Hue University Journal of Science: Natural Science

Identification and characteristics of MYB4 transcription factor related to regulation of abiotic stress tolerance in peanut

Hoang Kha — 2024-06-27

Peanut (Arachis hypogaea L.), an economically valuable crop, provides protein and oil for human and animal consumption. The transcription factor MYB4 has been identified as a potential drought tolerance gene in peanut. This study aimed to isolate and characterize the MYB4 gene in the L14 peanut cultivar. The isolated AhL14_MYB4 gene was found to be 1.1 kb long, with a 663 bp coding sequence containing 3 exons and 2 introns. In silico analysis showed that AhL14_MYB4 possesses a nuclear localization signal and two DNA-binding domains characteristic of transcription factors. The findings revealed key molecular features of AhL14_MYB4 and provided insights into improving drought resistance in peanut varieties. Further research on AhL14_MYB4 may aid efforts to enhance drought tolerance in local peanut cultivars through molecular breeding or genetic engineering. Overall, this finding about preliminary characterization of the peanut MYB4 gene lays the groundwork for potential genetic improvements to this economically important crop.

Effects of planting densities and regenerations on the growth and yield of Brachiaria humidicola grown in Thua Thien Hue province

Van Loi Bui — 2024-06-27

Brachiaria humidicola is a new grass grown for cattle feed. In this study, experiments were conducted in Thua Thien Hue province, including four treatments with four planting densities of 10 x 10 cm, 20 x 20 cm, 30 x 30 cm, and 40 x 40 cm through three regenerations. The first regeneration was 60 days old, and the next two regenerations were 40 days each from the previous harvests. The experiment aimed to evaluate the effect of planting densities and regenerations on the growth and yield of B. humidicola. The results showed that the tree height, grass bed height, and number of branches/tussock varied significantly between planting densities (p < 0.05), with the highest values observed at the planting density of 30 x 30 cm (96.33 cm, 73.38 cm and 40.17 branches/tussock, respectively). The fresh matter yield, dry matter yield, and protein yield of B. humidicola also showed significant differences (p < 0.05), achieving the highest values at the planting density of 30 x 30 cm (13.87, 3.69 and 0.97 tons/ha/generation, respectively). In general, the best growth and yield of B. humidicola were maximized through regenerations at the planting densities of 30 x 30 cm.

Records of birds in Quang Nam Chau proposed Species and Habitat conservation area, Quang Ninh province, northeastern Vietnam

Trung Thanh Hoang — 2024-06-27

Quang Nam Chau is a proposed species and habitat conservation area located in Quang Ninh province, northeastern Vietnam. The area is covered by primary forest and plays an important role in watershed protection. However, there has not been any previous ornithological study conducted in the area. This study was carried out in October and November 2021 to investigate the diversity of bird species and identify the current threats to avifauna and biodiversity in Quang Nam Chau. A total of 121 bird species belonging to 47 families and 17 orders were identified, with Passeriformes (73 species, 60.3%) and Muscicapidae (11 species, RDi = 9.09) being the most diverse order and family, respectively. Five of the 121 recorded species were globally threatened, and 29 were nationally rare and/or threatened. The avifauna and general biodiversity of the region are threatened by illegal hunting and trapping, agriculture expansion, grazing, and non-timber resource exploitation.

Optimizing conditions to improve polyphenol content and screening antioxidant capacity with DNA protection activity of Perilla frutescens

Ngoc Thien Kim Nguyen — 2024-06-27

Polyphenols are among the natural antioxidants that have been exploited in recent years for their safe and effective ability against oxidative stress. This project aimed to optimize 3 factor-conditions affecting total polyphenols extracted from Perilla frutescens (L.) Britt as well as DNA protection activity of polyphenols for applications in the fields of dietary supplements, pharmaceuticals, and health care. All extracts contained phenolic compounds and exhibited good antioxidant ability through a ferric reducing antioxidant power assay. The total polyphenolic compounds varied from 6.056 ± 0.08 to 9.630 ± 0.127 mg of gallic acid equivalents (GAE) per 1 g dry weight (dw). The highest phenolic content yield was extracted at 70°C for 60 minutes at a pH of 7.0. However, a sample with the highest polyphenol content had a lower residual DNA concentration than the extract (55°C, 60 min, and pH 6.0) with the greatest reducing power. The result of the DNA protection assay also indicated that the extraction concentration and pH condition had a significant effect on preventing DNA from being damaged by free radicals. The study found the conditions for improving polyphenol in the extraction of P. frutescens (L.) Britt with the aid of Box-Behnken Design. This research also proposed that P. frutescens (L.) Britt is a good source showing DNA protection and antioxidant activity for healthcare.

