Design of Novel Experiments and Analyses for Head and Spine Trauma Biomechanics

Previous biomechanics research studies have used both whole-body and isolated postmortem human surrogate experiments to define human injury tolerances, advance safety in injury producing environments, and promulgate standards for design of injury mitigating systems. Recent developments in transportation and sports-related fields have led to an increasing need to determine tolerances for combined loading (multi-axis) scenarios. This dissertation demonstrates the efficacy of the novel experimental design and analysis to head and spine trauma in these modalities. The first topic was the design of a novel experiment to examine the effect oblique loading on the tension tolerance of the lumbar spine. To examine this injury tolerance, isolated lumbosacral spine experiments were used with a custom six degree-of-freedom spinal alignment device. The isolated experiment injury matched previous whole-body tests and failure kinetics were obtained. The second topic was the design of a novel experiment to measure the response of the head and neck to off axis moment loading at the occipital condyle joint. A dynamic rotational system applied angular displacement centered at the OC joint in an orientation that resulted in combined flexion-extension/lateral-bending/and axial rotation of the head. Region-specific anatomic kinetics were determined using load cells and a motion capture system. The third topic was the design of a novel experiment model to assess the accuracy of wearable sensors for concussion research. The goal of this topic was to design a new technique which placed a custom sensor near the head-center-of-gravity in whole-body and isolated head/head-neck PMHS. Tests were conducted to benchmark current wearable sensors in the sport and military environments. The measured head kinematics from the in-PMHS sensor serves as the gold standard for these tests. The fourth topic was design of a novel technique to compute three-dimensional time-varying global response kinematics of the head, spine, and pelvis in oblique frontal impacts. Collected data were combined to create three-dimensional temporal global kinematic corridors which are needed to validate current and future finite element models of the components/subsystems, human body models, and they can also be used for benchmarking different computational models

FROM THE ITALIAN CHAMPIONSHIP TO THE PARALYMPIC PODIUM: ELABORATION OF A NOVEL APPROACH OF DRY-LAND TRAINING IN ÉLITE SWIMMERS WITH DISABILITY

The present Ph D. thesis describes the longitudinal evolution of the physical, postural and functional parameters of three top-level Paralympic swimmers (classes S9-SB8-SM9, S7-SB6-SM7, S5-SB4-SM5) during two years of training promoting a novel approach of \u201cdry land\u201d training based on quality of movement. It is divided into three sections. PART I: in according to available literature, it is described the importance to shift the focus from a movement expressed in quantity (the parameters evaluated are basically related on the athlete\u2019s fitness level) to a movement quality which means a more economic, efficient, biomechanically correct motion and their related assessments procedures. The foundations of human movement patterns are posture and breathing. PART II: two studies, based on aspects that have been an important part to the Paralympic swimmer\u2019s training method, are exposed. The aim of the first research was to evaluate the difference between traditional core training and the abdominal training corrected by diaphragmatic breathing pattern on abdominal fitness, quality of movement and pulmonary function during 4 weeks of training, in two groups (N=32; 29\ub13 years): the Experimental Group performed abdominal exercises characterized on muscular chain stretching accompanied by a diaphragmatic breathing pattern with vocal sound emission, conversely Traditional Group performed traditional core exercises like crunches or isometric planks. The purpose of the second study is to show a different modality of strength training without external devices which effects are similar to those obtained with Blood Flow Restriction Resistance Training. This method is characterized by the modulation of muscle action velocity using moderate intensities (low loads) and slow speed without pause between repetitions nor between phases. PART III: The aim is to show the longitudinal evolution three \ue8lite Paralympic swimmers during two years of training. Methods: related to their disability each subject underwent a specific dry-land training comprising a diaphragmatic breathing technique, aimed to improve their body alignment, mobility and trunk stabilization, as well as a slow-velocity resistance training aimed to improve their muscle strength. They were tested for functional movement by using FMSTM tests, a morphological analysis to describe their body posture, a MARM evaluation for the breathing patterns and the strength measured by vertical jump test with the infrared device Optojump. All data were collected over two years, from the Paralympic games in London in August 2012 to the IPC European Championship in Eindhoven in August 2014. Results: all swimmers improved both the single and the composite scores of the FMSTM assessment, indicating the achievement of a better postural control. They ameliorate their body alignment reaching a better balance between thoracic and diaphragmatic breathing pattern. The male athlete, also increased his strength parameters showing a +14% from December 2012 to August 2013 and an additional 2.6% from August 2013 to August 2014. All athletes won medals (silver and bronze ones) in the major international competitions, especially the male athlete won two bronze medals in London 2012, ended up five gold medals in Eindhoven 2014. Conclusion: These results show that a two-year specific dry-land training comprising body balance, breathing, and slow-velocity resistance training is capable of enhancing the functional, postural and strength performance of three top-level Paralympic swimmers. We conclude that such a gentle approach of training contributed to improved performance in world-class competitions, thus enabling them to reach consistently the highest step of the podium

