Vietnam Academy of Science and Technology: Journals Online
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INDOOR AND OUTDOOR RELATIONSHIPS OF PARTICLE WITH DIFFERENT SIZES IN AN APARTMENT IN HANOI: MASS CONCENTRATION AND RESPIRATORY DOSE ESTIMATION
No full textThis paper presents data on the size characterization concentration of PM0.1, PM0.5, PM1, PM2.5, PM10, TSP in indoor and outdoor air of a residential apartment in two seasons (winter and summer) in Hanoi, Vietnam. These particles with different sizes were taken by 5 stage impactors (Nano sampler 3182, KINOMAX). Daily average concentrations of coarse particles (PM10) and fine particles (PM2.5) indoors and outdoors exceeded the WHO recommended values. In winter, the concentrations of PM0.5, PM1, PM2.5 and PM10, TSP are higher than in summer. However, concentrations of PM0.1 (NP) remains negligible change between two seasons. The indoor NP accounts about 17% and 8 % of fine particle (PM2.5) and 12 % and 7% of coarse particle (PM10) in winter and summer, respectively. The indoor fraction for small sizes (NP, PM0.5, PM1 and PM2.5) have better infiltration than coarse sizes (PM10 and TSP), except for NP in summer. Moderate correlation between wind speed (Ws) and PM concentration are found, whereas precipitation (Pr), Relative humidity (RH) and temperature (T) correlate with concentration with different sizes are determined. Strong correlations between particles with different sizes are also found in indoors and outdoors (r = 0.73-0.98). Household activities like cooking, cleaning and vacuum cleaner are attributed to elevate the indoor NP. The Monte Carlo simulation shows that highest estimated dose is observed in the age group (over 60 years) and age group (0-3 years) suffers the lowest dose, which has implications in the adverse health effects for sensitive groups. Sensitive analysis find the concentration of particles to be the most influencing factor on inhalation dose estimation
BIO-OIL FROM RUBBER WOOD: EFFECTS OF UPGRADING CONDITIONS
No full textDespite its prominent potential, the use of rubber wood (Hevea brasiliensis) for bio-oil production has not been fully investigated. This study reported experimental results of the bio-oil production and upgrading from rubber wood using fast pyrolysis technology. The effects of catalyst nature (vermiculite and dolomite), upgrading temperature and bio-oil/catalyst ratio on the product quality were deeply investigated. The results showed that dolomite was suitable to be used as a catalyst for bio-oil upgrading. At 600 °C and a bio-oil/catalyst ratio of 1:1, the bio-oil yield was maximized, while at 400 °C and a ratio of 1:3, the bio-oil heating value was maximized. Depending on usage purposes, a yield-oriented, heating value-oriented or in-between bio-oil upgrading solution could be considered
Asymptotic theory for thin two-ply shells
No full textWe develop an asymptotic model for the finite-deformation, small-strain response of thin laminated shells composed of two perfectly bonded laminae that exhibit reflection symmetry of the material properties with respect to an interfacial surface. No a priori hypotheses are made concerning the kinematics of deformation. The asymptotic procedure culminates in a generalization of Koiter's well-known shell theory to accommodate the laminated structure, and incorporates a rigorous limit model for pure bending
Authentication of the green monkey kidney Vero76 cell lines subcultured through many generations
No full textThe Vero76 cell lines isolated from the kidney of an African green monkey (Chlorocebus aethiops sabaeus), are commonly used for viral culture, vaccine development, and cytotoxicity assays. However, subculturation of cell lines over multiple generations can lead to a genetic change in these cell lines compared to the original cell. This will lead to deviations in results of research that using the modified cell lines. Therefore, identification and evaluation periodically the genetic stability of cell lines after subculture are necessary. In recently studies, cell authentication by using STR markers (short tandem repeat markers) have been becoming a simple and effective method that used commonly. In this study, we used eight STR markers: D17S1304, D5S1467, D19S245, D1S518, D8S1106, D4S2408, D6S1017, and DYS389 for cell lines authentication and evaluation of the genetic stability of subcultured Vero76 cell lines. The STR indicators were amplified, sequenced and compared with the original cell to identify the differences between cell lines in subcultured generations. The evaluation results showed that these cell lines did not have any differ compared with the original cell line, this confirmed that the genetic of the cell lines were stability. The results also suggested that STR markers can be used to authenticate for Vero76 cell lines.
