Search

Forecasting is a crucial part of supply chain management. Accurate forecasts have a strong influence on supply chain performance. Many forecasting methods have been developed and adapted in various domains and industries. However, none are perfect in all contexts due to the data's characteristics and the methods' strength. Hence, we propose a new ARIMAX‐LSTM hybrid forecasting model that integrates ARIMAX and LSTM models to improve the ability to capture different combinations of linear and nonlinear patterns in time series. Our proposed model is validated in a case study of coffee demand in Vietnam. The case study results show that our proposed model outperforms the well‐known single and current hybrid models regarding performance measures and degree of association. Moreover, to prove the model's robustness, we test and compare our proposed model to the previous study for Thailand's agricultural products (pineapple, corn, and cassava). Computational results demonstrate that our hybrid model is superior in the majority of experiments. It has a strong capability of predicting complex time series data. Furthermore, our proposed method increases forecasting accuracy and enhances supply chain performance (measured by the bullwhip effect; net‐stock amplification, and transportation cost. [ABSTRACT FROM AUTHOR]

In Industry 4.0, technology and innovation constitute a driver for enhancing firms' performance, particularly for small and medium-sized enterprises (SMEs). Our study aims to examine whether that statement is correct for SMEs in a developing country. We developed a generic model and employed multiple regression techniques, including ordinary least-squares, robust standard errors and weighted least squares, to test this hypothesis and address heteroskedasticity. Using a micro-level dataset including 11,630 SMEs in Vietnam's logistics sector, an emerging logistics market in a developing country, our results reveals that the effects of technology on firm performance may differ depending on particular metrics of this performance. Furthermore, not all forms of innovation significantly affect SME performance. Control variables such as "firm's age", "firm's size", "state ownership", "education of the manager" and "foreign activities" also play a significant role in SME performance, underscoring the importance of both internal capabilities and external technological elements. [ABSTRACT FROM AUTHOR]

Supercritical carbon dioxide (SCCO2) is a non-toxic and environmentally friendly fluid and has been used in polymerization reactions, processing, foaming, and plasticizing of polymers. Exploring the behavior and data of SCCO2 sorption and dissolution in polymers provides essential information for polymer applications. This study investigated the sorption and diffusion of SCCO2 into polyetherimide (PEI). The sorption and desorption processes of SCCO2 in PEI samples were measured in the temperature range from 40 to 60 °C, the pressure range from 20 to 40 MPa, and the sorption time from 0.25 to 52 h. This study used the ex situ gravimetric method under different operating conditions and applied the Fickian diffusion model to determine the mass diffusivity of SCCO2 during sorption and desorption processes into and out of PEI. The equilibrium mass gain fraction of SCCO2 into PEI was reported from 9.0 wt% (at 60 °C and 20 MPa) to 12.8 wt% (at 40 °C and 40 MPa). The sorption amount increased with the increasing SCCO2 pressure and decreased with the increasing SCCO2 temperature. This study showed the crossover phenomenon of equilibrium mass gain fraction isotherms with respect to SCCO2 density. Changes in the sorption mechanism in PEI were observed when the SCCO2 density was at approximately 840 kg/m3. This study qualitatively performed FTIR analysis during the SCCO2 desorption process. A CO2 antisymmetric stretching mode was observed near a wavenumber of 2340 cm−1. A comparison of loss modulus measurements of pure and SCCO2-treated PEI specimens showed the shifting of loss maxima. This result showed that the plasticization of PEI was achieved through the sorption process of SCCO2. [ABSTRACT FROM AUTHOR]

In this work, we investigate the electron mobility in SiGe/Si/SiGe quantum wells under the influence of temperature and an external magnetic field. The scattering mechanisms of remote doping and background doping are considered in the calculations of this paper. The results indicate that the temperature and magnetic field significantly affect the electronic properties of the charge carriers. [ABSTRACT FROM AUTHOR]

Background and Objectives: Drug resistant epilepsy (DRE) is a major hurdle in epilepsy, which hinders clinical care, patients' management and treatment outcomes. DRE may partially result from genetic variants that alter proteins responsible for drug targets and drug transporters in the brain. We aimed to examine the relationship between SCN1A, GABRA1 and ABCB1 polymorphism and drug response in epilepsy children in Vietnam. Materials and Methods: In total, 213 children diagnosed with epilepsy were recruited in this study (101 were drug responsive and 112 were drug resistant). Sanger sequencing had been performed in order to detect six single nucleotide polymorphisms (SNPs) belonging to SCN1A (rs2298771, rs3812718, rs10188577), GABRA1 (rs2279020) and ABCB1 (rs1128503, rs1045642) in study group. The link between SNPs and drug response status was examined by the Chi-squared test or the Fisher's exact test. Results: Among six investigated SNPs, two SNPs showed significant difference between the responsive and the resistant group. Among those, heterozygous genotype of SCN1A rs2298771 (AG) were at higher frequency in the resistant patients compared with responsive patients, playing as risk factor of refractory epilepsy. Conversely, the heterozygous genotype of SCN1A rs3812718 (CT) was significantly lower in the resistant compared with the responsive group. No significant association was found between the remaining four SNPs and drug response. Conclusions: Our study demonstrated a significant association between the SCN1A genetic polymorphism which increased risk of drug-resistant epilepsy in Vietnamese epileptic children. This important finding further supports the underlying molecular mechanisms of SCN1A genetic variants in the pathogenesis of drug-resistant epilepsy in children. [ABSTRACT FROM AUTHOR]

