CTU Journal of Innovation and Sustainable Development

Short time changes of zooplankton communities in Cam Ranh Bay

Tam Vinh Nguyen — 2025-11-28

Coastal embayments are ecologically significant ecosystems increasingly affected by human activities and climate change pressures. This study investigated the spatial and temporal dynamics of the zooplankton community in Cam Ranh Bay under varying environmental conditions by chronically sampling in consecutive days, weeks and seasons. The bay exhibited high zooplankton diversity, with 188 species recorded across seven phyla. Arthropoda, particularly Copepoda, contributed over 65% of the total species richness. Notable changes were observed in the zooplankton community, particularly within Copepoda families, even over short periods (e.g., day or week). At a seasonal scale, the zooplankton community shifted with increased densities of larval groups during the rainy season, coinciding with a relative decrease in arthropods. Biodiversity indices indicated greater stability during the rainy season, while canonical correspondence analysis (CCA) revealed distinct seasonal relationships between species and environmental variables, such as nutrient fluxes and salinity. These findings underscore the ecological complexity of Cam Ranh Bay, providing a critical baseline for monitoring environmental changes and managing human impacts on this biodiverse ecosystem.

Morphological and anatomical characteristics of Ludwigia species (Onagraceae) in Can Tho city

Huynh Nhat Anh Bui — 2025-11-28

This study was conducted to provide information on the morphological characteristics and anatomical structures of species belonging to the genus Ludwigia, serving as a scientific basis for the taxonomical classification of this genus for more effective exploitation and utilization of plant resources in Can Tho City. In this study, plant samples were collected, morphological characteristics were described, anatomical structures were examined, and specimens were prepared for observation and photography under an optical microscope. The results showed that L. adscendens differs from other species in the genus Ludwigia by having a stem with spongy roots, white flowers, and abundant spongy parenchyma in the anatomical structure of its stem and leaves. The remaining four species are distinguished by the morphological characteristics of the stem (angled, branched, with or without trichomes), leaves (shape, presence or absence of trichomes), flowers (shape of petals and sepals, number of stamens), and fruit (shape, presence or absence of angles, color). Anatomically, the species can be differentiated by the shape of the stem and fruit cross-sections, while the tissue structure and arrangement in the stem and leaves are quite similar.

Isolation and characterization of Vietnamese medicinal plant (Nhân trần tía, Adenosma bracteosum Bonati) bacterial endophytes displaying in vitro antagonistic activities

Thanh Dung Nguyen — 2025-11-28

In both traditional and modern Vietnamese medicine, Adenosma bracteosum Bonati is employed for the treatment of hepatitis, lung ailments, and liver disorders. Bacteria that reside within the cells of medicinal plants, use unique strategies to enhance the growth and survival of their host plants, often through distinctive secondary metabolites, are known as symbiotic or endophytic bacteria. In this study, the objective was to find bacterial endophytes with antibacterial properties. Fifty-eight endophytic isolates were obtained from the wild medicinal plant A. bracteosum. They were assessed for their in vitro antibacterial activities against common pathogenic bacteria, including Escherichia coli, Staphylococcus aureus, Aeromonas hydrophila, Vibrio parahaemolyticus, and Dickeya dadantii. Twelve isolates with broad antibacterial activity produced siderophores and lytic enzymes, with SB1R13.2 showing the greatest resistance against all five pathogenic bacterial strains, producing siderophores and synthesizing digestive enzymes. According to the 16S rDNA sequences, the SB1R13.2, SB4R5, and SB5T2 isolates demonstrated the most similar genetic affinity to Bacillus velezensis. Meanwhile, the SB4R2 isolate exhibits genetic similarity to Burkholderia sp. These findings suggest that this specific species, with its broad-spectrum antibacterial properties, holds significant potential as a promising agent for biological control and the treatment of diseases in humans and other organisms.

