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Full-Text Articles in Chemistry

Analysis Of Genetic Engineering Material Misconceptions In Biology Textbooks For Ninth-Grade In Yogyakarta, Silfi Pratiwi, Purwanti Pratiwi Purbosari, Oktira Roka Aji, Rinaldi Rizal Putra Jun 2024

Analysis Of Genetic Engineering Material Misconceptions In Biology Textbooks For Ninth-Grade In Yogyakarta, Silfi Pratiwi, Purwanti Pratiwi Purbosari, Oktira Roka Aji, Rinaldi Rizal Putra

Jurnal Pendidikan Sains

Textbooks play a pivotal role in the pedagogical landscape, serving as indispensable aids for learning, founts of knowledge, and platforms for practical application. This study endeavors to scrutinize the content of textbooks, specifically focusing on ninth-grade biology textbooks within the educational milieu of Yogyakarta City, and to juxtapose these contents with existing literature to discern potential misconceptions. Employing a descriptive qualitative approach, the investigation centers on printed biology textbooks utilized in ninth-grade curricula across junior high schools in Yogyakarta. The selection of textbooks for analysis was based on their prevalence as instructional materials, as determined through survey data. Genetic engineering …


Problem-Based Learning Model Assisted With A Humanistic-Merdeka Belajar Approach Improved Biology Students’ Learning Ownership, Dita Tri Mulyani, Dwi Listyorini Jun 2024

Problem-Based Learning Model Assisted With A Humanistic-Merdeka Belajar Approach Improved Biology Students’ Learning Ownership, Dita Tri Mulyani, Dwi Listyorini

Jurnal Pendidikan Sains

Fostering ownership over learning constitutes a pivotal aspect for students to cultivate a comprehensive understanding, employ cognitive strategies effectively, hone essential skills, and refine learning methodologies. Preliminary studies have underscored a prevalent deficiency in the learning ownership among biology students, categorizing it as notably low. The purpose of this study is to ascertain the effect of the Project Based Learning (PBL) model assisted with a Humanistic-Merdeka Belajar (HMB) approach, in nurturing students’ ownership of their learning endeavors. Employing a quasi-experimental design, the research adopts a pre-test post-test non-equivalent control group configuration, administered both prior to and following the intervention within …


Asistensi Mengajar (Am) Program In Merdeka Belajar Kampus Merdeka (Mbkm) As A Pedagogical Mastery Accelerator For Vocational High School Teacher Candidates, Muhammad Idris Effendi, Yoto Yoto, Widiyanti Widiyanti Jun 2024

Asistensi Mengajar (Am) Program In Merdeka Belajar Kampus Merdeka (Mbkm) As A Pedagogical Mastery Accelerator For Vocational High School Teacher Candidates, Muhammad Idris Effendi, Yoto Yoto, Widiyanti Widiyanti

Jurnal Pendidikan Sains

This research delves into the issue of inadequate pedagogical proficiency among vocational high school (SMK) teacher candidates, primarily stemming from the constrained timeframe of educational internships, typically spanning a mere two months. As an option, this study suggests the implementation of an Asistensi Mengajar (AM) initiative within the framework of the Merdeka Belajar Kampus Merdeka Program (MBKM), extending over a semester’s duration. Employing a literature review methodology, the research highlights that the brevity of conventional two-month internships poses a significant impediment to the development of pedagogical acumen among SMK teacher candidates. The proposed option entails an AM program under MBKM, …


Identify Resources Activated By Students When Solving Straight Motion Kinematics Problems With Different Representation, Nur Utami Amaliah, Sutopo Sutopo, Eny Latifah, Hutkemri Zulnaidi Jun 2024

Identify Resources Activated By Students When Solving Straight Motion Kinematics Problems With Different Representation, Nur Utami Amaliah, Sutopo Sutopo, Eny Latifah, Hutkemri Zulnaidi

