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Purpose – Brand personality plays an important role in the development of tourists’ self-image congruence and revisit intention. This paper attempts to shed light on the relationship between brand personality and self-image congruence and revisit intention through a quantitative analysis. Design – Data were collected from 496 Vietnamese tourists who visited the top five tourist sites in Vietnam, including Ha Long, Phu Quoc, Sapa, Nha Trang, and Hoi An. Methodology – By using SEM in AMOS version 24 CFA was performed to test the the overall measurement model. Findings – Multivariate data analysis demonstrated that five dimensions of brand personalitỵ (Excitement, Sincerity, Sophistication, Competence, and Ruggedness) have a positive effect on self-image congruence and revisit intention. While excitement appears to be most helpful for developing self-image congruence, sincerity has the highest benefit for increasing revisit intention, sincerity has the highest utility for increasing revisit intention. In addition, revisit intention is most influenced by excitement and least influenced by sophistication through selfimage congruence. Originality of the research – The findings highlight the important role of attributes associated with tourist destinations. Managers in the tourism sector should be familiar with these characteristics in order to position or strengthen their destination’s brand with the aim of delivering to each tourist group a customized experience that resonate with their shared values. The insights provided by this paper also have important implications for travel companies in the gradual recovery of the country’s smoke-free industry under the conditions of the COVID -19 pandemic.

Rice husk (RH) is well known as a by-product of rice production, and a large amount of RH is discharged in Southeast Asian countries yearly. Therefore, converting rice husks into valuable materials is challenging for governments. In this study, porous silica (PS) fabricated from RH was modified by ethylenediaminetetraacetic (EDTA) with binder polyvinyl alcohol (PVA) to enhance adsorption performance. The PS was an amorphous and porous material, its average particle size was about 10–20 nm, showing a pore size of about 2–5 nm. The N2 adsorption/desorption isotherm results showed that PS possessed a large specific surface of 544.5 m2/g and a high pore volume of 1.94 cm3/g. These were slightly mitigated to 496.8 m2/g and 1.44 cm3/g, respectively, for the EDTA modified porous silica composite (PS-EDTA), but it could improve the adsorption of Pb2+. The PS-EDTA 1.0 M sample had the highest adsorption performance among as-prepared samples. At optimal reaction conditions, PS-EDTA showed an adsorption efficiency of 99.98 % and a qmax of 84.70 mg/g determined by batch reaction and the Langmuir model. Besides, the kinetics, thermodynamics, and adsorption mechanism of Pb2+ on PS-EDTA were investigated.

The Galerkin-Vlasov approach based on the improved first-order shear deformation theory (i-FSDT) and nonlocal elasticity theory are proposed to investigate the free vibration response of variable-thickness fluid-infiltrated porous metal foam (FPMF) nanoplates with flexoelectricity effect resting on Pasternak elastic foundation in the hygro-thermal environment. The FPMF nanoplate thickness varies according to both the length and width directions. The novelty of the present work is to consider the influence of the nonlocal's spatial variation and flexoelectric coefficients on the free vibration behavior of the nanoplates. Based on Hamilton's principle, the governing equation of FPMF nanoplate is established. The accuracy of the proposed method is checked by comparing the obtained results with those of available work in the literature. The effects of the parameters such as the flexoelectric coefficient, nonlocal coefficient, porosity coefficient, Skempton factor, temperature and moisture, thickness variation, and various boundary conditions on the natural frequency of the nanoplate are examined.

Synthesis of silver nanoparticles (AgNPs) using plant extracts extracted from Ganoderma lucidum in the buffer zone of Bach Ma National Park, Vietnam is a simple, convenient, economical, and environmentally friendly method. This study describes the biosynthesis of silver nanoparticles in both cases with and without ultrasonic assistance using Ganoderma lucidum extract as a reducing and protective agent. Transmission electron microscopy, scanning electron microscopy, X-ray diffraction, energy-dispersive X-ray spectroscopy, and Fourier transform infrared spectroscopy were used to characterize the as-synthesized AgNPs. Compared to the heating reflux method, the proposed ultrasonic wave assisted heating reflux method produced AgNPs had higher efficiency, smaller and more uniform particle size 6.08 ± 1.80 nm of nm in a short synthesis time period. The antibacterial and antifungal properties of ultrasonically synthesized silver nanomaterials (US-AgNPs) were also investigated. US-AgNPs are important nanomaterials that can find many good applications in practice.

