Regularity of solutions of obstacle problems

In this paper, we improved the regularity results of obstacle problems, in which the smooth conditions of the coefficients a^ij （x） are released from C^1 （^-Ω） to L^∞ （Ω） .     

Prediction of Welding Deformation of Underframe

IntroductionWelding deformation is a common and impor-tant problem in industry.In the last decades re-searchers have made efforts to predict and controlwelding deformation.There are usually three waysto determine the welding deformation:1 experi-ential formulas.2 Thermal elastic- plastic FEMmethod.3 Inherent strain method based onFEM[1～ 3 ] .Experiential formulas are only fit for simpleshape structures.Current thermal elastic- plasticmethod usually simulated either small or simplestructur…     

Application of Computer in the Design of Process Thermal Cycle of Steel

IntroductionSteelingot.steelslabbecomest6elproductsafterheatingandrollingorforging.Steelproductsofforgingneedtobeheattfeatedinheattreatingfumace,fOrexampleannealingnormalization.Heattreatinentcandecreasestress,reducehydrogenconcentrationandimprovetheorganizationandperformanceofsteel.Everyprocessofproductionthatsteelingotschangeilltosteelproductsisaprocessofthermalcycleofsteel.Thisprocesswillconsumealargeamountofeneasmaterialandequipment.Inthepast,inmetallurgicalenterpriseofourcountrythetimeo…     

Weighted Approximation of Kantorovich-Type Operator of Butzer-Hahn

A kind of Kantorovich-type operator of Butzer-Hahn Bn^* (f; x) on the bounded and integrable function space was introduced, and the properties of Bn^* (f; x) were studied. Positive theorem, converse theorem, and the order of weighted approximation of Bn^* (f; x) were obtained.     

Preservation of the NBUCA Class of Life Distributions

Introduction As is well known, lifetime distributions can beclassified by stochastic ordering. Recently, Ahmad etal.[1]defined a new aging class, namely, NBUCA(new better than used in increasing convex average),based upon the increasing convex average order. Inthe theory of economics, this order is known as weakthird-order stochastic dominance[2]. Under the as-sumption that the elements are independent andidentically distributed (i.i.d.), the preservationproperties of this class under convo…     

Influence of Carbonation on Mechanical Properties of Concrete

As one of the most important factors that determine the lifespan of a reinforced concrete structure, carbonation not only corrodes the reinforcing steel, but also changes the mechanical properties of concrete. For better understanding the performance of carbonated concrete structure, it is necessary to study the mechanical properties of carbonated concrete. The strees-strain relationship of carbonated concrete was analyzed on the basis of experiments. The specimens were made by means of accelerated carbonation and then compressed on the testing machine. Some very important characteristics of carbonated concrete were revealed by the testing results. In addition,a useful constitutive model of carbonated concrete, which proved to be suitable for analyzing carbonated concrete members, was established in this research.     

Determination of Critical Slip Surface of Soil Slope

A new complex method is presented considering not only the improvement upon the ＂bad ＂design point, but also the diversity of the newly generated complex, which is obtained by replacing the ＂bad ＂design point with the better design point located at the line between the ＂bad ＂design point and the ceotroid of the remaining design points of the old complex. The new complex method is applied to searching for the critical slip surface of two non-homogeneous soil slopes. The comparison of the results obtained by the new complex method with that by the basic complex method shows that the new complex method is much more likely to find the true critical surface for the randomly generated initial complex.     

