超声下肋锁间隙连续臂丛阻滞对手外伤术患者疼痛、应激反应及免疫功能的影响

目的 探讨超声下肋锁间隙(costo-clavicular space,CCS)连续臂丛阻滞对手外伤术患者疼痛、应激反应及免疫功能的影响.方法 选取102例手外伤手术患者作为研究对象,按照随机数字表法分为对照组(超声下喙突入路连续臂丛神经阻滞)和观察组(超声下肋锁间隙入路连续臂丛阻滞),每组51例,对比两组患者神经深度、麻醉操作时间、术后第1次追加药物时间、VAS评分、Cor、NE、CD3^(+)、CD4^(+)、CD8^(+)、CD4^(+)/CD8^(+)水平.结果 观察组患者的神经深度、麻醉操作时间及术后第1次追加药物时间均低于对照组(P<0.05).重复测量方差分析显示,两组患者VAS评分、Cor、NE、CD3^(+)、CD4^(+)、CD8^(+)、CD4^(+)/CD8^(+)水平存在时点、组间及时点与组间交互作用(P<0.05);术后6、12、24、48 h,观察组患者的VAS评分低于对照组(P<0.05).术毕、术后24 h,观察组患者的Cor、NE、CD4^(+)/CD8^(+)水平低于对照组,而CD3^(+)、CD4^(+)、CD8^(+)水平更高(P<0.05).结论 超声下肋锁间隙连续臂丛阻滞在手外伤术中具有较为理想的镇痛效果,利于减轻术后生理疼痛和机体应激反应,并对免疫功能影响更小.

U形钢板组合下肋空腹夹层板受力性能研究

采用8节点弹性块体有限元方法计算了一建筑平面为12m×12m的U形钢板组合下肋空腹夹层板楼盖结构,分析其在竖向荷载作用下的变形和内力特点,讨论了U形钢板组合下肋空腹夹层板的承载力设计问题,研究结论对类似工程的设计具有参考价值。

钢筋混凝土空腹夹层板空间结构的工程应用与计算方法

文章在介绍钢筋混凝土空腹夹层板的理论研究方法与主要技术特点的基础上,针对目前理论研究成果由于缺乏通用程序在工程运用中的局限性,探讨了该板柱结构体系在工程实践中的实用算法。通过工程实例论述了采用TAT三维空间杆系有限元分析软件时的模型处理办法,并提出了在设计与施工中应注意的问题。理论分析与实践表明,空腹夹层板楼盖体系属板片空间结构范畴,具良好的力学特性、建筑功能效应及技术经济指标。

中国科大北区学生食堂结构设计

本文重点介绍了空腹夹层板柱结构体系新技术在本工程中的运用及特点,探讨了在设计与施工中应注意的问题。本工程空腹夹层板结构设计为安徽地区首例,理论分析与实践表明,空腹夹层板楼盖体系具有良好的力学特性及技术经济指标。

大直径蜂窝型钢混组合空腹夹层板楼盖静力性能分析

蜂窝型钢混组合空腹夹层板是一种新型的三向受力的空间结构,其单元网格为造型独特的蜂窝状。本文通过有限元软件建立39.26m大直径圆形楼盖,主要施加竖向荷载进行静力分析。计算得出,楼盖扰度远低于规范限值,上肋梁内力受表层薄板的影响较大,轴力在靠近圆周处较大,且在同一节段内存在拉压内力反号现象;下肋梁轴力以受拉为主,剪力键是以剪切变形为主的块体。

