O trabalho teve como objetivo analisar a associação entre a deambulação e a duração da fase ativa do trabalho de parto e avaliar o nível de dor da parturiente durante toda esta fase. 0bjetivos específicos: 1)identificar quantitativamente o trajeto percorrido durante a deambulação de parturientes no trabalho de parto; 2) verificar a presença de correlação entre a distância deambulada e a duração da fase ativa do trabalho de parto; 3) verificar a presença de correlação entre a distância deambulada a cada hora do trabalho de parto com a duração do mesmo; 4) avaliar o nível de dor da parturiente durante toda a fase ativa do trabalho de parto. Metodologia: estudo analítico de intervenção do tipo quase experimental. Fizeram parte do estudo 80 parturiente primíparas, admitidas em trabalho de parto espontâneo, no início da fase ativa (4 a 5 cm de dilatação cervical), que foram monitoradas em toda a fase ativa do trabalho de parto, ou seja, até completar 10 cm de dilatação cervical e encaminhamento para a sala de parto. Instrumentos de coleta de dados: podômetro para medir a distância percorrida em metros, Escala Visual Numérica de dor (EVN), formulário para o registro de dados. Análise dos dados: distribuição de freqüência, teste de Correlação paramétrico de Pearson, teste de Correlação não paramétrico de Spearman e teste de Regressão Linear Simples. Resultados: as participantes percorreram uma distância média de 1624metros, 63,09% da fase ativa do trabalho de parto e em um tempo médio de 5 horas. Verificou-se que a quantidade deambulada durante as três primeiras horas da fase ativa está associada a um encurtamento do trabalho de parto, sendo que a cada 100 metros percorridos ocorreu uma diminuição de 22 minutos na primeira hora, 10 minutos na segunda hora e 6 minutos na terceira hora. Os dados apontam que a indicação do uso de ocitócito e ruptura da bolsa amniótica não influenciaram na duração da fase ativa do trabalho de parto. Quanto aos escores de dor, verificou-se que a pontuação dos mesmos aumentou à medida que a dilatação cervical avançava. Foi encontrada uma correlação positiva apenas aos 5 cm de dilatação, ou seja, quanto maior os trajetos percorridos maiores foram os escores de dor pontuados pelas parturientes. / This study aimed to analyze the association between walking and the duration of the active phase of labor and obstetric results, with the following specific objectives: 1) identify the distance women walked during labor; 2) verify whether the distance walked is correlated with the duration of the active phase of labor; 3) verify whether the distance walked during each hour of labor is correlated with its duration; 4) evaluate the parturient women’s pain level throughout the active phase of labor. Methodology: We realized an analytic, quasi-experimental intervention study. Study participants were 80 primiparous parturient women, who were admitted during spontaneous labor, at the start of the active phase (4 to 5cm of cervical dilatation) and were monitored throughout the entire active phase of labor, that is, until they reached 10cm of cervical dilatation and were sent to the delivery room. Data collection instruments: podometer to measure the distance walked in meters, numerical visual pain scale, and form for data registration. Data analysis: frequency distribution, Pearson’s parametric correlation test, Spearman’s non-parametric correlation test and Simple Linear Regression test. Results: the parturient women walked an average distance of 1624 meters, 63.09% of the active phase of labor and during an average time of 5 hours. We observed that the distance walked during the first three hours of the active phase is associated with a shorter labor time. For every 100 meters walked, duration decreased by 22 minutes during the first hour, by 10 minutes during the second hour and by 6 minutes during the third hour. Data revealed that the indication of oxytocic agents and the rupture of the amniotic bag did not influence the duration of the active phase of labor. Pain scores increase along with the advance in cervical dilatation. However, we only found a significant positive correlation when 5cm of dilatation had been reached, that is, the more distance the participants walked, the higher the pain scores they reached.