In this study, the B/ZnO nanocomposite was successfully synthesized by a simple mechanical combustion method. This material was used as a photocatalyst to degrade tetracycline, a representative of the commonly used antibiotics today. The B/ZnO composite became tighter than that of pure ZnO and formed bulk particles. The band gap energy of B/ZnO (3.05 eV) was slightly lower than that of ZnO (3.10 eV), resulting that it being easier to absorb visible light to create electron-hole pairs (h+ and e−). Therefore, the B/ZnO composite had higher photocatalytic activity than pure ZnO. The ratio of boron-doped to ZnO affecting the photocatalysis efficiency was investigated and the optimal boron content was 3 wt%, its degradation efficiency (DE) value for tetracycline hydrochloride (TCH) in 90 min and the rate constants were 90% and 0.054 min−1, respectively. The factors affecting the photocatalytic process like initial antibiotic concentration, catalyst content, and pH of the initial antibiotic solution were studied. In addition, the recovery and reuse of B/ZnO after photocatalytic treatment were also studied. Copyright © 2022 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

This study conducted simultaneous adsorption of Pb, Cd, and Cr ions using Mg/Al LDH-zeolite on contaminated soils from lead-zinc and tin mining areas. The optimal conditions were a 3% adsorbent-to-soil ratio, a 30-day incubation period, and 70% soil moisture. Characterization of the materials revealed that Mg/Al LDH-zeolite has superior physicochemical properties to natural zeolite, with a higher surface area and better adsorption capacity. Results indicated significant reductions in exchangeable heavy metal content: in lead-zinc mining area soil, exchangeable Pb decreased from 139.79 mg kg ^−1 to 10.95 mg kg ^−1 , Cd ^−1 from 1.518 mg kg ^−1 to 0.533 mg kg ^−1 , and Cr from 2.636 mg kg ^−1 to 0.461 mg/kg using Mg/Al LDH-zeolite. In tin mining area soil, exchangeable Pb decreased from 583.97 mg kg ^−1 to 48.22 mg kg ^−1 , Cd ^−1 from 0.498 mg kg ^−1 to 0.122 mg kg ^−1 , and Cr from 106.095 mg kg ^−1 to 38.038 mg/kg. Maize cultivation on post-adsorption soil showed improved growth performance, with plants exhibiting increased height and ear and reduced heavy metal accumulation in roots, shoots, and grains. Pb, Cd, and Cr concentrations in maize roots decreased significantly, with Pb reducing to 0.113 mg kg ^−1 in the lead-zinc area and 0.203 mg kg ^−1 in the tin area, Cd reducing to 0.061 mg kg ^−1 and 0.037 mg kg ^−1 , respectively, and Cr reducing to 0.036 mg kg ^−1 and 0.243 mg kg ^−1 respectively. Mg/Al LDH-zeolite consistently demonstrated higher efficiency in reducing the bioavailability and translocation of heavy metals in maize tissues, confirming its potential as an effective adsorbent for soil remediation. Key mechanisms, including adsorption, surface complexation, ion exchange, precipitation, and structural incorporation, reduce metal mobility and bioavailability.

