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In health technology assessment (HTA), population-adjusted indirect comparisons (PAICs) are increasingly considered to adjust for the difference in the target population between studies. We aim to assess the conduct and reporting of PAICs in recent HTA practice, by performing, a methodological systematic review of studies implementing PAICs from PubMed, EMBASE Classic, Embase/Ovid Medline All, and Cochrane databases from January 1, 2010 to Feb 13, 2023. Four independent researchers screened the titles, abstracts, and full-texts of the identified records, then extracted data on methodological and reporting characteristics of 106 eligible articles. Most PAIC analyses (96.9%, n = 157) were conducted by (or received funding from) pharmaceutical companies. Prior to adjustment, 44.5% of analyses (n = 72) (partially) aligned the eligibility criteria of different studies to enhance the similarity of their target populations. In 37.0% of analyses (n = 60), the clinical and methodological heterogeneity across studies were extensively assessed. In 9.3% of analyses (n = 15), the quality (or bias) of individual studies was evaluated. Among 18 analyses using methods that required an outcome model specification, results of the model fitting procedure were adequately reported in three analyses (16.7%). These findings suggest that the conduct and reporting of PAICs are remarkably heterogeneous and suboptimal in current practice. More recommendations and guidelines on PAICs are thus warranted to enhance the quality of these analyses in the future.

This paper analyzes factors that affect the numeracy skills of secondary school students from mountainous and ethnic minority regions in Vietnam from the perspective of the students to create suitable strategies for teachers, parents, and the government to enhance their numeracy skills. Data from 755 students in 8 secondary schools in 8 provinces in the northern region of Vietnam were analyzed. The results showed eight factors that impact the numeracy levels of secondary students in mountainous regions. Student's efforts and language skills were most influential, and teachers did not have a substantial effect. The paper offers suggestions to equip teachers in these regions with more knowledge and skills to support students in developing their numeracy skills.

Ionization chambers were calibrated regarding absorbed dose to water in MeV X-ray fields of a medical linear accelerator, with nominal maximum energies of 6 MeV and 15 MeV. Whereas, absorbed doses to water at a depth of 10 cm below the water surface were measured using the same ionization chamber (referred to as IC-1) in two different manners (i.e., applying the old beam quality correction factor kQ0 from the old IAEA/TRS-398 protocol, referred to as D1-old10 and using the new one, kQ from the updated protocol, referred to as D1-new10. The calibration factors of IC-1, ND1,D,w, Q were deduced (for beam qualities Q of MeV X-ray fields with maximum energies of 6 MeV and 15 MeV). The identical procedure was applied to two other ionization chambers (IC-i, i=2,3) to obtain absorbed doses to water at a depth of 10 cm (referred to as Di-new10) using the new beam quality correction factor. A comparison between D1-new10 and Di-new10 was conducted to derive the calibration factors of the IC-i, NiD,w,Q. The combined standard uncertainties of NiD,w,Q (i =1,2,3) were estimated within 1.22% and 2.30%, respectively.

Gnetum formosum Markgr., a member of the Gnetaceae family, is distributed in Vietnam. This plant remains a botanical enigma with an unexplored diversity of chemical constituents and pharmacological effects. In this study, two new steroidal saponins, namely gnetumosides A (1) and B (2), were isolated from the aerial parts of G. formosum. Their chemical structures were elucidated using spectroscopic techniques, including high-resolution electrospray ionization mass spectrometry (HR-ESI-MS) and NMR, along with chemical hydrolysis and comparison with the reported literature. The potential anti-inflammatory effects of the isolated compounds were evaluated by measuring lipopolysaccharide-stimulated nitric oxide (NO) production in murine macrophage cells. Notably, compound 1 exhibited the most potent inhibitory activity (IC50 = 14.10 ± 0.75 µM), comparable to dexamethasone. Additionally, the mechanisms underlying the observed anti-inflammatory effects were investigated through molecular docking and molecular dynamics simulations on inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) proteins. This study is the first to investigate the chemical constituents and pharmacological effects of G. formosum.

Vodka constitutes a significant sector of Vietnam’s alcohol industry, including both domestic and imported varieties. However, this diversity faces challenges from illegal imports and adulterated products, threatening consumer health and brand integrity. This study employs Fourier transform infrared spectroscopy (FTIR) and inductively coupled plasma mass spectrometry (ICP-MS) to analyze 300 vodka samples from five brands collected across Hanoi. Significant variations were found in elemental compositions, with sodium concentrations ranging from 205.67 μg/L to 1269.24 μg/L and magnesium levels from 65.57 μg/L to 1453.34 μg/L. Principal Component Analysis (PCA) of the FTIR and ICP-MS data effectively differentiated the samples, with the first two principal components explaining 84.78% and 73.02% of the total variance, respectively. The PCA plots revealed distinct chemical profiles, notably isolating Rocket Vodka. These findings enhance food safety enforcement, protect consumer rights, and preserve brand reputations. The study underscores the importance of advanced analytical tools in combating beverage adulteration, ensuring public health, and maintaining market integrity, offering a replicable model for similar research in other regions.

