1,417 research outputs found

    A Study of the use of computational concept mapping situated in an authentic learning context (CCMAL) in enhancing English as a Foreign Language (EFL) students’ metacognition in reading comprehension classes

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    This thesis described a convergent mixed method research which aims to investigate the influence of computational concept mapping situated in an authentic learning context (CCMAL) on students’ metacognition in English as a foreign language (EFL) reading comprehension classes. A hundred first year English non-majored students were invited for this study. The students participated a two-hour session on a weekly basis during a seven-week reading course. While the fifty students of the experimental group (EG) were exposed to CCMAL, the fifty students of the control group (CG) were exposed to a traditional teaching environment during the reading course. Data was collected through the pre and post-test on reading comprehension, pre and post-survey on metacognition, students’ computational concept maps collected in week 1, week 4 and week 7 of the reading course, weekly learning journals and classroom observation, and individual interviews after the reading course. The study found that the students of the EG outperformed those of the CG in the post-test on reading comprehension. In terms of reading comprehension skills, data showed that CCMAL had positive influence on the students’ use of literal skills, interpretive and inferential skills. The study also found that CCMAL had a positive influence on the students’ metacognition. Specifically, CCMAL was found to have the greatest influence on students’ scores on monitoring followed by evaluation. However, there were no significant differences on the students’ scores on planning. The utilisation of CCMAL positively influence students’ use of metacognitive strategies, such as planning, monitoring and evaluation. Furthermore, the study discovered that the students’ CCMAL learning experience was influenced by factors as the relevance between the reading text topics and the students’ experiences, the students’ individual differences, and the affordances of Cmap which was the concept mapping software in this study. In conclusion, this study found that the use of CCMAL had positive influence on students’ metacognition and reading comprehension. It is recommended that CCMAL be widely used in reading comprehension classes to enhance students’ reading achievements. Moreover, it recommended further research into concept mapping related topics for improving the quality of English education in Vietnamese context

    On the Governance of Innovation: Institutional Ownership vs. Stock Price

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    Firms can change their outstanding shares to manage their stock price levels. Those with lower stock prices tend to attract more speculative trading, which causes higher price volatility and may force their managers to excessively focus on short-term earnings at the expense of R&D and other long-term projects. Thus, I hypothesize that keeping high stock price levels allows firms to (i) limit speculative traders’ influences on stock prices and thus mitigate investor short-termism, and (ii) enhance R&D productivity. Indeed, I find that high-priced firms are less likely to cut R&D to reverse an earnings decline, less likely to fire their CEOs, and have more innovation. All these findings are robust after controlling for institutional ownership, a factor that has been shown in the literature to have a correlation with share price and also have a significant impact on R&D policies and innovation. For robustness checks, I examine stock splits, which allow mangers to re-set their stock price levels, and IPOs in which managers set an offering price range before shares are publicly traded. Consistent with my hypothesis, I discover that innovative firms are less likely to split their stocks, and that innovation declines after firms split their stocks. Furthermore, IPO firms that set higher offering prices, not those that attract more institutional ownership, have more future innovation. Thus, the results imply that, rather than being “forced” or “assured” by institutional investors to innovate as the extant literature suggests, managers of innovative firms actively support high stock price levels to foster innovation

