Investigation on Residual Strength and Failure Mechanism of the Ceramic/UHMWPE Armors after Ballistic Tests

In this paper, the ballistic damage mechanism and residual bearing capacity of ceramic/backing plate armor were investigated. First, a series of lightweight armors were prepared, consisting of ceramic and ultra-high molecular weight polyethylene fiber-reinforced resin matrix composite (UHMWPE) plates, and were wrapped in a high-strength fabric. Then, the ceramic/UHMWPE armors were hit by one or two bullets, and finally subjected to compression testing. The results showed that the main failure mode of integral ceramic/UHMWPE armors was ceramic brittle fracture. Many zigzag patterns on the compression curve indicated that the specimens had undergone the stages of crack propagation, ceramic fragment reorganization, plastic deformation of UHMWPE backing plate, interlaminar tearing, and overall fracture. The failure of spliced ceramic/UHMWPE armors was mainly due to the dislocation between ceramic sheets; the smooth compression curves indicated that there was no recombination of ceramic fragments and obvious interlayer debonding during the compression. Under the maximum load, each ceramic/UHMWPE armor with ballistic damage did not suddenly break and fail. The structure and thickness of ceramic plates all had an impact on residual strength: under the same structure, the greater the thickness, the greater the residual strength, but the relationship between them was not linear; under the same thickness, the residual strength of the spliced ceramic/UHMWPE armor was higher. The residual strength was also related to the number of shots: after two bullets hit, its value was only one-third of that after one bullet hit.     

椎体成形术联合补肾健骨汤治疗老年骨质疏松性压缩骨折的临床效果

目的:分析椎体成形术联合补肾健骨汤治疗老年骨质疏松性压缩骨折的临床效果。方法:选择2016年9月-2019年4月本院收治的73例老年骨质疏松性压缩骨折患者,按随机数表法分为两组,对照组(36例)采用椎体成形术治疗,研究组(37例)在对照组的基础上加用补肾健骨汤治疗,对比两组临床效果、腰椎功能及疼痛度。结果:研究组治疗总有效率94.59%(35/37)比对照组高(P<0.05);研究组腰椎功能评分(16.36±1.69)分,明显比对照组优(P<0.05);研究组治疗后腰椎疼痛度为(3.13±0.23)分,明显比对照组低,差异具有统计意义(P<0.05)。结论:老年骨质疏松性压缩骨折采用椎体成形术联合补肾健骨汤治疗,可减轻疼痛度,改善腰椎功能,还能提高治疗效果,值得临床推广。     

补肾壮骨汤对骨质疏松型胸腰椎压缩骨折患者椎体成形术治疗效果影响的Meta分析

[目的]采用Meta分析法系统评价补肾壮骨汤对椎体成形术治疗骨质疏松型胸腰椎压缩骨折(OTCF)临床的影响。[方法]以"补肾壮骨汤"为首输关键词,以"椎体成形术""骨质疏松""胸腰椎压缩骨折"等为次输关键词,全面搜索补肾壮骨汤对OTCF患者椎体成形术治疗效果影响的随机对照研究文献,评价纳入研究文献的一般特征,对文献资料所提取的治疗有效率、骨密度、Oswestry功能障碍(ODI)指数、治疗安全性(新发骨折率)等观察指标进行Meta分析处理与分析。[结果]共13篇文献纳入Meta分析范畴,文献总样本量1 037例。分析显示,与对照组相比,治疗组可明显提高临床有效率[OR=4.63,95%CI[2.92,7.36],P0.000 01]、改善骨密度[MD=0.08,95%CI[0.06,0.1],P0.000 01]、降低ODI指数[MD=-2.34,95%CI[-3.49,-1.19],P0.000 01]、降低新发骨折率[OR=0.08,95%CI[0.11,0.44],P0.000 01]。[结论]与单纯椎体成形术治疗相比,补肾壮骨汤辅助椎体成形术在OTCF患者治疗中,可提升患者术后骨密度、改善胸腰椎功能障碍和降低术后新发骨折率,治疗疗效确切。     

