Digital Commons Network^™

The Prediction Of Pm2.5 Dispersion In Bangkok (Pathumwan District)Using Cfd Modeling, Punyisa Chaisri

Chulalongkorn University Theses and Dissertations (Chula ETD)

City configuration, meteorological conditions and emission source are the important factors affecting the concentration and dispersion of pollutants within urban street canyon. The dispersion of PM2.5 in Pathumwan district, Bangkok which has a characteristics of street canyon was predicted using a Computational Fluid Dynamics (CFD) model. Flow and dispersion of PM2.5 were analyzed using standard k-ε turbulence model. The concentrations of PM2.5 were investigated under different conditions to demonstrate the effect of city configuration in study area, meteorological characteristics, and lockdown due to COVID-19 on PM2.5 concentration. The numerical model was validated with the measured data from the air quality …

Mesoporous Carbon/Silica Nanocomposites With Acid And Base Properties For Glucose Conversion Into Value Added Chemicals, Satit Yousatit

Chulalongkorn University Theses and Dissertations (Chula ETD)

The purpose of this study is to prepare mesoporous carbon/silica (MCS) nanocomposites using natural rubber (NR) as a renewable carbon source. A series of mesoporous nanocomposites based on NR and hexagonal mesoporous silica (HMS), prepared via an in situ sol-gel process, were used as precursors, which were then converted into the MCS materials by carbonization. The sulfonic acid-functionalized mesoporous carbon/silica (MCS-SO3H) was prepared by direct sulfonation with H2SO4 solution. The silica surface of MCS-SO3H were then grafted by 3-aminopropyltrimethoxysilane to produce the acid–base catalysts (MCS-SO3H-NH2) and used as the solid catalysts in glucose conversion. The MCS nanocomposites exhibited enhanced structural, …

Development Of Retention Index Based Simulation For Validation Of Compound Identification In Gc×Gc, Palathip Kakanopas

Chulalongkorn University Theses and Dissertations (Chula ETD)

Comprehensive two-dimensional gas chromatography (GC×GC) is a high-performance technique for separation, identification and quantification of volatiles and semi-volatiles in complex multi-component samples such as biomolecular molecules, essential oil, foods, and petroleum. One of the most popular detectors used for peak identification with GC×GC is mass spectrometer (MS) allowing identification of separated peaks based on comparison with mass spectral library. However, only MS library comparison shows low confidence in compound identifications due to the fact that compounds with similar structures (especially for isomers) often have similar mass spectra. Apart from sample preparation, a great challenge is to effectively select types of …

Effect Of Electric Field On Molecular And Electronic Structures Of Graphene With 4n-Divacancy Defect And Application On Hydrogen Gas Storage, Thanawit Kuamit

Chulalongkorn University Theses and Dissertations (Chula ETD)

The effect of external electric fields (EEFs) on geometries and electronic properties of graphene quantum dots (GQDs) and m-4N-divacancy defect GQDs (m-4N-GQDs) was studied using density functional theory (DFT) method with M06-2x functional and 6-31g (d) basis set. An external electric field with strength ranging from -0.035 to 0.035 atomic units (a.u.) was applied normal to the molecular plane. Three different sizes, i.e., C24H12, C54H18, and C96H24, were investigated. The metal doping in m-4N-GQDs consists of Ca, Ca2+, Cr, Cr2+, Fe, and Fe2+. Our results revealed that GQDs and m-4N-GQDs are curved under EEFs in the direction opposite to the …

Impact Of Early Childhood Caries On Oral Health-Related Quality Of Life Among 5-Year-Old Children In Mandalay, Myanmar, Saw Nay Min

Chulalongkorn University Theses and Dissertations (Chula ETD)

Purpose: The study aimed to develop the cross-cultural adaptation and psychometric properties of the Myanmar Version of SOHO-5 and assess the impact of ECC on oral health quality of life among 5-year-old children in Mandalay using the Myanmar version of the SOHO-5 questionnaire. Materials and methods: The Myanmar SOHO-5 version was conducted with the forward-backward translation method and investigated the content validity, internal consistency, test-retest reliability, construct validity, and discriminant validity on 5-year-old children and their parents in phase I. A cross-sectional study was conducted using a self-administered questionnaire to investigate the impact of ECC and relative factors on the …

Deployment Of Rfid, Gps And Iot Technology For Medical Specimen Logistic System, Mya Myet Thwe Chit

Chulalongkorn University Theses and Dissertations (Chula ETD)