    Intravenous Administration of Iron Oxide Nanoparticles in the Chicken Model

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    To be used in health care, the safety and effectiveness of nanoparticles needs to be tested in a living organism. The objective of this project was to develop the chicken as a convenient animal model to examine tissue targeting of intravenously (i.v.)-injected iron oxide (IO) nanoparticles. In Experiment 1, different doses of IO-COOH were i.v. injected into chickens; blood was collected at 0, 5, 15, 30, and 60 minutes post-injection; liver, spleen, lung, and kidney were collected after the last blood collection. For Experiment 2, IO-COOH and IO-PEG were i.v. injected into chickens; blood and the organs were collected at 0, 5, 15, 30, and 60 minutes postinjection. For both Experiments, IO concentration in blood was examined by iron test kit and fixed tissue sections were stained with H/E and Prussian blue stain. Portions of organs from Experiment 2 were frozen and used for preparation of homogenates and tissue-sections for immunohistochemical and/or iron-staining. For Experiment 3, the dermis of growing feathers (GF) was injected with mouse-IgG antigen (Ag); 6 hours later, IO-Ab (IO-COOH conjugated with chicken-antibody specific for mouse IgG), IO-COOH, or IO-PEG were i.v. injected into the chickens; one Ag-injected GF and one uninjected GF per chicken was collected at 0, 0.1, 0.5, 1, 2, 24, and 48 hours post-i.v.-injection; organs were collected at three and seven days post-i.v.- injection; and tissue sections of GFs and organs were stained with Prussian blue stain. Together, results of Experiment 1 and Experiment 2 revealed that IO-nanoparticles were taken up quickly by macrophages in liver and spleen, whereby IO-PEG was taken up at lower levels and slower pace by phagocytic cells when compared to IO-COOH. Experiment 3 was not successful in demonstrating delivery of intravenously injected IO nanoparticles to antigen-injected GFs. This may be due to the low dose of nanoparticles injected as well as the antigen-antibody system used. This is the first report describing organ-distribution and uptake of i.v. injected IO nanoparticles in the chicken system, setting the stage for using the avian model to test in vivo targeting effectiveness of nanoparticles

    Developing a validity argument for the English placement Fall 2010 Listening test at Iowa State University

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    The study was aimed at examining the usefulness of the English Placement Listening test (EPT) in Fall 2010 at Iowa State University (ISU) by using the current argument-based validation approach with a focus on four main inferences constructing the validity argument. Both qualitative and quantitative methods were employed. The results contributed both positive and negative attributes to the validity argument for the EPT Listening Fall 2010 test. The qualitative examination on the test specification and the test booklet showed that the test was authentic with a good distribution of question types and test item indices. In specific, the 30 test items were equally divided into comprehension and inference questions with 90% and 70% of them falling within an acceptable difficulty range, and an acceptable discrimination range respectively. General statistical analyses of the EPT Listening Fall 2010 test score set of 556 test takers produced a normal distribution with a reliability of nearly 0.70. Moreover, the correlation analyses among different set scores of the EPT Fall 2010 test takers supported the usefulness of the EPT test in discriminating proficiencies of the test takers besides their TOEFL scores. However, numerous weaknesses were detected such as an incomplete test specification, weak strengths of the correlational relationships between the EPT test and the TOEFL tests (r\u3c0.6). The study provided an evidence on the importance of the operation of the EPT test at ISU and lead to some recommendations on supporting the validity argument for the test

    Investigating the Language Learning Potential of Data-driven Teaching Materials on Source Use for College Students in a Writing Course

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    This report documents the results of the investigation into the language learning potential of data-driven teaching materials on source use for undergraduates in a college-level writing course at a large land-grant Midwestern university. The investigation is a part of a large project which comprises three major stages: linguistic analyses on source use of 149 documented essays written by college students, development of data-driven materials on source use, and evaluation of the materials. The data-driven teaching materials consist of a corpus-based web tool and a computer-delivered online lesson on source use. The corpus-based web tool provides examples of citing sentences in the collection of 79 A-graded essays as concordance lines which help illustrate different features of source use, and displays graphs showing frequency distributions of citing sentences across sub-categories of each feature of source use. The computer-delivered online lesson contains two major tasks each of which has questions that guide students to observe the use of a feature of source use in the corpus-based web tool. This report summarizes key findings of the implementation of the materials in a naturalistic instructional setting. These findings focus on the language learning potential of the materials which concerns two major aspects: (1) whether the pedagogical design characteristics of the materials led to the students’ hypothesized learning processes (i.e., noticing and focusing on features of source use), and (2) whether the students gained any knowledge, skills, and awareness about source use after the training