独活寄生汤治疗骨质疏松性椎体压缩骨折的临床效果

目的：探讨独活寄生汤对骨质疏松性椎体压缩骨折（OVCF）患者高迁移率族蛋白-1（HMGB-1）、C反应蛋白（CRP）、降钙素原（PCT）的影响。方法：选取2015年4月至2016年9月广州中医药大学第二附属医院收治的OVCF患者92例作为研究对象,按照随机数字表法随机分为对照组和观察组,每组46例。2组均行经皮椎体后凸成形术治疗,对照组给予常规处理,观察组在此基础上加用独活寄生汤,2组均治疗2周。比较2组术后2周的骨折愈合情况、股骨颈骨密度及日本骨科协会腰痛评价表（JOA）评分,术前、术后3 d的炎性反应递质水平,术后1、3、7 d的疼痛视觉模拟评分（VAS）。结果：与术前比较,术后2周,2组伤椎前缘高度、股骨颈骨密度及JOA评分均升高,且观察组高于对照组,差异有统计学意义（P<0.05）;2组伤椎楔变角及后凸Cobb角均降低,且观察组低于对照组,差异有统计学意义（P<0.05）;术后3 d,2组血清TNF-α、CRP、PCT及HMGB-1水平均升高,且观察组低于对照组,差异有统计学意义（P<0.05）。与术后1 d比较,术后3、7 d,2组VAS评分均降低,且观察组低于对照组,差异有统计学意义（P<0.05）。结论：采用独活寄生汤治疗OVCF,可降低患者炎性反应递质水平,减轻疼痛,并可改善患者骨质疏松症状,促进骨折愈合,疗效显著。     

彩色超声引导下针刀治疗肩胛上神经卡压综合征临床疗效观察

目的:观察彩色超声引导下针刀治疗肩胛上神经卡压综合征的临床疗效。方法:选择本院治疗的肩胛上神经卡压综合征患者60例,随机分为观察组和对照组,每组30例。对照组给予小针刀松解治疗,观察组在彩色超声引导下给予小针刀松解治疗。结果:观察组有效率96.7%,对照组有效率86.7%,观察组高于对照组,差异有统计学意义(P<0.05);治疗1周后、1个月后随访,两组VAS评分均低于治疗前,且观察组低于对照组,差异有统计学意义(P<0.05);治疗1周后、1个月后随访,两组Constant-Murley肩关节评分均高于治疗前,且观察组高于对照组,差异有统计学意义(P<0.05)。结论:彩超引导下针刀局部松解治疗肩胛上神经卡压综合征,可减轻患者的疼痛,缩短肩关节活动功能恢复的时间。     

滋肾续骨汤联合鲑鱼降钙素对老年椎体压缩性骨折术后血清骨形态发生蛋白9及血管内皮生长因子水平的影响

目的观察滋肾续骨汤联合鲑鱼降钙素对老年椎体压缩性骨折术后血清骨形态发生蛋白9(BMP9)及血管内皮生长因子(VEGF)水平的影响。方法将80例老年椎体压缩性骨折术后患者按照随机数字表法分为2组。对照组39例予鲑鱼降钙素治疗;治疗组41例在对照组治疗基础上加用滋肾续骨汤治疗。2组均治疗24周后统计临床疗效,并观察2组治疗前后血清BMP9、VEGF水平及疼痛视觉模拟评分(VAS)、胸腰椎损伤分类及损伤程度评分系统(TLICS)、Oswestry功能障碍指数(ODI)评分、日本骨科协会(JOA)腰痛评分,以及椎体前缘丢失高度、伤椎Cobb角、伤椎骨密度水平及并发症发生情况。结果治疗组总有效率95.12%(39/41),对照组总有效率76.92%(30/39),治疗组临床疗效优于对照组(P<0.05)。2组治疗后血清BMP9、VEGF水平均升高(P<0.05),且治疗组高于对照组(P<0.05)。2组治疗后疼痛VAS、TLICS评分均降低(P<0.05),且治疗组低于对照组(P<0.05)。治疗后2组ODI评分均降低(P<0.05),且治疗组低于对照组(P<0.05);治疗后2组JOA腰痛评分均升高(P<0.05),且治疗组高于对照组(P<0.05)。治疗后2组椎体前缘丢失高度、伤椎Cobb角均降低(P<0.05),伤椎骨密度均升高(P<0.05),且治疗组改善均优于对照组(P<0.05)。治疗组并发症总发生率4.88%(2/41),对照组并发症总发生率20.51%(8/39),治疗组并发症总发生率低于对照组(P<0.05)。结论滋肾续骨汤治疗老年椎体压缩性骨折术后患者疗效显著,可有效改善临床症状及血清BMP9、VEGF水平。     

