cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.14457/cu.the.2009.1776
title: Bioactive compounds from Derris malaccensis, Carissa carandas and Carissa spinarum

description: Phytochemical study of the roots of Derris malaccensis Prain. led to the isolation of a new rotenoid, namely, 6-oxo-dehydroelliptone, along with six known compounds, 12-deoxo-12α-acetoxyelliptone, 12a-hydroxyelliptone, tephrosin, dehydroelliptone, deguelin and elliptone. Chemical examination of the stems of Carissa carandas L. led to the isolation of two new compounds, namely, (6S,7R,8R)-7a-[(β-glucopyranosyl)oxy]lyoniresinol and carandoside, along with three known compounds. The known compounds are (6R,7S,8S)-7a-[(α-glucopyranosyl)oxy]lyoniresinol, (-)-carissanol and (-)-nortrachelogenin. From the stems of C. spinarum L., twelve known compounds were isolated, including (-)-carissanol, (-)-nortrachelogenin, scopoletin, (-)-carinol, (+)-cycloolivil, (+)-8-hydroxypinoresinol, (-)-olivil, (-)-secoisolariciresinol, (+)-pinoresinol, carissone, digitoxigenin 3-O-β-D-digitalopyranoside and evomonoside. The structures of all of these isolates were determined on the basis of spectroscopic evidence, including comparison of their UV, IR, MS and NMR properties with previously reported data. These isolated compounds were evaluated for their free radical scavenging, anti-herpes simplex virus (HSV-1 and HSV-2), antibacterial and cytotoxic activities. Ten lignans were found to posses moderate free radical scavenging activity whereas two compounds showed weak activity. Two compounds, tephrosin and elliptone, exhibited moderate activity against HSV-1 and HSV-2 in post-treatment and inactivation assays while evomonside showed moderate activity against both types of virus only in the inactivation method. In addition, no compounds showed antibacterial activity at the concentration 128 µg/mL. Interestingly, elliptone possessed cytotoxicity against cancerous cells A549 and MCF7 but showed no toxicity against WI-38 normal cells
DOI: 10.17632/jys6pdx3p3.1
title: Managing group work: impact of peer assessment on student engagement

description: This dataset is used for the paper titled: Managing group work: impact of peer assessment on student engagement. The paper investigates whether and how students’ involvement in peer assessment enhances their learning experience through better engagement. Using a simple regression model based on a sample of 268 first-year undergraduates in a UK university, this study explores how group dynamics manifest in a student peer assessment context, and how these impact on students learning experience and engagement. The findings indicate that students can take responsibility for becoming and remaining engaged in the learning process, which makes group work more manageable for both students and academic staff. The study contributes to the literature by focusing on the assessment of the entire learning journey within a group rather than the final output. In particular, the study shows the significant contributions of peer assessment in managing student engagement in modules and/or assessments for large cohorts.
DOI: 10.14457/cu.the.2009.1711
title: Development of osmotically controlled drug delivery system using crosslinked and non-crosslinked hard gelatin capsules

