Search

In searching for a maximum power point (MPP) using a DC boost converter for photovoltaic (PV) energy conversion systems, we realised that the fast and accurate way to find the suitable duty ratio value is the core problem to enhance the energy conversion efficiency of the PV system. Under uniform irradiation, the panels will generate the same values, so they have only one peak on the P-V curve; conventional MPP tracking methods easily obtain this MPP. However, under partial shading conditions, many peaks are created, traditional MPP tracking methods can fall into the local MPP, and this issue will cause energy loss and reduce PV energy conversion efficiency. To avoid this disadvantage, this paper proposes a hybrid method (HM) by combining the improved chicken swarm optimisation (CSO) method and the incremental conductance (InC) algorithm for a DC standalone PV energy conversion system. In this hybrid method, the improved CSO modified approach is used to search the global region, and the InC algorithm is responsible for capturing the top of this global region. MATLAB simulation and experimental results were performed to demonstrate that the proposed method has achieved the global MPP under uniform solar irradiance and partial shadow effects.

Astaxanthin (AX) is a natural compound that regulates lipid metabolism in the liver, specifically in reducing hepatosteatosis. To the increment in Non-Alcoholic Fatty Liver Diseases (NAFLD) ratio and its burdens, prevention/treatment should address the world health problem. This study aimed to evaluate the ability of AX and its prolonged effects on the physiology of mice fed a high-fat diet. Mice fed with a high-fat diet (HFD) (n=12) were orally given AX at a dosage of 30 mg/kg body weight/day for 16 weeks, followed by eight weeks of AX termination, along with other CTL (normal chow diet) and HFD only group. At four time points of 8, 12, 16, and 24 weeks of the trial, three mice from each group were randomly dissected to collect blood, liver, and adipose tissue samples. AX given through oral gavage showed an excellent factor for maintaining total cholesterol, triglyceride, glucose, and Low-density Lipoprotein cholesterol (LDL-c). Moreover, AX did have impacts on preventing dyslipidemia in mice fed with HFD. Unexpectedly, AX supplied group caused excess weight gain in mice, shown in higher average body weight than HFD fed group. However, all the AX effects wore off after 8 weeks of termination. AX was a good player for liver and plasma lipid homeostasis, but not for weight control. Taken together, AX was a potential compound for preventing hepatosteatosis and hyperlipidemia, but not for controlling weight in mice fed with a HFD.

Quantum dots (QDs) have the potential to be used as a marker in research and supporting for medical treatment because of their unique optical and electronic properties such as size-tuneable light emission, narrow emission, high photostability, etc. With the goal of applying for biomarkers, QDs are often attached with antibodies. In order to simplify the binding process, we experimented to attach adaptor protein, namely protein A/G to CdSe/ZnS QDs covered by 3-mercaptopropionic acid (MPA). 80.7 % and 51.2 % of protein A/G at the concentration of 60 μg/mL and 20 μg/mL, respectively, conjugated with QDs in phosphate buffer saline (PBS) without supporting of N-Ethyl-N’-(3dimethylaminopropyl) carbodiimide/N-hydroxysuccinimide (EDC/NHS). After attaching to protein A/G, anti-pan T antibody could recognize and visualize Jurkat T cells. In conclusion, protein A/G was conjugated successfully on QDs and initially support for application in cell labeling.

In recent years, the heavy transport industry has been developing strongly, the transportation of super long and overweight packages is more advantageous due to modern transportation systems applying the achievements and development of technology. The leading trailer manufactors in the world such as: Cometto, Nicolas, Kamag, and Goldhofer… increasingly research and manufacture for this heavy transport industry. In Vietnam, leading transport companies have invested in self-propelled tractors from Cometto (Italy) to transport these goods. However, during operation, safety has been revealed. Therefore, in order to further enhance the safety of the entire system when transporting large economic parcels to the required location, a method is proposed that the throttle valve have been attached to appropriate position in the hydraulic pump system. The efficiency of throttle assembly is verified in practice when applying this improved trailer system for transporting the drilling rigs up to 3,200 tons in Vietnam.

Protection of the living environment for sustainable development is a concern of mankind. In particular, reducing CO2 emissions is the top criteria. A number of technologies that include a method of improving fossil fuel consumption effectiveness have been introduced into new automobiles in order to limit the negative effects caused by CO2. In this paper, new technological solutions will be proposed. They are combined in a novel method in order to improve vehicle engine performance, to improve ignition and air return systems and to reduce friction between vehicle and environment when it is moving. The propsed method is applied into a new implemented vehicle for Eco Mileage Challenge (EMC) 2019 which is organized annually by Honda Vietnam Compapy. All tests and tournament results of 240 km per liter of RON98 gasoline in average prove that the propsed method is feasible and effective in fuel savings.

Background Recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) is a glycoprotein that has been approved by the FDA for the treatment of neutropenia and leukemia in combination with chemotherapies. Recombinant hGM-CSF is produced industrially using the baker’s yeast, Saccharomyces cerevisiae, by large-scale fermentation. The methylotrophic yeast, Pichia pastoris, has emerged as an alternative host cell system due to its shorter and less immunogenic glycosylation pattern together with higher cell density growth and higher secreted protein yield than S. cerevisiae. In this study, we compared the pipeline from gene to recombinant protein in these two yeasts. Results Codon optimization in silico for both yeast species showed no difference in frequent codon usage. However, rhGM-CSF expressed from S. cerevisiae BY4742 showed a significant discrepancy in molecular weight from those of P. pastoris X33. Analysis showed purified rhGM-CSF species with molecular weights ranging from 30 to more than 60 kDa. Fed-batch fermentation over 72 h showed that rhGM-CSF was more highly secreted from P. pastoris than S. cerevisiae (285 and 64 mg total secreted protein/L, respectively). Ion exchange chromatography gave higher purity and recovery than hydrophobic interaction chromatography. Purified rhGM-CSF from P. pastoris was 327 times more potent than rhGM-CSF from S. cerevisiae in terms of proliferative stimulating capacity on the hGM-CSF-dependent cell line, TF-1. Conclusion Our data support a view that the methylotrophic yeast P. pastoris is an effective recombinant host for heterologous rhGM-CSF production. Electronic supplementary material The online version of this article (doi:10.1186/s13104-017-2471-6) contains supplementary material, which is available to authorized users.

This paper presents a solution for globally optimized trajectory planning with respect to the shortest distance for multicopters, particularly in two dimensional space to avoid restricted airspaces. The presented approach relies on a sparse visibility-graph, a classic roadmap of combinatorial planning in computer geometry which is able to retain the complete-feature of the algorithm. The set of restricted airspaces is seen as a set of obstacles and to build a sparse visibility-graph based on tangents between obstacles, the proposed method takes O(n + h2logn), in which h is the number of obstacles with n vertices in total. The developed technique here outperforms the original method, which is demonstrated by without the data structure of balanced tree and without trigonometric functions, whereas still keeping the computation and storage complexity unchanged as previous studies. Through extensive experimental results, with a real multicopter system, the approach indicates to be efficient, feasible and straightforward to apply into practice.