Modulation Of Mechanical Stress Mitigates Anti-Dsg3 Antibody-Induced Dissociation Of Cell–Cell Adhesion,
2021
University of Nebraska-Lincoln
Modulation Of Mechanical Stress Mitigates Anti-Dsg3 Antibody-Induced Dissociation Of Cell–Cell Adhesion, Xiaowei Jin, Jordan Rosenbohm, Eunju Kim, Amir Monemian Monemianesfahani, Kristina Seiffert-Sinha, James K. Wahl Iii, Jung Yul Lim, Animesh A. Sinha, Ruiguo Yang
Department of Mechanical and Materials Engineering: Faculty Publications
It is becoming increasingly clear that mechanical stress in adhesive junctions plays a significant role in dictating the fate of cell–cell attachment under physiological conditions. Targeted disruption of cell–cell junctions leads to multiple pathological conditions, among them the life-threatening autoimmune blistering disease pemphigus vulgaris (PV). The dissociation of cell–cell junctions by autoantibodies is the hallmark of PV, however, the detailed mechanisms that result in tissue destruction remain unclear. Thus far, research and therapy in PV have focused primarily on immune mechanisms upstream of autoantibody binding, while the biophysical aspects of the cell– cell dissociation process leading to acantholysis are less …
Modulation Of Mechanical Stress Mitigates Anti-Dsg3 Antibody-Induced Dissociation Of Cell–Cell Adhesion,
2021
University of Nebraska-Lincoln
Modulation Of Mechanical Stress Mitigates Anti-Dsg3 Antibody-Induced Dissociation Of Cell–Cell Adhesion, Xiaowei Jin, Jordan Rosenbohm, Eunju Kim, Amir Monemian Esfahani, Kristina Seiffert-Sinha, James K. Wahl Iii, Jung Yul Lim, Animesh A. Sinha, Ruiguo Yang
Department of Mechanical and Materials Engineering: Faculty Publications
It is becoming increasingly clear that mechanical stress in adhesive junctions plays a significant role in dictating the fate of cell–cell attachment under physiological conditions. Targeted disruption of cell–cell junctions leads to multiple pathological conditions, among them the life-threatening autoimmune blistering disease pemphigus vulgaris (PV). The dissociation of cell–cell junctions by autoantibodies is the hallmark of PV, however, the detailed mechanisms that result in tissue destruction remain unclear. Thus far, research and therapy in PV have focused primarily on immune mechanisms upstream of autoantibody binding, while the biophysical aspects of the cell– cell dissociation process leading to acantholysis are less …
Common Pool Resource Management: Assessing Water
Resources Planning For Hydrologically Connected Surface
And Groundwater Systems,
2021
University of Nebraska-Lincoln
Common Pool Resource Management: Assessing Water Resources Planning For Hydrologically Connected Surface And Groundwater Systems, Francisco Munoz-Arriola, Tarik Abdel-Monem, A. Amaranto
Department of Mechanical and Materials Engineering: Faculty Publications
Common pool resource (CPR) management has the potential to overcome the collective action dilemma, defined as the tendency for individual users to exploit natural resources and contribute to a tragedy of the commons. Design principles associated with effective CPR management help to ensure that arrangements work to the mutual benefit of water users. This study contributes to current research on CPR management by examining the process of implementing integrated management planning through the lens of CPR design principles. Integrated management plans facilitate the management of a complex common pool resource, ground and surface water resources having a hydrological connection. Water …
Part-Scale Thermal Simulation Of Laser Powder Bed Fusion Using Graph Theory: Effect Of Thermal History On Porosity, Microstructure Evolution, And Recoater Crash,
2021
University of Nebraska - Lincoln
Part-Scale Thermal Simulation Of Laser Powder Bed Fusion Using Graph Theory: Effect Of Thermal History On Porosity, Microstructure Evolution, And Recoater Crash, Reza Yavari, Ziyad Smoqi, Alex Riensche, Ben Bevans, Humaun Kobir, Heimdall Mendoza, Hyeyun Song, Kevin Cole, Prahalada Rao
