177 research outputs found
Factors influencing the willingness-to-pay of internet users in Vietnam for the fee-based online contents
The aim of this study is to identify key factors that influence the willingness-to-pay (WTP) of Internet users in Vietnam for fee-based online contents. The study collects 309 suitable questionnaires filled by internet users over 18 years old and living in Vietnam, who frequently use online contents and have ideally made payment for online contents. The analysis results indicate that the willingness-to-pay for the fee-based online contents of Vietnamese users are influenced by their attitudes toward paying and ethical self-efficacy for online piracy. The study also identifies the antecedents of attitude, which include the perceived benefits of usefulness and enjoyment, the perceived sacrifice of the fee, social influences from other people, and especially the free mentality. The study then suggests managerial implications to online content providers in enhancing WTP for the fee-based online contents in Vietnam
Datasets of land use change and flood dynamics in the vietnamese mekong delta
This paper compiles the data associated with a research article published in STOTEN [1]. The data set represents figures, tables, and images illustrating the temporal and spatial distribution of land use and flood dynamics from 2000 to 2020 in the Vietnamese Mekong Delta (VMD). The MODIS imageries were freely accessed online via the NASA website [2] and processed to land use and flood maps based on the algorithms by Sakamoto et al. [3,4]. The MODIS products show a high validation with statistical data and radar satellites [1]. The datasets of flood map and land use, therefore, are available to scientists, engineers, and policy-makers in agricultural management associated with flood management in the VMD. They could be used for policy settings, household livelihood assessment as well as other economic analyses for the VMD region due to the change of land use and flooding dynamics
The influence of hardware impairment on the system performance of two-way relaying network
In this research, the system performance of the half-duplex two-way relay network under hardware impairment condition is presented and investigated. In this system model, the time switching protocol and amplify-and-forward (AF)-based are considered. First, of all, the analytical expressions of the outage probability, and achievable throughput with the exact closed form and asymptotic form were proposed and derived. Furthermore, the research results are derived and convinced by Monte-Carlo calculation. The numerical results demonstrated and convinced the analytical and the simulation results are agreed for all possible system parameters
SCREENING ANTIBACTERIAL ACTIVITY OF VIETNAMESE PLANT EXTRACTS AGAINST HUMAN PATHOGENIC BACTERIA
Objectives: Infectious diseases caused by bacteria are a leading cause of death worldwide. Hence, the objectives of the study are aimed to evaluate the antibacterial activity against five human pathogenic bacteria of methanolic extracts from 66 plants collected from Vietnam.
Methods: The broth microdilution method was used to determine the minimum inhibitory concentration (MIC) of methanol extracts of 66 plant species against five bacterial strains.
Results: In this study, all the plant extracts were active against at least one train with MIC values ranging from 24 to 2048 μg/mL. Twenty-five plant extracts were active against all three Gram-positive bacteria (Bacillus cereus, Bacillus subtilis, and Staphylococcus aureus). Of these, the extracts of Macaranga trichocarpa (Rchb. f. and Zoll.) Mull. Arg. (Euphorbiaceae), Calophyllum inophyllum L. (Clusiaceae) and Caryodaphnopsis baviensis (Lecomte) Airy Shaw (Lauraceae) exhibited the highest antibacterial activity (MIC =24–128 μg/mL), followed by extracts of Betula alnoides Buch.- Ham. e × . D. Don (Betulaceae), Acronychia pedunculata (L.) Miq. (Rutaceae), Croton alpinus A. Chev. ex Gagnep. (Euphorbiaceae) (MIC =64–256 μg/mL). Furthermore, the extract of Rhus chinensis Mill. (Anacardiaceae) and Annona reticulata L. (Annonaceae) exhibited potent antibacterial activity against the two Bacillus species (MIC =32–64 μg/mL).
Conclusion: Results of this study reveal that plant extracts from Vietnam have highly antibacterial activity against Gram-positive bacteria. These results suggest that Vietnamese plant extracts may be a rich source of antibacterial drugs
Gauge Bosons in the 3-3-1 Model with Three Neutrino Singlets
We show that the mass matrix of electrically neutral gauge bosons in the recent proposed  model based on group with three neutrino singlets [9] has two exact eigenvalues and corresponding eigenvectors. Hence the neutral non-Hermitian gauge boson is properly determined.With extra vacuum expectation values of the Higgs fields, there are mixings among charged gauge bosons and as well as amongneutral gauge bosons and . From the boson decay width, we get lower bound on  scale of the model about few TeVs
Perforator Mapping of the Superficial and Deep Inferior Epigastric Artery in the Abdominal Region of the Vietnamese
BACKGROUND: Previous studies worldwide have investigated the anatomy of the perforators of the deep inferior epigastric arteries to figure out the navigation patterns of the perforators on the abdominal wall. This has been inconsistent amongst the researchers about how to select the perforator to increase the blood supply area for the flap.
AIM: To explore the blood supply area of the perforators of the superficial and deep inferior epigastric artery in the abdominal region of the Vietnamese by dissection and 64-slice multislice computed tomography (64-slice MSCT).
METHODS: A descriptive cross-sectional study Center from September 2014 to September 2016 on two groups including 30 cadavers fixed by formalin 10% in Anatomy Department of UPNT, and 37 patients getting the 64-slice MSCT abdominal arteries angiogram.
RESULTS: The superficial epigastric arteries at the level of the inguinal ligament were located in the middle region, with 96% (right) and 88.5% (left). The anterior superior iliac spine level was in the middle, and lateral regions of 68% and 32% respectively. The level of the umbilical cord was in the lateral region with 66.7% and 85.7%, respectively. There were about 6 perforators of the deep inferior epigastric arteries located in the navel area. These perforators were 70% in the medial region and 30% in the middle region.
