Colostrum quality, intestinal microbiota and implications for health in young dairy calves

The early life of calves in southern Vietnam and in Sweden were studied in this thesis, with the focus on colostrum quality, gut microbial communities and antimicrobialresistant Escherichia coli. The first of four studies showed that most cows on smallholder farms in Vietnam produced colostrum of good quality and that only around 10% of calves suffered from failure of passive immune transfer. In a second study, bacterial communities in colostrum and in calf faeces samples collected at birth and at 14 days of age were identified by terminal restriction fragment length polymorphism (T-RFLP). The results showed that the microbial communities in colostrum and faeces differed in composition, with greater similarities in composition between colostrum and faeces from newborn calves than faeces from 14-day-old calves. Microbial composition also differed significantly between faeces from newborn and 14-day-old calves. Sequencing of 16S rRNA gene amplicons from a subset of faeces samples from healthy calves and calves treated for diarrhoea with antimicrobial drugs revealed significant differences between the groups, with higher relative abundances of Faecalibacterium and Butyricicoccus in healthy calves. In a third study, bacterial composition in intestinal contents and in mucosal scrapings collected from various gut segments in two- and seven-day-old calves was characterized by sequencing 16S rRNA gene amplicons using Illumina MiSeq. It was found that microbial community composition was associated with intestinal segment, with major differences in composition between proximal and distal parts of the gastrointestinal tract. However, microbial composition showed high similarity for segments in close proximity within the gut. Lactobacillus was present in quite high levels in the abomasum and duodenum, whereas Escherichia were more associated with the ileum, caecum, colon and faeces. Microbial composition and diversity altered with age and, although the microbiota in mucosa and gut content remained similar in general, certain microbial groups dominated in either mucosa or gut content. The fourth study revealed high levels of multidrug-resistance in Escherichia coli isolated from Vietnamese calves (53% of isolates tested), with blacCTM-M-1 (2 isolates), blacCTM-M-9 (1 isolate) and blacCMY-2 (1 isolate) being the main β-lactamase resistance groups detected. There was a high incidence of plasmid-mediated quinolone resistance (PMQR) genes in the E. coli isolates (21%). Overall, these results suggest that colostrum feeding and health are key factors affecting gut microbial community in the early life of dairy calves, but that antimicrobial resistance is an emerging problem on smallholder dairy farms in Vietnam

Assessing Student’s Acceptance of Digital Transformation in Business and Management Universities in Vietnam

In recent years, the trend of digital transformation in education has increased significantly. A series of policies to promote the digital transformation of education have been issued, gradually completing the legal corridor such as the regulations on applying information technology, information in management, organization of online training, the use of the entire industry database system. Therefore, this article is the result of a more comprehensive research project and aims to analyze the digital transformation acceptance of college students in Economic - Business Universities in the North of Vietnam. The Unified Theory of Acceptance and Use of Technology (UTAUT) and independent variable Perceived Security (PS) have been combined together in order to support the survey. The data was analyzed using the method of multiple regression. These findings shed the light on the digital transformation acceptance level of students with the positive link of Performance Expectancy (PE), Social Influence (SI), Perceived Security (PS) and Facilitating Conditions (FC) on Behavioral Intention of digital transformation and its Use Behavior. Moreover, the study also has the contribution to provide orientations and solutions that will be proposed to approach the trend encouraging the application of digital transformation into higher education specifically in the business field. Keywords: UTAUT, digital transformation, perceived security, higher education DOI: 10.7176/JESD/12-8-02 Publication date: April 30th 202

Assessment of blasted excavation inaccuracy at tunnel face and influences on tunnelling effectiveness

Blasting has been the most effective solution for tunnel excavation in hard rock. The accuracy of the blasting works is demonstrated by the similarity between the design and the actual excavation boundary. Hence, the overbreak and underbreak of the tunnel boundary are used to evaluate the tunnel excavation. Widely applied for rock tunnelling, New Austrian Tunnelling Method (NATM) has been used for almost all highway tunnels in Vietnam. The assessment of the previous projects is essential since it provides learnt experiences and enriches the knowledge to handle the tunnelling technology. With this aim, the paper studied the case of a 500m NATM tunnel located on the N01 national highway in Central Vietnam. The practical excavation zone was examined, and the overbreak and underbreak of the tunnel boundary during the excavation by explosive was investigated. The dependences of the overbreak and underbreak on the geological and technical conditions were indicated. The tunnelling effectiveness was then assessed through the additional materials and works for the face correction activities

Assessment of blasted excavation inaccuracy at tunnel face and influences on tunnelling effectiveness

Blasting has been the most effective solution for tunnel excavation in hard rock. The accuracy of the blasting works is demonstrated by the similarity between the design and the actual excavation boundary. Hence, the overbreak and underbreak of the tunnel boundary are used to evaluate the tunnel excavation. Widely applied for rock tunnelling, New Austrian Tunnelling Method (NATM) has been used for almost all highway tunnels in Vietnam. The assessment of the previous projects is essential since it provides learnt experiences and enriches the knowledge to handle the tunnelling technology. With this aim, the paper studied the case of a 500m NATM tunnel located on the N01 national highway in Central Vietnam. The practical excavation zone was examined, and the overbreak and underbreak of the tunnel boundary during the excavation by explosive was investigated. The dependences of the overbreak and underbreak on the geological and technical conditions were indicated. The tunnelling effectiveness was then assessed through the additional materials and works for the face correction activities

Investigation of the estrogenic activity of Pueraria candollei variety mirifica extract on rats

