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Articles 2131 - 2160 of 3949

Full-Text Articles in Chemistry

A Kinetic Study Of Regulation Of Glua1 Homomeric And Heteromeric Ampa Receptors By 2,3-Benzodiazepines, Yin-Shuo (Andrew) Wu Jan 2017

A Kinetic Study Of Regulation Of Glua1 Homomeric And Heteromeric Ampa Receptors By 2,3-Benzodiazepines, Yin-Shuo (Andrew) Wu

Legacy Theses & Dissertations (2009 - 2024)

AMPA receptors are a subtype of the ionotropic glutamate receptor family. They are ligand-gated or glutamate-activated, transmembrane ion channels that mediate the majority of excitatory synaptic transmission in the central nervous system. AMPA receptors are essential for neuronal development and brain functions, including learning and memory. Over-activation of calcium permeable AMPA receptors has been linked to some neurological diseases such as stroke, Alzheimer’s disease and amyotrophic lateral sclerosis. Inhibitors of glutamate receptors are therefore drug candidates for the potential treatment of these neurological diseases. One of the most promising classes of AMPA receptor antagonists is 2,3-benzodiazepine derivatives, thought to be …


Investigating The Role Of Epitranscriptomics In Viral Immunity, Kaycie S. Lawson Jan 2017

Investigating The Role Of Epitranscriptomics In Viral Immunity, Kaycie S. Lawson

Legacy Theses & Dissertations (2009 - 2024)

The characterization of host-virus relationships is essential for understanding the process of viral replication and driving the development of effective viral targeting strategies. In this work, I tested the hypothesis that ribonucleic acid (RNA) post-transcriptional modifications (PTMs) may play a significant role in defining host-virus interactions. The model system consisted of a yeast strain capable of harboring the endogenous L-A virus, which allowed me to evaluate the possible involvement of PTMs in the process of cellular immunity to virus-borne toxicity. A mass spectrometry-based platform was utilized to compare the global PTM profile of wild-type yeast with those of the same …


Further Development Of Raman Spectroscopy For Body Fluid Investigation : Forensic Identification, Limit Of Detection, And Donor Characterization, Claire K. Muro Jan 2017

Further Development Of Raman Spectroscopy For Body Fluid Investigation : Forensic Identification, Limit Of Detection, And Donor Characterization, Claire K. Muro

Legacy Theses & Dissertations (2009 - 2024)

The challenges to forensic body fluid analysis have placed limitations on the type of information that investigators can acquire and how that information can be collected. In recent years, Raman spectroscopy has proven itself useful for characterizing body fluids. In 2008, a large-scale investigation was undertaken to explore the use of Raman spectroscopy as a means of identifying body fluids. This work resulted in multidimensional Raman spectroscopic signatures for the five main body fluids: semen, peripheral blood, saliva, vaginal fluid, and sweat. These studies were incredibly successful and created the foundation for years of continued research. Accordingly, the studies included …


Structural Characterization Of The Interactions Of Nicotinamide And Analogs With Human Sirt6 By Saturation Transfer Difference (Std) Nmr And Site Directed Mutagenesis, Beatriz Elena Bolivar-Vega Jan 2017

Structural Characterization Of The Interactions Of Nicotinamide And Analogs With Human Sirt6 By Saturation Transfer Difference (Std) Nmr And Site Directed Mutagenesis, Beatriz Elena Bolivar-Vega

Legacy Theses & Dissertations (2009 - 2024)

The allosteric regulation of SIRT6 by nicotinamide (NAM), along with the growing evidence of this enzyme's key role in the immune response, prompted the mechanistic study of SIRT6 inhibition by pyrazinamide (PZA) and analogs. In our current study, PZA, an analog of NAM, was revealed to have a modest modulatory effect on SIRT6, an enzyme that regulates the NF-κB signaling pathway at the transcriptional level (a relevant pathway to inflammation). Similarly, the analogs of PZA, 5-Cl PZA, 5-MeO PZA, and POA exhibited a modulatory effect against SIRT6 in our in vitro studies, enabling identification of a potential new target for …


