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Direct reprogramming of fibroblasts into endothelial progenitor cells by defined factors

http://repository.vnu.edu.vn/handle/VNU_123/29263 Quantile treatment effects are estimated to study the impacts of household credit access on health spending by poor households in one District of Ho Chi Minh City, Vietnam. There are significant positive effects of credit on the health budget shares of households with low health care spending. In contrast, when an average treatment effect is estimated, there is no discernible impact of credit access on health spending. Hence, typical approaches to studying heterogeneous credit impacts that only consider between-group differences and not differences over the distribution of outcomes may miss some heterogeneity of interest to policymakers. Introduction: Endothelial progenitor cells (EPCs) are important progenitor cells in vasculogenesis as well as in tissue engineering. However, few EPCs can be isolated from bone marrow, peripheral blood and umbilical cord blood. Moreover, their in vitro proliferation potential is also limited. Therefore, …
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Analysis and control of FGM plates integrated with piezoelectric sensors and actuators using cell-based smoothed discrete shear gap method (CS-DSG3)

http://repository.vnu.edu.vn/handle/VNU_123/28149 A cell-based smoothed discrete shear gap method (CS-DSG3) based on the first-order shear deformation theory was recently proposed for static and dynamics analyses of Mindlin plates. In this paper, the CS-DSG3 is extended for analysis and active vibration control of the functionally graded material (FGM) plates integrated with piezoelectric sensors and actuators. In the piezoelectric FGM plates, the properties of core material are assumed to be graded through the thickness by the power law distribution while the electric potential is assumed to be a linear function through the thickness of each piezoelectric sub-layer. A closed-loop control algorithm based on the displacement and velocity feedbacks is used to control static deflection and active vibration of piezoelectric FGM plates. Several numerical examples are conducted to demonstrate the reliability and accuracy of the proposed method compared to other available numerical results.
Ti…

Measuring University Students' Approaches to Learning Statistics: An Invariance Study

http://repository.vnu.edu.vn/handle/VNU_123/27799 The aim of the current study was to provide evidence that an abbreviated version of the Approaches and Study Skills Inventory for Students (ASSIST) was invariant across different languages and educational contexts in measuring university students’ learning approaches to statistics. 

Data were collected on samples of university students attending undergraduate introductory statistics courses in five countries (Argentina, Italy, Australia, Turkey, and Vietnam). Using factor analysis, we confirmed the three-factor (Deep, Surface, and Strategic approach) model holds across the five samples, and we provided evidence of configural and measurement invariance. The current version of the ASSIST for statistics learners is a suitable scale for researchers and teachers working in the field of statistics education and represents promising tool for multinational studies on approaches to learning statistics.
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Measuring University Students' App…

Ion Wind Generator Utilizing Bipolar Discharge in Parallel Pin Geometry

http://repository.vnu.edu.vn/handle/VNU_123/25859 We present a simple and efficient airflow generator utilizing the effect of ion wind by generating simultaneously both the positive and negative ions from two sharp electrodes mounted parallel to each other. The unique bipolar geometrical setup eliminates the effect of space charge by the high recombination rate of oppositely charged ions. 

The two-electrode arrangement is symmetrical, where the electrode creating charged ions of one polarity also serves as the reference electrode to establish the electric field required for ion creation by the opposite electrode, and vice versa. Unlike the conventional setup, with a single electrode generating ion wind with movement toward the reference electrode, in this configuration the air movement is parallel to the electrodes, and is directed away from the device. The airflow behavior is studied by both experiments and numerical simulation. The ion wind speed has a linear relationship with the squ…

Ba viên ngọc quý

http://repository.vnu.edu.vn/handle/VNU_123/53581 Trong thế giới vật lý, ngọc quý là vật do thiên nhiên tạo hóa, hiếm có, và vì thế có giá trị ở mặt đồng tiền, thẩm mỹ và quý hiếm. Song, những việc thuộc thế giới vật lý dù có giá trị đến đâu cũng có giới hạn của chúng ở trong vòng tương đối. 

Hơn thế nữa, ngọc quý cũng chẳng khác gì là đất đá vô tri, chúng không hề tự cho chúng có giá trị gì và tác hại gì cho nhân loại, chẳng qua là tâm hư vọng của con người dựng lập cho những viên ngọc ấy có giá trị khác nhau theo một hệ thống nào đó mà thôi. Một khi tâm con người đã kiến lập những khái niệm về giá trị của những viên ngọc ấy thì những tâm tham, sân, si lần lượt trỗi dậy. Cũng chính vì thế mà có sự tranh dành cướp đoạt lẫn nhau, mang đến những chết chóc, hận thù, khổ đau cho mình và người. Vậy thử hỏi những viên ngọc quý ấy có giá trị đích thật chung cùng gì cho mình, người, và toàn thể nhân loại? Chưa kể là người và vật đều bị chi phối bởi vô thường, khổ, vô ngã. Không có gì sinh mà khô…

Adsorptive Removal of Copper by Using Surfactant Modified Laterite Soil

http://repository.vnu.edu.vn/handle/VNU_123/28872


Removal of copper ion (Cu2+) by using surfactant modified laterite (SML) was investigated in the present study. Characterizations of laterite were examined by X-ray diffraction (XRD), Fourier transforminfrared spectroscopy (FT-IR), inductively coupled plasma mass spectrometry (ICP-MS), and total carbon analysis. 

The optimum conditions for removal of Cu2+ by adsorption using SMLwere systematically studied and found as pH 6, contact time 90 min, adsorbent dosage 5mg/mL, and ionic strength 10mM NaCl. The equilibrium concentration of copper ions was measured by flame atomic absorption spectrometry (F-AAS). Surface modification of laterite by anionic surfactant sodium dodecyl sulfate (SDS) induced a significant increase of the removal efficiency of Cu2+. 
The surface modifications of laterite by preadsorption of SDS and sequential adsorption of Cu2+ were also evaluated by XRD and FT-IR. The adsorption of Cu2+ onto SML increases with increasin…

Outcome versus process value in service delivery

http://repository.vnu.edu.vn/handle/VNU_123/29298 Purpose - This study is embedded in social exchange and transaction cost theories. The purpose of this paper is to compare the relative importance of process value and outcome value in building affective and cognitive relationship strength and to compare the relative effects of each type of relationship strength on attitudinal and behavioral loyalty. 

Design/methodology/approach - This empirical study features a quantitative approach. The sample comprises 167 business-to-business (B2B) customers of a large transportation and logistics company in Vietnam. Findings - Process value and outcome value have different effects on affective relationship strength. The effect of process value is greater than that of outcome value. In addition, cognitive strength has a stronger impact on both attitudinal and behavioral loyalty than affective strength. Research limitations/implications - These insights extend extant literature regarding the process a…