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161.
Reviews evolutionary models of corporate globalization, distinguishing between international and global firms. To define global leadership, a distinction is made between the content of the activities of leaders in corporations within industries, and the style in which they conduct their affairs. The role of perception in cross-cultural interaction and leadership style is demonstrated by reviewing cross-national research. Alternatives to corporate global leadership are also suggested. Two models of global leadership training designed by multinational corporations are presented. Recommendations for preparing corporate leadership for global business are offered. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
162.
Ahmed N Mirshekar-Syahkal B Kennish L Karachalias N Babaei-Jadidi R Thornalley PJ 《Molecular nutrition & food research》2005,49(7):691-699
Food and beverages contain protein glycation adducts--both early-stage adducts and advanced glycation endproducts. We determined the concentrations of glycation adducts in selected food and beverages by liquid chromatography with triple quadrupole mass spectrometric detection. Cola drink contained low concentrations of glycation free adducts, whereas pasteurised and sterilised milk were rich sources of heat-stable glycation adduct residues--Nepsilon-carboxymethyl-lysine and Nepsilon-carboxyethyl-lysine. Laboratory rodent food was a rich source of advanced glycation endproducts. Measurement of glycation adducts in 24 h urine samples of normal and diabetic rats indicated that < 10% of glycation adduct residue consumption was excreted. Induction of diabetes by streptozotocin led to a 2-fold increase in urinary excretion of Nepsilon-carboxymethyl-lysine and a 27-fold increase in urinary excretion of methylglyoxal-derived hydroimidazolone Ndelta-(5-hydro-5-methyl-4-imidazolon-2-yl)-ornithine - the latter was decreased by high-dose thiamine therapy that also prevented the development of nephropathy. We conclude that cola drinks are a poor source of glycation adduct whereas thermally processed milk is rich in glycation adducts. Dietary glycation adducts residues probably have low bioavailability. Experimental diabetes is associated with a marked increase in exposure to endogenous formation of methylglyoxal-derived hydroimidazolone which is linked to the development of diabetic nephropathy. 相似文献
163.
Roya Jamarani Matthew W. Halloran Kushal Panchal Jim A. Nicell Richard L. Leask Milan Marić 《乙烯基与添加剂工艺杂志》2021,27(4):821-832
A family of poly(caprolactone) (PCL)-based oligomeric additives was evaluated as plasticizers for poly(vinyl chloride) (PVC). We found that the entire family of additives, which consist of a PCL core, diester linker, and alkyl chain cap, were effective plasticizers that improve migration resistance. The elongation at break and tensile strength of the blends made with the PCL-based additives were comparable to blends prepared with diisononyl phthalate (DINP), a plasticizer typically used industrially, and diheptyl succinate (DHPS), an alternative biodegradable plasticizer. Increasing concentration was found to decrease glass transition temperature (Tg) and increase elongation at break, confirming their role as functional plasticizers. We found that all of the PCL-based plasticizers exhibited significantly reduced leaching into hexanes compared to DINP and DHPS. The PCL-based plasticizers with shorter carbon chain lengths reduced leaching more than those with longer carbon chain lengths. 相似文献
164.
Hassan B. Kazemian Kenneth White Dominic Palmer-Brown 《Expert systems with applications》2013,40(9):3412-3420
This paper is in the area of membrane proteins. Membrane proteins make up about 75% of possible targets for novel drugs discovery. However, membrane proteins are one of the most understudied groups of proteins in biochemical research because of technical difficulties of attaining structural information about transmembrane regions or domains. Structural determination of TM regions is an important priority in pharmaceutical industry, as it paves the way for structure based drug design.This research presents a novel evolutionary support vector machine (SVM) based alpha-helix transmembrane region prediction algorithm to solve the membrane helices in amino acid sequences. The SVM-genetic algorithm (GA) methodology is based on the optimisation of sliding window size, evolutionary encoding selection and SVM parameter optimisation. In this research average hydrophobicity and propensity based on skew statistics are used to encode the one letter representation of amino acid sequences datasets.The computer simulation results demonstrate that the proposed SVM-GA methodology performs better than most conventional techniques producing an accuracy of 86.71% for cross-validation and 86.43% for jack-knife for randomly selected proteins containing single and multiple transmembrane regions. Furthermore, for the amino acid sequence 3LVG, the proposed SVM-GA produces better alpha-helix region identification than PRED-TMR2, MEMSATSVM/MEMSAT3 and PSIPRED V3.0. 相似文献
165.
Conductivity is an important issue of water quality detection. Although there are a number of microfluidic liquid conductivity sensors, most of them were difficult to fabricate and required cleanroom facilities, which significantly increased the cost of sensors. Here, we presented a novel liquid conductivity sensor that was built on interdigitated copper electrodes. Microscale sensor electrodes can be fabricated through the modified microfabrication process without any help of cleanroom facilities. In comparison with FEA simulation and commercial conductivity device, measured results showed that the fabricated liquid conductivity sensor was able to measure a wide range of liquids. Considering the ease of fabrication and its low cost, the cleanroom-free fabricated sensors have much potential for water quality monitoring. 相似文献
166.
