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Analysis Of The Influence Of Anthropometric Dimensions Of Postural Ergonomics Using Multiple Linear Regression, Gashbeen Faisal Najmaddin, Edrees Muhammed Tahir Harki 2026 Physiotherapy Department, Technical Health and Medical College, Erbil Polytechnic University, 44001, Erbil- Kurdistan region, Iraq

Analysis Of The Influence Of Anthropometric Dimensions Of Postural Ergonomics Using Multiple Linear Regression, Gashbeen Faisal Najmaddin, Edrees Muhammed Tahir Harki

Al-Bahir

Ergonomics is the study of designing and arranging a workspace or product to optimize the “fit” between people and their work, ensuring safety, comfort, and efficiency. The scientific literature indicates that ergonomic perspectives on the workplace are connected to the anthropometrics of societies. This study primarily aims to create a model that integrates multiple predictive variables to estimate the target variable. Multiple linear regression analysis is used to identify how different anthropometric dimensions predict postural ergonomics during prolonged sitting. Based on the regression models’ results, the predicted can be calculated using user anthropometry and existing chair dimensions. Furthermore, the primary …


Dynamics Of Swimming Microorganisms At Structured Liquid Crystal Interfaces, Vajra Sabhapathy Badha 2026 University of Massachusetts Boston

Dynamics Of Swimming Microorganisms At Structured Liquid Crystal Interfaces, Vajra Sabhapathy Badha

Graduate Doctoral Dissertations

Active matter systems are self-driven units that consume energy to generate motion and mechanical stresses, producing non-equilibrium states of broad physical significance. Examples include synthetic microswimmers and migrating cells. Motile bacteria are a widely studied biological example because their self-propelled motion, hydrodynamic interactions, and collective organization are strongly coupled to local environmental conditions. Their swimming is sensitive to interfacial viscoelasticity, ordering, confinement, and hydrodynamic boundary effects, making them useful for investigating how interfaces regulate active biological motion. Because bacterial accumulation and attachment at interfaces are central to colonization and biofilm formation, these interactions are relevant to both active matter physics …


Microrheological Characterization Of Collagen-I Extracellular Matrix Remodeling During Tr146 Tumor Spheroid Invasion And Ppix-Mediated Photodynamic Therapy, Himantha Dilshan Saldonge 2026 University of Massachusetts Boston

Microrheological Characterization Of Collagen-I Extracellular Matrix Remodeling During Tr146 Tumor Spheroid Invasion And Ppix-Mediated Photodynamic Therapy, Himantha Dilshan Saldonge

Graduate Masters Theses

Oral squamous cell carcinoma (OSCC) invasion is strongly regulated by interactions between tumor cells and the surrounding extracellular matrix (ECM). However, localized ECM mechanical changes during tumor invasion and after photodynamic therapy (PDT) remain insufficiently understood. This study mainly investigated: time-dependent viscoelastic remodeling of collagen-I ECM during TR146 tumor cell invasion, visualization of time-dependent TR146 tumor cell invasion and post-PDT response using live/dead fluorescence imaging, and the direct effect of PpIX-mediated PDT on the viscoelastic properties of spheroid-free collagen-I ECM. Three-dimensional TR146 spheroids were generated using a non-adherent agarose-based method, surrounded by a basement-membrane-like Matrigel layer, and embedded in 3.0 …


Single Fluorogens And Orientation-Localization Microscopy For Quantifying Chemical And Biomolecular Dynamics At The Nanoscale, Yiyang Chen, Yuanxin Qiu, Matthew D. Lew 2026 Washington University in St. Louis

Single Fluorogens And Orientation-Localization Microscopy For Quantifying Chemical And Biomolecular Dynamics At The Nanoscale, Yiyang Chen, Yuanxin Qiu, Matthew D. Lew

Electrical & Systems Engineering Publications and Presentations

Many chemical systems look uniform only because ensemble measurements average over their most interesting molecules. Electron-transfer rates vary across electrode surfaces; lipid membranes contain nanodomains with distinct packing and fluidity; peptide aggregates exhibit local polymorphism; and biomolecular condensates contain transient networks of interactions that are blurred in ensemble images. A central challenge in chemical imaging is not simply to see smaller structures, but to measure chemical variables such as polarity, redox potential, and molecular confinement at the single-molecule level. In this Account, we describe how fluorogens, molecules whose brightness, blinking, spectral shifts, orientation, rotational mobility, and motion are directly shaped …