Differential Activation Of Dead Box Rna Helicases Rhlb And Rhle By Hfq/Srnas And Their Target Mrnas, Amit Kumar Jan 2017

Differential Activation Of Dead Box Rna Helicases Rhlb And Rhle By Hfq/Srnas And Their Target Mrnas, Amit Kumar

Wayne State University Theses

Number of small RNA (sRNA) gene regulators have mounted in E. coli over the years whereas the number of validated protein partners has not changed considerably. Hfq has remained the only well studied global regulatory partner of sRNAs in E. coli. However, direct or indirect involvement of other protein partners has always been speculated. Study from Blasi lab has shown that CsdA, one of the five DEAD-box RNA helicases of E. coli, is required for the DsrA mediated upregulation of rpoS under cold stress condition. Previous study from our lab has identified two other DEAD-box RNA helicases, RhlB and RhlE, …


Design, Synthesis And Analysis Of Potential Photo-Activatable Cathepsin K Inhibitors, Khalin Evania Nisbett Jan 2017

Design, Synthesis And Analysis Of Potential Photo-Activatable Cathepsin K Inhibitors, Khalin Evania Nisbett

Wayne State University Theses

Abstract

DESIGN, SYNTHESIS AND ANALYSIS OF POTENTIAL PHOTO-ACTIVATABLE CATHEPSIN K INHIBITORS

by

KHALIN NISBETT

May 2017

Advisor: Dr. Jeremy Kodanko

Major: Chemistry

Degree: Master of Science

Tightly regulated cysteine CA proteases play a major role in maintaining the homeostasis within cells. Subsequently, when these proteases are dysregulated and mislocalized they disrupt healthy cell dynamics and contribute to many life-threatening pathologies such arteriosclerosis, osteoporosis and cancer. As such many pharmaceutical companies and research teams are highly interested in these proteases as targets. One emergent strategy is the spatiotemporal control of biological processes. In relation to this, a series of spatiotemporally controlled …


Using Low-Coherence Interferometry To Monitor Cell Invasion In An In-Vitro Model System, Behnaz Davoudi Nasab Jan 2017

Using Low-Coherence Interferometry To Monitor Cell Invasion In An In-Vitro Model System, Behnaz Davoudi Nasab

Honors Undergraduate Theses

In an optically random system, such as naturally occurring and man-made media, light undergoes pronounced multiple scattering. This phenomenon has shown a remarkable potential in characterizing complex materials. In this regime, scattering occurs from each individual center of the scattering and independent scattering events lead to multiple light scattering. This phenomenon is often described as a random walk of photons and can be modeled in terms of a diffusion equation based on the radiative transfer theory. In this thesis, we used optical path-length spectroscopy (OPS), which is an experimental method to obtain the path-length probability density of the propagating light …


Micro-Spectroscopy Of Bio-Assemblies At The Single Cell Level, Jeslin Kera Jan 2017

Micro-Spectroscopy Of Bio-Assemblies At The Single Cell Level, Jeslin Kera

Honors Undergraduate Theses

In this thesis, we investigate biological molecules on a micron scale in the ultraviolet spectral region through the non-destructive confocal absorption microscopy. The setup involves a combination of confocal microscope with a UV light excitation beam to measure the optical absorption spectra with spatial resolution of 1.4 μm in the lateral and 3.6 μm in the axial direction. Confocal absorption microscopy has the benefits of requiring no labels and only low light intensity for excitation while providing a strong signal from the contrast generated by the attenuation of propagating light due to absorption. This enables spatially resolved measurements of single …


Ligands Of Therapeutic Utility For The Liver X Receptors., Rajesh Komati, Dominick Spadoni, Shilong Zheng, Jayalakshmi Sridhar Jan 2017