Department of Mechanical and Materials Engineering: Faculty Publications
Flaw formation in laser powder bed fusion (LPBF) is influenced by the spatiotemporal temperature distribution – thermal history – of the part during the process. Therefore, to prevent flaw formation there is a need for fast and accurate models that can predict the thermal history as a function of the part shape and processing parameters. In previous work, a thermal modeling approach based on graph theory was used to predict the thermal history in LPBF parts in less-than 20% of the time required by finite element-based models with error within 10% of experimental measurements. The present work transitions toward the …
Shock Migration On An Oscillating Straked Delta Wing Using An Unsteady Euler Solver,
2021
Air Force Institute of Technology
Shock Migration On An Oscillating Straked Delta Wing Using An Unsteady Euler Solver, Alexander J. Brown
Theses and Dissertations
This research contributes to the understanding of Shock Induced Trailing Edge Separation (SITES) as a driver of Limit Cycle Oscillation (LCO) by performing a computational investigation of nonlinear aerodynamic phenomena on a straked delta wing in transonic flow, oscillating in pitch. ZEUS, an Euler-based aeroelastic solver with a boundary layer coupling scheme meant to capture viscous flow effects within the boundary layer, was used to analyze aerodynamic flow around the wing for various mean incidence angles, oscillation amplitudes, and Mach numbers within the transonic region. The dynamic characteristics of the airflow around the wing were investigated in order to characterize …
Chilling And Heat Accumulation Of Fruit And Nut Trees And
Flower Bud Vulnerability To Early Spring Low Temperatures In
New Mexico: Meteorological Approach,
2021
New Mexico State University
Chilling And Heat Accumulation Of Fruit And Nut Trees And Flower Bud Vulnerability To Early Spring Low Temperatures In New Mexico: Meteorological Approach, Koffi Djaman, Komlan Koudahe, Murali Darapuneni, Suat Irkmak
Department of Mechanical and Materials Engineering: Faculty Publications
Fruit and nut trees production is an important activity across the southwest United States and this production is greatly impacted by the local climate. Temperature is the main environmental factor influencing the growth and the productivity of the fruit and nut trees as it affects the trees’ physiology and the vulnerability of flower bud, flowers, and young fruit and nut to the low temperatures or spring frost. The objective of the present study is to estimate the chilling and heat accumulation of fruit and nut trees across New Mexico. Three study sites as Fabian Garcia, Los Lunas, and Farmington were …
Characterization Of The Strain-Rate–Dependent Mechanical Response Of Single Cell–Cell Junctions,
2021
University of Nebraska-Lincoln
Characterization Of The Strain-Rate–Dependent Mechanical Response Of Single Cell–Cell Junctions, Amir Monemian Esfahani, Jordan Rosenbohm, Bahareh Tajvidi Safa, Nickolay V. Lavrik, Grayson Minnick, Quan Zhou, Fang Kong, Xiaowei Jin, Eunju Kim, Ying Liu, Yongfeng Lu, Jung Yul Lim, James K. Wahl Iii, Ming Dao, Changjin Huang, Ruiguo Yang
Department of Mechanical and Materials Engineering: Faculty Publications
Cell–cell adhesions are often subjected to mechanical strains of different rates and magnitudes in normal tissue function. However, the rate-dependent mechanical behavior of individual cell– cell adhesions has not been fully characterized due to the lack of proper experimental techniques and therefore remains elusive. This is particularly true under large strain conditions, which may potentially lead to cell–cell adhesion dissociation and ultimately tissue fracture. In this study, we designed and fabricated a single-cell adhesion micro tensile tester (SCAμTT) using twophoton polymerization and performed displacement-controlled tensile tests of individual pairs of adherent epithelial cells with a mature cell–cell adhesion. Straining the …
Irrigation Management In Potato (Solanum Tuberosum L.)