In the present paper, for the first time, we consider the problem of non-fragile finite-time guaranteed cost control for a class of fractional-order singular systems with norm-bounded uncertainties. Firstly, we establish a linear quadratic cost function based on the integral of integer order, which serves practical purposes and acts as a performance measure index for the closed-loop system. Then, leveraging finite-time boundedness theory, inequality techniques, and fractional-order calculus properties, we propose a non-fragile state feedback controller that ensures regularity, impulse-free, and finite-time boundedness in the closed-loop system. Furthermore, we establish an upper limit for the performance index. The resulting findings are reliant on the order of the considered fractional-order systems and are obtained through the use of strict linear matrix inequalities (LMIs), devoid of any equality restrictions. Finally, two simulation examples are provided to validate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

We investigate the problem of learning a water quality model (BOD-DO model) from given data. Assuming that all parameters in the model are constants, we reformulate the problem as a system of linear equations for the unknown terms. Since in practice the system is often under-determined or over-determined and the observed data are noisy, we use an |$l^{1}$| -weighted regularization method to find a stable approximate solution. Then, Nesterov's algorithm is used to solve the regularized problem. Learning models with variable coefficients are also discussed. Numerical examples show that our approach works well with noisy data and has the ability to learn the BOD-DO model. [ABSTRACT FROM AUTHOR]

Mango purée is a byproduct of the current production processes (such as freeze-drying, dehydration) after the product shaping stage or grades II and III mangoes. Currently, fruit bar is a convenient and highly nutritious snack made from fruit. The objective of this study is to utilize mango byproduct in order to develop a fruit bar processing technology, which is based on evaluating the quality (color, break force, vitamin C content, and sensory) when varying the pH of mango purée and the concentration of added pectin. Additionally, total soluble solids (TSS) after blending at 80°C were also investigated. The increase in pH, pectin concentration of mango purée, and TSS after blending showed that vitamin C content in fruit bars tended to decrease. TSS results revealed that at TSS = 63 °Bx, pH 3.3, and a pectin concentration of 1.3%, the product received a high rating of 6.3. Additionally, the vitamin C content of the product reached 7.82 mg/100 gDW. The results of this study are expected on the diversification of products from mango. Solving the situation that grades II and III mangoes are difficult to be commercialized and making the most of the byproduct mango flesh after certain production processes. [ABSTRACT FROM AUTHOR]

The article presents the facies and environment of the Upper Oligocene sediments in the area of block 09-2/10 based on the analysis of seismic facies and well data of the neighboring areas. The results of the interpretation of seismic data indicate that the upper Oligocene sediments are limited by the top C, top D seismic reflectors. The environment is formed from lagoons, lakes to deep lakes. Seismological facies analysis identified 03 facies including seismic facies with medium to poor reflection amplitude, medium continuous, low frequency reflecting the lacustrine sediments (80%) in most of the lake center. Strong reflective seismic facies, sigmoidal clinoforms reflect the lakeside sediments (15%) distributed in the lakeside shelf. The seismic facies with average and continuous amplitude poorly reflect alluvial sediments (5%) in the Northwest region. The direction of sediment transport is mainly from the Northwest and Southwest in the area. The sandstone sequences are distributed on the slopes of the lake and the lake bottom, which is potential reservoir. [ABSTRACT FROM AUTHOR]

Song Hong basin is a very large basin with complicated onshore to offshore geological structure. The basin comprises the pre-Tertiary basement and Kainozoi sequences. This study focused on the evolution of submarine channel in Miocene sequence. The study interval is the major reservoir of the basin characterized as submarine channel complex and lower to Middle Miocene carbonates with the porosity of 15–25%. The channel is highly eroded into the substrate with c. 7 km wide and 20 km long, trending northwest-southeast. They are ‘U’ to ‘V’ shape, sub-parallel to deep faults which reactivated in the Early and Mid-Late Miocene. The channel deposit is characterized by cut and fill architecture and can be seen as high amplitude, bi-directional downlap. The channels are likely to be controlled by the two inverted phases in Late Oligocene and Middle-Late Miocene. The tectonic events are not only controls the flow directions but also modified the shape of the channels. The occurrence of well-developed submarine channel give a great hydrocarbon potential for the Song Hong basin. [ABSTRACT FROM AUTHOR]

