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Enhanced Triacylglycerol Production In Chlorella Vulgaris By Flux Balance Analysis On Metabolic Network, Issalapap Kaothong Jan 2022

Enhanced Triacylglycerol Production In Chlorella Vulgaris By Flux Balance Analysis On Metabolic Network, Issalapap Kaothong

Chulalongkorn University Theses and Dissertations (Chula ETD)

Triacylglycerol (TAG) is a type of lipid that can be produced by a microalga called Chlorella vulgaris, which is a promising source of biodiesel. However, there is a lack of research and models explaining how to directly produce this lipid. To address this, we propose using linear minimization of metabolic adjustment (LMOMA), which predicts gene manipulation effects based on Flux Balance Analysis (FBA), to enhance TAG production. We conducted single-gene deletion experiments on the genome-scale metabolic model of C. vulgaris UTEX 395 (iCZ843) under different growth conditions: heterotrophy, photoautotrophy, and mixotrophy conditions. We found that the TAG production increased by …

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Comparative Analysis Of Mutational Landscapes Identified From Exome Sequencing Of Tumor Tissues And Circulating Tumor Dna, Julanee Leenanitikul Jan 2022

Comparative Analysis Of Mutational Landscapes Identified From Exome Sequencing Of Tumor Tissues And Circulating Tumor Dna, Julanee Leenanitikul

Chulalongkorn University Theses and Dissertations (Chula ETD)

Next-generation sequencing of circulating tumor DNA (ctDNA) has been used as a noninvasive alternative for cancer diagnosis and characterization of tumor mutational landscape. However, low ctDNA fraction and other factors can limit the ability of ctDNA analysis to capture tumor-specific and actionable variants. In this study, whole-exome sequencings (WES) were performed on paired ctDNA and tumor biopsy in 15 cancer patients to assess the extent of concordance between mutational profiles derived from the two source materials. We found that up to 16.4% ctDNA fraction can still be insufficient for detecting tumor-specific variants and that high concordance with tumor biopsy is …

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Catalytic Mechanism And Inhibition Of Plasmodium Sp. Serine Hydroxymethyltransferase By Computational Simulations, Pitchayathida Mee-Udorn Jan 2022

Catalytic Mechanism And Inhibition Of Plasmodium Sp. Serine Hydroxymethyltransferase By Computational Simulations, Pitchayathida Mee-Udorn

Chulalongkorn University Theses and Dissertations (Chula ETD)

Malaria has spread in many countries with a 12% increase in death cases after the COVID-19 pandemic. Over the Greater Mekong subregion, the clinical efficacy of antimalarial drugs has been reduced due to resistance. Target-based approaches on attractive drug targets, such as Plasmodium serine hydroxymethyltransferases (SHMTs) exhibiting distinct structure and function as well as kinetic mechanisms from the human enzyme homologue, are highly useful methods to be used for bypassing the present resistance in the field. In this study, the catalytic mechanism of Plasmodium SHMT was investigated following the retro-aldol proposed scheme by the combined quantum mechanics/molecular mechanics molecular dynamics …

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Computational Approaches For Identifying Bioactive Compounds Inhibiting Sars-Cov-2 Main Protease, Piyatida Pojtanadithee Jan 2022

Computational Approaches For Identifying Bioactive Compounds Inhibiting Sars-Cov-2 Main Protease, Piyatida Pojtanadithee

Chulalongkorn University Theses and Dissertations (Chula ETD)

The infectious disease caused by the novel coronavirus 2019 has devastatingly affected the global economy and society. However, the drug discovery process from concept to approval requires a significant investment of time and resources. To address these challenges, we employed structure-based virtual screening techniques, including drug-likeness screening, pharmacophore-based virtual screening, molecular docking, molecular dynamics simulation, and fragment molecular orbital calculation. The protein target of this investigation was the main protease or 3-chymotrypsin-like-protease (3CLpro) of the coronavirus, given its pivotal role in the viral replication process. Using our in-house database of natural products and their derivatives, we aimed to identify potent …

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Analysis Of Expression Patterns Of Brassinosteroid-Responsive Genes In Arabidopsis Root Using Single-Cell Rna Sequencing Datasets, Thanaporn Wongkham Jan 2022

