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Sample records for inaccurate grip force

  1. Adjustment of gripping force by optical systems

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    Jalba, C. K.; Barz, C.

    2018-01-01

    With increasing automation, robotics also requires ever more intelligent solutions in the handling of various tasks. In this context, many grippers must also be re-designed. For this, they must always be adapted for different requirements. The equipment of the gripper systems with sensors should help to make the gripping process more intelligent. In order to achieve such objectives, optical systems can also be used. This work analyzes how the gripping force can be adjusted by means of an optical recognition. The result of this work is the creation of a connection between optical recognition, tolerances, gripping force and real-time control. In this way, algorithms can be created, with the aid of which robot grippers as well as other gripping systems become more intelligent.

  2. ASSESSMENT OF GRIP FORCE CONTROL IN PATIENTS WITH MUSCULAR DYSTROPHY

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    Gregorij Kurillo

    2004-12-01

    Full Text Available Background. The majority of hand functionality tests are based on qualitative assessment which largely depends on the experience of the therapist. Computer-assisted methods can provide more objective and accurate measurements of the grip force and other parameters related to grasping.Methods. We analysed the grip force control in 12 patients with muscular dystrophy using the tracking system developed. The system consists of a grip-measuring device with endobjects assessing the force applied in different grips. The device was used as input to a tracking task where the patient applied the grip force according to the visual feedback from the computer screen. Each patient performed two tasks which consisted of tracking a ramp and sinus target.Results. We analysed the maximal grip force as assessed in the ramp task and the tracking accuracy of the sinus task. The results are compared among five different grips (cylindrical, lateral, palmar, pinch and spherical grip, applied with dominant and non-dominant hand. The results show no significant difference in tracking accuracy between the dominant and non-dominant hand.Conclusions. The results obtained in tracking the ramp target showed that the method could be used for the assessment of the muscle fatigue, providing quantitative information on muscle capacity. The results of the sinus-tracking task showed that the method can evaluate the grip force control in different types of grips, providing information on hand dexterity, muscle activation patterns or tremor.

  3. Basal Ganglia Mechanisms Underlying Precision Grip Force Control

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    Prodoehl, Janey; Corcos, Daniel M.; Vaillancourt, David E.

    2009-01-01

    The classic grasping network has been well studied but thus far the focus has been on cortical regions in the control of grasping. Sub-cortically, specific nuclei of the basal ganglia have been shown to be important in different aspects of precision grip force control but these findings have not been well integrated. In this review we outline the evidence to support the hypothesis that key basal ganglia nuclei are involved in parameterizing specific properties of precision grip force. We revi...

  4. Basal ganglia mechanisms underlying precision grip force control.

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    Prodoehl, Janey; Corcos, Daniel M; Vaillancourt, David E

    2009-06-01

    The classic grasping network has been well studied but thus far the focus has been on cortical regions in the control of grasping. Sub-cortically, specific nuclei of the basal ganglia have been shown to be important in different aspects of precision grip force control but these findings have not been well integrated. In this review, we outline the evidence to support the hypothesis that key basal ganglia nuclei are involved in parameterizing specific properties of precision grip force. We review literature from different areas of human and animal work that converges to build a case for basal ganglia involvement in the control of precision gripping. Following on from literature showing anatomical connectivity between the basal ganglia nuclei and key nodes in the cortical grasping network, we suggest a conceptual framework for how the basal ganglia could function within the grasping network, particularly as it relates to the control of precision grip force.

  5. Coordination of Fingertip Forces During Precision Grip in Premanifest Huntington’s Disease

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    Rao, Ashwini K.; Gordon, Andrew M.; Marder, Karen S.

    2011-01-01

    Precision grip control is important for accurate object manipulation and requires coordination between horizontal (grip) and vertical (load) fingertip forces. Manifest Huntington’s disease (HD) subjects demonstrate excessive and highly variable grip force and delayed coordination between grip and load forces. Because the onset of these impairments is unknown, we examined precision grip control in premanifest HD (pre-HD) subjects. Fifteen pre-HD and 15 age- and sex-matched controls performed the precision grip task in a seated position. Subjects grasped and lifted an object instrumented with a force transducer that measured horizontal grip and vertical load forces. Outcomes were preload time, loading time, maximum grip force, mean static grip force, and variability for all measures. We compared outcomes across groups and correlated grip measures with the Unified Huntington’s Disease Rating Scale and predicted age of onset. Variability of maximum grip force (P disease severity because they were correlated with predicted onset of disease. PMID:21394785

  6. Power grip force is modulated in repeated elbow movement.

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    Gao, Fan

    2012-01-01

    The objective of this study was to quantitatively investigate the modulation of power grip force under repeated elbow movement and its relation to muscle cocontraction and potential risk of developing cumulative trauma disorders (CTD). Thirteen right-handed participants without any neuromuscular disorders were recruited. Participants were instructed to hold a digital dynamometer in the hand with three levels of grip forces (20%, 40% and 60% of the maximum grip force) and perform repeated arm movement in the sagittal plane at three speeds (slow, self-paced and fast) with the upper arm voluntarily held by side by the participant. With the increase of motion rate and target force level, the grip force fluctuation, finger flexor muscle activities, elbow muscles cocontraction and apparent stiffness were significantly increased (p movement be avoided as much as possible in the workplace. Power grip is usually accompanied with arm movement in workplaces and the increased physical demand might result in higher muscle activities and potentially higher risk of repetitive musculoskeletal injuries.

  7. Spatio-Temporal Human Grip Force Analysis via Sensor Arrays

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    Florian P. Kolb

    2009-08-01

    Full Text Available This study describes a technique for measuring human grip forces exerted on a cylindrical object via a sensor array. Standardised resistor-based pressure sensor arrays for industrial and medical applications have been available for some time. We used a special 20 mm diameter grip rod that subjects could either move actively with their fingers in the horizontal direction or exert reactive forces against opposing forces generated in the rod by a linear motor. The sensor array film was attached to the rod by adhesive tape and covered approximately 45 cm2 of the rod surface. The sensor density was 4/cm2 with each sensor having a force resolution of 0.1 N. A scan across all sensors resulted in a corresponding frame containing force values at a frame repetition rate of 150/s. The force value of a given sensor was interpreted as a pixel value resulting in a false-colour image. Based on remote sensed image analysis an algorithm was developed to distinguish significant force-representing pixels from those affected by noise. This allowed tracking of the position of identified fingers in subsequent frames such that spatio-temporal grip force profiles for individual fingers could be derived. Moreover, the algorithm allowed simultaneous measurement of forces exerted without any constraints on the number of fingers or on the position of the fingers. The system is thus well suited for basic and clinical research in human physiology as well as for studies in psychophysics.

  8. Visual size cues in the programming of manipulative forces during precision grip.

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    Gordon, A M; Forssberg, H; Johansson, R S; Westling, G

    1991-01-01

    A size-weight illusion was used to examine the role of visual cues in the programming of manipulative forces during the lifting of test objects utilizing the precision grip. Three different boxes of equal weight and unequal size were lifted. These were equipped with an instrumented grip handle to measure the employed grip force, load force (vertical lifting force), force rates and vertical movement. All fifteen subjects participating in the study reported that the smallest box was the heaviest, which is consistent with size-weight illusion predictions. However, the rate of increase of the isometric grip and load forces initially during the lift, the peaks of the grip and load force and the vertical acceleration were all found to increase with the box size. Thus, despite the conscious perception indicating a heavier weight for the small object, the motor program was scaled for a lighter weight. Yet, no differences were found in grip force during the static phase of the lift, where weight related information was apparently available via sensory feedback. Previous studies have reported that the programming of the precision grip is based on somatosensory information gained during previous lifts (Johansson and Westling 1984, 1988a, b). The present study suggests that visual cues are integrated in the programming of manipulative forces during precision grip.

  9. Anticipatory grip force between 1 and 3g

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    White, Olivier; Van Loon, ing.. Jack J. W. A.; Thonnard, Jean-Louis; Hermsdorfer, Joachim; Lefevre, Philippe

    One remarkable capacity of utilizing common tools appropriately as soon as we grasp them relies on the ability to determine in advance the grip force (GF) required to handle them in relation to their mechanical properties and the surrounding environment. This anticipatory strategy avoids the uncompressible delays in the feedback system. The predictive control of GF is made possible because the nervous system can learn, store and then select the internal representations of the dynamics of innumerable objects, known as internal models. Beside this flexibility, the nervous system's ability to learn different task dynamics is often limited in classical robotic experiments The environment itself can be profoundly modified in altered gravity or centrifugation. The few studies that investigated motor adaptation in such contexts did not consider the interaction between gravitational phases and even less the transitions across environments. Here, we tested subject's abilities to adapt to levels of gravitational fields generated by a human centrifuge. In Experiment 1, seven subjects performed 4 lifting trials in each gravitational phase (1 to 2.5g and then 2.5 to 1g by steps of 0.5g) with a 0.12 kg instrumented object. In Experiment 2, six subjects performed vertical oscillations of the object during transitions between 1 and 3g (0.5g steps, ascending and descending phases, profile repeated twice). We continuously measured GF, load force (LF) and ambient gravity. We hypothesized that participants were able to predictively adjust GF to the new environment. In Experiment 1, participants adjusted their GF proportionally to gravity and decreased GF across trials within a given gravitational environment. Preload phases decreased over time from 300ms to 50ms irrespective of gravity. We quantified the abilities of participants to switch across environments by subtracting GF recorded in the last trial in the current gravity level from GF during the first trial in the new environment

  10. How dependent are grip force and arm actions during holding an object?

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    Danion, F

    2004-09-01

    In everyday life, when manipulating objects, arm actions and precision grip force are tightly coupled by the central nervous system. To investigate the extent of this neural coupling, 11 subjects were asked to perform tasks that encourage either the coupling (Task 1) or the dissociation (Task 2 and 3) of grip force and arm actions. During Task 1, subjects held a grasping device, with an extra load suspended underneath by a string. Then, using the other hand, subjects were asked to lift or release the suspended load, while maintaining unaffected the posture of the grasping arm. During Task 2, while holding the device, subjects received similar instructions, but this time the extra load was suspended underneath the forearm. During Task 3, subjects were explicitly asked to modulate their grip force without moving the arm. In Task 1, grip force changed in parallel with, or slightly ahead of, changes in load, which is consistent with the view of a feedforward mechanism making grip force largely subordinate to ongoing arm actions. In Task 2, even though subjects had no obvious reasons to modulate their force (i.e. the load of the device was constant) they did so, with a number of features that resemble performance in Task 1. In Task 3, as expected, voluntary modulations in grip force had no effect on arm actions. It is concluded that the neural coupling between arm actions and grip force (1) can possibly lead to clumsy reactions, (2) depends on the focal action, and (3) is only unidirectional.

  11. Relations between the inflection point on the force-time curve and force-time parameters during static explosive grip.

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    Ikemoto, Yukio; Demura, Shinichi; Yamaji, Shunsuke

    2004-04-01

    Individual differences in muscle contractile speed during static explosive muscle contraction are reflected in the developmental phase of the force-time curve. The purposes of this study were to clarify the properties and reliability of the inflection point of force-time, statistically dividing speed during static explosive grip into two phases and to assess the relations between that inflection point and others. Static explosive grip data were measured two times with a 5-min. rest (sampling frequency; 100 Hz). 32 healthy, young men (age: 15.5 +/- 0.8 yr., height: 173.9 +/- 7.3 cm, body mass: 71.5 +/- 11.2 kg) participated. 8 static explosive grip parameters were selected: time of reaching, integrated area, and quotient values of the integrated areas up to 0.25, 0.5, and 1.0 sec. divided by maximal grip force. The inflection point was calculated statistically from two regression lines fitted to a developmental phase and the almost steady-state phase of reaching maximal grip force by applying a two-phase regression model. The reliabilities of maximal grip force, time of reaching 90% of maximal grip force, and the integrated area until 0.5 sec. and 1.0 sec. after the onset of grip were good (ICC=.77 to .93). The time of reaching an inflection force value appeared at 0.3 sec. after the onset of grip, corresponding to 80% of maximal grip force, and the reliabilities of the parameters regarding inflection point were good (ICC=.77 to .95). The time determined by boundary data between the former and the latter regression data set and the regression coefficient during the developmental phase correlated significantly with the time of reaching 90% of maximal grip force, the integrated area, and the quotient values of the integrated areas up to 0.25, 0.5, and 1.0 sec. divided by maximal grip force (rs=-.78 to -.96 and -.75 to 0.88, respectively, pforce. A force during the developmental phase and maximal grip force can depend on different physiological factors. The time

  12. Adaptive grip force is modulated by subthalamic beta activity in Parkinson's disease patients

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    Lukas L. Imbach

    2015-01-01

    Conclusion: The time-locked suppression of beta oscillatory activity in the STN is in line with previous reports of beta ERD prior to voluntary movements. Our results show that the STN is involved in anticipatory grip force control in PD patients. The difference in the phasic beta ERD between the two tasks and the reduction of cortico-subthalamic synchronization suggests that qualitatively different neuronal network states are involved in different grip force control tasks.

  13. Manual action verbs modulate the grip force of each hand in unimanual or symmetrical bimanual tasks.

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    da Silva, Ronaldo Luis; Labrecque, David; Caromano, Fátima Aparecida; Higgins, Johanne; Frak, Victor

    2018-01-01

    Manual action verbs modulate the right-hand grip force in right-handed subjects. However, to our knowledge, no studies demonstrate the ability to accomplish this modulation during bimanual tasks nor describe their effect on left-hand behavior in unimanual and bimanual tasks. Using load cells and word playlists, we evaluated the occurrence of grip force modulation by manual action verbs in unimanual and symmetrical bimanual tasks across the three auditory processing phases. We found a significant grip force increase for all conditions compared to baseline, indicating the occurrence of modulation. When compared to each other, the grip force variation from baseline for the three phases of both hands in the symmetrical bimanual task was not different from the right-hand in the unimanual task. The left-hand grip force showed a lower amplitude for auditory phases 1 and 2 when compared to the other conditions. The right-hand grip force modulation became significant from baseline at 220 ms after the word onset in the unimanual task. This moment occurred earlier for both hands in bimanual task (160 ms for the right-hand and 180 for the left-hand). It occurred later for the left-hand in unimanual task (320 ms). We discuss the hypothesis that Broca's area and Broca's homologue area likely control the left-hand modulation in a unilateral or a bilateral fashion. These results provide new evidence for understanding the linguistic function processing in both hemispheres.

  14. Manual action verbs modulate the grip force of each hand in unimanual or symmetrical bimanual tasks.

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    Ronaldo Luis da Silva

    Full Text Available Manual action verbs modulate the right-hand grip force in right-handed subjects. However, to our knowledge, no studies demonstrate the ability to accomplish this modulation during bimanual tasks nor describe their effect on left-hand behavior in unimanual and bimanual tasks. Using load cells and word playlists, we evaluated the occurrence of grip force modulation by manual action verbs in unimanual and symmetrical bimanual tasks across the three auditory processing phases. We found a significant grip force increase for all conditions compared to baseline, indicating the occurrence of modulation. When compared to each other, the grip force variation from baseline for the three phases of both hands in the symmetrical bimanual task was not different from the right-hand in the unimanual task. The left-hand grip force showed a lower amplitude for auditory phases 1 and 2 when compared to the other conditions. The right-hand grip force modulation became significant from baseline at 220 ms after the word onset in the unimanual task. This moment occurred earlier for both hands in bimanual task (160 ms for the right-hand and 180 for the left-hand. It occurred later for the left-hand in unimanual task (320 ms. We discuss the hypothesis that Broca's area and Broca's homologue area likely control the left-hand modulation in a unilateral or a bilateral fashion. These results provide new evidence for understanding the linguistic function processing in both hemispheres.

  15. Probabilistic information on object weight shapes force dynamics in a grip-lift task.

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    Trampenau, Leif; Kuhtz-Buschbeck, Johann P; van Eimeren, Thilo

    2015-06-01

    Advance information, such as object weight, size and texture, modifies predictive scaling of grip forces in a grip-lift task. Here, we examined the influence of probabilistic advance information about object weight. Fifteen healthy volunteers repeatedly grasped and lifted an object equipped with a force transducer between their thumb and index finger. Three clearly distinguishable object weights were used. Prior to each lift, the probabilities for the three object weights were given by a visual cue. We examined the effect of probabilistic pre-cues on grip and lift force dynamics. We expected predictive scaling of grip force parameters to follow predicted values calculated according to probabilistic contingencies of the cues. We observed that probabilistic cues systematically influenced peak grip and load force rates, as an index of predictive motor scaling. However, the effects of probabilistic cues on force rates were nonlinear, and anticipatory adaptations of the motor output generally seemed to overestimate high probabilities and underestimate low probabilities. These findings support the suggestion that anticipatory adaptations and force scaling of the motor system can integrate probabilistic information. However, probabilistic information seems to influence motor programs in a nonlinear fashion.

  16. Adaptive control of grip force to compensate for static and dynamic torques during object manipulation.

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    Crevecoeur, F; Giard, T; Thonnard, J-L; Lefèvre, P

    2011-12-01

    Manipulating a cup by the handle requires compensating for the torque induced by the moment of the mass of the cup relative to the location of the handle. In the present study, we investigated the control strategy of subjects asked to perform grip-lift movements with an object with center of mass located away from the grip axis. Participants were asked to lift the manipulandum with a two-fingers precision grip and stabilize it in front of a visual target. Subjects showed a gradual and slow adaptation of the grip-force scaling across trials: the grip force tended to decrease slowly, and the temporal coordination between grip-force and load-torque rates displayed gradually, better-coordinated patterns. Importantly, this adaptation was much slower than the stabilization of the same parameters measured either when no torque came into play or after previous adaptation to the presence of a torque. In contrast, the maximum rotation induced by the torque was controlled efficiently after only few trials, and an unexpected decrease in the tangential torque produced significant overcompensation. An unexpected increase in torque produced a consistent opposite effect. This shows that the compensation for the dynamic torque was based on an anticipatory, dynamic counter-torque produced by the arm and wrist motor commands. The comparatively slow stabilization of grip-force control suggests a specific adaptation process engaged by the presence of the torque. This paradigm, including tangential torques, clearly constitutes a powerful tool to extract the adaptive component of grip control during object manipulation.

  17. Grip force is part of the semantic representation of manual action verbs.

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    Frak, Victor; Nazir, Tatjana; Goyette, Michel; Cohen, Henri; Jeannerod, Marc

    2010-03-16

    Motor actions and action verbs activate similar cortical brain regions. A functional interference can be taken as evidence that there is a parallel treatment of these two types of information and would argue for the biological grounding of language in action. A novel approach examining the relationship between language and grip force is presented. With eyes closed and arm extended, subjects listened to words relating (verbs) or not relating (nouns) to a manual action while holding a cylinder with an integrated force sensor. There was a change in grip force when subjects heard verbs that related to manual action. Grip force increased from about 100 ms following the verb presentation, peaked at 380 ms and fell abruptly after 400 ms, signalling a possible inhibition of the motor simulation evoked by these words. These observations reveal the intimate relationship that exists between language and grasp and show that it is possible to elucidate online new aspects of sensorimotor interaction.

  18. Grip force is part of the semantic representation of manual action verbs.

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    Victor Frak

    Full Text Available Motor actions and action verbs activate similar cortical brain regions. A functional interference can be taken as evidence that there is a parallel treatment of these two types of information and would argue for the biological grounding of language in action. A novel approach examining the relationship between language and grip force is presented. With eyes closed and arm extended, subjects listened to words relating (verbs or not relating (nouns to a manual action while holding a cylinder with an integrated force sensor. There was a change in grip force when subjects heard verbs that related to manual action. Grip force increased from about 100 ms following the verb presentation, peaked at 380 ms and fell abruptly after 400 ms, signalling a possible inhibition of the motor simulation evoked by these words. These observations reveal the intimate relationship that exists between language and grasp and show that it is possible to elucidate online new aspects of sensorimotor interaction.

  19. The properties and interrelationships of various force-time parameters during maximal repeated rhythmic grip.

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    Nakada, Masakatsu; Demura, Shinichi; Yamaji, Shunsuke

    2007-01-01

    The purpose of this study was to examine the properties and interrelationships of various force-time parameters including the inflection point for the rate of decline in force during a maximal repeated rhythmic grip. Fifteen healthy males (age M=21.5, SD=2.1 yr, height M=172.4, SD=5.7 cm, body mass M=68.2, SD=9.2 kg) participated in this study. Subjects performed a maximal repeated rhythmic grip with maximal effort with a target frequency of 30 grip.min(-1) for 6 min. The force value decreased linearly and markedly until about 70% of maximal strength for about 55 s after the onset of a maximal repeated rhythmic grip, and then decreased moderately. Because all parameters showed fair or good correlations between 3 min and 6 min, they are considered to be able to sufficiently evaluate muscle endurance for 3 min instead of 6 min. However, there were significant differences between 3 min and 6 min in the integrated area, the final force, the rate of the decrement constant (k) fitting the force decreasing data to y=ae(-kx)+b and the force of maximal difference between the force and a straight line from peak force to the final force. Their parameters may vary generally by the length of a steady state, namely, a measurement time. The final force value before finishing and the rate of the decrement constant (k) reflect the latter phase during a maximal repeated rhythmic grip. Although many parameters show relatively high mutual relationships, the rate constant (k) shows relatively low correlations with other parameters. We inferred that decreasing the time until 80% of maximal strength and the amount of the decrement force for the first 1 min reflect a linear decrease in the initial phase.

  20. Coordination of hand grip and load forces in uni- and bidirectional static force production tasks.

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    Jaric, Slobodan; Russell, Elizabeth M; Collins, Jeffrey J; Marwaha, Rahul

    The purpose of the study was to explore the differences in coordination of grip (G) and load forces (L) in a unidirectional and bidirectional bimanual static force production task. Subjects (N=10) exerted oscillatory isometric L profiles against an externally fixed hand-held device, modulated either in pure tension (unidirectional) or in alternating tension and compression (bidirectional) at a rate of either 1.33 or 2.67 Hz. The unidirectional task revealed a high level of coordination of both the ipsilateral (i.e., G and L of each hand) and contralateral pairs of forces (two Gs and two Ls) as assessed by correlation and stability of force ratios. The bidirectional task demonstrated a low level of inconsistently modulated Gs with respect to the change of L, which resulted in a deteriorated coordination, particularly between the ipsilateral forces. The overall effect of task on the force coordination was higher than the effect of frequency suggesting that the higher frequency of G modulation required in the bidirectional task is not likely to be the main cause of the observed phenomenon. We interpret these differences by a relative simplicity of the control mechanisms of the unidirectional task based on a single synergy of G and L muscles that allows simultaneous coordination of both the ipsilateral and contralateral forces. Due to the switching between two distinctive synergies involving G muscles, the bidirectional task could possess a higher control complexity causing a decoupled coordination of the ipsilateral forces, while retaining the coordination of contralateral forces at a relatively high level.

  1. Applying support vector regression analysis on grip force level-related corticomuscular coherence

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    Rong, Yao; Han, Xixuan; Hao, Dongmei

    2014-01-01

    to compare the corticomuscular coherence in the alpha (7–15Hz), beta (15–30Hz) and gamma (30–45Hz) band at 25 % maximum grip force (MGF) and 75 % MGF. Results show that ESVR could reduce the influence of deflected signals and summarize the overall behavior of multiple coherence curves. Coherence proportion...

