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ABSTRACT Conventional foreign direct investment (FDI) theories regard FDIs as strategic moves based on operational or industrial organization considerations. We demonstrate that financial factors are also important in corporate FDI... more
ABSTRACT Conventional foreign direct investment (FDI) theories regard FDIs as strategic moves based on operational or industrial organization considerations. We demonstrate that financial factors are also important in corporate FDI decisions. The financial factors concern internal capital market strength and corporate governance and include exchange rate changes, internal and external financing cost, risk diversification, and agency costs. There is variability in the significance of financial variables depending on industries and destinations. The integrated model with both strategic and financial factors is superior to either component model in explaining FDIs. However, financial factors are no less important in explaining the prevailing FDI phenomena than strategic or operational variables.
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... E. W. Tsai, T. Pajkossy,? K. Rajeshwar,* and J. R. Reynolds* Department of Chemistry, The University of Texas at Arlington, Arlington, Texas 7601 9 (Received: August 20, 1987; In Final Form: January 11, 1988) ... 225. 273. (10) Tsai:... more
... E. W. Tsai, T. Pajkossy,? K. Rajeshwar,* and J. R. Reynolds* Department of Chemistry, The University of Texas at Arlington, Arlington, Texas 7601 9 (Received: August 20, 1987; In Final Form: January 11, 1988) ... 225. 273. (10) Tsai: E. W.; Jang, G.-W.; Rajeshwar, K. J. Chem. ...
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Evaporative light scattering (ELS) and refractive index (RI) detection methods were evaluated for the determination of surface-bound hydroxypropylcellulose (HPC) on drug particles in colloidal dispersions. Size exclusion chromatography... more
Evaporative light scattering (ELS) and refractive index (RI) detection methods were evaluated for the determination of surface-bound hydroxypropylcellulose (HPC) on drug particles in colloidal dispersions. Size exclusion chromatography (SEC) was used to separate HPC from other components of the dispersions. The instrumental parameters of the ELS detector were optimized to obtain maximum peak intensity, adequate peak shape and minimal baseline noise by varying the mobile phase flow rate, nebulizer temperature, and evaporation temperature. The chromatographic method was validated using both detectors. The ELS detector response exhibited second order polynomial and linear double logarithmic correlation with concentration over a 10-300% range while the RI response was linear. The double logarithmic correlation simplified the calculation compared to using the polynomial fit, and it provided more accurate results compared to the linear fit approach. Total HPC was obtained by solubilizing all components of the dispersion and analyzing for HPC. Non-bound HPC was obtained by ultracentrifuging the dispersion and analyzing the supernatant for HPC concentration. Analysis for total- and non-bound HPC in a representative colloidal dispersion gave method precisions with R.S.D.s of 2.5 and 2.2% for ELS, and 4.5 and 2.4% for RI (n=4). HPC bound to the surface of the drug particles was determined by difference: % bound HPC=100%-% non-bound HPC. Resultant % bound HPC values ranged from 22.1 to 25.4% of available HPC. Both ELS and RI are satisfactory detection techniques for HPC quantitation and for determination of the proportion of HPC bound to drug colloid particles, and the assay results are comparable.
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Research Interests: Analytical Chemistry, Chemometrics, Electronics, Principal Component Analysis, Pharmaceutical Technology, and 16 morePharmaceutical Chemistry, Stability, Quantitative analysis, Dosage Form, Identification, SHELF LIFE, Raw materials, Pharmaceutical, Electronic Nose, Product Development, Genetic analysis for qualitative and quantitative traits of crop plants, Data Processing, Quantitative Analysis, Quantitative Method, Partial Least Square, and Pharmaceutical Formulation
Electrochemistry of some β‐Substituted Polythiophenes. [Journal of The Electrochemical Society 136, 3683 (1989)]. Eric W. Tsai, Sanjay Basak, Jose P. Ruiz, John R. Reynolds, Krishnan Rajeshwar. Abstract. The anodic electrochemistry ...