    ANTI-ODOUR TREATMENT ON 100% WOOL FABRIC USING COLORANTS FROM COFFEE GROUND RESIDUES

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    Coffee ground residues is considered as biomass and organic wastes that can be used for further application due to their deodorant properties. The purpose of this study is applying anti-odor treatment on 100% wool fabric by bi-functional dyeing process with colorant extracted from coffee ground residues. The extraction was done with water at 100ÂşC with different extracting ratio. The knitted wool fabrics were IR dyed with extracting solutions at 80ÂşC, 90 min, then dried at 60ÂşC, 30 min. The effectiveness of treatment on wool fabric was determined by colour strength K/S and FT-IR spectra. The colour fastness after hand wash were tested by AATCC standard to confirm the treatment after laundering, exhibited good color fastness at grade 4-5. The anti-odor effect was also evaluated according to AATCC 2017 Methods for Odor Evaluation of Textiles and other Materials for fabric before and after laundering, which proved the efficiency of deodorization of treated fabric by coffee residues extraction, even with strong odor like onio

    Activity of fungal and bacterial endophytes for the biological control of the root-knot nematode <em>Meloidogyne graminicola</em> in rice under oxic and anoxic soil conditions

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    Two endophytic Fusarium moniliforme isolates Fe1 and Fe14, an endophytic bacterium Bacillus megaterium Bm and a rhizosphere Trichoderma isolate T30 with known antagonistic activity toward the root-knot nematode Meloidogyne graminicola were studied for bio-enhancement of rice under glasshouse conditions. The level of colonization of Fe1 and Fe14 in the rice root under oxic and anoxic soil environments was investigated. The fungi were inoculated twice to the rice seeds using seed treatment and soil drenching methods at a rate of 106 cfu/ seed and 105 cfu/ seedling respectively. Both Fe1 and Fe14 isolates colonized well in the rice roots under oxic and anoxic soil water regimes with colonization rate ranged between 50-89%. The fungi colonized all parts of the roots though the preferable zone was the root periphery. The level of colonization decreased over time, from 56% after 8 weeks to 27% after 12 weeks of incubation. Both isolates did not show consistent effect on the growth of rice. The mechanisms of action of the endophytic F. moniliforme isolate Fe14 was studied intensively under glasshouse conditions. In these experiments, Fe14 was also inoculated twice by seed coating and soil drenching techniques. The fungus reduced nematode penetration into the rice root significantly by up to 55% compared to the control. In a split-root experimental design, the fungus showed induced systemic resistance in rice when one half of the root system was treated with fungal spores while the other half was inoculated with the root-knot nematode. Root exudates from fungal treated plants showed repellent effect toward M. graminicola in a plastic test chamber. Fe14 also altered nematode development expressing by significantly higher number of males in fungal treated plants. Furthermore, Fe14 reduced the number of females and number of eggs per female compared to those of the control treatment. In addition, Fe14 exhibited high level of biocontrol under anoxic soil conditions by reducing the total number of nematodes in the endorhiza significantly by 45%. Influence of inoculation time and method on biocontrol efficacy of Fe14 was also evaluated. In the first test, the ability of Fe14 for early protection of M. graminicola was tested in comparison to other antagonistic fungi. Out of the five fungi tested, F. moniliforme Fe1 and Fe14, F. oxysporum Fo162, Fusarium F28 and Trichoderma T30, only Trichoderma T30 was able to reduce nematode infestation in rice seedlings when both nematode and fungi were inoculated at sowing. However, Fe14 remained its biocontrol activity against the rice root-knot nematode 10 weeks after fungal inoculation. The effectiveness of different inoculation methods of Fe14 was also investigated. Both seed treatment and soil drenching methods led to similarly significant reductions in nematode damage. Double inoculations of Fe14, one at sowing and the