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2022

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Synthesis Of Furocoumarin Derivatives As Anti-Cancer Agents, Chiphada Aekrungrueangkit Jan 2022

Synthesis Of Furocoumarin Derivatives As Anti-Cancer Agents, Chiphada Aekrungrueangkit

Chulalongkorn University Theses and Dissertations (Chula ETD)

Furocoumarin derivatives are one of interesting scaffolds which show potential as an anti-cancer agent. The previous work has found the anticancer activity especially of the methoxsalen (8-MOP) derivatives with an amide group at the C-5 position. However, the scope of the substituents in the previous study on this scaffold remains lacking. Additionally, despite the promising anticancer properties of these furocoumarin derivatives, the information about mechanism of action or target enzymes is still inconclusive. Herein, a series of furocoumarin derivatives with C-5 substitution were successfully synthesized and evaluated for their in vitro cytotoxicity against eight cancer cell lines: breast cancers (MDA-MB-231 …

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Electrochemical Cyclization Of Chalcones For Synthesis Of Flavones, Taweesak Gulchatchai Jan 2022

Electrochemical Cyclization Of Chalcones For Synthesis Of Flavones, Taweesak Gulchatchai

Chulalongkorn University Theses and Dissertations (Chula ETD)

Flavone is considered as one of the important compounds in pharmaceutical and medicinal fields due to the existence of various biological activities, leading to various flavone synthetic methods. Even though most of the reported methods are efficient, they involve the use of harsh conditions, strong oxidizing agents, expensive metal catalysts, hazardous solvents, or multistep synthesis of starting materials. To overcome these limitations, in this work, we developed a novel electrochemical cyclization reaction for the synthesis of flavones from easy-access 2’-hydroxychalcones. In this electrochemical cyclization, platinum plates were used as electrodes in ethanol/water solvent under open air and room temperature in …

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Dosimetric Comparison Between Single-Energy Ct And Dual-Energy Ct For Relative Stopping Power Estimation In Proton Therapy, Thamonwan Chirdchid Jan 2022

Dosimetric Comparison Between Single-Energy Ct And Dual-Energy Ct For Relative Stopping Power Estimation In Proton Therapy, Thamonwan Chirdchid

Chulalongkorn University Theses and Dissertations (Chula ETD)

In proton therapy treatment planning, dose calculation requires CT calibration curve by relating CT number (HU) to relative stopping power to water (RSP). The CT calibration curve and the RSP validation are described for single-energy CT (SECT) and dual-energy CT (DECT). The focus of this work was given on the dosimetric comparison of treatment plans between SECT and DECT-based dose calculation. The 062M CIRS phantom was scanned to access the HU values by GE kVp switching method with single-energy of 120 kVp and dual-energy of 80/140 kVp. The CT calibration curve was generated using the stoichiometric calibration method and implemented …

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The Study Of Local Diagnostic Reference Levels Of Computed Tomography Procedures At Phramongkutklao Hospital, Sutasinee Mahasub Jan 2022

The Study Of Local Diagnostic Reference Levels Of Computed Tomography Procedures At Phramongkutklao Hospital, Sutasinee Mahasub

Chulalongkorn University Theses and Dissertations (Chula ETD)

Computed Tomography (CT) is a medical modality of 3D imaging technique using the X-ray photons rotate, transmit and detect the radiation by the multi-detectors. The CT examination results in the higher patient dose than the general radiography. The objective of this study was to establish the Local DRLs of patient radiation dose in CT procedures at Phramongkutklao Hospital. This study is a retrospective analysis at a single center from January-August 2021. Two CT scanners: 160 slices MDCT manufactured by Canon, model AquilionTM Prime and 640 slices MDCT manufactured by Canon, model AquilionTM One Prism have been used to collect the …

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Automated Method Of Corrected Effective Diameter For Ssde In Thoracic Imaging Ct Using Cnn, Sakultala Ruenjit Jan 2022

Automated Method Of Corrected Effective Diameter For Ssde In Thoracic Imaging Ct Using Cnn, Sakultala Ruenjit

