POTENTIAL INTOXICATION BY TOXIC CYANOBACTERIA AND THEIR TOXINS IN SOME VIETNAMESE FRESH WATERBODIES

Joint Research on Environmental Science and Technology for the Eart

RESPONSES AND STRUCTURAL RECOVERY OF PERIPHYTIC DIATOM COMMUNITIES AFTER SHORT-TERM ENVIRONMENTAL DISTURBANCE IN SOME RIVERS (HANOI, VIETNAM)

Joint Research on Environmental Science and Technology for the Eart

PURIFICATION OF PHOSPHOGYPSUM FOR USE AS CEMENT RETARDER BY SULPHURIC ACID TREATMENT

Phosphogypsum is a by-product of the wet phosphoric acid production. In this study, chemical compositions of phosphogypsum waste (PG) in Hai Phong diammonium phosphate plant (DAP1) and Lao Cai diammonium phosphate plant (DAP2) in Vietnam were surveyed for the purpose of gypsum recovery by P2O5, F removal to meet TCVN11833 for use treated gypsum as cement retarder. Studies of impurities P2O5, F, TOC removal by sulfuric acid 10 % at 28 0C was presented. The results found that the combination of a low concentration of sulfuric acid treatment, washing, lime neutralizing, and thermal treatment was successful in Phoshogypsum treatment for use as cement retarder. The cement test proved that treated PG could partially replace natural gypsum as a retarder.Keywords:  phosphogypsum treatment, phosphorus pentoxide removal, calcium sulfate transition phase, cement retarder.

Phytoremediation of heavy metal polluted soil and water in Vietnam

Phytoremediation has been intensively studied during the past decade due to its cost-effectiveness and environmental harmonies. Most of the studies on treatment of heavy metal pollution in soil and water by plant species have been done in developed countries but are limited in Vietnam. In this study, we presented some research results of phytoremediation of polluted soils and water with heavy metals that were done by Institute of Environmental Technology for several last years. For treatment of heavy metal pollution in the water, some plants have great ability to accumulate heavy metals such as Vetiveria zizanioides, Phragmites australis, Eichhornia crassipes, Pistia stratiotes, Ipomoea aquatica, Nypa fruticans and Enhydra fluctuans. The heavy metal uptake into shoots and roots of 33 indigenous plant species in Thai Nguyen province was also determined. Two species of the plants investigated, Pteris vittata L. and Pityrogramma calomelanos L. were As hyperaccumulators, containing more than 0.1% As in their shoots while Eleusine indica, Cynodon dactylon, Cyperus rotundus and Equisetum ramosissimum accumulated very high Pb (0.15-0.65%) and Zn (0.22-1.56%) concentrations in their roots. Some experiments to clarify the potential of several plants as good candidates for phytoremediation of polluted soil by heavy metals were carried out in our institute.Phương pháp sử dụng thực vật để xử lý ô nhiễm đã được nghiên cứu nhiều trong thập kỷ qua do chi phí thấp và thân thiện với môi trường. Hầu hết các nghiên cứu về xử lý ô nhiễm kim loại nặng trong đất và nước bằng thực vật đã được thực hiện ở các nước phát triển nhưng ít có tại Việt Nam. Trong nghiên cứu này, chúng tôi giới thiệu một số kết quả dùng công nghệ thực vật để xử lý ô nhiễm kim loại nặng trong đất và nước tại Viện Công nghệ môi trường trong những năm gần đây. Dối với xử lý ô nhiễm kim loại nặng trong nước, một số thực vật có khả năng tích lũy tốt kim loại nặng như Vetiveria zizanioides, Phragmites australis, Eichhornia crassipes, Pistia stratiotes, Ipomoea aquatica, Nypa fruticans và Enhydra fluctuans. Sự hấp thụ và tích lũy kim loại nặng trong phần trên mặt đất và rễ của 33 loài thực vật bản địa tại Thái Nguyên cũng đã được xác định. Hai loài thực vật khảo sát là Pteris vittata và Pityrogramma calomelanos là những loài siêu tích lũy As, chứa hơn 0,1% As trong phần trên mặt đất của cây. leusine indica, Cynodon dactylon, Cyperus rotundus và Equisetum ramosissimum tích lũy Pb (0,15-0,65%) và Zn (0,22-1,56%) rất cao trong rễ. Một số thí nghiệm đánh giá tiềm năng của một số thực vật là đối tượng tốt cho xử lý ô nhiễm kim loại nặng trong đất đã được tiến hành trong phòng thí nghiệm của Viện Công nghệ môi trường