Many environments are inaccessible or hazardous for humans. Remaining debris after earthquake and fire, ship hulls, bridge installations, and oil rigs are some examples. For these environments, major effort is being placed into replacing humans with robots for manipulation purposes such as search and rescue, inspection, repair, and maintenance. Mobility, manipulability, and stability are the basic needs for a robot to traverse, maneuver, and manipulate in such irregular and highly obstructed terrain. Hexapod walking robots are as a salient solution because of their extra degrees of mobility, compared to mobile wheeled robots. However, it is essential for any multi-legged walking robot to maintain its stability over the terrain or under external stimuli. For manipulation purposes, the robot must also have a sufficient workspace to satisfy the required manipulability. Therefore, analysis of both workspace and stability becomes very important. An accurate and concise inverse kinematic solution for multi-legged robots is developed and validated. The closed-form solution of lateral and spatial reachable workspace of axially symmetric hexapod walking robots are derived and validated through simulation which aid in the design and optimization of the robot parameters and workspace. To control the stability of the robot, a novel stability margin based on the normal contact forces of the robot is developed and then modified to account for the geometrical and physical attributes of the robot. The margin and its modified version are validated by comparison with a widely known stability criterion through simulated and physical experiments. A control scheme is developed to integrate the workspace and stability of multi-legged walking robots resulting in a bio-inspired reactive control strategy which is validated experimentally.

Walking is an essential behavior across the animal kingdom. To navigate complex environments, animals must have highly robust, yet flexible locomotor behaviors. One crucial aspect of this process is the selection of an appropriate walking speed. Speed shifts entail not only the scaling of behavioral parameters (such as faster steps) but also changes in coordination to produce different gaits, and the details of how this switch occurs are currently unknown. Modulatory substances, particularly small biogenic amine neurotransmitters, can alter the output and even the connectivity of motor circuits. This work addresses the hypothesis that one such neuromodulator – serotonin (5HT) – is a key regulator of walking speed at the level of motor circuitry. To explore this question, I use the model organism Drosophila melanogaster which, like vertebrates, displays complex coordinated locomotion at a wide range of speeds. In Chapter 2, I will describe our efforts to characterize the anatomy of the serotonergic cell populations that provide direct input to motor circuitry. I find that innervation of the neuropil of the ventral nerve cord - a structure roughly analagous to the mammalian spinal cord - is provided primarily by local modulatory interneurons. Using stochastic single cell labeling techniques, I will detail the specific anatomy of individual neuromodulatory cells, and also the distribution of synapses across their processes. In Chapter 3, I will show that optogenetic activation or tonic inhibition of VNC serotonergic neurons produces opposing shifts in walking speed. To analyze behavior, I will use two complementary approaches. On the one hand, I will use an arena assay to holistically assess walking velocity and frequency. On the other, I will use a behavioral assay developed in the lab - the Flywalker - to assess walking kinematics at high resolution. The combination of these technique will give us a broad and specific picture of how the VNC serotonergic system modulates walking. In Chapter 4, I will identify natural behavioral contexts under which serotonin is used to shift walking behavior. I will use a variety of paradigms that induce animals to shift their speed, from changes in orientation and nutrition state, to pulses of light, odor, and a vibration. I will assess the requirement for the VNC serotonergic system under all of these conditions, to build a clearer picture of its role in modulating behavioral adaptation. In Chapter 5, I will describe our efforts, in collaboration with Pavan Ramdya's lab at EPFL, to functionally image VNC serotonergic cells while the animal is walking, to understand how activity is endogenously regulated in this population. Finally, in Chapter 6 I will characterize the circuit elements which might be responsible for serotonin's effect on walking. I will use recently developed mutant lines to identify the particular serotonergic receptors responsible for enacting shifts in walking behavior. Using genetic labeling tools, I will identify potential targets of serotonergic signaling in the VNC, and formulate a model by which action on these targets could adjust locomotor output. Altogether, this work seeks to characterize the anatomy and behavioral role of the VNC serotonergic system in Drosophila. I hope that through this work, I will gain a deeper understanding of not only this particular modulatory system in this particular behavioral context, but also of how static circuits are conferred with essential flexibility in behaving animals.

