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Dyslipidemia substantially contributes to the risk of cardiovascular diseases. The polyherbal formulation has been a traditional therapeutic strategy used to treat dyslipidemia. This study was designed to evaluate the effects of a novel herbal medicine called “GANMO” on an experimental animal model with endogenous dyslipidemia and exogenous dyslipidemia. In the endogenous hyperlipidemia model, rats were previously treated with GANMO tablets and intraperitoneally injected with poloxamer 407 to induce hyperlipidemia. In the exogenous hyperlipidemia model, rats were given oral administration of oil-cholesterol mixture and GANMO for 4 consecutive weeks. Serum lipid profiles were assessed at all experimental animals. In both models, GANMO at both doses significantly decreased the serum total cholesterol (TC) level and non-high-density lipoprotein (HDL) cholesterol level as compared with the model group. HDL cholesterol levels increased in rats with high doses of GANMO compared to those with low doses. GANMO at both doses substantially reduced TG level in the endogenous hyperlipidemia model. In conclusion, GANMO tablets posed a positive effect on serum lipid modulations in dyslipidemia models.

A rapid scoping review of the effectiveness and safety of drug treatments currently under investigation for COVID-19 or that have been previously tested in SARS or MERS.

This is the preregistration of the protocol for a scoping review on Initiatives to improve coverage, quality, financial protection, and financial sustainability in long-term care.

International audience; We investigate the decoding of the sum of Gabidulin codes. We show that there exists a probabilistic polynomialtime decoder up to some bound. We then give some potential applications of constructing and decoding a sum of Gabidulin codes. This approach can lead to a new insight in designing rank-metric based cryptographic schemes.

We studied the development and persistence of neutralizing antibodies against SARS-CoV-2 ancestral strain, and Delta and Omicron (BA.1 and BA.2) variants in Vietnamese healthcare workers (HCWs) up to 15 weeks after booster vaccination. We included 47 HCWs, including group 1 (G1, N = 21) and group 2 (G2; N = 26) without and with breakthrough Delta variant infection before booster immunization, respectively). The study participants had completed primary immunization with ChAdOx1-S and booster vaccination with BNT162b2. Neutralizing antibodies were measured using a surrogate virus neutralization assay. Of the 21 study participants in G1, neutralizing antibodies against ancestral strain, Delta variant, BA.1, and BA.2 were (almost) abolished at month 8 after the second dose, but all had detectable neutralizing antibodies to the study viruses at week 2 post booster dose. Of the 26 study participants in G2, neutralizing antibody levels to BA.1 and BA.2 were significantly higher than those to the corresponding viruses measured at week 2 post breakthrough infection and before the booster dose. At week 15 post booster vaccination, neutralizing antibodies to BA.1 and BA.2 dropped significantly, with more profound changes observed in those without breakthrough Delta variant infection. Booster vaccination enhanced neutralizing activities against ancestral strain and Delta variant compared with those induced by primary vaccination. These responses were maintained at high levels for at least 15 weeks. Our findings emphasize the importance of the first booster dose in producing cross-neutralizing antibodies against Omicron variant. A second booster to maintain long-term vaccine effectiveness against the currently circulating variants merits further research.

Hiệp định đối tác kinh tế toàn diện khu vực (Regional Comprehensive Economic Partnership - RCEP) được ký kết ngày 15/11/2020, sau 8 năm đàm phán, là Hiệp định thương mại tự do (Free Trade Agreement - FTA) lớn nhất thế giới với sự tham gia của 10 nước thành viên ASEAN và 5 quốc gia gồm: Australia, Trung Quốc, Nhật Bản, Hàn Quốc và New Zealand. Đến cuối lộ trình, giai đoạn năm 2035 - 2040, Việt Nam sẽ xóa bỏ thuế quan với khoảng 85,6 - 89,6% số dòng thuế với các nước đối tác và các nước đối tác xóa bỏ thuế quan cho Việt Nam trong khoảng 90,7 - 92% số dòng thuế. Bài báo so sánh thuế nhập khẩu của Việt Nam và thuế nhập khẩu của các nước (trong RCEP) từ Việt Nam và so sánh với biểu thuế của các FTA mà Việt Nam đã tham gia trực tiếp hoặc thông qua ASEAN đối với các sản phẩm chính của Tập đoàn Dầu khí Việt Nam (PVN) và các đơn vị thành viên gồm: xăng dầu, LPG, polypropylene (PP), urea, NPK, xơ, sợi. Từ đó, nhận diện cơ hội và thách thức trong hoạt động kinh doanh các sản phẩm này khi tham gia vào Hiệp định RCEP.

