芒果苷对心肌缺血再灌注损伤TNF-a、MPO的影响

目的观察芒果苷对大鼠心肌缺血再灌注损伤（MI／R）TNF-α、MPO的影响。方法50只SD大鼠随机分为5组即假手术组、缺血再灌注模型组、芒果苷10mg/kg、20mg／kg、40mg／kg剂量组、假手术组给予等容量的生理盐水腹腔注射,完成模型全部操作只穿线不结扎。芒果苷10、20、40mg/kg剂量组分别给予相应剂量芒果苷腹腔注射21天,末次给药后一小时用于实验。采用左冠状动脉前降支结扎40min,再灌120min建立在体大鼠MIR模型。放免法检测心肌组织肿瘤坏死因子（TNF-α）含量;检测心肌组织髓过氧化酶（MPO）观察中性粒细胞（PMN）浸润、苏木素-伊红（HE）染色观察心肌组织病理改受,透射电镜观察心肌超微结构的改变。结果与模型组比较,芒果苷各剂量TNF-α和MPO含量显著降低（P〈0.01或P〈0．05）。结论芒果苷对MI／R有保护作用、芒果苷可减轻心肌细织中性粒细胞浸润,抑制炎症因子释放。     

6kV动力变微机综合保护系统技术改造与应用

与原动力变的微机综合保护系统相比,经过技术改造后的6kV动力变的微机综合保护系统具有运行可靠性强、安全性高、监视范围广、测量精准度高等特征,为6kV动力变电力系统中进线、馈出线、电容器、变压器及变电装置等高压电气设备的稳定运行奠定了坚实的技术基础。基于此,文章就6kV动力变的微机综合保护系统的改造与实际应用工作进行细致研讨,旨在增强6kV动力变的微机综合保护系统内部功能,确保6kV动力变的微机综合保护系统更好满足各领域生产建设经营用电需求,以期为相关工作提供理论性帮助。     

新型纸箱防潮上光油

由武汉现代工业技术研究院研制成功的新型纸箱防潮上光油是由石蜡、氧化聚乙烯等高分子材料经化学反应精加工而成,产品具有不含有机溶剂、无毒、无刺激性气味、无腐蚀性、不燃、不爆的特性。使用该产品时,不用骨胶和淀粉打底,一次涂刷而成。涂刷后7分钟即可干燥成膜,其膜层透明度高、光泽度好,涂膜光滑不粘连,对任何纸箱印刷油墨无影响。一般的瓦楞纸箱经过涂饰本品后,可使纸箱的表面耐磨性增强、抗划痕、强度高,且有较强的抗水性、良好的防潮性,其上光、防潮性能优于任何一种传统的上光油,可对纸箱起到美化及长期保护的作用。随着市场经济…     

高糖对大鼠骨髓间充质干细胞增殖及凋亡的影响

目的 分离培养和鉴定大鼠骨髓间充质干细胞(BMSCs),探讨高浓度葡萄糖对BMSCs增殖及凋亡的影响.方法 贴壁培养法分离纯化Wister大鼠BMSC,体外培养和连续传代.将传至第三代的BMSCs用低糖-DMEM培养液(含葡萄糖5.6 mmol/L)制成细胞悬液,计数并接种于培养瓶中,待细胞贴壁后,分组加入含不同浓度葡萄糖(5.6mmol/L、11 mmol/L、25 mmol/L、40 mmol/L)的DMEM培养液,短期组培养3～4天,长期组培养4周.分别收集细胞,噻唑蓝(MTT)法检测细胞增殖,Annexin-V/PI法检测其凋亡.结果 在实验研究中,与高糖对内皮祖细胞(endothelial p rogenitor cells,EPCs)等的影响不同,一定浓度的高糖并不显著抑制BMSCs的增殖,并不促进BMSCs的凋亡率显著增加.25 mmol/L的高糖有助于BMSCs成骨分化.结论 短期和长期(4周)培养,BMSCs具有显著的高糖耐受性.与低糖条件相比,高糖提高了细胞的成骨分化能力.     

