cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.14457/cu.the.2007.1806
title: Structures and properties of strontium ion doped Ln(Pr, La)₂(Co, Ni, Cu)O₄ perovskites

description: The perovskite–like oxides Ln(Pr, La)₂₋ₓSrₓMO₄ (M = Co, Ni, Cu) (x = 0.4, 0.6, 0.8, 1) were synthesized by the modified citrate method in order to study the influence of strontium doping at A–site on the structure and property. As the results, characterized by XRD supported by FT–IR and SEM, all specimens can be prepared and showed homogeneous K₂NiF₄–phase but Ln(Pr, La) ₂₋ₓSrxCoO₄ series had physical instability. The substitution of Sr²⁺ (larger radius) for Pr³⁺ or La³⁺ (smaller radius), caused the transformation of structure from orthorhombic to tetragonal. Moreover, doping with strontium affected on the decreasing of melting points of the materials, resulting in enhanced grain growth according to the density. However, Cu also can affect the decreasing of the melting point of Ln(Pr, La) ₂₋ₓSrₓCuO₄, so the fusion of grain of cuprates more easily occurred than that of nickelates. The electrical conductivity can be improved by addition Sr at A–site. The conductivities of the nickelate were higher than that of cuprate. PrSrNiO4 showed the highest electrical conductivity (423.5 S/cm at 300 ℃) which was about 4 times higher than that of undoped Pr₂NiO₄ (107.4 S/cm at 400 ℃) and LaSrNiO₄ showed the electrical conductivity of 361.6 S/cm at 400 ℃ which was about 4.5 times higher than that of La₂NiO₄ (80.1 S/cm at 400 ℃). The higher electrical conductivity of PrSrNiO₄ combined with higher oxygen adsorption indicate that this material could be a good candidate for use in solid oxide fuel cell.
DOI: 10.14457/cu.the.2007.1807
title: Performance improvement of solid oxide fuel cell system fed by methane

description: The research focuses on the improvement of methane-fuelled solid oxide fuel cell system. Three improvements of the system were considered: 1) Operating under a non-uniform potential operation (SOFC-NUP), 2) Implementing a membrane reactor to the SOFC system (SOFC-MR) and 3) Integrating a CaO-CO₂ acceptor with the SOFC system (SOFC-CaO). For SOFC-NUP, the optimum split ratios of Sp,1 = 0.55 and Sp,2 = 0.45 was found to improve power density as high as 9.2%. In addition, the increase in the number of separated section (n) of the cell could increase the achieved maximum power density but less pronounced after n &gt; 3. For SOFC-MR, an SOFC system integrated with a palladium membrane reactor operating at different modes; i.e., high pressure compressor (MR-HPC), vacuum pump (MR-V) and combined high pressure compressor and vacuum pump (MR-HPC-V) was considered. The power density of the SOFC was improved, depending on the increasing hydrogen recovery (). At high electrical efficiency, the SOFC-MR system became more attractive than the conventional system. It was found that the MR-HPC-V was the best operation mode among MR-SOFC systems. For the CaO-CO₂ acceptor SOFC systems, the CO₂ capture efficiency (Ec) depends on fresh feed CaO (F0), recycled CaO (FR) and amount of CO₂ ¬fed through. The CaO-CO₂ SOFC systems (i.e. CaO-After-Burner, CaO-After-SOFC and CaO-Before-SOFC) were compared with the conventional SOFC. Only CaO-Before-SOFC can improve SOFC performance which depends on both CO2 capture efficiency (Ec) and fuel utilization (Uf). The CaO-SOFC system can operate at lower cost than the conventional SOFC. The total added cost/reduced CO2 ($.mol-1) are in the sequence of the CaO-After-Burner &gt; CaO-After-SOFC &gt; CaO-Before-SOFC. Unfortunately, CaO-Before-SOFC can not reduce CO2 more than 40%. When the CO₂ reduction was required more than 40%, the CaO-After-SOFC was a suitable choice for the SOFC-CaO system.
DOI: 10.5281/zenodo.3345822
title: Cytokines in malaria patient

description: this demographic data and result of cytokines to malaria patient in East Nile locality, Khartoum Sudan
DOI: 10.5281/zenodo.3345823
title: Cytokines in malaria patient

description: this demographic data and result of cytokines to malaria patient in East Nile locality, Khartoum Sudan
DOI: 10.14457/cu.the.2007.1808
title: DNA fingerprint analysis of Rauvolfia in Thailand