  2. Modeling of the interaction between grip force and vibration transmissibility of a finger.

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    Wu, John Z; Welcome, Daniel E; McDowell, Thomas W; Xu, Xueyan S; Dong, Ren G

    2017-07-01

    It is known that the vibration characteristics of the fingers and hand and the level of grip action interacts when operating a power tool. In the current study, we developed a hybrid finger model to simulate the vibrations of the hand-finger system when gripping a vibrating handle covered with soft materials. The hybrid finger model combines the characteristics of conventional finite element (FE) models, multi-body musculoskeletal models, and lumped mass models. The distal, middle, and proximal finger segments were constructed using FE models, the finger segments were connected via three flexible joint linkages (i.e., distal interphalangeal joint (DIP), proximal interphalangeal joint (PIP), and metacarpophalangeal (MCP) joint), and the MCP joint was connected to the ground and handle via lumped parameter elements. The effects of the active muscle forces were accounted for via the joint moments. The bone, nail, and hard connective tissues were assumed to be linearly elastic whereas the soft tissues, which include the skin and subcutaneous tissues, were considered as hyperelastic and viscoelastic. The general trends of the model predictions agree well with the previous experimental measurements in that the resonant frequency increased from proximal to the middle and to the distal finger segments for the same grip force, that the resonant frequency tends to increase with increasing grip force for the same finger segment, especially for the distal segment, and that the magnitude of vibration transmissibility tends to increase with increasing grip force, especially for the proximal segment. The advantage of the proposed model over the traditional vibration models is that it can predict the local vibration behavior of the finger to a tissue level, while taking into account the effects of the active musculoskeletal force, the effects of the contact conditions on vibrations, the global vibration characteristics. Published by Elsevier Ltd.

  3. Differential representation of dynamic and static power grip force in the sensorimotor network.

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    Keisker, Birgit; Hepp-Reymond, Marie-Claude; Blickenstorfer, Armin; Kollias, Spyros S

    2010-04-01

    Previous studies investigating the blood oxygen level-dependent (BOLD) signal in the human sensorimotor cortex during static force (maintained for a few seconds) and dynamic force (repetitive force pulses) resulted in contradictory findings. Therefore, we conducted a whole-brain functional magnetic resonance imaging study during a visuomotor task requiring the production of either dynamic or static power grip force. Thereby we aimed at clarifying whether the BOLD signal behaves differently with dynamic and static force in the primary motor cortex, and whether it behaves in the same way in all areas and regions involved in force production. In the static condition, participants applied visually guided, isometric grip force on a dynamometer of 20% maximal voluntary contraction (MVC) and held this force for 21 s. In the dynamic condition, self-paced force pulses of 20% MVC were produced at a rate of 0.5 Hz. Static and dynamic force production activated an overlapping network of sensorimotor cortical and subcortical regions. However, the production of a significantly higher mean static force compared with the dynamic force resulted in a significantly smaller BOLD signal in the contralateral motor cortex, confirming observations of an earlier investigation. In addition, we found that the ipsilateral anterior cerebellum behaved similar to the motor cortex, whereas in all other activated regions the activation during static and dynamic force did not significantly differ. These findings demonstrate that various regions of the sensorimotor network participate differentially in the production and control of low static and dynamic grip force, and raise important questions concerning the interpretation of the BOLD signal with respect to mechanisms of neurovascular coupling.

  4. Moving objects with clumsy fingers: how predictive is grip force control in patients with impaired manual sensibility?

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    Nowak, Dennis A; Hermsdörfer, Joachim; Marquardt, Christian; Topka, Helge

    2003-03-01

    Anticipatory grip force adjustments to movement-induced load fluctuations of a hand-held object suggest that motion planning is based on an internal forward model of both the external object properties and the dynamics of the own motor apparatus. However, the central nervous system also refers to real time sensory feedback from the grasping digits in order to achieve a highly economical coupling between grip force and the actual loading requirements. We analyzed grip force control during vertical point-to-point arm movements with a hand-held instrumented object in 9 patients with moderately impaired tactile sensibility of the grasping digits due to chronic median nerve compression (n = 3), axonal (n = 3) and demyelinating sensory polyneuropathy (n = 3) in comparison to 9 healthy age- and sex-matched control subjects. Point-to-point arm movements started and ended with the object being held stationary at rest. Load force changes arose from inertial loads related to the movement. A maximum of load force occurred early in upward and near the end of downward movements. Compared to healthy controls, patients with impaired manual sensibility generated similar static grip forces during stationary holding of the object and similar force ratios between maximum grip and load force. These findings reflect effective grip force scaling in relation to the movement-induced loads despite reduced afferent feedback from the grasping digits. For both groups the maxima of grip and load force coincided very closely in time, indicating that the temporal regulation of the grip force profile with the load profile was processed with a similar high precision. In addition, linear regression analyses between grip and load forces during movement-related load increase and load decrease phases revealed a similar precise temporo-spatial coupling between grip and load forces for patients and controls. Our results suggest that the precise and anticipatory adjustment of the grip force profile to the

  5. Selective Linear-Regression Model for hand posture discrimination and grip force estimation using surface electromyogram signals.

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    Yamanoi, Yusuke; Morishita, Soichiro; Kato, Ryu; Yokoi, Hiroshi

    2015-01-01

    This paper proposes the method of hand posture discrimination and grip force estimation by means of Selective Linear-Regression Model. Generally, myoelectric hands which discriminate hand posture and estimate grip force at the same time result in unsatisfying results because of complication of EMG signals. Therefore, most of myoelectric hands can control either the force or the posture. However, the proposed method is able to discriminate hand posture and to estimate grip force simultaneously while the accuracy results are achieved. In experiments, EMG signals were measured while hand posture and grip force were changing. As a result, it appears that EMG features increase monotonically with grip force. In addition, increasing forms of EMG features are different on each posture. Based on these experimental results, the authors propose the method for both discriminating hand posture and estimating grip force by means of several linear-regression models which utilize the relationship between the grip force and EMG features on each posture. To evaluate the effectiveness of this method, the failure rates of discrimination and the estimation errors of the proposed method were employed. The results indicate that failure rates and estimation errors are improved significantly.

  6. The size of the visual size cue used for programming manipulative forces during precision grip.

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    Mon-Williams, M; Murray, A H

    2000-12-01

    We used a perturbation technique to quantify the contribution of visual size cues to the programming of target force when lifting an object. Our results indicate that the nervous system attaches a reasonable weight to visual size cues when programming the target grip force for a novel object. In a subsequent lift of the same object, however, the confidence attached to the visual size cue fell dramatically. It is not clear whether the decrease in the use of size information was accelerated by the presence of a cue conflict or whether the fall represents the normal shift towards the use of a memory-based representation for programming grip force. In a second experiment, we used the "size-weight illusion" to explore the relationship between the verbal report of an object's weight and the programming of the grip and load force. We found that erroneous motor programming (as indexed by a number of measures) was neither necessary nor sufficient for the size-weight illusion to occur. These findings call for a re-evaluation of a previous explanation for the size-weight illusion. We suggest that the illusion arises because the cognitive system attempts to rationalise the fact that objects of apparently equal density but different size feel as if they have the same weight.

  7. Development of force sensing circuit to determine the optimal force required for effective dynamic tripod grip/writing

    Science.gov (United States)

    Suraj S., S.; Kulkarni, Palash; Bokadia, Pratik; Ramanathan, Prabhu; Nageswaran, Sharmila

    2018-04-01

    Handwriting is a combination of fine motor perceptions and cognitive skills to produce words on paper. For writing, the most commonly used and recommended grip is the dynamic tripod grip. A child's handwriting starts developing during the times of pre-schooling and improves over time. While writing, children apply excessive force on the writing instrument. This force is exerted by their fingers and as per the law of reaction, the writing instruments tend to exert an equal and opposite force, that could damage the delicate soft tissue structures in their fingers and initiate cramps and pains. This condition is also prevalent in adults who tend to write for long hours under pressure. An example would be adolescence student during the exams. Clinically this condition is termed as `Writer's Cramp', which is usually characterized by muscle fatigue and pain in the fingers. By understanding and fixing the threshold of the force that should be exerted by the fingers while gripping the instrument, the pain can be controlled or avoided. This research aims in designing an electronic module which can help in understanding the threshold of pressure which is optimum enough to establish a better contact between the fingers and the instrument and should be capable of controlling or avoiding the pain. The design of FSR based electronic system is explained with its circuitry and results of initial testing is presented in this paper.

  8. Segregated and overlapping neural circuits exist for the production of static and dynamic precision grip force.

    Science.gov (United States)

    Neely, Kristina A; Coombes, Stephen A; Planetta, Peggy J; Vaillancourt, David E

    2013-03-01

    A central topic in sensorimotor neuroscience is the static-dynamic dichotomy that exists throughout the nervous system. Previous work examining motor unit synchronization reports that the activation strategy and timing of motor units differ for static and dynamic tasks. However, it remains unclear whether segregated or overlapping blood-oxygen-level-dependent (BOLD) activity exists in the brain for static and dynamic motor control. This study compared the neural circuits associated with the production of static force to those associated with the production of dynamic force pulses. To that end, healthy young adults (n = 17) completed static and dynamic precision grip force tasks during functional magnetic resonance imaging (fMRI). Both tasks activated core regions within the visuomotor network, including primary and sensory motor cortices, premotor cortices, multiple visual areas, putamen, and cerebellum. Static force was associated with unique activity in a right-lateralized cortical network including inferior parietal lobe, ventral premotor cortex, and dorsolateral prefrontal cortex. In contrast, dynamic force was associated with unique activity in left-lateralized and midline cortical regions, including supplementary motor area, superior parietal lobe, fusiform gyrus, and visual area V3. These findings provide the first neuroimaging evidence supporting a lateralized pattern of brain activity for the production of static and dynamic precision grip force. Copyright © 2011 Wiley Periodicals, Inc.

  9. Relationships between force and muscle oxygenation kinetics during sustained static gripping using a progressive workload.

    Science.gov (United States)

    Demura, Shinichi; Nakada, Masakatsu

    2009-01-01

    This study aimed to examine the relationships between force and subjective muscle-fatigue sensation (SMS), and muscle oxygenation kinetics during sustained static gripping using a progressive workload. Subjects consisted of 10 males (height 173.2+/-7.1 cm, body weight 70.3+/-15.1 kg, and age 21.1+/-1.5 years). They performed sustained static gripping with 7 gradually increasing relative demand values of 20% to 80% maximal voluntary contraction (MVC). The staging of the progressive workload was 10 s for 20% MVC, 20 s each for 30, 40, 50, 60, and 70% MVC, and 10 s for 80% MVC. Borg's SMS was used to measure the fatigue sensation of the antebrachial region in a pre-test and every 10 s during the test. The time to reach minimum Oxy-Hb/Mb appeared at about 50 s (52.6+/-25.2 s) after the onset of sustained static gripping, and the time to reach maximum Deoxy-Hb/Mb occurred later at 90 s. Significant and high correlations (r=0.632-0.721) were found between the time to reach maximum Deoxy-Hb/Mb, and Peak Force Time and Average Force. Even though the demand values caused a workload increase and reached 50% MVC, the change of Total Hb/Mb and Oxy-Hb/Mb kinetics was relatively small. Therefore, the effect caused by an obstruction of blood volume may not occur during the progressive workload. It was determined that the contraction time after the peak of SMS is relatively short and an individual difference in force value expands in the phase where SMS reaches its peak.

  10. Relationship between forced vital capacity and hand grip strength in children

    OpenAIRE

    Novák, Ondřej

    2017-01-01

    Title: Relationship between forced vital capacity and hand grip strength in children Objectives: One of goals of this thesis is to find out how strong is the connection between the strength of a children's handgrip and the FVC. Another aim is to ascertain what is the age limit to use a handgrip examination to estimate the children's FVC. The last goal is to determine whether a body height, weight and age of a child are crucial to evaluate the handgrip and the FVC. Methods: First part of this ...

  11. Quantification of hand function by power grip and pinch strength force measurements in ulnar nerve lesion simulated by ulnar nerve block.

    Science.gov (United States)

    Wachter, Nikolaus Johannes; Mentzel, Martin; Krischak, Gert D; Gülke, Joachim

    2017-06-24

    In the assessment of hand and upper limb function, grip strength is of the major importance. The measurement by dynamometers has been established. In this study, the effect of a simulated ulnar nerve lesion on different grip force measurements was evaluated. In 25 healthy volunteers, grip force measurement was done by the JAMAR dynamometer (Fabrication Enterprises Inc, Irvington, NY) for power grip and by a pinch strength dynamometer for tip pinch strength, tripod grip, and key pinch strength. A within-subject research design was used in this prospective study. Each subject served as the control by preinjection measurements of grip and pinch strength. Subsequent measurements after ulnar nerve block were used to examine within-subject change. In power grip, there was a significant reduction of maximum grip force of 26.9% with ulnar nerve block compared with grip force without block (P block: 57.5% in tip pinch strength (P block on grip and pinch force could be confirmed. However, the assessment of other dimensions of hand strength as tip pinch, tripod pinch and key pinch had more relevance in demonstrating hand strength changes resulting from an distal ulnar nerve lesion. The measurement of tip pinch, tripod grip and key pinch can improve the follow-up in hand rehabilitation. II. Copyright © 2017 Hanley & Belfus. Published by Elsevier Inc. All rights reserved.

  12. An Overview on Gripping Force Measurement at the Micro and Nano-Scales Using Two-Fingered Microrobotic Systems

    Directory of Open Access Journals (Sweden)

    Mokrane Boudaoud

    2014-03-01

    Full Text Available Two-fingered micromanipulation systems with an integrated force sensor are widely used in robotics to sense and control gripping forces at the micro and nano-scales. They became of primary importance for an efficient manipulation and characterization of highly deformable biomaterials and nanostructures. This paper presents a chronological overview of gripping force measurement using two-fingered micromanipulation systems. The work summarizes the major achievements in this field from the early 90s to the present, focusing in particular on the evolution of measurement technologies regarding the requirements of microrobotic applications. Measuring forces below the microNewton for the manipulation of highly deformable materials, embedding force sensors within microgrippers to increase their dexterity, and reducing the influence of noise to improve the measurement resolution are among the addressed challenges. The paper shows different examples of how these challenges have been addressed. Resolution, operating range and signal/noise ratio of gripping force sensors are reported and compared. A discussion about force measurement technologies and gripping force control is performed and future trends are highlighted.

  13. Effects of Anodal Transcranial Direct Current Stimulation on Visually Guided Learning of Grip Force Control

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    Tamas Minarik

    2015-03-01

    Full Text Available Anodal transcranial Direct Current Stimulation (tDCS has been shown to be an effective non-invasive brain stimulation method for improving cognitive and motor functioning in patients with neurological deficits. tDCS over motor cortex (M1, for instance, facilitates motor learning in stroke patients. However, the literature on anodal tDCS effects on motor learning in healthy participants is inconclusive, and the effects of tDCS on visuo-motor integration are not well understood. In the present study we examined whether tDCS over the contralateral motor cortex enhances learning of grip-force output in a visually guided feedback task in young and neurologically healthy volunteers. Twenty minutes of 1 mA anodal tDCS were applied over the primary motor cortex (M1 contralateral to the dominant (right hand, during the first half of a 40 min power-grip task. This task required the control of a visual signal by modulating the strength of the power-grip for six seconds per trial. Each participant completed a two-session sham-controlled crossover protocol. The stimulation conditions were counterbalanced across participants and the sessions were one week apart. Performance measures comprised time-on-target and target-deviation, and were calculated for the periods of stimulation (or sham and during the afterphase respectively. Statistical analyses revealed significant performance improvements over the stimulation and the afterphase, but this learning effect was not modulated by tDCS condition. This suggests that the form of visuomotor learning taking place in the present task was not sensitive to neurostimulation. These null effects, together with similar reports for other types of motor tasks, lead to the proposition that tDCS facilitation of motor learning might be restricted to cases or situations where the motor system is challenged, such as motor deficits, advanced age, or very high task demand.

  14. The relation between force and movement when grasping an object with a precision grip.

    Science.gov (United States)

    Biegstraaten, Marianne; Smeets, Jeroen B J; Brenner, Eli

    2006-05-01

    When reaching out for objects, the digits' paths curve so that they approach their positions of contact moving more or less perpendicularly to the local surface orientation. This increases the accuracy of positioning the digits and ensures that any forces exerted at contact are nearly perpendicular to the surface, so that friction will prevent the digits from slipping along the surface. When lifting the object a similar force perpendicular to the surface is needed to prevent the object from slipping from one's fingers. In order to determine whether these two issues are dealt with simultaneously we let subjects pick up a cube from three different starting positions and measured the digits' movements and forces from before contact until the moment the cube started moving. The impact force was low. After impact, the digits spent about 200 ms in contact with the surface of the cube before the latter started to move. The digits first decelerated, and then they gradually built up the grip- and lift forces to move the cube upwards. We found no direct relationship between the control of the reaching movement towards the object and the force applied at the surface of the object to pick it up. We conclude that the reaching and lifting movements are quite independent.

  15. Aging effects on the control of grip force magnitude: an fMRI study.

    Science.gov (United States)

    Noble, Jeremy W; Eng, Janice J; Kokotilo, Kristen J; Boyd, Lara A

    2011-06-01

    Functional neuroimaging techniques have allowed for investigations into the mechanisms of age-related deterioration in motor control. This study used functional Magnetic Resonance Imaging (fMRI) to investigate age related differences in the control of grip force magnitude. Using an event-related design, fMRI scans were completed on 13 older adults, and 13 gender matched younger adults, while using their dominant hand to squeeze a rubber bulb for 4s at 10%, 40% or 70% of their maximum voluntary contraction. Both groups were able to match the relative force targets, however the older adults produced significantly lower levels of absolute force. fMRI analysis consisted of a 1) region of interest (ROI) approach to detect differences in selected motor areas within brain and 2) a voxel-wise whole brain comparison to find areas of differential activation that were not defined a priori between the older and younger group. The ROI analysis revealed that despite producing lower levels of absolute force, the older adults showed higher levels of activity predominantly in subcortical structures (putamen, thalamus and cerebellum) when compared to the younger group. The older adults also showed higher levels of activity in the ipsilateral ventral premotor cortex. A total of 19 of the 22 ROIs analyzed showed a significant main effect of the required force-level. In the majority of the ROIs that showed a significant force effect there were no significant differences in the magnitude of the blood-oxygen-level-dependent (BOLD) signal between the 10% and 40% conditions but a significantly higher BOLD signal in the 70% condition, suggesting that the modulation of brain activation with grip force may not be controlled in a linear fashion. It was also found that the older adult group demonstrate higher levels of activation in 7 areas during a force production task at higher force levels using a voxel-wise analysis. The 7 clusters that showed significant differences tended to be areas

  16. Phalanx force magnitude and trajectory deviation increased during power grip with an increased coefficient of friction at the hand-object interface.

    Science.gov (United States)

    Enders, Leah R; Seo, Na Jin

    2011-05-17

    This study examined the effect of friction between the hand and grip surface on a person's grip strategy and force generation capacity. Twelve young healthy adults performed power grip exertions on an instrumented vertical cylinder with the maximum and 50% of maximum efforts (far above the grip force required to hold the cylinder), while normal and shear forces at each phalanx of all five fingers in the direction orthogonal to the gravity were recorded. The cylinder surface was varied for high-friction rubber and low-friction paper coverings. An increase in surface friction by replacing the paper covering with the rubber covering resulted in 4% greater mean phalanx normal force (perpendicular to the cylinder surface) and 22% greater mean phalanx shear force in either the proximal or distal direction of the digits (pfriction with the rubber surface compared to the paper surface was associated with a 20% increase in the angular deviation of the phalanx force from the direction normal to the cylinder surface (p<0.05). This study demonstrates that people significantly changed the magnitude and direction of phalanx forces depending on the surface they gripped. Such change in the grip strategy appears to help increase grip force generation capacity. This finding suggests that a seemingly simple power grip exertion involves sensory feedback-based motor control, and that people's power grip capacity may be reduced in cases of numbness, glove use, or injuries resulting in reduced sensation. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. Weight-specific anticipatory coding of grip force in human dorsal premotor cortex

    DEFF Research Database (Denmark)

    van Nuenen, Bart F L; Kuhtz-Buschbeck, Johann; Schulz, Christian

    2012-01-01

    , using either continuous theta burst stimulation (cTBS) at 80% (inhibitory cTBS) or 30% (sham cTBS) of active motor threshold. The conditioning effects of cTBS on preparatory brain activity were assessed with functional MRI, while participants lifted a light or heavy weight in response to a go-cue (S2......). An additional pre-cue (S1) correctly predicted the weight in 75% of the trials. Participants were asked to use this prior information to prepare for the lift. In the sham condition, grip force showed a consistent undershoot, if the S1 incorrectly prompted the preparation of a light lift. Likewise, an S1...... during object lifting....

  18. A method to study precision grip control in viscoelastic force fields using a robotic gripper.

    Science.gov (United States)

    Lambercy, Olivier; Metzger, Jean-Claude; Santello, Marco; Gassert, Roger

    2015-01-01

    Instrumented objects and multipurpose haptic displays have commonly been used to investigate sensorimotor control of grasping and manipulation. A major limitation of these devices, however, is the extent to which the experimenter can vary the interaction dynamics to fully probe sensorimotor control mechanisms. We propose a novel method to study precision grip control using a grounded robotic gripper with two moving, mechanically coupled finger pads instrumented with force sensors. The device is capable of stably rendering virtual mechanical properties with a wide dynamic range of achievable impedances. Eight viscoelastic force fields with different combinations of stiffness and damping parameters were implemented, and tested on eight healthy subjects performing 30 consecutive repetitions of a grasp, hold, and release task with time and position constraints. Rates of thumb and finger force were found to be highly correlated (r>0.9) during grasping, revealing that, despite the mechanical coupling of the two finger pads, subjects performed grasping movements in a physiological fashion. Subjects quickly adapted to the virtual dynamics (within seven trials), but, depending on the presented force field condition, used different control strategies to correctly perform the task. The proof of principle presented in this paper underscores the potential of such a one-degree-of-freedom robotic gripper to study neural control of grasping, and to provide novel insights on sensorimotor control mechanisms.

  19. Key Insights into Hand Biomechanics: Human Grip Stiffness Can Be Decoupled from Force by Cocontraction and Predicted from Electromyography

    Directory of Open Access Journals (Sweden)

    Hannes Höppner

    2017-05-01

    Full Text Available We investigate the relation between grip force and grip stiffness for the human hand with and without voluntary cocontraction. Apart from gaining biomechanical insight, this issue is particularly relevant for variable-stiffness robotic systems, which can independently control the two parameters, but for which no clear methods exist to design or efficiently exploit them. Subjects were asked in one task to produce different levels of force, and stiffness was measured. As expected, this task reveals a linear coupling between force and stiffness. In a second task, subjects were then asked to additionally decouple stiffness from force at these force levels by using cocontraction. We measured the electromyogram from relevant groups of muscles and analyzed the possibility to predict stiffness and force. Optical tracking was used for avoiding wrist movements. We found that subjects were able to decouple grip stiffness from force when using cocontraction on average by about 20% of the maximum measured stiffness over all force levels, while this ability increased with the applied force. This result contradicts the force–stiffness behavior of most variable-stiffness actuators. Moreover, we found the thumb to be on average twice as stiff as the index finger and discovered that intrinsic hand muscles predominate our prediction of stiffness, but not of force. EMG activity and grip force allowed to explain 72 ± 12% of the measured variance in stiffness by simple linear regression, while only 33 ± 18% variance in force. Conclusively the high signal-to-noise ratio and the high correlation to stiffness of these muscles allow for a robust and reliable regression of stiffness, which can be used to continuously teleoperate compliance of modern robotic hands.

