Allelic polymorphism of crtRB1 and LcyE genes related to the β-carotene content in Vietnamese traditional maize accessions,

Maize is the third most important food crop after wheat and rice. Maize is used as food for more than a billion people around the world and is used as animal feed, especially, poultry. The concentration of carotenoids, especially, β-carotene in maize grains, is very low. Therefore, the study of increasing the amount of provitamin A carotenoids including β-carotene is important. In maize, different alleles of crtRB1 and LcyE genes have a significant effect on β-carotene content. In this paper, we present the results of the study of allele polymorphism of these two genes related to the provitamin A carotenoid content in some traditional maize accessions collected from several regions in North and Central Highlands of Vietnam. The results showed that there were polymorphisms at the 3’ and 5’ ends of the crtRB1 and LcyE genes. Among 22 maize accessions, the proportion of favorable alleles at the 3’ end of crtRB1 gene was relatively high (5/22 = 22.73%). Similar results were obtained for alleles at 3’ end of the LcyE gene. Especially, there is an accession (Northern white gold maize) that carries favorable alleles at the 3’ ends of both crtRB1 and LcyE genes. While all investigated maize accessions did not carry favorable alleles at the 5’ end of both crtRB1 and LcyE genes. The identification of traditional maize accessions that carry favorable alleles for increasing b-carotene content opens up potential to exploit indigenous genetic resources for genetic research as well as to develop maize varieties with high β- carotene content.

Essays on risk attitudes, knowledge, extreme weather, and farmers' behaviors in rural Southeast Asia

Northeastern Thailand and Central Vietnam are two regions where pockets of poverty persist despite overall success in poverty reduction on the national level. While there are profound structural differences between Thailand and Vietnam, a common feature for both countries is that government policies promote the migration of rural labor to facilitate growth in the industrial and service sectors. Furthermore, policymakers in both countries have the vision to transform their agriculture towards large-scale farming, following the model of western agriculture. While out-migration from rural areas has taken place and the share in off- and non-farm income in total household income has been growing, the share of agriculture income in many cases is now less than 50 %. To date, labor rather than land (as in the past) is the main income-generating factor. However, agriculture still plays an essential role in the rural areas of these two countries. Farms are still small, and farm sizes almost remained the same over the past decades. Structural transformation of the rural areas as envisaged by policymakers does not take place. Households keep their agriculture as a backup and safety net and hence small-scale farming continues to dominate. At the same time, farmers in the two regions are increasingly exposed to severe weather events caused by climate change which makes them vulnerable to poverty and food insecurity (ADB, 2009; IPCC, 2014a; Blanc & Reilly, 2017). In this study, it is therefore aimed to obtain a better understanding of farmers' decision-making in agriculture. In particular, the thesis aims to investigate how farmer knowledge and skills and their risk attitudes, on the one hand, and the increasingly occurring extreme weather events, on the other hand, influence their decision-making with regard to farm management decisions. There are three specific research questions to be answered in this research: (1) how do risk attitudes affect household decision-making; (2) what is the impact of agricultural knowledge on agricultural production; (3) how do farmers manage their agricultural inputs in response to extreme weather events. To answer these questions, the thesis draws on two primary data sources. The first is the database of the Thailand Vietnam Socio Economic Panel (TVSEP) project during the period of 2007 to 2017, i.e., six-year panel dataset was collected from some 4,400 rural households in the Northeastern Thailand provinces of Nakhon Phanom, Ubon Ratchathani, and Buri Ram; and in Vietnam’s Central Coastal and Central Highlands provinces of Ha Tinh, Thua Thien Hue (Hue), and Dak Lak. The second data source is historical weather data. We use the monthly high-resolution (0.5) temperature and precipitation data observed from 1948 until 2016 from the Global Precipitation Climatology Centre (GPCC; Schneider et al., 2018), and the Global Historical Climatology Network Monthly - Version 2 and the Climate Anomaly Monitoring System (GHCN + CAMS; Fan & Dool, 2008), respectively. The results of the thesis are presented in three essays. The first essay is “Risk attitudes and implication for livelihoods strategy – evidence from two provinces in Thailand and Vietnam.” Utilizing an Ordinary Least Square (OLS) and a Probit regression with different alternative specifications, the determinants of risk preference for household decision-making are analyzed. Results show that risk attitudes are significantly related to individual characteristics such as age, gender, height, and household wealth. There are correlations between the willingness to take risk and real-life decisions of farm households. The findings show that risk-seeking individuals likely diversify income-generating activities as a cushion against the risk of small-scale farmers in these areas. They invest in self-employment and other non-farm enterprises while still capitalizing in agriculture. The second essay, named “Farmers’ knowledge and farm productivity in rural Thailand and Vietnam”, investigates the relationship between farmers’ knowledge, skills, and agricultural productivity. This paper uses primary data on agricultural knowledge and skill tests among “TVSEP households” in the provinces of Ubon Ratchathani in Thailand and Hue in Vietnam. A Two-Stage Least Squares (2SLS) approach combining knowledge and skills test results with productivity data of later waves was developed to identify the effects of agricultural knowledge and skills on agricultural productivity. The major finding is that technical knowledge in agriculture is significantly and positively associated with profit but significantly negative with rice yields and cost of input costs. This suggests that knowledgeable farmers may strive for optimal rather than maximum yield and are more judicious in the use of inputs which is good for the economy and the environment. In the third essay, named “Extreme weather and agricultural input management in rural Thailand and Vietnam: Intensify or de-intensify?” we investigate the impact of extreme weather events, namely drought, on household input management decisions in Northeastern Thailand and Central Vietnam. Eight inputs are captured: land, labor (household labor and hired labor), chemicals (i.e., fertilizer and pesticides), irrigation, machinery, and other agricultural investments. We define two binary drought indicators, namely severe drought and extreme drought, using the Standardized Precipitation Evapotranspiration Index (SPEI) as the criterion. We then use Fixed Effects (FE) model for this paper’s purpose. Results indicate that farmers tend to de-intensify agricultural production in terms of hired labor, pesticides, number of crops grown, and agricultural investments in response to severe droughts. Second, farmers increasingly hire machinery as a substitute for owned equipment and for household labor. Third, the magnitude of the effects increases with the severity of drought. Differentiating the analysis between countries, and upland versus lowland rice production, shows that the level of de-intensification varies. For example, Thai farmers allocate more family and hired labor to agricultural production; Vietnamese farmers invest in agricultural assets. Upland rice farmers focus on several inputs such as pesticides, machinery, and agricultural assets, while lowland farmers focus on available irrigation systems. All three essays have generated important policy messages for Governments in both countries to consider public support measures to strengthen rural households coping strategies toward extreme weather events and climate change