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study aimed to automatically determine the corrected effective diameter (Deffcorr) using convolutional neural network (CNN) for simplified SSDE calculation in thoracic CT. Transaxial images of 108 adult patients underwent thoracic CT without contrast at King Chulalongkorn Memorial Hospital (KCMH) were collected. To calculate the Deffcorr according to Mihailidis et al., the average relative electron densities for lung tissue (ρelung=0.3), for other tissues (ρetissue=1.0) and for bone (ρebone=1.2) were employed to correct the lateral and anteroposterior dimension. The CNN network architecture based on the U-Net algorithm was used for automated image segmentation. The 108 thoracic CT images and generated segmentation …

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ความสัมพันธ์ระหว่างประสิทธิภาพการใช้น้ำกับปัจจัยทางสิ่งแวดล้อมของพรรณไม้ในเมืองในพื้นที่สีเขียวเขตเมือง บริเวณจุฬาลงกรณ์มหาวิทยาลัย, นิศาชล กุลสิริลักษณ์ Jan 2022

ความสัมพันธ์ระหว่างประสิทธิภาพการใช้น้ำกับปัจจัยทางสิ่งแวดล้อมของพรรณไม้ในเมืองในพื้นที่สีเขียวเขตเมือง บริเวณจุฬาลงกรณ์มหาวิทยาลัย, นิศาชล กุลสิริลักษณ์

Chulalongkorn University Theses and Dissertations (Chula ETD)

ปัจจุบันมีการพัฒนาพื้นที่สีเขียวในเมืองเพื่อเป็นที่พักผ่อนหย่อนใจและให้บริการเชิงนิเวศอย่างต่อเนื่อง ทำให้เกิดพื้นที่สีเขียวที่มีอายุการก่อตั้งแตกต่างกัน อันประกอบด้วยพืชพรรณและไม้ต้นที่มีขนาดและอายุต่างกัน ซึ่งอาจมีการตอบสนองต่อการเปลี่ยนแปลงของปัจจัยสิ่งแวดล้อมต่างกัน ได้แก่ สภาพอากาศและความชื้นในดิน การทราบรูปแบบการตอบสนองของต้นไม้ในสวนสาธารณะที่มีอายุนับตั้งแต่ก่อตั้งต่างกันอาจช่วยเป็นข้อมูลในการดูแลต้นไม้รวมถึงการเลือกพันธุ์ไม้ที่เหมาะสมต่อวัตถุประสงค์ของพื้นที่สีเขียวให้พื้นที่นั้นมีประสิทธิภาพมากยิ่งขึ้น งานวิจัยนี้จึงสนใจศึกษาประสิทธิภาพการใช้น้ำ ซึ่งหมายถึงปริมาณคาร์บอนที่สังเคราะห์ได้ต่อหน่วยหนึ่งการใช้น้ำ หรือน้ำที่รดให้แก่ต้นไม้ โดยศึกษาเบื้องต้นในระดับใบ คำนวณจากอัตราส่วนระหว่างการสังเคราะห์ด้วยแสงต่อการคายน้ำของใบของจามจุรี ชมพูพันธุ์ทิพย์ และปีบ ในสองพื้นที่ที่มีอายุในการก่อตั้งแตกต่างกัน ได้แก่ พื้นที่สีเขียวบริเวณจุฬาลงกรณ์มหาวิทยาลัย (CU) ซึ่งมีอายุในการก่อตั้งมากกว่า 80 ปี และ อุทยาน 100 ปี จุฬาลงกรณ์มหาวิทยาลัย (CU100) ซึ่งเป็นสวนสาธารณะแห่งใหม่ที่เพิ่งสร้างได้ประมาณ 5 ปี โดยมีวัตถุประสงค์เพื่อศึกษาการแลกเปลี่ยนแก๊สและประสิทธิภาพการใช้น้ำ และความสัมพันธ์ของค่าเหล่านี้กับปัจจัยทางสิ่งแวดล้อมของต้นไม้ทั้ง 3 ชนิดที่กล่าวมา ผลการศึกษาพบว่า จามจุรีและชมพูพันธุ์ทิพย์ในพื้นที่ CU100 มีอัตราการแลกเปลี่ยนแก๊สสูงกว่าพื้นที่ CU ในฤดูฝน อาจเป็นเพราะต้นไม้ในพื้นที่ CU มีอายุมากกว่า ประกอบด้วยขนาดต้นไม้ใหญ่กว่า และดินในพื้นที่ CU มีน้ำขัง ทำให้ค่าดังกล่าวต่ำกว่าพื้นที่ CU100 แต่ไม่พบความแตกต่างของค่าดังกล่าวของปีบใน 2 พื้นที่ ซึ่งอาจเป็นเพราะปีบเป็นไม้ที่ทนต่อสภาพแวดล้อมที่ต่างกันได้ดี รูปแบบความสัมพันธ์ระหว่างการแลกเปลี่ยนแก๊สและประสิทธิภาพการใช้น้ำกับภาวะพร่องความดันไอระหว่างใบกับอากาศเป็นไปตามรูปแบบสมการลอการิทึมในต้นไม้ทั้ง 3 ชนิด และมีรูปแบบการตอบสนองของค่าประสิทธิภาพการใช้น้ำนั้นเหมือนกันในสองพื้นที่ แม้จะมีค่าต่างกันระหว่างพื้นที่ในจามจุรีและชมพูพันธุ์ทิพย์ก็ตาม แสดงให้เห็นว่าต้นไม้ทั้ง 3 ชนิดอาจมีการปรับตัวให้เข้ากับสภาพแวดล้อมมาในช่วงเวลาหนึ่งแล้วจึงมีรูปแบบตอบสนองต่อสภาพอากาศที่คล้ายคลึงกันของสองพื้นที่ ดังนั้น หากจะพิจารณาถึงชนิดไม้ที่จะเลือกมาปลูกในพื้นที่สีเขียวแห่งใหม่ อาจพิจารณาเพียงค่าประสิทธิภาพการใช้น้ำที่สูง กล่าวคือให้ผลผลิตเชิงคาร์บอนได้มากต่อหน่วยปริมาณน้ำที่รดเท่ากัน โดยต้นไม้เหล่านี้สามารถปรับตัวให้เข้ากับสภาพแวดล้อมได้เมื่อให้เวลาเติบโตสักระยะ