Picard Approximation of Fixed Points of Nonexpansive Mappings

LetXbeaBanachspaceandCbeaconvexsubsetofX .T :X→Cisanonexpansivemapping ,thatis ,Tx -Ty ≤x - y forallx ,y∈X .Now ,westudythefollowingiterativeprocessforx0 ,un∈C ,xn 1=Snxn, ( 1 )whereSn =αn0 I αn1T αn2 T2 … αnkTk γnun,andαni≥ 0 ,0 <α≤αn     

Changes in firing rate and firing pattern of midbrain dopaminergic neurons after lesioning of the dorsal raphe nucleus by 5,7-drhydroxytryptamine in adult rats

Objective To study the effect of serotonergic efferent projection of the dorsal rophe nucleus (DRN) on the activity of substantia nigro pars compacta (SNc) and ventral tegmenta area (VTA) dopaminergic neurons after lesioning of the DRN by the neurotoxin 5,7-drhydroxytryptamine (5,7-DHT) in rot. Methods The changes in the firing rote and firing pattern of SNc and VTA dopaminergic neurons were observed with extrocellular recording in control and the lesioned rats. Results The results showed that the mean firing rotes of the fast-firing dopaminergic neurons of the SNc in control and the lesioned rots were (5.34±0. 13 ) Hz (n = 23 ) and ( 7.13±0. 49 ) Hz (n=37), respectively. The mean firing rote of the fast-firing dopaminergic neurons of the SNc in the lesioned rats was significantly increased when compared to that of control rots (P<0.01), while the mean firing rote of the slow-firing dopaminergic neurons of the SNc did not change. The mean firing rotes of dopaminergic neurons of the VTA in control and the lesioned rots were (5.27±0. 38)Hz (n=35) and (3.6±0.2)Hz (n=52), respectively. Lesioning of the DRN induced a significant decrease in the mean firing rote of dopaminergic neurons of the VTA. The firing pattern of SNc and VTA dopaminergic neurons changed towards a more bursting or irrgular firing after the lesioning. Conlusion These data suggest that the serotonergic efferent projections of the DRN significantly affect the activity of SNe and VTA dopaminergic neurons.     

阻断5-HT1B受体对正常和帕金森病大鼠底丘脑核神经元活动的不同作用

目的观察体循环给予5-HT1B受体拮抗剂SB224289后,对正常大鼠和帕金森病(Parkinsons disease,PD)模型大鼠底丘脑核(subthalamic nucleus,STN)神经元电活动的影响。方法采用在体细胞外记录的方法,研究正常和PD大鼠STN神经元电活动的变化;比较阻断5-HT1B受体后两组大鼠STN神经元电活动的改变。结果①PD组大鼠STN神经元的平均放电频率[(7.87±1.37)Hz]明显高于正常组大鼠[(6.59±1.44)Hz,P<0.001]。两组大鼠STN神经元均表现为规则、不规则和暴发式放电3种形式。正常组大鼠具有规则、不规则和暴发式放电的神经元比例分别为33.33%、54.17%和12.50%;PD组分别为31.25%、35.42%和33.33%,PD组大鼠具有暴发式放电的神经元的百分比显著高于正常组(P<0.01)。②阻断5-HT1B受体后,正常大鼠STN神经元平均放电频率明显增高(P<0.01),具有暴发式放电的神经元数量显著增多(P<0.05)。而PD组大鼠阻断5-HT1B受体后STN神经元的放电频率和放电形式均无明显变化。结论 PD大鼠STN神经元呈过度兴奋状态;阻断5-HT1B受体可兴奋正常大鼠的STN神经元,而不影响PD大鼠的神经元活动。     

正常和6-羟多巴胺毁损大鼠脚桥核神经元对胆碱能M受体刺激的反应

目的 在体水平上观察选择性胆碱能M受体激动剂氧化震颤素(Oxo-M)对正常和6-羟基多巴胺(6-OHDA)毁损大鼠脚桥核(PPN)神经元自发电活动的影响.方法 采用玻璃微电极细胞外记录和PPN内注射Oxo-M,观察PPN神经元电活动的变化.结果 与正常组大鼠相比,6-OHDA毁损组大鼠PPN神经元的平均放电频率增高(P<0.01),神经元活动趋于不规则(P<0.001);PPN内注射Oxo-M对正常组和6-OHDA毁损组大鼠的PPN神经元放电频率均可产生升高、降低和无变化三种改变.然而,PPN内注射Oxo-M对正常组大鼠PPN神经元的平均放电频率无明显影响,但Oxo-M使6-OHDA毁损组大鼠PPN神经元的平均放电频率显著降低(P<0.001).结论 胆碱能M受体激动剂抑制损毁组大鼠PPN神经元的活动,其作用机制是复杂的,涉及到PPN内突触前和突触后胆碱能受体.     

