Vietnam Academy of Science and Technology: Journals Online
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New records of bats (Mammalia: Chiroptera) from Cu Lao Cham and Ly Son archipelagos, central Vietnam
Get PDFCu Lao Cham and Ly Son are two well-known archipelagos of Vietnam for their specular landscapes and varied ecosystems including forest, cave, and agriculture. However, their bat fauna has received little attention. Between July 2017 and August 2018, we conducted a series of mammal surveys with emphasis on bats of the two archipelagos. Bats were captured by mist nets and harp traps. Echolocation calls of microchiropteran species were recorded using the PCTape system then analysed by Selena software. With reference to all available literatures and specimens from the recent surveys, we obtained confirmed records of 9 bat species from Cu Lao Cham and 3 species from Ly Son. Of these, Megaderma spasma and Taphozous melanopogon are new to Cu Lao Cham while Rhinolophus macrotis is new to Ly Son. These three species were rarely recorded from other islands of Vietnam and also uncommon within Cu Lao Cham and Ly Son. These new records not only expand the known distributional range, but also provide worthwhile notes on a narrow geographical variation in morphology and echolocation of each species
Regulation of apoptosis of dendritic cells by il-10 and in association with stat-1 signaling molecule
Get PDFIL-10 is an anti-inflammatory cytokine, participating in induction of immune tolerance and cell apoptotic death. Dendritic cells (DCs) is the most professional antigen-presenting cells among innate immune cells to exert generation and maintenance of immunological memory mediated through activation of T and B lymphocytes. The STAT signalling pathway plays a regulatory role of maturation and differentiation of immune cells. In this study, DCs were treated with inflammatory cytokines including TNF-a, INFg, IL-2 and IL-10 and subsequently examined the phosphorylation of STAT-1 and STAT-3, TNF-α concetration in cell suspension and the proportion of Annexin V+ and caspase 3+ cells. Methods used for this investigation include western blotting, flow cytometry and ELISA. DCs were derived from mouse bone marrow cells and cultured with GM-CSF for 8 days. As a result, IL-10, but not other cytokines enhanced the number of Annexin V+cells and caspase 3 activity in DCs. More importantly, IL-10 also increased the phosphorylation of STAT-1 as well as the release of TNF-α into cell suspension. In conclusion, activation of STAT-1 might relate to the cell apoptotic death and TNF-α sectetion in IL-10-treated DCs
Genetic variation and outcrossing rate of Dipterocarpus dyeri in the Tan Phu tropical rain forest (Dong Nai), Vietnam
Get PDFDipterocarpus dyeri (Dipterocarpaceae) is widely distributed in lowland rainforests in southeastern Vietnam. Due to over- exploitation and habitat destruction in the 1980s and 1990s, this species is listed as threatened. Understanding the genetic variation and mating rate among D. dyeri population that occurs in forest patches is necessary to establish effectively conservation strategies for this species. To conserve the species in tropical forests, genetic diversity and mating rate were investigated using eight microsatellites (single sequence repeat, SSR) as markers. All of the eight loci were polymorphic. A total of 36 different alleles were observed across the loci screened. The SSR data indicated high genetic diversity (NA = 4.5; HO = 0.542 and HE = 0.667) and high inbreeding value, FIS= 0,182. The mating system parameters were determined using the mixed mating model and the results indicated high outcrossing rate (tm=0.81 and ts=0.675) and lowselfing rate (0.19). Difference of tm-ts value indicated that inbreeding contributed to selfing rate for this species in the Tan Phu tropical rain forest. The results reflected that D. dyeri habitat in this area has been restored and the number of individuals was high, about 500 individuals. However, seedlings were not found so far in this study. These results indicated the importance of conserving of the genetic resources of Dipterocarpus dyeri species in the Tan Phu rain forest. The conservation strategy should include an establishment of an ex-situ conservation site with new big population for this species from all genetic groups, which might improve its fitness under different environmental stresses.
