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Full-Text Articles in Physical Sciences and Mathematics

Enhancing The Conformational Stability Of The Cl-Par-4 Tumor Suppressor Via Site-Directed Mutagenesis, Samjhana Pandey, Krishna K. Raut, Andrea M. Clark, Antoine Baudin, Lamya Djemri, David S. Libich, Komala Ponniah, Steven M. Pascal Jan 2023

Enhancing The Conformational Stability Of The Cl-Par-4 Tumor Suppressor Via Site-Directed Mutagenesis, Samjhana Pandey, Krishna K. Raut, Andrea M. Clark, Antoine Baudin, Lamya Djemri, David S. Libich, Komala Ponniah, Steven M. Pascal

Chemistry & Biochemistry Faculty Publications

Intrinsically disordered proteins play important roles in cell signaling, and dysregulation of these proteins is associated with several diseases. Prostate apoptosis response-4 (Par-4), an approximately 40 kilodalton proapoptotic tumor suppressor, is a predominantly intrinsically disordered protein whose downregulation has been observed in various cancers. The caspase-cleaved fragment of Par-4 (cl-Par-4) is active and plays a role in tumor suppression by inhibiting cell survival pathways. Here, we employed site-directed mutagenesis to create a cl-Par-4 point mutant (D313K). The expressed and purified D313K protein was characterized using biophysical techniques, and the results were compared to that of the wild-type (WT). We have …


Reduced Metal Nanocatalysts For Selective Electrochemical Hydrogenation Of Biomass-Derived 5-(Hydroxymethyl)Furfural To 2, 5-Bis(Hydroxymethyl)Furan In Ambient Conditions, Baleeswaraiah Muchharla, Moumita Dikshit, Ujjwal Pokharel, Ravindranath Garimella, Adetayo Adedeji, Kapil Kumar, Wei Cao, Hani Elsayed-Ali, Kishor Kumar Sadasivuni, Naif Abdullah Al-Dhabi, Sandeep Kumar, Bijandra Kumar Jan 2023

Reduced Metal Nanocatalysts For Selective Electrochemical Hydrogenation Of Biomass-Derived 5-(Hydroxymethyl)Furfural To 2, 5-Bis(Hydroxymethyl)Furan In Ambient Conditions, Baleeswaraiah Muchharla, Moumita Dikshit, Ujjwal Pokharel, Ravindranath Garimella, Adetayo Adedeji, Kapil Kumar, Wei Cao, Hani Elsayed-Ali, Kishor Kumar Sadasivuni, Naif Abdullah Al-Dhabi, Sandeep Kumar, Bijandra Kumar

Chemistry & Biochemistry Faculty Publications

Selective electrochemical hydrogenation (ECH) of biomass-derived unsaturated organic molecules has enormous potential for sustainable chemical production. However, an efficient catalyst is essential to perform an ECH reaction consisting of superior product selectivity and a higher conversion rate. Here, we examined the ECH performance of reduced metal nanostructures i.e., reduced Ag (rAg) and reduced copper (rCu) prepared via electrochemical or thermal oxidation and electrochemical reduction process, respectively. Surface morphological analysis suggests formation of nanocoral and entangled nanowire structure formation for rAg and rCu catalysts. rCu exhibits slight enhancement in ECH reaction performance in comparison to the pristine Cu. However, the rAg …


Thermotrophy Exploratory Study, James Weifu Lee Jan 2023

Thermotrophy Exploratory Study, James Weifu Lee

Chemistry & Biochemistry Faculty Publications

The question of whether environmental heat energy could be utilized as a source of energy for biological metabolism is the center of this exploratory research. In 1979, this author postulated a hypothesis for the existence of thermotrophs that could isothermally utilize environmental heat energy as a source of their energy on Earth. According to this hypothesis, the thermotrophs could be the first primitive forms of life in the early Earth environment. The chemotrophs and phototrophs that we currently are all well familiar with might have been evolved somehow from the primitive thermotrophs. Furthermore, all the organisms currently regarded as the …


Halogen Bonding Interactions Of Haloaromatic Endocrine Disruptors And The Potential For Inhibition Of Iodothyronine Deiodinases, Craig A. Bayse Jan 2023

Halogen Bonding Interactions Of Haloaromatic Endocrine Disruptors And The Potential For Inhibition Of Iodothyronine Deiodinases, Craig A. Bayse

Chemistry & Biochemistry Faculty Publications

Halogen bonding (XB) is a potential mechanism for the inhibition of the thyroid-activating/deactivating iodothyronine deiodinase family of selenoproteins through interactions with halogenated endocrine disrupting compounds (EDCs). Trends in XB interactions were examined using density functional theory for a series of polyhalogenated dibenzo-1,4-dioxins, biphenyls, and other EDCs with methylselenolate, a simple model of the Dio active site selenocysteine. The strengths of the interactions depend upon the halogen (Br>Cl), the degree of substitution, and the position of the acceptor. In terms of donor-acceptor energies, interactions at the meta position are often the strongest, suggesting a link to the topology of THs, …