Ligands Of Therapeutic Utility For The Liver X Receptors., Rajesh Komati, Dominick Spadoni, Shilong Zheng, Jayalakshmi Sridhar

Faculty and Staff Publications

Liver X receptors (LXRs) have been increasingly recognized as a potential therapeutic target to treat pathological conditions ranging from vascular and metabolic diseases, neurological degeneration, to cancers that are driven by lipid metabolism. Amidst intensifying efforts to discover ligands that act through LXRs to achieve the sought-after pharmacological outcomes, several lead compounds are already being tested in clinical trials for a variety of disease interventions. While more potent and selective LXR ligands continue to emerge from screening of small molecule libraries, rational design, and empirical medicinal chemistry approaches, challenges remain in minimizing undesirable effects of LXR activation on lipid metabolism. …


Quantification Of Copper Content With Laser Induced Breakdown Spectroscopy As A Potential Indicator Of Offal Adulteration In Beef, Maria Piedad Casado-Gavalda, Yash Dixit, David Geulen, Raquel Cama-Moncunill, Xavier Cama-Moncunill, Maria Markiewicz-Keszycka, Patrick J. Cullen, Carl Sullivan Jan 2017

Quantification Of Copper Content With Laser Induced Breakdown Spectroscopy As A Potential Indicator Of Offal Adulteration In Beef, Maria Piedad Casado-Gavalda, Yash Dixit, David Geulen, Raquel Cama-Moncunill, Xavier Cama-Moncunill, Maria Markiewicz-Keszycka, Patrick J. Cullen, Carl Sullivan

Articles

Laser induced breakdown spectroscopy (LIBS) is an emerging technique in the field of food analysis which provides various advantages such as minimal sample preparation, chemical free, rapid detection, provision of spatial information and portability. In this study, LIBS was employed for quantitative analysis of copper content in minced beef samples spiked with beef liver over three independent batches. Copper content was determined with graphite furnace atomic absorption spectroscopy (GFAAS) in order to obtain reference values for modelling. Partial least square regression (PLSR) was performed to build a calibration and validation model. A calibration model with a high Rcv2 of 0.85 …


Chemical Profiling And Chemical Standardization Of Vitex Negundo Using 13c Nmr, Fabian M. Dayrit, Lolita G. Lagurin, John Daniel J. Magsalin, Anthony R. Zosa Jan 2017

Chemical Profiling And Chemical Standardization Of Vitex Negundo Using 13c Nmr, Fabian M. Dayrit, Lolita G. Lagurin, John Daniel J. Magsalin, Anthony R. Zosa

Chemistry Faculty Publications

Chemical profiling and standardization of the defatted methanol extract of the leaves of Vitex negundo L. were carried out using 13C nuclear magnetic resonance (NMR) analysis followed by chemometric analysis of the chemical shift data. Chemical profile was obtained using a k-means cluster profile and chemical standardization which was achieved using a multivariate control chart. The V. negundo samples were made up of four groups: the training set, submitted samples from production farms, commercial samples, such as tablets, capsules and teas, and experimental samples (samples which were allowed to degrade). Four groups were generated in k-means cluster, which generally corresponded …


Effects Of Silvopasture Establishment On Aqueous And Gaseous Soil N Losses At The University Of New Hampshire Organic Dairy Research Farm, Kathryn Ann Slebodnik Jan 2017

Effects Of Silvopasture Establishment On Aqueous And Gaseous Soil N Losses At The University Of New Hampshire Organic Dairy Research Farm, Kathryn Ann Slebodnik

Honors Theses and Capstones

The expansion of local agriculture in the New England region is putting increased pressure on farmers to expand their arable land base. While clear-cutting is a traditional method of converting forested land to agriculture, it is known for having adverse ecological impacts. To minimize these impacts, farmers can create a silvopasture which incorporates a portion of the original forest canopy into pastures or crop fields. This study evaluates the impact of land-use changes for agriculture on soil nitrogen (N) retention. In particular, this study investigates the differences in soil N turnover, gaseous loss, and aqueous loss among an established forest, …


