脉冲电刺激承筋穴、地机穴对下肢深静脉血流动力学指标的影响

目的：观察脉冲电刺激承筋穴、地机穴对下肢深静脉血流动力学指标的影响。方法：应用超声彩色多普勒测量电刺激承筋穴、地机穴前左侧股总静脉血流速度,然后用中频脉冲电刺激承筋穴、地机穴,然后再次测量左侧股总静脉血流速度,观察其刺激前后血流速度的变化。结果：30例测试者在电刺激承筋穴、地机穴后左侧股总静脉血流速度都有显著提高。其中提高5-10cm·s-1者15例,11-15 cm·s-1者13例,16 cm·s-1以上者2例。结论：脉冲电刺激承筋穴、地机穴引起小腿肌肉群有节律的收缩,提高下肢回心血流量,改善了下肢组织的血液循环。可作为预防下肢静脉血栓形成的有效方法。

一种小粒径复合筛片的设计与应用

通过分析2YK2160型振动筛3.2mm×3.2mm小粒径筛网损坏的原因,结合生产数据将锰钢丝筛网设计成“托网+基网”的组合结构,在紧固部位浇注聚氨酯,聚合形成锰钢聚氨酯复合筛网。在此基础上进一步优化筛网固定方式,实施标准化维保,彻底解决3.2mm×3.2mm小粒径筛网寿命短、易损坏、筛分效率低的难题,提高设备运转率,降低职工劳动量,节约材备费消耗。

电针对家兔Oddi括约肌运动及其相关脑肠肽的影响

背景:"经脉-脏腑相关"是针灸经络学说中主要的研究内容之一,课题以一个脏腑为基础研究其与多条经脉之间的关系,探讨经脉与脏腑之间是否存在相对特异性。目的:通过电针足三阳经穴对家兔Oddi括约肌肌电发放及其相关脑肠肽胆囊收缩素浓度的影响,探讨针刺对Oddi括约肌的调整作用。设计、时间及地点:随机对照动物实验,于2005-01/2007-12在湖南中医药大学针灸推拿学重点实验室完成。材料:新西兰大耳白兔60只,体质量2.0～2.5kg,雌雄不拘,随机分为空白组、阿托品组、足三里组、阳陵泉组、四白组、承筋组,每组10只。方法:各组兔用生理记录仪记录Oddi括约肌肌电活动1h后,除空白组滴注生理盐水外,其余各组均静滴阿托品,静滴的同时足三里、阳陵泉、四白、承筋组分别电针相应腧穴20min。主要观察指标:记录处理前、后Oddi括约肌肌电各1h,放射免疫法检测血浆及Oddi括约肌组织内胆囊收缩素的浓度。结果:与阿托品组比较:空白组、四白、足三里、阳陵泉组慢波高活动相及快波平均振幅升高(除足三里组快波外,均为P<0.01或P<0.05);四白、足三里、阳陵泉组均能使Oddi括约肌组织及血浆中胆囊收缩素的浓度升高(除足三里组Oddi括约肌组织胆囊收缩素浓度外,均为P<0.01或P<0.05),产生上调的效应依次为:四白组>阳陵泉组>足三里组。结论:经(穴)对所辖脏腑存在着或直接或间接的、特异性的调控作用,胆囊收缩素是针刺对胆道系统运动起调节作用的重要脑肠肽之一。

择“筋”穴疗筋病探微

在十二经脉及经外奇穴中,带“筋”字的腧穴有5个,分别是承筋穴、辄筋穴、筋缩穴、正筋穴、筋关穴,加上筋会穴(阳陵泉穴),均为治疗经筋病的要穴。《千金翼方·杂法》云:“凡诸孔穴,名不徒设,皆有深意”,试通过探析上述“筋”穴,并总结归纳其临床应用,进一步加深对“筋”穴的理解,为针灸临证治疗经筋病提供新的思路。

疏解筋肉之乏承托小腿之重--承山穴

承山穴,顾名思义,有承山托重之功。一个穴位如何能够拥有承受大山的力量呢?这不禁让人想起楚霸王项羽的“力拔山兮气盖世”,而穴位中的“楚霸王”就是承山穴。腨下分肉寻承山,承,承受、承托也;山,为土石堆叠形成的大堆也。承山穴的命名有一种说法:穴位之上有一承筋穴,承筋穴所在之处的肌肉凸起来形似山峰,而与承筋穴相接的承山穴正如同处于凹陷之中,犹如山谷一样,向上托起上面的山峰。

平衡电痉挛治疗腰椎间盘突出症后遗症52例

目的:观察运用平衡电痉挛疗法与传统针刺治疗腰椎间盘突出症后遗症的临床疗效比较。方法:以阴阳两经相配取穴,根据症候表现,每经各取两穴,相配合使用,毫针刺入肌层后,接通低频脉冲电疗仪,下肢内外两侧各放置一组电极,使下肢肌肉产生有节律性的收缩,以达到阴阳、表里、上下、内外的平衡,运行、调和血气。结果:平衡电痉挛疗法组与传统针刺组具有显著差异,P<0.05。结论:平衡电痉挛治疗腰椎间盘突出症后遗症有调阴阳,行气血,强筋固本,健脾益气的功效。

针灸治疗不安腿综合征76例

针灸治疗不安腿综合征７６例田正章（天津大港油田井下职工医院针灸科，３００２８３）不安腿综合征又称艾克包姆氏（Ｅｋｂｏｍ）综合征，好发于４０岁以上的中老年人，该病多在夜间发作，发作时下肢或酸、或胀、或蚁行感、或烧灼感，揉按捶打后可稍有缓解。重者影响睡眠...

