MÔĐUN BẤT BIẾN ĐẲNG CẤU TRÊN VÀNH GOLDIE PHẢI

In this paper, we study some properties of automorphism invariant modules on the right Goldie ring and state some properties related to this class of modules. In addition, we confirmed some problems related to the nonsingular automorphism invariant ring.Trong bài báo này, chúng tôi nghiên cứu một số kết quả về môđun bất biến đẳng cấu trên vành Goldie phải, đồng thời nêu một số tính chất liên quan đến lớp các môđun này. Ngoài ra, chúng tôi cũng khẳng định một số vấn đề liên quan đến lớp vành bất biến đẳng cấu không suy biến

Simple synthesis of floating Fe2O3/Luffa catalysts for the photo-Fenton degradation of methyl orange at near neutral pH

Although widely used in the textile industry, methyl orange is considered one of the most toxic dyes, which have negative impacts on the aquatic environment and needs to be removed from water bodies. Hence, the present paper reports the synthesis of new floating photo-Fenton catalysts based on the immobilization of Fe2O3 nanoparticles on the surface of Luffa sponges for the oxalate-induced-degradation of methyl orange. The floating catalytic sponges were prepared through a simple precipitation method followed by a reflux heating process and then characterized by field emission scanning electron microscopy, X-ray diffraction, atomic absorption spectrometry, and nitrogen adsorption-desorption experiments. According to the experimental results, methyl orange was effectively degraded over our floating catalytic sponges under light illumination at near neutral pH. The catalytic activity was also found to be enhanced with the increase in crystallinity of Fe2O3 nanoparticles, which can be achieved by the reflux heating. Besides, owing to the floating feature, these sponges are easily separated from the solution, thereby not forming a secondary source of pollution for wate

Survey on Vietnamese teachers’ perspectives and perceived support during COVID-19

The COVID-19 pandemic has caused unprecedented damage to the educational system worldwide. Besides the measurable economic impacts in the short-term and long-term, there is intangible destruction within educational institutions. In particular, teachers – the most critical intellectual resources of any schools – have to face various types of financial, physical, and mental struggles due to COVID-19. To capture the current context of more than one million Vietnamese teachers during COVID-19, we distributed an e- survey to more than 2,500 randomly selected teachers from two major teacher communities on Facebook from 6th to 11th April 2020. From over 373 responses, we excluded the observations which violated our cross-check questions and retained 294 observations for further analysis. This dataset includes: (i) Demographics of participants; (ii) Teachers' perspectives regarding the operation of teaching activities during the pandemic; (iii) Teachers' received support from their schools, government bodies, other stakeholders such as teacher unions, and parents' associations; and (iv) teachers' evaluation of school readiness toward digital transformation. Further, the dataset was supplemented with an additional question on the teachers' primary source of professional development activities during the pandemic

Optimization of Total Flavonoid Extraction From the Helicteres hirsuta Lour. Roots by Bath Ultrasound Assisted method and cytotoxic activities of these Flavonoids

This study was carried out to optimize the various approaches to analyze the effects of various variables on the total flavonoid content extraction from the roots of Helicteres hirsuta L. The existence of various compounds in the methanol fraction was accessed by using LC-MS/MS analysis. The results of the study identified the ideal parameters such as times (30 minutes); methanol solvent concentration (50%); ultrasonic frequency (12 Hz); and material/solvent ratio [1:30 (w/v)] for extracting the highest total flavonoids from the roots of H. Hirsuta. The study's results suggested that the total flavonoid value was 3.52684 (mg Catechin/g extract). The verified experiment obtained an actual value of 5.205 (mg Catechin/g extract). Further, the results of the study suggested the presence of 20 compounds of a flavonoid nature (66.667%) appearing in the purified methanol fractional extract. These compounds can inhibit DPPH free radicals at 50%, with an IC50 value of 536.760 g/mL, and they also have inhibitory activity on the growth of cancer cell lines with IC50 values ranging from 115.81 and 219.17g/mL. The human leukemia cell line (HL-60) exhibits the most significant cytotoxic response to a methanol extract from H. hirsuta root with an IC50 value of 115.81 g/mL

Factors affecting the creativity of high school students

Creativity is a vital personality quality of each individual. Each person has their potential for creativity, and it can be nurtured and developed in an appropriate and safe environment. The purpose of the study was to find out which factors from schools and students themselves affect creativity as well as the association between creativity and age, gender and giftedness of students, which then a basis to adjust and establish appropriate methods from schools, families, and students themselves to develop elements and their creativity. The study was conducted on 108 high school students in three grades from giftedness and non-giftedness schools. The data was collected through a survey method using a self-constructed questionnaire and drawing creativity test TCT-DP to determine students' creativity levels and personal information. The study's finding, which uses mathematical methods and one-way analysis of variance, reveals that factors affecting elements and creativity level are objective factors including education environment from school; behavior of teachers, and subjective factors including interests, perspectives, and thoughts of students. It was also found that there were no significant differences in the components of creativity and creativity among students in different grades, gender, and groups of giftedness schools

Fabrication and Evaluation of the Photocatalytic, Antibacterial Activity of Ag–TiO2_2 Thin Film

Ag–TiO2 thin film was fabricated by DC magnetron sputtering and photoreduction methods. Characteristics of the film such as surface area, crystal structure, and chemical composition were investigated by using scanning electron microscope (SEM), X–ray diffractometry (XRD) and UV–vis spectra. The photocatalytic activity of Ag–TiO2 thin film was determined by the degradation of methylene blue (MB) solution under various irradiation conditions. The antibacterial property of Ag–TiO2 thin film was conducted in E. coli bacteria. Results showed that the photocatalytic and antibacterial property of Ag–TiO2 thin film are better than those of pure TiO2 thin film in the visible region. Ag–TiO2 thin film shows a great potential application in the antibacterial and environment field

Research to support and inform the development, implementation and/or evaluation of tobacco control policies in relation to the framework convention on tobacco control in low and middle-income countries

In order to enforce policies on tobacco control in Vietnam, reliable information on health and socio-economic hazards associated with tobacco farming is needed. The study investigates the harmful impact of tobacco cultivation and processing on health of tobacco farmers in a rural community in northern Vietnam. Objectives included estimation of health care costs as well as health beliefs related to tobacco cultivation and processing. The health of those who cultivate the crop is constantly put in peril. The study confirms that tobacco farming does not bring prosperity to the farmers while causing them a lot of health problems, especially among women

TiO 2

An improved photocatalytic activity of semiconductor materials using incorporation of the noble metals such as Ag, Au, and Pt is a promising technology. In this study, Ag nanoparticle-TiO2 nanotube structures (Ag-TNTs) have been investigated as a photocatalyst in different irradiation conditions using different characterization techniques. The results indicate that Ag nanoparticles dispersed uniformly on the TNTs’ surface without any change in TNTs’ morphology. In addition, Ag-TNTs exhibited lower photoactivity than the TNTs under UV irradiation. In contrast, Ag-TNTs increased the photoactivity in comparison with TNTs and the photocatalytic performance under sunlight irradiation. These phenomena could be contributed to the appearance of Ag nanoparticles on the nanotube surface