cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.14457/cu.the.2009.1622
title: Synthesis, characterization and polymerization of 3,4-ethylenedioxythiophens substituted at ethylene bridge

description: Various routes to synthesis of EDOT substituted at ethylene bridge and other related derivatives have been attempted. Synthesis of new diethyl 3,4-dialkoxythiophene-2,5-dicarboxylate derivatives using double Williamson etherifications of the corresponding alkyl halides yielded the desired thiophene dicarboxylate precursors in range of yields. Decarboxylation obtained a new potential monomer (Vinyl-EDOT). Halogenation of various thiophene derivatives with N-bromosuccinimide (NBS) or N-chlorosuccinimide (NCS) have been accomplished in excellent yields (80-99%). Transetherification of 3,4-dimethoxy- thiophene with trans-1,2-cyclohexanediol to obtain 3,4-cyclohexylenedioxy- thiophene (CDOT) in good yield (86%). This monomer was subjected to oxidative polymerization to give poly(3,4-cyclohexylenedioxythiophene) (PCDOT) in 69%. 2,5-Dibromo-3,4-cyclohexylenedioxythiophene (DBCDOT) could be polymerized in solid state which also gave the polymer PCDOT. Characterizations of the resulting polymer were performed by NMR, FT-IR, SEM, UV-Vis, XRD, MALDI-TOF MS, TGA, DSC and Four-point-probe conductometer. Solid-state polymerized PCDOT heated at 120 ºC for 24 hours and stored at room temperature for 14 days gave the best value of conductivity up to 131 S/cm.
DOI: 10.14457/cu.the.2009.1623
title: Poly(dimethylsiloxane) microchip for detection of cholesterol

description: In this work, the rapid detection of cholesterol using poly(dimethylsiloxane) microchip capillary electrophoresis, based on the coupling of enzymatic assays and electrochemical detection, was developed. Direct amperometric detection for poly(dimethylsiloxane) (PDMS) microchip capillary electrophoresis was successfully applied to quantify cholesterol levels. Factors influencing the performance of the method (such as the concentration and pH value of buffer electrolyte, concentration of cholesterol oxidase enzyme, separation voltage, injection time, and detection potential) were carefully investigated and optimized. The migration time of hydrogen peroxide, product of the reaction, was less than 100 s when using 40 mM phosphate buffer at pH 7.0 as the running buffer, a concentration of 0.68 U.mL-1 of the cholesterol oxidase enzyme, a separation voltage of +1600 V, an injection time of 20 s, and a detection potential of +0.5 V. PDMS microchip capillary electrophoresis showed linearity between 38.7
DOI: 10.14457/cu.the.2009.1624
title: Improvement of Mycoepoxydiene production by Endophytic fungus Phomopsis sp. Hants25 isolate from Hydnocarpus anthelminthicus

description: Mycoepoxydiene exhibited broad spectrum of cytotoxicity against human tumor cell lines. According to the interesting cytotoxic activities of this compound, its mechanism of action and related studies should be pursued, and these experiments require a large amount of mycoepoxydiene. This study aims to improve mycoepoxydiene yield by varying fermentation conditions of Phomopsis sp. Hant25, an endophytic fungus isolated from Hydnocarpus anthelminthicus. Agar diffusion assay to determine relative amounts of mycoepoxydiene produced by different fermentation conditions was developed. Mycoepoxydiene was found to be clearly active against Candida albicans when tested in medium containing 12.5 µg/mL of ketoconazole. Several fermentation conditions were conducted. Culture media affected mycoepoxydiene production by the fungus. Mycoepoxydiene obtained from conventional shaken and stationary liquid fermentations were low. Analysis by HPLC revealed that mycoepoxydiene amount was increased approximately 13.56 times yielding 333 mg/L when cultured in MM1D medium with filter support at 25°C under static condition for 6 days and then agitation at 120 rpm for 12 days. Fungal morphology in culture medium during fermentation was found to be related to mycoepoxydiene yield.
DOI: 10.14457/cu.the.2009.1626
title: Protective effects of captopril on oxidative strees-induced disruption of tight junction structure and function in ECV304 cells