Freezing is considered an effective means to preserve fruits without using any chemical preservatives. In this study, the effects of ripeness levels and two freezing temperatures (-25°C and -86°C) on the frozen pineapples were evaluated. The faster freezing rate (0.4 °C/min) was obtained by the -86°C freezing system to achieve the core temperature of -18°C in frozen pineapple in ~0.65 h compared to that at -25°C with respective to freezing rate of 0.09 °C/min and freezing time of ~3 h. Freezing pineapple fruits at -86°C was found to reduce the drip loss, vitamin C, and structure loss compared to that at -25°C. Ripeness levels were found to cause significant impacts on the quality of frozen pineapples. The increase in ripeness level (level 1 to level 4) was found to cause the increment in freezing time, drip loss, and vitamin C loss. Meanwhile, frozen pineapple fruits the green maturity (ripeness level 1) were observed with lower structure retention compared to riper pineapple (level 2 to level 4). The total soluble solids (TSS) and titratable acidity of frozen pineapples were found to be insignificantly affected by the freezing temperatures and ripeness levels. The freezing system at -86°C for frozen pineapple was found to promote better performance in maintaining the quality of frozen pineapple products. [ABSTRACT FROM AUTHOR]

In this paper, we study a proximal method for the minimization problem arising from l0-regularization for nonlinear inverse problems. First of all, we prove the existence of solutions and give an optimality condition for solutions to the minimization problem. Then, we propose and prove the convergence of the proximal method for this minimization problem, which is controlled by step size conditions. Finally, we illustrate performance of the proximal method by applying it to a numerical example. [ABSTRACT FROM AUTHOR]

Demand planning enables organizations to manage their and their partner supply chain processes. We introduce and evaluate the demand planning process, including the aspects of goal formulation, forecasting techniques, information source, forecasting and decision making, and synchronizing supply with demand. We, especially, show its applicability and evaluation in a Vietnamese coffee supply chain context, which also provides insights for general supply chain and organizational practices, especially in emerging economies. We find that the demand planning relates strongly to cost and delivery performance. There is greater evidence that demand planning is not only valuable but has multiple important dimensions that managers and organizations need to be concerned within its implementation. We provide some practical insights into the design of demand planning as well as issues that organizations may face. [ABSTRACT FROM AUTHOR]

The sacha inchi seeds (Plukenetia Volubilis L.), collected from different ecological regions of Vietnam (the Northern Mountainous region, the North Central region, and Central Highlands Area), were sown in the spring crop (March 2020) in Gia Lam district, Hanoi city, Vietnam. The variety S18 was copyrighted by Ministry of Agriculture and Rural Developmentof Vietnam in 2019 as a special medicinal plant variety. During the period of 26 months after planting, the agronomical parameters, growth and development characteristics (leaf form, number of inflorescences per branches, number of female flowers per inflorescences, etc.), pests and diseases, yields and yield components (number of seeds per fruit, seed weight, seed grain, etc.), ratio of kernel per seed and ratio of oil per seed were evaluated. The evaluation results show that the collected sacha inchi lines have a time from sowing to flowering and fruiting of 108-125 days, a fruiting to ripening of 123-125 days, and a time from sowing to harvesting the first batch of 244-250 days. The annual harvest is carried out at two main times: May-June and November-January. The actual yield of the first two periods is high (2.66-3.07 tons per hectare), and the highest yield is collected in the Northern Mountainous area is 3.07 tons per hectare (in Tuyen Quang province), while and 3.01 tons per hectare are collected in the North Central region (in Thanh Hoa province). In the nursery, root rot caused 2.1-5.3% deaths and green wilt caused 3.1-4.8% deaths of seedlings. In the planting garden, fruit borers, stem borers, cavity worms and red spiders were discovered, causing more serious damage than other types (from 5 to over 50%). The results of evaluation of growth, development, yield components and yield showed that the sacha inchi lines collected in the North Central region (in Thanh Hoa province) and the Northern Mountainous region (in Tuyen Quang province) is the best. [ABSTRACT FROM AUTHOR]

In this work, using the compact density matrix approach, we study the linear and nonlinear magneto-optical properties of monolayer molybdenum disulfide (MoS2) via an investigation of the absorption coefficients (MOACs) and refractive index changes (RICs). The results are presented as functions of photon energy and external magnetic field. Our results show that the MOACs and the RICs appear as a series of peaks in the inter-band transitions between Landau levels, while the intra-band transitions result in only one peak. Because of the strong spin-orbit coupling, the peaks caused by the spin-up and -down states are different. With the increase in the magnetic field, both MOACs and RICs give a blue-shift and reduce in their amplitudes. These results suggest a potential application of monolayer MoS2 in the optoelectronic technology, magneto-optical, valleytronic, and spintronic devices. [ABSTRACT FROM AUTHOR]

