Physical Sciences and Mathematics Commons^™

Towards More Efficient Collaborative Distributed Data Analysis And Learning, Zixia Liu

Electronic Theses and Dissertations, 2020-2023

Modern information era gives rise to the persistent generation of large amounts of data with rapid speed and broad geographical distribution. Obtaining knowledge and understanding via analysis and learning from such data have invaluable worth. Features of such data analytical tasks commonly include: data can be large scale and geographically distributed; computing capability demand can be enormous; tasks can be time-critical; some data can be private; participants can have heterogeneous capabilities and non-IID data; and multiple simultaneously submitted data analytical tasks can be possible. These bring challenges to contemporary computing infrastructure and learning models. In view of this, we develop …

Observation Of Anisotropic Properties In Topological Quantum Materials, Gyanendra Dhakal

Electronic Theses and Dissertations, 2020-2023

The discovery of the three-dimensional topological insulator (TI) has enormously impacted our understanding of quantum materials. These novel materials are characterized by the topology rather than some order parameters. The TIs are the materials that exhibit insulating properties in the bulk while possessing the metallic state on the surface. These surface states are protected by time-reversal symmetry; as a result, the electrons featuring surface states are spin-polarized. After the discovery of TIs, other topological semimetallic (TSM) states were discovered, which enhanced the understanding and widened the reach of topological materials. Discoveries of various topological phases such as Dirac, Weyl, nodal …

Volume Bragg Gratings With Complex Phase Structures: A Three-Dimensional Foundation For Laser-Beam Engineering, Lam Mach

Electronic Theses and Dissertations, 2020-2023

Bragg diffraction is a natural phenomenon that arises from the coherent interference of scattered waves in multilayer structures with a well-defined periodicity. In practice, the physical size of these multilayer structures varies depending on the intended application, from micrometer-thick dielectric mirrors with tens of layers to centimeter-long Bragg gratings with ten-thousands of layers. The scope of this work centers around a unique class of multilayer elements developed in bulk photo-thermo-refractive (PTR) glass – the volume Bragg grating (VBG). The content of this thesis places an emphasis on the volume nature of these Bragg devices, implying a three-dimensional structure whereupon arbitrary …

Design Of A High-Power Terahertz Emitter Array Using A High-Temperature Superconductor, Ruqayyah Shouk

Electronic Theses and Dissertations, 2020-2023

By applying a dc voltage V across the stack of intrinsic Josephson junctions naturally present in the high-temperature superconductor consisting of two parts bismuth, two parts strontium, one part calcium, two parts copper, and a bit more than eight parts oxygen, several groups have been able to obtain coherent THz emission at output powers in the µW range. In order to enhance the output power well into the mW range suitable for many applications, we have studied a compact design of a stand-alone mesa array with gold layers on the top and bottom of the superconductor. In this design, an …

Surface Engineering For Controlled Growth And Deposition Of Nanomaterials - Assembly And Design At The Nano-Microscale, David Fox

Electronic Theses and Dissertations, 2020-2023

Materials with nanoscale dimensions offer several important benefits over bulk materials (e.g. increased surface area, low-cost, deviation from bulk properties, etc.). Such materials are critical components for next-generation energy storage materials, optoelectronic devices, and catalyst systems. However, these materials are often processed in liquid media, and their diminutive structures are fragile in the presence of capillary forces. As such, preparing uniform and stable nanomaterial coatings is a significant challenge. Herein, we discuss an approach where the substrate itself is factored into the assembly and growth of these materials. First, nanoporous surfaces were utilized to achieve a uniform deposition of one-dimensional …

Terahertz Spintronics With Antiferromagnetic Insulators, Gyan Khatri

Electronic Theses and Dissertations, 2020-2023

The existence of the THz gap in the electromagnetic spectrum is not only preventing the advancement of several technologies but also hindering research and developmental activities due to a lack of research facilities operating in the gap region. There is a plethora of materials with dynamics lying in the THz gap region whose study could potentially lead to the development of new technologies for the generation, detection, and processing of THz signals. Antiferromagnets are gaining recent interest due to their high frequency dynamics lying in the THz region, and their potential uses as active elements in THz spintronics devices have …

