Different Phases Of Movement Research Articles

МОДЕЛЮВАННЯ РУХУ АВТОБУСА НА МАРШРУТІ МЕТРОБУСА

The paper proposes to model bus movement on metrobus route using driving cycles. Object of the study – bus traction-speed properties and fuel efficiency. Purpose of the study – model bus movement on metrobus route using driving cycles. Method of the study – analytical, mathematical modeling. Mathematical modeling can be used to assess metrobus system effectiveness, selection and justification of its rolling stock. It allows at the design stage determine performance properties of individual bus or metrobus system as a whole. Bus movement on metrobus route was proposed to model by using driving cycle, which reflects real operating conditions. It consists of successive sections, which include acceleration, movement with constant speed, braking and engine idle. Metrobus route Miloslavska St. – Pochayna metro station was chosen. It has 13 stops and 12 section. Each section of the route is simulated using a section of driving cycle one of two types and includes five different phases of movement. Driving cycle and mathematical model built on its basis allows to determine parameters of bus traction-speed properties and fuel efficiency (travel time, average speed and fuel consumption). KEYWORDS: METROBUS, BUS RAPID TRANSIT, DRIVING CYCLE, MATHEMATICAL MODEL, TRACTION-SPEED PROPERTIES, FUEL EFFICIENCY

Changes in Movement Coordination Associated With Skill Acquisition in Baseball Batting: Freezing/Freeing Degrees of Freedom and Functional Variability.

How do baseball batters solve the problem of coordinating the timing of the different phases of movement to generate a powerful swing that is appropriately adjusted for the trajectory of the pitch? How does the development of this coordination solution depend on the structure of practice? Previously unpublished ground reaction force (GRF) data were analyzed to investigate the swing coordination changes that were associated with the changes in batting performance found in the training study by Gray (2017). From pre–post training, there were significant increases in the magnitude of correlations between adjacent swing phases, significant increases in good variability (changes that keep the swing within the required temporal constraint), significant decreases in bad variability (changes that move the swing outside the temporal constraint), and stronger evidence of online adjustments of the different swing phases. These effects were significantly larger for the virtual environment (VE) Adaptive group from the Gray (2017) study that had higher variability in practice conditions. Across all participants, there were significant correlations between the changes in good and bad variability from pre–post training and measures of batting from VE and real hitting tests, and statistics from league play. These findings suggest that baseball batters solve the problem of coordination by developing functional variability and coupling between swing phases (Katsumata, 2007), which can be facilitated by having more variability in practice conditions.

Unpredictability in pedestrian flow: The impact of stochasticity and anxiety in the event of an emergency

Random interactions among pedestrians, usually produced by psychological effects (e.g. anxiety), can produce collective nontrivial phenomena in their flow dynamics. Here, we improve our understanding on these phenomena by implementing cellular automaton (CA) simulations in a simplified one-dimensional corridor model. We consider different types of randomness that could be used to parametrize social, cultural or psychological behaviors; their incidence on the average evacuation time and standard deviation are studied. The randomness in the pedestrians’ motion allows separating between different phases of movement, which in the end, drives the dynamics. Our study allows to distinguish among emergent collective phenomena, unpredictability, and unexpected Brownian type behavior in certain regimes, that occur in one-dimensional hallways, such as exists in airplanes, cinemas, massive sports events, etc. These findings may be relevant to evacuation procedures in the event of an emergency, where anxiety may compromise people’s performance and the effectiveness of the evacuation plan. Therefore, it could be highly useful to introduce these aspects in the simulation of pedestrian dynamics.

Geomagnetic imprinting predicts spatio-temporal variation in homing migration of pink and sockeye salmon.

Animals navigate using a variety of sensory cues, but how each is weighted during different phases of movement (e.g. dispersal, foraging, homing) is controversial. Here, we examine the geomagnetic and olfactory imprinting hypotheses of natal homing with datasets that recorded variation in the migratory routes of sockeye (Oncorhynchus nerka) and pink (Oncorhynchus gorbuscha) salmon returning from the Pacific Ocean to the Fraser River, British Columbia. Drift of the magnetic field (i.e. geomagnetic imprinting) uniquely accounted for 23.2% and 44.0% of the variation in migration routes for sockeye and pink salmon, respectively. Ocean circulation (i.e. olfactory imprinting) predicted 6.1% and 0.1% of the variation in sockeye and pink migration routes, respectively. Sea surface temperature (a variable influencing salmon distribution but not navigation, directly) accounted for 13.0% of the variation in sockeye migration but was unrelated to pink migration. These findings suggest that geomagnetic navigation plays an important role in long-distance homing in salmon and that consideration of navigation mechanisms can aid in the management of migratory fishes by better predicting movement patterns. Finally, given the diversity of animals that use the Earth's magnetic field for navigation, geomagnetic drift may provide a unifying explanation for spatio-temporal variation in the movement patterns of many species.