Two new compounds, comprising one dibenzofuran, named usneaceratin A (1), and one phenolic acid, named usneaceratin B (2), together with one known dibenzofuran, isousnic acid (3), and two known phenolics, orsellinic acid (4) and methyl orsellinate (5) were clarified from the lichen Usnea ceratina using variously chromatographic methods. Their structures were testified by comprehensive HR-ESI-MS, and NMR spectroscopic analysis, and comparison with published data. Their α-glucosidase inhibitory activity of all compounds was measured. Usneaceratin B (2) possessed better inhibition against α-glucosidase enzyme (IC50 value of 41.8 μM) than the standard drug acarbose (IC50 value of 214.50 μM). [ABSTRACT FROM AUTHOR]

Chemical investigation of the lichen Parmotrema tinctorum (Nyl.) Hale led to the isolation of two new phenolic compounds, 2-ethylhexyl orsellinate (1) and tinctorinone (2). The structures were determined by analysis of their MS and NMR data as well as by comparison with literature data. The 2-ethylhexyl ester group of 2-ethylhexyl orsellinate is uncommon among lichen metabolites. Tinctorinone revealed strong inhibition towards α-glucosidase. [ABSTRACT FROM AUTHOR]

Chemical investigation of the lichen Usnea ceratina Arch led to the isolation of five depsidones, including one new compound ceratinalone (1) along with four known compounds bailesidone (2), stictic acid (3), 8′-O-methylstictic acid (4) and 8′-O-ethylstictic acid (5). The structures were determined by analysis of their MS and NMR data as well as by comparison with literature values. Compounds 1 and 4 were evaluated the cytotoxic activity against HeLa (human epithelial carcinoma), NCI-H460 (human lung cancer), HepG2 (liver hepatocellular carcinoma), and MCF-7 (human breast cancer) cell lines, showing the moderate activity. [ABSTRACT FROM AUTHOR]

Three new diphenyl ethers, named praesorethers E, F and G (1, 2 and 3), were isolated from the lichen Parmotrema praesorediosum. Their chemical structures were elucidated on the basis of extensively spectroscopic analysis including HR-ESI-MS and NMR as well as comparison with previously published data. These compounds were evaluated for the cytotoxicity against three human cancer cell lines (HeLa, NCI-H460 and MCF-7) using SRB assay. As results, 1 and 2 exhibited weak cytotoxic activity against three tested cancer cell lines with the inhibitive percentage of 64–79.9% at the concentration of 100 μg/mL while 3 was inactive. [ABSTRACT FROM AUTHOR]

Let S be a right reversible semitopological semigroup, and let LUC (S) be the space of left uniformly continuous functions on S. Suppose that LUC (S) has a left invariant mean. Let K be a weakly compact convex subset of a Banach space not necessarily with normal structure. We show that there always exists a common fixed point for any jointly weakly continuous and super asymptotically nonexpansive action of S on K. Several variances involving the weak* compactness, the RNP, the distality of K and/or the left reversibility of S are also provided. [ABSTRACT FROM AUTHOR]

Vegetables have been shown to be able to provide nutrients, including vitamins, minerals and especially fiber, and release toxins that arise during the digestion of food. As a result, the importance of vegetables has been increasingly emphasized in the human diet. In this study, Kohlrabi, a vitamin C-rich vegetable, was used for lactic fermentation. The whole process was optimized by varying a wide range of parameters including concentrations of salt solution and pH value on the growth of lactic acid bacteria, product texture and sensory characteristics. Current results revealed the optimal conditions for the fermentation process are as follows: NaCl solution used of 3.5%, initial pH 4.2, and MnCl2 with a concentration of 30 mM. The obtained Kohlrabi pickle products exhibited acceptable quality and good sensory scores after 2 days. Elevated temperature was also found to be associated with loss of hardness, quality loss and longer fermentation time. Optimized Kohlrabi pickling process will contribute to diversifying pickled vegetable products to avoid the defects caused by improper processing. [ABSTRACT FROM AUTHOR]

We consider a multiscale elliptic eigenvalue problem that depends on n separable microscopic scales. Using multiscale homogenization, we derive the multiscale homogenized eigenvalue problem whose solution contains all the possible eigenvalues and eigenfunctions of the homogenized eigenvalue problem. We develop the sparse tensor product finite element (FE) method for solving this multiscale homogenized problem, thus bypassing the expensive task of forming the homogenized equation. Although the multiscale homogenized eigenvalue problem is posed in a high dimensional tensorized domain, the sparse tensor product FEs achieve a prescribed level of accuracy requiring an essentially optimal number of degrees of freedom which differs from the optimal one by only a possible logarithmic multiplying factor, given that the solution to this problem is sufficiently regular. We show that the regularity requirement is achieved under the Lipschitz condition on the multiscale coefficient. Numerical examples on two- and three-scale eigenvalue problems support the theoretical error estimates. [ABSTRACT FROM AUTHOR]

