A Consideration of Cooperative Learning to Enhance Pre-service Teachers’ Achievement in Tertiary English as a Foreign Language (EFL) Classrooms in Thailand

Cooperative learning has become a popular instructional practice around the world. It requires students working together in small groups to help support each other in maximising their own learning as well as that of others to accomplish a shared goal. A cooperative learning method, especially, Student Teams Achievement Divisions (STAD) developed by Slavin (1982) was implemented in the study. The study investigated the effectiveness of cooperative learning to enhance the English achievement of EFL (English as a foreign language) students in tertiary teacher education in Thailand. It also examined participants’ attitudes towards cooperative learning. The study began with a structured review of existing empirical studies to establish whether STAD could be a promising method to use in developing English proficiency in EFL and ESL (English as a second language) contexts. The review also helped identify the challenges and barriers to implementing the method and informed the primary research in terms of achievement tests, instructor training, time allowance for team study and material preparation. The review and synthesis of 28 studies revealed several beneficial suggestions regarding cooperative learning implementation in normal educational settings. However, the credibility of the overall evidence was weak, with most studies involving key methodological flaws. To examine the effectiveness of the method, a cluster randomised controlled trial (RCT) at the university level was used. The participants were 13 instructors and 614 students from 13 universities (forming 13 clusters). A total of eight universities that agreed to participate in the intervention were randomly assigned to experimental and control groups with four universities in each group. Another five universities agreed to complete the pre-test and post-test and are described in this thesis as an additional comparison group. The participating instructors were 13 Thai university instructors of English language from 13 Rajabhat Universities in Thailand. Their students were first-year pre-service teachers who were majoring in English in the Faculty of Education. The trial was carried out in one term consisting of 16 class sessions. The research instruments consisted of two parallel standardised English achievement tests, two attitude questionnaires (teacher and student) and classroom observations with ad hoc interviews. The results showed that the use of cooperative learning in tertiary EFL classrooms in Thailand is feasible. In terms of attitudes, both instructors and students were generally positive towards cooperative learning and supported its activities. Students in the treatment group did slightly better (ES = +0.09) when compared to all comparator groups. However, when considering the randomised experimental and control groups, the control group improved their post-test score (+0.26) while the experimental group declined (-0.20). Overall, cooperative learning showed no clear benefit for students’ English language achievement. The process evaluation revealed the key factors that facilitated the implementation were teacher training and support, preparation and availability of teaching resources and materials, teachers’ positive attitudes and the duration of cooperative learning instruction. Some barriers were also found, including students’ negative attitudes, inappropriate classroom settings and facilities, and instructors’ workload. Unfortunately, since the study was carried out during the COVID-19 pandemic, none of the universities were able to complete the course of 16 classes as planned. The number of classes students could meet in their normal classroom conditions was approximately 8 to 12. Different modes of lesson delivery (face-to-face, online and hybrid) were also reported. A replication of the study is needed for a more accurate assessment of the STAD method. Both the structured review and the cluster RCT suggest no strong evidence that the cooperative learning method, namely STAD, led to improved pre-service teachers’ English language achievement in Thailand. However, this does not necessarily mean the method does not work. The lack of impact might be due to the challenges faced in the delivery of the intervention during the pandemic. This was compounded by the lack of complete randomisation used in the study. It is, therefore, difficult to draw more definite conclusions about the effectiveness of STAD. It might be wise to conduct further robust evaluations involving a large number of educational institutions before any considerable investment can be made to introduce this method in higher education institutions in Thailand. In the meantime, there may be other approaches with a more promising evidence base which may enhance students’ English language achievement

Isolation and Identification of a Cellulase-producing Bacillus sp. Strain BR0302 from Thai Coastal Wetland Soil

This study proposed the isolation, screening and identification of cellulase-producing bacteria from Thai coastal wetland soil. Eighty seven bacterial strains which demonstrated cellulase-producing bacteria were investigated for cellulolytic properties. The bacterium identified as Bacillus cereus strain BR0302 exhibited the highest hydrolysis activity on carboxymethylcellulose agar plates. Cellulolytic performance for CMCase activity and FPase activity was 0.121 ± 0.006 and 0.057 ± 0.001 U/mL respectively. Cellulolytic characteristics showed that the B. cereus strain BR0302 could be used for the hydrolysis of cellulosic biomass for biofuel production

Bio-Based Polyols from Seed Oils for Water-Blown Rigid Polyurethane Foam Preparation

The preparation of water-blown rigid polyurethane (RPUR) foams using bio-based polyols from sesame seed oil and pumpkin seed oil has been reported. Polyols synthesis involved two steps, namely, hydroxylation and alcoholysis reaction. FTIR, NMR, and ESI-MS were used to monitor the process of the synthesized polyols and their physicochemical properties were determined. The resulting polyols have OH number in the range of 340–351 mg KOH/g. RPUR foams blown with water were produced from the reaction of biopolyols with commercial polymeric methylene diphenyl diisocyanate (PMDI). The proper PUR formulations can be manipulated to produce the desired material applications. These seed oil-based RPUR foams exhibited relatively high compressive strength (237.7–240.2 kPa) with the density in the range of 40–45 kg/m3. Additionally, the cell foam morphology investigated by scanning electron microscope indicated that their cellular structure presented mostly polygonal closed cells. The experimental results demonstrate that these bio-based polyols can be used as an alternative starting material for RPUR production