Synthesis And Characterization Of Amide Linked Triazolyl Glycolipids As Molecular Hydrogelators And Organogelators, Guijun Wang, Anji Chen, Hari P. R. Mangunuru, Jayasudhan Reddy Yerabolu Jan 2017

Synthesis And Characterization Of Amide Linked Triazolyl Glycolipids As Molecular Hydrogelators And Organogelators, Guijun Wang, Anji Chen, Hari P. R. Mangunuru, Jayasudhan Reddy Yerabolu

Chemistry & Biochemistry Faculty Publications

Carbohydrate based small molecular gelators are important classes of compounds which can form useful soft materials with many practical applications. Although many different types of effective gelators have been reported, the rational design of a molecular hydrogelator is still challenging. In this research, we combined the structural features of two classes of monosaccharide based molecular gelators and obtained a new class of glycolipids that can function as molecular gelators. These new compounds were synthesized by introducing a triazole functional group to a protected 2-glucosamine through Cu(i) catalyzed azide/alkyne cycloaddition reaction (CuAAC). A series of eighteen new glycolipids containing 4,6-O …


Complementary Charged Molecular Imprints Of West Nile Virus Antibodies, Julio Rincon Jan 2017

Complementary Charged Molecular Imprints Of West Nile Virus Antibodies, Julio Rincon

Open Access Theses & Dissertations

There is a significant demand for robust and stable receptor molecules that can mimic biological molecules, such as antibodies. Relying only on natural recognition molecules have greatly limited the uses and capabilities of many aspects of health sciences due to product expense and stability. This is especially important in medically underserved areas where the lack of resources and faulty or limited cold-chain makes antibody based diagnostics very difficult to implement.

With molecular imprinting, it is possible to recognize diseases with the added advantage of product stability, long term use, fast preparation and ease of scalability, all while being cost effective. …


Analysis Of Metabolites In The Urine Of Mice With Tyrosinemia Type 1 Using Nmr And Ms, Flora Eason Jan 2017

Analysis Of Metabolites In The Urine Of Mice With Tyrosinemia Type 1 Using Nmr And Ms, Flora Eason

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.


Antimicrobial Activity Of Fractionated Borohydride-Capped And Electrochemical Colloidal Silver, Marjorie M. Markopoulos Jan 2017

Antimicrobial Activity Of Fractionated Borohydride-Capped And Electrochemical Colloidal Silver, Marjorie M. Markopoulos

Browse all Theses and Dissertations

Silver nanoparticles (AgNPs) and ionic silver (Ag+) are known to be broad-spectrum antimicrobial agents. Recent studies show these agents may be an alternative to the most widely used drinking water disinfectant, chlorine. Chlorine is a toxic industrial chemical with a lethal concentration of 430 ppm after 30 minutes. Additionally, chlorine can react with naturally occurring materials to produce a number of disinfection byproducts such as chloroform and trihalomethanes. Some of these byproducts pose cancer risks in addition to other negative impacts to human health. These would be eliminated with the use of Ag+ or AgNPs. The main goal of this …


Metabolic Investigations Of The Molecular Mechanisms Associated With Parkinson’S Disease, Robert Powers, Shulei Lei, Annadurai Anandhan, Darrell D. Marshall, Bradley Worley, Ronald Cerny, Eric D. Dodds, Yuting Huang, Mihalis I. Panayiotidis, Aglaia Pappa, Rodrigo Franco Jan 2017

Metabolic Investigations Of The Molecular Mechanisms Associated With Parkinson’S Disease, Robert Powers, Shulei Lei, Annadurai Anandhan, Darrell D. Marshall, Bradley Worley, Ronald Cerny, Eric D. Dodds, Yuting Huang, Mihalis I. Panayiotidis, Aglaia Pappa, Rodrigo Franco