description: Rauvolfia is a medicinal genus belonging to family Apocynaceae. There are five Rauvolfia species reported in Thailand: Rauvolfia serpentina, R. cambodiana, R. micrantha, R. sumatrana, and R. verticillata. Chemical constitution and biological activity in Rauvolfia species were studied and found that there are differences among them. Root of R. serpentina and R. cambodiana were reported as medicinal herbs in Thai herbal medicine. Root of R. serpentina has been used as antihypertensive, antipyretic, anthelmintic, sedative and palliative for insanity. Root of R. cambodiana has been used similar to R. serpentina, but it lacks of antihypertensive activity. Since R. cambodiana was reported as an adulterant for R. serpentina, the precise of authentication of R. serpentina is necessary for quality control of the use for antihypertensive purpose. The accurate identification and quality control of the plant material is, therefore, an essential prerequisite for ensuring the quality, safety, and efficacy. The goal of this study was fingerprinting the internal transcribed spacer (ITS) of rDNA of Rauvolfia species existing in Thailand. Phylogenetic relationship of them were analyzed. Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) method was applied as a molecular marker to discriminate Rauvolfia species in Thailand. Five crude drugs purchased from crude drug markets were identified in this study. Combination of ITS sequence and PCR-RFLP technique provide an effective and accurate identification of Rauvolfia species in Thailand.
DOI: 10.14457/cu.the.2007.1809
title: Modified natural rubber latex by graft copolymerization with methyl methacrylate or styrene and hydrogenation using OsHCI(CO)(O₂)(PCy₃)₂ as a catalyst

description: Graft copolymerization of methyl methacrylate or styrene onto natural rubber in latex form has been carried out using cumene hydroperoxide redox initiator. The synthesized graft copolymers were purified and then characterized by proton nuclear magnetic resonance. Grafting efficiency is discussed with respect to the influence of initiator concentration, monomer to rubber ratio and reaction temperature. The purified graft copolymer was then hydrogenated by using a homogeneous osmium complex catalyst, OsHCl(CO)(O₂)(PCy₃)₂. A detailed kinetic investigation of the hydrogenation was carried out by monitoring the amount of hydrogen consumption as a function of reaction time using a gas-uptake apparatus. The kinetic results for the hydrogenation of graft natural rubber indicated that the rate of hydrogenation exhibited a first -order dependence on the catalyst concentration and a first -order dependence on [C=C] for methyl methacrylate grafted natural rubber and a second-order dependence on [C=C] for styrene grafted natural rubber. Due to the presence of impurities within the natural rubber the rate of hydrogenation was found to decrease with increasing polymer concentration. The apparent activation energy for hydrogenation of natural rubber grafted with methyl methacrylate and natural rubber grafted with styrene was found to be 70.3 and 106.5 kJ/mol, respectively. The addition of a small amount of acid and PMMA or PS provided a beneficial effect on the hydrogenation of grafted natural rubber. The hydrogenated grafted natural rubber could be used as a compatibilizer for PMMA/EPDM or PS/EPDM blends. Thermal properties, mechanical properties and morphology of the blends were also investigated.
DOI: 10.14457/cu.the.2007.1811
title: Effects of recombinant anti-lipopolysaccharide factor isoform 3 protein on vibriosis prevention in the black tiger shrimp Penaeus Monodon

description: The broad spectrum of antimicrobial activity of the recombinant anti-lipopolysaccharide factor isoform 3 protein form Penaeus monodon (rALFPm3) was previously reported. Interestingly, the rALFPm3 is highly active against Vibrio harveyi, a shrimp pathogenic bacterium suggesting its potential use in control or prevention of the outbreak of Vibriosis in shrimp farming. Therefore, the rALFPm3 was produced in large scale in Pichia pastoris and purified by cation-exchange chromatography. The effects of extreme condition on anti-Vibrio activity of rALFPm3 were examined including salt, pH and temperature. The anti-Vibrio activity of rALFPm3 protein was reduced when the salt concentrations (1-3%) and pH (5-9) were increased. However, either incubation at various temperature (4, 30, 50 and 100oC) for 2 hours or storage at room temperature for three months did not effect the molecule integrity and its anti-Vibrio activity. We further investigated its activity in vivo in terms of neutralization and protective effect on V. harveyi challenged shrimp. At the concentration 6.25 µM, neutralization of V. harveyi (106 CFU) with rALFPm3 resulted in 100% shrimp survival. Protection of P. monodon from V. harveyi infection by pre-injected with rALFPm3 revealed a reduction of cumulative mortality from 60% to 25% comparing to the control shrimps. The effects of the rALFPm3 injection on expression levels of the representative immune genes, ALFPm3, PAP, PPA, SOD and survivin were examined in order to observe changes in shrimp immune response. The results indicated that rALFPm3 could affect several immune reactions including antimicrobial action, proPO system, antioxidant defence pathway and apoptosis but not affect the phagocytosis, Our results suggest the potential use of rALFPm3 in therapeutic and pharmaceutical applications in aquaculture.
DOI: 10.14457/cu.the.2007.1812
title: Iron regulates MMP-9 expression in oral squamous carcinoma cell lines

