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ANTIOXIDANT POTENTIAL OF FIVE COMPOUNDS EXTRACT FROM THE MARINE FUNGUS ASPERGILLUS FLOCCULOSUS BY DFT METHOD: HAT AND SET MECHANISM.
No full textAntioxidant potential of five compounds include ochraceopone F (1), aspertetranone D (2), cycloechinulin (3), wasabidienone E (4) and mactanamide (5) in the extracts from marine fungus Aspergillus flocculosus in Nha Trang was investigated by computational chemistry methods. All calculations were performed at the theoretical level M05-2X/6-311++G(d, p)//M05-2X/6-31+G(d) in the gas phase. The physicochemical properties such as bond dissociation energies (BDE), ionization energies (IE), electron affinity (EA) characterizing HAT (Hydrogen atom transfer) and SET (Single electronic transfer) antioxidant mechanisms were calculated.As a result, the H-atom donating ability of the studies compounds increases in the descending order of BDE value (1) (2) (3) (4) » (5). Wherein the compounds (4) and (5) represent as the most potential antioxidant with the lowest BDE in the gas phase being 74.9 and 75.1 kcal/ mol. Moreover, the electronic donating ability of the compounds increases as function of the descending order of IE value (2) (1) (5) (3) (4). And the electron accepting abitlity decreases in decreasing EA value (4) (3) (2) (5) (1). Compound (4) (wasabidienone E) has the smallest IE value of 6.56 eV and has the largest EA value of 2.33 eV
A METHOD TO IMPROVE THE TIME OF COMPUTING BETWEENNESS CENTRALITY IN SOCIAL NETWORK GRAPH
Get PDFThe Betweenness centrality is an important metric in the graph theory and can be applied in the analyzing social network. The main researches about Betweenness centrality often focus on reducing the complexity. Nowadays, the number of users in the social networks is huge. Thus, improving the computing time of Betweenness centrality to apply in the social network is neccessary. In this paper, we propose the algorithm of computing Betweenness centrality by reduce the similar nodes in the graph in order to reducing computing time. Our experiments with graph networks result shows that the computing time of the proposed algorithm is less than Brandes algorithm. The proposed algorithm is compared with the Brandes algorithm [3] in term of execution time
HIGH PERFORMANCE LIQUID CHROMATOGRAPHY ASSAY FOR DETERMINATION OF MOXIFLOXACIN IN HUMAN PLASMA
Get PDFA simple reversed phase HPLC method with UV detection has been successfully developed and validated for determination of moxifloxacin in human plasma. The sample pretreatment involves only single-step protein precipitation with tricloroacetic acid. Moxifloxacin was measured in plasma using a validated HPLC method with UV detector at 295 nm, C18 column (25cm×4.5mm, 5µm), a mixture of phosphate buffer pH 4.0 and acetonitrile (70:30, v/v) as mobile phase at a flow rate of 0.8 ml/min. Retention time of moxifloxacin was found to be 7.4 min. The mean recovery for the drug was obtained 97.30%. The calibration curve was linear over the concentration range of 0.3 to 25.0 µg/mL with coefficient correlation of 0.9991. This method was successfully applied for therapeutic drug monitoring
ẢNH HƯỞNG CỦA ĐỘ MẶN ĐẾN HIỆU QUẢ SINH SẢN CỦA NGÁN BỐ MẸ (AUSTRIELLA CORRUGATA) TRONG ĐIỀU KIỆN NUÔI VỖ
No full textThis study was conducted to evaluate the effect of dietary, salinity on the reproductive efficiency of mud clam broodstock (Austriella corrugata) in the maturing condition. The reproductive efficiency was assessed by survival rate, maturation rate, actual fecundity, spawning rate, fertilization rate, reproductive efficiency rate (100*D-veliger/fertilized eggs), larval quality. The experiment was held in the five dietaries and three salinities (18‰, 23‰ and 28‰). Three replicates were carried out for each treatment. Results showed that the reproductive efficiency of using fresh algae complex in 28‰ salinity was the highest and the larvae are in good quality, followed by that in the 23‰ salinity but having no statistically significant difference ( p 0.05) while that in the 18‰ salinity experienced the least (p 0.05). This study on dietary, salinity suggests that fresh algae complex in the salinity of 28 ± 1‰ is suitable for maturing broodstock of mud clam. These