In this paper, a nanofluid-based solar collector duct equipped with baffles is examined numerically. Baffles are located on the back plate to guide nanofluid flow toward absorber plate for heat transfer enhancement purposes. Cu-water nanofluid with fixed flow rate and concentration in the baffled duct are investigated for thermohydraulic mechanisms. Baffles with different inclination angles, heights and pitches are considered in this study. Numerical simulations are performed using Ansys fluent software with verified results compared to those of an experiment in the literature. The results show that the baffle angle 60° causes the lowest thermohydraulic performance. Because in the angle range of 30 to 60° the heat transfer is less variable while the pressure loss increases sharply. At the baffle pitch of 40 mm, there is no reattachment point at the non-heated surface. At the angle of 90°, three eddies are formed around a baffle. The slope linear regression analysis yields that baffle height has the strongest effects on thermohydraulic performance followed by baffle pitch and baffle angle. Nanofluid pressure loss respectively increases with baffle height and baffle angle at the rate of 0.463675 and 0.0049607 while absorber plate temperature respectively decreases with the baffle height and baffle angle at the rate of -0.176746 and -0.001377. Flow patterns and isotherms of all the cases examined are presented and analyzed in this study.

This paper presents the distribution features of observed meteorological parameters in Truong Sa archipelago area including wind, tropical cyclone, and average values of solar radiation, air temperature, air humidity, rainfall. Observed data were collected from Truong Sa island hydro-meteorological station. In particular, data of tropical cyclones affecting Truong Sa archipelago area were collected from the websites http://www.jma.go.jp/jma/jma-eng/jma-center/(Japan). Study results show that the main meteorological parameters in Truong Sa archipelago area are affected by solar radiation and monsoonal wind regimes in East Asia region which are Northeast monsoon occurring from November to April and Southwest monsoon occurring from June to September. Transition periods are May and October. Tropical cyclones occur mainly in November–December, maximum wind speed was 64 m/s in typhoon HAIYAN (November 2013). The highest average solar radiation occurs in April (277 hours), the lowest in January (181 hours). The highest average air temperature occurs in April (29.5oC), the lowest in January (26.6oC). The highest average rainfall occurs in November (341 mm), the lowest in March (62 mm). The highest average air humidity occurs in November–December (85%), the lowest in April–May (79%). The highest average water evaporation occurs in March (129 mm), the lowest in December (87 mm).

In the trends of sustainable development and environmental protection, reducing greenhouse gas emissions and utilizing energy sources are feasible solutions. In this study, Aspen HYSYS-based performance simulations for LNG-fired power plants with CO2 capture and storage using cryogenic and amine technologies were conducted to compare and evaluate. LNG cold energy is employed in liquefied CO2 process. Waste heat from exhaust gas of a gas turbine was powered for steam cycle or stripper column. The results showed that the thermal power generation efficiency of the amine system is lower than that of the cryogenic system, however the excessive gasification of LNG in the MEA system is much lower than that of a cryogenic system. The CO2 mass fraction in recovered liquid of the amine system is also higher than the other one. Multi-objective optimization using genetic algorithm (GA) is then carried out providing a set of optimum solution for investors and operators in balance of the excessive gasification of LNG and CO2 recovery rate.