description: Head and neck squamous cell carcinoma (HNSCC) is a highly invasive cancer with distant metastasis and a cause of great morbidity and mortality worldwide. Over-expression of matrix metalloproteinase (MMP)-9 is implicated in the invasion and metastasis of HNSCC. There are increasing evidence of an association between iron overload and cancer progression. However, the effect of iron on MMP-9 expression in HNSCC has not been studied. In the present study, we examined the effect of iron on MMP-9 expression in HNSCC cell lines, OM-2 and HN-22. Ferric ammonium citrate (FAC), a source of iron, at 15 µg/ml increased MMP-9 expression in both cell lines in a dose dependent manner as shown by reverse transcription polymerase chain reaction and gelatin zymography analyses. Studies using specific inhibitors of extracellular signal-regulated kinase (ERK) 1/2 and Akt demonstrated that iron regulated MMP-9 through ERK1/2 and Akt, and ERK1/2 was an upstream activator of Akt. Analysis of electrophoretic mobility shift assay revealed that iron induced MMP-9 expression by activation of activated protein-1 (AP-1). Since, application of neutralizing antibody against transferrin receptor-1 could not abolish the stimulated MMP-9 expression, this result suggested that iron uptake was non-transferrin dependent. In conclusion, this study was the first to demonstrate that MMP-9 was up-regulated by iron in HNSCC cell lines. We suggest that iron may be one of several factors that cause an increase of MMP-9 which is necessary for the development and progression of HNSCC.
DOI: 10.14457/cu.the.2007.1813
title: Sequence variation and linkage disequilibrium in the GABA transporter-1 gene (SLC6A1) in five populations : implications for pharmacogenetics research

description: GABA transporter-1 (GAT-1; genetic locus SLC6A1) is emerging as a novel target for treatment of neuropsychiatric disorders. To understand how population differences might influence strategies for pharmacogenetic studies, we identified patterns of genetic variation and linkage disequilibrium (LD) in SLC6A1 in five populations representing three continental groups. We resequenced 12.4 kb of SLC6A1, including the promoters, exons and flanking intronic regions in African-American, Thai, Hmong, Finnish, and European-American subjects (total n=40). LD in SLC6A1 was examined by genotyping 16 SNPs in larger samples. Sixty-three variants were identified through resequencing. Common population-specific variants were found in African-Americans, including a novel 21-bp promoter region variable number tandem repeat (VNTR), but no such variants were found in any of the other populations studied. Low levels of LD and the absence of major LD blocks were characteristic of all five populations. African-Americans had the highest genetic diversity. European-Americans and Finns did not differ in genetic diversity or LD patterns. Although the Hmong had the highest level of LD, our results suggest that a strategy based on the use of tag SNPs would not translate to a major improvement in genotyping efficiency. In addition, we performed reporter assays using SLC6A1 promoter constructs containing the insertion or non-insertion variants or using a promoterless construct. The insertion variant showed significantly more activity than the non-insertion promoter variant in multiple cell lines. Gel shift assays determined that nuclear proteins interact with the insertion sequence. Owing to the low level of LD and presence of recombination hotspots, SLC6A1 may be an example of a problematic gene for association and haplotype tagging-based genetic studies. However, the 21-bp insertion polymorphism leads to a dramatic increase in SLC6A1 promoter activity based on in vitro experiment. This polymorphism may prove useful in predicting clinical response to pharmacological modulators of SLC6A1 as well as GABAergic function in individuals of African descent.
DOI: 10.14457/cu.the.2007.1814
title: Taxonomy of spiny eels (synbranchiformes: mastacembelidae) in Thailand