The goal of this research is to evaluate the influence of the polyphenols extract of Polygonum multiflorum Thunb. root on the lipid oxidation, chemical properties and sensory characteristics of ground beef during frozen storage. Beef was ground in aqueous solutions of polyphenols extract at different concentrations: 830, 415, 277, 208 and 166 mg GAE/L, polyphenols solution/sample ratio is 1/20 (v/w). Then, the ground beef was stored for up to 100 days at -20±2oC. The best oxidation inhibitor for ground beef was at the highest polyphenols concentration of 830 mg GAE/L. All quality parameters (pH, PoV, MDA, color parameter and sensory evaluation) of the treated sample and of the control sample display significant differences (p<0.05) during storage period. For this reason, it was concluded that the polyphenols extract of Polygonum multiflorum Thunb. root could be used as an alternative source of natural antioxidant in beef processing. [ABSTRACT FROM AUTHOR]

The paper empirically analyzes the role of tax policy in FDI-Environmental pollution nexus in developing countries from 2004 to 2016. In general, FDI has a significant effect to increase air pollution in these countries supporting the pollution haven hypothesis. Interestingly, the government plays a crucial role to adjust the environmental impacts of FDI. When the higher quality of institution helps to reduce air pollution, the tax policy has both the direct effect to reduce the level of environmental degradation and the indirect effect through mitigating the harmful environmental impact of FDI in this case. [ABSTRACT FROM AUTHOR]

In this paper, we propose an linear matrix inequality (LMI)-based design method to observer-based control problem of linear descriptor systems with multiple time-varying delays. The delay function can be continuous and bounded but not necessarily differentiable. First, by introducing a new set of improved Lyapunov–Krasovskii functionals that avoid calculating the derivative of the delay function, we obtain new delay-dependent sufficient conditions for guaranteeing the system to be regular, impulse-free and asymptotically stable. Then, based on the derived stability conditions, we design state feedback controllers and observer gains via LMIs, which can be solved numerically in standard computational algorithms. A numerical example with simulation is given to demonstrate the efficiency and validity of the proposed deign. [ABSTRACT FROM AUTHOR]

We consider a general ill-posed inverse problem in a Hilbert space setting by minimizing a misfit functional coupling with a multi-penalty regularization for stabilization. For solving this minimization problem, we investigate two proximal algorithms with stepsize controls: a proximal fixed point algorithm and an alternating proximal algorithm. We prove the decrease of the objective functional and the convergence of both update schemes to a stationary point under mild conditions on the stepsizes. These algorithms are then applied to the sparse and non-negative matrix factorization problems. Based on a priori information of non-negativity and sparsity of the exact solution, the problem is regularized by corresponding terms. In both cases, the implementation of our proposed algorithms is straight-forward since the evaluation of the proximal operators in these problems can be done explicitly. Finally, we test the proposed algorithms for the non-negative sparse matrix factorization problem with both simulated and real-world data and discuss reconstruction performance, convergence, as well as achieved sparsity. [ABSTRACT FROM AUTHOR]

In this work, we study systematically low-energy bands, optical absorbance and spin/valley-Hall conductivity of silicene and germanene in the presence of a perpendicular electric field. Our analytical calculations indicate that both silicene and germanene are semiconductors with a tiny energy gap and we can control their energy gap by the perpendicular electric field. Our calculations also demonstrate that the low-frequency optical absorbance of silicene is much greater than that of germanene and the external electric field plays an important role in determining the optical absorption peaks. When the Fermi level is in the forbidden band, the Hall conductivity is quantized, while spin/valley-Hall conductivities of both silicene and germanene depend strongly on the Fermi energy when the Fermi level is in the conduction band. Analytical results for spin/valley-Hall conductivities of silicene and germanene are presented in detail in this work. [ABSTRACT FROM AUTHOR]

The utilization of three important freshwater fish skins including tra catfish (Pangasianodon hypophthalmus), clown knifefish (Chitala ornata), and tilapia (Oreochromis niloticus) in Mekong Delta Region, Vietnam for acid‐soluble collagen (ASC) extraction was investigated. From the SDS‐PAGE profile, ASCs can be identified as type I collagen (consisting of two different α‐ chains and β component in protein pattern).The solubility among individual collagens was highest at pH 1–2, depending on fish species. FTIR spectra showed a close relationship between the lowest wavelength number in amide I and amide III regions and the stabilization of the triple‐helical structure in ASC from clown knifefish. ASC from clown knifefish skin had highest ASC yield and contained highest amino acid content as well as the highest denaturation temperature (33.09°C) in comparison with ASCs from tra catfish and tilapia skin. Practical applications: Acid‐soluble collagen (ASC) from three important fish skins in the Mekong Delta Region, Vietnam was characterized. ASC from clown knifefish skin showed the highest of extraction yield and denaturation temperature. The thermal stability of ASC from clown knifefish skin not only related to the content of imino acid but is also had the correlation with the transition of α‐helix in amide I and III. [ABSTRACT FROM AUTHOR]

