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2021

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Colorimetric And Fluorescent Detection Of Nucleic Acid By Styryl Dyes, Kotchakorn Supabowornsathit Jan 2021

Colorimetric And Fluorescent Detection Of Nucleic Acid By Styryl Dyes, Kotchakorn Supabowornsathit

Chulalongkorn University Theses and Dissertations (Chula ETD)

Nucleic acid staining dyes are essential tools for the analysis and visualizing of DNA/RNA in vitro and in cellular applications. Although there are several commercially available dyes developed during the past few decades, the selection is still relatively limited, and they are often very costly and associated with undesirable characteristics such as toxicity. Consequently, the discovery of nontoxic, readily available dyes, with desirable and controllable optical characteristics remains important. Styryl dyes have recently gained popularity as potential biological staining agents with many desirable properties including a straightforward synthesis procedure, excellent photostability, tunable optical properties, and high responsiveness towards nucleic acid …

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Synthesis Of Quantum Dot-Based Fluorescent Sensors For Detection Of Anionic Metabolites And Copper (Ii) Ion, Nattakarn Phromsiri Jan 2021

Synthesis Of Quantum Dot-Based Fluorescent Sensors For Detection Of Anionic Metabolites And Copper (Ii) Ion, Nattakarn Phromsiri

Chulalongkorn University Theses and Dissertations (Chula ETD)

Oxalate, citrate, and urate are the anionic metabolites that are the products of the metabolism pathway of living organisms. The high level of these anionic metabolites is related to the diseases. For example, the excess amount of oxalate ions in urine indicates the risk of kidney stones, while the level of citrate can suggest the risk of cancer. The level of urate in urine is related to the risk of gout. The detection of these anionic metabolites is significant and still remains a challenge. Thus, this work aims to develop the more sensitive and selective fluorescence sensing of oxalate in …

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Pna-Immobilized Paper For Detection Of Pcr Amplicons, Nuttapon Jirakittiwut Jan 2021

Pna-Immobilized Paper For Detection Of Pcr Amplicons, Nuttapon Jirakittiwut

Chulalongkorn University Theses and Dissertations (Chula ETD)

DNA detection is very important in diverse fields leading to a continuous increase in the research and development of various DNA sensors. This study focuses on the development of a paper-based DNA sensor by using pyrrolidinyl PNA as a recognition probe. The PNA-immobilized DNA sensor was designed to contain several PNA probes in the same device as a self-check system to increase the accuracy and facilitate the data collection and interpretation. The PNA-immobilized paper was then utilized for the detection of the DNA target, followed by the visualization of the captured target DNA via an enzyme-catalyzed colorimetric reaction. In this …

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Thin-Layer Chromatography For Determination Of Phenolic Compound Profile And Antioxidant Activity Of Thai Honey, Pattraporn Chobpradit Jan 2021

Thin-Layer Chromatography For Determination Of Phenolic Compound Profile And Antioxidant Activity Of Thai Honey, Pattraporn Chobpradit

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this study, a small-scale method using thin-layer chromatography (TLC) was developed to determine profile and antioxidant activity value of Thai honey samples obtained from different flora sources. Prior to TLC analysis, the samples were prepared by solvent extraction with dichloromethane. Using 2, 2-diphenyl-1-picrylhydrazy radical (DPPH•) reacted with the samples extract prior to TLC spot and color detection with imageJ, half-maximal inhibitory concentration (IC50) values of seven honey samples was obtained in a range of 9 to 22 mg/mL in comparison with IC50 values of 0.13 mg/mL for L-ascorbic acid (LA), along with limit of detection (LOD) and limit of …

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Theoretical Study Of Ethylene Polymerization By Phenoxy-Imine Catalyst, Pavee Apilardmongkol Jan 2021

Theoretical Study Of Ethylene Polymerization By Phenoxy-Imine Catalyst, Pavee Apilardmongkol

Chulalongkorn University Theses and Dissertations (Chula ETD)