Synthesis And Self-Assembling Properties Of Carbohydrate- And Diarylethene-Based Photoswitchable Molecular Gelators, Pramod Aryal, Joedian Morris, Surya B. Adhikari, Jonathan Bietsch, Guijun Wang Jan 2023

Synthesis And Self-Assembling Properties Of Carbohydrate- And Diarylethene-Based Photoswitchable Molecular Gelators, Pramod Aryal, Joedian Morris, Surya B. Adhikari, Jonathan Bietsch, Guijun Wang

Chemistry & Biochemistry Faculty Publications

Carbohydrate-based low-molecular-weight gelators are interesting new materials with many potential applications. These compounds can be designed to include multiple stimuli-responsive functional groups. In this study, we designed and synthesized several chemically responsive bola-glycolipids and dimeric carbohydrate- and diarylethene-based photoswitchable derivatives. The dimeric glycolipids formed stable gels in a variety of solvent systems. The best performing gelators in this series contained decanedioic and dithienylethene (DTE) spacers, which formed gels in eight and nine of the tested solvents, respectively. The two new DTE-containing esters possessed interesting photoswitching properties and DTE derivative 7 was found to have versatile gelation properties in many solvents, …


Extracting High-Molecular Weight Dna From Cyanobacteria Using Promega's Wizard® Hmw Dna Extraction Kit With A Modified Protocol, Metis, Megan A. Hept, Lesley H. Greene Jan 2023

Extracting High-Molecular Weight Dna From Cyanobacteria Using Promega's Wizard® Hmw Dna Extraction Kit With A Modified Protocol, Metis, Megan A. Hept, Lesley H. Greene

Chemistry & Biochemistry Faculty Publications

Extraction of high molecular weight (HMW) DNA for long read sequencing with little to no fragmentation and high purity is difficult to acquire from cyanobacterial species. Here we describe a modified method of extraction using Promega's Wizard® HMW DNA Extraction Kit to acquire high molecular weight DNA from cyanobacterial species. The protocol used in the kit is the “3.D. Isolating HMW DNA from Gram-Positive and Gram-Negative Bacteria” protocol. During a key step in the protocol, the lingering remnants of the mucilage layer of the cyanobacterial species is removed, preventing it from sticking to the DNA pellet produced. This customized modification …


S-Type Stars: Line List For The A²Π-X²Σ⁺ Band System Of Lao, P. F. Bernath, R. Dodangodage, J. Liévin Jan 2023

S-Type Stars: Line List For The A²Π-X²Σ⁺ Band System Of Lao, P. F. Bernath, R. Dodangodage, J. Liévin

Chemistry & Biochemistry Faculty Publications

LaO bands are found in the spectra of cool S-type stars. The bands of the A2Π–X2Σ+ transition with v' ⩽ 3 and v'' ≤ 4 are rotationally analyzed, providing spectroscopic constants for the A2Π state. Line strengths are calculated using an ab initio transition dipole moment function, and radiative lifetimes for the A2Π state have also been computed. A line list for the A2Π–X2Σ+ transition of LaO is provided and can be used to determine LaO stellar abundances.


Telp Theory: Elucidating The Major Observations Of Rieger Et Al. 2021 In Mitochondria, James Weifu Lee Jan 2023

Telp Theory: Elucidating The Major Observations Of Rieger Et Al. 2021 In Mitochondria, James Weifu Lee

Chemistry & Biochemistry Faculty Publications

The transmembrane-electrostatically localized protons (TELP) theory may represent a complementary development to Mitchell's chemiosmotic theory. The combination of the two together can now excellently explain the energetics in mitochondria. Our calculated transmembrane-attractive force between an excess proton and an excess hydroxide explains how TELP may stay within a 1-nm thin layer at the liquid-membrane interface. Consequently, any pH sensor (sEcGFP) located at least 2–3 nm away from the membrane surface will not be able to see TELP. This feature as predicted from the TELP model was observed exactly in the experiment of Rieger et al., 2021. In contrast to their …


Expanding Our Grasp Of Two-Component Signaling In Clostridioides Difficile, Orlando Berumen Alvarez, Erin B. Purcell Jan 2023

Expanding Our Grasp Of Two-Component Signaling In Clostridioides Difficile, Orlando Berumen Alvarez, Erin B. Purcell

Chemistry & Biochemistry Faculty Publications

The intestinal pathogen Clostridioides difficile encodes roughly 50 TCS, but very few have been characterized in terms of their activating signals or their regulatory roles. A. G. Pannullo, B. R. Zbylicki, and C. D. Ellermeier (J Bacteriol 205:e00164-23, 2023, https://doi.org/10.1128/jb.00164-23) have identified both for the novel C. difficile TCD DraRS. DraRS responds to antibiotics that target lipid-II molecules in the bacterial cell envelope, and regulates the production of a novel glycolipid necessary for bacitracin and daptomycin resistance in C. difficile.


