Factors Affecting the Profitability of Cement Manufacturing Enterprises in Tuyen Quang Province

This study focuses on analyzing the factors affecting the production and business efficiency of cement manufacturing enterprises in Tuyen Quang province. Production and business efficiency is measured by profitability ratios including return on assets (ROA), return on equity (ROE) and return on sales (ROS). Using a quantitative research method through estimating a linear regression model based on data of two cement manufacturing companies in the period 2019-2021, the research results show that the factors affecting business efficiency of cement manufacturing enterprises in Tuyen Quang province include size of enterprise, cost ratio, average collection period, inventory turnover, fixed assets turnover and debt ratio

Chemical constituents from the leaves of Styrax argentifolius H.L. Li and their antioxidative activity

Searching for bioactive agents from medicinal plants, the phytochemical investigation on the EtOAc extract of the Vietnamese Styrax argentifolius leaves has resulted in the isolation and structural determination of five compounds, including one nor-neolignan egonoic acid (1), one lignan (+)-pinoresinol (2), one sterol (20R)-3β-hydroxysitgmasta-5,22-dien-7-one (3), and two triterpenoids lupeol (4), and 2α,3α,24-trihydroxy-urs-12-en-28-oic acid (5). The chemical structures of these secondary metabolites were elucidated by NMR and MS spectral data. All isolated compounds were first observed in S. argentifolius species. Sterol 3 and triterpenoid 5 were detected in genus Styrax for the first time. With the IC50 value of 19.10 µg/mL, compound 2 possessed the strong activity in DPPH radical scavenging assay

Challenges of Implementing Outcome-Based Assessment in Vietnamese Higher Education – A Qualitative Inquiry

This qualitative study investigates the key challenges faced by university lecturers in implementing outcome-based assessments (OBA) in higher education institutions in Vietnam, a country currently undergoing significant educational transformation. Utilizing a qualitative research design, the study conducted semi-structured interviews with 15 lecturers from diverse academic fields in a institution. The data were thematically coded and interpreted through the lenses of Constructivism, Institutional Theory, and Diffusion of Innovations Theory. Nine major challenges emerged from the findings, including pedagogical hurdles, lack of training and resources, institutional constraints, and technological limitations. These challenges are contextualized within the existing theoretical frameworks and related literature. The study offers critical insights that are deeply rooted in cultural, institutional, and structural variables. These findings are pertinent for educators, administrators, and policymakers in Vietnam and potentially for those in similar educational settings, and they hold broader implications for professional development, institutional policies, technological infrastructure, and cultural shifts within the educational landscape

In-action reflective teaching in Vietnam: A qualitative exploration of practices, influences and implications

Reflective teaching plays a crucial role in the field of education though its intricacies in particular cultural contexts like Vietnam are still little understood. This study aims to investigate reflective teaching practices in more detail within the context of Vietnamese education.  This study used a qualitative methodology and semi-structured interviews with twelve Vietnamese teachers, each representing a different stage of their careers to shed light on the many forms of in-action reflective practices and their implementation, benefits, drawbacks and even cultural influences. The results of this in-depth investigation provided an overview of the wide range of in-action reflective practices that are actively used in the classroom.  The enhancement of adaptive teaching methodologies and the bolstering of student engagement are prominent among the many advantages that were noted.  Teaching in the Vietnamese context also presents unique challenges. Teachers often struggle with the demands of multitasking, the complexities of navigating uncertainties in real-time classroom scenarios   and the predominant challenge of managing large class sizes. Moreover, it was surprising to learn how many Vietnamese cultural, social   and educational factors influenced teacher understanding and use of in-action reflection.  The understanding of reflective teaching practices is enhanced by the research findings which also have broad implications for areas such as instructional strategies, teacher preparation programmes, academic research perspectives and even the development of educational policies.  The study strongly emphasizes the pressing need for more context-specific investigations into reflective teaching and underscores the indispensable role of reflection in fostering an environment conducive to effective teaching and learning