findings will contribute to building up hatchery production techniques as well as helping protection of natural stock and developing sustainable mud clam resource.Nghiên cứu này được thực hiện nhằm đánh giá ảnh hưởng của độ mặn đến hiệu quả sinh sản của ngán bố mẹ (Austriella corrugata (Deshayes, 1843)) trong điều kiện nuôi vỗ. Hiệu quả sinh sản của ngán bố mẹ được đánh giá thông qua các chỉ tiêu về tỷ lệ sống, tỷ lệ thành thục, tỷ lệ sinh sản, sức sinh sản thực tế , tỷ lệ thụ tinh, tỷ lệ sinh sản hiệu quả (100*ấu trùng chữ D/trứng thụ tinh), chất lượng của ấu trùng. Thí nghiệm được tiến hành với 3 ngưỡng độ mặn khác nhau (18‰, 23‰ và 28 ‰ ), 3 lần lặp lại cho mỗi ngưỡng độ mặn. Kết quả cho thấy, ở độ mặn 28‰ hiệu quả sinh sản của ngán bố mẹ đạt giá trị cao nhất, ấu trùng khỏe. Ở ngưỡng độ mặn 23‰, hiệu quả sinh sản thấp hơn ngưỡng 28 ‰ nhưng sự khác biệt không có ý nghĩa thống kê (P0,05). Ở độ mặn 18 ‰,hiệu quả sinh sản đạt giá trị thấp nhất (p 0,05), ấu trùng yếu. Từ kết quả nghiên cứu này, ngưỡng độ mặn 28 ± 1‰ được đề xuất để nuôi vỗ ngán bố mẹ và khoanh vùng bảo vệ ngán bố mẹ vào mùa sinh sản ngoài tự nhiên.Từ khóa:Austriella corrugata, độ mặn, ngán bố mẹ, hiệu quả sinh sả
ANTIMICROBIAL, CYTOTOXIC AND HEMOLYTIC ACTIVITIES OF MARINE ALGAE-ASSOCIATED FUNGAL ISOLATES IN VIETNAM
No full textIn the context of sources for natural products discovery are going scarcer, exploiting biotechnologically potential compounds from marine microbial symbionts is considered a relatively new trend. In our study a total of fifteen fungal strains were isolated from marine algal samples belonging to species Kappaphycus cottonii, K. striatus, Gracilaria eucheumatoides and Betaphycus gelatinus collected in Nha Trang in 2017. The in vitro biological activities, including antimicrobial, cytotoxic and hemolytic activities of ethyl acetate extracts of the fungal strains were determined. From fifteen fungal extracts, six displayed antimicrobial activity against at least one test strain. At 20 μg.ml-1, four fungal extracts were found to express cytotoxic activity on two human cancer cell lines hepatocellular carcinoma (Hep-G2) and breast adenocarcinoma (MCF-7), with G. eucheumatoides being the source of the highest number of producer strains. Hemolytic activity was observed in rabbit erythrocytes under almost all fungal extracts’ effect. No apparent relationship was observed between the biological activities of fungal isolates. The biological assessments uncovered several fungal candidates, such as Bge-1.1, Kco-2.1 and Geu-1.1 with relatively potent antimicrobial and cytotoxic activities while expressing less hemolytic effect at concentrations from 20 μg.ml-1 to 200 μg.ml-1. The results evidenced the potential of exploiting natural products from associated marine microorganisms, especially those for the purpose of pharmaceutical applications
THÀNH PHẦN LOÀI VÀ PHÂN BỐ CỦA THÂN MỀM VÀ DA GAI RẠN SAN HÔ TRONG CHUYẾN KHẢO SÁT TRÊN TÀU VIỆN SĨ OPARIN NĂM 2016–2017
Get PDFA study on the species composition and distribution of Mollusca and Echinodermata on coral reefs from Quang Tri to Binh Thuan was conducted during the field survey between Vietnam and Russia on the AKADEMIK OPARIN RC vessel in 2016 and 2017 at 39 reef stations. 150 species were identified belonging to 100 genera, 50 families, 22 orders, 7 classes distributed on coral reefs. The species composition of mollusca and echinodermata was different between study areas.Nghiên cứu về thành phần loài và phân bố của động vật thân mềm, da gai trên rạn san hô khu vực từ Quảng Trị đến Bình Thuận được thực hiện trong chuyến khảo sát hỗn hợp Việt - Nga trên tàu Viện sĩ OPARIN trong thời gian từ tháng 11 đến tháng 12/2016 và chuyến khảo sát bổ sung từ tháng 5 đến tháng 7/2017 tại 39 trạm rạn thuộc 10 vùng nghiên cứu. Bằng phương pháp hình thái so sánh, nhóm tác giả đã xác định được 150 loài động vật thân mềm và da gai thuộc 100 giống, 50 họ, 22 bộ, 7 lớp phân bố trên rạn san hô. Thành phần loài thân mềm và da gai tương đối khác biệt giữa các vùng nghiên cứu
Bioclimatic assessments for tea cultivation in Western Nghe An