Robert Powers Publications

Parkinson’s disease (PD) is a neurodegenerative disorder characterized by fibrillar cytoplasmic aggregates of α-synuclein (i.e., Lewy bodies) and the associated loss of dopaminergic cells in the substantia nigra. Mutations in genes such as α -synuclein (SNCA) account for only 10% of PD occurrences. Exposure to environmental toxicants including pesticides and metals (e.g., paraquat (PQ) and manganese (Mn)) is also recognized as an important PD risk factor. Thus, aging, genetic alterations, and environmental factors all contribute to the etiology of PD. In fact, both genetic and environmental factors are thought to interact in the promotion of idiopathic PD, but the mechanisms …


Phage Display To Identify Functional Resistance Mutations To Rigosertib, Nedim Filipovic Jan 2017

Phage Display To Identify Functional Resistance Mutations To Rigosertib, Nedim Filipovic

CMC Senior Theses

In vitro protein selection has had major impacts in the field of protein engineering. Traditional screens assay individual proteins for specific function. Selection, however, analyzes a pool of mutants and yields the best variants. Phage display, a successful selection technique, also provides a reliable link between variant phenotype and genotype. It can also be coupled with high throughput sequencing to map protein mutations; potentially highlighting vital mutations in variants. We propose to apply this technique to cancer therapy. RAF, a serine/threonine kinase, is critical for cell regulation in mammals. RAF can be activated by oncogenic RAS, found in over 30% …


Comparative Proteomic Analyses Of The Parietal Lobe From Rhesus Monkeys Fed A High-Fat/Sugar Diet With And Without Resveratrol Supplementation, Relative To A Healthy Diet: Insights Into The Roles Of Unhealthy Diets And Resveratrol On Function, Aaron M. Swomley, Judy C. Triplett, Jeriel T. Keeney, Govind Warrier, Kevin J. Pearson, Julie A. Mattison, Rafael De Cabo, Jian Cai, Jon B. Klein, D. Allan Butterfield Jan 2017

Comparative Proteomic Analyses Of The Parietal Lobe From Rhesus Monkeys Fed A High-Fat/Sugar Diet With And Without Resveratrol Supplementation, Relative To A Healthy Diet: Insights Into The Roles Of Unhealthy Diets And Resveratrol On Function, Aaron M. Swomley, Judy C. Triplett, Jeriel T. Keeney, Govind Warrier, Kevin J. Pearson, Julie A. Mattison, Rafael De Cabo, Jian Cai, Jon B. Klein, D. Allan Butterfield

Chemistry Faculty Publications

A diet consisting of a high intake of saturated fat and refined sugars is characteristic of a Western-diet and has been shown to have a substantial negative effect on human health. Expression proteomics were used to investigate changes to the parietal lobe proteome of rhesus monkeys consuming either a high fat and sugar (HFS) diet, a HFS diet supplemented with resveratrol (HFS+RSV), or a healthy control diet for 2 years. Here we discuss the modifications in the levels of 12 specific proteins involved in various cellular systems including metabolism, neurotransmission, structural integrity, and general cellular signaling following a nutritional intervention. …


Do Elevated Levels Of Glutathione Decrease The Toxicity Of Plasticizers In Mouse Liver Cells?, Khatoon Albahrani Jan 2017

Do Elevated Levels Of Glutathione Decrease The Toxicity Of Plasticizers In Mouse Liver Cells?, Khatoon Albahrani

All Master's Theses

Phthalates are esters of phthalic acid that play a crucial role in the manufacturing industries for enhancing the properties of plastic materials. Di-(2-ethylhexyl) phthalate (DEHP) is one of the most common phthalates used in a variety of products including food packaging and medical equipment. Their use has caused public health concerns because of their toxic effects on reproductive and developmental processes. This study aims to investigate the response of two mouse hepatoma cell lines to the effects of DEHP and its bioactive metabolite mono (2-ethylhexyl) phthalate (MEHP). Cells were exposed to four concentrations (10, 50, 100, and 300 µM) of …


