Study on the effect of processing methods on the total polyphenol, 2,3,5,4’-tetrahydroxystilben-2-O-β-D-glucoside, and physcion contents in Fallopia multiflora Thunb. Haraldson root

This study investigated the changes in the ingredients in Fallopia multiflora Thunb. Haraldson (FMT) root after processing it with different methods such as soaking, stewing, and steaming or combined methods. The total polyphenol, 2,3,5,4′-tetrahydroxystilben-2-O-β-D-glucoside (THSG), and physcion contents in FMT products after processing were determined using high-performance liquid chromatography (HPLC) and ultraviolet-visible (UV-VIS) methods. The results demonstrated that the processing method and time significantly affected the contents of polyphenol, THSG, and physcion. The physcion and total polyphenol content increased or decreased during processing depending upon the processing time, while the THSG content gradually decreased with an increase in the processing time. The content of physcion (a substance that can cause liver toxicity) was analysed, and the suitable conditions for processing of the FMT products were determined as initial soaking in rice swill for 24 h and subsequent stewing with black beans and water for 12 h

Phenolic glucosides from the leaves of Desmodium gangeticum (L.) DC

From the water-soluble extract of the leaves of Desmodium gangeticum, three phenolic glucosides were isolated. By means of spectroscopic methods they were identified as methyl salicylate β-D-glucopyranoside (1), leonuriside A (2) and syringaresinol-4'-O-β-D-glucopyranoside (3). These compounds were isolated for the first time from the genus Desmodium. Compound 1 significantly inhibited a-glucosidase in comparison with diabetic drug acarbose

Equality in Online Education during COVID-19: Challenging the Educational Needs of Ethnic Minority Students in Vietnam

[Purpose] This study analyzes the inequalities of ethnic minority children to adapt to online education. This is also a challenge to the whole education system in Vietnam before the 4th COVID-19 outbreak is considered to have a serious impact on the economy and society of Vietnam. [Methodology/Approach/Design] A case study is conducted in a cross-sectional form with 50 high school students and 10 teachers of the boarding ethnic minority school in Nam Pu district, Dien Bien province of Vietnam. Questions were conducted for students, teachers, and school administrators. [Findings] The lack of WiFi catchers such as laptops, tablets, and smartphones along with poor infrastructure are the main factors affecting the effectiveness of online learning. [Practical Implications] Equality in education is the sustainable development goal adopted by the United Nations in 2015. Geographical differences and economic conditions are factors that directly impact the effectiveness of students' online learning in the context of COVID-19 19. The Government of Vietnam should have an effective financial policy to provide connectivity for poor students, reducing the gap in access to general education services for online classes that are ethnic minorities.[Purpose] This study analyzes the inequalities of ethnic minority children to adapt to online education. This is also a challenge to the whole education system in Vietnam before the 4th COVID-19 outbreak is considered to have a serious impact on the economy and society of Vietnam. [Methodology/Approach/Design] A case study is conducted in a cross-sectional form with 50 high school students and 10 teachers of the boarding ethnic minority school in Nam Pu district, Dien Bien province of Vietnam. Questions were conducted for students, teachers, and school administrators. [Findings] The lack of WiFi catchers such as laptops, tablets, and smartphones along with poor infrastructure are the main factors affecting the effectiveness of online learning. [Practical Implications] Equality in education is the sustainable development goal adopted by the United Nations in 2015. Geographical differences and economic conditions are factors that directly impact the effectiveness of students' online learning in the context of COVID-19 19. The Government of Vietnam should have an effective financial policy to provide connectivity for poor students, reducing the gap in access to general education services for online classes that are ethnic minorities.[Purpose] This study analyzes the inequalities of ethnic minority children to adapt to online education. This is also a challenge to the whole education system in Vietnam before the 4th COVID-19 outbreak is considered to have a serious impact on the economy and society of Vietnam. [Methodology/Approach/Design] A case study is conducted in a cross-sectional form with 50 high school students and 10 teachers of the boarding ethnic minority school in Nam Pu district, Dien Bien province of Vietnam. Questions were conducted for students, teachers, and school administrators. [Findings] The lack of WiFi catchers such as laptops, tablets, and smartphones along with poor infrastructure are the main factors affecting the effectiveness of online learning. [Practical Implications] Equality in education is the sustainable development goal adopted by the United Nations in 2015. Geographical differences and economic conditions are factors that directly impact the effectiveness of students' online learning in the context of COVID-19 19. The Government of Vietnam should have an effective financial policy to provide connectivity for poor students, reducing the gap in access to general education services for online classes that are ethnic minorities.[Purpose] This study analyzes the inequalities of ethnic minority children to adapt to online education. This is also a challenge to the whole education system in Vietnam before the 4th COVID-19 outbreak is considered to have a serious impact on the economy and society of Vietnam. [Methodology/Approach/Design] A case study is conducted in a cross-sectional form with 50 high school students and 10 teachers of the boarding ethnic minority school in Nam Pu district, Dien Bien province of Vietnam. Questions were conducted for students, teachers, and school administrators. [Findings] The lack of WiFi catchers such as laptops, tablets, and smartphones along with poor infrastructure are the main factors affecting the effectiveness of online learning. [Practical Implications] Equality in education is the sustainable development goal adopted by the United Nations in 2015. Geographical differences and economic conditions are factors that directly impact the effectiveness of students' online learning in the context of COVID-19 19. The Government of Vietnam should have an effective financial policy to provide connectivity for poor students, reducing the gap in access to general education services for online classes that are ethnic minorities

