A protein conformation transition from random coil and/or helical conformation to beta-sheet is known to be central to the process used by silk-spinning spiders and insects to convert concentrated protein solutions to tough insoluble threads. Several factors including pH, metallic ions, shear force, and/or elongational flow can initiate this transition in both spiders and silkworms. Here, we report the use of proton induced X-ray emission (PIXE), inductively coupled plasma mass spectroscopy (ICP-MS) and atomic adsorption spectroscopy (AAS) to investigate the concentrations of six metal elements (Na, K, Mg, Ca, Cu, and Zn) at different stages in the silk secretory pathway in the Bombyx mori silkworm. We also report the use of Raman spectra to monitor the effects of these six metallic ions on the conformation transition of natural silk fibroin dope and concentrated regenerated silk fibroin solution at concentrations similar to the natural dope. The results showed that the metal element contents increased from the posterior part to the anterior part of silk gland with the exception of Ca which decreased significantly in the anterior part. We show that these changes in composition can be correlated with (i) the ability of Mg2+, Cu2+, and Zn2+ to induce the conformation transition of silk fibroin to beta-sheet, (ii) the effect of Ca2+ in forming a stable protein network (gel), and (iii) the ability of Na+ and K+ to break down the protein network.
Purpose – The purpose of this study is to identify key factors that facilitate knowledge sharing in collectivistic cultures and further help better understand knowledge management in the international context. Design/methodology/approach – Using a survey method, this study collected data from over 200 managerial employees in knowledge management-based project teams from China. Regression analysis was then conducted to analyze the impact of individual differences and environmental factors on the willingness to share knowledge among team members to identify key factors for successful knowledge retention in the constantly changing organizational environment in a collectivistic context. Findings – The results show that incentives are very important in individual’s decision to share knowledge in project teams even in a collectivistic culture like China and both intrinsically and extrinsically motivated individuals tend to share more knowledge with their team members. Individuals with high altruism are also found more likely to share knowledge with others. Moreover, a trusting environment and explicit knowledge will facilitate knowledge sharing for better retention. Research limitations/implications – More studies should be conducted in other collectivistic cultures to explore cultural barriers in knowledge management in the international context and comparative studies using samples from different cultural backgrounds are also encouraged to help extend the theories on knowledge management. Originality/value – While it is well-known that knowledge sharing is essential for organization to maintain competitive advantage, relatively few studies have examined knowledge sharing in collectivistic cultures, and even fewer have done so in China. This study adds values to the literature by identifying key factors for knowledge sharing in China, and thus helps refine the knowledge management theories and provides insights for multinationals on knowledge management in the Chinese market.
Employee engagement and commitment has been a very important issue in human resource managers' agenda. The present study adds to the literature by examining the impact of high-performance work systems (HPWS) on employee attitudes and on employee engagement in China in response to the increasing interest in the universalistic effects of HPWS in the globalized world market. With the data from 782 employees working in China's manufacturing and service sectors, this study shows that HPWS are positively related to employees' positive mood and job satisfaction, and that job satisfaction and positive mood lead to high employee engagement. Moreover, employee's positive mood and job satisfaction also mediate the relationship between HPWS and employee engagement. The result helps explore one mechanism via which HPWS affect employee behaviors and provides empirical evidence for the applicability of HPWS in an international context.Research has shown that an engaged workforce can lead to numerous benefits, such as high organizational performance, high job satisfaction (e.g. Harrison, Newman and Roth 2006;Harter, Schmidt and Hayes 2002;Whitman, Van Rooij and Viswesvaran 2010), and low turnover rates (Allen, Shore and Griffeth 2003). Highly engaged employees have a passion for their work and feel a deep connection to their company while disengaged employees put only time, not energy or attention into their work (Bal, Dorien and De Jong 2013). Engaged employees are thus more enthusiastic, working harder, and are more committed to their company (Kahn 1990). They are also more creative (Sahoo and Mishra 2012), more likely to perform better (Whitman, Van Rooij and Viswesvaran 2010), and can often help create and further maintain sustainable competitive advantage for their companies (Rich, Lepine and Crawford 2010). Given the strong need for high engagement and commitment among a changing and increasingly diversified workforce, an increasing amount of research on human resource management has focused on exploring the universalistic effects of high-performance work systems (HPWS) on employee performance (Snape and Redman 2010) and on the mechanism through which the HPWS relate to employee outcomes (Bal, Dorien and De Jong 2013; Jiang et al. 2012).High-performance work systems refer to a set of broadly defined human resource management (HRM) practices, including performance-related pay, various employee communication programs, training and team-based work (Harley 2002;Huselid 1995;Jiang et al. 2012), and when used in combination, HPWS are said to be mutually reinforcing and able to generate superior organizational performance (Harley 2002;Combs et al. 2006). While an impressive array of research has explored HPWS and organizational performance in the West, relatively little has been done to explore the effectiveness of HPWS in an international context (Ghebregiorgis and Karsten 2007), even though the universalistic effect of HPWS has been the focus for many studies in the HRM field. When multinational enterprises seek international e...
Synchrotron FTIR (S-FTIR) microspectroscopy was used to monitor both protein secondary structures (conformations) and their orientations in single cocoon silk fibers of the Chinese Tussah silk moth ( Antheraea pernyi ). In addition, to understand further the relationship between structure and properties of single silk fibers, we studied the changes of orientation and content of different secondary structures in single A. pernyi silk fibers when subjected to different strains. The results showed that the content and orientation of β-sheet was almost unchanged for strains from 0 to 0.3. However, the orientation of α-helix and random coil improved progressively with increasing strain, with a parallel decrease in α-helix content and an increase in random coil. This clearly indicates that most of the deformation upon stretching of the single fiber is due to the change of orientation in the amorphous regions coupled with a conversion of some of the α-helix to random coil. These observations provide an explanation for the supercontraction behavior of certain animal silks and are likely to facilitate understanding and optimization of postdrawing used in the conjunction with the wet-spinning of silk fibers from regenerated silk solutions. Thus, our work demonstrates the power of S-FTIR microspectroscopy for studying biopolymers.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.