Vietnam Academy of Science and Technology: Journals Online
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Aplication of immunofluorescence in combination with high-content imaging to screen the anti-translocation of nuclear factor NF-κB
No full textNuclear factor-kappa B or NF-κB is an essential transcription factor that regulates the expression of pro-inflammatory cytokine encoding genes in the pathophysiology progression of inflammation and cancer. This study lays out the result of the experimental application by using immunofluorescence technique combined with high-content imaging and analysis to detect the translocation of the nuclear NF-κB p65 factor binding with the green fluorescent protein (GFP) activated by cytokine in the cervical cancer cell line, HeLa. Under optimized conditions, the image was acquired with a sufficient quality for further analyses as well as a high reliability as the Z-factor was defined by the protein ratio in the nucleus (Nu) and cytoplasm (Cyto) to be 0.70 for Nuc-Cyto and 0.73 for Nuc/Cyto, respectively. As the result, a zerumbone sample (SHTN-4, 25 µg/mL) inhibited NF-κB activation as a high amount of cytoplasmic protein p65-GFP (82%) was determined in comparison to that of negative control (19.4%) after treatment of HeLa cells with IL-1 inducers at 10 ng/mL for 1h. This result can serve to develop a standard operating procedure to qualitatively analyze the intracellular protein for the biomolecular-targeted screening of anti-inflammatory and anti-cancer active compounds in accordance with domestic conditions
Research and development of genetically engineered soybean using insect-resistance genes derived from Bacillus thuringiensis
No full textSoybean (Glycine max) is one of the crops which have high economic value and serve for food, feed and process of many countries around the world. However, there are many factors affecting the productivity of soybean, of which insect pests and diseases are the most harmful agents. Therefore, an application of biotechnology to transfer insect resistance genes derived from a species of bacteria Bacillus thuringiensis can contribute to increase soybean yield and significantly reducing pesticide use. Currently, there are many insecticidal proteins detected from B. thuringiensis such as Cry, Cyt and Vip with a broad and specific spectrum belonged to several orders Lepidoptera, Diptera, Coleoptera, Homopera, and Nematoda. Numerous studies have been implemented over the world to transfer genes encoding these proteins in combination or modified forms to increase their toxicity. Several events of genetically engineered soybean with stacked traits of insect resistance and herbicide tolerance are commercialized and approved to be cultured in many countries such as MON 87701 × MON 89788 or DAS-81419-2. In Vietnam, studies on genetically engineered soybean with insect resistance trait has been carried out. Moreover, the exploitation, screening and selection of high biodiversity and indigenous B. thuringiensis strains which habors specific genes capable of killing targeted insects and serve as materials for plant transformation are great scientific meaning and potential practical application. This will be an important source of materials to create many soybean cultivars with good ability of insect resistance in order to meet specific needs
EFFECTS OF HEAD GAPS AND ROTOR GAP ON FLOW RATE AND HYDRAULIC LEAKAGE OF A NOVEL NON-CONTACT ROTOR BLOWER
No full textThe Roots blower belongs to the non-contact rotor pump family, therefore, there are always certain clearances between rotors and clearances between the rotor and the stator. These clearances have serious effects on the working performance of blower. Therefore, to determine the design error and the method of machining to achieve the lowest price, required machining technology, flow rate and pressure, the determination of leakage flow rate and pressure through the head gap and rotor gap is very necessary. Thus, in this paper, the authors conduct to build a mathematical model in order to determine the flow rate and pressure of blower in the ideal case in which there is no clearance and the case in which there are clearances. On that basis, the authors aim to evaluate the impact of head gaps and rotor gap on flow rate and pressure leakage. In order to improve the working performance of blower and to choose the machining method that is suitable for the applications of this blower
TREATMENT EFFICIENCY OF PIGGERY WASTEWATER BY SURFACE AND HORIZONTAL SUBSURFACE FLOW CONSTRUCTED WETLANDS
Get PDFConstructed wetlands have been used to treat various types of wastewaters such as urban runoff, acid mine drainage, municipal, industrial, and livestock wastewaters. This study is conducted to evaluate the effectiveness of two constructed wetlands (surface and horizontal subsurface flows) for piggery wastewater treatment after biogas process. The wetland plant Phragmites australis Cav. was used in 45 days for the experiments. The CWs were designed to treat up to 100 liters/day with the hydraulic retention time (HRT) of 3 days. Parameters including pH, COD, TSS, NH4+-N, total nitrogen (TN) and total phosphorus (TP) were measured. The pH of the CWs system was in the range of 6.7 to 7.3. The results showed that the horizontal subsurface flow CW had better treatment performance compared to the surface flow system. The removal efficiency of TP, TSS, COD, TN and NH4+-N by surface flow CW was 80, 60, 66, 60 and 65%, respectively while those by horizontal subsurface flow system was 86, 78, 74.6, 67.1 and 74.2%, respectively. The water quality of the effluents of both two CWs met the Vietnamese standards for livestock wastewater (QCVN62/2016-BTNMT, column B)
