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1.
The increasing competitive pressures and speed of R&D and product innovation is prompting many multinational enterprise customers to outsource their core activities to suppliers. Despite organizational challenges due to cultural and physical separation from their partners, these are now charged with supplier-driven innovation. This study looks at key drivers of supplier innovativeness, examines the role of cross-national differences in shaping supplier innovativeness and examines the impact of this dimension on relationship performance in international customer–supplier relationships. Our findings from a large-scale survey of Taiwanese electronics suppliers provide evidence of the contribution of antecedents such as customer orientation, customer control and technological uncertainty to the enhancement of supplier innovativeness. Innovativeness contributes to increased customer dependence and improves relationship performance. Differences in knowledge bases stemming from different institutions are also tested in this study; we find that knowledge distance may be detrimental to the innovativeness-performance link in international exchange relationships.  相似文献   

2.
Consensus exists suggesting that advances in information and communication technologies are a major driver in restructuring Multinational Enterprises (MNEs) and their cross-border supply chain activities. However, the role of virtual interfirm integration and its antecedents, contingency conditions and its association with performance in international exchange relationship is not clearly specified. This study proposes that virtual interfirm integration can serve as an alternative governance mechanism for suppliers. Thus, we examine its drivers, moderators, and performance outcomes in international exchange relationships in the context of suppliers and their MNE customers. The empirical context is a study of 240 Taiwanese-based electronics equipment manufacturers. We explore the effect of communication culture, internal, inter-organizational, and environmental dimensions on virtual interfirm integration, and supplier performance in international exchange. We conclude by sharing our findings on the pertinence of virtual interfirm integration in the supplier–MNE buyer relationships.  相似文献   

3.
Objective: The main objective of this study was to develop and evaluate a W/O microemulsion formulation of troxerutin to improve its oral bioavailability.

Methods: The W/O microemulsion was optimized using a pseudo-ternary phase diagram and evaluated for physical properties. In vitro MDCK cell permeability studies were carried out to evaluate the permeability enhancement effect of microemulsion, and in vivo absorption of troxerutin microemulsion in the intestine was compared with that of solution after single-dose administration (56.7?mg/kg) in male Wistar rats.

Results: The optimal formulation consisted of lecithin, ethanol, isopropyl myristate and water (23.30/11.67/52.45/12.59 w/w) was physicochemical stable and the mean droplet size was about 50.20?nm. In vitro study, the troxerutin-loaded microemulsion showed higher intestinal membrane permeability across MDCK monolayer when compared with the control solution. The W/O microemulsion can significantly promote the intestinal absorption of troxerutin in rats in vivo, and the relative bioavailability of the microemulsion was about 205.55% compared to control solution.

Conclusion: These results suggest that novel W/O microemulsion could be used as an effective formulation for improving the oral bioavailability of troxerutin.  相似文献   

4.
It has been demonstrated in the past that observing the β-decay spectrum of 187Re with microbolometers provides a suitable method to determine the mass of the electron anti-neutrino from β-endpoint measurements. In a first step, with the experiment MIBETA a sensitivity of m νe≤15 eV/c2 was achieved. To compete with the sensitivity of m νe≤2.2 eV/c2 established by the Mainz/Troitsk tritium β-decay experiment and the limit of m νe≤0.2 eV/c2 aimed at with KATRIN, a new experiment MARE has been initiated. As a first stage (MARE-1), 300 detectors consisting of silicon implanted thermistors, produced by NASA/GSFC, and absorbers of AgReO4 crystals will be mounted. To optimize the experimental setup, a test array was equipped with 10 AgReO4 crystals of various size and shape. The influence of the crystal quality as well as of different types of resin on rise time and energy resolution was investigated.   相似文献   