One-Pot Iodine-Mediated Synthesis Of Cannabinol And Derivatives, Mongkonkorn Thanakorncharoenwit Jan 2023

One-Pot Iodine-Mediated Synthesis Of Cannabinol And Derivatives, Mongkonkorn Thanakorncharoenwit

Chulalongkorn University Theses and Dissertations (Chula ETD)

Cannabinol (CBN) is a minor cannabinoid that exhibits a broad range of medicinal activities without psychoactive effects. CBN derivatives have been typically synthesized from a terpenoid and a resorcinol derivative, through a multistep reaction including the Friedel-Crafts alkylation, cyclization, and aromatization. In this study, we envisioned that iodine could act as a Lewis acid catalyst and an aromatization agent. Consequently, we developed a one-pot iodine-mediated reaction between (1S,4R)-p-menthadienol and 5-(1,1-dimethylheptyl)resorcinol for the synthesis of 3-(1,1-dimethylheptyl)cannabinol (DMH-CBN). Various reaction parameters were evaluated, and the reaction yields were analyzed by quantitative 1H NMR. The optimized reaction conditions were found to be 1.5 …


Kinetic Mechanism Of Dimethylsulfone Monooxygenase And Its Immobilized Magnetic Nanoparticles, Montisa Mangkalee Jan 2023

Kinetic Mechanism Of Dimethylsulfone Monooxygenase And Its Immobilized Magnetic Nanoparticles, Montisa Mangkalee

Chulalongkorn University Theses and Dissertations (Chula ETD)

The dimethyl sulfone monooxygenase system is a two-component flavoprotein catalyzing the monooxygenation of dimethyl sulfone (DMSO2) by oxidative cleavage producing methanesulfinate and formaldehyde. The reductase component (DMSR) is a flavoprotein with FMN as a cofactor catalyzing flavin reduction using NADH. The oxygenase (DMSMO) uses reduced flavin from the reductase and oxygen for substrate monooxygenation. DMSMO can bind to FMN and FMNH– with a Kd of 17.4 ± 0.9 µM and 4.08 ± 0.8 mM, respectively. The binding of FMN to DMSMO is required prior to binding DMSO2. Substituting reduced DMSR with FMNH– demonstrated the same oxidation kinetics, indicating that FMNH- …


Development Of A Gel-Based Electrolyte For Determination Of Heavy Metals Using Smartphone, Nuntanuch Lersanantasit Jan 2023

Development Of A Gel-Based Electrolyte For Determination Of Heavy Metals Using Smartphone, Nuntanuch Lersanantasit

Chulalongkorn University Theses and Dissertations (Chula ETD)

Herein, a portable electrochemical device using biopolymeric gel-based electrolyte for the on-field simultaneous determination of Cd(II) and Pb(II) is presented. Pectin, a natural polymer, was used as a chemical delivery medium due to its biodegradation and fast-dissolving properties. Differential pulse voltammetry (DPV) was used to detect electrochemical signal of Cd(II) and Pb(II) solution dropped on the pectin-based electrolyte platform. The modification of screen-printed graphene electrode with Sb-Bi bimetallic alloy using both in situ and pre-mixed method was able to enhance the sensitivity of the sensor. The experimental results demonstrated that the developed gel-based electrolyte was capable of generating sharp and …


Molecular Assembly Of Hyaluronic Acid Nanoparticles For Drug Delivery By Molecular Dynamics Simulation, Pisit Lerttanakij Jan 2023

Molecular Assembly Of Hyaluronic Acid Nanoparticles For Drug Delivery By Molecular Dynamics Simulation, Pisit Lerttanakij

Chulalongkorn University Theses and Dissertations (Chula ETD)

Nanoparticles (NPs) offer a promising approach in modern medicine for the treatment of various diseases. They serve as effective carriers for various drugs including antibiotics, antivirals and anticancer agents. Hyaluronic acid-based nanoparticles (HA-NPs) have been interested owing to their exceptional biocompatibility and biodegradability. Hyaluronic acid (HA) is a natural biopolymer with versatile applications. However, there have been limited numbers of studies on molecular simulations of nanoparticles, particularly HA-NPs. In this study, molecular dynamics simulations were employed to explore molecular models representing the assembly of HA-NPs. Two types of HA-NPs, acetylated hyaluronic acid nanoparticles (AcHA-NPs) and hyaluronic acid-ceramide nanoparticles (HACe-NPs), were …


โปรตีนเข้มข้นจากโครงไก่: การเตรียมและการใช้ในผลิตภัณฑ์นักเก็ต, ชนากานต์ มณฑาทิพย์กุล Jan 2023

โปรตีนเข้มข้นจากโครงไก่: การเตรียมและการใช้ในผลิตภัณฑ์นักเก็ต, ชนากานต์ มณฑาทิพย์กุล

