ẢNH HƯỞNG CỦA NỀN ĐÁY CÁT VÀ ĐÁ SỐNG LÊN CHẤT LƯỢNG MÔI TRƯỜNG BỂ NUÔI CÁ CẢNH BIỂN

Marine 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

Investigation of anti-inflammatory lignans from the leaves of Symplocos sumuntia Buch-Ham ex D Don (Symplocaceae)

Purpose: To investigate the anti-inflammatory activity of Symplocos sumuntia Buch.-Ham. ex D. Don and identify the main secondary metabolites responsible for this effect.Methods: The in vitro anti-inflammatory activity of the plant extract and isolated compounds was determined in terms of the ability to inhibit the production of nitric oxide (NO), and expressions of iNOS and COX-2 proteins in RAW264.7 cells stimulated by lipopolysaccharide (LPS). Compounds were isolated and identified by spectroscopic methods.Results: The methanol extract of S. sumuntia leaves showed strong inhibitory effects on nitric oxide (NO) production and expression of iNOS and COX-2 in LPS-induced RAW264.7 cells. A phytochemical assay-guided fractionation of the methanol extract of S. sumuntia leaves led to the isolation of four lignans which are arctigenin (1), matairesinol (2), monomethylpinoresinol (3) and pinoresinol (4). These compounds were identified for the first time from S. sumuntia. All four compounds inhibited the production of nitric oxide (NO), with arctigenin showing the most potent activity with half-maximal inhibitory concentration (IC50) value of 4.08 μM.Conclusion: S. sumuntia is a promising source of anti-inflammatory agents, which may clarify to the therapeutic use of this plant in Vietamese traditional medicine.Keywords: Symplocos sumuntia, Symplocos caudata, Lignan, Arctigenin, Anti-inflammator

Effects of dietary Mannan oligosaccharide (MOS) on grown, survival rate, intestinal morphology and blood cell count of the golden trevally fish (Gnathanodon specious)

The golden trevally fishes (Gnathanodon specious) (2.19 ± 0.23 g) were cultured in glass tanks with density of 20 fishes/tank and they were fed supplemental diets of different MOS concentrations (0; 0.2; 0.4 and 0.6%) for 90 days. Collected data included growth rate, survival rate and some hematological characteristics of this fish. The results demonstrated that MOS supplementation did not affect growth performance, erythrocyte density and blood cell size, however the survival rate was significantly increased. On the other hand, the total number of white blood cells (BC) on the 60th day in the fish fed with MOS supplements (5.78–6.96 × 104TB/mm3) was higher than that in the control group (only 5.43 × 104TB/mm3) with the largest total leukocytes (6.96 ± 0.50 × 104TB /mm3) at 0.2% MOS (p 0.05)

ẢNH HƯỞNG CỦA VITAMIN E BỔ SUNG VÀO THỨC ĂN ĐẾN HIỆU QUẢ SINH SẢN, CHẤT LƯỢNG TRỨNG VÀ ẤU TRÙNG CÁ KHOANG CỔ NEMO (Amphiprion ocellaris (CUVIER, 1830))

This study was carried out to determine the effects of vitamin E (a-tocopherol) in five levels (0, 125, 250, 375 and 500 mg vitamin E/kg feed) in broodfish diets on reproductive, egg and larval quality parameters of clownfish (Amphirion ocellaris). Each treatment was repeated in triplicate and the supplemental feeding trial was arranged for 13 months. The result showed that there were no significant differences in re-maturation and spawning periods, spawning frequency, fecundity, egg diameter and larval size of Nemo fish observed between the treatments. However, diets supplemented with vitamin E positively influenced the rate of egg loss, hatching rate of egg and survival rate of the 3 days post hatch. The overall result of this experiment indicated that the optimum vitamin E requirement of clownfish for reproductive performance was 375 mg vitamin E/kg feed.Thí nghiệm được thực hiện nhằm xác định ảnh hưởng của vitamin E (0, 125, 250, 375 và 500 mg/kg thức ăn) được bổ sung trong thức ăn cá bố mẹ đến các chỉ số sinh sản, chất lượng trứng và ấu trùng cá khoang cổ Nemo (Amphiprion ocellaris). Mỗi nghiệm thức được lặp lại 3 lần và thí nghiệm được tiến hành trong 13 tháng. Kết quả đã cho thấy thời gian tái thành thục và sinh sản, tần suất sinh sản, sức sinh sản thực tế, đường kính trứng và kích thước ấu trùng không bị ảnh hưởng bởi chế độ ăn bổ sung vitamin E ở các mức khác nhau. Tuy nhiên, chế độ ăn có bổ sung vitamin E đã ảnh hưởng tích cực đến tỷ lệ hao hụt của trứng, tỷ lệ trứng nở và tỷ lệ sống của ấu trùng 3 ngày tuổi. Kết quả nghiên cứu chỉ ra rằng nhu cầu vitamin E tối ưu của cá khoang cổ Nemo đạt được hiệu quả sinh sản là 375 mg vitamin E/kg thức ăn