description: The aim of this study was to explore the release characteristics of an elementary osmotic pump capsule (OPC) by using a crosslinked and a noncrosslinked hard gelatin capsule shell. The influences of drug solubility, film thickness and orifice size on drug release from the system were examined. Diltiazem hydrochloride (freely water soluble drug) and propranolol hydrochloride (water soluble drug) were used as the model drugs. Sodium chloride was used as the osmotic agent. Crosslinked hard gelatin capsules were prepared by controlled exposure to formaldehyde vapours. The OPC was prepared by filling the capsule No. 1 with the mixture of the model drug (90 mg), lactose and sodium chloride. Core capsules were coated using hydroxypropyl methylcellulose as subcoating and cellulose acetate as the semipermeable membrane; then the coated capsule was drilled on the rounded end position. Drug release studies were conducted using water, different ionic strength and pH solutions with isotonicity as the dissolution media. Lag time of drug release from the OPC using the crosslinked capsule was longer than that the non-crosslinked capsule shell. Diltiazem hydrochloride OPC using the non-crosslinked and crosslinked capsules could prolong drug release about 9 hours and closed to zero-order drug release rate up to 80 % of drug release (R[superscript 2] &gt; 0.9). Propranolol hydrochloride OPC using a non-crosslinked capsule and a crosslinked capsule could prolong drug release about 9 and 12 hours, respectively. About 90 % of the drug was released as zero-order rate for propranolol hydrochloride OPC (R[superscript 2] &gt; 0.9). It was found that propranolol hydrochloride OPC using the crosslinked capsule shell provided less fluctuations of release rate at various time intervals than using the non-crosslinked capsule. But the characteristics of release rate at various time points of diltiazem hydrochloride OPC prepared using different types of capsule shell was apparently similar. This might be attributed to the higher water soluble property of diltiazem hydrochloride. Ionic strength of dissolution media had effect on drug release of OPC. But drug release of OPC was independent of pH of dissolution media.
DOI: 10.14457/cu.the.2009.1712
title: Investigation on controlling parameters on zonal gas production of multilayer system

description: This study is intended to investigate controlling parameters of rate allocation from multi-layer system. The study is concentrated on the condition that rate allocation is proportional to gas volume in each layer. The effects from rock properties and flow rate to the gas volume allocation are investigated. The twolayered gas reservoir is used for investigation under various cases and the five-layered system is used for test of validity of this study to more layers reservoir. From the study, rate allocation of multi-layered gas reservoir is proportional to gas volume ratio during the stabilized flow on the conditions that flow rate is less than flow capacity of reservoir. The rate allocation of multi-layered gas reservoir is also proportional to a product of gas volume, rate of change of reservoir pressure, and inverse of reservoir pressure of each layer for longer period (the whole pseudo-steady state period). However, during the stabilized flow (part of the pseudo-steady stage period) the ratio of rate of change of reservoir pressure and reservoir pressure of all layers are very close to each other and can be cancelled out. The rate allocation obey kh ratio during the early stage of flow when flow rate is close to flow capacity. The other controlling parameters are flow rate and permeability
DOI: 10.14457/cu.the.2009.1713
title: Effect of reservoir fluid composition on carbon dioxide injection in gas condensate reservoirs

description: Gas condensate reservoirs encounter a condensate blockage problem when the pressure around the wellbore falls below the dew point pressure. The amount of the liquid dropout depends on the composition of the reservoir fluid. If the percentage of liquid increases, it will restrict the production. Gas injection is the effective method to solve this problem and help increase recovery of the valuable condensate liquid. The objective of this study is to evaluate the effect of different reservoir fluid compositions on carbon dioxide injection in a gas condensate reservoir. Ten sets of reservoir compositions were selected. A compositional reservoir simulation was used to simulate the performance of carbon dioxide injection. The results show that composition of reservoir fluid has a significant effect on the optimum starting time for carbon dioxide injection. In order to maximize condensate recovery, the time to start carbon dioxide injection is the latest time that carbon dioxide injection can revaporize liquid dropout before carbon dioxide concentration reaches the limit. When the dew point pressure is high or maximum liquid dropout is low, the most optimum time of injection will be quite early. In the case that the initial reservoir pressure is equal to the dew point pressure, carbon dioxide injection rate has to be higher than the production rate in order to maximize condensate recovery. The higher injection rate will keep the reservoir pressure high. Thus, liquid dropout around the wellbore can be completely revaporized. However, if the injection rate is too high, early carbon dioxide breakthrough at the producer will cause an early abandonment of the production due to high carbon dioxide content in the produced gas. When the maximum liquid dropout is low, the most optimum injection rate will generally be high.
DOI: 10.14457/cu.the.2009.1714
title: A needs analysis of secondary school students learning English as a third language in private Islamic schools in changwat Narathiwat