Chulalongkorn University Theses and Dissertations (Chula ETD)

งานวิจัยนี้มีวัตถุประสงค์เพื่อศึกษาภาวะที่เหมาะสมสำหรับการสกัดโปรตีนจากโครงไก่ เพื่อเตรียมโปรตีนเข้มข้นและนำมาศึกษาสมบัติทางเคมีกายภาพและสมบัติเชิงหน้าที่ของโปรตีนเข้มข้นจากโครงไก่และศึกษาผลของการเติมโปรตีนเข้มข้นต่อคุณภาพและเนื้อสัมผัสของผลิตภัณฑ์นักเก็ตไก่ ผลการศึกษาการสกัดโปรตีนด้วยสารละลายด่างที่ค่าความเป็นกรด-ด่าง 8.5 - 11.5 และระยะเวลาในการสกัด 30 - 300 นาที ด้วยวิธีพื้นผิวตอบสนองและการออกแบบการทดลองแบบส่วนผสมกลางพบว่าสมการการทำนายผลตอบสนองประสิทธิภาพในการผลิตโปรตีนเข้มข้นมีความเหมาะสมในการอธิบายความสัมพันธ์และทำนายค่าของตัวแปรอิสระให้มีความสัมพันธ์กับผลตอบสนองที่ต้องการ โดยค่าสัมประสิทธิ์การถดถอย (Regression coefficient) ของตัวแปรอิสระมีความสัมพันธ์กับประสิทธิภาพในการผลิตโปรตีนเข้มข้นในระบบฐานแห้ง (Dry basis) รวมถึงค่าสัมประสิทธิ์การตัดสินใจมีค่ามากกว่า 0.80 และมีค่า Root Mean Square Error (RMSE) ต่ำหมายความว่าค่าความแตกต่างเฉลี่ยกำลังสองระหว่างค่าที่ได้จากการทำนายกับค่าที่ได้จากการทดลองมีค่าต่ำ เมื่อพิจารณาค่า Adjusted r–Squared พบว่ามีค่าใกล้เคียงกับค่าสัมประสิทธิ์การตัดสินใจ การทำนายภาวะการสกัดโปรตีนจากโครงไก่จากการกำหนดเกณฑ์ของค่าประสิทธิภาพในการผลิตโปรตีนเข้มข้นสูงที่สุดพบว่าภาวะค่าความเป็นกรด-ด่างเท่ากับ 10.15 และระยะเวลาในการสกัดเท่ากับ 185 นาที เป็นภาวะที่เหมาะสมที่สุดสำหรับการสกัดโปรตีนจากโครงไก่ โดยค่าผลตอบสนองที่ได้จากการทำนายจากสมการมีความแตกต่างจากค่าที่ได้จากการทดลองเท่ากับ 12.67% เมื่อนำโปรตีนเข้มข้นที่ผลิตในภาวะที่เหมาะสมที่สุดมาทดสอบความสามารถในการอุ้มน้ำและค่าความสามารถในการเกิดอิมัลชันพบว่ายังมีความสามารถในการอุ้มน้ำต่ำกว่าเนื้อไก่ส่วนขาและส่วนอก (p < 0.05) จึงนำโปรตีนเข้มข้นมาพัฒนาสมบัติเชิงหน้าที่พบว่าการพัฒนาโปรตีนเข้มข้นด้วยกระบวนการปรับปรุงด้วยเกลือ ฟอสเฟตและความดันและการปรับปรุงด้วยเกลือ ฟอสเฟตและส่วนผสม (โปรตีนถั่วเหลืองไอโซเลท แป้งข้าวสาลี แป้งมันสำปะหลัง) และความดันส่งผลให้โปรตีนเข้มข้นมีความสามารถในการเกิดอิมัลชันและความสามารถในการคงตัวของอิมัลชันสูงกว่าโปรตีนเข้มข้นจากโครงไก่ที่ไม่ผ่านการปรับปรุงอยู่ในช่วงระหว่าง 6.03 - 12.27% และ 4.93 - 6.83% ตามลำดับ รวมถึงมีความสามารถในการละลายที่ดีกว่าเนื้อไก่ในช่วง pH เท่ากับ 6 - 7 เมื่อนำโปรตีนเข้มข้นเติมลงในผลิตภัณฑ์นักเก็ตไก่จะเห็นได้ว่าการเติมโปรตีนเข้มข้นที่สัดส่วนเท่ากับ 12.50% ส่งผลทำให้นักเก็ตไก่มีค่า Hardness, Gumminess และ Chewiness สูงกว่าสูตรปกติระหว่าง 3899.44 - 4324.59, 2676.22 - 3243.04 และ 2363.65 - 3011.87 g-force ในขณะที่ปริมาณโปรตีนและค่าสีของตัวอย่างนักเก็ตไม่มีความแตกต่างอย่างมีนัยสำคัญ (p ≥ 0.05) เมื่อเทียบกับสูตรควบคุม นอกจากนี้การใช้โปรตีนเข้มข้นมีส่งผลให้ประสิทธิภาพในการผลิตสูงกว่าสูตรปกติ โดยประสิทธิภาพในการผลิตของสูตรเติมโปรตีนเข้มข้นปรับปรุงด้วยเกลือ ฟอสเฟตและส่วนผสม (โปรตีนถั่วเหลืองไอโซเลท แป้งข้าวสาลี แป้งมันสำปะหลัง) และความดันมีค่าสูงที่สุดเท่ากับ 136.43% แต่อย่างไรก็ตามเมื่อพิจารณาจากต้นทุนในระดับ Commercial production scale พบว่าการเติมโปรตีนเข้มข้นด้วยกระบวนการปรับปรุงด้วยเกลือ ฟอสเฟตและความดันมีต้นทุนการผลิตต่ำที่สุด รวมถึงมีปริมาณโปรตีนและคุณภาพด้านสีไม่แตกต่างจากสูตรปกติ จึงเลือกโปรตีนเข้มข้นด้วยกระบวนการปรับปรุงด้วยเกลือ ฟอสเฟตและความดันเป็นกระบวนการปรับปรุงที่ดีที่สุด โดยในระยะเวลา 1 เดือนจะสามารถผลิตนักเก็ตไก่จากโปรตีนเข้มข้นได้ทั้งหมด 1250 กิโลกรัมและสามารถลดต้นทุนการผลิตได้ที่ 175 บาทต่อเดือน