Jurnal Pendidikan Sains

This research aims to explore kinematic resources in linear kinematics by utilizing different forms of problem representation. The study was conducted by administering 15 reasoned multiple-choice questions to 146 high school students from three districts in Central Sulawesi, Indonesia. The research instrument covers topics in linear kinematics, including distance, displacement, speed, and velocity, presented through diagrammatic representations, graphs, and mathematical equations. The students’ written answers were analyzed both quantitatively and qualitatively. Quantitative analysis was conducted to determine descriptive statistics from the data, while qualitative analysis identified the resources students activated when solving these questions. The findings reveal that the various …


Effects Of The Biochar Of Senna Tora On The Soil Fertility Of Misau Farmlands, Bauchi State, Northern Nigeria, Ozoilo Onyeka Calistus, Umar Faruk Hassan, Auwal Adamu Mahmoud, Haruna Baba, Hamza Badamasi, Hannatu Akanang Jun 2024

Effects Of The Biochar Of Senna Tora On The Soil Fertility Of Misau Farmlands, Bauchi State, Northern Nigeria, Ozoilo Onyeka Calistus, Umar Faruk Hassan, Auwal Adamu Mahmoud, Haruna Baba, Hamza Badamasi, Hannatu Akanang

Journal of Bioresource Management

The use of biochar as an amendment to the soil is attracting the scientific community's attention because of its cost-effectiveness, eco-friendliness, and its promising success in increasing the fertility of the soil and crop yield. In the present study, the effects of biochar from Senna tora applications on soil characteristics and the availability of micronutrients in Misau, Bauchi State, Nigeria, were explored. A completely randomized approach was adopted and duplicated three times, with reference soil (no biochar), 30-day, and 60-day biochar treatments. The biochar was removed at the end of the treatment, and soil samples from the various treatments were …


Pseudo-Siamese Network Combined With Label-Free Raman Spectroscopy For The Quantification Of Mixed Trace Amounts Of Antibiotics In Human Milk: A Feasibility Study, Jing Yi Mou, Muhammad Usman, Jia Wei Tang, Quan Yuan, Zhang Wen Ma, Xin Ru Wen, Zhao Liu, Liang Wang Jun 2024

Pseudo-Siamese Network Combined With Label-Free Raman Spectroscopy For The Quantification Of Mixed Trace Amounts Of Antibiotics In Human Milk: A Feasibility Study, Jing Yi Mou, Muhammad Usman, Jia Wei Tang, Quan Yuan, Zhang Wen Ma, Xin Ru Wen, Zhao Liu, Liang Wang

Research outputs 2022 to 2026

The utilization of antibiotics is prevalent among lactating mothers. Hence, the rapid determination of trace amounts of antibiotics in human milk is crucial for ensuring the healthy development of infants. In this study, we constructed a human milk system containing residual doxycycline (DXC) and/or tetracycline (TC). Machine learning models and clustering algorithms were applied to classify and predict deficient concentrations of single and mixed antibiotics via label-free SERS spectra. The experimental results demonstrate that the CNN model has a recognition accuracy of 98.85% across optimal hyperparameter combinations. Furthermore, we employed Independent Component Analysis (ICA) and the pseudo-Siamese Convolutional Neural Network …


Discovering Potential In Non-Cancer Medications: A Promising Breakthrough For Multiple Myeloma Patients., Omar S Al-Odat, Emily Nelson, Tulin Budak-Alpdogan, Subash C. Jonnalagadda, Dhimant Desai, Manoj K Pandey Jun 2024

Discovering Potential In Non-Cancer Medications: A Promising Breakthrough For Multiple Myeloma Patients., Omar S Al-Odat, Emily Nelson, Tulin Budak-Alpdogan, Subash C. Jonnalagadda, Dhimant Desai, Manoj K Pandey

College of Science & Mathematics Departmental Research

Multiple myeloma (MM) is a common type of cancer that unfortunately leads to a significant number of deaths each year. The majority of the reported MM cases are detected in the advanced stages, posing significant challenges for treatment. Additionally, all MM patients eventually develop resistance or experience relapse; therefore, advances in treatment are needed. However, developing new anti-cancer drugs, especially for MM, requires significant financial investment and a lengthy development process. The study of drug repurposing involves exploring the potential of existing drugs for new therapeutic uses. This can significantly reduce both time and costs, which are typically a major …


