cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.14457/cu.the.2009.1599
title: Effects of vibration exercise in comparison to resistance exercise on leg muscle strength and ankle joint proprioception in elderly Thai women

description: Objectives: To study effects of vibration exercise on leg muscle strength and ankle joint proprioception in elderly Thai women. Methods: The subjects were healthy elderly Thai women aged between 55-65 years. 45 subjects were assigned into 3 groups: a vibration exercise or VE group (n = 17), a resistance exercise or RE group (n = 16), and a control or C group (n = 12). All 3 groups were trained on leg muscle 3 times/week for 3 months. The VE group performed leg muscle exercise by performing high squat stance with knee-flexed 160° on vibration platform. The RE group trained their leg muscle by performing leg extension and leg curl while the C group trained their leg muscle by performing high squat stance with knee-flexed 160° on smooth and stable floor. At the beginning and the end of the 12-week program, all subjects were involved in 3 measurements: quadriceps and hamstrings muscle strength test in Isometric test by Biodex System 3, ankle joint proprioception (inversion and plantarflextion) test by Ankle Movement Extent Discrimination Apparatus (AMEDA) and balance assessment of A-P CoP excursion and Lateral CoP excursion with eyes-opened and –closed on hard and soft surface by standing on a force platform (BalanceCheck®). Results: The vibration exercise and resistance exercise groups significantly increased their quadriceps and hamstrings muscle strength (p &lt; 0.05) after training. It revealed that the resistance exercise group significantly increased in quadriceps muscle strength comparing among 3 groups. In addition, no significant differences among 3 groups were found in ankle joint proprioception test and balance assessments. Conclusion: Vibration exercise increases leg muscle strength after the 12-week training. However, resistance exercise has more effectiveness than vibration exercise in comparison with the 3 groups.
DOI: 10.14457/cu.the.2009.1600
title: The development of occupational health and safety management model for the informal-sector workers using a participatory approach

description: The purpose of this study was to develop and implement the Occupational Health and Safety Management (OHSM) Model for informal-sector workers using a participatory approach. This model consists of four processes: (1) capacity building, (2) risk analysis, (3) problem prevention and solving, and (4) monitoring and communication. This study used a Participatory Action Research (PAR)approach. The participants in the study were from eight local occupations from different regions in Thailand, including wood carving and ceramic making groups from the North, artificialflower making and plastic weaving groups from the Central region, handloom weaving and blanket making groups from the Northeast, batik making and pandanus weaving groups from the South. The research measures used in this study included job safety and risk assessments, industrial hygiene instruments, checklists, questionnaires, group discussions, community culture evaluations, and effectiveness evaluations of the OHSM Model application. Moreover, the occupational health and safety (OHS) database program was designed in order to facilitate the stakeholders’ involvement. The results showed that, after the sampled groups underwent the OHSM Model process, the post-test average scores on (1) the occupational health and safety knowledge, attitudes, and behavior measurement and (2) the work practice improvement measurement were significantly higher than the level of the pre-test average scores (p&lt;0.05). The degree of risk after undergoing the model process was decreased. The working conditions of the informal-sector workers were improved and met required standards. The results of the community culture measurement revealed that the safety culture, values, and beliefs (the workers’confidence in their group leaders) supported the application of the OHSM Model. However,the differences in clothing style and regional locations did not affect the effectiveness of the model. The effectiveness of the model in all groups was higher than 80 percent. The results showed that the average score of attitudes towards the usability of the OHS database program was good (2.71 +-.0.29). This model encouraged the use of local networks, which led to cooperation within the working groups in order to create appropriate technologies to precisely serve the needs of each group. The results demonstrated that the OHSM Model could effectively be applied to other informal-sector workers and improve occupational health and safety on a broader scale.
DOI: 10.14457/cu.the.2009.1601
title: Effects of situational variables on willingness to communicate and English classroom communication behaviors of ninth grade students