An Efficient Transmission Power Design for SWIPT Multi-antenna Network Integrated by an Intelligent Reflecting Surface

Pham Viet Tuan — 2024-06-27

In this work, intelligent reflecting surface (IRS) is integrated to improve the transmission power in the simultaneous wireless information and power transfer (SWIPT) system with hybrid time-switching (TS) users. The considered scenario includes one base station (BS), one IRS, and multiple TS users, where the BS transmits the information and energy signals to the receivers with IRS assistance. The sum transmission power minimization problem is formulated under the quality-of-service constraints of data rate and energy harvesting amount at the TS users and the equal time-switching periods. The successive convex approximation and alternating optimization methods are exploited to construct efficient algorithms for finding the suboptimal precoding beamforming vectors at the BS and the phase shifts at the IRS elements. Finally, the numerical results show convergence and significant improvement in performance as compared to conventional baseline schemes.

Magneto-optical absorption properties of a Weyl semimetal thin film

T. Hoa Le — 2024-06-27

In this study, we investigate the magneto-optical absorption properties of a Weyl semimetal thin film by calculating the magneto-optical absorption coefficients (MOACs) for both intra-band and inter-band transitions. The wave function and energy spectrum were determined using the Hamiltonian minimal model in the presence of magnetic and electric fields. The expressions for the MOACs in both x- and z-directions are obtained using the compact density matrix approach. The numerical results demonstrate that the MOACs are significantly influenced by temperature, carrier concentration, and magnetic and electric fields.

Application of generalized photon-added pair coherent state to quantum teleportation via atom-field entangled channel

Thi Hong Thanh Le — 2024-06-27

In this paper, we introduce a field-atom entangled state that represents the entanglement over time between a two-level atom and a field in a generalized photon-added pair coherent state in the Jaynes-Cummings model. This entangled state is applied for quantum teleportation of an unknown atomic state from a sender to a receiver that is geographically distant. Accordingly, we use an average fidelity criterion to quantify quantum teleportation processing. The results have shown that the process of teleportation is influenced by parameters such as initial field strength, the amplitude of a state to be teleported, and the number of added photons to two modes of the field. In addition, we also compare the success of teleportation in two cases of the field: the pair coherent state and the generalized photon-added pair coherent state.

In vitro antioxidant activity and content of bioactive compounds from Homalomena occulta

Trang Le Thuy — 2024-06-27

Homalomena occulta, a plant widely used in traditional Vietnamese medicine, was assessed for its antioxidant potential through DPPH radical scavenging and total antioxidant capacity methods. The results showed that Homalomena occulta exhibited significant antioxidant activities with a low IC₅₀ value of 40.27 μg/mL, which is comparable to that of curcumin (38.50 μg/mL). Furthermore, the total antioxidant capacity of the Homalomena occulta extract was determined to be 77.48 ± 2.34 mg GA/g. To investigate the composition of the plant, various compounds including total phenolic, total flavonoid, polysaccharides, and triterpenoids were quantified using colorimetric methods with specific reagents. The content of phenolic compounds, flavonoid compounds, polysaccharides, and triterpenoids in Homalomena occulta was found to be 36.87 ± 0.42 GAE/g, 26.83 ± 0.29 mg QUE/g, 5.06 ± 0.06%, and 52.09 ± 1.77 mg Olenanoic/g, respectively. Notably, this study provides the first-ever report on the polysaccharide and total triterpenoid content of Homalomena occulta.

