This study investigated the relationships among leader-member exchange (LMX), perceived job security, and employee performance. Drawing on the job demandsresources model and conservation of resources theory, we expected both LMX and perceived job security would affect employee altruism and work performance in a positive manner. In addition, LMX and perceived job security were expected to interact to predict the two outcome variables. The hypotheses were tested with a sample of 184 employees in a state-owned enterprise in China. Our results showed that LMX, but not perceived job security, was positively related to employee altruism and work performance. Additionally, the effect of LMX on altruism was stronger for employees perceiving less job security. The findings indicated that LMX as a job resource becomes more impactful to altruistic performance when employees feel less secure at work.

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The extremely acidic environment of the mammalian stomach (pH 1-3) represents a stressful challenge for enteric pathogenic bacteria, including Escherichia coli, Shigella and Brucella. The hdeA (hns-dependent expression A) gene was found to be crucial for the survival of these enteric bacteria under extremely low pH conditions. We recently demonstrated that HdeA is able to exhibit chaperone-like activity exclusively within the stomach pH range by transforming from a well-folded conformation at higher pH values (above pH 3) into an unfolded conformation at extremely low pH values (below pH 3). This study was performed to characterize the action mechanisms and underlying specific structural features for HdeA to function in this unfolded conformation. In the present study, we demonstrate that the conserved 'amphiphilic' feature of HdeA, i.e. the exposure of the conserved hydrophobic region and highly charged terminal regions, is essential for exhibiting chaperone-like activity under extremely low pH conditions. Mutations that disrupt this amphiphilic feature markedly reduced the chaperone-like activity of HdeA. The results also strongly suggest that this acid-induced chaperone-like activity of HdeA is crucial for acid resistance of the enteric bacteria. Moreover, our new understanding of this amphiphilic structural feature of HdeA helps to better interpret how this unfolded (disordered) conformation could be functionally active.

Here we describe a technique for measuring changes in Ca2+ in the cytosolic domain of mature compact myelin of live axons in the central nervous system (CNS). We label the myelin sheath of optic nerve and dorsal column axons by using the Ca2+ indicator X-rhod-1 coupled with DiOC6(3) to produce bright myelin counterstaining, thereby providing unambiguous identification of the myelin sheath for analysis of two-photon excited fluorescence. We present evidence for localization of the Ca2+ reporter to the cytosolic domain of myelin, obtained by using fluorescence lifetime, spectral measurements and Mn2+ quenching. Chemical ischemia increased myelinic X-rhod-1 fluorescence (approximately 50% after 30 min) in a manner dependent on extracellular Ca2+. Inhibiting Na+-dependent glutamate transporters (with TBOA) or glycine transporters (with sarcosine and ALX-1393) reduced the ischemia-induced increase in Ca2+. We show that myelinic N-methyl-D-aspartate (NMDA) receptors are activated by the two conventional coagonists glutamate and glycine, which are released by specific transporters under conditions of cellular Na+ loading and depolarization in injured white matter. This new technique facilitates detailed studies of living myelin, a vital component of the mammalian CNS.

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Residents of rural areas live and depend on the land; hence, rural land plays a central role in the human–land relationship. The environment has the greatest direct impact on farmers’ lives and productivity. In recent years, the Chinese government carried out vigorous rural construction under a socialist framework and implemented a rural revitalization strategy. This study was performed in a rural area of Huanjiang County, Guangxi Province, China. We designed a survey to measure rural households’ perceptions of three types of rural spaces: ecological, living, and production spaces. The survey was administered to 379 farmers, and their perceptions and satisfaction with Ecological–Living–Productive spaces were evaluated with the use of structural equation modeling. Analysis of latent and observed variables indicates that: (1) Farmers’ overall satisfaction with Ecological–Living–Productive spaces was moderate. The average satisfaction score for production spaces was lowest (2.881) while that for living spaces was highest (3.468) and that for ecological spaces was in between (3.351). (2) The three most important exogenous observed variables associated with living space satisfaction were house comfort > domestic water supply > domestic sewage treatment. The three most important exogenous observed variables associated with production space satisfaction were irrigation water > cultivated land quantity > cultivated land fertility. The three most important exogenous observed variables associated with ecological space satisfaction were garbage disposal > vegetation cover > flood and waterlogging. Based on the requirements of the rural revitalization strategy and the results of our analyses of rural households’ spatial perceptions, we propose corresponding countermeasures and suggestions.

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With rapid urbanization and industrialization, ecological disorders and environmental degradation have become serious, and the promotion of the coordinated development of the social economy and ecological environment is not only a pressing problem to be solved, but also an important step towards sustainable development. The coordinated development of the social economy and eco-environment is conducive to sustainable development. Considering the Chengdu–Chongqing urban agglomeration as a case study, this paper adopts panel data and establishes an index system to evaluate the coupling coordination degree (CCD) between the social economy and ecological environment based on the concept of high-quality development. From the perspective of time and space, the changing laws and characteristics of the CCD are analyzed, and the key factors affecting it are determined using regression analysis. The results show the following: (1) the CCD between the social economy and ecological environment of the Chengdu–Chongqing urban agglomeration presents a low level overall; (2) the CCD in more developed regions is significantly higher than that in less developed regions; thus, the characteristics of spatial differences are obvious; (3) the urbanization rate, ratio of actual use of foreign capital and GDP, ratio of total export-import volume and GDP, proportion of days with good air quality, and per capita public green space area are the main factors affecting the coordinated development of the social economy and ecological environment in the Chengdu–Chongqing urban agglomeration; and (4) Chongqing has obvious endogeneity. Finally, corresponding policy recommendations are provided aimed at promoting rapid economic development in the Chengdu–Chongqing urban agglomeration while focusing on environmental protection and promoting high-quality economic development with ecological environmental protection, while putting forward decision-making suggestions for high-quality development of urban agglomerations.