Impacts of pollution discharges from Dinh Vu industrial zone on water quality in the Hai Phong coastal area

The hydrodynamic and water quality models (the Delft3D model) were established based on the measured data and the estimated pollution discharges from Dinh Vu industrial zones to Nam Trieu estuary. With seven separate simulation scenarios, the results show that in case of increased wastewater with the control of pollution discharge (water and concentration), the impact of pollution is only limited to a small area around the discharge point. Their influences on water quality in other areas in Nam Trieu estuary are quite small. Meanwhile, in case of environmental risk, a strongly increasing pollution load would cause the significantly increasing pollutant concentration in this area, they have almost exceeded the value in the National Technical Regulation on surface water quality (QCVN 10-MT:2015/BTNMT), such as NH4, COD, and BOD. Dissolved oxygen in the water would also decrease significantly. The spatial influence extends from the discharge point to Nam Trieu estuary, inside Cam, Bach Dang rivers, and Cat Hai coastal area

Numerical solution of the problems for plates on some complex partial internal supports

In the recent works, Dang and Truong proposed an iterative method for solving some problems of plates on one, two and three line partial internal supports (LPISs), and a cross internal support. In nature they are problems with strongly mixed boundary conditions for biharmonic equation. For this reason the method combines a domain decomposition technique with the reduction of the order of the equation from four to two. In this study, the method is developed for plates on internal supports of more complex configurations. Namely, we examine the cases of symmetric rectangular and H-shape supports, where the computational domain after reducing to the first quadrant of the plate is divided into three subdomains. Also, we consider the case of asymmetric rectangular support where the computational domain needs to be divided into 9 subdomains. The problems under consideration are reduced to sequences of weak mixed boundary value problems for the Poisson equation, which are solved by difference method. The performed numerical experiments show the effectiveness of the iterative method

Impact of sea level rise on current and wave in Van Uc coastal area

This paper presents the results of analysis, comparison of some characteristics of current, wave at Van Uc estuary area when being affected by sea level rise due to climate change based on Delft3D model. Scenario groups are established: The current scenario and the scenarios simulating effect of sea level rise 0.5 m and 1.0 m. The results of calculation and simulation show that the velocity values change locally when sea level rises: Rise in the northern and southern areas (0.2–5 cm/s); decrease in the navigation channel (0.6–30 cm/s). Sea level rise causes the increase of wave height in the coastal area (13.5–43.8% in the dry season and 20–40% in the rainy season) and fewer changes in the outer area