港西一区一断块提高采收率技术对策研究

港西一区一断块构造位于黄骅凹陷中部,北大港二级潜山构造带西段,是港西古凸起基底上发育起来的上第三系油气藏。油层非均质程度比较高,孔隙度平均为31%,渗透率平均为750.5×10-3u m2,平面上岩性变化较大,呈透镜体状分布,非均质性较强。目前已经进入高含水后期开发阶段,区块的综合含水高达90%以上,主力砂体水淹严重。针对这一问题,2014年对港西开发区一区一断块进行剩余油分布及开发技术对策研究,开展有利砂体潜力分析及调整,确定潜力目标区,结合井网重组调整,达到提高采收率的目的。     

LC-MS/MS法测定大鼠血浆中的叶黄素含量

目的:建立了测定大鼠血浆中叶黄素含量的LC-MS/MS法.方法:血浆样品经乙醇沉淀蛋白,叔丁基甲醚萃取,真空抽干及流动相溶解等预处理过程后,进行LC-MS/MS分析.以甲醇-0.1％甲酸水溶液(87:13,V:V)为流动相,Agilent Eclipse Plus C18柱(2.1 mm×50 mm,1.8 mm)进行分离.采用大气压化学电离源(APCI)、多反应监控(MRM)方式进行正离子检测,内标法定量(内标为麦角甾醇).结果:测定血浆中叶黄素的线性范围为5～200 ng/mL,线性相关系数r=0.997;定量下限为5 ng/mL;低(10 ng/mL)、中(50 ng/mL)、高(160 ng/mL)三个浓度的方法回收率分别为69.7％、94.9％和98.1％;提取回收率分别为75.3％、70.9％和73.4％.结论:本方法分析测试时间短、灵敏度高,适用于血浆样品中叶黄素的测定.     

On the duality of political and economic stakeholder influence on firm innovation performance: Theory and evidence from Chinese firms

Research Summary

In this study, we propose and test a multi‐stakeholder perspective to address variation in innovation performance across firms. Specifically, we analyze how a focal firm's innovation performance is shaped by its political stakeholders (local and central governments) and economic stakeholders (suppliers, buyers, and competitors). Using a data set consisting of over 26,400 Chinese firms, we first find support for our predictions that a focal firm's innovation performance will be enhanced by both its government connections and the innovativeness of its economic stakeholders. We then analyze whether the interdependent effect of these political and economic stakeholders is more likely to be synergistic versus antagonistic, and find evidence consistent with the antagonistic view.

Managerial Summary

We show how a firm's innovativeness is influenced strongly by its relationships to external stakeholders. Specifically, we examine the potentially dual‐edged role of political stakeholders (local and central governments) and economic stakeholders (suppliers, buyers, and competitors). Using extensive data on Chinese firms, we find: (a) that the higher the level of government connections, the greater a firm's innovativeness; (b) that firms located in proximity with more innovative economic stakeholders also tend to have higher innovation performance. We also look beyond these independent positive effects to examine the joint effect of these two forms of stakeholder influence, and here we see that more influence is not always better. Specifically, we find that the innovation benefit that typically accrues to firms in proximity to more innovative economic stakeholders is weakened when those firms also have higher‐level government connections.     

Synergies among Producer Firms,Lead Users,and User Communities: The Case of the LEGO Producer–User Ecosystem

While many firms today proactively involve users in their new product development efforts using a wide variety of methods such as the lead user method, firm‐hosted user communities, or mass customization toolkits, some pioneering firms are experimenting with the creation of sustainable producer–user ecosystems designed for the continuous exploration and exploitation of business opportunities. In this paper, the functioning of such ecosystems is studied with particular emphasis on the synergies they can yield. Based on an explorative and longitudinal multiple case study design, the producer–user ecosystem of the firm LEGO is analyzed, and three main actors in the ecosystem are identified: entrepreneurial lead users who aim to start their own businesses, a vibrant user community, and the LEGO company as the focal producer firm and facilitator for multiple user‐to‐user and user‐to‐producer interactions. Our study reveals three kinds of synergies: (1) reduced risk for entrepreneurial lead users and the focal producer firm, (2) the extension of the design space of the focal producer firm's products, and (3) the creation of buzz within the user community. Finally, the theoretical and managerial implications of our findings for innovation researchers and practitioners are discussed.     

