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Articles 991 - 1020 of 33925

Full-Text Articles in Physics

Enhancement Of Phenolic, Flavonoid, And Biological Activi-Ties In Fermented Pea (Pisum Sativum) Extracts Via Frac-Tionation, Anastasia Fitria Devi, Euis Filailla, Setyani Budiari, Hani Mulyani, Nina Artanti Jun 2025

Enhancement Of Phenolic, Flavonoid, And Biological Activi-Ties In Fermented Pea (Pisum Sativum) Extracts Via Frac-Tionation, Anastasia Fitria Devi, Euis Filailla, Setyani Budiari, Hani Mulyani, Nina Artanti

Karbala International Journal of Modern Science

In this study, peas were fermented for 24 h using either Rhizopus oligosporus or Aspergillus oryzae. The resulting fermented peas, along with unfermented peas, were extracted using either methanol or water. The methanol extracts showed greater improvements following fermentation compared to the water extracts, as shown by the IC50 values, which progressed from >500 to ≤200 µg/mL, as determined via the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) method. Consequently, further fractionations focused on the methanol extracts of the fermented peas. Six bands were resolved on thin-layer chromatography plates for each extract. Their positions demonstrated significant effects (p < 0.05) on bioactivity. The bottom band (i.e., Band 1) exhibited approximately 70% inhibition, as determined via the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method and 35% inhibition according to the ABTS method, while the other bands displayed lower to negligible inhibition. Band 5 displayed 85–97% cytotoxicity, while Band 1 did not show any cytotoxicity. The total phenolic content (TPC) of Band 1 and the total flavonoid content (TFC) of Band 6 increased 4.4- and 8.9-fold, respectively, compared to those of the unfractionated extracts. Furthermore, a correlation analysis revealed a strong correlation between TFC and the three observed bioactivities. The different cultures significantly (p < 0.05) affected the antioxidant activity of either the fermented pea extracts or the resulting bands, as determined via the DPPH method. These results indicated that fermentation enhanced the antioxidant activity of peas. Subsequent fractionations separated and concentrated compounds from the fermented peas, improving the bioactivities, TPC, and TFC of the resulting fractions.


Synthesis Of Gold Nanoparticles Using Hordeum Vulgare Leaf Extract And Their Antibacterial Activity, Mohamed M. Sehree, Shakir Ghazi Gergees, Pakhshan A. Hassan Jun 2025

Synthesis Of Gold Nanoparticles Using Hordeum Vulgare Leaf Extract And Their Antibacterial Activity, Mohamed M. Sehree, Shakir Ghazi Gergees, Pakhshan A. Hassan

Karbala International Journal of Modern Science

Plant extracts and gold nanoparticles are promising alternatives for combating antibiotic resistance in light of the increasing bacterial resistance. Leaf extract of barley was used to synthesize gold nanoparticles (AuNPs). Barley gold nanoparticles (BL-AuNPs) were produced by adjusting some reaction parameters. These BL-AuNPs were characterized through employing the UV-visible spectroscopy technique, the scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), and energy dispersive X-ray spectroscopy (EDX). BL-AuNPs were tested for antibacterial efficacy against two strains of Gram-negative bacteria, clinically isolated and considered as multidrug-resistant pathogens, Acinetobacter baumannii and Salmonella typhi. The antimicrobial efficiency of the compounds was evaluated …


The Impact Of Microplastics On Water Quality, Heavy Metals, And Health Risks In Bioflocbased Tilapia Farming Systems, Dian Rizky Afriani, Deswati Deswati, Rahmiana Zein, Putri Ramadhani Jun 2025

The Impact Of Microplastics On Water Quality, Heavy Metals, And Health Risks In Bioflocbased Tilapia Farming Systems, Dian Rizky Afriani, Deswati Deswati, Rahmiana Zein, Putri Ramadhani