Multi-faceted identities of teacher assessors: A qualitative study in the Vietnamese educational context

Within the educational landscape of Vietnam, the professional identity of teachers when acting as assessors remains a comparatively uncharted domain and requires further explorations. Consequently, this qualitative investigation was initiated to delve deeper into the intricate identities Vietnamese teachers adopt in their capacities as assessors. Relying upon frameworks such as Constructivist Grounded Theory and Identity Theory, the study meticulously analyzed self-reported narratives from 15 tertiary lecturers based in Vietnam. Through this rigorous analysis, a spectrum of fifteen distinct identities was uncovered. These identities included “Gatekeepers of Knowledge and Competency”, “Nurturers”, “Diplomatists”, “Auditors”, “Confusian Sages”, “Innovators”, “Social Justice Advocators”, “Cultural Mediators”, “Emotional Anchors”, “Scalfolders”, “Technological Navigators”, “Lifelong Learners”, “Community Builders”, “Ethical Guardians”, and “Democratic Facilitators.” Intriguingly, these identities were not merely seen as additional layers to their professional duties; instead, they emerged as foundational components of teachers’ professional self-image. The forces molding these roles are diverse, encompassing deep-seated cultural values, prevailing educational paradigms, and personal lived experiences of educators. Unraveling these identities offers consequential implications for the broader educational sector. It underscores the imperative to holistically re-envision teacher training programs and assessment design, ensuring they resonate with the multifaceted roles educators play in steering both academic achievements and wider societal outcomes

chemical constituents from methanolic extract of Garcinia mackeaniana leaves and their antioxidant activity

A phytochemical investigation of the methanolic extract of Garcinia mackeaniana leaves led to the isolation, and determination of five secondary metabolites, including one benzophenone 4,3',4'-trihydroxy-2,6-dimethoxybenzophenone (1), two flavone C-glucosides vitexin (2) and its 2''-O-acetyl derivative (3), one biflavone amentoflavone (4), and one mono-phenol methyl protocatechuate (5). The chemical structures of these compounds were characterized by the NMR-spectroscopic method. These isolated compounds were isolated from G. mackeaniana species for the first time. Benzophenone derivative 1 has shown to be associated with a significant IC50 value of 14.97±0.8 µg/mL in the DPPH-antioxidant assay

Cytotoxic naphthoquinones from Diospyros fleuryana leaves

In the search for anti-cancer plants in Vietnam, the leaves of Diospyros fleuryana were selected for chemical investigation. Phytochemical analysis of the ethyl acetate (EtOAc) extract led to the isolation of two naphthoquinones isodiospyrin (1), and 8'-hydroxyisodiospyrin (2), and one isoflavone 7-O-methylbiochanin A (3). The chemical structures of isolated compounds were determined by 1D-NMR (1H, and 13C-NMR), 2D-NMR spectra (HSQC, and HMBC), and MS spectroscopy. Compound 3 was isolated from genus Diospyros for the first time. Regarding the strong IC50 values of 2.27, and 8.0 µM against KB, and Hep cell lines respectively, cytotoxic examination suggested that compound 2 is a promising agent in anti-cancer treatment.Â

