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Comparing The Success Rate Of Pleurodesis With Thoracoscopic Talc Poudrage Combined With Indwelling Pleural Catheter Versus Thoracoscopic Talc Poudrage In Patient With Malignant Pleural Effusion, A Randomized, Non-Inferiority Clinical Trial, Jitanong Sootlek
Chulalongkorn University Theses and Dissertations (Chula ETD)
Background: Malignant pleural effusion (MPE) can cause dyspnea symptoms that greatly impact a patient's quality of life. Talc pleurodesis or indwelling pleural catheter (IPC) insertion are two treatment options that can prevent recurrent MPE, alleviate dyspnea, and improve quality of life. However, talc pleurodesis requires a lengthy hospital stay, while IPC insertion is associated with lower pleurodesis success rates. Due to limited hospital bed capacity, we have devised a practical approach to managing MPE by combining TTP and IPC. Objective: This study aims to evaluate the efficacy of combined Thoracoscopic talc poudrage (TTP) and IPC compared to TTP alone in …
A Randomized Controlled Trial Comparing The Diagnostic Yield Of Using Rapid On-Site Cytology Evaluation (Rose) And Without Using Rose In Radial Probe Endobronchial Ultrasound (R-Ebus) Guided Sheath Transbronchial Lung Biopsy With Bronchial Brushing In Peripheral Pulmonary Lesions, Kulchamai Silathapanasakul
Chulalongkorn University Theses and Dissertations (Chula ETD)
BACKGROUND: Radial Probe Endobronchial Ultrasonography (RP-EBUS) guided transbronchial biopsy with bronchial brushing is an effective way of tissue assessment for evaluating peripheral lung lesion combined with Rapid on-site Evaluation (ROSE). Our study aimed to evaluate the efficacy of ROSE add on RP-EBUS guided sheath transbronchial lung biopsy to improve the overall diagnostic yield. OBJECTIVES: The purpose of this study was to compare the diagnosis yield of peripheral lung lesions or nodules from the ROSE add on Radial Probe Endobronchial Ultrasonography (RP-EBUS) guided sheath transbronchial biopsy with bronchial brushing compared to the control group. METHODS: In this prospective randomized controlled trial …
Comparison Of Extubation Success Between Prophylactic Helmet Niv And Facemask Niv In High Risk Postextubation Patients;A Randomized Controlled Trial, Napat Jirawat
Chulalongkorn University Theses and Dissertations (Chula ETD)
Background: Post-extubation respiratory failure is a common complication in planned extubated patients, which increases mortality, particularly in high-risk patients. Noninvasive ventilation (NIV) with a facemask effectively prevents post-extubation respiratory failure, but helmet NIV use immediately after extubation is still unproven. Objective: To compare the success rates of extubation with prophylactic helmet NIV and facemask NIV in the first 48 hours in patients at high risk of developing post-extubation respiratory failure. Methods: The study was a single-center randomized controlled trial. The data were analyzed for 114 patients at high risk of extubation failure between June 2022 and June 2023. Patients were …
Development Of An Artificial Intelligence Model For Prediction Of Dry Weight In Chronic Hemodialysis Patients And Assessment Of Its Accuracy Compared To Standard Bioelectrical Impedance Analysis, Nataphut Boonvisuth
Chulalongkorn University Theses and Dissertations (Chula ETD)
Proper determination of dry weight (DW) is crucial for achieving positive outcomes in hemodialysis (HD) patients. However, the traditional clinical assessment of DW (C-DW) is often inaccurate. Recently, bioimpedance spectroscopy (BIS) analysis using a Body Composition Monitor (BCM) device has emerged as a gold standard method for determining DW (BCM-DW). Despite its accuracy, the high cost of the BCM device limits its accessibility. To overcome this challenge, the current study proposes a machine learning (ML) model, which is a part of artificial intelligence (AI), to assess DW using available clinical and laboratory parameters. Objective: To develop an ML model for …
Evaluation Of Tissue Adequacy In Patients With Malignant Intrathoracic Lymphadenopathy Undergoing Combined Endobronchial Ultrasound-Guided Miniforceps Biopsy (Ebus-Mfb) And Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration (Ebus-Tbna) Compared To Ebus-Tbna Alone, Pipu Tavornshevin
