bluuebunny/crossref_metadata_2025_split huggingface dataset:
Adipose Tissue-Derived Stromal Cells Grown in Three-Dimensional Aliginate Constructs Display a Chondrogenic Phenotype
Authors: Erickson Geoffrey R. , Gimble Jeffrey M. , Franklin Dawn , Guilak Farshid 
Published: November 2021

Abstract
Articular cartilage is the connective tissue that lines the surfaces of diarthrodial joints in the human body. Because cartilage is avascular, aneural, and alymphatic, it has a limited capacity for repair. Techniques such as microfracture, transplantation of autologous cartilage, and allograft or xenograft transplantations have not proven fully effective in treating cartilage damage. Current therapy is focusing on cell-based treatments such as autologous chondrocyte transplantation [1,2]. However, this method faces several limitations, as the donor site can provide a limited number of cells and the harvesting procedure itself may cause significant local morbidity. The goal of this study was to examine the chondrogenic potential of an autologous source of undifferentiated stromal cells derived from subcutaneous fat. It has been shown that chondrocytes embedded in a three-dimensional matrix retain a differentiated phenotype and produce cartilage-associated proteins [3]. In addition, it has been shown that alginate or agarose can support the formation of an extracellular matrix over time [4,5]. The goal of this study was to examine the chondrogenic potential of adipose-derived stromal cells with the ultimate goal of developing a “tissue engineering” method to regenerate articular cartilage.
Development of Tissue-Engineered Human Articular Cartilage
Authors: Applegate Mark A. 
Published: November 2021

Abstract
Disability due to joint pain is increasing as our society ages. This pain often results from cartilage degeneration in joints due to osteoarthritis or trauma. Cartilage damage from sports injuries is common and the normal repair response results in the formation of fibrous tissue that is inferior to normal cartilage in structure and function and eventually degenerates with time. As a result, tens of thousands of total knee replacements and other surgical procedures are performed each year to repair cartilage defects in the knee. A common clinical treatment for cartilage lesions is debridement of the damaged tissue followed by drilling into the subchondral bone to stimulate tissue regeneration. Although this procedure often provides pain relief, it does not restore long-term function and frequently hastens additional degeneration of the injured site. Alternative procedures for repair or regeneration of human articular cartilage are needed.
Measuring Cellular Forces Using BioMEMS
Authors: LeDuc Philip , LaVan David , Bao Gang 
Published: November 2021

Abstract
In recent years cellular biomechanics has attracted much attention in various fields including biology, medicine, and engineering. Although the ability of a cell to sense and respond to mechanical forces is a focus of many investigations, determining the specifics of how a mechanical stimulus directly affects the behavior and function of a living cell remains a daunting task. Here, by combining the chip technology that is able to create structures on the same size scale as cells, a biological microelectromechanical systems (BioMEMS) device is developed and utilized to study the force generation, local perturbation and deformation of a single cell.
Moment Arm Calculations From In-Vivo Kinematic Data: Applications to the Trapezius Muscle
Authors: Karduna Andrew R. , McClure Phil W. 
Published: November 2021

Abstract
Alterations in scapular movement patterns are believed to be associated with muscle weakness, fatigue, and paralysis. Due to the control that muscles exert on scapular position, it is important to understand their mechanical efficiency. Previous researchers have used the principle of virtual work to assess shoulder muscle moment arms, but these studies have focused on the glenohumeral joint [1,2]. The purpose of this investigation was to develop an approach for studying scapular muscle moment arms - specifically focusing on the middle and upper trapezius.
Loading Evaluation of Knee Joint During Walking Using the Next Generation Knee Simulator
Authors: Maletsky Lorin P. , Hillberry Ben M. 
Published: November 2021

Abstract
Even with the advances in material selection, processing, and articular geometry for knee prostheses, there is still a need for in vitro evaluation of these components. The high occurrence of revision surgeries for failed prosthetics suggests that the component designs can still be improved. While historically the typical total knee recipient was an elderly woman, components are being implanted in younger patients who wish to lead more active lives with their new artificial knees. Therefore, the testing of new prostheses must be more rigorous and demanding than done previously. For these reasons a new five-axis electro-hydraulic knee simulator was constructed.
Biomechanical Analysis of Coronary Arteries Using Designed Experiments and a Complementary Energy Model
Authors: Dixon Stacey A. , Vito Raymond P. , Heikes Russell G. 
Published: November 2021