Diversity of plant-parasitic nematodes on medicinal plants in melinh station for biodiversity, Vinh Phuc Province, Vietnam
Get PDFPlant-parasitic nematodes are known as one of the most important pests attacking various plants in the world, and investigating the nematode component is very essential for management of this pest and prevent damage to plants in general. Our survey of plant-parasitic nematodes on medicinal plants in Melinh Station for Biodiversity, a place for conservation of precious plants and animals in Vietnam, identified ten species that belong to nine genera, five families, and two orders of plant-parasitic nematodes parasitizing six medicinal plants. Excoecaria cochinchinensis was parasitized by the highest number of nematode genera (5 genera, including Xiphinema, Discocriconemella, Meloidogyne, Helicotylenchus, and Hemicriconemoides), while Hymenocallis littoralis was associated with the highest number of plant-parasitic nematodes (2060 nematodes/250g soil). The results also showed that Discocriconemella limitanea was found to be a dominant species with the highest number of individuals on 6 medicinal plants, and the genus Helicotylenchus had the highest frequency of appearance (5/6 plants or 83.3%). These nematodes caused symptoms such as yellowing leaves, root galls, and root lesions, which directly affect the quality and yield of medicinal plants. Based on the results, this study showed that plant-parasitic nematodes are a potential threat to the cultivation of medicinal plants in Melinh Station for Biodiversity, and thus, control measures should be applied to ensure sustainable cultivation of medicinal plants in this place
BACTERICIDAL ACTIVITY OF NANOSILVER AGAINST PATHOGENIC MICROORGANISMS WHICH CAUSE PECULAR DISEASES OF GENITAL SECRETION TRACK
Get PDF Nano silver was known as a bactericidal agent for almost all bacterial species and has been intensively investigated over the world to apply for disinfection in different fields of human activities and environmental protection. Specifically, genital exudate media contain numerous dangerous bacteria such as Neisseria gonorrhoeae, Enterococcus faecalis, Staphylococcus aureus, Candida albicans etc. which as a rule are drug-resistant with respect to antibiotics. This research presents the results of the application of nanosilver in replacing antibiotics in elimination of the above mentioned microorganisms by using low nanosilver concentrations of about 0.01 mg/cm2 immobilized on non-woven fabric. The experimental data showed that nanosilver-impregnated fabric samples at a concentration 0.01 mg/cm2 gave antibacterial rings of 10 mm, 9 mm and 8 mm, respectively, for N. gonorrhoeae, Candida albicans + E.coli and Candida albicans + E.coli + S. aureus
DNA BARCODING APPLICATION OF MITOCHONDRIAL COI GENE TO IDENTIFY SOME FISH SPECIES OF FAMILY GOBIIDAE IN VIETNAM
No full textThe family Gobiidae is a relatively high abundance family of coastal fish with about 2000 species in 210 genera described. In Vietnam, the study on Gobiidae is very complex due to the large number of species, small size and high morphological variation which makes difficulties in identification and classification. In this study, the DNA barcoding technique has been used through mitochondrial cytochrome oxidase I (COI) gene to classify 30 specimens of Gobiidae from three coastal areas (North, Central and South) in Vietnam to evaluate the effectiveness compared to the morphological classification method. Results showed that 26 species belonging to 21 genera were determined by the COI barcode while 19 species (17 genera) were determined when using morphological method. Mahidolia mystacina was new recorded in Vietnam. The DNA barcodes of COI gene developed in this study could be useful for estimating phylogenetic diversity as well as other studies of gobiids in terms of conservation, management and utilization of fisheries resources in Vietnam. In addition, the results showed the high potentiality in using COI barcode to identify marine fish