Study Of Modified Salinomycin Analogs On Inhibition Of Triple Negative Breast Cancer Metastasis And Invasion, Farnaz Malekmarzban Jun 2024

Study Of Modified Salinomycin Analogs On Inhibition Of Triple Negative Breast Cancer Metastasis And Invasion, Farnaz Malekmarzban

Theses and Dissertations

Triple negative breast cancer (TNBC) is a more aggressive type of breast cancer which contains faster growth, higher metastasis rate and worse prognosis. The main challenge toward treatment of this type of cancer is being heterogeneous. Recently, Salinomycin (SAL) has been considered as a potential agent for triple negative breast cancer treatment. However, chemical modification of SAL is needed to improve SAL selectivity to cations and decrease its cytotoxicity. The purpose of this study was to evaluate the effect of chemically modified analogs of SAL on the viability, metastasis, Wnt pathway as well as angiogenesis of Triple negative breast cancer …


Harnessing Redox Polymer Dynamics For Enhanced Glucose-Oxygen Coupling In Dual Biosensing And Therapeutic Applications, Wassim El Housseini, Egor Baiarashov, Rokas Gerulskis, Adam Milam, Shelley D. Minteer Jun 2024

Harnessing Redox Polymer Dynamics For Enhanced Glucose-Oxygen Coupling In Dual Biosensing And Therapeutic Applications, Wassim El Housseini, Egor Baiarashov, Rokas Gerulskis, Adam Milam, Shelley D. Minteer

Chemistry Faculty Research & Creative Works

The burgeoning field of continuous glucose monitoring (CGM) for diabetes management faces significant challenges, particularly in achieving precise and stable biosensor performance under changing environmental conditions such as varying glucose concentrations and O2 levels. To address this, we present a novel biosensor based on the electroless coupling of glucose oxidation catalyzed by flavin-dependent glucose dehydrogenase (FAD-GDH) and O2 reduction catalyzed by bilirubin oxidase (BOD) via a redox polymer, dimethylferrocene-modified linear poly(ethylenimine), FcMe2-LPEI. Initial cyclic voltammetry tests confirm the colocalization of both enzymatic reactions within the potential range of the polymer, indicating an effective electron shuttle mechanism. …


Surface Structures And Properties Of High-Voltage Licoo2: Reviews And Prospects, Jian-Jun Fang, Yu-Hao Du, Zi-Jian Li, Wen-Guang Fan, Heng-Yu Ren, Hao-Cong Yi, Qing-He Zhao, Feng Pan Jun 2024

Surface Structures And Properties Of High-Voltage Licoo2: Reviews And Prospects, Jian-Jun Fang, Yu-Hao Du, Zi-Jian Li, Wen-Guang Fan, Heng-Yu Ren, Hao-Cong Yi, Qing-He Zhao, Feng Pan

Journal of Electrochemistry

Nowadays, the development of high-voltage LiCoO2 (lithium cobalt oxide, LCO) cathodes has attracted the widespread attention from both the academic and industry fields. Among the multiple concerns, researches on the surface issues would provide the most effective performance optimization pathway for the synthesis of high-voltage LCO. In this work, the issues of high-voltage LCO, including the phase transitions and crack formation, the oxygen redox related issues and side reactions, as well as the surface structure degradation, have been systematically reviewed. Then, we further clarify the surface modulations, and the interplay between the surface modulation and electrolyte tuning. Finally, we …


In Situ Diffuse Reflectance Spectroelectrochemistry Of Cathode Materials In Lithium-Ion Batteries, Lu-Lu Chen, Hao-Ran Li, Wei-Yi Liu, Wei Wang Jun 2024

In Situ Diffuse Reflectance Spectroelectrochemistry Of Cathode Materials In Lithium-Ion Batteries, Lu-Lu Chen, Hao-Ran Li, Wei-Yi Liu, Wei Wang