Chulalongkorn University Theses and Dissertations (Chula ETD)
RATIONALE: EBUS-TBNA has become an effective way of tissue assessment for evaluating mediastinal lymph nodes. Identifying molecular mutations is a key to personalized management in malignant disease. The success of molecular analysis depends on adequate tissue specimens consisting of an absolute number of tumor cell counts and the neoplastic cell percentage (NCP) estimation. This study aimed to evaluate the efficacy of EBUS-MFB added on EBUS-TBNA to improve the tissue adequacy and the overall diagnostic yield. In this prospective study, patients with enlarged intrathoracic lymph nodes underwent EBUS-TBNA followed by EBUS-MFB. The tissue adequacy for molecular analysis required that the tissue …
Genetic Analysis Of Focal Segmental Glomerulosclerosis In Thailand, Suramath Isaranuwatchai
Genetic Analysis Of Focal Segmental Glomerulosclerosis In Thailand, Suramath Isaranuwatchai
Chulalongkorn University Theses and Dissertations (Chula ETD)
Background: The genetic variants spectra of focal segmental glomerulosclerosis (FSGS) vary among different populations. Here we described the clinical and genetic characteristics of biopsy-proven FSGS patients in Thailand. We also used special staining in renal biopsy tissue to describe protein expression related to the variants found by whole-exome sequencing (WES). Also, a functional study in cells was studied to investigate the etiologic evidence of the variants found by WES. Methods: Fifty-three unrelated FSGS patients without secondary causes were included in our study. Whole-exome sequencing (WES) was subsequently performed. Immunohistochemistry (IHC) staining method was used to characterize the morphology of renal …
Anxiety And Social Experience Stressors Of Lgbt In Thailand, Bunatta Aritatpokin
Anxiety And Social Experience Stressors Of Lgbt In Thailand, Bunatta Aritatpokin
Chulalongkorn University Theses and Dissertations (Chula ETD)
The enhancement of the quality of life, according to the Sustainable Development Goals set by the United Nations (UN-SDG), places importance in equality for all groups of people, in all aspects. In this regard, although the Thailand sphere has been praised for its efforts to demonstrate its progressiveness regarding equality for groups who are more vulnerable to stressors, in practice, it is still quite lacking which could cause issues with mental health, such as anxiety and other stressors. This descriptive cross sectional quantitative research study explores the anxiety and social experience stressors of once such group - those of different …
D-Lactic Acid Fermentation Platform From Oil Palm Trunk Sap By Sporolactobacillus Terrae Sbt-1, Naphatsawan Sukaiem
D-Lactic Acid Fermentation Platform From Oil Palm Trunk Sap By Sporolactobacillus Terrae Sbt-1, Naphatsawan Sukaiem
Chulalongkorn University Theses and Dissertations (Chula ETD)
Lactic acid is an organic acid that contains two enantiomers, L- and D-lactic acid, and is considered the most potential monomer for many industrial products. Lactic acid has versatile applications in the pharmaceutical, food, textile, chemical, and leather industries moreover in poly-lactic acid (PLA) manufacturing. While L-lactic acid is well known in many commercial products and studies, only a few studies on D-lactic acid were found. Lactic acid can be produced either by microbial fermentation or chemical synthesis. Approximately 90 percent of the total lactic acid produced worldwide is via microbial fermentation which provides an optically pure L- or D-lactic …
Phthalate Ester Biodegradation In Agricultural Soil Using Exogenous Bacterial Consortium Under Fertilizer Addition, Theodora Mega Putri
Phthalate Ester Biodegradation In Agricultural Soil Using Exogenous Bacterial Consortium Under Fertilizer Addition, Theodora Mega Putri
Chulalongkorn University Theses and Dissertations (Chula ETD)
