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在万向减震球型钢支座的基础上对其弹簧元件进行耗能设计，提出了一种新型耗能减震球型钢支座，采用钢板弹簧叠加耗能钢作为耗能减震元件。通过单调拉伸加载试验和循环拉伸加载试验，研究了Q295钢材的耗能能力，采用拟静力试验和数值分析相结合的方法，分析了支座耗能减震元件的滞回性能和自复位性能；将该新型球型钢支座应用于网架结构中，考察其耗能减震能力。研究结果表明，Q295钢材的滞回曲线饱满，具有一定的耗能能力；减震元件的耗能减震性能较好，并且具有一定的复位能力；相较于一般的弹性减震支座，新型球型钢支座可以吸收部分地震能量，从而进一步降低结构的动力响应。

在减震球型钢支座的基础上，提出了一种新型功能分离型自复位耗能支座，其减震耗能组件由耗能钢元件与钢板弹簧元件以类似系杆拱的形式组成。本文采取试验与数值模拟相结合的研究方法分析其减震机理和减震效果，设计进行了耗能元件的LYP100钢材材料性能试验、板簧元件的刚度性能试验，同时对减震耗能组件进行了拟静力加载试验和数值模拟研究。研究结果表明，LYP100钢材滞回曲线饱满，耗能性能优良；钢板弹簧在横向荷载作用下工作性能稳定，可以为减震耗能组件提供稳定的刚度；在工作过程中，板簧元件始终保持弹性状态，实现支座的自复位功能，耗能元件在加载初期就进入塑性状态，实现塑性耗能。

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电负荷和热负荷具有较强的耦合性，热负荷需求的准确预测对于预测电负荷进而让供热机组更好地进行深度调峰辅助服务报价工作具有重要作用。经多种算法对比研究表明，基于最邻近结点和随机森林的集成预测算法（KNN-RFAverage）具有很好的回归性能和较低的计算复杂度。特别是在面对热负荷存在极端波动的情况下，采用该算法进行热负荷预测可以保持鲁棒性，为有效解决连续多点热负荷预测、机组供热面积及用热习惯发生变化的问题提供了新的思路和方法。

Copyright of Journal of Isotopes is the property of Journal of Isotopes Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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结合干式连接和湿式连接的优点提出了一种用于装配式钢筋混凝土柱(reinforced concrete,RC)的钢法兰-榫式连接,采用试验方法研究了该类连接的装配式RC柱的抗震性能。设计并制作了1个现浇柱试件和3个钢法兰-榫式连接的装配式柱试件,开展了试件的拟静力试验,研究了各试件的破坏过程及破坏形态,分析了钢法兰-榫式连接方式、钢法兰的钢腹板厚度及混凝土榫头箍筋配筋参数对试件破坏模式、滞回耗能性能、变形能力和关键点处应变的影响。试验结果表明,3个装配式试件的延性系数均大于4.0,变形能力和现浇试件相当,等效黏滞阻尼比均在0.2左右,表现出良好的延性及耗能性能;现浇试件XJ-1与装配式试件ZJ-1以柱底压弯破坏为主,装配式试件ZJ-2和ZJ-3分别发生腹板压弯破坏和榫头剪切破坏,试件ZJ-2的耗能能力较弱而试件ZJ-3的延性较差;腹板的厚度减小会降低钢节点的承载能力并导致腹板和上、下端板的应变增大,混凝土榫头箍筋配筋的减少导致榫头纵筋应变显著增加;装配式柱的柱纵筋的应变与现浇柱相当,表明钢节点能够有效传递纵筋应力。试验结果可为此类连接的装配式RC柱的设计提供参考。

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Objective To analyze the effects of watching short videos on the mental health of the middle-aged and elderly in China, to provide scientific basis for improving the mental health of the middle-aged and elderly. Methods Based on the data of China family panel studies (CFPS) in 2020, the linear regression model and propensity score matching method were used to explore the average effect of watching short videos on the mental health of the middle-aged and elderly. Results Watching short videos could significantly improve the mental health level of middle-aged people ( beta = - 0.217 . P < 0.05 ). Watching short videos had a more significant effect on women, rural areas, and middle-aged and elderly people with an education level of junior high school or below (women: beta = - 0.323 P<0.05; rural areas: beta = - 0.309 P<0.05; junior high school: beta=-0.387. P < 0.01; middle-aged people: beta = - 0.27 P<0.05). The nearest neighbor matching, radius matching, and kernel matching all passed statistical tests. Conclusion Watching short videos has to some extent improved the mental health of middle-aged and elderly people, and it is necessary to further increase the internet penetration rate of the elderly population and expand the coverage of smartphone usage training. Attention should be paid to the mental health of women, rural registered residence, middle-aged and elderly people with low education and income levels as well as physical diseases. [ABSTRACT FROM AUTHOR]