Production: A Review,
2021
New Mexico State University
Irrigation Management In Potato (Solanum Tuberosum L.) Production: A Review, Koffi Djaman, Suat Irkmak, Komlan Koudahe, Samuel Allen
Department of Mechanical and Materials Engineering: Faculty Publications
Limited water resources coupled with the increase of the human population calls for more efficient use of water in irrigated agriculture. Potato (Solanum tuberosum L.) is one of the most widely grown crops worldwide and is very sensitive to water stress due to its shallow rooting system. With the dilemma of potato sensitivity to drought and limited available water resources restricting crop production, researchers and crop growers have been investigating different approaches for optimizing potato yield and improving crop water use efficiency under different irrigation methods. While potato response to water is affected by other management practices such as fertilizer …
Ultrasonic Mapping Of Hybrid Additively Manufactured 420 Stainless Steel,
2021
University of Nebraska-Lincoln
Ultrasonic Mapping Of Hybrid Additively Manufactured 420 Stainless Steel, Luz D. Sotelo, Haitham Hadidi, Cody S. Pratt, Michael P. Sealy, Joseph A. Turner
Department of Mechanical and Materials Engineering: Faculty Publications
Metal hybrid additive manufacturing (AM) processes are suitable to create complex structures that advance engineering performance. Hybrid AM can be used to create functionally graded materials for which the variation in microstructure and material properties across the domain is created through a synergized combination of fully coupled manufacturing processes and/or energy sources. This expansion in the engineering design and manufacturing spaces presents challenges for nondestructive evaluation, including the assessment of the sensitivity of nondestructive measurements to functional gradients. To address this problem, linear ultrasound measurements are used to interrogate 420 stainless steel coupons from three manufacturing methods: wrought, AM, and …
Unveiling Precipitation Behavior In Mg-Y Based Alloys,
2021
Shanghai Jiaotong University
Unveiling Precipitation Behavior In Mg-Y Based Alloys, Qingchun Zhu, Yangxin Li, Zhigang Ding, Jian Wang, Yuxuan Liu, Huan Zhang, Tian Xie, Mingxu Wang, Hong Zhu, Tao Ying, Wei Liu, Xiaoquin Zeng
Department of Mechanical and Materials Engineering: Faculty Publications
Mg-Y based alloys exhibit a promising combination of strength and deformability through tuning precipitation and solute strengthening mechanisms and tailoring the activity of non-basal dislocations. Understanding the precipitation sequence of Mg-Y based alloys and its dependence on Yttrium concentration in the matrix will provide a guideline for fine tuning structure, morphology and distribution of precipitates in Mg-Y based alloys. In this paper, we explore the precipitation behaviors of Mg-11Y (wt%) and Mg-11Y-1Al (wt%) alloys using aberration-corrected scanning transmission electron microscopy, and rationalize the experimental observations based on first-principles density functional theory calculations. The precipitation sequence during ageing at 225 °C …
A Single-Stage Passive Vibration Isolation System For Scanning Tunneling Microscopy,
2021
California Polytechnic State University, San Luis Obispo
A Single-Stage Passive Vibration Isolation System For Scanning Tunneling Microscopy, Toan T. Le
Master's Theses
Scanning Tunneling Microscopy (STM) uses quantum tunneling effect to study the surfaces of materials on an atomic scale. Since the probe of the microscope is on the order of nanometers away from the surface, the device is prone to noises due to vibrations from the surroundings. To minimize the random noises and floor vibrations, passive vibration isolation is a commonly used technique due to its low cost and simpler design compared to active vibration isolation, especially when the entire vibration isolation system (VIS) stays inside an Ultra High Vacuum (UHV) environment. This research aims to analyze and build a single-stage …
The Role Of Microenvironmental Cues And Mechanical Loading Milieus In Breast Cancer Cell Progression And Metastasis,
2021
University of Nebraska-Lincoln
The Role Of Microenvironmental Cues And Mechanical Loading Milieus In Breast Cancer Cell Progression And Metastasis, Brandon D. Riehl, Eunju Kim, Tasneem Bouzid, Jung Yul Lim
Department of Mechanical and Materials Engineering: Faculty Publications
Cancer can disrupt the microenvironments and mechanical homeostatic actions in multiple scales from large tissue modification to altered cellular signaling pathway in mechanotransduction. In this review, we highlight recent progresses in breast cancer cell mechanobiology focusing on cell-microenvironment interaction and mechanical loading regulation of cells. First, the effects of microenvironmental cues on breast cancer cell progression and metastasis will be reviewed with respect to substrate stiffness, chemical/topographic substrate patterning, and 2D vs. 3D cultures. Then, the role of mechanical loading situations such as tensile stretch, compression, and flow-induced shear will be discussed in relation to breast cancer cell mechanobiology and …