Multipoint contact without forbearance? How coverage synergies shape equity analysts' forecasting performance

Research Summary: Scholars regularly use multipoint contact (MPC) to explain how encountering rivals in different domains shapes performance. While most explanations rely on mutual forbearance theory, I propose that competitive deterrence does not adequately explain how MPC shapes performance in knowledge intensive work and argue instead that cross-domain synergies may play a central role. I examine how security analysts' MPC with publicly traded firms captures synergies in their coverage portfolio, which improves forecasting accuracy and information leadership. The advantages of greater MPC for a focal analyst are counterbalanced by rivals' observational learning, which reduces the focal analyst's forecasting differentiation. A natural experiment helps corroborate my argument: rival analysts' forecasting accuracy dropped for firms in which high MPC analysts perished in the terrorist attack on September 11, 2001. Managerial Summary: Competition in the knowledge economy often unfolds across multiple domains including product markets, geographic locations, and customer segments. In these settings, an actor's level of multipoint contact (MPC) in a domain captures the knowledge and other synergies available to the focal actor, which can improve performance in the domain. In the equity research setting, an analyst's MPC on a focal firm captures the likelihood that the analyst also covers that firm's suppliers, customers and important competitors. Using data on analysts' forecasting performance between 2001 and 2013, I find that greater levels of MPC on a focal firm predicts greater forecasting accuracy and information leadership but also lowers forecasting differentiation by attracting rivals who observe and benefit from the focal analyst's knowledge.     

非对称信息下再制造产品质量控制决策研究

本文研究了风险中性的单再制造商与单销售商构建的二级闭环供应链模型,基于博弈论和委托代理理论。在不同回收水平下,再制造商都存在单边道德风险,销售商根据影响再制造商质量预防水平的因素来引导再制造商的决策,并制定激励契约来降低再制造商的道德风险,以达到闭环供应链协调的目的。研究表明：回收水平和质量检测水平均影响再制造商的质量预防水平,回收水平同质量预防水平呈正相关,质量检测水平同质量预防水平呈负相关;在不同回收水平下,通过销售商质量检测控制后,闭环供应链收益增加,同时求得最优控制水平和最优契约金额。在最后,通过算例分析验证了契约的有效性。     

The influence of desire for control on monitoring decisions and performance outcomes in strategic alliances

Strategic alliances are fraught with risks, such as the uncontrolled disclosure of core knowledge via opportunistic learning. The usefulness of monitoring in policing opportunism notwithstanding, a contrasting view is that monitoring mechanisms can themselves manifest the dark side of strategic alliances. The present study argues that a novel dark personality trait—the focal firm's desire for control—may influence key decisions pertaining to how to monitor strategic alliances, which in turn can negatively impact performance outcomes. Our conceptual model was developed and tested, based on a survey of 404 strategic alliances. The results demonstrate that a focal firm's desire for control is positively associated with process monitoring as well as output monitoring. The firm's use of process monitoring to oversee the counterpart drives its performance outcomes only if there is a low level of information exchange between the alliance partners; as such, information exchange norms substitute for process monitoring. By contrast, the focal firm's use of outcome monitoring is negatively linked to performance unless complemented by a high level of information exchange. Key implications for alliance management and future research are derived from the findings.     

Managing innovation networks: Exploratory evidence from ICT, biotechnology and nanotechnology networks

This study examines the management of innovation networks which has enjoyed increased recognition in the marketing literature due to its growing prominence and relevance. By testing a causal model relating network factors to outcomes, the study contributes to theory development on managing innovation at the net level of analysis. Consequently, it contributes to the respective marketing literatures on new product development, open innovation, industrial marketing and its emerging network management sub-stream. It also offers a methodological contribution as respondents include key players from businesses, government agencies, research organizations and universities rather than from only one focal organization as studies in extant literature have predominantly done. Findings are based on 219 responses from Australian high technology networks, namely, information and communications technology and biotechnology/nanotechnology. The study offers valuable implications for marketing managers involved in new product development and innovation concerning strategies for managing their inter-organizational innovation initiatives effectively.     