ẢNH HƯỞNG CỦA NỀN ĐÁY CÁT VÀ ĐÁ SỐNG LÊN CHẤT LƯỢNG MÔI TRƯỜNG BỂ NUÔI CÁ CẢNH BIỂN
Get PDFMarine ornamental aquarium is more and more popular. Nowadays, biofiltration system can convert nitrogen from toxic forms (NH4+/NH3, NO2-) into a less toxic form (NO3-), which creates a better water quality for the development of ornamental fishes in aquarium tank. This experiment was carried out to evaluate the efficiency of environmental quality by supplementation of sand and live rock in aquarium tank. There were two treatments with rock and sand supplement to the bottom of the tanks (NT1) and tanks without rock and sand added (NT2). There were 3 replicates for each treatment and the experiments were carried out in ten weeks. Results showed that sand and live rock could improve water quality and play as good place for fish and other creature hiding and reduce the water used. Water temperatures were 28.69oC (NT1) and 28.80oC (NT2), pH was about 8.13, salinity ranged from 34‰ to 35‰ in both treatments. NH4+was 0.035 ± 0.003 mgN/ml in the two treatments. After 2 weeks of putting fish in the experimental tanks NO2- values were 0.023 mgN/l (in treatment NT2) and 0.018 mgN/l (in treatment NT1). The average values of NO2- for whole experimental period in the NT1 and NT2 were 0.008 ± 0.001 mgN/l and 0.010 ± 0.002 mgN/l, respectively (P = 0.061). NO3- values were not significantly different between the two treatments (P 0.05). However, the ratio of NO2-/NO3- in NT1 was lower compared to this value in NT2 (NT1: 0.15 ± 0.03% and NT2: 0.39 ± 0.09%, P = 0.018). This paper provides an important reference to help aquarists to design and control their ornamental aquarium tank suitably.Hệ thống lọc sinh học là nơi sinh sống của các vi khuẩn ni trat hóa - các vi khuẩn có vai trò chuyển hóa ni tơ thải ra từ cá và vật nuôi ở dạng độc (NH4+/NH3) sang dạng ít độc hơn (NO3-). Các vi khuẩn này sống bám trên các giá thể như đá và cát. Thí nghiệm đánh giá hiệu quả cải thiện chất lượng môi trường của việc bổ sung nền đáy cát và đá vào bể nuôi cá cảnh biển. Thí nghiệm bao gồm 2 nghiệm thức. Nghiệm thức 1 (NT1): Bổ sung đá sống và cát vào bể nuôi và nghiệm thức 2 (NT2): Bể nuôi có đáy trần. Mỗi nghiệm thức có kết quả thí nghiệm cho thấy, bổ sung nền đáy cát và đá sống vào bể nuôi đã đem lại hiệu quả cải thiện rõ rệt các muối dinh dưỡng nitơ từ dạng có độc hại cho vật nuôi sang dạng ít độc hơn. Nhiệt độ 28,69oC (NT1) và 28,80oC (NT2), pH xấp xỉ 8,13 và độ mặn dao động 34–35‰ ở cả 2 nghiệm thức thí nghiệm. NH4+ở cả 2 nghiệm thức có giá trị trung bình 0,035 ± 0,003 mgN/ml. Sau 2 tuần thả cá, hàm lượng NO2- 0,023 mgN/l (NT2) và 0,018 mgN/l (NT1). NO2- trung bình ở NT1 và NT2 lần lượt là 0,008 ± 0,001 mgN/l và 0,010 ± 0,002 mgN/l (P = 0,061). Hàm lượng NO3- giữa 2 nghiệm thức không khác nhau có ý nghĩa thống kê (P 0,05). Tuy nhiên, tỷ lệ NO2-/NO3- ở NT1 nhỏ hơn có ý nghĩa thống kê so với NT2 (NT1: 0,15% ± 0,03% và NT2: 0,39% ± 0,09%, P = 0,018). Ngoài ra việc bổ sung nền đáy cát và đá sống tạo sinh cảnh và tạo nơi ẩn nấp cho cá. Đồng thời cũng giúp hạn chế thay nước và vệ sinh nền đáy của bể nuôi có đáy cát và đá sống. Kết quả nghiên cứu là cở sở khoa học quan trọng để bổ sung đá sống và cát trong bể nuôi cá cảnh tại Bảo tàng Hải dương học
ĐÁNH GIÁ TỔNG HỢP VÀ ĐỊNH HƯỚNG PHÁT TRIỂN HỆ THỐNG 50 ĐẢO VEN BỜ BẮC BỘ VIỆT NAM ( CÓ DIỆN TÍCH TỪ 1KM2 TRỞ LÊN)
