Improving activity recognition using a wearable barometric pressure sensor in mobility-impaired stroke patients.

© 2015 Massé et al.Background: Stroke survivors often suffer from mobility deficits. Current clinical evaluation methods, including questionnaires and motor function tests, cannot provide an objective measure of the patients mobility in daily life. Physical activity performance in daily-life can be assessed using unobtrusive monitoring, for example with a single sensor module fixed on the trunk. Existing approaches based on inertial sensors have limited performance, particularly in detecting transitions between different activities and postures, due to the inherent inter-patient variability of kinematic patterns. To overcome these limitations, one possibility is to use additional information from a barometric pressure (BP) sensor. Methods: Our study aims at integrating BP and inertial sensor data into an activity classifier in order to improve the activity (sitting, standing, walking, lying) recognition and the corresponding body elevation (during climbing stairs or when taking an elevator). Taking into account the trunk elevation changes during postural transitions (sit-to-stand, stand-to-sit), we devised an event-driven activity classifier based on fuzzy-logic. Data were acquired from 12 stroke patients with impaired mobility, using a trunk-worn inertial and BP sensor. Events, including walking and lying periods and potential postural transitions, were first extracted. These events were then fed into a double-stage hierarchical Fuzzy Inference System (H-FIS). The first stage processed the events to infer activities and the second stage improved activity recognition by applying behavioral constraints. Finally, the body elevation was estimated using a pattern-enhancing algorithm applied on BP. The patients were videotaped for reference. The performance of the algorithm was estimated using the Correct Classification Rate (CCR) and F-score. The BP-based classification approach was benchmarked against a previously-published fuzzy-logic classifier (FIS-IMU) and a conventional epoch-based classifier (EPOCH). Results: The algorithm performance for posture/activity detection, in terms of CCR was 90.4 %, with 3.3 % and 5.6 % improvements against FIS-IMU and EPOCH, respectively. The proposed classifier essentially benefits from a better recognition of standing activity (70.3 % versus 61.5 % [FIS-IMU] and 42.5 % [EPOCH]) with 98.2 % CCR for body elevation estimation. Conclusion: The monitoring and recognition of daily activities in mobility-impaired stoke patients can be significantly improved using a trunk-fixed sensor that integrates BP, inertial sensors, and an event-based activity classifier

Specialized physiological studies in support of manned space flight

The effects of a diuretic (Lasix) induced dehydration on the cardiovascular and hematological responses to lower body negative pressure (LBNP) were analyzed and compared to previous observations on dehydration following exercise in the heat. During LBNP runs the subjects were monitored for changes in blood volume, heart rate, blood pressure, and variations in the volume of the left calf. It was concluded that Lasix dehydration produced a depletion of the body electrolytes at the expense of both the plasma and extravascular compartments. Striking differences were found between those subjects who were physically active (Runners: R) and those who did not engage in any regular physical activity (Non-runners: NR). Tolerance to LBNP (Torr x min) was significantly lower in the R's than the NR's before and after dehydration, however the R's lost more of their tolerance after dehydration with Lasix than after exercise in the heat for about the same fluid loss. The opposite was true for the NR's. Two factors appear to be responsible for the lower LBNP tolerance in R's: parasympathetic inhibition of cardiac activity during LBNP and a greater propensity to pool blood in the lower extremities

Reaching for the Future - Building a professional trajectory

Science teachers need to consider how they want to grow professionally. Thinking about one’s future involves identifying the knowledge, practices, and attributes needed in a new role. By using a framework such as the science education trajectory (SET), teachers can more easily consider their professional options and work strategically toward them. The report on science teacher learning (NASEM 2015) emphasizes that teachers need strategic and coherent learning opportunities. Until there are defined pathways toward different positions, science teachers will need to organize their learning opportunities in such a way that they can learn intentionally and progressively. This is important to consider, as teachers do not typically have a prepared program of professional development opportunities tailored to their personal needs or professional goals (NASEM 2015). Most professional development programs available to science teachers focus on improving instructional practice (Luft and Hewson 2014). This seems appropriate with the emergence of the Next Generation Science Standards (NGSS) (NGSS Lead States 2013), but these types of programs comprise only one area in the universe of potential professional opportunities. Our goal is to help science teachers consider their professional options. We suggest a process to build a professional growth or learning plan, which we call a SET. A SET is specific to science education, and describes the knowledge, practices, and attributes a teacher needs to develop in order to progress to a new professional role (Luft et al. forthcoming). While this is not a classroom-based article, we hope to show teachers how they can grow professionally and benefit their students, their learning environment, and the science teaching profession

Cortical Plasticity during Motor Learning and Recovery after Ischemic Stroke

The motor system has the ability to adapt to environmental constraints and injury to itself. This adaptation is often referred to as a form of plasticity allowing for livelong acquisition of new movements and for recovery after stroke. We are not sure whether learning and recovery work via same or similar neural mechanisms. But, all these processes require widespread changes within the matrix of the brain. Here, basic mechanisms of these adaptations on the level of cortical circuitry and networks are reviewed. We focus on the motor cortices because their role in learning and recovery has been investigated more thoroughly than other brain regions

