Our country has suitable climatic conditions for growing mango trees. This is a fruit tree that brings economic value to farmers. Therefore, identifying diseases in the flower during the flowering and fruiting stages is very important, greatly affecting to productivity of the season. Therefore, a program on smartphones to identify diseases in mango flowers through images of mango flowers is very necessary. The research used a set of data of 4 types of mango flowers: anthracnose mango flowers, burnt mango flowers (black spot disease), choked mango flowers, and disease-free mango flowers, with 733 images collected. The research already used deep transfer learning techniques to jog the training on model EfficientNetB0 and model MobileNetV2. As a result, the accuracy of the EfficientNetB0 model reached 99.84%, higher than the MobileNetV2 model, which only reached 95.21%. The results of the research can help agronomists and researchers have solutions to support farmers and guide the treatment of disease-carrying mango flowers appropriately and effectively.

In the mechanical manufacturing industry, surface roughness after machining is one of the crucial technical requirements. The evaluation has traditionally been carried out on complex probing systems by technicians, which has led to some difficulties in the assessment process. In this study, we propose the use of the convolutional neural network AlexNet to automate the identification and analysis of surface roughness. First, we collected images of metal surfaces with pre-evaluated roughness values Ra ranging from 0.4 to 3.2 μm. Next, AlexNet was trained on this dataset to learn to recognize different levels of roughness. Experimental results with an accuracy of 89.2% have demonstrated that the AlexNet model achieved significant roughness identification performance. The research has proven the feasibility and effectiveness of applying convolutional neural networks to automate the surface quality assessment process.

Object detection models based on convolutional neural networks are continuously evolving and widely applied in various domains, especially in intelligent transportation systems. In this study, the authors applied deep learning techniques, particularly real-time vehicle detection models: based on anchor-box (for example, You Only Look Once - YOLO), based on keypoint (for example CenterNet), and based on Transformers (for example, Detection Transformers - DETR) for detection vehicles. These models were fine-tuned and trained using transfer learning techniques to enhance vehicle detection capabilities. The results of the experiments indicated that the YOLO model achieved the highest accuracy (98.3%) with 11.7 ms time of detection. Meanwhile, the DETR model had the fastest execution time (2.3 ms) but the lowest accuracy (62.4%). The CenterNet model proved to be the best choice (94.11% - 8 ms) as it struck a balance between accuracy and execution time, making it suitable for real-time applications.

This study aimed to select suitable carrier for store sodium tripolyphosphate absorbing Comamonas sp. PAN1.12 isolated from water samples collected at a seafood processing wastewater treatment system. Eleven carriers including bagasse, coffee grounds, talc, bran, straw, and sawdust as well as a mixture of each of the five carriers with talc (1:1) were used for bacterial preservation. Talc and sawdust mixed with talc amended with 1% carboxymethyl cellulose, 1.5% CaCO3, and 100×106 CFU/g of inoculated bacteria were able to maintain the density (>106 CFU/g) and the sodium tripolyphosphate absorbing capacity (approximately 67%) of Comamonas sp. PAN1.12 after one-month storage. The concentration of carboxymethyl cellulose amendment and the density of inoculated bacteria influenced the bacterial density but did not affect the sodium tripolyphosphate absorbing capacity of PAN1.12.

Benzimidazole and their derivatives are known as important frameworks in the pharmaceutical, dye, agrochemical, and materials industries. Therefore, the development of an efficient synthetic method to obtain the benzimidazole heterocycle has always been of interest to scientists, especially focusing on green organic synthesis. In this study, the synthetic method of benzimidazole derivatives under solvent-free conditions was successfully developed. This method is highlighted by solvent-free reaction conditions and short reaction time with the use of Na2S2O5 as an inexpensive and environmentally friendly oxidizing agent. Applying the above procedure, ten benzimidazole derivatives were successfully synthesized in rather good yields (51-85%).