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Influence Of Temperature Variation On Community Structure Of Ammonia-Oxidizing Microorganisms And Ammonia Oxidation Performance Under Low Substrate Environment, Napong Songkriengkrai Jan 2022

Influence Of Temperature Variation On Community Structure Of Ammonia-Oxidizing Microorganisms And Ammonia Oxidation Performance Under Low Substrate Environment, Napong Songkriengkrai

Chulalongkorn University Theses and Dissertations (Chula ETD)

The objectives of this study were to evaluate effect of temperature on ammonia removal efficiency and community structure of ammonia oxidizers including ammonia oxidizing archaea (AOA), ammonia oxidizing bacteria (AOB), and complete ammonia oxidizer (comammox). The bioreactors were set up using the seed sludge from municipal and industrial WWTPs. The bioreactors were fed with inorganic medium containing ammonia as the only energy source and were operated with continuous-flow mode without sludge recycling under low ammonia loading condition. The temperature of the bioreactors was varied at 10.5, 14, 17.5, 21, 35, 38.5, 42, and 45.5°C together with the control bioreactor operated …

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Pretreatment Of Polylactic Acid (Pla) Plastics By Uv-C Irradiation, Biosurfactants And Deep Eutectic Solvent (Des) To Enhance Biodegradation, Patamavadee Treeson Jan 2022

Pretreatment Of Polylactic Acid (Pla) Plastics By Uv-C Irradiation, Biosurfactants And Deep Eutectic Solvent (Des) To Enhance Biodegradation, Patamavadee Treeson

Chulalongkorn University Theses and Dissertations (Chula ETD)

