Before initiating a walking movement, the central nervous system forms a motor plan, a set of motor commands predicted to accomplish task-specific goals. To be effective, motor plans must be continually updated to consider an ever-changing external environment. Despite being an inherent part of walking, how the nervous system adapts...
Myoelectric pattern recognition-based upper limb prostheses measure electromyographic (EMG) signals from the residual limb and learn to identify muscle activity patterns that correspond to intended gestures. To train an accurate pattern recognition controller, it is essential that the training signals typify signals measured in real-world scenarios. When these conditions are...
Stairs and curbs often present as an exhausting environmental barrier for individuals with bilateral cerebral palsy (CP) due to their lower limb motor impairments. Indeed, performance in stair-climbing in this population has a higher correlation with disruption of mobility than walking. Community members affected by CP consider impaired mobility a...
Like many diseases, atherosclerotic cardiovascular disease is driven by the activity of inflammatory cells. Using molecular imaging to target and analyze populations of inflammatory cells is one promising strategy to non-invasively assess atherosclerosis progression. However, current molecular imaging contrast agents are not suited for such targeted imaging applications. Nanomaterial-based strategies...
Everyday tasks, such as putting on a jacket or reaching up to a shelf, often become more challenging for older adults. These tasks rely on the ability to generate three-dimensional torques about the shoulder and to adapt these torques across activities. Shoulder strength and muscle coordination impact shoulder torque production,...
The current view in neuroscience holds that the brain, together with its sensory and motor structures and the environment, form a closed-loop system – a sensorimotor loop – in which the brain receives information from the environment and converts it into a motor response while simultaneously making predictions about future...
Each neuron in the primary motor cortex (M1) is like a musician in an orchestra, contributing to a larger harmony under the constraint of a “neural manifold”—a geometric score describing the correlated signals produced by the neural musicians that drive movement. Despite the widespread recognition of the importance of M1...
Radiofrequency ablation is a minimally-invasive treatment method that aims to destroy undesired tissue by exposing it to alternating current in the 100 kHz to 800 kHz frequency range and heating it until it is destroyed via coagulative necrosis. Ablation treatment is gaining momentum especially in cancer research, where the undesired...
The dynamics of human joints are fundamental characteristic of the human motor system, and altered joint impedance can hinder mobility. Individuals with transtibial amputation typically experience slower and energetically costly gait, while individuals with chronic stroke experience persisting gait deficits arising from spasticity, hypertonia and paresis. Investigating joint impedance of...
A stroke occurs when blood flow in the brain is impaired and often causes damage to corticospinal tract projections that control the muscles of the upper-extremity. Due to this damage, 50-70% of stroke survivors experience long-term upper-extremity functional deficits(Faria-Fortini, Michaelsen, Cassiano, & Teixeira-Salmela, 2011). These deficits result from motor impairments...
Bioelectronic devices at the biotic/abiotic interface face a number of key challenges that include device degradation when exposed to biological fluid, their elicited immune response due to mechanical mismatch, and poor signal transduction. Organic electronic materials and their devices, such as organic electrochemical transistors (OECTs) address these shortcomings. They can...
4D Flow MRI is a phase-contrast magnetic resonance imaging method that enables direct measurement of velocities in three orthogonal directions throughout the heartbeat. This permits direct quantification of hemodynamic parameters, including flow, mean velocity, peak velocity, and pulsatility, for individual cerebral vessels. Despite ongoing research into neurovascular applications of 4D...
Wireless power strategies are critical to system level implementation of bio-integrated devices. To achieve mechanically robust, manufacturable systems, batteries are often integrated as an on-board power source to support sensing, wireless communication and signal conditioning. Unfortunately, most sources of battery power use hazardous and environmentally harmful materials, which frustrate incorporation...
The goal of the work reported here was to answer two important questions with regards to LTVV use for patients with ARDS: 1) How do we measure adoption? and 2) What are the drivers of provider adoption? To this end, I have demonstrated the influence of patient height, hypoxemia severity,...
Chromatin, a complex nuclear structure comprised of DNA, histones, RNA, and other nuclear proteins, is one of the most critical components within the cell because it houses the genetic information and its organization regulates important cellular functions, such as transcription, replication, and repair. Its structural organization is well understood at...
Vimentin intermediate filaments (VIFs) provide mechanical integrity to cells and serve as markers of tissue origin and cell differentiation. Several non-mechanical roles for vimentin have recently been reported, including regulation of key pathways that control cell growth, cell signaling, and cell motility. Here, I present the role of vimentin in...
Magnetic resonance imaging (MRI) is used widely and frequently in the clinical setting to image and diagnose patients. In addition to the anatomical scans that can be acquired using MRI, different kinds of physiological parameters, such as blood flow, can be obtained by utilizing pulse sequence, scan protocol and post-processing....
Ankle sprains are the most common musculoskeletal injury. After an ankle sprain, about 40% of individuals develop Chronic Ankle Instability (CAI), resulting in recurrent sprains, the ankle giving way, or feelings of instability. Most sprains occur due to excess inversion of the ankle. Frontal-plane ankle stiffness quantifies the ankle’s ability...
Proprioception, or the sense of one’s body in space, provides critical feedback that the brain usesto generate controlled movements. When proprioceptive feedback is lost, people find it difficult
to perform even basic motor tasks. Despite its importance, proprioceptive coding of single
neurons in the cuneate nucleus (CN), the most peripheral...
The last decade has witnessed a rapid transformation in our understanding of the structure of chromatin, the nuclear complex of DNA and its structural proteins. While, barring mutations, the DNA sequence in each cell of the human body is the same, it is the structure of the chromatin complex that...