description: The objectives of the present study were to investigate the effects of situational variables on willingness to communicate and English classroom communication behavior of ninth grade students. The situational variable examined in this study were topic familiarity, group cohesiveness, and conversational contexts. The participants were eight ninth-grade students who were studying in the second semester of the academic year 2009 at a public secondary school in Chon Buri province. The data were collection over the period of nine weeks. The research instruments employed in this study were four questionnaires used to measure willingness to communicate, English classroom communication behaviors, topic familiarity, and group cohesiveness; English communicative instruction; classroom observation scheme; and stimulated recall. The findings indicated that willingness to communicate and English classroom communication behaviors were affected by topic familiarity, group cohesiveness and some conversational contexts. The participants were found to have willingness to communicate and perform communication behaviors in situations such as in the lessons that they were familiar with the topic, when being in a cohesive group, in an English-speaking environment, when the participants did not know the answer and someone spoke out, in enjoyable atmosphere, when there was a sense of competition, and when other people made mistake. In contrast, the participants lacked willingness to communicate and did not communicate when they made a mistake and were interrupted by other people.
DOI: 10.14457/cu.the.2009.1602
title: Encapsulation of clindamycin in alginate-chitosan microspheres by electrospray

description: This research focused on the production of alginate/chitosan nanospheres by electrospray technique. The parameters affected size and size distribution, such as voltage, flow rate, needle gauge and working distance were investigated. The result showed that increasing voltage and needle gauge resulted in a decrease in the sphere size. Whereas when increasing the flow rate and working distance, the sphere size were increased. The optimum condition for producing the clindamycinalginate/ chitosan nanosphere were as follows: voltage of 15 kV, flow rate of 10 mL/h, needle gauge of 26g and working distance of 8 cm. The average size was 855 nm. The morphology of alginate/chitosan nanospheres were spherical shape with smooth surface. Moreover the spherical size increased but not statistically significant when the drug content in the sphere was increased. Encapsulation efficiency of 83% was successfully achieved and up to 70.35% of clindamycin was released from the nanospheres into phosphate buffer pH 7.4 at 37ºC within the period of 12 hours. Finally, a simulated skin permeation study of the clindamycin from alginate/chitosan nanospheres using cellulose membrane demonstrated that clindamycin was continuously released from the spheres for up to 12 hours of study. The clindamycinalginate/ chitosan nanospheres have antibacterial activity on Staphylococcus aureus.
DOI: 10.14457/cu.the.2009.1603
title: Development of gas sensor from conducting polymer composite containing poly (3,4-ethylenedioxythiophene)

description: This research aims to study film processing of the conducting polymer composites containing poly(3,4-ethylenedioxythiophene) (PEDOT) using solid state polymerization of 2,5-dibromo-3,4-ethylenedioxythiophene (DBEDOT) in the polymer matrix on the interdigitated electrode (IDE) for gas sensing applications. The most appropriate condition for preparing DBEDOT-containing composite film was to spin casting the mixed solution of polybutadiene (PB) and DBEDOT dissolved in toluene at 1:10 (w/w) of PB:DBEDOT on IDE with a spin speed of 1500 rpm for 60 sec, and induced SSP of DBEDOT to conductive PEDOT by heating the PB/DBEDOT composite film at 60 oC for 8 h. The PB/PEDOT composite film having a resistance of 103 ohm was chosen for testing against a number of volatile chemicals. The resistivity of the PB/PEDOT composite film was systematically changed with the polarity of the chemical. The PEDOT-based sensor gave good responses to polar solvents such as methanol, ethanol, and water. The repeatability and sensitivity of the developed sensor were also determined.
DOI: 10.14457/cu.the.2009.1604
title: Mechanical properties of HDPE/CaCO3/ethylene-octene copolymer composites

description: Effects of nano-sized CaCO3 particles and Ethylene-Octene Copolymer (EOC) contents on mechanical properties and compatibility of HDPE/CaCO3/EOC composites were studied in this research. The results showed that the composites containing 20% loading of 60-nm CaCO3 particles without a surface treatment caused the particle agglomeration. Its poor dispersion in the polymer matrix lowered the Izod impact strength by 37.7% and yield strength by 2.3% but increased breaking strength and tensile modulus of the composites as compared to the neat HDPE. The surface pre-treatment of CaCO3 with the titanate coupling agent KR TTS or KR 12 decreased the CaCO3 particle agglomeration to give better particle dispersion as observed in the SEM micrographs. The KR TTS or KR 12 at 0.8% weight loading of CaCO3 increased the Izod impact strength by 29.6% and 31.4%, respectively, in comparison with the untreated composites. Tensile modulus was still lower than that of the neat HDPE but the yield strength was increased. The use of EOC markedly improved the Izod impact strength of the HDPE composites especially when the pre-treated CaCO3 particles with 0.8% weight of KR TTS or KR 12 was used in combination with EOC at 2% loading, a higher Izod impact strength when compared to the neat HDPE was obtained. When the polymer composite contains the untreated CaCO3, a 6% EOC loading must be incorporated to achieve the higher Izod impact strength as compared to the neat HDPE.
DOI: 10.14457/cu.the.2009.1605
title: Characterization of plasmid-mediated quinolone resistance genes in Salmonella isolates from patients and animals in Thailand