Karbala International Journal of Modern Science

Along with microplastics, pollution of heavy metals, including iron (Fe), zinc (Zn), and copper (Cu), in freshwater ecosystems poses a serious environmental threat that can adversely affect human health. This study investigates the use of biofloc technology to reduce microplastic and heavy metal contamination while improving water quality. By utilizing microbial aggregates that capture microplastic and heavy metal particles through flocculation and biosorption processes, four experimental treatments were applied, i.e.: A (without biofloc and microplastics); B (with biofloc, without microplastics); C (with biofloc and low-density polyethylene microplastics); and D (with biofloc and high-density polyethylene microplastics). The results indicate that fish …


Evolution Of Wormholes Under F(R, T) Theory, The Karmarkar Condition And The Casimir Energy, Murat Metehan Türkoğlu Jun 2025

Evolution Of Wormholes Under F(R, T) Theory, The Karmarkar Condition And The Casimir Energy, Murat Metehan Türkoğlu

Turkish Journal of Physics

In this study, both the evolution of wormholes (by examining both the energy conditions and using the TOV equations) and the effects of the Karmarkar condition on the solutions obtained under certain specific cases were examined in the light of the f(R, T) gravity theory, using two f(R, T) functions predicted to describe the accelerated expansion of the universe. In this context, for the first time in the literature, a generalized shape function was obtained using the Karmarkar condition. It was observed that solutions of the type R -a12/R+a2g(T) satisfy the energy conditions (with the dominant energy condition being partially …


Circular Motion And Thermodynamic Characteristics Of Particles Around A Quintessential Nonrotating Black Hole, Indrajit Halder, Kamal Lochan Mahanta, Rakesh Ranjan Sahoo Jun 2025

Circular Motion And Thermodynamic Characteristics Of Particles Around A Quintessential Nonrotating Black Hole, Indrajit Halder, Kamal Lochan Mahanta, Rakesh Ranjan Sahoo

Turkish Journal of Physics

This paper investigates the geodesics of the Schwarzschild black hole modified with the quintessence field and modeled as a barotropic fluid with a constant equation of state derived in Boyer Lindquist coordinates with natural units G = c = 1. Hamilton–Jacobi formalization is applied to investigate the geodesics in both static and nonstatic black hole spacetime. It specifically examines the formation of bound orbits of test particles around the black hole, highlighting that these orbits result from the interplay between the gravitational pull of the black hole and a repulsive force associated with quintessence. The thermodynamic properties of a black …


Enhanced Crack Resistance Of Porous Anodic Aluminum Oxide Grown On A Tubular Substrate With The Additive Ethylene Glycol, Manogari Sianturi, Ariadne Laksmidevi Juwono, Anawati Anawati Jun 2025

Enhanced Crack Resistance Of Porous Anodic Aluminum Oxide Grown On A Tubular Substrate With The Additive Ethylene Glycol, Manogari Sianturi, Ariadne Laksmidevi Juwono, Anawati Anawati

Makara Journal of Science

The growth of a porous anodic aluminum oxide (PAAO) layer with fewer cracks on a tubular substrate is quite challenging. The PAAO layer on a curved surface grows slower than that on a flat surface and is susceptible to cracking. This study aims to improve the crack resistance of the PAAO layer grown on a tubular aluminum substrate by adding ethylene glycol (EG). Each bath contained additive concentrations of 0, 5, 10, and 15 vol% EG. Anodization proceeded for 4 h at a temperature of 10 ℃ using the potentiostatic mode at 25 V in a sulfuric acid bath and …


Parity-Time Symmetry In Vcsels Utilizing Lithographic Cavities, Abdullah Demi̇r Jun 2025

Parity-Time Symmetry In Vcsels Utilizing Lithographic Cavities, Abdullah Demi̇r

Turkish Journal of Physics

Parity-time symmetry (PTS) has emerged as a powerful strategy for engineering single-mode lasers with enhanced mode selectivity. In this work, we present a systematic numerical study comparing two classes of non-Hermitian micro-laser designs: PTS and quasi-PTS (q-PTS). Using lithographically defined vertical-cavity surface-emitting lasers (Li-VCSELs) as our platform, we show that q-PTS VCSELs offer superior transverse mode discrimination compared to their PTS counterparts. This advantage arises from the unique coupling mechanism in q-PTS architectures, where the fundamental mode preserves its low-loss nature. In contrast, PTS VCSELs require the second-order mode to remain in the PTS phase while the fundamental mode is …


