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Tuberculosis (TB) is a serious global public health problem. Detecting the changes of adenosine deaminase (ADA), interleukin (IL)-1β, IL-2, tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ) released from macrophages and monocytes is greatly valuable in the diagnosis of TB. Hence, this study was designed to determine the optimal cut-off points of ADA, IL-1β, IL-2, TNF-α, and IFN-γ, allowing to differentiate pleural TB (PLTB), peritoneal TB (PTB), and meningeal TB (MTB). The study included 386 patients with pleural effusion, 47 patients with peritoneal effusion, and 134 patients with encephalitis and meningoencephalitis suspect of TB. ADA was determined by an enzyme kinetics method; cytokine concentration was measured by a test based on the competitive enzyme-linked immunosorbent assay principle. Sensitivity, specificity, and positive and negative predictive value were calculated and described. In the aspiration fluid, ADA activity was greatly different between PLTB, PTB, and MTB groups with values of 37.5 U/L, 30.5 U/L, and 8.1 U/L and sensitivity and specificity of 87.7% and 83.4%; 100% and 88.9%; 97.3% and 98.6%, respectively. Similar, IFN-γ concentrations were distinctively different between PLTB, PTB, and MTB patients (with values of 120 pg/mL, 200 pg/mL, and 30 pg/mL with sensitivity and specificity of 80.3% and 80.9%; 80.0% and 92.6%; 98.6% and 61.7%, respectively). The determination of ADA and IFN-γ levels in the aspiration fluid is potentially considered a highly sensitive and specific test for differentiating PLTB, PTB, and MTB.

In this work, 31.4 wt.% Ni/SBA-15 (Ni/SBA-15) nonpromoted and alkalized with ammonia solution and by MgO promoter catalysts were prepared and used for combined steam and CO2 reforming of CH4 (bireforming). Effect of concentration of ammonia solution (NH3(aq)) (10–25 vol.%) and Mg content (3–12 wt.%) on the properties of the Ni/SBA-15 catalysts was investigated by low-angle and powder X-ray diffraction (XRD), N2-BET isothermal adsorption, SEM, TEM, EDS mapping, H2-TPR, and CO2-TPD methods. The performance of the catalysts in bireforming was assessed in the temperature range of 550–800°C. The enhancement of dispersion of NiO particles, reducibility, and basicity of alkalized Ni/SBA-15 catalysts were responsible for improving the catalytic performance of this catalyst. The results revealed that the Ni/SBA-15 treated with 15-25% NH3(aq) solution and promoted with 3-9% Mg exhibited high activity for CH4 conversion. Meanwhile, Ni6Mg/SBA-15 showed the highest CO2 conversion. Among tested catalysts, Ni/SBA-15-20NH3 and Ni9Mg/SBA-15 samples had an almost equal activity with a CH4 conversion of nearly 97% and a CO2 conversion of about 84% at 700°C thanks to its moderate affinity with both CO2 and CH4. However, the H2/CO ratio of the product mixture remained at 2.02 on the Ni/SBA-15-20NH3 catalyst and almost 1 on the Ni9Mg/SBA-15 sample. These results might be related to the fact that the alkalization of the Ni/SBA-15 catalyst by NH3(aq) solution had an advantage over using MgO because side reactions were unlikely to occur. [ABSTRACT FROM AUTHOR]

Máy cắt ống Plasma được xem là một sản phẩm khá hoàn hảo trong lĩnh vực cắt thép hình với tốc độ cắt cao, cắt được nhiều loại mẫu, quy cách khác nhau, hiệu quả chuyển đổi năng lượng cao hơn hẵn so với khi cắt oxy-gas truyền thống. Phần mềm điều khiển đi kèm các tính năng về gia công được tích hợp sẵn trên máy giúp người vận hành dễ dàng sử dụng và chi phí bảo trì rất thấp. Trong bài báo này, tác giả đề xuất một phương án thiết kế và chế tạo máy cắt ống Plasma CNC 4 trục với khả năng cắt các loại ống hình tròn, vuông, chữ nhật và oval. Máy có kích thước tổng thể là 3500×520×1600 mm có khả năng cắt phôi với đường kính lên đến 100 mm, chiều dài tối đa 3 m và chiều dày tối đa 5 mm. Động cơ bước được sử dụng để làm động cơ dẫn động cho cả 4 trục. Nguồn cắt sử dụng là HYLONG CUT-40H với dòng điện tùy chỉnh trong khoảng 20 - 40A để phù hợp với chiều dày vật liệu cắt.