Gluconic acid is applied in construction, food technology, pharmaceutical products, etc. Many studies indicated that microorganisms were potential candidates for the production of gluconic acid from glucose. This study aimed at the isolation of indigenous bacteria that can transform glucose to gluconic acid. Twenty-five bacterial strains capable of utilizing glucose were isolated from different fruit peels. Three strains GAB3, GBN6, and GSF5 were able to effectively convert glucose (100g/L) to gluconic acid in a minimal medium with pH ranging from 5 to 8 after 5 days of inoculation. Strain GSF5 producing 29.19 g/L showed the highest gluconic acid synthesis ability in the medium at pH6 and was identified as Staphylococcus sp. GSF5 based on 16S-rRNA gene sequence analysis and alignment.

Sulfides are naturally formed by bacteria capable of decomposing sulfur-containing organic compounds or sulfate-reducing bacteria. Seafood processing wastewater contains sulfide in the form of H2S, if untreated, it can affect the water environment, aquatic organisms, and public health. From wastewater samples collected at the seafood processing plants, 15 bacterial strains capable of absorbing sulfide were isolated and examined for their ability to absorb sulfide in the minimal medium supplemented with sulfide at concentrations of 40, 80, and 160 mg/L after 24 hours of incubation. Strain SIN4.2 performed the most effective absorption of sulfide at 3 concentrations and was identified as Pseudomonas sp. SIN4.2 based on 16S-rRNA gene sequence analysis.

From the roots of Cocos nucifera L. collected in Cai Rang district, Can Tho city, through column chromatography, 6 compounds were isolated and identified: daucosterol, β-sitosterol, p-hydroxybenzoic acid, ethyl protocatechuate, diosgenin, and trans-resveratrol from the ethyl acetate extract. The chemical structures of the compounds were determined based on analysis of HR-ESI-MS, 1D- and 2D-NMR spectral data as well as comparison with published spectral data from previous studies.

Stage-structured models consider development processes which are divided by different developmental stages. These models are common statistical models in disease progressions and biological development of plants and animals. A Bayesian approach based on deterministic transformations in the Metropolis-Hastings algorithm is considered the most accurate estimate to estimate parameters for these stage-structured models. The main purpose of this paper is to evaluate the appropriate sample size for the given stage-structured model by applying the Bayesian approach to estimate parameters. The results of the proposed sample size assessment method are very useful in finding out the sample size at each sampling time and the appropriate number of sampling times for designing experiments. The results of this sample size assessment are also applied to COVID-19 incubation period data. This study on the COVID-19 incubation period is a continuation of previous studies and has implications for pandemic prevention.

Histone deacetylase (HDAC) is a significant target in cancer therapy. In this work, the dataset of 32 metal-chelating compounds was designed based on the chalcone-sulfonamide scaffold. Molecular docking was conducted on HDAC class I family members. The results revealed robust interactions of these compounds with key amino acids at the active site, all displaying binding energies lower than -15 kJ/mol. Notably, derivative 20, a 2'-hydroxychalcone-sulfonamide compound bearing a meta-NO2 substituent, exhibited the most promising efficacy across all selected HDAC enzymes. This compound holds great potential for synthetic and biological evaluations in the future.

Seafood processing wastewater contains many organic compounds. The decomposing of these substances forms amines and ammonia resulting in odors that affect public health. In aquatic environments, ammonia is converted into ammonium which is used by bacteria for growth. This research aimed at the isolation of indigenous bacterial strains from seafood processing wastewater capable of absorbing ammonium. From 4 water samples taken from a seafood processing wastewater treatment system, 24 bacterial strains able to uptake ammonium were isolated. Our data showed that strain WY3.3 was the potential candidate for ammonium (200 ppm) absorption with an efficiency of 94.6% at 24 hours of incubation. Aeration and neutral pH (pH=7) were optimal conditions for ammonium uptake with efficiencies of 91.9% and 91.7%, respectively. The culture medium was supplemented with NaCl at 1% and 2%, strain WY3.3 was still able to absorb 99.1% and 97% ammonium. Based on 16S-rRNA gene sequence analysis, strain WY3.3 showed 99.44% sequence similarity with Bacillus funiculus and was identified as Bacillus sp. WY3.3.