Polylactic acid (PLA) is an interesting alternative to petroleum-based plastic due to its compostability. However, PLA requires around six months to two years to be degraded in conventional compost and natural environment. To enhance the biodegradation of PLA by a bacterial consortium (Nocardiodes zeae EA12, Stenotrophomonas pavanii EA33, Gordonia desulfuricans EA63, and Chitinophaga jiangningesis EA02), this study applied UV-C irradiation and surface coating with biosurfactants and deep eutectic solvent (DES) as pretreatment steps. The PLA film deterioration after UV-C exposure was analyzed by the reduction in viscosity average molecular weight, tensile properties, and ATR-FTIR spectroscopy. The deterioration and hydrophilicity of …

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Development Of Electrochemical Sensor For L-Hydroxyproline And Interleukin-6 Detections, Whitchuta Jesadabundit Jan 2022

Development Of Electrochemical Sensor For L-Hydroxyproline And Interleukin-6 Detections, Whitchuta Jesadabundit

Chulalongkorn University Theses and Dissertations (Chula ETD)

This dissertation is research on the development of biosensors using different types of bioreceptors and nanomaterials for the diagnostic application of various diseases. The research is separated into two parts. The first part is about the development of an enzyme-free impedimetric sensor based on molecularly imprinted polymer (MIP) for the selective determination of L-hydroxyproline (L-hyp), a biomarker of bone diseases. It was found that the use of a mixture containing 3-aminophenylboronic acid (3-APBA) functions as a monomer and o -phenylene diamine (OPD) as a co-monomer can generate the specific MIP through electropolymerization. The detection is based on the increase of …

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Diboronic Acid On Aryl-Alkyne Platform For Fructose Detection, Natthapat Satsuphap Jan 2022

Diboronic Acid On Aryl-Alkyne Platform For Fructose Detection, Natthapat Satsuphap

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this work, the mono- (MB) and diboronate ester-based aryl-alkyne fluorescent sensors (DB) were synthesized via simple and facile pathway. The probe MB exhibited the strongest fluorescence emission at 598 nm under the excitation wavelength of 300 nm where the probe DB emitted the fluorescence at 607 nm upon the excitation wavelength of 350 nm. However, in the presence of saccharides, both sensors showed a little change in the fluorescence response. That means both sensors cannot be used for saccharide detection via fluorescence spectroscopy as the direct method. Alizarin red S (ARS), one of the catechol dyes, was used to …

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Arenes Production Via Hydrodeoxygenation Of Oxygenated Compounds Derived From Pyrolysis Of Biomass And Polyethylene Terephthalate Using Co/Tio2 Catalyst, Surachet Hongkailers Jan 2022

Arenes Production Via Hydrodeoxygenation Of Oxygenated Compounds Derived From Pyrolysis Of Biomass And Polyethylene Terephthalate Using Co/Tio2 Catalyst, Surachet Hongkailers

Chulalongkorn University Theses and Dissertations (Chula ETD)

Arising from the need for sustainable developments announced by the United Nations, converting biomass and waste plastic into fuels and chemicals has become an interesting topic, contributing to the reduction of solid waste and the generation of high-value products, closing the loop of the circular economy towards a sustainable and waste-free society. Herein, the production of green chemicals from hydrodeoxygenation (HDO) of oxygenated compounds derived from lignocellulosic biomass and waste plastics using Co-based catalysts has been investigated. Initially, two types of TiO2 (anatase [TiO2-A] and rutile [TiO2-R]) were compared in 4-propylguaiacol conversion. Both types of Co/TiO2 catalysts facilitated the HDO …

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Development Of Paper-Based Electrochemical Immunosensor For Sars-Cov-2 Detection, Jutamas Jaewjaroenwatana Jan 2022

Development Of Paper-Based Electrochemical Immunosensor For Sars-Cov-2 Detection, Jutamas Jaewjaroenwatana

Chulalongkorn University Theses and Dissertations (Chula ETD)

