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The paper aims to present a study on the effects of temperature and salinity on the vertical distribution of suspended sand concentration and transport rate on the basis of 1DV model.

The finite difference method based on the implicit scheme of Crank‐Nicolson with an irregular grid was used for the fluid flow equation and the implicit upwind scheme with a staggered grid for the equation of concentration diffusion. The model was applied to five tests of the data sets from the Delta Flume with three different cases of temperature and salinity on the basis of parameterisation of the kinematic viscosity, the turbulence‐related sediment mixing coefficient and the concentration at the reference level.

The computed results showed that the vertical distributions of suspended sand concentration depend on salinity and specially, on temperature. When temperature increases or salinity decreases, the settling process of particles occurs considerably faster. For fine sand, the discrepancy on suspended sand transport rates due to temperature or salinity decreases with wave height. For coarse sand, the effect of temperature and salinity is not much affected by the wave height.

The quantitative evaluation of the roles of salinity, especially temperature once again confirmed their importance for the sediment transport and the process of coastal morphology. The further sense from this research may suggest some new ideas on the tendency of evolution of sea bed due to the warming of the earth in the future.

The aim is to investigate in detail the sensitivity of sediment transport and bed morphology with respect to some parameters including bed slope, non‐hydrostatic pressure term, sand grain size, temperature, salinity and lower boundary conditions for suspended sand concentration on a regional scale through numerical simulations based on a mathematical model.

The numerical model consists of a 3D hydrodynamic code amended by a sediment transport module. At the same time, the influence of wave action has been taken into account. The model is applied to the Sylt‐Romo tidal bay covering approximately 20 × 30 km² spanned by about 2.7 × 10⁶ active grid points with the constant wind and wave fields.

The computed results of seven different cases over 150 h show that the effect of bed slope correction is very strong, especially in case of largely changeable bathymetry and depends on the horizontal grid resolution. Sand grain size strongly influences the vertical distribution of suspended sediment and then sedimentation. The impact of sea water temperature is relatively clear despite being less powerful than two former parameters. Non‐hydrostatic pressure perturbations of the flow field and the kind of the lower boundary condition as well as salinity are negligible allowing for considerable savings of CPU time when the numerical simulation is carried out for a large area and for a very long‐time period.

The results of the study demonstrate that the geometrical factor of coastal bed and the range of sand particle size on the bottom contribute to the tendency of bed evolution in some measure. Additionally, the increase of temperature of sea water due to global warming may also make a considerable change to the mechanism of sediment transport and sedimentation in future. Therefore, the human intervention in the process of natural evolution is possible through the behaviour to the nature. At the same time, this is also interesting and useful information and it can consolidate the idea for coastal engineering projects.

Considers the conjugate natural convection motion of a power law fluid in a vertical finite channel, taking into account the heat transfer into channel walls as well as the effect of the existence of different heat sources distributed uniformly in the walls and in the fluid. Examines the results obtained in some test cases in more detail and shows that the influence of the wall becomes significant when the thermal conductivity of the wall is small enough. Also notes that the effect of the heat source distributed in the fluid is more considerable than in the wall.

Restructuring swine and pork value chain plays important role in agriculture reformation of Vietnam, the top global pork-lover and swine producer worldwide. This study aims at investigating the modernization of its entire swine-to-pork value chain.

This study combines the secondary data and primary data. The secondary data included the publications, procurements, databases from both worldwide and in Vietnam. Primary data comprised the results from field-trips in March 2018 and February 2019 that used in-depth interviews with representative key persons of involving stake-holders.

The prevalence of contract farming, vertical expansion and conglomerate mergers mainly boost vertical coordination in the industry, which creates three hierarchy paradigms of governance named the full- and semi-vertically integrated model, and the formal coordinating relation institution. Consequently, consolidation has occurred and lead the swine and pork value chain toward modernization.

This study generalizes its first trends of the modernization of the swine-to-pork industry instead of provides its concreted impacts to the involved stakeholders.

Swine and pork industries retain historical and socio-political issues in Vietnam. Social problems are going to raise if number of traditional swine producers are failed in the competition from the equipped large-scale producers leading by the giant vertically-integrated contractors.

This study provides the empirical synthesis of the vertical coordination in entitle swine and pork value chain of Vietnam through combining the view of the strategic alliance of the firm and global value chain governance.

The consumption of rice that contains high levels of inorganic arsenic may cause human health risk. This study aims to determine As species concentrations, particularly iAs, in raw rice in Ho Chi Minh (HCM) City and its health risks.

A total of 60 polished raw composite samples of rice were purchased from traditional markets and supermarkets in HCM City. All samples were analyzed by HPLC-ICPMS for As species determination.

Mean concentrations of inorganic arsenic in all samples, which were purchased from supermarket and traditional market, were 88.8 µg/kg and 80.6 µg/kg, respectively. Overall, inorganic arsenic level was 84.7 µg/kg and contributed the highest proportion of arsenic species in rice with 67.7%. The proportion profiles for arsenic species were: As (III) (60 %); dimethylarsinic acid (32.2 %); As (V) (7.7 %) and methylarsonic acid (0.1 %). Inorganic arsenic level in raw rice was below the recommendation of World Health Organization. Using the benchmark dose recommended by the Joint FAO/WHO Expert Committee on Food Additives (JECFA), all exposure doses were lower than BMDL05. However, as the doses ranged from 3.0 to 8.6 of Margin of Exposure (MOE), the health risk of iAs from rice consumption remains public health concern.

The study results report on the surveillance data of the presence of inorganic arsenic in raw rice products, which are available in the supermarkets and traditional markets, and its health risk to consumers in a metropolitan city in Vietnam.