ANALYSIS OF GENETIC DIVERSITY OF 26 CASSAVA VARIETIES (Manihot esculenta CRANTZ) WITH DIFFERENT RESPONSES TO WATERLOGGING CONDITIONS BY USING RAPD MARKERS

RAPD (Randomly Amplified Polymorphic DNA) is an indicator for high and stable polymorphism, widely used in the study of the diversity of cassava. In this paper, the results of using 20 polymorphic primers OPK combined with the establishment of the phylogenetic tree to analyze the genetic diversity of 26 cassava varieties with different responses to waterlogging conditions by using the RAPD-PCR technique were presented. The purpose of this experiment was to show the genetic relevance of the studied cassava varieties. The results showed that the flood tolerance of cassava was not related to the polymorphism and branching characteristics of the stem. This information may be use as a basis for selecting flood-tolerant cassava varieties for cassava production, as well as the basis for selecting genetically different parents for breeding.

A NOTE ON GENERALIZED RAINBOW CONNECTION OF CONNECTED GRAPHS AND THEIR NUMBER OF EDGES

Let l ≥ 1, k ≥ 1 be two integers. Given an edge-coloured connected graph G. A path P in the graph G is called l-rainbow path if each subpath of length at most l + 1 is rainbow. The graph G is called (k, l)-rainbow connected if any two vertices in G are connected by at least k pairwise internally vertex-disjoint l-rainbow paths. The smallest number of colours needed in order to make G (k, l)-rainbow connected is called the (k, l)-rainbow connection number of G and denoted by rck,l(G). In this paper, we first focus to improve the upper bound of the (1, l)-rainbow connection number depending on the size of connected graphs. Using this result, we characterize all connected graphs having the large (1, 2)-rainbow connection number. Moreover, we also determine the (1, l)-rainbow connection number in a connected graph G containing a sequence of cut-edges.

COMPUTER SIMULATION OF LOCAL STRUCTURE AND DIFFUSION MECHANISM THROUGH VORONOI POLYHEDRONS IN SODIUM SILICATE GLASS

The Na2O.SiO2 glass has been studied at different temperatures from 300 K to 1173 K by using molecular dynamics simulations. The Voronoi Si and O polyhedrons are analyzed to evaluate the displacement of sodium between these polyhedrons. The results show that more than 90% of the total number of Na is located in NBF polyhedrons that contain non-bridging (NBO) and free oxygen (FO) polyhedrons. The site energy for Na atoms located in NBF is smaller than one in BO polyhedron. The diffusion process of Na atoms is occurred in two ways: the first one is the alone jumping of Na in BO polyhedrons and the second one is the mixed alone jumping of Na and the cooperative movement of Na in NBF polyhedrons. The calculation of the average time between two consecutive jumps and the visiting time for Na atoms leads to the correlation effect for the diffusion of Na atoms. This effect depends on the temperature of the samples.

STABILITY OF A MATHEMATICAL MODEL DESCRIBING THE COVID-19 PANDEMIC IN TERMS OF THE ENVIRONMENT, SOCIAL DISTANCING AND REINFECTION

In this paper, we propose and study the stability of a mathematical model for the Covid-19 pandemic incorporating the environment, social distancing and reinfection. A numerical example is carried out to consider the obtained results.

GENOME-WIDE IDENTIFICATION AND COMPUTATIONAL CHARACTERIZATION OF THE NUCLEAR FACTOR-YC SUB-UNITS IN GRAIN AMARANTH (Amaranthus hypochondriacus)

Nuclear factor-Y (NF-Y) has been known as one of the plant-specific transcription factors that play key roles in numerous biological processes during the growth and development of plant species. In this study, a comprehensive analysis of NF-YC sub-units in grain amaranth (Amaranthus hypochondriacus) was carried out based on the bioinformatics approaches. Firstly, a total of five members of the NF-YC sub-units was reported in the grain amaranth. Its structural analyses revealed that the NF-YC sub-units were variable in physic-chemical properties, like protein sizes, molecular masses, isoelectric point, instability index, and grand average of hydropathy. Of our interest, the expression profiles of genes encoding NF-YC sub-units in various tissues\organs during the growth and development of grain amaranth. We found that three genes, including AhNF-YC01, AhNF-YC04, and AhNF-YC05 were highly expressed in leaf, root, floral, immature seed, and stem tissues. Interestingly, AhNF-YC05 was exclusively expressed in leaf and stem tissues. Taken together, our study could provide a solid understanding for further functional characterization of genes encoding NF-YC sub-units in grain amaranth.