Journal of Electrochemistry

Developing in situ spectroelectrochemistry methods, which can provide detailed information about species transformation during electrochemical reactions, is very important for studying electrode reaction mechanisms and improving battery performance. Studying real-time changes in the surface of electrode materials during normal operation can be an effective way to assess and optimize the practical performance of electrode materials, thus, in situ and in operando characterization techniques are particularly important. However, batteries are hard to be studied by in situ characterization measurements due to their hermetically sealed shells, and there is still much room for battery characterizations. In this work, a specially designed battery …


Molybdenum Disulfide And Carbon Nanotubes Composite Electrode For Electrochemical Conversion Of Salinity Gradient Energy, Jia-Jun Li, Wei-Bin Zhang, Xin-Yu Liu, Jing-Lei Yang, Yi Yin, Ze-Qin Yang, Xue-Jing Ma Jun 2024

Molybdenum Disulfide And Carbon Nanotubes Composite Electrode For Electrochemical Conversion Of Salinity Gradient Energy, Jia-Jun Li, Wei-Bin Zhang, Xin-Yu Liu, Jing-Lei Yang, Yi Yin, Ze-Qin Yang, Xue-Jing Ma

Journal of Electrochemistry

The ocean accounts for 97% of the total water resources on earth, covering over 70% of the map's surface area. With the continuous consumption of non-renewable energy sources such as fossil fuels and the rapid development of renewable energy, humans are increasingly paying attention to the utilization of ocean resources. Ocean energy includes tidal energy, wave energy, temperature difference energy, and salinity gradient energy. Salinity gradient energy is the energy generated by the interaction of seawater and fresh water, which is the ocean energy existing in the form of chemical energy. This energy is mostly generated in estuaries. The osmotic …


The Discovery Of First Ret Protac With In Vivo Activity, Yafeng Wang Jun 2024

The Discovery Of First Ret Protac With In Vivo Activity, Yafeng Wang

USF Tampa Graduate Theses and Dissertations

This report mainly discusses the development of RET Proteolysis targeting chimera PROTAC molecules based on Selpercatinib (LOXO-292) and Sulfono-γ-AApeptide PROTAC. A PROTAC molecule is a bifunctional molecule composed of two active domains and a linker. It works by inducing selective protein intracellular degradation. This technology was first discussed by Kathleen Sakamoto, Ray Deshaies and Craig Crews in 2001. Using various E3 Ligase, such as CRBN, pVHL, beta-TrCP1, Mdm2, DCAF15, DCAF16, RNF114, and c-IAP1, the PROTAC technology has been applied to several novel drug development,. Yale University licensed the PROTAC technology to Arvinas in 2013–14. For my research, Chapter one summarizes …


Electrochemical Detection Of Glucose Using A Prussian Blue Modified Electrodes Combined With Glucose Encapsulated Within A Xerogel, Daniel Baker, Sarah Davis, Drew Budner Jun 2024

Electrochemical Detection Of Glucose Using A Prussian Blue Modified Electrodes Combined With Glucose Encapsulated Within A Xerogel, Daniel Baker, Sarah Davis, Drew Budner

Journal of the South Carolina Academy of Science

Recent literature reports examples of electrochemical biosensor systems that have been developed based upon on the encapsulation of enzymes and metal nanoparticles into a xerogel. These systems have been utilized for the detection of biologically important compounds, such as glucose. These reports on these systems have found acceptable detection limits and linear ranges. At the same time, Prussian blue modified electrodes have been shown to have better operating parameters than metal electrodes for the detection of hydrogen peroxide. In this work, a biosensor system is described that incorporates the encapsulation of glucose oxidize within a xerogel combined with electrochemical detection …


The Asymmetric Total Synthesis Of Membranolide And Efforts Towards The Oxeatamides, Sean Bradley Jun 2024

The Asymmetric Total Synthesis Of Membranolide And Efforts Towards The Oxeatamides, Sean Bradley