การพัฒนาระบบเซลล์สุริยะติดตั้งบนหลังคา เพื่อใช้งานในสายการผลิตยางคอมปาว์ด, อินทุอร ธรรมสอน Jan 2023

การพัฒนาระบบเซลล์สุริยะติดตั้งบนหลังคา เพื่อใช้งานในสายการผลิตยางคอมปาว์ด, อินทุอร ธรรมสอน

Chulalongkorn University Theses and Dissertations (Chula ETD)

งานวิจัยนี้ได้ทำการศึกษา วิเคราะห์การใช้พลังงานของโรงงาน เพื่อออกแบบระบบเซลล์สุริยะบนหลังคา การกำหนดแผนงานติดตั้ง ศึกษาปัจจัยหลักที่ส่งผลกระทบต่อการผลิตไฟฟ้า และการประเมินประสิทธิภาพการใช้พลังงานไฟฟ้าจากเซลล์สุริยะจากการใช้งานเป็นแหล่งพลังงานสะอาดสำหรับกระบวนการผลิตยางคอมปาว์ด โดยออกแบบการใช้พลังงานไฟฟ้าให้เกิดประสิทธิภาพสูงสุดในอุตสาหกรรมผลิตยางคอมปาว์ด 2 โครงการ ระบบไฟฟ้าเซลล์สุริยะแบบออนกริดที่มีขนาดกำลังไฟฟ้าติดตั้งขนาด 865 กิโลวัตต์ และ 630 กิโลวัตต์ จากการศึกษาพบว่าทั้ง 2 โรงงานมีการใช้พลังงานไฟฟ้าในกระบวนการผลิตเป็นหลัก และความต้องการใช้พลังงานไฟฟ้าแปรผันตามยอดผลิตยางคอมปาว์ดร้อยละ 90 จากการวิเคราะห์ติดตามผลการใช้งานไฟฟ้าเซลล์สุริยะมีประสิทธิภาพต่ำกว่าร้อยละ 75 ในช่วงระยะ 5 เดือนหลัง เนื่องจากความต้องการใช้พลังงานไฟฟ้าของโรงงานลดลงและการจัดการโหลดการผลิตไม่เหมาะสมในช่วงกลางวัน และพบฝุ่นที่สะสมบนเซลล์สุริยะเป็น ผงคาร์บอน แคลเซียมคาร์บอนเนต และซิลิกาซึ่งเป็นส่วนผสมของการผลิตยางคอมปาว์ด จากการศึกษาพบว่า ฝุ่นจากกระบวนการผลิตส่งผลกระทบต่อการผลิตไฟฟ้าของเซลล์สุริยะร้อยละ 4 ดังนั้นระยะเวลาการล้างแผงเซลล์สุริยะของทั้ง 2 โครงการที่จุดสมดุลคือ ทุกๆ 3 เดือน จากการศึกษาข้อมูลการใช้ไฟฟ้าจากระบบเซลล์สุริยะนี้ชี้ให้เห็นว่า การผลิตไฟฟ้าของระบบเซลล์สุริยะแบบออนกริดนี้ มีปัจจัยหลักต่อการผลิตไฟฟ้าคือความต้องการใช้ไฟฟ้าของโรงงานเป็นหลัก เนื่องจากทั้ง 2 โรงงานมีการใช้ไฟฟ้าน้อยกว่ากำลังติดตั้งจึงทำให้เซลล์สุริยะผลิตไฟฟ้าน้อย แม้จะมีค่ารังสีดวงอาทิตย์สูงก็ตาม อย่างไรก็ตามระบบไฟฟ้าเซลล์สุริยะไม่สามารถจ่ายไฟฟ้าได้ตลอดเวลา ดังนั้นการบริหารจัดการโหลดการผลิตให้เหมาะสมจึงจำเป็นมาก เพื่อการใช้ไฟฟ้าจากเซลล์สุริยะให้มีประสิทธิภาพสูงสุด


