Vietnam Academy of Science and Technology: Journals Online
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Effects of alcohol extract from defatted soybean meal on bile acid level, digestive enzyme activity and nutrient digestibility of pompano (Trachinotus blochii)
No full textDefatted soybean meal (SBM), which is produced by defatting soybean with solvents, has been considered as the most cost-effective substitute for fish meal (FM) in fish diets. However, SBM contains alcohol-soluble components which may interfere with growth performance and digestive physiology of fish. This study examined the effects of alcohol extract (Ext) containing alcohol-soluble components extracted from SBM on bile acid level, digestive enzyme activity and nutrient digestibility of pompano Trachinotus blochii. SBM was processed and separated into Ext and ethanol-extracted SBM (ESBM), thus, ESBM was SBM without alcohol-soluble components. Four experimental diets were formulated, denoted as FMD (FM-based diet), SBMD (SBM-based diet), ESBMD (ESBM-based diet), and ESBM+ExtD (ESBM-based diet plus Ext). Each diet was fed to two groups of fish (20 fish/group, 25 g/fish) for 4 weeks. Results showed that plasma lipid components, anterior intestinal bile acid level, anterior intestinal trypsin and lipase activities, and protein and lipid apparent digestibility coefficients (ADCs) of SBMD -fed fish were similar to those of ESBM+ExtD-fed fish. These parameters were significantly lower in SBMD-fed and ESBM+ExtD-fed fish than in ESBMD-fed and FMD-fed fish (P 0.05). There were no significant differences in plasma total cholesterol level, trypsin activity, and protein ADC between ESBMD and FMD groups, however, total bile acid level, lipase activity, and lipid ADC were significantly lower in ESBMD -fed fish than fish fed FMD (P 0.05). These results indicated that alcohol extract containing alcohol-soluble components extracted from SBM inhibited the secretions of bile acids and pancreatic digestive enzymes in pompano fish, and these abnormalities might impair nutrient digestion and absorption. The findings of the present study suggested that removing alcohol extract and supplementation of taurine could be effective for improving nutritional quality of SBM and enhancing feed utilization and growth performance of pompano which were fed SBM-based diets.
Additional records of the genus Acropimpla townes (Hymenoptera: Ichneumonidae: Pimplinae) from Vietnam and an updated key to species
No full textTwo species of the genus Acropimpla, viz. A. bicarinata (Cameron) and A. uchidai (Cushman), are recorded for the first time from Vietnam. An updated, illustrated key to all eight Vietnamese species of Acropimpla is provided.
Effects of 6-dimethylaminopurine, cytochalasin B and cycloheximide on in vitro development of I pig cloned embryos
No full textThe present study was conducted to evaluate the effects of 6-dimethylaminopurine (6-DMAP), cytochalasin B (CyB) and cycloheximide (CHX) on in vitro development of “I” pig somatic cell nuclear transfer embryos. Oocytes after SCNT were activated with 2 mM 6-DMAP; 7.5 µg/ml CyB and 10 µg/ml CHX. The results indicated that the rate of oocytes no lysis in group activated by CHX was significantly lower compared with those in group activated by 6-DAMP and CyB (90.91% and 88.01%, respectively, P 0,05). The blastocyst formation rate did not differ between group actvated by 6-DAMP and CyB (24.93% vs 24.4%, P 0.05). Meanwhile the blastocyst formation rate in group activated by CHX was 15.01%, significantly lower than that in group activated by 6-DAMP and CyB (P 0.05). The average number of cells in the blastocyst in group activated by 6-DAMP and CyB were higher than that in group activated by CHX (47.78, 44.57 vs 39.42, respectively). The use of 6-DMAP and CyB in the activation of pig oocytes after SCNT was more effective than CHX. The results of this study show that for the first time in Vietnam, we have created “I” pig SCNT embryo without zona pellucida with the rate of blastocyst formation from 15.01% to 24.93%
Study on tuberization of Rehmannia glutinosa (Gaertn.) Libosch.
No full textRehmannia glutinosa (Gaertn.) Libosch. is an herbal plant, which belongs to the Srcophulariaceae family, containing the main active ingredients such as catalpol and verbacoside in its root tubers. In traditional medicine, R. glutinosa tubers have been used in the fresh or dried tuber root or the prepared rehamannia root. They not only possess the comprehensive pharmacological actions in the blood system, endocrine system but also used mainly for anti-tumor treament, immune-enhancement, anti-diabetes, treament for concretion in the urinary tract, etc. R. glutinosa is naturally distributed in China, Korea and Japan. This species was introduced into Viet Nam since 1958 and then planted widely in many the Northern plain and midland provinces. In Vietnam, R. glutinosa produces flowers without seeds, therefore the plant has been mainly propagated by slicing tubers. In this work, we investigated the effect of some plant hormones and sucrose contents on the ability to producing microtubers of R. glutinosa. Experiments were establishmented on the 1/4 MS medium supplemented with 50g/L sucrose. Results showed that auxin (IBA, NAA) had no effect on the in vitro tuber formation of R. glutinosa. The efficiency of using the single BAP or PP333 was low. The highest in vitro tuberization rate of R. glutinosa obtained on the medium supplemented with the combination of BAP (1.0 mg/L) and PP333 (0.3 mg/L), reached 83.33% and the number of tubers/plant was 5.58. The optimal sucrose concentration for increasing the diameter and weight of microtubers was 70 g/L. 100% of plants with tuber-roots survived in the nursery and thrived on the fiel
Study of UGT1A1*28 genetic polymorphism related to irinotecan response in Kinh Vietnamese
