cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.5063/f1gm85nm
title: The independent effects of nutrient enrichment and pulsed nutrient delivery on a common wetland invader and its native conspecific

description: Human activities often lead natural systems to be nutrient enriched, with anthropogenically derived nutrients commonly delivered in discrete pulses. Both nutrient enrichment and nutrient pulses can impact plant performance and phenotypic plasticity, especially in invasive species, but quantifying their independent effects remains challenging. To explore the effects of nutrient enrichment and nutrient pulse magnitude, we established a common garden experiment using the North American wetland invader Phragmites australis and its native conspecific Phragmites australis subsp. americanus (five source populations each). We exposed plants to three levels of nutrient enrichment that were delivered either in small or large magnitude pulses, examining productivity and plasticity responses over a single growing season. Productivity and biomass allocation differed by lineage, with invasive Phragmites producing 73% more biomass and 66% more culms, but with the native growing 31% taller and allocating more of its biomass belowground. Contrary to expectations, both lineages responded similarly to nutrient enrichment and were similarly plastic in their traits. Nutrient enrichment, rather than nutrient pulses, led to large productivity gains and trait plasticity magnitudes. However, total biomass and leaf-level traits (specific leaf area and chlorophyll concentration) were responsive to variation in nutrient pulse magnitudes. By decoupling the effects of nutrient enrichment from nutrient pulses, our study demonstrates the independent effects of these two key factors for plant performance and, by extension, invasion success. We report trait-based similarities between two lineages of Phragmites that play contrasting ecological roles in North American wetlands, and we highlight the potentially detrimental effects of nutrient pulses.Published in Oecologica (conditionally accepted as of 22 July 2019). Frevola, DM and SM Hovick.
DOI: 10.14457/cu.the.2007.1825
title: The effects of types of corrective feedback on students’ oral pragmatic competence on the use of refusals

description: This experimental study was designed to investigate the effects of two corrective feedback techniques—explicit feedback and prompts—on L2 pragmatic acquisition, focusing on the use of refusals. The research aims to study the effects of explicit feedback and prompts on learners’ 1) oral refusal production, 2) pragmatic awareness of the use of refusals, and 3) level of confidence in making appropriate refusals. The participants were 39 first year English-major undergraduates of Silpakorn University. The subjects were pre-tested and categorized as high- and low-proficiency learners before assignment to two experimental groups and one control group. Each experimental group received either explicit feedback (+ immediate time/ - self-directed repair) or prompts (+ immediate time/ + self-directed repair) as their treatment, while the control group received delayed explicit feedback (- immediate time/ - self-directed repair). After the 10-week instructional intervention, the subjects were post-tested on their pragmatic production, awareness and confidence. The delayed post-test was done 13 weeks later to investigate the retention of each corrective feedback technique. Results from the study revealed that the prompts group (PG) benefited the most, vastly improving their refusal production. The PG significantly outperformed the explicit feedback group (EG) and the control group (CG) on both immediate and delayed post-tests with the difference between groups becoming more robust over time. The PG also significantly improved their pragmatic awareness compared to the other two groups on the post-test. However, the CG was found to have the greatest improvement of their confidence level after the treatment. The findings were interpreted as indicating the beneficial role of immediate corrective feedback and the superiority of prompts over explicit feedback in promoting learners’ acquisition of L2 pragmatics.
DOI: 10.14457/cu.the.2007.1826
title: Effects of using a strategy-based training program on attitudes and self-access English language learning behaviors of upper secondary school students