In this study, we introduce a synthesis process of bimetallic nanoparticles (BNPs) Fe/Ni and Fe/Cu utilizing concentrated Camellia sinenis extract that was optimized with a solvent ratio of ethanol/H _2 O 4/1 (v/v), a metal ratio of 5/1 (w/w), a total polyphenol content (TPC) in the solution of 12.5 g.l ^−1 , pH = 3–4, 25 °C, and the reaction time ranging from 30 min to 50 min. The structural and morphological characteristics of the resulting materials were determined using several techniques, such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive x-ray spectroscopy (EDX), x-ray diffraction (XRD), and x-ray photoelectron spectroscopy (XPS). The maximum removal efficiency of methylene blue (MB) by BNPs Fe/Ni and Fe/Cu materials was found to be 88.60% and 91.06%, respectively, at a concentration of MB = 25 mg.l ^−1 and 25 °C. According to the results of the kinetic modeling study, the adsorption process of MB on the two BNPs materials followed second-order kinetics, with the maximum adsorption capacities of MB on Fe/Ni and Fe/Cu BNPs being 26.94 mg.g ^−1 and 28.00 mg.g ^−1 , respectively.

This study examines the impact of destination prosperity level on religious tourism flows to Saudi Arabia. The model was empirically tested for a panel of 21 countries from 2000 to 2019. Dynamic panel gravity models were estimated using the Generalised Method of Moments (GMM) difference approach. The study found that the human rights index and prosperity index, word of mouth, Saudi Arabian income, origin country income and investment in tourism at the destination all had a positive and significant impact on religious tourism demand. In contrast, the cost of travel and cost of living at the destination, political risk, visa restrictions, and the relative temperature had an inverse and significant impact. The estimated coefficients suggest that Saudi Arabia should invest in high-quality services to make religious visits a more pleasant and memorable experience. The paper’s originality is in using new non-economic factors such as prosperity and human rights as well as economic factors in estimating tourism demand for religious purposes.

BackgroundDiarrheagenic Escherichia coli (DEC) is a group of bacterial pathogens that causes life-threatening diarrhea in children in developing countries. However, there is limited information on the characteristics of DEC isolated from patients in these countries. A detailed genomic analysis of 61 DEC-like isolates from infants with diarrhea was performed to clarify and share the characteristics of DEC prevalent in Vietnam.Principal findingsDEC was classified into 57 strains, including 33 enteroaggregative E. coli (EAEC) (54.1%), 20 enteropathogenic E. coli (EPEC) (32.8%), two enteroinvasive E. coli (EIEC) (3.3%), one enterotoxigenic E. coli (ETEC), and one ETEC/EIEC hybrid (1.6% each), and surprisingly into four Escherichia albertii strains (6.6%). Furthermore, several epidemic DEC clones showed an uncommon combination of pathotypes and serotypes, such as EAEC Og130:Hg27, EAEC OgGp9:Hg18, EAEC OgX13:H27, EPEC OgGp7:Hg16, and E. albertii EAOg1:HgUT. Genomic analysis also revealed the presence of various genes and mutations associated with antibiotic resistance in many isolates. Strains that demonstrate potential resistance to ciprofloxacin and ceftriaxone, drugs recommended for treating childhood diarrhea, accounted for 65.6% and 41%, respectively.SignificanceOur finding indicate that the routine use of these antibiotics has selected resistant DECs, resulting in a situation where these drugs do not provide in therapeutic effects for some patients. Bridging this gap requires continuous investigations and information sharing regarding the type and distribution of endemic DEC and E. albertii and their antibiotic resistance in different countries.

Rice husk (RH) is often mentioned as an agricultural by-product, often used in the pass as fertilizer and for raw burning. With modern science, RH have been researched and found many new potential benefits and applications. In this study, RH were used to synthesize amorphous SiO2, which was used to prepare the ZnO•SiO2 nanocomposites by a hydrothermal method. The as-synthesized materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), and N2 adsorption/desorption isotherm. Their photocatalytic properties were studied by an ultraviolet-vis spectrophotometer and a fluorescence spectrophotometer. The ZnO•SiO2 nanocomposite has an excellent ability to degrade organic substances such as dyes, antibiotics, caffeine, etc. The effects of operating parameters on the photo-degradation reaction progress, including catalyst dosage, initial dye concentration, and pH of the initial dye were investigated in detail. In addition, the photodegradation rate of the dye on the ZnO•SiO2 nanocomposite was evaluated using the pseudo-first-order model. The ZnO•SiO2 nanocomposite can be used as a photocatalyst for wastewater treatment as it detaches much more easily from the solution. [ABSTRACT FROM AUTHOR]