Spatial And Temporal Varitations In Dissolved Calcium In The Kentucky Lake Watershed In Relation To Zebra Mussel Colonization, Kelsie Meystedt Jan 2023

Spatial And Temporal Varitations In Dissolved Calcium In The Kentucky Lake Watershed In Relation To Zebra Mussel Colonization, Kelsie Meystedt

Murray State Theses and Dissertations

Calcium is the fifth most abundant element on earth’s crust. Plants and animals require calcium for structure and intracellular metabolism. Recent studies have shown that dissolved calcium (Ca2+) freshwater ecosystems is of growing concern as the increasing concentrations of this element are implicated in altering the natural environment and biota. Elevated levels of dissolved calcium and sporadic re-emergence of an invasive species, namely zebra mussels (Dreissena polymorpha) in Kentucky Lake in the recent years served as a motivation for this study. The objective of this study was to determine spatial and temporal variations in dissolved calcium in selected streams, Kentucky …


Multiscale Molecular Modeling Studies Of The Dynamics And Catalytic Mechanisms Of Iron(Ii)- And Zinc(Ii)-Dependent Metalloenzymes, Sodiq O. Waheed Jan 2023

Multiscale Molecular Modeling Studies Of The Dynamics And Catalytic Mechanisms Of Iron(Ii)- And Zinc(Ii)-Dependent Metalloenzymes, Sodiq O. Waheed

Dissertations, Master's Theses and Master's Reports

Enzymes are biological systems that aid in specific biochemical reactions. They lower the reaction barrier, thus speeding up the reaction rate. A detailed knowledge of enzymes will not be achievable without computational modeling as it offers insight into atomistic details and catalytic species, which are crucial to designing enzyme-specific inhibitors and impossible to gain experimentally. This dissertation employs advanced multiscale computational approaches to study the dynamics and reaction mechanisms of non-heme Fe(II) and 2-oxoglutarate (2OG) dependent oxygenases, including AlkB, AlkBH2, TET2, and KDM4E, involved in DNA and histone demethylation. It also focuses on Zn(II) dependent matrix metalloproteinase-1 (MMP-1), which helps …


I. Preparation Of Strategic Synthetic Building Blocks For World Health Organization Essential Medicines. Ii. Applying The Principles Of Process Intensification To The Synthesis Of Fluoroquinolone Antibiotics., Jeffrey M. Noble Jan 2023

I. Preparation Of Strategic Synthetic Building Blocks For World Health Organization Essential Medicines. Ii. Applying The Principles Of Process Intensification To The Synthesis Of Fluoroquinolone Antibiotics., Jeffrey M. Noble

Theses and Dissertations

The synthesis of active pharmaceutical ingredients is often a time-consuming and expensive process. Due to the nature of pharmaceutical manufacturing, these costs are carried forward to the final purchase price by the consumer. Although there are many factors which are involved in the final costing of a pharmaceutical, the cost associated with the synthesis is the primary one which can be managed by chemists and engineers.

This work discusses the synthetic routes of four active pharmaceutical ingredients as well as the synthetic techniques and equipment used with an emphasis on how the application of specific techniques can be applied to …


Characterization And Evaluation Of Catalytic Activity Of Small Molecule Copper Complexes For Metallopolymer Design, Brenda Lu Jan 2023

Characterization And Evaluation Of Catalytic Activity Of Small Molecule Copper Complexes For Metallopolymer Design, Brenda Lu

Master's Theses

Catalysis is one of the driving forces in designing greener chemical processes for essential real-world applications. Enzymes, Nature’s catalysts, are known for their high selectivity, use of readily available metals and reagents, and ability to work under physiological conditions; three important qualities that synthetic chemists would like to mimic in their small molecule metal catalysts. Though most small molecule metal catalysts fall short of enzyme-like activity, we hypothesize that using a polymer scaffold as a secondary coordination sphere mimic around the metal complex will affect the microenvironment (steric and electronic) and enable enzyme-like activity. Previously, we synthesized ligand precursors and …


Optimizing Soluble Recombinant Expression Of The Aedes Aegypti Early Trypsin Protease, Neomi Millan Jan 2023

Optimizing Soluble Recombinant Expression Of The Aedes Aegypti Early Trypsin Protease, Neomi Millan

