菱角壳的化学成分和药理活性研究进展

近年来对菱角壳的研究主要分为化学成分和药理活性研究两个方面,其中化学成分方面的研究可以概括为生物碱、酚酸类、萜类和甾体、多糖类、黄酮类5个方面;药理活性方面的研究可以概括为抗癌活性、抗氧化活性、降低α-葡萄糖苷酶活性、保肝护肝活性、抗菌活性5个方面。目前在化学成分方面的研究较弱,从研究结果来看,没食子酸及其衍生物是菱角壳的主要药用成分。最后就菱角壳的开发利用提出了几点建议。     

Analyst Herding and Stock Price Crash Risk: Evidence from China

We examine the proposition that firms with disproportionately more analysts herding in their coverage, as measured by a larger herding index value, have higher crash risk. Our findings are consistent with the main proposition. The results suggest that information production, rather than monitoring, is the primary mechanism behind the positive relation between herding and crash risk. Our conclusion is robust to different measures of crash risk, crash risk windows, herding measures, subsamples, and instrumental estimation. In addition, using post‐earnings announcement drift, we report that analyst herding slows down bad news transmission in the market. Our findings extend the literature by documenting that analyst herding plays a role in enhancing crash risk. Analyst herding has economic consequences on the covered firms. We offer support for the concern in the literature regarding analyst herding and market fluctuations.     

Inflation and inflation uncertainty in China

The study examines the relationship between inflation and inflation uncertainty in China using Generalized Autoregressive Conditional Heteroscedasticity model. Particularly, this link is investigated in China’s urban and rural sectors, motivated by the substantial urban–rural divide. The results provide strong statistical supportive evidence that higher inflation raises inflation uncertainty. On the other hand, evidence on the effect of inflation uncertainty on inflation is mixed depending on the sample periods and areas examined. The understanding of inflation-uncertainty nexus in China could provide implications to policymakers in the adoption of monetary policies.     

教育本该不一样

教育本该不一样，因材施教、有教无类，说的就是不同。教育不从根本上由“批发”改为“零售”，我们就培养不出创新人才、杰出人才，甚至于培养不出我们常说的有用人才。为了培养创新人才，教育内容要力求全面，教育目标要力求明确，教育的方法要务求得当。     

Efficiency of New Zealand’s District Health Boards at Providing Hospital Services: A stochastic frontier analysis

Journal of Productivity Analysis - The majority of secondary and tertiary healthcare services in New Zealand are provided through public hospitals managed by 20 local District Health Boards. Due to...     

深度休闲对主观幸福感的影响研究——以苏南地区城市居民为例

深度休闲对优化苏南地区休闲产业建设,进一步提升居民休闲生活质量有重要影响。文章通过问卷调查的方式收集苏南地区城市居民深度休闲行为的数据,研究苏南地区城市居民深度休闲行为特征及深度休闲对主观幸福感的影响。结果发现:(1)苏南地区城市居民进行深度休闲活动的场所主要为户外;(2)闲暇时间不足是限制苏南地区城市居民进行深度休闲活动的主要因素;(3)苏南地区城市居民的深度休闲活动总体程度不高,愿意在深度休闲活动上投入大量时间和金钱的人更是少数;(4)苏南地区城市居民从事深度休闲活动产生的强烈认同感和坚持不懈的毅力对主观幸福感有着显著的积极影响。     

Object detection based on visual memory: a feature learning and feature imagination process

ABSTRACT

Visual memory plays an important role for the human’s visual system to detect objects. The features of an object stored in the visual memory have much lower dimensions than the features contained within an image. We simulate the visual memory as a feature learning and feature imagination (FLFI) process to build an object detection algorithm. The method is constructed by a bottom-up feature learning and a top-down feature imagination. The proposed object detection method is tested using publicly available benchmark data sets, and the result indicates that it is fast and more robust.     

The capital market spillover effect of product market advertising: Evidence from stock price synchronicity

We analyze whether product market advertising has a spillover effect on stock price synchronicity by transmitting firm-specific information to the capital market and attracting more investor attention. Using a sample of Chinese listed firms from 2009 to 2017, we find that firms with greater advertising expenditures have lower stock price synchronicity. The results are robust after we address endogeneity concerns. In accord with our hypothesis that product market advertising increases the amount of firm-level information capitalized into stock prices through the information channel, we find that the impact of advertising on synchronicity is more pronounced for firms with a higher degree of information asymmetry and firms in the consumer-product industry. Further tests show that product market advertising enhances the ability of current period returns to reflect future earnings, and thus rules out that the negative relationship between advertising and synchronicity is driven by noise trading. Our results imply that product market advertising plays an informative role and improves information efficiency in a capital market.     

Turning corporate environmental ethics into firm performance: The role of green marketing programs

In this study, we develop a better understanding of the mechanisms by which corporate environmental ethics influences performance through the adoption of substantive actions. The empirical results of a moderated mediating analysis show that firms with higher environmental ethics are more likely to implement green marketing programs, consisting of the green production, pricing, distribution, and promotion programs and then improve firm performance. It is also observed that closure mechanism negatively moderates the mediation effect of green marketing programs because it leads to low trust and unwillingness to internal cooperation. These findings indicate that the value of corporate environmental ethics could not be determined in a vacuum, both strategy and people do matter when pursuing environmentally driven performance.