Analysis Of Expression Patterns Of Brassinosteroid-Responsive Genes In Arabidopsis Root Using Single-Cell Rna Sequencing Datasets, Thanaporn Wongkham

Chulalongkorn University Theses and Dissertations (Chula ETD)

Brassinosteroid (BR) plays a complex role in root growth and development by regulating the expression of downstream target genes through the BR signaling pathway. In this scRNA-seq study of Arabidopsis roots, tissue- and developmental-specific roles of BR were identified. Atrichoblast, an epidermal cell that develops into a non-hair cell, displayed the highest enrichment of BR-induced genes in the elongation and maturation zones among all cell types. Trajectory analysis revealed distinct expression patterns of BR biosynthesis and signaling genes between atrichoblasts and trichoblasts. Atrichoblasts exhibited higher expression levels of BR biosynthesis genes (DET2 and ROT3) and BR signaling genes (BRI1 and …

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Whole Genome Sequencing, De Novo Assembly, And Comparative Analysis Of Varanus Salvator And Megaustenia Siamensis, Wanna Chetruengchai Jan 2022

Whole Genome Sequencing, De Novo Assembly, And Comparative Analysis Of Varanus Salvator And Megaustenia Siamensis, Wanna Chetruengchai

Chulalongkorn University Theses and Dissertations (Chula ETD)

Background: Understanding the animal genome structure and function is pivotal for expanding our current knowledge of evolution, biodiversity, cosmeceutical and medical applications. Each species has a unique characteristic feature. Varanus salvator is a reptile (vertebrate) prevalent in Thailand. It has evolved over millions of years to adapt and survive in urban environments, polluted canals, and garbage dumps. It still survives without noticeable effects. Megaustenia siamensis, an invertebrate, is famous for its ability to produce biological adhesive substances enabling it to stick to trees’ leaves even in heavy rain. However, there is very little genomics or transcriptomics data for V. salvator …

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Senescent White Blood Cells In Colorectal Carcinoma Patients, Khin Aye Thin Jan 2022

Senescent White Blood Cells In Colorectal Carcinoma Patients, Khin Aye Thin

Chulalongkorn University Theses and Dissertations (Chula ETD)

Colorectal cancer (CRC) and ageing can contribute to changes in immune cells including immuno-senescence. The objectives of the study were to determine if the senescence marker (p16INK4A) was expressed more at higher levels in peripheral white blood cells in CRC compared to age-matched healthy controls. Another aim was to determine the phenotypic changes of T cells, NK cells and monocytes during ageing and CRC in case-control studies. Cases were patients with CRC and controls were matched with cases based on age. Peripheral immune cells were analysed for p16INK4A using immunofluorescence and immunophenotypes were determined with flow cytometry. Correlation studies with …

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The T Cell Senescence In Breast Cancer, Sikrit Denariyakoon Jan 2022

The T Cell Senescence In Breast Cancer, Sikrit Denariyakoon

Chulalongkorn University Theses and Dissertations (Chula ETD)

Background: The cancer-immune cell crosstalk is a common immune-evasion mechanism of cancer. This crosstalk can result in epigenetic changes in immune phenotypes to accelerate tumor growth and metastasis. Senescent T lymphocytes are formed during T cell differentiation, and are recently described as one of the dysfunctional T cells in cancer. In breast cancer, estrogen does not only regulate normal physiology in females, but is also involved in cancer development and cancer treatment. It may also attenuate senescent phenotypes, and increase DNA damage in several cell-lines. This thesis therefore examined for the presence of senescent T lymphocytes in breast cancer patients, …

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Screening Of Clostridium Sp. For Biohydrogen Production From Synthetic Wastewater, Chonticha Srimawong Jan 2022

Screening Of Clostridium Sp. For Biohydrogen Production From Synthetic Wastewater, Chonticha Srimawong

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this work, bacteria that can produce endospores were isolated from natural sources and industrial wastes, including mangrove forests, hot springs, and coconut factories. The bacterial isolates were identified as Clostridium spp. and Panibacillus spp. based on 16S RNA gene. When comparing the H2 produced by batch fermentation, two of the isolates with the best H2 production were selected for further study, namely CUEA01 and CUEA03. After genomics analysis, it was discovered that CUEA01 is a novel species named C. hydrogenum, and CUEA03 is C. felsineum. Both are capable of growing and producing H2 in alkaline conditions. The genomics data …