The T6a Modification Acts As A Positive Determinant For The Anticodon Nuclease Prrc, And Is Distinctively Nonessential In Streptococcus Mutans, Jo Marie Bacusmo, Silvia S. Orsini, Jennifer Hu, Michael Demott, Patrick C. Thiaville, Ameer Elfarash, Mellie June Paulines, Diego Rojas-Benítez, Birthe Meineke, Christopher Deutsch, Dirk Iwata-Reuyl, Patrick A. Limbach, Peter C. Dedon, Kelly C. Rice, Stewart Shuman, Valérie De Crécy-Lagard Jan 2017

The T6a Modification Acts As A Positive Determinant For The Anticodon Nuclease Prrc, And Is Distinctively Nonessential In Streptococcus Mutans, Jo Marie Bacusmo, Silvia S. Orsini, Jennifer Hu, Michael Demott, Patrick C. Thiaville, Ameer Elfarash, Mellie June Paulines, Diego Rojas-Benítez, Birthe Meineke, Christopher Deutsch, Dirk Iwata-Reuyl, Patrick A. Limbach, Peter C. Dedon, Kelly C. Rice, Stewart Shuman, Valérie De Crécy-Lagard

Chemistry Faculty Publications and Presentations

Endoribonuclease toxins (ribotoxins) are produced by bacteria and fungi to respond to stress, eliminate non-self competitor species, or interdict virus infection. PrrC is a bacterial ribotoxin that targets and cleaves tRNALys UUU in the anticodon loop. In vitro studies suggested that the post-transcriptional modification threonylcarbamoyl adenosine (t6A) is required for PrrC activity but this prediction had never been validated in vivo. Here, by using t6A-deficient yeast derivatives, it is shown that t6A is a positive determinant for PrrC proteins from various bacterial species. Streptococcus mutans is one of the few bacteria where the t …


Oxidative Stress And Proteomic Studies Of Mammalian Models Of Age-Related Metabolic Dysfunction In Neurodegenerative Disorders, Aaron M. Swomley Jan 2017

Oxidative Stress And Proteomic Studies Of Mammalian Models Of Age-Related Metabolic Dysfunction In Neurodegenerative Disorders, Aaron M. Swomley

Theses and Dissertations--Chemistry

Expression proteomics is the field of science wherein proteins that make up the cellular proteome are identified both by name and by fold-change. Depending on the application of proteomics, this change in level could be due to internal cellular stressors or introduction of xenobiotics. Global oxidative stress measures use immunohistochemistry to determine the relative level of oxidative stress of macromolecules within the cell. In this dissertation, both global oxidative stress measures and expression proteomics were used in a variety of mammalian models in order to determine the effects of protein upregulation, intranasal insulin administration, and resveratrol supplementation on the cellular …


Synthesis And Development Of Zwitterionic Pei (Zpei) For Optimized Delivery Of Nucleic Acids, Joseph Raleigh Duke Iii Jan 2017

Synthesis And Development Of Zwitterionic Pei (Zpei) For Optimized Delivery Of Nucleic Acids, Joseph Raleigh Duke Iii

Theses and Dissertations--Chemistry

Gene therapy holds promise for the treatment a wide range of diseases ranging from cystic fibrosis to cardiovascular disease to cancer. The need for safe and efficient gene delivery methods remains the primary barrier to human gene therapy. Non-viral vector materials, including polymers, can be designed to be biocompatible and non-immunogenic, but lack the efficiency to be clinically relevant. Gene therapy awaits the development of new materials that are both safe and efficient. Here, we have synthesized a series of modified zwitterionic polymers based on the common transfecting agent polyethylenimine (PEI). Using a variety of biochemical and biophysical methods we …