Finite element failure analysis of continuous prestressed concrete box girders

In order to analyze the load carrying capacity of prestressed concrete box girders, failure behaviors of in-situ deteriorated continuous prestressed concrete box girders under loading are experimentally observed and a finite failure analysis method for predicting behaviors of box girders is developed. A degenerated solid shell element is used to simulate box girders and material nonlinearity is considered. Since pre-stressed concrete box girders usually have a large number of curve prestressed tendons, a type of combined element is presented to simulate the prestressed tendons of box girders, and then the number of elements can be significantly reduced. The analytical results are compared with full-scale failure test results. The comparison shows that the presented method can be effectively applied to the failure analysis of in-situ continuous prestressed concrete box girders, and it also shows that the studied old bridge still has enough load carrying capacity.

Mechanical performance of the mixed post-installed connection in low-strength concrete

Due to inadequate bearing capacity of the chemically-planted steel bar in low-strength concrete, a new mixed post-installed connection is proposed using small diameter anchoring steel bars and grouting materials together to anchor the main steel bar. To investigate the feasibility of the proposed post-installed connections, a series of pull-out tests with different anchors were conducted for comparison,including fully adhesive anchors, partially adhesive anchors,grouting material anchoring connection and the new mixed post-installed connection. The experimental results of the single steel bar pull-out test show that the mixed post-installed connection can effectively enhance the bearing capacity of post-installed steel bars in low-strength concrete. The bearing capacity is increased by nearly two times with no cone-type concrete failure compared with the fully adhesive anchor. The results show that adopting the new mixed post-installed connection can ensure that joint performance meets the requirements if the space dimension is available.

镁纤复合板门

镁纤复合板门我国目前使用的门都是采用木材和三夹板材料制成，木制门存在很多缺陷，如：不能耐火和防潮、易变形，隔音、保温程度差，特别是我国人口众多，森林资源匮乏，木材短缺日益严重／开发新的材料和新型门是急需解决的一个问题：镁纤复合板门避免了以上所述的不足...

Load-bearing characteristics of square footing on geogrid-reinforced sand subjected to repeated loading

A series of dynamic model tests that were performed on a geogrid-reinforced square footing are presented.The dynamic(sinusoidal)loading was applied using a mechanical testing and simulation(MTS)electro-hydraulic servo loading system.In all the tests,the amplitude of loading was±160 kPa;the frequency of loading was 2 Hz.To better ascertain the effect of reinforcement,an unreinforced square footing was first tested.This was followed by a series of tests,each with a single layer of reinforcement.The reinforcement was placed at depths of 0.3B,0.6B and 0.9B,where B is the width of footing.The optimal depth of reinforcement was found to be 0.6B.The effect of adopting this value versus the other two depths was quantified.The single layer of geogrid had an effective reinforcement depth of 1.7B below the footing base.The increase of the depth between the topmost geogrid layer and the bottom of the footing(within the range of 0.9B)did not change the failure mode of the foundation.

禁穴的探讨

禁穴是劳动人民同疾病做斗争的经验总结,它对针灸临床有很大意义。但由于历史条件所限,很可能有的禁穴不禁,致使许多有效穴位不能发挥其治疗作用。这是古人云禁,后人亦云禁的后果。故比,实有从新研究的必要。本文将收集针灸经典著作中的禁穴,加以分析,提出我们的见解,错误难免,愿听同道指教。

Influence of steel corrosion to flexural behavior of coral aggregate concrete beam

To study the flexural behavior and calculation model,8 coral aggregate concrete(CAC)beams with different types of steel were designed.The flexural behavior of CAC beam was tested.The failure mode,bearing capacity,the maximum crack width(ws)and average crack spacing(lm)were studied.A calculation model for the bearing capacity of CAC beam was proposed.The results indicated that with the steel strength increased,the cracking moment(Mcr)and ultimate moment(Mu)of CAC beam increased,and the development of the ws gradually slowed,which effectively inhibited the formation of cracks and improved the flexural behavior of CAC beam.For CAC structures in the ocean engineering,it is recommended to use organic new coated steel to extend its effective service life.In addition,considering the influence of steel corrosion,a calculation model for the Mcr,Mu,lm and ws of CAC beam was established.