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Screening Of Clostridium Sp. For Butanol Production From Sato (Thai Rice Wine) Factory Wastewater, Julalak Buranaprasopchai Jan 2022

Screening Of Clostridium Sp. For Butanol Production From Sato (Thai Rice Wine) Factory Wastewater, Julalak Buranaprasopchai

Chulalongkorn University Theses and Dissertations (Chula ETD)

The production of Sato, a Thai traditional beverage, yields Sato wastewater (STW), which contains residual rice constituents with high chemical and biological oxygen demands and so forms an environmental problem. In addition, STW often smells rotten from the formation of hydrogen sulfide. To solve this problem, the composition of STW was analyzed for its physiological and chemical characteristics to evaluate its potential as a substrate for ABE fermentation using Clostridium spp., which has never been reported for use in acetone-butanol-ethanol (ABE) fermentation before. Solvent-producing Clostridium isolates were obtained from environmental sources in Thailand, and that producing the highest butanol level …

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Identification And Application In Plant Of Plant Growth-Promoting Endophytic Bacteria, Kanchana Sitlaothaworn Jan 2022

Identification And Application In Plant Of Plant Growth-Promoting Endophytic Bacteria, Kanchana Sitlaothaworn

Chulalongkorn University Theses and Dissertations (Chula ETD)

Seventy-eight endophytic bacteria isolated from 15 plant samples in Thailand including 50 isolates from sugarcane root samples obtained from 6 Provinces and 28 isolates from stems and leaves of healthy plants in Kanchanaburi Province, were identified and evaluated for plant growth promoting capability using rice as a plant model. They were identified as Gluconacetobacter (37 isolates), Pantoea (14 isolates), Burkholderia (2 isolates), Pseudomonas (4 isolates), Priestia (4 isolates), Enterobacter (2 isolates), Acinetobacter (2 isolates), Novosphingobium (2 isolates), Curtobacterium (2 isolates), and each of Nguyenibacter, Aureimonas, Bacillus, Peribacillus, Sphingobium, Staphylococcus, Brevibacillus, Aneurinibacillus, and Pseudarthrobacter based on their phenotypic characteristics and 16S …

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Anti-Pathogenic Yeast Malassezia Globosa Activity By Propolis Of Stingless Bee Geniotrigona Thoracica, Kawisara Konsila Jan 2022

Anti-Pathogenic Yeast Malassezia Globosa Activity By Propolis Of Stingless Bee Geniotrigona Thoracica, Kawisara Konsila

Chulalongkorn University Theses and Dissertations (Chula ETD)

Malassezia globosa is a lipophilic pathogen which relates to various chronic skin diseases. Azole drugs are main available treatments, but they have been reported with many side effects and microbial drug resistance. Therefore, the alternative medications should be developed. As the antimicrobial activity of propolis is outstanding, this study aims to investigate the potential of propolis from stingless bee, Geniotrigona thoracica against the pathogenic yeast. The extraction and characterization of the propolis components were done after the obtained extracts were evaluated for anti-M. globosa growth by using agar well diffusion assay and broth microdilution assay. Moreover, Inhibitory Concentration values at …

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Antiproliferative Agents From Mushroom Phellinus Sp., Kulrut Pichayaphinyo Jan 2022

Antiproliferative Agents From Mushroom Phellinus Sp., Kulrut Pichayaphinyo

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this study, Phellinus powdered (600 g) was extracted with methanol and DI water. The methanolic crude extract of the mushroom was partitioned with hexane, dichloromethane, ethyl acetate and methanol respectively. All crude extracts were evaluated antiproliferative activity against lung cancer (A549) and neuroblastoma (SH-SY5Y) cell lines by MTT assay. It was found that the dichloromethane extract (CDE) exhibited the strongest antiproliferative activity with half maximal inhibitory concentration (IC50) values of 132.4 and 106.87 µg/mL against human lung cancer and neuroblastoma cell lines, respectively. The ethyl acetate extract (CEE) exhibited moderate antiproliferative activity with IC50 values of 138.64 and >250 …