With increasing rates of obesity, research has begun to focus of co-morbidities of obesity such as osteoarthritis. The majority of existing research has focused on older adults as the group most likely to suffer from osteoarthritis. The purpose of this study was to determine if overweight and obese young adults exhibit biomechanical risk factors for knee osteoarthritis, and to determine if young adults with biomechanical risk factors of osteoarthritis can modify these with instruction. This purpose was divided into two separate studies. Study 1: Thirty adults between 18-35 years old were recruited into three groups according to body mass index: normal, overweight, and obese. Participants walked through the lab while we collected 3-d kinematic and kinetic data. Overweight and obese young adults walked with similar gait compared to normal weight young adults. Study 2: Nine young adults between 18-35 years were recruited who walked with stiff-knee gait. Baseline measures of gait were collected in the form of 3-d kinematics and kinetics as participants walked through the laboratory. They then completed the gait instruction program which consisted of four blocks of training. Each block included ten single steps where the participant was provided feedback, followed by 100 practice steps around the laboratory. Participants were successful in increasing sagittal plane kinematics and kinetics of interest in the study. Conclusion: Identifying individuals who had biomechanical risk factors of osteoarthritis according to body mass index was not possible. According to the results of our study, obese and overweight young adults are not at increased risk of osteoarthritis compared to normal weight young adults. Individuals who may be at increased risk due to stiff-knee gait were able to improve their gait following instruction.

The effects of multiple sclerosis (MS) on the central nervous system often manifest as abnormalities in gait kinematics. Clinically practical, valid, and reliable measures of gait kinematics are necessary to address research and clinical questions about MS. Wireless flexible electrogoniometry (EG) is a clinically practical measure of joint angles. The GAITRite walkway system is a clinically practical, valid and reliable measure of temporal and spatial gait characteristics. The overall objective of this two-study research project was to explore whether these clinically practical measures of gait kinematics can be used to accurately detect gait abnormalities in people with multiple sclerosis. Study 1 examined the reliability and validity of EG and Study 2 examined the gait kinematics of people with MS (PWMS) using EG and GAITRite. For Study 1, angle at initial contact and total joint excursion were measured by EG at both the knee and ankle while ten healthy adults walked at a self-selected comfortable speed. Measurements were repeated for two testers and two visits to assess reliability. The same variables were measured concurrently with three-dimensional motion analysis (3D) to assess validity. For all variables, reliability was good as indicated by low measurement error and validity was good as indicated by association and agreement of EG with 3D. For Study 2, the same joint angles, along with speed, cadence, step length, stride length, stance duration and double support duration were assessed for six PWMS and six controls without MS. PWMS showed significantly reduced speed, cadence, and ankle excursion and increased stance and double support duration as previously shown with 3D. Spasticity and/or instability may lead to these kinematic gait abnormalities in PWMS; however, reduced velocity may confound this interpretation by affecting the other observed gait abnormalities. Further research about the determinants of gait dysfunction in PWMS is required. EG and GAITRite are clinically practical, valid and reliable measures of gait kinematics and should be included in further clinic-based research to determine which kinematic gait abnormalities are causes and which are effects of the observed decrease in gait speed in PWMS.

Impact at each leg transition is one of the main causes of energy dissipation in most of the current bipedal walking robots. Minimizing impact can reduce the energy loss. Instead of controlling the joint angle profiles to reduce the impact which requires significant amount of energy, installing elastic mechanisms on the robots structure is proposed in this research, enabling the robot to reduce the impact, and to store part of the energy in the elastic form which returns the energy to the robot. Practically, this motivates the development of the bipedal walking robots with adjustable stiffness elasticity which itself creates new challenging problems. This thesis addresses some of the challenges through five consecutive stages. Firstly, an adjustable compliant series elastic actuator (named ACSEA in this thesis) is developed. The velocity control mode of the electric motor is used to accurately control the output force of the ACSEA. Secondly, three different conceptual designs of the adjustable stiffness artificial tendons (ASAT) are proposed each of which is added at the ankle joint of a bipedal walking robot model. Simulation results of the collision phase (part of the gait between the heel-strike and the foot-touch-down in bipedal walking) demonstrate significant improvements in the energetics of the bipedal walking robot by proper stiffness adjustment of ASAT. In the third stage, in order to study the effects of ASATs on reducing the energy loss during the stance phase, a simplified model of bipedal walking is introduced consisting of a foot, a leg and an ASAT which is installed parallel to the ankle joint. A linear spring, with adjustable stiffness, is included in the model to simulate the generated force by the trailing leg during the double support phase. The concept of impulsive constraints is used to establish the mathematical model of impacts in the collision phase which includes the heel-strike and the foot-touch-down. For the fourth stage, an energy-feedback-based controller is designed to automatically adjust the stiffness of the ASAT which reduces the energy loss during the foot-touch-down. In the final stage, a speed tracking (ST) controller is developed to regulate the velocity of the biped at the midstance. The ST controller is an event-based time-independent controller, based on geometric progression with exponential decay in the kinetic energy error, which adjusts the stiffness of the trailing-leg spring to control the injected energy to the biped in tracking a desired speed at the midstance. Another controller is also integrated with the ST controller to tune the stiffness of the ASAT when reduction in the speed is desired. Then, the local stability of the system (biped and the combination of the above three controllers) is analyzed by calculating the eigenvalues of the linear approximation of the return map. Simulation results show that the combination of the three controllers is successful in tracking a desired speed of the bipedal walking even in the presence of the uncertainties in the leg’s initial angles. The outcomes of this research show the significant effects of adjustable stiffness artificial tendons on reducing the energy loss during bipedal walking. It also demonstrates the advantages of adding elastic elements in the bipedal walking model which benefits the efficiency and simplicity in regulating the speed. This research paves the way toward developing the dynamic walking robots with adjustable stiffness ability which minimize the shortcomings of the two major types of bipedal walking robots, i.e., passive dynamic walking robots (which are energy efficient but need extensive parameters tuning for gait stability) and actively controlled walking robots (which are significantly energy inefficient). / May 2008