Zinc–air batteries are promising candidates as stationary power sources because of their high specific energy density, high volumetric energy density, environmental friendliness, and low cost. The oxygen-related reactions at the air electrode are kinetically slow; thus, the air electrode integrated with an oxygen electrocatalyst is the most critical component, and inevitably determines the performance of a Zn–air battery. The aim of this paper was to document progress in researching bifunctional catalysts for Zn–air batteries. The catalysts are divided into several categories: noble metal, metal nanoparticle (single and bimetallic), multicomponent nanoparticle, metal chalcogenide, metal oxide, layered double hydroxide, and non-metal materials. Finally, the battery performance is compared and discussed.

Human resources have an essential meaning in stability and sustainability of business activities. The quality of human resources contributes to increasing intelligence and thinking, as well as productivity and efficiency in all activities of an enterprise. The study aims to determine the influence of different factors on Vietnamese enterprises’ human resources management, including staffing plans, personnel selection, employee use, resource training, employee rating, and bonus policies. Exploratory factor analysis is employed to test the factors related to the research model. The sample comprises 417 leaders working at Vietnamese enterprises surveyed in 2021. The paper uses panel data to test the regression using OLS method. The selected enterprises are diverse in industry and size to ensure representativeness and are based in Ho Chi Minh City. The results elicit that staffing plans and bonus policies are two of the six factors that positively affect the human resources management of Vietnamese enterprises. The findings also show that staffing plans are the factor that has the most substantial impact on human resources management. Finally, the paper has proposed some policy suggestions to stabilize human resources management at Vietnamese enterprises to attract quality talent.

Financial reporting of enterprises has important implications for information users. The timely provision of financial reporting by enterprises helps investors to make appropriate business decisions. The purpose of the paper is to test the influence of the factors on the timeliness of financial reporting of the Vietnamese listed enterprises. The timeliness of financial statements is determined by the total number of days of difference between the date of signing the audit report and the end of the financial year. The sample includes the top 100 best-listed enterprises of the Vietnamese stock market. The paper uses time series with panel data. The data are collected from annual and financial reports for the period from 2016 to 2020. The paper performs quantitative research to test the hypotheses. The results verify two factors, such as return on equity and audit type, have a negative effect on the timeliness of financial reporting. Audit type has the most influence on timeliness. Research also shows some listed enterprises have not yet complied with regulations on timely information disclosure. The paper proposes some appropriate policies for Vietnamese listed enterprises to ensure the timeliness of information.

In this study, Ce1-xLaxNiO3 catalysts (x = 0.2, 0.4, 0.6, and 0.8) and Ce1-xLaxNiO3 on porous silica were prepared by co-precipitation. The effect of the La content on the catalytic activity in methane bi-reforming was investigated in the temperature range of 550 °C-750 °C. The physicochemical properties of the prepared catalysts were analysed by several methods, including X-ray diffraction, hydrogen temperature-programmed reduction, CO2 temperature-programmed desorption, N2 adsorption isotherm, energy-dispersive X-ray spectroscopy, Raman spectroscopy, scanning electron microscopy and high-resolution transmission electron microscopy. From the research results, the suitable substitution rate of La in Ce1-xLaxNiO3 was found to be x = 0.4; its conversions of CH4 of 94% and CO2 of 92% were achieved at 700 °C and GHSV 30000 mL/(g.h). However, the intense coke accumulation on Ce0.6La0.4NiO3 limited its development. The porous silica carrier improved the structure and properties of the Ce0.6La0.4NiO3 catalyst. The SiO2-supported catalyst (Ce0.6La0.4NiO3/SiO2) showed excellent stability and coke resistance, which had stable activity for 100 h of time on stream, structure stability and low coke accumulation; 2.37 mgC/gcat formed after 100 h (coke formation rate of 0.02 mmolC/(gcat.h)), which demonstrated that it was one of the best coke-resistant perovskite catalysts for the BRM reaction. The large surface area of silica and strong interaction of Ni with metal oxide reduced the metal Ni particle size to the threshold size (2−4 nm), where the strongly reduced coke accumulation, high basicity, and vacancy oxygen content of CeO2 and La2O3 were considered major contributors to the high activity and exceptional coke resistance. The high structural stability, anti-sintering performance and high coke resistance all contributed to the excellent durability of the Ce0.6La0.4NiO3/SiO2 catalyst. This work provides a new resolution for the development of coke-resistant perovskite catalysts for methane reforming.