Variational Monte Carlo Optimization Of Proton-Proton Scattering Potential Using The Phase Function Method, Shikha Awasthi, Anil Khachi, O.S.K.S. Sastri Jun 2025

Variational Monte Carlo Optimization Of Proton-Proton Scattering Potential Using The Phase Function Method, Shikha Awasthi, Anil Khachi, O.S.K.S. Sastri

Turkish Journal of Physics

The Riccati-type nonlinear differential equation, also known as the Phase Function equation, is used to construct local inverse potentials for the 1S0 - pp state by bypassing the well-known Schrödinger equation. The pp interaction is described using the Malfliet-Tjon potential model for the nuclear component combined with a screened Coulomb potential, with the phase equation solved via the fourth-order Runge-Kutta (RK-4) method. Based on our analysis, we confirm that the optimized interaction potential closely matches the well-known realistic Argonne V18 and Reid potentials for the 1S0 state, and the computed phase shifts and cross-sections show excellent agreement with experimental data. …


Physical And Chemical Characterization Of Recycled Glass Sand For Environmental Restoration, Shehbaz Ahmad, Julie P. Vanegas, Nicholas Borne, Natalia Butler, Toby Mendels, Leah A. Michaeloff, Diego Molina, Mary Salvaggio, Samantha Tamayo, Franziska Trautmann Jun 2025

Physical And Chemical Characterization Of Recycled Glass Sand For Environmental Restoration, Shehbaz Ahmad, Julie P. Vanegas, Nicholas Borne, Natalia Butler, Toby Mendels, Leah A. Michaeloff, Diego Molina, Mary Salvaggio, Samantha Tamayo, Franziska Trautmann

Physics & Astronomy Faculty Publications

Introduction

We rely on coastal resources for food, water, and energy. However, over 75% of U.S. coastlines are eroding. Concurrently, the U.S. recycles less glass than other developed countries, landfilling hundreds of millions of tons every year. Recycled glass sand has many potential benefits over natural sand for combatting land loss; for example, it can be produced with controlled particle size to better resist erosion, making it an excellent—and underutilized—material for environmental restoration.

Objectives

This research compares the physical and chemical properties of recycled glass sand to natural sands (beach and dredge) from the U.S. Gulf Coast to assess environmental …


The Nanograv 15 Yr Data Set: Search For Gravitational-Wave Memory, Gabriella Agazie, Akash Anumarlapudi, Anne M. Archibald, Zaven Arzoumanian, Jeremy G. Baier, Paul T. Baker, Bence Bécsy, Laura Blecha, Adam Brazier, Paul R. Brook, Sarah Burke-Spolaor, Rand Burnette, J. Andrew Casey-Clyde, Maria Charisi, Shami Chatterjee, Tyler Cohen, James M. Cordes, Neil J. Cornish, Fronefield Crawford, H. Thankful Cromartie, Kathryn Crowter Jun 2025

The Nanograv 15 Yr Data Set: Search For Gravitational-Wave Memory, Gabriella Agazie, Akash Anumarlapudi, Anne M. Archibald, Zaven Arzoumanian, Jeremy G. Baier, Paul T. Baker, Bence Bécsy, Laura Blecha, Adam Brazier, Paul R. Brook, Sarah Burke-Spolaor, Rand Burnette, J. Andrew Casey-Clyde, Maria Charisi, Shami Chatterjee, Tyler Cohen, James M. Cordes, Neil J. Cornish, Fronefield Crawford, H. Thankful Cromartie, Kathryn Crowter

