Does rising import competition harm Vietnam’s local firm employment of the 2000s?

This study considers for the first time the role of rising import competition on employment in Vietnam. Using a time differenced and instrumental variables approach, our study shows that import competition results in employment contraction. Firms operating in industries that face greater import competition have reduced employment. We also find strong evidence of a negative impact of import competition for small and very small firms, as well as in the period before Vietnam’s World Trade Organization (WTO) accession. Our results also reveal that previous studies at the industry-level can provide biased estimates because of not controlling for the heterogeneity of firm characteristics

Synthesis of Flower-like Silver Nanostructures on Silicon and Their Application in Surface-enhanced Raman Scattering

To enhance the intensity of surface-enhanced Raman scattering (SERS), production of metal nanostructures with sharp points, lying side by side at the nanometer level plays an extremely important role. In this paper, we report on a manufacturing process in which the silver nanoparticles with the flower-like shape have been fabricated. Such silver nanoparticles have been fabricated by chemical deposition of silver particles on silicon wafers, using a solution of hydrofluoric acid (HF), silver nitrate (AgNO3) and ascorbic acid (AsA) in water, at room temperature. During the manufacturing we found that only when the concentrations of AgNO3 and AsA are appropriate, the flower-like silver nanoparticles will form. Note that while other authors mainly made flower-like silver nanoparticles in the form of suspensions, we have created flower-like silver nanoparticles with cabbage-shape on a silicon surface. The ensembles of flower-like silver nanoparticles above were used as SERS substrates to detect crystal violet (CV) in low concentrations and good results were obtained

Polymer Brushes on Silica Nanostructures Prepared by Aminopropylsilatrane Click Chemistry: Superior Antifouling and Biofunctionality

In nanobiotechnology, the importance of controlling interactions between biological molecules and surfaces is paramount. In recent years, many devices based on nanostructured silicon materials have been presented, such as nanopores and nanochannels. However, there is still a clear lack of simple, reliable, and efficient protocols for preventing and controlling biomolecule adsorption in such structures. In this work, we show a simple method for passivation or selective biofunctionalization of silica, without the need for polymerization reactions or vapor-phase deposition. The surface is simply exposed stepwise to three different chemicals over the course of ∼1 h. First, the use of aminopropylsilatrane is used to create a monolayer of amines, yielding more uniform layers than conventional silanization protocols. Second, a cross-linker layer and click chemistry are used to make the surface reactive toward thiols. In the third step, thick and dense poly(ethylene glycol) brushes are prepared by a grafting-to approach. The modified surfaces are shown to be superior to existing options for silica modification, exhibiting ultralow fouling (a few ng/cm2) after exposure to crude serum. In addition, by including a fraction of biotinylated polymer end groups, the surface can be functionalized further. We show that avidin can be detected label-free from a serum solution with a selectivity (compared to nonspecific binding) of more than 98% without the need for a reference channel. Furthermore, we show that our method can passivate the interior of 150 nm 7 100 nm nanochannels in silica, showing complete elimination of adsorption of a sticky fluorescent protein. Additionally, our method is shown to be compatible with modifications of solid-state nanopores in 20 nm thin silicon nitride membranes and reduces the noise in the ion current. We consider these findings highly important for the broad field of nanobiotechnology, and we believe that our method will be very useful for a great variety of surface-based sensors and analytical devices

Changes in the Recovery Efficiency, Nutritional and Safety Quality of Dried Sergestid Shrimp (Acetes species) during Commercial Production

The sun-dried method is popular for producing dried Sergestid shrimp in Vietnam, but maintaining consistent product quality across seasons is challenging due to its dependence on weather conditions. A previous study used convection drying at a laboratory scale. In this study, the laboratory scale was upgraded to a commercial scale, and recovery efficiency and Sergestid shrimp images were recorded during production stages. Parameters were adjusted for economic efficiency and convenience. Results showed a decrease in recovery efficiency on the laboratory scale, while the commercial scale improved with washing and blanching. Overall, there was no significant difference in recovery efficiency between the commercial production (15.76 %) and laboratory scale (16.29 %). The commercial-scale dried Sergestid shrimp exhibited better colour than the laboratory-scale product. The product met food safety and quality criteria according to Vietnamese standards. Microorganisms such as Coliforms, E. coli, B. cereus, C. perfringens and salmonella, and total number of yeast and mold spores, were not detected in the product. On the other hand, the product of commercial production contained 256 kcal 100 g−1 of energy and a protein content of 55.50 ± 0.33 %. These findings form a foundation for scaling up production and assessing economic feasibility. Adjusting production parameters using larger equipment contributes to achieving optimal production efficiency and economic benefits

Crystal structure of 4-amino-3-(thio-phen-3-ylmeth-yl)-1<i>H</i>-1,2,4-triazole-5(4<i>H</i>)-thione.