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Combining Technical Analysis And Deep Learning Models For Stock Market Trading, Phurinut Pholsri Jan 2022

Combining Technical Analysis And Deep Learning Models For Stock Market Trading, Phurinut Pholsri

Chulalongkorn University Theses and Dissertations (Chula ETD)

The issuance of stocks constitutes a means by which ownership in a company is represented, and its distribution may vary depending on whether the company is limited or public. The stock market offers the potential for high returns, thereby serving as an attractive avenue for investment. Against this backdrop, the objective of this study is to develop a predictive model for stock prices that can facilitate profitable trading outcomes. To achieve this aim, the study focuses on intraday and hourly trading and utilizes a hybrid model that integrates Bidirectional Long Short-Term Memory (BiLSTM) and Convolutional Neural Network (CNN) architectures, along …

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Effects Of Lipids And Surfactants On The Characteristics Of Asiatic Acid-Loaded Solid Lipid Microparticles, Jatuporn Witarat Jan 2022

Effects Of Lipids And Surfactants On The Characteristics Of Asiatic Acid-Loaded Solid Lipid Microparticles, Jatuporn Witarat

Chulalongkorn University Theses and Dissertations (Chula ETD)

The objective of this study was to evaluate the effects of solid lipids: beeswax and cetyl alcohol, and surfactants: Tween 80®, soybean lecithin and poloxamer 188 on the characteristics of solid lipid microparticles containing asiatic acid (AASLM). The AASLM were prepared from 10% or 15% of beeswax or cetyl alcohol together with 3% of surfactant F1-F12) by melt dispersion cum freeze-drying technique to obtain a solid dosage form. The physicochemical characteristics of the AASLM powders, including appearance, surface morphology, particle size, %labeled amount of asiatic acid (AA) and %entrapment efficiency (EE) were evaluated. The results revealed that AASLM prepared from …

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A Learning And Development With Collaborative Note- Taking Model For Enhancing The Future Higher Education Students’ Workforce Skills In Socio-Emotional Regulation And Grit Based On A Web 5.0 Approach, Suthanit Wetcho Jan 2022

A Learning And Development With Collaborative Note- Taking Model For Enhancing The Future Higher Education Students’ Workforce Skills In Socio-Emotional Regulation And Grit Based On A Web 5.0 Approach, Suthanit Wetcho

Chulalongkorn University Theses and Dissertations (Chula ETD)

The multi-methods research and development (R&D) aim to: 1) investigate the socio-emotional regulation framework to promote higher education students' future workforce skills in social and emotional regulation and grit, 2) investigate how socio-emotional regulation impacts grit based on instructional technology via online social collaborative note-taking in the web 5.0, and 3) define the design principle on the implication of the instructional technology via online social collaborative note-taking to the web 5.0. In this study, 365 graduate students from multi-stage random sampling participated in the online survey, 5 experts and 11 graduate students with purposive selection participated in the design research …

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Online Self-Learning System For Prediabetes Patients, Ye Moe Myint Jan 2022

Online Self-Learning System For Prediabetes Patients, Ye Moe Myint

Chulalongkorn University Theses and Dissertations (Chula ETD)

This thesis implements a web-based application that combines a 3D learning center and educational game to facilitate the monitoring, management, and treatment of patients with prediabetes mellitus, by providing exercise plans and controlled diets. The application utilizes advanced web technologies, 3D modeling, and gamification principles to create an engaging learning experience. User-centered design ensures usability, and testing demonstrates positive outcomes, including increased knowledge, motivation, and engagement. This research contributes to digital health interventions by empowering prediabetes patients with informed decision-making and healthy habits. Future directions include expanding the application, refining the user interface, and evaluating long-term impact on prediabetes management.

