Upper Primary Students' Perceptions of Small Group Learning in Learning Vietnamese Language

The purpose of this study was to investigate the perceptions of upper-year students in Vietnamese primary schools about learning in small groups when studying Vietnamese language in comparison to traditional methods. Students’ perceptions of small group learning were explored through examination of five main factors: benefits, difficulties, group types, individual accountability, and group assessment. An interpretive approach was used to explore the topic, from which data were collected in a two-phase multi-case study using both quantitative and qualitative methods. Four classes of three primary schools in Ho Chi Minh City, having different applications of small groups in learning, were selected for observation and survey by questionnaire. Twenty four students from the first phase of the study varying in gender and learning achievement were chosen for face-to-face interviews to examine more in-depth their perceptions about small group learning. To improve the trustworthiness of the research, teachers from these classes and principles of the schools were interviewed to obtain a more accurate overview of the research. The study found that overall, Vietnamese upper-primary students preferred to learning in small groups to the traditional whole-class model despite the differences in implementing small group learning in each school. The results showed a positive concurrence with existing literature on the main findings, such as the three main benefits to students’ outcomes (e.g. academic achievement, social skills, and attitudes); and some inevitable difficulties when using this method for learning (e.g. time management, isolation and lack of group skills). The students’ choices of group types also reflected the current international students’ perceptions (e.g. preference for heterogeneous ability but homogeneous gender group). The research also presented some interesting points unique to the Vietnamese context which might enrich the current literature of students’ perceptions of small group learning. They were the preference for large group sizes, the two-aspects of leadership, the preference for whole-group assessment, and the suitability of this method for learning Vietnamese language rather than other subjects. The research also showed the underlying influences of the desire for better achievement, the consideration for others’ feelings and the collective cultural context on Vietnamese upper primary students’ views of small group learning in learning Vietnamese language. The relationships between students’ gender and achievement to their perceptions of small group learning were also mentioned and described though these were not strong enough to generalise. A theoretical framework was proposed to illustrate the research findings. These findings suggest that small group learning should be implemented more frequently in Vietnamese primary schools and the study recommends that there be further training in group skills for students

Radicular cyst in a primary molar following pulp therapy with gutta percha : a case report and literature review

A radicular cyst (RC) in deciduous dentition is relatively rare. This clinical report presents a case of RC that condition derived from a primary molar undergone an endodontic treatment with gutta-percha approximately one year ago. In addition, we also considered whether intracanal medicaments and gutta-percha filling material related to the formation and development of the cyst or not

Study on the effect of carbon black, carbon nanotube on the properties of rubber blend acrylonitrile butadiene rubber (NBR)/polyvinyl chloride (PVC)

The effects of carbon nanotube (CNT) in combination with carbon black (CB) on the properties of acrylonitrile butadiene rubber (NBR)/polyvinyl chloride (PVC) (70/30) were investigated. The results reveal that the maximal tensile strength of the rubber blend was obtained by the fillers ratio of CB:CNT = 39:1. At this filler ratio, the thermal stability and heat conductivity of the rubber blend were also significantly improved. The analysis of FE-SEM images and DMA diagram indicate that the dispersion of filler as well as the interaction between fillers and rubber matrix was improved by the incorporation of CNT. Keywords. NBR/PVC blends, carbon nanotube (CNT), carbon black (CB), nanocomposites

TextANIMAR: Text-based 3D Animal Fine-Grained Retrieval

3D object retrieval is an important yet challenging task, which has drawn more and more attention in recent years. While existing approaches have made strides in addressing this issue, they are often limited to restricted settings such as image and sketch queries, which are often unfriendly interactions for common users. In order to overcome these limitations, this paper presents a novel SHREC challenge track focusing on text-based fine-grained retrieval of 3D animal models. Unlike previous SHREC challenge tracks, the proposed task is considerably more challenging, requiring participants to develop innovative approaches to tackle the problem of text-based retrieval. Despite the increased difficulty, we believe that this task has the potential to drive useful applications in practice and facilitate more intuitive interactions with 3D objects. Five groups participated in our competition, submitting a total of 114 runs. While the results obtained in our competition are satisfactory, we note that the challenges presented by this task are far from being fully solved. As such, we provide insights into potential areas for future research and improvements. We believe that we can help push the boundaries of 3D object retrieval and facilitate more user-friendly interactions via vision-language technologies.Comment: arXiv admin note: text overlap with arXiv:2304.0573

An open label randomized controlled trial of tamoxifen combined with amphotericin B and fluconazole for cryptococcal meningitis

