231,176 research outputs found
Retail positioning through customer satisfaction: an alternative explanation to the resource-based view
Through exploring factors influencing effective retail positioning strategies in an emerging market environment, this paper challenges the role of isolation mechanism and heterogeneous idiosyncrasy argued by the resource-based view theory. By drawing on a sample of 11,577 customers from hypermarkets, electronic appliance specialty stores and department stores in major Chinese cities, we set up ten hypotheses and confirm a nine-item model for customeroriented retail positioning (perceived price, store image, product, shopping environment, customer service, payment process, after-sales service, store policies, and shopping convenience). Our results show that different retail formats achieve success through the implementation of similar positioning strategies, in which case, it is not heterogeneity but homogeneity that contributes to retailers' success greatly at the development stage of retail expansion. Our results challenge previously proved effectiveness of inimitability to success by the resource-based view, and support homogenous idiosyncrasy of retailers in the implementation of customer-oriented positioning strategies in an emerging market
Coronal Electron Confinement by Double Layers
In observations of flare-heated electrons in the solar corona, a longstanding
problem is the unexplained prolonged lifetime of the electrons compared to
their transit time across the source. This suggests confinement. Recent
particle-in-cell (PIC) simulations, which explored the transport of
pre-accelerated hot electrons through ambient cold plasma, showed that the
formation of a highly localized electrostatic potential drop, in the form of a
double layer (DL), significantly inhibited the transport of hot electrons (T.C.
Li, J.F. Drake, and M. Swisdak, 2012, ApJ, 757, 20). The effectiveness of
confinement by a DL is linked to the strength of the DL as defined by its
potential drop. In this work, we investigate the scaling of the DL strength
with the hot electron temperature by PIC simulations, and find a linear
scaling. We demonstrate that the strength is limited by the formation of
parallel shocks. Based on this, we analytically determine the maximum DL
strength, and find also a linear scaling with the hot electron temperature. The
DL strength obtained from the analytic calculation is comparable to that from
the simulations. At the maximum strength, the DL is capable of confining a
significant fraction of hot electrons in the source
Epigenetic silencing of SOCS3 expression contributes to fibrosis in Crohn’s disease
Identified risk polymorphisms affecting the Jak-STAT3 pathway in patients with Crohn’s disease could affect TGF-β1 and collagen I expression and in the pathway’s negative regulator, SOCS3. Genetic factors, however, account for only ~25% of disease. Epigenetic events also shape gene expression. Recent experiments showed that autocrine IL-6 production in mesenchymal cells, subepithelial myofibroblasts (SEMF) and muscle cells, of patients with fibrostenotic Crohn’s disease causes sustained Jak-STAT3 activity, excess TGF-β1 and Collagen I production and fibrosis. SOCS3 paradoxically decreased in these cells. We now identify epigenetic mechanisms that silence SOCS3 expression in SEMF of patients with fibrostenotic Crohn’s disease. In a previous experiment, using isolated SEMF of normal ileum and affected ileum from patients with each Crohn’s phenotype, inflammatory (Montreal B1), fibrostenotic (B2) and penetrating (B3), we confirmed decreased SOCS3 protein levels were unique to B2 patients. Expression of miR-19b increased in SEMF of affected ileum. SOCS3 transcriptional activity decreased after transfection of miR-19b mimic and increased when antagomiR-19b was expressed. Epigenetic silencing of SOCS3 in ileal SEMF of patients with fibrostenotic Crohn’s disease occurs by increased miR-19b mediated inhibition of SOCS3
Optimization of commercial net spacers in spiral wound membrane modules
CFD simulations have been used to determine mass transfer coefficients and power consumption of commercial net spacers. The simulations show transversal and longitudinal vortices, vortex shedding and instationary flow behavior leading to the enhanced mass transfer in spacer filled-channels compared to empty channels. The results of the simulations were validated with experiments and compared with data reported in literature, showing satisfactory agreement. Furthermore, CFD simulations were used to optimize the geometry of commercial net spacers in terms of mass transfer and power consumption. The performance of these optimized spacer geometries will be used as reference for future work on the development of new high-performance spacer shapes
Quantum Oscillations in CuBiSe in High Magnetic Fields
CuBiSe has drawn much attention as the leading candidate to be
the first topological superconductor and the realization of coveted Majorana
particles in a condensed matter system. However, there has been increasing
controversy about the nature of its superconducting phase. This study sheds
light on present ambiguity in the normal state electronic state, by providing a
complete look at the quantum oscillations in magnetization in
CuBiSe at intense high fields up to 31T. Our study focuses on the
angular dependence of the quantum oscillation pattern in a low carrier
concentration. As magnetic field tilts from along the crystalline c-axis to
ab-plane, the change of the oscillation period follows the prediction of the
ellipsoidal Fermi surface. As the doping level changes, the 3D Fermi surface is
found to transform into quasi-cylindrical at high carrier density. Such a
transition is potentially a Lifshitz transition of the electronic state in
CuBiSe.Comment: 6 pages, 6 figures, submitted to Phys. Rev.
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