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The aim was to prepare an optimized zolmitriptan (ZT)-loaded transfersome formulation using Box–Behnken design for improving the bioavailability by nasal route for quick relief of migraine and further to compare with a marketed nasal spray. Here, three factors were evaluated at three levels. Independent variables include: amount of soya lecithin (X1), amount of drug (X2) and amount of tween 80 (X3). The dependent responses were vesicle size (Y1), flexibility index (Y2) and regression coefficient of drug release kinetics (Y3). Prepared formulations were evaluated for physical characters and an optimal system was identified. Further, in vivo pharmacokinetic study was performed in male wistar rats to compare the amount of drug in systemic circulation after intranasal administration. Optimized ZT-transfersome formulation containing 82.74?mg of lecithin (X1), 98.37?mg of zolmitriptan (X2) and 32.2?mg of Tween 80 (X3) and had vesicle size of 93.3?nm, flexibility index of 20.25 and drug release regression coefficient of 0.992. SEM picture analysis revealed that the vesicles were spherical in morphology and had a size more than 1?µm. The formulations were found to be physically stable upon storage at room temperature up to 2?months period, as there were no significant changes noticed in size and ZP. The nasal bioavailability of optimized transfersome formulation was found to be increased by 1.72 times than that of marketed nasal spray (Zolmist®). The design and development of zolmitriptan as transfersome provided improved nasal delivery over a conventional nasal spray for a better therapeutic effect.  相似文献   

8.
Exploring innovative technologies to precisely quantify biomolecules is crucial but remains a great challenge for disease diagnosis. Unfortunately, the humoral concentrations of most biotargets generally vary within rather limited scopes between normal and pathological states, while most literature-reported biosensors can detect large spans of targets concentrations, but are less sensitive to small concentration changes, which consequently make them mostly unsatisfactory or even unreliable in distinguishing positives from negatives. Herein, a novel strategy of precisely quantifying the small concentration changes of a certain biotarget by editing the dynamic ranges and sensitivities of a lanthanide-based metal–organic framework (Eu-ZnMOF) biosensor is reported. By elaborately tailoring the biosensor's structure and surface areas, the tunable Eu-ZnMOF is developed with remarkably enhanced response slope within the “optimized useful detection window,” enabling it to serve as a powerful signal amplifier (87.2-fold increase) for discriminating the small concentration variation of urinary vanillylmandelic acid (an early pathological signature of pheochromocytoma) within only three times between healthy and diseased subjects. This study provides a facile approach to edit the biosensors' performances through structure engineering, and exhibits promising perspectives for future clinical application in the non-invasive and accurate diagnosis of severe diseases.  相似文献   

9.
This study investigates potentials of solid lipid nanoparticles (SLN)-based gel for transdermal delivery of tenoxicam (TNX) and describes a pharmacokinetic–pharmacodynamic (PK–PD) modeling approach for predicting concentration–time profile in skin. A 23 factorial design was adopted to study the effect of formulation factors on SLN properties and determine the optimal formulation. SLN-gel tolerability was investigated using rabbit skin irritation test. Its anti-inflammatory activity was assessed by carrageenan-induced rat paw edema test. A published Hill model for in vitro inhibition of COX-2 enzyme was fitted to edema inhibition data. Concentration in skin was represented as a linear spline function and coefficients were estimated using non-linear regression. Uncertainty in predicted concentrations was assessed using Monte Carlo simulations. The optimized SLN was spherical vesicles (58.1?±?3.1?nm) with adequate entrapment efficiency (69.6?±?2.6%). The SLN-gel formulation was well-tolerated. It increased TNX activity and skin level by 40?±?13.5, and 227?±?116%, respectively. Average Cmax and AUC0–24 predicted by the model were 2- and 3.6-folds higher than the corresponding values computed using in vitro permeability data. SLN-gel is a safe and efficient carrier for TNX across skin in the treatment of inflammatory disorders. PK–PD modeling is a promising approach for indirect quantitation of skin deposition from PD activity data.  相似文献   

