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南方丘陵区新增耕地质量空间特征研究*——以江西省宜春市为例 总被引:2,自引:0,他引:2
[目的]粮食安全的根本是在耕地,关键在于耕地质量。目前新增耕地主要源于土地开发项目、城乡建设用地增减挂钩土地复垦项目等,这些新增耕地需要对其开展耕地质量等别评定工作,了解新增耕地的质量状况,分析其空间特征,这对落实国家耕地保护制度、开展农村土地整治工作等具有重要作用。[方法]文章以南方典型丘陵区域——江西省宜春市作为研究区域,在新增耕地质量评价的基础上,运用地统计学、景观生态学、Arcgis空间分析技术和典型相关分析方法,研究宜春市新增耕地质量的空间特征,掌握耕地质量等别的分布规律,了解耕地质量的影响因素,为制定合理的耕地资源利用与保护政策提供依据。[结果](1)Moran′s I值结果表明宜春市2014年新增耕地利用质量在空间分布上的空间自相关性最强,而耕地自然质量空间自相关性最弱。(2)景观破碎度指数结果表明优、高等别的新增耕地质量破碎度大于中、低等别的; 多样性指数结果表明新增耕地质量多样性指数比较大; 优势度指数结果表明新增耕地质量等别优势度指数比较小,与多样性指数结果相呼应; 均匀度指数结果表明,新增耕地质量等别均匀度指数相差不大,新增耕地质量等别比较均匀。(3)质心结果表明2013—2014年间宜春市新增耕地质量的格局整体上是向西南方向变化。[结论]宜春市新增耕地质量不高; 新增耕地的利用水平差异性较小,自然本底状况差异较大; 新增耕地质量等别类型多,各质量等别类型耕地均有增加,耕地质量参差不齐,较高等地的新增耕地相对低等地而言更破碎化; 新增耕地的开发格局向着西南方向移动; 该研究为南方丘陵区的新增耕地保护提供了一定的参考依据。 相似文献
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Aims: Depression is the most frequent comorbidity reported among patients with rheumatoid arthritis (RA). Comorbid depression negatively impacts RA patients’ health-related quality-of-life, physical function, mental function, mortality, and experience of pain and symptom severity. The objective of this study was to assess healthcare utilization, expenditures, and work productivity among patients with RA with or without depression.Materials and methods: Data from adult patients who had at least two visits each related to RA and depression over a 1-year period were extracted from the Truven Health MarketScan research databases. Outcomes comprised healthcare resource utilization, work productivity loss, and direct healthcare costs comparing patients with RA with depression (n?=?3,478) vs patients with RA without depression (n?=?43,222).Results: Patients with RA and depression had a significantly greater relative risk of hospitalization and number of all-cause and RA-related hospitalizations, utilization of emergency services, days spent in the hospital, physician visits, and RA-related surgeries compared with RA patients without depression. Patients with RA and depression had a higher risk of and experienced more events and days of short-term disability compared with patients without depression. The incremental adjusted annual all-cause and RA-related direct costs were $8,488 (95% CI = $6,793–$10,223) and $578 (95% CI = –$98–$1,243), respectively, when comparing patients with RA and depression vs RA only.Limitations: The current analysis is subject to the known limitations of retrospective studies based on administrative claims data.Conclusions: This study suggested increased healthcare utilization, work productivity loss, and economic burden among RA patients due to comorbid depression. These findings emphasize the importance of managing depression and including depression as a factor when devising treatment algorithms for patients with RA. 相似文献
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企业创新是国家经济可持续增长的关键,受到管理层意愿的影响,因而需要对内部经营者的权力进行制衡。以2010-2018年我国A股上市公司为研究样本,实证检验管理层权力制衡强度对企业创新投资的影响,以及不同债务约束情境下高商业信用配置、高负债水平的调节效应,此外,还考察了产权性质的差异化影响。研究表明,管理层权力制衡强度越大,企业创新投资水平越高;高商业信用强化了该促进作用,而高负债水平弱化了该促进作用。进一步研究发现,管理层权力制衡强度与企业创新投资的关系在民企中更显著;国企能够更好地获得和运用商业信用,使其高商业信用对该关系的强化效应更显著;民企具有更强的债务约束,其高负债水平对该关系的弱化效应更明显。 相似文献
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Motivated by the European sovereign debt crisis, we propose a hybrid sovereign default model that combines an accessible part taking into account the evolution of the sovereign solvency and the impact of critical political events, and a totally inaccessible part for the idiosyncratic credit risk. We obtain closed‐form formulas for the probability that the default occurs at critical political dates in a Markovian setting. Moreover, we introduce a generalized density framework for the hybrid default time and deduce the compensator process of default. Finally, we apply the hybrid model and the generalized density to the valuation of sovereign bonds and explain the significant jumps in long‐term government bond yields during the sovereign crisis. 相似文献