Pacific Faculty Work

We present the results of a search for nonlinear gravitational-wave (GW) memory in the NANOGrav 15 yr data set. We find no significant evidence for memory signals in the data set, with a maximum Bayes factor of 3.1 in favor of a model including memory. We therefore place upper limits on the strain of potential GW memory events as a function of sky location and observing epoch. We find upper limits that are not always more constraining than previous NANOGrav results. We show that it is likely due to the increase in common red noise between the 12.5 and 15 …


Yb:Ylf Optical Cryocoolers: Saturation Effects, Pump Management, Robust Thermometry, And Novel Architectures, Jackson Kock Jun 2025

Yb:Ylf Optical Cryocoolers: Saturation Effects, Pump Management, Robust Thermometry, And Novel Architectures, Jackson Kock

Optical Science and Engineering ETDs

Solid-state optical refrigeration using anti-Stokes fluorescence offers a compact, vibration-free route to cryogenic cooling. This dissertation advances ytterbium-doped yttrium lithium fluoride (Yb:YLF) refrigerators, achieving a world record payload cooling temperature of 124 K by addressing key limitations due to absorption saturation. An expanded theoretical model incorporating saturation effects enables accurate predictions of cooling performance under high pump intensities. To improve pump control, a modeling framework for astigmatic Herriott cells was developed, revealing how beam clipping and intensity impact coupling efficiency. A novel fluorescence-based thermometry method was also established, providing accurate, orientation-independent temperature sensing by overcoming reabsorption and crystal orientation. Finally, …


Generation Of Non-Maxwell-Boltzmann Energy Distributions During Thermalization Of Interacting Baths, Roberto Onofrio, Bala Sundaram Jun 2025

Generation Of Non-Maxwell-Boltzmann Energy Distributions During Thermalization Of Interacting Baths, Roberto Onofrio, Bala Sundaram

Data and Datasets

data associated with all the figures in the publication.


Development Of A Near Terahertz Backward Wave Oscillator Using Standard Waveguide, Alexander Glick Jun 2025

Development Of A Near Terahertz Backward Wave Oscillator Using Standard Waveguide, Alexander Glick

Electrical and Computer Engineering ETDs

There is a demand for terahertz (THz) frequency radiation sources. Applications include, but are not limited to, imaging for medical and security purposes, biochemical and organic spectroscopy, and velocimetry. Historically, there was a limited supply of THz devices due to technological limitations. In recent years much progress has been made to reduce this “gap” in supply and demand for THz sources. This work proposes a vacuum electronic device that produces high power, extremely high frequency radiation in the G-band, by utilizing a backward wave oscillator (BWO) based on WR3 standard waveguide. This device is compact, fundamentally simple, and has great …


2d Cuo/Rgo Nanocomposite: A Novel Architecture For Enhanced Cr(Vi) Photo-Reduction, Islam Gomaa, Nasser M. Hosny, Medhat A. Ibrahim Jun 2025

2d Cuo/Rgo Nanocomposite: A Novel Architecture For Enhanced Cr(Vi) Photo-Reduction, Islam Gomaa, Nasser M. Hosny, Medhat A. Ibrahim

Nanotechnology Research Centre

he urgent need for efficient detoxification of carcinogenic hexavalent chromium (Cr(VI)) in aquatic environments has driven the development of advanced photocatalytic materials. This study presents the synthesis of 2D CuO/reduced graphene oxide (rGO) nanocomposite via probe sonication, designed to synergistically enhance the photocatalytic reduction of Cr(VI) to less toxic Cr(III). The nanocomposite was meticulously characterized using XRD, HRTEM, FESEM, XPS, and UV-Vis diffuse reflectance spectroscopy. Structural analysis confirmed the formation of CuO nanosheets (average size: 396 nm, thickness: 6 nm) integrated with rGO, where the rGO acted as an electron acceptor, mitigating charge recombination. XPS revealed Cu²⁺ in CuO and …


Exploring The Very Early Cosmological History With Dark Matter And Primordial Black Holes, Phuc Duc Loc Ngo Jun 2025