description: Nontyphoidal Salmonella is considered to be acquired from animals to human via food chain. Fluoroquinolones, drug of choice for Salmonella infection has become reduced susceptible and clinical failure has been reported. The chromosomal-mediated fluoroquinolone resistance mechanisms are commonly due to the drug target alterations in gyrA, gyrB, parC and parE genes which can cause high level of resistance. Other resistance mechanism is the presence of plasmid-mediated genes, including qnr genes and aac(6’)-Ib-cr genes which become more clinical concern because of the ability of horizontal gene transfer. This study characterized the plasmid-mediated quinolone resistance genes and investigated the prevalence of qnr genes and aac(6’)-Ib-cr genes in 356 nontyphoidal Salmonella isolated from 108 patients and 248 animals. Prevalence of nalidixic acid resistance in patient isolates was 86.1% and reduced susceptibility to ciprofloxacin was found in 72.2%. High rate of reduced susceptibility was found in S. Choleraesuis (30.56%). Prevalence of nalidixic acid resistance was 42.6%, ciprofloxacin resistance was 0.4% and reduced susceptibility to ciprofloxacin was found in 41.36%. Reduced susceptibility was mostly found in S. Enteritidis (8.06%, 20/248). Screening for the presence of qnr and aac(6’)-Ib-cr in 356 nontyphoidal Salmonella isolates showed that qnrS gene was found in 8.70% (31 isolates) and there was no isolate carrying aac(6’)-Ib-cr. The prevalence of qnrS genes in isolates from patients was 3.7% (4/108) which were found in S. Choleraesuis (1 isolate) and S. group D (3 isolates). The prevalence of qnrS genes in isolates from animals was 10.88% (27/248) and the most common serovar carrying qnr genes was S. Anatum (9 isolates). This study was the first report of the prevalence of qnrS in nontyphoidal Salmonella isolated from Thailand. DNA sequencing analysis of the qnrS gene of all 31 qnrS-positive revealed 100% nucleotide and amino acid identity to qnrS1 and QnrS1 submitted in GenBank. The in vitro selection of ciprofloxacin resistance demonstrated that 4 out of 5 qnrS1-positive parent strains raised ciprofloxacin MIC to 32-64 µg/ml in the third-generation selection whereas 2 out of 5 qnrS1-negative parent strains raised ciprofloxacin MIC to 32 µg/ml. Single amino acid substitutions in GyrA were found at S83F, Y and D87G when the ciprofloxacin MIC of mutants increased to &gt; 1 µg/ml. The double mutations at S83 and D87 in GyrA led to higher ciprofloxacin MIC. However, there was an increase in ciprofloxacin MIC without any mutation in GyrA, suggesting that there were other mechanisms involved in the development of resistance such as mutations in QRDR of ParC, overexpression of efflux system and decreased outer membrane porins.
DOI: 10.14457/cu.the.2009.1606
title: Anti-inflammatory activity of Harrisonia Perforate root extract