Phthalate esters (PAEs) have been classified as a priority contaminant due to their endocrine-disrupting properties and abundance in the environment. Previously, several PAE-degrading consortia were enriched from landfill soil. This study aimed to initially select a consortium with efficient degradation activity, to characterize based on degradation kinetics and community dynamics, and to evaluate bioaugmentation feasibility while maintaining activity through continuous transfer. It was obtained based on enriched consortium selection that LF-NK-DEHP could simultaneously degrade 92.9% 100 mg l-1 DBP and 63.4% 100 mg l-1 DEHP within seven days. Kinetic degradation revealed DBP degradation by LF-NK-DEHP to fit the modified Gompertz …
High-Pressure Study Of Hybrid Organic-Inorganic Perovskites And Double Perovskites, Ardimas -
High-Pressure Study Of Hybrid Organic-Inorganic Perovskites And Double Perovskites, Ardimas -
Chulalongkorn University Theses and Dissertations (Chula ETD)
Hybrid and double perovskite have been of great attraction for optoelectronic devices. However, exploring a feasible method to enhance their optical abilities remains a considerable challenge. Here, the researcher reports the pressure-induced phase transition as an effective way to modify optoelectronic properties. The researcher successfully synthesized the hybrid perovskite (MAPbI3) and the double perovskite (Cs2TiBr6) by the inverse temperature crystallization (ITC) and solution method, respectively. the researcher studied the pressure dependence phase transition and photoluminescence (PL) by placing the sample into diamond anvil cells (DACs) through Raman spectroscopy. The first principles method was used to support the idea. The researcher …
Improving Quality Of Cvd Graphene Grown On The Copper Foil By Physical Polishing Electropolishing And Thermal Annealing Pretreatment Processes, Methawut Sirisom
Improving Quality Of Cvd Graphene Grown On The Copper Foil By Physical Polishing Electropolishing And Thermal Annealing Pretreatment Processes, Methawut Sirisom
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study optimized the pretreatment processes (physical polishing (PP), electropolishing (EP), and thermal annealing) for high-quality graphene growth on thin copper (Cu) foils. PP using Brasso solvent was applied to smoothen the substrate surface, followed by EP with H3PO4 to reduce rolling lines and surface contamination. The EP process involved different H3PO4 concentrations (30-60%) and etching times (60-120 seconds). After thermal annealing at 860-940 ºC, graphene growth was performed using direct-liquid-injection chemical-vapor deposition with cyclohexane (C6H12) as the carbon precursor and nitrogen as the carrier gas. The optimized conditions involved PP and EP with 45% H3PO4 concentration and 90 seconds …
Biopolymer Nanocomposites For Food And Healthcare Applications, Tatiya Siripongpreda
Biopolymer Nanocomposites For Food And Healthcare Applications, Tatiya Siripongpreda
Chulalongkorn University Theses and Dissertations (Chula ETD)
This dissertation focuses on development of biopolymers by integrating nanomaterials to improve the properties of pristine polymers for enhancing the performances of chemical sensors and laser desorption/ionization mass spectroscopy (LDI-MS) applied for food quality control health monitoring and biomedical applications. The dissertation is divided into 4 parts: the first part, polylactic acid and cellulose were used for dual detection platform of biogenic amines for food spoilage indication. Highly porous PLA film is fabricated by adding nanosized calcium carbonate resulted in high sensing element entrapment. On another side of platform, pristine cellulose is modified with graphene oxide and exploited a substrate …
Awareness Of Medical Doctor On Medication-Related Osteonecrosis Of The Jaw In Osteoporosis Patients, Nachapol Supanumpar
Awareness Of Medical Doctor On Medication-Related Osteonecrosis Of The Jaw In Osteoporosis Patients, Nachapol Supanumpar
Chulalongkorn University Theses and Dissertations (Chula ETD)
Antiresorptive drugs are widely used to treat osteoporosis. A serious adverse effect of these drugs is medication-related osteonecrosis of the jaw (MRONJ). By informing and educating patients about MRONJ, providing proper dental referral, and monitoring the oral health of patients who receive antiresorptive agents, physicians can reduce the risk of MRONJ. We investigated the awareness and clinical practices of physicians in Thailand with regard to MRONJ. Physicians who prescribed antiresorptive drugs for osteoporosis filled out an online self-administered questionnaire about demographic characteristics, awareness, and practices related to MRONJ. Most respondents agreed that antiresorptive drugs may cause MRONJ (92.3%), that poor …
