analysis of seafood consumption are warranted to improve the accuracy of human mixture risk assessment and determine optimal consumption.  相似文献   

7.
《Risk analysis》2018,38(6):1116-1127
Accurate estimates of the amount and type of fish people eat are necessary to determine the health benefits and risks of consuming fish, and to assess compliance with fish consumption guidelines issued for fish affected by chemical contaminants. We developed a web‐based and mobile‐phone‐enabled diary methodology to collect detailed fish consumption information for two 16‐week periods in the summers of 2014 and 2015. We recruited study participants from two populations living in the Great Lakes region—women of childbearing age (WCBA) and urban residents who had purchased fishing licenses. In this article, we describe the methodology in detail and provide evidence related to participation rates, the representativeness of our sample over time, and both convergent validity and reliability of the data collection methods. Overall, 56% of WCBA and 50% of urban anglers provided complete data across both data collection periods. Among those who provided information at the beginning of Year 2, 97% of both audiences provided information throughout the entire 16‐week period. Those who participated throughout the two‐year period were slightly older on average (1.9–2.5 years) than other members of our original samples. We conclude that using diaries with web and smartphone technology, combined with incentives and persistent communication, has strong potential for assessing fish consumption in other areas of the country or for situations where the potential risks associated with fish consumption are substantial and the cost can be justified.  相似文献   

8.
The aim of this study was to evaluate the effects of implemented control measures to reduce illness induced by Vibrio parahaemolyticus (V. parahaemolyticus) in horse mackerel (Trachurus japonicus), seafood that is commonly consumed raw in Japan. On the basis of currently available experimental and survey data, we constructed a quantitative risk model of V. parahaemolyticus in horse mackerel from harvest to consumption. In particular, the following factors were evaluated: bacterial growth at all stages, effects of washing the fish body and storage water, and bacterial transfer from the fish surface, gills, and intestine to fillets during preparation. New parameters of the beta‐Poisson dose‐response model were determined from all human feeding trials, some of which have been used for risk assessment by the U.S. Food and Drug Administration (USFDA). The probability of illness caused by V. parahaemolyticus was estimated using both the USFDA dose‐response parameters and our parameters for each selected pathway of scenario alternatives: washing whole fish at landing, storage in contaminated water, high temperature during transportation, and washing fish during preparation. The last scenario (washing fish during preparation) was the most effective for reducing the risk of illness by about a factor of 10 compared to no washing at this stage. Risk of illness increased by 50% by exposure to increased temperature during transportation, according to our assumptions of duration and temperature. The other two scenarios did not significantly affect risk. The choice of dose‐response parameters was not critical for evaluation of control measures.  相似文献   

9.
Outsourcing of production has escalated over the past decade due to unprecedented competition and worldwide access to low‐cost labor markets. This article examines how cost and quality priorities—two key attributes of manufacturing strategy—influence a manufacturer's propensity to outsource. By doing so, we bridge the existing gap between research on manufacturing strategy and firm boundaries. We develop a theory‐based model that links a manufacturer's cost and quality priorities to its plans to outsource production. Our empirical analyses, based on survey data obtained from 867 manufacturing business units, control for firm‐specific factors previously shown to impact outsourcing, including asset specificity, uncertainty, and current capabilities in cost and quality. We found that the competitive priority placed on cost played an integral role in sourcing decisions, while, surprisingly, conformance quality priorities did not. The cost result is consistent with our expectations and observations in practice. The significant effect of cost priority on outsourcing shows that any theory of firm boundaries that fails to consider competitive priorities is incomplete. The finding regarding quality, which was counter to our expectations, may partially explain why there is an emergence of so many nonconforming products associated with outsourcing. Taken together, our results provide theoretical insights for future research into how manufacturing managers can improve their decision making on outsourcing production.  相似文献   

