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991.
城市绿地是重要的绿色基础设施。城市绿地要实现设计目标,保持长久的景观效果离不开持续不断地养护管理,同时管养工作又会带来物资消耗和废弃物排放,对环境造成负面影响。基于生命周期评价方法(LCA),以资源能源消耗和气候变暖潜值作为对环境影响的主要因子,将城市绿地划分为乔木、灌木、地被和草坪层,建立了管养对环境影响的量化模型。以郑州市郑东新区绿地为研究对象,选取34个植物群落(20m×20m)为样本进行了验证,计算得到各植物层管养资源能源消耗和气候变暖潜值特征量以及管养工作标准化加权环境影响指数。结果表明,乔木的管养环境影响指数最低,比群落均值低32%;施肥和垃圾清运是环境影响的主要因素,占群落管养环境影响指数均值的75%以上;与农林业相比,城市绿地管养环境影响指数处中低水平,但资源能源消耗因子的影响指数偏高。基于LCA方法的研究结果可以为城市绿地设计和精细化管理提供量化参考。 相似文献
992.
993.
金融作为经济增长核心助推器,对其空间集聚与扩散的经济效应准确识别,是沿海地区发展蓝色经济的关键所在。本文以山东省为例,通过建立金融发展空间关联网络识别区域的金融空间关联关系,基于此设计金融关联空间权重矩阵,对金融空间关联的经济效应进行检验。结果表明:山东省城市间金融发展具有稳健的空间关联性;区域金融发展水平同区域经济发展之间存在显著正向促进效应,金融发展能有效拉动本区域经济状况,对周边区域经济正向拉动效应相对微弱。建议从加快推进区域一体化进程,加强城际间金融交流合作,鼓励金融创新发展等方面充分发挥金融发展正向溢出效应,拉动沿海地区蓝色经济向好发展。 相似文献
994.
We examine the effect of corporate social responsibility (CSR) quality ratings on the financial distress levels of Chinese enterprises by using the previously unexplored new China-specific Altman ‘ZChina Score’ in the context of CSR and data from 749 firms over the 2009–2014 period. First, we find that CSR quality ratings significantly reduce Chinese firms’ distress levels. Second, we find that the ability of CSR to reduce distress levels in non-state-owned Chinese firms is higher than state-owned ones. Finally, we find similar results when we divide the data into high-low CSR ratings and levels of distress. Our results are robust to potential endogeneities. 相似文献
995.
This article tests the Expectations Hypothesis (EH) using Brazilian monthly data for bond yields spanning the 2000–2017 sample period and ranging in maturity from 3 months to 5 years. Three tests are examined: the first is based on interest rates spread and the other two are based on the forward rates. On balance our results suggest rejection of the EH throughout the maturity spectrum examined, and are broadly consistent with previous findings that a linear combination of forward rates provides a statistically significant prediction of bond excess returns. 相似文献
996.
Abdalla Aly Courtney Johnson Shuo Yang Sumati Rao Arif Hussain 《Journal of medical economics》2019,22(7):662-670
Aims: Medicare patients with metastatic or surgically unresectable urothelial carcinoma (mUC) often receive platinum-based chemotherapy as first line of therapy (LOT), but invariably progress, requiring additional LOTs and healthcare resource use (HCRU). To better understand the evolving mUC treatment landscape, the economic burden of chemotherapy-based mUC treatments among US Medicare patients was estimated.Methods: Newly diagnosed Medicare patients with mUC were identified from the Surveillance, Epidemiology, and End Results (SEER)-Medicare database. Patients were followed from diagnosis to death, disenrollment, or end of study to characterize LOTs (first [LOT1], second [LOT2], and third or greater [LOT3+]). Kaplan-Meier methods were used to estimate overall survival (OS) by LOT. HCRU and mean costs were reported over the follow-up period, LOT duration, and maximum LOT received.Results: Among 1,873 eligible patients with mUC (median age?=?77?years; median follow-up?=?7.5?months), 1,035 (55%) received no chemotherapy. Among chemotherapy-treated patients, 61% had LOT1 only, 25% had LOT1 and LOT2 only, and 14% had LOT3+. Median OS was 8.1?months, range was 4.3 (untreated) to 29.8 (LOT3+) months. HCRU frequency increased with additional LOTs. Mean cumulative per-patient cost was $82,912 for all patients, increasing with additional LOTs (untreated?=?$57,207; LOT1?=?$99,213; LOT2?=?$125,190; LOT3+?=?$163,884). Mean per patient per month cost was $18,827 for all patients, decreasing with increasing number of LOTs received (untreated?=?$27,211; LOT1?=?$9,601; LOT2?=?$7,325; LOT3+?=?$6,017).Limitations: Potential for treatment misclassification when using the algorithm defining LOTs and non-generalizability of results to younger patients.Conclusions: Over 50% of Medicare patients with mUC received no chemotherapy. Among chemotherapy-treated patients, most received only one LOT. Additional LOTs led to higher mean costs and HCRU, but as patients were followed longer, monthly costs decreased. As treatments evolve to include immuno-oncology agents, these findings provide a clinically relevant economic benchmark for mUC treatment across different traditional LOTs. 相似文献
997.