This paper aims to implement a specimen logistic system using RFID technology combined with modern IoT technology in Chulalongkorn hospital. The specimen is a sample collected from the human body. Samples can be urine, saliva, sputum, feces, semen, and other bodily fluids and tissues. Samples are usually collected from the patient and stored in a test tube. Then test tubes are delivered to the corresponding laboratory for examination. Normally, barcodes are tagged over the test tubes for the purpose of recording patient information. In this work, RFID is deployed on the test tube instead for patient data logging. This solution …

Estudio De Las Barreras Lingüísticas Y Culturales De Los Estudiantes De Intercambio Tailandeses En México Y Elaboración De Materiales Audiovisuales Preparatorios, Atapon Krajangjai

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research consists of a triple objective: 1) to study the language and cultural difficulties experienced by Thai exchange students in Mexico, 2) to analyze the causes and effects of such difficulties towards the adaptation of Thai students in Mexico, and 3) to elaborate a proposal of preparatory audiovisual materials that help these students to overcome both language and cultural barriers in Mexico. The research methodology consists of the data collection from the questionnaire taken by a sample group of 84 Thai AFS exchange students in Mexico during the academic year from 2009 to 2019, and the interviews conducted with …

Analysis Of Protein-Protein Interaction Network From Leukocyte Transcriptomic Profiles In Severe Covid -19 Patients, Pakorn Sagulkoo

Chulalongkorn University Theses and Dissertations (Chula ETD)

Coronavirus disease 2019 (COVID-19) still provides global public health issues although several vaccines and antiviral agents have been developed. Some patients experience severe conditions needed medical intensive care, and some are dead due to the failure of treatments. Therefore, identifying the key genes and underlying molecular mechanisms is necessary to discover precisely targeted drugs. Analysis of protein-protein interaction (PPI) networks provides invaluable information to find disease mechanisms and effective alternative drugs. Hence, PPI network analysis based on leukocyte transcriptomic profiles of severe COVID-19 collected from Gene Expression Omnibus (GEO) DataSets was proposed for this study. A network diffusion method called …

Neuroprotective And Neurotherapeuticeffects Of Dihydrotestosterone,17Β-Estradiol, And Pueraria Mirifica Extract On Cognitive Impairment In Androgen Deficient Rats, Taratorn Fainanta

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study aims to understand the mechanism of action of androgen deficiency, which usually occurs in elderly men, and the neuroprotective and neurotherapeutic effects of dihydrotestosterone (DHT), 17β-estradiol (E2) and Pueraria mirifica extract (PME) on cognitive impairment in male rats. Four series of experiments were conducted. Experiment I was to understand the mechanism of action of androgen deficiency on cognitive impairment. Rats at the age of 4 months old were orchidectomized (ODX) or sham-operated (SH), kept for 3 days, 2, 4, 6, and 8 months (M0, M2, M4, M6 and M8, respectively), determined spatial learning behavior and memory capacity, and …

Production And Characterization Of Mannanase From Aureobasidium Sp. For Mannooligosaccharide Preparation From Spent Coffee Ground, Syahriar Nur Maulana Malik Ibrahim

Chulalongkorn University Theses and Dissertations (Chula ETD)

The aims of this study are to produce and characterize mannanase from the selected Thai Aureobasidium strain and use the enzyme for hydrolysis of spent coffee ground extract (SCGE) to prepare mannooligosaccharide (MOs). The optimum condition for SCGE extraction by hot water was 1:30 solid to liquid ratio with 60 min incubation time at 121°C 15 lbs per in2. The maximum yield was 9.5 g/100 g substrate. The second dominant composition of SCGE was hemicellulose at 28 %. Aureobasidium pullulans NRRL 58524 was selected as the best mannanase producer with 8.07 U/mL. The mannanase production medium was optimized by using …

The Supervisory And Regulatory Dilemma On Equity-Based Crowdfunding In Taiwan, Chin-Wei Chang

Chulalongkorn University Theses and Dissertations (Chula ETD)

Equity-based crowdfunding is an important portal for raising fund in Taiwan because the traditional financing sources are unable to meet the capital needs of those who would be able to raise fund through Equity-based crowdfunding. However, Information asymmetry has existed between investors and fundraisers in equity-based crowdfunding. Because fundraisers own and operate the business, they have all information, but investors do not. The GISA regulation can eliminate information asymmetry by imposing disclosure duties on fundraisers. This thesis tries to highlight the necessity for The GISA regulation to reduce information asymmetry. By comparing the GISA with laws and regulations of the …

Depolymerization Of Kraft Lignin To Phenolic Compounds By Electrochemical Advanced Oxidation In Microreactor, Chawakorn Rittirong

