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1.
Canadian fruit and vegetable markets were significantly impacted by the spread of the novel coronavirus SARS-CoV-2 (and COVID-19 disease), beginning in March 2020. Due to the closure of restaurants, bars, and schools, produce growers and distributors were forced to shift supplies almost entirely from the foodservice to the retail channel. Shippers reported labor and logistical constraints in making the change, but the fresh produce supply chain remained robust. In the long term, we expect lasting changes in consumers’ online food-purchasing habits, heightened constraints on immigrant labor markets, and tighter concentration in fresh produce distribution and perhaps retailing.  相似文献   
2.
[目的]探索叶尔羌河平原绿洲土地生态安全预警问题及其时空格局变化,旨在为叶尔羌河平原绿洲土地生态安全及可持续利用提供科学的参考依据。[方法]文章运用PSR模型构建预警指标体系,采用熵值法测算各指标权重,对2000—2016年叶尔羌河平原绿洲土地生态安全警情格局进行综合分析,并利用GIS技术分析其2000年、2005年、2010年和2016年土地生态安全空间格局变化,最后运用障碍度模型探索其障碍因子。[结果](1)2000—2016年叶尔羌河平原绿洲土地生态安全综合预警指数总体呈上升态势,生态预警状态由"较不安全"转为"临界安全",警度亦由"重警"变为"中警"。(2)从空间格局来看,空间上各县域土地生态安全水平差异明显,研究初期西部地区土地生态安全状态优于东部地区, 2016年呈现出中部高、东北—西南部低的态势。(3)近17年叶尔羌河平原绿洲各县域土地生态环境状况有所改善,安全状态经历了"极不安全—临界安全—较安全"的发展历程。(4)影响土地生态安全的主要障碍因子包括单位面积耕地农药负荷、人口密度、单位面积耕地化肥负荷、土地垦殖率、人口自然增长率和单位面积耕地地膜负荷等。[结论]研究期间叶尔羌河平原绿洲土地生态安全得到明显的提升与改善,并在良好的方向发展。  相似文献   
3.
[目的]为了解叶尔羌河平原绿洲耕地利用变化与粮食产量的耦合关系,以此优化粮食生产系统的指导方式,提高叶尔羌河平原绿洲粮食产量,协调叶尔羌河平原绿洲耕地利用转型与粮食产量的耦合关系,并为叶尔羌河平原绿洲的粮食安全保护提供一定的政策启示。[方法]文章运用熵值法,以粮食生产相关的“投入”指标为评价依据,耕地利用强度由地均化肥使用强度、有效灌溉比例、复种指数及地均农业机械化水平等4个指标构成,以及利用1990—2016年叶尔羌河平原绿洲粮食产量,分析其耕地利用转型和粮食产量耦合关系时空变化。[结果](1)1990—2016年叶尔羌河平原绿洲各县耕地利用强度不断增大,并且区域时空格局差异明显,研究初期东北部地区的耕地利用程度强于西部地区,而2016年呈现出西南—中东部强,东北部弱的态势; 从粮食产量方面来看,叶尔羌河平原绿洲粮食产量整体有所增长,空间分异特征较不明显;(2)耕地利用强度—粮食产量耦合类型时空演化特征明显,高耦合值区增加,低耦合区值逐年减少; 从空间上看,叶尔羌河平原绿洲西部地区耕地利用转型与粮食产量耦合度越来越高。(3)耕地利用转型推动粮食生产格局不断演化,叶尔羌河平原绿洲耕地利用转型与粮食产量耦合度在1990—2016年呈现耦合度逐渐增加的趋势,耕地利用转型对保障区域粮食安全具有重要作用。[结论]叶尔羌河平原绿洲粮食产量随着耕地利用转型的不断深入而不断提高,耕地利用转型对粮食安全具有有利影响。  相似文献   
4.
