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- PublicationCircular economy approach for wastewater treatment farming in Bangpakong River basin(2020-12-09) N. Surinkul; S. Threedeach; W. Chiemchaisri; C. Chiemchaisri; Kasetsart University; Mahidol University; Suan Dusit University© 2020 Published under licence by IOP Publishing Ltd. Bangpakong River is one of river basins that faced the pollution problem in Thailand. This river is located in the downstream of central pain of Thailand and flows into the sea at the gulf of Thailand. Water quality problems in the last decade of this river basin are appeared from the low water quality index with evidences such as dead of fish, black color of water, low Dissolved Oxygen (DO) concentrations, high organics and nutrients concentrations, high contaminated of coliform bacteria. All wastewater is controlled by the environmental law. Only wastewater from agriculture part is not yet properly managed. The objective of this study was to quantify the mass and material flows in agricultural farms such as pig, fish and prawn farms. Circular economy concept as reuse of wastewater in agricultural farms was approached in scenario. Surveys, questionnaires and water samplings were taken for farms. Information and mass flows within the farms were analyzed. This study found that the main source of pollution from these farms mostly resulted from the effluent of wastewater in term of Biological Oxygen Demand (BOD) and Total Nitrogen (TN) loads, were discharged into the environment. The hot spot areas were canals which flow to the river. Mass flows in pig farm revealed that BOD and TN loads to the environment were 90, and 120 tons/year. In which, calculated thresholds were 30 and 60 tons/year for BOD and TN. Similar results also found from aquaculture farms which contributes BOD and TN loads of 187 and 77 tons/year for fish farms and 156 and 84 tons for prawn farms. In this study, calculated reuse as circular economy approach about 50% of farm wastewater to agricultural field could provide the key role of BOD and TN reduction to the environment, and meeting the threshold level.
- PublicationChitin and Chitosan Derivatives as Biomaterial Resources for Biological and Biomedical Applications(2020-12-16) Saravut Satitsri; Chatchai Muanprasat; Mahidol UniversityChitin is a long-chain polymer of N-acetyl-glucosamine, which is regularly found in the exoskeleton of arthropods including insects, shellfish and the cell wall of fungi. It has been known that chitin can be used for biological and biomedical applications, especially as a biomaterial for tissue repairing, encapsulating drug for drug delivery. However, chitin has been postulated as an inducer of proinflammatory cytokines and certain diseases including asthma. Likewise, chitosan, a long-chain polymer of N-acetyl-glucosamine and d-glucosamine derived from chitin deacetylation, and chitosan oligosaccharide, a short chain polymer, have been known for their potential therapeutic effects, including anti-inflammatory, antioxidant, antidiarrheal, and anti-Alzheimer effects. This review summarizes potential utilization and limitation of chitin, chitosan and chitosan oligosaccharide in a variety of diseases. Furthermore, future direction of research and development of chitin, chitosan, and chitosan oligosaccharide for biomedical applications is discussed.
- PublicationThe experiential learning unit for promoting students’ understanding of vapor pressure and related concepts(2020-01-01) Siwa Mahardthai; Supan Yodyingyong; Namkang Sriwattanarothai; Piyachat Jittam; Mahidol University© 2020, Springer Nature Singapore Pte Ltd. Vapor pressure is a difficult concept for high school students because it requires understanding at the microscopic level. To better understand the concept, students should clearly understand some prerequisite concepts, such as evaporation, condensation, and pressure. Therefore, this research aims to develop Kolb’s experiential learning activities for providing experience before extending to learn the vapor pressure concept through online resources. The learning unit consists of two main activities that are 1) observing scientific phenomena aims at helping students to gain experience of the concepts, and 2) color manipulatives designing to help students to understand the concepts at the microscopic level. The learning unit had been implemented with grade ten students. The conceptual test and interview had been used to assess student understanding. Results show that some students still have learning difficulties related to vapor pressure and related concepts. They had difficulty in explaining the concepts at the molecular explanation and confused some technical terms. The online resources have been discussed for suggesting a suitable pathway to each group of students.
- PublicationA preliminary result of lamtakong embankment dam safety assessment using integrated subsurface electrical resistivity and shear wave velocity model(2020-01-01) P. Amatyakul; K. Phueak-Im; P. Morhrasi; T. Suklim; Mahidol University; Royal Irrigation Department; Science© EAGE 2020. Clustering model using integrated subsurface electrical resistivity and shear wave velocity model provides conspicuously subsurface structure of the Lamtakong embankment dam as show in Fig 1. Furthermore, the Anomaly is found in manual method located around elevation at 250 meters, and distance at 250 meters. The resistivity and velocity of the anomaly are low, so that can be interpreted as a possible leakage and internal erosion zone of the Lamtakong embankment dam. The anomaly is located at the foundation of the dam. Incidentally, the automatic method developed by fuzzy c-means clustering algorithm and selected center method is incomplete. In future study, considering other factors may develop the data grouping of automatic method such as engineer factor.