Reaction mechanisms of ethylene polymerization catalyzed by the phenoxy-imine (FI) and the nickel phenoxyphosphine polyethylene glycol (Ni-PEG) with alkali metals were explored using DFT calculations. For FI catalysts, the effect of group IVB transition metals substitutions was investigated. The trend of calculated activation energies (Ea) at the rate-determining step is Zr < Hf < Ti and is in good agreement with experiments. The effect of ligands of the Ti-FI-based catalysts when changing the parent nitrogen (O, N) to oxygen (O, O), phosphorus (O, P), and sulfur (O, S) ligands on activity was also monitored. The results indicated that the sulfur (O, S) ligand gives the lowest activation energy. Additionally, the reactivity of Ni-phenoxy-imine (Ni-FI)-based catalysts for polyethylene polymerization was studied. Our calculations suggested that the square planar complex of Ni-FI is more reactive than its C2 symmetric octahedral complex. For Ni-PEG(M) catalysts, the trend for activation energies of four Ni-PEG(M) systems is Li < Na < K < Cs, which corresponds to experimentally observed activities. Moreover, the roles of secondary metals in Ni-PEG catalysts in terms of steric, electronic, and electrostatic effects were elucidated. The DFT results suggested that the active catalyst should have strong cooperative metal-metal/metal-ligand interactions and less positive charge on the secondary metal. Finally, to gain insight into the design of the novel Ni-PEG catalysts with alkali-earth metals, the effect of catalyst structure on experimental activity was investigated. This work provides fundamental understandings of the reaction mechanisms for the FI and Ni-PEG(M) catalysts, which could be used for the design and development of catalysts for ethylene polymerization.

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Discrimination Of Weedy Rice By Using Near-Infrared Spectroscopy Combined With Chemometrics, Sureerat Makmuang Jan 2021

Discrimination Of Weedy Rice By Using Near-Infrared Spectroscopy Combined With Chemometrics, Sureerat Makmuang

Chulalongkorn University Theses and Dissertations (Chula ETD)

Weedy rice is one of the most notorious weeds occurring in rice-growing areas, especially in South-East Asia. Weedy rice especially in form of paddy seed is difficult to manage and separate as they provide common features (morphological resemblance) to cultivated rice. This work presents a modification of self-organizing map (SOMs) for the classification of weedy rice from cultivated rice via in situ direct sample analysis from paddy seed using near-infrared (NIR) spectroscopy and hyperspectral NIR camera. The sample pretreatment was carried out by a cyclone vacuum machine to remove the contaminated particles and other impurities. The physical characteristics and the …

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Lamellar Inorganic Solids And Biochar Nanocomposites For Sorptive Removal Of Metal Ions And Nitrophenol, Sutasinee Sutthiklub Jan 2021

Lamellar Inorganic Solids And Biochar Nanocomposites For Sorptive Removal Of Metal Ions And Nitrophenol, Sutasinee Sutthiklub

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this research, the adsorbents of ternary-component composites were developed to remove various types of toxic chemicals. The selected three components are clay, MgAl-layered double hydroxide (MgAl-LDH) and biochar because they are nontoxic and low cost and also possess high adsorption capacity and high surface area. The composites were synthesized by the combination of post-pyrolysis and co-precipitation methods, and characterized by XRD and SEM-EDS. The result shows that clay and LDH particles distributed and deposited on the biochar matrix, confirming the coexistence of three phases in micrometer and nanometer scales. Ni2+, CrO42- and 4-Nitrophenol were chosen as the representatives of …

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Development Of Colorimetric Paper-Based Analytical Device For Cortisol Detection, Thanathip Kosawatphat Jan 2021

Development Of Colorimetric Paper-Based Analytical Device For Cortisol Detection, Thanathip Kosawatphat

Chulalongkorn University Theses and Dissertations (Chula ETD)