description: The objective of this study was to investigate the protective effects of captopril on oxidative stress-induced hyperpermeability of epithelial barriers, using the in vitro model of ECV304 cell monolayers grown for either 2 days or 12 days after seeding. Treatment the monolayers with H2O2 (200 µM for 4 h) had no effects on cell viability as measured by MTT assay. In 12 days after seeding, the ECV304 monolayers developed high transepithelial electrical resistance (TEER) value and restrictiveness against paracellular movement of phenol red, suggesting the formation of tight junction complexes. Exposure to H2O2 resulted in reduction of TEER and phenol red hyperpermeability. In addition, immunofluorescence visualization indicated the disruptive pattern of occludin and ZO-1 at the cell borders. However, the amount of occludin and ZO-1 proteins remained normal with the western blot analysis. In 2 days after seeding, the barrier function of ECV304 was not fully developed. Treatment of H2O2 during this period caused disruptive pattern of immunofluorescence staining of occludin and ZO-1 along with the decreased amount of occludin protein. Pretreatment the monolayers with captopril (100 µM for 30 min) prior to H2O2 could preserve the barrier restrictive functions. Regardless of the period, captopril was able to abolish the oxidative damages on localization and amount of tight junction proteins. The results also suggested the involvement of ERK1/2 pathway in tight junction stability.
DOI: 10.14457/cu.the.2009.1627
title: Spinning and properties of isotactic polypropylene/hydrophobic silica nanocomposite fibers

description: Silica particles filled polypropylene filament fibers were prepared. Firstly, melt mixing and solution (toluene) mixing were carried out to predisperse silica agglomerates, leading to composite resins. Then, the obtained composite resins were spun into multifilament fibers with various spinning speeds using the Fourne’s pilot plant fiber spinning machine (for melt mixed masterbatches) and free-fall monofilaments using ThermoHaake’s single screw extruder (for solution mixed resins). The characterizations of spun composite fibers including morphological analyses (SEM and AFM), crystallization temperature (DSC) and the fine structure (XRD) were studied. Properties evaluation included thermal property (TGA), tensile strength, shrinkage and surface hydrophobicity by contact angle measurement. SEM images of multifilament fibers demonstrated that shear stress applied during melt-mixing failed to overcome cohesion force among agglomerate particles. Successfully, AFM images revealed that solution mixing via autoclave treatment could disaggregate the silica agglomerates into nanoscale particles, producing an even distribution of nanoparticles within the bulk of the fiber or on the surface. As a consequence, the presence of the nanoparticles favorably induced heterogeneous nucleation process in the free-fall filament as evidenced by DSC analysis. Hot stage images further confirmed the nucleating effect of silica nanofiller. Well dispersion of nanoparticles in PP matrix resulted in an improvement in shrinkage properties of nanocomposite fibers. Furthermore, the surface hydrophobicity of the nanocomposite fibers was found higher than neat fiber thanks to an increase in surface roughness arising from the presence of nanoparticles on the surface.
DOI: 10.14457/cu.the.2009.1628
title: Synthesis of polyacrylamide/mica superabsorbent nanocomposites with thermal stability and fire retardancy

description: Superabsorbent polymers of poly[acrylamide-co-(2-acrylamido-2-methylpropane sulfonic acid sodium salt)], poly(AM-co-AMPS-Na+), poly[acrylamide-co-(2-acrylamido-2-methylpropane sulfonic acid), poly(AM-co-AMPS-H+)] and poly(AM-co-AMPS-Na+) superabsorbent nanocomposites were synthesized by free-radical crosslinking polymerization. Ammonium persulfate (APS), N, N, N’, N’-tetramethylethylenediamine (TEMED), and N, N’-methylenebisacrylamide (MBA) were used as an initiator, a co-initiator, and a crosslinker, respectively. The superabsorbent nanocomposites were produced by adding mica, zinc borate or melamine as fire retardant agents. The influences of ionic comonomer (both the sodium and acid forms) and crosslinker concentrations on the water absorbency of the prepared superabsorbents were investigated. The presence of main function groups of the synthesized copolymers was analyzed using FTIR technique. The thermal stability of superabsorbent nanocomposites was detected by TGA and cone calorimetric technique. The equilibrium water absorbency of poly(AM-co-AMPS-Na+) and poly(AM-co-AMPS-H+) was found to increase with the increase in ionic comonomer concentration, and decrease with the increase in the crosslinker and fire retardant agent loadings. The maximum water absorbency of 1212±54 g g-1 was obtained for poly(AM-co-AMPS-Na+) at 85% mol of AMPS-Na+, 0.6% mol each of APS and TEMED, and 0.05% mol of MBA. The superabsorbent nanocomposite/20% zinc borate/10% melamine coated on a wood board increased the ignition time to 258 s from only 13 s ignition time of the uncoated wood.
DOI: 10.14457/cu.the.2009.1629
title: The association between thiopurine S-methultransferase *3C polymorphism and azathioprine induced myslosuppression in Thai patients with rheumatologic diseases