Stimulation within the cuneate nucleus suppresses synaptic activation of climbing fibers

Several lines of research have shown that the excitability of the inferior olive is suppressed during different phases of movement. A number of different structures like the cerebral cortex, the red nucleus, and the cerebellum have been suggested as candidate structures for mediating this gating. The inhibition of the responses of the inferior olivary neurons from the red nucleus has been studied extensively and anatomical studies have found specific areas within the cuneate nucleus to be target areas for projections from the magnocellular red nucleus. In addition, GABA-ergic cells projecting from the cuneate nucleus to the inferior olive have been found. We therefore tested if direct stimulation of the cuneate nucleus had inhibitory effects on a climbing fiber field response, evoked by electrical stimulation of the pyramidal tract, recorded on the surface of the cerebellum. When the pyramidal tract stimulation was preceded by weak electrical stimulation (5–20 μA) within the cuneate nucleus, the amplitude of the climbing fiber field potential was strongly suppressed (approx. 90% reduction). The time course of this suppression was similar to that found after red nucleus stimulation, with a peak suppression occurring at 70 ms after the cuneate stimulation. Application of CNQX (6-cyano-7-nitroquinoxaline-2,3-dione, disodium salt) on the cuneate nucleus blocked the suppression almost completely. We conclude that a relay through the cuneate nucleus is a possible pathway for movement-related suppression of climbing fiber excitability.

OC-089 Transient hiatus hernia during transient lower oesophageal sphincter relaxations

IntroductionIn hiatus hernia there is proximal displacement of the gastro-oesophageal junction (GOJ) relative to the crural diaphragm impairing barrier function. Fluoroscopic studies have indicated proximal migration of the GOJ during...

Intra-Observer Variability of Longitudinal Displacement and Intramural Shear Strain Measurements of the Arterial Wall Using Ultrasound Noninvasively in vivo

Using a recently developed high-resolution noninvasive ultrasonic method, we recently demonstrated that the intima-media complex of the common carotid artery show a bidirectional multiphasic longitudinal displacement of the same magnitude as the diameter change during the cardiac cycle. The longitudinal movement of the adventitial region was smaller, thus, we identified shear strain and, thus, shear stress, within the arterial wall. The aim of this study was to evaluate the intra-observer variability of measurement of the longitudinal displacement of the intima-media complex and the intramural shear strain of the common carotid artery in vivo using the new ultrasonic method. The evaluation was carried out by comparing two consecutive measurements on the common carotid artery of 20 healthy human subjects. According to the method of Bland Altman, we show that the systematic and random differences for the different phases of movement are acceptable in comparison to the measured displacement and no significant differences between the two measurements could be detected ( p > 0.05 for all measured parameters). The coefficient of variation (CV) for measurement of the different phases of movement was ≤16%, including short-term physiologic variations. The higher variability in the measurement of the intramural shear strain (CV = 24%) has several explanations, which are discussed. In conclusion, this study shows that the present first ultrasonic method for high-resolution measurement of the longitudinal movement of the arterial wall is reliable and satisfactory for the further research of the longitudinal movement of the arterial wall in vivo. Further studies on the longitudinal movement of the arterial wall are important for developing an improved understanding of the physiology and the pathophysiology of the cardiovascular system. (E-mail: magnus.cinthio@elmat.lth.se)