Ai-Driven Segmentation And Volumetric Response Modeling Of Liver Regions To Radiotherapy, Aashish Chandra Gupta 2026 The University of Texas MD Anderson Cancer Center UTHealth Houston Graduate School of Biomedical Sciences

Ai-Driven Segmentation And Volumetric Response Modeling Of Liver Regions To Radiotherapy, Aashish Chandra Gupta

Dissertations and Theses (Open Access)

In liver-directed radiotherapy (RT), liver regions receiving higher doses typically undergo atrophy while contralateral/adjacent lower-dose regions may exhibit compensatory hypertrophy through regeneration of healthy tissue. Optimizing the RT plan to promote regional hypertrophy while minimizing the risk of developing atrophy has the potential to enhance post-RT liver function and long-term survivorship. However, current clinical practice largely relies on global liver dose-volume metrics during RT-planning, which may obscure favorable dose-response correlation and limit actionable guidance for clinicians. Therefore, we hypothesized that post-RT regional liver response is governed by a combination of region-specific dose-volume and patient clinical features, and that these responses …


Multiscale Network Modeling Of Native And Modified Photosynthetic Light-Harvesting Complexes, Zane E. Armijo 2026 University of New Mexico

Multiscale Network Modeling Of Native And Modified Photosynthetic Light-Harvesting Complexes, Zane E. Armijo

Chemical and Biological Engineering ETDs

Photosynthetic light-harvesting complexes harvest solar energy and direct electronic excitations toward reaction centers with exceptional efficiency. This dissertation models the Fenna--Matthews--Olson complex of green sulfur bacteria, coupled to the PscA1 reaction center, as a chromophoric network. Forster resonance energy transfer theory, validated against numerically exact hierarchical equations of motion, was implemented in kinetic Monte Carlo simulations to resolve fine-grained excitation-transport pathways. The predicted charge-transfer efficiency of 77\% agrees with experiment, with the FMO2 monomer and its gateway pigment governing interfacial transfer. Systematic single, multi, and symmetry-preserving site removals, interpreted through Mobius inversion, identify critical pigments and show that cooperative effects …


Crystal Structural Analysis Of Medieval Human Bones Using Wide-Angle X-Ray Scattering, Selly Altangerel, Leslie Gracia 2026 DePaul University

Crystal Structural Analysis Of Medieval Human Bones Using Wide-Angle X-Ray Scattering, Selly Altangerel, Leslie Gracia

DePaul Discoveries

Female human second metacarpal (mc2) bones from a medieval cemetery at Wharram Percy, England, were studied using high-energy Wide-Angle X-ray Scattering (WAXS) at beamline 1-ID of the Advanced Photon Source at Argonne National Laboratory. The age-at-death of 33 samples was determined from molar wear and classified into 3 groups:  18-30, 30-50, and 50+ years old.  Rietveld refinements of the WAXS data were performed to obtain lattice parameters of the hexagonal carbonated apatite phase (cAp). Individual fittings for cAp peaks 00.2, 00.4, and 31.0 were performed to obtain their widths and correlate them to collagen retention. For the three samples described …


Monte Carlo Analysis Of Dose Distribution In Tumour And Adjacent Healthy Tissues During 192Ir Hdr Brachytherapy In The Presence Of Gold Nanoparticles, Damian P. Tippe, Innocent J. Lugendo 2026 Department of Physics, University of Dar es Salaam

Monte Carlo Analysis Of Dose Distribution In Tumour And Adjacent Healthy Tissues During 192Ir Hdr Brachytherapy In The Presence Of Gold Nanoparticles, Damian P. Tippe, Innocent J. Lugendo

Tanzania Journal of Science

High dose rate (HDR) brachytherapy using 192Ir is an effective modality for cancer treatment; however, its therapeutic efficiency is often constrained by unintended radiation exposure to healthy tissues surrounding the tumour. Fortunately, the incorporation of high atomic number (Z) nanoparticles as radiosensitizers has emerged as a promising strategy to enhance tumour dose while sparing adjacent normal tissues. In this study, the dose distribution in tumour and nearby healthy tissues during 192Ir HDR brachytherapy was investigated in the presence of gold (Au) nanoparticles using Monte Carlo simulations based on the Geant4 toolkit. Radial dose distributions and anisotropy characteristics were analysed …


