75 research outputs found

    NOISE TRADER RISK: EVIDENCE FROM VIETNAM STOCK MARKET

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    Abstract: This paper investigates the existence of noise trader risk in Vietnam’s stock market and its effect on the daily returns of stock prices. The methodologies contain the estimation of GARCH (1,1) model to filter the residuals using the moving average method to calculate the impact of information traders. Noise trader risk or the risk that is caused by noise traders is derived by subtracting the residuals by the rational traders’ impact. We find that the noise trader risk does exist in Vietnam’s stock market and its impact on daily returns of stocks is unpredictable. Meanwhile, we find a positive impact of information traders on the stock returns. It increases the daily stock returns, and in turn, helps the market to correct itself because the stock prices move back to its fundamental value.Keywords: noise trader risk, GARCH (1,1), Vietnam’s stock marke

    An Assessment of Cough Medicine Dispensing Practice to Children Under Two Years Old in Pharmacies in Ho Chi Minh City Using Simulated-Patient Method

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    Over-the-counter (OTC) cough and cold medications (CCMs) have been used to treat the symptoms of upper respiratory infection in children for decades. The safety of CCMs in children has been questioned. The data on knowledge of pharmacists in supplying cough medicines for children under two years have been limited. This study aimed to evaluate the pharmacists’ dispensing decisions to manage the cough in children under two years old. A descriptive cross-sectional was carried out in 300 pharmacies in 15 districts in Ho Chi Minh City, Vietnam. The pharmacists were interviewed by a simulated patient. The results showed that, information that pharmacists actively asked the client about the patient and disease symptoms was limited. Most pharmacists did not provide adequate instructions and counsel about using drugs for clients. Only 22/300 (7.33%) of pharmacists appropriately provided cough medicines for children under 2 years old. The main reason of inappropriateness was the deficiency of knowledge about updated contraindication of N-acetylcysteine (93.17%). Pharmacists in pharmacies located in districts 3, 11 and Binh Thanh had higher rate of rational provision than those in other districts. A good and full understanding of the patient symptom helped the pharmacists supply cough medicines more reasonably. The limited caution of pharmacists and the low proportion of pharmacists updating contraindication of N-acetylcysteine should be considered as a warning sign in pharmacy practice in Ho Chi Minh City, Vietnam

    Experimental modal analysis and optimal design of cab’s isolation system for a single drum vibratory roller

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    The purpose of this paper is to solve problems about cab’s low-frequency shaking in the direction of forward motion when vibratory roller operates. To solve this problem, a modal test for a single-drum vibratory roller is carried out by the Belgium LMS dynamic testing which is used to identify the model parameters and find out the natural frequency of the vehicle. A Finite Element Analysis (FEA) simulation is carried out to find out the reasons causing the cab’s low-frequency shaking. The model simulation results are found to be in good agreement with the experimental results. Finally, the design parameters of cab’s isolation system are optimized to reach the maximum value of the first-order natural frequency in order to avoid resonance vibration for cab at low frequency and reduce cab’s low-frequency shaking

    Targeted next-generation sequencing on hirschsprung disease: A pilot study exploits DNA pooling

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    To adopt an efficient approach of identifying rare variants possibly related to Hirschsprung disease (HSCR), a pilot study was set up to evaluate the performance of a newly designed protocol for next generation targeted resquencing. In total, 20 Chinese HSCR patients and 20 Chinese sex-matched individuals with no HSCR were included, for which coding sequences (CDS) of 62 genes known to be in signaling pathways relevant to enteric nervous system development were selected for capture and sequencing. Blood DNAs from eight pools of five cases or controls were enriched by PCR-based RainDance technology (RDT) and then sequenced on a 454 FLX platform. As technical validation, five patients from case Pool-3 were also independently enriched by RDT, indexed with barcode and sequenced with sufficient coverage. Assessment for CDS single nucleotide variants showed DNA pooling performed well (specificity/sensitivity at 98.4%/83.7%) at the common variant level; but relatively worse (specificity/sensitivity at 65.5%/61.3%) at the rare variant level. Further Sanger sequencing only validated five out of 12 rare damaging variants likely involved in HSCR. Hence more improvement at variant detection and sequencing technology is needed to realize the potential of DNA pooling for large-scale resequencing projects. © 2014 John Wiley & Sons Ltd/University College London.postprin