This paper analyzes hospital characteristics that are associated with higher average costs and charges for venipuncture, computed tomography procedures (computerized axial tomography [CAT] scans), and electrocardiograms (EKG). Using data from a Medicare database, our results indicate that higher wages, larger hospital sizes, and greater service quality are associated with higher procedure costs, whereas system membership is generally associated with lower procedure costs. Blinder‐type decompositions, which are the main focus of this study, suggest (a) that venipuncture costs are about 17% to 19% lower at proprietary hospitals than at nonprofit or government hospitals, (b) CAT scan costs are about 6% to 12% lower at nonprofit hospitals than at proprietary and government hospitals, and (c) that EKG costs are about 3% lower at proprietary hospitals than at nonprofit or government hospitals. Lastly, large portions of each of these differences are found to be due to both differences in mean values of the hospitals' characteristics by ownership type and differences in the mechanism by which the hospitals' characteristics are transmitted to procedure costs.  相似文献   
5.
The long‐term fracturing of the labour movement has led to increased attention to employee coping practices under new management practices and labour processes. However, the literature caters little for the recent rise of employees taking to social networking sites (SNSs), such as Facebook, to find ways to cope with the pressures of contemporary employment. To explore the self‐organised coping qualities of SNSs, interviews were conducted with front line workers, employed by a large anti‐trade union US retailer, who contribute to a self‐organised Facebook group set up as a place for fellow employees to deal with collective employment‐related problems. The main findings suggest employee self‐organised Facebook groups represent an important development and extension to the coping practices available to individual and groups of employees. The main implication of the findings is that Facebook groups appear to strengthen and widen the options for employee resilience in an age of continuing trade union retreat.  相似文献   
6.
This article explores the market response of deep discount corporate bonds to the reduction in the capital gains tax rate incorporated into the Revenue Act of 1978. Such tax change should have increased the desirability of assets acquired for capital gains potential, such as deep discount bonds. Examining a time series of prices and returns for a sample of deep discount corporate bonds and a control group of comparable duration and credit risk corporate bonds selling at or near par did indeed provide evidence of a market price reaction. Moreover, the price changes for the deep discount bonds occurred well in advance of the implementation of the tax change.  相似文献   
7.
8.
The normative presuppositions motivating rational choice decision-making based on optimizing objectives amount to a thin account of ethical economic behavior. Ancient thought offers insights that can provide a firmer basis both for personal, individual choice as well as for public policy. After a brief review of Epicurean and Stoic ethical principles, a comparison is made of modern economic and Hellenistic conceptions of rationality and rational behavior. These competing conceptions are then applied to an examination of a contemporary public policy problem, namely health care, particularly as this applies to “end-of-life” issues. The argument concludes that decision-making based on a eudaimonic conception of the good has the potential to provide us with a more efficient health care system as well as one that more satisfactorily addresses the needs of the chronically ill and dying patients who account for a highly disproportionate share of health care expenditures.  相似文献   
9.
Recent years have seen an emergence of a varied academic literature focused on the football fan, with a wealth of studies exploring issues such as hooliganism, fan behaviour and fan identification. No research, however, has documented the experiences and perspectives of the international sojourner, who follows the televised tournament far away from the home country. This paper offers a contribution to the literature on fandom by focusing on the experiences of becoming a temporary fan among a sample of nine international students in England during the period of the 2010 FIFA World Cup. It shows the importance of the tournament for students away from their home nation, acting as a point of celebration and as a means of bringing sojourners of the same nationality together to support their team. It reveals how the tournament offered escape from stress, became a focal point for social interaction, provided the opportunity for recreation of home, and for the reinforcement of feelings of national identity.  相似文献   
10.
This article describes the history of the Aotearoa Traditional Maori Performing Arts Festival between the years of 1972–2000. It reveals a series of tensions between a need to express a cultural identity and financial constraint, between a wish for expressing independence, and a subsequent dependency upon state grants, between the traditional and the contemporary in performance. The history also shows the significance of key personalities. Yet through these discourses has emerged a successful and important Festival that attracts increasing numbers of participants and which is a dynamic component of Maori culture in contemporary New Zealand. A significant tourism event, by reason of primarily appealing to Maori it still, to a large extent, lies outside of the conventional tourism structures of New Zealand, dominated as these are by overseas visitors and non-Maori New Zealand domestic demand. Yet its very success is bringing it to the attention of a wider market, with all that implies for possible future development. The article also proposes dimensions of festival evolution and maturation.  相似文献   
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