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Full-Text Articles in Engineering

Compact Low-Cost Fiberless Diffuse Speckle Contrast Flow-Oximeter, Guoqiang Yu, Chong Huang, J. Todd Hastings Nov 2020

Compact Low-Cost Fiberless Diffuse Speckle Contrast Flow-Oximeter, Guoqiang Yu, Chong Huang, J. Todd Hastings

Biomedical Engineering Faculty Patents

A low-cost compact fiberless diffuse speckle contrast flow-meter includes a small laser diode and a 2-dimensional imaging device such as a charge coupled device (CCD) or complementary metal oxide semiconductor (CMOS) for directly contacting the tissue and measuring a parameter such as blood flow in a deep/thick volume of tissue (up to 10 mm depth). The small laser diode is fixed at a certain distance (0 to 20 mm) from the imaging device and directly contacts the tissue. Light emitted from the laser diode penetrates through the tissue and reflects back to the imaging device without passing through any lenses …


Cardiorespiratory Fitness Diminishes The Effects Of Age On White Matter Hyperintensity Volume, Nathan F. Johnson, Ahmed A. Bahrani, David K. Powell, Gregory A. Jicha, Brian T. Gold Aug 2020

Cardiorespiratory Fitness Diminishes The Effects Of Age On White Matter Hyperintensity Volume, Nathan F. Johnson, Ahmed A. Bahrani, David K. Powell, Gregory A. Jicha, Brian T. Gold

Physical Therapy Faculty Publications

White matter hyperintensities (WMHs) are among the most commonly observed marker of cerebrovascular disease. Age is a key risk factor for WMH development. Cardiorespiratory fitness (CRF) is associated with increased vessel compliance, but it remains unknown if high CRF affects WMH volume. This study explored the effects of CRF on WMH volume in community-dwelling older adults. We further tested the possibility of an interaction between CRF and age on WMH volume. Participants were 76 adults between the ages of 59 and 77 (mean age = 65.36 years, SD = 3.92) who underwent a maximal graded exercise test and structural brain …


Near Simultaneous Laser Scanning Confocal And Atomic Force Microscopy (Conpokal) On Live Cells, Joree N. Sandin, Surya P. Aryal, Thomas E. Wilkop, Christopher I. Richards, Martha E. Grady Aug 2020

Near Simultaneous Laser Scanning Confocal And Atomic Force Microscopy (Conpokal) On Live Cells, Joree N. Sandin, Surya P. Aryal, Thomas E. Wilkop, Christopher I. Richards, Martha E. Grady

Physiology Faculty Publications

Techniques available for micro- and nano-scale mechanical characterization have exploded in the last few decades. From further development of the scanning and transmission electron microscope, to the invention of atomic force microscopy, and advances in fluorescent imaging, there have been substantial gains in technologies that enable the study of small materials. Conpokal is a portmanteau that combines confocal microscopy with atomic force microscopy (AFM), where a probe "pokes" the surface. Although each technique is extremely effective for the qualitative and/or quantitative image collection on their own, Conpokal provides the capability to test with blended fluorescence imaging and mechanical characterization. Designed …


Changes In Lumbo-Pelvic Coordination Of Individuals With And Without Low Back Pain When Wearing A Hip Orthosis, Matthew T. Ballard, Colin Drury, Babak Bazrgari Jul 2020

Changes In Lumbo-Pelvic Coordination Of Individuals With And Without Low Back Pain When Wearing A Hip Orthosis, Matthew T. Ballard, Colin Drury, Babak Bazrgari

Biomedical Engineering Faculty Publications

Individuals with low back pain demonstrate an abnormal lumbo-pelvic coordination compared to back-healthy individuals. This abnormal coordination presents itself as a reduction in lumbar contributions and an increase in pelvic rotations during a trunk forward bending and backward return task. This study investigated the ability of a hip orthosis in correcting such an abnormal lumbo-pelvic coordination by restricting pelvic rotation and, hence increasing lumbar contributions. The effects of the hip orthosis on the lumbo-pelvic coordination were investigated in 20 low back pain patients and 20 asymptomatic controls. The orthosis reduced pelvic rotation by 12.7° and increased lumbar contributions by 11%. …


