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Text-To-Speech (TTS) was one of nine shared tasks in the eighth annual international VLSP 2021 workshop. All three previous TTS shared tasks were conducted on reading datasets. However, the synthetic voices were not natural enough for... more
Text-To-Speech (TTS) was one of nine shared tasks in the eighth annual international VLSP 2021 workshop. All three previous TTS shared tasks were conducted on reading datasets. However, the synthetic voices were not natural enough for spoken dialog systems where the computer must talk to the human in a conversation. Speech datasets recorded in a spontaneous environment help a TTS system to produce more natural voices in speaking style, speaking rate, intonation... Therefore, in this shared task, participants were asked to build a TTS system from a spontaneous speech dataset. This 7.5-hour dataset was collected from a channel of a famous youtuber "Giang ơi..."and then pre-processed to build utterances and their corresponding texts. Main challenges at this task this year were: (i) inconsistency in speaking rate, intensity, stress and prosody across the dataset, (ii) background noises or mixed with other voices, and (iii) inaccurate transcripts. A total of 43 teams registered...
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The VLSP 2021 is the eighth annual international workshop whose campaign was organized at the University of Information Technology, Vietnam National University, Ho Chi Minh City (UIT-VNU-HCM). This was the first time we organized the... more
The VLSP 2021 is the eighth annual international workshop whose campaign was organized at the University of Information Technology, Vietnam National University, Ho Chi Minh City (UIT-VNU-HCM). This was the first time we organized the Speaker Verification shared task with two subtasks SV-T1 and SV-T2. SV-T1 focuses on the development of SV models with limited data, and SV-T2 focuses on testing the capability and the robustness of SV systems. With the aim to boost the development of robust models, we collected, processed, and published a speaker dataset in noisy environments containing 50 hours of speech and more than 1,300 speaker identities. A total of 39 teams registered to participate in this shared task, 15 teams received the dataset, and finally, 7 teams submitted final solutions. The best solution leveraged English pre-trained models and achieved 1.755% and 1.950% Equal Error Rate for SV-T1 and SV-T2 respectively.
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Automatic speech recognition (ASR) is gaining huge advances with the arrival of End-to-End architectures. Semi-supervised learning methods, which can utilize unlabeled data, have largely contributed to the success of ASR systems, giving... more
Automatic speech recognition (ASR) is gaining huge advances with the arrival of End-to-End architectures. Semi-supervised learning methods, which can utilize unlabeled data, have largely contributed to the success of ASR systems, giving them the ability to surpass human performance. However, most of the researches focus on developing these techniques for English speech recognition, which raises concern about their performance in other languages, especially in low-resource scenarios. In this paper, we aim at proposing a Vietnamese ASR system for participating in the VLSP 2021 Automatic Speech Recognition Shared Task. The system is based on the Wav2vec 2.0 framework, along with the application of self-training and several data augmentation techniques. Experimental results show that on the ASR-T1 test set of the shared task, our proposed model achieved a remarkable result, ranked as the second place with a Syllable Error Rate (SyER) of 11.08%.
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Engineering design process is one of the problem – solving approachs used in STEM education. Students can engage in the practices of the engineering field through solving problems using the engineering design process. Based on literature... more
Engineering design process is one of the problem – solving approachs used in STEM education. Students can engage in the practices of the engineering field through solving problems using the engineering design process. Based on literature reviews on Engineering design process as well as fabricating water filter system, this study presents 36 tenth-grade students of high school in Vietnam completed an engineering-based problem on filtering water involving integrated STEM learning. Students employed five – step engineering design processes and STEM disciplinary knowledge to plan, sketch, construct, evaluate and redesign water filter systems taken from public fountains, tap water, river water, sea water, and water contaminated with alum.
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The paper aims to assess the changes of the streamflow under the impact of irrigation constructions in La Nga river basin using the Long and Short term runoff (LST) model. The LST model was calibrated and validated for the period of... more
The paper aims to assess the changes of the streamflow under the impact of irrigation constructions in La Nga river basin using the Long and Short term runoff (LST) model. The LST model was calibrated and validated for the period of 1987–1995 and 1996–1999, respectively, to simulate the natural streamflow for the post–construction phase. Statistical metrics, including R2 coefficients, efficiency coefficients (NSE), percent error (PBIAS) and standard monitoring deviation ratio (RSR) were used to evaluate the model performance. The results showed that, LST model performed well in the flow simulation by the high values of R2 and NSE index greater than 0.80, RSR smaller than 0.50 and PBIAS lower than 7.22%. The comparison between the simulated (natural) and observed flows illustrated that there were changes of the flow regime in the post–construction phase. The average seasonal flow decreases 24.59% and increased 12.06% in the wet and dry season, respectively at Phu Dien station. Meanwh...