Exploring The Very Early Cosmological History With Dark Matter And Primordial Black Holes, Phuc Duc Loc Ngo

Physics & Astronomy ETDs

We explore the possibilities of nonstandard early cosmological histories and their potential roles to explain DM. We study how particle DM is produced with scenarios of early matter domination (EMD), how primordial black holes (PBHs), which could also be a DM candidate in certain mass ranges, are formed with enhanced curvature perturbation or FOPT and the corresponding gravitational wave (GW) signals, how PBHs could increase their mass by accretion during EMD and the corresponding GW signals.


Uncovering Multiscale Structure-Property Correlations Via Active Learning In Scanning Tunneling Microscopy, Ganesh Narasimha, Deja Kong, Paras Regmi, Rongying Jin, Zheng Gai, Rama Vasudevan, Maxim Ziatdinov Jun 2025

Uncovering Multiscale Structure-Property Correlations Via Active Learning In Scanning Tunneling Microscopy, Ganesh Narasimha, Deja Kong, Paras Regmi, Rongying Jin, Zheng Gai, Rama Vasudevan, Maxim Ziatdinov

Faculty Publications

Atomic arrangements and local sub-structures fundamentally influence emergent material functionalities. These structures are conventionally probed using spatially resolved studies and the property correlations are deciphered by a researcher based on sequential explorations, thereby limiting the efficiency and scope. Here we demonstrate a multi-scale Bayesian deep-learning based framework that automatically correlates material structure with its electronic properties using scanning tunneling microscopy (STM) measurements in real-time. Its predictions are used to autonomously direct exploration toward regions of the sample that optimize a given material property. This method is deployed on a low-temperature ultra-high vacuum STM to understand the structure-property relationship in a …


The Thermodynamic Fate Of Isolated Quantum Systems, John Keim, Isabel Martinez-Robles, Nicolaus A. Chlanda, Sage M. Thomas, Maja Teofilovska, Sarah E. Spielman, Jordyn Strunk, Tina Zhao, Juniper J. Bauroth-Sherman, Hannah Conley, Philip Conte, Aidan Kirk, Thomas J. Carroll, Michael W. Noel Jun 2025

The Thermodynamic Fate Of Isolated Quantum Systems, John Keim, Isabel Martinez-Robles, Nicolaus A. Chlanda, Sage M. Thomas, Maja Teofilovska, Sarah E. Spielman, Jordyn Strunk, Tina Zhao, Juniper J. Bauroth-Sherman, Hannah Conley, Philip Conte, Aidan Kirk, Thomas J. Carroll, Michael W. Noel

Physics and Astronomy Summer Fellows

Isolated quantum systems are typically observed to come to thermal equilibrium. The weak Eigenstate Thermalization Hypothesis (wETH) states that the vast majority of eigenvectors are thermal. This implies that most initial states should thermalize. Studying the rare cases in which they fail to thermalize could reveal insight into quantum dynamics. In our experiment, we excite Rydberg atoms and allow them to exchange energy via dipole-dipole interactions. We find that they do not thermalize. We present numerical and theoretical results that show that our experimental initial state is not typical.


Investigation Of Isobaric Mixing As A Mechanism For Boundary-Layer Cloud Formation, Jaemin Yeom, Nithin Allwayin, Virendra P. Ghate, Katia Lamer, Fan Mei, Raymond A. Shaw Jun 2025

Investigation Of Isobaric Mixing As A Mechanism For Boundary-Layer Cloud Formation, Jaemin Yeom, Nithin Allwayin, Virendra P. Ghate, Katia Lamer, Fan Mei, Raymond A. Shaw

Michigan Tech Publications

This study investigates the potential role of isobaric mixing in the formation of marine boundary layer clouds. Cloud formation theory emphasizes uplift and adiabatic cooling, but recent observations support the existence of small clouds forming at various altitudes, even below the lifting condensation level. Isobaric mixing of air with different thermodynamic properties can generate localized supersaturation. A Gaussian mixing model is employed to simulate this process, considering the correlation between temperature and water vapor. Cloud droplet size distributions from aircraft measurements show a persistent and prominent mode of small droplets at 9 (Formula presented.) m, and the size of this …


