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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]

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.

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.

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.

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.

Today, knowledge becomes an important resource for any enterprise to improve their competitiveness. In Vietnam, although knowledge management (KM) is not popular, many enterprises, big or small, begin to focus on facilitating knowledge sharing between their employees. To increase competitiveness of Vietnamese enterprises, especially for SMEs –the most dynamic sector of Vietnam economy, encouraging knowledge sharing (KS) between employees is one of the most useful solutions. However, previous research showed that knowledge sharing was affected by organizational culture. Therefore, this research focused on exploringcultural factors affecting on knowledge sharing. Sample data were collected from 418 employees, who work for SMEs located in HCMC, Vietnam. Analysis results showed that knowledge sharing of Vietnamese SMEs was affected by these factors: Openness (beta=0.280), Team orientation (beta=0.248), Output orientation (beta=0.166), and Organizational structure (beta=0.097). Based on these results, some managerial implications for improving the effectiveness of knowledge sharing in Vietnamese SMEs are suggested. These implications will help Vietnamese SMEs to improve knowledge management efficiency and their competitiveness.

This study explores the adjustment process of capital structure using dynamic model, by which capital structures are adjusted towards optimal level, and cost of adjustment has impacts on dynamic adjustment speed of capital structure. Adjustment speed within a range of [0;1] shows an evidence for adjustment and partial adjustment behaviors of capital structure. The evidence for partial adjustment shows that cost of adjustments does exist. This research shows that growth and size have positive impacts, meanwhile distance from optimal capital structure has negative impact, on adjustment process. Data in this analysis is balanced panel data of companies listed on HOSE and HNX exchanges. The OLS and GMM estimations were used to test the proposed models.

This research was carried out to investigate the behavior of thin prestressed slab beams (TPSBs) that are part of the Department of Transportation's inventory, including TxDOT. Fourteen TPSBs were tested to study the structural behavior and the effects of several variables, such as height, cast-in-place deck, shear span-depth ratio (a/d), prestressing steel ratio, transverse steel ratio, and longitudinal reinforcement at the prestress-transfer zone. The tests showed that shear was not the predominant failure mode, even under very small shear span-depth ratios (a/d ≈ 1.2). In most cases, failures of TPSBs were governed by either anchorage bond or flexure. When compared to the current building and bridge codes, the test results showed that both ACI 318 and AASHTO LRFD cannot predict the strength and the failure mode of TPSBs reasonably. As a result, a design equation is derived based on anchorage bond and flexural capacities. [ABSTRACT FROM AUTHOR]

Age-related macular degeneration (AMD) is a leading cause of vision loss, characterized by drusen deposits and thickened Bruch's membrane (BM). This study details the capacity of nanosecond laser treatment to reduce drusen and thin BM while maintaining retinal structure. Fifty patients with AMD had a single nanosecond laser treatment session and after 2 yr, change in drusen area was compared with an untreated cohort of patients. The retinal effect of the laser was determined in human and mouse eyes using immunohistochemistry and compared with untreated eyes. In a mouse with thickened BM (ApoEnull), the effect of laser treatment was quantified using electron microscopy and quantitative PCR. In patients with AMD, nanosecond laser treatment reduced drusen load at 2 yr. Retinal structure was not compromised in human and mouse retina after laser treatment, with only a discrete retinal pigment epithelium (RPE) injury, and limited mononuclear cell response observed. BM was thinned in the ApoEnull mouse 3 mo after treatment (ApoEnull treated 683 ± 38 nm, ApoEnull untreated 890 ± 60 nm, C57Bl6J 606 ± 43 nm), with the expression of matrix metalloproteinase-2 and -3 increased (>260%). Nanosecond laser resolved drusen independent of retinal damage and improved BM structure, suggesting this treatment has the potential to reduce AMD progression. [ABSTRACT FROM AUTHOR]