Preparation and characterization of bis-[1,3,5]triazinyl diazenes and their utilization as flame retardants in polypropylene films

A series of bis-[1,3,5]triazinyl diazenes and two metal complexes thereof were synthesized and tested as new flame retardants in polypropylene films. It was observed that electron withdrawing triazinyl ring substituents (i.e. Cl and phenyl moieties) improved the thermal stability of diazene compounds, whereas electron donating groups (i.e. methoxy, dimethylamino and ethylthio moieties) had a destabilizing effect. TGA, DTA/DSC, NMR and ATR-FTIR were used for the characterization. Quantum mechanical modeling (Gaussian 09) was also utilized to facilitate the interpretation of the NMR data. Bis-(4,6-dichloro-[1,3,5]triazin-2-yl)-diazene 1 and bis-(4,6-dimethoxy-[1,3,5]triazin-2-yl)-diazene 2 were found to be effective flame retardants in polypropylene films and DIN4102-1 B2 classification was reached already at a loading of 0.5 wt%. Interestingly, the copper complex of 2 showed even higher fire retardant activity than its precursor 2, whereas the corresponding zinc complex exhibited lower flame retardant efficacy than its precursor

Diversity and Activity of Aquatic Cellulolytic Bacteria Isolated from Sedimentary Water in the Littoral Zone of Tonle Sap Lake, Cambodia

Tonle Sap Lake is the largest freshwater lake in Southeast Asia, and it is regarded as one of the most biodiverse freshwater ecosystems in the world. Studies concerning aquatic cellulolytic bacteria from Tonle Sap Lake remain scarce. Cellulolytic bacteria and their cellulases play a vital role in the biogeochemical cycles of lake environments, and their application in biotechnological industries is likewise an important component of their usage. This study aimed to assess the isolation, genetic identification, bioinformatic analyses, and activity characterization of aquatic cellulolytic bacteria. The cellulolytic bacteria isolated from sedimentary water samples in the littoral zone of the lake belong to the genera Aeromonas, Bacillus, and Exiguobacterium. Several isolated aquatic bacteria were designated as rare cellulolytic microbes. Remarkably, B. mojavensis strain REP303 was initially evidenced by the aquatic cellulolytic bacterium in freshwater lake ecosystems. It was considered a highly active cellulolytic bacterium capable of creating a complete cellulase system involving endoglucanase, exoglucanase, and β-glucosidase. The encoded endoglucanase belongs to the glycosyl hydrolase family 5 (GH5), with a carboxymethylcellulase (CMCase) activity of 3.97 ± 0.05 U/mL. The optimum temperature and pH for CMCase activity were determined to be 50 °C at a pH of 7.0, with a stability range of 25–55 °C at a neutral pH of 7.0–8.0. The CMCase activity was enhanced significantly by Mn2+ and was inhibited considerably by EDTA and ethyl-acetate. In conclusion, this study is the first to report data concerning aquatic cellulolytic bacteria isolated from the littoral zone of Tonle Sap Lake. A novel strain of isolated cellulolytic B. mojavensis could be applied in various cellulose-based industries

Klebsiella and Enterobacter Isolated from Mangrove Wetland Soils in Thailand and Their Application in Biological Decolorization of Textile Reactive Dyes

Wastewater released from textile and dye-based industries is one of the major concerns for human and aquatic beings. Biological decolorization using ligninolytic bacteria has been considered as an effective and alternative approach for the treatment of dyeing wastewater. This study aimed to assess the isolation, characterization and application of soil bacteria isolated from mangrove wetlands in Thailand. Four active bacteria were genetically identified and designated as Klebsiella pneumoniae strain RY10302, Enterobacter sp. strain RY10402, Enterobacter sp. strain RY11902 and Enterobacter sp. strain RY11903. They were observed for ligninolytic activity and decolorization of nine reactive dyes under experimental conditions. All bacteria exhibited strong decolorization efficiency within 72 h of incubation at 0.01% (w/v) of reactive dyes. The decolorization percentage varied from 20% (C.I. Reactive Red 195 decolorized by K. pneumoniae strain RY10302) to 92% (C.I. Reactive Blue 194 decolorized by Enterobacter sp. strain RY11902) in the case of bacterial monoculture, whereas the decolorization percentage for a mixed culture of four bacteria varied from 58% (C.I. Reactive Blue 19) to 94% (C.I. Reactive Black 1). These findings confer the possibility of using these bacteria for the biological decolorization of dyeing wastewater