Effect of cerium salt-activated ceria on the UV degradation resistance of waterborne epoxy coatings
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Investigation of salt-tolerant rhizosphere bacteria from seawater-intruding paddy rice field in Vietnam
Get PDFSalt‐tolerant plant growth‐promoting rhizobacteria (ST‐PGPR) are known as potential tools to improve rice salinity tolerance. In this study, we aimed to investigate the plant growth‐promoting rhizobacteria community richness of the paddy rice fields in Soc Trang and Ben Tre Provinces where were seriously affected by sea level rise. The salinity in the sampling sites ranged from 0.14‰ to 2.17‰ in November 2018, the rainy season. The microbial abundance of samples was evaluated by spreading the samples in tryptic soy agar (TSA) medium supplemented with various concentrations of NaCl. With the increase of salt concentration up to 10% NaCl, a total number of bacteria decreased for all the samples, ranging from 106 to 104 CFU/g, and bacterial colonies were not observed at 30% NaCl. Among a total of 48 salt-resisting bacteria isolated from the rice paddy field mud surrounding the rice root, 22 isolates were able to produce indole-3-acetic acid (IAA: phytohormone for the plant growth). Seventeen out of 48 isolates were able to grow in the medium without nitrogen or phosphor sources. Six isolates having high IAA producing activity, nitrogen fixation and phosphate solubilization were belonged to Bacillus (DT6, LT16, and LHT8), Halobacillus (DT8), Aeromonas (LHT1), and Klebsiella (LHT7) genera. All the sequences of the strains DT6, DT8, LT16, LHT1, LHT7, and LHT8 were registered in the GeneBank with the accession numbers MK335670, MK335671, MK335672, MK335673, MK335674, and MK335675, respectively.
Variability of sea surface chlorophyll_a concentration in the South Vietnam coastal waters related to enso phenomenon
No full textThis paper focuses on analyzing the monthly averaged sea surface chlorophyll_a concentration data for 16 years (Jul. 2002 ÷ Sep. 2018), a remote sensing data product of the US National Aeronautics and Space Administration (US NASA), the analyzed results have shown that each occurrence of ENSO phenomenon greatly affects the fluctuation of chlorophyll_a concentration in the South Vietnam‘s coastal waters (SVNC). The monthly averaged chlorophyll_a concentration varies from 0.5 [mg/m3] to 1.1 [mg/m3] (equivalent to 22.4% ÷ 49.3%), while the monthly averaged fluctuation of chlorophyll_a concentration between months is only 0.22 [mg/m3] (equivalent to 9.88%). These fluctuations have a great impact on nutritional resources as well as water quality because chlorophyll_a is a pigment in plankton, which is a criterion to assess the "rich or poor" of nutrition source in seawater. The results of this study are considered as a "small piece" in the overall picture of the impact of ENSO phenomenon on global climate change
Characteristics of Simulated Workplace Neutron Standard Fields
Get PDFThis paper presents the development of simulated workplace neutron standard fields at the Institute for Nuclear Science and Technology with the 241Am-Be source moderated by polyethylene spheres with diameters of 15 cm and 30 cm. The characterization of the standard fields (in terms of neutron fluence rates and neutron ambient dose equivalent rates) was performed using Bonner sphere spectrometer system together with MAXED and FRUIT unfolding codes. The related quantities such as neutron dose equivalent-averaged energies and fluence-to-ambient dose equivalent conversion coefficients were also determined. The discrepancies of values are satisfied the standard uncertainty criteria as recommended by the International Standard Organization 12789 series. It implies that the simulated workplace neutron standard fields can be applied in the practical works for calibration purposes
Dynamics of Electroweak Phase Transition in the 3-3-1-1 Model
Get PDFThe bubble nucleation in the framework of 3-3-1-1 model is studied. Previous studies show that first order electroweak phase transition occurs in two periods. In this paper we evaluate the bubble nucleation temperature throughout the parameter space. Using the stringent condition for bubble nucleation formation we find that in the first period, symmetry breaking from , the bubble is formed at the nucleation temperature GeV and the lower bound of the scalar mass is 600 GeV. In the second period, symmetry breaking from , only subcritical bubbles are formed. This constraint eliminates the electroweak baryon genesis in the second period of the model
Amplification of useful vibration using on-off damping
Get PDFThis paper points out how much useful vibration can be extracted from a base-excited oscillator, which is controlled by the on-off electrical damping. We study the class of on-off electrical damping controller, which switches the damping level from high to low and back at fixed times every quarter of period. The problem reduces to the maximization of a single-variable function. This result can open the new direction to amplify the useful vibration using controllable dampings