description: In the three southernmost provinces of Thailand, the majority of people are Muslims who speak their own language called Melayu as their mother tongue. They speak Thai as their second language, and they learn English as a third language in school. The people who live in these provinces also have their own socio-demographic characteristics and cultures than make them different from people residing in other regions in the country. The objective of the present study was to explore the needs and the attitudes of secondary students who are learning English as a third language in private Islamic schools in Narathiwat Province. The study also aimed to explore the attitudes toward English language learning of teachers and parents of secondary students who are learning English as a third language in private Islamic schools in Narathiwat Province. The subjects of the study included 118 Mattayomsuksa 2 students, four teachers, and ten parents selected from the largest and smallest private Islamic schools situated in Muang District, Narathiwat Province. Data were collected by means of self-administered questionnaires, interviews, and observation. Data analysis consisted of quantitative measures of mean and standard deviation and a qualitative measure of content analysis. The findings of the study revealed that the students felt that they needed to develop language skills more, especially speaking and reading. They had positive attitudes toward learning English as a third language, and they wanted to study English with more varied teaching and learning materials in the classroom. In addition, the findings showed that teachers believed that students needed to focus more on developing their writing and reading skills, especially reading English books, whereas the parents thought that English was important for their children because they could use it to mainly further their studies in higher education and also used it in their daily life. Based on the findings of the study, it is recommended that teachers and administrators of private Islamic schools should revise their existing English curricula to better suit the students’ need and solve their perceived problems by providing English teaching and learning activities and materials that both are interesting and motivating so as to make teaching and learning English as a third language in private Islamic schools more effective and successful.
DOI: 10.14457/cu.the.2009.1715
title: Copolymerization of ethylene/1-olefin with spherical silica-supported metallocene catalyst

description: At present, the first consideration and largest volume of polymers in the plastics industry (Polyolefins) are mostly consisting of polyethylenes and polypropylenes, which are often used in any application because of their excellent cost/performance value. LLDPEs (Linear low-density polyethylenes), synthesized by the copolymerization of ethylene with α-olefin, is the great commercial significance in polyethylene series. Which the metallocene / methylaluminoxane catalyst system participate in production of LLDPEs provide the great among of advantage. But there are only a few major problems, such as difficulty in controlling polymer morphology, inability to be used homogeneous metallocene in slurry or gas-phase, and need very large amount of methylaluminoxane to achieve maximum of catalytic activity. So,the way to wipe out the few constraints is attaching the metallocene to the support without losing the performances of the homogeneous complex and activation step of metallocene. This research proposed the development of metallocene catalyst by spherical silica supports with different particle diameter such as submicron, 3, 5, and 10 µm. This study was divided into two parts, which difference in the impregnation method. In the first part, the polymerization reaction was performed using a supported zirconocene/MAO catalyst, which was prepared by in situ impregnation method. The higher outer surface area of supports apparently resulted in increased polymerization activity for SiO2 3 µm. The polymerization activity was also dramatically increased when comonomer was added. The second part was similar to the first, but catalyst precursors were prepared by ex situ impregnation method. The optimum particle size gave the better activity, but too strong interaction between MAO and support affected the negative result to the catalytic system. All copolymer were characterized by means of 13C NMR and DSC.
DOI: 10.14457/cu.the.2009.1716
title: Optimization of multilayered water flooding using intelligent injectors and producers

description: In many reservoirs, there are multiple sand layers separated by shale layers. Waterflooding is often applied to improve oil recovery. In many cases, the injectivity contrast between the major layer elements would result in poor sweep efficiency. This thesis objective is to study that how much intelligent water injection and intelligent production wells control would improve oil recovery from multi-layer reservoirs in comparison to recovery from a single intelligent injection scheme and a single intelligent production strategy. In this study, the reservoir consists of 3 layers pay zones separated by a shale layer is modeled. The multi-segment well model and choke model were selected to model both the producers and injectors. Then, waterflooding process simulations were performed to find the maximum oil production of each strategy. The simulation results indicate that using downhole flow control in both injector and producer well give a slightly higher oil recovery compared to recovery from a single intelligent injection and a single intelligent production if the permeability contrast is low. However, the approach significantly reduces the amount of water production. If the permeability contrast is high, utilization of downhole control valve can increase the oil recovery as much as 9.33%.
DOI: 10.14457/cu.the.2009.1717
title: The effect of the European Union's patients' rights in cross-border healthcare initiative on medical tourism in Thailand