Nowadays, the detection of cortisol can play a key role in understanding stress-related diseases. Several competitive immunoassay formats have been reported for the detection of this small hormone molecule. Lateral flow immunoassay (LFIA) is one of the most widely used platforms that offer its simplicity and rapidity for such analysis. Unlike previous sensors for cortisol sensing that require complicated readers, specialized reagents, or even post-treatment methods to amplify the obtained signal, in this work, we employed a concave test zone constructed on the LFIA device (cLFIA) which can directly enhance the signal response as the flowing sample was substantially concentrated …

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Application Of Oxygen Scavenger In Gel Electromembrane Extraction For Determination Of Nitrite And Nitrate, Thidarat Samkumpim Jan 2021

Application Of Oxygen Scavenger In Gel Electromembrane Extraction For Determination Of Nitrite And Nitrate, Thidarat Samkumpim

Chulalongkorn University Theses and Dissertations (Chula ETD)

Gel electromembrane microextraction (G-EME) have been proven as a promising extraction method due to its effectiveness for extraction and preconcentration of charged analytes and its compliance with the principle of green chemistry. G-EME consists of two phases (donor and acceptor phases), separated by a gel membrane made of agarose. The driving force is the electrical potential applied across the membrane. Despite of all the advantages, the common problem was the oxygen generated in the acceptor solution due to the electrolysis of water that could affect the analysis of easily oxidized analyte species such as nitrite/nitrate species. In this work, application …

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Histone 3 And Histone 4 Acetylation Pattern In Well-Differentiated Thyroid Lesions And Normal Thyroid Tissue With Their Potential In Diagnostic Implication, Nishal Chhetri Jan 2021

Histone 3 And Histone 4 Acetylation Pattern In Well-Differentiated Thyroid Lesions And Normal Thyroid Tissue With Their Potential In Diagnostic Implication, Nishal Chhetri

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study estimated the histone modification (hypoacetylation or hyperacetylation) in thyroid lesions, using immunohistochemistry compared with their normal counterpart. FFPE sections of surgically removed PTC, FA, FTC, and nodular goiter samples were collected from the archives of the Department of Pathology, Faculty of Medicine, Chulalongkorn University from 2016-2018 and stained with anti-acetyl histone 3 antibody (H3K9/K14ac) and anti-acetyl histone 4 antibody (H4K5,8,12 and 16ac). The intensity and proportion of immunostaining of the lesions and their normal thyroid tissue counterparts were automatically scored by Aperio ImageScope software. A total of 147 benign and malignant thyroid lesions cases, including 28 FA, 50 …

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Impact Of Early Childhood Caries On Oral Health-Related Quality Of Life Among 5-Year-Old Children In Mandalay, Myanmar, Saw Nay Min Jan 2021

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 …

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Deployment Of Rfid, Gps And Iot Technology For Medical Specimen Logistic System, Mya Myet Thwe Chit Jan 2021

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 …

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Identification And Counting White Blood Cell Subtypes With Convolutional Neural Network, Singgih Bekti Worsito Jan 2021

Identification And Counting White Blood Cell Subtypes With Convolutional Neural Network, Singgih Bekti Worsito

Chulalongkorn University Theses and Dissertations (Chula ETD)

White blood cell (WBC) has five subtypes namely neutrophil, eosinophil, basophil, lymphocyte, and monocyte which play specific roles in the immune system and against diseases. The object detection model applied to microscopic objects is introduced to assist experts in performing tasks in blood analysis. Unbalanced cell composition of WBC subtypes to be detected is a challenge in building a model in Convolutional Neural Network (CNN). This research aims to build models in recognizing and counting WBC subtypes with neural networks constructed from augmented data enrichment. CNN is demonstrated in this study with the YOLOv5s, YOLOv5l, and YOLOv5x models to detect …

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Environmental Ethics, Survival And Apocalypse: An Analysis Of Margaret Atwood’S Maddaddam Trilogy, Sarawut Kururatphan Jan 2021

Environmental Ethics, Survival And Apocalypse: An Analysis Of Margaret Atwood’S Maddaddam Trilogy, Sarawut Kururatphan

