延长大型预焙铝电解槽槽寿命的实践

影响电解槽寿命的因素是多方面的，某公司从自身电解槽的特点出发分析出影响其槽寿命的因素，针对这些影响因素。在300kA的电解槽上采取了相应措施来延长其槽寿命，取得了一定的效果。     

提高职工素质是增强企业活力的关键

增强企业活力是一项庞大的系统工程。它既受企业外部环境的影响，又受企业内部因素的制约。而企业内部因素较之其它诸多因素，又起着决定性的作用。人是生产力中最活跃的因素，社会主义企业的职工是企业生产力中的主导因素，提高职工素质，充分发挥其积极性、智慧和创造力是增强企业活力的重要途径。这主要表现在以下几方面：     

垃圾焚烧电厂汽轮机真空影响因素分析及措施研究

垃圾焚烧发电行随着生活垃圾总量持续的增长而快速发展起来，汽轮发电机组是垃圾焚烧发电厂的重要设备，影响其真空系统稳定运行的因素较多，强化汽轮机真空影响因素分析及措施研究对其安全、经济运行等具有现实意义。从多角度对真空影响因素进行分析并提出有效的措施，从而为垃圾焚烧发电厂发展提供借鉴。     

双因素理论在高校教师管理中的应用

双因素理论是西方激励理论中的一个重要理论，本文通过对双因素理论的主要内容即保健因素和激励因素的研究分析，探索其在教师管理中的应用，在保健因素方面应关注教师满意度．营造和谐的学校环境；在激励因素方面，应从完善分配制度改革，推行教师职务聘任制，健全科学合理的考评制度以及建立健全教师培训机制四个方面做好教师管理工作。     

试样精度对深冲钢成形性指标n值、r值的影响

本文针对深冲钢成形性指标n、r值的影响因素展开讨论，从而得出其主要影响因素是试样加工精度，并提出提高检测精度的措施。     

NiTi形状记忆合金相变行为的影响因素

NiTi形状记忆合金是一种性能优良的智能材料，也是应用最为广泛的形状记忆合金。由于其丰富多变的相变行为而表现出优良的形状记忆效应和超弹性，但其影响因素较多，了解其相变行为的影响因素有助于更好的应用和发展NiTi基形状记忆合金。因此本文主要介绍了Ni含量、热循环和时效对NiTi合金相变行为的影响。     

发挥“两个因素”作用 提高大学生学习绩效

“双因素理论”认为，决定人们工作积极性和工作绩效的各种因素可以归纳为“保健因素”和“激励因素”两类。大学生的任务主要是学习，同从事各种专业工作一样，他们的学习绩效也受到保健因素和激励因素的不同影响。因此，必须在满足大学生对“保健因素”需求的基础上，尽量满足其对“激励因素”的需求，调动大学生的积极性，提高大学生的学习绩效。     

高铝自流浇注料的流动性及其影响因素

本文简述了高铝自流浇注料优于其他低水泥浇注料的流动特性，并通过试验结果，分析了粒级配比，原料等因素与其性能的关系，指出了各因素对浇注性能的影响是极为重要的。     

危机下的有色金属板块

金融危机爆发后，全球资本市场和商品市场全面退缩，有色金属板块全年跌幅位居A股市场第一。对有色金属板块而言，金属商品价格的下跌和大盘的下滑对其走势都有非常大的影响，究竟哪个因素是主要影响因素？还是两者都是？     

钛酸锶压敏陶瓷及其性能影响因素

为了提高SrTi03压敏陶瓷的性能，对其影响性能的因素进行了论述，指出主要影响因素是配方体系及制造工艺中的绕结工艺，并指出改善SrTi03综合性能的途径是进一步提高瓷料配方的适应能力并完善制造工艺。     

Human factor Va1 and factor Va2: properties in the procoagulant and anticoagulant pathways

