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The biological macrofouling characteristics and electrochemical corrosion behavior of structural steel AH36 in natural seawater were studied continuously for 12 months at Hon Tre Island, Nha Trang – Vietnam. Electrochemical corrosion properties were studied using a PPGS-HHMC12 multi-channel device produced by the Institute of Chemistry, VAST. Tests were conducted at depths of 0.6 m, 1.8 m, and 3.0 m; under anti-macrofouling control, rotary movement, and under laboratory conditions as a comparison option. The results showed that macro-fouling formed and grew rapidly in both quantity, size and biomass in the next 3 months, then slowly and stably increased to about 8 months (6.06 kg.m-2). The OCP shifted to a positive potential, then reached a stable value of about -550 mV during the rest of exposure time. The corrosion current density decreased sharply from the first month to the fourth month, then reached a stable value of about 10 µA.cm-2 in next months of testing. The corrosion rate of AH36 steel in natural seawater in the field was higer than that under laboratory condition, which could be explained by the interaction of many factors such as dissolved oxygen, biofouling, water current, solar radiation

Human resources, especially high-quality human resources, play a decisive role in the socioeconomic development of each country. Binh Duong is in the Southeast region of Vietnam, which is located almost at the center of the arterial roads in the South. After 25 years of re-establishing the province, Binh Duong has made important progress and is contributing more to the overall growth of the Southern Key Economic Zone in particular and the country in general. This study is conducted to go into understand and analyze theoretical and practical issues related to developing human resources in Binh Duong province in the current period. The article pointed out and analyzed contents related to the challenges that high-quality human resources in Binh Duong face: imbalance and discord in high-quality human resources; the skill level is still low; executive capacity and management of many state management agencies have not kept pace with the development. Solutions to develop high-quality human resources in Binh Duong in the current context will be: continuing to strengthen the institution; focusing on the education and training of high-quality human resources; developing the digital economy. The limitation of this study is that it has not stated and analyzed the factors affecting the development of high-quality human resources in Binh Duong province, Vietnam in the current period.

This study was carried out to isolate and determine the Vibrio spp. from the Red drum fish (Sciaenops ocellatus) suffering from the hemorrhagic disease in Vietnam. In this study, 18 strains of Vibrio bacteria were identified from 27 samples of Red drum fish. The isolated bacterial strains were identified with the 16S rRNA sequencing method and checked for morphological, physiological, and biochemical characteristics by using the API 20E KIT. Results of the study revealed the presence of twelve strains of V. alginolyticus, three strains of V. fluvialis, and three strains of V. orientalis. All Vibrio strains have gene similarities with those on the Genbank ranging from 98.05 to 100%. The biochemical characteristics of these 18 isolates were similar and these are susceptible to tetracycline and doxycycline and entirely resistant to ampicillin, amoxicillin, and erythromycin.

Currently, multimode treatment is current therapy for cancer that causes various unwanted side effects and costliness for patients. Therefore, finding new natural ingredients derived from plants of which are less toxic and more targeted, are considered to be urgent for development of potential effective drugs to treat cancer due to safety and economic concerns. Physagulin P (VPA22) was known as a novel structural compound, isolated from the species Physalis angulata of the genus Physalis in Vietnam. This active substance has demonstrated cytotoxic effect on lung cancer cell line (A549) with the IC50 value = 13.47±2.73 µM. In our study, VPA 22 was investigated for apoptotic inducing activity on A549 cells by using Hoechst staining, flowcytometry analysis and caspase-3 colorimetric assay. VPA 22 treatment changed the morphology of A549 tending to apoptotic cells whose percentage ranged from 10.09% to 19.18% at the concentration of 5 µM and 15 µM, respectively. In addition, the active ingredient at concentration of 5 µM to 15 µM also significantly activated caspase-3 in turn from 1.30 folds to 2.59 folds. These results together indicated that VPA 22 activated the caspase pathway to trigger out apoptosis on A549 cells and subsequently resulted in inhibition of cancer cell proliferation.

This work demonstrated the fabrication of bimetallic Fe–Cu-BTC which able to provide large surface area, good electrocatalytic efficiency in combination with gold nanoparticles (flakes shapes) in order to detect bisphenol A in water samples.