Deep Neural Networks For Particle Identification In Simulated Proton-Proton Collisions At Lhc And Rhic, Omar Mazhar Khalaf Jun 2025

Deep Neural Networks For Particle Identification In Simulated Proton-Proton Collisions At Lhc And Rhic, Omar Mazhar Khalaf

Theses and Dissertations

Particle identification is an essential part of experimental high-energy physics, which allows the study of the most fundamental constituents of matter. This thesis explores the use of deep neural networks for identifying particles in simulated proton-proton collisions at the Large Hadron Collider (LHC) and the Relativistic Heavy Ion Collider (RHIC). The deep neural networks were trained on LHC datasets which have various momentum ranges including regions of high transverse momentum above 3 GeV/c. The key findings of thesis include achieving an accuracy of 99.99%, 98.3%, and 90.14% for 3-5 pt, 5-7 pt and above 7 pt regions respectively for the …


Hydrogen Storage In Multilayer Ti3c2tx Mxene, Yi Zhi Chu, Kah Chun Lau Jun 2025

Hydrogen Storage In Multilayer Ti3c2tx Mxene, Yi Zhi Chu, Kah Chun Lau

Michigan Tech Publications

In this work, we systematically investigated the hydrogen storage properties of multilayer Ti3C2Tx MXene using density functional theory (DFT) coupled with the quantum-thermodynamic model to include the thermodynamic effect on hydrogen adsorption and storage behavior over a wide range of applied pressure and temperature. In addition to the surface-adsorbed hydrogen, we show that the interlayer spacing is a plausible storage route that could contribute to an additional hydrogen storage capacity. Due to hydrogen-bond bounded multilayer Ti3C2Tx, the insertion, diffusion, and adsorption of hydrogen molecules into the interlayer spacing of the multilayer structure require sufficient external pressure to overcome the energy …


Basic Theory And Implementations Of Quantum Error Correction, Derek Rodriguez Jun 2025

Basic Theory And Implementations Of Quantum Error Correction, Derek Rodriguez

Undergraduate Theses, Capstones, and Recitals

The introduction of quantum computing has presented algorithmic solutions to computationally difficult challenges that are far more efficient than those of classical computers. These algorithms leverage the properties of quantum mechanics to manipulate the quantum properties of subatomic particles, requiring immense precision and stability. Current quantum hardware, however, is too noisy and introduces too many errors for these algorithms to be useful in practice, necessitating the use of error correction algorithms. This field survey seeks to introduce various principles of quantum mechanics relevant to quantum computing and quantum error correction (QEC), detail the implementation and motivations of a basic QEC …


The Spectral Response Of Time-Resolved Piv In A Turbulent Boundary Layer, Peter Manovski, Wagih Abu Rowin, Henry Ng, Paul Gulotta, Matteo Giacobello, Charitha De Silva, Nicholas Hutchins, Ivan Marusic Jun 2025

The Spectral Response Of Time-Resolved Piv In A Turbulent Boundary Layer, Peter Manovski, Wagih Abu Rowin, Henry Ng, Paul Gulotta, Matteo Giacobello, Charitha De Silva, Nicholas Hutchins, Ivan Marusic

Student Publications

This study presents the application of time-resolved particle image velocimetry (TR-PIV) to measure the mean and fluctuating velocity components in a turbulent boundary layer (TBL) over an axisymmetric body of revolution. A narrow wall-normal strip of the flow was captured using a synchronised high-speed laser and camera at a recording frequency of up to 80 kHz. The resulting streamwise and wall-normal velocity TR-PIV data were validated against hot-wire anemometry measurements and direct numerical simulations (DNS) of a flat plate under matched flow conditions. The mean flow results showed good agreement between all methods, while the expected attenuation due to the …


