Effects of different nutrient solutions on growth and flower quality of gerbera (Gerbera jamesonii) grown in hydroponic close system

The nutrient solution is the decisive factor for the growth and development of hydroponic plants. This study was conducted to determine the effect of five nutrient solutions, namely, Hoagland, Knop, Hydro Umat F, BKFAST, and Bio-Life, on the growth and development of gerbera (Gerbera jamesonii) in the hydroponic system. The results show that Hydro Umat F is the most suitable solution for planting gerbera in terms of plant height, number of leaves, leaf size, and root volume. In addition, the flower yield of the gerbera plants nourished on Hydro Umat F is also the highest, with 8.7 flowers per plant after five months in the hydroponic system. The flowers have a diameter of 9.8 cm and natural durability of 19.67 days. Meanwhile, gerbera plants stop growing after 15 days in the Bio-Life solution and 30 days in the Knop solution

MEDICAL STUDENTS’ EVALUATION OF AN ENGLISH FOR SPECIFIC PURPOSES COURSEBOOK: A CASE IN VIETNAM

The current study investigates students’ evaluation of the English for Specific Purposes (ESP) coursebook taught at a medical college in the Mekong Delta, Vietnam. After using it for a year, the users, including medical students and their teachers, have given some unofficial feedback on the book. This study provided insightful official information about how its student users perceive the coursebook they were adopting. Data on the evaluations of the ESP coursebook were gained from questionnaires administered to 166 students majoring in nursing and pharmacy in charge of ESP programs. Semi-structured interviews were employed with four students to get more specific apprehension. The results of this study indicated that students were satisfied with the ESP coursebook in terms of the covering of four skills, the presence of vocabulary and grammar, relevant content, understandable social and cultural context, suitability for mix-level students. In addition, participants perceived that communicative skills were not sufficiently presented, examples in grammar were not more interesting, the illustrations were not diverse and enough, and the cover was simple but not appealing. Suggestions regarding the pedagogical implications for the adoption and evaluation of the coursebook were discussed

Theoretical Framework on the Role of Knowledge Management for Students on Academic Performance

Knowledge management is a developing sector that has received lots of consideration and support from the community which is industrial. Knowledge management is a young academic field which has not been built up a systematized and unified framework. This paper reviews the role of knowledge management for students on academic performance by using the structural equation modeling. Through applying knowledge management in the study process can help students to gain better results. As a result, it can be expected to shed light on the relative importance of knowledge management on students’ academic performance. Keywords: Knowledge management, Academic performance, digital economy DOI: 10.7176/IKM/11-2-05 Publication date:March 31st 202

Tertiary students’ preferences on extracurricular activities for English learning: Voices from the field of Advanced Program in Biotechnology

In Vietnam, where English plays a vital role in the country’s development, extracurricular activities for English learning are considered an effective reform for enhancing citizens’ English proficiency. Previous studies have showed the positive impact of extracurricular activities on language learners’ outcomes. Yet, almost none of them has investigated students’ voices about what, how, when, and where they want these activities to be organized. This current study was employed to fill that gap in the field of biotechnology (advanced program). A 77-item questionnaire was sent to 148 students who learned biotechnology in an advanced program at a tertiary institution in the Mekong Delta of Vietnam. The results indicated the students preferred mental activities (M=4.00) to others. Moreover, they would like to travel to experience cultures from English-speaking countries (M=4.11). Further extracurricular activities were encouraged to be organized on their university campus (M=3.63). The students also preferred short-term activities at weekends to those that were organized over a long period. The study proposed a model for further extracurricular activities at the end of this writing

Preparation and characterization of magnesium hydroxyapatite coatings on 316L stainless steel

Magnesium hydroxyapatite coatings (MgHAp) were deposited on the surface of 316L stainless steel (316L SS) substrates by electrodeposition technique. Different concentrations of Mg2+ ion were incorporated into the apatite structure by adding Mg(NO3)2 into electrolyte solution containing 3×10-2 M Ca(NO3)2, 1.8×10-2 M NH4H2PO4 and   6×10-2 M NaNO3. With Mg2+ concentration 1×10-3 M, the obtained coatings have 0.2 wt% Mg2+. The influences of scanning potential ranges, scanning times to deposit MgHAp coatings were researched. The analytical results FTIR, SEM, X-ray, EDX, thickness and adhension strength showed that MgHAp coatings were single phase of HAp, fibrous shapes, thickness 8.1 µm and adhesion strength 7.20 MPa at the scanning potential ranges of 0÷-1.7 V/SCE and scanning times of 5 scans. Keywords. 316L SS, Electrodeposition, MgHAp