大鼠下丘脑室旁核大细胞自发电活动及对去甲肾上腺素反应的增龄性变化

应用神经垂体逆向电刺激,于下丘脑室旁核内用玻璃微电极细胞外记录的方法寻找室旁核神经内分泌大细胞,并观察了３ 月龄、１２ 月龄及２６ 月龄三组大鼠室旁核大细胞的自发放电及对脑室注射去甲肾上腺素（Ｎｏｒｅｐｉｎｅｐｈｒｉｎｅ ,ＮＥ）反应的增龄性变化。结果发现,不同月龄组室旁核大细胞中呈慢不规则、快连续及位相型放电的神经元的比例相似;随增龄室旁核大细胞的自发放电频率增加;室旁核中加压素与催产素神经元对脑室注射ＮＥ的反应发生增龄性变化。这些结果提示：下丘脑室旁核大细胞电生理特性发生增龄性变化,并可能因此导致其分泌功能的变化     

化学性交感神经切断术在大鼠糖尿病痛过敏中的作用

观察了交感传出在大鼠糖尿病痛过敏中的作用。先给大鼠腹腔注射６－羟多巴胺（６－ＯＨＤＡ）损毁交感节后神经元（ＳＰＧＮｓ）末梢后，再给予链脲佐菌素（ＳＴＺ）建立６－ＯＨＤＡ糖尿病大鼠模型。在连续６周的观察中，发现这组大鼠在行为上没有反常表现，它们的伤害性爪回缩阈值（ＮＰＷＴ）和甩尾反射潜伏期（ＴＦＵ）也没有显著变化，而糖尿病组大鼠在腹腔注射ＳＴＺ后，在行为上出现反常表现，实验至第１周时，ＴＦＬ显著缩短，第２周时，ＮＰＷＴ明显降低。结果提示ＳＰＧＮｓ在大鼠糖尿病痛过敏中起重要的作用。     

THE MORPHOLOGICAL CHANGES IN MUSCLE SPINDLES AND ALTERATIONS IN CELL ACTIVITY OF THE RATS'''' RED NUCLEUS AFTER 2 WEEKS'''' SIMULATED WEIGHTLESSNESS

The extensive negative effects induced by zerogravity or microgravity where offer special environ-ment are har mful for cos monauts[1-3].The real spaceenvironment has many characteristics,including mi-crogravity,electromagnetic fields,and radiation,which may have an effect on the function and mor-phology of the CNS[4],but the changes in CNSin-duced by si mulated weightlessness on the groundcaused the corresponding adaptive changes of cere-bral circulation,which made alterations in sensoryper…     

