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The COVID-19 pandemic has had a great impact on food shopping behavior. However, changes in food shopping behavior and related decision-making mechanisms remain unexplored. This study conducted a face-to-face questionnaire survey with 900 residents in three communities in Haidian, Beijing, China, to analyze food shopping behavior during the periods of pre-lockdown, lockdown (January–March 2020), and post-lockdown. Our results indicated that the preference for fresh food e-commerce shopping was accelerated by the lockdown with the usage rate increasing by 48%; the wet markets were seriously hit by the lockdown policy and had not fully recovered by the post-lockdown period (with a 75% reduction in the usage rate during lockdown). The psychological mechanisms of changes in food shopping behavior revealed that the context (e.g., community facilities) and the perceived risk of COVID-19 were two significant factors impacting the four shopping choices investigated. Specifically, the context factors affected behavior directly for supermarkets and convenience stores and indirectly for e-commerce and wet markets. The findings are expected to help in guiding emergency responses during a future pandemic as well as the long-term construction of food supply facilities.  相似文献   
3.
城市自生群落具有重要的生态服务功能与潜力,但因其外貌不被公众所接受而难以在城市公共空间中应用。将群落生态学和设计学相结合,探索一种介入栽培植物对城市自生群落进行改良,最终形成具有一定美学价值的植物群落的途径。实验以植物群落设计美学原理和种间竞争原理为依据,向已经演替1年的城市自生群落中引入63种栽培植物,按照分层的方式对群落进行改良。3年的观测结果表明,有61.9%的栽培植物可以在城市自生群落中定居并建立优势,能对76.7%的自生植物起到抑制作用,使55.8%的自生植物消失。相比城市自生群落,改良后的群落美观度提高29.4%,公众接受度提高24%,群落的物种丰富度提高至2.29倍。相比一般的人工植物群落,改良后的群落可以节约58.2%的建植成本,降低83.9%的浇水成本和67.8%的除草成本。实验证明改良设计是一种可行的群落设计途径,能有效提高群落的物种丰富度和美学价值,同时让自然参与群落设计过程,实现人与自然的合作。  相似文献   
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This study draws on customer-dominant logic and self-expansion theory to examine the drivers of customer engagement behaviors in the context of emerging online interest communities. The engagement behaviors seen in online communities are operationalized into four types: augmenting, co-developing, influencing, and mobilizing. Goal pursuit (gratifying-the-self, enabling-the-self, and enriching-the-self) and emotional attachment to the community are found to be the key antecedent factors of these behaviors. The attainment of gratifying-the-self has a direct influence on these behaviors, whereas the attainment of enabling-the-self and enriching-the-self influences them via emotional attachment to the community.  相似文献   
5.
采用响应面法优化毛竹水溶性多糖的提取工艺,分析其成分,并进行结构表征。研究结果表明,优化的毛竹多糖(BSP)提取条件为:料液比1∶27(g/mL)、提取温度78 ℃、提取时间4 h,该条件下BSP提取率为(5.18±0.07)%,提取物中多糖含量为(72.14±0.02)%,糖醛酸含量为(9.76±0.03)%;BSP具有酸性多糖典型的官能团特征吸收峰,其单糖组成及摩尔比为n甘露糖∶n葡萄糖∶n阿拉伯糖∶n木糖∶n鼠李糖∶n半乳糖=62.52∶23.05∶10.35∶2.78∶0.79∶0.51;BSP由两个主峰组成,相对分子质量分别为91.11、4.55 kDa。BSP是一种混合酸性多糖。  相似文献   
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新冠疫情的出现冲击了世界经济,从经济全球化和全球经济治理体系两个维度分析疫情对世界经济的影响以及世界经济未来走向,研究发现:(1)新冠疫情通过影响全球价值链、贸易投资和就业环境阻碍经济全球化进程,中美矛盾升级、原有治理体系规则未与时俱进和激进政策的不确定性对全球经济治理体系提出新的挑战;(2)新冠疫情强化了世界各国对人类命运共同体的认识,将人类命运共同体融入全球治理体系将是未来治理的重要趋势;(3)新冠疫情可能会使世界经济格局出现新的变化,而中国在此次疫情中高效率的抗疫举措将进一步提升自身在世界经济格局中的地位和参与度。  相似文献   
7.