Master's Theses

The female Aedes aegypti mosquito is a primary vector for the transmission of blood–borne viral pathogens such as Chikungunya, Zika, Yellow Fever, and Dengue. The female mosquito will become infected with these pathogens through the uptake of a blood meal from an infected host. The midgut digestive enzymes are required to digest the blood meal to obtain necessary nutrients needed for the completion of the gonotrophic cycle. Blood meal digestion is biphasic and digestive enzymes are expressed at different time points after uptake of a blood meal. The focus of this study is on an early phase protease known as …


Analysis Of Laminar Flow Patterns In Milifluidic Devices, Brian Leger Jan 2023

Analysis Of Laminar Flow Patterns In Milifluidic Devices, Brian Leger

Honors Theses

This research centers around a millifluidic device designed for the analysis of flowing chemical reactions that may happen too quickly to be analyzed by traditional spectroscopic methods. The device works by combining two simple concepts: fluid flows a certain distance over time and chemical reactions progress over time. Combining these allows for the correlation of reaction progress and distance through the device. Since the flow within the device is laminar, there is friction along the walls of the channel that creates a flow profile that elongates over time. The details of the flow were previously unknown but are necessary if …


Biallelic Mutations In P4htm Cause Syndromic Obesity, Sadia Saeed, Lijiao Ning, Alaa Badreddine, Muhammad Usman Mirza, Mathilde Boissel, Roohia Khanam, Jaida Manzoor, Qasim M. Janjua, Waqas I. Khan, Bénédicte Toussaint, Emmanuel Vaillant, Souhila Amanzougarene, Mehdi Derhourhi, John F. Trant, Anna-Maria Siegert, Brian Y.H. Lam, Giles S.H. Yeo, Layachi Chabraoui, Asmae Touzani, Abhishek Kulkarni, I. Sadaf Farooqi, Amélie Bonnefond, Muhammad Arslan, Philippe Froguel Jan 2023

Biallelic Mutations In P4htm Cause Syndromic Obesity, Sadia Saeed, Lijiao Ning, Alaa Badreddine, Muhammad Usman Mirza, Mathilde Boissel, Roohia Khanam, Jaida Manzoor, Qasim M. Janjua, Waqas I. Khan, Bénédicte Toussaint, Emmanuel Vaillant, Souhila Amanzougarene, Mehdi Derhourhi, John F. Trant, Anna-Maria Siegert, Brian Y.H. Lam, Giles S.H. Yeo, Layachi Chabraoui, Asmae Touzani, Abhishek Kulkarni, I. Sadaf Farooqi, Amélie Bonnefond, Muhammad Arslan, Philippe Froguel

Chemistry and Biochemistry Publications

We previously demonstrated that 50% of children with obesity from consanguineous families from Pakistan carry pathogenic variants in known monogenic obesity genes. Here, we have discovered a novel monogenetic recessive form of severe childhood obesity using an in-house computational staged approach. The analysis included whole-exome sequencing data of 366 children with severe obesity, 1,000 individuals of the Pakistan Risk of Myocardial Infarction Study (PROMIS) study, and 200,000 participants of the UK Biobank to prioritize genes harboring rare homozygous variants with putative effect on human obesity. We identified five rare or novel homozygous missense mutations predicted deleterious in five consanguineous families …


Modification Of Hyaluronic Acid To Enable Click Chemistry Photo-Crosslinking Of Hydrogels With Tailorable Degradation Profiles, Ciara Buckley Jan 2023

Modification Of Hyaluronic Acid To Enable Click Chemistry Photo-Crosslinking Of Hydrogels With Tailorable Degradation Profiles, Ciara Buckley

Articles

Hyaluronic acid (HA) is a naturally occurring mucopolysaccharide that, due to its inherent bioactivity and extracellular matrix-like structure, has the potential to be utilised extensively in tissue engineering. However, this glycosaminoglycan lacks the properties required for cellular adhesion and photo-crosslinking by UV light, which significantly hinders this polymers applicability. This research presents a method for modifying hyaluronic acid via thiolation and methacrylation to generate a novel photo-crosslinkable polymer with improved physicochemical properties, biocompatibility and the potential to customize biodegradability according to the ratio of monomers used. A decrease in stiffness proportional to increasing thiol concentration was observed when testing the …


Antibiotic Susceptibility Of Proteus Mirabillis That Isolates Of Diabetic Foot Ulcers In Al- Diwaniyah Hospital, Aseel Hussein Jaber, Suaad A. Fazaa Almiyah Jan 2023

Antibiotic Susceptibility Of Proteus Mirabillis That Isolates Of Diabetic Foot Ulcers In Al- Diwaniyah Hospital, Aseel Hussein Jaber, Suaad A. Fazaa Almiyah