MỘT SỐ KẾT QUẢ NGHIÊN CỨU BƯỚC ĐẦU VỀ ĐỘNG LỰC TRẦM TÍCH LƠ LỬNG TRONG MÙA LŨ TẠI VÙNG BIỂN VEN BỜ CỬA SÔNG HẬU

Land-ocean interactions in the coastal zone are severely influenced by tidal processces. In regions of high sediment discharge like the coast of Hau river estuary, these processes are even more significant when we analyse data in flood season (September) - which belongs to Agreement of Cooperation in Science and Technology between Vietnam and US (2013-2015) and project VAST-DLT.06/15-16 (2015-2016). Our goal is to investigate the sedimentation  processes. Additionally, we investigated the influence of the tidal currents in relation to the suspended sediment. Salinity (PSU - Practical salinity unit), suspended sediment concentration (NTU - Nephelometric Turbidity Units) were measured by Compac-CTD (Depth temperature conductivity chlorophyll turbidity) and OBS-3A (Turbidity and Temperature Monitoring System) instruments. The results show that the suspended sediment concentration (SSC) correlate with tidal current velocities. The tidal current velocities are up to 60 cm/s near the surface and 40 cm/s near the bottom, increasing SSC in the water column at bottom layer (24 NTU) and decreasing SSC at surface layer (8 NTU). Processes of sediment transport and deposition in flood tide in flood season are influenced by tidal currents more significantly than those in dry season. This leads to an asymmetry of the tidal ellipses and the different deposition between seasons. The analytical results imply the influence of tide and tidal currents on SSC in the coast of Hau river estuary, hence, the spread, sea water and fresh water mixing processes have difference during tidal phases and seasons.Các mối tương tác biển - đất liền trong vùng ven bờ bị chi phối chủ yếu bởi các quá trình thủy động lực như sóng, dòng chảy, lưu lượng nước sông, thủy triều trong đó thủy triều đóng vai trò quan trọng. Tại các khu vực có lưu lượng phù sa lớn như vùng ven biển sông Hậu, các quá trình này càng trở nên rõ rệt khi phân tích từ số liệu khảo sát trong thời kỳ mùa lũ (tháng 9) thuộc chương trình hợp tác khoa học và công nghệ giữa Việt Nam và Hoa Kỳ (2013 - 2015) và đề tài độc lập mã số VAST-ĐLT.06/15-16 (2015 - 2016). Trong chuyến khảo sát này, mục đích là điều tra sự lắng đọng và phân bố theo không gian, thời gian của hàm lượng trầm tích lơ lửng. Ngoài ra, chúng tôi còn khảo sát ảnh hưởng của dòng triều trong mối tương quan với hàm lượng trầm tích lơ lửng. Độ muối (đơn vị PSU - Practical Salinity Unit), hàm lượng trầm tích lơ lửng (đơn vị đo NTU - Nephelometric Turbidity Units) được đo bằng thiết bị Compac-CTD (Depth temperature conductivity chlorophyll turbidity), và thiết bị đo độ đục OBS-3A (Turbidity and Temperature Monitoring System). Kết quả nghiên cứu cho thấy hàm lượng trầm tích lơ lửng tương quan với vận tốc dòng chảy. Tốc độ dòng chảy khi triều lên đến 60 cm/s ở lớp mặt và 40 cm/s ở đáy tạo nên sự tăng nồng độ trầm tích lơ lửng trong cột nước ở tầng đáy 24 NTU và 8 NTU tại tầng mặt. Trong pha triều lên, quá trình vận chuyển và lắng đọng trầm tích lơ lửng bị chi phối bởi dòng triều dài hơn so với mùa khô. Điều này cho thấy sự bất đối xứng của elip thủy triều và dẫn đến sự lắng đọng trầm tích lơ lửng trong các mùa là khác nhau. Từ kết quả phân tích có thể thấy vùng biển ven bờ cửa sông Hậu, hàm lượng trầm tích lơ lửng chịu sự chi phối bởi dòng chảy triều và thủy triều là rất lớn, do đó quá trình lan truyền, xáo trộn nước sông và biển có sự khác biệt đáng kể trong các điều kiện triều và điều kiện mùa

Communication activities of students with the social cultural environment during floods: A case study in Thua Thien Hue province, Vietnam

This study   aims to explore the variances in communication behaviours among undergraduate students within the social-cultural context.  A total of 104 participants (40 lecturers and six managers) were selected from two universities, namely Hue University of Science and Hue University of Education. The collected data was subsequently evaluated. The findings suggest that there are   slight differences between male and female students. This   study highlights significant differences in involvement among Kinh ethnic students   and students from other ethnic groups. Furthermore, the geographical location and sociocultural environment of a region significantly influence the communication behaviors and preferences of students. Students demonstrate higher mean scores in diverse communication activities as compared to lecturers. The results highlight the significance of gender, ethnicity, geographic location   and student status in influencing students' participation in communication. Recognizing and addressing these differences can help in the development of effective communication strategies, the development of inclusive environments   and the encouragement of positive social interactions among various groups of students.  The implications for students' well-being, academic success and intercultural competency might be explored in more detail in further studies by examining the fundamental variables that lead to these differences

Impact of sand mining on sediment transport and morphological change of Hai Phong coastal area

The paper presents the results of simulating the impact of sand mining on sediment transport and morphological change in Hai Phong coastal area based on Delft3D model. Scenario groups are established: Present scenarios without sand mining and simulated scenarios of the present sand mining (assuming 30% sand compared to plan). The scenario groups are calculated in the dry and rainy seasons for main wind directions (NE, SE, SW) in the case of moderate wind and strong wind. The results show that sand mining reduces sediment flow alongshore (2–81%) and seawards (5–83%). Besides, the increase in depth causes morphological change in this area: Rising the deposition rate (5–10 mm/month) at the sand mining locations; decreasing accretion rate and increasing the erosion rate in the neighboring areas of sand mining location

Determinants of antibiotic prescribing in primary care in Vietnam: a qualitative study using the Theoretical Domains Framework

Background: To formulate effective strategies for antimicrobial stewardship (AMS) in primary care, it is crucial to gain a thorough understanding of factors influencing prescribers' behavior within the context. This qualitative study utilizes the Theoretical Domains Framework (TDF) to uncover these influential factors. Methods: We conducted a qualitative study using in-depth interviews and focus group discussions with primary care workers in two provinces in rural Vietnam. Data analysis employed a combined inductive and deductive approach, with the deductive aspect grounded in the TDF. Results: Thirty-eight doctors, doctor associates, and pharmacists participated in twenty-two interviews and two focus group discussions. We identified sixteen themes, directly mapping onto seven TDF domains: knowledge, skills, behavioral regulation, environmental context and resources, social influences, social/professional role and identity, and optimism. Factors driving unnecessary prescription of antibiotics include low awareness of antimicrobial resistance (AMR), diagnostic uncertainty, prescription-based reimbursement policy, inadequate medication supplies, insufficient financing, patients’ perception of health insurance medication as an entitlement, and maintaining doctor-patient relationships. Potential factors facilitating AMS activities include time availability for in-person patient consultation, experience in health communication, and willingness to take action against AMR. Conclusion: Utilizing the TDF to systematically analyze and present behavioral determinants offers a structured foundation for designing impactful AMS interventions in primary care. The findings underscore the importance of not only enhancing knowledge and skills but also implementing environmental restructuring, regulation, and enablement measures to effectively tackle unnecessary antibiotic prescribing in this context