Chulalongkorn University Theses and Dissertations (Chula ETD)

This thesis examines the connection of ethics and survival in the pre- and post-apocalyptic worlds in Margaret Atwood's MaddAddam trilogy: Oryx and Crake (2003), The Year of the Flood (2009), and MaddAddam (2013). It investigates the author’s imaginings of a dystopian society marked by rampant technocratic capitalism and unchecked scientism in Oryx and Crake. Applying Murray Bookchin's social ecology to shed light on the root causes of the apocalypse, it argues that hierarchical ideology and diversiform inequality deeply rooted in society lead to warped ethics, affecting the crisis. This thesis also examines environmental ethics which is embedded in the belief …

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Developing Tanjung Kelayang As A New Bali: An Analysis Of Sustainable Tourism Policy And Implementation, Herdi Andrariladchi Jan 2021

Developing Tanjung Kelayang As A New Bali: An Analysis Of Sustainable Tourism Policy And Implementation, Herdi Andrariladchi

Chulalongkorn University Theses and Dissertations (Chula ETD)

Indonesia has seen the success of Bali as the most prominent tourism destination in the country. Therefore, the initiative to deploy the benefits of tourism development throughout several regions of Indonesia is known as the “10 New Bali’s”. Nevertheless, it is still questionable whether Bali is an example of sustainable tourism or not. In developing the “10 New Bali’s”, the Indonesian government is aiming at increasing the number of tourists rather than at achieving the goal of sustainable tourism destination development. One of the destinations designated under this initiative is Tanjung Kelayang in Belitung Island, and therefore it is selected …

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Challenges Of Urban Forest Park Restoration On Post-Closure Landfill : Perception And Future Engagement From The Local Communities, Intan Pransischa Fitri Jan 2021

Challenges Of Urban Forest Park Restoration On Post-Closure Landfill : Perception And Future Engagement From The Local Communities, Intan Pransischa Fitri

Chulalongkorn University Theses and Dissertations (Chula ETD)

Urban forest park development is considered a promising planning tool in tackling some of the problems associated with urbanisation, such as pollution and urban heat island effects. Individual perceptions are pivotal in the urban forest park development. Their significant factors were aimed to address the community's needs and increase the recognition through the disruptive change of land function and urban living toward urban forest park development. The framework of local community engagement in urban forest park development was proposed. Field observation and questionnaires survey of 168 respondents were selected from five villages located 50 meters-1000 meters radius from the site. …

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Preventing Occupational Respiratory Disease From Exposures In Office Building : Case Study Covid-19, Panupant Phapant Jan 2021

Preventing Occupational Respiratory Disease From Exposures In Office Building : Case Study Covid-19, Panupant Phapant

Chulalongkorn University Theses and Dissertations (Chula ETD)

The COVID‐19 pandemic has affected human life in every possible way, and, alongside this, the need has been felt that office buildings and workplaces must have protective and preventive layers against COVID‐19 transmission so that a smooth transition from ‘work from home’ to work from office’ is possible. The present study reviews international agency regulations, country regulations, updated journal articles, etc., to critically understand lessons learned from COVID‐19 and evaluate the expected changes in sustainability requirements of office buildings and workplaces. The built environment, control environment, and regulatory environment around office buildings and workplaces have been put under test on …

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Developing A System Of Community-Based Agritourism For Sustainable Local Food Systems: A Multi-Case Study Of Rural Livelihood Diversification And Sustainable Urban Consumption In City-Regional Bangkok, Sofia Anna Enrica Cavalleri Jan 2021

Developing A System Of Community-Based Agritourism For Sustainable Local Food Systems: A Multi-Case Study Of Rural Livelihood Diversification And Sustainable Urban Consumption In City-Regional Bangkok, Sofia Anna Enrica Cavalleri

Chulalongkorn University Theses and Dissertations (Chula ETD)