PurposeTo investigate the possible roles of retinal photoreceptors in macular oedema and retinal angiogenesis with particular reference to the mode of action of laser therapy.Methods(i) Studies in rats made hypoxic for 2 h by administering an oxygen/nitrogen mixture of reduced oxygen content, and growth factors determined by RT-PCR, western blotting, and immunohistochemistry. Assessment of blood–retinal barrier integrity using fluorescent and electron-dense tracers. (ii) Studies in pigs with one retina made hypoxic by selective embolisation of the retinal capillary circulation with fluorescent microspheres. (iii) Assessment of laser therapy in selected cases of retinal neovascularisation indicating a role for photoreceptors.ResultsIn the hypoxic retina, angiogenic and vascular permeability factors such as vascular endothelial growth factor (VEGF), nitric oxide synthases (NOSs), and insulin-like growth factor-1 are upregulated in retinal astrocytes and Müller cells but are also present in large amount in the photoreceptors. Hypoxia-inducible factor-1 (HIF-1) is upregulated in retinal glial cells but not in the photoreceptors, suggesting that growth factors in the photoreceptors may not have been generated there. The tracer dye, rhodium isothiocyanate, leaking from an abnormally permeable inner blood–retinal barrier in the hypoxic retina accumulates in the photoreceptors.ConclusionsThe results indicate that laser treatment of macular oedema or retinal neovascularisation may obtain its effect not only by improving oxygen availability in the inner retina, but also by reducing the load of angiogenic/permeability factors that accumulate in the photoreceptors in hypoxic/ischaemic conditions. [ABSTRACT FROM AUTHOR]

AimsTo determine the correlation between systemic corticosteroid therapy and the occurrence and size of peripapillary atrophy (PPA) in patients with Vogt–Koyanagi–Harada (VKH) disease.MethodsAll patients with VKH disease were retrospectively reviewed for their corticosteroid regimen. The extent of the PPA, if present, was measured using digitized imaging software, by two masked observers. Eyes with myopia greater than 6 dioptres or glaucoma were excluded. The patients were classified into three groups: early high (EH), late high (LH), and low dose (LD), according to the dose and timing of corticosteroids received during the acute phase of the disease.ResultsThere were 40 eyes in the EH group, 25 eyes in the LH group, and 23 eyes in the LD group. Multivariate analysis showed that corticosteroid therapy was the main determinant of PPA occurrence. All the eyes in the LD group had PPA and eyes in the LH groups were 4.02 times (95% confidence interval 1.24–13.07) more likely to develop PPA than those in the EH group. The LD group also had larger PPA to disc ratios than the EH group. (Mean of 2.83 vs0.19, P<0.001)ConclusionThe development and extent of PPA in patients with VKH disease appear to be dependent on the dose and timing of systemic corticosteroids.Eye (2008) 22, 240–245; doi:10.1038/sj.eye.6702591; published online 15 September 2006 [ABSTRACT FROM AUTHOR]

Alice Brandli, Chi D Luu, Robyn H Guymer, Lauren N Ayton Centre for Eye Research Australia, Department of Surgery (Ophthalmology), The University of Melbourne, Royal Victorian Eye and Ear Hospital, Melbourne, VIC, Australia Abstract: Vision prostheses, or “bionic eyes”, are implantable medical bionic devices with the potential to restore rudimentary sight to people with profound vision loss or blindness. In the past two decades, this field has rapidly progressed, and there are now two commercially available retinal prostheses in the US and Europe, and a number of next-generation devices in development. This review provides an update on the development of these devices and a discussion on the future directions for the field. Keywords: vision prostheses, bionic eye, vision restoration, blindness, medical bionics, retinitis pigmentosa

