Digital Commons Network^™

Characterization Of Extracellular Vesicles Isolated From Human Milk Using A Precipitation-Based Method, Diana C. Bickmore, John Miklavcic

Food Science Faculty Articles and Research

Extracellular vesicles (EV) function in intercellular communication, and those in human milk may confer immunologic benefits to infants. Methods of EV isolation such as ultracentrifugation (UC) may not be feasible for the study of EVs in human milk due to the need for large sample volume. A technique to isolate EVs from a small volume of human milk using a precipitation reagent is described herein. Electron microscopy, nanoparticle tracking analysis, and semi-quantitative antibody array were conducted to confirm isolation of human milk EVs. Count, size, protein content, and fatty acid quantification of EVs were determined. This isolation technique yielded 8.9 …

Analysis Of The Correlation Between Re Filament Surface Features And Tims Performance, Christopher J. Mihal

Theses and Dissertations

Thermal Ionization Mass Spectrometry (TIMS) is an invaluable tool in nuclear forensics as it enables isotopic assays of actinides to be measured, permitting analysis to include special nuclear material isotopic assays, nuclear reactor monitoring, and treaty verification. In one method of measurement for the TIMS system, samples are deposited in solution form on high-purity rhenium filaments. The filaments are heated to evaporate the solvent, and then further heated to cause sample ionization, permitting the sample to be transmitted through a magnetic field which separates ions based on mass to charge ratio into detectors for counting. Heavier ions will be deflected …

Effect Of Chemical Treatment On The Physical And Mechanical Properties Of Flax Fibers: A Comparative Assessment, Suhas Yeshwant Nayak, Srinivas Shenoy Heckadka, Aashna Seth, Shrinivasa Prabhu

Open Access archive

In the present study, flax fibers sorted in two batches were considered for treatment. Set one fibers were treated with chemical reagents - KMnO4and acetone for durations of 10, 20 and 30min respectively. The second batch of fibers was treated with stearic acid in ethanol for durations of 24h and 36h. Physical properties namely diameter and density were determined. The treated fibers were also tested to determine their tensile and interfacial adhesion strength. A comparison was drawn between untreated fibers and fibers treated with different treating media. A decrement in the diameter of the fibers with increasing duration of treatment …

Exploring The Use Of Pulsed Erbium Lasers To Retrieve A Zirconia Crown From A Zirconia Implant Abutment, Ahmed Elkharashi, Kinga Grzech-Leśniak, Janina Golob Deeb, Aous A. Abdulmajeed, Sompop Bencharit

General Practice Publications

Background

Removal of cement-retained implant fixed restorations when needed, can be challenging. Conventional methods of crown removal are time consuming and costly for patients and practitioners. This research explored the use of two different types of pulsed erbium lasers as a non-invasive tool to retrieve cemented zirconia crowns from zirconia implant abutments. Materials and methods

Twenty identical zirconia crowns were cemented onto 20 identical zirconia prefabricated abutments using self-adhesive resin cement. The specimens were divided into two groups for laser assisted crown removal; G1 for erbium-doped yttrium aluminum garnet laser (Er:YAG), and G2 for erbium, chromium-doped yttrium, scandium, gallium and …

Light And Scanning Electron Microscopic Examination Of The Saanen Goat Heart, Sedef Selvi̇ler Si̇zer, Yonca Beti̇l Kabak, Murat Kabak

Turkish Journal of Veterinary & Animal Sciences

It is important to know the morphological structure of the heart, which is a vital organ of the body, in detail. For this reason, we aimed to examine the morphological structure of the Saanen goat heart using light and scanning electron microscopy (SEM). A total of thirteen Saanen goat hearts were used in the study. To demonstrate the histological structure of the heart, samples taken from 9 hearts were fixed in 10% formaldehyde solution and blocked in paraffin after routine histological procedures. Histological staining was performed on the sections taken from the blocks. Four hearts were fixed in a 2.5% …