Background: Cryptococcal meningitis has high mortality. Flucytosine is a key treatment but is expensive and rarely available. The anti-cancer agent tamoxifen has synergistic anti-cryptococcal activity with amphotericin in vitro. It is off-patent, cheap, and widely available. We performed a trial to determine its therapeutic potential. Methods:Open label randomized controlled trial. Participants received standard care - amphotericin combined with fluconazole for the first two weeks - or standard care plus tamoxifen 300mg/day. The primary end point was Early Fungicidal Activity (EFA) - the rate of yeast clearance from cerebrospinal fluid (CSF). Trial registration https://clinicaltrials.gov/ct2/show/NCT03112031 . Results: 50 patients were enrolled, (median age 34 years, 35 male). Tamoxifen had no effect on EFA (- 0.48log10 colony-forming units/mL/CSF control arm versus -0.49 tamoxifen arm, difference - 0.005log10CFU/ml/day, 95%CI: -0.16, 0.15, P=0.95). Tamoxifen caused QTc prolongation. Conclusion: High dose tamoxifen does not increase the clearance rate of Cryptococcus from CSF. Novel, affordable therapies are needed. Funding:The trial was funded through the Wellcome Trust Asia Programme Vietnam Core Grant 106680 and a Wellcome Trust Intermediate Fellowship to JND grant number WT097147MA

Safety and efficacy of fluoxetine on functional outcome after acute stroke (AFFINITY): a randomised, double-blind, placebo-controlled trial

Background Trials of fluoxetine for recovery after stroke report conflicting results. The Assessment oF FluoxetINe In sTroke recoverY (AFFINITY) trial aimed to show if daily oral fluoxetine for 6 months after stroke improves functional outcome in an ethnically diverse population. Methods AFFINITY was a randomised, parallel-group, double-blind, placebo-controlled trial done in 43 hospital stroke units in Australia (n=29), New Zealand (four), and Vietnam (ten). Eligible patients were adults (aged ≥18 years) with a clinical diagnosis of acute stroke in the previous 2–15 days, brain imaging consistent with ischaemic or haemorrhagic stroke, and a persisting neurological deficit that produced a modified Rankin Scale (mRS) score of 1 or more. Patients were randomly assigned 1:1 via a web-based system using a minimisation algorithm to once daily, oral fluoxetine 20 mg capsules or matching placebo for 6 months. Patients, carers, investigators, and outcome assessors were masked to the treatment allocation. The primary outcome was functional status, measured by the mRS, at 6 months. The primary analysis was an ordinal logistic regression of the mRS at 6 months, adjusted for minimisation variables. Primary and safety analyses were done according to the patient's treatment allocation. The trial is registered with the Australian New Zealand Clinical Trials Registry, ACTRN12611000774921. Findings Between Jan 11, 2013, and June 30, 2019, 1280 patients were recruited in Australia (n=532), New Zealand (n=42), and Vietnam (n=706), of whom 642 were randomly assigned to fluoxetine and 638 were randomly assigned to placebo. Mean duration of trial treatment was 167 days (SD 48·1). At 6 months, mRS data were available in 624 (97%) patients in the fluoxetine group and 632 (99%) in the placebo group. The distribution of mRS categories was similar in the fluoxetine and placebo groups (adjusted common odds ratio 0·94, 95% CI 0·76–1·15; p=0·53). Compared with patients in the placebo group, patients in the fluoxetine group had more falls (20 [3%] vs seven [1%]; p=0·018), bone fractures (19 [3%] vs six [1%]; p=0·014), and epileptic seizures (ten [2%] vs two [<1%]; p=0·038) at 6 months. Interpretation Oral fluoxetine 20 mg daily for 6 months after acute stroke did not improve functional outcome and increased the risk of falls, bone fractures, and epileptic seizures. These results do not support the use of fluoxetine to improve functional outcome after stroke

Upper Primary Students' Perceptions of Small Group Learning in Learning Vietnamese Language

The purpose of this study was to investigate the perceptions of upper-year students in Vietnamese primary schools about learning in small groups when studying Vietnamese language in comparison to traditional methods. Students’ perceptions of small group learning were explored through examination of five main factors: benefits, difficulties, group types, individual accountability, and group assessment. An interpretive approach was used to explore the topic, from which data were collected in a two-phase multi-case study using both quantitative and qualitative methods. Four classes of three primary schools in Ho Chi Minh City, having different applications of small groups in learning, were selected for observation and survey by questionnaire. Twenty four students from the first phase of the study varying in gender and learning achievement were chosen for face-to-face interviews to examine more in-depth their perceptions about small group learning. To improve the trustworthiness of the research, teachers from these classes and principles of the schools were interviewed to obtain a more accurate overview of the research. The study found that overall, Vietnamese upper-primary students preferred to learning in small groups to the traditional whole-class model despite the differences in implementing small group learning in each school. The results showed a positive concurrence with existing literature on the main findings, such as the three main benefits to students’ outcomes (e.g. academic achievement, social skills, and attitudes); and some inevitable difficulties when using this method for learning (e.g. time management, isolation and lack of group skills). The students’ choices of group types also reflected the current international students’ perceptions (e.g. preference for heterogeneous ability but homogeneous gender group). The research also presented some interesting points unique to the Vietnamese context which might enrich the current literature of students’ perceptions of small group learning. They were the preference for large group sizes, the two-aspects of leadership, the preference for whole-group assessment, and the suitability of this method for learning Vietnamese language rather than other subjects. The research also showed the underlying influences of the desire for better achievement, the consideration for others’ feelings and the collective cultural context on Vietnamese upper primary students’ views of small group learning in learning Vietnamese language. The relationships between students’ gender and achievement to their perceptions of small group learning were also mentioned and described though these were not strong enough to generalise. A theoretical framework was proposed to illustrate the research findings. These findings suggest that small group learning should be implemented more frequently in Vietnamese primary schools and the study recommends that there be further training in group skills for students