Background: Pueraria candollei variety mirifica (PM) has been widely used as ingredient in many rejuvenating products. In this study, we aimed to assess the estrogenic activity of PM extract grown in Vietnam.Methods: Estrogenic activity of PM extract was estimated on immature female rats by using uterotrophic method to measure the weight of the reproductive organs. Estrogenic activity of PM extract also was investigated in mature female ovariectomized rats by evaluating the vaginal cells growth, reproductive organs weight, serum estradiol concentration.Results: Our results showed that PM extract at doses of 100 mg/kg, 200 mg/kg had increased the reproductive organs weight in immature rats and female ovariectomized rats. In addition, PM extract had increased the serum estradiol concentration and the vaginal cells growth by increasing the percentage of keratinocytes in female ovariectomized rats.Conclusions: Our results showed that PM extract has strong estrogenic activity in rats

Attenuation coefficient for surface acoustic waves in fluid region

In recent years, surface acoustic wave devices used in bio-sensing applications have demonstrated high sensitivity in the detection of fluid properties such as density, viscosity, stream velocity. In this paper, a more effective measurement of the SAWsensorstructure is presented. It is reported that at density of 6 g/cm3, the amplitude of mechanical wave is excited while for electrical signal, attenuation at 3 g/cm3 reaches a peak.In our analysis, single–crystal Aluminium Nitride substrate is used. Several parameters of leaky waves including displacement, decay constant in the liquid media are analyzed

High level of multidrug-resistant Escherichia coli in young dairy calves in southern Vietnam

This study investigated the occurrence of antimicrobial-resistant Escherichia coli in dairy calves in southern Vietnam. Fecal samples were taken directly from the rectum of 84 calves from 41 smallholder dairy farms, when newborn and at 14 days of age for isolation of E. coli. Escherichia colistrains were isolated from 144 of the 168 fecal samples tested. Of the 144 E. coli isolates, 40% were found to be susceptible to all 12 antimicrobial drugs tested and 53% of the E. coli isolates were resistant to at least three antimicrobials. Calves were colonized with antimicrobial-resistant E. coli already on the day of birth. Resistance to tetracycline was most common, followed by resistance to sulfamethoxazole, ampicillin, trimethoprim, and ciprofloxacin. Four isolates carried a gene encoding for extendedspectrum cephalosporinases (ESC), and these genes belonged to blaCTX-M group 1 (2 isolates), blaCTX-M group 9 (1 isolate), and blaCMY-2 (1 isolate). Thirty-three isolates had a plasmid-mediated quinolone resistance (PMQR) phenotype, and 30 of these carried the qnrS gene. These results are of importance for management routines of dairy cattle to prevent the spread of antimicrobial resistance

Factors affecting the creativity of high school students

Creativity is a vital personality quality of each individual. Each person has their potential for creativity, and it can be nurtured and developed in an appropriate and safe environment. The purpose of the study was to find out which factors from schools and students themselves affect creativity as well as the association between creativity and age, gender and giftedness of students, which then a basis to adjust and establish appropriate methods from schools, families, and students themselves to develop elements and their creativity. The study was conducted on 108 high school students in three grades from giftedness and non-giftedness schools. The data was collected through a survey method using a self-constructed questionnaire and drawing creativity test TCT-DP to determine students' creativity levels and personal information. The study's finding, which uses mathematical methods and one-way analysis of variance, reveals that factors affecting elements and creativity level are objective factors including education environment from school; behavior of teachers, and subjective factors including interests, perspectives, and thoughts of students. It was also found that there were no significant differences in the components of creativity and creativity among students in different grades, gender, and groups of giftedness schools

Autologous bone marrow mononuclear cell infusion for liver cirrhosis after the Kasai operation in children with biliary atresia

Aim: To evaluate the safety and early outcomes of autologous bone marrow mononuclear cell (BMMNC) infusion for liver cirrhosis due to biliary atresia (BA) after Kasai operation. Methods: An open-label clinical trial was performed from January 2017 to December 2019. Nineteen children with liver cirrhosis due to BA after Kasai operation were included. Bone marrow was harvested through anterior iliac crest puncture under general anesthesia. Mononuclear cells (MNCs) were isolated by Ficoll gradient centrifugation and then infused into the hepatic artery. The same procedure was repeated 6 months later. Serum bilirubin, albumin, alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl transferase, and prothrombin time were monitored at baseline, 3 months, 6 months, and 12 months after the first transplantation. Esophagoscopies and liver biopsies were performed in patients whose parents provided consent. Mixed-effect analysis was used to evaluate the changes in Pediatric End-Stage Liver Disease (PELD) scores. Results: The average MNC and CD34+ cell counts per kg body weight were 50.1 ± 58.5 × 106/kg and 3.5 ± 2.8 × 106 for the first transplantation and 57.1 ± 42.0 × 106/kg and 3.7 ± 2.7 × 106 for the second transplantation. No severe adverse events associated with the cell therapy were observed in the patients. One patient died 5 months after the first infusion at a provincial hospital due to the rupture of esophageal varices, while 18 patients survived. Liver function was maintained or improved after infusion, as assessed by biochemical tests. The severity of the disease reduced markedly, with a significant reduction in PELD scores. Conclusion: Autologous BMMNC administration for liver cirrhosis due to BA is safe and may maintain or improve liver function. Trial registration: ClinicalTrials.gov identifier: NCT03468699. Name of the registry: Vinmec Research Institute of Stem Cell and Gene Technology. https://clinicaltrials.gov/ct2/show/NCT03468699?cond=biliary+atresia&cntry=VN&draw=2&rank=2. Registered on March 16, 2018. The trial results will also be published according to the CONSORT statement at conferences and reported in peer-reviewed journals