In the current market economy, it is important to evaluate and forecast the situation and business performance of enterprises to provide the necessary information for managers to plan for future use of resources. This study aims to evaluate and predict the business performance of logistics companies in Vietnam. The authors use the optimal algorithm in the data envelopment analysis (DEA) to evaluate the business efficiency of the companies in the years 2014–2017. In addition, the authors use Grey system theory to forecast business results and their future use during the period of 2018–2021. The research shows that Gemadept Corporation and Sea & Air Freight International use the their business resources effectively and as expected, and that these companies will continue to thrive in the future. This study provides a method to measure, evaluate, and forecast the business performance of the logistics companies. Managers and the government can rely on this approach for implementation and overall planning of logistics enterprises in the future. [ABSTRACT FROM AUTHOR]

The rapid expansion of supercritical solution (RESS) technology was applied to recrystallize and micronize three active pharmaceutical ingredients (APIs) of monobenzone, ethylparaben, and kojic acid. All unprocessed (original) APIs had a large mean particle size over 200 μm with wide particle size distribution. Supercritical carbon dioxide served as the solvent to extract each API in a high‐pressure vessel. The nearly saturated supercritical solution was then expanded through a capillary spray nozzle to ambient pressure state. The APIs were recrystallized in a very short time period. The final API particles with submicron sizes were obtained with much less intensity of crystallinity. The optimal RESS process parameters and the improved result of the in vitro dissolution test for the API of ethylparaben are reported. [ABSTRACT FROM AUTHOR]

We report a dual genotype Orientia tsutsugamushi infection in Vietnam in 2016. The patient had fever, rash, and an eschar. The Kawasaki genotype was identified in the eschar specimen and Karp genotype in the whole blood specimen. The genotype co-infection rate for scrub typhus is unknown and should be further evaluated. [ABSTRACT FROM AUTHOR]

The lacustrine oil-prone organic-rich mudstones in the Oligocene are the most important source rocks which have contributed to generate significant hydrocarbon accumulations in the northern Song Hong basin but still poor understanding due to the limitation of data. Newly c. 800km2 3D seismic data and well data allows investigating the stratigraphy and geochemistry of the northern Song Hong basin in detail to define the stratigraphic framework and hydrocarbon potential. The area is characterized by three relatively elongate grabens which are separated by the northeast-southwest basement faults. The most completed synrift sequence is observed in the central graben and is divided into three distinct sections, lower section (O1), middle (Om) and upper (Ou), corresponding to three phases defined by tectonic systems tracts, from rift initiation to rift development and finally fill up phase. Uplift at the end of Oligocene has strongly modified the syn-rift sequences, resulting in folding, reactivated some basement faults and generated a series of new EW trending faults which may act as potential structural traps in the area. Organic geochemical analysis of the lacustrine mudstone samples from O1 and Om section of well D-1X shows fair to high organic carbon contents, Total Organic Carbon (TOC) 0.51 - 4.86 wt% and Hydrogen Index (HI) 273 - 552 mg HC/g TOC, corresponding to the type II kerogen. Biomarkers indicate the contribution of algal, high land plant, and bacterial sources to the composition of organic matters. Organic matters were deposited in the less oxic environment, in the fresh-water to brackish marine influence. [ABSTRACT FROM AUTHOR]

Hypertension and atherosclerotic diseases are becoming important public health issues in Vietnam. This is due, in part, to changing dietary patterns and lifestyles accompanying economic growth in the country. The most recent prevalence data suggest that 29% of the population has hypertension, and the rate of other cardiovascular risk factors is also high. Although use of home and ambulatory blood pressure monitoring (HBPM and ABPM) is increasing, Vietnamese physicians generally rely on office blood pressure (BP) for diagnosing and managing hypertension. A lack of availability and training are limiting factors. However, out-of-office BP monitoring is important to detect white-coat and masked hypertension, and define the 24-hour BP profile. This approach is recommended in current Vietnam Society of Hypertension and Vietnamese National Heart Association guidelines. Based on 2016 data, the most commonly used antihypertensive agents in Vietnam are angiotensin-converting enzyme (ACE) inhibitors, followed by calcium channel blockers (CCBs) and diuretics, with ß-blockers and angiotensin receptor blockers used less frequently. Combination therapy, usually with an ACE inhibitor plus CCB or diuretic, is quite common (used in 62% of patients). The participation of Vietnam in global hypertension initiatives and organizations has likely contributed to improved treatment and control rates over the last 10 years. Nevertheless, the prevalence of hypertension remains high and additional strategies are needed to reduce this and prevent cardiovascular disease. [ABSTRACT FROM AUTHOR]