  20. The role of left supplementary motor area in grip force scaling.

    Directory of Open Access Journals (Sweden)

    Olivier White

    Full Text Available Skilled tool use and object manipulation critically relies on the ability to scale anticipatorily the grip force (GF in relation to object dynamics. This predictive behaviour entails that the nervous system is able to store, and then select, the appropriate internal representation of common object dynamics, allowing GF to be applied in parallel with the arm motor commands. Although psychophysical studies have provided strong evidence supporting the existence of internal representations of object dynamics, known as "internal models", their neural correlates are still debated. Because functional neuroimaging studies have repeatedly designated the supplementary motor area (SMA as a possible candidate involved in internal model implementation, we used repetitive transcranial magnetic stimulation (rTMS to interfere with the normal functioning of left or right SMA in healthy participants performing a grip-lift task with either hand. TMS applied over the left, but not right, SMA yielded an increase in both GF and GF rate, irrespective of the hand used to perform the task, and only when TMS was delivered 130-180 ms before the fingers contacted the object. We also found that both left and right SMA rTMS led to a decrease in preload phase durations for contralateral hand movements. The present study suggests that left SMA is a crucial node in the network processing the internal representation of object dynamics although further experiments are required to rule out that TMS does not affect the GF gain. The present finding also further substantiates the left hemisphere dominance in scaling GF.

  1. Superposition of automatic and voluntary aspects of grip force control in humans during object manipulation.

    Science.gov (United States)

    Danion, Frederic

    2013-01-01

    When moving grasped objects, people automatically modulate grip force (GF) with movement-dependent load force (LF) in order to prevent object slip. However, GF can also be modulated voluntarily as when squeezing an object. Here we investigated possible interactions between automatic and voluntary GF control. Participants were asked to generate horizontal cyclic movements (between 0.6 and 2.0 Hz) of a hand-held object that was restrained by an elastic band such that the load force (LF) reached a peak once per movement cycle, and to simultaneously squeeze the object at each movement reversal (i.e., twice per cycle). Participants also performed two control tasks in which they either only moved (between 0.6 and 2.0 Hz) or squeezed (between 1.2 and 4.0 Hz) the object. The extent to which GF modulation in the simultaneous task could be predicted from the two control tasks was assessed using power spectral analyses. At all frequencies, the GF power spectra from the simultaneous task exhibited two prominent components that occurred at the cycle frequency (ƒ) and at twice this frequency (2ƒ), whereas the spectra from the movement and squeeze control task exhibited only single peaks at ƒ and 2ƒ, respectively. At lower frequencies, the magnitudes of both frequency components in the simultaneous task were similar to the magnitudes of the corresponding components in the control tasks. However, as frequency increased, the magnitudes of both components in the simultaneous task were greater than the magnitudes of the corresponding control task components. Moreover, the phase relationship between the ƒ components of GF and LF began to drift from the value observed in the movement control task. Overall these results suggest that, at lower movement frequencies, voluntary and automatic GF control processes operate at different hierarchical levels. Several mechanisms are discussed to account for interaction effects observed at higher movement frequencies.

  2. Superposition of automatic and voluntary aspects of grip force control in humans during object manipulation.

    Directory of Open Access Journals (Sweden)

    Frederic Danion

    Full Text Available When moving grasped objects, people automatically modulate grip force (GF with movement-dependent load force (LF in order to prevent object slip. However, GF can also be modulated voluntarily as when squeezing an object. Here we investigated possible interactions between automatic and voluntary GF control. Participants were asked to generate horizontal cyclic movements (between 0.6 and 2.0 Hz of a hand-held object that was restrained by an elastic band such that the load force (LF reached a peak once per movement cycle, and to simultaneously squeeze the object at each movement reversal (i.e., twice per cycle. Participants also performed two control tasks in which they either only moved (between 0.6 and 2.0 Hz or squeezed (between 1.2 and 4.0 Hz the object. The extent to which GF modulation in the simultaneous task could be predicted from the two control tasks was assessed using power spectral analyses. At all frequencies, the GF power spectra from the simultaneous task exhibited two prominent components that occurred at the cycle frequency (ƒ and at twice this frequency (2ƒ, whereas the spectra from the movement and squeeze control task exhibited only single peaks at ƒ and 2ƒ, respectively. At lower frequencies, the magnitudes of both frequency components in the simultaneous task were similar to the magnitudes of the corresponding components in the control tasks. However, as frequency increased, the magnitudes of both components in the simultaneous task were greater than the magnitudes of the corresponding control task components. Moreover, the phase relationship between the ƒ components of GF and LF began to drift from the value observed in the movement control task. Overall these results suggest that, at lower movement frequencies, voluntary and automatic GF control processes operate at different hierarchical levels. Several mechanisms are discussed to account for interaction effects observed at higher movement frequencies.

  3. Grip force modulation characteristics as a marker for clinical disease progression in individuals with Parkinson disease: case-control study.

    Science.gov (United States)

    Pradhan, Sujata; Scherer, Reinhold; Matsuoka, Yoky; Kelly, Valerie E

    2015-03-01

    Upper extremity deficits are prevalent in individuals with Parkinson disease (PD). In the early stages of PD, such deficits can be subtle and challenging to document on clinical examination. The purpose of this study was to use a novel force sensor system to characterize grip force modulation, including force, temporal, and movement quality parameters, during a fine motor control task in individuals with early stage PD. A case-control study was conducted. Fourteen individuals with early stage PD were compared with a control group of 14 healthy older adults. The relationship of force modulation parameters with motor symptom severity and disease chronicity also was assessed in people with PD. Force was measured during both precision and power grasp tasks using an instrumented twist-cap device capable of rotating in either direction. Compared with the control group, the PD group demonstrated more movement arrests during both precision and power grasp and longer total movement times during the power grasp. These deficits persisted when a concurrent cognitive task was added, with some evidence of force control deficits in the PD group, including lower rates of force production during the precision grasp task and higher peak forces during the power grasp task. For precision grasp, a higher number of movement arrests in single- and dual-task conditions as well as longer total movement times in the dual-task condition were associated with more severe motor symptoms. The sample was small and consisted of individuals in the early stages of PD with mild motor deficits. The group with PD was predominantly male, whereas the control group was predominantly female. The results suggest that assessing grip force modulation deficits during fine motor tasks is possible with instrumented devices, and such sensitive measures may be important for detecting and tracking change early in the progression of PD. © 2015 American Physical Therapy Association.

  4. Performance of repetitive tasks induces decreased grip strength and increased fibrogenic proteins in skeletal muscle: role of force and inflammation.

    Directory of Open Access Journals (Sweden)

    Samir M Abdelmagid

    Full Text Available This study elucidates exposure-response relationships between performance of repetitive tasks, grip strength declines, and fibrogenic-related protein changes in muscles, and their link to inflammation. Specifically, we examined forearm flexor digitorum muscles for changes in connective tissue growth factor (CTGF; a matrix protein associated with fibrosis, collagen type I (Col1; a matrix component, and transforming growth factor beta 1 (TGFB1; an upstream modulator of CTGF and collagen, in rats performing one of two repetitive tasks, with or without anti-inflammatory drugs.To examine the roles of force versus repetition, rats performed either a high repetition negligible force food retrieval task (HRNF, or a high repetition high force handle-pulling task (HRHF, for up to 9 weeks, with results compared to trained only (TR-NF or TR-HF and normal control rats. Grip strength declined with both tasks, with the greatest declines in 9-week HRHF rats. Quantitative PCR (qPCR analyses of HRNF muscles showed increased expression of Col1 in weeks 3-9, and CTGF in weeks 6 and 9. Immunohistochemistry confirmed PCR results, and also showed greater increases of CTGF and collagen matrix in 9-week HRHF rats than 9-week HRNF rats. ELISA, and immunohistochemistry revealed greater increases of TGFB1 in TR-HF and 6-week HRHF, compared to 6-week HRNF rats. To examine the role of inflammation, results from 6-week HRHF rats were compared to rats receiving ibuprofen or anti-TNF-α treatment in HRHF weeks 4-6. Both treatments attenuated HRHF-induced increases in CTGF and fibrosis by 6 weeks of task performance. Ibuprofen attenuated TGFB1 increases and grip strength declines, matching our prior results with anti-TNFα.Performance of highly repetitive tasks was associated with force-dependent declines in grip strength and increased fibrogenic-related proteins in flexor digitorum muscles. These changes were attenuated, at least short-term, by anti-inflammatory treatments.

  5. Measurement of Slip, Force and Deformation Using Hybrid Tactile Sensor System for Robot Hand Gripping an Object

    Directory of Open Access Journals (Sweden)

    Takuya Kawamura

    2013-01-01

    Full Text Available A hybrid tactile sensor system is proposed for a robot hand to hold and grip an object adaptively as the sensor system measures the slip of an object, the gripping force, and the deformation of its silicon rubber sensor element. A hybrid tactile sensor system consists of a Carbon Micro-Coil (CMC touch sensor and a force sensor. The CMC sensor element is made of silicon rubber containing CMCs several micrometres in diameter. It is considered that the sensor element constitutes an LCR circuit, and the CMC touch sensor, deformed mechanically, produces signals due to the modification of the circuit. In this study, a dome-shaped CMC sensor element similar to the shape of a human fingertip was used. This paper first examines the characteristics of the CMC sensor in terms of slip detection when the sensor system held and released an object. Next, the characteristics of the CMC element are clarified with respect to the compression force and deformation when the CMC element was compressed vertically. Finally, methods using the hybrid tactile sensor system are developed to detect the slip of an object and estimate the magnitude of deformation of the CMC element.

  6. Design and Evaluation of a Fiber-Optic Grip Force Sensor with Compliant 3D-Printable Structure for (fMRI Applications

    Directory of Open Access Journals (Sweden)

    Tobias L. Bützer

    2016-01-01

    Full Text Available Grip force sensors compatible with magnetic resonance imaging (MRI are used in human motor control and decision-making research, providing objective and sensitive behavioral outcome measures. Commercial sensors are expensive, cover limited force ranges, rely on pneumatic force transmission that cannot detect fast force changes, or are electrically active, which increases the risk of electromagnetic interference. We present the design and evaluation of a low-cost, 3D-printed, inherently MRI-compatible grip force sensor based on a commercial intensity-based fiber-optic sensor. A compliant monobloc structure with flexible hinges transduces grip force to a linear displacement captured by the fiber-optic sensor. The structure can easily be adapted for different force ranges by changing the hinge thickness. A prototype designed for forces up to 800 N was manufactured and showed a highly linear behavior (nonlinearity of 2.37% and an accuracy of 1.57% in a range between zero and 500 N. It can be printed and assembled within one day and for less than $300. Accurate performance was confirmed, both inside and outside a 3 T MRI scanner within a pilot study. Given its simple design allowing for customization of sensing properties and ergonomics for different applications and requirements, the proposed grip force handle offers researchers a valuable scientific tool.

  7. Combining displacement field and grip force information to determine mechanical properties of planar tissue with complicated geometry.

    Science.gov (United States)

    Nagel, Tina M; Hadi, Mohammad F; Claeson, Amy A; Nuckley, David J; Barocas, Victor H

    2014-11-01

    Performing planar biaxial testing and using nominal stress-strain curves for soft-tissue characterization is most suitable when (1) the test produces homogeneous strain fields, (2) fibers are aligned with the coordinate axes, and (3) strains are measured far from boundaries. Some tissue types [such as lamellae of the annulus fibrosus (AF)] may not allow for these conditions to be met due to their natural geometry and constitution. The objective of this work was to develop and test a method utilizing a surface displacement field, grip force-stretch data, and finite-element (FE) modeling to facilitate analysis of such complex samples. We evaluated the method by regressing a simple structural model to simulated and experimental data. Three different tissues with different characteristics were used: Superficial pectoralis major (SPM) (anisotropic, aligned with axes), facet capsular ligament (FCL) (anisotropic, aligned with axes, bone attached), and a lamella from the AF (anisotropic, aligned off-axis, bone attached). We found that the surface displacement field or the grip force-stretch data information alone is insufficient to determine a unique parameter set. Utilizing both data types provided tight confidence regions (CRs) of the regressed parameters and low parameter sensitivity to initial guess. This combined fitting approach provided robust characterization of tissues with varying fiber orientations and boundaries and is applicable to tissues that are poorly suited to standard biaxial testing. The structural model, a set of C++ finite-element routines, and a Matlab routine to do the fitting based on a set of force/displacement data is provided in the on-line supplementary material.

  8. Grip force and heart rate responses to manual carrying tasks: effects of material, weight, and base area of the container.

    Science.gov (United States)

    Lee, Tzu-Hsien; Tseng, Chia-Yun

    2014-01-01

    This study recruited 16 industrial workers to examine the effects of material, weight, and base area of container on reduction of grip force (ΔGF) and heart rate for a 100-m manual carrying task. This study examined 2 carrying materials (iron and water), 4 carrying weights (4.4, 8.9, 13.3, 17.8 kg), and 2 base areas of container (24 × 24 cm, 35 × 24 cm). This study showed that carrying water significantly increased ΔGF and heart rate as compared with carrying iron. Also, ΔGF and heart rate significantly increased with carrying weight and base area of container. The effects of base area of container on ΔGF and heart rate were greater in carrying water condition than in carrying iron condition. The maximum dynamic effect of water on ΔGF and heart rate occurred when water occupied ~60%-80% of full volume of the container.

  9. Bilateral deficits in fine motor control and pinch grip force are not associated with electrodiagnostic findings in women with carpal tunnel syndrome.

    Science.gov (United States)

    de la Llave-Rincón, Ana Isabel; Fernández-de-Las-Peñas, César; Pérez-de-Heredia-Torres, Marta; Martínez-Perez, Almudena; Valenza, Marie Carmen; Pareja, Juan A

    2011-06-01

    : The aim of this study was to analyze the differences in deficits in fine motor control and pinch grip force between patients with minimal, moderate/mild, or severe carpal tunnel syndrome (CTS) and healthy age- and hand dominance-matched controls. : A case-control study was conducted. The subtests of the Purdue Pegboard Test (one-hand and bilateral pin placements and assemblies) and pinch grip force between the thumb and the remaining four fingers of the hand were bilaterally evaluated in 66 women with minimal (n = 16), moderate (n = 16), or severe (n = 34) CTS and in 20 age- and hand-matched healthy women. The differences among the groups were analyzed using different mixed models of analysis of variance. : A two-way mixed analysis of variance revealed significant differences between groups, not depending on the presence of unilateral or bilateral symptoms (side), for the one-hand pin placement subtest: patients showed bilateral lower scores compared with controls (P < 0.001), without differences among those with minimal, moderate, or severe CTS (P = 0.946). The patients also exhibited lower scores in bilateral pin placement (P < 0.001) and assembly (P < 0.001) subtests, without differences among them. The three-way analysis of variance revealed significant differences among groups (P < 0.001) and fingers (P < 0.001), not depending on the presence of unilateral/bilateral symptoms (P = 0.684), for pinch grip force: patients showed bilateral lower pinch grip force in all fingers compared with healthy controls, without differences among those with minimal, moderate, or severe CTS. : The current study revealed similar bilateral deficits in fine motor control and pinch grip force in patients with minimal, moderate, or severe CTS, supporting that fine motor control deficits are a common feature of CTS not associated with electrodiagnostic findings.

  10. Serotonin and Histamine Therapy Increases Tetanic Forces of Myoblasts, Reduces Muscle Injury, and Improves Grip Strength Performance of Dmdmdx Mice

    Directory of Open Access Journals (Sweden)

    Volkan Gurel

    2015-11-01

    Full Text Available Duchenne muscular dystrophy (DMD is a recessive X-linked fatal disorder caused by a mutation in the dystrophin gene. Although several therapeutic approaches have been studied, none has led to substantial long-term effects in patients. The aim of this study was to test a serotonin and histamine (S&H combination on human skeletal myoblasts and Dmdmdx mice for its effects on muscle strength and injury. Normal human bioartificial muscles (BAMs were treated, and muscle tetanic forces and muscle injury tests were performed using the MyoForce Analysis System. Dmdmdx mice, the murine model of DMD, were administered serotonin, histamine, or S&H combination twice daily for 6 weeks, and functional performance tests were conducted once a week. The S&H combination treatment caused significant increases in tetanic forces at all time points and concentrations tested as compared to the saline controls. Dose response of the BAMs to the treatment demonstrated a significant increase in force generation at all concentrations compared to the controls after 3 to 4 days of drug treatment. The highest 3 concentrations had a significant effect on lowering contractile-induced injury as measured by a reduction in the release of adenylate kinase. Histamine-only and S&H treatments improved grip strength of Dmdmdx mice, whereas serotonin-only treatment resulted in no significant improvement in muscle strength. The results of this study indicate that S&H therapy might be a promising new strategy for muscular dystrophies and that the mechanism should be further investigated.

  11. Fiber-optic Sensor of Tactile Force for Anthropomorphic Robot Grips

    Science.gov (United States)

    Matyunin, SA; Babaev, O. G.

    2018-01-01

    This paper examines an operating principle of a Fiber-Optic Tactile Force Sensor (FOTFS), describes a linearization method and temperature compensation on transfer characteristics (TC) of the FOTFS. The high linearity of the FOTFS TC (the nonlinearity of the TC does not exceed 0.01% within the range of tactile forces from 0 to 1.4 N) and the high temperature stability of the FOTFS (the temperature coefficient does not exceed 0.0025%/°C within the temperature range from 0 to + 50 °C) are experimentally-confirmed.

  12. The relation between force and movement when grasping an object with a precision grip.

    NARCIS (Netherlands)

    Biegstraaten, M.; Smeets, J.B.J.; Brenner, E.

    2006-01-01

    When reaching out for objects, the digits' paths curve so that they approach their positions of contact moving more or less perpendicularly to the local surface orientation. This increases the accuracy of positioning the digits and ensures that any forces exerted at contact are nearly perpendicular

  13. GRIPS bibliography

    Energy Technology Data Exchange (ETDEWEB)

    1978-07-31

    This GRIPS (Geothermal Resources Impact Project Study) contains over 1700 references on a wide variety of subjects dealing directly or indirectly with geothermal development at the Geysers/Calistoga KGRA. (MHR)

  14. [Reliability and validity of the analysis of hand grip and pinch force in isometric and isokinetic conditions].

    Science.gov (United States)

    Benaglia, P G; Franchignoni, F; Ferriero, G; Zebellin, G; Sartorio, F

    1999-01-01

    Strength measurement of the hand grip is at the core of most protocols of functional assessment of the upper limb and in rehabilitation plays a major role in the analysis of treatment efficacy and patients' occupational ability. The aims of this study were to: a) verify the repeatability of strength measurements made during performance of the hand grip and three types of pinch, carried out under isometric and isokinetic conditions; b) compare maximal isometric strength with the corresponding isokinetic value for each of the manoeuvres studied; c) investigate the correlations between the strength expressed in the different manoeuvres, under both isometric and isokinetic conditions. We studied 14 voluntary subjects over three sessions conducted at 48-hr intervals, employing a computerized isokinetic dynamometer Lido WorkSet equipped with device N(o) 21 for the study of pinch (lateral pinch, pulp pinch, chuck pinch) and device N(o) 52 for the grip study. Isometric contractions resulted stronger than isokinetic ones, and the hand grip was found to be the manoeuvre able to produce most strength. The repeatability of each strength measurement test over the three days was high (Intraclass Correlation Coefficients: 0.89-0.93). Correlations between the isometric and isokinetic performance for each of the manoeuvres examined were always high (Pearson's r coefficients: 0.89-0.95) as were those between the different manoeuvres, whether performed in isometric or isokinetic modality (r: 0.60-0.94).

  15. Effects of glovebox gloves on grip and key pinch strength and contact forces for simulated manual operations with three commonly used hand tools.

    Science.gov (United States)

    Sung, Peng-Cheng

    2014-01-01

    This study examined the effects of glovebox gloves for 11 females on maximum grip and key pinch strength and on contact forces generated from simulated tasks of a roller, a pair of tweezers and a crescent wrench. The independent variables were gloves fabricated of butyl, CSM/hypalon and neoprene materials; two glove thicknesses; and layers of gloves worn including single, double and triple gloving. CSM/hypalon and butyl gloves produced greater grip strength than the neoprene gloves. CSM/hypalon gloves also lowered contact forces for roller and wrench tasks. Single gloving and thin gloves improved hand strength performances. However, triple layers lowered contact forces for all tasks. Based on the evaluating results, selection and design recommendations of gloves for three hand tools were provided to minimise the effects on hand strength and optimise protection of the palmar hand in glovebox environments. To improve safety and health in the glovebox environments where gloves usage is a necessity, this study provides recommendations for selection and design of glovebox gloves for three hand tools including a roller, a pair of tweezers and a crescent wrench based on the results discovered in the experiments.

  16. Muscle Fatigue in the Three Heads of the Triceps Brachii During a Controlled Forceful Hand Grip Task with Full Elbow Extension Using Surface Electromyography.

    Science.gov (United States)

    Ali, Asraf; Sundaraj, Kenneth; Badlishah Ahmad, R; Ahamed, Nizam Uddin; Islam, Anamul; Sundaraj, Sebastian

    2015-06-27

    The objective of the present study was to investigate the time to fatigue and compare the fatiguing condition among the three heads of the triceps brachii muscle using surface electromyography during an isometric contraction of a controlled forceful hand grip task with full elbow extension. Eighteen healthy subjects concurrently performed a single 90 s isometric contraction of a controlled forceful hand grip task and full elbow extension. Surface electromyographic signals from the lateral, long and medial heads of the triceps brachii muscle were recorded during the task for each subject. The changes in muscle activity among the three heads of triceps brachii were measured by the root mean square values for every 5 s period throughout the total contraction period. The root mean square values were then analysed to determine the fatiguing condition for the heads of triceps brachii muscle. Muscle fatigue in the long, lateral, and medial heads of the triceps brachii started at 40 s, 50 s, and 65 s during the prolonged contraction, respectively. The highest fatiguing rate was observed in the long head (slope = -2.863), followed by the medial head (slope = -2.412) and the lateral head (slope = -1.877) of the triceps brachii muscle. The results of the present study concurs with previous findings that the three heads of the triceps brachii muscle do not work as a single unit, and the fiber type/composition is different among the three heads.