Absentee landowners, or those who do not live on their forestland, own approximately 117 million acres of private forestland in the U.S. Thus, their land management decisions and activities influence the flow of forest-based goods and services. We explore the question of whether absentee family forest owners are less active land managers than resident landowners and whether membership in conservation organizations is associated with higher levels of land management activity by absentee owners. To examine these questions, we administered a mail survey to randomly-selected family forest landowners in Indiana. While we found some support for the contention that absentee owners are less active forestland managers than resident owners, we also found they are not necessarily inactive landowners. We found absentee owners were less likely to have: inspected their forestland for invasive plants, pulled or cut invasive plants, used herbicides to kill invasive plants, reduced fire hazard, or grazed livestock than resident owners. Absentee owners were more likely to be enrolled in the Indiana Classified Forest and Wildlands Program, a preferential forest property tax program. Absentee owners who are members of a conservation organization were more likely than absentee non-member owners to have undertaken a variety of land management activities, including: undertaking wildlife habitat improvement projects, inspecting their forestland for invasive plants, pulling or cutting invasive plants, enrolling in the Indiana Classified Forest and Wildlands program, and obtaining a management plan.  相似文献   
8.
Anxieties over the potential impacts of climate change, often framed in apocalyptic language, are having a profound, but little studied effect on the contemporary Western urbanscape. This article examines the ways in which current theorizations of ‘ecological gentrification’ express only half the process, describing how green space is used for social control, but not how ecology is used as a justification regime for such projects. As urbanites seek out housing and living practices that have a lower environmental impact, urban planners have responded by providing large-scale regeneration of the urbanscape. With the demand for this housing increasing, questions of inequality, displacement and dispossession arise. I ask whether apocalyptic anxiety is being enrolled in the justification regimes of these projects to make them hard to resist at the planning and implementation stages. The article shows that, in capitalizing on collective anxiety surrounding an apocalyptic future, these projects depoliticize subjects by using the empty signifier, ‘Sustainability’, leading them into an immuno-political relationship to the urbanscape. This leaves subjects feeling protected from both responsibility for, and the impacts of, climate change. Ultimately, this has the consequence of gentrification coupled with potentially worsening consumptive practices, rebound effects and the depoliticization of the environmentally conscious urbanite.  相似文献   
9.
社区商业以社区内居民为主要服务对象,以满足居民基本生活及多样化消费需求为主要目的。论文以三线城市浙江省湖州市为例,通过现场访谈与问卷调研,明确湖州市中心城区社区商业业态现状与主要存在的问题。借鉴长三角地区典型成功社区商业运营模式和操作流程,从核心理念、业态配比、品牌构建与商圈融合四个方面提出构建科学合理的湖州市社区商业业态的相关建议。  相似文献   
10.
曾向红  陈亚州 《世界经济与政治》2020,(1):102-127,158,159
构建上海合作组织命运共同体是中国政府提出的关于促进上海合作组织长远发展的重大倡议。由于上海合作组织命运共同体理念的提出时日尚短,学术界关于该理念的研究尚未全面启动。要使上海合作组织命运共同体理念成为一个有效的研究议题,不仅需要明晰上海合作组织命运共同体的具体内涵,而且需要将其纳入国际共同体、国际组织和大国外交等议题的研究,提炼出一些具有普遍性的理论命题。就攸关上海合作组织命运共同体构建的重大问题而言,至少需要回答上海合作组织命运共同体提出的理论与实践意义、上海合作组织命运共同体构建应遵循的基本路径、上海合作组织命运共同体构建的基础和条件、上海合作组织命运共同体构建面临的挑战与障碍、学术界能为上海合作组织命运共同体构建提供的对策建议等重大问题。在此过程中,学术界还需将其与周边命运共同体、人类命运共同体等家族相似性的概念纳入同一研究视域,以澄清上海合作组织命运共同体的内涵与外延,辨识上海合作组织命运共同体演变的动力与机制,并从理论层面提炼上海合作组织发展经验的特殊性与普遍性。  相似文献   
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