description: The Ministry of Education has promoted self-access English language learning at the basic education level since 2002 and established Student English Access Rooms (SEARs) in 80 secondary schools throughout Thailand to support students’ self-access learning. In order to assist students to learn in self-access centers effectively, suitable orientation and training need to be provided (Detaramani and Chan, 1999; Miller, 2000; and Rujikietgumjorn, 2000). The researcher, therefore, developed a strategy-based training program in order to help prepare students to make effective use of self-access English language learning. The purpose of this present study was to examine the effects of this strategy-based training program on attitudes and self-access English language learning behaviors of upper secondary school students. The study was designed as a single group experimental research study that employed both quantitative and qualitative research methods. The participants were 37 eleventh grade students at Saraburiwitthayakhom School in the first semester of academic year 2007. The treatment used in this study was a strategy-based training program and the research instruments were a questionnaire and learner journals. Paired samples t-test was employed to investigate the differences between the students’ attitudes and self-access English language learning behaviors before and after the training program. The data obtained from the learner journals were analyzed using a focused coding. The findings revealed from both the quantitative and qualitative data supported that the strategy-based training program can enhance attitudes and self-access English language learning behaviors of upper secondary school students. The participants gained more positive attitudes towards self-access English language learning. They realized their roles in self-access English language learning and gained more confidence in their English language capabilities. For the data concerning self-access English language learning behaviors, the participants were found to conduct self-access English language learning more frequently and systematically. Thus, students should receive a strategy-based training program in order to increase effective self-access English language learning.
DOI: 10.14457/cu.the.2007.1827
title: Dialogue in world English literatures : a comparison of parent-child conversations in short stories from three varieties of English

description: Within the Southeast Asian region, Malaysia, Singapore, and the Philippines maintain the largest communities of writers of locally produced English fiction. The English used in Malaysia and Singapore can be regarded as one variety, distinct from Philippine English and other more widely used varieties. This research analyzed 39 contemporary works of literary short fiction which depicted interaction between parents and their pre-adolescent children. The stories were written in English by local authors in Malaysia, Singapore, the Philippines, and North America. Stylistic analysis employing a framework of discourse (speech) moves and acts was applied to all of the parent-child dialogues in the stories. This analysis describes how authors depict these relationships through the literary representation of verbal and non-verbal communication. Quantification and detailed analysis of the data reveal differences in how parent-child interactions are portrayed by authors in different cultures. Though universal aspects of parent-child discourse were found, the Malaysian and Singaporean dialogues were oriented toward hierarchical status relationships, and the North American stories portrayed relationships which were oriented toward egalitarian parenting while the Filipino stories demonstrated a balance of the two values but with the most interactive conversational style. This research demonstrates how Stylistics and contemporary English world literature can be used for cross-cultural comparisons and exploration of the sociosemiotic function of literature.
DOI: 10.14457/cu.the.2007.1828
title: Heterogeneous esterification of free fatty acids using ion exchanged ETS-10 base catalyst

description: Engelhard titanosilicate-10 (ETS-10) was synthesized via hydrothermal crystallization in the absence of organic template and seed. The influence of SiO₂/TiO₂ mole ratio of the initial gel on the formation of ETS-10 was examined in system 5SiO2: xTiO2: 3NaOH: KF: 75H₂O, where x was varied between 0.5-1.0. In addition, base-modified ETS-10 could be prepared by ion-exchange method with various alkali cation i.e. NaOH, KOH, RbOH and CsOH•H₂O in order to increase basic site of catalyst. The synthesized materials were characterized by powder X-ray diffraction (XRD), N₂-adsorption/desorption, DR-UV spectroscopy, scanning electron microscopy (SEM), inductively coupled plasma-atomic emission spectroscopy (ICP-AES) and atomic absorption spectrophotometry (AAS) techniques. The synthetic materials are mainly cubic-like particle ETS-10 phase with pore size around 0.6 nm. All synthesized materials were tested their activities in esterification of oleic, palmitic and linoleic acid with methanol to produce fatty acid methyl ester (biodiesel). The various reaction conditions such as catalyst amount, methanol to oil mole ratio including reaction time and temperature were studied. From this study, Rb-ETS-10 was distinguishable in both oleic acid and palmitic acid esterification. The optimum condition is methanol to acid mole ratio 9 to 1, reaction temperature 110-120℃, reaction time 18-24 h, amount of catalyst 10 wt% with stirring speed 200 rpm. The maximum methyl ester yield reached 100% when reaction was carried out under the optimum condition. Moreover, catalytic activities of reused and regenerated Rb-ETS-10 catalysts were also investigated.
DOI: 10.5526/erdr-00000114
title: Workflow Satisfiability Problem with User-Independent Constraints: Instances, Instance Generator and Algorithms
DOI: 10.14457/cu.the.2007.1829
title: Chemical and physical compatibility of lanthanum nickel iron oxides and yttria stabilized zirconia