Environmental isues of mining activities in Tay Nguyen

Intensive mining activities, specially illegal, negatively affect environment in Tay Nguyen. Mining of gold and tin placers, sand and pebble disturbed the landscape, changed river bed caussing river bank erosion. Exploited wastes from mine, for example, kaolin mine in Loc Chau (Lam Dong province) destroyed and retrograded tea land. There observed evidences of acid mine drainage and pollution of heavy metal including Cu, Pb, Hg, et.c in surface water, stream sediments and soils from some gold mines such as Dak Ripen (Kon Tum), Krong A (Dak Lak) and Tra Nang (Lam Dong). Main causes of mining environmental problems are failure of management, so the first and most important measure of mitigation is to improve the management of mining activities.ReferencesBorisenko A.S., Trần Trọng Hòa, V.I. Vasilev, N.K. Morsev, Vũ Văn Vấn, Ngô Thị Phượng, Hoàng Hữu Thành, Trần Tuấn Anh, Phạm Thị Dung, 2008: Phát hiện lần đầu tiên khoáng vật Jonassonite - AuBi5S4 ở Việt Nam. Tạp chí Các Khoa học về Trái Đất, T.30, (3), tr.193-198. Damigos D., 2006: An overview of environmental valuation methods for the mining industry. Journal of Cleaner Production, Volume 14, Issues 3-4, P. 234-247 Dixon-Hardy, D.W. Engels, J.M., 2007: Guidelines and Recommendations for the Safe Operation of Tailings Management Facilities. - Environmental Engineering Science, 24 (5), 14-26. Doolittle, J.J., Frisbee, N.M. and Hossner, L.R., 1992: Evaluation of acid-base accounting techniques used in surface-mine reclamation, Proc. 1992 Meeting of the American Society of Surface Mining and Reclamation, 14-18 June, Duluth, MN, p68-76. Trần Trọng Hòa, Ngô Thi Phượng, Borisenko A.S., Izokh A.E., Vũ Văn Vấn, Bùi Ấn Niên, Trần Tuấn Anh, Phạm Thị Dung, 2005: Đặc điểm địa hóa-đồng vị của quặng hóa vàng Mesozoi sớm và Mesozoi muộn trong mối liên quan với hoạt động magma rìa Đông Nam địa khối Đông Dương. Tạp chí Địa chất, Loạt A, số 295, tr.15-24. Nguyễn Kim Hoàng, Nguyễn Văn Mài, 2010: Đặc điểm khoáng hóa và triển vọng vàng gốc Trà Năng, tỉnh Lâm Đồng. Đại học Quốc gia Tp. HCM. Nilsson J-A, Randhem J., 2008: Environmental Impacts and Health Aspects in the Mining Industry. Department of Energy and Environment. Division of Environmental Systems Analysis. Chambers University of Technology. Göteborg, Sweden, 2008. publications.lib.chalmers.se/records/fulltext/85984.pdf‎ Plumlee, G.S. and Nash, J.T., 1995: Geoenvironmental models of mineral deposits--fundamentals and applications. U.S. Geol. Survey Open-File Report 95-831, p.1-18. Lê Văn Thành, 2004: Khai thác khoáng sản và tác động đến môi trường. Địa chất, N.281 Vũ Văn Vấn, Trần Trọng Hòa, A.S. Borisenko, Ngô Thị Phượng, Trần Tuấn Anh, Trần Hồng Lam, Đặng Trung Thuận, Phạm Thị Dung, 2007: Quặng hóa vàng Tà Năng, đới cấu trúc Đà Lạt: Điều kiện hình thành và bối cảnh địa động lực. Tạp chí Các Khoa học về Trái Đất, T.29, (2), tr.154-160. Báo cáo hiện trạng môi trường tỉnh Lâm Đồng giai đoạn 2006 - 2010: Sở Tài nguyên và Môi trường Lâm Đồng. http://www.lamdong.gov.vn/vi-VN/a/sotnmt/du-lieu-so/moi-truong/Pages/baocaohientrang2006-2010.aspx. Guidebook for Evaluating Mining Project EIAs, 2010: www.elaw.org/files/mining-eia-guidebook/Chapter1.pdf Global Acid Rock Drainage Guide (http://www.gardguide.com/index.php/Main_Page) UNEP, 1997: Industry and environment, mining and sustainable development. http://www.uneptie.org/vol20no4.htmO; 1997.