Rapporten behandlar utvecklingsarbetet av ett nytt gåbord i samarbete med Skaraborgs sjukhus. Målet med arbetet var delvis att lokalisera och lösa de problem som fanns med det befintliga gåbordet. Samt utöver detta utveckla och göra bordet ergonomiskt anpassat för både vårdare och patient. Arbetet är uppdelat i bakgrund, förstudie, idégenerering, konceptutveckling och till sist ett resultat. I förstudien har de olika gåbord som finns på marknaden studerats och vilka problem det finns med dessa genom intervjuer med berörda parter. Genom en innehållsrik kravspecifikation och riktlinjer från Svensk standard (ISO-11199, 2005) har arbetet haft tydliga ramar för den utvecklande processen. Med hjälp av ett antal kreativitetsmetoder har ett stort antal lösningar hittats som efter en utvärdering gallrats till ett fåtal kvarvarande. Efter det följande utvecklingsarbetet har dessa idéer förbättrats till ett slutgiltigt koncept, en produkt som möter de krav som satts upp. / This report deals with the development of a new walking table in cooperation with the hospitals in Skaraborg. The goal was partally to locate and solve the problems that existed with the walking aid, and with a usability outlook develop the table to suit both nurses and patients. The work is divided into a literature study, idea generation, concept development and finally a result part. In the preliminary study, the group looked at various walking tables available on the market today and what problems there are with them through interviews. Through a comprehensive specification of requirements and guidelines from the Swedish standard association, the work could go on to the developing process. With the help of some different creativity techniques, a large number of solutions where found, and after evaluating these solutions a smaller amount of concepts could be developed futher. After improvement of these ideas, the project resulted in a product that met the requirements set by the user and project team.

One of the most poorly understood co-morbidities associated with obesity is the pathway to osteoarthritis of the knee. To implement appropriate preventative strategies, it is important to explore how obesity is a causal factor for osteoarthritis. The present research compared the kinematics and kinetics of a group of young obese, but otherwise healthy, adults to a group of young, healthy-weight adults, in an attempt to identify mechanical abnormalities at the knee during walking that may predispose the obese to osteoarthritis of the knee. Optotrak motion capture (Northern Digital Inc. Waterloo, Ontario) and a forceplate (AMTI OR6-7, Advanced Mechanical Technology Inc, Watertown, MA) were used to measure ground reaction forces and moments of 16 participants – 8 obese and 8 sex-, age- and height-matched healthy-weight – to analyze knee joint kinematics and kinetics at three walking speeds. Participants wore an accelerometer (ActiGraph GT3X, Fort Walton Beach, USA) for seven days to measure daily steps counts. Dependent t-tests were performed to determine group differences in ground reaction forces, knee angles and knee moments, as well as knee adduction moment impulse and cumulative knee adductor load (CKAL). The obese group walked at a significantly slower self-selected speed (p=0.013). While not statistically significant, the obese group did present with a more valgus mean dynamic knee alignment than the health-weight group. A significantly greater maximum abduction angle (p=0.009) and smaller minimum knee flexion angle at heel contact (p=0.001) was found in the obese group. A significant difference was found in the peak medial rotation moment in the transverse plane (p=0.003). A greater stance duration lead to a significantly greater knee adduction moment impulse (p=0.049) in the obese group. While significant group differences were not found in the steps per day, the obese group had a significantly greater CKAL (p=0.025). Obese young adults with healthy knees demonstrated a gait pattern of reduced medial knee joint compartment loading through greater knee abduction, medial knee rotation and a slower walking speed compared to matched controls. The ramifications of gait modifications on long-term musculoskeletal health remain unknown, but compensations may lead to increased risk of osteoarthritis of the knee.