Sausage is a convenient food that is widely consumed in the world and in Vietnam. Due to the rapid development of this product, the authenticity of many famous brands has faded by the rise of adulteration. Therefore, in this study, principal component analysis (PCA) was combined with chemical analysis to identify 6 sausage brands. Sausage samples were dried and then ground to a fine powder for both instrumental analyses of attenuated total reflectance-Fourier transform infrared (ATR-FTIR) and inductively coupled plasma–mass spectrometry (ICP-MS). Dried measurements of ATR-FTIR was performed directly on the ZnSe crystal, while elemental data were obtained through microwave digestion before the ICP-MS analysis. Principal component analysis (PCA) within the framework software of XLSTAT and STATISTICA 12 was performed on the spectroscopy and elemental dataset of sausage samples. PCA visualized the distinction of 6 sausage brands on both datasets of ATR-FTIR and ICP-MS. The classification on the spectroscopy profile showed that although more than 90% variation of the dataset was explained on the first two PCs, the difference between several brands was not detected as the distribution of data overlapped with one another. The PCA observation of the elemental composition on PC1 and PC3 has separated the sausage brands into 6 distinctive groups. Besides, several key elements contributed to the brands’ identification have been detected, and the most distinctive elements are Na, K, Ca, and Ba. PCA visualization showed the feasibility of the classification of sausage samples from different brands when combined with the results of FT-IR and ICP-MS methods. The experiment was able to differentiate the sausages from the 5 brands using multivariate statistics.

Electric bicycle is a vehicle which is used widely in all the citys and provinces of Vietnam. However, it’s hard to choose “the most suitable” or “the best” type of electric bicycle because each type has different criteria (parameters). To choose out the best option, we need to consider all the alternatives at once. That is called multi-criteria decision-making. This research used three multi-criteria decision-making methods include SAW method, MARCOS method and PSI method to choose from seven bestselling types of electric bicycle on the market in 2022. All the methods which were used chose out the same best electric bicycle type and the same worst bicycle type. And so, among seven types of electric bicycle which include M133 mini, M133 Sport 2022, Aima 133AM, Nijia – PA4, DK 133M, Yadea iGo and Yadea i3, the best type is Aima 133AM, in contrast, Yadea iGo is considered the worst type. Things that need to be done in the folowing researches were proposed in the last part of this paper.

Scanning trajectories are essential and important components of trajectory-based scanning and imaging systems such as laser scanning confocal microscopes, atomic force microscopes (AFM), laser scanning systems for aerial surveying (LiDAR), micro-electromechanical systems (MEMS), medical imaging and 2D/3D printing. Previous study has demonstrated that Sinusoidal Lissajous is the optimal scanning trajectory and proposed that increasing the scanning repetition could further enhance image quality. However, it is challenging to pinpoint the essential elements needed to enhance the quality of the reconstructed images since there is currently no comprehensive analysis of how the scanning trajectory resolution and scanning time affect the reconstructed image quality. The purpose of this work is to look into the influence of scanning resolution and scanning time on the quality of magnetic particle imaging (MPI)-reconstructed images across a variety of scanning trajectories. This study offers a comprehensive analysis of how scanning repetition and scanning time affect the reconstructed images' quality at the individual pixel in the field of view (FOV) as well as throughout the entire FOV. The impacts of the scanning time were investigated both before and after image reconstruction. In the pre-reconstruction phase, the minimum and maximum distances to the closest neighboring points in the FOV and their distribution in different regions of the FOV were analyzed in order to investigate the density, homogeneity, and time spent on each pixel. Here, we demonstrated that the image resolution for any scanning trajectory is scale invariance, meaning that for a fixed frequency ratio , the ratio of pixel size to image FOV size remains constant. Peak signal-to-noise ratio (PSNR), structural similarity index measure (SSIM), normalized root mean square error (NRMSE), and normalized sum of squared error (NSSE) are used to evaluate and compare the reconstructed images' quality in the post-reconstruction stage. It is found that the Sinusoidal Lissajous scanning trajectory is the best in terms of accuracy, structural similarity, and signal-to-noise. We showed that only the image quality for bidirectional Cartesian and sinusoidal Lissajous trajectories are sensitive to scanning time, particularly at the pixel scale. Furthermore, contrary to expectations, we discovered that optimizing the scanning repetition did not enhance the MPI-reconstructed image quality. Nevertheless, the image quality would be enhanced by extending the scanning duration through decreasing the scanning frequency. The optimal scanning frequency is half of the frequently used 25 kHz for the chosen ratio of 100. [ABSTRACT FROM AUTHOR]

