This study aimed to investigate the effect of a surfactant on the liquid-liquid phase separation, dissolution, diffusion, and the oral bioavailability of a weakly basic drug (l-tetrahydropalmatine; ...l-THP) from an amorphous solid dispersion (ASD). The carrier used in the ASD was optimized by the application of casting film, solvent shift, and pH shift methods. The interaction between the optimized carrier (HPMCP) and l-THP was then evaluated by Fourier transform-infrared spectroscopy and powder X-ray diffraction. The impact of the surfactant on ASD prepared by the spray-drying method was evaluated by both in vitro and in vivo studies. The results of in vitro studies, including liquid-liquid phase separation, drug diffusion, and pH-shift dissolution, indicated that the addition of a surfactant at a certain concentration below critical micelle concentration to ASD caused the precipitation of and a reduction in the membrane diffusion of l-THP in pH 6.8. This observation was confirmed in an in vivo study in which the drug concentration of l-THP in rabbit plasma was determined by the LC-MS/MS analysis method. Then the absolute and relative bioavailability of l-THP was calculated from the obtained pharmacokinetic parameters. Specifically, the addition of 1.5% surfactant (Poloxamer 188) to the binary ASD decreased the relative bioavailability of l-THP by approximately 2.4 times compared with the original binary ASD. Besides, the study proved that l-THP had low absolute bioavailability (around 1.24%), and the application of binary ASD was meaningful in enhancing the oral bioavailability of l-THP by around 334.77% compared to the raw material. The study is expected to provide a better understanding of how different dosage forms influence the bioavailability of l-THP, thereby allowing the selection of the optimal approach for this weakly basic drug.
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This is the first time in Vietnam that people have undergone “social distancing” to minimize the spreading of infectious disease, COVID-19. These deliberate preemptive strategies may have profound ...impacts on the mental health of the population. Therefore, this study aimed to identify the psychological impacts of COVID-19 on Vietnamese people and associated factors. We conducted a cross-sectional study during a one-week social distancing and isolation from April 7 to 14, 2020, in Vietnam. A snowball sampling technique was carried out to recruit participants. Impact of Event Scale-Revised (IES-R) was utilized to assess the psychological impacts of the COVID-19. Of all participants, 233 (16.4%) reported low level of PTSS; 76 (5.3%) rated as moderate, and 77 (5.4%) reported extreme psychological conditions. Being female, above 44 years old, or having a higher number of children in the family were positively associated with a higher level of psychological distress. Being self-employed/unemployed/retired was associated with a higher score of intrusion and hyperarousal subscale. Individuals who have a history of touching objects with the possibility of spreading coronavirus (utensils) were related to a higher level of avoidance. There were relatively high rates of participants suffering from PTSS during the first national lockdown related to COVID-19. Comprehensive strategies for the screen of psychological problems and to support high-risk groups are critical, especially females, middle-aged adults and the elderly, affected laborers, and health care professionals.
In this study, the generation of hydrogen from synthesis gas through the pyrolysis of modified Water Hyacinth (Eichhornia Crassipes) biomass was investigated. The modified Water Hyacinth feedstocks ...were prepared by immersing its dried samples into Iron Chlorides (III) solution under different concentrations (0.5, 1, 1.5, and 2 M). After a 60 min pyrolysis at 540 °C, each created biochar sample also generates a different volume of synthesis gas depending on the properties of the feedstock that were applied to the system. In that manner, it is clear that the value of ferric chloride concentration plays an important role in the generating of synthesis gas. The study indicates that the increase of ferric chloride concentration may also raise the production of synthesis gas, and the amount of hydrogen as well. The result indicates that the 2WH sample (with 2 M of ferric chloride catalyst) exhibited the highest conversion for Water Hyacinth pyrolysis volatiles, with 280 mL of total gas production (42% of hydrogen included, 23% of carbon dioxide, 22% of carbon monoxide and 7% of methane). Therefore, the main objective of the work is achieved by revealing the influence of the metal catalyst over the production of gases via the pyrolysis. On the other hand, the fact that the Water Hyacinth can be utilized effectively also contributes greatly to the matter of environmental betterment.
•Producing notable amount of hydrogen.•Cheap eco-friendly Water Hyacinth biochar obtained.•Cost effective system to produce hydrogen gas.•Clarify the role of metal catalyst in pyrolysis process.
This article aims to provide the intellectual structure and the evolution of research themes in social entrepreneurship. The authors deploy co-citation and co-word analyses to scrutinise 1278 social ...entrepreneurship research from the Web of Science database. In the co-citation analysis, five themes in social entrepreneurship are identified. These include the concept development of social entrepreneurship and social enterprise; bricolage and issues related to management in social entrepreneurship; opportunity recognition, motivation and intention; social innovation in social entrepreneurship; and institutional contexts. After that, the co-word analysis is used to comprehend the evolution of each research theme and to uncover potential future research directions. This research contributes to social entrepreneurship literature by combining co-citation analysis and keyword analysis to determine the literature structure and potential research directions.
