CD27 Promotes Survival of Activated T Cells and Complements CD28 in Generation and Establishment of the Effector T Cell Pool

CD27, like CD28, acts in concert with the T cell receptor to support T cell expansion. Using CD27−/− mice, we have shown earlier that CD27 determines the magnitude of primary and memory T cell responses to influenza virus. Here, we have examined the relative contributions of CD27 and CD28 to generation of the virus-specific effector T cell pool and its establishment at the site of infection (the lung), using CD27−/−, CD28−/−, and CD27/CD28−/− mice. We find that primary and memory CD8+ T cell responses to influenza virus are dependent on the collective contribution of both receptors. In the primary response, CD27 and CD28 impact to a similar extent on expansion of virus-specific T cells in draining lymph nodes. CD27 is the principle determinant for accumulation of virus-specific T cells in the lung because it can sustain this response in CD28−/− mice. Unlike CD28, CD27 does not affect cell cycle activity, but promotes survival of activated T cells throughout successive rounds of division at the site of priming and may do so at the site of infection as well. CD27 was found to rescue CD28−/− T cells from death at the onset of division, explaining its capacity to support a T cell response in absence of CD28

Innovations of Enterprise Organization in the Network Economy Age

Based on the network economy the innovation of enterprise organization is a kind of innovation activity which regards IT application as foundation, integrates resources and shares information as the principle, authorizes work team and emphasizes the humanized management as the guide, quickly responds to changing market demand as the goal. This paper, by anglicizing the drawbacks of traditional hierarchies organization mode and development trend of enterprise organization, discusses the learning organization, business process reengineering and virtual organizations which make contributions to the innovation of enterprise organization based on the network economy, and analyses the obstacles of achieving the organization innovation. Key words: Enterprise organization; Network economy; Organization innovatio

Research on Enterprises Reputation Evaluation Based on B2B Transaction Platform

Based on traders’ goods, service,the way of transaction and transaction time, the paper establishes the B2B traders’ reputation evaluation index system, and applies the Analytic Hierarchy Process to give weight. Using the reputation evaluation model, the paper takes into account evaluators’ own reputation, transaction amount, transaction time and other factors, dynamically adjusting reputation value and generating the reputation value of traders which is as the basis for the traders to choose the trading partners, and to promote the development of B2B e-commerce.Key words: B2B; Traders; Enterprises reputation; Evaluatio

How environmental awareness affects the spatial convergence of urban economic resilience: evidence from China

This study utilizes a panel dataset covering 262 Chinese cities from 2012 to 2019 and employs spatial econometric convergence test models to investigate the impact of public environmental awareness on spatial convergence of urban economic resilience. Empirical results reveal a significant spatial convergence pattern in urban economic resilience, but environmental awareness hampers this convergence. Through a mediation analysis, we find that the role of environmental awareness in the spatial convergence of urban economic resilience is moderated by two critical factors: foreign investment and scientific expenditure. The development of foreign investment and an increase in the scale of scientific expenditure weaken the inhibitory effect of environmental awareness on the spatial convergence of urban economic resilience

Static stiffness modeling and sensitivity analysis for geared system used for rotary feeding

The positioning accuracy of rotary feed system under load greatly depends on the static stiffness of mechanical transmission system. This paper proposes a unified static stiffness model of rotary feed system with geared transmission system. Taking the torsional stiffness of transmission shaft and mesh stiffness of gear pairs into account, the motion equations of the whole transmission system are presented. Based on the static equilibrium, a unified expression for the relationship between torsional angles of two adjacent elements is derived. Then a unified static stiffness model is presented. Furthermore, analytical expressions for sensitivity analysis of the static stiffness on the individual element’s stiffness and design parameters are derived. The presented model is verified by a traditional model, and a good agreement is obtained. The influence of phase angle of meshing gear pairs on the resultant static stiffness is investigated. An example transmission system is employed to perform the sensitivity analysis and the results are analyzed. The proposed model provides an essential tool for the design of rotary feed system satisfying requirement of static stiffness

Research on Post-Evaluation of Oilfield Ground Engineering Project

Based on the research results of the scholars from domestic and overseas, we construct a evaluation index system for post- evaluation of oilfield ground engineering project focusing on the characteristics of the ground engineer project and combining the characteristics of the development of oilfield. The system includes 3 primary indicators, such as pre-project, 8 secondary indicators and 35 tertiary indicators. Multistage fuzzy evaluation with the combination of quantitative analysis qualitative analysis and degree of success method are used for Post-evaluation of oilfield ground engineering project which may lead to the reference of the decision-making of investment and management for oilfield ground engineering project.Key words: Oilfield ground engineering; Postevaluation; Evaluation index; Multistage fuzzy evaluatio