不同玉米果穗位姿与含水率对穗柄断裂特性的影响

为解决现有摘穗机构功耗大、苞叶残留多的问题,该文以手工摘穗为研究模本,提炼出基于果穗位姿变化的穗柄受力断裂模型。以4种不同含水率的收获期玉米为试验材料,以果穗偏转角度为因素,进行了2组穗柄拉伸断裂随机区组试验。结果表明,随着果穗偏转角度增大,穗柄拉断力、断裂拉伸量及苞叶残留率会在一临界角度产生突变;当籽粒含水率分别为34.8%、30.2%、25.1%和20.3%时,该临界角度分别为50°～55°、50°～55°、45°～50°和45°～50°;穗柄偏转达到临界角度后,玉米穗柄拉断力分别降低了80%、86%、84%和80%,断裂拉伸量增加了72%、70%、93%和84%,苞叶去除率增加了41%、34%、32%和36%;结果表明,对茎秆施加拉力时对果穗施加横向载荷,使果穗发生大于临界角度的偏转,可实现低耗摘穗;分析发现,穗柄断裂行为突变的诱因是表层纤维的受力由拉应力变为弯曲正应力,导致裂纹的萌生和扩展机理发生变化。该研究可为新型摘穗机构的设计提供理论依据和数据支撑。     

桃仁四物汤联合鹿瓜多肽治疗创伤性骨折的临床观察

目的 观察桃仁四物汤联合鹿瓜多肽治疗创伤性骨折的临床效果。方法 纳入2015年8月至2017年8月于本院收治的86例创伤性骨折患者为对象,按照随机数字表法分为两组,每组43例。两组均接受常规基础治疗,在此前提下对照组予以鹿瓜多肽治疗,观察组实施桃仁四物汤+鹿瓜多肽联合疗法,以7 d为1个疗程,均持续治疗6个疗程。对比两组消肿止痛时间、骨痂出现时间、骨折愈合时间,观察中医证候疗效及治疗前后中医证候积分变化,并分析不良反应发生状况。结果 观察组消肿止痛时间、骨痂出现时间、骨折愈合时间均显著短于对照组（P<0.01）;观察组总有效率为90.7%,对照组为72.1%,差异有统计学意义（P<0.05）;治疗后中医证候积分（疼痛、肿胀、局部压痛、纵向叩击痛、瘀斑）均明显下降（P<0.01）,且观察组低于对照组（P<0.01）;两组治疗期间均未见明显不良反应。结论 桃仁四物汤与鹿瓜多肽联合治疗创伤性骨折疗效显著,骨折愈后时间短,安全性高。     

四君子汤合五味消毒饮加减预防老年髋部骨折术后切口感染临床研究

目的 观察四君子汤合五味消毒饮加减预防老年髋部骨折术后切口感染的临床疗效。方法 选取老年髋部骨折拟择期手术患者50例,按照随机数字表法分为治疗组26例与对照组24例。对照组术前、术后给予五水头孢唑林钠预防性治疗1次,治疗组术后预防性抗生素治疗同对照组,同时术后加服四君子汤合五味消毒饮加减。观察比较两组术后切口感染发生率、第1、3、7、14 天白细胞总数、超敏C反应蛋白、体温等指标,以评估预防术后切口感染疗效。结果 术后切口感染率分别为治疗组0%,对照组16.7%,两组感染率比较差异有统计学意义（P<0.01）;治疗组白细胞总数、C反应蛋白、体温在术后第1、3、7天均低于对照组（P<0.05）,术后第14天两组比较,差异无统计学意义（P>0.05）。结论 四君子汤合五味消毒饮加减预防老年髋部骨折术后切口感染疗效显著,值得临床推广。     

Tensile fracture properties of seven tropical grasses at different phenological stages

The intake of forage grasses by grazing ruminants is closely related to the mechanical fracture properties of grasses. The relationship between the tensile fracture properties of grasses and foraging behaviour is of particular importance in tropical reproductive swards composed of both stems and leaves. This study (i) quantified and compared the tensile fracture properties of stems and leaves of seven tropical grass species and (ii) provided insight into the underlying plant traits that explain differences in fracture properties between species. Fracture force, tensile strength, fracture energy and toughness of stems (in various phenological stages) and leaves were measured and compared among five introduced tropical grasses (Cenchrus ciliaris, Chloris gayana, Digitaria milanjiana, Megathyrsus maximus (syn. Panicum maximum), Setaria sphacelata) and two native tropical grasses (Setaria surgens and Dichanthium sericeum). Species differed significantly in fracture force and fracture energy, with stems and leaves of C. ciliaris and S. surgens requiring less force and energy to fracture and stems and leaves of M. maximus and S. sphacelata requiring more force and energy to fracture in comparison with the other species. Differences in tensile strength and toughness were less pronounced. The differences among species in fracture force and energy mainly resulted from differences in cross‐sectional area of plant parts rather than from differences in tensile strength and toughness.     