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The regeneration characteristics of Prunus armeniaca population under grazing disturbance were analyzed, and the relationship between natural regeneration in young plants and its influencing factors was discussed to provide a theoretical basis for optimizing grazing and protecting P. armeniaca resources in wild fruit forests. The wild fruit forests in Xinghuagou of Xinyuan County, Mohuergou of Gongliu County, and Daxigou of Huocheng County were selected as study sites where P. armeniaca are concentratedly distributed in Xinjiang. The grazing degree in the forest land was investigated by combining sample plots with sample lines of cattle tracks. The grazing intensity of each region was divided according to the disturbed degree of the herbaceous vegetation community(height, coverage, and aboveground biomass) in the forest land. The density, growth characteristics, and degree of damage of the naturally regenerated young P. armeniaca plants in each disturbance area were analyzed, and the relationship between the degree of damage in young plants and individual growth size(growing amount) as well as the habitat factors were discussed. The results showed that:(1) the density of natural regeneration in young P. armeniaca plants under light disturbance was the highest(364 tree·hm-2), followed by those of moderate disturbance(247 tree·hm-2) and heavy disturbance(225 tree·hm-2). The average regeneration density was 279 tree·hm-2.(2) The average ground diameter, crown width, tree height, inclination, and trunk height of the natural regeneration saplings of P. armeniaca under were 1.69 cm, 38.72 cm, 77.59 cm, 36.20°, and 35.75 cm, respectively. Significant differences were present in the growth indices under different grazing intensities, but no significant differences were present in the V age class.(3) The damage ratio of naturally regenerated young P. armeniaca plants reached a maximum of 84.48%. There were significant differences in the damage indices of naturally regenerated young P. armeniaca plants under light, medium, and heavy grazing disturbances, with damage indices of 38.52, 58.13, and 43.44, respectively.(4) Ordinal logistic regression analysis showed that the degree of damage to young plants after regeneration was significantly and negatively correlated with shrub coverage and grazing distance. The current grazing intensity of wild fruit forests severely hinders the natural regeneration of the P. armeniaca population. To maintain the sustainable management of wild fruit forests, it is necessary to optimize grazing systems and strengthen human intervention protection. [ABSTRACT FROM AUTHOR]

第十三届全国冬季运动会冰上运动中心——速滑馆钢屋盖采用张弦桁架结构形式。为了对体系的形成过程进行安全控制,采用大型通用有限元软件ANSYS对张弦桁架屋面结构进行了详细的施工仿真分析,确定出合理的张拉施工方案。重点介绍了交叉索索力及长度的确定、流水式预应力施工模拟分析及温度变化对张拉施工的影响分析。模拟分析和实测结果表明,提出的流水式预应力施工方案确保了结构施工过程的稳定与安全,同时结构成型态的预应力拉索索力和结构变形符合设计要求;一端张拉、一端固定的张拉形式可以减少设备的投入,实际张拉效果较为理想;交叉拉索预应力的确定原则较为合理,温度变化对张拉施工的影响较小,可以忽略。

【目的】探讨妊娠期糖尿病（GDM）孕妇不同血糖指标异常与甲状腺功能变化的关系。【方法】选择2014年1月 至2015年12月在中山大学附属第一医院东院规律产检并分娩妊娠期糖尿病孕妇212例，所有孕妇在孕24-28周均直接行 75 g OGTT。将仅一项血糖异常为GDMⅠ（116例），两项血糖异常为GDMⅡ（61例），三项血糖异常为GDMⅢ（35例）。以同 期在本院规律产检并分娩的1868例无内科合并症、产科并发症和甲状腺疾病高危因素的孕妇为对照组。所有研究对象均 在入院分娩时采集空腹血，分离血清后采用化学发光免疫法检测促甲状腺素（TSH）、游离甲状腺素（FT4）、甲状腺过氧化物 酶抗体（TPO Ab）水平。比较两组孕妇TSH、FT4、TPO Ab水平。分别采用方差分析、Mann-Whitney U检验、Kruskal-Wallis秩 和检验或Fisher精确概率法对数据进行统计学分析。【结果】GDMⅡ组孕妇TSH中位数呈升高趋势（P = 0.012），FT4中位数 呈降低趋势（P = 0.002）。GDMⅡ组亚临床甲状腺功能减退症患病率高于对照组，差异有统计学意义（P = 0.020）。GDMⅢ 组亚临床甲状腺功能减退症患病率高于对照组，差异有统计学意义（P = 0.013）。【结论】OGTT血糖异常项目数大于等于两 项的GDM孕妇甲状腺功能异常患病率增高，并以亚临床甲减最常见。临床应对此类孕妇进行甲状腺功能全面检测，及时 发现治疗甲状腺功能异常，确保孕期安全，改善妊娠结局。