Seismic stability of reinforced soil walls under bearing capacity failure by pseudo-dynamic method

In order to evaluate the seismic stability of reinforced soil walls against bearing capacity failure,the seismic safety factor of reinforced soil walls was determined by using pseudo-dynamic method,and calculated by considering different parameters,such as horizontal and vertical seismic acceleration coefficients,ratio of reinforcement length to wall height,back fill friction angle,foundation soil friction angle,soil reinforcement interface friction angle and surcharge.The parametric study shows that the seismic safety factor increases by 24-fold when the foundation soil friction angle varies from 25°to 45°,and increases by 2-fold when the soil reinforcement interface friction angle varies from 0 to 30°.That is to say,the bigger values the foundation soil and/or soil reinforcement interface friction angles have,the safer the reinforced soil walls become in the seismic design.The results were also compared with those obtained from pseudo-static method.It is found that there is a higher value of the safety factor by the present work.

Strength of circular concrete columns under concentric compression

An experimental study, in which six columns were loaded concentrically toinvestigate the behavior of reinforced normal strength and high strength circular columns underconcentric compression, is described. The concrete strengths of the columns were 30 MPa and 60 MPa.The primary variables considered were the concrete strength and the amount of transversereinforcement. Test results indicate that smaller hoop spacing provides higher column capacity andgreater strength enhancement in a confined concrete core of columns. For the same lateralconfinement, high strength concrete columns develop lower strength enhancement than normal strengthconcrete columns. Both the strength enhancement ratio (f'_(cc) /f'_(co)) and the column capacityratio (P_(test)/P_o) were observed to show linear increase variations with rho_s f_(yt)/f'_c incircular columns.

Progressive collapse resisting capacity of reinforced concrete load bearing wall structures

Reinforced concrete(RC) load bearing wall is widely used in high-rise and mid-rise buildings. Due to the number of walls in plan and reduction in lateral force portion, this system is not only stronger against earthquakes, but also more economical. The effect of progressive collapse caused by removal of load bearing elements, in various positions in plan and stories of the RC load bearing wall system was evaluated by nonlinear dynamic and static analyses. For this purpose, three-dimensional model of 10-story structure was selected. The analysis results indicated stability, strength and stiffness of the RC load-bearing wall system against progressive collapse. It was observed that the most critical condition for removal of load bearing walls was the instantaneous removal of the surrounding walls located at the corners of the building where the sections of the load bearing elements were changed. In this case, the maximum vertical displacement was limited to 6.3 mm and the structure failed after applying the load of 10 times the axial load bored by removed elements. Comparison between the results of the nonlinear dynamic and static analyses demonstrated that the "load factor" parameter was a reasonable criterion to evaluate the progressive collapse potential of the structure.

Load-Bearing Capacity of the Footing Resting on a Reinforced Fly Ash Slope

In several parts of the world, disposal of waste materials such as fly ash is a great problem. Application of waste materials as structural fills in foundations is one of the best solutions to disposal problems, because wastes can be used in large volumes in such applications. There may be difficulty due to poor load-bearing capacity of fly ash, especially when footing rests on the top of the fly ash fill slope. Inclusion of polymeric reinforcements as horizontal sheets within the fill may be one of the most viable solutions to improving the load-bearing capacity of reinforced fly ash slope, and it is particularly important for the situations where foundations need to be located either on the top of a slope or on slope itself. The present work is aimed at investigating the efficacy of a single layer of reinforcement in improving the lo, ad-bearing capacity when it gets incorporated within the body of a model fly ash embankment slope. An increase in load bearing capacity due to the incorporation of reinforcement in the model slope was found by conducting laboratory tests. Experimental results were compared by numerical values obtained using software GEO5 and PLAXIS.

Flexural behaviour of SFRRAC two-way composite slab with different shapes

To promote the application of green renewable materials in concrete composite slabs(CCSs)and study the flexural behavior of CCSs with different shapes,the bending performances of three CCSs with a SFRRAC base plate,one cast-in-site concrete slab of ordinary concrete and one CCS of ordinary concrete by steel bar truss(as recommended in the technical specification for precast concrete structures in Chinese)were compared through experiments.The carrying capacity,flexural behaviour and bi-directional mechanical properties of the specimens were systematically analyzed from the failure modes,load-deflection curves,load-bar strain curves,load-slip curves and crack distributions.Results show that the bending failure process of CCSs with a SFRRAC base plate is similar to that of the cast-in-site concrete slab of ordinary concrete and CCS of ordinary concrete by steel bar truss,as all of them went through the plastic phase,elastic plastic phase and failure phase with fully developed cracks and deflection.No sudden breakage or horizontal cracking of the connecting interface between the base plate and concrete topping was observed.The shape of the base plate has a major impact on the bearing capacity of the CCS with the SFRRAC base plate.When calculating the ultimate bearing capacity with the plastic yield line theory,the influence of the base plate shape on the plastic yield line position should be taken into account.

Bearing Capacity of Reinforced Foundation Beds on Soft Non-Homogeneous Ground

The reinforced two layered foundation bed considered for study consists of a layer of granular fill overlying soft non-homogeneous clay with inclusion or reinforcement （geosymhetic strips, grids or sheets） in single layer at soil-granular fill interface A method is developed to estimate the bearing capacity of a strip footing on the surface of a reinforced foundation bed over a finite layer of clay whose undrained strength increases linearly with depth incorporating the contribution of axial resistance of the reinforcement together with those of granular fill and soft ground. Parametric studies presented quantify the improvement in bearing capacity.