description: The present taxonomic study is the update revision of spiny eels (Synbranchiformes: Mastacemeblidae) found in Thailand. It is based on specimens deposited in local reference collections and newly collected specimens throughout Thailand during June 2006 to September 2007. It represents an attempt to alleviate difficulties with the species identification of individual specimens by providing a treatment of the nomenclature and taxonomy of all available local members. Two genera and twelve species, Macrognathus aculeatus, M. circumcinctus, M. maculatus, M. meklongensis, M. semiocellatus, M. siamensis, M. zebrinus, Mastacembelus alboguttatus, M. armatus, M. erythrotaenia, M. favus and M. tinwini were recognized. All of them are freshwater fish. However M. erythrotaenia can be found in both fresh and brackish waters. Upon this study, M. tinwini is a newly recorded species. The species identification of the family Mastacembelidae is based largely on configurations and the presence or absence of colour markings on body and fins and different numbers of spines, fin rays and vertebrae. The dichotomous keys to genera and to species are provided. The information about the scientific names, synonyms and citations, common names, local names, examined material, diagnosis, descriptions, distribution, habitats, frequency distribution of spines, fins and vertebrae and photographs are available. Morphometric and meristic dendograms using Hierarchical cluster analysis were constructed.
DOI: 10.14457/cu.the.2007.1815
title: Effects of Curcuma Comosa extracts on choline acetyltransferase and acetylcholinesterase in rat brain

description: Curcuma comosa Roxb., a plant in family Zingiberazeae, is one of the well-known medicinal plants in Thailand. Rhizome of this plant has been traditionally used for the treatment of various abnormal symptoms of uterus. Those medicinal purposes of C. comosa may be associated with its estrogenic-like effects reported by many studies. The objective of this study was to investigate effects of C. comosa hexane and ethanolic extracts on the activities of choline acetyltransferase (ChAT) and acetylcholinesterase (AChE) in rat brain. Forty five rats were randomly divided into 6 treatment groups. Rats were administered orally with 1 ml/kg/day of corn oil (control group); 250 and 500 mg/kg/day of C. comosa hexane extract (group 2, 3); 250 and 500 mg/kg/day of C. comosa ethanolic extract (group 4, 5) for 30 days. Each group comprised 8 rats. Estradiol valerate was given intramuscularly to 5 rats at a dose of 10 μg/kg/day for 7 days, serving as an estrogen reference group. At the end of the treatment, rats were anesthesized then cervical dislocated. Serum samples were determined for estradiol concentration. Brain was collected and dissected for cerebral cortex, basal forebrain and hippocampus. Each brain region homogenates was prepared for enzyme activity assay. The results showed that both dosages of C. comosa ethanolic extract caused an increase of ChAT activity in cerebral cortex and hippocampus but not in basal forebrain. C. comosa hexane and ethanolic extracts did not affect AChE activities in all three brain regions. Estradiol given at the dosage regimen in this study did not affect both ChAT and AChE activities. Even though an increase of serum estradiol level from C. comosa extracts was less than the estradiol group, both extracts caused a significant increase of serum estradiol level as compared to the control group. These findings demonstrated that C. comosa ethanolic extract potentially possessed a beneficial effect on cholinergic nervous system showing by an enhancement effect on the activity of ChAT, an enzyme responsible for brain acetylcholine synthesis.
DOI: 10.14457/cu.the.2007.1816
title: Preparation and morphology of polydiacetylene from self-assembly of diacetylene lipids

description: Self–assembly of polydiacetylenes derived from vesicles of 10,12-pentacosadiynoic acid (PCDA) and its amide derivatives were investigated by using dynamic light scattering (DLS), atomic force microscopy (AFM) and transmission electron microscopy (TEM). The condensation reaction of PCDA with 5 and 0.5 equivalents, ethylenediamine yielded the corresponding monoamide (AEPCDA) and diamide (EBPCDA). The purpose of this investigation was to find the optimum conditions by varying conditions such as pH, ionic strength (NaCl) and concentration of lipids in Milli Q water. The optimum pH for preparing the nanovesicles (&lt;200 nm) was pH 5-7 for poly(PCDA) and pH 3 for poly(AEPCDA). For ionic strength, there was no significant difference of effect of various NaCl concentration in poly(PCDA) and its amide derivatives, so the required NaCl concentration for biomembrane preparation would be in a range of 0.1 mM – 1 mM NaCl. The various conditions for poly(EBPCDA) were ineffective because the stable and closed pack structure of poly(EBPCDA) to the external perturbations was tolerant. The study of thermochromism properties were also investigated by colorimetric method using a temperature controlled UV-Vis spectrometer. Accordingly the results indicate that the particle size had a close relation to the transition temperature. In poly(PCDA) at initial pH 5-7 nanovesicles had lower transition temperature than others. In contrast, poly(AEPCDA) at pH 3 nanovesicle had higher transition temperature than other, probably due to the effect of charged at headgroup that was protonated or deprotonated in difference environment of each monomer. Moreover, the color transition of poly(EBPCDA) exhibited excellent reversibility at initial pH 5-7 while those of poly(PCDA) and poly(AEPCDA) were irreversible. Those optimum conditions would become the useful applicational source for biosensors and thermochromic devices.
DOI: 10.14457/cu.the.2007.1817
title: Synthesis of epicatechin glycosides via specific transglycosylation of cyclodextrin glycosyltransferase