This dissertation aimed to develop a simple and low-cost electrochemical sensing platform for detecting SAR-CoV-2 antigen. The proposed sensor combined the innovative disposable paper-based immunosensor and cost-effective plant-based anti-SARS-CoV-2 monoclonal antibody, extracted from Nicotiana benthamiana. The cellulose nanocrystal was modified on screen-printed graphene electrode to provide the COOH functional groups on electrode surface, leading to the high ability for antibody immobilization. The quantification of the presence receptor binding domain (RBD) spike protein of SARS-CoV-2 was performed using differential pulse voltammetry by monitoring the changing current of [Fe(CN)6]3-/4- redox solution. The current change of [Fe(CN)6]3-/4- before and after the presence of …

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Delayed Lateral Flow Immunoassay For Determination Of Covid-19 Antigen, Pawanrat Srithong Jan 2022

Delayed Lateral Flow Immunoassay For Determination Of Covid-19 Antigen, Pawanrat Srithong

Chulalongkorn University Theses and Dissertations (Chula ETD)

The lateral flow immunoassay (LFIA) strip is one of the most attractive biosensing platforms for a point-of-care testing (POCT). However, the generally lack of sensitivity and inability to perform quantitative analysis has consequently limited its outreaches for more challenging applications, where detecting low analytic concentrations is required. To overcome such drawbacks, we propose a facile and straightforward alternative method utilizing a delayed hydrophobic barrier fabricated with trimethylsilyl cellulose (TMSC) to improve its sensitivity. The SARS-CoV-2 spike receptor-binding domain (SARS-CoV-2 SP RBD) antigen was chosen as a model analyte to demonstrate the superior detectability of this scheme. The novel device consists …

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Glycosylation Of N-Pentenyl Glycoside Activated By Bromodiethylsulfonium Salt, Supanat Buntasana Jan 2022

Glycosylation Of N-Pentenyl Glycoside Activated By Bromodiethylsulfonium Salt, Supanat Buntasana

Chulalongkorn University Theses and Dissertations (Chula ETD)

n-Pentenyl glycosides (NPGs) are a significant class of glycosyl donors with dual functionality, serving as both protecting groups for the anomeric hydroxyl and leaving groups upon activation with halonium activators such as N-bromosuccinimide (NBS) or N-iodosuccinimide (NIS). However, the activation of less reactive glycosyl donors with these reagents has proven to be sluggish and inefficient. Recently, bromodiethylsulfonium bromopentachloroantimonate (BDSB) has emerged as a highly efficient brominating reagent that can be readily prepared and purified through crystallization. In this study, we explored the potential of BDSB as a halonium activator for NPGs in chemical glycosylation reactions. By using BDSB as the …

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Seek, Picture Insect, Google Lens: An Analysis Of Popular Insect Identification Apps Using Photos Of Realistic Quality, Morgan Manderfield Jan 2022

Seek, Picture Insect, Google Lens: An Analysis Of Popular Insect Identification Apps Using Photos Of Realistic Quality, Morgan Manderfield

Department of Entomology: Distance Master of Science Projects

Photo-based identification apps for mobile devices have grown in popularity across many fields of organismal biology. While studies have shown that these apps show promise in fields such as botany and ornithology, there is much skepticism surrounding their accuracy and usefulness in entomology. While providing these apps with photos of high quality will undoubtedly lead to the highest accuracy rates, often users submit photos of average quality, e.g., in poor lighting, out of focus, from far away, etc. To quantify realistic accuracy rates of photo-based insect identification apps, this study analyzed three popular apps – Seek, Picture Insect, and Google …

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Angular Distribution Of Electron-Helium Scattering In The Presence Of A 1.17 Ev Laser Field, Brian N. Kim Jan 2022

Angular Distribution Of Electron-Helium Scattering In The Presence Of A 1.17 Ev Laser Field, Brian N. Kim