- PublicationTlr4/md-2 is a receptor for extracellular nucleophosmin 1(2020-02-01) Kota Nakatomi; Hikari Ueno; Yuto Ishikawa; Ronny Christiadi Salim; Yuki Mori; Issey Kanemoto; Salunya Tancharoen; Kiyoshi Kikuchi; Naoki Miura; Taketo Omori; Emiko Okuda-Ashitaka; Kiyoshi Matsumura; Hitoshi Imaizumi; Yoshihiro Motomiya; Ikuro Maruyama; Ko Ichi Kawahara; Kagoshima University Graduate School of Medical and Dental Sciences; Osaka Institute of Technology; Kagoshima University; Mahidol University; Tokyo Medical University; Kurume University School of Medicine; Suiyukai Clinic© 2020, Spandidos Publications. All rights reserved. Nucleophosmin 1 (NPM1) primarily localizes to the nucleus and is passively released into the extracellular milieu by necrotic or damaged cells, or is secreted by monocytes and macrophages. Extracellular NPM1 acts as a potent inflammatory stimulator by promoting cytokine production [e.g., tumor necrosis factor-α (TNF-α)], which suggests that NPM1 acts as a damage-associated molecular pattern. However, the receptor of NPM1 is unknown. Evidence indicates that DAMPs, which include high mobility group box 1 and histones, may bind Toll-like receptors (TLRs). In the present study, it was shown that NPM1 signaling was mediated via the TLR4 pathway, which suggests that TLR4 is an NPM1 receptor. TLR4 binds myeloid differentiation protein-2 (MD-2), which is essential for intracellular signaling. Furthermore, the TLR4 antagonist, LPS-Rhodobacter sphaeroides (an MD-2 antagonist) and TAK-242 (a TLR4 signaling inhibitor) significantly inhibited NPM1-induced TNF-α production by differentiated THP-1 cells as well as reducing ERK1/2 activation. Far-western blot analysis revealed that NPM1 directly bound MD-2. Thus, the results of the present study provide compelling evidence that TLR4 binds NPM1, and it is hypothesized that inhibiting NPM1 activity may serve as a novel strategy for treating TLR4-related diseases.
- PublicationEffect of different combinations of NAA and TDZ for shoot induction in vitro culture of Aglaonema simplex (Blume) Blume(2020-12-08) S. Soontornyatara; P. Klammorn; Mahidol University© 2020 International Society for Horticultural Science. All rights reserved. Wan Khanmak (Aglaonema simplex (Blume) Blume) is a kind of Thai herb. The ripe fruits are extensively used as longevity enhancer and anti-asthma medication, but the number of fruits plant-1was only 3-14. This research project aims to find the most appropriate tissue culture protocol for mass propagation of Wan Khanmak herb. The experimental design was completely randomized design (CRD). The axillary buds of Wan Khanmak were incubated on MS medium supplemented with 1-naphthaleneacetic acid (NAA) and thidiazuron (TDZ) at various doses; 0:0, 0.25:0.5, 0.25:1.0, 0.25:1.5, 0.25:2.0 and 0.25:2.5 mg L-1. The results showed that the most effective medium was MS medium supplemented with NAA and TDZ at 0.25:2.5 mg L-1ratio which produced the highest number of average shoots per culture (4.49 shoots) with an average shoots length 1.60 cm in 8 weeks of culture. This treatment gave the fastest time to produce the first shoot in 8.5 days.
- PublicationAn Investigation of the Relationship Among Medical Center’s Image, Service Quality, and Patient Loyalty(2020-01-01) Chanchai Phonthanukitithaworn; Phaninee Naruetharadhol; Nathatenee Gebsombut; Raoyrin Chanavirut; Wanwipada Onsa-ard; Pawanrut Joomwanta; Zou Chanyuan; Chavis Ketkaew; Khon Kaen University; Mahidol University© The Author(s) 2020. This research aimed to study significant relationships among factors influencing customer satisfaction and loyalty in the health care service industry. In order to test the conceptual framework, structural equation modeling (SEM) was used to analyze the data from 252 respondents (outpatients) at four public and private hospitals in Khon Kaen City, Thailand. This empirical research determined how the health care service image, service quality, and behavioral intentions were interrelated using a scale adapted from Taiwan Customer Satisfaction and American Customer Satisfaction Indices, as the perceived quality variable was designated as a second-order construct. The findings showed that the significant factor impacting customer loyalty is customer satisfaction. Corporate image significantly enhanced both customer expectations (CEs) and perceived service quality. The researchers also observed that perceived service quality was positively related to tangibility, instrumental, and emotional supports in addition to customer satisfaction. In conclusion, this article proposed a thoughtful research scenario for management and corporate/public policymakers at the national level in Thailand. It was observed that a good image could directly enhance perceived service quality for businesses in the health service sector. Short Abstract: We aimed to explore the relationship between image, service quality, and patient loyalty in the health service sector. A multivariate analysis (structural equation modeling) was employed to analyze the data from 252 outpatients in Khon Kaen City, Thailand. The conventional service quality model suggests that corporate image influences customer expectation, and then affects perceived service quality, then customer satisfaction, and finally, loyalty. However, this article found that, in the health service sector, a corporate image may directly influence perceived service quality without the customer expectation variable as a mediator.