Raman Excitation Laser Effects On Peak Parameters And Peak Metamorphic Temperatures Of Primitive Carbonaceous Chondrites, Amy Lebleu-Debartola

Electronic Theses and Dissertations, 2020-2023

MicroRaman (µRaman) spectroscopy is often regarded as a non-destructive technique, utilized to analyze limited materials, both terrestrial and extraterrestrial. Carbonaceous chondrite meteorites are of particular interest but they are dark (low albedo) materials, and thus absorb the majority of incident visible light. Raman excitation lasers can induce considerable localized heating, even when low laser powers are used. It has been previously suggested to utilize low power lasers of =0.4 mW to minimize damaging carbonaceous samples in several fields, including Meteoritics, Geology, Chemistry, and Paleontology. Peak Metamorphic Temperatures (PMT) experienced by the meteorite can be estimated from Raman fitting parameters related …

Electrochemical Gelation Of Metal Chalcogenide Quantum Dots, Chathuranga Chinthana Hewa Rahinduwage

Wayne State University Dissertations

Quantum dots (QDs) are attractive because of their unique size-dependent optical and electronic properties and high surface area. They are tested in research for diverse applications, including energy conversion, catalysis, and sensing. Assembling QDs into functional solid-state devices while preserving their attractive properties is a challenge. Methods currently under the research are not effective in directly fabricating QDs onto devices, making large area assemblies, maintaining the high surface area by forming 3D porous structures, and conducting electricity for applications such as sensing. QD gels are an example of QD assemblies that consist of a 3D porous interconnected QD network. They …

Long Island Horseshoe Crab Network Annual Inventory Report, Cercom, Molloy University, John Tanacredi Ph.D., Kyle F. Maurelli

CERCOM Reports

CERCOM monitors 115 beach locations from Brooklyn – Montauk during the optimal Limulus Polyphemus breeding season. These beach surveys take place for approximately 15 weeks, ranging from May - August. These beach locations are marked specifically using GPS coordinates, to assure the same location is visited each year. Students and volunteers are required to attend a HSC Survey training orientation led by CERCOM’s research assistant, Mr. Kyle Maurelli. Surveying is done around tide and moon cycles (New/Full Moon). Each site takes about 1-2 hours and data is recorded along an approximate 1 mile distance. Walking along the water’s edge the …

Tolle Lege Works Published In 2022, Mcquade Library

Bibliographies

Compiled Tolle Lege bibliography of works published by members of the Merrimack College Community in 2022. Works include journal articles, books, book chapters, conference presentations and posters, and more.

Examining Trends And Experiences Of The Last Four Years Of Socially Engineered Ransomware Attacks, William Seymour

Cybersecurity Undergraduate Research Showcase

This study examines and reports the trends of social engineering-based ransomware attacks over the past four years from three major technology corporations. The focus of the reports was on major threat actors and their attacks against the corporations and their clients. The data were organized chronologically by year, and prevalent or abnormal findings were shared in this report. It was found that social engineering attacks were tremendously effective. Many ransomware attacks stemmed from Phishing. Social engineering approaches allowed attackers to conduct breaches using ransomware applications like GandCrab and Ryuk. Humans are incredibly susceptible and fall for social engineering tactics- primarily …

Corporate Cybersecurity In The Context Of M&A Transactions, Cameron Beck

Cybersecurity Undergraduate Research Showcase

The rapid rise of digital devices has unlocked a new dimension of innovation and prosperity in the 21st century. Computers are now an integrated and ubiquitous part of our global culture. You would be hard-pressed to walk into any given room without several computer chips humming inaudibly inside the machines that facilitate our modern world. Even lightbulbs and doorbells are connected to the Internet, capturing information from the world around them and sending that information to the Cloud. The Internet expands access to communication, international marketplaces, entertainment, professional resources, and nearly every book in the world.

Random Password Generation, Kirk Smith

Cybersecurity Undergraduate Research Showcase

This paper will discuss the topic of random generation, first by explaining the topic, followed by how the literature review was performed. Then, a literature review will be performed, followed by a discussion of human biases and the strength of random password generation.