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research focuses on the depolymerization of kraft lignin to phenolic compounds that are valuable and useful in various industries. Depolymerization is performed using an electrochemical advanced oxidation process with the hydroxyl radicals. In this process, microreactors are used. It consists of a graphite anode and a stainless steel cathode. The results of the variables studied were current density (3.7 and 5.55 A/m2), residence time (100-400 s), base pH (9), the base difference (sodium hydroxide and potassium hydroxide). The experiment found that the major product is octadecamide and the minor product propyl guaiacol is increased when the current increases. On …

Altering Cardiopulmonary Resuscitation (Cpr) Education For Allied Health Care Providers Based On Self-Reported Experiences With Recertification, Kassiann Deen Landin

Health Nutrition and Exercise Science

Health care providers (nurses, athletic trainers, and emergency medical services [EMS] personnel) are expected to perform high-quality cardiopulmonary resuscitation (CPR) regardless of their confidence. Also, regardless the design of CPR recertification courses, it is expected that health care providers perform high-quality CPR. The first goal of the study pertained to self-efficacy. This research investigated health care professionals reports of self-efficacy of CPR performance with the current CPR guidelines for a specific amount of time as well as over athletic equipment. Secondly, this research explored differences in recertification expectations and educational approaches between professions. Ninety-nine health care professionals (36 nurses, 36 …

An Analysis Of Muscle Activity During Load Carriage, Acft Scores, And Back Pain In Army Rotc Cadets, Jennifer Ann Longo

Health Nutrition and Exercise Science

Context: Low back pain (LBP) is a leading musculoskeletal complaint among the military population. Load carriage tasks are a frequently reported mechanism of injury for low back pain (LBP) in the Army. Furthermore, researchers have demonstrated a clear association between physical fitness and injury incidence. Objectives: 1) to analyze changes in muscle activity during load carriage and how LBP relates to changes in muscle activation; and 2) to analyze a possible relationship between performance on the Army Combat Fitness Test (ACFT) and LBP, muscle activity, and kinesiophobia in Army Reserve Officer Training Corps (ROTC) cadets. Methods: 30 Army ROTC cadets …

Impacts Of Microbial Seed Inoculants On Growth Of Field Pea (Pisum Sativum L.), And Implications For Plant-Insect Interactions, Benjamin Patrick Glogoza

Entomology

Soil microbes that associate with plant roots can benefit plants by increasing the supply or availability of nutrients to increase the plant’s resilience to abiotic and biotic stress, crop germination rates, root and shoot growth, flower production, and yield. We evaluated the impact of five commercially available treatments: 1) B5, Bacillus bacteria, 2) GP, Trichoderma fungi, 3) N2, Paenibacillus nitrogen-fixing bacteria, 4) combination of B5+GP+N2, and 5) water control, and soil-dwelling Collembola on growth and biomass distribution of the specialty crop field pea in a greenhouse setting. We assessed plant growth (e.g., height, biomass of shoots and roots) and results …

Developing Maritime Digital Competencies, Rory Hopcraft

School of Engineering, Computing and Mathematics

No abstract provided.

Wave Modulation Of Flows On Open And Closed Reefs, M Lindhart, Js Rogers, Sa Maticka, Cb Woodson, Sg Monismith

School of Biological and Marine Sciences

Using observations, numerical models, and theory, we explore a framework to classify reefs as open or closed based on their dynamics. While the concepts of open and closed reefs are used widely in studies of coral reef hydrodynamics and are generally based on geometry, there is no consensus on what qualifies as open and closed. With observations from Ofu, American Samoa, we show that the reef flat exhibits two different dynamical regimes depending on tidal and wave forcing. Flow over this reef flat resembles a classic one‐dimensional barrier reef flow during low tide, where wave setup creates a cross‐reef pressure …

Evaluation Of Extraction Methods And Groat Type With Effects On Quality Analysis Of Oat Beverage, Brandon Robert Olson

Cereal Science

The recent uptick in consumption of plant-based beverages has forced companies to modify production methods to further optimize the process. The objective of this study was to evaluate how groat type, water to grain ratio, and extraction method affect the quality and composition of oat beverage. Wet milling and the use of an amylase treatment produced significantly (p<0.05) higher values of degree Brix, solids, and total starch within the beverage base. Stabilized groats produced the highest value of total starch of 61.97%. Microbial analysis revealed that amylase treated products had a much lower colony forming units per gram (CFU/g), when compared to dry and wet milling. To produce an oat beverage with ideal rheological and composition values, the beverage must be derived from heat treated groats, a grain to water ratio of 1:4, and must undergo an α-amylase treatment.

