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Psychology. His current research interests include team processes and effectiveness in organizational settings, innovation implementation at the individual and team levels of analysis, individual and contextual determinants of individual and team creativity, and effects of social networks on knowledge and creativity in organizations.KIMIN KIM is a Ph.D. candidate in the faculty of management at McGill University, Montreal, Canada. He is currently working on his Ph.D. dissertation, which examines the social capital aspects of interorganizational networks. His research interests include the sociological investigation of intra-and interorganizational networks, network dynamics, and the strategic implications of corporate collaboration networks.ABSTRACT: From the social network perspective, this study explores the ontological structure of knowledge sharing activities engaged in by researchers in the field of information systems (IS) over the past three decades. We construct a knowledge network based on coauthorship patterns extracted from four major journals in the IS field in order to analyze the distinctive characteristics of each subfield and to assess the amount of internal and external knowledge exchange that has taken place among IS researchers. This study also tests the role of different types of social capital that influence the academic impact of researchers. Our results indicate that the proportion of coauthored IS articles in the four journals has doubled over the past 25 years, from merely 40 percent in 1978 to over 80 percent in 2002. However, a significant variation exists in terms of the shape, density, and centralization of knowledge exchange networks across the four subfields of IS-namely, behavioral science, organizational science, computer science, and economic science. For example, the behavioral science Downloaded by [Universität Osnabrueck] at 00:32 27 May 2015 266 OH, CHOI, AND KIM

Consumer interest in cosmetic industry products that produce whitening effects has increased demand for agents that decrease melanin production. Many such anti-melanogenic agents are associated with side effects, such as contact dermatitis and high toxicity, and also exhibit poor skin penetration. Considerable recent research has focused on plant-derived products as alternatives to chemotherapeutic agents that possess fewer side effects. In the current study, we investigated the anti-melanogenic effects of extracellular vesicles (EVs) extracted from leaves and stems of Dendropanax morbifera.Using spectrophotometric and biochemical approaches, we found that leaf-derived extracellular vesicles (LEVs) and stem-derived extracellular vesicles (SEVs) reduced melanin content and tyrosinase (TYR) activity in the B16BL6 mouse melanoma cell line in a concentration-dependent manner. An electron microscopy analysis further confirmed that LEVs and SEVs induce a concentration-dependent decrease in melanin content in melanoma cells. Both LEVs and SEVs exerted a greater whitening effect on m e l a n o m ac e l l st h a na r b u t i n ,u s e da sap o s i t i v ec o ntrol, with LEVs producing the greater effect. Notably, neither LEVs nor SEVs induced significant cytotoxicity. We also examined the effects of plantderived EVs on the expression of tyrosinase-relatedp r o t e i n s(T R P s)i nm e l a n o m ac e l l s .L E V si n h i b i t e d expression of melanogenesis-related genes and proteins, including microphthalmia-associated transcription factor (MITF), TYR, TRP-1 and TRP-2. In a human epidermis model, LEVs exerted a stronger inhibitory effect on melanin production than arbutin. Collectively, our data suggest that LEVs from D. morbifera may be a novel candidate natural substance for use as an anti-melanogenic agent in cosmeceutical formulations.

Background: Virtual reality (VR) technologies have been shown to be beneficial in various areas of health care; to date, there are no systematic reviews examining the effectiveness of VR technology for the treatment of spinal pain. Purpose: To investigate the effectiveness of VR technology in the management of individuals with acute, subacute, and chronic spinal pain. Methods: Six electronic databases were searched until November 2019. Randomized controlled trials (RCTs) assessing the effectiveness of VR were eligible for inclusion. Two independent reviewers extracted the data and assessed the risk of bias for each study and the overall quality of evidence. Mean differences of outcomes were pooled as appropriate using random-effects models. Results: Seven RCTs with high risk of bias met review criteria. Quality of evidence ranged from very low to low quality. In patients with chronic neck pain, VR improved global perceived effect (GPE), satisfaction, and general health at short-term follow-up, as well as general health and balance at intermediate-term follow-up compared to kinematic training. VR improved pain intensity and disability at short-term and long-term follow-up compared to conventional proprioceptive training in patients with chronic neck pain. In patients with either subacute or chronic low back pain (LBP), VR improved pain, disability, and fear of movement compared to lumbar stabilization exercises and improved pain compared to conventional physical therapy (at short-term follow-up). In patients with chronic LBP, VR improved pain compared to lumbar stabilization exercises and improved fear of movement compared to conventional physical therapy (at short-term follow-up). Conclusion: VR's potential for improvement in outcomes for spinal pain that demonstrated statistical and/or clinical significance (pain intensity, disability, fear of movement, GPE, patient satisfaction, general health status, and balance) highlights the need for more focused, higher-quality research on the efficacy and effectiveness of VR for treatment of patients with spinal pain. &

Non-axisymmetric magnetic perturbations can fundamentally change neoclassical transport in tokamaks by distorting particle orbits on deformed or broken flux surfaces. This so-called non-ambipolar transport is highly complex, and eventually a numerical simulation is required to achieve its precise description and understanding. A new df particle orbit code (POCA) has been developed for this purpose using a modified pitch-angle collision operator preserving momentum conservation. POCA was successfully benchmarked for neoclassical transport and momentum conservation in the axisymmetric configuration. Non-ambipolar particle flux is calculated in the non-axisymmetric case, and the results show a clear resonant nature of nonambipolar transport and magnetic braking. Neoclassical toroidal viscosity (NTV) torque is calculated using anisotropic pressures and magnetic field spectrum, and compared with the combined and 1= NTV theory. Calculations indicate a clear dB 2 scaling of NTV, and good agreement with the theory on NTV torque profiles and amplitudes depending on collisionality.