Mehdi Azizi Hassan Dianat‐Moghadam Roya Salehi Masoud Farshbaf Disha Iyengar Samaresh Sau Arun K. Iyer Hadi Valizadeh Mohammad Mehrmohammadi Michael R. Hamblin 《Advanced functional materials》2020,30(19)
Although considerable efforts have been conducted to diagnose, improve, and treat cancer in the past few decades, existing therapeutic options are insufficient, as mortality and morbidity rates remain high. Perhaps the best hope for substantial improvement lies in early detection. Recent advances in nanotechnology are expected to increase the current understanding of tumor biology, and will allow nanomaterials to be used for targeting and imaging both in vitro and in vivo experimental models. Owing to their intrinsic physicochemical characteristics, nanostructures (NSs) are valuable tools that have received much attention in nanoimaging. Consequently, rationally designed NSs have been successfully employed in cancer imaging for targeting cancer‐specific or cancer‐associated molecules and pathways. This review categorizes imaging and targeting approaches according to cancer type, and also highlights some new safe approaches involving membrane‐coated nanoparticles, tumor cell‐derived extracellular vesicles, circulating tumor cells, cell‐free DNAs, and cancer stem cells in the hope of developing more precise targeting and multifunctional nanotechnology‐based imaging probes in the future. 相似文献
167.
Two-dimensional dopant mapping in the scanning electron microscope (SEM) has recently attracted attention due to its ability to measure dopant levels rapidly with high spatial resolution while requiring little or no sample preparation. The dopant concentration could be derived from the energy distribution of secondary electrons emitted per doped region. However, the lack of reliable quantification, when standard SEM imaging is used, has so far hindered a wide application of the technique. This paper aims to resolve this problem with quantitative energy-filtering using a through-the-lens (TTL) detector in a field emission gun SEM (FEG-SEM). We have used the linear shift obtained in the SE energy distribution with variable specimen bias using sample containing copper wires, defined as the experimental detector response R(exp), to quantify the energy filtering. Using different experimental conditions, values of (2.42+/-0.04)相似文献
168.
Zahra Ghasemi Iman Sourinejad Hossein Kazemian Mojtaba Hadavifar Sohrab Rohani Habibollah Younesi 《Chemical Engineering Communications》2020,207(6):808-825
AbstractThe Na-P1 zeolite was produced from coal fly ash and modified with different environmental friendly surfactants. The potential of these green modified zeolites was investigated as adsorbents for Cr(VI) ions in a batch system. XRD, SEM, XRF, and ICP-AES analyses were used for the characterization of raw materials and zeolite samples. The environmental friendly modified zeolites successfully immobilized different toxic elements in their framework inhibiting the transfer of these toxic elements to the surrounding liquid phase. The effects of various operational parameters on Cr(VI) removal were studied. The Hexamethylenediamine (HDTMA) and Ammonyx KP (KP) modified zeolites had larger chromium removal potential than the other samples at all temperatures. The effectiveness of Cr(VI) ions elimination became greater as the pH decreased and the adsorbent dose increased. The Freundlich, Langmuir, and Dubinin–Radushkevich isotherms were fitted to the equilibrium data. The Dubinin–Radushkevich and Langmuir models gave a better fitness to equilibrium data of HDTMA-Na-P1 and KP-Na-P1, respectively. The positive and high ΔH° values showed the endothermic nature of the total Cr(VI) sorption procedure and indicated that Cr(VI) adsorption onto HDTMA-Na-P1 and KP-Na-P1 is a chemisorption. The negative ΔS° values also showed that chromium ions were stable on the surface of adsorbents. The adsorption potential of the developed eco-friendly KP-Na-P1 was higher than those of other adsorbents reported in the literature. 相似文献
169.
Experimental and computational study of microfluidic flow‐focusing generation of gelatin methacrylate hydrogel droplets
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This work presents the experimental and computational study of droplet generation for hydrogel prepolymer solution in oil using a flow‐focusing device. Effects of different parameters on hydrogel droplet generation and droplet sizes in a flow‐focusing device were investigated experimentally and computationally. First, three dimensional (3D) computational simulations were conducted to describe the physics of droplet formation in each regime and mechanism of three different regimes: squeezing, dripping, and jetting regime of hydrogel were investigated. Subsequently, the effects of viscosity, inertia force, and surface tension force on droplet generation, and droplet size were studied through these experiments. The experiments were carried out using different concentration of gelatin methacrylate (GelMA) hydrogel (5 wt % and 8 wt %) as the dispersed phase and two different continuous phase liquids (light mineral oil and hexadecane) with various concentrations of surfactant (0 wt %, 3 wt %, and 20 wt %). All experimental data was summarized by capillary number of dispersed phases and the continuous phases to characterize the different regimes of droplet generation and to predict the transition of dripping to a jetting regime for GelMA solution in flow‐focusing devices. It is shown that the transition of dripping to a jetting regime for GelMA happens at lower capillary numbers compared to aqueous solutions. Moreover, by increasing the viscous force of continuous phase or decreasing the interfacial force, the size of GelMA droplets was decreased. By controlling these parameters, the droplet sizes can be controlled between 30 μm and 200 μm, which are very suitable for cell encapsulation. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43701. 相似文献
170.
Roya Majidi 《Journal of Computational Electronics》2016,15(4):1263-1268
The encapsulation of small fullerenes into graphyne nanotubes was studied to investigate the possibility of band gap engineering in these nanotubes. The electronic properties of zigzag (4,0) and (5,0) graphyne nanotubes filled with small \(\hbox {C}_{20}\) and \(\hbox {C}_{30}\) fullerenes were studied using density functional theory. It was found that the zigzag (4,0) and (5,0) graphyne nanotubes were semiconductors. These graphyne nanotubes filled with \(\hbox {C}_{20}\) and \(\hbox {C}_{30}\) fullerenes were shown p-type and n-type semiconducting properties, respectively. The energy band gap was dependent on the number of the encapsulated fullerenes. Our results demonstrated the ability of band gap engineering through the encapsulation of small fullerenes into graphyne nanotubes. 相似文献