The study’s objective was to determine proper additive concentrations in the washing solution for preserving Nam Roi pomelo, ensuring adherence to quality standards, and prioritizing consumer health and safety. Three additives—NaHCO3 (1%, 2%, 3%, 4%), citric acid (1%, 2%, 3%, 4%), and NaCl (8%, 10%, 12%, 14%)—were separately added to the solution. Results showed the effectiveness of NaHCO3 and citric acid addition during storage. A 3% NaHCO3 concentration indicated that Nam Roi pomelo had less green color loss and mass loss than 3% citric acid addition. However, the treatment with 3% citric acid was more effective against total aerobic microorganisms, yeasts, and molds. Besides, the use of 12% NaCl contributed to color stabilization, reduced weight loss, and inhibited microbial growth.

The scientific name of Xao tam phan plant is Paramignya trimera (Oliv.) Guillaum, a traditional Vietnamese medicinal plant that has been used in the treatment of many dangerous diseases such as liver, lung, and cervical cancer. This study evaluated the influence of 5 types of packaging materials (PE, PA, PP, LDPE, HDPE) on physicochemical properties, bioactive compounds and antioxidant activity of fresh medicinal plant Xao tam phan during storage at room condition. The results showed that preservation of fresh Xao tam phan plant by PA packaging for 4 days at room condition achieved low resperation rate of -9.86 mL O2/kg/h, least weight loss of 0.40% and color difference of 8.27, maximum bioactive levels including total saponin content of 130.51 mg EE/g dry sample, total phenolic content of 10.20 mg GAE/g dry sample, and total flavonoid content of 169.36 mg CE/g dry sample, as well as greatest antioxidant activity comprising DPPH radical scavenging capacity of 4.18 mg TE/g dry sample, ferric reducing antioxidant power of 4.99 mg TE/g dry sample, and cupric reducing antioxidan capacity of 13.61 mg TE/g dry sample. Based on obtained results, PA packaging is proposed to preserve fresh Xao tam phan plant for further utilization and investigation.

To improve the recovery yield of dietary fiber obtained from da xanh pomelo (Citrus maxima (Burm.) Merr.), the study was conducted to evaluate the pretreatment process with ethanol 96o on the efficiency of fiber enrichment, expressed in terms of total dietary fiber (TDF), soluble dietary fiber (SDF) and insoluble dietary fiber (IDF) content. The investigated conditions consisted of (i) soaking time (10 - 25 minutes), (ii) soaking temperature (50 - 78.3oC), (iii) materials/ethanol ratio (1/1.25 - 1/5 g/mL) and drying temperature (50 - 70oC). Thereby, pretreatment revealed a greater efficiency of 15.02%, and 49.04 % at TDF, and SDF content than those without pretreatment. The results of the investigation of pretreatment conditions of pomelo’s albedo with ethanol 96o illustrated that soaking overnight (12 hours) at room temperature (30oC) and raw materialethanol ratio of 1:2.5 g/mL followed by drying at 70oC in 5 hours reached the highest level of IDF (42.39 ± 0.10%), TDF (74.68 ± 0.56%) and SDF (32.29 ± 0.54%).