The Future Of Blockchain, Elijah N. Gartrell

Cybersecurity Undergraduate Research Showcase

Blockchain is the leading technology for cryptocurrencies, NFT’s and other online marketplace transactions that go through it because of it’s secure technology and how they distribute their data with Smart Contracts. This report shows how we can use Blockchain for other uses in our world and how it could advance us in the cybersecurity aspects. Showing also why we should use blockchain with basic cybersecurity concerns as in: Malware Detection, Voter Fraud, and Medical Record Security.

Increased Caribbean Seismicity And Volcanism During Minima In Earth's Rotation Rate: Search For A Physical Mechanism And A 2030 Forecast, Roger Bilham, Walter Szeliga, David Mencin, Rebecca Bendick

Geological Sciences Faculty Scholarship

Three quarters of all Mw ≥ 6.6 earthquakes and volcanic eruptions surrounding the Caribbean plate occur preferentially during periods of decadal minima in Earth’s angular spin velocity. This correlation is revealed most clearly as a 4–6 years phase lag following the first derivative of the length of the day (LOD), Earth’s angular deceleration. We show that local strains and displacements resulting from oblateness changes, or plate boundary stresses associated with changes in tropical rotation rates are orders of magnitude lower than those typically associated with earthquake or volcano triggering. Notwithstanding the absence of a satisfactory causal physical mechanism, the relationship …

Cryogenic Magnetic Field Monitoring System In The Sns Neutron Edm Experiment, Umit Hasan Coskun

Theses and Dissertations--Physics and Astronomy

A permanent neutron electric dipole moment (nEDM), d_n, would violate charge-conjugation and parity (CP) symmetry. The neutron electric dipole moment currently has a global limit of d_n < 1.8 x 10^-26 e cm (90% CL). This limit is intended to be improved by two orders of magnitude by the nEDM experiment at the Spallation Neutron Source (SNS nEDM), d_n ~ 10^-28 e cm. The magnetic field non-uniformities within the experimental region must be precisely monitored and managed in order to suppress systematic effects in the experiment caused by magnetic field gradients. The estimation of magnetic field components within …

The “Office Of The Ciso”: A Framework For Chief Information Security Officers, Yael Nagler, Christophe Veltsos

Computer Information Science Department Publications

As we enter 2022, cybersecurity continues to challenge corporations and their CISOs. The sophistication of cyberthreats coupled with an evolving digital landscape has resulted in increased complexity and expanded responsibilities for the CISO. Simply put, there is greater scrutiny, greater regulation, greater complexity, and greater scope than ever before. To respond to these changes, CISOs must organize their “Office of the CISO” to meet the expectations and deliver for their organizations. Whether the CISO has a staff of three or thirty and whether they are prepared or not, these elements are being increasingly expected of CISOs. You can think of …

Reconstructing Regional Paleoenvironments And Geomorphic History Of High Plains Playa-Lunette Systems, Alyssa E. Sims

All Graduate Theses, Dissertations, and Other Capstone Projects

Playas are ephemeral upland-embedded wetlands found in semiarid and arid regions worldwide. Lunettes are isolated dunes that form along the downwind margin of playas. The paleoclimatic and geomorphic history of High Plains playa-lunette systems (PLSs) are poorly understood. To address this, we characterize the stratigraphy of four PLSs in southwest Kansas, USA. Methods include: 1) collect soil-sediment cores from playa centers and windward slopes of lunettes; 2) describe cores using USDA techniques; 3) estimate age of stratigraphic units using radiocarbon (14C); and 4) reconstruct paleoenvironmental conditions using stable carbon isotopes (13C) and particle size analysis. Playa stratigraphy is relatively simple …

Jet Substructure Measurements In Proton-Proton And Proton-Gold Collisions, Isaac Arthur Mooney

Wayne State University Dissertations

Observing a modification of high-energy probes in the hot nuclear environment created by ultrarelativistic heavy-ion collisions is critical for understanding the microscopic structure of the QCD medium. However, before a modification can be observed, the probes must be calibrated. For this reason, measurements of jet observables in vacuum (pp collisions) and in the presence of cold nuclear matter (pAu collisions) are presented, which will allow for future comparison of jet substructure measurements in AuAu to these baseline measurements. \parData from the STAR detector on the Relativistic Heavy Ion Collider at Brookhaven National Laboratory are used for both analyses. The pp …