The effects of multiple sclerosis (MS) on the central nervous system often manifest as abnormalities in gait kinematics. Clinically practical, valid, and reliable measures of gait kinematics are necessary to address research and clinical questions about MS. Wireless flexible electrogoniometry (EG) is a clinically practical measure of joint angles. The GAITRite walkway system is a clinically practical, valid and reliable measure of temporal and spatial gait characteristics. The overall objective of this two-study research project was to explore whether these clinically practical measures of gait kinematics can be used to accurately detect gait abnormalities in people with multiple sclerosis. Study 1 examined the reliability and validity of EG and Study 2 examined the gait kinematics of people with MS (PWMS) using EG and GAITRite. For Study 1, angle at initial contact and total joint excursion were measured by EG at both the knee and ankle while ten healthy adults walked at a self-selected comfortable speed. Measurements were repeated for two testers and two visits to assess reliability. The same variables were measured concurrently with three-dimensional motion analysis (3D) to assess validity. For all variables, reliability was good as indicated by low measurement error and validity was good as indicated by association and agreement of EG with 3D. For Study 2, the same joint angles, along with speed, cadence, step length, stride length, stance duration and double support duration were assessed for six PWMS and six controls without MS. PWMS showed significantly reduced speed, cadence, and ankle excursion and increased stance and double support duration as previously shown with 3D. Spasticity and/or instability may lead to these kinematic gait abnormalities in PWMS; however, reduced velocity may confound this interpretation by affecting the other observed gait abnormalities. Further research about the determinants of gait dysfunction in PWMS is required. EG and GAITRite are clinically practical, valid and reliable measures of gait kinematics and should be included in further clinic-based research to determine which kinematic gait abnormalities are causes and which are effects of the observed decrease in gait speed in PWMS.

Walking can be a safe, healthy, and affordable mode of school transportation. However, most students today do not use walking for their school travel. More research is needed to understand the correlates of walking to or from school and to identify effective interventions. This is a cross-sectional study of 73 public elementary schools in the Austin Independent School District of Texas. The first phase used geographic information systems and field audits to examine school-level disparities in the environmental support for walking in schools’ attendance areas. The second phase involved surveys of students’ parents or guardians to identify the multi-level correlates of using walking as their children’s typical school travel mode. In the first phase, results from analyses of variance and linear regressions indicated the existence of disparities. Lower economic status of student population was associated with poorer street conditions (e.g., maintenance, visual quality, amenities, and perceived safety), shorter distances to school, and lower traffic volumes. Higher percentage of Hispanic students within a school was associated with increased danger from traffic and crime and more sidewalks, greater population density, and mixed land uses. The second phase used binary logistic regressions to predict walking to or from school. Among the personal and social factors, parents’ education, car ownership, personal barriers, and school bus availability were negative correlates, while parents’ and children’s positive attitude and regular walking habit and supportive peer influences were positive correlates. Of the physical environmental factors, long distance and safety concerns were the strongest negative correlates, followed by the presence of highways or freeways, convenience stores, office buildings, and bus stops en route. In conclusion, environmental interventions are needed to develop centrallylocated neighborhood schools, barrier-free attendance areas, and well-maintained pedestrian infrastructure. Disparities and fine-grained differences are found in the environmental support for walking. A high priority for low-income, Hispanic children and interventions tailored for specific contexts and populations appear necessary. Safety improvement is indispensible in terms of both traffic and crime and should be supplemented with educational programs that target both parents and children. Finally, multi-agency collaborations are needed at the policy level to support and facilitate these multi-level interventions.