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2017

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Performance Comparison Of Multifunctional Reactors For Biodiesel Production From Transesterification Of Palm Oil, Tanutporn Laosuttiwong Jan 2017

Performance Comparison Of Multifunctional Reactors For Biodiesel Production From Transesterification Of Palm Oil, Tanutporn Laosuttiwong

Chulalongkorn University Theses and Dissertations (Chula ETD)

Biodiesel is classified as a qualified alternative energy that can be used for diesel engine. It is produced via transesterification of vegetable oil with alcohol in presence of homogeneous or heterogeneous catalyst. However, oil and alcohol are not totally miscible leading to slow reaction rate. Multifunctional reactors, especially cavitational reactors, are proposed to overcome this issue. The cavitational reactors include ultrasonic reactor and homogenizer reactor. In this work, ultrasonic reactor, homogenizer reactor and conventional magnetic stirred reactor were used to investigate and compare biodiesel yield and the efficiency in terms of biodiesel yield based on the energy consumption at different …

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Catalytic Hydrogenation Of Carbon Dioxide For Hydrocarbon Synthesis, Nuttakorn Boreriboon Jan 2017

Catalytic Hydrogenation Of Carbon Dioxide For Hydrocarbon Synthesis, Nuttakorn Boreriboon

Chulalongkorn University Theses and Dissertations (Chula ETD)

Catalytic hydrogenation can turn CO2 into hydrocarbon fuel. The development of the catalysts for CO2 hydrogenation has become important since the catalysts are critical for selective production of more higher hydrocarbons for practical application. In this work, the titania supported monometallic and bimetallic Fe-M (M = Co and Cu) catalysts were synthesized and tested for CO2 hydrogenation at 573 K and 1.1 MPa. Among the monometallic catalysts (Fe, Co and Cu/TiO2), only Fe/TiO2 catalyst exhibited some selectivity to higher hydrocarbons, while Co/TiO2 and Cu/TiO2 catalysts were highly selective only to CH4 and CO, respectively. The addition of a small amount …

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Hydrogen Rich Gas Production From Pyrolysis-Gasification Of Biomass With Combined Catalyst And Sorbent, Teerayut Bunma Jan 2017

Hydrogen Rich Gas Production From Pyrolysis-Gasification Of Biomass With Combined Catalyst And Sorbent, Teerayut Bunma

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this work, the hydrogen production during biomass steam pyrolysis-gasification with a combined catalysts and sorbent (catalyst/sorbents) was studied in a drop tube two-stages fixed bed reactor. The catalyst/sorbents were prepared by an excess-solution impregnation method. A nickel oxide (NiO)/magnesium oxide (MgO)/calcium oxide(CaO) catalyst/sorbents containing 10 wt. % NiO, 5 wt. % MgO and 5 wt. % CaO on gamma alumina (γ-Al2O3) showed the best activity in sorption enhanced hydrogen production (SEHP) for the pyrolysis-gasification of sugarcane leaves. Besides, the highest H2 concentration and the lowest CO2 concentration were attained using the Mg5Ni10Ca5 catalyst/sorbents. Because Mg5Ni10Ca5 catalyst/sorbents provided the dominant …

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Nanomaterial Sensors For Selective Detection Of Biothiol Compounds, Chiraporn Chaicham Jan 2017

Nanomaterial Sensors For Selective Detection Of Biothiol Compounds, Chiraporn Chaicham

Chulalongkorn University Theses and Dissertations (Chula ETD)

Novel nanomaterial sensors have been designed two different strategies of sensing approach. The first sensing system, the aggregation nanomicelles (TSC and TSD) were synthesized for GSH sensing based on disulfide-cleavaged trigger in the micelle. The result showed a large quenching fluorescent intensity around 587 nm and 528 nm corresponding to TSC and TSD, respectively, upon the addition of GSH in 2.5% DMSO/PBS at pH 6. Additionally, the benefit of TSD is utility for the distance-based fluorescence detection of 3D paper analytical device (3D-µPAD) for the detection of GSH. Apart from GQDs sensors base, we demonstrated the utility and board applicability …

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Photocatalytic Conversion Of Glycerol To Dihydroxyacetone, Trin Jedsukontorn Jan 2017