Systematic coarse-graining and dynamical simulations of anisotropic molecules with applications in organic semiconductors

Organic semiconductors are used widely in different applications, including organic photovoltaics (OPVs), devices that convert solar energy to electricity. These devices, if applicable commercially, can help to supply the world’s energy needs without requiring complicated manufacturing and maintenance. Moreover, OPVs possess several useful physical properties such as being light weight, highly transparent, and flexible. This makes organic electronic devices advantageous over those made of inorganic hard materials, especially in applications in which these conditions are required. Although experimental studies show that organic semiconductors can potentially yield high performing devices, the electronic processes that govern the conversion of light to energy are not fully understood. Specifically, how free electrons are created and transferred within the device when a photon is absorbed is strongly debated in the literature. Many experimental and theoretical results have shown that microstructure at the interfaces between the component organic semiconductor materials that make up the device plays an important role in these processes. The microstructure can be induced by directional forces between generally anisotropic organic-semiconductor molecules, combined with translational symmetry breaking at interfaces. In Chapter 3, the interface of a high-performing electron donor–acceptor OPV system consisting of two small organic semiconductors benzodithiophene quaterthiophene rhodanine (BQR) and [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) is studied using classical molecular dynamics (MD). Atomistic simulations at high temperatures indicate that the "face-on" configuration is more favorable at a liquid–solid interface between the materials. In addition, molecules close to the interface are less ordered with respect to one another than those far from the interface. These factors may benefit charge separation and transport, resulting in good device performance. In general, atomistic simulations are not feasible for studying donor–acceptor interface formation for the typical domain sizes found in devices. A solution to this is to use coarsegrained (CG) models, which increases the simulation efficiency by replacing a collection of atoms as a single interacting site. In Chapter 4, a new systematic methodology to generate CG models for MD simulations is introduced and validated, which constitutes the main result of this thesis. This algorithm is developed so that MD simulations can be simplified but still accurately represent the physical and thermodynamic properties of the simulated materials. More importantly, this method can produce models that capture the anisotropy of molecules, which is especially useful for theoretical studies of organic materials and has not previously been achieved via a systematic algorithm. To validate the method, a CG model of a simple anisotropic organic molecule (benzene) is produced in Chapter 5. Simulations using this model accurately describes the structural and thermodynamic properties of the FG model and is an improvement over previous CG benzene models. A future application of this method will be the study of the interface structure of materials in OPV systems on realistic time and spatial scales compared to experimental conditions. Ultimately, the studies presented in this thesis work towards the same goal, which is to discover optimal molecular design rules to increase the power conversion efficiency of OPVs.Thesis (MPhil) -- University of Adelaide, School of Physical Sciences, 201