A 3D Digital Approach to the Stylistic and Typo-Technological Study of Small Figurines from Ayia Irini, Cyprus

The thesis aims to develop a 3D digital approach to the stylistic and typo-technological study of coroplastic, focusing on small figurines. The case study to test the method is a sample of terracotta statuettes from an assemblage of approximately 2000 statues and figurines found at the beginning of the 20th century in a rural open-air sanctuary at Ayia Irini (Cyprus) by the archaeologists of the Swedish Cyprus Expedition. The excavators identified continuity of worship at the sanctuary from the Late Cypriot III (circa 1200 BC) to the end of the Cypro-Archaic II period (ca. 475 BC). They attributed the small figurines to the Cypro-Archaic I-II. Although the excavation was one of the first performed through the newly established stratigraphic method, the archaeologists studied the site and its material following a traditional, merely qualitative approach. Theanalysis of the published results identified a classification of the material with no-clear-cut criteria, and their overlap between types highlights ambiguities in creating groups and classes. Similarly, stratigraphic arguments and different opinions among archaeologists highlight the need for revising. Moreover, pastlegislation allowed the excavators to export half of the excavated antiquities, creating a dispersion of the assemblage. Today, the assemblage is still partly exhibited at the Cyprus Museum in Nicosia and in four different museums in Sweden. Such a setting prevents to study, analyse and interpret the assemblageholistically. This research proposes a 3D chaîne opératoire methodology to study the collection’s small terracotta figurines, aiming to understand the context’s function and social role as reflected by the classification obtained with the 3D digital approach. The integration proposed in this research of traditional archaeological studies, and computer-assisted investigation based on quantitative criteria, identified and defined with 3D measurements and analytical investigations, is adopted as a solution to the biases of a solely qualitative approach. The 3D geometric analysis of the figurines focuses on the objects’ shape and components, mode of manufacture, level of expertise, specialisation or skills of the craftsman and production techniques. The analysis leads to the creation of classes of artefacts which allow archaeologists to formulate hypotheses on the production process, identify a common production (e.g., same hand, same workshop) and establish a relative chronological sequence. 3D reconstruction of the excavation’s area contributes to the virtual re-unification of the assemblage for its holistic study, the relative chronological dating of the figurines and the interpretation of their social and ritual purposes. The results obtained from the selected sample prove the efficacy of the proposed 3D approach and support the expansion of the analysis to the whole assemblage, and possibly initiate quantitative and systematic studies on Cypriot coroplastic production

A wearable system that learns a kinematic model and finds structure in everyday manipulation by using absolute orientation sensors and a camera

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2005.Includes bibliographical references (p. 215-220).This thesis presents Duo, the first wearable system to autonomously learn a kinematic model of the wearer via body-mounted absolute orientation sensors and a head-mounted camera. With Duo, we demonstrate the significant benefits of endowing a wearable system with the ability to sense the kinematic configuration of the wearer's body. We also show that a kinematic model can be autonomously estimated offline from less than an hour of recorded video and orientation data from a wearer performing unconstrained, unscripted, household activities within a real, unaltered, home environment. We demonstrate that our system for autonomously estimating this kinematic model places very few constraints on the wearer's body, the placement of the sensors, and the appearance of the hand, which, for example, allows it to automatically discover a left-handed kinematic model for a left-handed wearer, and to automatically compensate for distinct camera mounts, and sensor configurations. Furthermore, we show that this learned kinematic model efficiently and robustly predicts the location of the dominant hand within video from the head-mounted camera even in situations where vision-based hand detectors would be likely to fail.(cont.) Additionally, we show ways in which the learned kinematic model can facilitate highly efficient processing of large databases of first person experience. Finally, we show that the kinematic model can efficiently direct visual processing so as to acquire a large number of high quality segments of the wearer's hand and the manipulated objects. Within the course of justifying these claims, we present methods for estimating global image motion, segmenting foreground motion, segmenting manipulation events, finding and representing significant hand postures, segmenting visual regions, and detecting visual points of interest with associated shape descriptors. We also describe our architecture and user-level application for machine augmented annotation and browsing of first person video and absolute orientations. Additionally, we present a real-time application in which the human and wearable cooperate through tightly integrated behaviors coordinated by the wearable's kinematic perception, and together acquire high-quality visual segments of manipulable objects that interest the wearable.by Charles Clark Kemp.Ph.D