Photocatalytic Conversion Of Glycerol To Dihydroxyacetone, Trin Jedsukontorn

Chulalongkorn University Theses and Dissertations (Chula ETD)

This work was carried out to convert glycerol to value-added compounds in liquid phase over TiO₂-based photocatalyst. The investigated parameters were catalyst dosage (1-3 g/L), H₂O₂ concentration (0.3-1.5 mol/L), UV light intensity (1.1-4.7 mW/cm²), reaction time (4-8 h) and electron acceptor types (O₂ and H₂O₂). It was found that TiO₂ in anatase phase can achieved the glycerol conversion of around 71.42% at catalyst dosage of 3 g/L, H₂O₂ concentration of 1.5 mol/L, UV light intensity 4.7 mW/cm² and reaction time 8 h. The addition of monometallic (bismuth, platinum, palladium, and gold) and bimetallic (gold-bismuth, gold-platinum, and gold-palladium) on TiO₂ can …

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Synthesis And Optical Properties Of Pyrrolidinyl Peptide Nucleic Acid Carrying Fluorescence Nucleobases, Duangrat Nim-Anussornkul Jan 2017

Synthesis And Optical Properties Of Pyrrolidinyl Peptide Nucleic Acid Carrying Fluorescence Nucleobases, Duangrat Nim-Anussornkul

Chulalongkorn University Theses and Dissertations (Chula ETD)

Pyrrolidinyl peptide nucleic acid bearing D-prolyl-2-aminocyclopentanecarboxylic acid backbone (acpcPNA) is a nucleic acid mimic that shows superior binding affinity, stability and specificity to complementary DNA than the original PNA. This research focuses on the development of hybridization responsive fluorescence acpcPNA probes bearing fluorescent nucleobases that exhibit fluorescence increase upon hybridization to a specific nucleobase in the DNA target. The acpcPNA carrying the fluorescent nucleobases were synthesized via two different approaches, namely 1) pre-synthesized fluorescence PNA monomer as a building block that was subsequently incorporated into the PNA by solid phase synthesis and 2) post-synthetic modification of acpcPNA carrying a reactive …

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Application Of Headspace-Gas Chromatography-Mass Spectrometry For Characterization Of Volatile Compounds In Chicken Eggs, Hanan Jehma Jan 2017

Application Of Headspace-Gas Chromatography-Mass Spectrometry For Characterization Of Volatile Compounds In Chicken Eggs, Hanan Jehma

Chulalongkorn University Theses and Dissertations (Chula ETD)

Volatile compounds in chicken eggs under the cold chain system and non-cold chain system were characterized by headspace-solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) combined with chemometrics. According to a central composite design, the following optimum HS-SPME extraction conditions were obtained: extraction temperature of 65 oC, extraction time of 45 min and the amount of NaCl of 0.4 g. In comparison of their mass spectrum and linear retention index from HS-SPME-GC-MS analysis, major volatile compounds found in egg samples included toluene, hexanal, nonanal and other minor volatile compounds were heptanal, octanal, decanal, benzaldehyde, 1-octen-3-ol and 2-ethyl-1-hexanol, with the types and amounts …

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Synthesis Of Cationic Cdse/Zns Quantum Dots And Applications In Dna Detection, Jamornpan Yangcharoenyuenyong Jan 2017

Synthesis Of Cationic Cdse/Zns Quantum Dots And Applications In Dna Detection, Jamornpan Yangcharoenyuenyong

Chulalongkorn University Theses and Dissertations (Chula ETD)

Semiconductor nanoparticles or quantum dots (QDs), especially CdSe/ZnS QDs, are of great interest in bioapplications due to their unique size-dependent optical properties and photo-stability. One of the plausible applications of QDs is DNA detection using QDs as a novel fluorescence tool for sensing of DNA using the electrostatic interaction between negative charge of DNA and positive charge on QDs surface. In this work, CdSe/ZnS QDs were synthesized using a hot-solution decomposition process resulting in hydrophobic CdSe/ZnS QDs. To obtain water-soluble and cationic QDs, the surface of QDs were modified with poly(ethylene)imine (PEI) via micelle formation. Because of hydrophilicity of PEI …

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New Edta-Based Drug Delivery Carrier, Nathapong Pangkom Jan 2017

