232 research outputs found
SEWER DISCHARGE CHARACTERISTICS AND WATER BALANCE IN DRY SEASON IN HUE, VIETNAM
Vietnam has been developing sewerage recently. Although sewer discharge quantity and quality data is vital for proper sewage management, their fluctuation has not been well characterized in most of cities in developing countries. This study aimed to characterize a combined sewer discharge in a residential drainage area (11.2 ha) in Hue city, Vietnam on dry days in dry season (DdDs). A 24-hour survey on sewage quantity and quality was conducted at the sewer outlet on two weekdays and two weekends in July 2015. Household water consumption was hourly recorded from water meters for 23 households. Then results of discharge characteristics were compared with those on dry days in rainy season (DdRs) of our previous study. Results showed that hourly variations of flow rate corresponded to the water consumption trend. Average discharge flow rate was equivalent to 38.5 ± 4.4 L/cap/day, which was much lower than that on DdRs (64.2 ± 25.0 L/cap/day). In contrast, pollutant concentrations on DdDs were higher than those on DdRs and fluctuated slightly in a day and among days in a week. Low concentrations of discharge in both dry season and rainy season showed that domestic wastewater in urban Hue was not strongly polluted in terms of organic matter and nutrients. Sewer water balance showed that only 29 % of total water inputted to the sewer system was discharged through the outlet on DdDs, while the remaining 71 % was likely exfiltrated to the ground from the sewer system, which will be a potential pollution source to soil and groundwater
Challenges And Opportunities For The Development Of Infrastructure After ‘Oda Graduation’ - Moving Towards Sustainable Development: Case Study Of Vietnam
The research on ODA will be focused on its relation to Goal 17, the Partnership, considered a major issue by the researchers, especially in the case of Vietnam as a developing economy. ODA was mainly used for investing in economic infrastructure when Vietnam witnessed a downfall in receiving financial aid due to its significant economic growth. ODA helped Vietnam transform from one of the world’s poorest nations into a lower middle-income country and soon, this is going to lead to the ‘ODA Graduation’. However, the process has just begun. The country is still in a process of industrialization and modernization and its socio-economic situation has not been stable or solid. By all means, ODA is not only a financial resource, it also helps the country to accomplish Sustainable Development Goals (SDGs) of the UN. ‘ODA Graduation’ means that the economy of Vietnam has faced certain challenges such as increasing pressure of outbound debts; raising impact on social development or imbalance between high capital recovery investments and public-services investments. However, ‘ODA Graduation’ has brought certain opportunities such as increasing Vietnam’s independence in capital mobilization, preventing the removal of tariffs barrier, reducing losses and waste of funds. This research gives recommendations for improving Vietnam’s economic situation and can help overcome the difficulties in the period of ‘ODA Graduation’
Challenges And Opportunities For The Development Of Infrastructure After ‘Oda Graduation’ - Moving Towards Sustainable Development: Case Study Of Vietnam
The research on ODA will be focused on its relation to Goal 17, the Partnership, considered a major issue by the researchers, especially in the case of Vietnam as a developing economy. ODA was mainly used for investing in economic infrastructure when Vietnam witnessed a downfall in receiving financial aid due to its significant economic growth. ODA helped Vietnam transform from one of the world’s poorest nations into a lower middle-income country and soon, this is going to lead to the ‘ODA Graduation’. However, the process has just begun. The country is still in a process of industrialization and modernization and its socio-economic situation has not been stable or solid. By all means, ODA is not only a financial resource, it also helps the country to accomplish Sustainable Development Goals (SDGs) of the UN. ‘ODA Graduation’ means that the economy of Vietnam has faced certain challenges such as increasing pressure of outbound debts; raising impact on social development or imbalance between high capital recovery investments and public-services investments. However, ‘ODA Graduation’ has brought certain opportunities such as increasing Vietnam’s independence in capital mobilization, preventing the removal of tariffs barrier, reducing losses and waste of funds. This research gives recommendations for improving Vietnam’s economic situation and can help overcome the difficulties in the period of ‘ODA Graduation’