Β-Amyloid And Tau Drive Early Alzheimer's Disease Decline While Glucose Hypometabolism Drives Late Decline, Tyler C. Hammond, Xin Xing, Chris Wang, David Ma, Kwangsik Nho, Paul K. Crane, Fanny Elahi, David A. Ziegler, Gongbo Liang, Qiang Cheng, Lucille M. Yanckello, Nathan Jacobs, Ai-Ling Lin Jul 2020

Β-Amyloid And Tau Drive Early Alzheimer's Disease Decline While Glucose Hypometabolism Drives Late Decline, Tyler C. Hammond, Xin Xing, Chris Wang, David Ma, Kwangsik Nho, Paul K. Crane, Fanny Elahi, David A. Ziegler, Gongbo Liang, Qiang Cheng, Lucille M. Yanckello, Nathan Jacobs, Ai-Ling Lin

Sanders-Brown Center on Aging Faculty Publications

Clinical trials focusing on therapeutic candidates that modify β-amyloid (Aβ) have repeatedly failed to treat Alzheimer’s disease (AD), suggesting that Aβ may not be the optimal target for treating AD. The evaluation of Aβ, tau, and neurodegenerative (A/T/N) biomarkers has been proposed for classifying AD. However, it remains unclear whether disturbances in each arm of the A/T/N framework contribute equally throughout the progression of AD. Here, using the random forest machine learning method to analyze participants in the Alzheimer’s Disease Neuroimaging Initiative dataset, we show that A/T/N biomarkers show varying importance in predicting AD development, with elevated biomarkers of Aβ …


A Comparative Study Of Sleep And Diurnal Patterns In House Mouse (Mus Musculus) And Spiny Mouse (Acomys Cahirinus), Chanung Wang, Lauren E. Guerriero, Dillon M. Huffman, Asma'a A. Ajwad, Trae C. Brooks, Sridhar Sunderam, Ashley W. Seifert, Bruce F. O'Hara Jul 2020

A Comparative Study Of Sleep And Diurnal Patterns In House Mouse (Mus Musculus) And Spiny Mouse (Acomys Cahirinus), Chanung Wang, Lauren E. Guerriero, Dillon M. Huffman, Asma'a A. Ajwad, Trae C. Brooks, Sridhar Sunderam, Ashley W. Seifert, Bruce F. O'Hara

Biomedical Engineering Faculty Publications

Most published sleep studies use three species: human, house mouse, or Norway rat. The degree to which data from these species captures variability in mammalian sleep remains unclear. To gain insight into mammalian sleep diversity, we examined sleep architecture in the spiny basal murid rodent Acomys cahirinus. First, we used a piezoelectric system validated for Mus musculus to monitor sleep in both species. We also included wild M. musculus to control for alterations generated by laboratory-reared conditions for M. musculus. Using this comparative framework, we found that A. cahirinus, lab M. musculus, and wild M. musculus were …


Small Molecule Drug Release Form In Situ Forming Degradable Scaffolds Incorporating Hydrogels And Bioceramic Microparticles, David A. Puleo, Todd A. Milbrandt, J. Zach Hilt, Paul Fisher, Vishwas Talwalkar Jun 2020

Small Molecule Drug Release Form In Situ Forming Degradable Scaffolds Incorporating Hydrogels And Bioceramic Microparticles, David A. Puleo, Todd A. Milbrandt, J. Zach Hilt, Paul Fisher, Vishwas Talwalkar

Biomedical Engineering Faculty Patents

The present invention relates to an injectable system combining a hydrogel, a bioceramic and a degradable matrix that provides for sustained drug delivery and structural support to recovering tissue, such as bone and the periodontium.