10.
《Risk analysis》2018,38(9):1944-1961
Following oil spills such as the Deepwater Horizon accident (DWH), contamination of seafood resources and possible increased health risks attributable to consumption of seafood in spill areas are major concerns. In this study, locally harvested finfish and shrimp were collected from research participants in southeast Louisiana and analyzed for polycyclic aromatic hydrocarbons (PAHs). PAHs are some of the most important chemicals of concern regarding oil‐spill‐contaminated seafood resources during and following oil spills. Some PAHs are considered carcinogens for risk assessment purposes, and currently, seven of these can be combined in lifetime cancer risk assessments using EPA approaches. Most PAHs were not detected in these samples (minimum detection limits ranged from 1.2 to 2.1 PPB) and of those that were detected, they were generally below 10 PPB. The pattern of detected PAHs suggested that the source of these chemicals in these seafood samples was not a result of direct contact with crude oil. Lifetime cancer risks were assessed using conservative assumptions and models in a probabilistic framework for the seven carcinogenic PAHs. Lifetime health risks modeled using this framework did not exceed a 1/10,000 cancer risk threshold. Conservative, health‐protective deterministic estimates of the levels of concern for PAH chemical concentration and seafood intake rates were above the concentrations and intake rates modeled under this probabilistic framework. Taken together, consumption of finfish and shrimp harvested from southeast Louisiana following the DWH does not pose unacceptable lifetime cancer risks from these seven carcinogenic PAHs even for the heaviest possible consumers.  相似文献   

11.
This paper describes the theoretical background, methodology, and results of a small water-pollution study conducted in a suburban Canadian community. In the study, preferences of heads of households were determined for different levels of environmental water quality and cost to the household of achieving this quality. Inferences are drawn from the preference data about the underlying individual utility functions. Implications of the study methodology and results for social decision making are discussed.  相似文献   

12.
An exposure model was developed to relate seafood consumption to levels of methylmercury (reported as mercury) in blood and hair in the U.S. population, and two subpopulations defined as children aged 2-5 and women aged 18-45. Seafood consumption was initially modeled using short-term (three-day) U.S.-consumption surveys that recorded the amount of fish eaten per meal. Since longer exposure periods include more eaters with a lower daily mean intake, the consumption distribution was adjusted by broadening the distribution to include more eaters and reducing the distribution mean to keep total population intake constant. The estimate for the total number of eaters was based on long-term purchase diaries. Levels of mercury in canned tuna, swordfish, and shark were based on FDA survey data. The distribution of mercury levels in other species was based on reported mean levels, with the frequency of consumption of each species based on market share. The shape distribution for the given mean was based on the range of variation encountered among shark, tuna, and swordfish. These distributions were integrated with a simulation that estimated average daily intake over a 360-day period, with 10,000 simulated individuals and 1,000 uncertainty iterations. The results of this simulation were then used as an input to a second simulation that modeled levels of mercury in blood and hair. The relationship between dietary intake and blood mercury in a population was modeled from data obtained from a 90-day study with controlled seafood intake. The relationship between blood and hair mercury in a population was modeled from data obtained from several sources. The biomarker simulation employed 2,000 simulated individuals and 1,000 uncertainty iterations. These results were then compared to the recent National Health and Nutrition Examination Survey (NHANES) that tabulated blood and hair mercury levels in a cross-section of the U.S. population. The output of the model and NHANES results were similar for both children and adult women, with predicted mercury biomarker concentrations within a factor of two or less of NHANES biomarker results. However, the model tended to underpredict blood levels for women and overpredict blood and hair levels for children.  相似文献   

13.
Marc Kennedy  Andy Hart 《Risk analysis》2009,29(10):1427-1442
We propose new models for dealing with various sources of variability and uncertainty that influence risk assessments for dietary exposure. The uncertain or random variables involved can interact in complex ways, and the focus is on methodology for integrating their effects and on assessing the relative importance of including different uncertainty model components in the calculation of dietary exposures to contaminants, such as pesticide residues. The combined effect is reflected in the final inferences about the population of residues and subsequent exposure assessments. In particular, we show how measurement uncertainty can have a significant impact on results and discuss novel statistical options for modeling this uncertainty. The effect of measurement error is often ignored, perhaps due to the laboratory process conforming to the relevant international standards, for example, or is treated in an  ad hoc  way. These issues are common to many dietary risk analysis problems, and the methods could be applied to any food and chemical of interest. An example is presented using data on carbendazim in apples and consumption surveys of toddlers.  相似文献   