description: Transglycosylation of catechins by partially purified cyclodextrin glycosyltransferase (CGTase) from Paenibacillus sp.RB01 was investigated. Three to four glucoside products were obtained by TLC analysis when used (+) catechin, (-) epicatechin, or (-) epigallocatechin gallate as acceptor and beta-cyclodextrin as glucosyl donor. The enzyme showed higher acceptor specificity towards epigallocatechin gallate whereas the same specificity for donor substrate (starch, beta-cyclodextrin, maltoheptaose) was demonstrated. When the occurred products in the reaction were analyzed by HPLC, the optimum condition for transglucosylation with epicatechin as an acceptor was: incubation of 80 U/ml CGTase with 1.0% (w/v) beta-CD and 0.5% (w/v) epicatechin in 10 mM acetate buffer, pH 6.0 at 50℃ for 24 hours. The 18.07 % of overall product yield was obtained. The amounts of each product at Rt 27, 30, 45, and 48 minutes were 1.44%, 3.39%, 4.18%, and 8.33%, respectively. During optimization of transglucosylation reaction, epimerization of epicatechin to catechin was observed at alkaline pH, high temperature and longer incubation time. Reaction products were then prepared in larger scale and were isolated using Sephadex LH-20 and C18-reversed phase HPLC column. The 5.6% yield of major product at Rt48 min was obtained. The structures of the two major glucoside products elucidated by MS and NMR techniques were epicatechin-3́ -O-α-D-glucopyranoside (for Rt48 min) and epicatechin-3́-O-α-D-diglucopyranoside (for Rt45 min). The water solubility of epicatechin, the monoglucoside and the diglucoside in water were 4.9, 95 and 2.0 mg/ml, respectively. While the browning resistance to UV irradiation of epicatechin monoglucoside was higher than epicatechin diglucoside and epicatechin. The antioxidant activity of the products was also determined by DPPH scavenging assay. It was found that the inhibitory concentrations at which the absorbance of DPPH was reduced by 50% (IC₅₀) of epicatechin, the monoglucoside and the diglucoside were 25, 36 and 46 µM, respectively.
DOI: 10.14457/cu.the.2007.1818
title: Failure cost reduction in Dioctyl Phthalate manufacturing process using Six Sigma approach

description: This objective of this research is to reduce the failure cost production in Dioctyl Phthalate (DOP) manufacturing process by using Six Sigma approach. Six Sigma approach consists of 5 phases which are Define phase, Measure phase, Analyse phase, Improve phase, and Control phase. In the Define phase, the problem of failure cost in DOP finished product and objective of the project were identified with the scope focusing on reducing failure cost regarding two types of defects: high colour and low resistivity. Then, in the Measure phase, process capabilities of DOP finished product were calculated the measurement system evaluation and verification were performed by calibration and Gage R&R method. After that, in the Analyse phase, the causes of the defects were identified by brainstorming and organized by the Cause-and-Effect diagram. Then, the causes of defects were prioritized by applying Failure Mode and Effects Analysis (FMEA). Then, in the Improve phase, Design of Experiment (DOE) was applied to determine significant causes that affect the quality of DOP finished product colour and low resistivity value. Then, optimum factor operating conditions were determined. After implementing the new operating conditions, control charts were used to monitor a process and to inform when to take corrective actions in the Control phase. The results of this research are that the process capability of colour parameter was improved from 0.92 to 1.48 and from 1.03 to 1.57 for resistivity value parameter. Thus, the failure cost of DOP reprocessing was reduced from 1,327, 368 baht quarterly in 2007 to 0 baht in the first quarter of 2008.