description: To investigate the possible effect of the European Commission proposed directive on the application of patient’s rights in cross-border healthcare on the medical tourism of Thailand through the push and pull factors. Issued in July 2008, the Directive has three working areas: safety and quality, cross-border scheme and European cooperation. If implemented, the Directive would have a direct effect on the push factors that drives EU patients to receive healthcare outside of the community by allowing indirectly solving the problem of the system through allowing patients to receive care in another Member States. The pull factors of medical tourists to come to receive treatment in Thailand, on the other hand, will be affected by change in the responsiveness of the European medical tourists to the pull factors. Through the analysis of the push and pull factors, the effect of the Directive on the Thai industry will be determined. The findings of this thesis are that the Directive will have different impact on the push factors depended on the population group and the countries. Overall, the cross-border movement will be facilitated because of the scheme established and the European co-operation. Some patients will gain more confidence. However, the Directive does not solve the inherent problems of the system, which cause the push factors to be strong. The pull factors, on the other hand, remain largely unaffected. Only in the area of immediate availability that responds to the waiting time will be affected. Particularly, the number of patients from countries with this problem, which are Germany, Sweden and the UK, will partially decrease. The industry will remain overall strong as European medical tourists that come to Thailand come for both travel and treatment.
DOI: 10.14457/cu.the.2009.1777
title: Heterogeneous oxidation of cyclohexane and ethylbenzene by transition metal-incorporated catalysis

description: This study is to focus on the preparation of heterogeneous catalysts with high catalytic activities for oxidation of cyclohexane and ethylbenzene. Three classes of materials were studied: layered double hydroxides (LDHs) and their corresponding mixed metal oxides, polyoxometalates and metal incorporated xerogels. Transition metals chosen for the study are Co, Cu, Ni, Cr and Mn. The LDHs and mixed metal oxide catalysts were utilized for the oxidation of ethylbenzene with tert-butylhydroperoxide. The use of other oxidants such as hydrogen peroxide or air are also investigated. The Ni [subscript 4.8 ] Al and Cu [subscript1.0] Mg[subscript 2.9] Al oxide catalysts showed high activity with high acetophenone selectivity and they can be reused. Polyoxometalate catalysts possessing acid, alkali and alkyl ammonium cations were compared their activity towards oxidation of cyclohexane and ethylbenzene with hydrogen peroxide. The catalyst with alkyl ammonium showed the highest activity. Metal incorporated xerogel catalyst was appropriate to catalyze oxidation of cyclohexane in tert-butyl hydroperoxide as well as in air without any solvent. The activity order is Co &gt; Cu &gt; Mn &gt; Cr &gt; Ni. They showed no leaching into the reaction mixture
DOI: 10.14457/cu.the.2009.1779
title: Testing the psychometric properties of the Thai version of The Minnesota living with heart failure questionnaire