New Edta-Based Drug Delivery Carrier, Nathapong Pangkom

Chulalongkorn University Theses and Dissertations (Chula ETD)

Most of the anticancer drugs are insoluble in water, unspecified to target site and degradable under acidic conditions in the stomach, resulting in decreasing their activities and increasing the side effects. To overcome these problems, drug delivery carriers were used to overcome these problems. Most of the drug delivery carriers were prepared by polymeric micelle systems. However, that of polymeric micelle systems are difficult to synthesize into the random polymers, where different units are aligned on a polymer chain in a random manner, immature drug-incorporation technology and possible chronic liver toxicity due to slow metabolic process. Therefore, the enhancement of …

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Preparation Of Rigid Polyurethane Foams Catalyzed By Metal-Asparagine And Metal-Threonine Complexes, Nuttiya Jintana Jan 2017

Preparation Of Rigid Polyurethane Foams Catalyzed By Metal-Asparagine And Metal-Threonine Complexes, Nuttiya Jintana

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research aimed to synthesize metal-amino acid complexes in the form of aqueous solutions to serve as new catalysts for the preparation of rigid polyurethane foams. Aqueous solutions of metal-amino acid complexes were prepared from the reaction of metal acetates with amino acids and water was used as a solvent. Metal acetates employed were copper acetate and zinc acetate. Amino acids employed were asparagine (Asn) and threonine (Thr). Both amino acids are odorless and non-toxic. UV-Vis spectroscopy, FTIR spectroscopy and mass spectrometry were used to characterize metal-amino acid complexes. Metal-amino acid complexes, namely Zn(Asn)₂, Zn(Thr)₂, Cu(Asn)₂ and Cu(Thr)₂ (where Asn …

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Colorimetric Detection Of Cyanide Ions Using Complex Formation And Ctab-Coated Silica, Patita Salee Jan 2017

Colorimetric Detection Of Cyanide Ions Using Complex Formation And Ctab-Coated Silica, Patita Salee

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research presents a new colorimetric method of cyanide detection in solution and water samples based on the extraction of dicyano-bis-(1,10-phenanthroline)-iron(II) complex onto CTAB-coated silica. The complex was formed at pH 10 by using phosphate buffer via the complex formation between tris-(1,10-phenanthroline)-Iron(II) (ferroin) with cyanide ions in CTAB media. When the complex was extracted onto CTAB-coated silica, it resulted in a color change of the material from pale yellow to purple. The changing of color corresponded to cyanide concentration which could be observed by naked-eyes and the color intensity was determined by Image J. The effects of various parameters were …

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Fluoride Encapsulation In Calcium Matrix, Piyada Dissara Jan 2017

Fluoride Encapsulation In Calcium Matrix, Piyada Dissara

Chulalongkorn University Theses and Dissertations (Chula ETD)

Fluoride ion (F-) is an important ingredient in a toothpaste. It protects caries by reacting with hydroxyapatite [Ca10(PO)4(OH)2] in tooth enamel to form insoluble fluorapatite [Ca10(PO)4(F)2]. Unfortunately, F- also easily interacts with calcium species in a toothpaste, and then it is deactivated. In this work, we focus on the encapsulation of F- in a shellac bead by using a simple extrusion method. To construct shellac beads, an aqueous solution of F- is injected into an ethanolic solution of shellac. The shellac beads are formed due to insolubility of shellac in water. Then, the beads are transferred into DI water for …

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Ferrocene-Bearing Tea Polyphenol Particles As Anticancer Drug Carriers, Punnawich Phaiyarin Jan 2017

Ferrocene-Bearing Tea Polyphenol Particles As Anticancer Drug Carriers, Punnawich Phaiyarin

Chulalongkorn University Theses and Dissertations (Chula ETD)

Ferrocene is a redox moiety that can be positively charged upon being oxidized. Thus, it is possible to use this moiety to make a polymer platform that is redox responsive regarding their water solubility. Here we prepared polymerized EGCG nanoparticles (pEGCG) and polymerized EGCG gum (pEGCG-gum) from tea polyphenol EGCG. Ferrocene was grafted onto the polymerized tea polyphenol and the obtained polymers were allowed to self-assemble into water-insoluble and indispersible sub-micron particles. The water-insoluble ferrocene-bearing particles became water-dispersible particles with nanometer sizes upon being oxidized by hydrogen peroxide. The oxidized particles, Fc-pEG-gum can inhibit growth of HepG2 liver cancer cells …