No full textBioclimatology is applied for growing tea in the West of Nghe An province, where the tea is considered as a high economic efficient plant to be priorly cultivated for reducing poverty and getting rich. Based on the bioclimatic characteristics of tea plant and regional climatic data from 1980 to 2014, the bioclimatic diagrams are built and the tea cultivability is mapped in term of annual average temperature and total precipitation, for this region with regarding its district of Con Cuong as an analytical key. The climate, including both temperature and precipitation, in Con Cuong is relatively suitable for the tea plantation. The Western Nghe An, a land of approx. 1.4 million ha, could be classified in five areas with different suitability for tea plant. The unfavorable area occupies only 1% of total region and the four favorable rests account for 99% of total, in which, the most favorable area is largest with about 746,355 ha, i.e. over 50% of whole region. The three other areas are cultivable but they are less favorable in terms of either temperature or precipitation. Growing tea in Western Nghe An, even in favorable areas, it should be taken into account of the weather disadvantages in certain moments of the year such as extreme dry, cold, hot and rainy events.ReferencesAhmed S., 2014. Tea and the taste of climate change, www.herbalgram.org, issue, 103, 44–51.Ahmed S., Stepp J.R., Orians C., Griffin T., Matyas C., 2014. Effects of extreme climate events on tea (Camellia sinensis) functional quality validate indigenous farmer knowledge and sensory preferences in tropical China. PloS one, 9(10), e109126.Bhagat R.M., Deb Baruah R., Safique S., 2010. climate and tea [camellia sinensis (l.) o. kuntze] Production with Special Reference to North Eastern India: A Review. Journal of Environmental Research And Development, 4(4), 1017–1028.Carr M., 1972. The Climatic Requirements of the Tea Plant: A Review. 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Magnetic Order in Heisenberg Models on Non-Bravais Lattice: Popov-Fedotov Functional Method
Get PDFWe study magnetic properties of ordered phase in Heisenberg model on a non-Bravais lattice by means of Popov - Fedotov trick, which takes into account a rigorous constraint of a single occupancy. We derive magnetization and free energy using sadle point approximation in the functional integral formalism. We illustrate the application of the Popov -- Fedotov approach to the Heisenberg antiferromagnet on a honeycomb lattice
THE REAL-WORLD-SEMANTICS INTERPRETABILITY OF LINGUISTIC RULE BASES AND THE APPROXIMATE REASONING METHOD OF FUZZY SYSTEMS
Get PDFThe real-world-semantics interpretability concept of fuzzy systems introduced in [1] is new for the both methodology and application and is necessary to meet the demand of establishing a mathematical basis to construct computational semantics of linguistic words so that a method developed based on handling the computational semantics of linguistic terms to simulate a human method immediately handling words can produce outputs similar to the one produced by the human method. As the real world of each application problem having its own structure which is described by certain linguistic expressions, this requirement can be ensured by imposing constraints on the interpretation assigning computational objects in the appropriate computational structure to the words so that the relationships between the computational semantics in the computational structure is the image of relationships between the real-world objects described by the word-expressions. This study will discuss more clearly the concept of real-world-semantics interpretability and point out that such requirement is a challenge to the study of the interpretability of fuzzy systems, especially for approaches within the fuzzy set framework. A methodological challenge is that it requires both the computational expression representing a given linguistic fuzzy rule base and an approximate reasoning method working on this computation expression must also preserve the real-world semantics of the application problem. Fortunately, the hedge algebra (HA) based approach demonstrates the expectation that the graphical representation of the rule of fuzzy systems and the interpolation reasoning method on them are able to preserve the real-world semantics of the real-world counterpart of the given application problem