Human plasma factor V is heterogeneous and yields two forms of activated factor V that bind with low (factor Va1) and high affinity (factor Va2) to phospholipids. The properties of factor Va1 and factor Va2 in the anticoagulant and procoagulant pathways were evaluated by comparing their sensitivity for inactivation by APC and their ability to act as cofactor in prothrombin activation. At low phospholipid concentrations and on membranes containing low amounts of phosphatidylserine (PS), factor Va1 was inactivated by APC at 15-fold lower rates than factor Va2, both in the absence and in the presence of protein S. At high phospholipid concentrations and on membranes with more than 15 mol % PS, factor Va1 and factor Va2 were inactivated with equal efficiency. Differences between cofactor activities of factor Va1 and factor Va2 in prothrombin activation were only observed on membranes with less than 7.5 mol % PS. Due to the different phospholipid requirements of APC-catalyzed factor Va inactivation and of expression of factor Va cofactor activity in prothrombin activation, the thrombin-forming capacity of factor V1 was 7-fold higher than that of factor V2 in a reaction system containing factor Xa, prothrombin, APC, protein S, vesicles with a phospholipid composition resembling that of activated platelets, and traces of thrombin to initiate prothrombin activation. This shows that in the process of generation, expression, and down-regulation of factor Va cofactor activity on physiological membranes, the overall procoagulant activity of factor V1 can considerably exceed that of factor V2.     

Nocturnal physiological and biochemical changes in sudden unexplained death syndrome: a preliminary report of a case control study

We studied the interaction of factor X activation peptide (XAP) with factor IXa and factor Xa and the effect of XAP on factor IXa-catalyzed activation of factor X. XAP associated with factor Xa in the presence of 5 mM Ca2+ was dissociated from factor Xa by gel chromatography using Ultrogel AcA54 in 5 mM EDTA, or in 8 M urea-0.1% SDS. An exogenous isolated XAP inhibited the factor IXa-catalyzed factor X activation both in the presence and absence of factor VIIIa. 4-Amidinophenylmethylsulfonyl (aPMS)-factor Xa independent of XAP also inhibited the factor X activation more effectively than XAP alone in the presence of factor VIIIa. However, aPMS-factor Xa independent of XAP hardly inhibited the factor X activation in the absence of factor VIIIa. The binding of 125I-labeled factor X to the aPMS-factor IXa fixed to a microwell plate was inhibited by unlabeled factor X or XAP, but not by aPMS-factor Xa with or without XAP. Factor IXa directly bound to XAP and aPMS-factor Xa with XAP, but did not bind to aPMS-factor Xa without XAP. These findings suggest that the region of XAP in factor X directly interacts with factor IXa, and factor Xa region other than XAP interacts with factor VIIIa. Desialation or deletion of N-linked carbohydrates of XAP reduced the inhibitory activity of XAP for the factor X activation by factor IXa to approximately 50% of that of the intact XAP. This suggests that the sialic acids in the carbohydrate chains of the XAP region partly contribute to the interaction with factor IXa during its activation.     

Efficacy of the Substance Abuse Subtle Screening Inventory-3 (SASSI-3) in identifying substance dependence disorders in clinical settings

We have shown that hepatocyte growth factor/scatter factor can stimulate activation and early division of adult satellite cells in culture, and that the action of hepatocyte growth factor/scatter factor is similar to the action of the unidentified satellite cell activator found in extracts of crushed muscle. We now provide new evidence that hepatocyte growth factor/scatter factor is present in uninjured adult rat skeletal muscle and that the activating factor in crushed muscle extract is hepatocyte growth factor/scatter factor. Immunoblots of crushed muscle extract demonstrate the presence of hepatocyte growth factor/scatter factor. Furthermore, crushed muscle extract stimulates the scattering of cultured MDCK cells. Immunolocalization studies with adult rat skeletal muscle show the presence of hepatocyte growth factor/scatter factor in the extracellular matrix surrounding muscle fibers; in addition, the receptor for hepatocyte growth factor/scatter factor, c-met, is localized to putative satellite cells. In muscle from mdx mice, hepatocyte growth factor/scatter factor and c-met are colocalized in activated satellite cells in regions of muscle repair. Moreover, the satellite cell-activating activity of crushed muscle extract is abolished by preincubation with anti-hepatocyte growth factor antibodies. Finally, direct injection of hepatocyte growth factor/scatter factor into uninjured tibialis anterior muscle of 12-month-old rats stimulated satellite cell activation. These experiments demonstrate that hepatocyte growth factor/scatter factor is present in muscle, can be released upon injury, and has the ability to activate quiescent satellite cells in vivo.     