Commentary

HIGHLIGHTED TOPICSNeural Control of MovementCommentaryGary C. SieckGary C. SieckPublished Online:01 May 2004https://doi.org/10.1152/japplphysiol.00211.2004MoreSectionsPDF (10 KB)Download PDF ToolsExport citationAdd to favoritesGet permissionsTrack citations ShareShare onFacebookTwitterLinkedInEmailWeChat Studies over the past 20 years have shown that, far from being immutable, spinal reflexes vary at different phases of movement and differ by task. The first featured article in this issue of the Journal, “Spinal reciprocal inhibition in human locomotion,” by Dr. A. Kido and colleagues (1), examines spinal inhibition during different locomotor tasks. This study represents the first of its kind to examine reciprocal inhibition in running as well as in standing and walking. When standing still, stretch reflexes help stabilize the body, and there is relatively high gain to correct small perturbations. During walking, stretch reflexes turn on and off at different phases of the step cycle but are generally lower than when standing still. Although reflexes likely provide only a fraction of the force needed to push the body off the ground, they may play important roles in modulating the amount of force needed for locomotion across different ground surfaces. Whereas previous studies have addressed the important roles of these reflexes in the control of movement, reciprocal inhibition has been less studied, and some controversy exists as to whether it is modulated at all during the step cycle. To clarify this issue, these investigators studied reciprocal inhibition in an antagonistic pair of human calf muscles, soleus and tibialis anterior, at speeds ranging from 0 (standing) to 9 km/h (running). They found that reciprocal inhibition decreased substantially with speed and to a lesser extent with task (e.g., running vs. walking at the same speed of 6 km/h). The functional significance of this modulation remains uncertain, but, clearly, as this study illustrates, different spinal reflexes are individually modulated, depending on the particular requirements of the reflex involved in a task such as locomotion.In the second featured article, entitled “Simultaneous control of hand displacements and rotations in orientation-matching experiments,” Drs. E. Torres and D. Zipser (2) address the independence of the spatial and temporal components of voluntary motion. The basis for this study was a recently proposed theoretical framework that suggests a geometric stage between sensory perception and motor action that functions as a brain mechanism to simulate goal-directed behavior without actual implementation. These investigators employed a simple but unconstrained orientation-matching experiment that revealed that simultaneous control of hand transport and rotation is robust to changes in speed, initial arm configuration, and target orientation. This finding is consistent with this theoretical framework and suggests that learning to produce a new geometric, time-independent strategy and learning to become proficient in the temporal domain of motion are distinct processes. Consequently, the smoothness and gracefulness of automatic movements can develop independently of geometric path. Such independence implies that an area of the brain is responsible for encoding the time-free directional signal this method proposes. An ideal candidate appears to be the posterior parietal cortex, a highly cognitive area where neural correlates of several of the key ingredients necessary for simulating this type of geometric motion in the brain are known to coexist. Such signals include those related to sensory goals (for defining the target of action), arm geometry (for enabling task-dependent metric identification), and coordinate transformations (for building smooth-differentiable maps). In addition, movement intentions in the absence of motion and a dynamics-free representation of movement previously described in this region are consistent with time-free representation of movement. This theoretical framework will not only serve to pose new questions about the formation of cognitive strategies in complex motions at both the behavioral and neurophysiological levels but will also provide the tools suitable for analysis of such high-dimensional spaces. References 1 Kido A, Naofumi T, and Stein RB. Spinal reciprocal inhibition in human locomotion. J Appl Physiol 96: 1969-1977, 2004.Link | ISI | Google Scholar2 Torres EB and Zipser D. Simultaneous control of hand displacements and rotations in orientation-matching experiments. J Appl Physiol 96: 1978-1987, 2004.Link | ISI | Google Scholar Download PDF Previous Back to Top Next FiguresReferencesRelatedInformation More from this issue > Volume 96Issue 5May 2004Pages 1968-1968 Copyright & PermissionsCopyright © 2004 the American Physiological Societyhttps://doi.org/10.1152/japplphysiol.00211.2004History Published online 1 May 2004 Published in print 1 May 2004 Metrics

Seasonal movements and foraging areas of adult southern female elephant seals, Mirounga leonina, from Marion Island

Seasonal movements and foraging areas of postbreeding (n = 9) and postmoulting (n = 3) adult southern elephant seal females from Marion Island were studied using Geolocation Time-depth Recorders. Movements were classified into three phases – an outbound transit phase, distant foraging phase, and an inbound transit phase. The longest residence time of postbreeding females during their foraging migrations was in areas at the outer edge of their feeding range (± 1460 km) both to the north and south of the island, largely within inter-frontal zones south of the Antarctic Polar Front (APF) and between the Sub-Tropical Convergence (STC) and the Sub-Antarctic Front (SAF). Postmoulting females travelled further afield (2122–3133 km distant) to the APF, to inter-frontal zones south of the APF (within the pack ice outer edge), as well as to the Antarctic Continental Shelf. This study provides additional information on the putative function of dive types in relation to the movement phases of elephant seal females from Marion Island. The relative frequency of assumed ‘foraging’, ‘exploratory’ and ‘transit’ dive types, as well as the duration and location of the different phases of movement suggest two seasonal foraging strategies. Sea floor topography could possibly cue the transit phases of both postbreeding and postmoulting females from Marion Island.