USF Tampa Graduate Theses and Dissertations

Total synthesis is a discipline within organic chemistry that is a constant force that propels the field forward. In our lab, we have immersed ourselves within the field of total synthesis to gain access to complex natural products, perform SAR studies, as well as highlight interesting methodology. Within these endeavors, we have completed the first asymmetric synthesis of membranolide. This has allowed us to explore potential biofilm eradication in our efforts to develop novel therapeutics to combat the ESKAPE pathogens and multi-drug resistance. We have also begun to pursue the first asymmetric total synthesis of the oxeatamides. By utilizing our …


Microencapsulation Of Cosmos Caudatus Kunth Extract Using Sodium Alginate And In Vitro Antioxidant Activity Test, Safina Samara Nur Fadlila, Oktavia Eka Puspita, Zubaidah Ningsih, Anna Safitri Jun 2024

Microencapsulation Of Cosmos Caudatus Kunth Extract Using Sodium Alginate And In Vitro Antioxidant Activity Test, Safina Samara Nur Fadlila, Oktavia Eka Puspita, Zubaidah Ningsih, Anna Safitri

Makara Journal of Science

This study aims to encapsulate Cosmos caudatus K. leaf extract in sodium alginate crosslinked with calcium chloride (CaCl2) as coating materials through freeze-drying. Antioxidant assays were performed to evaluate the applicability of the microcapsules as antidiabetic medicines. Their characteristics, antioxidant activity, and encapsulation efficiency (EE) were also examined. Results indicated that the concentration of sodium alginate and pH influenced the manufacturing process of the microcapsules. The highest EE was obtained at pH 6 and alginate concentration of 2% (w/v). The IC50 for the antioxidant activity of the microcapsules was 139.96 ± 1.094 μg/mL. Scanning electron microscopy confirmed …


Vibrational Dynamics Of The Intramolecular H-Bond In Β-Diketones And Intermolecular H Bonding In Halide-Receptor Complexes Investigated With Transient And 2d Ir Spectroscopy, Jessika Lira-Santos Dean Jun 2024

Vibrational Dynamics Of The Intramolecular H-Bond In Β-Diketones And Intermolecular H Bonding In Halide-Receptor Complexes Investigated With Transient And 2d Ir Spectroscopy, Jessika Lira-Santos Dean

Arts & Sciences Graduate Student Theses and Dissertations

Hydrogen bonding (H-bond) interactions are essential in dictating structures and properties of chemical and biological systems and are pivotal mediators in charge transport reactions and chemical recognition. Accurate description of H-bonds requires thorough characterization of the shared proton’s potential energy surface (PES) and molecular dynamics. Ultrafast nonlinear spectroscopic techniques, in particular, transient absorption (TA) and two dimensional infrared (2D IR) spectroscopy, have proven themselves valuable tools for probing molecular structures and dynamics mediated by H-bonding interactions. Herein, I describe the implementation of TA and 2D IR experiments to investigate the vibrational dynamics of the intramolecular H-bond in a series of …


Interpenetrated Lattices Of Quaternary Chalcogenides Displaying Magnetic Frustration, High Na-Ion Conductivity, And Cation Redox In Na-Ion Batteries, Santhoshkumar Sundaramoorthy, Srikanth Balijapelly, Sudip Mohapatra, Sutapa Bhattacharya, Kartik Ghosh, Amitava Choudhury Jun 2024

Interpenetrated Lattices Of Quaternary Chalcogenides Displaying Magnetic Frustration, High Na-Ion Conductivity, And Cation Redox In Na-Ion Batteries, Santhoshkumar Sundaramoorthy, Srikanth Balijapelly, Sudip Mohapatra, Sutapa Bhattacharya, Kartik Ghosh, Amitava Choudhury

Chemistry Faculty Research & Creative Works

A series of quaternary selenides, NaxMGaSe4 (M = Mn, Fe, and mixed Zn/Fe), have been synthesized for the first time employing a high-temperature solid-state synthesis route through stochiometric or polychalcogenide flux reactions. Along with the selenides, a previously reported sulfide analogue, NaxFeGaS4, is also revisited with new findings. These compounds form an interpenetrated structure made up of a supertetrahedral unit. The electrochemical evaluations exhibit a reversible (de)intercalation of ∼0.6 and ∼0.45 Na-ions, respectively, from Na2.87FeGaS4 (1a) and Na2.5FeGaSe4 (2) involving Fe2+/Fe3+ redox when cycled between 1.5 and 2.5 …