Effects of daily fat or ethanol ingestion on the cholecystokinin- pancreas and the gastrin- enterochromaffin-like cell axes in rats

In this report we describe an in vitro model of blood coagulation reactions that mimics as closely as possible the in vivo condition. Our model indicates that the tissue factor-factor VIIa complex initiates coagulation by activating small amounts of both factor IX and factor X in the environment of the tissue factor bearing cell. Factor Xa and factor IXa formed in the initial reaction then play very distinct roles in the subsequent interactions of the clotting mechanism leading to a burst of thrombin generation on the platelet surface. Our results also indicate that factor XI can be activated by thrombin in the absence of factor XII and that the function of factor XI is simply to enhance conversion of factor IX to factor IXa resulting in enhanced thrombin generation on the platelet surface.     

Polyserositis in a female patient with hypothyroidism

Advances in our knowledge of the biochemistry of coagulation have facilitated the development of sensitive and specific assays that are able to detect the generation of coagulation enzymes in vivo. It has been demonstrated that the factor VII-tissue factor pathway functions under normal conditions to generate factor Xa and convert prothrombin to thrombin. Furthermore, the factor VII-tissue factor pathway is also mainly responsible for the activation of factor IX with minimal contribution from the contact phase. However the relatively high levels of factor IXa generated are unable to convert factor X to factor Xa under basal conditions. Prospective studies are required to determine whether "biochemically" hypercoagulable individuals (i.e., those with elevated levels of free factor VIIa, activation peptides of factor IX, factor X, or prothrombin) are more likely to develop arterial or venous thrombosis.     

Factor XII-induced mitogenesis is mediated via a distinct signal transduction pathway that activates a mitogen-activated protein kinase

Clotting factor XII (Hageman factor) contains epidermal growth factor (EGF)-homologous domains and is reported to be a potent mitogen for human hepatoma (HepG2) cells. In this study, we tested whether factor XII exhibits growth factor activity on several other EGF-sensitive target cells, including fetal hepatocytes, endothelial cells, alveolar type II cells, and aortic smooth muscle cells. We found that factor XII significantly enhanced [3H]thymidine incorporation in aortic smooth muscle cells (SMCs) and all other cells tested. Tyrphostin, a growth factor receptor/tyrosine kinase antagonist, inhibited both EGF- and factor XII-induced responses. However, differences in the levels of magnitude of DNA synthesis, the observed synergism between EGF and factor XII, and the differential sensitivity to tyrphostin suggest that the EGF receptor and the factor XII receptor may be nonidentical. The factor XII-induced mitogenic response was achieved at concentrations that were 1/10th the physiologic range for the circulating factor and was reduced by popcorn inhibitor, a specific factor XII protease inhibitor. Treatment of aortic SMCs with factor XII, as well as activated factor XII, resulted in a rapid and transient activation of a mitogen-activated/extracellular signal-regulated protein kinase with peak activity/tyrosine phosphorylation observed at 5 to 10 min of exposure. Taken together, these data (i) confirm that clotting factor XII functions as a mitogenic growth factor and (ii) demonstrate that factor XII activates a signal transduction pathway, which includes a mitogen-activated protein kinase.     

Mutability and propensity in causal selection.