  17. Muscle Fatigue in the Three Heads of the Triceps Brachii During a Controlled Forceful Hand Grip Task with Full Elbow Extension Using Surface Electromyography

    Directory of Open Access Journals (Sweden)

    Ali Md. Asraf

    2015-06-01

    Full Text Available The objective of the present study was to investigate the time to fatigue and compare the fatiguing condition among the three heads of the triceps brachii muscle using surface electromyography during an isometric contraction of a controlled forceful hand grip task with full elbow extension. Eighteen healthy subjects concurrently performed a single 90 s isometric contraction of a controlled forceful hand grip task and full elbow extension. Surface electromyographic signals from the lateral, long and medial heads of the triceps brachii muscle were recorded during the task for each subject. The changes in muscle activity among the three heads of triceps brachii were measured by the root mean square values for every 5 s period throughout the total contraction period. The root mean square values were then analysed to determine the fatiguing condition for the heads of triceps brachii muscle. Muscle fatigue in the long, lateral, and medial heads of the triceps brachii started at 40 s, 50 s, and 65 s during the prolonged contraction, respectively. The highest fatiguing rate was observed in the long head (slope = −2.863, followed by the medial head (slope = −2.412 and the lateral head (slope = −1.877 of the triceps brachii muscle. The results of the present study concurs with previous findings that the three heads of the triceps brachii muscle do not work as a single unit, and the fiber type/composition is different among the three heads.

  18. Reducing reliance on inaccurate information.

    Science.gov (United States)

    Rapp, David N; Hinze, Scott R; Kohlhepp, Kristine; Ryskin, Rachel A

    2014-01-01

    People learn from the texts that they read, but sometimes what they read is wrong. Previous research has demonstrated that individuals encode even obvious inaccuracies, at times relying on the misinformation to complete postreading tasks. In the present study, we investigated whether the influence of inaccurate information might be reduced by encouraging the retrieval of accurate knowledge. Participants read an extended text that contained both accurate and inaccurate assertions, after which they evaluated the validity of statements associated with those assertions. In general, participants made more mistakes in their evaluations of statements after having read inaccurate as compared to accurate assertions, offering evidence of the influence of misinformation. However, when participants were tasked with correcting inaccuracies during reading, their mistakes were substantially reduced. Encouraging the retrieval of accurate knowledge during reading can reduce the influence of misinformation. These findings are discussed with respect to the contributions of episodic traces and prior knowledge on learning, as well as to the conditions that support successful comprehension.

  19. Observing how others lift light or heavy objects: time-dependent encoding of grip force in the primary motor cortex.

    Science.gov (United States)

    Alaerts, Kaat; de Beukelaar, Toon T; Swinnen, Stephan P; Wenderoth, Nicole

    2012-07-01

    During movement observation, corticomotor excitability of the observer's primary motor cortex (M1) is modulated according to the force requirements of the observed action. Here, we explored the time course of observation-induced force encoding. Force-related changes in M1-excitability were assessed by delivering transcranial magnetic stimulations at distinct temporal phases of an observed reach-grasp-lift action. Temporal changes in force-related electromyographic activity were also assessed during active movement execution. In observation conditions in which a heavy object was lifted, M1-excitability was higher compared to conditions in which a light object was lifted. Both during observation and execution, differential force encoding tended to gradually increase from the grasping phase until the late lift phase. Surprisingly, however, during observation, force encoding was already present at the early reach phase: a time point at which no visual cues on the object's weight were available to the observer. As the observer was aware that the same weight condition was presented repeatedly, this finding may indicate that prior predictions concerning the upcoming weight condition are reflected by M1 excitability. Overall, findings may provide indications that the observer's motor system represents motor predictions as well as muscular requirements to infer the observed movement goal.

  20. Serotonin and Histamine Therapy Increases Tetanic Forces of Myoblasts, Reduces Muscle Injury, and Improves Grip Strength Performance of Dmd(mdx) Mice.

    Science.gov (United States)

    Gurel, Volkan; Lins, Jeremy; Lambert, Kristyn; Lazauski, Joan; Spaulding, James; McMichael, John

    2015-01-01

    Duchenne muscular dystrophy (DMD) is a recessive X-linked fatal disorder caused by a mutation in the dystrophin gene. Although several therapeutic approaches have been studied, none has led to substantial long-term effects in patients. The aim of this study was to test a serotonin and histamine (S&H) combination on human skeletal myoblasts and Dmd(mdx) mice for its effects on muscle strength and injury. Normal human bioartificial muscles (BAMs) were treated, and muscle tetanic forces and muscle injury tests were performed using the MyoForce Analysis System. Dmd(mdx) mice, the murine model of DMD, were administered serotonin, histamine, or S&H combination twice daily for 6 weeks, and functional performance tests were conducted once a week. The S&H combination treatment caused significant increases in tetanic forces at all time points and concentrations tested as compared to the saline controls. Dose response of the BAMs to the treatment demonstrated a significant increase in force generation at all concentrations compared to the controls after 3 to 4 days of drug treatment. The highest 3 concentrations had a significant effect on lowering contractile-induced injury as measured by a reduction in the release of adenylate kinase. Histamine-only and S&H treatments improved grip strength of Dmd(mdx) mice, whereas serotonin-only treatment resulted in no significant improvement in muscle strength. The results of this study indicate that S&H therapy might be a promising new strategy for muscular dystrophies and that the mechanism should be further investigated.

  1. [Diagnostic ability of power measurement of different grip forms for distal median nerve lesion].

    Science.gov (United States)

    Wachter, N; Mentzel, M; Krischak, G; Häderer, C; Gülke, J

    2018-03-01

    Peripheral lesions of the median nerve cause characteristic changes of the grip function of the hand. For evaluating grip force changes, measurement by dynamometers (JAMAR dynamometer and pinch dynamometer) is of high relevance. In this study the ability of grip force measurements of different grip forms was evaluated to discriminate between a simulated median nerve lesion and healthy subjects. In 21 healthy subjects, the grip force of power grip was measured by the JAMAR dynamometer at the second stage including measurement of force at the fingertips and the thenar by a sensor glove. With a pinch dynamometer the power of palmar abduction, precision grip, pincer grip and pinch grip was determined. Measurements were performed with and without median nerve block at the wrist. In power grip of the JAMAR dynamometer at the second stage a significant reduction of the grip force of 13.4% was found (p power distribution between the fingers D2-D5 did not change with median nerve block. The most relevant reduction of grip force in median nerve block compared with the healthy control was measured in palmar abduction (72.1%, p block there was a limited relevance of the measurement of the power grip and force distribution at the fingers by the JAMAR dynamometer. However, the best distinction was observed by dynamometric measurement of other grips than power grip, such as palmar abduction, precision grip, pincer grip and pinch grip. The results could be relevant for the clinical diagnostics and rehabilitation of median nerve lesion, complementing the widespread measurement of the power grip by other grip forms.

  2. Variability of grip kinetics during adult signature writing.

    Directory of Open Access Journals (Sweden)

    Bassma Ghali

    Full Text Available Grip kinetics and their variation are emerging as important considerations in the clinical assessment of handwriting pathologies, fine motor rehabilitation, biometrics, forensics and ergonomic pen design. This study evaluated the intra- and inter-participant variability of grip shape kinetics in adults during signature writing. Twenty (20 adult participants wrote on a digitizing tablet using an instrumented pen that measured the forces exerted on its barrel. Signature samples were collected over 10 days, 3 times a day, to capture temporal variations in grip shape kinetics. A kinetic topography (i.e., grip shape image was derived per signature by time-averaging the measured force at each of 32 locations around the pen barrel. The normalized cross correlations (NCC of grip shape images were calculated within- and between-participants. Several classification algorithms were implemented to gauge the error rate of participant discrimination based on grip shape kinetics. Four different grip shapes emerged and several participants made grip adjustments (change in grip shape or grip height or rotated the pen during writing. Nonetheless, intra-participant variation in grip kinetics was generally much smaller than inter-participant force variations. Using the entire grip shape images as a 32-dimensional input feature vector, a K-nearest neighbor classifier achieved an error rate of 1.2±0.4% in discriminating among participants. These results indicate that writers had unique grip shape kinetics that were repeatable over time but distinct from those of other participants. The topographic analysis of grip kinetics may inform the development of personalized interventions or customizable grips in clinical and industrial applications, respectively.

  3. The influence of the crimp and slope grip position on the finger pulley system.

    Science.gov (United States)

    Schöffl, I; Oppelt, K; Jüngert, J; Schweizer, A; Neuhuber, W; Schöffl, V

    2009-09-18

    In this study the influence of the grip position (crimp grip vs. slope grip position) on the pulley system of the finger was investigated. For this purpose 21 cadaver finger (11 hands, 10 donors) were fixed into an isokinetic loading device. Nine fingers were loaded in the slope grip position and 12 fingers in the crimp grip position. The forces in the flexor tendons and at the fingertip were recorded. A rupture of the A4 pulley occurred most often in the crimp grip position (50%) but did not occur in the slope grip position, in which alternative events were the most common (67%). The forces in the deep flexor tendon (FDP) (slope grip: 371 N, crimp grip: 348 N) and at the fingertip (slope grip: 105 N, crimp grip: 161 N) were not significantly different between the 2 finger positions, but the forces acting on the pulleys were higher in the crimp grip position (A2 pulley: 287 N, A4 pulley: 226 N) than in the slope grip position (A2 pulley: 121 N, A4 pulley: 103 N). The crimp grip position may be the main cause for A4 pulley ruptures but the slope grip position may be hazardous for other injuries as the forces recorded in the flexor tendons and at the fingertip were comparable at the occurrence of a terminal event.

  4. GRIP CLOUD MICROPHYSICS V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GRIP Cloud Microphysics dataset was collected during the GRIP campaign from three probes: the Cloud, Aerosol, and Precipitation Spectrometer (CAPS), the...

  5. Hand-grip isometric strength in judo

    Directory of Open Access Journals (Sweden)

    Juan G Bonitch-Góngora

    2014-02-01

    Full Text Available The grip is an important technical and tactical aspect through which the judokas dominate the adversary, hindering the application of appropriate techniques and favoring their own attack. The judokas must have high levels of isometric force and endurance to this type of force on the gripping muscles of the forearms, as one of the key aspects for success. This article reviews the grip muscular strength and endurance profiles of judokas of different groups (gender, age and competitive level. In general, the peak isometric strength of elite judokas has not changed in the last 40 years and is similar to that reached by non-elite judokas or even registered in large populations. This indicate that the evaluation of the isometric hand grip endurance may be a more relevant parameter than the peak isometric force in judokas, as during the bouts the grip must be maintained for relatively long periods of time and the maximum force cannot be maintained for long. However there are few studies on the ability to resist successive isometric handgrip stress in judokas.

  6. Study on the collision-mechanical properties of tomatoes gripped by ...

    African Journals Online (AJOL)

    The data of collision-mechanical property of tomatoes gripped by robot fingers are important for the gripping control of tomato harvesting robot. In the study, tests of controlling the fingers to grip tomatoes were conducted to ascertain the effects of input current, motor speed and impact positions on the impact force of fingers ...

  7. GRIPS - The Geostationary Remote Infrared Pollution Sounder

    Science.gov (United States)

    Spackman, Ryan; Dickerson, Russell; Schoeberl, Mark; Bloom, Hal; Gordley, Larry; McHugh, Martin; Thompson, Anne; Burrows, John; Zeng, Ning; Marshall, Tom; Fish, Chad; Kim, Jhoon; Park, Rokjin; Warner, Juying; Bhartia, Pawan; Kollonige, Debra

    2013-04-01

    Climate change and air quality are the most pressing environmental issues of the 21st century for America and for the world as a whole. Despite decades of research, the sources and sinks of key greenhouse gases and other pollutants remain highly uncertain making atmospheric composition predictions difficult. The Geostationary Remote Infrared Pollution Sounder (GRIPS) will measure carbon dioxide (CO2), carbon monoxide (CO), and methane (CH4). By using measurements of nitrous oxide (N2O) and the O2 A-band to help correct for clouds and aerosols, GRIPS will achieve unprecedented precision. Together these gases account for about 85% of all climate forcing and they impact atmospheric ozone (O3). GRIPS, employing gas-filter correlation radiometry, uses the target gases themselves in place of dispersive elements to achieve outstanding throughput, sensitivity, and specificity. Because it uses a combination of reflected and thermal IR, GRIPS will detect trace gas concentrations right down to the Earth's surface. When flown in parallel to a UV/VIS sensor such as GEMS on GEO-KOMPSAT-2B over East Asia or the Sentinel 4 on MTG over Europe/Africa, the combination offers powerful finger-printing capabilities to distinguish and quantify diverse pollution sources such as electricity generation, biomass burning, and motor vehicles. From geostationary orbit, GRIPS will be able to focus on important targets to quantify sources, net flux, diurnal cycles, and long-range transport of these key components in the Earth's radiative balance and air quality.

  8. GRIP CAMPAIGN REPORTS V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GRIP Campaign Reports dataset consists of various reports filed by scientists during the GRIP campaign which took place 8/15/2010 - 9/30/2010; however, several...

  9. Long term consistency of handwriting grip kinetics in adults.

    Science.gov (United States)

    Ghali, Bassma; Mamun, Khondaker A; Chau, Tom

    2014-04-01

    While there is growing interest in clinical applications of handwriting grip kinetics, the consistency of these forces over time is not well-understood at present. In this study, we investigated the short- and long-term intra-participant consistency and inter-participant differences in grip kinetics associated with adult signature writing. Grip data were collected from 20 adult participants using a digitizing tablet and an instrumented pen. The first phase of data collection occurred over 10 separate days within a three week period. To ascertain long-term consistency, a second phase of data collection followed, one day per month over several months. In both phases, data were collected three times a day. After pre-processing and feature extraction, nonparametric statistical tests were used to compare the within-participant grip force variation between the two phases. Participant classification based on grip force features was used to determine the relative magnitude of inter-participant versus intra-participant differences. The misclassification rate for the longitudinal data were used as an indication of long term kinetic consistency. Intra-participant analysis revealed significant changes in grip kinetic features between the two phases for many participants. However, the misclassification rate, on average, remained stable, despite different demarcations of training, and testing data. This finding suggests that while signature writing grip forces may evolve over time, inter-participant kinetic differences consistently exceeds within-participant force changes in the long-term. These results bear implications on the collection, modeling and interpretation of grip kinetics in clinical applications.

  10. Computational model of precision grip in Parkinson’s disease: A Utility based approach

    Directory of Open Access Journals (Sweden)

    Ankur eGupta

    2013-12-01

    Full Text Available We propose a computational model of Precision Grip (PG performance in normal subjects and Parkinson’s Disease (PD patients. Prior studies on grip force generation in PD patients show an increase in grip force during ON medication and an increase in the variability of the grip force during OFF medication (Fellows et al 1998; Ingvarsson et al 1997. Changes in grip force generation in dopamine-deficient PD conditions strongly suggest contribution of the Basal Ganglia, a deep brain system having a crucial role in translating dopamine signals to decision making. The present approach is to treat the problem of modeling grip force generation as a problem of action selection, which is one of the key functions of the Basal Ganglia. The model consists of two components: 1 the sensory-motor loop component, and 2 the Basal Ganglia component. The sensory-motor loop component converts a reference position and a reference grip force, into lift force and grip force profiles, respectively. These two forces cooperate in grip-lifting a load. The sensory-motor loop component also includes a plant model that represents the interaction between two fingers involved in PG, and the object to be lifted. The Basal Ganglia component is modeled using Reinforcement Learning with the significant difference that the action selection is performed using utility distribution instead of using purely Value-based distribution, thereby incorporating risk-based decision making. The proposed model is able to account for the precision grip results from normal and PD patients accurately (Fellows et. al. 1998; Ingvarsson et. al. 1997. To our knowledge the model is the first model of precision grip in PD conditions.

  11. GRIP CLOUD MICROPHYSICS V1

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set consists of data collected during the GRIP campaign from three probes: the Cloud, Aerosol, and Precipitation Spectrometer (CAPS), the Precipitation...

  12. Sex difference and relationship among peak grip strength, grip ...

    African Journals Online (AJOL)

    Objective: Hand dominance is a term that describes a preference to use one hand more than the other for everyday tasks. It could be described as the phenomenon that occurs when one hand is preferred to the other for fine motor skills tasks. Hand grip strength is a physiological variable that is affected by a number of ...

  13. Impairments in precision grip correlate with functional measures in adult hemiplegia.

    Science.gov (United States)

    McDonnell, Michelle N; Hillier, Susan L; Ridding, Michael C; Miles, Timothy S

    2006-07-01

    Analysis of a precision grip-lift task provides measures to assess functional disability of the hand, but the correlation between these measures and accepted tests of motor function in stroke patients has not been established. Seventeen subacute stroke patients were studied to compare parameters of a precision grip-lift task between the affected and unaffected side, and to correlate them with function. Functional impairment was assessed with the Action Research Arm Test and the Fugl-Meyer assessment, as well as grip strength and maximal finger-tapping speed. The grip force (GF) and load force (LF) were recorded as patients lifted a custom-built manipulandum. All measures were recorded on two separate occasions, at least 1 week apart. There was good reproducibility between testing sessions for the grip-lift and functional measures. The affected hand gripped the manipulandum for longer prior to lift-off than the unaffected hand, and the normal close temporal coupling between the rate of change of GF and LF during the lift was disrupted. These two measures correlated more highly with the ARAT than the FMA and, when combined with measures of grip strength and tapping speed, explained 71% of the variance of the ARAT. The grip-lift task is a sensitive measure of impaired dexterity following stroke and provides measures which correlate well with a commonly applied functional assessment scale. This task may be used clinically to detect changes in the hemiplegic upper limb during rehabilitation and recovery.

  14. Memory conformity affects inaccurate memories more than accurate memories.

    Science.gov (United States)

    Wright, Daniel B; Villalba, Daniella K

    2012-01-01

    After controlling for initial confidence, inaccurate memories were shown to be more easily distorted than accurate memories. In two experiments groups of participants viewed 50 stimuli and were then presented with these stimuli plus 50 fillers. During this test phase participants reported their confidence that each stimulus was originally shown. This was followed by computer-generated responses from a bogus participant. After being exposed to this response participants again rated the confidence of their memory. The computer-generated responses systematically distorted participants' responses. Memory distortion depended on initial memory confidence, with uncertain memories being more malleable than confident memories. This effect was moderated by whether the participant's memory was initially accurate or inaccurate. Inaccurate memories were more malleable than accurate memories. The data were consistent with a model describing two types of memory (i.e., recollective and non-recollective memories), which differ in how susceptible these memories are to memory distortion.

  15. Reference Values of Grip Strength, Prevalence of Low Grip Strength, and Factors Affecting Grip Strength Values in Chinese Adults.

    Science.gov (United States)

    Yu, Ruby; Ong, Sherlin; Cheung, Osbert; Leung, Jason; Woo, Jean

    2017-06-01

    The objectives of this study were to update the reference values of grip strength, to estimate the prevalence of low grip strength, and to examine the impact of different aspects of measurement protocol on grip strength values in Chinese adults. A cross-sectional survey of Chinese men (n = 714) and women (n = 4014) aged 18-102 years was undertaken in different community settings in Hong Kong. Grip strength was measured with a digital dynamometer (TKK 5401 Grip-D; Takei, Niigata, Japan). Low grip strength was defined as grip strength 2 standard deviations or more below the mean for young adults. The effects of measurement protocol on grip strength values were examined in a subsample of 45 men and women with repeated measures of grip strength taken with a hydraulic dynamometer (Baseline; Fabrication Enterprises Inc, Irvington, NY), using pair t-tests, intraclass correlation coefficient, and Bland and Altman plots. Grip strength was greater among men than among women (P values than the Baseline hydraulic dynamometer (P values were also observed when the measurement was performed with the elbow extended in a standing position, compared with that with the elbow flexed at 90° in a sitting position, using the same dynamometer (P values of grip strength and estimated the prevalence of low grip strength among Chinese adults spanning a wide age range. These findings might be useful for risk estimation and evaluation of interventions. However, grip strength measurements should be interpreted with caution, as grip strength values can be affected by type of dynamometer used, assessment posture, and elbow position. Copyright © 2017 AMDA – The Society for Post-Acute and Long-Term Care Medicine. Published by Elsevier Inc. All rights reserved.

  16. Avoiding inaccurate interpretations when performing ultrasonic tests on welded joints

    International Nuclear Information System (INIS)

    Crostack, H.A.; Schuster, V.

    1992-01-01

    As reported in this article, conventional procedures for assessing errors when performing ultrasonic tests on weldes seams of ten no longer meet modern-day requirements. However, the safety of welded seams can be assessed considerably more accurately by adopting suitable assessment techniques, such as pattern recognition. This will mean that inaccurate interpretations can be ruled out to a large extent. (RHM) [de

  17. Age-associated changes in hand grip and quadriceps muscle strength ratios in healthy adults.

    Science.gov (United States)

    Samuel, Dinesh; Wilson, Keely; Martin, Helen J; Allen, Robert; Sayer, Avan Aihie; Stokes, Maria

    2012-06-01

    Muscle strength may decline with age differentially in the upper and lower limbs. This information is difficult to capture through a single measure. The present study therefore aimed to characterize the relative changes in handgrip and lower limb muscle strength with aging by expressing them as a ratio. Thirty-eight healthy volunteers aged 20-82 years performed maximal voluntary contractions (MVC) of quadriceps and handgrip using a custom-built transducer and a Jamar dynamometer respectively. The grip-quadriceps ratios for young adults was similar in males and females (0.75); indicating knee extensor force exceeded grip force by approximately 25%. Ratios were increased in older adults (p=0.05), and strength of the two muscle groups was approximately equal (1.1). Pearson's correlation coefficients for grip against quadriceps strength were r=0.63 (young males), r=0.83 (young females), r=0.35 (older males) and r=0.05 (older females). The ratio used demonstrated clear differences between the age groups. The reduced muscle strength with increasing age was expected, but the higher grip/quadriceps strength ratios quantify a greater loss of quadriceps than grip strength with aging. It remains to be investigated whether the relatively greater rate of decline in quadriceps strength seen in healthy older people is more exaggerated in those who are frail, which would have implications for using grip strength as a physical marker of lower limb strength and function in those at risk of immobility and falls.

  18. A Practical pedestrian approach to parsimonious regression with inaccurate inputs

    Directory of Open Access Journals (Sweden)

    Seppo Karrila

    2014-04-01

    Full Text Available A measurement result often dictates an interval containing the correct value. Interval data is also created by roundoff, truncation, and binning. We focus on such common interval uncertainty in data. Inaccuracy in model inputs is typically ignored on model fitting. We provide a practical approach for regression with inaccurate data: the mathematics is easy, and the linear programming formulations simple to use even in a spreadsheet. This self-contained elementary presentation introduces interval linear systems and requires only basic knowledge of algebra. Feature selection is automatic; but can be controlled to find only a few most relevant inputs; and joint feature selection is enabled for multiple modeled outputs. With more features than cases, a novel connection to compressed sensing emerges: robustness against interval errors-in-variables implies model parsimony, and the input inaccuracies determine the regularization term. A small numerical example highlights counterintuitive results and a dramatic difference to total least squares.