Corrosion Investigation Of Structural Transition Joints Through Scanning Electrochemical Microscopy And The Characterization Of High-Temperature Coatings At Different Temperatures, Luke Peter Wiering

Coatings and Polymeric Materials

Scanning electrochemical microscopy is a method that incorporates an ultramicroelectrode capable of facilitating electrochemical reactions paired with an XYZ positioning system capable of micron-level movements. This study investigates the corrosion behavior of structural transition joint clad material that contains steel, pure aluminum, and an aluminum alloy blast welded into a single joint. This study will characterize the corrosion response of the structural transition joint and identify the galvanic activity measured between its layers. High-temperature coatings in this study are designed to be used effectively up to 1400°F. In this study, we characterized several commercial high-temperature coatings exposed to different levels …

Phytic Acid Enriched Biobased Membranes For Lead Ion Removal From Water, Mayur Indal Ukey

Coatings and Polymeric Materials

Pollution by heavy metals, such as lead (Pb), in bodies of water is a serious problem today that poses great risk to human health and the environment. In this study, cellulose-acetate (CA) based membranes were synthesized by immersion precipitation process, and commercially available CA membranes were modified by a layering method. Phytic acid (PA), a phosphorus rich compound known for its chelating properties, was doped into the membrane films to improve their efficiency in removing Pb (II) ions from water. As formulation additives, cellulose nanocrystals (CNCs), amine-functionalized cellulose nanofibers (CNFs) and chitosan were used. Mechanical properties, and filtration efficiency of …

Advancing Plant Protein-Based Proteoposite Films Targeted For Food Packaging Applications. A Combined Computational And Experimental Approach, Kristen Lorraine Patnode

Coatings and Polymeric Materials

Demand for polymeric, plastic materials continues to grow each year. However, the limited supply of fossil-fuels and negative environmental impact caused by petrochemical products have led to an increased demand for bio-based plastic alternatives. While there is great interest in developing plant-based alternatives to plastic packaging products, industrial applications of such materials are limited and development of said products is time, cost, and resource consuming. For this reason, advanced, marketable plant-based bioplastics must be developed more efficiently. To achieve such a goal, this thesis outlines a combined computational and experimental approach which results in novel plant proteins-based (proteoposite) films, that …

Using Conditional And Unconditional Process Approaches To Determine The Effectiveness And Comprehensiveness Of Instructional Risk And Crisis Communication Messages, Kimberly Beauchamp

Communication

Many individuals willingly or unknowingly consume food products that have been implicated in recall announcements. Exposure to potentially contaminated food products puts people at risk for contracting foodborne disease. Given the serious health complications associated with foodborne disease, a new message-design approach was needed that compels and empowers at-risk individuals to take appropriate life-saving actions when food-related, public health crises become imminent. The IDEA protocol was put forth to improve how we instruct and motivate at-risk audiences to self-protect against foodborne disease during food contamination events (T. Sellnow & D. Sellnow, 2013). IDEA-modeled messages, relative to alternative messages, are predicted …

Post-Fire Damage And Corrosion In Structural Steels: Characterization And Prevention, Hizb Ullah Sajid

Civil and Environmental Engineering

Steel structures frequently experience extreme service conditions such as fire accidents, corrosion, etc., resulting in significant deterioration, reduced service life, and increased maintenance cost. Almost 0.5 million structural fire accidents are reported annually in the U.S., inflicting a considerable toll on infrastructure. Similarly, corrosion-induced deterioration is the leading cause of premature failure in infrastructure and costs $22.6 billion in infrastructure maintenance annually. The bridge infrastructure vulnerability to these extreme service conditions is compounded by the aging bridge inventory (42% of the 617,000 bridges in the U.S. are 50 years or older). To improve the resilience and the “C-” infrastructure grade, …

Exploring Patterns Of Ongoing Thought Under Naturalistic And Conventional Task-Based Conditions, Delali Konu, Brontë Mckeown, Adam Turnbull, Ping Ho N Siu, Theodoros Karapanagiotidis, Tamara Vanderwal, Cade Mccall, Steven P. Tipper, Elizabeth Jefferies, Jonathan Smallwood