Brain Structure Changes Over Time In Normal And Mildly Impaired Aged Persons, Charles D. Smith, Linda J. Van Eldik, Gregory A. Jicha, Frederick A. Schmitt, Peter T. Nelson, Erin L. Abner, Richard J. Kryscio, Richard R. Murphy, Anders H. Andersen May 2020

Brain Structure Changes Over Time In Normal And Mildly Impaired Aged Persons, Charles D. Smith, Linda J. Van Eldik, Gregory A. Jicha, Frederick A. Schmitt, Peter T. Nelson, Erin L. Abner, Richard J. Kryscio, Richard R. Murphy, Anders H. Andersen

Neurology Faculty Publications

Structural brain changes in aging are known to occur even in the absence of dementia, but the magnitudes and regions involved vary between studies. To further characterize these changes, we analyzed paired MRI images acquired with identical protocols and scanner over a median 5.8-year interval. The normal study group comprised 78 elders (25M 53F, baseline age range 70-78 years) who underwent an annual standardized expert assessment of cognition and health and who maintained normal cognition for the duration of the study. We found a longitudinal grey matter (GM) loss rate of 2.56 ± 0.07 ml/year (0.20 ± 0.04%/year) and a …


Barn-Raising On The Digital Frontier: The L.A.U.N.C.H. Collaborative, Bradford W. Hesse, David Ahern, Michele Ellison, Eliah Aronoff-Spencer, Robin C. Vanderpool, Karen Onyeije, Michael C. Gibbons, Timothy W. Mullett, Ming-Yuan Chih, Victoria Attencio, Grant Patterson, Jessica Boten, Christopher Hartshorn, Ben Bartolome, Katie Gorscak, Melanie Mccomsey, Alexandra Hubenko, Bin Huang, Corey Baker, Don Norman Jan 2020

Barn-Raising On The Digital Frontier: The L.A.U.N.C.H. Collaborative, Bradford W. Hesse, David Ahern, Michele Ellison, Eliah Aronoff-Spencer, Robin C. Vanderpool, Karen Onyeije, Michael C. Gibbons, Timothy W. Mullett, Ming-Yuan Chih, Victoria Attencio, Grant Patterson, Jessica Boten, Christopher Hartshorn, Ben Bartolome, Katie Gorscak, Melanie Mccomsey, Alexandra Hubenko, Bin Huang, Corey Baker, Don Norman

Journal of Appalachian Health

A meta-analysis of oncology papers from around the world revealed that cancer patients who lived more than 50 miles away from hospital centers routinely presented with more advanced stages of disease at diagnosis, exhibited lower adherence to prescribed treatments, presented with poorer diagnoses, and reported a lower quality of life than patients who lived nearer to care facilities. Connected health approaches—or the use of broadband and telecommunications technologies to evaluate, diagnose, and monitor patients beyond the clinic—are becoming an indispensable tool in medicine to overcome the obstacle of distance.


A Framework For Heterologous Biosynthesis Of Natural Products In Mammalian Cells Via Polymer-Mediated Transfections, Logan Warriner Jan 2020

A Framework For Heterologous Biosynthesis Of Natural Products In Mammalian Cells Via Polymer-Mediated Transfections, Logan Warriner

Theses and Dissertations--Chemical and Materials Engineering

With the promise to treat a multi-faceted list of serious inherited and acquired diseases, such as cancer, neurodegenerative and infectious diseases, and inherited genetic indications, gene therapy has continued to push the boundaries of traditional medicine since its earliest implementation. While much progress has been made, clinical success has largely remained elusive. Immunogenicity, difficulty producing commercially relevant quantities, and having a limited genetic payload still limits the ability of viruses to act as directed delivery agents for genetic material. As such, researchers have turned to cationic synthetic materials as a means of delivering nucleic acids, which can circumvent the immune …


Early Acid/Base And Electrolyte Changes In Permanent Middle Cerebral Artery Occlusion: Aged Male And Female Rats, Sarah R. Martha, Lisa A. Collier, Stephanie M. Davis, Sarah J. Goodwin, David Powell, Doug Lukins, Justin F. Fraser, Keith R. Pennypacker Jan 2020

Early Acid/Base And Electrolyte Changes In Permanent Middle Cerebral Artery Occlusion: Aged Male And Female Rats, Sarah R. Martha, Lisa A. Collier, Stephanie M. Davis, Sarah J. Goodwin, David Powell, Doug Lukins, Justin F. Fraser, Keith R. Pennypacker

Neurosurgery Faculty Publications

BACKGROUND: Early changes in acid/base and electrolyte concentrations could provide insights into the development of neuropathology at the onset of stroke. We evaluated associations between acid/base and electrolyte concentrations, and outcomes in permanent middle cerebral artery occlusion (pMCAO) model.