Flagellar Coordination In A Swimming Multicellular Bacterium, Erandi Sachinthanie Imiya Mudiyanselage, Melina Mati, Alexander P. Petroff 2026 Clark University

Flagellar Coordination In A Swimming Multicellular Bacterium, Erandi Sachinthanie Imiya Mudiyanselage, Melina Mati, Alexander P. Petroff

Physics

Microbial locomotion is well understood when cells use either a small number of flagella or a high density of cilia. However many microbes live in an intermediate regime where coordination strategies such as flagellar bundles and metachronal waves are not possible. The mechanisms by which such organisms coordinate the motion of their swimming appendages are not well understood. Here, we study the only known obligatory multicellular bacterium, which are of the genus Magnetoglobus. Cells of this genus live exclusively in spherical communities called consortia, which are composed of a monolayer of tens of cells. Approximately a thousand of flagella project …


Computational Insights Into Nucleosome Dynamics In Epigenetics Using Molecular Dynamics Simulations, Rutika Patel 2026 The Graduate Center, City University of New York

Computational Insights Into Nucleosome Dynamics In Epigenetics Using Molecular Dynamics Simulations, Rutika Patel

Dissertations, Theses, and Capstone Projects

Nucleosome core particles (NCP) are the building blocks that form a highly organized and compact chromatin structure. Nucleosomes package DNA in the nucleus of eukaryotic cells. The NCP consists of about 147 base pairs of DNA wrapped around the histone octamer, with 1.65 superhelical turns in a left-handed manner. The histone octamer is composed of two copies of H3, H4, H2A, and H2B. Together with histone H1 and linker DNA, they further assemble into a higher-order chromatin structure. The nucleosome complex is stabilized by electrostatic interactions between positively charged histone residues and the negatively charged DNA backbone. To effectively access …


Developing A High-Resolution Off-Axis Common-Mode Digital Holographic Microscope, Lucy Cook 2026 Portland State University

Developing A High-Resolution Off-Axis Common-Mode Digital Holographic Microscope, Lucy Cook

University Honors Theses

Off-axis digital holographic microscopy (DHM) is a powerful tool for 3D, non-invasive live-cell tracking without moving parts. However, traditional setups face an inherent dilemma: split-path interferometers offer high spatial resolution but poor temporal stability, while more stable common-mode configurations are historically limited to lower numerical aperture (NA) regimes. This thesis bridges that gap by scaling a common-mode DHM architecture into a high-resolution benchtop instrument featuring NA = 0.65 objectives, paired with a high-power 520 nm laser source to combat transmission losses and sustain imaging frame rates across an expanded optical footprint. We map the multi-variable design space required to satisfy …


Computational-Experimental Synergy As A Predictive And Interpretive Tool Through Metal-Organic Framework Investigations, Cristian Sayers 2026 Lewis University

Computational-Experimental Synergy As A Predictive And Interpretive Tool Through Metal-Organic Framework Investigations, Cristian Sayers

Graduate Student Theses and Dissertations

In the search for tunable materials platforms capable of addressing both clean energy conversion and viable post-combustion carbon capture, metal-organic frameworks (MOFs) have emerged as a uniquely versatile class of porous solids offering high specific surface area, structural tunability, and chemically addressable metal nodes and organic linkers. Realizing their potential requires understanding behavior that spans atomic-scale electronic structure and bulk-scale property response, a regime in which neither computation nor experiment alone is sufficient. This work attempts to develop a tighter integration between density functional theory (DFT) and laboratory investigation, treating the two modalities as mutually informing probes of the same …


Taking A Deeper Look: Attributing Tonal Values Of Photolumens To Their Emulsions Using Scanning Electron Microscopy, Anna M. Moore 2026 Clemson University

Taking A Deeper Look: Attributing Tonal Values Of Photolumens To Their Emulsions Using Scanning Electron Microscopy, Anna M. Moore

All Theses

This thesis examines whether tonal variation in photolumens made with historic silver gelatin photographic papers can be linked to differences in elemental composition. Photolumens are cameraless photographic images created by placing objects directly on light-sensitive paper and exposing them to ultraviolet light. Because expired and historic darkroom papers often produce unpredictable colors and tones, this study asks whether visually defined tonal groups also show measurable chemical differences.

