リプログラミング時のＸ染色体再活性化の解析

筑波大学 (University of Tsukuba)201

Essays on The Economics of Helath Care Payment Reforms

Both public and private health care sectors in the United States have been experimenting with many innovative payment methods with the aim of improving quality of care while containing the cost growth. For example, large employers and insurers in the private sector innovated their insurance design to encourage patients to make better decisions regarding to treatments and health care providers. In the public sector, Medicare recently implemented reforms on payments to physicians, hospitals and other health care facilities that incorporated quality-based bonuses. It also implemented policies such as “site-neutral payment” policies for different kinds of facilities that provide similar services in order to reduce unnecessary spending. In this thesis, I evaluate the impacts of some of such payment reforms on patients\u27 choice, quality of care, and healthcare spending. I also examine the relative importance of different components of health care policies, e.g., financial incentives versus quality and cost information provision. Finally, combining data with theory I predict the effects of a Medicare\u27s “site-neutral payment” policy and propose the optimal reimbursement and insurance policies for the outpatient care services. Policy makers in the US are increasingly tying payments for health care providers to their quality measures, although there is mixed empirical evidence on the performance of the current program. In the first chapter, I evaluate the impact on hospital quality of Medicare\u27s Hospital Value-Based Purchasing program, a large federal program which rewards hospital for quality of their service. I exploit the introduction of the incentive and the variations in incentives payment across hospitals to identify the program\u27s effects on hospital quality. I find that, compared to non-participating hospitals, participating hospitals on average improve on more than half of the patient experience outcomes after the program started. However, the magnitude of the improvement is rather small. There is no significant improvement in mortality rates. I also find that there exists some convergence in quality of the participating hospitals. That is, hospitals that expect lower value-based incentive payment in the future improve quality more than hospitals that expect more payment in the future. In the second chapter, I examine the relative importance of financial incentive and quality and cost information in changing healthcare consumer\u27s facility choices. I do so by exploiting the Reference Pricing (RP) program implemented by the California Public Employee\u27s Retirement System, which increased cost-sharing at expensive health care providers and provided enrollees with a clear comparison of quality between high-cost and low-cost providers. I find that the program led to a 30.4% increase in the probability of a patient choosing low-cost ambulatory surgery centers (ASCs) when in need of a procedure covered by the RP. The program also led to a 22.6% increase in the probability of a patient choosing ASCs when in need of a procedure related to RP procedures but not directly impacted by the RP financially. The presence of the large spillover effect suggests the importance of the information the RP provided patients with. Furthermore, the demand estimation pre-RP and post-RP shows that patients with RP procedures are more sensitive to price and less sensitive to distance and their health risk after the RP. Their perception of HOPDs\u27 quality drops significantly while that of ASCs\u27 quality stays the same. I estimate that the financial incentive change in the RP program explains about 15% of the total demand change, while the change in patient\u27s perception of facility quality explains about 70%. In the final chapter, I study how Medicare can achieve greater efficiency by jointly optimizing its reimbursement structure and insurance design for the outpatient services performed in hospital outpatient departments and ambulatory surgery centers. Using large datasets on Medicare claims and providers\u27 financials, I find that current Medicare reimbursement rates are significantly above marginal costs for both HOPDs and ASCs, and that ASCs offer equal or higher net value than HOPDs for common outpatient procedure groups. I develop a theoretical model to characterize the optimal reimbursement rates and coinsurance rates. I demonstrate that reimbursement rates should be set at providers\u27 marginal costs, and that coinsurance rates should be higher for HOPDs than for ASCs. Counterfactual analyses show that moving from current practice to the proposed optimal policy would reduce Medicare spending by 15% to 23%, while simultaneously increasing the social surplus by 3.1% to 6.4%. In contrast, if coinsurance rates are constrained to be the same across provider types, as in the current Medicare insurance policy, more limited welfare improvements are still possible by increasing reimbursements rates for HOPDs to incentivize greater sorting into ASCs. Under such scenarios, I estimate an increase in social surplus of 3.1% to 6.1% and Medicare savings of 9% to 15% instead. Lastly, I show that Medicare\u27s recent policy change, which decreased HOPDs\u27 reimbursement rates to ASCs\u27 rates while keeping the coinsurance rates the same, resulted in social surplus reduction