Factors Influencing Quality Nursing Care At Hospitals In Indonesia, I Gede Juanamasta
Factors Influencing Quality Nursing Care At Hospitals In Indonesia, I Gede Juanamasta
Chulalongkorn University Theses and Dissertations (Chula ETD)
The study investigated whether patient-to-nurse ratio, working hours, nurse competence, environment, nurse satisfaction, and turnover intention influence inpatient quality nursing care in Indonesian hospitals. Aiken’s model and empirical evidence were adapted to construct the framework. A cross-sectional design and multistage sampling were employed. Five hundred-fifty registered inpatient department nurses from June to October 2022. They were involved in completing the seven-part questionnaires, include a demographic questionnaire, nurse staffing measurement form, Good Nursing Care Scale, Nurse Competence Scale, Practice Environment Scale, McCloskey/Mueller Satisfaction Scale, and Anticipated Turnover Scale. All questionnaires had acceptable psychometric properties, which included content validity, construct validity, and …
Knowledge, Attitudes, Behavior, And Expectation Of Thai Patients Toward Dental Treatment During Covid-19 Pandemic: An Online Survey, Paratcha Pingsuthiwong
Knowledge, Attitudes, Behavior, And Expectation Of Thai Patients Toward Dental Treatment During Covid-19 Pandemic: An Online Survey, Paratcha Pingsuthiwong
Chulalongkorn University Theses and Dissertations (Chula ETD)
Aerosol-generating procedures with contaminated saliva may pose a risk of disease transmission during the COVID-19 pandemic. COVID-19 preventive measures in dental clinics have evolved in response to the pandemic situation. This research investigated the effect of this pandemic on Thai patients' knowledge, attitudes, and behavior toward dental treatment. The online survey was distributed in June 2022. There were 978 participants in the study. The results showed that most participants had accurate knowledge about the COVID-19 transmission route in dentistry. The mean and median level of concern in the following issues were: contracting COVID-19 in daily life (3.06 and 3.03), contracting …
Effect Of Normal Saline In Different Concentration On Soft Tissue Healing Of Extraction Wound: A Clinical Study, Walailuk Kunthikarn
Effect Of Normal Saline In Different Concentration On Soft Tissue Healing Of Extraction Wound: A Clinical Study, Walailuk Kunthikarn
Chulalongkorn University Theses and Dissertations (Chula ETD)
Sodium chloride solution (NaCl) is regarded as the most suitable and recommended medical irrigation, because of the nontoxic and isotonic properties. The previous in vitro study showed that NaCl solution induced migration and extracellular matrix excretion from human gingival fibroblast. However, there is no report concerning the effect of rinsing extraction wound with NaCl solution in clinical trial study. This research study is split mouth single-blind randomized controlled clinical trial to investigate if rinsing with 0.9% and 1.8% NaCl solution on extraction wound can promote soft tissue healing. The operation was performed in 60 socket sites. The patients, who had …
The Effects Of Decellularized Extracellular Matrix Derived From Jagged1-Treated Human Dental Pulp Stem Cells On Biological Responses Of Stem Cells Isolated From Apical Papilla, Suphalak Phothichailert
The Effects Of Decellularized Extracellular Matrix Derived From Jagged1-Treated Human Dental Pulp Stem Cells On Biological Responses Of Stem Cells Isolated From Apical Papilla, Suphalak Phothichailert
Chulalongkorn University Theses and Dissertations (Chula ETD)
Objective: Indirect Jagged1 immobilization efficiently activates canonical Notch signaling in hDPSCs. This study aimed to investigate the characteristic of the Jagged1-treated hDPSCs-derived dECM and its biological activity on odonto/osteogenic differentiation SCAPs. Methods: Bioinformatic database of Jagged1-treated hDPSCs was analyzed by NetworkAnalyst. hDPSCs seeded on Jagged1 immobilized surface were maintained with N or OM followed by decellularization procedure, dECM-N or dECM-OM, respectively. SCAPs were reseeded on each dECM with either normal medium or OM. Cell viability was determined by MTT assay. Characteristics of dECMs and SCAPs were evaluated by SEM, EDX, immunofluorescent staining and alcian blue staining. A Multipotential differentiation assay. …