Abstract
To assist in the design of a compliant coronary vascular graft, a constitutive equation predicting the biomechanical properties of healthy coronary arteries was determined. An experimental design in the physiological range of force and pressure was used to improve data collection. Using a logarithmic complementary energy formulation of the constitutive equation resulted in an exceptional fit to the data. Comparisons showed statistically significant differences between the porcine left anterior descending [LAD] and right coronary artery [RCA] (p&lt;0.02) but no differences between the left circumflex [LCX] and LAD or LCX and RCA (p&gt;0.05).
Preliminary Design Considerations and Feasibility of a Biomimicking Tissue-Engineered Vascular Graft
Authors: Stitzel Joel D. , Bowlin Gary L. 
Published: November 2021

Abstract
Development of an ideal vascular replacement has been addressed with increasing urgency in recent years. To date, appropriate replacements for only large diameter bypass grafts have been realized, employing the use of Dacron and expanded polytetrafluoroethylene. A solution for small diameter (&lt;6 mm I.D.) vessel bypass, however, has not yet been found. This is due mainly to acute thrombotic occlusion and chronic anastomotic hyperplasia that is introduced into these grafts due to the low blood flow velocities experienced by smaller caliber vessels and compliance mismatch between prosthetic and native vessel, respectively [1].
Material Properties of Abdominal Aortic Aneurysm Wall From Uniaxial Tests
Authors: Thubrikar Mano J. , Labrosse Michel , Al-Soudi Jihad , Fowler Brett , Robicsek Francis 
Published: November 2021

Abstract
Abdominal aortic aneurysms (AAA) rupture when the aortic wall cannot withstand the stresses and strains induced by the pulsatile blood pressure. In recent years, different mechanical models of aneurysms have been presented (Vorp et al., 1998, Di Martino et al., 1998, Thubrikar et al., 1999). Although powerful modeling tools such as finite elements are available, there is still a need for experimental data concerning the mechanical properties of the aneurysm wall.
Effect of Initial Tube Strain on Self-Excited Oscillation of Collapsible Tube Flow
Authors: Xia Yupeng , Hayase Toshiyuki , Hayashi Satoru , Hamaya Tsuyoshi 
Published: November 2021

Abstract
Since human organs, such as blood vessels, tracheas and urethras, have similar characteristics to collapsible tubes, a lot of studies on both steady and unsteady flow through the collapsible tubes have been done in biological and physiological fields [1, 2]. Recently, Sakurai et al carried out an experimental analysis concerning the effect of longitudinal tension on collapsible tube flow [3]. However, the real figure of this complex system, including the influence of the tube parameters on self-excited oscillation is still not sufficiently understood. In present report an experiment was performed to investigate the dynamic characteristics of a collapsible tube flow. The effect of initial axial strain of the tube on the self-excited oscillation was studied by changing the initial stretch of a thin-walled silicone rubber tube for various values of supply flow rate.
Development of a Tibial Slider to Evaluate and Validate a Finite Element Model for Friction in Total Knee Implants
Authors: Nowak Michael D. , Shaw Kenneth , Lewis Courtland 
Published: November 2021

Abstract
More than 200,000 people in the United States annually undergo knee replacement as a means of diminishing pain and stiffness and restoring mobility, and the number is expected to increase with further advancements in joint replacement procedures [Duke, 1999]. Total knee replacement is performed on people with severe degenerative joint disorder such as osteoarthritis in which the articular surfaces of the knee deteriorate, leading to severe pain, limitation or loss of function and/or deformity of the joint.
Finite Element Simulation of Cartilage Mechanics During Diarthrodial Joint Motion Using Physiological Data
Authors: Ün Kerem , Donzelli Peter S. , Spilker Robert L. 
Published: November 2021