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Cardiac autonomic dysfunction is a common complication after acute ischemic stroke (IS). Prior investigators have emphasized that infarction of brain stem or hemispheres with insular involvement is related to this dysfunction and may predict poor clinical outcome. From the viewpoint of stroke physicians, however, all stroke patients, particularly large-artery atherosclerosis (LAA) should be monitored for possible cardiac complications after acute IS. This study aimed to investigate cardiac autonomic impaction in patients with acute IS and to make the comparison between LAA and small-vessel occlusion (SVO) subtypes. Of the 126 acute IS patients prospectively enrolled in this study, 32 had LAA, 56 had SVO, and 38 had undetermined etiology according to the Trial of Org 10172 in Acute Stroke Treatment criteria. Cardiac autonomic function of all patients was assessed by measuring heart rate variability (HRV). The low- and high-frequency components of HRV in all stroke patients were significantly lower than those of control subjects after comparing multivariable models, including additional adjustments for age, gender, and all risk factors. There were no significant differences on HRV between LAA and SVO although post hoc comparisons showed that stroke patients of SVO had increased sympathetic modulation and reduced vagal activity. In conclusion, in acute IS patients, both LAA and SVO are predisposed to have cardiac autonomic dysfunction, manifesting as abnormalities in HRV, whether in hemispheric or brain stem lesions. Stroke patients of SVO are at higher risks of cardiac abnormalities, which might suggest an early cardiac dysfunction because of long-term hypertension. The HF component of HRV thought to be for vagal control might be a cardinal marker for predicting cardiac autonomic dysfunction after acute IS. Short-term HRV spectral analysis is a convenient approach for stroke clinicians to assess autonomic function in acute stroke. Long-term follow-up for HRV and clinical outcome relative to LAA and SVO stroke subtypes is warranted, particularly when an abnormal HRV is found at admission.

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【目的】通过对比分析合并陈旧性肺结核的非小细胞肺癌患者以CT为基础的淋巴结临床分期(N分期)和术后病理分期,探讨陈旧性肺结核对CT临床N分期的影响?【方法】 回顾性分析2007年10月至2010年8月在本中心接受根治性手术治疗的73 例合并陈旧性肺结核的非小细胞肺癌患者临床资料,对比CT临床N分期和术后病理分期的符合程度;并对CT常规所用的以形态学为主的预测指标(淋巴结直径?肿大淋巴结站数?淋巴结有无融合?淋巴结有无钙化)能否预测肺门纵隔淋巴结转移进行χ2 检验?【结果】 CT对非小细胞肺癌患者淋巴结转移预测的敏感性?特异性?阳性预测值?阴性预测值及准确性分别为61.1%?60.0%?33.3%?82.5%及60.3%,其中特异性(60.0%)明显低于文献报道中CT对非小细胞肺癌患者的总体评估(74% ~ 85%);在对合并有陈旧性肺结核的非小细胞肺癌患者肺门纵隔淋巴结的分站分析中,CT预测显示出较高假阳性率及较低的假阴性率;单因素分析结果显示CT常规的预测指标(淋巴结直径?肿大淋巴结站数?淋巴结有无融合?淋巴结有无钙化)与肺门纵隔淋巴结转移之间没有明显相关性?【结论】 陈旧性肺结核降低了CT预测肺门纵隔淋巴结状态的特异性,是影响CT对非小细胞肺癌患者N分期评估的重要影响因素?CT常规所用的以形态学为主的预测指标并不能有效预测肺门及纵隔淋巴结转移?