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Information on the effect of stress on the allele-specific expression (ASE) profile of rice hybrids is limited. More so, the association of allelically imbalanced genes to important traits is yet to be understood. Here we assessed allelic... more
Information on the effect of stress on the allele-specific expression (ASE) profile of rice hybrids is limited. More so, the association of allelically imbalanced genes to important traits is yet to be understood. Here we assessed allelic imbalance (AI) in the heterozygote state of rice under non- and water-stress treatments and determined association of asymmetrically expressed genes with grain yield (GY) under drought stress by in-silico co-localization analysis and selective genotyping. The genotypes IR64, Apo and their F1 hybrid (IR64 × Apo) were grown under normal and water-limiting conditions. We sequenced the total RNA transcripts for all genotypes then reconstructed the two chromosomes in the heterozygote. We are able to estimate the transcript abundance of and the differential expression (DE) between the two parent-specific alleles in the rice hybrids. The magnitude and direction of AI are classified into two categories: (1) symmetrical or biallelic and (2) asymmetrical. Th...
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... Wastes from Metal Plating Operations ERIC CHAI-EI TSAI and ROY NIXON Environmental Protection Conservation and Protection Western and Northern Region Environment Canada 499998 Avenue Edmonton, Alberta Canada T6B 2X3 ABSTRACT ...
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Research Interests: Analytical Chemistry, Catalysis, Kinetics, Mass Spectrometry, Dosage Form, and 11 morePharmaceutical, Relative Humidity, High Pressure Liquid Chromatography, Qualitative Analysis, Liquid Chromatography, Tablets, Gas Chromatography/mass Spectrometry, Losartan, Chemical Stability, Drug Stability, and Aldehydes
Application of ion chromatography (IC) to the analysis of non-chromophoric bisphosphonate drugs in pharmaceutical dosage formulations is described. The method is based on the use of single-column ion chromatography in conjunction with... more
Application of ion chromatography (IC) to the analysis of non-chromophoric bisphosphonate drugs in pharmaceutical dosage formulations is described. The method is based on the use of single-column ion chromatography in conjunction with indirect UV detection that obviates the need for tedious chemical derivatization procedures. Diluted drug samples are chromatographed directly on a Waters IC-Pak HR anion-exchange column with dilute nitric acid (1.6-12 mM) as the mobile phase which exhibits a UV absorption maximum near 220 nm. Analyte detection is monitored by measuring the decrease in absorption of the mobile phase. The IC method has been validated and shown to be precise, accurate, specific and rugged for routine assay. Application of the method to the determination of alendronate sodium tablets, etidronate disodium injectable (which requires an eluent pH control for chromatographic resolution of active drug from chloride ions) and clodronate disodium injectable is presented. The performances of the Waters IC-Pak HR and several equivalent columns are also discussed.
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Poloxamers have been used as functional excipients in pharmaceutical products. They function as surfactants, emulsifying agents, solubilizing agents, dispersing agents, and in vivo absorbance enhancer. Despite their wide range of... more
Poloxamers have been used as functional excipients in pharmaceutical products. They function as surfactants, emulsifying agents, solubilizing agents, dispersing agents, and in vivo absorbance enhancer. Despite their wide range of applications, limited analytical techniques have been reported in literature for characterizing poloxamers and few are targeted to quantify poloxamer contents in formulations with desired sensitivity and accuracy. In this paper, two distinct analytical methods for quantifying low levels of poloxamers in pharmaceutical formulations have been developed and optimized: a colorimetric method and a size exclusion chromatography method. The colorimetric method is based on the formation of a colored complex between poloxamers and cobalt(II) thiocyanate in aqueous medium, which has a maximum UV absorbance at 624 nm. The feasibility of this method is product specific. In this report, adequate specificity and sensitivity was demonstrated for only one of the several products tested. The size exclusion chromatography (SEC) method utilizes size exclusion columns with THF as mobile phase and refractive index detection. The SEC method provides a limit of quantitation (LOQ) of 0.005 mg/mL (0.0005%, w/w) and at least three orders of magnitudes of linear range. We applied the SEC method to pharmaceutical products containing 0.3-10% poloxamer 188 or poloxamer 407, such as Avapro, Neurontin, Sudafed and other developmental formulations. The results obtained with the SEC method agreed very well with literature and theoretical values with 97-102% recovery. The SEC method was proven to be widely applicable, accurate, precise and simple to use.
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... Martin Pomerantz,* Dennis S. Marynick,* Krishnan Rajeshwar,* Whe-Narn Chou, Linda Throckmorton, Eric W. Tsai, Patty C. Y. Chen, and Terry Cain Department of Chemistry, The University of Texas at Arlington, Arlington, Texas 76019-0065... more
... Martin Pomerantz,* Dennis S. Marynick,* Krishnan Rajeshwar,* Whe-Narn Chou, Linda Throckmorton, Eric W. Tsai, Patty C. Y. Chen, and Terry Cain Department of Chemistry, The University of Texas at Arlington, Arlington, Texas 76019-0065 ... _ _ _ _ ~ (24) Bremser, W.; Ernst, ...