Insecticidal Effect Of Diatomaceous Earth And Dolomite Powder Against Corn Weevilsitophilus Zeamais Motschulsky, 1855 (Coleoptera: Curculionidae), Alyssa Cristina Oliveira Freitas, Adriana Aparecida Sinopólis Gigliolli, Ronaldo Roberto Tait Caleffe Caleffe, Helio Conte

Turkish Journal of Zoology

Sitophilus zeamais Motschulsky, 1855 (Coleoptera: Curculionidae) which develops inside the grain, is an aggressive pest of stored grains. Here, we evaluated the efficiency of diatomaceous earth (DE), Diatomita CI/325 CX, and dolomite (DOL), Dolomita Dr. Kanyo, against S. zeamais reared on corn under laboratory conditions and observed external alterations on treated insects using scanning electron microscopy (SEM). Insects treated with both DE and DOL were impregnated with particles on the body surface, and they showed 100% mortality after 10 days of exposure. Damages caused by inert dusts may have contributed to dehydration and desiccation, consequently, leading insects to death. Thus, …

Highly Improved Electrocatalytic Oxidation Of Dimethylamine Borane On Silvernanoparticles Modified Polymer Composite Electrode, Çağri Ceylan Koçak, Süleyman Koçak, Şükri̇ye Karabi̇beroğlu, Zekerya Dursun

Turkish Journal of Chemistry

Dimethylamine borane (DMAB) is a promising fuel alternative for fuel cell applications. In this work cyclic voltammetric behavior of DMAB was investigated on the polymerized aminophenol film decorated with Ag nanoparticles in alkaline media. The polymer film was formed on the glassy carbon electrode by electrochemical technique and then, the surface was modified with Ag nanoparticles. The surface of the modified electrode was identified by scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and electrochemical impedance spectroscopy techniques. The developed electrode has displayed high electrocatalytic activity for DMAB oxidation in alkaline media depending on the supporting electrolyte concentration. Experimental …

An In-Vitro Model To Understand Osteoblast Mediated Bone Mineralization, Vaikhari Abhay Marathe

Theses - ALL

Musculoskeletal diseases are widespread, and they affect hundreds of millions of people all around the world. Bone defects occurs due to various reasons such as surgeries, fracture and diseases. These bone defects need a surgical intervention and are generally treated with state-of-the-art grafting techniques such as natural bone grafts and implants. However, even the best available corrective treatments have several limitations such as availability, disease transfer, donor site scarcity, and immune rejection. Bone remodeling techniques which would support natural bone regeneration upon graft implantation, can be used to maximize the efficiency of current grafting techniques. In this study, our goal …

Properties Of New York/New Jersey Harbor Sediments, K. W. Jones, Huan Feng, E. A. Stren, U. Neuhäusler, J. Osán, N. Marinkovic, Z. Song

Huan Feng

Sediments found in waterways around the world may contain toxic compounds of anthropogeilic origin that can harm the environment and human health. As a result, it is often necessary to remove them and find disposal methods that are environmentally and economically acceptable. Here, we report on results obtained in an experimental program to characterize the nature of the sediment contamination. The objective was to gain a better understanding of the properties of the sediments to develop better methods for understanding the fate and transport of the contaminants and for improving methods for their removal from the sediments. Our investigations made …

Reaction Induced Morphology Changes Of Tetracene And Pentacene Surfaces, Feifei Li, Jacob W. Ciszek

Chemistry: Faculty Publications and Other Works

Morphology plays a critical role in determining the properties of solid-state molecular materials, yet fluctuates wildly as these materials undergo reaction. A prototypical system, a vapor–solid Diels–Alder reaction of tetracene and pentacene thin-films, is used to observe the evolution of morphology features as the reaction transitions from surface to bulk. The initial stages of reaction display little topographical change as measured by atomic force microscopy (AFM) and scanning electron microscopy (SEM), and substrates are coated with a uniform layer of product 1–2 molecules thick, as determined by energy-dispersive X-ray (EDX) spectroscopy. The highly textured surfaces of late stage reactions are …