Academy Presidents And Institutional Members, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

Table Of Contents, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

Seasonal Testicular Histology And Acystic Lobular Spermatogenesis In The Western Lesser Siren, Siren Intermedia Nettingi (Caudata: Sirenidae), Stanley E. Trauth

Journal of the Arkansas Academy of Science

I investigated the seasonal testicular histology and acystic lobular spermatogenesis in the Western Lesser Siren, Siren intermedia nettingi, from periodic sampling of this salamander over a span of 21 yr (1994-2015) in northeastern Arkansas. My results include the following general findings: 1) the largest testicular lobules occurred primarily in January-February during spermiogenesis and spermatozoa maturation; 2) lobular regression and spermatogenic cell recrudescence were underway by late March; 3) proliferation of secondary spermatogonia in lobules was prominent in May; 4) transformation of secondary spermatogonia into primary spermatocytes occurred by mid-July, and these cells became larger in diameter through increased nuclear …

A New Non-Inheriting Homogeneous Solution Of The Einstein-Maxwell Equations With Cosmological Term, Ian M. Anderson, Charles G. Torre

Publications

We find a new homogeneous solution to the Einstein-Maxwell equations with a cos- mological term. The spacetime manifold is R × S3. The spacetime metric admits a simply transitive isometry group G = R × SU(2) and is Petrov type I. The spacetime is geodesically complete and globally hyperbolic. The electromagnetic field is non- null and non-inheriting: it is only invariant with respect to the SU(2) subgroup and is time-dependent in a stationary reference frame.

Analysis Of Sex-Specific Prostanoid Production Using A Mouse Model Of Selective Cyclooxygenase-2 Inhibition, Rita K. Upmacis, Wendy L. Becker, Donna M. Rattendi, Raven S. Bell, Kelsey D. Jordan, Shayan Saniei, Elena Mejia

Faculty Papers and Publications

Background: Prostanoids are a family of lipid mediators formed from arachidonic acid by cyclooxygenase enzymes and serve as biomarkers of vascular function. Prostanoid production may be different in males and females indicating that different therapeutic approaches may be required during disease.

Objecti ves: We examined sex-dependent differences in COX-related metabolites in genetically modified mice that produce a cyclooxygenase- 2 (COX2) enzyme containing a tyrosine 385 to phenylalanine (Y385F) mutation. This mutation renders the COX2 enzyme unable to form a key intermediate radical required for complete arachidonic acid metabolism and provides a model of selective COX2 inhibition.

Design and …

Production Of Nimn2o4 Hollow Spheres And Cofe2o4 Bowl-Like Structures By Using Block Copolymer Stabilized Polystyrene Spheres As A Hard Template, Gökhan Koçak, Vural Bütün

Turkish Journal of Chemistry

The aim of this study is to highlight the use of polystyrene (PS) latexes stabilized with block copolymers as a hard template in the production of metal oxide hollow spheres. PS latexes produced by dispersion polymerization by stabilizing with tertiary amine methacrylate-based diblock copolymer were used as a hard template in the preparation of nickel manganese oxide (NiMn2O4) hollow spheres and cobalt iron oxide (CoFe2O4) bowl-like structures. Thanks to the diblock copolymer stabilizer with tertiary amine functional groups on the PS surface, precursor salts of CoFe2O4 and NiMn2O4 were first homogeneously deposited on the surface of PS latexes with a …

Preparation Of Surface Plasmon Resonance-Based Nanosensor For Curcumin Detection, Şebnem Çikrik, Duygu Çi̇men, Ni̇lay Bereli̇ Deni̇zli̇, Adi̇l Deni̇zli̇