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The interaction between copper interconnects and low-k hydrogen silsesquioxane (HSQ) film was investigated using a Cu/HSQ/Si metal insulation semiconductor capacitor and deuterium plasma post-treatment. Owing to serious diffusion of... more
The interaction between copper interconnects and low-k hydrogen silsesquioxane (HSQ) film was investigated using a Cu/HSQ/Si metal insulation semiconductor capacitor and deuterium plasma post-treatment. Owing to serious diffusion of copper atoms in HSQ film, ...
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Journal of Chromatography, 626 (1992) 245-250 Elsevier Science Publishers BV, Amsterdam CHROM. 24 557 Application of capillary electrophoresis to pharmaceutical analysis Determination of alendronate in dosage forms Eric W. Tsai, Manohar... more
Journal of Chromatography, 626 (1992) 245-250 Elsevier Science Publishers BV, Amsterdam CHROM. 24 557 Application of capillary electrophoresis to pharmaceutical analysis Determination of alendronate in dosage forms Eric W. Tsai, Manohar M. Singh, Hannah H. Lu, Dominic ...
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A method was developed and validated for the direct determination in pharmaceutical dosage formulations of alendronate, a non-chromophoric compound. It is based on the use of single-column ion chromatography with conductivity detection... more
A method was developed and validated for the direct determination in pharmaceutical dosage formulations of alendronate, a non-chromophoric compound. It is based on the use of single-column ion chromatography with conductivity detection that obviates the need for the tedious chemical derivatization procedures that are required for UV and fluorescence detection. Diluted samples of 0.05 mg/ml were chromatographed directly on a Waters IC-Pak HR anion-exchange column or a Dionex OmniPac PAX-100 column with dilute nitric acid as the mobile phase followed by conductivity detection. The method was validated and shown to be precise, accurate and specific for the assay of alendronate in intravenous (i.v.) solution and tablet formulations. The ruggedness of the assay was studied by generating data from four different instruments. Also established was the equivalence between this method and a previously reported high-performance liquid chromatographic method with 9-fluorenylmethyl chloroformate derivatization and UV detection. Application of the method to the determination of alendronate in i.v. and tablet formulations is presented and the performances of the Waters IC-Pak HR and Dionex OmniPac columns are discussed.
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... Po-Tsun LIU 1, Ting-Chang CHANG 2,3, Ya-Liang YANG 3, Yi-Fang CHENG 4, Fu-Yung SHIH 5, ... Due to the interaction between copper and HSQ film that occurred, slight increases in the leakage current and dielectric constant were observed... more
... Po-Tsun LIU 1, Ting-Chang CHANG 2,3, Ya-Liang YANG 3, Yi-Fang CHENG 4, Fu-Yung SHIH 5, ... Due to the interaction between copper and HSQ film that occurred, slight increases in the leakage current and dielectric constant were observed in the electrical characteristics of ...
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CGE is a well-established separation technique for the analysis of biologically important molecules such as nucleic acids. The inherent high resolving power, rapid analysis times, excellent detection sensitivity, and quantification... more
CGE is a well-established separation technique for the analysis of biologically important molecules such as nucleic acids. The inherent high resolving power, rapid analysis times, excellent detection sensitivity, and quantification capabilities makes this method favorable compared to conventional manual polyacrylamide and agarose slab gel electrophoresis techniques. In this paper we introduce a novel single-channel capillary gel electrophoresis system with LED-induced fluorescence detection also utilizing a compact pen-shaped capillary cartridge design for automatic analysis of samples from a 96-well plate. To evaluate the suitability of the system, 1000 genomic DNA(gDNA) samples were analyzed in gel filled capillaries and detected by the microball ended excitation and emission optical fiber based LED-induced fluorescence detection system. Excellent migration time reproducibility of RSD <0.75% was obtained over the course of 1000 runs. The system rapidly distinguished between intact and degraded gDNA samples, therefore provided important information if they could be used for downstream quantitative PCR processing where high-quality intact gDNA was key. We envision that this novel system design will rapidly find new applications in both research and clinical diagnostic laboratories as a highly sensitive and easy to use bio-analytical approach.