description: Inflammation is a beneficial host response to pathogen or tissue injury. It stimulates immune cells to release a variety of inflammatory mediators and cytokines such as tumor necrosis factor-a (TNF-a), interleukin-1b (IL-1b), interleukin-6 (IL-6), prostaglandinE2 (PGE2) and nitric oxide (NO). Harrisonia perforata Merr. (Simaroubaceae) root is one of the five root compositions of a Thai traditional medicine named Bencha-Loga-Wichien which is used as a remedy for treating fever. In this study we investigated the potential anti-inflammatory property of the ethanolic extract from H. perforata root on LPS-activated macrophage,J774A.1 cells and in carrageenan-induced rat paw edema model. H. perforata significantly inhibited various pro-inflammatory cytokines expression. The inhibitory concentrations were observed at 12.5 - 50 µg/ml in concentration-dependent manner. The maximum inhibitory effects of H. perforata extract (50 µg/ml) were 49.83% and 47.27% for TNF-a and IL-1b respectively. For IL-6, the mamximum inhibitory effect (32.16%) was shown at concentration 12.5 µg/ml. H. perforata extract 50 µg/ml also effectively decreased mRNA expression of important inflammatory enzyme iNOS and COX-2 level up to 88.11% and 93.68% respectively. There was no cytotoxicity at the highest concentration used in this study. Intraperitoneal treatment of rat with H. perforata (50, 100, 200 and 400 mg/kg) reduced the effect on acute inflammation induced by carrageenan in paw edema model by 28.49% , 31.18%, 47.85% and 65.05% respectively at 2 hour after stimulation. All the results obtained from this study indicated that H. perforata possessed anti-inflammatory action.
DOI: 10.14457/cu.the.2009.1607
title: Stability of Roselle, Lac and Gardenia colors in micellar systems

description: Natural colors were used in place of synthetic colors because of low toxicity. However, limitation of using natural colors is due to their stabilities. This research intends to study changes and stabilities of three natural water-soluble colors; i.e. roselle petal, lac stick, and gardenia fruit in 3 micellar systems; i.e. sodium dodecylsulphate or SDS (anionic surfactant), cetyltrimetylammonium bromide or CTAB (cationic surfactant), and Tween80 (non-ionic surfactant) at concentration of 1, 5, 10, and 15 folds of their CMC values. Physicochemical characteristics of the extracted dyes were evaluated using several techniques including visible spectroscopy, pKa determination, HPLC, and LC-MS. Preliminary stability under six conditions (water, temperature, acid, base, oxidation, and UV light) and color stability in micellar systems were monitored by spectroscopy technique in terms of color intensity, color density, and percentage of color remaining at various times and CIELab system. The maximum wavelengths (λmax) of roselle, lac, and gardenia colors were 528, 490, and 443 nm corresponding to visualized colors of red, orange, and yellow, respectively. The apparent pKa of roselle and lac dyes were 3.00 ± 0.08 and 5.96 ± 0.15, respectively. HPLC and LC-MS showed that roselle dye composed of delphinidin-3-sambubioside and cyanidin-3-sambubioside as major coloring. Lac dye was a mixtures of laccaic acid A, B, and C, while the major components of gardenia dye were crocin, crocetin monogentiobiosyl monoglucosyl ester, and crocetin monogentiobiosyl ester. Roselle dye was unstable in alkaline, at elevated temperature, under oxidation, and under UV light. Lac color was unstable in alkaline, under oxidation and under UV light, while gardenia color was unstable in all conditions. Stabilities of roselle and lac dyes in micellar systems were in an order of in buffer &gt; Tween80 micelles &gt; SDS micelles while the color stability of gardenia was in an order of in SDS micelles &gt; buffer &gt; Tween80 micelles. Evaluation of color and color changes using UV-visible spectroscopy and CIELab system gave consistent results to one another. Visible spectroscopy clearly shows interaction between dyes and micelles but cannot describe observed color in details. CIELab system is a better way in describing color quality but cannot demonstrate dye and micelle interactions.
DOI: 10.14457/cu.the.2009.1609
title: Preparation of pigmented inkjet ink for six-color printing on silk fabric