Mục tiêu của nghiên cứu là nhằm xây dựng một quy trình tối ưu hóa cho việc sản xuất biodiesel từ dầu thầu dầu thông qua phản ứng transester hóa với xúc tác base. Phản ứng được thực hiện dưới sự thay đổi các thông số như: tỷ lệ mol methanol: dầu (4:1-8:1), nồng độ chất xúc tác (0.25-1.50%), nhiệt độ (40-60°C) và thời gian phản ứng (45-150 phút). Hiệu suất cực đại của phản ứng đạt được tại các điều kiện: tỷ lệ mol methanol:dầu, 6:1; nồng độ xúc tác potassium hydroxide, 0.5%; tốc độ khuấy trộn, 500 vòng/phút; nhiệt độ phản ứng 60oC và thời gian phản ứng, 120 phút. Hiệu suất tối ưu đạt được dưới những điều kiện này là 95.84%. Chất lượng của biodiesel được đánh giá thông qua các đặc tính hóa lý quan trọng như độ nhớt động học ở 40°C, nhiệt lượng tổng, chỉ số acid, ăn mòn lá đồng ở 50°C. Tuy nhiên, độ nhớt động học ở 40°C của diesel sinh học từ dầu thầu dầu quá cao không phù hợp để sử dụng trực tiếp cho động cơ đốt trong, vì thế, sự pha trộn biodiesel với nhiên liệu diesel được thực hiện và đánh giá. Kết quả cho thấy độ nhớt động học ở 40°C của hỗn hợp biodiesel từ dầu Thầu dầu và diesel thỏa mãn các tiêu chuẩn ASTM D6751 (1.9-6.0 mm2/s) và EN 14214 (3.5-5.0 mm2/s).

Một quy trình tổng hợp dầu diesel sinh học từ dầu mù u gồm ba giai đoạn đã được thực hiện trong nghiên cứu này. Dầu mù u thô được xử lý sơ bộ với methanol được thực hiện trong giai đoạn đầu tiên. Trong giai đoạn hai, quá trình ester hóa xúc tác acid nhằm để làm giảm chỉ số acid của dầu mù u về giá trị thấp hơn 2% đã được tiến hành. Giai đoạn cuối cùng là quá trình transester hóa xúc tác base nhằm chuyển sản phẩm của giai đoạn hai thành mono-ester (biodiesel) và glycerol. Những yếu tố quan trọng ảnh hưởng đến hiệu suất của quá trình tổng hợp như tỉ lệ mol (methanol/oil), hàm lượng xúc tác, nhiệt độ và thời gian phản ứng đã được nghiên cứu. Từ kết quả nghiên cứu, hiệu suất tổng hợp đạt được trên 90% dưới điều kiện nhiệt độ 60oC, tỉ lệ mol 6:1 (methanol/oil), hàm lượng xúc tác 1% (catalyst/oil), thời gian phản ứng là 2 giờ và tốc độ khuấy 600rpm. Kết quả phân tích GC-MS cho thấy, methyl oleate (C18:1) và methyl linoleate (C18:2) là hai thành phần chính của dầu diesel sinh học tổng hợp từ dầu mù u (CaloBDF). Những tính chất quan trọng của biodiesel như nhiệt lượng tổng, điểm chớp cháy và độ nhớt động học ở 40oC đã được phân tích và so sánh với giá trị của những đại lượng tương ứng của dầu diesel.

Các tính chất hóa lý của xúc tác trước phản ứng và sau phản ứng trong các điều kiện khác nhau: không có tạp chất, có hơi nước, và có khí H2S được nghiên cứu bằng các phương pháp BET (BRUNAUER-EMMETT-TELLER), chuẩn độ xung, khử chương trình nhiệt độ (TPR). Kết quả nghiên cứu cho thấy xúc tác có hoạt tính cao khi kích thước tinh thể đạt giá trị tối ưu 135-325A0. Nguyên nhân giảm hoạt tính của xúc tác là do các ion kim loại trong xúc tác bị khử tạo nên những tinh thể có kích thước quá lớn. Chất mang không ảnh hưởng đến cấu trúc của xúc tác mà có vai trò quan trọng trong việc cản trở quá trình khử các oxit kim loại trong xúc tác làm cho xúc tác có độ bền làm việc cao.