  19. Endoscopic Localization of Colon Cancer Is Frequently Inaccurate.

    Science.gov (United States)

    Nayor, Jennifer; Rotman, Stephen R; Chan, Walter W; Goldberg, Joel E; Saltzman, John R

    2017-08-01

    Colonoscopic location of a tumor can influence both the surgical procedure choice and overall treatment strategy. To determine the accuracy of colonoscopy in determining the location of colon cancer compared to surgical localization and to elucidate factors that predict discordant colon cancer localization. We conducted a retrospective cross-sectional study of colon cancers diagnosed on colonoscopy at two academic tertiary-care hospitals and two affiliated community hospitals from 2012 to 2014. Colon cancer location was obtained from the endoscopic and surgical pathology reports and characterized by colon segment. We collected data on patient demographics, tumor characteristics, endoscopic procedure characteristics, surgery planned, and surgery performed. Univariate analyses using Chi-squared test and multivariate analysis using forward stepwise logistic regression were performed to determine factors that predict discordant colon cancer localization. There were 110 colon cancer cases identified during the study period. Inaccurate endoscopic colon cancer localization was found in 29% (32/110) of cases. These included 14 cases (12.7%) that were discordant by more than one colonic segment and three cases where the presurgical planned procedure was significantly changed at the time of surgery. On univariate analyses, right-sided colon lesions were associated with increased inaccuracy (43.8 vs 24.4%, p = 0.04). On multivariate analysis, right-sided colon lesions remained independently associated with inaccuracy (OR 1.74, 95% CI 1.03-2.93, p = 0.04). Colon cancer location as determined by colonoscopy is often inaccurate, which can result in intraoperative changes to surgical management, particularly in the right colon.

  20. GRIP HURRICANE IMAGING RADIOMETER (HIRAD) V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GRIP Hurricane Imaging Radiometer (HIRAD) V1 dataset contains measurements of brightness temperature taken at 4, 5, 6 and 6.6 GHz, as well as MERRA 2 m wind...

  1. GRIP LIGHTNING INSTRUMENT PACKAGE (LIP) V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GRIP Lightning Instrument Package (LIP) dataset was collected by the Lightning Instrument Package (LIP), which consists of 6 rotating vane type electric field...

  2. GRIP FLIGHT TRACKS AND ANIMATIONS V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GRIP Flight Tracks and Animations dataset includes both KML files and animation files. The KML files use Google Earth to show the flight tracks on a map. The...

  3. GRIP DC-8 DROPSONDE V3

    Data.gov (United States)

    National Aeronautics and Space Administration — The GRIP DC-8 Dropsonde V3 dataset consists of atmospheric pressure, dry-bulb temperature, dew point temperature, relative humidity, wind direction, wind speed, and...

  4. Força de preensão palmar e pinça digital em diferentes grupos de pilotos da Academia da Força Aérea brasileira Grip and pinch strength among different groups of Brazilian Air Force pilots

    Directory of Open Access Journals (Sweden)

    Gláucia Helena Gonçalves

    2010-06-01

    Full Text Available Pilotos da Academia de Força Aérea (AFA brasileira, durante vôos, realizam movimentos com grande solicitação da musculatura da mão que comanda o manche, o que pode modificar a força muscular. Este estudo teve por objetivo analisar as forças musculares isométricas de preensão palmar e pinças polpa-a-polpa, trípode e lateral de três grupos de pilotos da AFA. Foram avaliados 15 pilotos da Esquadrilha da Fumaça (EDA, 16 instrutores de vôo (PI e 6 pilotos em treinamento (PT, todos do sexo masculino. Para a avaliação, o posicionamento corporal dos pilotos seguiu a padronização da Sociedade Americana de Terapeutas da Mão e a ordem dos movimentos analisados foi predefinida, evitando fadiga muscular. A força muscular isométrica máxima foi coletada em uma contração sustentada por 6 segundos. Os resultados mostram diferenças significativas na preensão, com superioridade das mãos dominantes em relação às não-dominantes em todos os grupos, tendo ainda o grupo EDA obtido valores significativamente superiores em relação aos demais. Nas medidas da pinça trípode, o grupo EDA apresentou significativos valores superiores aos do grupo PT, sendo encontrados valores das mãos dominantes superiores aos das não-dominantes nos grupos EDA e PI. Conclui-se que o treino específico da musculatura da mão durante o vôo, a especificidade e o período de treinamento interferem na força muscular isométrica da mão.Pilots from Brazilian Air Force Academy (AFA perform strentgth- and accuracy-demanding hand movements, which may modify muscle strength. The aim of this study was to analyse hand isometric strength of grip and pulp-to-pulp, tripode and lateral pinch in three groups of male AFA pilots: ADS (Air Demonstration Squadron, n=15; IP (instructor pilots, n=16; and TP (training pilots, n=6. Pilots body positioning during tests followed the standards of the American Society of Hand Therapists; the sequence of assessed movements was

  5. Force

    CERN Document Server

    Graybill, George

    2007-01-01

    Forces are at work all around us. Discover what a force is, and different kinds of forces that work on contact and at a distance. We use simple language and vocabulary to make this invisible world easy for students to ""see"" and understand. Examine how forces ""add up"" to create the total force on an object, and reinforce concepts and extend learning with sample problems.

  6. Entanglement-fidelity relations for inaccurate ancilla-driven quantum computation

    International Nuclear Information System (INIS)

    Morimae, Tomoyuki; Kahn, Jonas

    2010-01-01

    It was shown by T. Morimae [Phys. Rev. A 81, 060307(R) (2010)] that the gate fidelity of an inaccurate one-way quantum computation is upper bounded by a decreasing function of the amount of entanglement in the register. This means that a strong entanglement causes the low gate fidelity in the one-way quantum computation with inaccurate measurements. In this paper, we derive similar entanglement-fidelity relations for the inaccurate ancilla-driven quantum computation. These relations again imply that a strong entanglement in the register causes the low gate fidelity in the ancilla-driven quantum computation if the measurements on the ancilla are inaccurate.

  7. On automatic determination of movement phases in manual transport during the precision grip.

    Science.gov (United States)

    Hosseini, N; Hejdukova, B; Ingvarsson, P E; Johnels, B; Olsson, T

    2000-01-01

    Integrated movement and force analysis of the precision grip-lift sequence (grasping an object between index finger and thumb) is a useful tool in studies on manipulative hand functions. The everyday Manual Transport tasks, moving objects from one place to another, exhibits powerful test possibilities because it includes the precision grip. In this study, as a step towards the exploitation of these possibilities, we created an algorithm that extracts sequence of phases in this task. The mathematical and dynamical properties of the movement and force signals were used to determine the start and the end of each phase. The grip-lift synergy was quantified by the correlation coefficient during each phase. Eight patients with Parkinson's Disease (PD) and 10 healthy persons were studied. The PD patients were tested both in the medicated (ON) and the unmedicated (OFF) state. The object was lifted with the index finger and the thumb, moved a short distance, and put down on a shelf. The preliminary results of these experiments displayed significantly higher coordination between the grip and load forces in the initial phases, before the lift was completely established, than during the transport phases. This was evident both in PD patients and healthy subjects. This method provides an automatic analysis of the motor performance during an arm-hand movement that is important in daily life to aid in clinical diagnosis.

  8. GRIP METEOSAT SECOND GENERATION (MSG) IMAGE DATA V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GRIP Meteosat Second Generation (MSG) data and browse was collected during the Genesis and Rapid Intensification Processes (GRIP) experiment from 15 Aug 2010 to...

  9. GRIP WB-57 NAVIGATION AND HOUSEKEEPING DATA V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GRIP WB-57 Navigation data was collected on flight days occuring between July 13 , 2010 to September 17, 2010 during the GRIP field campaign. The NASA WB-57 is a...

  10. GRIP DC-8 NAVIGATION AND HOUSEKEEPING DATA V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GRIP DC-8 Navigation and Housekeeping Data contains aircraft navigational data obtained during the GRIP campaign (15 Aug 2010 - 30 Sep 2010). The major goal was...

  11. GRIP GLOBAL HAWK NAVIGATION AND HOUSEKEEPING DATA V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GRIP Global Hawk Navigation data was collected during the period Aug 15, 2010 to September 24, 2010 during the GRIP field campaign. The Global Hawk is an...

  12. GRIP METEOSAT SECOND GENERATION (MSG) IMAGE DATA V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GRIP Meteosat Second Generation (MSG) Image Data was collected during the Genesis and Rapid Intensification Processes (GRIP) experiment from August 15, 2010 to...

  13. The GRIP method for collaborative roadmapping workshops

    DEFF Research Database (Denmark)

    Piirainen, Kalle

    2015-01-01

    Technology roadmapping is a well-known tool for technology management, but practical advice for facilitating collaborative roadmapping workshops is relatively scarce. To cater for this need, we have designed a method for collaborative roadmapping, dubbed the GRIP method, for facilitating group work...

  14. Improved Friction Joint With Self-Locking Grips

    DEFF Research Database (Denmark)

    Costache, Andrei; Glejbøl, Kristian; Sivebæk, Ion Marius

    2016-01-01

    to develop asuperior dry friction grip. Experimental results are carried using a dedicated test setup, through which the test parameters can be accurately controlled. The efficiency of the grip system during pullout is superior to results obtained with flat grips. Numerical results offer an in......-depth understanding of the influence between friction, geometrical parameters,and performance, making it possible to optimize the design. Results show that this grip system offers immediate technical applications, in a variety of conditions....

  15. G×E Interaction Influences Trajectories of Hand Grip Strength

    DEFF Research Database (Denmark)

    Petersen, Inge; Pedersen, Nancy L; Rantanen, Taina

    2016-01-01

    Age-related decline in grip strength predicts later life disability, frailty, lower well-being and cognitive change. While grip strength is heritable, genetic influence on change in grip strength has been relatively ignored, with non-shared environmental influence identified as the primary contri...

  16. Precision grip in congenital and acquired hemiparesis: similarities in impairments and implications for neurorehabilitation - review

    Directory of Open Access Journals (Sweden)

    Yannick eBleyenheuft

    2014-06-01

    Full Text Available Background: Patients with congenital and acquired hemiparesis incur long-term functional deficits, among which the loss of prehension that may impact their functional independence. Identifying, understanding and comparing the underlying mechanisms of prehension impairments represent an opportunity to better adapt neurorehabilitationObjective: The present review aims to provide a better understanding of precision grip deficits in congenital and acquired hemiparesis and to determine whether the severity and type of fine motor control impairments depend on whether or not the lesions are congenital or acquired in adulthood. Methods: Using combinations of the following key words: fingertip force, grip force, precision grip, cerebral palsy, stroke, pubmed and Scopus databases were used to search studies from 1984 to 2013. Results: Individuals with both congenital and acquired hemiparesis were able to some extent to use anticipatory motor control in precision grip tasks, even if this control was impaired in the paretic hand. In both congenital or acquired hemiparesis, the ability to plan efficient anticipatory motor control when the less-affected hand is used provides a possibility to remediate impairments in anticipatory motor control of the paretic hand. Conclusion: Surprisingly we observed very few differences between the results of studies in children with congenital hemiplegia and stroke patients. We suggest that the underlying specific strategies of neurorehabilitation developed for each one could benefit the other.

  17. Maximal intermittent handgrip strategy: design and evaluation of an exercise protocol and a grip tool.

    Science.gov (United States)

    Bentley, Danielle Christine; Thomas, Scott Gordon

    2016-01-01

    Handgrip (HG) exercise has been prescribed as a lifestyle intervention to successfully reduce resting blood pressure (BP) among heterogeneous groups of participants. Current HG protocols have limited accessibility due to complicated exercise prescriptions and sophisticated required equipment. Therefore, this research describes the design and evaluation of the maximal intermittent (MINT) HG exercise strategy, consisting of both a novel exercise protocol (32×5 seconds maximal grip squeezes separated by 5 seconds of rest between sets) and an original grip tool. This research was a multistep progressive design that included 51 postmenopausal women as participants in three separate research studies. Part 1 of this research focuses on the MINT exercise protocol. A literature-informed rationale for the design of the protocol is described. This includes exercise intensity, work-to-rest ratio, and total exercise duration with reference to the unique physiology (mechanoreflex and metaboreflex) of postmenopausal women. Subsequent experimental analyses of acute responses to the MINT protocol revealed that women produced 50% of their maximum grip force with moderate cardiovascular responses (increases of systolic BP: 41.6 mmHg, diastolic BP: 20.1 mmHg, heart rate: 35.1 bpm) that remained far below the thresholds of concern identified by the American College of Sports Medicine. Part 2 of this research describes the creation of a novel grip tool, beginning with a mixed-methods assessment of participant opinions regarding two distinct in-laboratory grip tools, leading to the creation of four prototype MINT tools. Structured focus groups revealed a strong preference for MINT prototype 1 for all tool design features, including color, shape, size, and foam grip. Collectively, the result of this multistep research is a novel HG exercise strategy with enhanced accessibility by being easy to understand and simple to execute. The long-term training effectiveness of MINT as an exercise

  18. Distinguishing highly confident accurate and inaccurate memory: insights about relevant and irrelevant influences on memory confidence

    Science.gov (United States)

    Chua, Elizabeth F.; Hannula, Deborah E.; Ranganath, Charan

    2012-01-01

    It is generally believed that accuracy and confidence in one’s memory are related, but there are many instances when they diverge. Accordingly, it is important to disentangle the factors which contribute to memory accuracy and confidence, especially those factors that contribute to confidence, but not accuracy. We used eye movements to separately measure fluent cue processing, the target recognition experience, and relative evidence assessment on recognition confidence and accuracy. Eye movements were monitored during a face-scene associative recognition task, in which participants first saw a scene cue, followed by a forced-choice recognition test for the associated face, with confidence ratings. Eye movement indices of the target recognition experience were largely indicative of accuracy, and showed a relationship to confidence for accurate decisions. In contrast, eye movements during the scene cue raised the possibility that more fluent cue processing was related to higher confidence for both accurate and inaccurate recognition decisions. In a second experiment, we manipulated cue familiarity, and therefore cue fluency. Participants showed higher confidence for cue-target associations for when the cue was more familiar, especially for incorrect responses. These results suggest that over-reliance on cue familiarity and under-reliance on the target recognition experience may lead to erroneous confidence. PMID:22171810

  19. The laboratory station for tyres grip testing on different surfaces

    Science.gov (United States)

    Kalinowski, K.; Grabowik, C.; Janik, W.; Ćwikła, G.; Skowera, M.

    2015-11-01

    The paper presents the conception of the device for tyre grip testing in the laboratory conditions. The main purpose is to provide a device working in confined spaces, which enables rapid changes of the tested samples of the road surfaces. Among the key assumptions the minimization of the device dimensions and the relative ease of transportation and mobility - the ability to quick assemble and disassemble were also assumed. The main components of the projected workstation includes: the replaceable platform for mounting samples of a road surface, the roller conveyor, the drive of the platform, the wheel mounting assembly and the axial force measuring system. At the design the station a morphological structure method has been used, particular elements have been optimized individually.

  20. The Optimal Design for Grip Force of Material Handling

    OpenAIRE

    V. Tawiwat; S. Sarawut

    2008-01-01

    Applied a mouse-s roller with a gripper to increase the efficiency for a gripper can learn to a material handling without slipping. To apply a gripper, we use the optimize principle to develop material handling by use a signal for checking a roller mouse that rotate or not. In case of the roller rotates means that the material slips. A gripper will slide to material handling until the roller will not rotate. As this experiment has test material handling for comparing a gr...

  1. Association between inaccurate estimation of body size and obesity in schoolchildren.

    Science.gov (United States)

    Costa, Larissa da Cunha Feio; Silva, Diego Augusto Santos; Almeida, Sebastião de Sousa; de Vasconcelos, Francisco de Assis Guedes

    2015-01-01

    To investigate the prevalence of inaccurate estimation of own body size among Brazilian schoolchildren of both sexes aged 7-10 years, and to test whether overweight/obesity; excess body fat and central obesity are associated with inaccuracy. Accuracy of body size estimation was assessed using the Figure Rating Scale for Brazilian Children. Multinomial logistic regression was used to analyze associations. The overall prevalence of inaccurate body size estimation was 76%, with 34% of the children underestimating their body size and 42% overestimating their body size. Obesity measured by body mass index was associated with underestimation of body size in both sexes, while central obesity was only associated with overestimation of body size among girls. The results of this study suggest there is a high prevalence of inaccurate body size estimation and that inaccurate estimation is associated with obesity. Accurate estimation of own body size is important among obese schoolchildren because it may be the first step towards adopting healthy lifestyle behaviors.

  2. Effect of cervical spine manipulative therapy on judo athletes' grip strength.

    Science.gov (United States)

    Botelho, Marcelo B; Andrade, Bruno B

    2012-01-01

    The objective of this study was to perform an investigation evaluating if cervical spinal manipulative therapy (SMT) can increase grip strength on judo athletes in a top 10 national-ranked team. A single-blinded, prospective, comparative, pilot, randomized, clinical trial was performed with 18 athletes of both sexes from a judo team currently competing on a national level. The athletes were randomly assigned to 2 groups: chiropractic SMT and sham. Three interventions were performed on each of the athletes at different time points. Force measurements were obtained by a hydraulic dynamometer immediately before and after each intervention at the same period before training up to 3 weeks with at least 36 hours between interventions. Analysis of grip strength data revealed a statistically significant increase in strength within the treatment group after the first intervention (6.95% right, 12.61% left) as compared with the second (11.53% right, 17.02% left) and the third interventions (10.53% right, 16.81% left). No statistically significant differences were found in grip strength comparison within the sham group. Overall differences in strength were consistently significant between the study groups (P = .0025). The present study suggests that the grip strength of national level judo athletes receiving chiropractic SMT improved compared to those receiving sham. Copyright © 2012 National University of Health Sciences. Published by Mosby, Inc. All rights reserved.

  3. Functional relationship between dominant and non-dominant hand in motor task - hand grip strength endurance

    Directory of Open Access Journals (Sweden)

    Kljajić Dragana

    2012-01-01

    Full Text Available The aim of this study was to determine the functional relationship between dominant and non-dominant hand in the strength endurance motor task - hand grip, in the referent population of healthy and young persons. For the purpose of the research we have implemented the method of isometric dynamometry and standardized hand grip test. The study included 48 participants, 23 of them being of female and 25 of male gender. The analysis of variance (ANOVA was used to determine the difference between the sets of variables in the function of gender and functional dimorphism, while the Bonferroni criterion was applied to determine the differences between pairs of individual variables. The difference between the maximum hand grip of dominant and non-dominant hand in female participants amounted to 9.28%, and in male ones 7.39% in favor of the dominant hand. There is no statistically significant difference between nondominant and dominant hand regarding the force endurance time aspect at 30%, 50% and 80% out of the maximum hand grip level, as well as at the absolute and relative force impulse indicators as an endurance measure. The value of gender dimorphism in relation to the absolute indicators of force momentum at 30%, 50% and 80% out of the maximum hand grip level in female participants is 0.9714, 0.9145, 0.9301, and in male participants 0.9515, 0.8264 and 0.8606. The force momentum indicators value at 30%, 50% and 80% out of the maximum hand grip level in female participants is ImpF30%=21167.58±6923.67 Ns, ImpF50%=10846.94±3800.56 Ns and ImpF80%=5438.46±1993.12 Ns, and in male participants ImpF30%=17734.03±6881.92 Ns, ImpF50%=13903.61±3437.76 Ns and ImpF80%=5117.53±1894.78 Ns. The obtained results can be used as the criteria for further research in special education and rehabilitation, medical and professional rehabilitation.

  4. GRIP LIDAR ATMOSPHERIC SENSING EXPERIMENT (LASE) V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GRIP Lidar Atmospheric Sensing Experiment (LASE) dataset was collected by NASA's Lidar Atmospheric Sensing Experiment (LASE) system, which is an airborne...

  5. GRIP LANGLEY AEROSOL RESEARCH GROUP EXPERIMENT (LARGE) V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GRIP Langley Aerosol Research Group Experiment (LARGE) dataset was collected by the Langley Aerosol Research Group Experiment (LARGE), which measures ultrafine...

  6. Precision grip responses to unexpected rotational perturbations scale with axis of rotation.

    Science.gov (United States)

    De Gregorio, Michael; Santos, Veronica J

    2013-04-05

    It has been established that rapid, pulse-like increases in precision grip forces ("catch-up responses") are elicited by unexpected translational perturbations and that response latency and strength scale according to the direction of linear slip relative to the hand as well as gravity. To determine if catch-up responses are elicited by unexpected rotational perturbations and are strength-, axis-, and/or direction-dependent, we imposed step torque loads about each of two axes which were defined relative to the subject's hand: the distal-proximal axis away from and towards the subject's palm, and the grip axis which connects the two fingertips. Precision grip responses were dominated initially by passive mechanics and then by active, unimodal catch-up responses. First dorsal interosseous activity, marking the start of the catch-up response, began 71-89 ms after the onset of perturbation. The onset latency, shape, and duration (217-231 ms) of the catch-up response were not affected by the axis, direction, or magnitude of the rotational perturbation, while strength was scaled by axis of rotation and slip conditions. Rotations about the grip axis that tilted the object away from the palm and induced rotational slip elicited stronger catch-up responses than rotations about the distal-proximal axis that twisted the object between the digits. To our knowledge, this study is the first to investigate grip responses to unexpected torque loads and to show characteristic, yet axis-dependent, catch-up responses for conditions other than pure linear slip. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Grip-dependent cortico-spinal excitability during grasping imagination and execution.

    Science.gov (United States)

    Cesari, Paola; Pizzolato, Fabio; Fiorio, Mirta

    2011-06-01

    Studies converge in indicating a substantial similarity of the rules and mechanisms underlying execution, observation and imagery of actions, along with a large overlapping of their neural substrates. Recent transcranial magnetic stimulation (TMS) studies have demonstrated a muscle-specific facilitation of the observer's motor system for force requirement and type of grip during grasping observation. However, whether similar fine-tuned muscle-specificity occurs even during imagination, when subjects are free to select the most convenient grip configuration, is still unknown. Here we applied TMS over the primary motor cortex and measured the corticospinal excitability (MEP) in three muscles (FDI, ADM and FDS) while subjects imagined grasping spheres of different dimensions and materials. This range of object weights and sizes (diameters) allowed subjects to freely imagine the most suitable grip configuration among several possibilities. Activation measured during grasping imagination has been also compared to that obtained during real execution (EMG recorded from the same muscles). We found that during imagination of grasping small objects, the FDI muscle was more active than the ADM and the FDS, whereas the opposite pattern was found for big objects. Imagination of medium size objects, instead, required an equal involvement of the three muscles. The same pattern was observed when subjects were asked to perform the action. This suggests that during imagination, the cortico-spinal system is modulated in a muscle-specific/grip-specific way, as if the action would be really performed. However, when force was required (i.e., for the aluminum objects), the motor activation obtained during action execution was more fine-tuned to object dimensions than the facilitation recorded during imagination, suggesting a separate control of force production. Copyright © 2011 Elsevier Ltd. All rights reserved.