The relationship between age and seroprevalence can be used to estimate the annual attack rate of an infectious disease. For pathogens with multiple serologically distinct strains, there is a need to ...describe composite exposure to an antigenically variable group of pathogens. In this study, we assay 24,402 general-population serum samples, collected in Vietnam between 2009 to 2015, for antibodies to eleven human influenza A strains. We report that a principal components decomposition of antibody titer data gives the first principal component as an appropriate surrogate for seroprevalence; this results in annual attack rate estimates of 25.6% (95% CI: 24.1% - 27.1%) for subtype H3 and 16.0% (95% CI: 14.7% - 17.3%) for subtype H1. The remaining principal components separate the strains by serological similarity and associate birth cohorts with their particular influenza histories. Our work shows that dimensionality reduction can be used on human antibody profiles to construct an age-seroprevalence relationship for antigenically variable pathogens.
This paper presents data transmission over a 26 GHz millimeter-wave (mmW) radio signal and its coverage extension in an indoor environment using the radio-over-fiber (RoF) technology. The proposed ...system consists of two RoF seamless wireless links to emulate a mobile fronthaul using a transparent RoF relay link to overcome higher attenuation of the mmW signal. The system is experimentally evaluated for up to 64-quadrature amplitude modulation (QAM), showing the possibility of signal transmission over up to 20 km of optical fiber in the first section transmission scheme without the usage of an optical amplifier. For the system with 20 km and 30 m long RoF links as well as 4 m and 1 m long relays with no optical amplification, the minimal experimentally measured error vector magnitude is as low as 5 % for 64-QAM. Further, a self-developed integrable optoelectronic extender is used for the relay RoF system to simplify the antenna site and keep its footprint small. Moreover, the proposed setup is extended using an optical amplifier toward a scalable scheme with up to 75 km of optical fiber and 5 m long free space optical link.
Sarcopenia, a condition characterized by muscle mass decline, is one of the leading health problems in the elderly. This study determined the rate of sarcopenia according to criteria by Asian Working ...Group for Sarcopenia (AWGS) and related factors in elderly people. A community-based cross-sectional study was conducted in 632 people aged 60 years or over in Ho Chi Minh City. Data were collected through a predefined questionnaire and direct measurement. Sarcopenia was identified based on the Inbody 770 machine and AWGS criteria. The prevalence of sarcopenia was 32.0%. Participants with advanced age, low education, unemployment, low level of family economics and frailty were more likely to have sarcopenia. Among these, frailty had the highest impact on sarcopenia, with significantly higher odds of having sarcopenia found in participants with pre-frailty (OR = 4.80, 95% CI 2.75-8.38, p < 0.001) and frailty (OR = 21.16, 95% CI 8.96-49.97, p < 0.001). In contrast, BMI was inversely associated with sarcopenia. Sarcopenia is prevalent in the Vietnamese elderly. Apart from social demographic characteristics including age, education, employment and family economic status, frailty appeared to be an important risk factor. Early screening, referral, and treatment of sarcopenia among the elderly having a high risk of sarcopenia are recommended.
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This study reports a new synthetic approach leading to N-arylbenzodthiazol-2-amine derivatives. Our synthetic method involves a S-alkylation reaction of variousbenzodthiazole-2-thiols ...and2-chloro-N-arylacetamides and a subsequent fragmentation step via Smiles rearrangement. This synthetic procedure is widely applicable, affords the N-arylbenzodthiazol-2-amine derivatives in good to excellent yields, and uses nontoxic and less expensive chemicals under mild condition.
A simple approach was developed for the rapid and accurate estimation of 5-day biochemical oxygen demand (BOD
5
) in food processing wastewater. Immobilization of the natural microbial consortium ...that was collected from an aerobic compartment of a food processing wastewater treatment plant was simply performed by adhesion using a low-cost porous carrier.
Pseudomonas aeruginosa
,
Bacillus cereus
, and
Streptomyces
, whose salt-tolerance and ability to break down organic compounds have been widely reported, were found to be predominant. These microorganisms may cause an enhancement of the bioreactor response in the presence of sodium chloride. Consequently, a modified glucose-glutamic acid (GGA) calibration standard was proposed in which an appropriate amount of NaCl was added; this solution was found to be more effective in terms of accuracy and practicality than both conventional GGA and the synthetic wastewater recipe from the Organisation for Economic Cooperation and Development (OECD). The calibrated self-built packed-bed bioreactor exhibited good precision of 3% or less in predicting BOD
5
in influent, which is similar to the performance of the most common commercial biochemical oxygen demand (BOD) bioreactors. There was a statistical agreement between the results obtained from this rapid BOD biosensor and the conventional methods, even when testing treated wastewater samples.
This study empirically explores the effects of bank funding diversity on Vietnamese commercial banks' profitability and risk in the context of the COVID-19 pandemic. The panel regression method was ...used to analyze quarterly data from 27 Vietnamese commercial banks from Q1-2016 to Q1-2021. The study findings demonstrate that commercial banks with diverse financing sources are more profitable and riskier. In the meanwhile, the COVID-19 outbreak did not diminish the short-term profitability of Vietnamese commercial banks, but it did increase their exposure to risk. On the basis of the empirical findings, this paper also proposes a number of strategies to assist Vietnamese commercial banks in operating more effectively and securely in the context of the COVID-19 pandemic.
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