Hot Deformation Behavior and Microstructural Evolution Based on the Processing Map of Dual-Phase Mg-Li Based Alloy

The deformation behavior of the as-extruded Mg-Li-Al-Zn-Si alloy was studied by conducting a hot compression test, with a temperature range of 180–330 °C and a strain rate range of 0.01–10 s⁻¹. The constitutive relationship of flow stress, temperature, and strain rate was expressed by the Zener–Hollomon parameter and included the Arrhenius term. By considering the effect of strain on the material constants, the flow stress at 240–330 °C could be precisely predicted with the constitutive equation (incorporating the influence of strain). A processing map was established at the strain of 0.7. The unsafe domains that are characterized by uneven microstructures were detected at low temperatures (<230 °C) or high temperatures (>280 °C), with high strain rates (>1 s⁻¹). The optimum hot deformation region was obtained at a medium temperature (270–300 °C), with a peak power dissipation efficiency of 0.44. The microstructural evolution in different domains is investigated. The unstable domains are characterized by a non-uniform flow behavior and uneven microstructure. The observation showed that the dynamic recrystallization (DRX) process could easily occur at the safe domain with high power dissipation efficiency. For the α-phase, some features of continuous dynamic recrystallization can be found. The triple points serve as prominent nucleation sites for the β-phase DRX grains and the growth in the grains was carried out by subgrain boundary migration. The microstructure exhibits characteristics of discontinuous dynamic recrystallization.     

Foot arch height,toe flexor strength,and dynamic balance ability in collegiate female dancers and non-dancers

[Purpose] To characterize the foot arch height, toe flexor strength, and dynamic balance ability of collegiate female dancers and age-matched non-dancers. [Participants and Methods] This study included 20 healthy college-aged female dancers (21.6 ± 0.8 years) and 20 age-matched females (19.7 ± 1.0 years) with no previous experience in sports as non-dancers. Foot arch height was determined by measuring the height of the navicular tuberosity in the standing position using a ruler. Toe flexor strength was measured while seated on a chair using a toe grip dynamometer. Dynamic balance ability was evaluated based on the reach distance measured using a professional Y-balance test kit. [Results] The collegiate dancers had higher foot arches, greater toe flexor strength, and longer Y-balance test reach distance than the non-dancers. [Conclusion] The foot arch height, toe flexor strength, and dynamic balance ability of collegiate female dancers were adapted through years of training and were superior to those of non-dancers.     

锁骨钩钢板固定治疗TossyⅢ型肩锁关节脱位的临床研究

目的:评价应用锁骨钩板治疗完全性肩锁关节脱位的临床疗效.方法:31例均为TossyⅢ型肩锁关节完全性脱位,应用锁骨钩板固定治疗.所有病例均直接修复断裂的肩锁韧带.结果:全部病例获得随访,随访6～18月,平均为12月.结果按karlsson标准进行评价,优良22例,满意9例,差0例.患者无感染,无金属内植物折断及松动,肩锁关节无再脱位.结论:锁骨钩钢板固定可靠,可以早期进行功能锻炼,是治疗完全性肩锁关节脱位的一种可靠的方法.     

犬腰骶神经根慢性压迫模型的建立及分子生物学分析

目的:制作犬腰骶神经根压迫的动物模型,进一步探讨神经根压迫造成的根性疼痛及麻木的治疗方法.方法:18只成年杂种犬,均为雄性,随机分成3组:7d组、14d组和28d组,每组6只.应用长5mm、直径3～4mm的硅胶管植入右侧L6、L7及S1神经根下面,造成压迫模型,左侧作为自身对照侧.结果:通过对压迫神经根及神经根节大体观、组织病理学和免疫组织化学的光学显微镜的动态观察,可见神经根压迫后其有髓神经纤维数目减少和超微结构的改变,如神经膜细胞胞质肿胀和细胞水肿、华勒变性、神经轴突脱髓鞘变等.结论:神经根超微结构的改变是神经根失功能的病理形态学基础,此模型更接近于腰椎间盘突出和椎间管狭窄对神经根的压迫,为临床神经根性疼痛及麻木治疗的研究建立了可供参考的动物模型.