Search

The aims of this research is to evaluate the impact of Environmental, Social and Governance (ESG) information disclosure (using both financial and non-financial information) on stock prices of businesses in Vietnam; From there, propose recommendations to promote transparent practices and information disclosure about ESG of businesses related activities; Contribute to developing sustainable investment goals in businesses, and the financial market in general. Based on the (Ohlson, 1995) [40] valuation model, and developed by Barth and Clinch (2009) [41] the research was conducted empirically in 30 listed companies in Vietnam in the period 2019–2022. Research results based on the GLS method show that ESG positively impacts stock prices. Additionally, this paper conducted an in-depth analysis of each individual pillar and found that the environmental pillar was considered the most meaningful to market participants. However, the correlation between ESG and stock prices is weakened for environmentally sensitive businesses. This study also makes a valuable contribution to the current literature on non-financial information reporting by using manually collected data and investigating the effects of ESG reporting on market participants in the public system voluntary information disclosure system of an emerging market like Vietnam.

Purpose – This paper examines the political budget cycles in emerging and developing countries using a sample of 91 countries from 1992 to 2019. Design/methodology/approach – This paper employs a pooled ordinary least squares (OLS) model with clustered standard errors at the country level. To address endogeneity issues, the authors also employ a two-step system generalized methods of moments model. Findings – The authors find clear evidence of political budget cycles in emerging and developing countries. The authors consistently find that incumbents increase total government spending, particularly in economic affairs, public services and social welfare, in the year before an election and the election year. In contrast, they contract spending in the year after an election. Research limitations/implications – Policymakers should be aware of the political budget cycles during election years. Promoting control of corruption and democracy helps to alleviate the effects of the political budget cycles in emerging and developing countries. Originality/value – The authors are among the first to explore the political budget cycles in emerging and developing countries by focusing on the total government spending and its main compositions, including expenditures on economic affairs, public services and social welfare. Besides, the authors also explore the conditioning effects of control of corruption, political ideology and democracy.

BackgroundMyocardial injury is a prevalent complication observed in patients hospitalized with COVID-19 and is strongly associated with severe illness and in-hospital mortality. However, the long-term consequences of myocardial injury on clinical outcomes remain poorly understood. This study aimed to assess the impact of myocardial injury on both acute-phase and long-term prognosis in COVID-19 patients.MethodsA retrospective, observational study was conducted on all patients who received treatment at the Intensive Care Center for COVID-19 patient, University Medical Center Ho Chi Minh City (UCICC), from August 3rd, 2021, to October 28th, 2021.ResultsA total of 582 patients were enrolled in the study, of which 55.3% were female. The mean age of participants was 63.3 ± 16.2. Out of these patients, 330 cases (56.8%) showed myocardial injury. Compared to patients without myocardial injury, those with myocardial injury were older and had a higher incidence of chronic diseases including hypertension, ischemic heart disease, atrial fibrillation, heart failure, diabetes mellitus, chronic kidney disease. They also presented with more severe respiratory failure upon admission and showed a more pronounced abnormality in inflammation and kidney function tests. Furthermore, the in-hospital mortality rate was significantly higher in the group with myocardial injury (49.7% vs 14.3%, p

Purpose – This purpose of this paper is to understand residents’ choice of preferred measures and their willingness-to-pay (WTP) for the measures to improve the air quality of Hanoi city. Design/methodology/approach – Questionnaire surveys were conducted to collect the opinions of 212 household representatives living in Hanoi City. The survey tools were tested and adjusted through an online survey with 191 responses. Multivariate probit and linear regression models were used to identify determinants of respondents’ choices of measures and their WTP. Findings – Respondents expressed their strong preferences for three measures for air quality improvements, including: (1) increase of green spaces; (2) use of less polluting fuels; (3) expansion of public transportation. The mean WTP for the implementation of those measures was estimated at about 148,000–282,000 Vietnamese dong, equivalent to 0.09–0.16% of household income. The respondents’ choices appear to be consistent with their characteristics and needs, such as financial affordability, time on roads and their perceived impacts of air pollution. The WTP estimates increase with perception of air pollution impacts, time on roads, education and income; but are lower for older people. Practical implication – Increase of green spaces can be the measure to which policy makers should pay more attention. The match-up of residents needs and well-informed plans will be an important key to success. Originality/value – This appears to be the first attempt to test the validity of public opinions on choices of measures for improving urban air quality in Vietnam. Our WTP estimates also contribute to the database on the values of improved air quality in the developing world.