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Colorimetric Detection Of Cysteine Using Silver-Hydroxyapatite Nanoparticles, Retno Prasetia Jan 2017

Colorimetric Detection Of Cysteine Using Silver-Hydroxyapatite Nanoparticles, Retno Prasetia

Chulalongkorn University Theses and Dissertations (Chula ETD)

Cysteine is a sulphur-containing amino acid that acts as an effective antioxidant in human body. An excessive amount of cysteine leads to cystine formation that causes the stone formation in kidney, bladder, and ureters. A new method was developed for detection of cysteine in urine samples based on the aggregation of silver nanoparticles (AgNPs) on Hydroxyapatite (HAp) in the presence of cysteine. Transmission Electron Microscope (TEM) was used to observe the morphology of prepared HAp and AgNPs on HAp. The presence of cysteine of different concentrations resulted in different cluster sizes of AgNPs on HAp and hence different solid color. …

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Synthesis And Supramolecular Polymerization Of Peptide Nucleic Acid-Containing Monomer, Ruttiyakorn Donthongkwa Jan 2017

Synthesis And Supramolecular Polymerization Of Peptide Nucleic Acid-Containing Monomer, Ruttiyakorn Donthongkwa

Chulalongkorn University Theses and Dissertations (Chula ETD)

Nucleobase-induced self-assembly interaction, have gained much attention as potential non-covalent driving force for generating interesting assembled structures. Pyrrolidinyl peptide nucleic acid (PNA), with (2′R,4′R)-prolyl/(1S,2S)-2-aminocyclopentanecarboxylic acid backbone (acpcPNA) has shown the recognition with complementary nucleic acids following Watson-Crick base rules. Another PNA system having different stereochemistry on proline ring with a backbone of (2′R,4′S)-prolyl/(1S,2S)-2-aminocyclopentanecarboxylic acid backbone (epi-acpcPNA) can undergo self-pairing. Here in this work, both acpcPNA- and epi-acpcPNA-functionalized monomers consisting of two PNA segments joined together by a flexible polyethylene glycol linker were prepared on solid support, purified by high performance liquid chromatography (HPLC) and characterized by MALDI-TOF mass spectrometry. The …

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Synthesis And Cytotoxicity Evaluation Of Gold Nanoparticles/Pullulan Derivatives For Cancer Treatment, Sakchai Laksee Jan 2017

Synthesis And Cytotoxicity Evaluation Of Gold Nanoparticles/Pullulan Derivatives For Cancer Treatment, Sakchai Laksee

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study focused on the development of multifunctional gold nanoparticles (AuNPs) using pullulan derivatives as a trifunctional reducing, stabilizing and capping agent for targeted delivery of camptothecin (CPT) or doxorubicin (DOX) in order to enhance their efficacy and reduce side effects. The surface of AuNPs was functionalized to contain 3 beneficial components on pullulan as followed: (i) quat188 as a positive charge to increase cellular uptake and activities, (ii) para-aminobenzoic acid (PABA) as a hydrophobic molecule to enhance biocompatibility, and (iii) folic acid (FA) as a targeting ligand to bind with folate receptor on cancerous cell membranes and enhance intracellular …

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Bioactive Compounds From Lichens And Mycobionts In Trypetheliaceae Family, Suekanya Jarupinthusophon Jan 2017

Bioactive Compounds From Lichens And Mycobionts In Trypetheliaceae Family, Suekanya Jarupinthusophon

Chulalongkorn University Theses and Dissertations (Chula ETD)

Chemical constituents of two lichens Marcelaria cumingii and Trypethelium subeluteriae, and four cultured mycobionts from M. cumingii, T. platystomum, T. eluteriae and Trypethelium sp. (Trypetheliaceae) were explored. Their secondary metabolites were structurally elucidated by spectroscopic methods as xanthones, anthraquinones, naphthoquinones and phenalenones. Lichexanthone, parietin, xanthorin and emodin were disclosed as constituents of lichens M. cumingii. Whereas, two anthraquinones: parietin and emodin could be isolated from T. subeluteriae together with another anthraquinone, haematommone. The chemical compositions of four cultured mycobionts were found to totally differ from those from lichen. The phenalenone bipolaride C was derived from T. platystomum while two 1,2-naphthoquinones, …