METHODS: 18-month-old male and female Sprague-Dawley rats underwent pMCAO. Pre-, post- (7 min after occlusion), and at 72 hr of pMCAO venous blood samples provided pH, carbon dioxide, oxygen, glucose, hematocrit, hemoglobin, and electrolyte values of ionized calcium, potassium, and sodium. Multiple linear regression determined predictors of infarct and edema volumes from these values, Kaplan-Meier curve analyzed morality between males and …


Assessment Of White Matter Hyperintensity, Cerebral Blood Flow, And Cerebral Oxygenation In Older Subjects Stratified By Cerebrovascular Risk, Ahmed A. Bahrani Jan 2020

Assessment Of White Matter Hyperintensity, Cerebral Blood Flow, And Cerebral Oxygenation In Older Subjects Stratified By Cerebrovascular Risk, Ahmed A. Bahrani

Theses and Dissertations--Biomedical Engineering

Objective: Cerebrovascular disease (CVD) is the fifth most common cause of mortality in the United States. Diagnosis of CVD at an early stage is critical for optimal intervention designed to prevent ongoing and future brain injury. CVD is commonly associated with abnormalities of the cerebral microvasculature leading to tissue dysfunction, neuronal injury and death, and resultant clinical symptoms, which in turn, further impacts cerebral autoregulation (CA). This series of studies aims to test the hypothesis that white matter hyperintensities (WMH) and cerebral hemodynamics (quantified by magnetic resonance imaging (MRI) and an by innovative hybrid near-infrared diffuse optical instrument) can be …


Noncontact Multiscale Diffuse Optical Imaging Of Deep Tissue Hemodynamics In Animals And Humans, Siavash Mazdeyasna Jan 2020

Noncontact Multiscale Diffuse Optical Imaging Of Deep Tissue Hemodynamics In Animals And Humans, Siavash Mazdeyasna

Theses and Dissertations--Biomedical Engineering

Blood flow (BF) impacts the delivery of oxygen and nutrients to tissues and the removal of metabolic byproducts from tissues. Imaging of BF distributions helps characterize many diseases associated with tissue hypoxia/ischemia. The purpose of this study was to develop and validate a novel, noninvasive, noncontact, high-density camera-based speckle contrast diffuse correlation tomography (scDCT) device for use in both animal and human studies. The scDCT uses a galvo-mirror to remotely deliver the focused point near-infrared light to source positions and a sensitive 2D camera to quantify spatial diffuse speckle fluctuations, resulting from the movement of red blood cells in deep …


Work Related Diurnal Changes In Trunk Mechanical Behavior, Maeve Mcdonald Jan 2020

Work Related Diurnal Changes In Trunk Mechanical Behavior, Maeve Mcdonald

Theses and Dissertations--Biomedical Engineering

The objectives of this study were to analyze effects of day-long exposure to LBP risk factors on lumbo-pelvic coordination (LPC) in nursing occupations and to verify if physical activity level affects diurnal work-related changes in LPC. Thirty-three nurses were recruited into three groups based on workplace physical demands and each completed two data collection sessions, one before and one after their 8-12 hour work shift. Participants completed several stationary trunk forward-bending/backward-return exercises at self-selected “fast” and “slow” rotational speeds, and while holding a 15 lbs. load. Kinematic data collected during these exercises were then used to characterize the timing and …


High Frequency Oscillations In The Epileptic Brain: Accurate Detection, Effect Of Vigilance State, And Sample Size Considerations, Amir Fared Partu Al-Bakri Jan 2020

High Frequency Oscillations In The Epileptic Brain: Accurate Detection, Effect Of Vigilance State, And Sample Size Considerations, Amir Fared Partu Al-Bakri