Twenty historic paper samples were exposed, documented, and sorted into five tonal groups based on visible image characteristics. Each sample was then analyzed using scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS) …


Membrane Organization Of Rheb And Rhoa: Roles In Function And Allosteric Druggability, Chase M. Hutchins 2026 University of Texas Health Science Center at Houston

Membrane Organization Of Rheb And Rhoa: Roles In Function And Allosteric Druggability, Chase M. Hutchins

Dissertations and Theses (Open Access)

Small GTPases of the Ras superfamily are membrane-bound molecular switches that regulate nearly all major cellular processes, and their dysregulation drives cancers, neurological disorders, and metabolic diseases. While anchored to cellular membranes, the catalytic domains of small GTPases undergo orientation dynamics, adopting distinct configurations that can occlude or expose effector-binding surfaces and modulate signaling output. These dynamics have been characterized in the Ras oncoproteins, but whether they extend across the superfamily and influence allosteric druggability has remained unknown.

In this dissertation, I address these questions through Rheb and RhoA, two small GTPases with complementary differences in subfamily lineage, membrane localization, …


Investigation Of Molecular Footprints In Ultra-High Diluted Homoeopathic Solutions Of Arnica Montana And Rhus Toxicodendron Through Combined Infrared And Impedance Spectroscopy, Sharbadeb Kundu, Usha Rani Dash, Chirasree RoyChaudhuri, Aindrila Roy, Sanatan Chattopadhyay, Rathin Chakravarty, Debadatta Nayak, Subhash Kaushik, Amit Roy Chowdhury, Ananya Barui, Subhadip Chakraborty 2026 Dr Bholanath Chakraborty Memorial Fundamental Research Laboratory of Homoeopathy (under CCRH, Ministry of AYUSH, Govt. of India), West Bengal, India; Centre for Healthcare Science and Technology, Indian Institute of Engineering Science and Technology, Shibpur, West Bengal, India AND Central Council for Research in Homoeopathy-Dr Anjali Chatterji Regional Research Institute for Homoeopathy, Kolkata, West Bengal, India

Investigation Of Molecular Footprints In Ultra-High Diluted Homoeopathic Solutions Of Arnica Montana And Rhus Toxicodendron Through Combined Infrared And Impedance Spectroscopy, Sharbadeb Kundu, Usha Rani Dash, Chirasree Roychaudhuri, Aindrila Roy, Sanatan Chattopadhyay, Rathin Chakravarty, Debadatta Nayak, Subhash Kaushik, Amit Roy Chowdhury, Ananya Barui, Subhadip Chakraborty

Indian Journal of Research in Homoeopathy

Background: The study of ultra-high diluted (UHD) solutions is a compelling and controversial domain in modern science. Despite numerous investigations and hypotheses, there is a lack of rigorous, reproducible empirical evidence supporting the existence of molecular footprints beyond the Avogadro's limit. Objective: This study conducted a detailed investigation of the molecular and electrical properties, focusing on hydrogen bonding and impedance to understand the fundamental nature of UHD solutions. Materials and methods: Combined impedance and infrared spectroscopic investigations were performed to probe the structural behaviour of relevant water networks at the molecular level of UHD alcoholic extract of Arnica montana (AM) …


Health Effects Of Cadmium And Manganese Exposure On Luteinizing Hormone Levels: A Pilot Study Of Female Infertility, Shatha F. Alhous, Anees A. Al-Hamzawi, Murtadha Sh. Aswood 2026 Department of Physics, College of Education, University of Al-Qadisiyah, Al-Diwaniyah, Ira

Health Effects Of Cadmium And Manganese Exposure On Luteinizing Hormone Levels: A Pilot Study Of Female Infertility, Shatha F. Alhous, Anees A. Al-Hamzawi, Murtadha Sh. Aswood

Al-Bahir

Female infertility occurs for many reasons, some unknown. Exposure to heavy metals is a risk factor that negatively impacts on female reproductive system. Therefore, this study aimed to evaluate the effect of cadmium Cd and manganese Mn on luteinizing hormone LH levels for females’ infertility. This study included a healthy group (n = 20), primary infertile females (n = 40), and secondary infertile females (n = 20) collected from Al-Zahraa hospital in Najaf center, Iraq. The Atomic Absorption Spectroscopy (AAS) was used to measure the cadmium and manganese concentrations and LH levels were measured by a Maglumi 800 from Snibe …


