THE PERCEIVED EFFECTS OF TEST-TAKING STRATEGIES INSTRUCTION ON EFL HIGH SCHOOL STUDENTS' MULTIPLE-CHOICE TESTS OF READING COMPREHENSION

This study aims to investigate whether the use of a text-taking strategy could enhance EFL high school learners' reading comprehension. It draws on the test-taking strategies suggested by Cohen and Upton (2007), to focus on the two main aspects, (1) the influence of applying test-taking strategies on EFL high school students’ reading comprehension tests and (2) their attitudes toward these strategies. In the pretest-posttest one-group design and descriptive quantitative research, the reading comprehension test and the questionnaire were used to collect the data of 90 EFL high school students in a school in rural Can Tho City. These students were assigned to apply test-taking strategies in a workshop every week in the second Semester of 2021-2022. The findings showed that (1) participating students’ reading comprehension scores improved after following the test-taking strategies after 07 weeks; and (2) students were positive about their being active in their testing practice despite certain challenges. As a result of such positive attitudes, they had high motivation for continuing their practice test-taking strategies for the future examination.  Article visualizations

Teachers’ feelings of safeness in school-family-community partnerships: Motivations for sustainable development in moral education

This study aims to get insights into teachers' safety feelings in families, schools, and communities’ partnerships to facilitate the Vietnam context’s moral education process. We used a survey method with the instrument having 19 Likert-scale items, namely teachers' feelings of safeness in SFC partnerships (SSFC). The data from 371 Vietnamese teachers followed a simple random sampling strategy. We conduct multiple regression analyses to get insight into the relationship between four groups of variables and teachers' feelings of safeness, namely teachers’ background, collaborated actions between teachers and families, families’ mental encouragement for teachers, and collaborated actions between families and communities. These results find that the school level, collaborated actions between teachers and families, and families’ mental encouragement for teachers are statistically significant to teachers’ feelings of safety. Moreover, the variable group of collaborated actions between teachers and families records the highest positive beta value in multiple regression analyses. In other words, the improvement of collaborated actions between teachers and families is a critical motivation to leverage teachers’ feelings of safeness in SFC partnerships. These results provide valuable information for sustainable development in moral education

Optimization of spray-drying conditions and quality assessment of dry extract from Perilla frutescens (L.) Britton leaves

Context: Perilla frutescens and its dried extract have been employed in food and pharmaceutical manufacturing due to the plant's biological activities, which include antibacterial, anti-allergic, anticancer, antiviral, antioxidant, and antidepressant properties. Despite numerous studies on preparing dry extracts from various medicinal herbs, no research has been conducted to optimize spray-drying conditions specifically for P. frutescens. Aims: To optimize the spray-drying parameters using BCPharSoft software and evaluate the quality of P. frutescens dry extract. Methods: D-optimal design based on four independent variables carrier type (Glucidex, Glucidex: Arabic gum 9:1, Glucidex: Arabic gum 8:2), carrier mass (10, 15, and 20 g), inlet air temperature (160, and 180℃) and flow rate (12, and 14 rpm/min) was applied to investigate the cause-effect relations and optimized preparation process. The drying performance, moisture content, total phenol, and total flavonoid content were investigated as four dependent variables. Results: All independent variables had significant effects on the dependent variables. The optimal parameters of the preparation process included using carrier Glucidex: Arabic gum at a ratio of 9:1, carrier mass of 19 g, inlet air temperature of 161°C, and flow rate of 12 rpm/min. The drying performance, moisture content, total phenol, and flavonoid content of the optimized P. frutescens dry extract were found to be 10.42%, 4.80%, and 90.57 mg GA/g, and 53.55 mg QE/g, respectively. Conclusions: Dried P. frutescens extract has been efficiently produced using the spray-drying technique, establishing a foundation for future manufacturing of pharmaceuticals and functional foods derived from P. frutescens

Evaluation of pesticide residues in vegetables from Mekong, Delta, Vietnam using LC-MS/MS