Aim: To evaluate pain relief, anti-inflammatory and hypouricemic effects of GT1 tablets on experimental animals. Method: GT1 at the doses of 22.32 g/kg/day and 66.96 g/kg/day were evaluated for its analgesic effect in three models (hot plate, pain threshold, and acetic acid-induced writhing), its chronic anti-inflammatory effect in the granulomatous reaction model, and its hypouricemic effect in potassium oxonate-induced hyperuricemic mice. Acute anti-inflammatory effects of GT1 at the doses of 11.16 g/kg/day and 33.48 g/kg/day were evaluated in rats with two models: carrageenin-induced paw edema and peritonitis. Results: GT1 prolonged the temperature reaction time on the hot plate (22.73 s and 20.37 s at both doses of 22.32 g/kg and 66.96 g/kg, respectively, compared to 16.96 s in control group), reduced the number of acid acetic-induced writhing effects, decreased the weight of granulomas, and decreased the level of acid uric in blood and urine (p < 0.05). GT1 caused a significant reduction in paw edema after subplantar injection of carrageenan in rats (p < 0.05). Moreover, there was a substantial decline of GT1 at the dose of 11.16 g/kg/day in terms of the volume and the quantity of protein in the inflammation fluid of the peritonitis model (p < 0.05). Conclusion: GT1 at both doses of 11.16 g/kg/day and 33.48 g/kg/day posed acute anti-inflammatory effects on rats. GT1 at both doses of 22.32 g/kg/day and 66.96 g/kg/day exerted analgesic, chronic anti-inflammatory and hypouricemic effects on mice.

Co To is an island of the Co To district in Quang Ninh province with an area of about 18 km2. Average rainfall on the island is 1,738.8 mm/yr, evaporation is 925 mm/yr. On the island, there are some small streams but they are temporary flow in the rainy season, there is not any natural lakes. There are 2 aquifers. The Quaternary aquifer (q) is distributed in a low terrain with area of about 9 km2, thin thickness and saline water is in about half of the area, so it does not make sense for water supply. The fissured aquifer of the ocdovic-silua (o-s) formation is distributed in the high terrain with an area of about 9 km2, this is low potential water layer. The flow rate in the boreholes in the fractured zone due to tectonic activity can be 1–1.5 l/s, it can satisfy small-scale water supply. Potential groundwater reserve of Co To island is 6,472 m3/day, exploitable reserve is 1941 m3/day, exploited reserve level at C1 range is 1,144 m3/day. This can satisfy the water demand for the living of people on the island today. Small-scale groundwater exploitation in the island has just been beginning, but it has the prospect of replication and at the same time there must be reasonable measures to protect and develop water resources to ensure sustainable development and meet the larger water requirements in the future.

Photocatalytic nanotechnology is one of the techniques that brings many new breakthroughs since it possesses high potential for the supply of clean energy and the degradation of persistent organic pollutants in the environment. The drawback of photocatalytic materials such as TiO2, ZnO, V2O5 is the activation only under ultraviolet light. To extend the applicability of photocatalytic nanomaterials to a visible light region, recent research has focused on the modification of semiconducting photocatalysts. In this study, V2O5-MgO/TiO2 mixed oxide nanocomposites were synthesised via a sol-gel method by using polyvinyl alcohol as a gelling agent. The basic structural characteristics of nanocomposites were determined by analytical techniques such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), BET, energy dispersive x-ray (EDX), x-ray diffraction (XRD), infrared (IR) and ultraviolet-visible (UV–vis) spectroscopy. The results obtained from EDX and XRD analyses indicate that V2O5 and MgO particles with a size between 14.5 and 21.3 nm were formed and uniformly dispersed in TiO2 phases. Moreover, the effects of oxide weight ratios, illuminating conditions and reaction time on the photocatalytic activity of the nanocomposites were investigated via CO conversion with the input CO concentrations of 8000 ppm. Significantly, the V2O5-MgO/TiO2 nanocomposites were used for treating CO in motorcycle exhaust fumes. The efficiency of the process reached 82% for 10 min, indicating the potential applicability of the V2O5-MgO/TiO2 nanocomposites for the CO treatment of industrial emissions.