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Colorimetric Determination Of Thiocyanate Ion Using Modified Polymer Resins, Sujinda Khaosaard Jan 2017

Colorimetric Determination Of Thiocyanate Ion Using Modified Polymer Resins, Sujinda Khaosaard

Chulalongkorn University Theses and Dissertations (Chula ETD)

A new method for thiocyanate determination in milk samples based on the formation of dithiocyanato dipyridine copper(II) [Cu(SCN)2(Py)2] complex on polymer resin surface is proposed. Amberlite XAD-7 resin on was modified with copper-pyridine complex and used as the material for detection. The color of resin changed from blue to green with the increase of thiocyanate concentration. It could be observed by naked-eye and the color intensity used as quantitative data was measured via Image-J software. The effect of various parameters was investigated including Cu2+ concentration, time for resin modification with reagents, sample volume, detection time and pyridine volume. Under the …

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Design And Synthesis Of Selenium Nanoparticles To Overcome Multiple Drug Resistance Of Cancer Cells, Urarika Luesakul Jan 2017

Design And Synthesis Of Selenium Nanoparticles To Overcome Multiple Drug Resistance Of Cancer Cells, Urarika Luesakul

Chulalongkorn University Theses and Dissertations (Chula ETD)

The objective of this research is to synthesize selenium nanoparticles (SeNPs) stabilized by chitosan as a drug carrier for delivery doxorubicin to overcome drug-resistant in cancer cells. One important mechanism of multidrug resistance (MDR) includes decreased drug influx and increased drug efflux, leading to insufficient drug concentration to kill cancer cells. Therefore, to overcome MDR by increasing cellular uptake, the surface of SeNP was functionalized to provide 3 structural features: (i) a positive charge to improve their solubility, (ii) gallic acid, a hydrophobic molecule to enhance biocompatibility and (iii) folic acid, a targeting molecule to target cancer cells and enhance …

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Synthesis Of Thiofuranosides By Dehydrative Glycosylation In Micellar Media, Trichada Ratthachag Jan 2017

Synthesis Of Thiofuranosides By Dehydrative Glycosylation In Micellar Media, Trichada Ratthachag

Chulalongkorn University Theses and Dissertations (Chula ETD)

Green and aqueous-based dehydrative glycosylation of thiofuranosides in micellar media was developed. The thiofuranosides are useful as precursors for carbohydrate synthesis, biological active molecules, and bio-surfactants. Dodecylbenzenesulfonic acid (DBSA), a commercially available Brønsted acid-surfactant, was employed to increase solubility of substrates and enhance rate of the glycosylation. Herein, we report the dehydrative glycosylation of furanosides and pyranosides with aliphatic, aromatic, and heterocyclic thiols in aqueous media to afford the thiofuranosides. Microwave irradiation led to improved yields and shorter reaction times. Other reaction parameters such as temperature and the amount of acid used were also optimized. Aliphatic and aromatic thiofuranosides were …

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Characterization Of Non-Volatile Compounds In Tom Yum Soup Using High Performance Liquid Chromatography-Tandem Mass Spectrometry, Wanabud Wongbubpha Jan 2017

Characterization Of Non-Volatile Compounds In Tom Yum Soup Using High Performance Liquid Chromatography-Tandem Mass Spectrometry, Wanabud Wongbubpha

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this work, high performance liquid chromatography hyphenated with tandem mass spectrometry (HPLC-MS/MS) was developed and validated for simultaneous determination of 31 targeted non-volatile compounds, such as 2 organic acids, 20 amino acids and 9 phenolic acids, in Tom Yum ingredient, Tom Yum soup made from the fresh ingredients and commercial Tom Yum pastes, where the main Tom Yum ingredients include galangal, lemongrass, kaffir lime leaves, Bird's eye chili, lime juice and fish sauce. The following HPLC-MS/MS conditions were used: a PoroShell C18 column (4.6 x 100 mm, 2.7 µm) using a gradient elution of A:B mobile phase at a …