description: The purpose of this study was to test the psychometric properties of the Thai version of the Minnesota Living with Heart Failure Questionnaire (MLHFQ). The subjects of the psychometric properties testing were 180 outpatients with chronic heart failure from cardiology and general medicine clinic at Phramongkutklao hospital. The Thai version of the MLHFQ and the Short Form-36 Health Survey (SF-36) version 1 were administered at baseline and next follow-up visit. Practicality was assessed with average time of administration and the floor and the ceiling effects. Reliability was evaluated using Cronbach’s alpha coefficients for internal consistency and intraclass correlation coefficients (ICCs) for test retest reliability assessment with telephone interview. Construct validity was supported with convergent and discriminant validity using correlation among the MLHFQ and the SF-36 scores, exploratory factor analysis using principal axis factoring and oblique rotation with direct oblimin, and known-groups validity that referred to ability to discriminate subjects among different New York Heart Association (NYHA) classes. Responsiveness was assessed with effect size. It was found that average time of administration approximately was five minutes and there were high floor (11.1% to 27.2%) and no ceiling effect on the MLHFQ scores. Cronbach’s alpha coefficients and ICCs of the MLHFQ were 0.86 to 0.93 and 0.61 to 0.77, respectively. There were significantly moderate or high correlations among the MLHFQ scores and the assumed corresponding SF-36 subscales and component summary scores (Spearman rank order correlation; rho = -0.49 to -0.56, p &lt; 0.05). Twenty one items of the Thai version of the MLHFQ loaded on four factors such as physical, emotional, treatment, and symptoms dimensions. In addition, the MLHFQ scores discriminated among NYHA class I, II, and III (Kruskal-Wallis test, p &lt; 0.001). Moreover, most observed effect sizes on the MLHFQ were moderate. These results suggest that the MLHFQ (Thai version) indicates acceptable preliminary psychometric properties and agrees with the original version
DOI: 10.14457/cu.the.2009.1780
title: Effect of 12 weeks treadmill training with whole body vibration on bone markers in postmenopausal Thai women

description: Objectives: To study effects of 12 weeks treadmill training with whole body vibration on bone markers in postmenopausal Thai women. Materials and methods: The subjects were healthy Thai women with postmenopause at least 5 years aged between 55-65 years were recruited in this assessor-blinded randomized controlled trial. Forty-six (23 of treadmill training group ™ and 23 of treadmill with whole body vibration group (TM+WBV). TM group walked in treadmill with moderate intensity, 30 minutes per day, 3 times a week, for 12 weeks and TM + WBV group added a WBV exercise (1 minute bouts of vibration separated by 1-minute resting period, total 20 minutes) on reciprocating vertical displacement machine (30 Hz, amplitude 4mm.) by performing squat stance with knee-flexed 20º on platform after treadmill training. Biochemical bone markers (β-CrossLabs, PINP, NMID-Osteocalcin), Balance assessment (single leg stance with opened eyes), Walking speed (expand time up and go test), Physical performances (chair stand, step test and sit and reach test) were measured 1 week before training as baseline and after 12 weeks training. Results: Forty-three (21 of TM and 22 of TM + WBV) were completed study. Bone resorption and formation markers were significantly increased in both groups after training (p&lt;0.05). Balance and walking speed were increased in TM group but decreased in TM+WBV group. Bone markers, single leg stance with opened eyes, walking speed and physical performance were not significant difference between TM and TM + WBV groups (ANCOVA, p&gt;0.05). Conclusion: Effects on biochemical bone markers, balance walking speed and physical performances after 12 weeks treadmill training with whole body vibration are not significant difference from treadmill training alone in postmenopausal Thai women
DOI: 10.14457/cu.the.2009.1781
title: An enhancement of 3D fluid control using adaptive kernel estimation

description: In computer animation, animation tools are required for fluid-like motions which are controllable by users or animators. One of the popular and widely used methods for simulating fluid flow in computer graphics is Smoothed Particle Hydrodynamics (SPH). Although SPH is practical for applying to fluid movement control and also preserves efficiently properties of fluid flow, it is complicated to simulate various details in same flow. This study proposes an enhanced method based on Smoothed Particle Hydrodynamics (SPH) which is controllable and automatically kernel length adjustable in order to preserve small details; lost by fixed kernel. Reeb graph is used to construct a structure of an input object. To control fluid flow, we use a kind of particle control methods called Skeletal Particles. Skeletal Particles or control particles are placed on the center of smoothing kernel in computation step. To solve the problem caused by fixed kernel length, we implement the Adaptive Kernel Density Estimation (AKDE) technique into the computation step. Therefore, the smoothing length is dynamically adapted to all given points to be appropriate with density of their regions. As a result, the errors of unstable mean values of particles in low density regions are decreased