Current food systems fail to directly link rural producers and urban consumers. This research explores and categorizes emerging community-based agritourism practices as strategies to reconnect rural food producers with urban consumers. The main research question of this study is: how can community-based agritourism link rural food producers and urban consumers as a rural livelihood diversification strategy? Mixed methods for data collection were selected to answer this question and analyzed with a deductive and inductive approach. These include the review of secondary grey and academic literature, shadow observation in three rural provinces, content validity index calculation performed by experts (n = …

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Developing A Model For The Integration Of Bajau Traditional Ecological Knowledge In The Management Of Locally Managed Marine Area: A Case Study Of Wakatobi Regency, Indonesia, Wengki Ariando Jan 2021

Developing A Model For The Integration Of Bajau Traditional Ecological Knowledge In The Management Of Locally Managed Marine Area: A Case Study Of Wakatobi Regency, Indonesia, Wengki Ariando

Chulalongkorn University Theses and Dissertations (Chula ETD)

Attaining sustainable resource management encompasses multilevel challenges and interdisciplinary approaches from grassroots efforts to international agreements. In the context of coastal and marine management, the complexities represented by the variety of local entities, regimes, and institutional supports are captured as current challenges in sustainability efforts. Such challenges, unfortunately, persist in the group of customary communities such as those of the Bajau, who live in coastal and marine areas. In an effort to address the aforementioned challenges, this research proposes a model for integrating the Traditional Ecological Knowledge (TEK) of the Bajau into Locally Managed Marine Areas (LMMA) scheme in Wakatobi, …

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Effects Of Configuration And Operating Conditions On Turbidity Removal Of Jet Clarifier, Ploypailin Romphophak Jan 2021

Effects Of Configuration And Operating Conditions On Turbidity Removal Of Jet Clarifier, Ploypailin Romphophak

Chulalongkorn University Theses and Dissertations (Chula ETD)

In water treatment, flocculation creates large and weighty flocs enough to be removed by the downstream processes of sedimentation and filtration. Among the various existing technologies, the jet clarifier is considered as an effective and compact system as it couples flocculation and clarification in a single unit. For the design of jet mixing, much experimental work has been done and many correlations have been proposed. However, these correlations are case specifics, and, to date, there is no comprehensive view for the flocculation aspect. In order to evaluate the performance of the jet clarifier for turbidity removal and understand hydrodynamics to …

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A Comparison Of Implant Stability Between Two Dental Implant Designusing Two Different Stability Measuring Technique, Chanikarn Chaksupa Jan 2021

A Comparison Of Implant Stability Between Two Dental Implant Designusing Two Different Stability Measuring Technique, Chanikarn Chaksupa

Chulalongkorn University Theses and Dissertations (Chula ETD)

Objective To investigate the primary stability of aggressive thread design implant comparing to nonaggressive thread design implant and to evaluate the correlation between ISQ values and IST values. Materials and methods 96 implants were used in this study. 48 BLT Straumann® and 48 BLX Straumann® were used. All implants were digitally planned and placed in 3D printed model using computer assisted guided surgery. The edentulous area at models were packed with randomized pattern of four different kinds of polyurethane blocks to replicate mixed cancellous bone. Postoperative implant stability measurement was performed immediately after implant insertion. Implant stability was measured by …

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The Relative Occlusal Force Of Natural Tooth Adjacent To Distal Extension Implant Support Fixed Prosthesis Using T-Scan Analysis : A Cross Sectional Study, Chin Purintarapiban Jan 2021

The Relative Occlusal Force Of Natural Tooth Adjacent To Distal Extension Implant Support Fixed Prosthesis Using T-Scan Analysis : A Cross Sectional Study, Chin Purintarapiban

Chulalongkorn University Theses and Dissertations (Chula ETD)

Objective: This cross-sectional study aimed to compare the relative occlusal force between implant in the distal end and tooth adjacent to implant in maximum intercuspation. Methodology: Patients with implant restoration replacing teeth in free end space adjacent to natural tooth were recalled. The occlusion is examined as shim stock passes through the occluded tooth in heavy or light bites. The heavy bite or a light bite with shim stock that cannot pull through is HB1 or LB1. If the shim stock can pull through it is considered HB0 or LB0. The implant is classified into 3 groups, HB1LB0, HB1LB1, and …