Studies Of Dislocation Density Quantification Via Cross-Correlation Ebsd, Samuel Searle Friedbaum

Theses and Dissertations

One conventional method for studying dislocations uses the Transmission Electron Microscope (TEM), a complex and expensive piece of equipment which requires extensive specimen preparation in order to thin the specimens to electron transparent thickness. Newer High Resolution Electron Backscatter Diffraction (HREBSD) methods of determining geometrically necessary dislocation content via cross-correlation promise to be able to produce estimates of the dislocation density of the sample over a larger area with considerably less preparation time and using a much more accessible instrument. However, the accuracy of the new EBSD technique needs more experimental verification, including consideration of possible changes in the specimen …

Synchrotron Radiation Analysis Of Daguerreotypes: Surface Characterization, Electrocleaning, And Preservation, Madalena S. Kozachuk

Electronic Thesis and Dissertation Repository

The first commercially viable photographic image, the daguerreotype, captured images from 1839 to 1860. While daguerreotypes provide a significant historical record of 19^th century individuals and events, deterioration now disfigures many of these images. This work describes the application of synchrotron radiation (SR) to the study of daguerreotypes.

Three goals were addressed in this thesis: 1) to utilize SR to further elucidate the physics and chemistry of the daguerreotype and how the surface varies with time, 2) to study the effects of the electrocleaning system on the daguerreotype surface, and 3) to propose suggestions to improve their preservation and …

Bleached Chondrules And The Possible Influence Of Aqueous Alteration, Robert P. Kostynick

Geology Undergraduate Honors Theses

Aqueous alteration, chemical or petrologic change through the addition of water, is a proposed secondary effect of ordinary chondrites. Some minimally metamorphosed chondrites have been noted to have strong signs of aqueous alteration (Weisberg et al., 2006), but the degree of the effect in other chondrites is not clear. There is a specific chondrule type called “bleached chondrules” in which aqueous alteration is proposed to occur in a widespread fashion for all metamorphic grades (Grossman et al., 2000). Using transmitted optical microscopy (OM) and scanning electron microscopy (SEM) at Portland State University, this report obtained chemical and petrological data of …

The Family Oxyopidae In South Texas (Araneae: Oxyopidae), Amelia Solis

Theses and Dissertations

The genital structures of most spiders are poorly studied in respect to their morphology. Conventional taxonomic practice recommends utilizing light dissecting microscopy as the preferred method of investigation. Because of this, the understanding of genital morphology is incomplete and further studies with more advanced equipment and higher magnifications should be done focusing on these important structures. Features found in both male and female genitalia can help identify new and existing species, as well as generate new data to construct new taxonomic groups. Five species belonging to the Family Oxyopidae: Oxyopes acleistus, O. apollo, O. salticus, O. tridens, and Peucetia viridans, …

X-Ray Determination Of Compressive Residual Stresses In Spring Steel Generated By High-Speed Water Quenching, Diego E. Lozano, George E. Totten, Yaneth Bedolla-Gil, Martha Guerrero-Mata, Marcel Carpio, Gabriela M. Martinez-Cazares

Mechanical and Materials Engineering Faculty Publications and Presentations

Automotive components manufacturers use the 5160 steel in leaf and coil springs. The industrial heat treatment process consists in austenitizing followed by the oil quenching and tempering process. Typically, compressive residual stresses are induced by shot peening on the surface of automotive springs to bestow compressive residual stresses that improve the fatigue resistance and increase the service life of the parts after heat treatment. In this work, a high-speed quenching was used to achieve compressive residual stresses on the surface of AISI/SAE 5160 steel samples by producing high thermal gradients and interrupting the cooling in order to generate a case-core …

Micron-Sized Spinel Crystals In High Level Waste Glass Compositions: Determination Of Crystal Size And Crystal Fraction, C. (Charmayne) E. Lonergan, K. Akinloye-Brown, J. Rice, V. Gervasio, N. Canfield, M. J. Schweiger, J. D. Vienna