对剖宫产术后的患者采用不同的入路进行腹横肌平面阻滞对其镇痛效果的影响

目的:探讨对剖宫产手术后的患者采用超声引导下肋缘下入路和超声引导下腋前线入路进行腹横肌平面阻滞对其镇痛效果的影响。方法:选取近年来在南充市中心医院进行剖宫产手术的46例患者作为本研究的对象。将这46例患者分为肋缘下入路组(L组)和腋前线入路组(Y组)。对两组患者均进行剖宫产手术。术后,对L组患者采用超声引导下肋缘下入路进行腹横肌平面阻滞,对Y组患者采用超声引导下腋前线入路进行腹横肌平面阻滞,然后比较两组患者术后各时间点的VAS评分、镇痛药物浓度达到峰值的时间、术毕至下床活动的时间及其对镇痛效果的满意率。结果:两组患者术后8 h、10 h、12 h、24 h及48 h的VAS评分相比差异无统计学意义(P>0.05)。两组患者镇痛药物浓度达到峰值的时间、术毕至下床活动的时间及对镇痛效果的满意率相比差异无统计学意义(P>0.05)。结论:采用超声引导下肋缘下入路和超声引导下腋前线入路对剖宫产手术后的患者进行腹横肌平面阻滞,均能取得良好的镇痛效果。

论歌唱的呼吸训练

歌唱的呼吸是决定歌唱技术水平高低的关键。歌唱的发声是气流振动声带而发音,这时声音很微弱,还需通过气流将声波传送到各共鸣腔,才能获得流畅、响亮、优美、园润而绚丽多彩的声音。

Analysis of the current rib support practices and techniques in U.S. coal mines

Design of rib support systems in U.S. coal mines is based primarily on local practices and experience. A better understanding of current rib support practices in U.S. coal mines is crucial for developing a sound engineering rib support design tool. The objective of this paper is to analyze the current practices of rib control in U.S. coal mines. Twenty underground coal mines were studied representing various coal basins,coal seams,geology,loading conditions,and rib control strategies. The key findings are:(1) any rib design guideline or tool should take into account external rib support as well as internal bolting;(2) rib bolts on their own cannot contain rib spall,especially in soft ribs subjected to significant load—external rib control devices such as mesh are required in such cases to contain rib sloughing;(3) the majority of the studied mines follow the overburden depth and entry height thresholds recommended by the Program Information Bulletin 11-29 issued by the Mine Safety and Health Administration;(4) potential rib instability occurred when certain geological features prevailed—these include draw slate and/or bone coal near the rib/roof line,claystone partings,and soft coal bench overlain by rock strata;(5) 47% of the studied rib spall was classified as blocky—this could indicate a high potential of rib hazards; and(6) rib injury rates of the studied mines for the last three years emphasize the need for more rib control management for mines operating at overburden depths between 152.4 m and 304.8 m.

A practical application of photogrammetry to performing rib characterization measurements in an underground coal mine using a DSLR camera

Understanding coal mine rib behavior is important for inferring pillar loading conditions as well as ensuring the safety of miners who are regularly exposed to ribs. Due to the variability in the geometry of underground openings and ground behavior, point measurements often fail to capture the true movement of mine workings. Photogrammetry is a potentially fast, cheap, and precise supplemental measurement tool in comparison to extensometers, tape measures, or laser range meters, but its application in underground coal has been limited. The practical use of photogrammetry was tested at the Safety Research Coal Mine, National Institute for Occupational Safety and Health(NIOSH). A commercially available, digital single-lens reflex(DSLR) camera was used to perform the photogrammetric surveys for the experiment. Several experiments were performed using different lighting conditions, distances to subject,camera settings, and photograph overlaps, with results summarized as follows: the lighting method was found to be insignificant if the scene was appropriately illuminated. It was found that the distance to the subject has a minimal impact on result accuracy, and that camera settings have a significant impact on the photogrammetric quality of images. An increasing photograph resolution was preferable when measuring plane orientations; otherwise a high point cloud density would likely be excessive. Focal ratio(F-stop) changes affect the depth of field and image quality in situations where multiple angles are necessary to survey cleat orientations. Photograph overlap is very important to proper three-dimensional reconstruction, and at least 60% overlap between photograph pairs is ideal to avoid unnecessary post-processing. The suggestions and guidelines proposed are designed to increase the quality of photogrammetry inputs and outputs as well as minimize processing time, and serve as a starting point for an underground coal photogrammetry study.

检查肉牛肥度的方法

(一)检查下肋 以拇指插入牛的下肋侧壁,其余4指并拢,贴靠在肋的外侧壁,虎口紧贴在下肋的边缘。这样用手触摸其厚度和弹性,厚度越厚,弹性越强,说明牛体越肥。 (二)检查颈部 检查者站在牛体左侧颈部附近。