An approach to the functional anatomy of the sacroiliac joints in vivo.

This first part of this paper is a review of the literature on the functional anatomy of the sacroiliac joint followed by a preliminary biomechanical study of the fresh post mortem pelvis. The latter was done in order to determine the coefficients of the screw matrix and the position of the instantaneous centers of rotation during the symmetrical movements of nutation and contranutation simulated in the biomechanics laboratory. The main part of this work deals with the spatial analysis in vivo of the relative displacements of the iliac bones with respect to the sacrum in the course of dissymmetrical movements of the pelvis. In the different phases of movement, the roentgenographic observation of the position of the bony components with respect to a three-dimensional orthonormal reference system required the use of material based on the principles of photogrammetry. This technique was used to achieve spatial reconstruction of the data recovered from a series of orthogonal x-ray films of the sacroiliac joints. Data retrieval was carried out on a digital table linked to a computer with a graphic terminal so that the information could be displayed in the form of rectangular coordinates of defined points on the bone. Owing to the limited amplitude of articular displacement, a statistical study was required to retrieve the coordinates from the projection of these points on the X-ray film with an estimated threshold of significance of 0.1 and an error of +/- 0.1 mm.(ABSTRACT TRUNCATED AT 250 WORDS)

Induction of spreading during fibroblast movement.

This paper describes the phenomenon of retraction-induced spreading of embryonic chick heart fibroblasts moving in culture. Measurable criteria of cell spreading (increase in area of the spreading lamella, and total spread area of the cell) are found to change predictably with retraction of a portion of the cell margin. Ruffling activity was found to increase. The leading lamella of a spread fibroblast ordinarily advances slowly, with an average area increase of approximately 21 mu2m/min. A 10- to 30-fold increase in spreading occurs within 8 s after onset of retraction at the trailing edge and then decreases slightly so that by 1 min the increase in spreading is five to tenfold. During this period, there is a linear relationship between area increase at the leading edge and area decrease at the trailing edge. During the next 10--15 min, spreading gradually decreases to normal. Although the relationship between area spreading and area retracting of fibroblasts at different phases of movement is not significantly linear, it is highly correlated (Table II). These results suggest that the rate of fibroblast spreading may be inversely related to the degree of spreading of the cell as a whole.

Velocity Curves and Static Strength-Action Strength Correlations in Relation to the Mass Moved by the Arm

Abstract Tests were made with the hand carrying weights of 0.2, 3.1, and 16.6 kg. during a 72° horizontal adductive arm swing of maximal speed timed at 12° intervals. Five practice swings and 20 trials, under each condition, were performed by 60 male subjects. Reliability coefficients were high. The first 24° of movement exhibited declining acceleration, followed by linearly increasing acceleration for the 24°—60° interval and deceleration for the next 12°. Compared with static strength in the movement position, action strength computed from acceleration was much greater with the heaviest weight and considerably less with the light weights. The correlation between static strength and speed was quite low for the normal arm swing but increased with added weight, becoming r = .76 for the heaviest. There was little correlation of individual differences in speed between different phases of movement or between movements with light and heavy weights. Specificity was high, although correlations were made for atte...

Historical Notes on X-Ray Cinematography

The history of the various attempts to make x-ray movies is briefly traced. In the beginning there was only visual examination. When it became possible to take still x-ray photographs, the next step was to “animate” them by producing a series of stills showing different phases of movement. — With improvements in x-ray apparatus and reinforcement screens the time of exposure was reduced so that it became possible to take a series of x-ray photographs on a long strip of film. Speeds up to four pictures per second have been reached, though one experimenter claims speeds up to fourteen frames a second. — The “frames” so taken are copied on 35-mm. or 16-mm. film and shown in regular equipment. The 16-mm. display device described attracted great interest at the Chicago Century of Progress Fair and has since excited like interest at other popular expositions. — The methods employed to animate x-ray films are not only of historical importance, but were of considerable legal importance in connection with patent litigation on regular motion picture animation processes.