10.
Ti-based biocompatible alloys are especially used for replacing failed hard tissue. Some of the most actively investigated materials for medical implants are the beta-Ti alloys, as they have a low elastic modulus (to inhibit bone resorption). They are alloyed with elements such as Nb, Ta, Zr, Mo, and Fe. We have prepared a new beta-Ti alloy that combines Ti with the non-toxic elements Ta and Mo using a vacuum arc-melting furnace and then annealed at 950 degrees C for one hour. The alloy was finally quenched in water at room temperature. The Ti-12Mo-5Ta alloy was characterised by X-ray diffraction, optical microscopy, SEM and EDS and found to have a body-centred-cubic structure (beta-type). It had a lower Young's modulus (about 74 GPa) than the classical alpha/beta Ti-6Al-4V alloy (120 GPa), while its Vickers hardness remained very high (about 303 HV). This makes it a good compromise for a use as a bone substitute. The cytocompatibility of samples of Ti-12Mo-5Ta and Ti-6Al-4V titanium alloys with various surface roughnesses was assessed in vitro using organotypic cultures of bone tissue and quantitative analyses of cell migration, proliferation and adhesion. Mechanically polished surfaces were prepared to produce unorientated residual polished grooves and cells grew to a particularly high density on the smoother Ti-12Mo-5Ta surface tested.  相似文献   

11.
China's shale gas development has had a good start. It is necessary that the developers take advantage of the opportunity to make further efforts to promote shale gas development in China, in particular by rolling out a comprehensive plan on a national level. The author makes a proposal to establish a special shale gas test area in and adjacent to the Sichuan Basin as the most important way to promote the rapid development of shale gas in China. For this purpose, the author analyzes the current situation and problems of shale gas development in China, addresses the necessity and feasibility of establishing a special test area for shale gas development, and draws up the scope of this shale gas special test area of about 450 thousand square kilometers, covering Sichuan, Chongqing, Guizhou, and part of Yunnan, Hunan, Hubei provinces, and proposes the establishment of a shale gas test area in China. This consists of an overall plan, targets, and contents in 10 aspects, along with organization and implementation modes. The shale gas exploration and development in the shale gas zones is promoted vigorously by introducing special policies and innovating exploration, development and utilization model. While at the same time, the shale gas zones of continental facies in the Ordos Basin and marineterrigenous facies in South Hubei Basin will be established.The experiences of the reform in the shale gas zones will be the good practice for the reform of petroleum organization system.  相似文献   

12.
Many interactive systems offer assistance when users have difficulties in operating or using them. In spite of the overwhelming variety of assistance techniques available, it is often unclear what type of assistance is really needed and how special assistance functions should be designed. The first step towards theoretically solid design decisions is a conceptual framework and a comprehensive taxonomy of assistance. This paper proposes to define assistance as access to machine functions and provides a taxonomy based mainly on action stages to be assisted. These stages are: (1) motivation, activation and goal setting; (2) perception; (3) information integration, generating situation awareness; (4) decision-making, action selection; (5) action execution; and (6) processing feedback of action results. In analogy to social assistance, various types of technical assistance are assigned to the six action stages. As additional dimensions to classify assistance, we also discuss adjustment, initiative, presentation media and input modality.  相似文献   

13.
Technical Physics Letters - The main features of a continuous open discharge used to generate electron beams in medium-pressure gases are discussed. I–V characteristics have been...  相似文献   

14.
Radiochemistry - The technology of fractionation of trans-plutonium elements (TPEs) and REEs with the use of 0.15 M TODGA (tetraoctylamide of diglycolic acid) + 5% n-decanol in Isopar-M as...  相似文献   

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A new simulation method was developed for analyzing the grinding mechanisms of aggregates in wet ball milling. The calculation of the following five behaviors is needed in this case: dynamics and breakage behaviors of aggregates, collisions of aggregates, a motion of fluid including aggregates, ball-fluid interaction forces and aggregate-fluid interaction forces. The dynamic and breakage behaviors of aggregates were calculated by advanced discrete element method (ADEM). The collisions of aggregates were represented by DEM. The motion of fluid including aggregates was solved by spatially-averaged equations of the fluid with finite difference method (FDM). The ball-fluid interaction forces were calculated by immersed boundary method (IBM). The model for the aggregate-fluid interaction forces has not been established, so that a new simulation model for estimating them was developed and named ADEM-computational fluid dynamics (ADEM-CFD) model. The ADEM-CFD model was verified by comparing the fluid drag coefficients obtained by White’s equation. The new simulation method considering the five behaviors was validated by comparing with an experiment about dynamic and breakage behaviors of aggregates around a falling ball in liquid. It is found that the new simulation method proposed could analyze the dynamic and breakage behaviors of aggregates in wet ball milling.  相似文献   

