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241.
基于中泰两国地缘差异性及资源禀赋互补优势,双边水果贸易合作发展取得了令人瞩目的成效,贸易总量持续增长,贸易地位日益凸显,成为两国经贸合作的重要内容.中泰水果贸易合作中仍存在着:水果种类单一、深精加工有限、附加值较低、互补优势尚未充分挖掘、贸易便利化水平不高、国际与地区竞争激烈等突出问题.在打造中国—东盟自贸区“升级版”新形势下,中泰两国应充分立足互补性优势,构建水果商品贸易信息合作平台,增强宣传与培育特色品牌,完善运输渠道与减低物流费用,挖掘国内潜在市场,促进双边水果贸易合作取得更大的成效.  相似文献   
242.
习近平在世界互联网大会上的主旨讲话中指出,互联网把世界变成了“鸡犬相闻”的地球村,改变着人们的生产生活,有力推动了社会发展;同时,他又指出,网络空间不是“法外之地”,并明确提出了加强网络空间治理、规范网络空间行为等要求.网络的虚拟性、开放性和交互性,既给人们提供了自由的空间和舞台,又对人们的道德要求和责任担当提出了更高的要求.行为主体网络信息的自由表达有其必要的边界和限度,网络行为中的责任担当对规范网络空间和现实社会的有序发展存在着积极的应然价值,自由与责任构建了网络空间最基本的伦理诉求.  相似文献   
243.
文章考察了美国博物馆的青少年教育的概况和具体形式,认为美国博物馆的青少年的开始时间早,教育形式不但多样,而且契合青少年的年龄特点,取得了较好的成效。我国博物馆的青少年教育在教育理念、形式做法、实际效果等方面都与美国博物馆存在着不小的差距,需要进一步向美国博物馆学习。  相似文献   
244.
ABSTRACT

Drawing on digitaltrace data, publicly accessible government documents, and journalistic reports, this research integrates Beck’s risk society theory with digital media theories to examine the mediated process of risk definition and assessment of PM2.5 (particulate matters with a diameter less than 2.5 micrometers) in a networked public sphere. Network and content analysis of a PM2.5 Twitter network shows that political and professional elite remained the most powerful producers of risk definition. Established media played a key role, yet faced challenges from a variety of actors who disseminated and filtered information. Laypersons, while peripheral, actively interacted with elite and established media. The blurring geographic boundary in the PM2.5 Twitter network revealed an emerging transnational public sphere, which, however, was segregated by language. This research advances a layered understanding of the contingent, paradoxical media impact for social changes in a risk society.  相似文献   
245.
Objective: To analyze the impact of age, BMI and sex hormone on aging males’ symptoms (AMS) and the 5-item version of the international index of erectile function (IIEF-5) scores in middle-aged and elderly Chinese men.

Methods: A population-based cross-sectional study was conducted in Jiashan County. A total of 969 men, aged between 40 and 80 years old, were admitted. Physical examination and the sex hormones were measured, and AMS and IIEF-5 scores were assessed.

Results: The oneway ANOVA analysis indicated older age groups had higher AMS total-scores, somatic and sexual sub-scores, and lower IIEF5 scores (all p?rpairwise) analyses showed the significant associations between AMS and age or sex hormone (cFT, Bio-T, SHBG, and LH) levels, and similar for IIEF5. However, when age was adjusted, the correlation coefficients (rpartial) weakened, and correlation significance disappeared, except LH (for AMS: rpartial?=?0.096, p?=?.009; for IIEF-5: rpartial?= ?0.140, p?=?.001). Multiple linear regressions confirmed the influence of increased age and LH on the AMS and IIEF5 scores.

Conclusion: CFT, Bio-T and SHBG failed to yield any additional predicting information when age was adjusted. To improve the male reproductive health, future research should pay more attention on aging-related comorbidities and how to improve general wellness.  相似文献   
246.
This study aims to investigate school counselors’ competency level in working with lesbian, gay, bisexual, transgender (LGBT) youth. Using a sample of 125 school counselors who are currently practicing in schools, this study found school counselors perceived themselves with very low competency levels. Spearman's rho correlation results indicated that only three demographic variables were significantly correlated with school counselors’ self-perceived competency level: sexual orientation, whether having received any postmasters trainings and geographic regions. Counselors identifying as nonheterosexual, those who received postmasters trainings or workshops, and those who reside in the West tend to have a higher self-perceived competency working with youth identifying as LGBT.  相似文献   
247.
随着城市化进程的不断推进、建设用地不断扩张,城市生态空间正处于剧烈变化中。大量具有生态价值和服务功能的土地不断被侵占,以满足暂时的城市建设需求。但从长远来看,这些生态用地的"消失",将不可避免的影响区域生态平衡,给区域经济的健康发展埋下隐患。广州作为华南的中心城市,改革开放以来,大量外来人口涌入,土地利用变化频繁,生态环境的保护面临着巨大压力。因此,本文基于多源遥感数据,利用监督分类法与综合指数法相综合的复合提取方案对2016年广州生态用地进行空间识别,掌握广州市生态用地存量现状。同时,借助生态风险小区和生态风险等景观指数对广州进行了生态风险评估,结果显示,广州市生态风险呈现明显的多核圈层结构,由多核心的中心向外部逐渐降低。  相似文献   
248.
In this paper, we investigate the precise large deviations for sums of φ-mixing and UND random variables with long-tailed distributions. The asymptotic relations for non random sum and random sum of random variables with long-tailed distributions are obtained.  相似文献   
249.
Parametric and semiparametric mixture models have been widely used in applications from many areas, and it is often of interest to test the homogeneity in these models. However, hypothesis testing is non standard due to the fact that several regularity conditions do not hold under the null hypothesis. We consider a semiparametric mixture case–control model, in the sense that the density ratio of two distributions is assumed to be of an exponential form, while the baseline density is unspecified. This model was first considered by Qin and Liang (2011 Qin, J., Liang, K.Y. (2011). Hypothesis testing in a mixture case–control model. Biometrics 67(1):182198.[Crossref], [PubMed], [Web of Science ®] [Google Scholar], biometrics), and they proposed a modified score statistic for testing homogeneity. In this article, we consider alternative testing procedures based on supremum statistics, which could improve power against certain types of alternatives. We demonstrate the connection and comparison among the proposed and existing approaches. In addition, we provide a unified theoretical justification of the supremum test and other existing test statistics from an empirical likelihood perspective. The finite-sample performance of the supremum test statistics was evaluated in simulation studies.  相似文献   
250.
郑方辉  卢扬帆 《学术研究》2012,(4):82-88,160
过去30年中国经济发展所取得的成绩举世瞩目,但生态环境污染日趋加剧亦成为不争的事实.作为中国现代化的缩影,1980-2010年,广东每增加1%的工业产值,日照时间减少0.3852小时.抽样调查的结果显示:目前广州、深圳等珠三角城市的日照时数已降至接近公众期望的临界值.遏制此种态势,转变经济发展模式固然重要,但更为重要的在于物欲的“零增长”.要做到这一点,日照时数应成为政府环保绩效评价的重要指标.  相似文献   
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