黄瓜子和生菜子提取物促进骨折愈合的试验研究

本试验主要研究黄瓜子和生菜子合用促进骨折愈合的作用及其初步机理。将蛋鸡60只,体重1.75～2.25 kg,造成右侧小腿中段横行闭合骨折模型,随机分为数目相等的高剂量组、中剂量组、低剂量组,阳性对照组和阴性对照组。试验组以不同比例的黄瓜子和生菜子提取物灌胃给药,阳性对照组以麝香接骨胶囊灌胃给药,阴性对照组以生理盐水灌胃,随后对各组进行动态观察、组织学观察、血清学观察和放射学观察。结果显示,黄瓜子和生菜子提取物中剂量组可促进全身代谢反应,提高血清碱性磷酸酶含量,加快血肿吸收机化,提高血钙、磷离子浓度,提高骨痂生成量和强度。结果表明黄瓜子和生菜子提取物可以通过提高钙、磷离子浓度,促进钙、磷向骨折断端转移而对骨折的愈合起到促进作用。     

Fracture Energy and Strain Softening ofConcrete under Seawater Environment

Both Three Points Bending (TPB) test on notched beams and Wedge Splitting Test (WST) were carried out on concrete specimens under six different conditions, under which they were totally dry, partially dry, water immersed, seawater immersed, 5% and 23.4% NaCl solution immersed, respectively. The fracture energy of each type of concrete and their strain softening curves were calculated according to the force displacement diagrams and inverse analysis method. It was indicated that with water, seawater or salt solution penetrating into concrete, the surface tension of pore liquids in concrete increased, which resulted in the decrease of the surface energy and load bearing capacity of concrete. After water immersed, the maximum bearing loads of specimens’ were reduced by 19.6% (TPB) and 14.5% (WST) compared with those of totally dry concrete. And for those of seawater immersed, 28.9% and 21.7% were reduced respectively. Furthermore, fracture energy of concrete was decreased more than 24% and fracture toughness was reduced significantly as well for concrete with high concentration salt solution, which made crack formation in concrete easier. The adverse influence of seawater on concrete materials had been investigated in detail from the aspects of surface energy, fracture energy and strain softening.     

巴楚隆起西段色力布亚断裂在含油气系统下的封堵性能

分析了巴楚隆起西段色力布亚断裂构造及演化特征,并将色力布亚断裂置于含油气系统之内进行了研究,以对该断裂的封堵性以及其对成藏的控制作用有更清楚的认识。研究结果表明,色力布亚断裂构造带处于巴楚断隆西南缘,“古高新高”均是多期油气运移的有利指向,且断裂南段下盘构造带为勘探优选目标。     

Traumatic bilateral stylohyoid bone fracture in an Appaloosa

An Appaloosa gelding presented for a traumatic puncture wound of the head ventral to the base of his left ear, bilateral epistaxis and upper respiratory compromise. The horse did not exhibit dysphagia or cranial nerve deficits. The horse suffered bilateral oblique fractures of both stylohyoid bones due to the traumatic incident, diagnosed upon endoscopy of the guttural pouches. Treatment consisted of anti‐inflammatory medication, broad‐spectrum antibiotics, guttural pouch lavage and dietary management with soft feeds. At a one‐month follow‐up examination, endoscopic evaluation revealed a union at both stylohyoid bone fracture sites. Guttural pouch mycosis was diagnosed in the left guttural pouch on the lateral wall at the entrance of the lateral compartment. The guttural pouch mycosis was treated with a nystatin and gentamicin flush, followed by a course of oral fluconazole. At the 3‐month re‐evaluation, the guttural pouch mycosis had completely responded to treatment.     

Iatrogenic fracture of the premaxilla during standing exodontia

This case report describes a 17‐year‐old horse that presented with a history of oral dysphagia secondary to buccal slab fractures and apical infection in two cheek teeth. During standing surgery to remove the diseased cheek teeth, the horse sustained a bilateral comminuted fracture of the premaxilla. An audible crack was followed by bilateral epistaxis. Subsequent radiography revealed minimal displacement at the fracture sites and the horse responded well to conservative management without the need for additional fixation techniques. One year later, the fracture appeared completely healed on repeat radiography. This is an uncommon complication of standing dental procedures necessitating the use of a speculum but is noteworthy and may be important to consider and inform owners in such aged cases.