In the title compound, C7H8N4S2, the thio-phene ring shows rotational disorder over two orientations in a 0.6957 (15):0.3043 (15) ratio. The plane of the 1,2,4-triazole ring makes a dihedral angle of 75.02 (17)° with the major-disorder component of the thiophene ring. In the crystal, two types of inversion dimers, described by the graph-set motifs R22(8) and R22(10), are formed by N-H⋯S inter-actions. Chains of mol-ecules running in the [101] direction are linked by weaker N-H⋯N inter-actions. The thio-phene ring is involved in π-π and C-H⋯π inter-actions

Spatiotemporal evolution of SARS-CoV-2 Alpha and Delta variants during large nationwide outbreak of COVID-19, Vietnam, 2021

We analyzed 1,303 SARS-CoV-2 whole-genome sequences from Vietnam, and found the Alpha and Delta variants were responsible for a large nationwide outbreak of COVID-19 in 2021. The Delta variant was confined to the AY.57 lineage and caused >1.7 million infections and >32,000 deaths. Viral transmission was strongly affected by nonpharmaceutical interventions

Awareness and preparedness of healthcare workers against the first wave of the COVID-19 pandemic: A cross-sectional survey across 57 countries.

BACKGROUND: Since the COVID-19 pandemic began, there have been concerns related to the preparedness of healthcare workers (HCWs). This study aimed to describe the level of awareness and preparedness of hospital HCWs at the time of the first wave. METHODS: This multinational, multicenter, cross-sectional survey was conducted among hospital HCWs from February to May 2020. We used a hierarchical logistic regression multivariate analysis to adjust the influence of variables based on awareness and preparedness. We then used association rule mining to identify relationships between HCW confidence in handling suspected COVID-19 patients and prior COVID-19 case-management training. RESULTS: We surveyed 24,653 HCWs from 371 hospitals across 57 countries and received 17,302 responses from 70.2% HCWs overall. The median COVID-19 preparedness score was 11.0 (interquartile range [IQR] = 6.0-14.0) and the median awareness score was 29.6 (IQR = 26.6-32.6). HCWs at COVID-19 designated facilities with previous outbreak experience, or HCWs who were trained for dealing with the SARS-CoV-2 outbreak, had significantly higher levels of preparedness and awareness (p<0.001). Association rule mining suggests that nurses and doctors who had a 'great-extent-of-confidence' in handling suspected COVID-19 patients had participated in COVID-19 training courses. Male participants (mean difference = 0.34; 95% CI = 0.22, 0.46; p<0.001) and nurses (mean difference = 0.67; 95% CI = 0.53, 0.81; p<0.001) had higher preparedness scores compared to women participants and doctors. INTERPRETATION: There was an unsurprising high level of awareness and preparedness among HCWs who participated in COVID-19 training courses. However, disparity existed along the lines of gender and type of HCW. It is unknown whether the difference in COVID-19 preparedness that we detected early in the pandemic may have translated into disproportionate SARS-CoV-2 burden of disease by gender or HCW type

Safety and efficacy of fluoxetine on functional outcome after acute stroke (AFFINITY): a randomised, double-blind, placebo-controlled trial

Background Trials of fluoxetine for recovery after stroke report conflicting results. The Assessment oF FluoxetINe In sTroke recoverY (AFFINITY) trial aimed to show if daily oral fluoxetine for 6 months after stroke improves functional outcome in an ethnically diverse population. Methods AFFINITY was a randomised, parallel-group, double-blind, placebo-controlled trial done in 43 hospital stroke units in Australia (n=29), New Zealand (four), and Vietnam (ten). Eligible patients were adults (aged ≥18 years) with a clinical diagnosis of acute stroke in the previous 2–15 days, brain imaging consistent with ischaemic or haemorrhagic stroke, and a persisting neurological deficit that produced a modified Rankin Scale (mRS) score of 1 or more. Patients were randomly assigned 1:1 via a web-based system using a minimisation algorithm to once daily, oral fluoxetine 20 mg capsules or matching placebo for 6 months. Patients, carers, investigators, and outcome assessors were masked to the treatment allocation. The primary outcome was functional status, measured by the mRS, at 6 months. The primary analysis was an ordinal logistic regression of the mRS at 6 months, adjusted for minimisation variables. Primary and safety analyses were done according to the patient's treatment allocation. The trial is registered with the Australian New Zealand Clinical Trials Registry, ACTRN12611000774921. Findings Between Jan 11, 2013, and June 30, 2019, 1280 patients were recruited in Australia (n=532), New Zealand (n=42), and Vietnam (n=706), of whom 642 were randomly assigned to fluoxetine and 638 were randomly assigned to placebo. Mean duration of trial treatment was 167 days (SD 48·1). At 6 months, mRS data were available in 624 (97%) patients in the fluoxetine group and 632 (99%) in the placebo group. The distribution of mRS categories was similar in the fluoxetine and placebo groups (adjusted common odds ratio 0·94, 95% CI 0·76–1·15; p=0·53). Compared with patients in the placebo group, patients in the fluoxetine group had more falls (20 [3%] vs seven [1%]; p=0·018), bone fractures (19 [3%] vs six [1%]; p=0·014), and epileptic seizures (ten [2%] vs two [<1%]; p=0·038) at 6 months. Interpretation Oral fluoxetine 20 mg daily for 6 months after acute stroke did not improve functional outcome and increased the risk of falls, bone fractures, and epileptic seizures. These results do not support the use of fluoxetine to improve functional outcome after stroke