Vaccines are strongly recommended globally as an effective measure to prevent serious illness from and spread of COVID-19. Concerns about safety following vaccination continue to be the most common reason that people do not accept the vaccine. This retrospective study was carried out on 4341 people who received the first dose of ChAdOx1 nCoV-19, BBIBP-CorV, or mRNA-1273 vaccine at Jio Health Clinic in Ho Chi Minh City, Vietnam. Post-injection side effects were either reported by participants or actively collected by health care staff by means of telemedicine. Local side effects were reported by 35.5% of all individuals, with pain being the most common symptom (33.3%). Systemic side effects were reported by 44.2% of individuals, with fever (25.3%) and fatigue (21.4%) being the most common. Age ≤60 years, female gender, and ChAdOx1 nCoV-19 were significant independent risk factors for both local and systemic side effects, while a history of allergy was significant as a risk factor for local side effects. A total of 43 individuals (1.0%) reported concerning symptoms of rare severe complications, which were addressed and treated by physicians via Jio Health app.

Interactive virtual reality (VR) services such as VR gaming require considerable computing power for rendering higher quality VR images at a high frame rate. Thus offloading such VR processing to a cloud or edge computing entity is promising, but is accompanied by long latency leads for a user to see an image of the past viewport, resulting in prohibitive motion sickness. Time warp is a technique for VR that warps a rendered image before scanning it out to the display to correct for the head movement occurring after the rendering and will play an important role in reducing the perceived latency in cloud/edge VR. However, time warp has to be applied to the image areas excluding the head-locked objects such as head-up display, menu bar, and notification that are intended to have a fixed position on a screen; otherwise, they are shown to judder. In this paper, we propose an algorithm that identifies head-locked objects in encoded VR frames at low computational load with no explicit information of the head-locked objects for selective time warp in the cloud/edge VR environments. First, we make a key observation from testbed experiments that motion vectors embedded in an encoded VR video stream are highly correlated with the user’s head motion. Based on this finding, the head-locked object detection algorithm is designed to: 1) find a raw shape of each head-locked object from motion vectors embedded in frames and 2) identify the exact pixel-level head-locked region within a limited search area (along the boundary of each raw shape) by monitoring pixel color changes over frames. In order to achieve even lower computational load, the costly part of the algorithm is activated only when a new head-locked object appears. The experimental study demonstrates that the algorithm is able to detect multiple head-locked objects with zero pixel error under limited computational load.

Bored PHC nodular piles (BPNP) are an eco-friendly and advantageous option for pile foundations of medium-rise to high-rise buildings. As none of the current methods to estimate the ultimate axial load-bearing capacity is accurate enough for BPNP in engineering practice, this study aims to achieve that objective by developing a new direct SPT method. To that end, we use static pile load test and SPT data of 81 PHC nodular piles collected in Vietnam. The ultimate bearing capacity is interpreted from the load–displacement curve in pile static load tests by various methods to determine the most suitable method for the nodular piles. Furthermore, 8 methods to determine axial load pile capacity directly from the standard penetration test are examined. Each method’s effectiveness is evaluated by comparing its predicted values with the measured values. Finally, the genetic algorithm for function optimization is employed to develop a new direct SPT method that can accurately predict the ultimate axial load-bearing capacity of nodular piles. The reliability of the proposed formula is justified by comparing the proportion of end bearing capacity with other published works. It is verified that the developed directed SPT method outperforms all current methods and could be implemented directly in engineering practice.

This study investigates the antiviral efficacy of chitosan‐stabilized silver nanoparticles (AgNPs) against the Foot‐and‐Mouth Disease virus (FMDV), a highly contagious pathogen affecting cloven‐hoofed animals. In vitro experiments demonstrated that AgNPs effectively inhibited FMDV replication in a dose‐dependent manner. At a concentration of 1.56 μg/ml, AgNPs exhibited no cytotoxicity to baby hamster kidney 21 (BHK21) cells while achieving complete deactivation of FMDV at a titer of 103 TCID50 and inhibiting viral growth at a titer of 104 TCID50. These findings suggest the potential of silver nanoparticles as a novel disinfectant for controlling FMDV transmission and preventing disease outbreaks. [ABSTRACT FROM AUTHOR]

