Motor Unit Firing in the Human Anconeus During High Intensity Eccentric Contractions of Elbow Extensors

PURPOSE: To track single motor units through both isometric and eccentric elbow extensor contractions, at near maximal contraction intensity, and compare firing rates between contraction modes at an absolute torque. METHODS: Bipolar fine-wire electrodes were inserted into the anconeus in order to record motor unit firing behaviour during sets of high torque isometric and eccentric contractions. Contractions were performed on an isokinetic dynamometer at a pre-determined speed of 10°/s, through 60° total range of elbow joint motion, and at 50, 75 or 100% MVC. RESULTS: Mean motor unit firing rates were lower during eccentric contractions across all intensities (p \u3c 0.05), however surface EMG of the triceps brachii did not comprehensively follow the same pattern. CONCLUSION: Eccentric contraction is associated with an improvement in neuromechanical coupling in the anconeus, even at high torques. Previous studies have shown a similar effect but only at low to moderate contraction intensities

Leaping the hurdles in developing regenerative treatments for the intervertebral disc from preclinical to clinical

Chronic back and neck pain is a prevalent disability, often caused by degeneration of the intervertebral disc. Because current treatments for this condition are less than satisfactory, a great deal of effort is being applied to develop new solutions, including regenerative strategies. However, the path from initial promising idea to clinical use is frought with many hurdles to overcome. Many of the keys to success are not necessarily linked to science or innovation. Successful translation to clinic will also rely on planning and awareness of the hurdles. It will be essential to plan your entire path to clinic from the outset and to do this with a multidisciplinary team. Take advise early on regulatory aspects and focus on generating the proof required to satisfy regulatory approval. Scientific demonstration and societal benefits are important, but translation cannot occur without involving commercial parties, which are instrumental to support expensive clinical trials. This will only be possible when intellectual property can be protected sufficiently to support a business model. In this manner, commercial, societal, medical, and scientific partners can work together to ultimately improve patient health. Based on literature surveys and experiences of the co‐authors, this opinion paper presents this pathway, highlights the most prominent issues and hopefully will aid in your own transational endeavors

Cape town urban development index a rubric for urban transformation

The City of Cape Town has been working towards understanding the intricate relationship between land-use and transportation in order to develop growth management strategies that seek to create a more balanced travel demand profile of the city over time by enabling a better spatial relationship between trip producing and trip attracting land-uses. The City produced the TOD Strategic Framework in 2016, the revised Integrated Development Plan in 2017 and the new Municipal Spatial Development Framework in 2018 all of which emphasise the need for Spatial Transformation. An important question then arises from this which is: The City has aligned its key policies, strategies and priorities towards urban and spatial transformation but how do we know that the implementation of these is effective and what should we measure to assess this? The Urban Development Index (UDI) was conceived as a mechanism to answer this question but also to enable the identification of future transformation priorities. The Cape Town UDI builds on the previously developed Transport Development Index (TDI) by adding spatially disaggregated indices relating to land-use diversity, residential and employment density in public transport corridors, housing price diversity and informality ratios in the City. Eleven indices covering transport, land-use and housing were defined to measure the different facets of spatial and urban transformation.Papers presented virtually at the 39th International Southern African Transport Conference on 05 -07 July 202

Life history of Elizabeth Stolworthy Jolley

Typescript of a biographical sketch of Elizabeth Stolworthy Jolley, from an interview. She was born in Salt Lake City, Utah, in 1858, and the family soon settled at Parowan, later moving to Mount Carmel and Orderville. After her marriage, she and husband moved to Tropic. Typed by Layton J. Ott in 193

Pediatric cervical spine fracture case report: Best practice to delay transition to rear-facing restraint

Pediatric physicians and motor vehicle safety experts have been advocating for change in child passenger restraint practices for decades. As professional recommendations evolve to support extended rear-facing restraint, actual practices remain disparate. We report a case of pediatric cervical spine fracture due to motor vehicle collision, an uncommon, yet predictable, pattern of injury for which prevention education is undoubtedly preferable to managing the consequences of premature forward-facing in vulnerable pediatric patients. Currently, 9 kg is a minimum legal standard for forward-facing child restraint system use in Ontario, rather than a recommended transition time. We advise that parents should be counselled on the benefits of rear-facing as long as possible and discuss realistic transition times using their child restraint system manual as a reference, with the goal of approaching, but not exceeding, the maximum weight, height and fit requirements for optimal safety

