Serological and Molecular Characterization of Avian Metapneumovirus in Chickens in Northern Vietnam.

Avian Metapneumovirus (aMPV) is a causative agent of respiratory disease complex in turkeys and chickens that has recently been detected in Vietnam. Due to its novelty, this study was conducted to elucidate the distribution of aMPV in several provinces in northern Vietnam. By the application of Enzyme-Linked Immunosorbent Assay (ELISA) and nested Reverse Transcription-Polymerase Chain Reaction (RT-PCR), this study demonstrated the circulation of aMPV in 12 out of 14 cities/provinces with positive rates of 37.6% and 17.2%, respectively. All nested RT-PCR positive samples were aMPV subgroup B. By pairing the detection results with age groups, it was observed that aMPV infections occurred in chickens of all ages. Additionally, by genetic characterization, aMPV strains were demonstrated to not be attenuated vaccine viruses and to belong to at least two genetic clades. Overall, the obtained results provided insights into the prevalence of aMPV and indicated a greater complexity of respiratory diseases in chickens in Vietnam.

Ammonium removal from aqueous solutions by fixed-bed column using corncob-based modified biochar.

This study investigated the potential of removing ammonium ([Formula: see text]) from aqueous solutions using corncob based on modified biochar (MBCC) in the fixed-bed column. Corncob biochar was soaked in a mixture of HNO3 6.0 M and NaOH 0.3 M to prepare active binding sites for ammonium removal. The effect of initial ammonium concentrations (10-40 mg/L), flow rates (1-9 mL/min) and MBCC fixed-bed heights (8-24 cm) on the breakthrough characteristics of the adsorption system were studied. The results showed that the highest adsorption capacity of fix-bed column, the breakthrough time and value of Ct/Co were 12.83 mg/g, 480 min and 0.862 ± 0.025 at 10 mg/L of initial ammonium concentration, 8 cm of MBCC fixed-bed height and 3 mL/min of flow rate, respectively. The breakthrough curve model in this study also indicated that all Yoon-Nelson, Thomas and Adam-Bohart models well fit with the experimental data with a high R2. The results also proved that MBCC can be used as a potential adsorbent for eliminating [Formula: see text] in the fixed-bed column. The saturated MBCC was also regenerated and reused consecutively for four cycles. The usage of mixture of NaOH and NaCl in recovering MBCC was better than NaCl only.

Temperature inversion and air pollution relationship, and its effects on human health in Hanoi City, Vietnam.

This study aimed to investigate the effects of temperature inversions on the concentration of some pollutants in the atmosphere in Hanoi City, Vietnam, during the period from 2011 to 2015. This work also aimed to evaluate relationships between the thermal inversion and health effects that are associated with air pollution. During this period, the temperature inversions were most frequently presenting from November to March in Hanoi City. Air quality data was gathered from air quality monitoring stations located in the study area. The data showed that levels of NO2, SO2, PM10 and PM2.5 increased when the inversions strengthened. Cases of two types of diseases (acute respiratory diseases and cardiovascular diseases), which are linked to atmospheric air pollution, were considered on number of patients under 15 and above 60 years old at National Geriatric Hospital and National Otorhinolaryngology Hospital. There was significant increase in the daily average number of hospital visits with increasing surface-based inversions. The statistical analysis showed that the temperature inversions correlated with concentration of air pollutants and the number of patients in 5 years.