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Synthesis And Development Of Dipicolylamine Derivatives As New Fluorescent Chemosensors, Waroton Paisuwan Jan 2017

Synthesis And Development Of Dipicolylamine Derivatives As New Fluorescent Chemosensors, Waroton Paisuwan

Chulalongkorn University Theses and Dissertations (Chula ETD)

Di-2-picolylamine (DPA) is a powerful chelator for many transition metal ions. In this thesis, new DPA fluorescent chemosensors consisting of a fluorophore such as either naphthalimide or quinoline are developed. The first part deals with the synthesis of 1,8-naphthalimide derivatives linked 2-, 3-, 4-((bis(pyridin-2-ylmethyl)amino)methyl)aniline, and 4-amino-2-((bis(pyridin-2-ylmethyl)amino)methyl)phenol. The metal ion sensing experiments showed N3D was selective toward Ag+ with fluorescent enhancement in aqueous emitting green fluorescence under blacklight. The complexation of [N3D+Ag+] is a 1:1 stoichiometric binding with a limit of detection (LOD) 0.67 µM. Second part is the synthesis of oxazolidinonyl DPA derivatives by using self-developed halo-induced cyclization followed by …

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Metabolic Responses Of Aspergillus Niger Es4 To Ethanol Stress, Wimonsiri Kongchai Jan 2017

Metabolic Responses Of Aspergillus Niger Es4 To Ethanol Stress, Wimonsiri Kongchai

Chulalongkorn University Theses and Dissertations (Chula ETD)

Aspergillus niger ES4 is a fungus isolated from the top wall of an ethanol tank of the PTT public company limited. Because normally, microorganism cannot tolerate high amount of ethanol, the growth of A. niger ES4 on the ethanol tank indicates the special properties of this fungal strain in response to ethanol. This research was therefore aimed at studying the effects of ethanol on the metabolites production of A. niger ES4 by using both untargeted and targeted metabolomics. When A. niger ES4 cultures were grown in minimal media containing 4% of ethanol for 3 days, A. niger ES4 responded to …

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Factors Affecting Building Damage And People's Preparedness For Earthquake In Chiang Rai, Narongdej Intaratchaiyakit Jan 2017

Factors Affecting Building Damage And People's Preparedness For Earthquake In Chiang Rai, Narongdej Intaratchaiyakit

Chulalongkorn University Theses and Dissertations (Chula ETD)

On May 5, 2014, an earthquake with a magnitude of 6.3 on the Richter scale occurred in Chiang Rai, Thailand. This earthquake was the strongest earthquake in Thailand at the Mae Lao District region. It also caused building damage and casualties. In this research, 277 participants living in village no.2 and village no.7 of Dong Mada, a sub-district at Mae Lao district in Chiang Rai, were selected. A questionnaire was used to interview these participants, and the data were analyzed by Chi-square, Fisher's exact test, a Mann-Whitney U test, and a Kruskal-Wallis test. The objective of this study was to …

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Contact Problems With Surface Stress Effects, Supakorn Tirapat Jan 2017

Contact Problems With Surface Stress Effects, Supakorn Tirapat

Chulalongkorn University Theses and Dissertations (Chula ETD)

This dissertation presents a theoretical study of contact problems with consideration of surface energy effects by adopting a complete Gurtin-Murdoch theory of surface elasticity. The fundamental solution of a layered elastic half-space subjected to axisymmetric surface loading is obtained by using Love's representation and the Hankel integral transform. The analytical solutions for both displacement and stress fields are expressed in terms of semi-infinite integrals, which can be accurately evaluated by employing a numerical quadrature scheme. The obtained solutions are employed as the required influence functions in the investigation of axisymmetric indentation on a layered elastic medium with frictionless and adhesive …

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Mechanisms Of Thai Medicinal Plant Extracts On The Attenuation Of Glutamate-Mediated Neurotoxicity, Anchalee Prasansuklab Jan 2017

Mechanisms Of Thai Medicinal Plant Extracts On The Attenuation Of Glutamate-Mediated Neurotoxicity, Anchalee Prasansuklab

Chulalongkorn University Theses and Dissertations (Chula ETD)