Impact assessment of a local seventeen-year initiative on cassava-based soil conservation measure on sloping land as a climate-smart agriculture practice in Van Yen District, Yen Bai Province, Vietnam

Van Yen District in Yen Bai Province represents the general terrain conditions and farming systems of the northern mountainous region of Vietnam. It has suffered land degradation due to soil erosion and nutrient depletion, which in turn led to declined crop yield, and food insecurity. The district experienced these impacts due to unsustainable upland agricultural practices. The Department of Agriculture and Rural Development realized that their previous practices would not leave anything behind for the next generations. This prompted them to launch an agricultural conservation program in 2003 to restore degraded soils, which would improve the production in the farms, and diversify incomes and the household economy of local farmers. Over the 17 years of implementation, the program has introduced six conservation measures that have been well-received and implemented by the farmers of Van Yen. This report assesses the impacts of the 17-year program using the economic, environmental, and social lenses with a focus on the cassava crop, considering the traditional cassava monocrop system (or non-adoption group) and the six conservation measures (or adoption group). The study applied a mixed-methods approach, using semi-questionnaire to collect qualitative information from 488 farmers across six communes and surveys to collect soil samples to assess the levels of soil restoration among certain measures. The study also used the quantitative research findings from two other research studies conducted in Mau Dong Commune to help discuss its findings

Conservation agriculture for a climate-resilient and sustainable upland agriculture: A success story from a seventeen-year local program in northern Vietnam

The brief elaborates on the lessons learned from an impact assessment of a local seventeen-year initiative on cassava-based soil conservation measure on sloping land as a climate-smart agriculture practice in Van Yen District, Yen Bai Province, Vietnam. Focusing on the economic, environmental, and social benefits, the recommendations push for institutional level strategies on how this success story can be replicated in areas with similar biophysical and socio-economic conditions

Barriers and enablers to blood culture sampling in Indonesia, Thailand and Viet Nam: a Theoretical Domains Framework-based survey

Objective Blood culture (BC) sampling is recommended for all suspected sepsis patients prior to antibiotic administration. We examine barriers and enablers to BC sampling in three Southeast Asian countries. Design A Theoretical Domains Framework (TDF)-based survey, comprising a case scenario of a patient presenting with community-acquired sepsis and all 14 TDF domains of barriers/enablers to BC sampling. Setting Hospitals in Indonesia, Thailand and Viet Nam, December 2021 to 30 April 2022. Participants 1070 medical doctors and 238 final-year medical students were participated in this study. Half of the respondents were women (n=680, 52%) and most worked in governmental hospitals (n=980, 75.4%). Outcome measures Barriers and enablers to BC sampling. Results The proportion of respondents who answered that they would definitely take BC in the case scenario was highest at 89.8% (273/304) in Thailand, followed by 50.5% (252/499) in Viet Nam and 31.3% (157/501) in Indonesia (p<0.001). Barriers/enablers in nine TDF domains were considered key in influencing BC sampling, including ‘priority of BC (TDF-goals)’, ‘perception about their role to order or initiate an order for BC (TDF-social professional role and identity)’, ‘perception that BC is helpful (TDF-beliefs about consequences)’, ‘intention to follow guidelines (TDF-intention)’, ‘awareness of guidelines (TDF-knowledge)’, ‘norms of BC sampling (TDF-social influence)’, ‘consequences that discourage BC sampling (TDF-reinforcement)’, ‘perceived cost-effectiveness of BC (TDF-environmental context and resources)’ and ‘regulation on cost reimbursement (TDF-behavioural regulation)’. There was substantial heterogeneity between the countries. In most domains, the lower (higher) proportion of Thai respondents experienced the barriers (enablers) compared with that of Indonesian and Vietnamese respondents. A range of suggested intervention types and policy options was identified. Conclusions Barriers and enablers to BC sampling are varied and heterogenous. Cost-related barriers are more common in more resource-limited countries, while many barriers are not directly related to cost. Context-specific multifaceted interventions at both hospital and policy levels are required to improve diagnostic stewardship practices