In the trend of globalization, profit is always a concern for companies because the competition is increasingly fierce. With accounting tools and policies, managers of companies can perform profit management. The purpose of this paper is to test the influence of the board of directors on the discretionary accruals in Vietnamese listed companies. The paper uses time series of table data. The sample includes 915 observations of 183 Vietnamese non-financial companies in the period from 2016 to 2020. The feasible generalized least squares method is used to test the hypotheses of the research model. The paper uses two foundational theories, including the agency theory and the signaling theory, to explain the discretionary accruals of Vietnamese listed companies. The results show that the independence of the board of directors, the meetings of the board of directors, and the foreigners in the board of directors influence the discretionary accruals in Vietnamese listed companies. Then, the paper proposes some appropriate policies on regulations to control the discretionary accruals in Vietnamese listed companies to improve the quality of accounting information in the context of regional and international economic integration.

Information from financial reports plays an important role for stakeholders in making business decisions. The information efficiency is even more meaningful when it is relevant and useful to users. The purpose of the paper is to examine the impact of control activities on the information efficiency of the financial reports of Forbes enterprises in Vietnam. The paper uses time series data and the sample includes 250 observations from 2016 to 2020. The paper uses ordinary least squares to experimentally test hypotheses. The results indicate there are two factors out of four that have a negative impact on the information efficiency of financial reports, including control activity members and female members of the control activities. The control activity members have a higher impact than female members. To enhance the information efficiency of Forbes enterprises’ financial reports, Vietnamese state agencies should strengthen control and supervision of legal regulations so that Forbes enterprises can raise awareness on the information efficiency of financial reports.

This work offered insights into the characteristics and performance of nickel nanocatalyst in situ synthesized through CeNiO3 perovskite for the bireforming of methane (BRM). Effects of calcination conditions on the characteristics of CeNiO3 structure and on the reduction regime of the as-prepared perovskite on the physicochemical properties and performance of nickel catalyst in BRM were assessed. The formation of high-crystallinity CeNiO3 at temperatures above 700 °C was confirmed. The synthesized CeNiO3 existed in the form of spherical particles 20–40 nm in size and uniformly distributed. Among the samples, one calcined at 700 °C for 2 h (C-700-2.0) had the smallest and the most uniform particle and the highest reducibility. This sample was found to be the optimum precursor for the in situ synthesis of a highly effective nano-Ni catalyst for BRM. The reduction mode significantly affected the catalytic performance of the C-700-2.0 precursor. The sample reduced at 750 °C for 1.5 h (R-750-1.5) possessed the optimum activity, with conversions of CH4 and CO2 reaching equilibrium (98% and 84%, respectively) and an ideal H2/CO ratio of 2 at the reaction temperature of 700 °C.

The influence of the calcination mode of sol–gel synthesis on the crystallization properties of ferric pseudobrookite Fe2TiO5 (FTO) was investigated. The characteristics of pseudobrookite were identified by various methods: TGA, XRD, FT-IR, BET adsorption, EDX, EDS mapping, Raman spectroscopy, UV-Vis, SEM, and TEM. The results indicate that ferric pseudobrookite crystals can be fabricated at a low calcination temperature of 600 °C and that crystallization can be controlled by the calcination regime. Calcination at 700 °C for 2 h creates the sample with the highest crystallinity and smallest crystal (31.3 nm) and particle size (20–35 nm). With its main components of ferric Fe2TiO5 and rutile TiO2, pseudobrookite can absorb visible light up to 653 nm and UV-A light with wavelengths shorter than 450 nm. The activity of the FTO obtained was estimated from the removal of phenolic acid in photocatalytic and photo-Fenton reactions under UV-A light irradiation using a batch method. The results show that Fe2TiO5 appears to be an excellent catalyst in a photo-Fenton process to decompose cinnamic acid (CA). The maximum CA conversion reached 96.2% after 280 min in a photo-Fenton process at pH 3.0, which is a much higher rate of conversion than in a photocatalytic reaction in air (20.0%). Further, Fe2TiO5 exhibits excellent stability in an acidic medium (pH = 3.0) and can easily be recovered and used repeatedly with stable performance. After ten batches of photo-Fenton reaction, CA conversion decreases by 10% and the catalyst structure is almost unchanged.