Chung-Ping A. Loh Kristopher P. Croome C. Burcin Taner Andrew P. Keaveny 《Journal of medical economics》2019,22(7):684-690
Background: Fast-tracking is an approach adopted by Mayo Clinic in Florida’s (MCF) liver transplant (LT) program, which consists of early tracheal extubation and transfer of patients to surgical ward, eliminating a stay in the intensive care unit in select patients. Since adopting this approach in 2002, MCF has successfully fast-tracked 54.3% of patients undergoing LT.Objectives: This study evaluated the reduction in post-operative length of stay (LOS) that resulted from the fast-tracking protocol and assessed the potential cost saving in the case of nationwide implementation.Methods: A propensity score for fast-tracking was generated based on MCF liver transplant databases during 2011–2013. Various propensity score matching algorithms were used to form control groups from the United Network of Organ Sharing Standard Analysis and Research (STAR) file that had comparable demographic characteristics and health status to the treatment group identified in MCF. Multiple regression and matching estimators were employed for evaluation of the post-surgery LOS. The algorithm generated from the analysis was also applied to the STAR data to determine the proportion of patients in the US who could potentially be candidates for fast-tracking, and the potential savings.Results: The effect of the fast-tracking on the post-transplant LOS was estimated at approximately from 2.5 (p-value?=?0.001) to 3.2 (p-value?0.001) days based on various matching algorithms. The cost saving from a nationwide implementation of fast-tracking of liver transplant patients was estimated to be at least $78 million during the 2-year period.Conclusion: The fast-track program was found to be effective in reducing post-transplant LOS, although the reduction appeared to be less than previously reported. Nationwide implementation of fast-tracking could result in substantial cost savings without compromising the patient outcome. 相似文献
998.
Anna Batyra David de la Croix Olivier Pierrard Henri R. Sneessens 《The German Economic Review》2019,20(4):e38-e69
The rise of early retirement in Europe is typically attributed to the European system of taxes and transfers. A model with an imperfectly competitive labor market allows us to consider also the effects of bargaining power and of matching efficiency on pre‐retirement. We find that lower bargaining power of workers and declining matching efficiency have been important determinants of early retirement in France and Germany. These structural changes, combined with early retirement transfers and population aging, are also consistent with the employment and unemployment rates, labor share and seniority premia. 相似文献
999.
The propensity of the forecasts of sell-side financial analysts to converge (or diverge) is a function of their exogenous and endogenous selective attention and overconfidence. When returns are negative, the endogenous form of selective attention—a static measure of analysts’ goal-driven attention at a particular point in time—has a positive association with convergence. The exogenous form of selective attention—a relatively involuntary dynamic process of exogenous attentional shift driven by external changes in the market over time—is associated with a tendency for forecasts to diverge. 相似文献
1000.
唐梅芳 《安徽工业大学学报(社会科学版)》2006,23(3):47-49
“人的正确思想,只能从社会实践中来”是马克思主义辩证唯物论的认识论。只有坚持以实践为基础,坚持理论与实际相结合,才能获得完全的知识,形成正确的思想。 相似文献