Abstract
Moving contact is fundamental to understanding the mechanical environment of articular cartilage in diarthrodial joints. This study presents a method for approximating three-dimensional (3D) moving contact of biphasic tissue layers using a time-dependent penetration method. This technique has been implemented in a custom finite element solution framework for large-scale simulation that includes a graphical user interface, automatic meshing, and visualization tools. Thus, physiological geometry and load levels can be simulated by this approximate technique. The method is illustrated for canonical and physiological problems representing the glenohumeral joint (GHJ) of the shoulder.
A Method to Calculate Volumetric Integral Averages From a Finite Element Solution
Authors: Miller Echo M. , Donzelli Peter S. , Spilker Robert L. 
Published: November 2021

Abstract
The inhomogeneity and anisotropy of articular cartilage has been experimentally verified, but little has been done to quantify the effects of such material variation on mechanical behavior. We present a method to calculate volume-averaged quantities over tissue regions, used in conjunction with a 3D biphasic finite element analysis. Such average quantities can be used in parametric studies of different material property models, readily permitting statistical comparisons that are difficult with point-wise quantities.
Study of Ho:YAG Laser Generated Underwater Shock Waves and Cavity Bubble for Revascularization Therapy
Authors: Hosseini S. H. R. , Hirano T. , Onodera O. , Takayama K. 
Published: November 2021

Abstract
For applying shock waves to precise medical procedures like neurosurgery, a reliable generation of micro shock waves is required. Such sensitive applications make limits on usage of conventional underwater shock wave sources like Extracoporeal Shock Waves ESW [1] or micro explosives [2]. In the present study a Q-switched Ho:YAG laser and an optical fiber are used. Advantages of this method over previous shock wave sources are two order of magnitude reduction in focusing area if compared with ESW and elimination of product gases of micro explosives. Nakahara and Nagayama [3] studied underwater shock waves emanated from surface of an optical fiber by pulse Nd:YAG laser input using shadowgraph technique. Their qualitative study limited to visualization of shock waves at its early stage. The present research aims to clarify quantitatively process of the shock wave generation by direct laser beam irradiation through optical fibers, growth and behavior of generated cavities, and structure of heat induced flow in front of the optical fiber.
In Vitro Stain Transport in Canaliculi of Rat Femora Under Cyclic Loading
Authors: Li Bixia , Norman Timothy L. 
Published: November 2021

Abstract
In this study, rat femurs were used to test the diffusion and mechanical transport properties of a fluroscein stain tracer in microvessels of bone. Fluroscein was used as a tracer to visualize the fluid flow behavior using confocal microscopy. It was found that stain transport occurs due to diffusion under static conditions and due to mechanical loading. The transport increased with cyclic load level and frequency. Our results also show that stain transport at the canaliculi level occurs rapidly in rat bone.
Vehicle Crashworthiness in Vertical Drop Tests
Authors: Herbst Brian , Forrest Steven , Meyer Steven E. , Chng David , Davis Mark , Sances Anthony 
Published: November 2021

Abstract
Inverted drop testing of vehicles is a methodology that has long been used by the automotive industry and by researchers to test roof integrity. In our laboratory, the inverted drop test methodology was employed on a late model production sport utility vehicle (SUV) in order to simulate the damage incurred by a real world rollover accident. The extent and shape of residual damage matched well with the accident damage. A second vehicle was reinforced based upon techniques and methods published by Herbst et al1, which reduced the crush from 11″ to 2.75″. Incorporation of these techniques demonstrated an increase in roof strength of approximately four-fold with a minor weight addition. The modified vehicle was dropped a second time for a cumulative drop height of 3 feet. The modified vehicle after the second test crushed approximately 3–4″ over the driver seating location and 7″ at the top of the driver’s A-pillar.
The Effect of Vertical Acceleration on Emergency Locking Seatbelt Retractors
Authors: Meyer Steven E. , Forrest Stephen , Hayden Joshua , Herbst Brian , Sances Anthony 
Published: November 2021