In this study, three types of sulfonic acid group functionalized ionic liquids (SAILs) with a different number of catalytic groups and lipophilicity were synthesized and characterized by FT-IR, NMR, and MS analyses. Their catalytic activities were studied in a model esterification of oleic acid with ethanol; heating in a microwave reactor was also used. The experimental results indicated that SAIL, with the lipophilic alkyl chain, performed the best due to its increased solubility in the reaction mixture. Microwave heating was found to be more effective than conventional heating. Recycling experiments show that these novel SAILs can be reused without significant loss of the catalytic activity.

Genomic surveillance of SARS-CoV-2 is crucial to monitor the spread of variants of concern. A new sequencing method enables cost-effective SARS-CoV-2 genomic surveillance at scale and is easily adaptable to other viruses.

An extensive literature review was conducted primarily to develop a comprehensive understanding of the quantitative behavior of residual stress (RS) distribution in weld joints. Based on prior data, various levels of the peak RS and distribution profiles were applied to a finite element analyses (FEA) model as an initial loading to evaluate the effect of RS on the Mode-I stress intensity factor (SIF), KI. The RS was not found to have a significant effect on the SIF values when the peak RS was less than 300 MPa. The enhanced effect of RS on the KI values was found to be more pronounced at a lower crack ratio, while the analytical form of the RS distribution had a minor effect. The effective boundary corrections function, FResidual, was derived under the effect of RS for 1T CT specimen for various crack geometries of the crack ratio, (a/W) of 0.2, 0.40, 0.50, 0.60, and 0.75, and with peak RS varying from 100 MPa to 600 MPa. The obtained effective function of KI can be employed to quantitatively evaluate the effect of RS on the fatigue performance of welded joints.

Abstract Background Cancer is one of the most considerable concerns because of increasing the death rate all over the world. Recent studies have disclosed that plant extracts exhibit anticancer activity through various mechanisms. Xanthium strumarium has been used by Vietnamese in herbal medicines to support the medication of infirmities. This study is to consider the secondary metabolites, antioxidant and anticancer capacities of extract from the aerial parts (stems and leaves) of X. strumarium (AP-XS). Methods AP-XS was analyzed for the presence of phytochemicals via qualitative chemical tests and determined total polyphenol and flavonoid contents. DPPH (1,1-diphenyl-2-picrylhydrazyl) quenching assay and sulforhodamine B (SRB) assay were selected to investigate antioxidant capacity and anti-proliferative activity, respectively. Besides, acridine orange-ethidium bromide (AO-EB) dual staining was applied to evaluate the ability to induce apoptosis on HepG2 cancer cells. Results Results of present study indicated that AP-XS contains the main phytochemicals such as flavonoids, tannins, saponins, alkaloids, and triterpenes. Ethanol extract had highest content of polyphenol (84.86 mg gallic acid equivalent/g dry mass), and exhibited the great total antioxidant property (IC50 = 184.13 μg/mL) and anti-proliferative activity on HepG2 cancer cells (IC50 = 81.69 μg/mL). Furthermore, the characteristics of apoptosis including shrinkage of the cell and apoptotic bodies were found following 60 h of AP-XS extract treatment through AO-EB dual staining. Conclusion The data suggest that AP-XS extract had antioxidant potential and anti-proliferative effect. The anti-proliferative property was considered to have an association with a rising of apoptosis. These results were reliable for further research on X. strumarium as a source of phytochemicals with anticancer activity potential for cancer therapeutics.