  8. The Effects of Industrial Protective Gloves and Hand Skin Temperatures on Hand Grip Strength and Discomfort Rating.

    Science.gov (United States)

    Ramadan, Mohamed Z

    2017-12-04

    Daily working activities and functions require a high contribution of hand and forearm muscles in executing grip force. To study the effects of wearing different gloves on grip strength, under a variety of hand skin temperatures, an assessment of the maximum grip strength was performed with 32 healthy male workers with a mean age (standard deviation) of 30.44 (5.35) years wearing five industrial gloves at three hand skin temperatures. Their ages and anthropometric characteristics including body mass index (BMI), hand length, hand width, hand depth, hand palm, and wrist circumference were measured. The hand was exposed to different bath temperatures (5 °C, 25 °C, and 45 °C) and hand grip strength was measured using a Jamar hydraulic hand dynamometer with and without wearing the gloves (chemical protection glove, rubber insulating glove, anti-vibration impact glove, cotton yarn knitted glove, and RY-WG002 working glove). The data were analyzed using the Shapiro-Wilk test, Pearson correlation coefficient, Tukey test, and analysis of variance (ANOVA) of the within-subject design analysis. The results showed that wearing gloves significantly affected the maximum grip strength. Wearing the RY-WG002 working glove produced a greater reduction on the maximum grip when compared with the bare hand, while low temperatures (5 °C) had a significant influence on grip when compared to medium (25 °C) and high (45 °C) hand skin temperatures. In addition, participants felt more discomfort in both environmental extreme conditions. Furthermore, they reported more discomfort while wearing neoprene, rubber, and RY-WG002 working gloves.

  9. Precision grip control while walking down a step in children with unilateral cerebral palsy.

    Directory of Open Access Journals (Sweden)

    Daniela Ebner-Karestinos

    Full Text Available To compare grip force (GF and load force (LF coordination while walking down a step between children with unilateral cerebral palsy (UCP and typically developing (TD children.Twenty-five children with UCP (age 9.3±1.7 y and 25 TD controls (age 9.4±2.1 y walked down a step while holding a grip-lift manipulandum. Dynamic and temporal variables were analyzed. The maximum voluntary contraction (MVC was also assessed.The temporal course was perturbed mainly in the more affected hand of children with UCP when compared to TD children because the increases in GF and LF onset occurred in a reversed order. Compared with the TD controls, the children with UCP presented higher LF values on both hands and a higher GF on the less affected hand. In children with UCP, the GF to LF adaptation was adequate on the less affected hand but overestimated on the more affected hand. Furthermore, children with UCP presented a lower MVC in the more affected hand, leading to a higher percentage of MVC used during the task.Our findings highlight an anticipatory control of precision grip during a stepping down task in children with UCP that is adequate for the less affected hand but altered for the more affected hand.

  10. Normal values for hand grip strength in healthy Nigerian adults ...

    African Journals Online (AJOL)

    Background: Assessment of hand grip strength is used in a wide range of clinical settings particularly during management of hand injuries and diseases affecting hand function. This study aimed to determine age and gender specific normal values of hand grip strength in healthy adults in Nigeria and compare values ...

  11. Algorithm Design for Grip-Pattern Verification in Smart Gun

    NARCIS (Netherlands)

    Shang, X.; Veldhuis, Raymond N.J.; Bazen, A.M.; Ganzevoort, W.P.T.

    2005-01-01

    The Secure Grip project1 focuses on the development of a hand-grip pattern recognition system, as part of the smart gun. Its target customer is the police. To explore the authentication performance of this system, we collected data from a group of police officers, and made authentication simulations

  12. Grip-pattern recognition: Applied to a smart gun

    NARCIS (Netherlands)

    Shang, X.

    2008-01-01

    In our work the verification performance of a biometric recognition system based on grip patterns, as part of a smart gun for use by the police ocers, has been investigated. The biometric features are extracted from a two-dimensional pattern of the pressure, exerted on the grip of a gun by the hand

  13. Preserved grip selection planning in chronic unilateral upper extremity amputees

    Science.gov (United States)

    Frey, Scott H.

    2016-01-01

    Upper limb amputees receive no proprioceptive or visual sensory feedback about their absent hand. In this study, we asked whether chronic amputees nevertheless retain the ability to accurately plan gripping movements. Fourteen patients and matched controls performed two grip selection tasks: overt grip selection (OGS), in which they used their intact hand to grasp an object that appeared in different orientations using the most natural (under- or overhand) precision grip, and prospective grip selection (PGS), in which they selected the most natural grip for either hand without moving. We evaluated planning accuracy by comparing concordance between grip preferences expressed in PGS vs. OGS for the intact hand and PGS vs. the inverse of OGS responses for the affected hand. Overall, amputees showed no deficits in the accuracy of grip selection planning based on either hand and a consistent preference for less awkward hand postures. We found no evidence for a speed-accuracy tradeoff. Furthermore, selection accuracy did not depend on phantom mobility, phantom limb pain, time since amputation, or the residual limb’s shoulder posture. Our findings demonstrate that unilateral upper limb amputees retain the ability to plan movements based on the biomechanics of their affected hand even many years after limb loss. This unimpaired representation may stem from persistent higher-level activity-independent internal representations or may be sustained by sensory feedback from the intact hand. PMID:21863261

  14. Biometric verification based on grip-pattern recognition

    NARCIS (Netherlands)

    Veldhuis, Raymond N.J.; Bazen, A.M.; Kauffman, J.A.; Hartel, Pieter H.; Delp, Edward J.; Wong, Ping W.

    This paper describes the design, implementation and evaluation of a user-verification system for a smart gun, which is based on grip-pattern recognition. An existing pressure sensor consisting of an array of 44 x 44 piezoresistive elements is used to measure the grip pattern. An interface has been

  15. The Activities of the Muscles around the Ankle Joint during Foot-gripping are Affected by the Angle of the Ankle.

    Science.gov (United States)

    Soma, Masayuki; Murata, Shin; Kai, Yoshihiro; Nakae, Hideyuki; Satou, Yosuke

    2013-12-01

    [Purpose] The purpose of this study was to determine the activities of the muscles around the ankle joint during foot gripping. [Subjects] The subjects of this study were 17 healthy females. [Methods] We measured the maximum voluntary contraction (MVC) activities of the soleus muscle, the medial head of the gastrocnemius muscle, and the tibialis anterior muscle, and calculated %IEMG during foot gripping in 3 different ankle joint positions: 10° of plantar flexion, 0°, and 10° of dorsiflexion. [Results] The maximal force of foot gripping achived by the crural muscles in any ankle position was 30-50% IMEG of the MVC. Repeated analysis of variance showed that the %IEMG was significantly lower in 10°of dorsiflexion than in the other 2 positions for all muscles. [Conclusion] These results suggested that the crural muscles help the ankle joint by co-contracting during foot gripping.

  16. Accurate and inaccurate HIV transmission beliefs, stigmatizing and HIV protection motivation in northern Thailand

    NARCIS (Netherlands)

    Boer, H.; Emons, P.A.A.

    2004-01-01

    We assessed the relation between accurate beliefs about HIV transmission and inaccurate beliefs about HIV transmission and emotional reactions to people with AIDS (PWA) and AIDS risk groups, stigmatizing attitudes and motivation to protect from HIV. In Chiang Rai, northern Thailand, 219 respondents

  17. A non-convex variational approach to photometric stereo under inaccurate lighting

    DEFF Research Database (Denmark)

    Quéau, Yvain; Wu, Tao; Lauze, Francois Bernard

    2017-01-01

    This paper tackles the photometric stereo problem in the presence of inaccurate lighting, obtained either by calibration or by an uncalibrated photometric stereo method. Based on a precise modeling of noise and outliers, a robust variational approach is introduced. It explicitly accounts for self...

  18. Leg mass characteristics of accurate and inaccurate kickers--an Australian football perspective.

    Science.gov (United States)

    Hart, Nicolas H; Nimphius, Sophia; Cochrane, Jodie L; Newton, Robert U

    2013-01-01

    Athletic profiling provides valuable information to sport scientists, assisting in the optimal design of strength and conditioning programmes. Understanding the influence these physical characteristics may have on the generation of kicking accuracy is advantageous. The aim of this study was to profile and compare the lower limb mass characteristics of accurate and inaccurate Australian footballers. Thirty-one players were recruited from the Western Australian Football League to perform ten drop punt kicks over 20 metres to a player target. Players were separated into accurate (n = 15) and inaccurate (n = 16) groups, with leg mass characteristics assessed using whole body dual energy x-ray absorptiometry (DXA) scans. Accurate kickers demonstrated significantly greater relative lean mass (P ≤ 0.004) and significantly lower relative fat mass (P ≤ 0.024) across all segments of the kicking and support limbs, while also exhibiting significantly higher intra-limb lean-to-fat mass ratios for all segments across both limbs (P ≤ 0.009). Inaccurate kickers also produced significantly larger asymmetries between limbs than accurate kickers (P ≤ 0.028), showing considerably lower lean mass in their support leg. These results illustrate a difference in leg mass characteristics between accurate and inaccurate kickers, highlighting the potential influence these may have on technical proficiency of the drop punt.

  19. Protein loop modeling using a new hybrid energy function and its application to modeling in inaccurate structural environments.

    Directory of Open Access Journals (Sweden)

    Hahnbeom Park

    Full Text Available Protein loop modeling is a tool for predicting protein local structures of particular interest, providing opportunities for applications involving protein structure prediction and de novo protein design. Until recently, the majority of loop modeling methods have been developed and tested by reconstructing loops in frameworks of experimentally resolved structures. In many practical applications, however, the protein loops to be modeled are located in inaccurate structural environments. These include loops in model structures, low-resolution experimental structures, or experimental structures of different functional forms. Accordingly, discrepancies in the accuracy of the structural environment assumed in development of the method and that in practical applications present additional challenges to modern loop modeling methods. This study demonstrates a new strategy for employing a hybrid energy function combining physics-based and knowledge-based components to help tackle this challenge. The hybrid energy function is designed to combine the strengths of each energy component, simultaneously maintaining accurate loop structure prediction in a high-resolution framework structure and tolerating minor environmental errors in low-resolution structures. A loop modeling method based on global optimization of this new energy function is tested on loop targets situated in different levels of environmental errors, ranging from experimental structures to structures perturbed in backbone as well as side chains and template-based model structures. The new method performs comparably to force field-based approaches in loop reconstruction in crystal structures and better in loop prediction in inaccurate framework structures. This result suggests that higher-accuracy predictions would be possible for a broader range of applications. The web server for this method is available at http://galaxy.seoklab.org/loop with the PS2 option for the scoring function.

  20. Inaccurate Citations in Biomedical Journalism: Effect on the Impact Factor of the American Journal of Roentgenology.

    Science.gov (United States)

    Karabulut, Nevzat

    2017-03-01

    The aim of this study is to investigate the frequency of incorrect citations and its effects on the impact factor of a specific biomedical journal: the American Journal of Roentgenology. The Cited Reference Search function of Thomson Reuters' Web of Science database (formerly the Institute for Scientific Information's Web of Knowledge database) was used to identify erroneous citations. This was done by entering the journal name into the Cited Work field and entering "2011-2012" into the Cited Year(s) field. The errors in any part of the inaccurately cited references (e.g., author names, title, year, volume, issue, and page numbers) were recorded, and the types of errors (i.e., absent, deficient, or mistyped) were analyzed. Erroneous citations were corrected using the Suggest a Correction function of the Web of Science database. The effect of inaccurate citations on the impact factor of the AJR was calculated. Overall, 183 of 1055 citable articles published in 2011-2012 were inaccurately cited 423 times (mean [± SD], 2.31 ± 4.67 times; range, 1-44 times). Of these 183 articles, 110 (60.1%) were web-only articles and 44 (24.0%) were print articles. The most commonly identified errors were page number errors (44.8%) and misspelling of an author's name (20.2%). Incorrect citations adversely affected the impact factor of the AJR by 0.065 in 2012 and by 0.123 in 2013. Inaccurate citations are not infrequent in biomedical journals, yet they can be detected and corrected using the Web of Science database. Although the accuracy of references is primarily the responsibility of authors, the journal editorial office should also define a periodic inaccurate citation check task and correct erroneous citations to reclaim unnecessarily lost credit.

  1. Early Active Rehabilitation After Grip Reconstructive Surgery in Tetraplegia.

    Science.gov (United States)

    Wangdell, Johanna; Bunketorp-Käll, Lina; Koch-Borner, Sabrina; Fridén, Jan

    2016-06-01

    To describe and evaluate the concept of early active rehabilitation after tendon transfer to restore grip function in tetraplegia. Retrospective cohort study. Two nonprofit rehabilitation units in Sweden and Switzerland. All patients with tetraplegia who underwent tendon transfer to restore grip ability during 2009 to 2013 (N=49). Reconstructive tendon transfer surgery with early active rehabilitation to restore grip ability in tetraplegia. Grip and pinch strength, grip ability test, and outcome of prioritized activities. In the 49 surgeries performed, postoperative complications included 2 patients with bleeding and 2 infections related to the surgery. There were no reported ruptures or lengthening of transferred tendons. Within 24 hours after surgery, all 47 patients (100%) with finger flexion reconstruction succeeded to activate their finger flexion. All but 1 patient with reconstructed thumb flexion sucessfully activated their thumb flexion (n=40). Three weeks after surgery, all patients (100%) were able to perform basic activities of daily living, and instrumental activities of daily living were achieved by 74%. One year after surgery, the maximum grip strength in restored finger flexion was on average 6.9kg (range, 1.5-15kg; n=29). The maximum pinch strength in restored thumb flexion was on average 3.7kg (range, 1-20; n=29). On average, grip ability improved from 33 to 101 (n=19) according to the COPM. Prioritized activity limitations, as measured with the COPM, equated to an average of 3.5 steps (2.5 steps preoperatively to 6 steps postoperatively). Patients' perceived satisfaction with this improvement was 4 steps (increasing from 2 steps preoperatively to 6 steps postoperatively). Grip reconstructive surgery followed by early active rehabilitation can be considered a reliable procedure that leads to substantial improvements in grip and pinch strength and activity performance among patients with tetraplegia. Copyright © 2016 American Congress of

  2. Dr. Buzby’s ToeGrips® Application Results in Minimal Changes in Kinetic Gait Parameters in Normal Dogs

    Directory of Open Access Journals (Sweden)

    James K. Roush

    2017-07-01

    Full Text Available Poor traction on slick surfaces is difficult for dogs with neurologic deficits, osteoarthritis, or recovering from injury or surgery. Many dogs respond inappropriately to slick surfaces by decreasing digital pad-floor contact and extending their toenails. A device marketed to increase paw-floor friction in dogs was evaluated. Fifteen normal dogs underwent kinetic gait analysis before and after application of Dr. Buzby’s ToeGrips®. Ground reaction forces, including vertical peak force (VPF and impulse for each limb, were measured and compared between pre- and post-application values. Stance time was significantly increased in all limbs after toe grip application. Stride velocity was slower in all limbs but significantly slower only in the left forelimb. VPF was significantly deceased in both hindlimbs after toe grip application, but the decrease was within the group SDs. Vertical impulse was significantly increased in both forelimbs and in the right hindlimb. Dr. Buzby’s ToeGrips® result in a slower gait, with slightly decreased VPF in the hindlimbs and increased effort for propulsion kinetic changes were of minor magnitude and unlikely to be clinically relevant.

  3. Progress on the interface between UPP and CPRHS (Cask and Plug Remote Handling System) tractor/gripping tool for ITER

    International Nuclear Information System (INIS)

    Rosa, Elena V.; Rios, Luis; Queral, Vicente

    2013-01-01

    Highlights: ► UPP interface requirements in the plug RH extraction/insertion for ITER. ► Analyze of maximum misalignment between port duct and port cell. ► Friction study between plug skids and VV port/ramp rails during the plug transfer. ► Definition of the tolerance in the plug skids to avoid the plug jamming. ► Concepts of gripping tools based on one gripping point and avoiding force feedback. -- Abstract: EFDA finances a training programme called Goal Oriented Training Programme for Remote Handling (GOT RH), whose goal is to train engineers in Remote Handling for ITER. As part of this training programme, the conceptual design of the mechanical interface between Upper Port Plug (UPP) and Cask and Plug Remote Handling System (CPRHS) as well as the conceptual design of the needed tools for UPP Remote Handling is carried out. The paper presents the conceptual design of the UPP/Gripping Tool Interface. This includes the conceptual design of the gripping tool for introducing/removing the UPP in/from the ITER port and the mechanical features on both sides of the UPP/Gripping Tool Interface (e.g. alignment features, mechanical connectors, fasteners). In order to develop the design of the interface between UPP and CPRHS it is necessary to first identify the functional requirements of the Transfer Cask System (TCS) and the CPRHS, such as required degrees of freedom (DoF), required performances of system, geometrical constraints, loading conditions, alignment requirements, RAMI requirements. These requirements are the input data for the design of the interface between UPP and gripping tool and some of them are also described in the paper

  4. Interactive effects of music tempi and intensities on grip strength and subjective affect.

    Science.gov (United States)

    Karageorghis, C I; Cheek, P; Simpson, S D; Bigliassi, M

    2018-03-01

    Pretask music is widely used by athletes albeit there is scant empirical evidence to support its use. The present study extended a line of work into pretask music by examining the interactive effects of music tempo and intensity (volume) on the performance of a simple motor skill and subjective affect. A 2 × 2 within-subjects factorial design was employed with an additional no-music control, the scores from which were used as a covariate. A sample of 52 male athletes (M age  = 26.1 ± 4.8 years) was exposed to five conditions: fast/loud (126 bpm/80 dBA), fast/quiet (126 bpm/70 dBA), slow/loud (87 bpm/80 dBA), slow/quiet (87 bpm/70 dBA) music, and a no-music control. Dependent variables were grip strength, measured with a handgrip dynamometer, and subjective affect, assessed by use of the Affect Grid. The tempo and intensity components of music had interactive effects for grip strength but only main effects for subjective affect. Fast-tempo music played at a high intensity yielded the highest grip strength, while fast-tempo music played at a low-intensity resulted in much lower grip strength (M diff.  = -1.11 Force kg). For affective valence, there were main effects of tempo and intensity, with fast and loud music yielding the highest scores. For affective arousal, there was no difference between tempi although there was between intensities, with the high-intensity condition yielding higher scores. The present findings indicate the utility of fast/loud pretask music in enhancing affective valence and arousal in preparation for a simple or gross motor task. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  5. Finger pressure adjustments to various object configurations during precision grip in humans and monkeys.

    Science.gov (United States)

    Viaro, Riccardo; Tia, Banty; Coudé, Gino; Canto, Rosario; Oliynyk, Andriy; Salmas, Paola; Masia, Lorenzo; Sandini, Giulio; Fadiga, Luciano

    2017-06-01

    In this study, we recorded the pressure exerted onto an object by the index finger and the thumb of the preferred hand of 18 human subjects and either hand of two macaque monkeys during a precision grasping task. The to-be-grasped object was a custom-made device composed by two plates which could be variably oriented by a motorized system while keeping constant the size and thus grip dimension. The to-be-grasped plates were covered by an array of capacitive sensors to measure specific features of finger adaptation, namely pressure intensity and centroid location and displacement. Kinematic measurements demonstrated that for human subjects and for monkeys, different plate configurations did not affect wrist velocity and grip aperture during the reaching phase. Consistently, at the instant of fingers-plates contact, pressure centroids were clustered around the same point for all handle configurations. However, small pressure centroid displacements were specifically adopted for each configuration, indicating that both humans and monkeys can display finger adaptation during precision grip. Moreover, humans applied stronger thumb pressure intensity, performed less centroid displacement and required reduced adjustment time, as compared to monkeys. These pressure patterns remain similar when different load forces were required to pull the handle, as ascertained by additional measurements in humans. The present findings indicate that, although humans and monkeys share common features in motor control of grasping, they differ in the adjustment of fingertip pressure, probably because of skill and/or morphology divergences. Such a precision grip device may form the groundwork for future studies on prehension mechanisms. © 2017 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  6. GRIP GLOBAL HAWK NAVIGATION AND HOUSEKEEPING DATA V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GRIP Global Hawk Navigation and Housekeeping data was collected from August 15, 2010 to September 24, 2010 during the Genesis and Rapid Intensification Processes...

  7. GRIP DOPPLER AEROSOL WIND LIDAR (DAWN) V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GRIP Doppler Aerosol WiNd Lidar (DAWN) Dataset was collected by the Doppler Aerosol WiNd (DAWN), a pulsed lidar, which operated aboard a NASA DC-8 aircraft...

  8. GRIP DC-8 NAVIGATION AND HOUSEKEEPING DATA V1

    Data.gov (United States)

    National Aeronautics and Space Administration — This dataset contains aircraft navigational data obtained during the GRIP campaign (15 Aug 2010 - 30 Sep 2010). The NASA DC-8 is outfitted with a navigational...

  9. GRIP DOPPLER AEROSOL WIND LIDAR (DAWN) V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The Doppler Aerosol WiNd (DAWN), a pulsed lidar, operated aboard a NASA DC-8 aircraft during the Genesis and Rapid Intensification Processes (GRIP) field campaign....

  10. GRIP AIRBORNE SECOND GENERATION PRECIPITATION RADAR (APR-2) V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GRIP Airborne Second Generation Precipitation Radar (APR-2) dataset was collected from the Second Generation Airborne Precipitation Radar (APR-2), which is a...

  11. GRIP WB-57 NAVIGATION AND HOUSEKEEPING DATA V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GRIP WB-57 Navigation and Housekeeping data was collected on flight days occuring between July 13 , 2010 to September 17, 2010 during the Genesis and Rapid...

  12. GRIP DC-8 METEOROLOGICAL MEASUREMENT SYSTEM (MMS) V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GRIP DC-8 Meteorological measurement System (MMS) dataset was collected by the Meteorological Measurement System (MMS), which provides high-resolution, accurate...

  13. GRIP BARBADOS/CAPE VERDE RADIOSONDE V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GRIP Barbados/Cape Verde radiosonde data set consists of generally two soundings per day (06Z and 12Z) launched from Barbados, and one sounding per day (12Z)...

  14. GRIP HIGH-ALTITUDE MMIC SOUNDING RADIOMETER (HAMSR) V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GRIP High-Altitude MMIC Sounding Radiometer (HAMSR) dataset was collectd by the High Altitude monolithic microwave integrated Circuit (MMIC) Sounding Radiometer...