PI_3激酶参与AT_1受体介导Ang II调节SHR脑神经元电活动的信号转导

目的　探索AT1受体介导AngII调节SHR和WKY鼠脑神经元电活动的信号转导机制。 方法　原代培养SHR和WKY新生鼠脑干和下丘脑神经元 ,用全细胞膜片钳以电流箝方式记录神经元的放电活动 ,观察AngII及各种信号分子抑制剂对脑神经元放电频率的影响。结果　AngⅡ (10 0nmol·L-1)可使WKY新生鼠脑神经元的放电频率从 (0 .4 4± 0 .0 8)Hz增加到 (1.39± 0 .16 )Hz。这种效应在SHR鼠更加显著。由AngⅡ引起的这两种鼠脑神经元放电频率的增加均可被AT1受体拮抗剂Losartan完全消除。使用PKC抑制剂calphostinC和钙调蛋白激酶II抑制剂KN 93能完全阻断AngⅡ对WKY鼠脑神经元的作用 ,但对SHR鼠脑神经元的放电频率仅阻抑约 5 0 %。磷脂酰肌醇 3(PI3 )激酶抑制剂LY2 94 0 0 2 (10 μmol·L-1)对SHR鼠脑神经元的放电频率可产生部分阻断作用 ,但对WKY鼠脑神经元无明显影响。结论　AngII增加SHR和WKY鼠脑神经元放电频率的作用均由AT1受体介导。PI3 激酶在AngⅡ调节SHR鼠脑神经元电活动的信号转导机制中发挥重要作用     

大脑皮层下轴突纤维横断模型的建立

目的　建立一种机械性大脑皮层下轴突纤维横断动物模型。方法　对 1 0例正常 2 1 0～2 4 0 g雄性SD大鼠的大脑皮层厚度和第V层神经元深度进行测定。根据测定结果决定三组不同的横切深度 (每组用SD大鼠 8只 )。在立体定位下进行脑皮层下轴突纤维横断 ,观察动物术后肢体功能恢复情况。 1 7d后取脑进行切片和染色 ,对横切深度进行测量 ,并对神经元和神经纤维状况进行观察。结果　正常 2 1 0～ 2 4 0g雄性SD大鼠大脑皮层厚度为 ( 1 85± 0 1 2 )mm ;第V层神经元深度为 ( 1 1 7± 0 0 5 )mm。对同一预定深度所获的实际深度之间最大相差 1 60 μm。三个损伤组实际深度与预定深度差值的绝对值 |d|分别为 ( 5 0 1 7± 2 6 2 0 ) μm、( 4 6 68± 32 84)μm和 ( 4 8 70± 2 9 76) μm ,最大 |d|值为 90 μm。在损伤深度分别为 2 0 0 μm、40 0 μm和 60 0 μm时 ,神经元存活率分别为 ( 4 2 5 5± 5 1 0 ) %、( 68 96± 5 2 1 ) %和 ( 74 5 2± 5 37) %。结论　该模型模拟了多种脑白质病变导致轴突损伤的共同特征 ,重复性好 ,是进行脑轴突损伤后神经修复与再生研究较理想的模型。     

大鼠蓝斑酪氨酸羟化酶免疫反应性神经元的老年性变化

本实验用免疫金银染色法结合图像定量分析,观察了幼年(3个月)、中年(12个月)和老年(20个月)Wistar雄性大鼠蓝斑内酪氨酸羟化酶(TH)免疫反应性神经元的老年性变化,结果:蓝斑内TH免疫反应性神经元数量在中年呈显著性的减少(P<0.01),至老年,进一步减少,与幼年组比较,神经元丧失70%;TH免疲反应性神经元的胞体平均截面积随年龄增长呈增大趋势,各年龄组间有显著性差异(P<0.05);TH免疫反应性神经元的灰度值随增龄而递减,老年组与幼年组相比,下降了39%。表明蓝斑内儿茶酚胺能神经元所含TH的量和活性在衰老过程中是逐渐降低的,提示儿茶酚胺能神经递质合成能力减弱。     

THE EFFECT OF ACUTE MYOCARDIUM ISCHEMIC ON HEART FUNCTION OF PREGNANCY RAT

In recent years,extensive research is underwayto investigate characteristics of coronary heart dis-ease(CHD)among women.Epidemiology has in-dicatedthat sex difference has an obvious presenceinCHD incidence and mortality.Womenprior tomenopause have a muchlower presence inincidenceof CHD[1-2].Whilethe incidence and mortality raterise significantly among post menopausal women orthose who have ovary removed,si milar to that ofsame-age men.It showed that the estrogenlevel hasa close relationshi…