Assessment of heavy metal pollution in abandoned Giap Lai pyrite mine (Phu Tho Province)

Giap Lai pyrite mine had been exploited in the period 1975 - 1999, and abandoned after the mine became closed. This work is conducted with the aim to evaluate the impacts of the abandoned mine to the environment. 23 surface water, 15 ground water and 20 soil samples from the mining area were collected for experiments. Acid production potential and metal leaching of waste materials from tailings were tested. Results show that acid rock drainage (ARD) in the old mining area still occurs, with sulfide-rich tailings and waste rocks being sources of ARD, causing elevated metal concentrations in downstream water bodies. Surface water shows significant pollution of Fe, Mn, Ni and partially As. In the rainy season, the percentage of surface water samples having low pH values as well as metal contents in samples is higher than in the dry season. Metal concentrations in ground water are generally low, but many samples have low pH values, indicating the influence of the ARD. The geo-accumulation index reveals that soil from mining area is moderately contaminated with Ni, Cu, Hg and partially As. Most of the polluted samples are located near old mining pits, waste dumps and tailing ponds. The study also shows that negative effect of Giap Lai pyrite mine on the surrounding water and soil has been ongoing. However, no post-closure remediation measures have been applied at the mine, so there must be appropriate solutions for the acid mine drainage treatment before its being discharged to the environment. Given the facts revealed by this study, it is recommended that the Environmental Protection Law should be fully implemented at mining sites not only during the exploitation but also after their closures.References AMIRA, 2002. ARD Test Handbook. Project P387A Prediction Kinetic Control of Acid  Mine Drainage. AMIRA international May 2002, 42p. Çevik, F., Göksu, M. Z. L.,  Derici, O. B., Fındık,  Ö., 2009. An assessment of metal pollution in surface sediments of Seyhan dam by using enrichment factor, geoaccumulation index and statistical analyses. Environmental Monitoring and Assessment 152, 309-317. EPA, 2000. Abandoned mine site characterization and cleanup hand book, 129p, (https://yosemite.epa.gov/r10/amscch.pdf). Ghrefat, H.A., Abu-Rukah, Y., Rosen, M.A., 2011. Application of  geoaccumulation index and enrichment factor for assessing metal contamination in the sediments of Kafrain Dam, Jordan. Environmental Monitoring and Assessment 178, 95-109. IAEA, 2000. Reference Sheet, reference material. Trace elements in soil. (https://nucleus.iaea.org/rpst/Documents/rs_iaea-soil-7.pdf). INAP, 2009. Global Acid Rock Drainage Guide. International Network for Acid Prevention. (http://www.gardguide.com/index.php/Main_Page). Loska, K., Wiechula, D., Korus, I. 2004. Metal contamination of farming soils affected by industry. Environment International, 30(2), 159-165. MCMPR/MCA, 2010. Strategic Framework for Managing Abandoned Mines in the Minerals Industry, http://www.industry.gov.au/resource/Mining/Documents/StrategicFrameworkforManagingAbandonedMines.pdf. Mhlongo, S.E. and Amponsah-Dacosta, F., 2015. A review of problems and solutions of abandoned mines in South Africa, International Journal of Mining, Reclamation and Environment, DOI: 10.1080/17480930.2015.1044046. Müller, G., 1969. Index of geoaccumulation in sediments of the Rhine River. Geojournal 2, 108-118. Newton, G., et al, 2000. California’s Abandoned Mines. A Report on the Magnitude and Scope of the Issue in the State, Vol.1, 60p. Http://www.conservation.ca.gov/omr/abandoned_mine_lands/AML_Report/Documents/volume1textonly.pdf Nordstrom, D.K., Alpers, C.N., 1999. Geochemistry of acid mine waste. In “Review in Economic Geology, the environmental geochemistry of ore deposits”/Eds. G.S.Plumlee, M.J. Logsdon. Part A: Processes, techniques, and health issues Vol.6A, 133-160. Nowrouzi, M. and Pourkhabbaz, A., 2014. Application of geoaccumulation index and enrichment factor for assessing metal contamination in the sediments of Hara Biosphere Reserve, Iran. Chemical Speciation and Bioavailability,  26(2),99-105. Pham Tich Xuan, Nguyen Van Pho, Hoang Tuyet Nga, Doan Thi Thu Tra, Cai Van Truong, Nguyen Van Thu, Vu Manh Long, 2010. Heavy metal pollution in some metal mines in the Northern Vietnam. Procceding of Conference in commemoration of the 35th day of Establish of VAST. Environment and Energy, Hanoi, 236-244 (in Vietnamese with English abstract). Sobek, A.A., Schuller, W.A., Freeman, J.R. and Smith, R.M., 1978. Field and laboratory methods applicable to overburden and minesoils. Report EPA 600/2-78-054, US Environmental Protection Agency, 204p. Tarras-Wahlberg N.H, Lan T. Nguyen, 2008. Environmental regulatory failure and metal contamination at the Giap Lai pyrite mine, Northern Vietnam. Journal of Environmental Management, 86(4), 712-720. Tran Xuan Toan, 1963. Some characteristics of pyrite mineralization in the Giap Lai deposit, Phu Thọ. Geology 10, 18-24, Hanoi (in Vietnamese). Wei, Z., Wang, D., Zhou, H., Qi, Z., 2011. Assessment of Soil Heavy Metal Pollution with Principal Component Analysis and Geoaccumulation Index. Procedia Environmental Sciences, 10, 1946 -1952. Zawadzki, J and  P. Fabijan´czyk, P., 2013. Geostatistical evaluation of lead and zinc concentration in soils of an old mining area with complex land management. Int. J. Environ. Sci. Technol. 10, 729-742. Ziemkiewicz, P., J. Renton and T. Rymer, 1991. Prediction and Control of Acid Mine Drainage: Effect of Rock Type and Amendment. Proceedings Twelfth Annual West Virginia Surface Mine Drainage Task Force Symposium, April 3-4, Morgantown, West Virginia, Vol.1, 51-54