Enhancing Crop Yield Prediction Utilizing Machine Learning on Satellite-Based Vegetation Health Indices

Accurate crop yield forecasting is essential in the food industry’s decision-making process, where vegetation condition index (VCI) and thermal condition index (TCI) coupled with machine learning (ML) algorithms play crucial roles. The drawback, however, is that a one-fits-all prediction model is often employed over an entire region without considering subregional VCI and TCI’s spatial variability resulting from environmental and climatic factors. Furthermore, when using nonlinear ML, redundant VCI/TCI data present additional challenges that adversely affect the models’ output. This study proposes a framework that (i) employs higher-order spatial independent component analysis (sICA), and (ii), exploits a combination of the principal component analysis (PCA) and ML (i.e., PCA-ML combination) to deal with the two challenges in order to enhance crop yield prediction accuracy. The proposed framework consolidates common VCI/TCI spatial variability into their respective subregions, using Vietnam as an example. Compared to the one-fits-all approach, subregional rice yield forecasting models over Vietnam improved by an average level of 20% up to 60%. PCA-ML combination outperformed ML-only by an average of 18.5% up to 45%. The framework generates rice yield predictions 1 to 2 months ahead of the harvest with an average of 5% error, displaying its reliability

Comparison of sensory characteristics of green tea in Thai Nguyen and Phu Tho, Vietnam

Green tea is a popular consumption product in Vietnam. Especially, tea which origins from Tan Cuong, Thai Nguyen has been known for long by its better quality than those coming from other regions on the country. The study aims at comparing and finding out if the difference between tea in Thai Nguyen and Phu Tho can be figured by sensory tasting. Two products picked from Tan Cuong, Thai Nguyen province and two others from Phu Ho district, Phu Tho are were evaluated by a panel of twelve judges (eleven women and one man) who was set from a group of thirty eight peoples, had completed a general training and sensory tasting on tea. The experiment on dry tea (eleven descriptors) was carried out separately of the experiment on brewed tea (twenty-one descriptors) and brewed leaf (five descriptors). All attributes are made notes on the sensory unstructured intensity scale. Statistic analyses have shown typical differences by region among all of trees groups of attributes: dry leaf (10/11 attributes), liquor (6/21 attributes) and brewed leaf (5/5 attributes)

Novel exopolysaccharide produced from fermented bamboo shoot-isolated Lactobacillus fermentum