リプログラミング時のＸ染色体再活性化の解析

筑波大学 (University of Tsukuba)201

The Impacts of Task-Based Activities on Learners’ Grammatical Acquisition and Motivation at Dong Nai Technology University

The study aims to measure the effect of Task-based language teaching on grammatical achievement and the motivation of EFL learners at Dong Nai Technology University. The research will conduct a quick grammar test to administer 48 students at the school to achieve this goal. After sitting the test, the learners will undergo a 6-week course applying task-based language teaching. Before the treatment, one certified instructor-made grammar test about the learning units will be encompassed as the pre-test. Furthermore, a motivation questionnaire will be carried out in this group at the research's beginning and end. Afterward, the learners will learn through the treatment, which is learning through the implementation of Task-based language teaching. After six weeks of treatment, the group will take the same teacher-made grammar test as the post-test. After that, the writer will analyze the data through paired sample t-test. The results demonstrated a significant difference between the pre-test and post-test in the student’s performance on grammar acquisition and the enhancement in learners’ motivation. Based on the findings of this research, it is believed that task-based language teaching can be used in English classes to enhance learners’ grammar achievements and motivation among Vietnamese university learners

Characterization of O-glycan binding lectin from the red alga Hydropuntia eucheumatoides

The red alga, Hydropuntia eucheumatoides is one of the algal genera from which agar is commercially extracted, and is the main source of agar in the world. The lectin HEL from the red alga H. eucheumatoides was isolated by a combination of aqueous ethanol extraction, ethanol precipitation, ion exchange and filtration chromatography. Lectin gave a single band with molecular mass of 17,000 Da in both non-reducing and reducing SDS-PAGE conditions, therefore lectin exists in monomeric form. The hemagglutination activities of HEL were stable over a wide range of pH from 3 to 10, temperature up 60 oC and not affected by either the presence of EDTA or addition of divalent cations, indicating that lectin requires no metal for biological activity. The hemagglutination activities of HEL were not inhibited by monosaccharides and glycoproteins, D-glucose, D-mannose, D-galactose, D-xylose, N-acety-D-mannosamine, transferin, fetuin and yeast mannan, but strongly inhibited by monosaccharides containing  acetamido groups at equatorial C2 position, such as N-acetyl-galactosamine, N-acetyl-glucosamine, N-acetyl-neuraminic acid and glycoprotein porcine stomach mucin bearing O-glycans. Thus, lectin is specific for O-glycans and  may recognize the sequences GalNAcαSer/Thr, GalNAc(α1-3)[Fuc(α1-2)]Gal(β1-4)GlcNAc(β1-3)GalNAc- and GluNAc(α1-4)Gal- under interacting with the acetamido groups at equatorial C2 position of the terminal sugar residues in oligosaccharide structures of O-glycans. The red alga H. eucheumatoides could promise to be a source of valuable lectins for application in biochemistry and biomedicine

The Impact of Job Satisfaction on Job Performance of Tax Officials: An Empirical Study in Vietnam

Purpose: The level of employee satisfaction with the use of e-tax systems is a major factor influencing the success of such systems. While studies typically focus on taxpayers' perspectives, this research investigates the influence of perceived ease of use, IT background, incentives, and social influence on tax officials’ job performance, mediated by tax officials’ job satisfaction.   Theoretical framework: The research is based on the Theory of Planned Behavior (TPB) and Technology Acceptance Model (TAM) to propose the research model which analyze the impact of job satisfaction on job performance.    Design/Methodology/Approach: A quantitative approach was adopted, involving surveys administered to tax officials in Vietnam. The study analyzed 250 valid responses using Cronbach's test, Exploratory Factor Analysis (EFA), Confirmatory Factor Analysis (CFA), and Structural Equation Modeling (SEM).   Findings: The research revealed that all four factors significantly influence job performance through job satisfaction of tax officials in Vietnam. These findings provide valuable insights for tax authorities to improve job performance.   Research, Practical & Social implications: The research results contribute to other countries with similar characteristics in devising strategies to enhance employee performance. However, its limitations include its generalizability to other e-tax systems and countries. Future research with a larger sample size could bolster the applicability of these findings nationally.   Originality/Value: The research suggests tax authorities to support tax officials improve their professional skills; improve the regulations, policies on salary and bonus for tax officials; assist tax officials in using the e-tax system; implement effective communication

