MANAGEMENT OF TEACHING ENGLISH ACTIVITIES OF GRADE 10 OF HIGH SCHOOLS IN NINH KIEU DISTRICT, CAN THO CITY, VIETNAM

Managing English teaching activities for Grade 10 in high schools is one of the most important tasks and activities because it plays a decisive role in the success of teaching and the improvement of teaching quality for Grade 10 in high schools. This activity shows not only the results and quality of the students’ study but also the education management of managers and teaching activities of teachers in Ninh Kieu District, Can Tho City, Vietnam. The study was conducted at 4 high schools in Ninh Kieu District, Can Tho City, namely Phan Ngoc Hien High School, Chau Van Liem High School, An Khanh High School, and Nguyen Viet Hong High School. Participants in the survey by questionnaires were school managers (n = 4), English teachers (n = 17) and 10th Graders (n = 456). And the findings showed that to achieve the desired effect in the management of teaching activities of 10th Grade English at a high school in Ninh Kieu District, Can Tho City, the administrator or the school leader needs to have appropriate management measures and implement those measures in a synchronous and unified manner. Besides, through the use of measures, school leaders can recognize the positive aspects as well as the limitations of the situation. From there, management staff can continue to promote strengths and overcome existing weaknesses and limitations, and make adjustments in a timely manner. Some measures can be mentioned as follows: organizing activities to raise awareness about the importance of teaching 10th Grade English; organizing professional and professional training activities for 10th Grade English teachers; strengthening the management of the content and curriculum development of 10th Grade English subjects; directing the renewal of teaching methods and forms of organization of teaching activities in Grade 10 English; directing the renewal of forms and methods of studying English for 10th Grade students; directing the renewal of the form of examination and assessment of students' learning results in English 10; strengthening facilities and equipment to serve the teaching of 10th Grade English in high schools.  Article visualizations

Development of Daphnia magna under exposure to the xenobiotic octylphenol: Research article

Xenobiotics are of human and environmental concerns due to their potential toxicity. Octylphenol is one of the very common and daily used xenobiotics in door and out door activities of human beings. Toxicity of octylphenol to aquatic organisms, especially to zooplankton (e.g. Daphnia magna) was investigated but not fully understood. In this study we evaluated the chronic effects of octylphenol at the concentrations of 5, 50 and 500 μg L-1 on Daphnia magna over a period of 14 days. The results showed that low concentration of octylphenol (5 μg L-1) stimulated the maturation while high concentrations of the chemical (50 and 500 μg L-1) caused a significant mortality to the Daphnia. Besides, all the tested concentrations of octylphenol had serious impacts on fecundity and growth of the animals. Investigations on the presence, distribution, fate and toxicity of xonobiotics including octylphenol in the developing country environment are suggested for human, environmental and ecological health protection.Những hợp chất tổng hợp đang là mối quan ngại cho con người và môi trường vì khả năng gây độc của chúng. Octylphenol là một trong những hợp chất tổng hợp được sử dụng phổ biến và thường xuyên trong những hoạt động của con người trong nhà và ngoài trời. Độc tính của octylphenol đối với thủy sinh vật, đặc biệt đối với động vật phù du (vd. Daphnia magna) mặc dù đã được nghiên cứu nhưng vẫn chưa được hiểu biết đầy đủ. Trong nghiên cứu này, chúng tôi đánh giá ảnh hưởng mãn tính của octylphenol ở các nồng độ 5, 50 và 500 μg/lít lên Daphnia magna trong thời gian 14 ngày. Kết quả cho thấy ở nồng độ octylphenol thấp (5 μg/lít) kích thích sự thành thục của sinh vật trong khi ở nồng độ cao hơn (50 và 500 μg/lít) gây chết đáng kể Daphnia. Bên cạnh đó, tất cả các nồng độ ocytlphenol dùng trong thí nghiệm gây ảnh hưởng nghiêm trọng lên sức sinh sản và sinh trưởng của sinh vật. Nghiên cứu về sự hiện diện, phân bố, phát tán và độc tính của những chất tổng hợp bao gồm octylphenol ở các nước đang phát triển nên được tiến hành vì mục tiêu bảo vệ sức khỏe con người, môi trường và hệ sinh thái

A Methodology to Characterize Riverine Macroplastic Emission Into the Ocean

Land-based macroplastic is considered one of the major sources of marine plastic debris. However, estimations of plastic emission from rivers into the oceans remain scarce and uncertain, mainly due to a severe lack of standardized observations. To properly assess global plastic fluxes, detailed information on spatiotemporal variation in river plastic quantities and composition are urgently needed. In this paper, we present a new methodology to characterize riverine macroplastic dynamics. The proposed methodology was applied to estimate the plastic emission from the Saigon River, Vietnam. During a 2-week period, hourly cross-sectional profiles of plastic transport were made across the river width. Simultaneously, sub-hourly samples were taken to determine the weight, size and composition of riverine macroplastics (>5 cm). Finally, extrapolation of the observations based on available hydrological data yielded new estimates of daily, monthly and annual macroplastic emission into the ocean. Our results suggest that plastic emissions from the Saigon River are up to four times higher than previously estimated. Importantly, our flexible methodology can be adapted to local hydrological circumstances and data availability, thus enabling a consistent characterization of macroplastic dynamics in rivers worldwide. Such data will provide crucial knowledge for the optimization of future mediation and recycling efforts