This study aimed at providing a route towards the production of a novel exopolysaccharide (EPS) from fermented bamboo shoot-isolated Lactobacillus fermentum. A lactic acid bacteria strain, with high EPS production ability, was isolated from fermented bamboo shoots. This strain, R-49757, was identified in the BCCM/LMG Bacteria Collection, Ghent University, Belgium by the phenylalanyl-tRNA synthetase gene sequencing method, and it was named Lb. fermentum MC3. The molecular mass of the EPS measured via gel permeation chromatography was found to be 9.85 × 104 Da. Moreover, the monosaccharide composition in the EPS was analyzed by gas chromatography–mass spectrometry. Consequently, the EPS was discovered to be a heteropolysaccharide with the appearance of two main sugars—D-glucose and D-mannose—in the backbone. The results of one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance spectroscopy analyses prove the repeating unit of this polysaccharide to be [→6)-β-D-Glcp-(1→3)-β-D-Manp-(1→6)-β-D-Glcp-(1→]n, which appears to be a new EPS. The obtained results open up an avenue for the production of novel EPSs for biomedical applications

Silicon quantum-dots-based optical probe for fluorometric detection of Cr6+ ions

In this report, silicon quantum dots (SiQDs) with the NH2 functional group were synthesized with the hydrothermal method. The as-prepared SiQDs exhibit a strong fluorescence emission peak               at 441 nm when excited at 355 nm and are effectively quenched upon adding Cr6+ ions. Hence, SiQDs were used as an optical probe to detect Cr6+ ions in solutions. The crystal structure of SiQDs was characterized by using X-ray diffraction (XRD). The Fourier-transform infrared spectroscopy (FT-IR) was used to determine the linker groups on the SiQDs surface. The fluorescence spectroscopic technique with an excitation wavelength of 355 nm was used to quantify the Cr6+ ion concentration in the solutions in the range of 0.1–1000 µM. Competition from common coexisting ions, such as K+, Na+, Al3+, Zn2+, and Pb2+, was ignorable. The test with actual samples showed good linearity for the Cr6+ concentration range of 0.1–50 µM

EVALUATION OF THE VULNERABILITY OF THE COASTAL SOCIO-NATURAL SYSTEMS (EXAMPLE FROM KHANH HOA COASTAL ZONE)

Joint Research on Environmental Science and Technology for the Eart

Chemical constituents and biological activities of Balanophora fungosa varietas globosa growing in Vietnam, as well as comparative chromatography with some species of the genus Balanophora J. R. & G. Forst

The chemical composition and biological activities of Balanophora fungosa var. globosa (BFG) were studied for the first time. Also, the chemical composition of some other Balanophora species was established for comparison. Phenolic compounds isolariciresinol, gallic acid, pinoresinol, methyl caffeate, and epipinoresinol-4-O-β-D-glucopyranoside were isolated from Balanophora fungosa var. globosa collected in Vietnam and identified by the NMR analysis. Some in vitro biological activities of the isolated compounds, including the inhibitory effect on NO production and cytotoxic effects, were evaluated. The chromatographic methods were developed to determine the chemical fingerprints of BFG and its very close taxon subsp. indica (Arn.) B. Hansen (BFI), also of the two new species recently recorded for the flora of Vietnam Balanophora tobiracola Makino (BT) and Balanophora subcupularis P.C. Tam (BS). Among the isolated compounds, isolariciresinol showed a moderate inhibitory effect on NO production (I% = 56.02 at concentration of 100 µg/mL), while gallic acid at concentration of 100 μg/mL demonstrated moderate cytotoxicity against cancer cell lines MCF-7 (human breast carcinoma) and PC3 (human prostate gland carcinoma). The HPTLC analysis showed similarities in the chemical compositions of BFG and BFI, as well as the difference between their compositions and these of BT and BS. O-caffeoyl-O-galloyl-glucoside I, caffeic acid glucoside, O-caffeoyl-di-galloyl-β-D-glucoside V, and 1-O-caffeoyl-3-O-galloyl-4,6-HHDP-β-D-glucoside as principal compounds were identified among 31 phenolic substances of BFI and BFG by using HPLC-MS/MS

INFLUENCES OF SOME HUMAN ACTIVITIES ON THE COASTAL ENVIRONMENT OF THAI BINH PROVINCE, VIETNAM

Joint Research on Environmental Science and Technology for the Eart