Quantification Of Nitric Oxide Concentration Using
Single-Walled Carbon Nanotube Sensors,
2021
University of Nebraska - Lincoln
Quantification Of Nitric Oxide Concentration Using Single-Walled Carbon Nanotube Sensors, Jakob Meier, Joseph Stapleton, Eric M. Hofferber, Abigail Haworth, Stephen D. Kachman, Nicole M. Iverson
Department of Mechanical and Materials Engineering: Faculty Publications
Nitric oxide (NO), a free radical present in biological systems, can have many detrimental effects on the body, from inflammation to cancer. Due to NO’s short half-life, detection and quantification is difficult. The inability to quantify NO has hindered researchers’ understanding of its impact in healthy and diseased conditions. Single-walled carbon nanotubes (SWNTs), when wrapped in a specific single-stranded DNA chain, becomes selective to NO, creating a fluorescence sensor. Unfortunately, the correlation between NO concentration and the SWNT’s fluorescence intensity has been difficult to determine due to an inability to immobilize the sensor without altering its properties. Through the use …
Mechanical Behavior Of Al–Al2cu–Si And Al–Al2cu Eutectic Alloys,
2021
University of Michigan-Ann Arbor
Mechanical Behavior Of Al–Al2cu–Si And Al–Al2cu Eutectic Alloys, Qian Lei, Jian Wang, Amitava Mitra
Department of Mechanical and Materials Engineering: Faculty Publications
In this study, laser rapid solidification technique was used to refine the microstructure of ternary Al–Cu–Si and binary Al–Cu eutectic alloys to nanoscales. Micropillar compression testing was performed to measure the stress–strain response of the samples with characteristic microstructure in the melt pool regions. The laser-remelted Al–Al2Cu–Si ternary alloy was observed to reach the compressive strength of 1.59 GPa before failure at a strain of 28.5%, which is significantly better than the as-cast alloy with a maximum strength of 0.48 GPa at a failure strain of 4.8%. The laser-remelted Al–Cu binary alloy was observed to reach the compressive …
Multifunctional Polydopamine Nanomaterials For Biomedical And Environmental Applications,
2021
Washington University in St. Louis
Multifunctional Polydopamine Nanomaterials For Biomedical And Environmental Applications, Hamed Gholami Derami
McKelvey School of Engineering Graduate Student Theses & Dissertations
Polydopamine (PDA), a synthetic and organic material, has emerged as a promising materialplatform for various applications in energy, environmental, and biomedical fields. PDA, formed by self-polymerization of dopamine, is rich in catechol and amine groups, which facilitate covalent conjugation and/or other non-covalent interactions with organic and inorganic materials. It is highly biocompatible, biodegradable, has broadband light absorption spectrum and excellent light-to-heat conversion efficiency. Also, it is easy to synthesize and functionalize. The combination of excellent characteristics of polydopamine-based nanomaterials, make them a promising adsorbent agent for environmental wastewater treatment and photothermal agent for biomedical applications. In the first half of …
Mechanical Strength Of Germanium Doped Low Oxygen Concentration Czochralski Silicon And The Effect Of Oxygen On Nitrogen Dissociation In Silicon,
2021
Washington University in St. Louis
Mechanical Strength Of Germanium Doped Low Oxygen Concentration Czochralski Silicon And The Effect Of Oxygen On Nitrogen Dissociation In Silicon, Junnan Wu
McKelvey School of Engineering Graduate Student Theses & Dissertations
During the Czochralski growth of silicon, it is inevitable for oxygen to be incorporated into the silicon crystal from the quartz crucible. Interstitial oxygen improves the mechanical strength of silicon by pinning and locking dislocations, but also generates thermal donors during device processes, shifting the electrical resistivity. For silicon wafers used in radio frequency (RF) applications, it is important to ensure the high resistivity of the substrates for good RF characteristics. Therefore, the oxygen level in these high resistivity silicon wafers is kept very low (< 2.5 × 1017 atoms/cm3) by carefully controlling the Czochralski growth conditions, in order to reduce the thermal donor concentration to an acceptable level. Silicon on insulator (SOI) substrates made from high resistivity wafers have been widely used for RF applications. SOI manufacturing includes multiple high temperature thermal cycles (1000 – 1100 °C), during which the high resistivity wafers are prone to slip and warpage. Therefore, it is technologically important to recover some of the lost mechanical strength due to the lack of oxygen by introducing electrically inactive impurities to suppress