Predicting Rate-dependent Lumbar Spine Biomechanics: Range of Motion, Neutral Zone, Stiffness, and Hysteresis

INTRODUCTION: The primary source for our current understanding on spine segment biomechanics continues to be cadaveric testing. However, the vast majority of this testing has been conducted at very slow rates (quasistatic) at room temperature. All of the tissues of the spine have been shown to exhibit sensitivity to these parameters. Thus, the purpose of this study was to characterize the segmental flexibility of the lumbar spine with respect to bending rates over the voluntary range at both body temperature and room temperature. METHODS: Biomechanical flexibility testing was performed at 21 distinct bending rates on 27 lumbar FSUs following an IRB approved acquisition and testing protocol. Applied bending rates ranged from 0-to 14-˚/sec in flexion-extension to loads of 7.5(±0.3)-Nm at either body temperature (37±3 ˚C) or room temperature (20±3 ˚C). Flexibility testing quantified segmental range of motion (ROM), neutral zone (NZ), stiffness (K), and hysteresis area (H) [1], as described in The torque-rotation response for each segment was captured following a preconditioning routine and fit ( ̅̅̅̅ = 0.99) with two dual inflection-point Boltzmann curves using a least squares method. A dataset normalized about the 1-˚/sec control speed was used to generate a predictive model of the torque-rotation response of spinal segments based on bending rate. Predicted values for ROM, NZ, K, and H were compared to actual values using a Bland-Altman analysis. RESULTS: ROM was determined to be the only DIP-Boltzmann parameter significantly affected (p<0.0001) by the loading rate (i.e., the remaining parameters were not affected by rate). Hence, the predictive model The Bland-Altman analysis of 264 samples DISCUSSION: The bending rate dependence of the lumbar spine is consistent with previous non-human segmental studies (e.g., [4]). The predictive model presented in the current work allows for straightforward estimation of spinal segment torque-rotation behavior at rates spanning the range of voluntary motion based on determination of the response at a single bending rate. The Bland-Altman analysis confirms that the model is accurate for the included datasets, however validation of the model on an independent dataset was beyond the scope of the present work. Rate effects have usually been ignored in numerical models and medical device design, however the present work demonstrates that care should be given to extrapolating cadaveric testing results to the in vivo situation. SIGNIFICANCE: Bending rate and temperature significantly alter spinal flexibility. However, these effects can easily be accounted for using the predictive model described in the present work (Equation 2). ACKNOWLEDGMENTS

A Short Sketch of the life of the parents of H. T. Stolworth

Typescript of a sketch biography of Thomas and Matilda Stolworthy, Mormon pioneers who lived in various parts of Utah. Dictated by their son, Henry Thomas Stolworthy to Lucy S. Burnham. Typed by Layton J. Ott in 193

Biomechanical analysis of the camelid cervical intervertebral disc

Chronic low back pain (LBP) is a prevalent global problem, which is often correlated with degenerative disc disease. The development and use of good, relevant animal models of the spine may improve treatment options for this condition. While no animal model is capable of reproducing the exact biology, anatomy, and biomechanics of the human spine, the quality of a particular animal model increases with the number of shared characteristics that are relevant to the human condition. The purpose of this study was to investigate the camelid (specifically, alpaca and llama) cervical spine as a model of the human lumbar spine. Cervical spines were obtained from four alpacas and four llamas and individual segments were used for segmental flexibility/biomechanics and/or morphology/anatomy studies. Qualitative and quantitative data were compared for the alpaca and llama cervical spines, and human lumbar specimens in addition to other published large animal data. Results indicate that a camelid cervical intervertebral disc (IVD) closely approximates the human lumbar disc with regard to size, spinal posture, and biomechanical flexibility. Specifically, compared with the human lumbar disc, the alpaca and llama cervical disc size are approximately 62%, 83%, and 75% with regard to area, depth, and width, respectively, and the disc flexibility is approximately 133%, 173%, and 254%, with regard to range of motion (ROM) in axial-rotation, flexion-extension, and lateral-bending, respectively. These results, combined with the clinical report of disc degeneration in the llama lower cervical spine, suggest that the camelid cervical spine is potentially well suited for use as an animal model in biomechanical studies of the human lumbar spine