17.
Geng  Diancheng  Yu  Hao  Kondo  Sosuke  Kasada  Ryuta 《Journal of Materials Science》2022,57(28):13736-13755
Journal of Materials Science - Nanoindentation hardness tests are used to measure indentation hardness at the micro- and nanoscales and further to predict Vickers hardness on larger scales. Hence,...  相似文献   

18.
Miller J  Yu XB  Yu PK  Cringle SJ  Yu DY 《Applied optics》2011,50(6):876-885
Ultraviolet (UV) lasers have the capability to precisely remove tissue via ablation; however, due to strong absorption of the applicable portion the UV spectrum, their surgical use is currently limited to extraocular applications at the air/tissue boundary. Here we report the development and characterization of a fiber-optic laser delivery system capable of outputting high-fluence UV laser pulses to internal tissue surfaces. The system has been developed with a view to intraocular surgical applications and has been demonstrated to ablate ocular tissue at the fluid/tissue boundary. The fifth (213?nm) and fourth(266?nm) harmonics of a Nd:YAG laser were launched into optical fibers using a hollow glass taper to concentrate the beam. Standard and modified silica/silica optical fibers were used, all commercially available. The available energy and fluence as a function of optical fiber length was evaluated and maximized. The maximum fluence available to ablate tissue was affected by the wavelength dependence of the fiber transmission; this maximum fluence was greater for 266?nm pulses (8.4?J/cm2) than for 213?nm pulses (1.4?J/cm2). The type of silica/silica optical fiber used did not affect the transmission efficiency of 266?nm pulses, but transmission of 213?nm pulses was significantly greater through modified silica/silica optical fiber. The optical fiber transmission efficiency of 213?nm pulses decreased as a function of number of pulses transmitted, whereas the transmission efficiency of 266?nm radiation was unchanged. Single pulses have been used to ablate fresh porcine ocular tissue. In summary, we report a method for delivering the fifth (213?nm) and fourth (266?nm) harmonics of a Nd:YAG laser to the surface of immersed tissue, the reliability and stability of the system has been characterized, and proof of concept via tissue ablation of porcine ocular tissue demonstrates the potential for the intraocular surgical application of this technique.  相似文献   

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A new biodegradable magnesium–zinc–strontium (Mg–Zn–Sr) alloy was developed and studied for medical implant applications. This first study investigated the alloy processing (casting, rolling, and heat treatment), microstructures, mechanical properties, and degradation properties in simulated body fluid (SBF). Aging treatment of the ZSr41 alloy at 175 °C for 8 h improved the mechanical properties when compared to those of the as-cast alloy. Specifically, the aged ZSr41 alloy had an ultimate tensile strength of 270 MPa, Vickers hardness of 71.5 HV, and elongation at failure of 12.8%. The mechanical properties of the ZSr41 alloy were superior as compared with those of pure magnesium and met the requirements for load-bearing medical implants. Furthermore, the immersion of the ZSr41 alloy in SBF showed a degradation mode that progressed cyclically, alternating between pitting and localized corrosion. The steady-state average degradation rate of the aged ZSr41 alloy in SBF was 0.96 g/(m2·hr), while the pH of SBF immersion solution increased. The corrosion current density of the ZSr41 alloy in SBF solution was 0.41 mA/mm2, which was much lower than 1.67 mA/mm2 for pure Mg under the same conditions. In summary, compared to pure Mg, the mechanical properties of the new ZSr41 alloy improved while the degradation rate decreased due to the addition of Zn and Sr alloying elements and specific processing conditions. The superior mechanical properties and corrosion resistance of the new ZSr41 alloy make it a promising alloy for next-generation implant applications.  相似文献   

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