Cyanide detoxification efficiency of injection and soak of hydroxocobalamin, sodium nitrite and sodium thiosulfate for sea water ornamental fish

The Oceanographic Museum offers interesting exhibits of several marine lives for tourist sightseeing and entertainment. These sea water ornamental fish are all caught in the wild. However, its health can be affected by cyanide poisoning during human fishing. Depending on the level of cyanide poisoning, fish can die after one and two weeks that caused economic damages for the museum. The present study is concerned with results of cyanide detoxification by using direct injection into cinnamon clownfish or soak of hydroxocobalamin, sodium nitrite and sodium thiosulfate with the aim of improving the health, survival and life time for fish, contributing to increasing economic efficiency for the Oceanographic Museum

Bringing social and cultural considerations into environmental management for vulnerable coastal communities: Responses to environmental change in Xuan Thuy National Park, Nam Dinh Province, Vietnam

This paper elaborates the importance of considering social and cultural factors within management responses to environmental change in coastal areas. The case study taken is Xuan Thuy National Park in Nam Dinh Province, Vietnam. This is a marginalised coastal area where rising sea levels, increasing storm surges and saltwater intrusion place pressure on coastal ecosystems, yet where communities continue to rely on these same ecosystems for agriculture- and aquaculture-related livelihoods. We interview stakeholders in Xuan Thuy National Park, connecting these with a narrative review of existing research into social and environmental change in the park to understand research gaps and challenges for vulnerable coastal areas like the Nam Dinh coast. Based on our findings, we suggest that whilst the effects of a changing environment on physical health and economic activity are increasingly well understood, effects on wellbeing and social relations can be even more immediate and profound in daily living. In turn, we argue environmental management has a crucial role to play not only for ecosystem-based adaptation, but also in sustaining wellbeing and allowing culturally meaningful practices to continue – especially in coastal regions where changes can be even more intense and immediate. However, we caution that whilst techno-scientific solutions grounded in environmental management do have significant potential in reducing impacts of extreme events and slower-onset environmental changes, they must not divert attention away from structural issues that can make some people or areas more vulnerable in the first instance

Safety and efficacy of fluoxetine on functional outcome after acute stroke (AFFINITY): a randomised, double-blind, placebo-controlled trial

Background Trials of fluoxetine for recovery after stroke report conflicting results. The Assessment oF FluoxetINe In sTroke recoverY (AFFINITY) trial aimed to show if daily oral fluoxetine for 6 months after stroke improves functional outcome in an ethnically diverse population. Methods AFFINITY was a randomised, parallel-group, double-blind, placebo-controlled trial done in 43 hospital stroke units in Australia (n=29), New Zealand (four), and Vietnam (ten). Eligible patients were adults (aged ≥18 years) with a clinical diagnosis of acute stroke in the previous 2–15 days, brain imaging consistent with ischaemic or haemorrhagic stroke, and a persisting neurological deficit that produced a modified Rankin Scale (mRS) score of 1 or more. Patients were randomly assigned 1:1 via a web-based system using a minimisation algorithm to once daily, oral fluoxetine 20 mg capsules or matching placebo for 6 months. Patients, carers, investigators, and outcome assessors were masked to the treatment allocation. The primary outcome was functional status, measured by the mRS, at 6 months. The primary analysis was an ordinal logistic regression of the mRS at 6 months, adjusted for minimisation variables. Primary and safety analyses were done according to the patient's treatment allocation. The trial is registered with the Australian New Zealand Clinical Trials Registry, ACTRN12611000774921. Findings Between Jan 11, 2013, and June 30, 2019, 1280 patients were recruited in Australia (n=532), New Zealand (n=42), and Vietnam (n=706), of whom 642 were randomly assigned to fluoxetine and 638 were randomly assigned to placebo. Mean duration of trial treatment was 167 days (SD 48·1). At 6 months, mRS data were available in 624 (97%) patients in the fluoxetine group and 632 (99%) in the placebo group. The distribution of mRS categories was similar in the fluoxetine and placebo groups (adjusted common odds ratio 0·94, 95% CI 0·76–1·15; p=0·53). Compared with patients in the placebo group, patients in the fluoxetine group had more falls (20 [3%] vs seven [1%]; p=0·018), bone fractures (19 [3%] vs six [1%]; p=0·014), and epileptic seizures (ten [2%] vs two [<1%]; p=0·038) at 6 months. Interpretation Oral fluoxetine 20 mg daily for 6 months after acute stroke did not improve functional outcome and increased the risk of falls, bone fractures, and epileptic seizures. These results do not support the use of fluoxetine to improve functional outcome after stroke