Abstract
Contemporary production seatbelt retractors have been proven very effective in the crash environment for which they have been primarily designed and most adequately tested, that is, in the full frontal crash mode. The National Traffic and Motor Vehicle Safety Act of 1966 outlines specific crash test and occupant injury measure requirements for testing and evaluation of seatbelt systems in production vehicles. Automobile manufacturers routinely test exhaustively in compliance of these requirements with respect to full frontal barrier crashes. However, government requirements are not nearly as complete for alternative accident modes often seen in the real world. Offset, angled, override, underride, and rollover crashes will often require seatbelt retractors to manage acceleration pulses in varying directions, including the vertical plane. Occupant motions during these real world accident modes may also impart loads into the belts and belt hardware (webbing and buckle assemblies) that also may not be immediately apparent in the frontal barrier test mode.
Influence of Graft/Host Diameter Ratio on the Hemodynamics in Sequential ITA Anastomoses
Authors: Bonert Michael , Myers Jerry G. , Fremes Stephen E. , Ethier C. Ross 
Published: November 2021

Abstract
Multivessel grafting with internal thoracic artery (ITA) conduits may improve the long-term results of coronary surgery for patients with multivessel coronary disease. Sequential ITA grafting has been increasingly used as a means of allowing a single ITA to revascularize a greater amount of the myocardium (Izzat et al, 1994). In this procedure, the graft first supplies blood to a coronary artery via a side-to-side anastomoses and then delivers blood to a second site in the coronary vasculature through an end-to-side anastomosis. However, it is unclear if the complex geometry and hemodynamic patterns in the side-to-side anastomosis contribute to the development of intimal hyperplasia, as reported for end-to-side anastomoses (Bassiouny et al. 1992). In a previous study we studied the hemodynamics of side-to-side anastomosis when graft and host diameters are equal (Bonert et al., 1999). In this study, we examined the wall shear stress (WSS) characteristics in idealized models of a “parallel” and a “diamond” side-to-side anastomoses for the case in which the graft diameter is substantially larger than the host diameter (Lei et al., 1996). Regions of specific interest were those exhibiting low WSS and rapidly changing WSS (high spatial WSS gradient) both of which have been suggested to promote intimal hyperplasia.
Hydrodynamic Modeling of Cerebrospinal Fluid Motion Within the Spinal Cavity
Authors: Yardimci M. Atif , Loth Francis , Alperin Noam 
Published: November 2021

Abstract
In the present work, a geometric and hydrodynamic characterization of an anatomically relevant spinal canal model is presented. A numerical model was employed to investigate effects of cross-sectional geometry and spinal cord motion on unsteady velocity, shear stress, and pressure gradient fields. The velocity field was shown to be blunt, due to the inertial character of the flow, with velocity peaks located near the boundaries of the spinal canal rather than at the midpoint between boundaries. The pressure gradient waveform was found to be almost exclusively dependent on the flow waveform and cross-sectional area.
Influence of Zeta Potential on the Lubrication Between Ultra-High Molecular Weight Polyethylene and CoCrMo Alloy
Authors: Kitano Toshio 
Published: November 2021

Abstract
Zeta potential is the potential that is related to the electric charge of the surface. Zeta potential influences tribological surface phenomenons. In the field of Orthopaedic surgery, osteolysis due to wear debris is one of the most difficult complications following total joint arthroplasty. Improvement of long term results and decrease of the revision rate demand that the lubrication mechanism of total replacement joint be revealed and friction and wear of surface be reduced. The purpose of this study is to clarify the correlation between zeta potential of ultra-high molecular weight polyethylene (UHMWPE) and friction in total replacement joint under boundary lubrication condition and to answer the effect of glycoprotein on total replacement joint.
A Study of Hydroforming for Processing Composites
Authors: Zampaloni Michael A. , Pourboghrat Farhang , Benard Andre 
Published: November 2021