- PublicationMobile learning technology in STEM education: A systematic review from 2010 to 2019(2020-11-23) Wacharaporn Khaokhajorn; Prapawan Thongsri; Patcharin Panjaburee; Niwat Srisawasdi; Sakon Nakhon Rajabhat University; Khon Kaen University; Mahidol UniversityCopyright © 2020 Asia-Pacific Society for Computers in Education. Mobile technology could support students' learning in anytime and anywhere. It led to mobile learning principle, which has been recognized as pedagogy to support the learning of Science, Technology, Engineering, and Mathematics (STEM). Recently, there is less systematic analysis to reveal trend of mobile learning in STEM education. This paper conducted a metareview of the studies published in academic journals, indexed by Scopus, from 2010 to 2019 to analyze years, nationalities, and subject areas emphasizing the pedagogy and technology of mobile learning in STEM education. The results revealed that the application of mobile learning technology in STEM disciplines have been increased in the past decade. In addition, the review articles reported subject areas in social science has the highest number of using mobile technology in STEM learning. The findings of this study encourage more educational research in the area of mobile learning technology in STEM education.
- PublicationWhole-genome sequence analysis and comparisons between drug-resistance mutations and minimum inhibitory concentrations of Mycobacterium tuberculosis isolates causing M/XDR-TB(2020-12-01) Ditthawat Nonghanphithak; Orawee Kaewprasert; Pratchakan Chaiyachat; Wipa Reechaipichitkul; Angkana Chaiprasert; Kiatichai Faksri; Khon Kaen University; Faculty of Medicine, Siriraj Hospital, Mahidol University© 2020 Nonghanphithak et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Drug resistance (DR) remains a major challenge for tuberculosis (TB) control. Whole-genome sequencing (WGS) provides the highest genetic resolution for genotypic drug-susceptibility tests (DST). We compared DST profiles of 60 Mycobacterium tuberculosis isolates which were drug resistant according to agar proportion tests (one poly DR-TB, 34 multidrug-resistant TB and 25 extensively drug-resistant TB). We additionally performed minimum inhibitory concentration (MIC) tests using Sensititre MYCOTBI plates (MYCOTB) and a WGS-based DST. Agreement between WGS-based DST and MYCOTB was high for all drugs except ethambutol (65%) and ethionamide (62%). Isolates harboring the -15 c/t inhA promoter mutation had a significantly lower MIC for isoniazid than did isolates with the katG Ser315Thr mutation (p < 0.001). Similar patterns were seen for ethambutol (embB Gly406Asp vs. embB Met306Ile), streptomycin (gid Gly73Ala vs. rpsL Lys43Arg), moxifloxacin (gyrA Ala90Val vs. gyrA Asp94Gly) and rifabutin (rpoB Asp435Phe/Tyr/Val vs. rpoB Ser450Leu). For genotypic heteroresistance, isolates with lower proportion of mapped read tended to has lower MIC of anti-TB drugs than those with higher proportion. These results emphasize the high applicability of WGS for determination of DR-TB and the association of particular mutations with MIC levels.
- PublicationTechno-economic assessment of a biomass torrefaction plant for pelletized agro-residues with flue gas as a main heat source(2020-12-01) Thossaporn Onsree; Chawannat Jaroenkhasemmeesuk; Nakorn Tippayawong; Mahidol University; Chiang Mai University© 2020 The Authors Torrefaction combined with densification for upgrading biomass to torrefied biomass pellets is increasingly of great interest since torrefied biomass pellets are considered as a major renewable energy source. Especially in the application of co-firing with coal, torrefaction may be easily integrated into an existing co-firing power plant, whose flue gases from the power plant could be used to torrefy biomass pellets. This could also help to improve the overall carbon efficiency of the power plant and reduce emissions of greenhouse gases. In the present work, a torrefaction plant for corn residue pellets to produce torrefied solid fuels using flue gases as a main heat source was simulated in Aspen Plus® software. Torrefaction module was successfully modelled by an RYield reactor, which was programmed with the two-steps-in-series kinetic for the decomposition of biomass pellets as well as the volatile formation for by-products. The model can, therefore, provide the distribution and yield of both torrefied biomass pellets and volatile by-products. From the validation, the simulation results appeared to show good agreement with available experimental data in the literature. At the suggested conditions of 260 °C wet flue gas and 20 min residence time, thermal energy of 460 J/g and 380 J/g were required for the drying and the torrefaction modules, respectively. At these conditions, the performance of the whole process was found to be almost 95%. This plant produced 75% w/w torrefied biomass pellets yield with HHV of 21.9 MJ/kg. The by-products mainly included 10.7% w/w water, 7.4% w/w CO2, and 1.7% w/w CO. Our findings provide a feasible outlook for integrating a torrefaction process of biomass pellets into a co-firing power plant, utilizing a realistic heat of waste flue gases for the process.