Study on the transient response of lower limb rehabilitation actuator using the pneumatic cylinder

A lower limb rehabilitation device was designed using the compressed air cylinder in order to answer the particular request in Vietnam. This paper is presenting the results of a study of the device response. Dynamic equation of the actuator and equations of the proportional valve have been established. The relationship between the input signal and the output signal of the actuator was derived. Inventor® software was used to design the mechanical structure of the device. Matlab® software was used to calculate the parameters values of the PID controller by simulating the response of the actuator. The results show that the response time of both knee drive and hip drive mechanisms are 8 seconds while the overshoot of both knee drive and hip drive mechanisms are 1%. Moreover, the starting torque of the knee drive mechanism is 17 Nm, and the starting torque of the hip drive mechanism is 35 Nm. The simulation results show that the PID controller gives a fast response time and a low overshoot

Waffle-inspired hydrogel-based macrodevice for spatially controlled distribution of encapsulated therapeutic microtissues and pro-angiogenic endothelial cells

Macro-encapsulation systems for delivery of cellular therapeutics in diabetes treatment offer major advantages such as device retrievability and high cell packing density. However, microtissue aggregation and absence of vasculature have been implicated in the inadequate transfer of nutrients and oxygen to the transplanted cellular grafts. Herein, we develop a hydrogel-based macrodevice to encapsulate therapeutic microtissues positioned in homogeneous spatial distribution to mitigate their aggregation while concurrently supporting an organized intra-device network of vascular-inductive cells. Termed Waffle-inspired Interlocking Macro-encapsulation (WIM) device, this platform comprises two modules with complementary topography features that fit together in a lock-and-key configuration. The waffle-inspired grid-like micropattern of the "lock" component effectively entraps insulin-secreting microtissues in controlled locations while the interlocking design places them in a co-planar spatial arrangement with close proximity to vascular-inductive cells. The WIM device co-laden with INS-1E microtissues and human umbilical vascular endothelial cells (HUVECs) maintains desirable cellular viability in vitro with the encapsulated microtissues retaining their glucose-responsive insulin secretion while embedded HUVECs express pro-angiogenic markers. Furthermore, a subcutaneously implanted alginate-coated WIM device encapsulating primary rat islets achieves blood glucose control for 2 weeks in chemically induced diabetic mice. Overall, this macrodevice design lays foundation for a cell delivery platform, which has the potential to facilitate nutrients and oxygen transport to therapeutic grafts and thereby might lead to improved disease management outcome.Agency for Science, Technology and Research (A*STAR)Ministry of Education (MOE)Nanyang Technological UniversityPublished versionThis work was supported by the Singapore Ministry of Education (Academic Research Tier 1 Grant, award RG51/ 18 (S)), NTUitive (GAP Fund, award NGF-2019-07-024), and the Agency for Science, Technology and Research of Singapore (A*STAR) (Manufacturing, Trade and Connectivity Individual Research Grant, award M21K2c0115). Chi H. L. Pham was supported by the NTU Research Scholarship for her doctoral study. Nam M. Tran was supported by the NTU-VinGroup Graduate Scholarship for his doctoral study

Study on the ankle rehabilitation device

This study developed an ankle rehabilitation device for post-stroke patients. First, the research models and dynamic equations of the device are addressed. Second, the Sliding Mode Controller for the ankle rehabilitation device is designed, and the device's response is simulated on the software MATLAB. Third, the ankle rehabilitation device is successfully manufactured from aluminum and uses linear actuators to emulate dorsiflexion and plantarflexion exercises for humans. The advantages of the device are a simple design, low cost, and mounts onto rehabilitative equipment. The device can operate fast through experiments, has a foot drive mechanism overshoot of 0°, and a maximum angle error of 1°. Moreover, the rehabilitation robot can operate consistently and is comfortable for stroke patients to use. Finally, we will fully develop the device and proceed to clinical implementation