description: The chemical and physical compatibilities of the candidates, LaNi[subscript 1-x] Fe[subscript x] O[subscript 3] (LNF) perovskites and K[subscript 2] NiF[subscript 4]–typed La[subscript 2] Ni[subscript 1-x] F[subscript x] O[subscript 4] (L[SUBSCRIPT 2] NF), of a cathode material for solid oxide fuel cell with the commercial solid electrolyte, 8 mol % Yttria Stabilized Zirconia (8-YSZ), were- studied. Firstly, LNF and L[SUBSCRIPT 2] NF with x = 0-1.0 were prepared by Water Citrate (WC) and Modified Water Citrate (MWC) methods, and characterized by XRD. It was found that the single phased LNF perovskites were synthesized successfully by both methods at 700-900 ℃ for 5h. As x is 0-0.5, the crystal structure is cubic and rhombohedral at the calcination temperature of 700 ℃ and 900 ℃, respectively. The further investigation indicated that the cubic structure changed to the rhombohedral structure at 900 ℃, and was stable up to 1200 ℃. As x is 0.6-1.0, the crystal structure is in the orthorhombic phase at both calcination temperatures. This orthorhombic phase decomposed at 1200 ℃. The single-phased L[SUBSCRIPT 2] NF systems were achieved only that of x = 0 and 0.1 after calcination at 900 ℃. The crystal structure of L[SUBSCRIPT 2] NF is tetragonal. In all cases, the lattice constants and the volume per formula unit in all series generally increased as the Fe content increased. Following the reaction by XRD and SEM-EDX, the stoichiometric La(Ni[subscript 0.6] Fe[subscript 0.4])O[subscript 3] and La[subscript 2](Ni[subscript 0.9] Fe[subscript 0.1])O[subscript 4] have a good chemical compatibility with 8-YSZ from room temperature up to 900 ℃. In the case of the non-stoichiometric La(Ni[subscript 0.6] Fe[subscript 0.4])[subscript y] O[subscript 3] and La[subscript 2](Ni[subscript 0.9] Fe[subscript 0.1])[subscript y] O[subscript 4] (y = 0.95 and 1.05), the chemical compatibility with 8-YSZ is good up to 800 ℃. In addition the thermal expansion coefficients of La(Ni[subscript 0.6]Fe[subscript 0.4])O[subscript 3] and La[subscript 2](Ni[subscript 0.9]Fe[subscript 0.1])O4 are 13.2 x 10[superscript -6] K[superscript -1] and 12.7 x 10[superscript -6] K[superscript -1], respectively. These values are close to that of 8-YSZ; therefore, lanthanum nickel iron oxide of both structures have a good physical compatibility with 8-YSZ.
DOI: 10.14457/cu.the.2007.1830
title: Polyelectrolyte multilayer coating on electrospun cellulose acetate fibrous membrane for desalination

description: Electrostatic multilayers of chitosan (CHI) with sodium alginate (SA) and poly (styrene sulfonate) sodium salt (PSS) were alternatively coated on electrospun cellulose acetate (CA) fiber mat. Morphologies of the composite membranes were characterized by scanning electron microscope (SEM). The morphology of the CHI/SA coated membrane was denser than the CHI/PSS coated membrane. Functional groups of the top layers were quite clear with carboxyl (1,596 and 1,411 cm-1) and sulfonic (1,007 and 1,035 cm-1) for SA and PSS, respectively. Amino groups of CHI were only presented in slight quantity. X-ray photoelectron spectroscopy (XPS) confirmed the deposition of amino groups from CHI on multilayer membrane surface. These membranes were characterized for its pure water permeability. It was found that the flux of water decreased with increasing the number of bilayers. The pure water flux was in the range of 60 L m¯² h¯¹ for 15 bilayers and 40 L m¯² h¯¹ for 25 bilayers. The sodium chloride (NaCl) solution flux was lower than the pure water flux due to the effect of osmotic pressure, and this flux decreased with increasing NaCl concentration. The rejection of NaCl increased substantially with the number of bilayers of the polyelectrolytes multilayers. The level of NaCl rejection from this work was in the range of 15 % for 25 bilayers and 6 % for 15 bilayers.
DOI: 10.14457/cu.the.2007.1831
title: Effects of doping metal ions on structures and properties of perovskites Ba0.5Sr0.5Co0.8Fe0.2O3-δ