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Effects Of The Writing Instructional Model With Integration Of Inquiry-Based Learning And Visual Literacy On 21st Century Skills Of Efl Learners, Patsawut Sukserm Jan 2022

Effects Of The Writing Instructional Model With Integration Of Inquiry-Based Learning And Visual Literacy On 21st Century Skills Of Efl Learners, Patsawut Sukserm

Chulalongkorn University Theses and Dissertations (Chula ETD)

Although a body of research illustrates the potential of inquiry-based learning in promoting the 21st century skills among English as a Foreign Language (EFL) students (AbuRezeq, 2018; Imansyan et al., 2019; Milatasari, 2013; Palupi et al., 2020; Tongjean et al., 2019), other studies have indicated its occasional failure in eliciting students’ engagement (Duschl & Wright, 1989; Gill, 2005), which affects students’ success in language learning. This results in the need to leverage other pedagogical strategies, including visual literacy, to increase the efficacy of inquiry-based learning (Gonzalez-Ledo, 2015; Maricimoi, 2017; Navidinia et al., 2018; Rokhaniyah, 2019, Sulastri, 2019; Tayib, 2015; Villasor, …

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Knowledge, Attitude And Practices On Potato Pest Management Of Ethnic Farmers In Southern Shan State, Myanmar, Pyae Pa Pa Aung Jan 2022

Knowledge, Attitude And Practices On Potato Pest Management Of Ethnic Farmers In Southern Shan State, Myanmar, Pyae Pa Pa Aung

Chulalongkorn University Theses and Dissertations (Chula ETD)

Potato is cultivated as the main tuber crop which is essential for ethnic farmers’ household income in Southern Shan State, Myanmar. Most ethnic farmers use chemical pesticides widely to enhance crop yield and to control pests in the farm. The use of chemical pesticides could lead to a series of health impacts of the farmers and environmental issues. The main aim of the study is to explore farmers’ knowledge, attitude and current farm practices on pest management in potato production. The participants of 100 farmers were chosen from each village with a cluster and purposive sampling technique using structured questionnaires …

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Comparison Of Volumetric Changes At Implant Connector Among Three Different Types Of Abutment After Cyclic Loading, Piyawan Jirayusakamol Jan 2022

Comparison Of Volumetric Changes At Implant Connector Among Three Different Types Of Abutment After Cyclic Loading, Piyawan Jirayusakamol

Chulalongkorn University Theses and Dissertations (Chula ETD)

The aim of this study was to compare the volumetric change of dental implant among three different types of abutments after cyclic loading.Thirty dental implants (4.1x10 mm., Straumann®) were used .All of them were inserted in acrylic resin block with usual surgical protocol to gain primary stability and be able to retrieve for volumetric measurement later. Ten of each dental implant connected with Titanium abutment (Group1: Variobase abutment Straumann®), Gold abutment (Group2: UCLA abutment Straumann®) and Zirconia abutment (Group 3: Care abutment Straumann®) consecutively. Then all specimen was submitted to cyclic loading (1x106 cycles, axial load, 100N, 15 Hz) at …

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Association Among Anterior Maxillary Dental Arch Form, Alveolar Bone Thickness And Sagittal Root Position Of Maxillary Central Incisor : A Cone Beam Computed Tomography Analysis, Suttikiat Somvasoontra Jan 2022

Association Among Anterior Maxillary Dental Arch Form, Alveolar Bone Thickness And Sagittal Root Position Of Maxillary Central Incisor : A Cone Beam Computed Tomography Analysis, Suttikiat Somvasoontra

Chulalongkorn University Theses and Dissertations (Chula ETD)

Purpose: This study evaluated the association among the dental arch form, age-sex groups, and sagittal root position regarding alveolar bone thickness in the maxillary central incisor using cone-beam computed tomography (CBCT) images. Materials and Methods: CBCT images of 280 patients were categorized based on the dental arch form and age-sex groups. Five hundred and sixty sagittal CBCT images of the maxillary central incisors were examined to measure the labial and palatal bone thickness at the root apex level, at the mid-root level and 3 mm apically from cemento-enamel junction, with SRP classification. Chi-square, Kruskal-Wallis test, and multiple linear regression were …

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Development Of High Protein Beverage From Hydrolyzed Egg White, Nuntorn Charoensak Jan 2022

Development Of High Protein Beverage From Hydrolyzed Egg White, Nuntorn Charoensak

Chulalongkorn University Theses and Dissertations (Chula ETD)