Extraction And Quantification Of Sinapinic Acid From Irish Rapeseed Meal And Assessment Of Angiotensin-I Converting Enzyme (Ace-I) Inhibitory Activity, Leah Quinn, Steven Gray, Steve Meaney, Stephen Finn, Padraig Mcloughlin, Maria Hayes Jan 2017

Extraction And Quantification Of Sinapinic Acid From Irish Rapeseed Meal And Assessment Of Angiotensin-I Converting Enzyme (Ace-I) Inhibitory Activity, Leah Quinn, Steven Gray, Steve Meaney, Stephen Finn, Padraig Mcloughlin, Maria Hayes

Articles

Phenolic compounds, including phenolic acids, are known to play a protective role against the development of cardiovascular disease. The aim of this work was to generate a phenolic acid extract from Irish rapeseed meal, to determine the quantity of sinapinic acid (SA) in this fraction and to assess the ability of this fraction to inhibit the enzyme angiotensin-I converting enzyme (ACE-I; EC 3.4.15.1). A crude phenolic extract (fraction 1), free phenolic acid containing extract (fraction 2), and an extract containing phenolic acids liberated from esters (fraction 3) were generated from Irish rapeseed meal using a methanol:acetone:water solvent mixture (7:7:6). The …


Feasibility Of Laser-Induced Breakdown Spectroscopy (Libs) As An At-Line Validation Tool For Calcium Determination In Infant Formula, Xavier Cama-Moncunill, Maria Markiewicz-Keszycka, Yash Dixit, Raquel Cama-Moncunill, Maria Piedad Casado-Gavalda, Patrick J. Cullen, Carl Sullivan Jan 2017

Feasibility Of Laser-Induced Breakdown Spectroscopy (Libs) As An At-Line Validation Tool For Calcium Determination In Infant Formula, Xavier Cama-Moncunill, Maria Markiewicz-Keszycka, Yash Dixit, Raquel Cama-Moncunill, Maria Piedad Casado-Gavalda, Patrick J. Cullen, Carl Sullivan

Articles

In this study, a 150 mJ laser-induced breakdown spectroscopy (LIBS) system was assessed to determine calcium content in infant formula (IF) samples. LIBS is a promising emission spectroscopic technique for elemental analysis, which offers advantages over conventional methods such as real-time analyses, little to no sample preparation and ease of use. The aim of this work was to evaluate the feasibility of LIBS as an at-line tool for IF manufacturing. To this end, IF mixtures with varying content of calcium were prepared over a range (approx. 1.5–7 mg/g of calcium) selected to be in conformity with the guidelines provided by …


The Maculoprotective Effect Of A Thiol Antioxidant In Retinal Degeneration Models, Hsiu-Jen Wang Jan 2017

The Maculoprotective Effect Of A Thiol Antioxidant In Retinal Degeneration Models, Hsiu-Jen Wang

Doctoral Dissertations

"Age-related macular degeneration (AMD) is a leading cause of irreversible blindness among adults, age 60 and older, in developed countries. While oxidative stress is implicated in the pathogenesis of AMD, clinical studies have shown that dietary antioxidants can delay progression of AMD. Currently, there is no FDA-approved treatment for AMD. Therefore, we hypothesized that N-acetylcysteine amide (NACA), a thiol antioxidant, would protect retinal pigment epithelium and impede the progression of retinal degeneration. The goal of this work was to evaluate the efficacy of NACA in preventing retinal pigment epithelial cell and photoreceptor death in AMD models. To achieve this, we …


The Potential Of Atmospheric Air Cold Plasma For Control Of Bacterial Contaminants Relevant To Cereal Grain Production, Agata Los, Dana Ziuzina, Daniela Boehm, Patrick J. Cullen, Paula Bourke Jan 2017

The Potential Of Atmospheric Air Cold Plasma For Control Of Bacterial Contaminants Relevant To Cereal Grain Production, Agata Los, Dana Ziuzina, Daniela Boehm, Patrick J. Cullen, Paula Bourke