description: Doped with Pr and La ions at the A site and Mg, Ni, Zn, and Cu ions at the B site, Ba[subscript 0.5]Sr[subscript 0.5]Co[subscript 0.8]Fe[subscript 0.2]O[subscript 3-δ] (BSCF5582) perovskites were synthesized by the modified citrate method. As the results, characterized by XRD and SEM, the Pr, La, Zn, and Cu specimens showed homogeneous and single phase with cubic perovskite structure, except Cu–doped BSCF5582 by replacing 0.1 mol Fe. O[subscript 2]–TPD results demonstrated that the oxygen vacancies can be improved by doping A site and/or B site with metal ions. The electrical conductivity of BSCF5582 doped with metal ions at A site gradually increased with the amount of the metal ions (Pr and La). However, metal doping at the B site ions decreased the electrical conductivity. Also, the oxygen vacancies and electrical conductivity of BSCF5582 doped with metals at both A and B site were less than that of only A site. Doping with 0.2 mol La at the A site of BSCF5582 gave the material with the highest electrical conductivity (419.6 S/cm at 450℃), which was about 8 times higher than that of BSCF5582 (53.7 S/cm at 500℃). At high temperature, the thermal expansions coefficient of Pr or La specimens increased with the enhancement of Pr or La contents, due to the loss of lattice oxygen that caused the formation of oxygen vacancies in the perovskite structure.
DOI: 10.14457/cu.the.2007.1832
title: An optimum pulse shape design for ultra-wideband systems with timing jitter

description: Ultra-wideband (UWB) technology offers a promising solution to the radio frequency (RF) spectrum drought by allowing new services to coexist with current radio systems with minimal or no interference. Two crucial keys to communications success of UWB systems are pulse transmission power and timing jitter effects. Since the Federal Communications Commission (FCC) published its standard for the limitation of effective isotropic radiation power (EIRP) for UWB systems in 2002, the problem of spectrum shaping for UWB systems came to the forefront of scientific discourse. The interference of pulse transmission power to and from existing systems operating over the same frequency may reduce the advantages of UWB systems. On the other hand, timing jitter which results from the presence of non-ideal sampling clocks in practical receivers causes distortion. This distortion affects the correlation of signals at the receiver and thereby reducing the signal detection ability of UWB systems. This is a serious problem because the UWB pulse duration is very short so only small timing misalignment can severely affect the performance of a correlation detector. This dissertation presents a novel technique in designing the optimum pulse shape for UWB systems under the presence of timing jitter. The proposed pulse attains the adequate power to survive the noise floor and simultaneously provides good resistance to timing jitter. It also meets the power spectral mask restriction as prescribed by the FCC for indoor UWB systems. In addition, parameters of the proposed optimization algorithm are also investigated. Moreover, this study proposes a novel design of orthogonal pulses to improve the capacity of UWB systems. This orthogonal pulse design is based on the optimum pulse we propose. Therefore, all of the orthogonal pulses now have the same properties as the optimum proposed pulse. These properties include power spectral density (PSD) that meets the FCC spectral masks and simultaneously resists timing jitter. Additionally, each of the orthogonal pulses is mutually orthogonal to other pulses. The simulation results have demonstrated several relevant merits of the optimum proposed pulse over the previously known pulses, namely the lowest bit error rate (BER) of the optimum proposed pulse is achieved in the system with the imperfect timing jitter at room temperature. For the orthogonal pulses, the simulation results confirm the orthogonality properties of the orthogonal proposed pulses and show the advantages of the novel design over others.
DOI: 10.14457/cu.the.2007.1833
title: The effects of extensive reading plus activities on the development of reading and writing skills and perceptions of undergraduate students