Selection, identification, and application in yogurt fermentation of lactic acid bacteria isolated from guava (Psidium guajava L.) fruits

Ngoc Thanh Tam Huynh — 2025-11-28

Lactic acid bacteria (LAB) can be isolated from different natural sources such as plants, fruits, or vegetables. The organic acid-producing capacity and antibacterial activity of each LAB strain are highly dependent on its isolation source. In the study, LAB strains were isolated from guava (Psidium guajava L.), identified for organic acid production and antibacterial activity. Twenty LAB isolates showed rod, oval, or cocci shape, Gram-positive, catalase-negative, oxidase-negative, the ability to degrade CaCO₃, and could not produce indole from tryptophan. Especially, the strain TN2 produced the highest organic acid content (8.7±0.14 g/L) as well as exhibited the strongest antibacterial activity against Escherichia coli (E. coli) with the inhibition zone diameter of 12.33±2.08 mm. The bacteria strain TN2 was applied to ferment yogurt with 8% guava juice, at a milk and condensed milk ratio of 2:1, giving the best lactic acid content and sensory evaluation. The strain TN2 was identified as Lactococcus lactis strain according to the 16S rRNA gene sequence analysis and registered on GenBank with code number MN860000.1. This strain can be a potent alternative to commercialized LAB strains in fermented food products.

Adaptive inner-loop pressure regulation using an RBF-tuned PID for position accuracy and disturbance rejection in PAM systems

Vinh-Phuc Tran — 2025-11-28

This study investigates the impact of inner-loop pressure regulation on the dynamic performance of pneumatic artificial muscle (PAM) systems using a dual-loop control architecture. Three pressure control strategies – Proportional-Integral (PI), Proportional-Integral-Derivative (PID), and Radial Basis Function neural network-tuned PID (RBF-PID) – are experimentally evaluated in terms of tracking accuracy, transient response, and disturbance rejection. Results show that the RBF-PID controller achieves the highest accuracy of pressure tracking , with a root-mean-square error (RMSE) of 0.067 bar under a modulated sinusoidal input, outperforming PID (0.088 bar) and PI (0.094 bar) controllers. In position control tasks, all dual-loop configurations offer improved stability compared to the single-loop setup. The RBF-PID controller further enhances performance, achieving a settling time of 3.04 seconds, zero overshoot, and the shortest recovery time of 2.73 seconds under a 10-kg load disturbance. Although the performance gap between PI and PID remains modest, suggesting PI remains a practical solution for resource-constrained applications, the RBF-PID controller provides significant benefits in adaptability and robustness. These findings underscore the importance of adaptive pressure regulation in improving the tracking accuracy and resilience of PAM-based actuators. The choice of control strategy should therefore be guided by the specific application context, balancing control performance with computational and hardware constraints.

Elastic modulus of reinforced concrete from bending test

TrustGod John — 2025-11-28

This study demonstrates an experimental approach for direct measurement of RC elastic modulus. This work considered the transformed moment of inertia as an input variable. The planned laboratory study involves subjecting reinforced concrete beams with varying reinforcement ratios from 0.43% to 1.77% and grades of concrete (M7.5, M10, M15, M20) to bending tests. Two equations for elastic modulus determination were developed based on beam theory. The first crack load and the corresponding deflection were measured from the load-deflection curve. The uncracked transformed moment of inertia (I_un,tr), cracking moment (M_cr), and deflection ( at first crack were computed. By substituting the M_cr, and Iun, tr into the deflection equation based on the test setup, the elastic modulus (E) of RC was determined. Results showed that as the concrete grade increases, so does its modulus of elasticity, and it demonstrated a direct correlation between the increase in concrete grade and its modulus of elasticity. It was also observed that as the percentage of reinforcement increases, the elastic modulus of RC increases due to increased flexural stiffness. The derived equations were able to accurately compute the elastic modulus capturing the composite behavior of concrete and reinforcement.

Understanding learner satisfaction in EFL Continuing Education Programs: A Qualitative case study in Viet Nam

Xuan Mai Le — 2025-11-28

This qualitative case study explores the factors contributing to learner satisfaction in English as a foreign language (EFL) continuing education programs in Viet Nam. Grounded in the andragogical principles and the socio-cultural perspective on language learning, the study investigates the experiences of five Vietnamese adult learners, including three graduates and two current participants, through semi-structured interviews. The findings reveal that learner satisfaction is shaped by four key factors: teacher-student relationships, program relevance to learners’ goals, challenges and support mechanisms, and cultural dimensions of satisfaction. Participants emphasized the importance of empathetic, supportive teachers, practical and goal-oriented curricula, and flexible program structures that accommodate their professional and personal responsibilities. Cultural values, such as respect for teachers and the inclusion of culturally relevant content, further enhanced their engagement and motivation. The study’s contributions lie in contextualizing learner satisfaction within the Vietnamese socio-cultural framework, highlighting the interplay between universal adult learning principles and local cultural practices. Practical implications include the need for culturally responsive pedagogy, flexible program design, and robust institutional support to enhance EFL learning experiences. While limited by its small sample size, this study offers valuable insights and lays the groundwork for further research on adult learner satisfaction in EFL programs across diverse contexts.