    Study on active tectonic faults using soil radon gas method in Viet Nam

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    This paper presents the results of soil radon gas measurement in three areas, including Thac Ba and Song Tranh 2 hydropower plants, and the planned locations of the nuclear power plants Ninh Thuan 12 using solid-state nuclear track detectors (SSNTD) with the aim of clarifying the activity of tectonic faults in these areas. The activity of tectonic faults was assessed through radon activity index KRn (the ratio between anomaly and threshold), which was divided into 5 levels as follows ultra-high (KRn 10), high (10≥KRn 5), high (5≥KRn 3), medium (3≥KRn 2) and low (KRn≤2). Soil radon gas measurement results showed that in the radon gas concentrations in the Thac Ba hydropower plant area ranged from 72 Bq/m3 to 273.133 Bq/m3 and maximum radon activity index KRn reached 9.75 (high level). High KRn indexes show Chay River fault active in recent time and the sub-meridian distribution of Rn anomalies suggested a right-slip motion of the fault. Rn concentrations in the Ninh Thuan 12 areas ranged from 6 Bq/m3 to 52.627 Bq/m3, however, the KRn indexes were mostly low (KRn≤3) and the highest value was only 3.42, suggesting that expression of activity of the tectonic faults in this region is not clear, even no expression of fault activity. In the Song Tranh 2 hydropower plant and adjacent areas, radon concentrations ranged from 29 Bq/m3 to 77.729 Bq/m3 and maximum KRn index was 20.16 (ultra-high level). The faults having clearer activity expression are Hung Nhuong - Ta Vy, Song Tra Bong and some high order faults, especially the northwest - southeast segments of these faults or their intersections with the northwest - southeast faults. In addition, the high values KRn in the mentioned intersections can be evidenced for the activeness of northwest - southeast faults at the present time. The studies on active faults using soil radon gas method were performed in areas with very different geological and structural features, but the results are well consistent with the results of previous investigations obtained by other methods. It confirmed the effectiveness and capability of soil radon gas geochemistry applying to study active tectonic faults.ReferencesAl-Hilal M., Al-Ali A., 2010. The role of soil gas radon survey in exploring unknown subsurface faults at Afamia B dam, Syria. Radiat. Meas, 45, 219-224.Amponsah,   P.,   Banoeng-Yakubo,   B.,   Andam,   A., Asiedu, D.,  2008. Soil  radon  concentration along fault systems in parts of south eastern Ghana. J. Afr. Earth Sci. 51, 39-48.Asumadu-Sakyi A.B., Fletcher J.J., Oppon O.C., Qua- shie F.K., Wordson D.A., Adjei C.A., Amartey E.O., Darko E.O. and Amponsah P.,  2011. Preliminary Studies on Geological Fault Location Using Solid State Nuclear Track Detection. 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    CHẾ TẠO VÀ TÍNH CHẤT CỦA VẬT LIỆU TỔ HỢP GRAPHENE – ỐNG NANO CÁCBON – HẠT NANO VÀNG