description: Rheumatic diseases are of unknown pathogenic origin; during of the molecular and cellular processes that lead to disease pathology. Drugs used of treatment include azathioprine as immunosuppressants. Thiopurine S-methyltransferase (TPMT) is an enzyme important in drug metabolism which located in cytoplasm and genetic variation. Patients inheriting TPMT deficiency is at high risk of myelosuppression. The aim of this study was to characterize the TPMT*3C polymorphism. TPMT genotypes were determined using PCR-RFLP assays and TPMT activity RBC using HPLC method in 112 Rheumatogic patients taking azathioprine treatment. Biochemical and clinical data were retrospective. The results of genotyping analysis that found eight patients (7.14%) were heterozygous (TPMT*1/*3C) and one-hundred and four patients (92.86%) were homozygous TPMT*1 (A/A). The allele frequencies were 3.57% for “G” allele and 96.43% for “A” allele. The result show TPMT*1/*3C polymorphism are statistic significantly different (P &lt; 0.001) and odd ratio 26.0, 95%CI 4.783 – 141.333 higher risk for AZA-induced leucopenia. Both patients groups taking azathioprine dose between 0.65 – 2.50 mg/kg/day that mean 1.54 ± 0.51 (SD) between azathioprine dose that result show not significantly different (P = 0.186). But not significantly different induced neutropenia (P = 0.06, odd ratio 8.889, 95%CI 1.237 – 63.878) and lymphopenia (P = 0.085, odd ratio 6.583, 95%CI 0.995 – 43.553). The mean of TPMT activity between TPMT*1/*1 (37.90 ± 12.64) and TPMT*1/*3C genotypes (17.53 ± 4.96) that found both groups were significantly difference (P&lt;0.001). Base on the enzyme activity in RBCs which the optimal cut-off activities for TPMT activity calculated intermediate activity was ≤ 23.01 nmol 6-MTG/gHb/hr and high activity was &gt; 23.01 nmol 6-MTG/gHb/hr with AUC. The statistical represent association between leucopenia (P = 0.003, odd ratio 21.5, 95%CI 2.961 – 156.128). But not significantly different induced T neutropenia (P = 0.059, odd ratio 11.25, 95%CI 1.233 – 102.623) and lymphopenia (P = 0.391, odd ratio 2.933, 95%CI 0.254 – 33.823) same as compared with genotype.
DOI: 10.14457/cu.the.2009.1630
title: Preparation of 4-carboxybenzenesulfonamide modified chitosan for delivery of acetazolamide

description: The objective of this research is to modify chitosan (CS) with various ratio of 4-carboxybenzensulfonamide (4-CBS) to improve a mucoadhesive property and thus increases the chance of carbonic anhydrase inhibitor being delivered through the mucosa of the stomach for eradication of H. pylori. The 4-CBS-CSs were characterized by 1H-NMR, FT-IR spectroscopy, DSC and TGA analysis. The 4-CBS-CS (1:0.05) has mucoadhesive property and swelling ratio better than CS, and can tolerate in the stomach condition for at least 24 hours in the simulated gastric fluid (pH 1.2) and the phosphate buffer (pH 5.5). The 4-CBS-CSs were non-toxic to Vero cell and inactive against anti-cancer cell lines of epidermoid carcinoma of oral cavity (KB), breast adenocarcinoma (MCF-7) and small cell lung carcinoma (NCI-H187). Moreover, the 4-CBS-CSs can inhibit Escherichia coli (E.coli) and Staphylococcus aureus (S.aureus) better than CS. The application of 4-CBS-CS is focused on the immobilization of acetozalamide (ACZ) onto CS and the 1:0.05 4-CBS-CS in the form of microspheres by electrospray technique. The particle sizes were in the range of 2-8
DOI: 10.14457/cu.the.2009.1631
title: Preparation of activated carbon from petrochemical waste sludge by chemical and physical activation

