Impact of metabolic status on the association of serum vitamin D with hypogonadism and lower urinary tract symptoms/benign prostatic hyperplasia

Objective: The objective of this study is to investigate the impact of metabolic status on associations of serum vitamin D with hypogonadism and lower urinary tract symptoms (LUTS)/benign prostatic hyperplasia (BPH).

Patients and methods: A total of 612 men underwent physical examination, biochemical/hormonal blood testing, and transrectal prostate ultrasound. Moreover, the subjects filled out standard questionnaires for identification and grading of LUTS and hypogonadism symptoms. Parameters were statistically compared with independent t-tests and correlation analyses.

Results: Vitamin D levels positively correlated with total testosterone (TT) but not with prostate volume or International Prostate Symptom Score (IPSS). Patients with metabolic syndrome had significantly lower vitamin D levels, which were not correlated with TT, prostate volume, or IPSS. However, vitamin D was positively correlated with TT, and negatively correlated with prostate volume and quality-of-life IPSS in subjects without metabolic syndrome.

Conclusion: The clinical usefulness of vitamin D for treatment of hypogonadism or LUTS/BPH varies according to metabolic status.     

现代油画中北朝壁画的表现性因素探析

文章认为中国表现主义艺术源远流长、资源丰厚,探掘与梳理西域北朝壁画中表现主义资源,对中国当代油画发展与北朝壁画中表现性资源的构建充满意义,此维度的研究将更加有效地推动中国表现主义油画的发展。     

Left Behind by Parents in China: Internal Migration and Adolescents’ Well-Being

This study investigates how growing up as a left-behind child due to parents’ labor migration in China is associated with adolescents’ cognitive and socioemotional development, based on data from the China Family Panel Studies. We find that adolescents do worst when both parents are absent in all developmental indicators we examined: short-term and long-term word recall tests, numeracy test, self-concept, and self-expectation of educational attainment. However, the differences between left-behind children and those in rural two-parent families are not statistically significant. Left-behind adolescents do have significantly lower well-being than those in urban two-parent families. These differences can largely be accounted for by father's education, family spending on the adolescent's education, quality of parenting, and the social support available to an adolescent. The gap in Chinese adolescents' development is, thus, not so much related directly to how many parents one grows up with as it is to whether one grows up in a rural or urban environment.     

Mangrove forests store high densities of carbon across the tropical urban landscape of Singapore

Tropical forested ecosystems provide multiple ecosystem services to rural and urban landscapes, with carbon storage gaining particular attention. Deforestation due to rural-urban transitions may lead to a reduction in carbon storage ability. Coastal mangrove forests are particularly at risk from deforestation due to their location in the rapidly urbanizing coastal zone, and the city state of Singapore is an extreme example, losing as much as 90 % of its original mangrove cover due to land reclamation and reservoir construction. Knowledge of mangrove ecosystem services may allow better conservation, restoration and incorporation of remaining mangrove patches into the urban landscape. Focusing on the regulating ecosystem service of carbon storage, mangrove carbon stocks have been estimated for Singapore using a combination of field and remote sensing techniques. Biomass carbon showed substantial spatial variation, with old, contiguous mangrove patches containing a higher density of biomass carbon than fragmented, river-fringing or restored mangroves. In total, national biomass carbon equated to 116,117.1 megagrams of carbon (Mg C), and a coarse estimate of the total carbon stock (including soil carbon) suggests that Singapore’s mangroves may store 450,571.7 Mg C. While lower than other regional estimates focused on natural, oceanic mangroves, this is a significant carbon stock for a disturbed, urban mangrove system, and may be equivalent to the average annual carbon emissions of 621,000 residents. This analysis, alongside a review of other urban forest studies, highlights the importance of forested ecosystems such as mangroves in providing a carbon storage ecosystem service to urban areas.     

滇越边民跨国流动与社会稳定研究——基于国家、地方与边民的视角

血缘关系使滇越边民频交簌往在中越两国边境,影响着国家疆域的巩固和边疆民族社会秩序的稳定。国家安边守土的治国思路,使边民得到惠施的同时,也为边商创造了跨境从商的机会。边商的边境从商行为又为两地边民务工创设下良好环境,进而泛化滇越边民的跨国越境行为,滇越边境的正常社会秩序面临更大挑战。维稳滇越边境关键在于国家、地方和边民三者之间构织起一个有序的会通和并接环境。     

构建和谐民族地区的社会保障制度建设探讨

民族地区现行社会保障制度尚不健全、覆盖面小、整体水平低、管理不规范、立法滞后,与全面建设小康社会、构建社会主义和谐社会和建设社会主义新农村的需求不相适应。构建和谐民族地区的社会保障制度,则应坚持以科学发展观为指导,坚持从各族群众迫切需要解决的领域建立健全社会保障制度,统筹社保体系完善与资本市场培育,构建社会统筹与个人账户相对独立的新型关系,建立健全社会保障基金保值增值长效机制,坚持农村与城市社会保障制度统筹建设、协调推进,进一步重视提高社会保障制度的运行效率,积极推进社会保障制度和措施的法制化。     

凹型收益率曲线与中等教育投资"瓶颈":对童工的另一种解释

对于童工问题,以往的研究大多以童工本人或其家庭、学校和市场环境作为分析对象,强调贫困对儿童教育的伤害,忽视了教育本身对于受教育者的经济意义,尤其是教育作为一种人力资本投资在经济上的合理性.本文的分析表明,对落后地区的家庭而言,由于中等教育阶段的成本增加而收益下降,使得其收益率较低,缺乏投资上的吸引力,进而导致失学和童工问题.鉴于问题的复杂性,必须将各种法规和措施结合在一起,综合治理,降低贫困家庭中等教育的成本,才有可能突破这一"瓶颈",最终减少和消除童工.     

大学生犯罪情况、原因及防范研究——基于近五年550例裁判文书的统计分析

通过对近5年大学生犯罪案件裁判文书的梳理发现:大学生犯罪数量呈上升趋势,犯罪案件类型广泛、多元,犯罪已经不再局限于几种罪名;大学生犯罪被判处刑罚多为6个月以上3年以下有期徒刑,但也不乏重刑.大学生涉嫌犯罪的原因主要有:大学生家长犯罪,而大学生未能制止并参与;对违法犯罪后果的严重性认识不足被他人利用;和他人发生争执不能妥...     

食品安检专业开设动物病理学课程的改革与探索

本文从专业现状及教学中存在的问题,对食品安检专业开设动物病理学课程的教学改革相关问题进行阐述,为全面培养高素质的食品安检专业人才提供经验。     

An elastic-net penalized expectile regression with applications

To perform variable selection in expectile regression, we introduce the elastic-net penalty into expectile regression and propose an elastic-net penalized expectile regression (ER-EN) model. We then adopt the semismooth Newton coordinate descent (SNCD) algorithm to solve the proposed ER-EN model in high-dimensional settings. The advantages of ER-EN model are illustrated via extensive Monte Carlo simulations. The numerical results show that the ER-EN model outperforms the elastic-net penalized least squares regression (LSR-EN), the elastic-net penalized Huber regression (HR-EN), the elastic-net penalized quantile regression (QR-EN) and conventional expectile regression (ER) in terms of variable selection and predictive ability, especially for asymmetric distributions. We also apply the ER-EN model to two real-world applications: relative location of CT slices on the axial axis and metabolism of tacrolimus (Tac) drug. Empirical results also demonstrate the superiority of the ER-EN model.