Secondary consolidation of soft soils in salt-affected conditions related to sea lever rise, case study: hanoi soft soils

In the scenario that inland areas along a coastline are affected by saline water, ground consolidation and deformation arechanged. The authors simulated the influence of saline intrusion to ground on geotechnical properties of soils by a case study of soft soils at 9 sites in Hanoi. Specimens were processed by making saturation with artificial seawater of four salt concentration levels, followed byexperiments using X-ray diffraction and one-dimensional consolidation. The results showed that the secondary consolidation  is increased in the Hanoi salt-affected soft soils. The higher salt concentration of saturated solution is applied, the higher deformation occurred. This was interpreted based on clay minerals composition present in the soils.ReferencesAl-Shamrani M.A. Dhowian A.W., 1996: Characterization of secondary compression behavior of Sabkhasoils. Engineering Geology 48 (1-2), 19-41. Azam S., 2000: Collapse and compressibility behavior of arid calcareous soil formations. Bulletin Eng. Geol. Env. 59, 211-217. Brouchkov A., 2003: Frozen saline soils of the arctic coast: their distribution and engineering properties. Proceedings - 8th International Conference on Permafrost, p. 95-100. Zurich, Switzerland. Dhowian A.W., 1991: Secondary compression of Sabkha saline soils. Engineering Geology 30, 155-169. Dương Thị Toan, Nguyễn Ngọc Trực, 2010: Ảnh hưởng của nước biển đối với các tính chất đất đồng bằng sông Hồng. Tạp chí Khoa học và Công nghệ, tr.215-223. Gbenga M. A., Oluwole A. A., Shodolapo O. F., 2009: Influence of Calcium Sulphate on Subsoil Cohesion and Angle of  Friction. Journal of Applied Sciences Research, 5(3), 297-304. Germanov T. S., Kirov B. L., 1985: Influence of Waste Waters on Soil Consolidation, Proc. of  XIth ICSMFE, A. A. Balkema, pp. 2407-2409. San Francisco, USA. Hideo K., 2007: Vulnerability of Riverbank Material by Sea Level Rising due to Global Warming in Japan. Proc. of the 2nd Malaysia-Japan Symposium on Geohazards and Geoenvironmental Engineering, pp. 209-212. Langkawi, Malaysia. James K. M., Kenichi S., 2005: Fundamentals of Soil Behavior, 3rd edition, Wiley. New York, USA. Kirov B. L., 1989: Influence of Waste Waters on Soil Deformation. Proc. of XII ICSMFE, pp. 1881-1882. Rio de Janeiro, Brazil. Kirov B. L., Truc N. N., 2012: A Study on the Relationship between Geotechnical Properties and Clay Mineral Composition of Hanoi Soft Soils in Saline Media. Inter. Journal of Civil Engineering, Vol. 10 (2), pp. 87-92. Mesri G., Godlewski P. M., 1977: Time and Stress Compressibility Interrelationship, Journal of Geotechnical Engineering, ASCE, 105 (1), pp.106-113. Mesri, G., 1973: Coefficient of Secondary Compression, Journal of Soil Mech. and Found. Div., 99(1), pp.123-137. Rashid M. A., Buckley D. E., Robertson K. R., 1972: Interactions of a marine humic acid with clay minerals and a natural sediment. Geoderma,Vol. 8 (1), pp. 11-27. Truc N. N., Granie R. J., 2008: Global Warming - Related Sea Level Rise and The Change of Some Mechanical Characteristics of Soil Foundation Due to Salty Intrusion, Case Study Thai Binh Formation Sediment in The RRD, Vietnam. In: Giao PH, editor, Proc. of Int. Sym. on Climate Change and the Sustainability, pp. 131-140. Hanoi, Vietnam. Truc N. N., Hung D. N., 2007: The Issue of Sea Level Rise Due to Global Warming and Its Impacts on The Coastal Zone of Vietnam. In: Giao PH, editor, Proc. of Int. Sym. on Hanoi Geoengineering, pp.124-130. Hanoi, Vietnam. Van Hoorn J. W., Van Alphen J. G., 1994: Salinity Control. In Ritzema HP editor. Drainage Principles and Applications, ILRI Publication 16 (2nd edition), pp. 533-600. Wageningen, The Netherlands. Yeliz Y. A., Kaya A., Ören A. H., 2008: Seawater Effect on Consistency Limits and Compressibility Characteristics of Clays, Engineering Geology, pp. 54-61.