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ABSTRACTThis research introduces online travel photos published on social media platforms as a complementary data resource to examine the behavior and experience of museum visitors. The practical value of online travel photos is demonstrated through a case study of popular Hong Kong museums, particularly by using the photo content and metadata available from the Flickr platform. The proposed approach is a generic method for understanding museum visitor behavior and preferences, and supports museum practitioners in developing improved products for visitors. The case study findings are particularly beneficial for tourism managers, especially those in Hong Kong, in promoting and attracting tourists to visit local museums. 相似文献
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Zhiming Cheng Wei Guo Mathew Hayward Russell Smyth Haining Wang 《Journal of Business Venturing》2021,36(1):106063
Studies on the determinants of entrepreneurship emphasize that challenged adults tend to become entrepreneurs. However, research has not addressed the childhood origins surrounding the propensity for entrepreneurship. This article links childhood adversity to the propensity of individuals to become migrant entrepreneurs later in life. We test hypotheses derived from this theory in the context of whether, and when, children who survived the Great Chinese Famine of 1959–1961 became migrant entrepreneurs. Results strongly indicate that those who survived greater hardship during the Famine are more likely to become entrepreneurs, especially when they were younger during the famine years. We also find that being younger at the time of migration increased the likelihood of becoming entrepreneurs in their new locale. Overall, this study casts light on why, how and when childhood adversity shapes the propensity for entrepreneurship. 相似文献
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Weipeng Lin Jingjing Ma Qi Zhang Jenny Chen Li Feng Jiang 《Journal of Business Ethics》2018,152(4):1099-1115
Previous research has shown that virtuous leader behavior in the form of benevolent leadership has considerable impact on employee creativity. However, little is known as to how and under what conditions these constructs are linked. In the current research, we proposed and tested a moderated mediation model positing leader–member exchange (LMX) as a mediator, and employee power-distance orientation as a moderator of this relationship. Two studies were conducted to test our hypothesized model. In Study 1, repeated measured data collected from 284 Chinese employees in an information technology company demonstrated that benevolent leadership had a lagged effect on LMX. In Study 2, analyses of multisource and lagged data from 391 Chinese employees in 42 research and development teams, and their direct supervisors indicated that benevolent leadership was positively related to supervisor-rated employee creativity via LMX. In addition, the relationship between benevolent leadership and LMX was stronger for employees high in power-distance orientation. Theoretical implications of benevolent leadership’s research and practical contributions concerning promoting creativity in organizations where benevolent leaders prevail are also discussed. 相似文献
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基于嵌入性视角,分别引入知识转移、合作模式作为中介变量和调节变量,深入探究关系质量影响企业知识创造绩效的内在机理。利用277份来自全国多地的制造业及高新技术企业调查问卷,采用多元回归方法进行实证研究。结果表明:经济型和社会型关系质量均正向影响企业知识创造绩效;社会型关系质量通过元素知识和架构知识转移正向影响企业知识创造绩效。在契约治理模式下,经济型关系质量更倾向于通过元素知识转移正向影响企业知识创造绩效;在股权治理模式下,社会型关系质量更倾向于通过架构知识转移正向影响企业知识创造绩效。 相似文献