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This paper deals with the dynamic response of Functionally Graded Material (FGM) plates resting on a viscoelastic foundation under dynamic loads. The governing equations are derived by using Hamilton’s principle using the classical plate theory and the higher-order shear deformation plate theory. Using state-space methods to find the closed-form solution of the dynamic response of functionally graded rectangular plates resting on a viscoelastic foundation. Numerical examples are given for displacement and stresses in the plates with various structural parameters and the effects of these parameters are discussed. The result of the numerical example shows a marked decrease in displacement and stresses as the coefficient of viscous damping is increased.

Tea leaves (Camellia sinensis) have many health benefits due to their abundance of polyphenols with antioxidant activity, most notably epigallocatechin‐3‐gallate (EGCG). To protect those bioactive compounds, the spray‐drying technique of green tea‐extracted solution is conducted because of encapsulating. This study aimed to optimize the spray‐drying condition using the response surface methodology (RSM) with respect to the maximal polyphenol content of the product. Furthermore, the characterizations of resulting powder were determined. The results showed that optimal spray‐drying temperature, input flow rate, and whey protein isolate (WPI) content were evaluated at 136℃, 6.8 rpm, and 10.3% of dry basis, respectively. The obtained green tea powder products, which got from optimal spray‐drying process, achieved total polyphenol content (TPC), EGCG, and caffeine content of 322.06 mg GAE/g, 11.4%, and 2.8% of dry basis, respectively. This result revealed the feasibility of green tea leaves to produce tea powder rich in EGCG and polyphenols by spray‐drying technique, potentially contributing to the diversification of tea products., The spray‐drying process to make tea powder from the extract was optimized by RSM with response of total polyphenol. The tea powder product shows attractive characterization of remained total polyphenol, chlorophyll, EGCG, and caffeine.

Nowadays, resistant starch (RS) has been widely produced using the physical modification methods and applied for producing low-carb foods. In this study, quality and digestibility of cookies supplemented with 20% of native, heat–moisture treated, and citric acid and heat-moisture combined treated starches (NS, HS, and AHS, respectively) were investigated. Composite flours had lowered swelling index and increased water absorption values than did the wheat flour. Both maximum and final viscosities of the paste with 20% AHS substitution were significantly lower than those with 20% NS or 20% HS substitution. Resistant starch contents increased from 8.0% of the control cookie to 10.6%, 18.4% or 25.4% of the cookies substituted with 20% NS, 20% HS or 20% AHS, respectively. The cookie substituted with 20% AHS was a medium Glycemic Index (GI) food, whereas the cookie substituted with 20% NS or HS was the high GI food, similar to the control cookie. Although the cookie substituted with 20% AHS had lower volume than the control cookie, their sensory quality values were not significantly different. Thus, the combined acid and heat–moisture treated sweet potato starch could be substituted for 20% of wheat flour to increase the RS content and reduce the GI values of cookies as compared to those of the native or heat–moisture treated starch.

Integrated marketing communication has received increasing research attention to clarify its role in business, especially in hospitality. This paper studies the effect of integrated communication on marketing results, through a survey with the participation of luxury hotel managers in Hanoi, thereby proposing and testing a scale and two research models. As a result, the research develops an integrated marketing communication scale that approaches the management process from a firm-wide approach, clarifying the positive effect of integrated marketing communication on marketing performance. The research then provides useful suggestions for managers to perfect integrated marketing communication and improve marketing performance.

Plus tree selection is the first step to improve production and quality in forestry. An individual-based method is widely used to select plus trees for timber production, timber form, freedom from diseases and insects. In this study, a method to select plus trees for flower production is described and named as a crown-area-based method. Both individual-based and crown-area-based methods were used to select plus trees for Camellia impressinervis, a golden camellia; its yellow flowers have been used to treat sore throat and diarrhea, and to prevent cancers in China and Vietnam. Flower production of 21 concerned individuals was compared to the population mean and it was generated as a percentage. The population mean of the individual-based method is the mean of production of 21 trees as mean production/tree. While population mean of the crown-area-based method is mean production/m2 crown area (first production/m2 crown area for each tree was generated, then mean for population). The results indicated that both methods show seven individual trees with flower production >100% population mean. However, individual trees are different. Only five of 7 trees are the same in both methods. The tree rankings by flower production percentage in both methods are totally different. The highest ranking by individual-based method (310% mean) is 4th ranking by crown-area-based method (181% mean). While the highest ranking by crown-area-based method (270% mean) is third ranking by individual-based method (260% mean). It is concluded that crown-area-based method is better in selecting plus trees for flower purpose, as it considers the crown area which is known as a productive part of a tree to form flowers.

Biotic and abiotic factors control aboveground biomass (AGB) and the structure of forest ecosystems. This study analyses the variation of AGB and stand structure of evergreen broadleaved forests among six ecoregions of Vietnam. A data set of 173 1-ha plots from 52 locations in undisturbed old-growth forests was developed. The results indicate that basal area and AGB are closely correlated with annual precipitation, but not with annual temperature, evaporation or hours of sunshine. Basal area and AGB are positively correlated with trees > 30 cm DBH. Most areas surveyed (52.6%) in these old-growth forests had AGB of 100–200 Mg ha−1; 5.2% had AGB of 400–500 Mg ha−1, and 0.6% had AGB of > 800 Mg ha−1. Seventy percent of the areas surveyed had stand densities of 300–600 ind. ha−1, and 64% had basal areas of 20–40 m2 ha−1. Precipitation is an important factor influencing the AGB of old-growth, evergreen broadleaved forests in Vietnam. Disturbances causing the loss of large-diameter trees (e.g., > 100 cm DBH) affects AGB but may not seriously affect stand density.

Standardized surveillance for health care-associated infections (HAI) is critical to understand HAI burden and inform prevention strategies at a national level. Due to differing and generally limited resources in Vietnam's health care facilities, implementation of HAI surveillance has been variable and data quality has not been systematically assessed. In 2016, the Vietnam Administration for Medical Services (VAMS) under the Ministry of Health, with the support of partners, began to establish a context-appropriate, standardized HAI surveillance system for bloodstream infections (BSI) and urinary tract infections (UTI) among 6 pilot hospitals in Vietnam. We identified 5 key elements of our HAI surveillance implementation process that have been conducive to ensuring data quality and program sustainability and scalability. These include: (1) engaging stakeholders, (2) designating roles and responsibilities, (3) developing context-sensitive, standardized surveillance protocols, (4) creating a surveillance implementation strategy, and (5) linking HAI surveillance and prevention activities. With the active participation of infection prevention and control staff from the 6 pilot hospitals, standardized HAI surveillance for BSIs and UTIs was expanded to 12 additional hospitals in 2019. Together, VAMS and partners are helping Vietnam fulfill its commitment to safe health care for all patients.