The symbiotic relationship between root fungi and plant roots plays an important role in the absorption of water and nutrients of plants. The study was conducted to investigate the presence and distribution of orchid mycorrhizal fungi (OMF) in the roots and growing medium of three species of orchid including Dendrobium sp., Phalaenopsis sp., and Cymbidium sp. grown on sphagnum moss, charcoal, and pine substrates in 10 orchid gardens in Thu Duc city, Ho Chi Minh city. The symbiotic fungi in the root samples were stained with trypan blue, and the spores in the media were isolated by the wet sieving and decanting technique and stained with Melzer + PVLG to observe the spore morphology. The results showed that in the roots and the substrate, there was the presence of 3 fungal genera, including Glomus, Acaulospora, and Septoglomus. In addition, 2 spore types of Dr1, and Dr2 in the roots and Ki4 spores in the growing medium were recorded. Glomus was the predominant genus in orchid roots. Meanwhile, Acaulospora was the most commonly present genus in orchid growing media with an average total spore density of 188 spores/g of growing medium.

The study was conducted to survey the current status of cultivation and evaluate some soil biological and chemical characteristics of organic and conventional coconut farms in four districts belonging to Ben Tre province. The parameters of cultivation techniques inclduing soil pH, EC, the density of soil microorganisms, and dehydrogenase enzyme activity in the soil were collected. The results showed that most farmers had rich experience, varying from 10 to 70 years. Although most farmers (59.5%) have converted to organic coconut farming system from conventional one, a part of them still use chemical fertilizers and pesticides on their farms, causing ecological imbalance. The results also showed that applying organic fertilizer regularly to coconut farm soils helped to increase the dehydrogenase enzyme activity of soil microbes compared to the group of traditionally cultivated gardens.

Yellow-fin goatfish, Mulloidichthys vanicolensis (Valenciennes, 1831) is a widely distributed fish in the Indo-Pacific oceans and is popularly exploited in the Southwest Sea of Vietnam. Contrary to its essential role, there is a lack of studies about the biology of this goatfish species. By analyzing the fisheries biology data of yellow-fin goatfish, the present study indicated some biological characteristics of this commercial species, including the length composition, growth, and reproduction characteristics. The results showed that M. vanicolensis in the Southwest Sea of Vietnam had a positive allometric type of growth (slope b = 3.2). The growth parameters including the asymptotic length (Linf), the growth coefficient (K), and the growth performance index (Ø’) were 184.2 mm, 0.95 year-1, and 4.5, respectively. The fork length at first maturity was 114 mm in males and 116 mm in females. Females dominated the population with a sex ratio of 0.6:1 (M/F). Spawning time was scattered throughout the year, and a higher spawning rate occurred at the beginning of the dry and rainy seasons. In addition, this study showed that yellow-fin goatfish are over-exploited with high pressure (E=0.62).

This study aimed to assess the quality of water supply resources for rice-shrimp farming in Thoi Binh district, Ca Mau province to provide fundamental information for water quality management. Surface water was collected at 6 sites with 4 sampling periods including the beginning and end of the shrimp crop (February/July), the beginning and end of rice crop (October/December) in Bien Bach Dong commune. Results showed that most of the water quality parameters still met the national regulations and are suitable as water supply for aquaculture. However, several parameters such as total suspended solids (TSS), biological oxygen demand (BOD), total nitrogen (TN), and total phosphate (TP) were relatively high as compared to the national technical regulation on surface water quality. High variations of water salinity, especially in inland canals, were observed during the shrimp crop. Nutrients showed an upward trend over the sampling period. It is therefore suggested that regularly monitoring water quality should be done while using water supply resources for the rice-shrimp farms in the survey area.

Experiential learning, in which learners are directly involved in activities, thereby discovering knowledge and building competence, and applying what they have learned in practice, has been proven to be effective. Learning through experiential activities also contributes to innovation in teaching, including the formation and development of learners' competence and qualities in today's high schools. However, how to organize the experiential activities to suit the current context is still an issue that needs attention. Therefore, this study aims to answer the question: Can experiential learning in Literature develop problem-solving competence and creativity for students? In this study, an experiment was conducted in which 1 class of 45 grade 11 students from Vo Van Kiet Middle and High School, Rach Gia City, Kien Giang Province were learned Literature through experiential activities to develop problem-solving competence and creativity. Data was collected through observing students' activities and synthesizing students' portfolios. Research results showed that experiential activities can develop students' creative and problem-solving abilities.