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    In this work, a composite nanomaterial consisting of graphene (Gr), double-wall carbon nanotube (DWCNTs) and gold nanoparticles (AuNPs), designated as DWCNTs-AuNPs-Gr was synthesized via the thermal chemical vapour deposition technique. The morphology and electrical and electrochemical properties of the material were characteried by using field emission scanning electron microscopy, Raman spectroscopy, four-probe sheet resistance measurement, and cyclic voltammetry (CV). The average sheet resistance value of DWCNTs-AuNPs-Gr is 549 W/sq, 2.3 times lower than that of graphene. The current response of a DWCNTs-AuNPs-Gr-modified electrode in a 2 mM K3[Fe(CN)6]/K4[Fe(CN)6] solution with 0.1 M PBS is 15.79 µA, 1.48 times higher than that of a graphene-modified electrode and 2.57 times higher than that of a bare electrode. The DWCNTs-AuNPs-Gr material can be used for electrochemical biosensors to detect various bioelements.Trong công trình này, màng tổ hợp của vật liệu graphene (Gr) – ống nano cácbon hai tường (DWCNT) và hạt nano kim loại vàng (AuNPs) (DWCNT-AuNPs-Gr) đã được chế tạo bằng phương pháp lắng đọng pha hơi nhiệt hóa học (CVD). Hình thái học bề mặt và các tính chất điện, điện hóa của vật liệu tổ hợp đã được khảo sát thông qua kính hiển vi điện tử quét phát xạ trường, phổ Raman, điện trở bốn mũi dò và kỹ thuật quét thế vòng (CV). Với nồng độ DWCNTs 0,3 g/L và tốc độ quay phủ 4000 vòng/phút, vật liệu DWCNTs-AuNPs-Gr có điện trở bề mặt giảm 2,3 lần so với màng Gr và đạt khoảng 549 W/sq; dòng đỉnh đáp ứng trong dung dịch 2 mM K3[Fe(CN)6]/K4[Fe(CN)6] trong 0,1 M PBS đạt 15,79 µA tại 50 mV/s, cao gấp 1,48 lần so với điện cực biến tính màng Gr và gấp 2,57 lần so với điện cực trần. Vật liệu DWCNTs-AuNPs-Gr có tiềm năng ứng dụng trong cảm biến điện hóa để phát hiện các phần tử sinh học khác nhau

    Bringing social and cultural considerations into environmental management for vulnerable coastal communities: Responses to environmental change in Xuan Thuy National Park, Nam Dinh Province, Vietnam

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    This paper elaborates the importance of considering social and cultural factors within management responses to environmental change in coastal areas. The case study taken is Xuan Thuy National Park in Nam Dinh Province, Vietnam. This is a marginalised coastal area where rising sea levels, increasing storm surges and saltwater intrusion place pressure on coastal ecosystems, yet where communities continue to rely on these same ecosystems for agriculture- and aquaculture-related livelihoods. We interview stakeholders in Xuan Thuy National Park, connecting these with a narrative review of existing research into social and environmental change in the park to understand research gaps and challenges for vulnerable coastal areas like the Nam Dinh coast. Based on our findings, we suggest that whilst the effects of a changing environment on physical health and economic activity are increasingly well understood, effects on wellbeing and social relations can be even more immediate and profound in daily living. In turn, we argue environmental management has a crucial role to play not only for ecosystem-based adaptation, but also in sustaining wellbeing and allowing culturally meaningful practices to continue – especially in coastal regions where changes can be even more intense and immediate. However, we caution that whilst techno-scientific solutions grounded in environmental management do have significant potential in reducing impacts of extreme events and slower-onset environmental changes, they must not divert attention away from structural issues that can make some people or areas more vulnerable in the first instance

    Improvement in neoantigen prediction via integration of RNA sequencing data for variant calling

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    IntroductionNeoantigen-based immunotherapy has emerged as a promising strategy for improving the life expectancy of cancer patients. This therapeutic approach heavily relies on accurate identification of cancer mutations using DNA sequencing (DNAseq) data. However, current workflows tend to provide a large number of neoantigen candidates, of which only a limited number elicit efficient and immunogenic T-cell responses suitable for downstream clinical evaluation. To overcome this limitation and increase the number of high-quality immunogenic neoantigens, we propose integrating RNA sequencing (RNAseq) data into the mutation identification step in the neoantigen prediction workflow.MethodsIn this study, we characterize the mutation profiles identified from DNAseq and/or RNAseq data in tumor tissues of 25 patients with colorectal cancer (CRC). Immunogenicity was then validated by ELISpot assay using long synthesis peptides (sLP).ResultsWe detected only 22.4% of variants shared between the two methods. In contrast, RNAseq-derived variants displayed unique features of affinity and immunogenicity. We further established that neoantigen candidates identified by RNAseq data significantly increased the number of highly immunogenic neoantigens (confirmed by ELISpot) that would otherwise be overlooked if relying solely on DNAseq data.DiscussionThis integrative approach holds great potential for improving the selection of neoantigens for personalized cancer immunotherapy, ultimately leading to enhanced treatment outcomes and improved survival rates for cancer patients
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