14.
Communicating about the health effects of fish and seafood may potentially result in a conflict situation: increasing intake is desirable because of health and nutritional benefits, but higher consumption may also lead to an increased intake of potentially harmful environmental contaminants. In order to anticipate the communication challenge this conflict may pose, the research presented here aimed to assess the impact of risk/benefit communication on Belgian consumers' fish consumption behavior and fish attribute perception. Data were collected in June 2005 from a sample of 381 women, aged between 20 and 50 years. An experimental design consisting of four message conditions (benefit‐only; risk‐only; benefit‐risk; and risk‐benefit) combined with three information sources (fish and food industry; consumer organization; government) was used. Exposure to the benefit‐only message resulted in an increase from a self‐reported fish consumption frequency of 4.2 times per month to an intended fish consumption frequency of 5.1 times per month (+21%), while fish attribute perceptions only marginally improved. The risk‐only message resulted in a strong negative perceptual change in the range of two points on a seven‐point scale. This translated into an 8% decrease of behavioral intention (from eating fish 4.5 times per month to an intention of eating fish 4.1 times per month). Balanced messages referring to both risks and benefits yielded no significant change in behavioral intention, despite a significant worsening of fish attribute perception. The presentation order of benefits and risks in the balanced message showed a tendency to affect both behavioral intention and attribute perception, with the first message component being most influential. Information source did not yield any significant impact either on behavioral intention or on attribute perceptions, independent of the message content. The results from this study provide valuable insights for future risk/benefit and balanced communication about seafood.  相似文献   

15.
To inform source attribution efforts, a comparative exposure assessment was developed to estimate the relative exposure to Campylobacter, the leading bacterial gastrointestinal disease in Canada, for 13 different transmission routes within Ontario, Canada, during the summer. Exposure was quantified with stochastic models at the population level, which incorporated measures of frequency, quantity ingested, prevalence, and concentration, using data from FoodNet Canada surveillance, the peer‐reviewed and gray literature, other Ontario data, and data that were specifically collected for this study. Models were run with @Risk software using Monte Carlo simulations. The mean number of cells of Campylobacter ingested per Ontarian per day during the summer, ranked from highest to lowest is as follows: household pets, chicken, living on a farm, raw milk, visiting a farm, recreational water, beef, drinking water, pork, vegetables, seafood, petting zoos, and fruits. The study results identify knowledge gaps for some transmission routes, and indicate that some transmission routes for Campylobacter are underestimated in the current literature, such as household pets and raw milk. Many data gaps were identified for future data collection consideration, especially for the concentration of Campylobacter in all transmission routes.  相似文献   

16.
A number of market changes are impacting the way financial institutions are managing their automated teller machines (ATMs). We propose a new class of adaptive data‐driven policies for a stochastic inventory control problem faced by a large financial institution that manages cash at several ATMs. Senior management were concerned that their current cash supply system to manage ATMs was inefficient and outdated, and suspected that using improved cash management could reduce overall system cost. Our task was to provide a robust procedure to tackle the ATM's cash deployment strategies. Current industry practice uses a periodic review system with infrequent parameter updates for cash management based on the assumption that demand is normally distributed during the review period. This assumption did not hold during our investigation, warranting a new and robust analysis. Moreover, we discovered that forecast errors are often not normally distributed and that these error distributions change dramatically over time. Our approach finds the optimal time series forecaster and the best‐fitting weekly forecast error distribution. The guaranteed optimal target cash inventory level and time between orders could only be obtained through an optimization module that was embedded in a simulation routine that we built for the institution. We employed an exploratory case study methodology to collect cash withdrawal data at 21 ATMs owned and operated by the financial institution. Our new approach shows a 4.6% overall cost reduction. This reflects an annual cost savings of over $250,000 for the 2,500 ATM units that are operated by the bank.  相似文献   