Sensing Negative-Cone Rotational Diffusion Of Dipole-Like Emitters, Yuanxin Qiu, Kaizhi A. Nie, Matthew D. Lew 2026 Washington University in St. Louis

Sensing Negative-Cone Rotational Diffusion Of Dipole-Like Emitters, Yuanxin Qiu, Kaizhi A. Nie, Matthew D. Lew

Electrical & Systems Engineering Publications and Presentations

Fluorescence anisotropy and single-molecule orientation-localization microscopy (SMOLM) are powerful techniques that quantify the rotational diffusion of dipole-like emitters, which is important for sensing molecular interactions and chemical environments at the nanoscale. Numerous theoretical and experimental studies have thoroughly characterized single-molecule rotations even when those rotations are much faster than the detector integration time. Here, we extend the theory of measuring rotational diffusion to situations where a single dipole rotates uniformly everywhere outside of an isotropic cone of a certain size, termed a negative cone. This scenario corresponds to negative fluorescence anisotropy 𝑟 and has been observed in emitters exhibiting strong …


Absolute Quantification And Identification Of Rna From Rna-Lipid Nanoparticles Using High Resolution Mass Spectrometry, Jason C. Funderburk, Yasir A. Alshehry, Matthew S. Halquist PhD, Sandro R.P. da Rocha PhD 2026 Virginia Commonwealth University

Absolute Quantification And Identification Of Rna From Rna-Lipid Nanoparticles Using High Resolution Mass Spectrometry, Jason C. Funderburk, Yasir A. Alshehry, Matthew S. Halquist Phd, Sandro R.P. Da Rocha Phd

Graduate Research Posters

Background

RNA therapeutics are a rising drug category with potential use for a range of conditions encompassing infectious diseases to therapies for cancer, diseases, and genetic disorders. RNA-lipid nanoparticles (RNA-LNPs) are the prominent delivery method for these therapeutics approved products include mRNA vaccines and polyneuropathy treatments. The emergency use authorizations and orphan drug status of current RNA-LNP drugs has allowed approval without finalization of the regulatory analytical procedures for quality monitoring. The objective of the study was to develop an LC-MS assay to simultaneously measure identity and concentration of two therapeutically relevant intact RNA constructs extracted from RNA-LNPs to enhance …


Absolute Quantification And Identification Of Rna From Rna-Lipid Nanoparticles Using High Resolution Mass Spectrometry, Jason C. Funderburk 2026 Virginia Commonwealth University

Absolute Quantification And Identification Of Rna From Rna-Lipid Nanoparticles Using High Resolution Mass Spectrometry, Jason C. Funderburk

Theses and Dissertations

RNA therapeutics are a rising drug category with potential use for a range of conditions encompassing infectious diseases to therapies for cancer, diseases, and genetic disorders. RNA-lipid nanoparticles (RNA-LNPs) are the prominent delivery method for these therapeutics approved products include mRNA vaccines and polyneuropathy treatments. The emergency use authorizations and orphan drug status of current RNA-LNP drugs has allowed approval without finalization of the regulatory analytical procedures for quality monitoring. The objective of the study was to develop an LC-MS assay to simultaneously measure identity and concentration of two therapeutically relevant intact RNA constructs extracted from RNA-LNPs to enhance quality …


Intersecting Physics And Medicine Through Computed Tomography, Christopher Wengert, Madouna Barsoum, Dominick Dingus 2025 Lipscomb University

Intersecting Physics And Medicine Through Computed Tomography, Christopher Wengert, Madouna Barsoum, Dominick Dingus

Student Scholar Symposium

Computed Tomography (CT) imaging is a cornerstone of modern medicine. Enabling detailed internal imaging for diagnostic and therapeutic applications. This project explores the physics underlying CT imaging, highlighting how fundamental principles of physics integrate seamlessly with medical advancements. We will examine X-Ray generation, attenuation, and image reconstruction, demonstrating how varying tissue densities influence scan results. The role of mathematical algorithms, such as filtered back protection and iterative reconstruction, will be discussed in relation to image clarity and radiation does optimization.

Additionally, we will address the balance between image resolution and patient safety, emphasizing the importance of minimizing radiation exposure while …


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