Effects Of The Orthodontic Miniscrew Geometric Design On The Bone Microdamage And Primary Stability, Panida Methawit
Effects Of The Orthodontic Miniscrew Geometric Design On The Bone Microdamage And Primary Stability, Panida Methawit
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study investigated the effects of the pitch (P) and thread shape on orthodontic miniscrew cortical bone microdamage. The relationship between microdamage and primary stability was examined. Ti6Al4V orthodontic miniscrews had custom-made thread heights (H) and pitch sizes and were classified into the following groups: HCPC (control); HCPN (with a narrower pitch); and HTPC (with a taller thread height) (HC = 0.12 mm; HT = 0.36 mm; PC = 0.60 mm; PN = 0.30 mm). The orthodontic miniscrews were inserted in the pilot hole of prepared 1.0-mm-thick tibia cortical bone, and the maximum insertion torque (MIT) and Periotest value (PTV) …
Prediction Of Future Caries In Toddlers Via Salivary Microbiome: A 1-Year Longitudinal Study, Ratcha Raksakmanut
Prediction Of Future Caries In Toddlers Via Salivary Microbiome: A 1-Year Longitudinal Study, Ratcha Raksakmanut
Chulalongkorn University Theses and Dissertations (Chula ETD)
Dental caries in children is the most common chronic oral disease that could disturb their quality of life including their development. Early prevention is a key approach to reducing the prevalence of early childhood caries. However, a reliable caries predictor, as an essential tool for targeted prevention that is important to this approach, is still lacking for infants before caries onset. Therefore, we aimed to develop the caries risk prediction model based on the salivary microbiome of caries-free 1-year-old children to predict caries onset at 1-year follow-up. Using a nested case-control design within a prospective cohort study, 30 saliva samples, …
Expression Of Superoxide Dismutase 3 (Sod3) During Orthodontic Tooth Movement In Rats, Phanchanit Jindarojanakul
Expression Of Superoxide Dismutase 3 (Sod3) During Orthodontic Tooth Movement In Rats, Phanchanit Jindarojanakul
Chulalongkorn University Theses and Dissertations (Chula ETD)
Hypoxia induces reactive oxygen species (ROS) production in periodontal tissues. Superoxide dismutase 3 (SOD3) is an enzyme protecting cells from ROS. This study investigated SOD3 expression and function during rat orthodontic tooth movement (OTM) and in hypoxia-exposed rat PDL cells. OTM of right maxillary first molars were performed in Sprague-Dawley rats for 1 and 14 days (n = 6 per group). SOD3 and HIF-1α expression were evaluated by immunohistochemistry. SOD3 effects on cell viability and proliferation, ROS production, and mRNA expression of Hif-1α, Rankl, and Opg in PDL cells and osteoclast differentiation were investigated under normoxia and hypoxia. SOD3 expression …
The Effect Of Nano-Silver Fluoride In Remineralization On Artificial Dentine Caries: An In Vitro Study, Peeraya Punpeng
The Effect Of Nano-Silver Fluoride In Remineralization On Artificial Dentine Caries: An In Vitro Study, Peeraya Punpeng
Chulalongkorn University Theses and Dissertations (Chula ETD)
The aim of this in vitro study was to compare the remineralization efficiency among Nano-silver fluoride 400 ppm (NSF400), 38% Silver diamine fluoride (38% SDF) and 5% Sodium fluoride (5% NaF) on artificial dentine caries in permanent molar or premolar teeth. The teeth were sectioned to obtain 120 specimens (3 x 3 x 2 mm3). After artificial caries were created, the lesion depth (LD) was measured using Micro-computed tomography (Micro-CT) (n=15 specimens/group), and the surface microhardness (SMH) was measured using a Knoop microhardness tester (n=15 specimens/group). Subsequently, all specimens were randomly assigned to four groups: Group 1) NSF400, Group 2) …
Evaluation Of Different Scaffolds For Bone Regeneration In Rat Calvarial Bone Defects, Jeerawit Sirakittiworapong
Evaluation Of Different Scaffolds For Bone Regeneration In Rat Calvarial Bone Defects, Jeerawit Sirakittiworapong