The use of molecular dynamics (MD) simulations has led to promising results to unravel the atomistic origins of adhesive wear, and in particular for the onset of wear at nanoscale surface asperities. However, MD simulations come with a high computational cost and offer access to only a narrow window of time and length scales. We propose here to resort to the discrete element method (DEM) to mitigate the computational cost. Using DEM particles with contact and cohesive forces, we reproduce the key mechanisms observed with MD, while having particle diameters and system sizes an order of magnitude higher than with MD. The pairwise forces are tuned to obtain a solid with reasonably approximated elastic and fracture properties. The simulations of single asperity wear performed with MD are successfully reproduced with DEM using a range particle sizes, validating the coarse-graining procedure. More complex simulations should allow the study of wear particles and the evolution of worn surfaces in an adhesive wear context, while reaching scales inaccessible to MD., Comment: 17 pages, 20 figures

Friction and wear occur at every interface between solid materials. In the design of mechanical devices, it is desirable to be able to quantify and control the amount of friction and wear, as well as predict their evolution with time. ``Tribology'' is the science looking at interactive surfaces in relative motion, which involves many phenomena such as friction, wear, lubrication, and corrosion. Phenomenological models can be used to make predictions on tribological behaviors (the Coulomb's friction law, for example), but they must be tuned with experimental values, that are not directly available when developing novel materials or surface treatments. From a scientific point of view, these models give little to no insight into the mechanisms involved. This thesis aims to enhance the current understanding of dry friction and wear at a more fundamental level. All surfaces are rough over a range of length scales, whether they are man-made or natural. When two rough surfaces are put into contact with each other, only a fraction of the total apparent area is actually in contact. To study friction and wear in this context, we must go down at the scale of the smallest asperities of the rough surfaces, where contact happens. The main goal of this thesis is to acquire an understanding of adhesive wear from the nanoscale, and establish a link with the larger scales. To do so, we start by working at the asperity scale, using analytical theories and molecular dynamics simulations to investigate the wear of several interacting micro-contacts. The elastic interactions enable the emergence of a wear regime featuring large wear volumes that are not observed when considering the micro-contacts in an isolated manner, predicting the existence of a severe wear regime. The emergence of severe wear is also found with rough contacts at a larger scale, solved using the boundary element method. To upscale the dynamical nanoscale processes of friction and wear uncovered during this thesis, a coarse-grained discrete element model was formulated. This model is capable of reproducing the adhesive wear mechanisms observed with molecular dynamics, and it can handle more complex situations involving the creation of third-body particles and a third-body layer. The temporal evolution of tribological interfaces is investigated using this model and with the help of physical experiments. We found that the wear process starts with the formation of small wear particles, whose size is dictated by the material properties. The particles grow and merge into a third-body layer, responsible for the macroscopic roughness and providing the sliding resistance. Finally, using some of the knowledge earned along the way, a practical case was investigated. The tribological influence of an oxide layer on silicon samples was assessed using experiments and numerical simulations. We found that the presence of the oxide layer reduces the wear rate of the protected piece, but increases the friction coefficient. While this thesis was restricted to the study of unlubricated adhesive wear, its founding principles and the developed tools could be used to look at abrasion and lubricated contacts.

In this paper we show that in the case where the public-key can be distinguished from a random code in Loidreau's encryption scheme, then Coggia-Couvreur attack can be extended to recover an equivalent secret key. This attack can be conducted in polynomial-time if the masking vector space has dimension 3, thus recovering the results of Ghatak., Comment: Long version of an article submitted at the conference WCC 2022