the dislocation generation and mobility in silicon. Germanium (Ge) as an isovalent impurity is 4% larger in size and forms a solid solution with silicon in the entire concentration range. Previous works have shown Ge doping at high concentrations above 6 × 1019 atoms/cm3 increased mechanical strength of silicon with high oxygen concentration (~ 1 × 1018 atoms/cm3). In this work, we explore the effect of Ge doping (7 - 9 × 1019 atoms/cm3) on the mechanical strength of low oxygen concentration (< 2 × 1017 atoms/cm3) silicon, where the oxygen associated dislocation locking and pinning are very low. A mechanical bending test was used to study the average dislocation migration velocity and the critical shear stress of dislocations motion at 600 – 750 °C for Ge doped, nitrogen doped, and undoped low oxygen samples, as well as nitrogen doped float-zone and un-doped high oxygen concentration samples. Next, we fabricated SOI substrates using these high resistivity wafers and compared their slip generation rates and the slip-free epitaxial grow temperature windows after the high temperature thermal cycles (> 1000 °C). Our results indicate at lower temperature Ge doesn’t affect the dislocation mobility …
Nanoscale Enhancement Of Photosensitized Radionuclide Stimulated Therapy,
2021
Washington University in St. Louis
Nanoscale Enhancement Of Photosensitized Radionuclide Stimulated Therapy, Daniel Douglas Lane
McKelvey School of Engineering Graduate Student Theses & Dissertations
Photodynamic therapy (PDT) provides efficient tumor killing through the generation of reactive oxygen species (ROS) from the optical excitation of a photosensitizer (PS). Furthermore, this mechanism is highly immune stimulating, providing systemic tumor immunity with a reduction in metastasis. However, these materials had previously been limited by their dependence upon external light sources, allowing treatment of only laser-accessible malignancy. With the recent development of photosensitized radiation stimulated therapy (PRaST) this depth dependence is broken through co-localization of radionuclides and semiconducting photosensitizers. This dissertation focuses on the enhancement of titanium dioxide (TiO2) based PRaST agents through understanding of TiO2 material parameters …
Sensitive X-Ray And Gamma-Ray Detectors Including Perovskite Single Crystals,
2021
University of Nebraska - Lincoln
Sensitive X-Ray And Gamma-Ray Detectors Including Perovskite Single Crystals, Jinsong Huang, Haotong Wei
Department of Mechanical and Materials Engineering: Faculty Publications
Perovskite single crystal X-ray and gamma-ray radiation detector devices include an X-ray and gamma-ray wavelength responsive active layer including a perovskite single crystal. The perovskite single crystal is a perovskite single crystal having a structure of ABX3 , wherein A is methyl ammonium ( CH2NH2+), CS+, formamidinum ( H2NCHNH2+) , or Rb+ or a mixture thereof, B is Pb2+ which can be partially or completely replaced by other ions including Bi3+, Sb3+, Sn2+ or a mixture thereof, and X is a halide …
Mini Rc Baja Car,
2021
Central Washington University
Mini Rc Baja Car, Jason Schindler
All Undergraduate Projects
Incorporating each aspect of engineering incorporated into a senior project is difficult. That is why an RC Baja car is a great senior project for Mechanical Engineering students. The approach that students must take to design, construct, and test the car is to set parameters, and to make overall goals that can be easily measured. These goals include, but not limited to things like a $700 budget and the ability to withstand a 1-foot drop to a flat surface on all four wheels simultaneously. First, the design must meet the specifications and rules that are set previously. This ensures that …
Use Of Energy Consumption During Milling To Fill A Measurement Gap In Hybrid Additive Manufacturing,
2021
University of Nebraska-Lincoln
Use Of Energy Consumption During Milling To Fill A Measurement Gap In Hybrid Additive Manufacturing, K. L. M. Avegnon, P. Noll, M. R. Uddin, G. Madireddy, R. Williams, A. Achuthan, M. P. Sealy
Department of Mechanical and Materials Engineering: Faculty Publications
Coupling additive manufacturing (AM) with interlayer peening introduces bulk anisotropic properties within a build across several centimeters. Current methods to map high resolution anisotropy and heterogeneity are either destructive or have a limited penetration depth using a nondestructive method. An alternative pseudo-nondestructive method to map high-resolution anisotropy and heterogeneity is through energy consumption during milling. Previous research has shown energy consumption during milling correlates with surface integrity. Since surface milling of additively manufactured parts is often required for post-processing to improve dimensional accuracy, an opportunity is available to use surface milling as an alternative method to measure mechanical properties and …