This study used the systematic review methodology to examine peer-reviewed journal articles published in the Web of Science, ScienceDirect, Springer and Emerald Insight during the 2000–2020 period to analyse greenwashing. In an open market, the behaviours of state-owned enterprises (SOEs), private firms and multinational corporations (MNCs) pose an implicit greenwashing threat. Our focal point is to analyse corporate greenwashing in MNCs in host emerging markets, particularly in Asia, for two reasons. First, reports of greenwashing have increased around the world since Volkswagen was revealed to have falsified automobile emissions data. Second, MNCs play an important role in expanding market size and their behaviour is increasingly unpredictable. The analysis shows that MNCs tend to engage in greenwashing immediately after doing business in host emerging markets characterised by restricted regulations, clear market opportunities and low competitive pressure. When greenwashing occurs, it will harm the interests of not only consumers, but also society as a whole, despite offering significant benefits to existing stakeholders. In this case, the authorities should implement regulations to confront MNCs before attracting them, which should be enforced in practice.

Honey is known as a natural sweetener agent with high nutritional value and health benefits, especially premium honey because of its desirable flavour and medicinal properties. Because of this, honey has been a target of adulteration through the mixing of low-quality honey and mislabelling of the honey’s origin. The aim of this research considers the potential of using mineral and physicochemical data to authenticate the origin of honey. To this end, 40 samples of 8 botanica collected from 18 different regions of Vietnam were analysed for its metal contents (Na, K, Mg, Ca, Al, Cu, Fe, Mn, Zn, Pb, Cd, Ni, Cr, Co, As, Hg) and physicochemical parameters (pH and electrical conductiv.ity). The data were processed by multivariate analysis, which allowed the classification of honey according to its botanical origin

Background: Risk communication is necessary to improve the booster vaccination rate, but Vietnam does not have a system to collect and disclose such information. Therefore, the purpose of this study was to clarify adverse reactions and their frequency in the early period after booster vaccination, and to obtain primary data for improving the booster vaccination rate. Methods: A cross-sectional survey was conducted among adults aged ≥18 years. Clinical data were collected 14 days after booster vaccination by using a standard questionnaire. Results: A total of 1322 participants were included with median age = 23 and sex ratio (Male/Female) = 0.53. AstraZeneca was the most commonly used vaccine for the first and second doses, while Pfizer was the most commonly used vaccine for booster shots. Injection site pain, fatigue, and myalgia were the most common side effect reported (71.9%, 28.1%, and 21.8%, respectively). Compared to previous COVID-19 vaccine injections, 81.9% of participants reported that their symptoms were similar or milder after receiving the booster dose. They were more likely to present injection site pain (OR = 1.43, p < 0.0001) and lymphadenopathy (OR = 4.76, p < 0.0001) after receiving the booster shot. Fever (OR = 0.33, p < 0.0001) and fatigue (OR = 0.77, p = 0.002) were less often reported after booster shots compared to the first and second injections. The severity of symptoms occurring after booster dose versus first and second doses increased significantly with each additional year of age and among participants receiving the Pfizer and Moderna vaccines. Conclusion: Adverse reactions to booster vaccination are minor and their incidence is the same as for the first or the second vaccination. Multicenter studies with larger sample sizes on the side effects and safety of COVID-19 vaccine booster shots need to be conducted to make the population less worried, in order to increase the vaccination rate, to protect individuals’ and communities’ health.

Rare earth elements (REEs) are strategically critical in the manufacture of advanced materials. Red mud and end-of-life NdFeB magnets can be good secondary sources for REEs, but recovery is difficult due to the high iron oxide content and small amount of REEs. Oxide mixtures whose composition of Fe, Nd, and Ga was similar to that in red mud were employed in experiments. In this study, a relatively inexpensive non-aqueous system was used to selectively dissolve Nd2O3 in a mixture with Fe2O3 and Ga2O3. The addition of ethylene glycol (EG) to HCl and H2SO4 solution depressed the dissolution of Fe2O3 and Ga2O3 from the mixtures, and thus selective dissolution of Nd2O3 was possible. The optimum conditions were as follows: (a) 1.0 M HCl in EG, 25 °C ± 1 °C, 50 g/L pulp density, 120 min, 200 rpm; and (b) 0.05 M H2SO4 in EG, 25 °C ± 1 °C, 50 g/L pulp density, 60 min, 300 rpm. Under these conditions, Nd2O3 was completely dissolved, whereas no Fe2O3 or Ga2O3 was dissolved by the H2SO4 system, and the dissolution percentage of these two oxides by the HCl system was less than 1%. Due to the selective dissolution of Nd2O3 from the oxide mixtures, it is simple to recover Nd. An efficient process can be developed for the recovery of REEs from red mud and end-of-life NdFeB magnets by applying our results.