Level of Factors impact on the Buyers’ Intention in Buying Private Health Insurance with the Case of Vietnam Non-Life Insurance Companies
The study aims to determine the influence of factors affecting the intention to purchase private health insurance at non-life insurance companies in Vietnam. The samples were surveyed from 500 people from many areas but mostly in Hanoi. The study identified and clarified 5 independent factors affecting the intention to buy private health insurance at non-life health insurance companies in Vietnam. The analysis results show 5 variables: "Past experience", "Perception of service quality of insurance companies", "Perceived behavioral control", "Attitude towards risks and private health insurance ", and the variable "Subjective norms on private health insurance" affect people's intention to buy private health insurance. Several policies have been proposed to increase customers' intention to buy private health insurance at non-life insurance companies from the analysis. To raise customer's intention to purchase private health insurance, the research team recommends non-life insurance company to improve service quality, especially after-sales service, the quality and expertise of staff, and the government to complete policies and legal framework on private health insurance. Moreover, the research team also recommend to renovate the quality of organizing the private health insurance regime and form the basis of the entire population pathology record. Keywords: private health insurance, intention to purchase, non-life insurance company. DOI: 10.7176/EJBM/12-27-06 Publication date:September 30th 202
GENERATION OF BACILLUS SUBTILIS CLONE DISPLAYING METAL-BINDING POLYHISTIDYL PEPTIDE
Joint Research on Environmental Science and Technology for the Eart
Effects of protein levels of commercial diets on the growth performance and survival rate of rabbitfish (Siganus guttatus) at the nursing stage
This study aimed to determine the effect of a commercial diet's protein level on the fry-to-fingerling stage. Thirty days-old fries having the initial length and weight of 18.25 ± 0.15 mm fish-1 and 0.036 ± 0.50 g fish-1 respectively have been used in this study. Diet having three protein levels i.e. 30% (trial 1 as control), 35% (trial 2), 40% (trial 3), and 45% (trial 4), respectively, have been used to evaluate the effect of protein, and each trial has been repeated three times. During the study, stocking density was allocated to 1000 fish per composite tank with a volume of 1 m3. After 30 days of rearing, the weight of fingerlings in trial 1 reached up to 1.50 ± 0.02 g fish-1 and it was recorded as 1.52 ± 0.01g for trial 2, these two were lower than that of trials 3 and 4, where fingerling weight was reported 1.69 ± 0.01 and 1.58g fish-1 respectively and obtained the best weight compared to others. The length of fingerlings at the end of the experimental period was also changed in different trials and it was recorded 47.12; 46.92; 50.97; and 48.89 mm fish-1 for trail 1, 2, 3, and 4 respectively, among the tested combinations lower fingerlings length was recorded for trial 2 (35% CP), but it is not significantly different for trial 1 and 2 and a significant difference (P < 0.05) was reported for trail 2, 3, and 4. The survival rate of fingerlings ranged from 67.27 to 72.33%. Meanwhile, the herd distribution coefficient variation (CVW) in the treatment using 40% protein (trial 3) was the highest at 72.33% (p < 0.05). The results of the study can be concluded that the level of protein has a significant effect on the various growth parameters of fingerlings
Species diversity of rotifers (Rotifera: Eurotatoria) of Phu Ninh Lake with five new records from Vietnam
A total of sixty-one taxa of rotifer, belonging to 15 families, 3 orders were identified from the Phu Ninh Lake, Vietnam. Of these, five species were recorded new to Vietnam Rotifera fauna, including Lecane acanthinula (Hauer, 1938), L. sola (Hauer, 1936), L. thailandensis Segers & Sanoamuang, 1994, L. pyriformis (Daday, 1905), and Mytilina bisulcata (Lucks, 1912). The result raised the total number of rotifers known from Vietnam to 227 species. Moreover, the results showed that the number of species recorded increased with the increase of sample size, which followed the equation y=12.85+14.12log(x) (R2 = 0.99). Based on the estimators, the α-diversity of rotifers in Phu Ninh Lake might be up to 67±4 taxa (according to the Bootstrap index), 71±8 taxa (according to the Chao index), or even up to 79 taxa (according to Jacknife 2 index)
ẢNH HƯỞNG CỦA PROTEIN LvCTL3 TÁI TỔ HỢP LÊN CHỈ TIÊU MIỄN DỊCH, TĂNG TRƯỞNG VÀ KHẢ NĂNG KHÁNG BỆNH AHPND TRÊN TÔM THẺ CHÂN TRẮNG (Litopenaeus vannamei) DO Vibrio parahaemolyticus