Влияние комбинированного применения гипоксическо-гиперкапнического стимула и методов аппаратной физиотерапии на иммунную систему больных хроническим обструктивным заболеванием легких

Изучено влияние на иммунную систему больных хроническим обструктивным заболеванием легких комбинации гипоксическо−гиперкапнического стимула и разных методов аппаратной физиотерапии. Установлено, что в целом комбинированное применение разработанной методики уменьшает дефицит Т−звена и частично восстанавливает работу гуморального компонента иммунитета.The influence of combined use of hypoxic−hypercapnic stimulus and different methods of apparatus physiotherapy on the immune system of the patients with chronic obstructive pulmonary disease was investigated. Combined application of the developed technique was established to diminish T−link deficiency and to restore partially the work of humoral immunity

EGG QUALITY COMPARISON OF TWO VIETNAMESE CHICKEN BREEDS (RI AND MIA)

In the context of the valorization of poultry biodiversity, this work represents a step toward a better knowledge of the production abilities of local chicken breeds in Vietnam. Local chicken breeds are indeed particularly well suited for low-input rearing systems, as widely practiced in rural households of Vietnam. The socio-economic importance of these breeds might be underpinned by a market valorization through the mounting of differentiated quality value chains. Such a strategy needs the production potential of these local breeds to be assessed using parameters of egg quality and quantity. This study presents data about egg quality traits in two chicken breeds, the Ri and the Mia. The former is the most widespread breed in Vietnam, while the latter is known to be in danger of extinction. Nineteen parameters of quality of ninety eggs of Ri chickens and sixty eggs of Mia chickens were measured, each for both 40 and 60-weeks old hens to take hens ages into account.Mean egg weight of Mia eggs (44.70g) was significantly (p<0.001) higher than that of Ri eggs (41.68g). The yolk to albumen ratio was not significantly different (p>0.05) between the two breeds at the age of 40 weeks (Ri: 0.55; Mia: 0.58). For 60-weeks old hens, the ratio became significantly (p<0.05) higher in Mia eggs compared to Ri eggs (0.64 vs. 0.57). No significant difference (p>0.05) was recorded between the two breeds for parameters used for egg freshness assessment (Haugh’s units and pH of albumen and yolk) or eggshell resistance (maximal breakage force). Despite the small sample available for the study (due to the low availability of Mia hens and eggs), significant differences in egg quality traits were thus observed between these two breeds.Peer reviewe

Healthcare use for diarrhoea and dysentery in actual and hypothetical cases, Nha Trang, Viet Nam.

To better understand healthcare use for diarrhoea and dysentery in Nha Trang, Viet Nam, qualitative interviews with community residents and dysentery case studies were conducted. Findings were supplemented by a quantitative survey which asked respondents which healthcare provider their household members would use for diarrhoea or dysentery. A clear pattern of healthcare-seeking behaviours among 433 respondents emerged. More than half of the respondents self-treated initially. Medication for initial treatment was purchased from a pharmacy or with medication stored at home. Traditional home treatments were also widely used. If no improvement occurred or the symptoms were perceived to be severe, individuals would visit a healthcare facility. Private medical practitioners are playing a steadily increasing role in the Vietnamese healthcare system. Less than a quarter of diarrhoea patients initially used government healthcare providers at commune health centres, polyclinics, and hospitals, which are the only sources of data for routine public-health statistics. Given these healthcare-use patterns, reported rates could significantly underestimate the real disease burden of dysentery and diarrhoea