Materials Science and Engineering Faculty Research & Creative Works

The compositions utilized for immobilization of high-level nuclear wastes (HLW) are controlled using glass property models to avoid the deleterious effects of crystallization in the high-level waste (HLW) vitrification melters. The type and size of the crystals that precipitate during melter operations (typically at 1150 °C) and idling (∼1000 °C) are significantly impacted by glass composition and thermal history. This study was conducted to measure the impact of melt composition and heat treatment temperature on crystal size and fraction. A matrix of 31 multi-component glasses canvasing the expected Hanford HLW compositional space was developed and the glasses fabricated, and heat …

Using Er:Yag Laser To Remove Lithium Disilicate Crowns From Zirconia Implant Abutments: An In Vitro Study, Janina Golob Deeb, Sompop Bencharit, Nishchal Dalal, Aous Abdulmajeed, Kinga Grzech-Leśniak

Periodontics Publications

Background
When implants are restored with cement-retained restorations, prosthetic retrievability can be difficult and often requires sectioning using rotary instruments. Sometimes repeated removals of a cement-retained implant crown are needed such as for treatment of peri-implantitis or immediate implant provisionalization. The purpose of this study was to evaluate the effect of erbium-doped yttrium aluminum garnet (Er:YAG) laser as a non-invasive treatment modality to remove lithium disilicate crowns from zirconia implant abutments following long-term cementation, repetitive debonding and re-cementation, and short-term retrieval.

Material and methods
Twenty identical lithium disilicate crowns were cemented onto zirconia prefabricated abutments using composite resin cement. Ten …

On The Use Of Vibrational Spectroscopy And Scanning Electron Microscopy To Study Phenolic Extractability Of Cooperage Byproducts In Wine, Berta Baca‑Bocanegra, Julio Nogales‑Bueno, Brian Gorey, Francisco José Heredia, Hugh Byrne, José Miguel Hernández‑Hierro

Articles

Wood is an important source of phenolic compounds, which can be transferred to wine during aging process, improving its properties, from an organoleptic point of view. Therefore, understanding and optimizing the extractability of phenolic compounds from wood are crucial in the oenological field. The structural composition of oak wood samples has been evaluated using Raman and attenuated total reflectance Fourier transform infrared (ATR–FTIR) spectroscopies, and their main spectral features have been linked to phenolic compound extractabilities, as measured by classic chemical analyses. To support the analysis, microscopic images of the samples were also recorded using scanning electron microscopy (SEM). The …

Nanoindentation Characterization On Local Plastic Response Of Ti-6al-4v Under High-Load Spherical Indentation, Yan Wen, Lechun Xie, Zhou Wang, Liqiang Wang, Weijie Lu, Laichang Zhang

Research outputs 2014 to 2021

After high-load spherical indentation treatment, the variations of hardness on the plastic zone of Ti-6Al-4V were investigated via nanoindentation method. The hardness within the center of plastic zone was measured by nanoindenter, and the magnitude decreased gradually along the depth, which were caused by the different extent of plastic deformation under the residual imprint. The microstructure of indentation were observed using scanning electron microscope (SEM) before and after surface etching, and the results showed that the microhardness revealed the average hardness of α and β phases of Ti-6Al-4V. The maximum hardness reached 6.438 GPa in the depth of 132 μm. …

Effect Of Pretreatment Process On Scale Formation In The Re-Boiler Section Of Monoethylene Glycol Regeneration Plant, Ammar Al Helal, Adam Soames, Stefan Iglauer, Ahmed Barifcani, Rolf Gubner