Paphiopedilum is among the most popular ornamental orchid genera due to its unique slipper flowers and attractive leaf coloration. Most of the Paphiopedilum species are in critical danger due to over-exploitation. They were listed in Appendix I of the Convention on International Trade in Endangered Species of Wild Fauna and Flora, which prevents their being traded across borders. While most Paphiopedilum species are distinctive, owing to their respective flowers, their vegetative features are more similar and undistinguished. Hence, the conservation of these species is challenging, as most traded specimins are immature and non-flowered. An urgent need exists for effective identification methods to prevent further illegal trading of Paphiopedilum species. DNA barcoding is a rapid and sensitive method for species identification, at any developmental stage, using short DNA sequences. In this study, eight loci, i.e., ITS, LEAFY, ACO, matK, trnL, rpoB, rpoC1, and trnH-psbA, were screened for potential barcode sequences on the Vietnamese Paphiopedilum species. In total, 17 out of 22 Paphiopedilum species were well identified. The studied DNA sequences were deposited to GenBank, in which Paphiopedilum dalatense accessions were introduced for the first time. ACO, LEAFY, and trnH-psbA were limited in amplification rate for Paphiopedilum. ITS was the best single barcode. Single ITS could be used along with nucleotide polymorphism characteristics for species discrimination. The combination of ITS + matK was the most efficient identification barcode for Vietnamese Paphiopedilum species. This barcode also succeeded in recognizing misidentified or wrongly-named traded samples. Different bioinformatics programs and algorithms for establishing phylogenetic trees were also compared in the study to propose quick, simple, and effective tools for practical use. It was proved that both the Bayesian Inference method in the MRBAYES program and the neighbor-joining method in the MEGA software met the criteria. Our study provides a barcoding database of Vietnamese Paphiopedilum which may significantly contribute to the control and conservation of these valuable species.

Motivation: Do financial crises affect everyone equally? Despite the growing concern about income inequality recently, mixed empirical findings have resulted in a long-standing debate about the distribution of income in the aftermath of financial crises. Purpose: The study examines how different types of financial crises affect the distribution of income. Methods and approach: In this study we used a two-step system Generalized method of moments (GMM) model to explore the effects of financial crisis on income inequality. Findings: Any type of financial crisis results in a larger income gap between the rich and the poor. Although little attention has been given to debt and twin and triple crises, they are associated with higher income inequality than banking and currency crises. We also show that the effects of banking crises on income inequality in low-income, lower-middle income and upper-middle income countries (LICs, LMICs and UMICs respectively) are more pronounced than in high-income countries (HICs). Policy implications: Long-and medium-term plans for social assistance programmes in LICS, LMICs and UMICs are needed and should be flexible so that social safety nets can be rapidly adjusted to protect vulnerable groups. Maintaining a high level of fiscal balance during tranquil periods is critical to implementing welfare state expansion policies in times of crisis. Top marginal income and estate taxes should be raised to avoid very high concentrations of income in the aftermath of financial crises. The minimum wage should also be raised to protect low-income workers. [ABSTRACT FROM AUTHOR]

The order of a series of choice tasks presented to respondents in a discrete choice experiment (DCE) could affect the choice outcomes. This study explores the ordering effects in a DCE surveying preferences for improvements in cyclone warning services in Vietnam. Respondents' choices are analysed non-parametrically and parametrically to investigate the ordering effects in their preferences. Across the sequence of six choice questions, the stated demand of respondents is statistically significantly different at the first position from all other positions. Based on a parametric analysis using mixed logit models, we also find that the willingness-to-pay for a number of improvement programs estimated at the first position is relatively larger when compared with the other positions. The findings indicate that although DCEs can provide additional information on respondents' preferences when compared with survey methods using a single valuation question, the trade-off for more information is the ordering effects over a sequence of repeated questions. [ABSTRACT FROM AUTHOR]

Background: MicroRNAs (miRs) are emerging targets for the diagnosis, prognosis and treatment of heart failure (HF). Accumulated evidence showed that microRNA-132 (miR-132) and microRNA-152 (miR-152) play critical roles in the development of multiple pathological processes of the heart. Although their upregulations have been detected in the failing hearts of humans and animal models, little is known about the circulating levels of miR-132 and miR-152 in patients with HF. Methods: Our study was conducted from January 2022 to August 2022 at the Cardiology Department of the University Medical Center in Ho Chi Minh City, Vietnam. During study period, 36 participants were consecutively enrolled, including 18 HF patients and 18 patients who age and sex matched the non-HF controls. Serum samples of study participants were collected on admission and the expression levels of miR-132 and miR-152 were measured by quantitative reverse transcription polymerase chain reaction (RT-PCR). The comparative cycle threshold method (ΔCt) was applied to calculate the relative expression of miRs. Results: The miR concentration in HF group was significantly lower than that in the control group. In contrast, the serum levels of miR-132 and miR-152 were significantly higher in HF patients. Further analyses of receiver operating characteristic (ROC) curve showed that miR-132 and miR-152 individually had moderate diagnostic potential for HF (with area under curve [AUC] values of 0.713 and 0.698, respectively). A positive correlation between these miRs was also confirmed. Conclusion: Serum miR-132 and miR-152 were upregulated in Vietnamese patients with HF and may serve as candidate biomarkers for diagnostic purposes. [ABSTRACT FROM AUTHOR]

This study aims to find the optimized parameters for surveying the milling process of S50C steel in a minimum quantity lubrication (MQL) environment using a support vector machine-genetic algorithm (SVM-GA). Based on the experimental matrix designed by the Taguchi method, surface roughness and cutting force data were collected corresponding to each experiment with changes in input parameters such as cutting speed, tooth feed rate, and axial depth of cut, along with changes in two parameters of the minimum lubrication system: flow rates and injection pressure. Through analysis by the SVR-NSGAII method, the study obtained the optimal parameters of cutting and lubricating conditions when prioritizing either surface roughness or focusing on the cutting force; however, the most comprehensive result is believed to be achieved by balancing these two factors. So, when striving for the neutral value of both output parameters, which are surface roughness (µm) and cutting force (N), the optimum parameters including injection pressure (MPa), flow rates (mL/h), cutting speed (m/min), feed rate (mm/tooth), and axial depth of cut (mm) are proposed.