Coherent states on the circle

We present a possible construction of coherent states on the unit circle as configuration space. In our approach the phase space is the product Z x S^1. Because of the duality of canonical coordinates and momenta, i.e. the angular variable and the integers, this formulation can also be interpreted as coherent states over an infinite periodic chain. For the construction we use the analogy with our quantization over a finite periodic chain where the phase space was Z_M x Z_M. Properties of the coherent states constructed in this way are studied and the coherent states are shown to satisfy the resolution of unity.Comment: 7 pages, presented at GROUP28 - "28th International Colloquium on Group Theoretical Methods in Physics", Newcastle upon Tyne, July 2010. Accepted in Journal of Physics Conference Serie

Primer registro de hospedador para el parasitoide oófilo, Polynema haitianum (Hymenoptera: Mymaridae), con descripción del macho y redescripción de la hembra

El presente trabajo científico provee la primera asociación hospedador - parasitoide y amplía la distribución geográfica para el parasitoide Polynema haitianum Dozier (Hymenoptera: Mymaridae) a varios paises de Sudamérica, previamente conocido para Haití. Además se describió el macho y se redescribio la hembra. En este trabajo se obtuvo una especie de parasitoides de huevos, Polynema haitianum, la cual se desarrolla en huevos de Xerophloea viridis (Hemiptera: Cicadellidae). Con el registro de P. haitianum se eleva a tres el número de las especies de parasitoides que atacan a la chicharrita X. viridis, en Argentina.Fil: Luft Albarracin, Erica Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Planta Piloto de Procesos Industriales Microbiologicos; ArgentinaFil: Aquino, Daniel A.. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Entomología; Argentin

Role of walking-exercise therapy after stroke

Stroke commonly leads to reduced mobility, which leads to deconditioning and a worsening of vascular risk factors, such as diabetes. The worsened risk profile leads to further strokes and disability--a vicious cycle for the stroke survivor. Exercise (walking) therapy may break this cycle by providing adequate stimuli for improving gait through plastic adaptation in the brain and through increasing fitness. Randomized, controlled data demonstrate the efficacy for gains in fitness and walking speed, the latter being related to lasting changes in activation patterns of the brainstem and cerebellum. Diabetes and muscle inflammation can also be improved by aerobic exercise training. The scope of this review summarizes these data and identifies unresolved issues related to optimization, intensity and maintenance of therapy effects. Exercise should be an integral part of every rehabilitation program

A Professional Development Program for Science Adjunct Faculty: The Mentoring-Learning Community (MLC)

Institutions of higher education have become increasingly dependent on adjunct faculty. These faculty members are often unfamiliar with current teaching strategies emphasizing an active learning approach. To support science adjunct faculty in learning about active learning, a professional development program was designed and implemented by the authors of this study, the Mentoring-Learning Community. The Mentoring-Learning Community program design was informed by literature regarding the use of professional development programs that focused on adjunct faculty. To determine the impact of this program, participants in the Mentoring-Learning Community were observed and interviewed over one semester. Mentoring-Learning Community participants transformed through all three Transformative Learning Theory dimensions, felt more empowered to utilize active learning approaches in their classrooms, and modified some aspects of their instruction

Examination of an Anecdotal “October Disappearance” of Northern Bobwhite in the Rolling Plains of Texas Through Demographic Data

Landowners and wildlife managers in the Rolling Plains ecological region of Texas, USA often report encountering northern bobwhite (Colinus virginianus; hereafter, bobwhite) in summer but observe what they perceive as a decrease in quail by early to mid-fall. As most bobwhite research in the Rolling Plains is focused on either breeding season or overwinter survival and movement, researchers rarely record demographic data during this late summer and early fall period. We examined weekly survival probabilities of bobwhite (n = 244) across 7 sites in the western Rolling Plains Ecoregion from August to late November in 2016, 2017, 2019, and 2020. Bobwhites were captured and equipped with very high frequency (VHF) transmitters and tracked 1–5 times/week. We used Akaike’s Information Criterion adjusted for small sample sizes (AICc) to evaluate a suite of candidate models comparing survival among and between years and survival between individual weeks to determine whether an unreported population decrease occurred during the study years. Our comparison of weekly survival probabilities considered survival to be different if 95% confidence intervals did not overlap. Our best supported model held survival constant among years and allowed survival to vary week by week. All other models received little support (ΔAICc \u3e 14.0). Examination of weekly survival probabilities failed to support a demographically driven hypothesis for decreased bobwhite observations from August to November. Though there was an observed decrease of weekly survival in the fourth week of September, it was not different than 16 of the 17 other weeks. We conclude that, for the years we measured, there was no support for a mass die-off hypothesis. Factors outside survival (e.g., a change in bobwhite behavior) may be driving the difference in detectability between late summer and late fall in the Rolling Plains of Texas