Turkish Journal of Chemistry

In this study, the curcumin imprinted and the non-imprinted poly(2-hydroxyethyl methacrylate-N-methacryloyl-Ltryptophan) (poly(HEMA-MATrp)) nanoparticle based surface plasmon resonance (SPR) nanosensors were prepared for the detection of curcumin and characterized by zeta-size analysis, Fourier transform infrared spectroscopy, and scanning electron microscopy. After, the curcumin imprinted and the non-imprinted nanoparticles are attached on the surface of SPR chips. The curcumin imprinted and the non-imprinted SPR nanosensors are characterized by using atomic force microscope, ellipsometer, and contact angle measurements. Kinetic studies were carried out with curcumin aqueous solution at a concentration range of 0.01-150 mg/L using the curcumin imprinted and the non-imprinted SPR nanosensors. …

Solar Light Degradation Of Organic Dye Pollutants And Preparation Of Bis(Indolyl)Methanes Using Core-Shell Fe3o4@Sio2@Cuo Nanocomposite, Kaveh Parvanak Boroujen, Zeinab Tohidiyan, Mina Mirzaei

Turkish Journal of Chemistry

In this research, a new ferromagnetic-recoverable core-shell Fe3O4@SiO2@CuO nanocomposite of a certain size (20-25 nm) has been synthesized based on Cu(II) complex coated on Fe3O4@SiO2@CuO nanoparticles by facile and fast solid state microwave irradiation method. The photocatalytic activity of the nanocomposite was investigated for degradation of methylene blue (MB) and methyl orange (MO) dye pollutants in aqueous media under solar light irradiation. The nanocomposite could destroy these dyes with high efficiency in short time. With comparison of degradation percentages can be concluded that the nanocomposite shows better photocatalytic activity for MB dye (97% in 180 s). Kinetic study revealed higher …

Synthesis Of Modified Nanocomposite Material And Its Use On Removal Of Cesium Fromaqueous Media, Bi̇lal Çeti̇n, Mustafa Özcan, Bektaş Karakelle

Turkish Journal of Chemistry

A nanocomposite containing Fe3O4, chitosan (Ch), and hexacyanoferrate (HCF) was synthesized in the form of powder. The physicochemical properties of this nanocomposite are determined using different techniques including Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM). The existence of Cs (Cs) ions onto the surface of the nanocomposite was verified by dispersive X-ray spectroscopy (EDX). FTIR spectra confirmed that the nanocomposite was well coordinated. The batch technique was applied to evaluate the influences of initial pH value, temperature, contact time, shaking rate, initial Cs concentration, and competing cations on the efficiency of Cs …

The Study Of Fe3o4@Sio2-Nh2 Nano-Magnetic Composite Modified By Glutaraldehyde To Immobilized Penicillin G Acylase, Monier Alhadi Abdelrahman Mohammed, Zhenbin Chen, Ke Li, Boyuan Zhang

Turkish Journal of Chemistry

Preparation of biocatalyst dependent on immobilized penicillin G acylase (PGA) was of substantial importance for proteomic research, organic synthesis, and industrial applications. Herein, we developed an easy method for nano-magnetic composite to immobilize PGA. Fe3O4 nano-magnetic particles were co-precipitated with Fe3+ and Fe2+ in an ammonia solution (NH3) and treated with silicon dioxide (SiO2), which was developed using the sol-gel process. Thereafter, 3-aminopropyltriethoxysilane (APTES) was used to modify the silica-coated Fe3O4, which would result in the attachment of the primary amine groups to the particle surface. After that, the attachment of primary amine group was reacted with glutaraldehyde (Glu) to …

Synthesis, Molecular Modeling, And Biological Evaluation Of Novel Imatinib Derivatives Asanticancer Agents, Fulya Günay, Sevcan Balta, Yuk Yin Ng, Özlem Ulucan Açan, Zühal Turgut, Ömer Tahi̇r Günkara

Turkish Journal of Chemistry

Different derivatives of imatinib were synthesized by a 3-step reaction method. The structures of the new compounds were characterized by spectroscopic methods. For quantitative evaluation of the biological activity of the compounds, MTT assays were performed, where four BCR-ABL negative leukemic cell lines (Jurkat, Reh, Nalm-6 and Molt-4), one BCR-ABL positive cell line (K562), and one non-leukemic cell line (Hek293T) were incubated with various concentrations of the derivatives. Although imatinib was specifically designed for the BCR-ABL protein, our results showed that it was also effective on BCR-ABL negative cell lines except for Reh cell line. Compound 9 showed lowest IC50 …