Light-emitting diodes are increasingly used as artificial light sources in Haematococcus pluvialis cultivation due to the fact of their energy advantages. The immobilized cultivation of H. pluvialis in pilot-scale angled twin-layer porous substrate photobioreactors (TL-PSBRs) was initially performed with a 14/10 h light/dark cycle and showed relatively low biomass growth and astaxanthin accumulation. In this study, the illumination time with red and blue LEDs at a light intensity of 120 µmol photons m−2 s−1 was increased to 16–24 h per day. With a light/dark cycle of 22/2 h, the biomass productivity of the algae was 7.5 g m−2 day−1, 2.4 times higher than in the 14/10 h cycle. The percentage of astaxanthin in the dry biomass was 2%, and the total amount of astaxanthin was 1.7 g m−2. Along with the increase in light duration, adding 10 or 20 mM NaHCO3 to the BG11-H culture medium over ten days of cultivation in angled TL-PSBRs did not increase the total amount of astaxanthin compared with only CO2 addition at a flow rate of 3.6 mg min−1 to the culture medium. Adding NaHCO3 with a 30–80 mM concentration inhibited algal growth and astaxanthin accumulation. However, adding 10–40 mM NaHCO3 caused algal cells to accumulate astaxanthin at a high percentage in dry weight after the first four days in TL-PSBRs.

In this study, samples from 429 dog individuals across three main regions of Vietnam (Southern Vietnam (SVN), Central Vietnam (CVN), and Northern Vietnam (NVN)) were collected to analyze the 582 bp region mtDNA HVI, so as to study the genetic diversity and to screen the rare haplotype E in the Vietnamese village dog population. Nine new haplotypes A, two new haplotypes B, and three haplotypes C were unique to Vietnam dogs, in which the new haplotypes An3, An7, Cn1, and Cn3 concerned mutations at new polymorphism sites (15,517, 15,505, 15,479, and 15,933, respectively) which have not been previously reported. The detection of haplotypes A9 and A29, and the appearance of haplotype A200 in the two individual dogs sampled support that the Southeast Asian dog is the ancestor of today’s Australian dingo and Polynesian dog. The two rare haplotypes E (E1 and E4) were reconfirmed in Vietnamese dogs and discussed. This study also contributes to strengthening the theory of domestication of dogs to the south of the Yangtze River and the Southeast Asian origin of the dingo.

The production of natural astaxanthin is usually accomplished by suspended cultivation of the microalgae Haematococcus pluvialis. In this study, for the purpose of cost reduction, H. pluvialis is grown in pilot scale angled twin-layer porous substrate photobioreactors with light energy from red/blue LEDs that can produce red light, blue light, or a combination of blue-red light. The total dry biomass of the microalgae reached a maximum of 40.74 g.m-2 under blue-red LEDs. The early initiation of blue-red LED illumination (on day 2) after algae immobilization in the biofilm resulted in the highest accumulation of astaxanthin in the dry biomass, which reached a maximum of 1.3% (w/w) after 10 d of culture.

In the production of astaxanthin from Haematococcus pluvialis, the process of growing algal biomass in the vegetative green stage is an indispensable step in both suspended and immobilized cultivations. The green algal biomass is usually cultured in a suspension under a low light intensity. However, for astaxanthin accumulation, the microalgae need to be centrifuged and transferred to a new medium or culture system, a significant difficulty when upscaling astaxanthin production. In this research, a small-scale angled twin-layer porous substrate photobioreactor (TL-PSBR) was used to cultivate green stage biomass of H. pluvialis. Under low light intensities of 20–80 µmol photons m−2·s−1, algae in the biofilm consisted exclusively of non-motile vegetative cells (green palmella cells) after ten days of culturing. The optimal initial biomass density was 6.5 g·m−2, and the dry biomass productivity at a light intensity of 80 µmol photons m−2·s−1 was 6.5 g·m−2·d−1. The green stage biomass of H. pluvialis created in this small-scale angled TL-PSBR can be easily harvested and directly used as the source of material for the inoculation of a pilot-scale TL-PSBR for the production of astaxanthin.