We examined differences in causal ratings of 1 factor depending on the mutability (defined as the ease with which a factor can be imagined to be different) and causal propensity (defined as the likelihood that the event would occur in the presence of a factor) of another factor that conjoined to produce the event. In 3 studies, causal ratings of the target factor depended on the interaction of mutability and propensity of the other factor. When the other factor was high in mutability, ratings of the target decreased as the propensity of the contributing factor increased, but when the other was low in mutability, ratings of the target increased as the propensity of the contributing factor increased. Mediation analysis indicated that mutability and propensity affected causal ratings by determining the comparison against which the event was considered. Comparison judgments also mediated beliefs about which factor should have adjusted to the other. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Thrombin activates factor XI on activated platelets in the absence of factor XII

Thrombin can activate factor XI in the presence of dextran sulfate or sulfatides. However, a physiological cofactor for thrombin activation of factor XI has not been identified. We examined this question in a cell-based, tissue factor-initiated model system. In the absence of factor XII, factor XI enhanced thrombin generation in this model. The effect on thrombin generation was reproduced by 2 to 5 pmol/L factor XIa. A specific inhibitor of factor XIIa did not diminish the effect of factor XI. Thus, factor XI can be activated in a model system that does not contain factor XIIa or nonphysiological cofactors. Preincubation of factor XI with activated platelets and thrombin or factor Xa enhanced subsequent thrombin generation in the model system. Preincubation of factor XI with thrombin or factor Xa, but without platelets, did not enhance thrombin generation, suggesting that these proteases might activate factor XI on platelet surfaces. Thrombin and factor Xa were then directly tested for their ability to activate factor XI. In the presence of dextran sulfate, thrombin or factor Xa activated factor XI. Thrombin, but not factor Xa, also cleaved detectable amounts of factor XI in the presence of activated platelets. Thus, thrombin activates enough factor XI to enhance subsequent thrombin generation in a model system. Platelet surfaces might provide the site for thrombin activation of functionally significant amounts of factor XI in vivo.     

Factor VIIa's first epidermal growth factor-like domain's role in catalytic activity

Factor VIIa-tissue factor complex formation initiates the extrinsic blood coagulation pathway. We investigated factor VIIa's first epidermal growth factor-like (egf1) domain's role in the catalytic activity increase caused when factor VIIa binds tissue factor. Starting with a factor VIIa with factor IX's egf1 domain (factor VII(IXegf1)a), we made 4 proteins with egf1 residues changed to those in factor VIIa, including E51A, D64Q, FG74-75PA, and K79R. We measured each enzyme's affinity for tissue factor and determined the enzymes' kinetic constants with and without tissue factor. The Kd for factor VII(IXegf1)a binding to tissue factor was 60-200-fold higher than that of factor VIIa depending on the assay employed. Only factor VII(IXegf1)a with the K79R (K79Ra) mutation, among all the mutants, had an effect on binding with a Kd 3-8-fold lower than that of factor VII(IXegf1)a. In kinetic analyses with a small peptide substrate, in the absence of tissue factor, factor VIIa, factor VII(IXegf1)a, and K79Ra had similar kcat's and Km's. With tissue factor, due to a kcat decrease, factor VII(IXegf1)a's catalytic efficiency (kcat/Km) was 2-fold lower than factor VIIa's. K79Ra's catalytic efficiency was intermediate between those of factor VIIa and factor VII(IXegf1)a. With factor X as substrate, in the absence of tissue factor, K79Ra and factor VII(IXegf1)a had catalytic efficiencies 1.5-fold and 2-fold lower than that of factor VIIa. In contrast, with tissue factor and with factor X as substrate, due to higher Km's, factor VII(IXegf1)a and K79Ra had only 9% and 33% of factor VIIa's catalytic efficiency. Our results suggest the egf1 domain's role in tissue factor binding involves critical alignment of tissue factor with factor VIIa's catalytic domain. Proper alignment in turn promotes optimal catalytic activities.