Haemagglutination activity of lectins from extracts of some Vietnam marine sponges
No full textAqueous extracts from 16 species of Vietnam marine sponges were examined for haemagglutination activity using native and enzyme-treated different animal and human erythrocytes. Among these, extracts from 14 species were found to have haemagglutinination activities toward at least one type of erythrocyte tested meaning that 87.5% of the surveyed marine sponge species possess haemagglutination activity. Strong activity was detected in extracts from marine sponge species Acanthella cavernosa, Axinyssa sp., Cinachyrella sp., 01NT.2.4, 3.5, 3.10, 3.11 and 3.18 with enzyme-treated various animal and human erythrocytes. In a haemagglutination–inhibition test with various monosaccharides and glycoproteins, haemagglutination activity of the extract from A. cavernosa had no affinity for any of the monosaccharides, but inhibited by porcine stomach mucin and fetuin, whereas activities of the extract from Cinachyrella sp. were strongly inhibited by monosaccharides, such as D-galactose and N-acetyl-D-galatosamine, but not with glycoproteins. The activity of Stylissa flexibilis extract was inhibited by D-galactose, porcine stomach mucin, fetuin and their asialo derivatives, suggesting the presence of lectin specific for O-glycans of this species. The activities of four sponge extracts from A. cavernosa, S. flexibilis, Axinyssa sp. and Cinachyrella sp. were stable over a wide range of pH and temperature. Haemagglutination activities of A. cavernosa, Axinyssa sp. and Cinachyrella sp. extracts were independent of the presence of divalent cations, except for the haemagglutination activity of extract from S. flexibilis, which was dependent on the presence of divalent cations. The results suggest that Vietnam marine sponges may be good sources of useful lectins for biochemical and biomedical applications
Evaluation of the effects of agricultural LED lighting on in vitro propagation of Cordyceps militaris (Link.) Fries
No full textIn this study, the effects of various agricultural LED lights (LED NN), including single red LED (R), single blue LED (B), and four combinations of blue, red, and warm white (W) LED (BR, BRW1, BRW2, BRW3) on the growth and development of C. militaris (Link.) Fries were evaluated in vitro. After 7 days, samples subjected to LED NN showed shorter sporocarp sprouting time and higher sprouting ratio than the control, which was subjected to T5 fluorescent light. After 2 months, LED lights with high red ratio, such as single red LED and LED BR, had suppressing effect on the growth and development of C. militaris (Link.) Fries. On the other hand, combinations of red, blue, and warm white such as LED BRW1, LED BRW2, and LED BRW3 had the positive impact on the growth and development of this fungus. Notably, samples subjected to LED BRW2 reached 5.79 cm in height, fresh biomass of 3.67 g/20 samples. Cordycepin and Adenosine levels were 64.2 and 6.37 mg/100 g fresh mass, respectively. All of studied indicators were the higher compared to those of the control and other LED lighting schemes. Therefore, it can be conlcuded that LED lighting combination with BRW2 ratio of 1:5:1 and luminous intensity of 45±2 µmol.m-2.s-1 (511,59 Lux) was suitable for the growth and development of C. militaris (Link.) Friesand a potential replacement of fluorescent light for C. militaris (Link.) Friesin vitro propagation
Whole exome sequencing identified a novel myopalladin gene mutation in a cardiomyopathy patient
No full textCardiomyopathies (CMs) are a heterogenous group of disorders that affects the heart muscle. Incardiomyopathies, phenotypic overlapping among the inherited cardiovascular diseases (CVDs) limits theability to establish a diagnosis based solely on clinical features. Here, we developed a next generationsequencing (NGS) assay to analyze a panel of 142 known cardiomyopathy genes in 9 Vietnamese patientsfrom Children Hospital 2, Hochiminh City and Medical University Hospital, Hochiminh City, Vietnam.Whole exome sequencing (WES) - a technique which determines the variations of all coding regions (exons)of the known genes - validated a total of 65 rare variants in 18 cardiomyopathy genes among the studiedVietnamese unrelated patients. Of 65 variants identified, 28 variants were homozygous and the other 37 oneswere heterozygous. Among the 65 variants, TTN gene variants accounted the most for 13 mutations, which areknown to be benign. Other groups of 9 and 8 mutations belong to SYNE1 and MYPN genes, respectively. Tenout of 65 mutations distributed equally to NDUFV2 and SCN5A gene variants. We detected 6 and 4 variantsfor SYNE2 and COX15 genes, respectively. Each gene of DMD, KCNE1, NEBL and RBM20 has 2 variants. Asingle variant was detected for AKAP9, CAV3, DSC2, DSG2, DSP, MYBPC3 and MYH6 genes. Especially,among them, we found a novel heterozygous nonsynonymous mutation c.1527CG on the MYPN gene. Thesegenetic results support the “pan-cardiomyopathy panel” approach, by which the molecular diagnosis ofcardiomyopathies, early identification of arrhythmia development and better clinical management ofcardiomyopathic patients are applied