Tellurite is highly toxic to most bacteria owing to its strong oxidative ability. However, some bacteria demonstrate tellurite resistance. In particular, some Escherichia coli strains, including Shiga toxin-producing E. coli O157:H7, are known to be resistant to tellurite. This resistance is involved in ter operon, which is usually located on a prophage-like element of the chromosome. The characteristics of the ter operon have been investigated mainly by genome analysis of pathogenic E. coli; however, the distribution and structural characteristics of the ter operon in other E. coli are almost unknown. To clarify these points, we examined 106 E. coli strains carrying the ter operon from various animals. The draft genomes of 34 representative strains revealed that ter operons were clearly classified into four subtypes, ter-type 1–4, at the nucleotide sequence level. Complete genomic sequences revealed that operons belonging to three ter-types (1, 3, and 4) were located on the prophage-like elements on the chromosome, whereas the ter-type 2 operon was located on the IncHI2 plasmid. The positions of the tRNASer, tRNAMet, and tRNAPhe indicated the insertion sites of elements carrying the ter operons. Using the PCR method developed in this study, 106 strains were classified as type 1 (n = 66), 2 (n = 13), 3 (n = 8), and 4 (n = 17), and two strains carried both types 1 and 2. Furthermore, significant differences in the minimum inhibitory concentration (MIC) of tellurite were observed between strains carrying ter-type 4 and the others (p < 0.05). The ter-type was also closely related to the isolation source, with types 2 and 4 associated with chickens and deer, respectively. This study provided new insights related not only to genetic characteristics of the ter operons, but also to phenotypic and ecological characteristics that may be related to the diversity of the operon.

Background: Ornithine transcarbamylase deficiency (OTCD) is an X- linked recessive disorder and the most common error of the urea cycle, caused by the mutations in the OTC gene. Due to X-inactivation, 15–20% of female carriers present symptoms of OTCD at late onset. Early diagnosis of OTCD by molecular analysis in females is highly desirable. The aim of the study was to identify the mutations in two unrelated Vietnamese girls suspected with OTCD and the carriers in their families for definitive diagnosis and proper counseling.Case Presentation: Two patients presented with an acute encephalopathy at the first admission. Biochemical tests revealed hyperammonemia, hyperlactatemia, elevated glutamine level, elevated transaminase, elevated urinary orotic and uracil acid levels, and disorder of prothrombin time. Brain magnetic resonance imaging indicated cerebral edema. Based on the clinical and laboratory results, the two patients were diagnosed with urea cycle disorders. Therefore, the two patients were managed by stopping feeding, with infused glucose, l-carnitine, l-arginine, and sodium benzoate, and with hemofiltration. The two patients were alert and recovered with normal blood ammonia levels after 72 h of treatment. The family history of patient 1 showed that her brother died at 4 days of age due to a coma and dyspnea, while her parents were asymptomatic. Variable phenotypes were observed in three generations of the patient 2's family, including asymptomatic (mother), affected female adults dying at the first symptom (grandmother and aunt), and affected males dying in the first week of life (uncle, cousin, and siblings). Whole-exome sequencing showed two mutations in the OTC gene, including one novel missense mutation, c.365A>T, in the patient 1 and one previously reported splicing mutation, c.717+1G>A, in the patient 2. The two mutations are evaluated as likely pathogenic and pathogenic, respectively, according to the recommendations of the American College of Medical Genetics and Genomics (ACMG). Genetic analyses in the families indicated the mothers were heterozygous.Conclusion: Clinical, biochemical, and molecular findings accurately diagnosed the two patients with late-onset OTCD. Our results explained the genetic causes and proposed the risk in the patients' families, which could be useful for genetic counseling and monitoring in prenatal diagnosis.