The vision of the sixth generation of communication systems, commonly known as 6G, entails a connected world that provides ubiquitous connectivity and fosters the digital transformation of society. As the number of devices, services, and users continues to grow, intelligent solutions are expected to facilitate this transformation. This paper considers meta-learning as a pivotal paradigm for 6G systems, detailing its principles, algorithms, and theoretical underpinnings. The methodology involves integrating meta-learning with three potential 6G technologies: RF-based communication systems, optical communication systems, and molecular communication systems. The findings reveal the distinct characteristics of these technologies and demonstrate the potential benefits and challenges of incorporating meta-learning algorithms. Practical implications highlight how meta-learning can enhance the efficiency and adaptability of 6G systems, addressing the growing demand for intelligent and seamless communication networks. [ABSTRACT FROM AUTHOR]

In developing medical interventions using untethered milli- and microrobots, ensuring safety and effectiveness relies on robust methods for real-time robot detection, tracking, and precise localization within the body. The inherent non-transparency of human tissues significantly challenges these efforts, as traditional imaging systems like fluoroscopy often lack crucial anatomical details, potentially compromising intervention safety and efficacy. To address this technological gap, in this study, we build a virtual reality environment housing an exact digital replica (digital twin) of the operational workspace and a robot avatar. We synchronize the virtual and real workspaces and continuously send the robot position data derived from the image stream into the digital twin with short average delay time around 20–25 ms. This allows the operator to steer the robot by tracking its avatar within the digital twin with near real-time temporal resolution. We demonstrate the feasibility of this approach with millirobots steered in confined phantoms. Our concept demonstration herein can pave the way for not only improved procedural safety by complementing fluoroscopic guidance with virtual reality enhancement, but also provides a platform for incorporating various additional real-time derivative data, e.g., instantaneous robot velocity, intraoperative physiological data obtained from the patient, e.g., blood flow rate, and pre-operative physical simulation models, e.g., periodic body motions, to further refine robot control capacity. [ABSTRACT FROM AUTHOR]

This paper studies how to construct and compare various optimal portfolio frameworks for investors in the context of the Vietnamese stock market. The aim of the study is to help investors to find solutions for constructing an optimal portfolio strategy using modern investment frameworks in the Vietnamese stock market. The study contains a census of the top 43 companies listed on the Ho Chi Minh stock exchange (HOSE) over the ten-year period from July 2010 to January 2021. Optimal portfolios are constructed using Mean-Variance Framework, Mean-CVaR Framework under different copula simulations. Two-thirds of the data from 26/03/2014 to 27/1/2021 consists of the data of Vietnamese stocks during the COVID-19 recession, which caused depression globally; however, the results obtained during this period still provide a consistent outcome with the results for other periods. Furthermore, by randomly attempting different stocks in the research sample, the results also perform the same outcome as previous analyses. At about the same CvaR level of about 2.1%, for example, the Gaussian copula portfolio has daily Mean Return of 0.121%, the t copula portfolio has 0.12% Mean Return, while Mean-CvaR with the Raw Return portfolio has a lower Return at 0.103%, and the last portfolio of Mean-Variance with Raw Return has 0.102% Mean Return. Empirical results for all 10 portfolio levels showed that CVaR copula simulations significantly outperform the historical Mean-CVaR framework and Mean-Variance framework in the context of the Vietnamese stock exchange.

Bằng cách sử dụng kết hợp các phương pháp sắc ký, bốn hợp chất gồm friedelin (1), arborinol (2), isoarborinol (3) và stigmasterol (4) đã được phân lập từ phần trên mặt đất của cây Cơm rượu hoa nhỏ (Glycosmis parviflora (Sims) Little). Cấu trúc hóa học của chúng được xác định dựa trên phân tích dữ liệu phổ cộng hưởng từ hạt nhân (1D- và 2D-NMR) và so sánh với các tài liệu đã công bố. Các hợp chất (1-4) được phân lập lần đầu tiên từ cây Cơm rượu hoa nhỏ