Al-Qadisiyah Journal of Pure Science

The current study have been included 250 samples diabetic foot ulcer patients attending in Al-Diwaniyah Teaching Hospital and private clinics at a period of study from beginning October 2021 to February 2022, Isolates were identified by morphological form on blood agar and macConkey agar, traditional biochemical tests and then confirmed by Vitek 2 system. The result of bacterial culture have been recorded that only 80 samples had positive result to P. mirabilis formed (32%) of this result. Prevalence of P. mirabilis isolates in male more than female (34.78%) and (28.57%) respectively, after then were determination of antibiotics susceptibility pattern of …


Candida Spp. Associated With Covid-19 And Its Susceptibility To Some Antifungals, Mohammed Mudhafar Alkhuzaie, Neeran Obied Jasim Jan 2023

Candida Spp. Associated With Covid-19 And Its Susceptibility To Some Antifungals, Mohammed Mudhafar Alkhuzaie, Neeran Obied Jasim

Al-Qadisiyah Journal of Pure Science

The aim of this study was to conduct a survey of the Candida species associated with COVID-19 viral infection in 150 patients who were admitted to the intensive care unit (ICU) in Al-Diwaniyah Teaching Hospital in Al-Diwaniyah City, Iraq, for a five-month period from October 2021 to February 2022. The results indicated the dominance of Candida spp. over the rest of the isolated fungal species, with 97 isolates (64.66%). C. albicans was shown to be the most abundant species with a percentage of 55.67 percent (P 0.05), compared to the other Candida species that were isolated (Candida tropicalis 13.4 percent, …


Common Fixed Point Theorems By Using Two Mappings In B-Rectangular Metric Space, Qasim K. Kadhim Jan 2023

Common Fixed Point Theorems By Using Two Mappings In B-Rectangular Metric Space, Qasim K. Kadhim

Al-Qadisiyah Journal of Pure Science

In this paper, the aim to obtain the existence and uniqueness of some common fixed point theorem on b-rectangular metric space by using new conditions including rational, maximum, minimum and combination for two mappings.


Comparative Physiology Study Of Side Effect Between Xenical And Lipo-6 Supplements Which Treated Obese Rabbets, Hayder Ghazib Abdulshaheed Jan 2023

Comparative Physiology Study Of Side Effect Between Xenical And Lipo-6 Supplements Which Treated Obese Rabbets, Hayder Ghazib Abdulshaheed

Al-Qadisiyah Journal of Pure Science

Obesity is rapidly becoming a health problem, and it is considered a metabolic disease of epidemic proportions. Obesity is also associated with many comorbidities such as hyperlipidemia, fatty liver, atherosclerosis, cancer. Use of over-the-counter weight-loss supplements has become more common in the world; Xenical and Lipo-6 are two examples of nutritional supplements that do not pass safety research before being sold to the consumer. The ability of Xenical and lipo-6 supplements on DNA fragmentation in human lymphocytes was studied, where these cells represent important defense line of the body. On other hand, thirty white rabbits Iraqis in this experiment, weighing …


Correlation And Comparison Of Some Trace Elements And Their Related Proteins In Type 2 Diabetes Mellitus In Kalars City/ Kurdistan-Iraq, Hero Helal Muhammed Saed, Zeyan Abdullah Ali Jan 2023

Correlation And Comparison Of Some Trace Elements And Their Related Proteins In Type 2 Diabetes Mellitus In Kalars City/ Kurdistan-Iraq, Hero Helal Muhammed Saed, Zeyan Abdullah Ali

Al-Qadisiyah Journal of Pure Science

No abstract provided.


Cosemiprime Ring, Muntaha Abdul- Razaq Hasan Jan 2023

Cosemiprime Ring, Muntaha Abdul- Razaq Hasan

Al-Qadisiyah Journal of Pure Science

In this paper ,we introduce a new type of rings,namely cosemiprime ringas a generalization of semiprime ring,where a ring C is said to be cosemiprime ring if I= for each ideal I of C .Some properties of this type of rings are obtained . Also,we determin the relationship among types of ideals in this ring.


Environmental And Diagnostic Study Of Some Parasites In River Diwaniyah-Fish Of Al Xanthopterus, Abtisam Jasim Abbas Jan 2023

Environmental And Diagnostic Study Of Some Parasites In River Diwaniyah-Fish Of Al Xanthopterus, Abtisam Jasim Abbas

Al-Qadisiyah Journal of Pure Science

The current study was concerned with investigating parasitic infections in Barbus Xanthopterus fish in Al-Diwaniyah River, for the period (July 2020-December 2020). (218) fish were collected from three different locations along the Al-Diwaniyah River. The results of the laboratory examination indicated that the fish were infected with the parasite Chilodonella Cyprinid and Eimiria sinenis. The current study recorded changes in the physical and chemical properties of Al-Diwaniyah River water, as the water temperature values, measured turbidity values, pH, electrical conductivity, hardness and TDS recorded a clear variation during the months of the study. The results of the statistical analysis indicated …