Chulalongkorn University Theses and Dissertations (Chula ETD)
Scaffold plays a key role in the context of tissue engineering. It not only provides a structural support for cells, but also creates an appropriate milieu for recruited cells, enhancing the therapeutic effects of cell-based treatments, and enabling the controlled release of biological cues such as growth factors. Collagen is widely used scaffold material in tissue engineering, particularly in periodontal and bone regeneration. Other natural polymers, however, have been developed and can be useful. Therefore, in this study, we aim to investigate the ability of four different natural polymers including collagen, chitosan, silk fibroin, and silk fibroin/gelatin hydrogel in promoting …
Protein Expression After Gingival Injection Of Messenger Rna Encoding Platelet-Derived Growth Factor-Bb In Ligature-Induced Rat Periodontitis, Pimphorn Meekhantong
Protein Expression After Gingival Injection Of Messenger Rna Encoding Platelet-Derived Growth Factor-Bb In Ligature-Induced Rat Periodontitis, Pimphorn Meekhantong
Chulalongkorn University Theses and Dissertations (Chula ETD)
As a new class of medicines, mRNA platform has proven to be safe and effective. The objective of this study was to investigate the effect of local inflammation on platelet derived growth factor-BB (PDGF-BB) expression after gingival injection of PDGF-BB mRNA in lipid nanoparticles (LNPs) in ligature-induced rat periodontitis and to examine the dose-dependent effect of gingival delivery of mRNA. 3-0 silk was placed around maxillary left second molar for two weeks and removed, while the corresponding molar on the right was non-ligated. Under stereomicroscope, a significant bone loss at ligature sites was observed as compared to the non-ligature sites, …
Application Of Core Annular Flow For Oil Transportation In Different Pipe Configurations Using Computational Fluid Dynamics, Cindy Dianita
Application Of Core Annular Flow For Oil Transportation In Different Pipe Configurations Using Computational Fluid Dynamics, Cindy Dianita
Chulalongkorn University Theses and Dissertations (Chula ETD)
The application of Core Annular Flow (CAF) has become an interesting solution in transporting heavy oil through pipeline because of its energy reduction and cost efficiency. Current study conducted a 3D computational fluid dynamic (CFD) to simulate CAF of oil-water in horizontal T- and Y-pipe junctions with two types of oil characteristic i.e., oil as Newtonian fluid and oil as non-Newtonian Carreau Fluid. The 2k factorial statistical experimental design was applied to investigate the effect of geometry on the flow performance. Eight cases were run with different diameter combinations and junction angle. The most attractive design was measured by the …
The Study Of Oxygenated Compounds For Oil Fingerprinting Application, Khairunisa Betariani
The Study Of Oxygenated Compounds For Oil Fingerprinting Application, Khairunisa Betariani
Chulalongkorn University Theses and Dissertations (Chula ETD)
Oil spills have a large impact on the marine and coastal environments. The characterization of petroleum or its products spilled in the environment to its source rocks is an important tool to assist in the resolution of issues of environmental impact and legal responsibility. The composition and physical properties of spilled oils have changed during the weathering process. Petroleum biomarkers is a tool for defining the origin of each oil, which is unique for each type of oil. In general, petroleum biomarkers (i.e., hopane group) are widely used for oil fingerprinting by following the NORDTEST methodology. Besides the hopane group, …
Selective Conversion Of Cellulose Into 5-Hydroxymethylfurfural Over Modified Zeolite Catalysts In A Biphasic Solvent System, Oluwaseyi Ojelabi
Selective Conversion Of Cellulose Into 5-Hydroxymethylfurfural Over Modified Zeolite Catalysts In A Biphasic Solvent System, Oluwaseyi Ojelabi
Chulalongkorn University Theses and Dissertations (Chula ETD)