Objective: This study was done to report the results of genetic diversity and toxic genes analysis of Vibrio pathogen isolated from white leg shrimp and marine fishes cultured in Thua Thien Hue province, Vietnam. Methods/statistical analysis: Pathogen Vibrio spp. were isolated from shrimps and fishes, and were identified by 16S rRNA sequencing. The presence of toxin genes in Vibrio spp. strains were determined through the presence of genes encoding toxic proteins (pirAvp, pir-Bvp, tlh, tdh and trh) based on specific primers for these genes. Genetic diversity of Vibrio strains was analysed by RAPD technique. Findings: A total of 120 Vibrio colonies from shrimps (with Acute Hepatopancreatic Necrosis Disease) and fishes (with hemorrhagic disease) cultured in Tam Giang lagoon in Thua Thien Hue, Vietnam were isolated. Of which, 14/54 strains from shrimps had pirAvp and pirBvp genes and 18/66 strains from fishes had tlh gene, and none of Vibrio strains had tdh and trh genes. Randomly amplified polymorphic DNA (RAPD) analysis of 36 Vibrio samples showed the 148 polymorphic DNA fragments from ten random primers. The genetic diversity is high within studied species. In there, V. parahaemolyticus has the highest diversity level (h=0.1645 and I=0.2695) while V. shilonii is lowest (h=0.0136) and I=0.0207). The degree of genetic differentiation among species is also high (Gst=0.4827). Genetic identity between V. parahaemolyticus and V. vulnificus (0.9545) is highest while between V. shilonii and V. harveyi (0.7416) is lowest. The dendrogram also showed that V. parahaemolyticus is closely related to V. vulnificus whereas V. shilonii and V. harveyi have large distance. Application/improvements: This study is aimed to provide scientific data as the basis for the study and production of rapid diagnostic kits in the future. Keywords: AHPND; Genetic diversity; RAPD; toxic genes; Vibrio; Vietnam

Cá Hồng mỹ (Sciaenops ocellatus) là loài cá biển có giá trị kinh tế cao và là đối tượng nuôi phổ biến ở Việt Nam, nhưng bệnh xuất huyết lở loét do vi khuẩn V. alginolyticus đang là thách thức chính cho nghề nuôi loài cá này tại Thừa Thiên Huế. Nghiên cứu này xác định hoạt tính kháng vi khuẩn của cao chiết từ cây Diệp hạ châu (Phyllanthus amarus) đối với 5 chủng V. alginolyticus được xác định là tác nhân gây bệnh xuất huyết trên cá Hồng mỹ. Cao chiết ở các nồng độ 100–500 mg/mL đều có khả năng kháng vi khuẩn V. alginolyticus, cao nhất ở nồng độ 500 mg/mL với đường kính vòng kháng lớn nhất (p < 0,05). Nồng độ ức chế tối thiểu (MIC) dao động từ 6,25 đến 25 mg/mL; nồng độ tiêu diệt tối thiểu (MBC) dao động từ 25 đến 50 mg/mL; tỷ lệ MBC/MIC từ 2 đến 4. Nồng độ cao chiết từ 50 đến 2.000 mg/mL cũng an toàn đối với cá Hồng mỹ ở giai đoạn giống.

Data were collected from 30 strains of Vibrio and sampled on different organs (brain, hemorrhagic site and digestive tract) of Sciaenops ocellatus infection. The results showed that the nucleotide sequences 16S rRNA region are highly similar to those of V. alginolyticus, V. azureus, V. fluvialis, V. natriengens and V. orientalis, which were published on Genbank and other, ranging from 98.05 to 100%. The digestive tract has the most common Vibrio strains (V. alginolyticus [16] V. azureus [7] and V. fluvialis). Thereout, 25 of 30 strains of Vibrio contained 1 to 3 toxin genes, except V. parahaemolyticus. Six parameters were used to measure the DNA polymorphism of 33 homologous DNA sequences in this Vibrio bacteria population. The results indicated that number of separate polymorphic sites (S), total number of mutant sites (Eta), number of haplotype (h), haplotype diversity (Hd), average number of nucleotide differences (k), nucleotide diversity (Pi) were 98 (S), 103 (Eta), 9 (h), 0.887 ± 0.032 (Hd), 25.789 (k) and 17.980 × 10–3 ± 0.003 (Pi), respectively (P Vibrio on 3 organs of fish (S. ocellatus) hemorrhagic are V. azureus (27,67%), V. alginolyticus (50%), V. orientalis (6,67%) and V. fluvialis (16,67%). Through this result, we found that the diversity of Vibrio species that appeared on the red drum was used in the 16S rRNA region and the presence of toxin genes in these Vibrio species.