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The Coronavirus disease-2019 (COVID-19) pandemic caused by the Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2), has become a dire global health concern. The development of vaccines with high immunogenicity and safety is... more
The Coronavirus disease-2019 (COVID-19) pandemic caused by the Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2), has become a dire global health concern. The development of vaccines with high immunogenicity and safety is crucial for control of the global COVID-19 pandemic and prevention of further illness and fatalities. Here, we report development of SARS-CoV-2 vaccine candidate, Nanocovax, based on recombinant protein production of the extracellular (soluble) portion of the S protein of SARS-CoV-2. The results showed that Nanocovax induced high levels of S protein-specific IgG, as well neutralizing antibody in three animal models including Balb/C mice, Syrian hamsters, and non-human primate (Macaca leonina). In addition, the viral challenge study using the hamster model showed that Nanocovax protected the upper respiratory tract from SARS-CoV-2 infection. No adverse effects were induced by Nanocovax in swiss mice (Musmusculus var. Albino), Rats (Rattus norvegicus), and...
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Tourism development policy will pay attention to stakeholders, especially the people, who play an important role. However, in reality, when people participate in rural tourism development, they are not equipped with basic knowledge and... more
Tourism development policy will pay attention to stakeholders, especially the people, who play an important role. However, in reality, when people participate in rural tourism development, they are not equipped with basic knowledge and skills in managing and serving tourists. Because the benefits between stakeholders are still not clear, the participation of people in rural tourism development is currently only passive. Active participation need to be directed from the Government and local authorities because the concept that rural tourism development is not only about creating economic benefits but also associated with conservation and preservation, together with keeping and promoting cultural - historical values in rural areas.
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User satisfaction with information system quality has long been a substantial topic in the literature of information system (IS). Based on the key constructs of IS success model (including system quality and information quality) and... more
User satisfaction with information system quality has long been a substantial topic in the literature of information system (IS). Based on the key constructs of IS success model (including system quality and information quality) and technology acceptance model (including perceived ease of use and perceived usefulness), this paper builds and validates a theoretical framework to explain user satisfaction with information system quality. A survey study with AMOS-SEM analysis of 363 users of management information systems in 9 hospitals in HCMC, Vietnam showed that 12 of 14 hypotheses were empirically supported. The findings affirmed the direct influence of system quality, information quality and top management support on perceived ease of use, perceived usefulness and trust, and then on user satisfaction. The results also reinforced the impact of perceived ease of use on perceived usefulness, and the joint influence of perceived usefulness and trust on user satisfaction. The paper is a...
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Migration is an indispensable trend in Ho Chi Minh City (HCMC), and immigrant workers have become an important resource contributing to economic growth. This study aims to clarify the quality of life of immigrant workers and offer a... more
Migration is an indispensable trend in Ho Chi Minh City (HCMC), and immigrant workers have become an important resource contributing to economic growth. This study aims to clarify the quality of life of immigrant workers and offer a scientific basis for policies that promote the positive contributions of immigrant workers. A linear structural equation model is used to analyze data of 394 observations, including 253 migrant workers and 141 local workers. Quality of life is first assessed by whether immigrant workers can meet or satisfy a variety of their needs. Then the relationship between the needs and outcomes such as income, education, and effort-to-stay is analyzed using a mediator named assimilation. Finally, a comparison between groups such as migrant and local workers, migrants living in HCMC under and over ten years is conducted. The results indicated that employment, settlement, and social support have a direct impact on their assimilation and the strongest indirect impact ...
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Poly(lactic acid)/chitosan (PLA/CS) green nanoparticles containing hydroquinine (Hq) were prepared by emulsion method. The content of Hq was 10–50 wt% compared with the weight total of PLA and CS. The characteristics of these... more
Poly(lactic acid)/chitosan (PLA/CS) green nanoparticles containing hydroquinine (Hq) were prepared by emulsion method. The content of Hq was 10–50 wt% compared with the weight total of PLA and CS. The characteristics of these nanoparticles were analyzed by Fourier transform infrared (FTIR), differential scanning calorimetry, field emission scanning electron microscopy (FESEM), and particle size analysis. The wavenumbers of C=O, C=N, OH, and CH3 groups in FTIR spectra of the PLA/CS/Hq (PCHq) nanoparticles shifted in comparision with neat PLA, CS, and Hq that proved the interaction between these components. The FESEM images and particle size analysis results showed that the basic particle size of PCHq nanoparticles ranged between 100 and 200 nm. The Hq released from PLA/CS nanoparticles in pH 2 and pH 7.4 solutions was determined by ultraviolet-visible method. The obtained results indicated that the linear regression coefficient of calibration equation of Hq in the above solutions app...