The burden and characteristics of enteric fever at a healthcare facility in a densely populated area of Kathmandu

Enteric fever, caused by Salmonella enterica serovars Typhi and Paratyphi A (S. Typhi and S. Paratyphi A) remains a major public health problem in many settings. The disease is limited to locations with poor sanitation which facilitates the transmission of the infecting organisms. Efficacious and inexpensive vaccines are available for S. Typhi, yet are not commonly deployed to control the disease. Lack of vaccination is due partly to uncertainty of the disease burden arising from a paucity of epidemiological information in key locations. We have collected and analyzed data from 3,898 cases of blood culture-confirmed enteric fever from Patan Hospital in Lalitpur Sub-Metropolitan City (LSMC), between June 2005 and May 2009. Demographic data was available for a subset of these patients (n = 527) that were resident in LSMC and who were enrolled in trials. We show a considerable burden of enteric fever caused by S. Typhi (2,672; 68.5%) and S. Paratyphi A (1,226; 31.5%) at this Hospital over a four year period, which correlate with seasonal fluctuations in rainfall. We found that local population density was not related to incidence and we identified a focus of infections in the east of LSMC. With data from patients resident in LSMC we found that the median age of those with S. Typhi (16 years) was significantly less than S. Paratyphi A (20 years) and that males aged 15 to 25 were disproportionately infected. Our findings provide a snapshot into the epidemiological patterns of enteric fever in Kathmandu. The uneven distribution of enteric fever patients within the population suggests local variation in risk factors, such as contaminated drinking water. These findings are important for initiating a vaccination scheme and improvements in sanitation. We suggest any such intervention should be implemented throughout the LSMC area.This work was supported by The Wellcome Trust, Euston Road, London, United Kingdom. MFB is supported by the Medical Research Council (grant G0600718). SB is supported by an OAK foundation fellowship through Oxford University