description: This research prepared five sets of pigmented inkjet inks and pretreated the silk fabric with chitosan, glycine and N-[(2-hydroxyl-3-trimethylammonium) propyl] chitosan chloride (HTACC) to enhance print quality. The six pigmented inkjet inks comprising black (Bk), cyan (C), magenta (M), yellow (Y), light cyan (LtC) and light magenta (LtM) colors were prepared with surface-modified pigments and a pigment-to-binder ratio of 1:2. The binder was the copolymer of styrene-acrylic acid emulsion. Different ratios of diethylene glycol and glycerol for verifying the ink viscosity, surface tension with jettability were investigated. The prepared inks had pH in the range of 6.7-8.8, zeta-potential in the range from (-35) to (-50) mV, the pigment particle sizes in the range of 100-300 nm, surface tension in the range of 39 – 46 mN m-1. The black inks prepared by the pigment-to-binder ratios of 1:0, 1:0.5, 1:1, 1:1.5 and 1:2 exhibited both the Newtonian flow at low shear rates (21-142 s-1) and non-Newtonian flow at high shear rates (180-741 s-1). The ink formulation 5 with a pigment-to-binder ratio of 1:2 which was in the jettable range on a viscosity-surface tension criteria map had the viscosity in a range of 2.78 – 3.44 mPa s which jetted the printing pattern completely. The ink formulation 5 was thus best suited for printing with an Epson piezoelectric type inkjet printer. The silk fabric pretreated with chitosan, HTACC, and mixed chitosan and glycine was then each printed with the ink formulation 5. The printed silk fabrics were analyzed for color gamut and color saturation, stiffness, light and wash fastnesses. The printed silk fabrics exhibited that the color gamut and color saturation of the pretreated fabrics provided a wider color gamut than the printed colors on the untreated fabrics. The mixed chitosan and glycine, and HTACC pretreatments enhanced markedly the chroma while the color strength of the fabrics with HTACC pretreatments increased most. The pretreated silk fabrics by chitosan or HTACC did not increase the fabrics stiffness. The light fastness of the pretreated fabrics did not change from the untreated ones, although the wash fastness increased from 4 to 4-5. The extent of coagulation efficiency between the pretreatment reagents and inks was investigated by UV-visible spectroscopy from which HTACC can exhibit strong interaction with the pigments in the inks.
DOI: 10.14457/cu.the.2009.1610
title: Mechanism of liposomes in the delivery of the P-glycoprotein substrate model calcein AM into Caco-2 cells

description: The aim of this present study was to investigate the probable mechanisms by which liposomes enhance delivery of P-glycoprotein (P-gp) substrates into Caco-2 cells. The effect of liposomal formulation factors (inclusion of charged lipids, cholesterol content, and type of phosphatidylcholine) was also determined. Calcein AM was used as a model molecule for P-gp substrates. Calcein AM-loaded liposomes were prepared by the film-hydration method followed by extrusion through 100 nm polycarbonate membranes. The possible mechanisms of calcein AM uptake from liposomes were investigated by several techniques. To identify the effect of liposomal formulation factors, the extents of calcein AM uptake into Caco-2 cells were compared among liposomes with different compositions. The result demonstrated that neutral liposomes (phosphatidylcholine:cholesterol at 7:3 molar ratio) could enhance the delivery of calcein AM into Caco-2 cells in a time- and concentration-dependent manner. The results from confocal laser scanning microscopy and fluorescence dequenching technique studies substantiated endocytosis of calcein AM-loaded liposomes into Caco-2 cells. This mechanism was also supported by the inhibitory effect of endocytosis/metabolic inhibitors and the effect of temperature. On the contrary, the enhancement in calcein AM uptake via either the changing in cell membrane permeability or the modulation of P-gp function by liposomes was not evident. Charged lipids and type of phosphatidylcholine showed a strong influence on calcein AM uptake from liposomes. Calcein AM from both neutral and negatively charged (phosphatidylcholine: cholesterol:dicetyl phosphate at 6:3:1 molar ratio) liposomes was taken up by Caco-2 cells similarly and more efficiently than that from calcein AM solution. Positively charged (phosphatidylcholine: cholesterol:stearylamine at 6:3:1 molar ratio) liposomes failed to enhance calcein AM uptake into Caco-2 cells. Soybean phosphatidylcholine liposomes, either with or without cholesterol, could increase cellular uptake of calcein AM better than dipalmitoyl phosphatidylcholine liposomes did. On the other hand, cholesterol content inserted only a minimal effect on calcein AM uptake. The presence of 20-40 mole% of cholesterol in liposomes significantly reduced calcein AM uptake into Caco-2 cells, but with much less magnitude than the effects seen with the inclusion of charged lipids and the type of phosphatidylcholine. Overall results indicate that endocytosis was the main mechanism by which liposomes enhanced the uptake of calcein AM into Caco-2 cells. The liposomal composition also played a significant role in the delivery of the P-gp substrate calcein AM into Caco-2 cells.