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In this study, akageneite/graphene oxide (β-FeOOH/GO) nanocomposite was fabricated by in situ forced hydrolysis of iron (III) chloride. The structure and morphology of β-FeOOH/GO were characterized by Fourier Transform Infrared... more
In this study, akageneite/graphene oxide (β-FeOOH/GO) nanocomposite was fabricated by in situ forced hydrolysis of iron (III) chloride. The structure and morphology of β-FeOOH/GO were characterized by Fourier Transform Infrared Spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), and Brunauer–Emmett– Teller (BET) specific surface area. XRD, FTIR, and TEM results indicated that β-FeOOH nanoparticles were successfully decorated on the surface of GO nanosheets. The BET specific surface area of β-FeOOH/GO was observed of 97.94 m2/g. The nanocomposite was used as an adsorbent for removal of arsenic (As5+) from water. Adsorption experiments were carried out to investigate contact time, pH values, and As5+ initial concentrations. The adsorption equilibrium time was reached within 180 minutes. The adsorption was well-fitted by a pseudo-second-order kinetic and Langmuir isotherm model. The maximum adsorption capacity of β-FeOOH/GO for As5+ ions of 94.34 mg/g that was calculated from the Langmuir model at pH 3. Accordingly, the nanocomposite β-FeOOH/GO could be considered as a highly efficient adsorbent for removing arsenic from water.
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Low-molecular-weight compounds with anticoagulant activity were isolated from the scorpion Heterometrus laoticus venom. The determination of the structure of the isolated compounds by nuclear magnetic resonance and mass spectrometry... more
Low-molecular-weight compounds with anticoagulant activity were isolated from the scorpion Heterometrus laoticus venom. The determination of the structure of the isolated compounds by nuclear magnetic resonance and mass spectrometry showed that one of the isolated compounds is adenosine, and the other two are dipeptides leucyl-tryptophan and isoleucyl-tryptophan. The anticoagulant properties of adenosine, which is an inhibitor of platelet aggregation, is well known, but its presence in scorpion venom is shown for the first time. The ability of leucyl-tryptophan and isoleucyl-tryptophan to slow down blood clotting and their presence in scorpion venom are also established for the first time.
Research Interests: Chemistry, Medicine, Mice, Animals, Venom, and 5 moreSCORPIONS, Anticoagulants, Tryptophan, Scorpion, and Molecular weight
Assessment of the climate and land-use change impacts on the hydrology and water quality of a river basin is important for the development and management of water resources in the future. The objective of this study was to examine the... more
Assessment of the climate and land-use change impacts on the hydrology and water quality of a river basin is important for the development and management of water resources in the future. The objective of this study was to examine the impact of climate and land-use change on the hydrological regime and nutrient yield from the 3S River Basin (Sekong, Srepok, and Sesan) into the 3S River system in Southeast Asia. The 3S Rivers are important tributaries of the Lower Mekong River, accounting for 16% of its annual flow. This transboundary basin supports the livelihoods of nearly 3.5 million people in the countries of Laos, Vietnam, and Cambodia. To reach a better understanding of the process and fate of pollution (nutrient yield) as well as the hydrological regime, the Soil and Water Assessment Tool (SWAT) was used to simulate water quality and discharge in the 3S River Basin. Future scenarios were developed for three future periods: 2030s (2015-2039), 2060s (2045-2069), and 2090s (2075-...
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In response to the prominence of English language education in Viet Nam, the Ministry of Education and Training (MOET) has developed policies to introduce English into schools. The recent MOET decisions and guidelines in which English is... more
In response to the prominence of English language education in Viet Nam, the Ministry of Education and Training (MOET) has developed policies to introduce English into schools. The recent MOET decisions and guidelines in which English is taught as a compulsory subject from Grade 3 have raised many issues related to their effectiveness. However, there is limited research on whether the implementation of these policies has been successful in the diversity of Vietnamese school contexts and most notably in rural settings. This paper provides a brief overview of the English language education policies in Viet Nam and issues associated with their implementation, with Kaplan and Baldauf’s (2005) planning goals providing the framework for discussion. The focus then shifts to issues of implementation currently being experienced in a Vietnamese province drawing on a study using a mixed methodology approach. Questionnaires from 111 primary school leaders and English teachers in 64 primary scho...
Looking for the possibility of using Refused Derived Fuels (RDF) in the substitution of fossil fuels is one of the main subjects in the Waste to Energy aspect. Therefore this study has been taken in this direction. The influence of waste... more
Looking for the possibility of using Refused Derived Fuels (RDF) in the substitution of fossil fuels is one of the main subjects in the Waste to Energy aspect. Therefore this study has been taken in this direction. The influence of waste composition on RDF quality produced by Dry Stabilization Process (DSP) and the evaluation of CO2 emission of this product were undertaken.