other one repeated three weeks later did not result in significantly higher biocontrol level compared to single inoculation at sowing. To enhance biocontrol efficacy, Fe14 was combined with Trichoderma T30 and the endophytic bacterium B. megaterium Bm in various greenhouse experiments. The three antagonists were first tested for their compatibility in vitro. No clear mutual exclusive was observed in any pair tests. Dual application of Fe14 and T30 in vivo reduced nematode infestation significantly compared to the control but the difference between single and combined treatments was not significant. Similarly, when Fe14 was combined simultaneously or in a staggered time manner with T30 and Bm, galling severity caused by M. graminicola significantly reduced by 20-70% compared to the control. However, none of the combinations led to significantly higher level of biocontrol compared to single applications and thus, single treatments of each biocontrol agent was adequate.Wirksamkeit pilzlicher und bakterieller Endophyten für die Bekämpfung der Wuzelgallennematode Meloidogyne graminicola an Reis unter aeroben und anaeroben Bedingungen Für die biologische Kontrolle von Meloidogyne graminicola unter kontollierten Bedingungen wurden zwei endophytische Isolate von Fusarium moniliforme (Fe1 und Fe14), ein endophytisches Bakterium Bacillus megaterium Bm und ein Rhizosphärenisolat Trichoderma T30 mit bekannten antagonistischen Wirkungen genutzt. Die Kolonisationsraten von Fe1 und Fe14 in der Reiswurzel unter aeroben und anaeroben Bedingungen wurden untersucht. Der Pilz wurde zweimal an die Reissamen inokuliert, jeweils durch Samenbeizung und Tauchinokulation mit einer Rate von 106 cfu/ Samen und 105 cfu/ Pflanze. Beide Isolate Fe1 und Fe14 kolonisierten die Reiswurzeln undter anaeroben und aeroben Bedingungen mit Raten von 50 bis 89%. Der Pilz kolonisierte alle Teile der Wurzel, wobei die hauptsächliche Besiedlung an der Wurzelperipherie lag. Die Kolonisation ging über die Zeit zurück, von 56% nach 8 Wochen auf 27% nach 12 Wochen Inkubationszeit. Beide Isolate zeigten keinen Effekt auf das Wachstum der Reispflanzen. Die Wirkungsweise des Endophyten F. moniliforme Isolat Fe14 wurde unter Gewächshausbedingungen intensiv untersucht. In diesen Experimenten wurde der Pilz ebenfalls zweimal durch Samenbeizung und Tauchinokulation zu den Pflanzen gegeben. Der Pilz reduzierte die Nematodenpenetration signifikant um bis zu 55% im Vergleich zur Kontrolle. Durch ein experimentelles Design in welchem die Wurzeln räumlich voneinander getrennt wurden, wurde eine induzierte Resistenz an Reis nachgewiesen. Hierbei wurde nur eine Hälfte des Wurzelsystems mit Sporen des Endophyten behandelt und die andere Hälfte mit Nematoden inokuliert. Wurzelexudate der pilzlich behandelten Pflanzen zeigten eine abweisende Wirkung gegen M. graminicola in Plastiktestkammerversuchen. Fe14 verursachte eine Verschiebung des Geschlechtsverhältnisses. Die Anzahl der Weibchen und die Anzahl der Eier pro Weibchen wurde im Vergleich zur Kontrollvariante reduziert. Zusätzlich wurde eine sehr starke biologische Konrolle durch Fe14 unter anaeroben Bedingungen erziehlt. Die Anzahl der Nematoden in der Endorhiza wurde um 45% reduziert. Der Einfluß der Inokulationszeit und -methode auf biologische Kontrollaktivität von Fe14 wurde ebenfalls untersucht. Im ersten Test wurde die Fähigkeit von Fe14 für die frühzeitige Kontrolle von M. graminicola im Vergleich zu anderen antagonistischen Pilzen untersucht. Von den fünf getesteten Pilzen, F. moniliforme Fe1 und Fe14, F. oxysporum Fo162, Fusarium F28 und Trichoderma T30, konnte nur Trichoderma T30 die Nematodenpopulation reduzieren, wenn Nematode und Pilz zur Saat inokuliert wurden. Die Effektivität verschiedener Inokulationsmethoden wurde an Fe14 ebenso untersucht. Sowohl die Samenbeizung als auch die Tauchinokulation führten zur signifikanten Reduktion der Nematodenpopulation. Um die biologische Kontrollaktivität zu erhöhen, wurde Fe14 mit Trichoderma T30 und B. megaterium kombiniert. Dadurch wurde die Vergallung der Wurzeln um 20-70% signifikant reduziert, jedoch zeigten sich keine Unterschiede in der Reduktion der Nematodenpopulation durch einzel oder kombinierte Inokulation der verschiedenen Organismen
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