Mechanistic Rationale For Ketene Formation During Dabbing And Vaping, Kaelas R. Munger, Killian M. Anreise, Robert P. Jensen, David H. Peyton, Robert M. Strongin Jun 2024

Mechanistic Rationale For Ketene Formation During Dabbing And Vaping, Kaelas R. Munger, Killian M. Anreise, Robert P. Jensen, David H. Peyton, Robert M. Strongin

Chemistry Faculty Publications and Presentations

Ketene is one of the most toxic vaping emissions identified to date. However, its high reactivity renders it relatively challenging to identify. In addition, certain theoretical studies have shown that realistic vaping temperature settings may betoo low to produce ketene. Each of these issues is addressed herein. First, an isotopically labeled acetate precursor is used for the identification of ketene with enhanced rigor in vaped aerosols. Second, discrepancies between theoretical and experimental findings are explained by accounting for the effects of aerobic (experimental) versus anaerobic (simulated and theoretical) pyrolysis conditions. This finding is also relevant to explaining the relatively low-temperature …


Designing Dual-Responsive Drug Delivery Systems: The Role Of Phase Change Materials And Metal-Organic Frameworks., Wanying Wei, Ping Lu Jun 2024

Designing Dual-Responsive Drug Delivery Systems: The Role Of Phase Change Materials And Metal-Organic Frameworks., Wanying Wei, Ping Lu

College of Science & Mathematics Departmental Research

Stimuli-responsive drug delivery systems (DDSs) offer precise control over drug release, enhancing therapeutic efficacy and minimizing side effects. This review focuses on DDSs that leverage the unique capabilities of phase change materials (PCMs) and metal-organic frameworks (MOFs) to achieve controlled drug release in response to pH and temperature changes. Specifically, this review highlights the use of a combination of lauric and stearic acids as PCMs that melt slightly above body temperature, providing a thermally responsive mechanism for drug release. Additionally, this review delves into the properties of zeolitic imidazolate framework-8 (ZIF-8), a stable MOF under physiological conditions that decomposes in …


Targeting Persistence: Improving Success Of Stem Students, Teresa J. Bixby, Alec Werner Jun 2024

Targeting Persistence: Improving Success Of Stem Students, Teresa J. Bixby, Alec Werner

Chemistry Department Faculty Conferences

Half of STEM majors leave their program without earning a degree. Many of those who leave do so within their first two years of study. A series of exploratory investigations of the mindset, identity, and sense of community of undergraduate students were completed. Differences in mindset were found between underclassmen and upperclassmen, where upperclassmen tended towards growth mindset traits and often described undergoing a shift from fixed to growth mindset during their undergraduate career. Participation in undergraduate research was found to be a driving factor of persistence with numerous benefits, most significantly STEM identity development and sense of community.


Potent And Selective Small Molecule Mcl-1 Inhibitor Demonstrates Anti-Myeloma Activity And Overcomes Chemotherapy Resistance, Omar Sami Faleh Al-Odat Jun 2024

Potent And Selective Small Molecule Mcl-1 Inhibitor Demonstrates Anti-Myeloma Activity And Overcomes Chemotherapy Resistance, Omar Sami Faleh Al-Odat

Theses and Dissertations

Despite a record number of clinical studies investigating various anti-myeloma treatments, the 5-year survival rate for multiple myeloma (MM) patients in the US is only 55%, and nearly all patients relapse. Poor patient outcomes demonstrate that myeloma cells are "born to survive” which means they can adapt and evolve following treatment. Thus, new therapeutic approaches to combat survival mechanisms and target treatment resistance are required. Importantly, Mcl-1, anti-apoptotic protein, is required for the development of MM and treatment resistance. This study looks at the possibility of KS18, a selective Mcl-1 inhibitor, to treat MM and overcome resistance. Our investigation demonstrates …


Analysis On Development Trend Of Global Hypersonic Technology, Xiaorong Huang, Yunwei Chen, Haichen Zhou Jun 2024