Abstract Background Organisational culture (OC) has increasingly become a crucial factor in defining healthcare practice and management. However, there has been little research validating and adapting OCAI (organisational culture assessment instrument) to assess OC in healthcare settings in developing countries, including Vietnam. The purpose of this study is to validate the OCAI in a hospital setting using key psychometric tests and confirmatory factor analysis (CFA). Methods This is a cross-sectional study. Self-administered structured questionnaire was completed by 566 health professionals from a Vietnamese national general hospital, the General Hospital of Quang Nam province. The psychometric tests and CFA were utilized to detect internal reliability and construct validity of the instrument. Results The Cronbach’s alpha coefficients (α-reliability statistic) ranged from 0.6 to 0.8. In current culture, the coefficient was 0.80 for clan and 0.60 for adhocracy, hierarchy and market dimension, while in expected culture, the coefficient for clan, adhocracy, hierarchy, and market dimension was 0.70, 0.70, 0.70 and 0.60, respectively. The CFA indicated that most factor loading coefficients were of moderate values ranging from 0.30 to 0.60 in both current and expected culture model. These models are of marginal good fit. Conclusions The study findings suggest that the OCAI be of fairly good reliability and construct validity in measuring four types of organisational culture in healthcare setting in resource-constrained countries such as Vietnam. This result is a first step towards developing a valid Vietnamese version of the OCAI which can also provide a strong case for future research in the field of measuring and managing organisational culture.

Mitreola sphaerocarpa (Loganiaceae), a species occurring in Peninsular Malaysia, is newly reported for the flora of Vietnam. The description, photographs, information on ecology, preliminary conservation status and taxonomic notes are also presented. In order to facilitate identification, we provide an identification key and checklist for the 4 known Mitreola species in Vietnam. [ABSTRACT FROM AUTHOR]

Vodka constitutes a significant sector of Vietnam's alcohol industry, including both domestic and imported varieties. However, this diversity faces challenges from illegal imports and adulterated products, threatening consumer health and brand integrity. This study employs Fourier transform infrared spectroscopy (FTIR) and inductively coupled plasma mass spectrometry (ICP‐MS) to analyze 300 vodka samples from five brands collected across Hanoi. Significant variations were found in elemental compositions, with sodium concentrations ranging from 205.67 μg/L to 1269.24 μg/L and magnesium levels from 65.57 μg/L to 1453.34 μg/L. Principal Component Analysis (PCA) of the FTIR and ICP‐MS data effectively differentiated the samples, with the first two principal components explaining 84.78% and 73.02% of the total variance, respectively. The PCA plots revealed distinct chemical profiles, notably isolating Rocket Vodka. These findings enhance food safety enforcement, protect consumer rights, and preserve brand reputations. The study underscores the importance of advanced analytical tools in combating beverage adulteration, ensuring public health, and maintaining market integrity, offering a replicable model for similar research in other regions. [ABSTRACT FROM AUTHOR]

Mangrove plant endophytic bacteria are prolific sources of bioactive secondary metabolites. In the present study, twenty-three endophytic bacteria were isolated from the fresh roots of the mangrove plant Rhizophora apiculata. The identification of isolates by 16S rRNA gene sequences revealed that the isolated endophytic bacteria belonged to nine genera, including Streptomyces, Bacillus, Pseudovibrio, Microbacterium, Brevibacterium, Microbulbifer, Micrococcus, Rossellomorea, and Paracoccus. The ethyl acetate extracts of the endophytic bacteria’s pharmacological properties were evaluated in vitro, including antimicrobial, antioxidant, α-amylase and α-glucosidase inhibitory, xanthine oxidase inhibitory, and cytotoxic activities. Gas chromatography–mass spectrometry (GC-MS) analyses of three high bioactive strains Bacillus sp. RAR_GA_16, Rossellomorea vietnamensis RAR_WA_32, and Bacillus sp. RAR_M1_44 identified major volatile organic compounds (VOCs) in their ethyl acetate extracts. Genome analyses identified biosynthesis gene clusters (BGCs) of secondary metabolites of the bacterial endophytes. The obtained results reveal that the endophytic bacteria from R. apiculata may be a potential source of pharmacological secondary metabolites, and further investigations of the high bioactive strains—such as fermentation and isolation of pure bioactive compounds, and heterologous expression of novel BGCs in appropriate expression hosts—may allow exploring and exploiting the promising bioactive compounds for future drug development.

Helicteres hirsuta Lour. is a traditional Vietnamese medicine for treating chronic liver diseases such as cirrhosis and liver cancer. Many in vitro and in vivo experiments have demonstrated that the extracts and isolated compounds from H. hirsuta have diverse pharmacological activities, including antioxidant, anti-inflammatory, and anti-cancer effects. However, the hepatoprotective effects have not been reported until now. Therefore, the methanolic and ethanolic extracts of the aerial part of the H. hirsuta L. (HHM and HHE-1/1) were examined on liver fibrosis induced by carbon tetrachloride (CCl4) in rats for the first time. The results revealed that all the livers of the model group had stage F4 cirrhosis; the group that received silymarin, and HHM and HHE-1/1 had milder liver damage cirrhosis stage F1-F2 which implies that the methanolic and ethanolic extracts of H. hirsute have a definite advantage in the development of food or oral medications for hepatoprotective activity.