Whiteleg shrimp (size of 0.55 ± 0.1 g) were fed basic diets either without or with supplementation of recombinant LvCTL3 protein at concentrations of 100; 200 and 500 µg/mL equivalent to 2; 4 and 10 mg/kg. After a 30-day feeding trial, shrimp were collected to measure growth parameters and survival rate, and shrimp hemolymph was also collected for analysis of immune parameters. Then, the shrimp were challenged with Vibrio parahaemolyticus at a concentration of 1 105 CFU/mL for 15-day. The results indicated that the growth performance, feed conversion ratio, immune parameters such as total hemocyte count, phenoloxidase, superoxide dismutase, lysozyme enzyme activity, and phagocytic activity of shrimp in the treated groups were significantly higher than those in the control (p < 0.05). Specifically, the dietary supplementation with recombinant LvCTL3 protein at 4 or 10 mg/kg showed better results than the other treatments. After a 15-day bacterial challenged test, the cumulative mortality rate of shrimp in the treated ranged from 20.0 to 36.67% which was significantly lower than that of the control group (63.66%) (p < 0.05).Tôm thẻ chân trắng có khối lượng 0,55 ± 0,1 g/con được cho ăn với khẩu phần cơ bản có hoặc không bổ sung protein LvCTL3 tái tổ hợp với các nồng độ lần lượt 100; 200 và 500 µg/mL tương ứng với hàm lượng 2; 4 và 10 mg/kg thức ăn. Sau 30 ngày thí nghiệm tôm được thu thập để xác định các chỉ tiêu tăng trưởng, tỷ lệ sống và máu tôm được lấy để phân tích các chỉ tiêu miễn dịch. Sau đó, tôm được thí nghiệm cảm nhiễm với vi khuẩn V. parahaemolyticus (nồng độ 1 105 CFU/mL). Kết quả các chỉ tiêu tăng trưởng, hệ số chuyển đổi thức ăn và các chỉ tiêu miễn dịch: tổng số tế bào máu, hoạt tính các enzyme: phenoloxidase, Superoxide dismutase (SOD), lysozyme và hoạt động thực bào của máu tôm ở các nghiệm thức thí nghiệm ăn thức ăn có bổ sung protein LvCTL3 tái tổ hợp cao hơn đáng kể so với đối chứng (p < 0,05). Trong đó, tôm được cho ăn chế độ ăn có bổ sung 4 hoặc 10 mg/kg thức ăn có tổng số tế bào máu và SOD được ghi nhận cao hơn so với các nghiệm thức còn lại. Sau 15 ngày cảm nhiễm, tỷ lệ chết tích lũy của tôm ở các nghiệm thức từ 20,0–36,67%, là thấp hơn đáng kể so với đối chứng (63,66%).
Evaluation Of Allelopathic Potential Of Cissus sicyoides Against the Growth Of Echinochloa Crus-Galli And Some Tested Plants
Many plant species in nature exert significant allelopathic potential as part of the defense mechanism system, many among their secondary metabolites (allelochemicals), including mineral constituents, which are responsible for the suppression of weeds and enhancing crop yield when directly incorporated into paddy fields. Cissus sicyoides is considered a high-potential allelopathic plant because of its invasion in nature and detected allelochemicals from the plant parts in some studies. The objective of this research was to exploit the allelopathic properties of C.sicyoides against paddy weeds and some indicator plants under laboratory bioassays and greenhouse conditions. The results demonstrated that C. sicyoides had significant inhibition on E. crus-galli, tested plants, and other paddy weeds. In the laboratory conditions, the extracts from C.sicyoides leaves inhibited the growth of Echinochloa crus-galli by 54.3%. The powders from C.sicyoides leaves inhibited the emergence of paddy weeds by approximately 100.0%. In the greenhouse conditions, the powders from C.sicyoides leaves by adding after 3 and 13 days inhibited the growth of E. crus-galli and the emergence of paddy weeds by 64.4%. Remarkably, negligible harmful effects on rice growth were observed. The findings of the study may provide useful information for the exploitation of this plant species to effectively control weeds in the rice fields for sustainable agriculture production
Lecane (Rotifera: Lecanidae) community in psammon habitat in Central Coast Vietnam: Diversity and relation to environmental condition
Characteristics of the Lecane (Rotifera) community in psammon in Central Coast Vietnam were investigated. A total of 50 taxa were identified in samples collected at hygropsammon zones of temporary pools, contributing 4 new species to rotifers' record of Vietnam. Psammonxenic species accounted for the largest percentage of Lecane community with 82%, followed by psammophiles (12%) and psammonbionts (6%). Influences of some environmental factors on the distribution of psammic lecanids were also observed. This group of organisms showed a slight tendency towards sand with grain sizes larger than 125 µm. Besides, other abiotic factors including pH, total phosphorus (TP) and total dissolved solids (TDS) were also found to significantly related to the distribution of some common Lecane species
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