In 2005, Faure and Loidreau proposed a new rank-metric cryptosystem inspired from the Hamming metric scheme of Augot-Finiasz in 2003. In 2018, it was broken by the attack of Gaborit, Otmani and Kalachi. Recently, there are some attempts of repairing the Faure-Loidreau scheme, for example the work of Renner, Puchinger and Wachter–Zeh which is called LIGA. In this thesis, we also introduce a new cryptosystem so-called RAMESSES which is another repairing of Faure-Loidreau scheme. Besides, we also study about the recent attack of Coggia and Couveur in the Loidreau's cryptosystem (2017). Although they only propose an idea for a special case of the dimension of secret subspace, this attack can be generalized. In this thesis, we propose an analysis of Coggia-Couvreur attack on Loidreau’s rank-metric public-key encryption scheme in the general case. The last part is a study about the decoding of the sum of Gabidulin codes which is inspired from the work of Loidreau in 2005 "Welch-Berlekamp Like Algorithm for Decoding Gabidulin Codes". This work is also an attempt to repair the Loidreau's cryptosystem (2017) to avoid the Coggia-Couveur's attack., En 2005, Faure et Loidreau ont proposé un nouveau métrique rang cryptosystème inspiré du schéma métrique de Hamming d'Augot-Finiasz en 2003. En 2018, il a été attaqué par Gaborit, Otmani et Kalachi. Récemment, il y a eu quelques tentatives de réparation du schéma Faure-Loidreau, par exemple les travaux de Renner, Puchinger et Wachter-Zeh qui s'appelle LIGA. Dans cette thèse, on introduit également un nouveau cryptosystème appelé RAMESSES qui est une autre réparation du schéma de Faure-Loidreau. Par ailleurs, on étude également l'attaque récente de Coggia et Couveur sur le cryptosystème de Loidreau (2017). Bien qu'ils ne proposent qu'une idée pour un cas particulier de la dimension du sous-espace secret, cette attaque peut être généralisée. Dans cette thèse, on propose une analyse de l'attaque Coggia-Couvreur sur le schéma de chiffrement à clé publique en métrique rang de Loidreau dans le cas général. La dernière partie est une étude sur le décodage de la somme des codes de Gabidulin qui s'inspire du "Welch-Berlekamp Like Algorithm for Decoding Gabidulin Codes" de Loidreau en 2005. Ce travail est également une tentative de réparation du cryptosystème de Loidreau (2017) pour éviter l'attaque de Coggia-Couveur.

We report a flexible and noninvasive method based on field-effect transistors hybridizing semiconducting single-walled carbon nanotubes for monitoring the effects of histamine on Ca

Bathymetry mapping of coastal zones is one of the minimum requirements to serve related activities as marine management, transportation, construction and scientific application. However, the traditional method of direct measurement in the fields meets problems of time consuming, manpower and money. Applying remote sensing techniques to establish bathymetry in shallow water is an effective method to overcome the traditional problems. The objective of this study is to use VNREDSAT-1 data to map the bathymetry in a coastal region of Vietnam and Ninh Hai coast was selected as a case study in this research. The image was acquired on September 4th, 2013 and preprocessed through atmospheric correction using 6S model and sun glint removal by Hedley method. A total of 3,642 collected data points were divided into two parts, the first part of 2,810 points used to build up the model and the rest of 832 points for validation. The model used is based on multiple regression methods with four independent variables as four bands and a dependent variable as water depth. The results show that the models got high accuracy at the water depth from 10 m to 19 m with root mean square error of 1.03 m to 1.99 m and correlation coefficients of 0.72 to 0.74. This study demonstrates the capacity of VNREDSAT-1 in bathymetry mapping, and it would be an efficient tool for precisely mapping crude bathymetry in Vietnam.

Rip current is a relatively strong, narrow current flowing outward from the beach through the surf zone and presenting a hazard to swimmers. This paper presents some occurrence features of Rip current at main swimming beaches in Quang Nam province, Central Vietnam. Study results show that most of swimming beaches along Quang Nam province coast are directly opposed to open sea and strongly affected by swell. Therefore, Rip current system can occur at any time in the year with large dimension and intensity. During Northeast monsoon (November to March) beach morphology is considerably changed by strong wave action, thus the strongest rip current is formed. However, in this period careful swimmers can easily identify where that rip current occurs along the beach. During the transition period from Northeast monsoon to Southwest monsoon (April to May) wave energy is reduced, thus Rip current intensity is also decreased. During Southwest monsoon (June to August) wave energy is not strong and beach is accreted, therefore some Rip currents remain at reasonable morphology places along the beach. During the transition period from Southwest monsoon to Northeast monsoon (September to October) Rip current can occur at deep places along the beach with characteristics of narrow dimension, thus causing more danger to swimmer. Especially, dangerous rip current is caused by swell which comes from active region of tropical cyclone in open sea. In this period wave field in the nearshore region is not rough, thus most of swimmers are not cautious when swimming at dangerous rip current places.