  15. Grip op werkstress. Mindfulness ontstresst maatschappelijk werkers

    Directory of Open Access Journals (Sweden)

    Jen van Horen

    2014-03-01

    Full Text Available Taking control over work related stress. Mindfulness destresses social workersStress is a major social problem. Due to the increasing workload and the content of the work, social workers are at risk to develop stress (symptoms. The physical and psychological consequences of prolonged stress are serious. By living healthy, optimize working conditions and applying mindfulness, stress can be reduced. Mindfulness is an effective and useful way to reduce stress. It increases the resistance of workers against stress, improves brainfunctions and therefore has a positive effect on the performance. These effects are great, but they are still weakly methodologically substantiated. A pilot project within the youthcare though, was enthusiastically received and proves to be effective against stress symptoms. The exercises that are part of this pilot fit well with the needs of employees. For organizations mindfulnesstrainings are a time-and cost-effective way of structural stress prevention.Grip op werkstress. Mindfulness ontstresst maatschappelijk werkersStress is een omvangrijk maatschappelijk probleem. Door de toenemende werkdruk en de inhoud van het werk zijn maatschappelijk werkers een risicogroep om stress en stressklachten te ontwikkelen. De fysieke en psychische gevolgen die langdurige stress met zich meebrengt zijn ernstig. Door gezond te leven, de arbeidsomstandigheden te optimaliseren en mindfulness toe te passen kan stress terug worden gedrongen. Mindfulness is een effectieve en bruikbare manier om stress te verminderen. Het vergroot de weerbaarheid van werknemers tegen stress, het verbetert de hersenwerking en heeft daardoor een positief effect op het functioneren. Grote effecten dus, maar wel nog methodologisch zwak onderbouwd. Een pilot binnen de jeugdzorg op het gebied van mindfulness is enthousiast ontvangen en blijkt effectief tegen stressklachten. De oefeningen die onderdeel uitmaken van deze pilot sluiten goed aan bij de behoeften van

  16. Tensile Properties of Dyneema SK76 Single Fibers at Multiple Loading Rates Using a Direct Gripping Method

    Science.gov (United States)

    2014-06-01

    higher tensile modulus and good resistance to chemical and physical degradation . Due to an increasing need for numerical modeling capability of...grip are tightened until the fiber is squeezed with enough force by the polycarbonate clamping blocks to ensure that the fiber will not slip out...629–636. 20 26. Liu, X.; Yu, W. Evaluation of the Tensile Properties and Thermal Stability of Ultrahigh- Molecular-Weight Polyethylene Fibers

  17. Design and Analysis of a Fibre-Shaped Micro-Actuator for Robotic Gripping

    Directory of Open Access Journals (Sweden)

    Alberto Borboni

    2013-03-01

    Full Text Available A prototype of an automatic micropositioning system was developed. This prototype uses a shape memory alloy (SMA actuator, a dedicated PI controller and a piece of software to command a desired motion profile for the actuator. The proposed micropositioning system is characterized by a 4 mm stroke, a 1 μm resolution and a 70 g nominal force and can be commanded directly from a personal computer and without human retroaction. The closed loop positioning resolution (1 μm is obtained in spite of inaccurate system behaviour during its movement.

  18. Simple and Reliable Method to Estimate the Fingertip Static Coefficient of Friction in Precision Grip.

    Science.gov (United States)

    Barrea, Allan; Bulens, David Cordova; Lefevre, Philippe; Thonnard, Jean-Louis

    2016-01-01

    The static coefficient of friction (µ static ) plays an important role in dexterous object manipulation. Minimal normal force (i.e., grip force) needed to avoid dropping an object is determined by the tangential force at the fingertip-object contact and the frictional properties of the skin-object contact. Although frequently assumed to be constant for all levels of normal force (NF, the force normal to the contact), µ static actually varies nonlinearly with NF and increases at low NF levels. No method is currently available to measure the relationship between µ static and NF easily. Therefore, we propose a new method allowing the simple and reliable measurement of the fingertip µ static at different NF levels, as well as an algorithm for determining µ static from measured forces and torques. Our method is based on active, back-and-forth movements of a subject's finger on the surface of a fixed six-axis force and torque sensor. µ static is computed as the ratio of the tangential to the normal force at slip onset. A negative power law captures the relationship between µ static and NF. Our method allows the continuous estimation of µ static as a function of NF during dexterous manipulation, based on the relationship between µ static and NF measured before manipulation.

  19. Effect of toothbrush grip on plaque removal during manual toothbrushing in children.

    Science.gov (United States)

    Sharma, Sarika; Yeluri, Ramakrishna; Jain, Amit A; Munshi, Autar K

    2012-01-01

    Toothbrushing is fundamental to oral hygiene. Children differ in manual dexterity and their grip on toothbrushes. We videotaped toothbrushing sessions and observed the grip type, duration of brushing, and brushing technique used among 100 children aged 8-12 years. We then investigated the association between grip type and plaque removal, using plaque scores obtained at various time points. We further examined the effect on plaque scores of standardizing both brushing technique and duration among the same participants. The most common grip was the distal oblique, followed by the oblique; the spoon and precision grips were rare, and no child used a power grip. Mean brushing duration for most children was 1.43 ± 0.85 min, and the most common brushing technique was horizontal scrubbing. We conclude that grip preference is inherent and that the distal oblique grip was better than the oblique grip in removing plaque.

  20. Inaccurate preoperative imaging assessment on biliary anatomy not increases biliary complications after living donor liver transplantation

    International Nuclear Information System (INIS)

    Xu Xiao; Wei Xuyong; Ling Qi; Wang Kai; Bao Haiwei; Xie Haiyang; Zhou Lin; Zheng Shusen

    2012-01-01

    Backgrounds and aims: Accurate assessment of graft bile duct is important to plan surgical procedure. Magnetic resonance cholangiopancreatography (MRCP) has become an important diagnostic procedure in evaluation of pancreaticobiliary ductal abnormalities and has been reported as highly accurate. We aim to estimate the efficacy of preoperative MRCP on depicting biliary anatomy in living donor liver transplantation (LDLT), and to determine whether inaccurate preoperative imaging assessment would increase the biliary complications after LDLT. Methods: The data of 118 cases LDLT were recorded. Information from preoperative MRCP was assessed using intraoperative cholangiography (IOC) as the gold standard. The possible risk factors of recipient biliary complications were analyzed. Results: Of 118 donors, 84 had normal anatomy (type A) and 34 had anatomic variants (19 cases of type B, 9 cases of type C, 1 case of type E, 2 cases of type F and 3 cases of type I) confirmed by IOC. MRCP correctly predicted all 84 normal cases and 17 of 34 variant cases, and showed an accuracy of 85.6% (101/118). The incidence of biliary complications was comparable between cases with accurate and inaccurate classification of biliary tree from MRCP, and between cases with normal and variant anatomy of bile duct. While cases with graft duct opening ≤5 mm showed a significant higher incidence of total biliary complications (21.1% vs. 6.6%, P = 0.028) and biliary stricture (10.5% vs. 1.6%, P = 0.041) compared with cases with large duct opening >5 mm. Conclusion: MRCP could correctly predict normal but not variant biliary anatomy. Inaccurate assessment of biliary anatomy from MRCP not increases the rate of biliary complications, while small-sized graft duct may cause an increase in biliary complications particularly biliary stricture after LDLT.

  1. Colloquium: Gripped by light: Optical binding

    Czech Academy of Sciences Publication Activity Database

    Dholakia, K.; Zemánek, Pavel

    2010-01-01

    Roč. 82, č. 2 (2010), s. 1767-1791 ISSN 0034-6861 R&D Projects: GA ČR GA202/09/0348; GA MŠk(CZ) LC06007 Institutional research plan: CEZ:AV0Z20650511 Keywords : discrete-dipole approximation * artificial kerr medium * focused laser-beam * near-field optics * radiation pressure * electromagnetic force * trapping force * nonlinear nanosuspensions * spherical nanoparticles * metal nanoparticles Subject RIV: BH - Optics , Masers, Lasers Impact factor: 51.695, year: 2010

  2. The Impact of Inaccurate Internet Health Information in a Secondary School Learning Environment

    Science.gov (United States)

    Edwards, Christine; Richards-Kortum, Rebecca

    2008-01-01

    Background Patients in the United States commonly use the Internet to acquire health information. While a significant amount of health-related information is available on the Internet, the accuracy of this information is highly variable. Objectives The objective of the study was to determine how effectively students can assess the accuracy of Internet-based material when gathering information on a controversial medical topic using simple keyword searches. Methods A group of 34 students from the science magnet high school in Houston, Texas searched for the terms “vaccine safety” and “vaccine danger” using Google and then answered questions regarding the accuracy of the health information on the returned sites. The students were also asked to describe the lessons they learned in the exercise and to answer questions regarding the strength of evidence for seven statements regarding vaccinations. Because of the surprising revelation that the majority of students left the exercise with inaccurate information concerning the safety and efficacy of vaccines, these same students participated in a follow-up study in which a fact-based vaccine video was shown, after which the assessment of student knowledge was repeated. Results Of the 34 participants, 20 (59%) thought that the Internet sites were accurate on the whole, even though over half of the links (22 out of 40, 55%) that the students viewed were, in fact, inaccurate on the whole. A high percentage of the students left the first exercise with significant misconceptions about vaccines; 18 of the 34 participants (53%) reported inaccurate statements about vaccines in the lessons they learned. Of the 41 verifiable facts about vaccines that were reported by participants in their lessons-learned statement, 24 of those facts (59%) were incorrect. Following presentation of the film, the majority of students left the exercise with correct information about vaccines, based on their lessons-learned statement. In this case

  3. Near-Nash equilibrium strategies for LQ differential games with inaccurate state information

    Directory of Open Access Journals (Sweden)

    2006-01-01

    Full Text Available ε -Nash equilibrium or “near equilibrium” for a linear quadratic cost game is considered. Due to inaccurate state information, the standard solution for feedback Nash equilibrium cannot be applied. Instead, an estimation of the players' states is substituted into the optimal control strategies equation obtained for perfect state information. The magnitude of the ε in the ε -Nash equilibrium will depend on the quality of the estimation process. To illustrate this approach, a Luenberger-type observer is used in the numerical example to generate the players' state estimates in a two-player non-zero-sum LQ differential game.

  4. Friction between finger flexor tendons and the pulley system in the crimp grip position.

    Science.gov (United States)

    Moor, Beat K; Nagy, Ladislav; Snedeker, Jess G; Schweizer, Andreas

    2009-01-01

    Disruption of the finger flexor tendon pulleys are the most often occurring injury in rock climbers due to bowstringing of tendons during crimp grip position. The aim of this study was to quantify friction between the flexor tendons and pulleys and the influence of high load and speed of movement as a potential factor of pulley disruption. Friction between the flexor tendons and pulleys of eight human cadaver fingers was indirectly determined using an isokinetic movement device. During flexion and extension movement with rotational speed from 30 to 210 deg/s in the proximal interphalangeal joint and with load from 20 to 100 N to the flexor tendons the flexion force at the tip of the finger was measured. With 40 N loaded flexor tendons the force at the fingertip was 14.5 N (SD1.5) during extension and 12.6N (SD1.3) during flexion movement. Corresponding force difference of 12.9% and 3.77 N (SD0.6) force of friction can be calculated. Friction peaked at 85.8 degrees (SD2.05) of flexion of the proximal interphalangeal joint. Different speed of motion and load to the flexor tendons did not influence force difference other than linear. Considerable friction between flexor tendons and pulleys is apparent and therefore may have an influence on pulley injuries. Particularly during the crimp grip position where the proximal interphalangeal joint is flexed about 90 degrees shows the greatest amount of friction. However there was no change of friction during high speed motion and no other than linear increase during high load.

  5. Dextrous gripping in a hazardous environment

    International Nuclear Information System (INIS)

    Jongkind, W.

    1993-01-01

    Existing dextrous grippers are presented and compared, tasks to be performed in the hazardous environment are analyzed, and recommendations on gripper design and configuration are given. The outcome is a proposal for a dextrous gripper consisting of three antropomorphic fingers and an active palm. Sensor and actuator issues have been investigated and a selection of them has been made with respect to applicability in the hazardous environment. Theoretical contact issues were investigated and contacts have been modelled accordingly, followed by a kinematical analysis of the proposed gripper. Force and motion equations have been derived, and finger force distribution and computation has been analyzed. Grasp planning, the determination for a given task of a sequence of postures, to gurantee the safe and robust grasping of an object has been investigated. The determination of postures resulting in the designation of the number and categories of contact points before the fingers of the gripper contact the object is a matter of high-level grasping. The post-contact phase of the grasp, where set points for position and/or force have to be controlled, a matter of low-level grasp planning, has been investigated. The dissertation concluded with an investigation into the control of the gripper to achieve reliable grasps. The aim was to arrive at a controller that can comply with varying external forces and that can cope with imprecise known objects and imprecise task descriptions. Also the controlling of grasping forces as aimed at. The resulting gripper is radiation resistant. The methodology worked out in the dissertation is currently being applied to the design of a gripper able to operate in a hazardous nuclear environment. (orig./HP)

  6. A COMPARATIVE STUDY TO FIND OUT IMMEDIATE EFFECTIVENESS OF MOVEMENT WITH MOBILIZATION VERSUS ELBOW ORTHOSIS ON PAIN AND GRIP STRENGTH IN LATERAL EPICONDYLITIS IN HOUSEWIVES

    Directory of Open Access Journals (Sweden)

    Trishna Kakati

    2015-12-01

    both Mulligan’s MWM technique and counter force elbow orthosis produces significant decrease in pain and improvement in grip strength immediately after treatment. It has been seen that Mulligan’s MWM is better than counter force elbow orthosis in relieving pain (p=0.03. Increase in hand grip strength does not differ remarkably in both treatment groups.

  7. Comparative study of maximum isometric grip strength in different sports

    OpenAIRE

    Noé Gomes Borges Junior; Susana Cristina Domenech; Jonathan Ache Dias; Affonso Celso Kulevicz da Silva; Yoshimasa Sagawa Junior

    2009-01-01

    http://dx.doi.org/10.5007/1980-0037.2009v11n3p292   The objective of this study was to compare maximum isometric grip strength (Fmax)between different sports and between the dominant (FmaxD) and non-dominant (FmaxND) hand. Twenty-nine male aikido (AI), jiujitsu (JJ), judo (JU) and rowing (RO) athletes and 21non-athletes (NA) participated in the study. The hand strength test consisted of maintainingmaximum isometric grip strength for 10 seconds using a hand dynamometer. The position of...

  8. Inverting reflections using full-waveform inversion with inaccurate starting models

    KAUST Repository

    AlTheyab, Abdullah

    2015-08-19

    We present a method for inverting seismic reflections using full-waveform inversion (FWI) with inaccurate starting models. For a layered medium, near-offset reflections (with zero angle of incidence) are unlikely to be cycle-skipped regardless of the low-wavenumber velocity error in the initial models. Therefore, we use them as a starting point for FWI, and the subsurface velocity model is then updated during the FWI iterations using reflection wavepaths from varying offsets that are not cycle-skipped. To enhance low-wavenumber updates and accelerate the convergence, we take several passes through the non-linear Gauss-Seidel iterations, where we invert traces from a narrow range of near offsets and finally end at the far offsets. Every pass is followed by applying smoothing to the cumulative slowness update. The smoothing is strong at the early stages and relaxed at later iterations to allow for a gradual reconstruction of the subsurface model in a multiscale manner. Applications to synthetic and field data, starting from inaccurate models, show significant low-wavenumber updates and flattening of common-image gathers after many iterations.

  9. The Effects of Counterforce Brace Size on the Wrist Range of Motility, Pain, Grip & Wrist Extension Sterngth in Normal Subjects and Patients with Tennis Elbow

    Directory of Open Access Journals (Sweden)

    Ali Asghar Jameh-Bozorgi

    2006-04-01

    Full Text Available Objective: Counter force brace is one of the most usefull treatments for lateral opicondylitis (Tennis elbow because it decreases grip pain and increases the power of grip, power of wrist extension and Wrist Range of Motility. The purpose of this quasi experimental (repeated measurementsstudy was to determine the effect of 3 counterforce brace sizes on the wrist R.O.M, grip and wrist extension strength and pain intensity in two groups of healthy subjects and patients with tennis elbow. Materials & Methods: 18 normal subjects & 18 patients with tennis elbow were selected simple conveniently and were tested with no brace and 3 size of counterforce (1,2 and 3 inches. The R.O.M , strength and pain intensity were measured by jamar goniometry and Nicholas MMT dynamometry & VAS, respectively. Results: 1 With all sizes there was a significant decrease of R.O.M on normal subjects but no significant difference in patients. 2 There was a significant decrease of grip strength with 1-inch brace in normal subjects but a significant increase of grip strength with 2 and 3-inch brace in patiens. 3 All sizes of brace caused significant decrease of extension strength in normal subjects but increase in patients. 4All size caused significant decrease of pain intensity that was more considerable in the case of 2 and 3 inch size. Conclusion: The results shows that the counterforce brace may be considered as an effective treatment for increasing strength and decreasing pain in patients with tennis elbow.

  10. Hand Grip Strength Vs. Sprint Effectiveness in Amputee Soccer Players.

    Science.gov (United States)

    Wieczorek, Marta; Wiliński, Wojciech; Struzik, Artur; Rokita, Andrzej

    2015-11-22

    Amputee soccer is one of the types of soccer designed for the disabled, especially those who have undergone amputations, as well as those with extremity dysfunction. The objective of the study was to find the relationship between hand grip strength and sprint time in amputee soccer players. Thirteen field amputee soccer players participated in the study. A SAEHAN hydraulic hand dynamometer manufactured by Jamar was used for hand grip strength measurements. The sprint running test was conducted over a distance of 30 m. The Fusion Smart Speed System was employed for running time measurements. No statistically significant relationships were found between hand grip strength of the left or right hand, and sprint times over 1, 5, 10, 15, 20, 25 and 30 m. Analysis of the running velocity curve of the subjects showed an interesting profile characterized by a 15 meter-long acceleration phase and a significant velocity increase over a distance of 20 - 25 m. The study suggests that there is no relationship between hand grip strength and sprint effectiveness in amputee soccer players. The specificity of locomotion with the use of elbow crutches among elite Polish amputee soccer players probably accounts for the profile of the sprint velocity curve. Extension of the acceleration phase in the sprint run and a velocity increase in the subsequent part of the run were observed.

  11. Hand Grip Strength Vs. Sprint Effectiveness in Amputee Soccer Players

    Directory of Open Access Journals (Sweden)

    Wieczorek Marta

    2015-12-01

    Full Text Available Amputee soccer is one of the types of soccer designed for the disabled, especially those who have undergone amputations, as well as those with extremity dysfunction. The objective of the study was to find the relationship between hand grip strength and sprint time in amputee soccer players. Thirteen field amputee soccer players participated in the study. A SAEHAN hydraulic hand dynamometer manufactured by Jamar was used for hand grip strength measurements. The sprint running test was conducted over a distance of 30 m. The Fusion Smart Speed System was employed for running time measurements. No statistically significant relationships were found between hand grip strength of the left or right hand, and sprint times over 1, 5, 10, 15, 20, 25 and 30 m. Analysis of the running velocity curve of the subjects showed an interesting profile characterized by a 15 meter-long acceleration phase and a significant velocity increase over a distance of 20 – 25 m. The study suggests that there is no relationship between hand grip strength and sprint effectiveness in amputee soccer players. The specificity of locomotion with the use of elbow crutches among elite Polish amputee soccer players probably accounts for the profile of the sprint velocity curve. Extension of the acceleration phase in the sprint run and a velocity increase in the subsequent part of the run were observed.

  12. Bone metabolism and hand grip strength response to aerobic versus ...

    African Journals Online (AJOL)

    Bone metabolism and hand grip strength response to aerobic versus resistance exercise training in non-insulin dependent diabetic patients. ... Objective: The aim of this study was to compare the changes in handgrip strength and bone metabolism after 6 months between aerobic and resistance exercise training in ...

  13. Grip and Pinch Strength Norms for Michigan Workers

    Directory of Open Access Journals (Sweden)

    Joel M. Phillips M.S., OTRL

    2013-06-01

    Full Text Available The purpose of this study was to create a norm reference of current grip and pinch strength norms for working-age Michigan adults. This normative study included a convenience sample of 179 volunteers who were employees at car plants in South East Michigan or hospital sites in West Michigan. Participants’ ages ranged from between 20 and 62 years of age with a mean age of 49.15 years. There were 78 females (44% and 101 males (56%. Subjects were classified by gender and in the age categories of ages 20 to 49 years and ages 50-62 years. Grip and pinch strength norms were collected following the American Society of Hand Therapy protocol. The norms from these working adults were calculated with descriptive statistics for males and females in two age classifications: ages 20 to 49 and ages 50 to 62 years. Standard Errors (SE are better than the 1985 norms for both males and females ages 20 to 49 years. SEs are higher than the ages 20 to 49 years’ norms for the ages 50 to 62 years age categories in both males and females. These norms offer a point of comparison for clinicians to use for clients in Michigan who are ages 20 to 62 years and who have a goal to improve their grip strength. Clients’ grip and pinch strength could be compared to their age level or gender norms using the comparison for one standard deviation above, below, or at the means.

  14. Control of finger forces during fast, slow and moderate rotational hand movements.

    Science.gov (United States)

    Kazemi, Hamed; Kearney, Robert E; Milner, Theodore E

    2014-01-01

    The goal of this study was to investigate the effect of speed on patterns of grip forces during twisting movement involving forearm supination against a torsional load (combined elastic and inertial load). For slow and moderate speed rotations, the grip force increased linearly with load torque. However, for fast rotations in which the contribution of the inertia to load torque was significantly greater than slower movements, the grip force-load torque relationship could be segmented into two phases: a linear ascending phase corresponding to the acceleration part of the movement followed by a plateau during deceleration. That is, during the acceleration phase, the grip force accurately tracked the combined elastic and inertial load. However, the coupling between grip force and load torque was not consistent during the deceleration phase of the movement. In addition, as speed increased, both the position and the force profiles became smoother. No differences in the baseline grip force, safety margin to secure the grasp during hold phase or the overall change in grip force were observed across different speeds.

  15. The Test of Inaccurate Position of Renography Detector to Relative UptakeFigure and Individual Excretion

    International Nuclear Information System (INIS)

    Bambang-Supardiyono; Prayitno

    2000-01-01

    Accuracy of detector position toward the kidney location (preciseposition) in renography will resulting the maximum count figure, detectorposition change from the precise point (inaccurate) will decreasing the countrate. Therefore for it had been simulated the influence of count figure ofright kidney (fixed left kidney count) ± 5 % to ± 20 % to relativeuptake figure and individual excretion. Based on the calculation it was foundthat the relation of detector position ± 0.5 cm to ± 2 cm from theprecise point will have effect to relative uptake figure ± (1.25 % to 5.00%), the fixed individual excretion figure. The change is still can beaccepted because the qualitative information with 10 % accuracy is stillacceptable. (author)

  16. Study on the collision-mechanical properties of tomatoes gripped by ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-12-15

    Dec 15, 2009 ... The data of collision-mechanical property of tomatoes gripped by robot fingers are important for the gripping control of tomato harvesting robot. In the study, tests of controlling the fingers to grip tomatoes were conducted to ascertain the effects of input current, motor speed and impact positions on the impact ...

  17. Inaccurate DNA synthesis in cell extracts of yeast producing active human DNA polymerase iota.

    Directory of Open Access Journals (Sweden)

    Alena V Makarova

    2011-01-01

    Full Text Available Mammalian Pol ι has an unusual combination of properties: it is stimulated by Mn(2+ ions, can bypass some DNA lesions and misincorporates "G" opposite template "T" more frequently than incorporates the correct "A." We recently proposed a method of detection of Pol ι activity in animal cell extracts, based on primer extension opposite the template T with a high concentration of only two nucleotides, dGTP and dATP (incorporation of "G" versus "A" method of Gening, abbreviated as "misGvA". We provide unambiguous proof of the "misGvA" approach concept and extend the applicability of the method for the studies of variants of Pol ι in the yeast model system with different cation cofactors. We produced human Pol ι in baker's yeast, which do not have a POLI ortholog. The "misGvA" activity is absent in cell extracts containing an empty vector, or producing catalytically dead Pol ι, or Pol ι lacking exon 2, but is robust in the strain producing wild-type Pol ι or its catalytic core, or protein with the active center L62I mutant. The signature pattern of primer extension products resulting from inaccurate DNA synthesis by extracts of cells producing either Pol ι or human Pol η is different. The DNA sequence of the template is critical for the detection of the infidelity of DNA synthesis attributed to DNA Pol ι. The primer/template and composition of the exogenous DNA precursor pool can be adapted to monitor replication fidelity in cell extracts expressing various error-prone Pols or mutator variants of accurate Pols. Finally, we demonstrate that the mutation rates in yeast strains producing human DNA Pols ι and η are not elevated over the control strain, despite highly inaccurate DNA synthesis by their extracts.