Theses and Dissertations--Physics and Astronomy

We have measured relative differential cross sections for 350 eV electrons scattered by a helium target in the presence of 1.17 eV photons from an Nd:YAG laser. We report an angular distribution of free-free electrons that were scattered elastically at angles between 15o and 80o and of free-free electrons that underwent the process of electron-impact excitation of helium to its unresolved (1s2s)1S and (1s2p)1P excited states at angles between 1o and 80o. Our experiments test the momentum transfer dependence and the relationship between elastic and inelastic scattering in the Kroll-Watson approximation. …

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An Energy-Integrated Analysis For Measuring The Anomalous Precession Frequency For The Muon G − 2 Experiment At Fermilab, Laura Kelton Jan 2022

An Energy-Integrated Analysis For Measuring The Anomalous Precession Frequency For The Muon G − 2 Experiment At Fermilab, Laura Kelton

Theses and Dissertations--Physics and Astronomy

In the search for physics beyond the Standard Model, the Muon g − 2 Experiment at Fermilab (E989) will make the most precise measurement of the anomalous magnetic moment of the muon, aμ. Improvements in precision come from both increased statistics and new techniques to significantly reduce previous systematic uncertainties. The muon aμ is determined by extracting both the anomalous spin precession frequency, ωa, and the average magnetic field sampled by the muons, B. Traditionally an energy threshold analysis method which requires reconstruction of decay positrons from the muon decay, μ+ → e+ …

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Milky Way Morphology Probed By 6d Astrometric Data From The Gaia Space Telescope, Joshua Taylor Harry Jan 2022

Milky Way Morphology Probed By 6d Astrometric Data From The Gaia Space Telescope, Joshua Taylor Harry

Theses and Dissertations--Physics and Astronomy

At varying height above and below the plane of the Milky Way, I have used astrometric methods to classify stars of different galactic components of the Milky Way - the thin disk, thick disk, and stellar halo. This work complements prior study of Milky Way sub-structure - notably involving number density and/or pairwise correlations - which demonstrate non-steady state effects in the galaxy, such as axial/north-south symmetry breaking or more complex phenomena like the Gaia snail. This has motivated my exploration of stellar population changes with height about the Milky Way mid-plane, and the study of symmetry in such changes …

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Elastic And Inelastic Compton Scattering From Deuterium At 61 Mev, Danula Godagama Jan 2022

Elastic And Inelastic Compton Scattering From Deuterium At 61 Mev, Danula Godagama

Theses and Dissertations--Physics and Astronomy

A Compton scattering experiment using deuteron as target nuclei was carried out at the HIγS free electron laser facility at Durham, NC, with the goal of extracting the electromagnetic scalar polarizabilities of the neutron, αn and βn. A beam of 61~MeV gamma photons with a narrow energy spread was incident on a liquid deuterium target. The scattered gamma rays were detected at three scattering angles, 55o, 115o and 150o. Backward-scattered gamma rays were detected using two large-volume NaI spectrometers with energy resolution (σE/E) better than 2%. The combined effect of …

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Neutron Spectroscopy Of The Parity-Violating 0.734 Ev Neutron Resonance In Lanthanum-139 In Preparation For The Noptrex Time Reversal Violation Experiment, Danielle Schaper Jan 2022

Neutron Spectroscopy Of The Parity-Violating 0.734 Ev Neutron Resonance In Lanthanum-139 In Preparation For The Noptrex Time Reversal Violation Experiment, Danielle Schaper

Theses and Dissertations--Physics and Astronomy

One of the most outstanding questions in physics is the matter-antimatter asymmetry of the Universe, resulting from excess baryogenesis processes during the early moments of the formation of the Universe. At present, the types of processes needed to explain this matter excess, so-called `CP-violating processes' are known to exist within the present framework of the Standard Model of particle physics. However, decades of research has shown that our understanding of the origin of these processes is incomplete, as we do not presently know of enough sources of CP-violating processes to account for the large baryon asymmetry that we observe. The …

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Extraction Of Deep Inelastic Cross Sections Using A 10.4 Gev Electron Beam And A Polarized Helium-3 Target, Murchhana Roy Jan 2022

Extraction Of Deep Inelastic Cross Sections Using A 10.4 Gev Electron Beam And A Polarized Helium-3 Target, Murchhana Roy