More Faculty of Health Research

Previous research suggests that patterns of ongoing thought are heterogeneous, varying across situations and individuals. The current study investigated the influence of multiple tasks and affective style on ongoing patterns of thought. We used 9 different tasks and measured ongoing thought using multidimensional experience sampling. A Principal Component Analysis of the experience sampling data revealed four patterns of ongoing thought: episodic social cognition, unpleasant intrusive, concentration and self focus. Linear Mixed Modelling was used to conduct a series of exploratory analyses aimed at examining contextual distributions of these thought patterns. We found that different task contexts reliably evoke different thought …

Addressing Challenges In Data Privacy And Security: Various Approaches To Secure Data, Sayantica Pattanayak

Computer Science

Emerging neural networks based machine learning techniques such as deep learning and its variants have shown tremendous potential in many application domains. However, the neural network models raise serious privacy concerns due to the risk of leakage of highly privacy-sensitive data. In this dissertation, we propose various techniques to hide the sensitive information and also evaluate the performance and efficacy of our proposed models. In our first research work we propose a model, which can both encrypt and decrypt a ciphertext. Our model is based on symmetric key encryption and back propagation neural network. Our model takes the decimal values …

Building Plant 3d Genome Computing Resources, Chanaka Sampath Cooray Bulathsinghalage

Computer Science

Chromatin interactions play increasingly important roles in three-dimensional genome organization and long-range gene regulation. Analyzing the three-dimensional structure of the plants is currently a growing field and we noticed that there is lack of computing resources on chromatin interactions for the plants. So, we are introducing a database of statistically significant chromatin interactions processed using Hi-C experimental approach. The users can search in the database using a set of genes or regions for a selected plant organism through a web browser and it lists down all the statistically significant chromatin interactions involved those genes or regions with the confidence scores, …

Structural Characterization And In Vitro Antiproliferative Activity Of Non-Specific Lipid Transfer Protein 1 (Nsltp1) From Fennel (Foeniculum Vulgare) Seeds, Mekdes Megeressa

Pharmaceutical Sciences (PhD) Dissertations

Non-specific lipid transfer proteins (nsLTPs) are cationic proteins involved in intracellular lipid shuttling, in growth and reproduction, as well as in defense against pathogenic microbes. Even though the primary and spatial structures of some nsLTPs from different plants indicate their similar features, they exhibit distinct lipid-binding specificities signifying their various biological roles that dictate further structural study. The present study determined the complete amino acid sequence, in silico 3D structure modeling, and in vitro antiproliferative activity of nsLTP1 from fennel (Foeniculum vulgare) seeds.

Fennel is a member of the family Umbelliferae (Apiaceae) native to southern Europe and the …

Amphiphilic Cell-Penetrating Peptides Containing Natural And Unnatural Amino Acids As Drug Delivery Tools And Antimicrobial Agents, David Salehi

Pharmaceutical Sciences (MS) Theses

Cell-penetrating peptides containing arginine as positively charged residues and tryptophan or diphenylalanine as hydrophobic residues were synthesized. The synthesis was accomplished through the Fmoc solid-phase peptide synthesis in the presence of HBTU and DIPEA. The side-chain protected linear peptides were cleaved from the resin and cyclized in the presence of DIC and HOAt in the solution phase overnight. MALDI-TOF mass spectrometry was used to characterize the peptides.

The cytotoxicity of the synthesized peptides was determined in CCRF-CEM (human, lymphoblast peripheral blood), and HEK-293 (human, embryonic epithelial kidney healthy) cells using the MTS assay. A concentration of 10 µM was found …

Comparison Of Global And Local Particle Swarm Optimization, Nazrin Ferdousi

Computer Science

Particle swarm optimization is a computational algorithm used to optimize a solution through sequential processing of particles using a specified estimation of quality. The algorithm is inspired by biological systems such as bird and insect swarms. This paper focuses on the comparison between Local PSO and Global PSO. We have utilized eight functions to provide benchmarks to compare the optimizations provided by the two optimization strategies. This resulted in findings that indicate that global optimizations tend to be more effective than local optimizations when comparing final costs. Our research indicates that an automated approach to particle swarm optimization will benefit …

Analyzing Three Different Tuning Strategies For Random Forest Hyperparameters For Fraud Detection, Kulwinder Kaur Sarao

Computer Science

Technology is advancing rapidly, and more tasks are becoming online than ever. Along with the benefits comes the disadvantages of this great advancement. While online services relieve from the struggle of in person activities, it also puts you on the risk of getting deceived by the fraudsters. This paper aims to detect the fraudulent transactions made online from a bank using a synthetically produced dataset. A random forest model has been trained to predict the fraudulent transactions. To achieve the best performance, the hyperparameters of the model have been tuned using three different tuning methods. As it turns out, grid …