• The Feasibility of Wearable Sensors for the Automation of Distal Upper Extremity Ergonomic Assessment Tools

  Cousins, Daniel; Applied Health Sciences Program

  Work-related distal upper limb musculoskeletal disorders are costly conditions that many companies and researchers spend significant resources on preventing. Ergonomic assessments evaluate the risk of developing a work-related musculoskeletal disorder (WMSD) by quantifying variables such as the force, repetition, and posture (among others) that the task requires. Accurate and objective measurements of force and posture are challenging due to equipment and location constraints. Wearable sensors like the Delsys Trigno Quattro combine inertial measurement units (IMUs) and surface electromyography to solve collection difficulties. The purpose of this work was to evaluate the joint angle estimation of IMUs and the relationship between sEMG and overall task intensity throughout a controlled wrist motion. Using a 3 degrees-of-freedom wrist manipulandum, the feasibility of a small, lightweight wearable was evaluated to collect accurate wrist flexion and extension angles and to use sEMG to quantify task intensity. The task was a repeated 95º arc in flexion/ extension with six combinations of wrist torques and grip requirements. The mean wrist angle difference (throughout the range of motion) between the WristBot and the IMU of 1.70° was not significant (p= 0.057); but significant differences existed throughout the range of motion. The largest difference between the IMU and the WristBot was 10.7° at 40° extension; this discrepancy is smaller than typical visual inspection joint angle estimate errors by ergonomists of 15.6°. All sEMG metrics (flexor muscle root mean square (RMS), extensor muscle RMS, mean RMS, integrated sEMG (iEMG), physiological cross-sectional area weighted RMS) and ratings of perceived exertion (RPE) had significant regression results with the task intensity. Variance in RPE was better explained by task intensity than the best sEMG metric (iEMG) with R2 values of 0.35 and 0.21, respectively. Wearable sensors can be used in occupational settings to increase the accuracy of postural assessments; additional research is required on relationships between sEMG and task intensity to be used effectively in ergonomics. There is potential for sEMG to be a powerful tool; however, the dynamic nature and combined exertion (grip and flexion/ extension) make it difficult to quantify task intensity
• Medieval Acts from Normandy, 1308 and 1365

  Cameron, Chantal (2023-01-25)

  A pair of two 14th century Latin medieval acts from the Normandy region in France, handwritten on parchment in the years 1308 and 1365, from the reigns of Philip IV and Charles V of France. The charters have been stitched together. There is a small signum at the end of the first charter, and a larger, ornate signum at the end of the second. These charters have been written in a 34-line and 25-line format.
• Medieval Act for Gilles Dabelain, July 12, 1445.

  Cameron, Chantal (2023-01-25)

  Medieval Act for one Gilles Dabelain, July 12, 1445. Two Manuscripts on Parchment. A mid-15th century medieval act, written in French and on parchment, being an original copy of the act sanctioning the division of Gilles Dabelain’s property between his children Hues and Jehanne, the latter being the wife of Jehan de Lannoy, written in the city of Lille, France, July 12, 1445. Attached to the act is a smaller, accompanying manuscript on parchment. There are three original seals at the end. The primary manuscript has been written in a 105-line format, and the attached manuscript an 18-line format.
• Medieval Charter, 1281

  Cameron, Chantal (2023-01-25)

  A late 13th century Latin medieval charter from Spain, handwritten on parchment in the year 1281, from the reign of Alfonso X of Castile. There is a charming signum at the end of the manuscript. This charter has been written in a 15 line format.
• Using Persistent Homology for Topological Analysis of Protein Interaction Network of Candida Antarctica Lipase B Molecular Dynamic Simulation Model

  Tajik, Samin; Department of Physics

  In this work, we aim to examine the activity of one of the most efficient and commonly used lipases, Candida Antarctica Lipase B (CalB), from the perspective of multiple computational techniques. To this end, we first conduct a series of Molecular Dynam- ics Simulations on CalB in different conditions to analyze the conformational changes of the protein and probe its unusual high-temperature activity. Next, we build the protein interaction network of amino acids for CalB to study pairwise interactions between amino acids (nodes) and probe the protein in terms of statistical features of links’ distribution. Finally, we employ an algebraic topology-based method to study the protein interaction network from a broader perspective. The ”Persistent Homol- ogy (PH) method” is then presented as a way to exceed pairwise interactions and examine protein networks in terms of patterns of interaction between the nodes. Per- sistent Homology studies the evolution of the protein interaction network’s topologi- cal features (homology groups) in different states. Employing topological analysis, we compare the active form of CalB at high temperatures to its inactive states to account for possible topological contributions to the protein functionality. By discovering a prominent 1-dimensional hole in the active form of the protein, we highlight the role of higher-order interaction patterns in the network. Moreover, using the evolution of topological features, we study topological changes in protein networks and show the decline in the total number of 1-dimensional features as the protein loses activity and compactness over time. Accordingly, we propose that the protein’s general conforma- tional changes and three-dimensional structure are not the only facets contributing to its active state. Instead, we suggest examining the topology of the protein inter- action network, referred to as different dimensional holes of the networks, as a higher dimensional analysis should be used to account for protein functionality. Hence, in this work, we desire to present that one needs to consider topological features acting as patterns of interaction between the components to study, examine or predict the folding of polypeptide chains into active structures.

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