UHPLC-UV method validation for simultaneous quantification of vitexin and isovitexin from Santalum album L. leaves

Thi Kim Phung Phan — 2024-06-27

Santalum album L. is a precious medicinal herb with high economic value and has been extensively cultivated in Vietnam in recent years. Studies have revealed that the leaves contain two main active ingredients vitexin and isovitexin, which have demonstrated significant potential in treating diabetes, cancer, and inflammation. To contribute to the standardization of the title medicinal herb and its formula, a simple, fast precise and selective method for the simultaneous quantification of vitexin and isovitexin using ultra-performance liquid chromatography (UHPLC) has been developed and validated. The quantification procedure was performed on a Hypersil GOLD aQ Column (3 μm; 150 × 2.1 mm) at 35°C, with a mobile phase of acetonitrile (A) and and water with 0.1% formic acid (B), a flow rate of 0.3 mL/min, a detection wavelength of 336 nm, and an injection volume of 3 µL. The gradient program was set to 0.0-15.0 minutes, transitioning from 5% to 35% A, and 15.0-20.0 minutes, transitioning from 35% to 5% A. Validation of the quantification procedure, following ICH Q2 (R2) guidelines, demonstrated that the method achieved specificity, accuracy, precision, and linearity, with a high correlation between the peak area and the concentrations of vitexin and isovitexin (R² values of 0.9998, respectively). Thus, the developed method can be utilized to determine the content of vitexin and isovitexin in Santalum album L. leaves, contributing to the standardization of medicinal herbs.

Fabrication and evaluation of some electrochemical properties of screen-printed electrodes for use in electrochemical analysis

Thai Long Hoang — 2024-06-27

Three types of conductive inks, including Ceres, Acheson carbon inks, and Ag/AgCl ink, were utilized to fabricate screen-printed electrodes (SPEs) on a 0.4 mm thick polyethylene terephthalate substrate using a screen-printing technique. To enhance the electrical conductivity, the printed electrodes were cured at 80°C for 90 minutes. The basic electrochemical properties of the self-made SPEs using these conductive inks were determined, evaluated, and compared with commercial SPEs from Metrohm. Although the electroactive surface areas of the self-made SPEs were not significantly different from those of the commercial SPEs, the heterogeneous electron transfer rates on the surfaces of self-made SPEs using Ceres and Acheson inks were inferior to those of the commercial SPEs. However, after pre-condition by applying a potential of +1.2 V for 180 s in a 2 M Na₂CO₃ solution, the electrochemical properties of the self-made SPEs, including the active surface areas and heterogeneous electron transfer rates, were significantly improved and became better than those of the commercial SPEs.

Study on the antifungal potential of Piper betle methanol extract against Colletotrichum gloeosporioides cutinase

Nhung Nguyen Thi Ai — 2024-06-27

Piper betle methanol extract and its compositional characteristics had been evidenced for their effective inhibitability against rice-blast fungus. In this work, they were subjected for further computational efforts to complete their bio-chemo-pharmacological profile, and broaden their anti-fungal potentiality against Colletotrichum gloeosporioides cutinase presentative (PDB-3DEA). As the results, the most noticeable promising inhibitors particularly regard to 5 (DS -10.8 kcal.mol^-1; ground-state energy -499.50 a.u.; dipole moment 2.61 Debye; no toxicity; content 49.90 %) and 6 (DS -10.9 kcal.mol^-1; ground-state energy -652.15 a.u.; dipole moment 2.82 Debye; no toxicity; content 13.23 %), given by both their natural contents and predicted properties. The theoretical retrievals would reinforce the antifungal activities of P. betle and be conducive to further efforts to develop a green fungicidal alternative with broad-spectrum and cost-effective pesticidal advantages.

Hilbert coefficients of ideals under perturbation of an ideal

Cao Huy Linh — 2024-06-27

Let (R, m) be a noetherian local ring, J an m-primary ideal of R and
I = (f1, ..., fr) an ideal generated by a filter regular sequence f1, ..., fr of R. In this
paper, we will prove the preserve of Hilbert coefficients of R/I with respect to J
under J-adic perturbation of I, provided that J is a parameter ideal generated by a
d-sequence of R/(f1, ..., fi) for i = 1, ..., r.