The primary objective of this study was to examine the impact of enzymatic treatment on pasteurized egg white protein (EWP) and assess its influence on various physicochemical properties and antioxidant activity. Our findings revealed that the addition of SDAY10 enzymes led to a significant increase in lightness (L*), redness (a*), and yellowness (b*) parameters. Furthermore, higher concentrations of the enzyme resulted in a considerable reduction in pH, viscosity, and volume mean diameter (D4,3) of EWP protein compared to the control group (P < 0.05). Additionally, the application of SDAY10 enzyme (0.1-0.3% w/v) for EWP hydrolysis exhibited a noteworthy enhancement in antioxidant activity (measured by DPPH, ABTS, and FRAP assays) compared to lower enzyme concentrations. Notably, the 0.3% concentration of SDAY10 exhibited the highest release of amino acids during in vitro digestion and received the highest sensory evaluation score. Consequently, employing SDAY10 enzymes at a concentration of 0.3% w/v for EWP hydrolysis demonstrates significant potential for improving the physical properties of EWP and enhancing antioxidant activity. However, it is imperative to investigate the sensory evaluation with regards to the bitterness of the product developed using such enzymes.

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Comparison Of Aroma Active Compounds In Fresh Thai Holy Basil Leaves From 2 Varieties, Thanatcha Vichienkalayarat Jan 2022

Comparison Of Aroma Active Compounds In Fresh Thai Holy Basil Leaves From 2 Varieties, Thanatcha Vichienkalayarat

Chulalongkorn University Theses and Dissertations (Chula ETD)

Holy Basil is an herb with a high consumption in Thailand domestically and internationally due to its unique odor. A study on the aroma active profile of holy basil would allow for better quality control and food product development. The goal of this study is to identify and compare aroma active compounds in fresh Thai holy basil leaves from 2 varieties (Ocimum tenuiflorum var. Rama and Ocimum tenuiflorum var. Shyama) using sensomics approach. First, olfactory profiling was performed by trained panelists to characterize odor attributes and their intensity. Second, volatile compounds were isolated by solvent extraction, and non-volatile constituents were …

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Study Of Saliva Transcriptome And Proteome In Thai Patients With Dental Fluorosis, Patcharaporn Gavila Jan 2022

Study Of Saliva Transcriptome And Proteome In Thai Patients With Dental Fluorosis, Patcharaporn Gavila

Chulalongkorn University Theses and Dissertations (Chula ETD)

The purpose of this study was to examine the expression profiles of RNA and protein in Thai individuals with dental fluorosis and compare them with those without fluorosis. Additionally, the study aimed to establish a correlation between the severity of dental fluorosis, urinary fluoride levels, and water fluoride levels. Methods: Schoolchildren in areas endemic for fluoride in Lamphun and Ratchaburi provinces of Thailand were screened for dental fluorosis severity and then enrolled in the study. Fluoride concentration in 24-hour urine and drinking water samples was measured using an ion-selective fluoride electrode. Saliva samples were collected in sterile tubes and stored …

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Oral Health Service Of Older Adults In Long-Term Care Facilities, Puntawee Barameepipat Jan 2022

Oral Health Service Of Older Adults In Long-Term Care Facilities, Puntawee Barameepipat

Chulalongkorn University Theses and Dissertations (Chula ETD)

To assess oral health service in long-term care facilities in Bangkok Methods: A cross-sectional study was conducted in 50 licensed long-term care facilities in Bangkok. Informed consent was obtained from all participants before conducting phone interviews and administering the questionnaire. The questionnaire covered various aspects, including demographics, health services, and oral health services provided within the long-term care facilities. Results: The study revealed variations in terms of operational years, service capacity, service expense per month, and provision of health services, including oral health services. It was found that the differences in service expenses impacted the provision of denture care for …

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Analysis Of Fatty Acid Methyl Esters By Two-Dimensional Gas Chromatography Using Cryogen-Free Modulator, Adrian Jose Sacan Jan 2022

Analysis Of Fatty Acid Methyl Esters By Two-Dimensional Gas Chromatography Using Cryogen-Free Modulator, Adrian Jose Sacan

Chulalongkorn University Theses and Dissertations (Chula ETD)

