浅述碱-骨料反应对混凝土耐久性的影响及预防措施

碱骨料反应对混凝土耐久性有极大的危害,本文就碱骨料反应的机理、产生条件、破坏特征、骨料碱活性的测定和如何预防进行了阐述。     

玉竹根腐病的发生与防治

在玉竹的栽培生产中,病害大量发生,其中最为严重的是根腐病。玉竹根腐病是由镰刀菌引起的一类土传病害,近年在湖南、广东老栽培区域有逐年加重的趋势。分析其危害症状和发生特点,可对其采取合理轮作、栽培措施防治、土壤消毒、药剂防治等综合防治措施,以促进玉竹的产量和品质。     

OPGW光缆断股的分析及处理

通过一起OPGW光缆外层绞线断股现象,分析了其形成的机理和产生的原因,得出了外层采用铝合金单丝时在雷击情况下易产生外层断股的结论,并从设计、施工、运行等方面提出了具体的防范措施。     

The association between perceived injunctive norms toward corporal punishment,parenting support,and risk for child physical abuse

The use of corporal punishment (CP) is a strong risk factor for many poor outcomes for children including child maltreatment. The use of CP occurs within social contexts which are important to understand. Although it is known that perceived social norms regarding CP are related to its use, the specific role that a mother’s primary support person plays in influencing attitudes toward and use of CP remains unknown. The current study assessed linkages between maternal perceived social support in parenting and perceived injunctive norms of CP from her primary source of support, with maternal attitudes toward and use of CP. Survey data were collected from female primary caregivers (N = 436) of children age 2 to 7 years (mean age = 3.7) enrolled in Special Supplemental Nutrition Program for Women, Infants and Children (WIC) clinics in Southeastern Louisiana. Most frequently, the biological father of the child (37.9%) and the maternal grandmother of the child (24.2%) were identified as the participant’s primary source of social support in parenting. Perceived injunctive norms of this support person toward CP use were significantly and positively associated with attitudes toward, AOR = 5.97, 95% CI = [4.04, 8.82], and use of CP, AOR = 3.77, 95% CI = [2.55, 5.59]. However, perceived social support was not associated with these outcomes and also did not moderate these associations. Findings suggest that efforts to reduce maternal risk for child physical abuse and use of CP must include the mother’s primary source of social support if they are to be successful.     

千阳县山洪灾害防治非工程措施初探

根据千阳县的实际情况,提出了建立监测预警设施、监测预警平台、防御转移预案、组织责任体系、宣传培训演练等非工程措施,实现预警及时、反映迅速、转移快捷、避险有效,全面提高山洪灾害防御水平。     

CSSD护士的职业危害与防护对策相关性研究

医院消毒供应中心(CSSD)是集中全院污染的医疗用品及敷料的部门。长期与致病源、锐器、噪音、化学消毒液、高温、电器辐射、潮湿等因素接触,对CSSD员工的健康和安全产生了威胁。本文分析了CSSD的职业危害因素,并提出职业防护对策,以期提高自我防护水平,减少危害,避免发生医疗不良事件,促进CSSD护理人员的职业健康。     

简论我国新闻人才观的变迁

“通才办报”、“史家办报”、“政治家办报”是中国新闻人才观中最具代表性的理论。这三种理论的侧重点虽各有不同,但相互之间却有着一定的联系。它们对于培养当时的新闻从业者发挥了各自的作用,对今天的新闻工作仍然有指导和借鉴意义。     

Sex differences in elbow and wrist joint loading during the cartwheel and round off with different hand positions performed by young gymnasts

The aim of the study was to determine if sex differences exist in the key elbow and wrist joint injury risk factors during different cartwheel (CW) and round-off (RO) techniques performed by young male and female artistic gymnasts. Sixteen active young gymnasts (8 males and 8 females) performed 30 successful trials of CW and RO with three different hand positions (parallel (10), T-shape (10) and reverse (10)). Synchronised kinematic and kinetic data were collected for each trial. Two-way repeated measures ANOVA (3 × 2, technique × sex) and effect-sizes (ES) were used for statistical analysis. In conclusion, female gymnasts exhibited greater normalised peak vertical ground reaction forces (VGRF), elbow and wrist compression forces and elbow internal adduction moments during CW and RO skills compared with male gymnasts. In both sexes, the parallel and reverse techniques increased peak VGRF, elbow and wrist compression forces and the elbow internal adduction moment. Increased elbow flexion resulted in decreased peak VGRF, elbow compression forces and elbow internal adduction moment. Injury risk factors including elbow extension and internal adduction moment with axial compression force suggest that a CW and RO in reverse and parallel techniques can be hazardous especially for young female gymnasts.     

Between-limb differences in running technique induces asymmetric negative joint work during running

Negative work, which is mainly generated by eccentric muscle contraction, has an important influence on the associated muscle damage. Generally, mechanical parameters are determined for one side of a lower extremity on the assumption of negligible between-limb differences. However, between-limb differences in the negative work of lower extremity joints during running remain unclear. This study examines between-limb differences in negative work and associated mechanical parameters during the contact phase of running. Twenty-five young adult males voluntarily participated in this study. Each participant was asked to run on a straight runway at a speed of 3.0?m?s^?1. Negative work, amplitude, duration of negative power, moment, and angular velocity were computed for both sides of the lower extremities. Significant differences were found in negative work between limbs for the hip (18.9?±?11.7%), knee (13.6?±?10.4%), and ankle (11.8?±?8.5%) joints. For the hip joint, asymmetric negative work was attributable to the between-limb difference in the amplitude of negative power owing to a corresponding difference in the moment. The between-limb differences concerning the duration and amplitude of negative power could explain the asymmetric negative work in the knee joint. The asymmetric negative work of the ankle joint was attributable to the between-limb difference in the amplitude and duration of the negative power and the moment. These results indicate that asymmetric negative work was generated in each lower extremity joint; however, the major mechanical parameters corresponding to the negative work are not the same across the joints.     

东京奥运会延期举办背景下东道主形象修复策略研究

新冠疫情对东京奥运会各项筹办工作和东道主形象产生了负面的影响,日本方面因时而变、因势利导,积极引导国际舆论走向,维护奥运会东道主的良好形象。东京奥运会延期举办事件的决策过程经历了4个发展阶段,对东京奥运会延期举办背景下各方定义的新闻议程进行了分析,结合新闻议程内容对奥运会东道主形象修复策略展开了研究。日本方面根据全球疫情变化、本国疫情防控形势和国际舆论走向,针对不同的发展阶段,采取了建立信心、推卸责任、拖延、诚意等形象修复策略,试图强化人们对于东京奥运会东道主安全条件的形象认知,致力于维护日本"安全之手"的国际形象,增强世界各国对于东京奥运会顺利举办的信心,在危机应对中实现国家利益最大化,其中不乏成功经验值得借鉴参考。