Iron nanoparticles on growth and acclimatization of Chrysanthemum morifolium Ramat. cv. "Jimba" in different culture systems
No full textIn plant tissue culture, iron nanoparticles (FeNPs) was one of the first types of nano to be used in plants. Previous reports have identified the effect of FeNPs on many different plant species. In this study, FeNPs was used to replace Fe-EDTA in MS (Murashige, Skoog, 1962) medium to assess their effects on growth, chlorophyll (a, b and a+b) accumulation, antioxidant activity of ascorbate peroxidase (APX) and superoxide dismutase (SOD) enzymes, and acclimatization in greenhouse conditions in different culture systems (in vitro solid, in vitro hydroponic and microponic culture). The obtained results show that FeNPs added to MS medium was higher growth, chlorophyll (a, b and a+b) content, antioxidant activity of SOD and APX enzymes than Fe-EDTA in MS medium as control treatment. The effect of FeNPs are differences between culture systems. In vitro solid and microponic culture systems, the optimal concentration is 75 mM FeNPs and in vitro hydroponic culture system is 100 mM FeNPs. The optimal activity of the antioxidant enzyme SOD (35.04 U.mg−1 prot) obtained in the roots of cultured plants in microponic culture system; meanwhile, the optimal activity of the antioxidant enzyme APX (2.11 μmol.min−1.mg−1 prot) obtained in leaves cultivated in solid culture system. The plantlets derived from MS medium added FeNPs were transfered into greenhouse conditions, the microponic cultivated plants supplemented with FeNPs at a concentration of 100 mM gave the highest survival rate (94.67%). The results of this study showed that FeNPs can replace Fe-EDTA salt in MS medium, and iron deficiency in culture media will reduce chlorophyll content
Transient expression of gene encoding ZmLEA14A protein in Nicotiana benthamiana plant
No full textLEA protein family includes proteins accumulated in the late stage of embryogenesis and in vegetative tissues of stress-confronted plant. These proteins have been demontrated to play a major role in plant response to abiotic stresses, such as drought and salinity stress. The genes coding for LEA proteins in maize are divided into 9 groups including LEA 1, LEA 2, LEA 3, LEA 4, LEA 5, LEA 6, SMP, dehydrin, and AtM. The application of LEA genes to improve drought tolerance for plants by genetic engineering has also been studied extensively all over the world. In this study, pCAM/35S-ZmLEA14A-35S vector and pCAM/Ubi-ZmLEA14A-35S vector contained the ZmLEA14A gene isolated from Te vang 1, these vectors were used to transient express into Nicotiana benthamiana tobacco leaves by agro-infiltration method. The results of immunoassay between cmyc specific antibodies with proteins from infected leaves revealed the expression of recombinant ZmLEA14A protein in N. benthamiana leaves. Thereby, two constructs habouring the ZmLEA14A gene work at transcription and translation levels in the model plant that could harnessed for stable transformation in plants
Characterization of the C-type lectin from the marine sponge (Stylissa flexibilis)
No full textA lectin from the marine sponge Stylissa flexibilis, designated as SFL, was purified by cold ethanol precipitation followed by ion exchange chromatography on DEAE Sepharose column and Sephacryl S-200 gel filtration. SFL is a dimeric glycoprotein of 32 kDa subunits linked by a disulfide bridge with a molecular mass of 64 kDa by SDS-PAGE and 65 kDa by Sephacryl S-200 gel filtration chromatography. The lectin preferentially agglutinated enzyme treated human A erythrocytes, whereas it did not agglutinate any type of rabbit, human B and O erythrocytes, irrespective of treatment with enzymes. The hemagglutination activity of lectin was strongly inhibited by monosaccharide, D-galactose and glycoproteins, asialo-porcine stomach mucin and asialo-fetuin, indicating that lectin is specific for O-glycans. Activity of SFL was stable over a range of pH from 5 to 8, up to 60 °C for 30 min and its activity was Ca2+ dependent, indicating that SFL was belonged to the C-type lectin family and requires metal for biological activity. SFL caused agglutination of Vibrio alginolyticus and V. parahaemolyticus in a dose dependent manner and inhibited the growth rate of these bacterial strains, suggesting that the lectin caused the agglutination through binding to the target receptor(s) on the surface of Vibrios. Thus, SFL can be considered as a good source of lectin(s) being useful as carbohydrate probe and antibacterial reagent