Theses and Dissertations--Physics and Astronomy

Experiment E12-06-121 at Jefferson Lab aims to do a precision measurement of the neutron spin structure function g2 using inclusive inelastic scattering of electrons over a large kinematic range of x and Q2. The third moment of the linear combination of the spin structure functions g1 and g2, d2, is one of the cleanest higher twist observables and contains information on quark-gluon correlations. It is connected to the "color polarizability" or "color Lorentz force" of the nucleon. The experimental data taking was successfully conducted in Hall C using a longitudinally polarized electron …

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Energy Integrated Ratio Analysis Of The Anomalous Precession Frequency In The Fermilab Muon G-2 Experiment, Ritwika Chakraborty Jan 2022

Energy Integrated Ratio Analysis Of The Anomalous Precession Frequency In The Fermilab Muon G-2 Experiment, Ritwika Chakraborty

Theses and Dissertations--Physics and Astronomy

The muon’s anomalous magnetic moment, aμ, provides a unique way for probing physics beyond the standard model experimentally as it gathers contributions from all the known and unknown forces and particles in nature. The theoretical prediction of aμ has been in greater than 3 σ tension with the experimental measurement since the results of the Muon g-2 Experiment at the Brookhaven National Laboratory (E-821) were published in the early 2000s with a precision of 540 ppb. To settle this tension, the new Fermilab Muon g - 2 Experiment (E-989) is currently taking data with the aim of …

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Understanding The Physics Of Galaxy Clusters Out To Their Virial Radii And Beyond, Arnab Sarkar Jan 2022

Understanding The Physics Of Galaxy Clusters Out To Their Virial Radii And Beyond, Arnab Sarkar

Theses and Dissertations--Physics and Astronomy

In the hierarchical structure formation model, galaxy clusters grow and evolve via mergers and accretion from the surrounding cosmic web, leaving distinctive marks in the gas properties, metallicity, and dynamical state at the outskirts of clusters, which needs to be probed to better understand the growth of a cluster. I probed the gas properties of four nearby galaxy groups MKW4, Antlia, RXJ1159, and ESO3060170 out to their virial radii using deep Suzaku and mostly snapshot Chandra observations. I found the gas entropy profiles of MKW4 follow a power-law at its outskirts - as expected from purely gravitational structure formation model. …

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Stellar Parameter Determination For The Mastar Stellar Library, Daniel J. Lazarz Jan 2022

Stellar Parameter Determination For The Mastar Stellar Library, Daniel J. Lazarz

Theses and Dissertations--Physics and Astronomy

Empirical libraries of stellar spectra represent a key ingredient needed for modeling the integrated spectra of stellar populations, such as galaxies, through a process called stellar population synthesis (SPS). In order to make use of such libraries, accurate stellar atmospheric parameter estimates are required. Here, I present a methodology that was developed to build a stellar parameter catalog to accompany the MaNGA stellar library (MaStar), a comprehensive collection of empirical, medium-resolution stellar spectra. This parameter catalog was constructed using a multicomponent χ2 fitting approach to match the MaStar spectra to models generated by interpolating the ATLAS9-based BOSZ models. The …

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Thermalization And Quantum Information In Conformal Field Theory, Ashish Kakkar Jan 2022

Thermalization And Quantum Information In Conformal Field Theory, Ashish Kakkar

Theses and Dissertations--Physics and Astronomy

The consequences of the constraints of conformal symmetry are far-reaching within
theoretical physics. In this dissertation we address a series of questions in conformal
field theory: 1) We calculate the spectrum of qKdV charges in a large central charge
expansion. 2) We determine the corrections to bulk information geometry from 1/N
contributions to holographic correlators. 3) We study the higher genus partitions
functions of CFTs associated with classical and quantum error-correcting codes.