Research outputs 2014 to 2021

Monoethylene glycol (MEG) regeneration plants often use pretreatment vessels to precipitate divalent cations, such as Fe²⁺, Ca²⁺, and Mg²⁺, in order to avoid or reduce fouling in downstream reboilers and heat exchangers. This pretreatment process operates under alkaline conditions and moderate temperatures (~ 80 °C) to accelerate the formation of low-solubility divalent salts. The objective of the present research was to determine whether the pretreatment process could be minimized, without negatively impacts on the MEG regeneration process from to the formation of scale on the heater bundle in the presence of low concentrations of …

Transmission Electron Microscopy Analysis Of Silicon-Doped Beta-Gallium Oxide Films Grown By Pulsed Laser Deposition, Cynthia Thomason Bowers

Browse all Theses and Dissertations

Due to the large band gap of β-Ga2O3 and recent improvements toward high quality native substrates and the ability to shallow dope epitaxial β-Ga2O3 it is an attractive material for applications in power electronic devices. Such devices require advances in the areas of thin film growth and carrier concentration control to deliver high mobility films appropriate for the device structures. Transmission electron microscopy (TEM) analysis can provide information concerning doping, crystal structure, and internal strain which will be valuable to assess the role of defects and impurities on the transport properties for feedback to optimize the bulk and epitaxial growth …

Fruit And Seed Macro- And Micromorphologies Of The Genus Matthiola (Brassicaceae) In Turkey And Their Taxonomic Value, Ayla Kaya, Murat Ünal, Abdurrahman Sefali, Esra Marti̇n

Turkish Journal of Botany

Macro- and micromorphological features of fruit and seeds belonging to 12 taxa genera of Matthiola W.T.Aiton were studied via stereomicroscope and scanning electron microscope. In macromorphological studies, the following variables were investigated: the shape, size, and color of fruit and seeds; the length of fruiting pedicel; the structure of the median vein; stigma (horns); and trichome properties and density in fruit. In micromorphological studies, the presence or absence of seed wings, seed coat pattern in disc and wing, and epidermal cell shape in disc and wing were determined. According to our findings, all characters of fruit and seeds are extremely …

Nutlet Structures Of Subsection Fragiles Of The Genus Stachys (Lamiaceae) From Turkey And Their Systematic Applications, Mehmet Cengi̇z Karai̇smai̇loğlu, Özal Güner

Turkish Journal of Botany

This paper includes the morphological and anatomical characters of the nutlets of 7 endemic species of the subsection Fragiles of the genus Stachys (Lamiaceae) from Turkey and the systematic significance of these characteristics, using one-way analysis of variance and cluster and principal component analyses. Morphological characters such as the dimensions, shapes, colors, and surfaces of the nutlets were studied using light and scanning electron microscopes. The structures and thicknesses of the pericarp and endosperm layers, as well as the sizes of the cotyledon in the nutlets, were anatomically studied. The outcomes revealed that the taxa varyfrom each other in terms …

Preformed-Particle-Gel Placement And Plugging Performance In Fractures With Tips, Ze Wang, Baojun Bai

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Preformed-particle gels (PPGs) have been applied for reducing excessive water production caused by fractures in reservoirs. A portion of the fractures existing in reservoirs is composed of a void part and a fracture tip. The PPG placement behavior and plugging performance could be mainly affected by the fracture tips. A fracture with a tip, called a "partially open fracture" in this paper, was designed to investigate the placement and water-plugging performance of PPG. Cylindrical sandstone cores were used to manufacture partially open fractures. Pressure data of PPG injection, post-gel water breakthrough, and stable injection were analyzed to investigate the PPG …

Analysis Of Frozen Desserts Using Low-Temperature Scanning Electron Microscopy (Lt-Sem), Kinsey Elizabeth Macdonald

All Theses

Commercial vanilla ice cream and other frozen desserts from the United States were analyzed for ice crystal length using low-temperature scanning electron microscopy (LT-SEM). Average ice crystal length was determined using multiple micrographs of each sample/product. Out of the products tested, 11 out of 15 samples had an average ice crystal length above the consumer sensory threshold limit of 55 µm. Products containing stabilizers tended to have smaller average ice crystal lengths than products without stabilizers. With a few exceptions, lower fat products tended to have larger ice crystals because there was less fat to stabilize the ice crystals. Four …