Analysis On Development Trend Of Global Hypersonic Technology, Xiaorong Huang, Yunwei Chen, Haichen Zhou

Bulletin of Chinese Academy of Sciences (Chinese Version)

Hypersonic technology is a key technology in the aerospace field in the future and is of very important strategic and forward-looking significance. Using bibliometric methods, it is found that research on hypersonic technology is mainly concentrated in the military field, among which power propulsion technology, navigation guidance and control technology, thermal protection technology and new materials are important research directions in this field. After sorting out the research and development situation of various countries, it is found that the relevant core technologies related to the development of hypersonic weapons are still the focus of future research. At the same time, …


Implementing 1.5 Millimeter Internal Diameter Columns And A Portable Capillary Column Instrument Into Monoclonal Antibody Analytical Workflows, Benjamin Libert Jun 2024

Implementing 1.5 Millimeter Internal Diameter Columns And A Portable Capillary Column Instrument Into Monoclonal Antibody Analytical Workflows, Benjamin Libert

Theses and Dissertations

Using 1.5 mm inner diameter (i.d.) columns to bridge the gap between routinely used 2.1 mm i.d. columns and capillary bore columns allows for a sequential but significant increase in performance without the need for specialized equipment associated with very low dispersion liquid chromatography (LC) systems. These 1.5 mm i.d. columns balance an increase in sensitivity compared to 2.1 mm i.d. columns (theoretically doubling the time-domain peak area in mass sensitive detectors for the same mass load), while mitigating the efficiency losses due to extra-column dispersion effects that are commonly observed with 1.0 mm i.d. columns. Here, the use of …


Thermal Effects On The Voc-Sensitive Polydimethylsiloxane Holographic Gratings, Aleksandra Hernik, Faolan Radford Mcgovern, Patrick Iftime, Izabela Naydenova Jun 2024

Thermal Effects On The Voc-Sensitive Polydimethylsiloxane Holographic Gratings, Aleksandra Hernik, Faolan Radford Mcgovern, Patrick Iftime, Izabela Naydenova

Conference Papers

The imperative for monitoring volatile organic compounds (VOCs) emerges from their harmful impact on human health when inhaled excessively over a long term. Polydimethylsiloxane (PDMS), valued for its transparency and excellent flexibility, has already been demonstrated as a promising biocompatible and cost-effective transducer for optical VOCs sensing. Moreover, it facilitates further functionalisation with adsorbing materials to enhance sensitivity and selectivity for specific VOCs detection. We fabricated and examined PDMS-based surface diffraction gratings after exposure to selected VOCs, demonstrating different response for polar and non-polar molecules. Investigated gratings were prepared by replicating sinusoidal surface relief structures inscribed in acrylamide photopolymer using …


The Glucosylamine Oxidation Pathway Of Vitamin C Recycling, James M. Hempe, Daniel S. Hsia, Arthur Hagar, Larry Byers Jun 2024

The Glucosylamine Oxidation Pathway Of Vitamin C Recycling, James M. Hempe, Daniel S. Hsia, Arthur Hagar, Larry Byers

School of Medicine Faculty Publications

The proposed glucosylamine oxidation pathway (GOP) is a two-step, intraerythrocyte, thermodynamically favorable nonenzymatic reaction that first binds glucose to the N-terminal valine of beta globin (βVal1) to form a closed-chain glucosylamine that can spontaneously reduce oxidized vitamin C to its antioxidant form. This review summarizes analytical, biochemical and clinical research supporting the existence of the GOP and the surprising hypothesis that βVal1 glucosylamine is a reducing agent that works cooperatively with reduced glutathione to dynamically regulate vitamin C recycling during naturally occurring periods of transiently or chronically elevated blood glucose and oxidant production. Rationale for the existence of the GOP …


Synthetic Assembly Of Antibacterial Agents And Metal Chelating Ligands, Zachary Joseph Liveris Jun 2024

Synthetic Assembly Of Antibacterial Agents And Metal Chelating Ligands, Zachary Joseph Liveris