Articles

The aim of this work was to investigate the efficacy of dielectric barrier discharge atmospheric cold plasma (DBD ACP) against bacteria associated with grains quality and safety. ACP inactivation efficacy was tested against biofilms formed by different strains of E. coli, Bacillus and Lactobacillus in grain model media and against B. atrophaeus endospores either in grain media or attached on abiotic surfaces. Effects were dependent on bacterial strain, media composition and mode of ACP exposure. ACP treatment for 5min reduced E. coli spp., B. subtilis and Lactobacillus spp. biofilms by >3 log10, whereas insignificant reductions were achieved for B. atrophaeus. …


Impact Of Atmospheric Pressure Nonequilibrium Plasma Discharge On Polymer Surface Metrology, Laurence Scally, James Lalor, Patrick J. Cullen, Vladimir Milosavljevic Jan 2017

Impact Of Atmospheric Pressure Nonequilibrium Plasma Discharge On Polymer Surface Metrology, Laurence Scally, James Lalor, Patrick J. Cullen, Vladimir Milosavljevic

Articles

Due to the attraction of plasma technologies as a clean and efficient means of surface modification, significant research has gone into the physical and chemical aspects of polymer functionalization. In this study, it was shown that the use of an atmospheric plasma jet can efficiently modify the surface of polyethylene terephthalate samples and change their hydrophobic properties to more hydrophilic characteristics. The dependence on the changes with respect to time, distance, and atomic oxygen (O I) intensity were considered as factors. It was found that with closer proximity to the plasma source (without causing thermal degradation) and with increasing levels …


Quantification Of Trace Metals In Infant Formula Premixes Using Laser-Induced Breakdown Spectroscopy, Raquel Cama-Moncunill, Maria Piedad Casado-Gavalda, Xavier Cama-Moncunill, Maria Markiewicz-Keszycka, Yash Dixit, Patrick J. Cullen, Carl Sullivan Jan 2017

Quantification Of Trace Metals In Infant Formula Premixes Using Laser-Induced Breakdown Spectroscopy, Raquel Cama-Moncunill, Maria Piedad Casado-Gavalda, Xavier Cama-Moncunill, Maria Markiewicz-Keszycka, Yash Dixit, Patrick J. Cullen, Carl Sullivan

Articles

Infant formula is a human milk substitute generally based upon fortified cow milk components. In order to mimic the composition of breast milk, trace elements such as copper, iron and zinc are usually added in a single operation using a premix. The correct addition of premixes must be verified to ensure that the target levels in infant formulae are achieved. In this study, a laser-induced breakdown spectroscopy (LIBS) system was assessed as a fast validation tool for trace element premixes. LIBS is a promising emission spectroscopic technique for elemental analysis, which offers real-time analyses, little to no sample preparation and …


Quantification Of Rubidium As A Trace Element In Beef Using Laser Induced Breakdown Spectroscopy, Yash Dixit, Maria Piedad Casado-Gavalda, Raquel Cama-Moncunill, Xavier Cama-Moncunill, Patrick J. Cullen, Carl Sullivan Jan 2017

Quantification Of Rubidium As A Trace Element In Beef Using Laser Induced Breakdown Spectroscopy, Yash Dixit, Maria Piedad Casado-Gavalda, Raquel Cama-Moncunill, Xavier Cama-Moncunill, Patrick J. Cullen, Carl Sullivan

Articles

This study evaluates the potential of laser induced breakdown spectroscopy (LIBS) coupled with chemometrics to develop a quantification model for rubidium (Rb) in minced beef. A LIBSCAN 150 system was used to collect LIBS spectra of minced beef samples. Beef liver was used to spike the Rb levels in minced beef. All samples were dried, powdered and pelleted using a hydraulic press. Measurements were conducted by scanning 100 different locations with an automated XYZ sample chamber. Partial least squares regression (PLSR) was used to develop the calibration model, yielding a calibration coefficient of determination (Rc2) of 0.99 and a root …