Lignocellulosic biomass mainly composed of cellulose which can be transformed through various thermochemical processes such as catalytic depolymerization, acid-catalyzed dehydration, pyrolysis, gasification, etc., into high-value chemicals for sustainable development and bio-based economy. 5-Hydroxymethylfurfural (HMF) is one of the potential platform bio-chemicals that can be obtained directly from lignocellulosic biomass via catalytic depolymerization and/or acid-catalyzed dehydration using a bifunctional catalyst for the manufacture of various renewable products. Protonic zeolites are bifunctional solid acid catalysts and are well known for their remarkable properties. Their large surface area could enable molecules to diffuse in and out of their pore systems. Moreso, their acidic …
Improving Chromatographic Analysis Of Phenolic Compounds, Tarika Lomcharoenwong
Improving Chromatographic Analysis Of Phenolic Compounds, Tarika Lomcharoenwong
Chulalongkorn University Theses and Dissertations (Chula ETD)
Phenolic compounds are important chemicals and are applied in many fields. Moreover, they are found as contaminants in the environment. This research aimed to improve the chromatographic analysis of phenolic compounds and was divided into two parts. The first part focused on improving the separation of a mixture containing eighteen phenols using gas chromatography with derivatized cyclodextrin stationary phases. Results showed that all three cyclodextrin-based stationary phases, with different ring sizes, improved the separation of the mixture in comparison to polysiloxane OV-1701 stationary phase. The best separation was obtained from the small-size alpha-cyclodextrin with a capillary column of 15-meter long …
Preparation Of Cellulose Micro- And Nano Fibers From Bagasse Through Deep Eutectic Solvent System, Worapoj Phuckpetch
Preparation Of Cellulose Micro- And Nano Fibers From Bagasse Through Deep Eutectic Solvent System, Worapoj Phuckpetch
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study aimed to prepare the cellulose micro- and nanofibers (CMNFs) using green chemistry viewpoint. The CMNFs were fabricated from sugarcane bagasse (SCB) pulp through treatment with zinc chloride (ZnCl2) - lactic acid (LA) in deep eutectic solvent (ZnCl2-LA DES) followed by short time ultrasonication of the DES-treated fibers in water. Under the optimum condition, the SCB pulp at high solid loading of 6.25% was treated with ZnCl2-LA DES. Lactate functionalized CMNFs with 230-270 nm length and 15-16 nm width were resulted in more than 90% yield and up to 62.2% crystallinity. The results showed that ZnCl2-LA DES was a …
Deuteration Of Organic Compounds By Hydrothermal Process, Nattasiri Phaisarn
Deuteration Of Organic Compounds By Hydrothermal Process, Nattasiri Phaisarn
Chulalongkorn University Theses and Dissertations (Chula ETD)
Deuterium-labeled compounds are in great demand in many applications, especially as reference standards for various analytical techniques. The objective of this study is to develop two complementary methods for deuterium labeling of organic compounds including the hydrogen-deuterium exchange (HDx) and halogen-deuterium exchange (XDx) reactions under hydrothermal conditions. For HDx, several aliphatic, alicyclic, aromatic, heterocyclic, and amino acid compounds were used as model substrates to determine the reactivity pattern and scope of the reaction. It was found that the HDx at the ortho- and para-Hs of phenolic compounds and a-position of amino acids as well as certain heteroaromatic compounds occurred efficiently …
Stimulation Of Immune Response In Mice Using The Plant-Produced Sars-Cov-2 S1 Subunit Protein Linked To The Fc Region, Chalisa Panapitakkul
Stimulation Of Immune Response In Mice Using The Plant-Produced Sars-Cov-2 S1 Subunit Protein Linked To The Fc Region, Chalisa Panapitakkul
Chulalongkorn University Theses and Dissertations (Chula ETD)
Coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 made a devastating impact worldwide, and virus management is challenging owing to a lack of specific therapies or affordable vaccines, especially in low-and middle-income countries. Hence a low-cost and efficient vaccine is necessary. In the present study, the immunogenicity of the plant-produced S1 subunit protein of SARS-CoV-2 was investigated in order to utilize it as a subunit vaccine. The SARS-CoV-2 S1 subunit protein was fused with the Fc region of human immunoglobulin (IgG1) and expressed in tobacco plants in species of Nicotiana benthamiana plants by agroinfiltration. The …