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Background: Extended-spectrum β-lactamases (ESBLs) are enzymes capable of hydrolyzing oxyimino-β-lactams and inducing resistance to third generation cephalosporins. The genes encoding ESBLs are widespread and generally located on highly... more
Background: Extended-spectrum β-lactamases (ESBLs) are enzymes capable of hydrolyzing oxyimino-β-lactams and inducing resistance to third generation cephalosporins. The genes encoding ESBLs are widespread and generally located on highly transmissible resistance plasmids. We aimed to investigate the complement of ESBL genes in E. coli and Klebsiella pneumoniae causing nosocomial infections in hospitals in Ho Chi Minh City, Vietnam. Methodology: Thirty-two non-duplicate isolates of E. coli and Klebsiella pneumoniae causing nosocomial infections, isolated between March and June 2010, were subjected to antimicrobial susceptibility testing. All isolates were PCR-amplified to detect the blaSHV, blaTEM and blaCTX-M ESBL genes and subjected to plasmid analysis. Results: We found that co-resistance to multiple antimicrobials was highly prevalent, and we report the predominance of the blaCTX-M-15 and blaCTX-M-27 genes, located on highly transmissible plasmids ranging from 50 to 170 kb in size...
Research Interests: Microbiology, Biology, Developing Countries, Vietnam, Medicine, and 14 moreAntibiotic Resistance, Humans, Escherichia coli, Polymerase Chain Reaction, Plasmids, Antimicrobial, Anti-Bacterial Agents, Microbial Sensitivity Tests, Plasmid, Escherichia Coli Infections, Beta Lactamases, Klebsiella pneumoniae, beta-Lactam Resistance, and Cross Infection
Paper production can be considered as an important factor for the development of one country. On the way of development, Vietnam has increased steadily in paper consumption; however, the paper production did not get to the same speed. One... more
Paper production can be considered as an important factor for the development of one country. On the way of development, Vietnam has increased steadily in paper consumption; however, the paper production did not get to the same speed. One of the reasons remains in input material which composes of wood or other agricultural fiber sources and recovered paper. Statistical data on pulp and paper production have been taken into consideration. Reasons for the low in recycling rate have been analyzed.
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In an earlier version of the approximate mean value theorem, Loewen [2] established the theorem for the Fréchet subgradients in Banach space whose norm is Fréchet smooth. Observe that a Banach space whose norm is Fréchet smooth is an... more
In an earlier version of the approximate mean value theorem, Loewen [2] established the theorem for the Fréchet subgradients in Banach space whose norm is Fréchet smooth. Observe that a Banach space whose norm is Fréchet smooth is an Asplund space but the inverse is not ...
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Drug resistance is a major hurdle to the success of chemotherapy. The permeability glycoprotein (P-gp) is an important factor dictating drug access to the cells, as it controls the efflux of chemotherapeutic agents against the... more
Drug resistance is a major hurdle to the success of chemotherapy. The permeability glycoprotein (P-gp) is an important factor dictating drug access to the cells, as it controls the efflux of chemotherapeutic agents against the concentration gradient. Pmd1, a P-gp-like protein, was recently isolated as a doxorubicin resistance gene in fission yeast. Although the null mutant of pmd1 (Δpmd1) exhibited sensitivity to doxorubicin, it showed an unexpectedly high resistance to the drug at relatively high concentrations. The data presented here suggest that this is due to the presence of cooperative processes that can complement and counteract drug cytotoxicity in the absence of Pmd1. One such factor, Rav1, is an essential factor in controlling the assembly of the pH-regulating transporter vacuolar-ATPase (V-ATPase) in fission yeast. The simultaneous disruption of Pmd1 and Rav1 resulted in a prominent accumulation of doxorubicin in the cytoplasm of cells, accompanied by a decline in cell viability. With concurrent treatment of pharmacological inhibitors in human cervical cancer cells, P-gp and V-ATPase were further shown to act synergistically to sensitize cells to doxorubicin also in the human cells. Furthermore, a novel Cornichon-like protein SPAC2C4.05 (herein named as Cor1) was demonstrated for the first time to be involved in the interaction with P-gp and V-ATPase to counteract doxorubicin-dependent cytotoxicity. Therefore this study identified a molecular cooperation between multiple membrane transporter proteins that confers chemoresistance to cells against the chemical insult of doxorubicin. Interestingly, this network exhibited differential effects to doxorubicin as compared with its close epimeric analog epirubicin, suggestive of the intricacy of the drug response regulated by this synergistic interaction. A model is discussed on how the versatility of this network can differentiate closely related chemical drug structures yet allow for the robustness to counteract a vast range of drugs.