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A Comparison Of Implant Stability Between Two Implant Systems Using Guided Surgery In Inexperienced Surgeons, Pinmuk Supachaiyakit Jan 2021

A Comparison Of Implant Stability Between Two Implant Systems Using Guided Surgery In Inexperienced Surgeons, Pinmuk Supachaiyakit

Chulalongkorn University Theses and Dissertations (Chula ETD)

Aim: To investigate the implant stability in relation to two different implant designs, a cylindrical shaped single threaded design (CS/ST) and a tapered shaped double threaded design (TS/DT) using RFA over the first 8 weeks. Materials and Methods: 28 implants were randomly allocated into two groups and were placed as single tooth implant in the posterior arch. CBCT scan was used to determine the bone density and the implants were placed with guided surgical template by inexperienced surgeons which were prepared with the same implant planning software. The implant stability was measured using the RFA over the first 8 weeks …

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Clinical Accuracy Between Planned And Placed Posterior Implant Position Of Two Static Implant Planning Software Programs In Inexperienced Operators, Wanwanat Singthong Jan 2021

Clinical Accuracy Between Planned And Placed Posterior Implant Position Of Two Static Implant Planning Software Programs In Inexperienced Operators, Wanwanat Singthong

Chulalongkorn University Theses and Dissertations (Chula ETD)

Objective: This study aimed to evaluate and examine the difference in posterior implant positioning between the planned and placed positions when inexperienced operators used two static implant planning software packages following a fully guided implant surgery protocol in the clinical field. Materials and methods: Twenty-four patients who needed single posterior implant placement were randomly divided into two groups based on the used implant planning software (group 1, coDiagnostiX, n=12; group 2, Implant Studio, n=12). The dataset of the placed implant position, generated from digitizing the implant impression, was superimposed on the planned implant position. The number of horizontal, angular, and …

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Solid-State Modification Of Tapioca Starch Using Non-Thermal Plasma, Natchanon Srangsomjit Jan 2021

Solid-State Modification Of Tapioca Starch Using Non-Thermal Plasma, Natchanon Srangsomjit

Chulalongkorn University Theses and Dissertations (Chula ETD)

The objective of this research was to investigate the physical, chemical, and functional properties of tapioca starch subjected to solid-state modification by using nonthermal dielectric barrier discharge (DBD) plasma treatment using different gases (helium and argon), voltage levels (10 kV and 15 kV), and treatment times (5, 10, and 15 minutes). After treatment, an increase in L* value and a marginal decrease in pH value of all treated samples were noted. Scanning electron micrographs showed dented starch granules after the plasma treatment but showed birefringence. From XRD measurement, all samples showed a characteristic C-type diffraction pattern but a reduction in …

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Analysis Of Ancient Storm Deposits Along Coastal Areas Of Andaman Sea, Thailand And Coastal Areas Of South China Sea, Vietnam, Stapana Kongsen Jan 2021

Analysis Of Ancient Storm Deposits Along Coastal Areas Of Andaman Sea, Thailand And Coastal Areas Of South China Sea, Vietnam, Stapana Kongsen

Chulalongkorn University Theses and Dissertations (Chula ETD)

The frequency of high energy storm and tsunami events is crucial for apprehending the vulnerability of coastal communities. Identifying and dating sedimentary evidence deposited by such high energy events can assist in the planning and installation of suitable protection measurements. The Andaman Sea coast of Thailand is particularly vulnerable to such events as illustrated by the 2004 Indian Ocean Tsunami (2004 IOT) and the South China Sea coast of Vietnam has been experienced from the past severe storm event. Here, the authors study the high energy sediments. The selected area of Andaman Sea coast Thailand is Laem Son National park, …

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The Effectiveness Of Asiaticoside On Osteogenic Differentiation Ability In Aging Human Periodontal Ligament Cells In Vitro, Adisa Suthirathikul Jan 2021