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First Steps In The Small-Scale Structure Formation In The Universe: The Emergence Of Galaxies, Da Bi Jan 2022

First Steps In The Small-Scale Structure Formation In The Universe: The Emergence Of Galaxies, Da Bi

Theses and Dissertations--Physics and Astronomy

Galactic morphology in the contemporary universe results from the convergence of a long list of physical processes, not all of them yet fully understood and quantified. The universe exhibits a hierarchical structure: galaxies grow being immersed in dark matter (DM) halos, which in turn are fed by diffuse and filamentary accretion. I use a suite of very high-resolution zoom-in cosmological simulations of galaxies in order to study the assembly of galaxies at high redshifts, z ≥ 2, to quantify the role of environment and of the parent DM halos in this procss. My models have been chosen to lie within …

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Studies Of Time Variations Of The Magnetic Field In The Nedm@Sns Experiment, Mojtaba Behzadipour Jan 2022

Studies Of Time Variations Of The Magnetic Field In The Nedm@Sns Experiment, Mojtaba Behzadipour

Theses and Dissertations--Physics and Astronomy

It is thought that equal quantities of matter and antimatter were generated at the moment of the Big Bang. However, observations of the Universe show that there is a significant excess of matter over antimatter. The matter-antimatter asymmetry in the Universe (baryon to photon ratio) is observed to be of the order of 10-10 [1]. Baryogenesis is a possible explanation for the matter-antimatter asymmetry of the universe. In 1967, Sakharov proposed three criteria necessary for Baryogenesis. The three conditions are: 1) baryon number violation, 2) C and CP violation and 3) departure from thermal equilibrium. However, the Standard Model's …

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High Performance Data Acquisition And Analysis Routines For The Nab Experiment, David Mathews Jan 2022

High Performance Data Acquisition And Analysis Routines For The Nab Experiment, David Mathews

Theses and Dissertations--Physics and Astronomy

Probes of the Standard Model of particle physics are pushing further and further into the so-called “precision frontier”. In order to reach the precision goals of these experiments, a combination of elegant experimental design and robust data acquisition and analysis is required. Two experiments that embody this philosophy are the Nab and Calcium-45 experiments. These experiments are probing the understanding of the weak interaction by examining the beta decay of the free neutron and Calcium-45 respectively. They both aim to measure correlation parameters in the neutron beta decay alphabet, a and b. The parameter a, the electron-neutrino correlation coefficient, is …

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Data Acquisition, Analysis And Simulations For The Fermilab Muon G−2 Experiment, Fang Han Jan 2022

Data Acquisition, Analysis And Simulations For The Fermilab Muon G−2 Experiment, Fang Han

Theses and Dissertations--Physics and Astronomy

The goal of the new Muon g-2 E989 experiment at Fermi National Accelerator Laboratory (FNAL) is a precise measurement of the muon anomalous magnetic moment, aμ ≡ (g-2)/2. The previous BNL experiment measured the anomaly aμ(BNL) with an uncertainty of 0.54 parts per million (ppm). The discrepancy between the current standard model calculation of the aμ(SM) and the previous measurement aμ(BNL) is over 3σ. The FNAL Muon g-2 experiment aims at increasing the precision to 140 parts per billion (ppb) to resolve the discrepancy between the theoretical …

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Constraining The Star Formation Histories Of Galaxies In The Swift/Uvot + Manga (Swim) Value-Added Catalog, Nikhil Ajgaonkar Jan 2022

Constraining The Star Formation Histories Of Galaxies In The Swift/Uvot + Manga (Swim) Value-Added Catalog, Nikhil Ajgaonkar

Theses and Dissertations--Physics and Astronomy

Although our understanding about galaxy evolution has improved in the past few
decades, we still do not understand how galaxies suddenly stop forming stars and move towards a quiescent phase. In order to do that, we must derive the Star Formation Histories (SFHs) of galaxies, that trace the change in Star Formation (SF) inside the galaxy over the cosmic timescale. This is achieved by using a set of spatially resolved near-ultraviolet (NUV) and optical spectroscopic images of the galaxies. We generate the Swift/UVOT + MaNGA value added catalog (SwiM VAC; Molina et al., 2020b) which comprises 150 galaxies having a …

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