As the world population ages, neurodegenerative diseases, particularly Alzheimer's disease, are becoming a major public health concern with increasing incidence and prevalence worldwide while no cure currently exists. To challenge this situation, herbal medicine may provide a potential alternative treatment as use of natural-derived substances has been proven to be effective in the prevention and/or treatment of several diseases. During the past decades, increasing evidence has implicated excessive glutamate levels in the pathway of neuronal cell death. Thailand is a place known for cultivating a variety of tropical plants and herbs, so far many of them have never been examined …

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Effects Of Plant Extracts On Melanin Biosynthesis And Melanogenetic Gene Expression In B16f10 Melanoma Cells, Moragot Chatatikun Jan 2017

Effects Of Plant Extracts On Melanin Biosynthesis And Melanogenetic Gene Expression In B16f10 Melanoma Cells, Moragot Chatatikun

Chulalongkorn University Theses and Dissertations (Chula ETD)

Ultraviolet radiation from sunlight is a significant environmental factor in skin damage and can induce hyperpigmentation disorder and aesthetic problem. Development of novel whitening phytochemical compounds from natural products has been become trends recently. The purpose of this study was to find some plant extracts that reduce melanin synthesis and melanogenetic gene expression in alpha-MSH-induced B16F10 mouse melanoma cells. To screen total phenolics and flavonoids, antioxidant activity, and anti-mushroom tyrosinase activity, we used 13 plants which were extracted with petroleum ether, dichloromethane and ethanol solvents, subsequently. We found that total phenolic content of 13 plants extracts was found in the …

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Role Of Progesterone Receptor A And B Isoforms In Lung Neuroendocrine Tumors, Teeranut Asavasupreechar Jan 2017

Role Of Progesterone Receptor A And B Isoforms In Lung Neuroendocrine Tumors, Teeranut Asavasupreechar

Chulalongkorn University Theses and Dissertations (Chula ETD)

Lung neuroendocrine tumors (NETs) incidences are increasing in recent years. Women with lung NETs have significantly better survival rates as compared to men suggesting the involvement of sex steroids and their receptors in the progression of lung NETs. Recent data suggested that progesterone receptor (PR) may play a role in the survival of lung NET patients. PR exists as two major isoforms, PRA and PRB. How expression of PR isoforms affects proliferation of lung NETs and patient's survival is not known. To determine the role of PR isoforms in lung NETs, we constructed H727 lung NET cell models expressing PRB …

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Protein Profiling Analysis Of Platelets In Hypercoagulable State Of Β-Thalassemia/Hbe Patients, Puangpaka Chanpeng Jan 2017

Protein Profiling Analysis Of Platelets In Hypercoagulable State Of Β-Thalassemia/Hbe Patients, Puangpaka Chanpeng

Chulalongkorn University Theses and Dissertations (Chula ETD)

β-thalassemia/HbE is an inherited hemolytic anemia caused by defect in β-globin synthesis resulting in accumulation of excess α-globin chains in red blood cells. A hypercogulable state leading to high risk of thromboembolic event is one of the most common complications observed in this disease, particularly in patients with splenectomy. Previous studies suggested that increased platelet activation and coagulation factors in β-thalassemia/HbE intermediate patients promote the hypercoagulable state. However, the hypercoagulable state as well as the molecular mechanism regarding this pathogenesis in β-thalassemia/HbE is not yet well understood. This study aimed to identify proteins related to platelet activation and to hypercoagulable …

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Comparison Between Digital Image Analysis And Visual Assessment Of Immunohistochemical Her2 Expression In Breast Cancer, Morten Ragn Jakobsen Jan 2017

Comparison Between Digital Image Analysis And Visual Assessment Of Immunohistochemical Her2 Expression In Breast Cancer, Morten Ragn Jakobsen

Chulalongkorn University Theses and Dissertations (Chula ETD)

Background: Assessment of HER2 status is considered standard of care in the histopathologic workup of breast cancer and conveys prognostic and predictive information used to guide treatment decisions. The assessment is often carried out in a two-step approach where immunohistochemical expression of HER2 protein is first evaluated by conventional microscopy and equivocal cases are further analyzed by in-situ hybridization techniques to assess gene amplification status. Methods: In this study we compared conventional manual assessment of immunohistochemical HER2 expression with digital image analysis (DIA) and consensus manual assessment by a panel of three pathologists. From our archive we retrieved sections of …

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