Get PDFVietnam has about 2,773 islands located in the coastal areas of different seas, including around 100 islands with an area of 1 km2 or more (these islands are large enough for socio-economic development). Northern coastal area has 50 islands with an area of 1 km2 or more, distributed in two provinces Quang Ninh (47 islands), Hai Phong (3 islands). According to a combined assessment of the potential and position of 50 Northern coastal islands for the purpose of economic development, defense and security, 9 islands have been recognized as having the capability of defense and economic development; 6 islands have the advantages of economic development and national defense; 16 islands have the primary function of economic development and 19 islands should focus on their advantages of tourism and agroforestry, which will also be considered as a reserved resource for future island economic development.Tóm tắt: Việt Nam có khoảng 2773 hòn đảo với diện tích 1721 km2, phân bố ở ven bờ các vùng biển khác nhau, trong đó có khoảng 100 đảo có diện tích từ 1km2 trở lên (là các đảo có diện tích đủ lớn để phát triển kinh tế xã hội). Ven bờ Bắc Bộ là nơi tập trung nhiều đảo nhất (2321 đảo), chiếm tới 83,7% tổng số đảo và 48,9% tổng diện tích đảo ven bờ của cả nước và có tới 50 đảo có diện tích từ 1km2 , phân bố ở 2 tỉnh Quảng Ninh (47 đảo), Hải Phòng (3 đảo). Trên cơ sở đánh giá tổng hợp tiềm năng và vị thế của 50 đảo ven bờ Bắc Bộ cho các mục đích phát triển kinh tế và quốc phòng an ninh, đã xác định được 9 đảo có chức năng quốc phòng và phát triển kinh tế; 6 đảo có ưu thế chức năng phát triển kinh tế kết hợp với quốc phòng; 16 đảo có chức năng chủ yếu phát triển kinh tế và 19 đảo có thể khai thác lợi thế để phát triển du lịch và nông lâm nghiệp, cũng như được coi là nguồn lực dự trữ cho phát triển kinh tế biển đảo sau này
Theoretical basis for reasonable population distribution in Tho Chu archipelago
Get PDFTho Chu archipelago is one of administrative units of Kien Giang province, Hon Nhan- one of its islands - is selected to become A1 base point of baseline for Vietnam territorial waters. If Tho Chau district is established, it will contribute to identifying sovereignty of Vietnam Southwest sea area following the United Nations Convention on the Law of the Sea, creating favourable conditions for islands’ socio-economic development, developing culture, enhancing effects of administration work and life quality of population in this island, firmly protecting sea border, securing island and sea sovereignty… However, the establishment of Tho Chu district appears in the context of streamlining administrative apparatus and limitation of capital for infrastructure construction in district level. This article focuses on the analysis of some factors affecting a reasonable population distribution in order to meet the requirement of building the Tho Chu into a district-level administrative unit in Kien Giang province
Simulation of suspended sediment and black carbon transport in surface water layer of Ha Long bay
Get PDFDelft3D model employed to simulate the distribution and transport of suspended sediment and black carbon in Ha Long bay shows outcomes meeting with results from previous experiment studies. In the rainy season, suspended matter in surface layer is mainly in waters of western and southwestern Cat Ba island regions, and from Cua Luc toward the south nearshore areas with concentration of 50–130 g/m3. The concentration of suspended setdiment in the waters from Cua Luc to the north nearshore area is from 20 g/m3 to 50 g/m3 and that of offshore areas is 2–20 g/m3. In the dry season, the average concentrations of suspended matter are lower, approximately 110–150 g/m3 compared to the rainy season. In the rainy season, the total particulate carbon in surface layer is 0.0016–0.0028 kg/m3 and in the dry season, it ranges from 0.0001–0.005 kg/m3