Experimental Evaluation on Engineering Properties and Drying Shrinkage of No-Cement Mortar Produced by Alkaline Activation of Fly Ash-Slag Mixtures

Turning locally available industrial by-products such as fly ash (FA) and ground granulated blast-furnace slag (GGBFS) into cement-free materials has been recently received much attention from researchers. Following this trend, the present study produces alkali-activated mortars (AAFS) using a mixture of FA and GGBFS as a precursor activated by an alkaline solution of sodium hydroxide and sodium silicate. Five AAFS mixtures were prepared for the evaluation of engineering properties, drying shrinkage, and microstructural observation using various FA/GGBFS ratios of 30/70, 40/60, 50/50, 60/40, and 70/30. The experimental results show that the proportions of FA and GGBFS significantly affected the performance of the AAFS in both fresh and hardened stages. Higher GGBFS content resulted in a reduction in flowability and higher fresh unit weight. The GGBFS-rich AAFS developed its mechanical strength faster than the FA-rich AAFS and the strength gain of the GGBFS-rich AAFS was significantly higher than that of the cement-based mortar at only 1-day old, confirming the applicability of AAFS as a structural material and its potential to replace cement in the no-cement mortar production. The AAFS sample incorporating 60% of GGBFS and 40% of FA exhibited the highest strength, lowest water absorption, and less drying shrinkage with a relatively dense microstructure among the AAFS samples

Erratum: Mott Transition in the Mass Imbalanced Ionic Hubbard Model at Half Filling

Erratum: Mott Transition in the Mass Imbalanced Ionic Hubbard Model at Half Filling[Nguyen Thi Hai Yen, Le Duc Anh, Hoang Anh Tuan, Nguyen Toan Thang and Tran Thi Thu Trang, Communications in Physics, Vol. 29, No. 3SI (2019), pp. 305-312]This paper was published on 22 October 2019 with an omission in the text of the author’s list. The author list should read asNGUYEN THI HAI YEN$^1$, LE DUC ANH$^2$, HOANG ANH TUAN$^{1,3,\dagger}$, NGUYEN TOAN THANG$^1$, TRAN THI THU TRANG$^4$ AND NGUYEN THI HUONG$^5$$^1$Institute of Physics, Vietnam Academy of Science and Technology (VAST), Hanoi, Vietnam $^2$Hanoi National University of Education, Hanoi, Vietnam $^3$Graduate University of Science and Technology, VAST, Hanoi, Vietnam $^4$Ha Long University, Quang Ninh, Vietnam $^5$Thuy Loi University, Hanoi, Vietnam$^{\dagger}$E-mail: [email protected] author’s list has been corrected as of 29 November 2019. The author’s list has been corrected in the electronic version of the journal

Verifying the Reliability of Impressed Current Method to Simulate Natural Corrosion in Reinforced Concrete

In order to accelerate the corrosion of steel reinforcement in the reinforced concrete structures for laboratory research, the impressed current method has been used widely regardless of the appropriacy of this method on the various aims of the studies relating to the deterioration of the reinforced concrete structures. The aim of this study is to characterize the influence of the impressed current method on the steel-concrete interface in the reinforced concrete to verify the reliability of this method on simulating the natural corrosion. The mill-scale of the steel reinforcement and the steel-concrete interfacial region were investigated using SEM-EDS. The results indicate that impressed current can induce the non-uniform and localized corrosion on the steel reinforcement. The corrosion products formed were likely to the natural corrosion induced by chloride environments. However, the oxidization of OH- at anode can inhibit the precipitation of corrosion products at steel-concrete interfacial region and then slowing down the formation of crack in concrete. This positively leads to an overestimation of load capacity of corroded structure and raises doubt on utilizing this technique to simulate the corrosion behavior