No full textIrinotecan is a medicine commonly used to treat cancer. Carboxylesterase converts irinotecan into SN-38, a substance with 100 times more cytotoxicity than the original compound. SN-38 is inactivated by glucuronidation in the liver to the inactive form of SN-38 glucuronidation. UGT1A1 is the main enzyme responsible for the glucuronidation SN-38 secretion. Neutropenia and diarrhea are dose-limiting toxicity of the drug. UG1A1*28 variant is believed to increase the risk of neutropenia and is closely related to the risk of severe diarrhea. In this study, we used the direct sequencing method of the promoter UGT1A1 gene to determine the genotype and allele frequency of UGT1A1*28 in 95 individuals of healthy Kinh Vietnamese . The results showed that UGT1A1*28 variant is present in homozygousand heterozygous genotypes with frequencies of 14.74% and 1.05%, respectively. The allele frequency of the UGT1A1*28 variant was 8.421% which was small compared with the wild type allele *1 (91.579%). The data obtained from the study contribute to an effective cancer treatment solution using the drug irinotecan
Facile Synthesis and Characterization of the Reduced Graphene Oxide/CoO Nanocomposite for Capacitive Application
No full textReduced graphene oxide/CoO (rGO/CoO) were prepared by simple ultrasonic method from graphene oxide (GO) and Co(CHCOO) precursor. The synthesized rGO/CO3O4 was thoroughly characterized by SEM/EDX, XRD, FTIR and BET. The obtained results indicate the presence of well-crystalized CoO nanoparticles onto the rGO nanosheets in the lamellar structure of rGO/CoO. Despite slight decrease in BET specific surface area (from 389.9 m/g of rGO to 218.7 m/g of rGO/CoO), cyclic voltammetry studies show that the rGO/Co3O4 electrode exhibited high specific capacitance (95.8 F/ g at 50 mV/ s) with redox properties. The synthesized composites are expected to be a potential electrode candidate in supercapacitor as well as in hybrid capacitive deionization (HCDI) system for the desalination purpose
Initial understanding and assessment of role of oceanographic features for ferromanganese crusts and nodules in the East Vietnam Sea
No full textThe iron and manganese content in marine water is very small but the volume of ferromanganese nodules contributes 30% of the total mass of polymetallic nodules and crusts in marine and ocean floor. This suggests that the process of enrichment of ferromanganese crusts and nodules is not only contributed by chemical processes but also by oceanographical and biological processes. The article indicates the initial results of analyzing oceanographic, biological, and environmental features to understand their roles in the growing ferromanganese crusts and nodules and to predict the distribution of ferromanganese crusts and nodules in the East Vietnam Sea. As a result, ferromanganese crusts and nodules in the East Vietnam Sea can be distributed in the continental slopes, where upwelling and downwelling currents occur, to ensure enough dissolved oxygen concentration for the enrichment of ferromanganese crusts and nodules as well as to meet required conditions for microbial activity, which is involved in these processes. However, due to the limitations of the results of studying the enrichment of ferromanganese crusts and nodules in the East Vietnam Sea, the paper just shows the prediction of the distribution of ferromanganese crusts and nodules. Thus, it is necessary to carry out the expedition for enrichment processes of ferromanganese crusts and nodules and to determine the factors that impacted the growing ferromanganese crusts and nodules in the East Vietnam Sea
INCREMENTALLY UPDATING APPROXIMATION IN INCOMPLETE INFORMATION SYSTEMS UNDER THE VARIATION OF OBJECTS
No full textRough membership functions in covering approximation space not only give numerical characterizations of covering-based rough set approximations, but also establish the relationship between covering-based rough sets and fuzzy covering-based rough sets. In this paper, we introduce a new method to update the approximation sets with rough membership functions in covering approximation space. Firstly, we present the third types of rough membership functions and study their properties. And then, we consider the change of them while simultaneously adding and removing objects in the information system. Based on that change, we propose a method for updating the approximation sets when the objects vary over time
Effect of Graphene-Gold Nanocomposites on the Photocatalytic Activity Of TiO
Get PDFThe synthesis of graphene (Gr) - gold (Au) nanoparticle (NP) composite was achieved using continuous ultraviolet wave exposure. The functional groups were investigated with FT-IR spectra. From the Raman spectra, D-band and G-band of graphene were identified. As a result, the uniform deposition of nanometer-sized Au NPs on the graphene sheets was observed from the field emission scanning electron microscope (FE-SEM) images. The photodegradation of methylene blue in aqueous solutions is studied using various photocatalysts, including neat TiO2, Gr/TiO2 and Gr-Au/TiO2 composites. The Gr weight ratio in this research is 2%. The Gr2%-Au0.1%/TiO2 composite had the highest photoactivity
Modeling effects of abiotic and anthropogenic factors to rice production - A case study in Sapa district, Lao Cai province, Vietnam
No full textThe famous terraced rice ecosystem in the mountainous areas as Sapa of northern Vietnam has expanded with unstable productivity over generations. However, the question arises of how natural and human conditions on terraces can boost the quality of rice provisioning ecosystem service supply with rice yields as an indicator. The study used a semi-structured interview method, the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) tool and general linear models to investigate the influence of natural and human-derived components on the rice provisioning service at six villages. The results showed that along with the importance of applying a fertilizer-based system in the terraced rice ecosystem, topology- and hydrology-based systems have been influencing significantly on water and nutrient supply for irrigation on terraced rice fields. Moreover, analyzing the natural components has been considered more efficient than human-derived components for a sustainable rice ecosystem. The results indicated that the high potential of rice provisioning service supply had found at the downstream of Ta Van sub-catchment and the Vu Lung Sung village where the distance from paddy fields to sinks or outlet of streams is lower than five kilometers. The last result of the synthetic model proving 74.28 percent of deviance of terraced rice production did not avoid many noises in collecting and standardizing data that also discuss in this study