5,517 research outputs found

    The effect of explicit and tacit synergies on alliances radical innovation: The moderating roles of interfirm technological diversity and environmental technological dynamism

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    This study draws on theories of organizational inertia and relational view to examine how the pursuit of partnership synergy influences radical innovation in different technological contexts. We differentiate between two types of synergy: explicit synergy, defined as the potential to exchange interfirm operational elements to renew processes or capabilities, and tacit synergy, conceptualized as the potential to synthesize cross-boundary resources to develop new perspectives or thinking modes. We find that both explicit and tacit synergy have positive impacts on radical innovation, and such impacts are contingent on interfirm technological diversity and environmental technological dynamism in opposing ways. Specifically, environmental technological dynamism positively moderates the relationship between explicit synergy and radical innovation but not the relationship between tacit synergy and radical innovation. In contrast, interfirm technological divers ity positively moderates the relationship between tacit synergy and radical innovation but not the relationship between explicit synergy and radical innovation. Our study sheds new light on the generation of radical innovation in alliances. It also provides practitioners with useful guidelines for crafting synergy strategies that will facilitate the pursuit of radical innovation

    Split Bregman Method for Sparse Inverse Covariance Estimation with Matrix Iteration Acceleration

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    We consider the problem of estimating the inverse covariance matrix by maximizing the likelihood function with a penalty added to encourage the sparsity of the resulting matrix. We propose a new approach based on the split Bregman method to solve the regularized maximum likelihood estimation problem. We show that our method is significantly faster than the widely used graphical lasso method, which is based on blockwise coordinate descent, on both artificial and real-world data. More importantly, different from the graphical lasso, the split Bregman based method is much more general, and can be applied to a class of regularization terms other than the â„“1\ell_1 nor

    An Updated Meta-Analysis: Risk Conferred by Glutathione S-Transferases ( GSTM1

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    Purpose. To study the effects of glutathione S-transferase M1 (GSTM1) and T1 (GSTT1) polymorphisms on age-related cataract (ARC). Methods. After a systematic literature search, all relevant studies evaluating the association between GSTs polymorphisms and ARC were included. Results. Fifteen studies on GSTM1 and nine studies on GSTT1 were included in this meta-analysis. In the pooled analysis, a significant association between null genotype of GSTT1 and ARC was found (OR = 1.229, 95% CI = 1.057–1.429, and P=0.007). In subgroup analysis, the association between cortical cataract (CC) and GSTM1 null genotype was statistically significant (OR = 0.713, 95% CI = 0.598–0.850, and P<0.001). In addition, GSTM1 null genotype was significantly associated with ARC causing risk to individuals working indoors and not individuals working outdoors. The association between GSTT1 null genotype and risk of ARC was statistically significant in Asians (OR = 1.442, 95% CI = 1.137–1.830, and P=0.003) but not in Caucasians. Conclusions. GSTM1 positive genotype is associated with increased risk of CC and loses the protective role in persons who work outdoors. Considering the ethnic variation, GSTT1 null genotype is found to be associated with increased risk of ARC in Asians but not in Caucasians

    Effect of Samarium doping on the nucleation of fcc-Aluminum in undercooled liquids

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    The effect of Sm doping on the fcc-Al nucleation was investigated in Al-Sm liquids with low Sm concentrations (xSm) with molecular dynamics simulations. The nucleation in the moderately undercooled liquid is achieved by the recently developed persistent-embryo method. Systematically computing the nucleation rate with different xSm (xSm=0%, 1%, 2%, 3%, 5%) at 700 K, we found Sm dopant reduces the nucleation rate by up to 25 orders of magnitudes with only 5% doping concentration. This effect is mostly associated with the increase in the free energy barrier with a minor contribution from suppression of the attachment to the nucleus caused by Sm doping.Comment: 4 figure

    Visualization and quantitation of fetal movements by real-time three-dimensional ultrasound with live xPlane imaging in the first trimester of pregnancy

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    AIM: To prove whether real-time three-dimensional (3D) ultrasound with live xPlane imaging is better in observing fetal movements than standard ultrasound imaging. METHODS: 50 healthy women with singleton pregnancies (22-43 years old) at 11 to 14 weeks of gestation underwent real-time 3D ultrasound examination with live xPlane imaging from July 2014 to February 2015. The incidence and frequency of 10 fetal movement patterns in 10 minutes were evaluated, including general movements (GMs), isolated arm movements, isolated leg movements, hiccup, stretching, breathing, startle, jaw opening, isolated head retroflexion, and isolated head anteflexion. The correlation between gestational age and frequency of each fetal movement pattern was analyzed. RESULTS: GM had the highest incidence (100%), followed by startle (84%) and isolated arm movements (68%). Their median frequency was 5 (IQR 3-6), 5 (IQR 1.75-11.5), and 1 (IQR 0-2), respectively. GM (Z = 5.875, P < 0.001) and startle (Z = 5.302, P < 0.001) had significantly higher frequency than isolated arm movements. The other 7 fetal movement patterns had much lower incidence and frequency. The frequency of GM was positively correlated with gestational age (r = 0.360, P = 0.010). CONCLUSION: Real-time 3D ultrasound with live x Plane imaging was shown to be a feasible tool for observing fetal movements

    A self-contained algorithm for determination of solid-liquid equilibria in an alloy system

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    We describe a self-contained procedure to evaluate the free energy of liquid and solid phases of an alloy system. The free energy of a single-element solid phase is calculated with thermodynamic integration using the Einstein crystal as the reference system. Then, free energy difference between the solid and liquid phases is calculated by Gibbs-Duhem integration. The central part of our method is the construction of a reversible alchemical path connecting a pure liquid and a liquid alloy to calculate the mixing enthalpy and entropy. We have applied the method to calculate the free energy of solid and liquid phases in the Al-Sm system. The driving force for fcc-Al nucleation in Al-Sm liquid and the melting curve for fcc-Al and Al3Sm are also calculated.Comment: 15 pages, 7 figures, submitting to a journa
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