AN EVALUATION OF METEOROLOGICAL DROUGHT IN DAK LAK PROVINCE

Assessment of the degree of meteorological drought in Dak Lak province is carried out using the SPI index and the water balance index K in the period 1985 - 2019. The results show that: According to the SPI index, drought tends to occur more at the time of transition from the dry season to the rainy season, during the rainy season, and from the time of transition from the rainy season to the dry season. The K-index in the period 1985 - 2019 showed there was a dry period at the beginning of the year from January to April. The anomalous drought factor plays a very important role because its large influence can cause damages, and allows assessing the variability of rainfall and the impact of climate change on the region. The study and evaluation of meteorological drought have practical significance, supporting managers in making policies on water resource management, ensuring sustainable economic and social development in the context of global climate change.

TEMPLATE-SHAPE DEPENDENCE ASSEMBLY OF JANUS NANOPARTICLES AT WATER-OIL INTERFACE

In this work, we investigated the crystal formation of anisotropic nanoparticles, namely Janus particles, at the water-oil interface using the dissipative particle dynamics simulation method. By considering three different interface templates, including planar, droplet, and rod, we observe an increase of the disorder-order transition packing fraction with increasing the curvature radius of the templates. Furthermore, the nanoparticles in the planar template assemble into a hexagonal lattice, while for the two remaining templates they aggregate into colloidsome-like structures.

THE STUDY IN DIFFUSION MECHANISM BY VORONOI POLYHEDRON IN SODIUM TETRA-SILICATE MELT

Molecular dynamic simulation is carried out for Sodium tetra-silicate (NS4) melt at 1873 K and pressure of 0.1 MPa. The diffusion mechanism of Na atoms is investigated in terms of Voronoi polyhedron around network former and displacement of Na atoms between them. The simulation shows that Na atoms are not uniformly distributed through polyhedrons, but they mainly gather in nonbridging oxygen (NBO) and free oxygen (FO) polyhedrons. More than 75.22% of total Na atoms are place in NBO polyhedrons, although the number of NBO polyhedrons is only 22.27%. The two motion types give mainly contribution to Na diffusion: hopping of isolated Na atom or collective displacement. During 150 ps, the system comprises two separate regions: Na-poor regions formed by Si-O subnets and Na-rich regions formed by O2 clusters. The two regions have strongly different chemical composition, the density of Na atoms as well as motion type of Na atoms.

VIETNAMESE Phellinus baumii FRUITING BODY, A POTENTIAL SOURCE OF ANTIOXIDANT AND α-AMYLASE INHIBITORY AGENTS

n-Hexane, ethyl acetate, and butanol fractions from methanol extract of Vietnamese Phellinus baumii fruiting body consisted of phenolics, flavonoids, and terpenoids. Ethyl acetate and butanol fractions showed a high level of total phenolics. Ethyl acetate fractions possessed the highest phenolic content (532.96 ± 19.95 mg GAE\g), accounting for approximately 53% fraction dry weight. Free radical DPPH (1,1-diphenyl-2-picrylhydrazyl) scavenging capacity of all fractions correlated with their total phenolic content. Ethyl acetate fraction exhibited the strongest capacity with an IC50 value of 0.059 mg\mL, equivalent to nearly 50% of ascorbic acid’s capacity. Its ferric reducing power was off more than half of quercetin and acid ascorbic at the concentration of 0.2 mg\mL. Ethyl acetate also had remarkable α-amylase inhibitory activity (IC50= 0.38 mg\mL). The results suggested P. baumii fruiting body as a potent source for antioxidative and α-amylase inhibitory compounds.

ASSESSMENT OF THE USE OF DRUG TREATMENT OF DYSLIPIDEMIA AT MILITARY HOSPITAL 105

Dyslipidemia characteristics of outpatients with dyslipidemia for the first time, characteristics of drug use, and effectiveness in controlling dyslipidemia indexes after 3 months of treatment at Military Hospital 105 were studied. A crosssectional, retrospective descriptive study was investigated on adult outpatients who were diagnosed with dyslipidemia for the first time, examined and treated as outpatients at the hospital, and monitored for effectiveness in blood lipid control for 3 months after starting treatment. The decision to use the drug at the start of the study and the achievement of treatment goals at the time points were analyzed based on the ESC\EAS 2019 guidelines for treating DL. The majority of patients were aged > 45 years (80.5%), the most common group of patients was aged 46 - 59 (43.7%). The number of patients with comorbidities accounted for 62.8%. 87% of patients had mixed dyslipidemia, 54.8% of patients were in the group with high and very high cardiovascular risk. 93.5% of patients needed to start treatment with drugs based on LDL-C index at the time of treatment initiation. The majority of patients used monotherapy regimens, in which, Statins were used the most in the study sample with the rate of 95.3% in the initial treatment regimen. 70.4% of patients had an inappropriate decision to initiate treatment, of which the most common was the decision to use statins with insufficient dosage in patients (45.1%). Only 28% of patients reached their LDL-C goal after 3 months of treatment. From the high percentage of patients who did not reach the treatment goal in the study sample, it is necessary to consider using stronger statin therapy, higher dose statin, or using another treatment regimen for patients.