Shrinkage Study In Photopolymerisable Hybrid Sol-Gel Through Holographic Patterning, Jamshed Aftab, Izabela Naydenova, Tatsiana Mikulchyk Jun 2025

Shrinkage Study In Photopolymerisable Hybrid Sol-Gel Through Holographic Patterning, Jamshed Aftab, Izabela Naydenova, Tatsiana Mikulchyk

Articles

Photopolymerisation induced shrinkage of holographic materials is one of the main factors which needs to be considered for designing holographic optical elements (HOEs) with high accuracy in light redirection with maximum efficiency. This work studies the shrinkage in photopolymerisable hybrid sol-gel (PHSG) by examining the properties of volume transmission gratings recorded in PHSG layers. It explores both the dependence of shrinkage on the holographic grating parameters (thickness, spatial frequency, slant angle) and the effect of material aging. By using the fringe-plane rotation model, shrinkage is found to have the maximum value of 1.37 % at 765 lines/mm (19.36° slant angle) …


Composite Magnetic Monopoles, Moreshwar Pathak Jun 2025

Composite Magnetic Monopoles, Moreshwar Pathak

University Departments

No abstract provided.


Zeeman Effect Observations Of Water Masers In The Star Forming Region Ngc 7129 Firs2, Marina Bethann Beltran Jun 2025

Zeeman Effect Observations Of Water Masers In The Star Forming Region Ngc 7129 Firs2, Marina Bethann Beltran

College of Science and Health Theses and Dissertations

Magnetic fields likely play an important role in star formation, yet their influence remains poorly understood due to the observational challenges in measuring them. The only direct method for measuring magnetic fields is through the Zeeman effect, the splitting of spectral lines in the presence of a magnetic field. Water masers, which trace high-density shocked regions, are known to occur throughout some of the earliest stages of the star formation process. They provide an excellent opportunity to observe the Zeeman effect. However, Zeeman detections in H2O masers have so far been limited primarily to isolated, high-intensity maser lines with simple …


Theoretical Investigation On The Magnetic And Spintronic Behaviour Of 2d Mxenes, Abhinav Prashant Gotmare Jun 2025

Theoretical Investigation On The Magnetic And Spintronic Behaviour Of 2d Mxenes, Abhinav Prashant Gotmare

University Departments

No abstract provided.


Higher-Order Exceptional Points In A Non-Reciprocal Waveguide Beam Splitter, Hamed Ghaemidizicheh, Shahram Dehdashti, Andreas Hanke, Ahmed Touhami, Janis Nötzel Jun 2025

Higher-Order Exceptional Points In A Non-Reciprocal Waveguide Beam Splitter, Hamed Ghaemidizicheh, Shahram Dehdashti, Andreas Hanke, Ahmed Touhami, Janis Nötzel

Physics & Astronomy Faculty Publications

Non-Hermitian systems have attracted significant interest because of their intriguing properties, including exceptional points (EPs), where eigenvalues and the corresponding eigenstates coalesce. In particular, quantum systems with EPs exhibit an enhanced sensitivity to external perturbations, which increases with the order of the EP. Therefore, higher-order EPs hold significant potential for advanced sensing applications, but they are challenging to achieve due to stringent symmetry requirements. In this work, we study the dynamics of a generalized lossy waveguide beam splitter with asymmetric coupling by introducing non-reciprocity as a tunable parameter to achieve higher-order EPs even without dissipation. Moreover, we analyze the evolution …


The Rise Of Faint, Red Active Galactic Nuclei At Z > 4: A Sample Of Little Red Dots In The Jwst Extragalactic Legacy Fields, Dale D. Kocevski, Steven L. Finkelstein, Guillermo Barro, Anthony J. Taylor, Antonello Calabrò, Brivael Laloux, Johannes Buchner, Jonathan R. Trump, Gene C.K. Leung, Guang Yang, Mark Dickinson, Pablo G. Pérez-González, Fabio Pacucci, Kohei Inayoshi, Rachel S. Somerville, Elizabeth J. Mcgrath, Hollis B. Akins, Micaela B. Bagley, Rebecca A.A. Bowler, Laura Bisigello, Adam Carnall Jun 2025