17.
The impact of forecast error magnification on supply chain cost has been well documented. Unlike past studies that measure forecast error in terms of forecast standard deviation, our study extends research to consider the impact of forecast bias, and the complex interaction between these variables. Simulating a two‐stage supply chain using realistic cost data we test the impact of bias magnification comparing two scenarios: one with forecast sharing between retailer and supplier, and one without. We then corroborate findings via survey data. Results show magnification of forecast bias to have a considerably greater impact on supply chain cost than magnification of forecast standard deviation. Particularly damaging is high bias in the presence of high forecast standard deviation. Forecast sharing is found to mitigate the impact of forecast error, however, primarily at higher levels of forecast standard deviation. At low levels of forecast standard deviation the benefits are not significant suggesting that engaging in such mitigation strategies may be less effective when there is little opportunity for improvement in accuracy. Furthermore, forecast sharing is found to be much less effective against high levels of bias. This is an important finding as managers often deliberately bias their forecasts and underscores the importance of exercising caution even with forecast sharing, particularly for forecasts that have inherently large errors. The findings provide a deeper understanding of the impact of forecast errors, suggest limitations of forecast sharing, and offer implications for research and practice alike.  相似文献   

18.
针对消费者对国内生鲜农产品质量安全的"信任危机",本文构建了植入消费体验的生鲜电商C2B2B2C模型,让碎片化的消费者通过互联网就近聚合为社群化的食物社区,生产者通过合作社聚合为规模化生产基地,食物社区与生产基地借助电商平台进行产销对接、以销定产和消费体验。研究表明,在传统B2C模式下消费者只能依据供应商提供的信息进行Stackelberg博弈和有限消费体验,购买需求较少。当植入充分的消费体验后,生产者与消费者融合为prosumer,购买需求随消费者对生产者的信任度增加而增加。实证揭示,农耕生产、质量追溯、物流配送、网购操作、产品呈现和售后服务都会显著影响消费体验,电商平台要实现商业可持续性发展必须为消费者设置这些全面而丰富的体验场景。  相似文献   

19.
目前,加权平均法是一种比较常见的满意度调查结果的汇总方法,但是这种方法的前提条件是决策者的偏好结构满足加性独立条件,否则需要采用非线性综合方法。本文旨在考虑决策者偏好不满足加性独立条件下,将用户满意度抽样调查过程中产生的置信度和置信区间与调查问卷中的用户不确定的评价结果统一进行考虑,并采用mass函数值为区间数的证据推理方法分析基于抽样调查得到的以置信区间表示的用户满意度调查的结果综合问题。最后以某网络信息中心用户满意度调查为例展开实证分析。  相似文献   

20.
An abundance of flawed software has been identified as the main cause of the poor security of computer networks because major viruses and worms exploit the vulnerabilities of such software. As an incentive mechanism for software security quality improvement, software liability has been intensely discussed among both academics and practitioners for a long time. An alternative approach to managing software security is patch release, which has been widely adopted in practice. In this paper, we examine these two different ways of mitigating customer risk in the software market: liability and patch release. We study the impact of both mechanisms on a monopolistic software vendor's decision on security quality. We find the conditions under which each mechanism is effective in terms of improving security quality and increasing social surplus. The heterogeneous nature of loss is identified to be a key factor for the effectiveness of the liability mechanism. On the other hand, patch release can be effective and welfare‐enhancing regardless of the nature of loss as long as customers incur low patching cost, and/or the vendor incurs low patch development cost. We also examine the impact of customer misperception of the outcome from vulnerable software on the effectiveness of liability.  相似文献   

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