The purpose of this research is to investigate the presence of alkaloids, saponins, flavonoids, anthraquinones and tannins compounds as the possible agent responsible for the medicinal activities, the antioxidant activities and antimicrobial activities from Polygonum multiflorum Thunb. root. The powdered root was analyzed positively for alkaloids, saponins, flavonoids, anthraquinones and tannins. In addition, they are also related to an antimicrobial activity and the presence of these constituents was helpful to apply in medical and food industry. The determination of antimicrobial activity of Polygonum multiflorum Thunb. root extracts against gramnegative Escherichia coli (ATCC 25922), Salmonella enteritidis (ATCC 13076), gram-positive: Staphylococcus aureus (ATCC 25923), Bacillus subtilis (ATCC 11774), Listeria monocytogenes (CIP 74908), fungi: Fusarium equiseti, Aspergillus niger and Trichoderma asperellum were investigated by the paper disc diffusion method for antibiotic susceptibility testing and minimum inhibitory concentration (MIC) evaluation of dryness extract. The results showed that the dryness extract can inhibit one grampositive bacteria (Staphylococcus aureus, MIC = 200 mg/mL), one gramnegative bacteria (Salmonella enteritidis, MIC = 400 mg/mL) and one fungus (Trichoderma asperellum, MIC = 100 mg/mL); it's not take effectively on Escherichia coli, Bacillus subtilis, Listeria monocytogenes, Fusarium equiseti and Aspergillus niger. [ABSTRACT FROM AUTHOR]

The goal of this study is to examine the influence of type of solvent (acetone, ethanol, methanol, and water), raw solvent/ material ratio (20/1-60/1, v/w), solvent concentration (30-80%, v/v), temperature (30-70°C), time of extraction (10-30 mins) and power consumption of 550 W on the extraction yield of total phenolic compounds (TPC) and antioxidant activity (AC) from Polygonum multiflorum Thunb. roots. TPC and AC were determined by the Folin-Ciocalteu assay and DPPH assay. The optimal conditions for extraction process were 60% acetone-water mixture as solvent, solvent/material ratio of 30/1, extraction temperature of 60°C and extraction time of 15 mins. TPC and AC obtained were approximate 43.28±0.54 mg GAE/g DW (Dry weight) and 343.88±3.06 μmol TE/g DW, respectively. The effect of ultrasound-assisted extraction (UAE) on structure of materials of Polygonum multiflorum Thunb. root was observed by scanning electron microscopy (SEM). HPLC method was employed to determinate some main phenolic compounds including catechin, gallic acid, and resveratrol. [ABSTRACT FROM AUTHOR]

The main purpose of this research was to investigate the accelerated shelf-life of phenolic compounds in Polygonum multiflorum (Thunb.) root extract and its spray dried products at various temperatures. Using the Q10 model helped in observing the degradation of the total polyphenol content (TPC) and antioxidant capacity (AC) of the product, while enabling an accurate prediction of the its shelf-life at different storage temperatures. The results showed that the degradation of TPC and AC of the extract was rapid at elevated temperatures. The spray-dried products maintained TPC and AC better than the extract. TPC and AC retention of 85% of the extract were approximately 42.4 and 5.1 days at 30oC, respectively. While TPC and AC retention of 85% of gum arabic were 6.2 and 13.1 days, TPC and AC retention of 85% of maltodextrin (DE 16-19) were 14.68 and 7.16 days, respectively. The obtained model was reliable and easy to use. [ABSTRACT FROM AUTHOR]

Finite‐time stabilisation involves finding state feedback controllers which stabilise the closed‐loop system in a finite‐time interval. This paper deals with robust finite‐time stabilisation of linear singular systems with interval time‐varying delay. Based on singular value decomposition method and a generalised Jensen inequality, we provide sufficient conditions for the design of such controllers guaranteeing the finite‐time stability of the closed‐loop system. The proposed conditions are expressed in terms of linear matrix inequalities. Numerical examples are given to illustrate the effectiveness of the proposed methods. [ABSTRACT FROM AUTHOR]

The objective of this study was to figure out the optimal conditions for polyphenol extraction from Polygonum multiflorum Thunb. roots using pectinaseassisted extraction method. In this research, total phenolic contents (TPC) were determined by the Folin Ciocalteu method and antioxidant capacity (AC) was analyzed by free radical scavenging activity method with Trolox and DPPH as standard reagents. They were described by gallic acid equivalent (GAE) and Trolox equivalent (TE), respectively. The factors from extraction process were studied, gave the highest total phenolic content and strongest antioxidant capacity including material/solvent ratio (1/5 - 1/13), enzyme concentration (0.1% - 0.5%), extraction time (40 - 120 minutes), pH (3.5 - 5.5) and extraction temperature of (30°C-70°C). The optimal extraction conditions achieved such as the material/solvent of 1/11, enzyme concentration of 0.2%, extraction temperature of 50°C, pH value of 4.5 and extraction time of 80 minutes. TPC and AC peaked at 44.36 mg GAE/g DW (dry weight) and 80.43 µmol TE/g DW. After treatment, the materials were changed strongly and were also observed by scanning electron microscopy (SEM). Some extractive compounds of phenolic such as gallic acid and catechin were determined by HPLC method. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the adaptation and possible ex situ conservation in a subtropical region of the Partridge coloured Hungarian (PH), a native Hungarian chicken breed, by monitoring and comparing the performance of two PH flocks reared in parallel in Hungary (HU) and Vietnam (VN). The high survival rate (95.0-96.5%), overall productivity and reproductive ability of the VN flock confirmed the adaptation potential of PH chickens to subtropical climates. A relatively good bodyweight (1412 ± 13.8 g) and slaughter yield (75.6 ± 0.02% eviscerated carcass and 28.2 ± 0.12% deboned thigh meat) in male VN birds at 12 weeks of age was obtained. Moreover, it was found that benefits such as the number of eggs (112 eggs/layer in 7 months) and egg mass (6.1 kg/layer) alongside considerably higher fertility (85.9 ± 2.9%) and hatchability (82.0 ± 3.2%) of VN layers could outweigh their reduced egg size. As a result, the study confirms that the adaptation and maintenance of populations in subtropical regions is a promising agro-ecological way to protect native Hungarian chicken breeds and improve their involvement in production. [ABSTRACT FROM AUTHOR]