EVALUATING FUTURE WATER QUALITY OF URBAN RIVERS IN HANOI UNDER EFFECT OF URBANIZATION AND CLIMATE CHANGE - THE APPLICATION OF WEAP MODEL FOR CAU BAY RIVER

Every day, up to 750,000 cubic meters of wastewater in Hanoi metropolitan areas is discharged directly into rivers and lake, of which only 10% is treated to the Vietnamese standards. According to the water drainage development master plan for the capital city of Hanoi until 2030, the government aim at dealing with flooding and improve environmental sanitation for local residents. With respect to the baseline and Master plan implementation scenarios, this study evaluates the future water quality of urban rivers in Hanoi under the effect of urbanization and climate change using Water Evaluation And Planning tool (WEAP) and take the Cau Bay catchment as the case study. The result shows that, without implementation of wastewater treatment plant, the water quality of Cau Bay River will be worse with the DO in dry season is 0.2-1.2 mg/l and BOD is 52.0-55.0 mg/l. With the implementation of Master plan, the level of DO and BOD would be 7.1-7.3 mg/l and 7.0-13.8 mg/l respectively in the dry season whereas the values are 3.7 mgO/l and 36.1-41.8 mg/l in the wet season. The degradation of wastewater during the wet season is results from the combine- overflow sewage system as designed in the master plan

Discuss the Selection of Research Variables in Applying Gravity Model to Analyze Factors Affecting Specific Sector

Gravity model is an important tool for researchers interested in the impact of trade-related policies. It provides a relatively accurate result for testing and evaluating the trade-impact of various policies. In recent years, the application of the model in research has become a trend in many countries around the world, including Vietnam. Though it is considered an attractive platform for international trade researchers, its use is not without potential pitfalls. The most important thing for the application of this model is the choice of exactly which model to estimate (Sherpherd, 2019). This paper aims to systematize the development process, analyze the nature of the model, and focus on analyzing its applicability in the study of trade flows for a specific sector. Based on that, it gives some comments and evaluation on the selection of research variables in a number of recent studies which apply this model in analyzing factors affecting exports of a specific sector in Vietnam. Finally, it draws some conclusions and recommendations for the application of this model in research. Keywords: Gravity model, Structural gravity model, Theoretical foundation, Nature DOI: 10.7176/EJBM/13-10-05 Publication date:May 31st 202

Genome Sequence of a Virulent African Swine Fever Virus Isolated in 2020 from a Domestic Pig in Northern Vietnam

This study reports the genome sequence of an isolated African swine fever (ASF) virus (VNUA-ASFV-05L1/HaNam) obtained at the fourth passage on pulmonary alveolar macrophages. The virus was isolated during a typical acute ASF outbreak in pigs in a northern province of Vietnam in 2020

Aplicação da habilidade de metacognição em métodos de solução de problemas para estudantes do ensino médio