Exploring themes and patterns in periodic examination in English language classes

Nikko Suico — 2025-11-28

Assessment practices need to be transformed to fulfill their guiding role effectively in the teaching and learning process. This study explores the structure, content, and educational value of district-wide, standardized English assessments for grades 7–10 through the Bloom’s Taxonomy framework. Using inductive qualitative content analysis, themes, building techniques, content distribution, curriculum alignment, and learning implications were highlighted in this study. The results show a progression in the skills evaluated, prioritizing communication and critical thinking over basic grammar. To ensure fair and equitable assessment, areas for test construction improvement are also noted, focusing on minimizing bias, maintaining consistency, and ensuring clarity. The distribution of content and the significance of a well-rounded strategy are also examined in the analysis. Although the emphasis is on analytical skills, the lack of attention to evaluation asks raises questions about inclusivity. Closing this gap will guarantee that tests fully evaluate a variety of cognitive skills. Likewise, teachers can create a dynamic, inclusive learning environment that fosters critical thinking, communication, and analytical skills through the improvement of assessment practices.

Ruling the wild waves: Construct of learning strategies in Physics among college students

Donabelle Apa — 2025-11-28

Physics is known to be the most difficult branch among all other sciences. Understanding how students approach and engage with learning in physics can aid in determining effective strategies that result in better learning outcomes. Teachers can uncover best practices and assist struggling students in learning physics. The strategies in learning physics will ultimately improve the knowledge and performance of the struggling students. This quantitative study captures the construct of learning strategies in physics among college students. To achieve the purpose, an exploratory factor analysis was utilized, employing purposive sampling to collect qualitative data involving 6 participants to extract their learning strategies. From these statements, the researchers were able to generate a survey questionnaire that was used in the quantitative phase with the application of random sampling. When employing exploratory factor analysis, with a KMO of .851. The students' overall perception of these strategies was also measured as moderate. Hence, future researchers may consider the result of the study for further investigation utilizing confirmatory factor analysis, and structural equation modeling, and determine a model that best fits learning strategies in physics.

“Serious Game” dialogue tool for groundwater extraction in Ben Tre and Soc Trang provinces

Luyen Phuong Doan Nguyen — 2025-11-28

Groundwater resource in the Vietnamese Mekong Delta (VMD) face over-exploitation activities, which leads to subsidence and salinity intrusion. Several efforts to limit groundwater exploitation have been made, existing limitations. Therefore, groundwater stakeholders’ meetings are conducted to discuss deeply management and usage problems at the local level in a general forum. The "Serious Game" discussion tool simulates scenarios addressing groundwater issues and facilitates active participation and dialogue among diverse stakeholders, including policymakers, water supply units, and water users. Through rounds of “Serious Game”, participants directly observed the effects of over-exploitation of groundwater, such as subsidence and salinity intrusion, to decide on choosing irrigation-used water. The main approach is to assess participants’ consideration of groundwater management strategies for their farming activities. Research results showed that the amount of water demand in Soc Trang and Ben Tre provinces had a downward trend, which indicates changes in insights into groundwater sustainable usage. They learned how to negotiate water demands among different zones to reduce water units. Feedback from players and stakeholders contributes to the completion of the “Serious Game”. This tool is recommended for use in public awareness campaigns and community events to raise awareness of groundwater issues for local water users.

Determinants of publication output: Analyzing WoS journal contributions by university lecturers in Viet Nam

Thi Phuong Anh Doan — 2025-11-28

This study examines the factors determining research output in Viet Nam, particularly the publication of Web of Science (WoS) listed journals, which affects the global ranking of Vietnamese universities. We analyzed the academic profiles of 2,042 faculty members from the top 12 universities, as ranked by Webometrics in 2021, using a nonlinear Poisson regression model. The analysis identified eight key factors influencing publication count: age, gender, field of study, academic degree, academic rank, professional title, administrative position, and educational background. Among them, productivity follows an inverted U-shaped pattern with age, increases with a PhD degree and foreign education, and is higher among male researchers and those in natural sciences. In contrast, administrative roles are associated with fewer publications, likely due to shifting priorities and increased non-research responsibilities. The academic rank of associate professors is related to higher research outputs, while the academic rank of full professors and professional titles shows little evidence of correlation to research outputs. The findings emphasize the diverse factors influencing academic research output. Based on these findings, we propose recommendations to boost international publication productivity in Vietnamese universities.