Abstract
The use of hydroforming to shape complex composite parts is proposed in this work. Hydroforming is expected to greatly increase the formability of composite sheet by the use of a controllable heated, pressurized fluid. Hydroforming, in comparison with sheet stamping, is a more economical manufacturing process, since it does not require the use of a female die. The pressurized fluid acts as a support for the composite sheet throughout the forming process. A numerical analysis has been performed on this process in order to develop a method of predicting the final part geometry. The numerical analysis takes into account the pressurized fluid, the thermal effects, and the clamping mechanism used to hold the material in place as the part is formed. Numerical results show that using hydroforming for manufacturing glass fiber reinforced polypropylene composite material significantly reduces the strain, especially within the cup region of the hemispherical part. The fluid pressure also has an effect on the internal stresses of the part by allowing deeper draws before rupture. The experimentation, coupled with the prediction of the finite element modeling, indicates that the hydroforming of composite materials is a viable processing method that deserves more attention based on the significant advantages it provides in cost savings and part production accuracy.
Cautionary Aspects of Applied Probabilistics
Authors: Annis Charles 
Published: November 2021

Abstract
The idea of probabilistic engineering analysis — replacing fixed values for important parameters with their probability densities — seems almost self-evident. With the arrival of increasingly inexpensive computing capacity the past decade has witnessed a great proliferation of such analysis. Regrettably, however, much of this is unwittingly constructed on untenable statistical premises. Engineers, sure of their subsequent logic, can arrive at grossly erroneous conclusions, not always because their engineering is flawed, but because they relied on statistical assumptions that do not hold in their situation, or overlooked statistical results that do.
Probabilistic Micromechanical Fatigue Model for High Temperature Materials
Authors: Tryon Robert G. 
Published: November 2021

Abstract
The paper discusses an enhanced analytical modeling approach to characterize and understand fatigue crack initiation and growth in gas turbine engine intermetallics. It is recognized that the design of components subjected to fatigue cannot be based on average material behavior but that designs must consider −3σ or some other appropriate extreme value material properties. Thus, a life prediction capability useful in a design application must address the scatter inherent in material response to fatigue. The paper addresses the scatter in fatigue life of gamma titanium aluminide by investigating the microstructural variables responsible for the scatter and developing analytical and semi-analytical models to quantitatively relate the variables to the response. The model is general and considers the entire range of damage accumulation sequences; from crack nucleation of the initially unflawed structure to final fast fracture. However, the model also allows failure to be defined as any subset of damage accumulation i.e., crack initiation life to a particular crack size or the number of cycles to grow a crack from a particular size to final fracture. The models allows the structural engineer to systematically and quantitatively assess the influence of the material uncertainties on the overall reliability of the structure.
Functional Analysis of Bone-Biomaterial Interface
Authors: Tuan Rocky S. 
Published: November 2021

Abstract
Proper function and long-term stability of orthopaedic implants depend on the intimate association between bone cells and the implant biomaterial, a process known as osseointegration. Understanding the processes responsible for the establishment and maintenance of a functional bone-biomaterial interface and how these processes may be enhanced is crucial to the rational design and optimization of prosthetic devices. We have utilized cellular, molecular, and high-resolution imaging approaches to analyze the mechanistic basis of bone-biomaterial interactions. Specifically, we have characterized the initial adhesion of osteoblasts in terms of kinetics and relationship to the surface topography and chemistry of the biomaterials, particularly the cobalt-chrome and titanium alloys commonly used to fabricate orthopaedic prostheses. Results from these studies indicate that the long-term performance of osteoblasts adherent to biomaterials is crucially dependent on the characteristics of the initial adhesion step. Furthermore, osteoactive factors such as members of the transforming growth factor-β superfamily, including TGF-β1 and BMP-2, significantly enhance osteoblast cell adhesion. The molecular components responsible for the adhesion process include extracellular matrix proteins (e.g. fibronectin and collagen type I) and their cognate membrane receptors, the integrins. Our recent studies reveal that specific downstream, intracellular signaling events are also activated as a result of osteoblast adhesion, and that these signaling events are coupled to signal transduction mechanisms mediating growth factor activity. These events in combination regulate the continued expression and maintenance of the osteoblastic phenotype of the adherent cells, resulting in matrix maturation and mineralization, hallmarks of the bony tissue. Our current efforts focus on defining the target molecular pathways responsible for bone cell functioning on biomaterials, and the identification of critical biological and material parameters to optimize long-term osteoblast function and interaction with orthopaedically relevant biomaterials. The information gathered from these studies should provide a rational basis for the design of optimal implant biomaterials. (Supported in part by the NIH and the Annenberg Foundation)