Currently, policy makers around the world are trying to reform the educational system in general and Mathematics education in particular to create a fundamental change in the content, curriculum and students’ methods of learning Mathematics. Innovative efforts in Mathematics education focus on helping students develop the core competencies of the 21st century to create more educational and career choices for students in the future. Metacognition or thinking about thinking refers to an individual's ability to control his or her thinking processes, especially the perception of choosing and using problem-solving strategies. To find solutions to the problems mentioned, a number of studies have focused on understanding the role of metacognition in problem solving activities in the teaching process of Mathematics. In this study we will explore some metacognitive models in Mathematics education, therefor, we research “Application of metacognition skill to methods problem solution for secondary school students”.Actualmente, los responsables políticos de todo el mundo están tratando de reformar el sistema educativo en general y la educación matemática en particular para crear un cambio fundamental en el contenido, el plan de estudios y los métodos de aprendizaje de las matemáticas por parte de los estudiantes. Los esfuerzos innovadores en la educación matemática se centran en ayudar a los estudiantes a desarrollar las competencias básicas del siglo XXI para crear más opciones educativas y profesionales para los estudiantes en el futuro. La metacognición o pensamiento sobre el pensamiento se refiere a la capacidad de un individuo para controlar sus procesos de pensamiento, especialmente la percepción de elegir y utilizar estrategias de resolución de problemas. Para encontrar soluciones a los problemas mencionados, una serie de estudios se han centrado en comprender el papel de la metacognición en las actividades de resolución de problemas en el proceso de enseñanza de las matemáticas. En este estudio exploraremos algunos modelos metacognitivos en la educación matemática, para ello investigamos “Aplicación de la habilidad metacognitiva a métodos de solución de problemas para estudiantes de secundaria”.Atualmente, os formuladores de políticas em todo o mundo estão tentando reformar o sistema educacional em geral e a educação matemática em particular para criar uma mudança fundamental no conteúdo, no currículo e nos métodos de aprendizagem de matemática dos estudantes. Esforços inovadores na educação em Matemática concentram-se em ajudar os estudantes a desenvolver as competências centrais do século 21 para criar mais opções educacionais e de carreira para os estudantes no futuro. Metacognição ou pensar em pensar refere-se à capacidade de um indivíduo de controlar seus processos de pensamento, especialmente a percepção de escolher e usar estratégias de resolução de problemas. Para encontrar soluções para os problemas mencionados, vários estudos se concentraram na compreensão do papel da metacognição nas atividades de resolução de problemas no processo de ensino de Matemática. Neste estudo vamos explorar alguns modelos metacognitivos na educação matemática, por isso, pesquisamos “Aplicação da habilidade de metacognição em métodos de solução de problemas para estudantes do ensino médio”

Stability of positive equilibrium of a Nicholson blowflies model with stochastic perturbations

This paper is concerned with the stability problem of the positive equilibrium of a Nicholson's blowflies model with nonlinear density-dependent mortality rate subject to stochastic perturbations. More specifically, the existence of a unique positive equilibrium of a Nicholson's blowflies model described by the delay differential equation \begin{equation*} N'(t)=-\left(a-be^{-N(t)}\right)+\beta N(t-\tau)e^{-\gamma N(t-\tau)} \end{equation*} is first quoted. It is assumed that the underlying model in noisy environments is exposed to stochastic perturbations, which are proportional to the derivation of the state from the equilibrium point. Then, by utilizing a stability criterion formulated for linear stochastic differential delay equations, explicit stability conditions are obtained. An extension to models with multiple delays is also presented

PREPARATION OF ORAL CURCUMIN DELIVERY FROM 3D-NANO-CELLULOSE NETWORKS MATERIAL PRODUCED BY ACETOBACTER XYLINUM USING OPTIMIZATION TECHNIQUE

Objective: To prepare oral curcumin delivery and optimize curcumin loading of 3D-nano-cellulose networks material (3DCM) by looking into the impact of process variables on the response utilizing response surface methodology (RSM) and Box-Behnken design. Methods: Optimization of curcumin loading of 3DCM was conducted using RSM and Box-Behnken model. Impact of four independent variables, including, the concentration of curcumin (X1), temperature (X2), shaking speed (X3), and time of loading (X4), was studied on one dependent response, that is, an amount of loaded curcumin (Y). Characterization of optimized 3DCM including curcumin was examined by Scanning Electron Microscopy (SEM) and Fourier Transform Infrared (FTIR) analysis . Results: R2 value for Y was approximately 0.94. X1 possessed the biggest positive impact compared to X2, X3 and X4. Optimized conditions for curcumin loading of 3DCM were X1 at 3 mg/ml, X2 at 40 °C, X3 at 120 rpm and X4 at 120 min. SEM photograph of 3DCM surfaces were found including fibers creating a 3D network structure. FTIR spectra studies depicted that there was no interaction between curcumin and 3DCM. Conclusion: The data obtained in this study thus suggest that curcumin loaded 3DCM was successfully fabricated to give a potential oral delivery system of curcumin

Stability of positive equilibrium of a Nicholson blowflies model with stochastic perturbations

This paper is concerned with the stability problem of the positive equilibrium of a Nicholson’s blowflies model with nonlinear density-dependent mortality rate subject to stochastic perturbations. More specifically, the existence of a unique positive equilibrium of a Nicholson’s blowflies model described by the delay differential equation N 0 (t) = − a − be−N(t) + βN(t − τ)e −γN(t−τ) is first quoted. It is assumed that the underlying model in noisy environments is exposed to stochastic perturbations, which are proportional to the derivation of the state from the equilibrium point. Then, by utilizing a stability criterion formulated for linear stochastic differential delay equations, explicit stability conditions are obtained. An extension to models with multiple delays is also presented