Theses and Dissertations--Biomedical Engineering

About a third of all epilepsy patients may experience seizures that are resistant to medication. Surgical resection may be an option for some of these patients, but localization of the epileptogenic zone is difficult and expensive. For this process, the seizures must be observed and recorded in a clinical setting over several days. High-frequency oscillations (HFOs) have emerged as a possible biomarker for predicting the epileptogenic zone from a brief interictal recording of brain electrical activity without having to wait for seizures. The broad objective of this dissertation is to devise methods and criteria for accurate detection, sampling and localization …


Atv Dynamics And Pediatric Rider Safety, James T. Auxier Ii Jan 2020

Atv Dynamics And Pediatric Rider Safety, James T. Auxier Ii

Theses and Dissertations--Biomedical Engineering

It has been observed through numerous academic and governmental agency studies that pediatric all-terrain vehicle ridership carries significant risk of injury and death. While no doubt valuable to safety, the post-hoc approach employed in these studies does little to explain the why and how behind the risk factors. Furthermore, there has been no prolonged, widespread, organized, and concerted effort to reconstruct and catalog the details and causes of the large (20,000+) number of ATV-related injuries that occur each year as has been done for road-based motor vehicle accidents. This dissertation takes the opposite approach from a meta-analysis and instead examines …


Effects Of A Hip Orthosis On Lumbopelvic Coordination In Individuals With And Without Low Back Pain, Colin Drury Jan 2020

Effects Of A Hip Orthosis On Lumbopelvic Coordination In Individuals With And Without Low Back Pain, Colin Drury

Theses and Dissertations--Biomedical Engineering

Individuals with low back pain (LBP) demonstrate an abnormal lumbopelvic coordination compared to back-healthy individuals. This abnormal coordination presents itself as a reduction in lumbar contribution and an increase in pelvic contribution to trunk motion. This study investigated the ability of a hip orthosis to correct such an abnormal lumbo-pelvic coordination by restricting pelvic rotation and, as a result, increasing lumbar contributions. The effects of the hip orthosis on the magnitude and timing characteristics of lumbopelvic coordination were investigated in 20 patients with LBP and 20 asymptomatic controls. The orthosis significantly increased lumbar contributions by 11%, 5.42%, 4.84%, and 4.89% …


Knee Joint Loading Following Anterior Cruciate Ligament Reconstruction: Link To Patient Reported Outcomes And A Novel Method To Monitor With Wearable Sensors, Alex Spencer Jan 2020

Knee Joint Loading Following Anterior Cruciate Ligament Reconstruction: Link To Patient Reported Outcomes And A Novel Method To Monitor With Wearable Sensors, Alex Spencer

Theses and Dissertations--Kinesiology and Health Promotion

Recovery from anterior cruciate ligament reconstruction (ACLR) commonly results in undesirable physical and patient-reported outcomes (PROs). Identification of modifiable factors such as knee contact force (KCF) early in rehabilitation that can improve these outcomes is important due to the rapid decrease in function, quality of life, and joint health in this population. Additionally, if noninvasive measurement of KCFs outside of a traditional laboratory were possible, clinicians could optimize patient treatment with personalized care. Therefore, there are two primary aims to this thesis: 1) quantify the link between KCF and PROs which measure pain, ability to perform activities of daily living, …


Bacterial Cell Wall Characterization Via Atomic Force And Confocal Microscopy, Joree Sandin Jan 2020

Bacterial Cell Wall Characterization Via Atomic Force And Confocal Microscopy, Joree Sandin

Theses and Dissertations--Mechanical Engineering

Poor oral hygiene is a severe global health issue, with about 44% of the Earth’s population suffering from untreated tooth decay, accounting for over $100 billion dollars spent on dental services per year in the United States, alone. Manual treatments, such as brushing, flossing, or swishing with antiseptic rinse are the main ways to alleviate harmful bacteria that cause these oral health problems. Streptococcus mutans (S. mutans) is a group of highly antibiotic, Gram-positive bacteria that heavily contribute to oral cavities, plaque build-up, and potential loosening or loss of dental implants if a biofilm develops. Currently, the mechanism …