The Rise Of Faint, Red Active Galactic Nuclei At Z > 4: A Sample Of Little Red Dots In The Jwst Extragalactic Legacy Fields, Dale D. Kocevski, Steven L. Finkelstein, Guillermo Barro, Anthony J. Taylor, Antonello Calabrò, Brivael Laloux, Johannes Buchner, Jonathan R. Trump, Gene C.K. Leung, Guang Yang, Mark Dickinson, Pablo G. Pérez-González, Fabio Pacucci, Kohei Inayoshi, Rachel S. Somerville, Elizabeth J. Mcgrath, Hollis B. Akins, Micaela B. Bagley, Rebecca A.A. Bowler, Laura Bisigello, Adam Carnall

Pacific Faculty Work

We present a sample of 341 “little red dots” (LRDs) spanning the redshift range z ∼ 2-11 using data from the CEERS, PRIMER, JADES, UNCOVER, and NGDEEP surveys. Unlike past use of color indices to identify LRDs, we employ continuum slope fitting using shifting bandpasses to sample the same rest-frame emission blueward and redward of the Balmer break. This enables the detection of LRDs over a wider redshift range and with less contamination from galaxies with strong breaks that otherwise lack a rising red continuum. The redshift distribution of our sample increases at z < 8 and then undergoes a rapid decline at z ∼ 4.5, which may tie the emergence of these sources to the inside-out growth that galaxies experience during this epoch. We find that LRDs are ∼1 dex more numerous than X-ray- and UV-selected active galactic nuclei (AGN) at z ∼ 5-7. Within our sample, we have identified the first two X-ray-detected LRDs. An X-ray spectral analysis confirms that these AGN are moderately obscured with log ( N H / cm 2 ) of 23 . 3 − 1.3 + 0.4 and 22.7 2 − 0.16 + 0.13 . Our analysis reveals that reddened AGN emission dominates their rest-optical light, while the rest-UV originates from their host galaxies. We also present NIRSpec observations from the RUBIES survey of 17 LRDs that show broad emission lines consistent with AGN activity. The confirmed AGN fraction of our sample is 71% for sources with F444W < 26.5. In addition, we find three LRDs with blueshifted Balmer absorption features in their spectra, suggesting an outflow of high-density, low-ionization gas from near the central engine of these faint, red AGN.


A Veblenian Approach To Chaos Theory, Isaiah Henry Jun 2025

A Veblenian Approach To Chaos Theory, Isaiah Henry

Hatfield Graduate Journal of Public Affairs

This paper provides a comparative analysis of Veblen's belief in disequilibrium, the field of chaos theory, and how these two frameworks connect. We explore the similarities and differences between Veblen's theories and the principles of chaos theory, including their shared emphasis on complexity and unpredictability. By analyzing the connections between Veblen's economic theories and chaos theory, we can gain a deeper understanding of the nature of disequilibrium and the complex forces that shape our world.


Effects Of Elevated Temperatures On Tooth Structure During Polymerization Of Composite Resin With A Variety Of Light Sources, Enas G. Yonis Jun 2025

Effects Of Elevated Temperatures On Tooth Structure During Polymerization Of Composite Resin With A Variety Of Light Sources, Enas G. Yonis

Al-Bahir

This study investigated the impact of high temperatures on dental tissues during the polymerization of optical fillings using a diode laser and two types of pulsed and continuous LED devices. Three distinct light source units were employed: a laser diode, an LEDition, and a LED.B. Temperature increases were measured at a distance of 1 mm from the thermocouple to the tip of the device. To create an experimental model, we fixed the operational voltage of the polymerization device and maintained a 1 mm gap between the terminal and the thermocouple wire. Temperature readings and thermal background (TO) measurements were taken …