STUDENTS' PERCEPTION OF THE INFLUENCE OF INTONATION IN ENGLISH ON CONVEYING THE MEANING OF SPEECH IN COMMUNICATION

In communication, intonation plays an important role in conveying the meaning of a speech. In this article, we study students' perception of the influence of intonation in conveying the meaning of speech in communication to propose solutions to help students overcome intonation errors when communicating, as well as, help teachers have appropriate intonation teaching methods. Our data and analysis are based on research documents, surveys, and in-depth interviews with students. According to the study results, most students are well aware of the importance of intonation and of the factors affecting intonation, and they are also aware of the causes of intonation errors. However, students do not apply their knowledge of intonation to speech, they stop at the cognitive level. The study indicates that students often make intonation mistakes in Tag-question, Wh-question, and Imperative sentence in communication.  Article visualizations

Vacuum Stability in Supersymmetric Reduced Minimal 3-3-1 Model

We investigate the vacuum stability conditions of theSupersymmetric reduced minimal 331 model (SUSYRM331) that createimportant  consequences on  Higgs mass spectrum as well assoft-parameters of the model. We prove that if this condition issatisfied then all Higgses are massive. Furthermore,soft-parameters should be in order of $SU(3)_L$ scale. Based onthis, we investigate in detail masses of CP-even neutral  anddoubly charged Higgses in the model. The  neutral Higgs sectorincludes one light Higgs with mass at tree level $m_{H^0_1}\simeq m_Z|\cos 2\gamma | 92.0$ GeV and three other heavy Higgses. Fordoubly charged Higgses, there may exist a light Higgs which can beobserved by recent colliders such as LHC

Optimization of Weld Parameters in Wire and Arc-Based Directed Energy Deposition of High Strength Low Alloy Steels

This paper aims to investigate the fabrication of high strength low alloy (HSLA) steels by wire and arc-based directed energy deposition (WADED). Firstly, the relationship between the process variables (including the travel speed-V, the current-C, and the voltage-U) and the geometrical characteristics of weld beads (including the bead height (BH), bead width (BW), and melting pool length (MPL)) was investigated. Secondly, the optimal process variables were identified using the desirability approach. The results indicate that voltage-U has the highest impact on BW and MPL, meanwhile the travel speed-V is the most impacting factor on BH. The optimal variables for the WADED process of HSAL steels are V = 0.3 m/min, C = 160 A, and U = 19 V. The component fabricated with the optimal variables is fully dense without spatters and defects, confirming the efficiency of the WADED process for HSLA steels

Characterization of arsenic-resistant endophytic Priestia megaterium R2.5.2 isolated from ferns in an arsenic-contaminated multi-metal mine in Vietnam

Bioremediation is a biological process to remove or neutralize environmental pollutants. This study was carried out to investing at the efficacy of arsenic resistant endophytic bacteria isolated from Pteris vittata, Pityrogramma calomelanos, Blenchum orientale, and Nephrolepis exaltata, which grow in a highly arsenic (As) contamination mining site in Vietnam. Their segmented roots, stems, and leaves were homogenized separately and inoculated on LB agar plates containing 5mM As(III) and As(V). A total of 31 arsenic resistant endophytic strains were selected, in which strain R2.5.2 isolated from the root of P. calomelanos had the highest arsenic resistant capability. Strain R2.5.2 tolerated up to 320 mM and 160 mM of arsenate and arsenite, respectively. The strain developed well on a media of 0.1 5% NaCl, at 20-40ºC and pH 5 9, and actively utilized most of the sugar sources. It had a high IAA biosynthesis capacity with an average concentration of 19.14 mg/L, tolerated to 0.5-16 mM concentration of Ag+, Hg2+, Co2+, Ni2+, Cu2+, Cr4+, and reduced As(V). Based on 16s rDNA, R2.5.2 was identified as Priestia megaterium. The ars C gene coding for arsenate reductase catalyzing reduction of As(V) was successfully amplified in P. megaterium R2.5.2.  The selected strain may have potential use for bioremediation practice

The Impact of Social Media Marketing on Brand Awareness and Purchase Intention: Case Study of Vietnam's domestic fashion brands

The study aimed to examine the impact of social media marketing on brand awareness and purchase intention for Vietnamese domestic fashion brands. Quantitative research was conducted on 302 Vietnamese people of Generation Z. The questionnaire designed on Google forms was sent to research samples who were willing to participate. Research results determined the role and benefits of social media marketing in 2 aspects: (1) information about the brand of social media marketing on social networks and (2) brand engagement on social networks. Social media marketing has a positive impact on brand awareness and purchase intention of Vietnamese domestic fashion brands. In particular, brand information when communicating on social networks has a direct and positive impact on brand awareness and purchase intention. Brand engagement on social networks has a positive direct impact on brand awareness and a positive indirect impact on purchase intention through brand awareness. The research results show that Vietnamese domestic fashion brands do quite well in social media marketing, and are highly appreciated by the online community of generation Z in Vietnam. In the future, in order to improve brand awareness and purchase intention, Vietnamese domestic fashion brands need to pay attention to the brand information properties of social media marketing programs and need to invest more in brand engagement characteristics of social networks. Keywords: social media marketing, brand awareness, purchase intentio