description: The study investigated the effects of ER Plus activities on (1) three sub-skills of reading ability, i.e. reading comprehension, reading speed, and reading comprehension of narratives; (2) writing ability and the relationships and developmental patterns of reading amounts and writing scores; and (3) students’ perceptions on the development of their reading strategies and motivation over time. The subjects of the study were 34 second-year EFL students majoring in Finance and Banking who were enrolled in the Fundamental Reading Course in the first semester of the academic year 2007 at Nakhon Pathom Rajabhat University. All were randomly selected to participate in the 15-week study that was made up of three consecutive periods (150 minutes in total) per week of traditional reading instruction plus motivating activities and silent reading. The subjects were also required to read simplified readers of their choice outside class, record the amounts of reading, answer a perception survey, be interviewed by the teacher after they finished each book, and take a writing test at three time points, each five weeks apart. After the treatment period, all of the subjects’ reading amounts were totaled, and, based on the total, the subjects were divided into two groups: high and low with an average reading amounts of 364 and 147 pages, respectively. The findings revealed that: (1) the high group significantly improved their reading comprehension ability and reading speed at .05 level, while the low group did not, and both the high and the low groups were not different in reading comprehension of narratives; (2) the low group had significant differences in their writing scores between the first and second and the first and third, whereas the high group had no significant improvement, and there was neither correlation nor systematic developmental patterns between reading amounts and writing scores; and (3) the subjects in both groups had a tendency to utilize more efficient reading strategies and had increased motivation to read that corresponded with their increased reading amounts.
DOI: 10.14457/cu.the.2007.1834
title: Preparation of chitosan particles using ultrasonic atomization for controlled drug release

description: Chitosan particles with the sizes ranging from 250 to 1,520 nm was prepared from chitosan solution using an electrospray equipped with an ultrasonic atomizer. The chitosan particles were spherical and had smooth surface. The effects of preparation parameters on particle size were investigated. The size of dry chitosan particles tended to increase but not statistically significant when the molecular weights increased from 47 to 238 kDa. But in the hydrated state the particle sizes incresed significantly with increasing the MW. In order to get small CS particle size, CS with high DD and low CS concentration should be used. Increasing the lidocaine drug content tended to significantly increase the size of dry particles but not the hydrated particles. Increasing in hydrogen bonding between chitosan and lidocaine was observed by IR analysis. The lidocaine content within CS-LC-Ps was increased with the increasing drug to chitosan ratio but decreased with chitosan molecular weight increased. The entrapment efficiency of 90% could be successfully achieved. Up to 92% of lidocaine was released from chitosan particles into phosphate buffer solution (pH 7.4) at 37 °C within the period of 3 hours with no significant burst of drug during the initial hydrated stage. Finally, a simulated skin permeation study of the lidocaine from chitosan particles using shed snake skin and cellulose membrane demonstrated that lidocaine was continuously released from the particles for up to 6 hours of study
DOI: 10.14457/cu.the.2007.1835
title: Multiple directorships, firm performance and corporate governance of firms in Thailand

description: This thesis generates novel empirical evidence on Thai corporate governance in respect of the multiple-directorship impact on firm performance with classifying the directors into two types, executive and non-executive ones. Employing the sample of Thai listed firms in 1993 – 2005, this paper unfolds that boards in which directors serving a number of seats penalize firm’s market performance, but such boards create more value to the company in terms of accounting value. Besides, when exploring the relations by each type of directors, it is found that the directions of those relationships still remain unchanged for both types. In addition, when investigating over the time of pre- and post-Asian financial crisis in 1997, this thesis discovers that the types of director do matter. Also, there is some evidence that Thai firm’s governance is constantly ameliorated after the crisis. What’s more, when examining those relations according to the potential agency problems, this paper finds that the associations of boards in which non-executive directors holding numerous directorships with firm value are actually driven by the probable agency problems.