Dissertations

The exploitation of chemical synthesis exemplifies the notion of bridging both innovation and curiosity for the strategic assembly of sophisticated molecular infrastructures. By exerting this continuously evolving and versatile tool, synthesis has been applied in the development and influence of a myriad of ligands, biological probes, and persists to direct pharmaceutical innovation and modern medicine alike. Since pathogenic multidrug-resistant (MDR) microbial strains remain to be a persistent threat to both clinical healthcare and society, the need to develop selective and efficacious antibacterial agents that can impede microbe pathogenicity and regulate cellular mortality is paramount. In contrast to pharmaceutical development, organic …


Turning Trash Into Treasure: Using Old Optical Spectrometers As Learning Tools In Instrumental Analysis, Ken Overway Jun 2024

Turning Trash Into Treasure: Using Old Optical Spectrometers As Learning Tools In Instrumental Analysis, Ken Overway

Chemistry Faculty Scholarship

Chemical instrumentation is complex and expensive. When an instrument becomes nonfunctional, its pedagogical value remains despite its inability to make measurements. This work presents a laboratory experiment which gives new purpose to old optical spectrometers while building knowledge and confidence of students in their understanding of chemical instrumentation. Students are given a guided tour of spectroscopic instruments, starting from the simplest, and are asked to identify components and draw the optical path of each instrument. Allowing students to look inside of decommissioned instruments gives students a chance to see the differences and similarities of optical spectrometers while reinforcing the form …


Investigation Of The Uv-Resistance Of Photopolymerisable Glass For Space Applications, Luca Sorridente, Tatsiana Mikulchyk, Izabela Naydenova, Kevin Murphy Jun 2024

Investigation Of The Uv-Resistance Of Photopolymerisable Glass For Space Applications, Luca Sorridente, Tatsiana Mikulchyk, Izabela Naydenova, Kevin Murphy

Articles

The progress of space based scientific research leads to an increasing demand for more efficient and less bulky instruments. Conventional refractive elements make up a critical part of many optical instruments launched into space; however, they can be bulky and heavy. Holographic optical elements are an efficient alternative to replace the conventional optical elements as they are lightweight and can be miniaturized. Current materials typically used for volume holographic optical elements are not robust enough for use in space environment. Recently a promising photopolymerisable glass has been developed using a sol-gel technique, which can provide dry layers suitable for holographic …


Photopolymer Material Durability And Safety In Holographic Diffusers For Visual Applications, Matthew Hellis, Alan Casey, Edoardo Splendi, Suzanne Martin, Matthew Sheehan, Kevin Murphy Jun 2024

Photopolymer Material Durability And Safety In Holographic Diffusers For Visual Applications, Matthew Hellis, Alan Casey, Edoardo Splendi, Suzanne Martin, Matthew Sheehan, Kevin Murphy

Articles

This study introduces novel holographic diffuser applications employing acrylamide- or diacetone acrylamide-based photopolymers, patterned within the volume on a micron scale by a single-beam holographic recording process. These diffusers have previously been presented as potential treatments for amblyopia and diplopia. This work has now been extended to spectrometric analysis to determine their properties under broadband light. Diffusive elements with higher diffusion efficiencies exhibited a marginal reduction (< 5%) in diffusion efficiency across most of the visible spectrum. Given the intended application of these holographic diffusers, cytotoxicity assessments were also performed. This is significant as there is a difference in toxicity between the crystalline acrylamide (classified as a category 3 material) and diacetone acrylamide (classified as a category 4 material). The findings indicated substantially lower toxicity in holograms produced with diacetone acrylamide-based photopolymer. The accelerated ageing of both formulations of holographic diffusers indicated that the acrylamide-based holographic diffusers did not reduce efficacy in the 292 days of ageing. The diacetone acrylamide-based holographic diffusers exhibited reduced efficacy by day 182. Despite this, both formulations have been shown to perform for prolonged periods as the treatment modality would require. These results emphasise that holographic diffusers exhibit minimal spectral impact, and longevity on the scale of treatment regimes which are crucial considerations for their prospective use case as treatments for amblyopia and diplopia.