Automated retinal analysis

Diabetes is a chronic disease affecting over 2% of the population in the UK [1]. Long-term complications of diabetes can affect many different systems of the body including the retina of the eye. In the retina, diabetes can lead to a disease called diabetic retinopathy, one of the leading causes of blindness in the working population of industrialised countries. The risk of visual loss from diabetic retinopathy can be reduced if treatment is given at the onset of sight-threatening retinopathy. To detect early indicators of the disease, the UK National Screening Committee have recommended that diabetic patients should receive annual screening by digital colour fundal photography [2]. Manually grading retinal images is a subjective and costly process requiring highly skilled staff. This thesis describes an automated diagnostic system based oil image processing and neural network techniques, which analyses digital fundus images so that early signs of sight threatening retinopathy can be identified. Within retinal analysis this research has concentrated on the development of four algorithms: optic nerve head segmentation, lesion segmentation, image quality assessment and vessel width measurements. This research amalgamated these four algorithms with two existing techniques to form an integrated diagnostic system. The diagnostic system when used as a 'pre-filtering' tool successfully reduced the number of images requiring human grading by 74.3%: this was achieved by identifying and excluding images without sight threatening maculopathy from manual screening

Hidden Markov Models for Visual Speech Synthesis in Limited Data

This work presents a new approach for estimating control points (facial locations that control movement) to allow the artificial generation of video with apparent mouth movement (visual speech) time-synced with recorded audio. First, Hidden Markov Models (HMMs) are estimated for each visual speech category (viseme) present in stored video data, where a category is defined as the mouth movement corresponding to a given sound and where the visemes are further categorized as trisemes (a viseme in the context of previous and following visemes). Next, a decision tree is used to cluster and relate states in the HMMs that are similar in a contextual and statistical sense. The tree is also used to estimate HMMs that generate sequences of visual speech control points for trisemes not occurring in the stored data. An experiment is described that evaluates the effect of several algorithm variables, and a statistical analysis is presented that establishes appropriate levels for each variable by minimizing the error between the desired and estimated control points. The analysis indicates that the error is lowest when the process is conducted with three-state left-to right no skip HMMs trained using short-duration dynamic features, a high log-likelihood threshold, and a low outlier threshold. Also, comparisons of mouth shapes generated from the artificial control points and the true control points (estimated from video not used to train the HMMs) indicate that the process provides accurate estimates for most trisemes tested in this work. The research presented here thus establishes a useful method for synthesizing realistic audio-synchronized video facial features

Using 3D sensing and projecting technology to improve the mobility of Parkinson's disease patients

This thesis was submitted for the award of Doctor of Philosophy and was awarded by Brunel University LondonParkinson’s is a neurological condition in which parts of the brain responsible for movements becomes incapacitated over time due to the abnormal dopamine equilibrium. Freezing of Gait (FOG) is one of the main Parkinson’s Disease (PD) symptoms that affects patients not only physically but also psychologically as it prevents them from fulfilling simple tasks such as standing up or walking. Different auditory and visual cues have been proven to be very effective in improving the mobility of People with Parkinson’s (PwP). Nonetheless, many of the available methods require user intervention or devices to be worn, charged, etc. to activate the cues. This research suggests a system that can provide an unobtrusive facility to detect FOG and falling in PwP as well as monitoring and improving their mobility using laser-based visual cues casted by an automated laser system. It proposes a new indoor method for casting a set of two parallel laser lines as a dynamic visual cue in front of a subject’s feet based on the subject’s head direction and 3D location in a room. The proposed system controls the movement of a set of pan/tilt servo motors and laser pointers using a microcontroller based on the real-time skeletal information acquired from a Kinect v2 sensor. A Graphical User Interface (GUI) is created that enables users to control and adjust the settings based on the user preferences. The system was tested and trained by 12 healthy participants and reviewed by 15 PwP who suffer from frequent FOG episodes. The results showed the possibility of employing the system as an indoor and on-demand visual cue system for PwP that does not rely on the subject’s input or introduce any additional complexities to operate. Despite limitations regarding its outdoor use, feedback was very positive in terms of domestic usability and convenience, where 12/15 PwP showed interest in installing and using the system at their homes