It is proved that the iterative sequence constructed by the Basic Trust-Region Algorithm (see Conn et al. in Trust-region methods, MPS-SIAM series on optimization, Philadelphia, 2000), which uses the Cauchy point method, is locally stable and linearly convergent in a neighborhood of a nonsingular local minimizer. [ABSTRACT FROM AUTHOR]

This paper deals with finite-time stability and stabilization problem of singular linear discrete-time systems with time-varying delay and norm-bounded disturbance. We first present novel delay-dependent sufficient conditions for the robust finite-time stability of the system. Then the results are applied to solve finite-time stabilization problem of linear singular discrete-time control delay systems. The conditions are presented in terms of linear matrix inequalities, which can be determined by utilizing MATLABs LMI Control Toolbox. The effectiveness of the results are illustrated by numerical examples. [ABSTRACT FROM AUTHOR]

In this paper, we investigate sparsity regularization for the diffusion coefficient identification problem. Here, the regularization method is incorporated with the energy functional approach. The advantages of our approach are to deal with convex minimization problems. Therefore, the well-posedness of the problem is obtained without requiring regularity property of the parameter. The convexity of regularized problems also allows use the fast algorithms developed recently. Furthermore, the convergence rates of the method are obtained under a simple source condition. The main results of this paper are the well-posedness and convergence rates of sparsity regularization. We also obtain some new results of the continuity and the differentiability of related operators. [ABSTRACT FROM AUTHOR]

In this paper, we investigate an inverse problem in electrical impedance tomography. Based on measured data and the sparsity of conductivity coefficients, we use sparse regularization with a suitable fitting functional that replaces the least square functional as often used. Our main results are the differentiability of the new functional, the well-posedness and convergence rates of the regularization method as well as a discussion on Sobolev gradient. Finally, numerical solutions are analyzed and compared for different measured data-sets. [ABSTRACT FROM AUTHOR]

Stanford type A aortic dissections often present to the hospital requiring emergent surgical intervention. Initial diagnosis is usually made by computed tomography; however transesophageal echocardiography (TEE) can further characterize aortic dissections with specific advantages: It may be performed on an unstable patient, it can be used intra-operatively, and it has the ability to provide continuous real-time information. Three-dimensional (3D) TEE has become more accessible over recent years allowing it to serve as an additional tool in the operating room. We present a case series of three patients presenting with type A aortic dissections and the advantages of intra-operative 3D TEE to diagnose the extent of dissection in each case. Prior case reports have demonstrated the use of 3D TEE in type A aortic dissections to characterize the extent of dissection and involvement of neighboring structures. In our three cases described, 3D TEE provided additional understanding of spatial relationships between the dissection flap and neighboring structures such as the aortic valve and coronary orifices that were not fully appreciated with two-dimensional TEE, which affected surgical decisions in the operating room. This case series demonstrates the utility and benefit of real-time 3D TEE during intra-operative management of a type A aortic dissection. [ABSTRACT FROM AUTHOR]

The study shows the changes of total polyphenol compounds and antioxidant activities of Polygonum multiflorum Thunb root extract during the preservation time by freezing method. In addition, the treatment of initially raw materials by drying process also affects strongly total polyphenol compounds and antioxidant activity. Total phenolic compounds were determined by the Folin Ciocalteu method and antioxidant activity was analyzed by radical scavenging activity on 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical. The results point out that Polygonum multiflorum Thunb (fresh samples) can be preserved for 3 months at -20°C but content of polyphenol and antioxidant activity decrease significantly by 60%. Fresh samples were dried at 60°C for 4 hours and methods including magnetic stirrer extraction (MSE), microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE), and enzyme (α-amylase SC) assisted extraction (EAE) with deionized water as solvent, were used to extract polyphenol in this research. MAE has the shortest treatment time (6 minutes) and the best results (highest total polyphenol) as 44.37 mg GAE/g DW and antioxidant activity value was 132.73 μmol Trolox/g DW. Conversely, EAE and MSE methods give the worst yield (22.81 mg GAE/g DW, 24.51 mg GAE/g DW and 136 μmol Trolox/g DW, 175.29 μmol Trolox/g DW respectively) and require the longest extraction time (from 1 to 2 hours). [ABSTRACT FROM AUTHOR]