description: The research was the study of the effect of activation by petrochemical waste sludge by physical activation with superheated steam carbondioxide and chemical activation by suitable chemical with potassium hydroxide, phosphoric acid and zinc chloride on properties of activated carbon from sewage sludge. The experiment work included two steps. The first step was carbonization which was carried out in the temperature range of 375-450 ºC. It was found that the optimum condition was 400ºC for 90 min. The second step was activation by chemicals and physical activations. The study variables were temperature, time, and, char particle size form waste sludge. The optimum activation condition was chemical activation by zinc chloride; size 1.18-2.36 mm.at temperature 350 ºC 1 hour and flow rate of nitrogen of 250 ml/ min. The property of prepared activated carbon from waste sludge was % yield of 88.53, bulk density of 0.35 g/cm2, iodine number of 648.50 mg/g, methylene blue number of 296.13 mg/g, B.E.T. surface area of 551.23 m2/g.The prepared activated carbon from waste sludge from petrochemical could be the commercial grade, because the accepted standard iodine absorption is more than 600 mg/g.
DOI: 10.14457/cu.the.2009.1632
title: Synthesis and optical properties of porphyrins with exocyclic aromatic rings

description: A series of meso-aryl substituted porphyrin with fused phenanthrene subunits have been synthesized to obtain insights into the influence of conjugated porphyrin systems on the electronic properties. Barton-Zard condensation of 9-nitro-phenanthrene with ethyl isocyano-acetate afforded phenanthro[9,10-c]pyrrole-1-carboxylate in good yield. Cleavage of the ester moiety with KOH in refluxing ethylene glycol gave phenanthro[9,10-c]pyrrole as a precursor of porphyrins. meso-Tetraaryltetraphenanthroporphyrin can be obtained using Lindsey condensation of phenanthro[9,10-c]pyrrole with aryl aldehyde at low temperature using boron trifluoride as catalyst. These compounds were characterized by 1H-NMR, and UV-visible spectroscopies, and MALDI-TOF mass spectrometry. The UV-visible spectra of highly conjugated porphyrins showed that ring fusion had a profound impact on the producing bathochromic shift of the Soret and Q bands into the near-infrared region. Absorption in this area is useful for wide applications in many fields including biomedicine and materials.
DOI: 10.14457/cu.the.2009.1633
title: Determination of DNA sequences using peptide nucleic acid in combination with chitosan particles by maldi-top mass spectrometry

description: Determination of DNA sequences is significantly important for many biotechnology-related applications ranging from medical, forensic, agriculture, and food science. The concept of using a new conformationally constrained pyrrolidinyl peptide nucleic acid (acpcPNA), anion-exchange captures in combination with MALDI-TOF mass spectrometry has been recently proven as a simple and effective way for DNA sequence analysis. This research has introduced chitosan quaternized chitosan particles as anion-exchange captures that may be applicable for the same purpose. The particles were prepared by either homogeneous or heterogeneous quaternization. The success of sub-micron, spherical, and positively charged quaternized chitosan particle formation was verified by FT-IR, 1H NMR, PCS, and TEM analyses. Investigation by MALDI-TOF mass spectrometry suggested that some quaternized particles in combination with acpcPNA were capable of detecting a single mismatched base out of 9-14 base DNA sequences. The success of selective detection generally required rinsing of the particles after capturing PNADNA hybrid by 20% formamide in phosphate buffer solution. Potential application of this technique for a synthetic DNA of which sequence mimics mutant K-ras DNA, a mutated region that is associated with cancer has also been demonstrated.
DOI: 10.14457/cu.the.2009.1634
title: Nanospheres from UV-absorbing chitosan derivatives

