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Thuan Chau is a serious district affected by forest fire in Vietnam, especially in 2016; however, no forest fire prediction research has been conducted for this region. Thus, knowledge of spatial patterns of fire danger of the district plays a key role in forest succession and ecological implications. This study's aim was to analyze the spatial pattern of fire danger for the tropical forest of Thuan Chau district using advanced machine learning algorithms, Support Vector Machine classifier (SVMC), Random Forests (RF), and Multilayer Perceptron Neural Network (MLP-Net). For this purpose, a GIS database for the study area was established with 564 forest fire locations and ten forest fire variables. Then, Pearson correlation method was used to assess the correlation of the variables with the forest fire. In the next step, three forest fire danger models, SVMC, RF, and MLP-Net, were trained and validated. Finally, global performance of these models was assessed using the classification accuracy (ACC), Kappa statistics (KS), Area under the curve (AUC). In addition, Wilcoxon signed-rank test was employed to check the prediction performance of these models. The result shows the three models performed well; however, the MLP-Net model has the highest prediction performance (ACC = 81.7, KS = 0.633, and AUC = 0.894), followed by the RF model (ACC = 81.1, KS = 0.621, and AUC = 0.883), and the SVMC model (ACC = 80.2, KS = 0.604, and AUC = 0.867). The result in this study is useful for the local authority and forest manager in forest management and fire suppression. [ABSTRACT FROM AUTHOR]

Because bla CTX-M is responsible for resistance of bacteria to the third generation cephalosporins, location of bla CTX-M could be a good indicator for classifying bacterial isolates harboring bla CTX-M in molecular epidemiology. However, determination of bla CTX-M location has been difficult when multiple copies of IS Ecp1 were found on bacterial genome. We aimed to establish a high-throughput analytical method for upstream genetic structures (UGS) of IS Ecp1 to facilitate determination of bla CTX-M location. Extracted DNA samples obtained from 168 Escherichia coli isolates possessing bla CTX-M were digested by restriction enzyme, HaeIII, and the digested DNA fragments were ligated with homemade barcode adaptors. Then, DNA fragments containing UGS of IS Ecp1 were amplified and subjected to the Nanopore sequencer. Nucleotide sequences and locations of 168 UGSs obtained from the examined E. coli isolates were determined. Among the 168 determined UGSs, 150 (89.3%) UGS were confirmed on plasmid and classified into eight types. Interestingly, coding sequence of IS Ecp1 transposase gene in seven of the eight types were disrupted by IS 26 insertion. The remaining 18 (10.7%) UGSs were observed in identical chromosomal region. The obtained nucleotide sequences the locations of UGSs were confirmed by conventional capillary sequencer and Southern blotting, respectively, and any discrepant result was not observed with these confirmation procedures. Our results indicated that the established method was efficient for simultaneously determining at least 100 different UGS, and suggested that the determined UGSs of IS Ecp1 - bla CTX-M transposition unit was useful for classification of bacterial isolates harboring bla CTX-M. [ABSTRACT FROM AUTHOR]

• Potential edible, active packaging films were successfully fabricated based on chitosan and Sonneratia caseolaris (L.) Engl. leaves extract. • Hydrogen interaction between chitosan matrix and SCELE flavonoids decrease moisture content, swelling degree and water vapor permeation. • Thermal stability and mechanical behavior of the chitosan matrix was not affected considerably by the presence of 2 % SCELE. • A small amount of SCELE was found to remarkably improve antimicrobial activities of chitosan film against Pseudomonas aeruginosa. The purpose of this study is to prepare and characterize the potential edible packaging films based on chitosan and Sonneratia caseolaris (L.) Engl. leaf extract (SCELE) into matrix. The incorporation of SCELE into Chitosan matrix was conducted with various contents (1–3 % wt) and the chitosan-based film samples were investigated. The effects of SCELE on the physical properties and antimicrobial activity of samples were also characterized. The Vietnamese banana fruit was chosen for food preservation and the appearance of banana coated with and without chitosan-based composite films was evaluated. The results indicated that the presence of SCELE can improve the antimicrobial activities, water vapor barriers while a significant decrease in light transmittance was found. Furthermore, the tensile strength and thermal stability were not affected by the addition of 2 % wt SCELE. Bananas coated with composite film based on chitosan matrix and SCELE had longer life time than control sample and those coated with pure chitosan film, indicating that the combination of SCELE into chitosan matrix brings potential application for active edible food packaging. [ABSTRACT FROM AUTHOR]