3D face modelling from sparse data

EThOS - Electronic Theses Online ServiceGBUnited Kingdo

The use of linear and nonlinear methods for evaluating balance on collegiate men???s and women???s ice hockey teams throughout a season

If objective data from balance assessments are to be used in assessing player???s for returning to play, it is necessary to understand the in-season variability that can occur. The purpose of this work was to determine if the time evolving nature of these measures can reveal insights, that more effective return-to-lay guidelines can be stablished. Forty-six varsity ice hockey players participated during the 2014-15 season. All underwent baseline measurements and were tested ever 4 weeks throughout the season, plus one post-season session. Dependent linear (mean power frequency, mean velocity, and total excursion) and nonlinear (approximate entropy) measures were used to interpret force plate data. Linear and nonlinear measures both showed significant main effects of time. Monthly testing throughout the season demonstrated decreases in mean values for all measures with respect to baseline. In-season variability of balance postures recorded can be used when comparing concussed athlete???s baseline measures to post-concussion measures

Dynamic impact testing and computer simulation of wheelchair tiedown and occupant restraint systems (WTORS).

Occupant Restraint Systems (ORS) have been widely used in Public Service Vehicles (PSVs). A Wheelchair Tiedown and Occupant Restraint System (WTORS) has been developed to provide effective occupant protection for disabled people who are seated in wheelchairs. An international laboratory study had been conducted to produce a compliance test protocol that included specification of the sled deceleration versus time history and the crash pulse corridor. Currently effort at the international level is being focused through the International Standards Organisation (ISO) to produce standards for WTORS and transportable wheelchairs. Dynamic sled testing of WTORS was conducted in Middlesex University Road Safety Engineering Laboratory (MURSEL) to develop a test protocol in a WTORS System. This research has been concerned with the effects to which the occupant of a wheelchair secured by a WTORS is subjected in a frontal impact. Both occupant Forward Facing Frontal (FFF) and Rearward Facing Frontal (RFF) impact configurations have been considered. A Surrogate wheelchair with a tiedown restraint System, a Surrogate occupant restraint System, and an Anthropomorphic Test Dummy (ATD) were used to facilitate highly controlled tests. Production wheelchairs were also crash tested to validate the response of the Surrogate System. A 48 km/h-20g crash pulse falling within the ISO standard crash pulse corridor was specified. The Crash Victim Simulation (CVS), one of the computer modelling methods, and Finite Element Analysis (FEA) models were designed to study the dynamic response of a restrained wheelchair and its occupant in a crash environment. Two CVS computer packages: MADYMO®, DYNAMAN® and one of FEA programs: PAFEC were used in WTORS models to predict the occupant response during impacts and hence provide data to optimise future system design. A modelling protocol for WTORS was developed based on the results of ninety (90) sled tests of WTORS Surrogate system and forty (40) dynamic tests of production wheelchairs. To illustrate the potential of these models the results of simulations were validated by sled tests. A random effects Statistical method was used to quantify the results. The load-time histories were also traced to qualify the test and model results. A literature review highlighted twenty years of wheelchair crash research. The correlation between computer model and experimental results was made more accurately. The modelling technique of interconnection of FEA models into CVS program was also introduced. The velocity profile and the natural frequency of WTORS analysis were used to explain why the wheelchair and dummy experienced acceleration amplifications relative to the sled. The shoulder belt load at floor-mounted configuration was found to be higher than that at B pillar configuration. Energy principles were also applied to show why more compliant wheelchair tiedown Systems subjected restraints to a less severe crash environment. A decomposition of forces using the computer model showed why quasi-static analysis is insufficient in WTORS design. It is concluded that the B pillar anchorage of the occupant diagonal strap is superior to the floor-mounted configuration