According to statistics in Binh Thuan - Ninh Thuan provinces, there are 4 projects of dredging and recovering saline sand at estuaries such as La Gi, Ca Ty, Phan Ri Cua and Dong Hai. These projects use dredging plans by sand suction vessel and scraper bucket to scoop sand on barges, then sand is transferred to ships for exportation or used for levelling platform of urban buildings on the south bank of estuaries. The channel dredging process has changed and distributed the energy of waves, currents, tides, dynamics, incident wave fields, geological structures, topographic characteristics of the shore and bottom, thereby forming the new erosion - deposition process, affecting the shoreline in estuaries.

Objectives: To study the prevalence of drug resistance and genotype testing for HIV drug resistance on HIV/AIDS patients with first-line antiretroviral treatment failure at Dong Da Hospital, Hanoi, Vietnam. Patients and methods: Forty-seven patients in Dong Da Hospital, Hanoi, with confirmation of first-line antiretroviral therapy (ART) failure were enrolled in this study from June 2006 to December 2016. Both the protease and reverse transcriptase genes were amplified and sequenced using Trugene® HIV-1 Genotyping Kit and OpenGene® DNA system at the biomolecular laboratory of the National Institute of Hygiene and Epidemiology, Vietnam. The Stanford HIV database algorithm was used for interpretation of resistance data and genotyping. Results: Drug resistance mutations were 90.7% in patients with first-line treatment failure. Amongst patients with drug resistance mutation, 97.7% resisted to non-nucleoside reverse transcriptase inhibitors (NNRTIs), followed by nucleoside reverse transcriptase inhibitors (NRTIs, 95.3%) and protease inhibitors (PIs, 11.6%). Amongst the genetic mutations resistant to NNRTIs, G190S mutation was the highest (51.2%), K101HQ mutation was 39.5% and Y181I mutation was 34.9%. In genetic mutations to NRTIs, M184V mutation was 88.4%. In thymidine analogue mutations, K70R mutation was the most common (37.2%), followed by D67N, T215F and T69N mutations (27.9%, 27.9% and 25.6%, respectively). In genetic mutations in PIs, M36I and K20R mutations made up 9.3%. In NNRTIs, the prevalence of nevirapine resistance was 55.8%, and that of efavirenz resistance was 4.7%. In NRTIs, the ratio of lamivudine resistance was 93.0%, and that of zidovudine resistance was 9.3%. No lopinavir/ritonavir resistance was recorded. Conclusions: Drug resistance mutations in patients with first-line ART failure had a high prevalence of NNRTI and NRTI resistance but still susceptible to PIs.

This paper aims to identify the causes and sources of erosion and deposition at small estuaries in southern central Vietnam under human intervention. The jetty built at the Tam Quan river mouth (Binh Dinh Province, Vietnam) serves as the base for the study. After its completion at the end of 2009, the hydrodynamic and erosion-deposition processes in the region have been significantly altered. Inside the estuary, the waves are not influenced, but the currents are increased during the ebb tide period and decreased during the flood tide timeframe. During the southwest monsoon, the jetty could cause an increase in the deposition process in both frequency and area, whereas the erosion process tends to narrow the area and increase the frequency on the north coast. In contrast, both deposition and erosion processes are increased on the southern coast. About 5859 m3 of sediments are deposited in the channel gate mainly by local sources. During the northeast monsoon, both deposition and erosion processes are located over a narrow area with frequency increased on the north coast, whereas the deposition process is narrowed with higher frequency on the southern coast. The total amount of sediment deposited at the estuary is 56,446 m3, of which 74.2% is from the onsite erosion material, 15.8% from the river and 10% from the longshore transportation. Generally, due to mainly erosion-deposition processes, sediment volume is accumulated during the northeast monsoon with amount 9.6 times more than that the southwest monsoon. The erosion-deposition processes are contributed to by poor practical management and local human activities inland and in the coastal regions, as well as the natural situation, resulting in serious impacts on society, the economy and the environment. Hence, the governance of the erosion-deposition processes and sediment load in small estuaries appear to contribute to the master plan for the local sustainable development of society and the economy.