Purpose: To assess the levels of pesticide residues in commonly used vegetables in Vietnam as a reference for future monitoring. Methods: A total of 180 samples of six different fresh vegetables including watercress, mustard green, choy sum, daikon, okra, and yam were analyzed from Mekong Delta, Vietnam. Ten popular pesticides were evaluated using liquid chromatography-tandem mass spectrometry (LC-MS/MS) after extraction with a multi-residue method (QuEChERS method). Results: The results were assessed according to the maximum residue limit (MRL) provided by Codex for each pesticide in each commodity. Pesticide residues above the MRL were detected in 107 samples (59 %) and 63 samples (47 %) contained residues below the MRL. Multiple residues were present in 38.3% of the samples with two to five pesticides, and 0.6 % of samples were contaminated with more than five pesticide residues. Of the pesticides investigated, eight pesticides were detected, of which abamectin, alpha-cypermethrin, acetamiprid, chlorpyrifos- ethyl, chlorantraniliprole, fenobucarb, fipronil, and trichlorfon exceeded their MRLs. Pesticide residues were detected above MRLs in samples of watercress (14 samples), mustard green (24 samples), choy sum (25 samples), daikon (26 samples), and yam (18 samples). Chlorpyrifos-ethyl, and fipronil were detected in most of the vegetable samples (100% and 89.44%, respectively). Conclusion: The results indicate the occurrence of pesticide residues in commonly consumed vegetables in Vietnam. The need for the regular monitoring of pesticide residues and the sensitization of farmers to better pesticide safety practices, especially the need to adhere to recommended pre-harvest intervals is recommended

Enhancement diesel oil degradation by using biofilm forming bacteria on biochar

Biochar is defined as a carbon-rich, fine-grained, porous substance, which is produced by pyrolysis biomass with little or no oxygen. Biochar is usually produced from crop residues, wood biomass, animal litters, and solid wastes. Recently, biochar is increasingly receiving attention as an environmental-friendly approach, especially as a climate change mitigation strategy. Biochar is especilly demonstrated to remove diesel oil (DO) from soil and water. In this report, 4 biofilm forming bacteria including Klepsiella sp. VTD8, Pseudomonas sp. BQN21, Rhodococcus sp. BN5 and Stenotropomonas sp. QND8 were used to attach to biochar produced from husk to estimate the capacity of their DO removal. As the results, removal efficiency of biofilm formed by each strain VTD8, BQN21, BN5 and QND8 were 67, 73, 75 and 68 % with initial concentration of 39 g/l, respectively. On the other hand, mix species biofilm attached to husk carrier and without carrier degraded 98 and 78 %. Using husk without bacteria as absortion control, the amount of DO removal was 23 %. These results gave hint that using biochar produced from husk as carrier for biofilm forming bacteria to attach may increase efficiency of DO pollution treatment.Than sinh học (biochar) là một chất xốp có các gốc carbon và có nguồn gốc từ quá trình nhiệt phân sinh khối các loại chất thải, động, thực vật,… dưới điều kiện hạn chế oxy hoặc không có oxy. Hiện nay biochar đã được ứng dụng rộng rãi trong xử lý môi trường. Đặc biệt các biochar còn được chứng minh là có thể xử lý dầu diesel (diesel oil - DO) có trong đất và nước. Trong nghiên cứu này, chúng tôi sử dụng 4 chủng vi khuẩn tạo màng sinh học tốt là Klepsiella sp. VTD8, Pseudomonas sp. BQN21, Rhodococcus sp. BN5 và Stenotropomonas sp. QND8 để gắn lên chất mang là biochar làm từ trấu nhằm đánh giá hiệu quả xử lý DO của chúng. Kết quả cho thấy, sau 7 ngày, các chủng VTD8, BQN21, BN5 và QND8 có khả năng phân hủy 67, 73, 75 và 68 % DO với hàm lượng ban đầu là 39 g/l. Trong khi đó, hiệu suất của màng sinh học tạo thành bởi hỗn hợp các chủng này khi không có chất mang biochar trấu và khi có chất mang biochar trấu lần lượt là 78 và 98 %. Còn sử dụng chất mang biochar trấu không có vi sinh vật làm đối chứng thì thu được hiệu suất hấp phụ DO là 23 %. Như vậy, kết quả này mở ra tiềm năng ứng dụng biochar trấu làm chất mang cho các chủng vi khuẩn tạo màng sinh học để nâng cao hiệu quả xử lý ô nhiễm dầu

Mesoporous LaFeO3: Synergistic Effect of Adsorption and Visible Light Photo-Fenton Processes for Phenol Removal from Refinery Wastewater

Mesoporous LaFeO3 as a visible light-driven photocatalyst was prepared by a nanocasting method using mesoporous silica (SBA-15) as a hard template. The as-prepared LaFeO3 photocatalyst was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), N2 adsorption-desorption, X-ray photoelectron spectroscopy (XPS), and optical absorption spectra. The characterization studies and experimental results showed that LaFeO3 with porous structure caused by the removal of SBA-15 hard template could enhance the specific surface area of the resulting photocatalyst, which improves the phenol adsorption ability of the photocatalyst and in turn enhances its photo-Fenton catalytic activity. The photo-Fenton catalytic activity of the photocatalyst was investigated by photo-Fenton degradation of aqueous phenol under visible light irradiation. The effects of catalyst dosage, H2O2 concentration, and solution pH on the photo-Fenton catalytic degradation of phenol using mesoporous LaFeO3 were studied and optimized. Under the optimal conditions of 20 mg L−1 phenol, 1.0 g L−1 catalyst, and 10 mM H2O2 at pH = 5, the photo-Fenton degradation of phenol (93.47%) was achieved in 180 min under visible light irradiation. Furthermore, our results proved the stability and reusability of mesoporous LaFeO3 and revealed its catalytic mechanism for the photo-Fenton degradation of phenol