description: In this work, four groups of UV-absorbing chitosan derivatives were synthesized. They include 1) UVB filter cinnamoylchitosan (CC) 2) UVA filter 2,4,5-trimethoxycinnamoylchitosan (245CC) 3) UVA filter 4-hydroxy-3-methoxycina malidene succinylchitosan (43CSC) and 4) UVB filter 2,4-dimethoxybenzalidenesuc cinylchitosan (24BSC). Fabrication of nanoparticles from the obtained derivatives was carried out by solvent displacement method. It was found that the size of the particles varied with degree of cinnamoyl substitution. 2,4,5-Trimethoxycinnamoyl chitosan and 2,4-dimethoxybenza lidenesuccinylchitosan are more photostable than cinnamoylchitosan and 4-hydroxy-3-methoxycinnamalidenesuccinylchitosan, respectively. In addition, 2,4-dimethoxybenzalidenesuccinylchitosan possess similar UVB filtering efficiency to the popularly used UVB filter 2-ethylhexyl-4- methoxycinnamate.
DOI: 10.14457/cu.the.2009.1635
title: On-line solid phase extraction coupled with sequential injection system for determination of sulfonamides

description: In this work, sequential-injection on-line solid-phase extraction (SPE) coupled with high-performance liquid chromatography (HPLC) for the separation and determination of sulfonamides (SAs) has been developed. A homemade microcolumn SPE was automated by sequential-injection analysis to perform on-line sample clean-up and extraction. A sequential-injection analysis (SIA) system consisting of a syringe pump and multi-position valve was constructed. This method can continuously extract sulfonamides from aqueous samples followed by the separation of sulfonamides using HPLC coupled with boron-doped diamond (BDD) electrode as electrochemical detection. The conditions for on-line SPE including eluent, flow rate of sample loading and elution, and zone of eluate were investigated. An eluent composition of methanol was selected. The optimal flow rate of sample loading and elution was found to be 10 µL/s and optimal elution time was 20-24 s. Under optimal conditions, a linear relationship between peak height and sulfonamides concentration was obtained in the range of 0.01-8 ppm. The results demonstrate that this method is simple, rapid and highly sensitive for the automated extraction, separation, and determination of sulfonamides.
DOI: 10.14457/cu.the.2009.1636
title: Industrial management system comparative analysis for sugar industry in Thailand and Myanmar

description: The objective of this project is to develop an understanding of the most functional and competitive means of analysis of business structure for sugar industry in Thailand and Myanmar in ways that will maximise benefits to the organisation. The paper focuses on the issues involve in the successful preparation of sugar industry. The methods used in the project development include a preliminary understanding of sugar industry; their advantages and disadvantages; the collection of information and interviews of the qualified authorities; the experiment of the problem using depth interview; and the analysis of the results and the answer to the main project’s questions on the system comparative analysis for sugar industry. It is found in this research that there are many main subjects in determining a competitive sugar industry in a context of competitive management system, which include process planning, price of raw material, transportation cost, improving line design, tax system, and space requirement for sugarcane farming. In addition, the example of ideal case for sugarcane factory and sugarcane farming that are suitable for the industry is presented in the paper. The expected significance of the project is the understanding of the most effective criteria of investing and improving a competitive sugar industry. In the long run, Myanmar is still be competitive for investing in the sugar industry for domestic consumption and especially for export, because of land availability, cheap price, low wages for the laborers and there is enough water supply as the rainfall is 40-80 inches rain in sugarcane areas and moreover, the infrastructure will improve in the future.
DOI: 10.14457/cu.the.2009.1637
title: Manufacturing cost reduction in textile factory

description: The objective of this thesis is to study and analyze the current problems happened in the textile factory in order to find the methods to reduce the production costs by applying the principle of engineering industry such as work study, document management system, analysis of industry costs’ structure and cost estimation including apply the computer software to help for calculating the production cost. As the results of study, the main problems of the sample factory are the inefficiency of document management system, the inappropriate costing system, and the loss in the production process. Thus, the researcher propose the methods in order to solve the problems as follows: 1.Improve the document management system within the sample factory 2.Apply “Cause and Effect diagram” to analyze the root causes of problems in order to find the efficient solutions. 3.Apply the work study method to set the standard work method, the standard time, and reduce losses in the production process. 4.Apply the computer program (Microsoft Office Access) to calculate the production costs. As the results of improvement, it found that the percentage of defect and waste decreased around 30.69%, the rate of direct labor cost per direct labor hour decreased around 7.42%, and the performance of workers increased around 6.31%. Furthermore, the accuracy of database has been improved that will help the top manager to decide to work more efficient and faster.