Smoothing, Nonsynchronous Appraisal and Cross-Sectional Aggregation in Real Estate Price Indices

In this article three econometric issues related to private-equity return indices, such as real estate indices, are explored (smoothing, nonsynchronous appraisal and cross-sectional aggregation). Under certain assumptions, it is found that index returns based on appraisals follow an ARFIMA(1, d , 1) (autoregressive fractionally integrated moving average) process, where the long memory parameter ( d ) explains the level of smoothing and the AR and MA parameters represent the level of persistence in marketwide fundamentals and the nonsynchronous appraisal, respectively. The empirical results show that: (1) the level of smoothing in appraisal-based real estate indices is far less than assumed in many academic studies (2) there is weak evidence of nonsynchronous appraisal in the UK, IPD (Investment Property Databank) index and (3) marketwide fundamentals are highly persistent for the IPD index returns. On the other hand, there is no evidence of nonsynchronous appraisal or a persistent common factor in the U.S. NCREIF (National Council of Real Estate Investment Fiduciaries) index.     

盐酸法舒地尔防治外伤性蛛网膜下腔出血后脑血管痉挛初步研究

目的验证盐酸法舒地尔治疗外伤性蛛网膜下腔出血（tSAH）后脑血管痉挛的有效和安全性。方法以尼莫地平为对照,采用开放随机对照试验,探讨盐酸法舒地尔的疗效.并进行临床安全性评估。选取经CT证实tSAH的中—重型闭合性颅脑损伤患者40例,随机分为法舒地尔及尼莫地平治疗组,同时选取未行抗血管痉挛治疗的20例tSAH患者作为空白对照。应用经颅多普勒（TCD）观察伤后48h,72h,5d,7d和12d大脑中动脉,颈内动脉血流动力学变化及1个月后的Glasgow预后评分;并对患者的重要脏器功能及迟发出血发生率进行比较。结果盐酸法舒地尔与尼莫地平都可明显降低tSAH后脑血管的痉挛程度和改善患者预后,两药物之间疗效并无统计学差异。对照组有2例外伤后继发梗塞出现,治疗组未出现类似病例。临床安全性研究发现盐酸法舒地尔对肝、肾功能均无明显影响,且不会增加迟发性颅内出血的比例。结论对于tSAH后迟发脑血管痉挛的治疗,盐酸法舒地尔是一种安全有效的药物。     

Technological collaboration in the korean electronic parts industry: patterns and key success factors

This study empirically examines different patterns of collaborative technological development projects and the key success factors (KSFs), using data from 82 projects in the Korean electronic parts industry. The patterns of technological collaboration were categorized into 4 types by two contingency variables: development motive (technology–push or market–pull) and source of initiation (focal firm– or partner–initiated). The bivariate relationships revealed that project characteristics (technological complexity, demand certainty, and financial support of the government), partner characteristics (the level of trust with partners), and collaborative management practices (commitment of the focal firm, and information sharing in the collaboration process) appear to be different depending on the two contingency variables. Each type of collaborative R&D project also had different KSFs. While diverse characteristics like strategic importance, goal compatibility and information sharing with partners are critical for the success of technology–push projects, just only specificity of collaboration process and outcome appears important to the success of demand–pull projects. For focal firm–initiated projects, project characteristics are KSFs, whilst partner characteristics and collaboration management practice are found to be more critical for the success of partner–initiated projects. The findings suggest that the different contingencies such as development motive and source of initiation bring about different patterns of collaborative technology development projects, which in turn lead to a different set of KSFs, since different information, roles of partners and the focal firms, and collaboration management practices are needed to successfully implement the different types of projects. Based on empirical results, this study discusses managerial, policy, and theoretical implications for the collaborative R&D activities taking place in the Korean electronic parts industry.