The Interactions among the Heavy Metals in Soils and in Weeds and Their Antioxidant Capacity under the Mining Activities in Thai Nguyen Province, Vietnam

In this study, the relationship between heavy metals (HMs) concentrations in soils and several weeds including Cyclosorus parasiticus, Dicranopteris linearis, Pityrogramma calomelanos, and Pteris vittata in three mining sites (Cam Gia (Thai Nguyen city), Tan Long (Dong Hy district), and Ha Thuong (Dai Tu district)) in Thai Nguyen province, Vietnam, have been investigated. The levels of HMs varied among soil origins and showed the contaminations of As, Cu, and Pb in soil samples collected in Dong Hy and Dai Tu districts. In addition, the HM distribution and cocontamination phenomena in different soils significantly affected the HM residues and transportation abilities into different species as well as tissues. Moreover, based on the analysis of bioaccumulation factor (BF) and translocation factor (TF), C. parasiticus and D. linearis were found potentially for phytoextraction by roots, while P. calomelanos and P. vittata were suitable for hyperaccumulation in shoots and leaves. Consequently, the strongest antioxidant property by 1,1-diphenyl-2-picrylhydrazyl (DPPH) and superoxide anion (SRSA) radical scavenging assays were demonstrated in the methanol root extracts of C. parasiticus and P. vittata, respectively. In conclusion, the correlation among HM in soils and tissues with antioxidant property allows us to hypothesize that the presence of these elements can enhance the antioxidant activity of plant extracts, suggesting to apply the weeds in phytoremediation as well as in phytomedicine

High biocompatible FITC-conjugated silica nanoparticles for cell labeling in both in vitro and in vivo models

Abstract Fluorescence nanosilica-based cell tracker has been explored and applied in cell biological research. However, the aggregation of these nanoparticles at physiological pH is still the main limitation. In this research, we introduced a novel fluorescence nano-based cell tracker suitable for application in live cells. The silica-coated fluorescein isothiocyanate isomer (FITC-SiO2) nanoparticles (NPs) were modified with carboxymethylsilanetriol disodium salt (FITC-SiO2-COOH), integrating the dianion form of FITC molecules. This nanosystem exhibited superior dispersion in aqueous solutions and effectively mitigated dye leakage. These labeled NPs displayed notable biocompatibility and minimal cytotoxicity in both in vitro and in vivo conditions. Significantly, the NPs did not have negative implications on cell migration or angiogenesis. They successfully penetrated primary fibroblasts, human umbilical vein endothelial cells and HeLa cells in both 2D and 3D cultures, with the fluorescence signal enduring for over 72 h. Furthermore, the NP signals were consistently observed in the developing gastrointestinal tract of live medaka fish larvae for extended periods during phases of subdued digestive activity, without manifesting any apparent acute toxicity. These results underscore the promising utility of FITC-SiO2-COOH NPs as advanced live cell trackers in biological research

Prevalence of Vibrio parahaemolyticus Causing Acute Hepatopancreatic Necrosis Disease of Shrimp in Shrimp, Molluscan Shellfish and Water Samples in the Mekong Delta, Vietnam

A total of 481 samples, including 417 shrimp and molluscan shellfish samples from retail shops and farms and 64 water samples from shrimp and molluscan shellfish farms in the Mekong Delta located the southern part of Vietnam, were examined for the presence of Vibrio parahaemolyticus (VpAHPND) caused acute haepatopancreatic necrosic disease (AHPND) in shrimp. VpAHPND strains were isolated in two of 298 (0.7%) molluscan shellfish samples from retail shops, seven of 71 (9.9%) shrimp samples from shrimp ponds, and two of 42 (4.8%) water samples from shrimp ponds. VpAHPND strains were classified into two types of O antigen, including O1 and O3, in which O1 was the predominant. VpAHPND strains isolated showed high resistance rates to colistin (100%), ampicillin (93.8%), and streptomycin (87.5%). These results indicate that VpAHPND is widely prevalent in environment in the Mekong Delta, Vietnam