What's in the water? – Target and suspect screening of contaminants of emerging concern in raw water and drinking water from Europe and Asia

There is growing worry that drinking water can be affected by contaminants of emerging concern (CECs), potentially threatening human health. In this study, a wide range of CECs ( n = 177), including pharmaceuticals, pesticides, perfluoroalkyl substances (PFASs) and other compounds, were analysed in raw water and in drinking water collected from drinking water treatment plants (DWTPs) in Europe and Asia ( n = 13). The impact of human activities was reflected in large numbers of compounds detected ( n = 115) and high variation in concentrations in the raw water (range 15-7995 ng L & minus;1 for E177 CECs). The variation was less pronounced in drinking water, with total concentration ranging from 35 to 919 ng L & minus;1 . Treatment efficiency was on average 65 +/- 28%, with wide variation between different DWTPs. The DWTP with the highest ECEC concentrations in raw water had the most efficient treatment procedure (average treatment efficiency 89%), whereas the DWTP with the lowest E177 CEC concentration in the raw water had the lowest average treatment efficiency (2.3%). Suspect screening was performed for 500 compounds ranked high as chemicals of concern for drinking water, using a prioritisation tool (SusTool). Overall, 208 features of interest were discovered and three were confirmed with reference standards. There was co-variation between removal efficiency in DWTPs for the target compounds and the suspected features detected using suspect screening, implying that removal of known contaminants can be used to predict overall removal of potential CECs for drinking water production. Our results can be of high value for DWTPs around the globe in their planning for future treatment strategies to meet the increasing concern about human ex-posure to unknown CECs present in their drinking water.(c) 2021 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/

Study on treatment performance of low cost membrane based septic tank at various fluxes

The objective of this study was to evaluate the performance and fouling behavior of membrane based septic tank (MBST).Woven Fiber Microfiltration (WFMF) introduced in the chamber of a septic tank as a submerged membrane for domestic wastewater treatment. Concentrations of black water stored in the third chamber were 125 ± 15 mg/L COD, 124 ± 28 mg/L SS and 59 ± 9 mg/L TKN. Results showed that COD removal was 54-78 % of which effluent achieved less than 50 mg/L. In addition, the withdrawal was mostly non-performed suspended solids. TMP level increased gradually, indicated low membrane fouling rate (dTMP/dt) of 0.4-1.0 kPa/day at flux as low as 2.5 LMH. While at the flux greater than 3.4 LMH the fouling rate increased rapidly with the fouling rate of 13 kPa/day

Bioaccumulation of trace elements in the hard clam, Meretrix lyrata, reared downstream of a developing megacity, the Saigon-Dongnai River Estuary, Vietnam

International audienceA large number of white hard clam farms are in the estuary shoreline of Saigon-Dongnai Rivers, which flow through Ho Chi Minh City, a megacity, and numerous industrial zones in the basin catchment area. In this study, eleven trace elements (Mn, Fe, Co, Ni, Cu, Zn, As, Se, Cd, Hg, and Pb) in the hard clam Meretrix lyrata and its habitats including surface water, suspended particulate matter, and sediment were evaluated to understand the bioaccumulation of trace metals from the environment into the whole tissues of the hard clam as well as its different organs. The samples were collected monthly in dry, transition, and wet seasons of the southern part of Vietnam from March to September 2016. The results showed that seasonal and spatial variations of the studied metal concentrations in the hard clam M. lyrata might be influenced by the sea current as well as the surface runoff in the rainy season. The relationship between condition index and the element concentrations in M. lyrata might be affected by the living environment conditions and farming methods. In addition, the hazard index values of all trace elements in the hard clam M. lyrata harvested in the sampling time show that the hard clams farmed in the study area were safe for local consumers

Exploration of a cost-effective draw solution based on mixing surfactant and sodium chloride for forward osmosis desalination process

International audienc

Spatial variation and risk assessment of trace metals in water and sediment of the Mekong Delta

International audienceThe Mekong Delta, is home to 17 million inhabitants and faces numerous challenges relating to climate change, environmental degradation and water issues. In this study, we assess trace metals concentrations (Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Mo, Cd, Hg, Pb) in the water, suspended particulate matter and surface sediments of the Tien River, the Northern branch of the Mekong Delta, during both dry and rainy seasons. Metal concentrations in the dissolved and suspended particle phases remain in the low concentration range of the main Asian Tropical River. During transportation in the riverine part, we evidenced that V, Cr, Co, As and Pb are dominant in the particulate phase while Mo, Ni and Cu dominate in the dissolved fraction. In the salinity gradient, dissolved U, V, Mo exhibit conservative behaviour while Ni, Cu, As, Co and Cd showed additive behaviour suggesting desorption processes. In the surface sediment, metal concentrations are controlled by the particle-size, POC contents and Fe, Al and Mn e oxy(hydr)oxides. Calculated Enrichment Factor and Geoaccumulation Index evidenced As enrichment while the calculated mean effect range median quotients evidenced a low to medium ecotoxicological potential effects range in the surface sediments