A simple and environmentally friendly method in two-dimensional gas chromatography coupled with mass spectrometry (GC-MS) and flame ionization detector has been developed for the analysis of fatty acids in commercial milk products. This applies splitter-based non-cryogenic artificial trapping (SNAT) modulator with unique feature imitating the cryogenic modulation process. The method involves chemical derivatization into fatty acid methyl esters (FAME) with methanolic potassium hydroxide, liquid-liquid phase extraction using hexane, and determination of the FAME composition. The GC×GC approach revealed improved separation of FAME using SNAT modulator with better separated peaks, a ten-fold higher total peak capacity and improved compound identification, compared …

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The Potential Risk And Occupational Exposure Of Pesticides Among Rice Farmers In Delta Ayeyarwady Division, Myanmar, Moe Thu Khin Jan 2022

The Potential Risk And Occupational Exposure Of Pesticides Among Rice Farmers In Delta Ayeyarwady Division, Myanmar, Moe Thu Khin

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study aims to assess the potential risk and occupational exposure of pesticides among rice farmers in the Delta Ayeyarwady Region, Myanmar. A cross-sectional study was carried out with 454 rice farmers from March-April 2022. Data collection was done through face-to-face interviews used with a semi-structured questionnaire. The study showed that the mean age of farmers was 44.36 years old while the range was 16 and 74 years old. Rice farmers' average weight (± standard deviation) was 56.86 (± 7.30) kg. In this study, over two-thirds of the rice farmers (77 %) had a moderate level of knowledge regarding environmental …

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Forecasting Cane Sugar Production Under Climate Change And Human-Ecotoxicological Impact, Arisara Tachabunya Jan 2022

Forecasting Cane Sugar Production Under Climate Change And Human-Ecotoxicological Impact, Arisara Tachabunya

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study forecasted sugar cane yield and cane sugar production using stepwise multiple linear regression (MLR) and autoregressive integrated moving average (ARIMA). Then, impacts on human health and ecosystems at the endpoint level were evaluated using openLCA software version 1.10.3 and the ReCiPe 2016 method. The functional units were the production of 1 kg raw sugar, 1 kg granulated sugar, and 1 kg refined sugar at Tamaka Sugar Industry Co., Ltd., Kanchanaburi province, Thailand. The result revealed that relative humidity at the Thong Pha Phum meteorological station, maximum temperature at the Kanchanaburi meteorological station, and oceanic Niño Index (ONI) were …

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Influence Of Tidal Current On Microplastic Dynamics In Chao Phraya River Estuarine Ecosystem, Jiradet Tang-Siri Jan 2022

Influence Of Tidal Current On Microplastic Dynamics In Chao Phraya River Estuarine Ecosystem, Jiradet Tang-Siri

Chulalongkorn University Theses and Dissertations (Chula ETD)

Microplastics (MPs) can be found almost everywhere in marine ecosystems. That is one of the issues of concern around the world, including in Thailand. Estuary ecosystems are also among the most disturbed. By the estuary ecosystem affected by both rivers and oceans, such as the mouth of the Chao Phraya River in Thailand. Due to the change in tide, it is necessary to study the effects of tidal currents on the depth of MPs. Water samples were collected at approximately 60 water levels in 24 hours. Samples and three water quality indicators were collected at Pak Nam Chao Phraya. The …

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Wastewater-Based Epidemiology And Quantitative Microbial Risk Assessment Associated With Wastewater Contact Of Norovirus In Bangkok, Thailand, Nonnarit Sriporatana Jan 2022

Wastewater-Based Epidemiology And Quantitative Microbial Risk Assessment Associated With Wastewater Contact Of Norovirus In Bangkok, Thailand, Nonnarit Sriporatana

Chulalongkorn University Theses and Dissertations (Chula ETD)

Norovirus is one of the leading causes of acute gastroenteritis worldwide. Wastewater surveillance offer significant benefits such as enhancing our understanding of the disease occurrence in the population, evaluating the effectiveness of pathogen reduction in the treatment process, and tracking the spread of pathogens in the environment which pose a health risk to humans. Hence, wastewater surveillance is crucial. In this study, the influent and effluent samples were collected bi-monthly from March 2020 to March 2021 from three distinct wastewater treatment plants in Bangkok. Wastewater samples were concentrated and subjected to quantitative polymerase chain reaction (qPCR) to assess norovirus concentrations. …

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