The Effectiveness Of Asiaticoside On Osteogenic Differentiation Ability In Aging Human Periodontal Ligament Cells In Vitro, Adisa Suthirathikul

Chulalongkorn University Theses and Dissertations (Chula ETD)

Retaining teeth is essential for the quality of life of the aging population. However, aging has biological effects in periodontal ligament cells with significant changes in their proliferative rate and regenerative function. Asiaticoside, extracted from Centella asiatica, was found to have potential in osteogenic differentiation and mineralization in human periodontal ligament cells (HPDLCs). The aim of this study is to investigate the effect of asiaticoside on the aging HPDLCs osteogenic differentiation and mineralization. Aging HPDLCs, retrieved from patients age 60 and above, were confirmed aging status using Senescence-Associated ß -Galactosidase assay. The cells were incubated with various concentrations of asiaticoside …

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Utilization Of Rain Tree (Samanea Saman) Residue As Modified Adsorbent To Treat Oil And Grease In Canteen Wastewater, Elga Riesta Puteri Jan 2021

Utilization Of Rain Tree (Samanea Saman) Residue As Modified Adsorbent To Treat Oil And Grease In Canteen Wastewater, Elga Riesta Puteri

Chulalongkorn University Theses and Dissertations (Chula ETD)

The utilization of waste materials as adsorbent precursors is gaining intention to treat fats, oils, and greases (FOG), especially in wastewater treatment. Tree residue, an abundant waste, provides a potential feedstock to be converted into valuable materials. This research aimed to develop modified adsorbent prepared from rain tree (Samanea saman) residue for FOG treatment. The synthesis process of modified adsorbent was conducted by chemical pretreatment using different chemical agents (i.e., NaOH, ZnCl2, and H3PO4­). The pre-treated twigs and leaves (1:4 ratio) were continued by pyrolysis process at different temperatures (i.e., 350, 550, and 750oC) using a heating rate of 10oC …

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Surface Activation Of Rice Husk-Derived Hydrochar As An Adsorbent For Atrazine And Ammonium, Kim Anh Phan Jan 2021

Surface Activation Of Rice Husk-Derived Hydrochar As An Adsorbent For Atrazine And Ammonium, Kim Anh Phan

Chulalongkorn University Theses and Dissertations (Chula ETD)

Due to the agricultural intensity, studies of sustainable solutions for atrazine and nitrogen contamination have attracted more attention. This study is aimed to develop rice husk hydrochar as an adsorbent for atrazine and ammonium adsorption. Effects of microwave-assisted hydrothermal carbonization (MHTC) conditions including temperature (150 – 200°C), residence time (20 – 60 min), and liquid to solid ratio (5:1 – 15:1 mL/g) on the atrazine and ammonium adsorption capacity were investigated. Surface activation of rice husk hydrochar samples was synthesized using potassium hydroxide (KOH) and hydrogen peroxide (H2O2) with various concentrations. The results showed that higher MHTC temperature with higher …

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Changes In Surface Water And Sediment Quality At A Complex Tidal-Influenced River: A Case Study Of Ganh Hao River, Mekong Delta, Vietnam, Muoi Le Van Jan 2021

Changes In Surface Water And Sediment Quality At A Complex Tidal-Influenced River: A Case Study Of Ganh Hao River, Mekong Delta, Vietnam, Muoi Le Van

Chulalongkorn University Theses and Dissertations (Chula ETD)

The research was carried out to determine the extent of surface water and sediment pollution using the physicochemical parameters and heavy metal concentrations. The surface water and sediment samples were obtained from 25 sites along the river on March 22 and September 5, 2019 at the main river influenced by the complex tidal regime and aquaculture practices in Ca Mau peninsular in the Vietnamese Mekong Delta. The water quality was compared with international and national standards, while the sediment quality was compared with Vietnamese standards and pollution indices (geo-accumulation index, contamination factor, and pollution load index). Principal component analysis (PCA) …

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