Gill remodeling responses of the clown knifefish (Chitala ornata) to temperature and hypoxic stress

Diem Tuong Dang — 2025-11-28

Gill remodeling ability of clown knifefish exposed to different temperature levels (27°C and 33°C) and dissolved oxygen levels (hypoxia - 25% and 30% air saturation (at 27°C and 33°C), and normoxia - 95% air saturation) were performed applying vertical section to estimate lamellar surface area (SA), gill filament volume, lamellar volume, harmonic mean water blood thickness and calculate anatomic diffusion factor (ADF). The initial lamellar SA and harmonic mean water blood thickness of Chitala (33.12 ± 1.09 g) were 51.43 ± 3.10 mm²g^-1and 3.59 ± 0.15 µm in normoxia, respectively. The lamellae SA increased strongly after one month of exposure to elevated temperature and hypoxia. A significant reduction in the harmonic mean water–blood barrier thickness was observed following one month of hypoxia, whereas temperature effects were observed significantly after two months. The value of lamellar SA in the hypoxic group at 33°C (47.02 ± 2.44 mm²g^-1) was twice as high as that of the normoxic group at 27°C (22.38 ± 1.06 mm²g^-1) while the ADF in the hypoxic group at 33°C was nearly 4-fold higher than the normoxic group at 27°C. Findings in Chitala suggest that gill remodeling represents an ancient adaptation that has existed for over 300 million years.

Investigation of Bacterial Infections in Farmed Mud Crab (Scylla paramamosain) in Ca Mau Province, Viet Nam

Thi My Duyen Tran — 2025-11-28

This study aimed to identify the bacterial pathogens associated with abnormal symptoms in farmed mud crabs (Scylla paramamosain) in Ca Mau province. There were 161 isolates of bacteria obtained from blood, hepatopancreas and muscle of 202 collected mud crabs using TCBS and TSA medium supplemented 1.5% NaCl. A total of 11 representative isolates based on morphological features were identified using 16S rRNA sequencing. There were six different species including Vibrio parahaemolyticus, Vibrio alginolyticus, Vibrio harveyi, Photobacterium damselae, Shewanella algae and Staphylococcus saprophyticus were identified, in which Vibrio spp. were the most dominant (63,63%). These bacterial species, except S. algae, have been documented as causative agents of bacterial diseases in mud crabs. Furthermore, the phylogenetic analysis indicated that Vibrio species isolated in the present study were closely related to each other as well as the minimal difference between isolates and other selected reference strains.

Factors influencing the effectiveness of academic advising by lecturers at Can Tho University

Thi Thanh Huong Huynh — 2025-11-28

The study was conducted to find out the factors affecting the effectiveness of academic advising work of lecturers at Can Tho University (CTU) from the perspective of students. The study used a questionnaire survey method with 124 students studying at CTU according to the convenience sampling method. In this study, exploratory factor analysis (EFA) and factor score matrix analysis were used to find factors that affect the effectiveness of teachers' administrative work at the school. Results from exploratory factor analysis from a survey of 124 students at Can Tho University show that there are five factors affecting the effectiveness of academic advisor activities at CTU, specifically: Academic advisor, Relationship natural and social relationships, Students, Schools and Other factors.

Youth Union work and Sustainable Development: Case study of the Summer Volunteer Program “Em Hoi Nhap”

Thi Thuy Linh Nguyen — 2025-11-28

This article examines the importance of the Youth Union’s efforts in encouraging the sustainable development of educational institutions, with a particular focus on the summer volunteer program “Em hoi nhap” involving students from the School of Foreign Languages. Qualitative research was conducted with nine participants who were program volunteers, using semi-structured interviews, to study the effects of The Youth Union activities on the formation of soft skills and social awareness, and students‘ ability to integrate into society. The research also evaluated the contributions of the Youth Union’s work to sustainable development in the higher education environment in general and Can Tho University in particular.