CONCLUSION: Mapping the blood supply based on the fourth space in the abdominal region in which the superfical inferior epigastric arteries supplied the lateral area. The middle and the internal ones were the perforators of the deep inferior epigastric arteries
Investigation of Sodium Manganese Oxide Nanowires Synthesized by Hydrothermal Method for Alkaline Ion Battery
Sodium Manganese Oxide (NaxMnO2) has attracted much attention as cathode materials for alkaline ion battery due to the ability of fast charge and discharge ion Na+, in particular in nanoscale. We report on the synthesis of NaxMnO2 nanowires via hydrothermal synthesis route from Mn2O3 and NaOH solution. The morphological observation indicates that the obtained Na0.44MnO2 nanowires with diameters of about 20-30 nm, length up to several micrometers were formed by this process. The electrochemical properties of fabricated materials were investigated by means of cyclic voltammetry technique and show that Sodium Manganese Oxide (NaxMnO2) is a promising material in the field of research and fabrication alkaline ion battery
Point-of-care C-reactive protein testing to reduce inappropriate use of antibiotics for non-severe acute respiratory infections in Vietnamese primary health care: a randomised controlled trial
Background Inappropriate antibiotic use for acute respiratory tract infections is common in primary health care, but
distinguishing serious from self-limiting infections is diffi cult, particularly in low-resource settings. We assessed
whether C-reactive protein point-of-care testing can safely reduce antibiotic use in patients with non-severe acute
respiratory tract infections in Vietnam.
Method We did a multicentre open-label randomised controlled trial in ten primary health-care centres in northern
Vietnam. Patients aged 1–65 years with at least one focal and one systemic symptom of acute respiratory tract infection
were assigned 1:1 to receive either C-reactive protein point-of-care testing or routine care, following which antibiotic
prescribing decisions were made. Patients with severe acute respiratory tract infection were excluded. Enrolled
patients were reassessed on day 3, 4, or 5, and on day 14 a structured telephone interview was done blind to the
intervention. Randomised assignments were concealed from prescribers and patients but not masked as the test
result was used to assist treatment decisions. The primary outcome was antibiotic use within 14 days of follow-up. All
analyses were prespecifi ed in the protocol and the statistical analysis plan. All analyses were done on the intention-totreat
population and the analysis of the primary endpoint was repeated in the per-protocol population. This trial is
registered under number NCT01918579.
Findings Between March 17, 2014, and July 3, 2015, 2037 patients (1028 children and 1009 adults) were enrolled and
randomised. One adult patient withdrew immediately after randomisation. 1017 patients were assigned to receive
C-reactive protein point-of-care testing, and 1019 patients were assigned to receive routine care. 115 patients in the
C-reactive protein point-of-care group and 72 patients in the routine care group were excluded in the intention-to-treat
analysis due to missing primary endpoint. The number of patients who used antibiotics within 14 days was 581 (64%)
of 902 patients in the C-reactive protein group versus 738 (78%) of 947 patients in the control group (odds ratio
[OR] 0·49, 95% CI 0·40–0·61; p<0·0001). Highly signifi cant diff erences were seen in both children and adults, with
substantial heterogeneity of the intervention eff ect across the 10 sites (I²=84%, 95% CI 66–96). 140 patients in the
C-reactive protein group and 137 patients in the routine care group missed the urine test on day 3, 4, or 5. Antibiotic
activity in urine on day 3, 4, or 5 was found in 267 (30%) of 877 patients in the C-reactive protein group versus
314 (36%) of 882 patients in the routine treatment group (OR 0·78, 95% CI 0·63–0·95; p=0·015). Time to resolution
of symptoms was similar in both groups. Adverse events were rare, with no deaths and a total of 14 hospital admissions
(six in the C-reactive protein group and eight in the control group).
Interpretation C-reactive protein point-of-care testing reduced antibiotic use for non-severe acute respiratory tract
infection without compromising patients’ recovery in primary health care in Vietnam. Health-care providers might
have become familiar with the clinical picture of low C-reactive protein, leading to reduction in antibiotic prescribing
in both groups, but this would have led to a reduction in observed eff ect, rather than overestimation. Qualitative
analysis is needed to address diff erences in context in order to implement this strategy to improve rational antibiotic
use for patients with acute respiratory infection in low-income and middle-income countries
TextANIMAR: Text-based 3D Animal Fine-Grained Retrieval
3D object retrieval is an important yet challenging task, which has drawn
more and more attention in recent years. While existing approaches have made
strides in addressing this issue, they are often limited to restricted settings
such as image and sketch queries, which are often unfriendly interactions for
common users. In order to overcome these limitations, this paper presents a
novel SHREC challenge track focusing on text-based fine-grained retrieval of 3D
animal models. Unlike previous SHREC challenge tracks, the proposed task is
considerably more challenging, requiring participants to develop innovative
approaches to tackle the problem of text-based retrieval. Despite the increased
difficulty, we believe that this task has the potential to drive useful
applications in practice and facilitate more intuitive interactions with 3D
objects. Five groups participated in our competition, submitting a total of 114
runs. While the results obtained in our competition are satisfactory, we note
that the challenges presented by this task are far from being fully solved. As
such, we provide insights into potential areas for future research and
improvements. We believe that we can help push the boundaries of 3D object
retrieval and facilitate more user-friendly interactions via vision-language
technologies.Comment: arXiv admin note: text overlap with arXiv:2304.0573
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