Upper Primary Students' Perceptions of Small Group Learning in Learning Vietnamese Language

The purpose of this study was to investigate the perceptions of upper-year students in Vietnamese primary schools about learning in small groups when studying Vietnamese language in comparison to traditional methods. Students’ perceptions of small group learning were explored through examination of five main factors: benefits, difficulties, group types, individual accountability, and group assessment.  An interpretive approach was used to explore the topic, from which data were collected in a two-phase multi-case study using both quantitative and qualitative methods. Four classes of three primary schools in Ho Chi Minh City, having different applications of small groups in learning, were selected for observation and survey by questionnaire. Twenty four students from the first phase of the study varying in gender and learning achievement were chosen for face-to-face interviews to examine more in-depth their perceptions about small group learning. To improve the trustworthiness of the research, teachers from these classes and principles of the schools were interviewed to obtain a more accurate overview of the research.  The study found that overall, Vietnamese upper-primary students preferred to learning in small groups to the traditional whole-class model despite the differences in implementing small group learning in each school. The results showed a positive concurrence with existing literature on the main findings, such as the three main benefits to students’ outcomes (e.g. academic achievement, social skills, and attitudes); and some inevitable difficulties when using this method for learning (e.g. time management, isolation and lack of group skills). The students’ choices of group types also reflected the current international students’ perceptions (e.g. preference for heterogeneous ability but homogeneous gender group).  The research also presented some interesting points unique to the Vietnamese context which might enrich the current literature of students’ perceptions of small group learning. They were the preference for large group sizes, the two-aspects of leadership, the preference for whole-group assessment, and the suitability of this method for learning Vietnamese language rather than other subjects. The research also showed the underlying influences of the desire for better achievement, the consideration for others’ feelings and the collective cultural context on Vietnamese upper primary students’ views of small group learning in learning Vietnamese language. The relationships between students’ gender and achievement to their perceptions of small group learning were also mentioned and described though these were not strong enough to generalise. A theoretical framework was proposed to illustrate the research findings. These findings suggest that small group learning should be implemented more frequently in Vietnamese primary schools and the study recommends that there be further training in group skills for students.</p

LINEAR MULTI-REGRESION MODEL FOR ESTIMATING ACTUAL DAILY EVAPOTRANSPIRATION BASED ON S-SEBI METHOD OVER CAU RIVER BASIN OF VIETNAM USING LANDSAT-7 IMAGES

Calculating the actual evapotranspiration (ETa) is an important task in monitoring water balance in river basins, serving irrigation management in agriculture and in weather forecasting. In fact, it is difficult to measure ETa directly and most ETa applications are calculated using empirical-theoretical models. This paper proposes a linear multi-regression model to calculate ETa based on the relationship between ETa extracted by the Simple Surface Energy Balance Index (S-SEBI) with the surface biological-physical parameters, such as albedo, normal difference vegetation index (NDVI), surface temperature (Ts), and net surface solar radiation (Rnd) that were extracted from the Landsat-7 imagery dated November 23, 2001. The proposed model was evaluated based on ETa field observations on meteorological stations on November 4th, 2000 with Root Mean Square Error (RMSE) of 1.585 mm/day and Mean Absolute Error (RAE) of 35.44%. After eliminating the Mean Bias Error (MBE) the model achieves accuracy with RMSE = 0.702 mm/day and MAE = 17% (model accuracy is 83%)

The Effect of Multiwalled Carbon Nanotubes on the Thermal Conductivity and Cellular Size of Polyurethane Foam

Polyurethane (PU) foam is known as the popular material for the applications in many fields of industry and life. To improve the mechanical and thermal properties of this material, in this research, PU foam was reinforced with aniline-modified multiwalled carbon nanotubes (MWCNTs). Fourier transform infrared FTIR spectrum of modified MWCNTs showed the aniline was grafted on the surface of MWCNTs through the appearance of –NH2 stretches. The effect of MWCNTs with and without modification on the density, porosity, compressive strength, and heat conductivity of PU/MWCNT foam nanocomposites was investigated. The dispersibility of MWCNTs in the PU matrix was enhanced after modification with aniline. Compressive strength of PU nanocomposite reached the highest value after adding 3 wt.% of modified MWCNTs into PU foam. Besides, the water uptake of PU nanocomposites using 3 wt.% of MWCNTs was decreased to 13.4% as compared to that using unmodified MWCNTs. The improvement in thermal conductivity of PU/aniline-modified MWCNT nanocomposite was observed due to the change in the cellular size of PU foam in the presence of MWCNTs as shown by SEM images