Coagulation Factor Xiiia: Biochemical Properties Underlying Physiological Function., Boris Anokhin

Electronic Theses and Dissertations

Factor XIIIA (FXIIIA) is a transglutaminase that crosslinks intra- and extracellular protein substrates. The oligomeric state of active FXIIIA remains controversial, and the present work commenced with addressing this issue. The results of size exclusion chromatography and analytical ultracentrifugation confirmed a dimeric state for zymogen and, for the first time, indicated a monomeric state for the active FXIIIA in solution. Comparing sedimentation properties of proteolytically and nonproteolytically activated FXIIIA suggested conformational and functional differences between the two forms. Those differences were further assessed in a series of catalytic activity studies. Kinetic analysis revealed affinity for the glutamine substrate was higher …

Pollen Evidence Of Medicine From An Embalming Jar Associated With Vittoria Della Rovere, Florence, Italy, Karl Reinhard, Kelsey B. Lynch, Annie Larsen, Braymond Adams, Leon Higley, Marina Milanello Do Amaral, Julia Russ, Donatella Lippi, Johnica J. Morrow, Dario Piombino-Mascali

Karl Reinhard Publications

Various samples of human viscera fragments, sponges, and cloth were collected from embalming jars belonging to members of the Medici family of Florence. One jar was labeled with the name Vittoria della Rovere, who died in March of 1694. This jar contained viscera fragments that were identified as a section of collapsed intestine. The intestine of the Vittoria della Rovere sample contained a large concentration of pollen belonging to the Myrtaceae family. The Myrtaceae pollen was sometimes observed in clusters during analysis, which is indicative of purposeful ingestion of flowers, buds, or a substance derived from floral structures. Thus, the …

Development Of Low Cost, Environmentally Friendly And High Strength Carbon Foams From Bread And Cake, Laura Mountain-Tuller

Materials Engineering

Carbon foam is a high niche material that consists of a highly porous, three-dimensional cellular network that is characterized by extremely high strength-to-weight ratios and low thermal conductivity. Due to these properties, carbon foams excel in structural and thermal applications, especially in the aerospace industry. Typically, carbon foams are formed through a heating process called pyrolysis of polymer precursors with high carbon content. This process is done at high temperatures in an oxygen free environment. These precursors are expensive to make and use toxic chemicals to produce, therefore, there is a push to find an environmentally friendly and cost-effective method …

In Situ Sem Solidification Study Of Ga And Egain: A Characterization Technique For Monitoring The Microstructural Evolution Of Liquid Metals, Jeremy Geovann Del Aguila

Materials Engineering

Scanning electron microscopy (SEM) video recording is used to characterize the solidification of small volumes of 99.999% pure gallium (Ga) and eutectic gallium-indium (eGaIn) under a high vacuum environment. Specimen are superheated to 55℃ using a hot plate, cast into spherical droplets, and cooled in situ by means of a Peltier cooling stage. Special attention is given to the preparation of the specimen prior to viewing because of gallium and its alloys’ nature to form an oxide layer when melted and air cooled. The oxide acts as a skin that inhibits the observation of microstructural features during solidification. Heated samples …

Alkali Activated Slag Characterization By Scanning Electron Microscopy And X-Ray Microanalysis, Najat A. Alharbi

Theses

Blast furnace slag is a non-metallic byproduct generated by the production of iron and steel in a blast furnace at temperatures in the range of 1400°-1600° C. The alkali activation of blast furnace slag has the potential to reduce the environmental impact of cementitious materials and to be applied in geographic zones where weather is a factor that negatively affects performance of materials based on Ordinary Portland Cement. Alkali-activated blast furnace slag cements have been studied since the 1930s due to its high compressive strength; they can exceed 100 MPa in 28 days. The low Ca/Si ratio in slag improves …