Teaching mathematics to students majoring in Economics has always posed many difficulties, and challenges, and it has been a subject of concern for both the directly teaching instructors and educational researchers. The objective of this article is to identify the existing issues in teaching Advanced Mathematics to students majoring in Economics and propose practical solutions to address these problems. The author employs a method of data collection, combining information and observations during the actual teaching process for students at the National Economics University. The research results reveal that program reduction, non-differentiation of subjects, and the absence of practical teaching methods are the main existing challenges. The article also emphasizes the significance of real-life integrated teaching, incorporating active learning methods, and providing individualized support to help students enhance their learning efficiency.

From the theory of conceptual metaphor, the article initially explores the thinking, culture, and conceptual system of people in Tran Dang Khoa's poetry. Through a survey of 190 poems in “Tran Dang Khoa's Poetry Collection”, the results showed that there were 146/190 poems containing conceptual metaphors about people, accounting for 76.8%, specifically: PEOPLE ARE ENTITIES - NATURAL PHENOMENA, PEOPLE ARE ANIMALS and PEOPLE ARE PLANTS. These metaphors are conventional and are also used in everyday language. The same mechanism for metaphorical thinking in Tran Dang Khoa's poetry is also present in most of the most common Vietnamese notions. These metaphors originate from the mutual effect of the poet in particular as well as the Vietnamese people in general with the outside world, which are the most basic experiences.

The study was conducted to investigate staff and students’ awareness of Can Tho University brand through digital media. Research methods included synthesis, analysis of documents and survey of 440 staff members and 209 students of Can Tho University. The results showed that students and staff members had a high level of awareness of Can Tho University’s brandname, accounting for 81.3% and 70.9%, respectively. However, the awareness of some brand identity’s elements was low, then several solutions for improving the brand identity’s elements were proposed. Moreover, to increase brand awareness, Can Tho University should develop its brand identity, and strengthen brand promotion activities.

This study aimed at analyzing the factors affecting Vietnam's rice export value in the period of 2011-2021. The study employed the gravity model with panel data from 45 rice-imported countries and territories. The estimating methods of Ordinary Least Square (OLS), Fixed Effect Model (FEM), and Random Effect Model (REM) were applied for the model validation. The results showed the factors that have positively impacted exported value were the world export price of rice, the population of imported countries, Comprehensive and Progressive Agreement for Trans-Pacific Partnership (CPTPP) members, and membership of multilateral or bilateral relationships between Vietnam and imported partners. However, the gross domestic product (GDP) of the importing country, the self-produced food output of the importing country, and Vietnam's inflation rate have negatively impacted rice export value. Based on the estimated results of the models and the current situation of Vietnam's exports, several policy implications for increasing Vietnam's rice export value in the coming time were proposed.

The stock market is a highly complex non-linear system, and its volatility is influenced by numerous factors, making stock price prediction a challenging task. Long Short Term Memory networks (LSTM) model, Gated Recurrent Unit (GRU) model, and their hybrids are designed using the Python programming language with available supporting packages, and they demonstrate high accuracy in forecasting. The LSTM-GRU Hybrid model performs the best among the complex models. Through the LSTM-GRU Hybrid model, the study predicts the trend of the VNIndex for the next 100 days, indicating a rising trend. This indirectly suggests a potential resurgence in the Vietnamese stock market, driven by new government policies.

Based on primary data collected from 191 farming households following the crop rotation model of 2 rice crops and 1 sesame crop in 2022 in the Mekong Delta, through the frontier production function and the frontier profit function following the Cobb - Douglas model, technical efficiency and economic efficiency of farming households were estimated. This result shows that with the level of use of existing inputs and techniques, the rice and sesame productivity of farming households has the potential to increase further to achieve maximum productivity and improve technical efficiency. The level of economic efficiency of farming households is also likely to increase if the technical efficiency and allocative efficiency of farming households are optimally improved.