  18. Reliability of the Bulb Dynamometer for Assessing Grip Strength

    Directory of Open Access Journals (Sweden)

    Colleen Maher

    2018-04-01

    Full Text Available Background: Hand function is an overall indicator of health and is often measured using grip strength. Handheld dynamometry is the most common method of measuring grip strength. The purpose of this study was to determine the inter-rater and test-retest reliability, the reliability of one trial versus three trials, and the preliminary norms for a young adult population using the Baseline® Pneumatic Squeeze Bulb Dynamometer (30 psi. Methods: This study used a one-group methodological design. One hundred and three healthy adults (30 males and 73 females were recruited. Six measurements were collected for each hand per participant. The data was analyzed using Intraclass Correlation Coefficients (ICC two-way effects model (2,2 and paired-samples t-tests. Results: The ICC for inter-rater reliability ranged from 0.955 to 0.977. Conclusion: The results of this study suggest that the bulb dynamometer is a reliable tool to measure grip strength and should be further explored for reliable and valid use in diverse populations and as an alternative to the Jamar dynamometer.

  19. Methods for detecting and correcting inaccurate results in inductively coupled plasma-atomic emission spectrometry

    Science.gov (United States)

    Chan, George C. Y. [Bloomington, IN; Hieftje, Gary M [Bloomington, IN

    2010-08-03

    A method for detecting and correcting inaccurate results in inductively coupled plasma-atomic emission spectrometry (ICP-AES). ICP-AES analysis is performed across a plurality of selected locations in the plasma on an unknown sample, collecting the light intensity at one or more selected wavelengths of one or more sought-for analytes, creating a first dataset. The first dataset is then calibrated with a calibration dataset creating a calibrated first dataset curve. If the calibrated first dataset curve has a variability along the location within the plasma for a selected wavelength, errors are present. Plasma-related errors are then corrected by diluting the unknown sample and performing the same ICP-AES analysis on the diluted unknown sample creating a calibrated second dataset curve (accounting for the dilution) for the one or more sought-for analytes. The cross-over point of the calibrated dataset curves yields the corrected value (free from plasma related errors) for each sought-for analyte.

  20. Grip strength measured by high precision dynamometry in healthy subjects from 5 to 80 years.

    Science.gov (United States)

    Hogrel, Jean-Yves

    2015-06-10

    Grip strength is a variable which may be important to measure and follow in various populations. A new dynamometer with high accuracy and sensitivity has recently been developed to assess grip strength. The objectives of this work were to provide norms of maximal isometric grip strength measured with this new dynamometer (the MyoGrip device), to assess the reliability of measurements, to compare the measurements obtained with MyoGrip and Jamar dynamometers and finally to establish predictive equations from a population of healthy subjects (children and adults). Measurements of maximal isometric grip strength using the MyoGrip and the Jamar (which is considered as the gold-standard) were performed on 346 healthy subjects aged from 5 to 80 years. Test-retest reliability for both devices was assessed on 77 subjects. Predictive equations were computed on subjects younger than 60 years of age in order to avoid the effects of aging on strength. This study provides norms for isometric grip strength for health subjects from 5 to 80 years. Reliability of the MyoGrip device was excellent (intraclass correlation coefficient: 0.967). Despite good correlation between devices, the Jamar tended to overestimate maximal grip strength by about 14 %. A single predictive equation for men and women, adults and children incorporating hand circumference only can be used to compute the predicted theoretical maximal grip strength. The MyoGrip device is a reliable tool for measuring isometric grip strength. Owing to its unique metrological features, it can be used in very weak patients or in any situation where high precision and accuracy are required.

  1. Muscle strength: clinical and prognostic value of hand-grip dynamometry.

    Science.gov (United States)

    Bohannon, Richard W

    2015-09-01

    Grip strength measured by dynamometry is well established as an indicator of muscle status, particularly among older adults. This review was undertaken to provide a synopsis of recent literature addressing the clinical and prognostic value of hand-grip dynamometry. Numerous large-scale normative grip strength projects have been published lately. Other recent studies have reinforced the concurrent relationship of grip strength with measures of nutritional status or muscle mass and measures of function and health status. Studies published in the past few years have confirmed the value of grip strength as a predictor of mortality, hospital length of stay, and physical functioning. As a whole, the recent literature supports the use of hand-grip dynamometry as a fundamental element of the physical examination of patients, particularly if they are older adults.

  2. Discrimination of handlebar grip samples by fourier transform infrared microspectroscopy analysis and statistics

    Directory of Open Access Journals (Sweden)

    Zeyu Lin

    2017-01-01

    Full Text Available In this paper, the authors presented a study on the discrimination of handlebar grip samples, to provide effective forensic science service for hit and run traffic cases. 50 bicycle handlebar grip samples, 49 electric bike handlebar grip samples, and 96 motorcycle handlebar grip samples have been randomly collected by the local police in Beijing (China. Fourier transform infrared microspectroscopy (FTIR was utilized as analytical technology. Then, target absorption selection, data pretreatment, and discrimination of linked samples and unlinked samples were chosen as three steps to improve the discrimination of FTIR spectrums collected from different handlebar grip samples. Principal component analysis and receiver operating characteristic curve were utilized to evaluate different data selection methods and different data pretreatment methods, respectively. It is possible to explore the evidential value of handlebar grip residue evidence through instrumental analysis and statistical treatments. It will provide a universal discrimination method for other forensic science samples as well.

  3. Finger pad friction and its role in grip and touch.

    Science.gov (United States)

    Adams, Michael J; Johnson, Simon A; Lefèvre, Philippe; Lévesque, Vincent; Hayward, Vincent; André, Thibaut; Thonnard, Jean-Louis

    2013-03-06

    Many aspects of both grip function and tactile perception depend on complex frictional interactions occurring in the contact zone of the finger pad, which is the subject of the current review. While it is well established that friction plays a crucial role in grip function, its exact contribution for discriminatory touch involving the sliding of a finger pad is more elusive. For texture discrimination, it is clear that vibrotaction plays an important role in the discriminatory mechanisms. Among other factors, friction impacts the nature of the vibrations generated by the relative movement of the fingertip skin against a probed object. Friction also has a major influence on the perceived tactile pleasantness of a surface. The contact mechanics of a finger pad is governed by the fingerprint ridges and the sweat that is exuded from pores located on these ridges. Counterintuitively, the coefficient of friction can increase by an order of magnitude in a period of tens of seconds when in contact with an impermeably smooth surface, such as glass. In contrast, the value will decrease for a porous surface, such as paper. The increase in friction is attributed to an occlusion mechanism and can be described by first-order kinetics. Surprisingly, the sensitivity of the coefficient of friction to the normal load and sliding velocity is comparatively of second order, yet these dependencies provide the main basis of theoretical models which, to-date, largely ignore the time evolution of the frictional dynamics. One well-known effect on taction is the possibility of inducing stick-slip if the friction decreases with increasing sliding velocity. Moreover, the initial slip of a finger pad occurs by the propagation of an annulus of failure from the perimeter of the contact zone and this phenomenon could be important in tactile perception and grip function.

  4. GRIPS-Gamma-Ray burst Investigation via Polarimetry and Spectroscopy

    International Nuclear Information System (INIS)

    Greiner, J.

    2008-01-01

    The primary scientific goal of the GRIPS mission [1] is to revolutionize our understanding of the early universe using γ-ray bursts. We propose a new generation gamma-ray observatory capable of unprecedented spectroscopy over a wide range of γ-ray energies (200 keV-50 MeV) and of polarimetry (200-1000 keV). Secondary goals achievable by this mission include direct measurements of supernova interiors through γ-rays from radioactive decays, nuclear astrophysics with massive stars and novae, and studies of particle acceleration near compact stars, interstellar shocks, and clusters of galaxies

  5. Event-related brain potentials for goal-related power grips.

    Science.gov (United States)

    Westerholz, Jan; Schack, Thomas; Koester, Dirk

    2013-01-01

    Recent research has shown that neurophysiological activation during action planning depends on the orientation to initial or final action goals for precision grips. However, the neural signature for a distinct class of grasping, power grips, is still unknown. The aim of the present study was to differentiate between cerebral activity, by means of event-related potentials (ERPs), and its temporal organization during power grips executed with an emphasis on either the initial or final parts of movement sequences. In a grasp and transportation task, visual cues emphasized either the grip (the immediate goal) or the target location (the final goal). ERPs differed between immediate and final goal-cued conditions, suggesting different means of operation dependent on goal-relatedness. Differences in mean amplitude occurred earlier for power grips than for recently reported precision grips time-locked to grasping over parieto-occipital areas. Time-locked to final object placement, differences occurred within a similar time window for power and precision grips over frontal areas. These results suggest that a parieto-frontal network of activation is of crucial importance for grasp planning and execution. Our results indicate that power grip preparation and execution for goal-related actions are controlled by similar neural mechanisms as have been observed during precision grips, but with a distinct temporal pattern.

  6. Effects of hand grip exercise on shoulder joint internal rotation and external rotation peak torque.

    Science.gov (United States)

    Lee, Dong-Rour; Jong-Soon Kim, Laurentius

    2016-08-10

    The goal of this study is to analyze the effects of hand grip training on shoulder joint internal rotation (IR)/external rotation (ER) peak torque for healthy people. The research was conducted on 23 healthy adults in their 20 s-30 s who volunteered to participate in the experiment. Hand grip power test was performed on both hands of the research subjects before/after the test to study changes in hand grip power. Isokinetic machine was used to measure the concentric IRPT (internal rotation peak torque) and concentric ERPT (external rotation peak torque) at the velocity of 60°/sec, 90°/sec, and 180°/sec before/after the test. Hand grip training was performed daily on the subject's right hand only for four weeks according to exercise program. Finally, hand grip power of both hands and the maximum torque values of shoulder joint IR/ER were measured before/after the test and analyzed. There was a statistically significant difference in the hand grip power of the right hand, which was subject to hand grip training, after the experiment. Also, statistically significant difference for shoulder ERPT was found at 60°/sec. Hand grip training has a positive effect on shoulder joint IRPT/ERPT and therefore can help strengthen muscles around the shoulder without using weight on the shoulder. Consequently, hand grip training would help maintain strengthen the muscles around the shoulder in the early phase of rehabilitation process after shoulder surgery.

  7. Delayed grip relaxation and altered modulation of intracortical inhibition with aging

    Science.gov (United States)

    Motawar, Binal; Stinear, James W.; Lauer, Abigail W.; Ramakrishnan, V. Viswanathan; Seo, Na Jin

    2015-01-01

    Grip relaxation is a voluntary action that requires an increase in short-interval intracortical inhibition (SICI) in healthy young adults, rather than a simple termination of excitatory drive. The way aging affects this voluntary inhibitory action and timing of grip relaxation is currently unknown. The objective of this study was to examine aging-related delays in grip relaxation and SICI modulation for the flexor digitorum superficialis (FDS) muscle during grip relaxation. The main finding was that young adults increased SICI to relax their grips, whereas older adults did not increase SICI with a prolonged grip relaxation time (prelaxation time). A secondary experiment showed that both young and older adults did not change H reflex excitability during grip relaxation. Our data suggest that grip relaxation is mediated by increased cortical inhibitory output in young adults, and aging-related impairment in increasing cortical inhibitory output may hamper timely cessation of muscle activity. Our data also suggest a lesser role of the spinal circuits in grip muscle relaxation. This knowledge may contribute to understanding of aging-related movement deterioration and development of interventions for improving modulation of SICI to improve muscle relaxation and movement coordination. PMID:26686531

  8. SAO and Kelvin Waves in the EuroGRIPS GCMS and the UK Meteorological Offices Analyses

    Science.gov (United States)

    Amodei, M.; Pawson, S.; Scaife, A. A.; Lahoz, W.; Langematz, U.; Li, Ding Min; Simon, P.

    2000-01-01

    This work is an intercomparison of four tropospheric-stratospheric climate models, the Unified Model (UM) of the U.K. Meteorological Office (UKMO), the model of the Free University in Berlin (FUB). the ARPEGE-climat model of the National Center for Meteorological Research (CNRM), and the Extended UGAMP GCM (EUGCM) of the Center for Global Atmospheric Modelling (CGAM), against the UKMO analyses. This comparison has been made in the framework of the "GSM-Reality Intercomparison Project for SPARC" (GRIPS). SPARC (Stratospheric Processes and their Role in Climate) aims are to investigate the effects of the middle atmosphere on climate and the GRIPS purpose is to organized a comprehensive assessment of current Middle Atmosphere-Climate Models (MACMs). The models integrations were made without identical contraints e.g. boundary conditions, incoming solar radiation). All models are able to represent the dominant features of the extratropical circulation. In this paper, the structure of the tropical winds and the strengths of the Kelvin waves are examined. Explanations for the differences exhibited. between the models. as well as between models and analyses, are also proposed. In the analyses a rich spectrum of waves (eastward and westward) is present and contributes to drive the SAO (SemiAnnual Oscillation) and the QBO (Quasi-Biennal Oscillation). The amplitude of the Kelvin waves is close to the one observed in UARS (Upper Atmosphere Research Satellite) data. In agreement with observations, the Kelvin waves generated in the models propagate into the middle atmosphere as wave packets which underlines convective forcing origin. In most models, slow Kelvin waves propagate too high and are hence overestimated in the upper stratosphere and in the mesosphere, except for the UM which is more diffusive. These waves are not sufficient to force realistic westerlies of the QBO or SAO westerly phases. If the SAO is represented by all models only two of them are able to generate

  9. Comparative study of maximum isometric grip strength in different sports

    Directory of Open Access Journals (Sweden)

    Noé Gomes Borges Junior

    2009-06-01

    Full Text Available The objective of this study was to compare maximum isometric grip strength (Fmaxbetween different sports and between the dominant (FmaxD and non-dominant (FmaxND hand. Twenty-nine male aikido (AI, jiujitsu (JJ, judo (JU and rowing (RO athletes and 21non-athletes (NA participated in the study. The hand strength test consisted of maintainingmaximum isometric grip strength for 10 seconds using a hand dynamometer. The position of the subjects was that suggested by the American Society of Hand Therapy. Factorial 2X5 ANOVA with Bonferroni correction, followed by a paired t test and Tukey test, was used for statistical analysis. The highest Fmax values were observed for the JJ group when using the dominant hand,followed by the JU, RO, AI and NA groups. Variation in Fmax could be attributed to handdominance (30.9%, sports modality (39.9% and the interaction between hand dominance andsport (21.3%. The present results demonstrated significant differences in Fmax between the JJ and AI groups and between the JJ and NA groups for both the dominant and non-dominant hand. Significant differences in Fmax between the dominant and non-dominant hand were only observed in the AI and NA groups. The results indicate that Fmax can be used for comparisonbetween different sports modalities, and to identify differences between the dominant and nondominanthand. Studies involving a larger number of subjects will permit the identification of differences between other modalities.

  10. Grasping an augmented object to analyse manipulative force control.

    Science.gov (United States)

    Kawai, Satoru; Summers, Valerie A; Mackenzie, Christine L; Ivens, Chris J; Yamamoto, Takashi

    2002-12-15

    Augmented reality allows changes to be made to the visual perception of object size even while the tangible components remain completely unaltered. It was, therefore, utilized in a study whose results are being reported here to provide the proper environment required to thoroughly observe the exact effect that visual change to object size had on programming fingertip forces when objects were lifted with a precision grip. Twenty-one participants performed repeated lifts of an identical grip apparatus to a height of 20 mm, maintained each lift for 8 seconds, and then replaced the grip apparatus on the table. While all other factors of the grip apparatus remained unchanged, visual appearance was altered graphically in a 3-D augmented environment. The grip apparatus measured grip and load forces independently. Grip and load forces demonstrated significant rates of increase as well as peak forces as the size of graphical images increased; an aspect that occurred in spite of the fact that extraneous haptic information remained constant throughout the trials. By indicating a human tendency to rely - even unconsciously - on visual input to program the forces in the initial lifting phase, this finding provides further confirmation of previous research findings obtained in the physical environment; including the possibility of extraneous haptic effects (Gordon et al. 1991a, Mon-Williams and Murray 2000, Kawai et al. 2000). The present results also suggest that existing knowledge concerning human manipulation tasks in the physical world may be applied to an augmented environment where the physical objects are enhanced by computer generated visual components.

  11. Effects of grip width on muscle strength and activation in the lat pull-down.

    Science.gov (United States)

    Andersen, Vidar; Fimland, Marius S; Wiik, Espen; Skoglund, Anders; Saeterbakken, Atle H

    2014-04-01

    The lat pull-down is one of the most popular compound back exercises. Still, it is a general belief that a wider grip activates the latissimus dorsi more than a narrow one, but without any broad scientific support. The aim of the study was to compare 6 repetition maximum (6RM) load and electromyographic (EMG) activity in the lat pull-down using 3 different pronated grip widths. Fifteen men performed 6RM in the lat pull-down with narrow, medium, and wide grips (1, 1.5, and 2 times the biacromial distance) in a randomized and counterbalanced order. The 6RM strengths with narrow (80.3 ± 7.2 kg) and medium grip (80 ± 7.1 kg) were higher than wide grip (77.3 ± 6.3 kg; p = 0.02). There was similar EMG activation between grip widths for latissimus, trapezius, or infraspinatus, but a tendency for biceps brachii activation to be greater for medium vs. narrow (p = 0.09), when the entire movement was analyzed. Analyzing the concentric phase separately revealed greater biceps brachii activation using the medium vs. narrow grip (p = 0.03). In the eccentric phase, there was greater activation using wide vs. narrow grip for latissimus and infraspinatus (p ≤ 0.04), and tendencies for medium greater than narrow for latissimus, and medium greater than wide for biceps (both p = 0.08), was observed. Collectively, a medium grip may have some minor advantages over small and wide grips; however, athletes and others engaged in resistance training can generally expect similar muscle activation which in turn should result in similar hypertrophy gains with a grip width that is 1-2 times the biacromial distance.

  12. Comparative study of millennials' (age 20-34 years) grip and lateral pinch with the norms.

    Science.gov (United States)

    Fain, Elizabeth; Weatherford, Cara

    Cross-sectional research design. Clinical practice continues to use normative data for grip and pinch measurements that were established in 1985. There is no updated norms despite different hand usage patterns in today's society. Measuring and comparing grip and pinch strengths with normative data is a valid method to determine hand function. This research was implemented to compare the grip and pinch measurements obtained from healthy millennials to the established norms and to describe hand usage patterns for millennials. Grip and lateral pinch measurements were obtained from a sample of 237 healthy millennials (ages 20-34 years). Strength scores were statistically lower that older normative data in all millennial grip strengths, with the exception of the women in the age group of 30-34 years. Specifically, this statistically significant trend was observed in all male grip strengths, as well as in women in the age group of 20-24 years (bilateral grip) and 25-29 years (right grip). However, the lateral pinch data reflected was similar to the older norms with variances of 0.5-1 kg. Current data reflect statistically significant differences from the norms for all male grip measurements, as well as for women in the age group of 20-24 years (bilateral grip) and 25-29 years (right grip). No statistical significance was observed in the independent-sample t tests for the lateral pinch in men of all age groups. Statistical significance was noted for lateral pinch for female age groups for the left hand (20-24 years) and for bilateral lateral pinches (30-34 years). IV. Copyright © 2016 Hanley & Belfus. Published by Elsevier Inc. All rights reserved.

  13. Inverse Tasks In The Tsunami Problem: Nonlinear Regression With Inaccurate Input Data

    Science.gov (United States)

    Lavrentiev, M.; Shchemel, A.; Simonov, K.

    A variant of modified training functional that allows considering inaccurate input data is suggested. A limiting case when a part of input data is completely undefined, and, therefore, a problem of reconstruction of hidden parameters should be solved, is also considered. Some numerical experiments are presented. It is assumed that a dependence of known output variables on known input ones should be found is the classic problem definition, which is widely used in the majority of neural nets algorithms. The quality of approximation is evaluated as a performance function. Often the error of the task is evaluated as squared distance between known input data and predicted data multiplied by weighed coefficients. These coefficients may be named "precision coefficients". When inputs are not known exactly, natural generalization of performance function is adding member that responsible for distance between known inputs and shifted inputs, which lessen model's error. It is desirable that the set of variable parameters is compact for training to be con- verging. In the above problem it is possible to choose variants of demands of a priori compactness, which allow meaningful interpretation in the smoothness of the model dependence. Two kinds of regularization was used, first limited squares of coefficients responsible for nonlinearity and second limited multiplication of the above coeffi- cients and linear coefficients. Asymptotic universality of neural net ability to approxi- mate various smooth functions with any accuracy by increase of the number of tunable parameters is often the base for selecting a type of neural net approximation. It is pos- sible to show that used neural net will approach to Fourier integral transform, which approximate abilities are known, with increasing of the number of tunable parameters. In the limiting case, when input data is set with zero precision, the problem of recon- struction of hidden parameters with observed output data appears. The

  14. Bimanual Lifting: Do Fingertip Forces Work Independently or Interactively?

    Science.gov (United States)

    Dimitriou, Pan; Buckingham, Gavin

    2018-01-01

    Bimanual coordination is a commonplace activity, but the consequences of using both hands simultaneously are not well understood. The authors examined fingertip forces across 4 experiments in which participants undertook a range of bimanual tasks. They first measured fingertip forces during simultaneous lifts of 2 identical objects, noting that individuals held the objects with more force bimanually than unimanually. They then varied the mass of the objects held by each hand, noting that when both hands lifted together performance was equivalent to unimanual lifts. The authors next measured one hand's static grip force while the other hand lifted an object. They found a gradual reduction of grip force throughout the trial, but once again no evidence of one hand influencing the other. In the final experiment the authors tested whether tapping with one hand could influence the static grip force of its counterpart. Although the authors found no changes in static grip force as a direct consequence of the other hand's actions, they found clear differences from one task to the other, suggesting an effect of task instruction. Overall, these results suggest that fingertip forces are largely independent between hands in a bimanual lifting context, but are sensitive to different task requirements.

  15. The influence of target object shape on maximum grip aperture in human grasping movements

    NARCIS (Netherlands)

    Verheij, R.; Brenner, E.; Smeets, J.B.J.

    2014-01-01

    The shape of a target object could influence maximum grip aperture in human grasping movements in several different ways. Maximum grip aperture could be influenced by the required precision of digit placement, by the aim to avoid colliding with the wrong parts of the target objects, by the mass of

  16. Is grip strength a predictor for total muscle strength in healthy children, adolescents, and young adults?

    NARCIS (Netherlands)

    Wind, Anne E.; Takken, Tim; Helders, Paul J. M.; Engelbert, Raoul H. H.

    2010-01-01

    The primary purpose of this study was to examine whether grip strength is related to total muscle strength in children, adolescents, and young adults. The second purpose was to provide reference charts for grip strength, which could be used in the clinical and research setting. This cross-sectional

  17. The Effect of Dry Needling of the Trigger Points of Shoulder Muscles on Pain and Grip Strength in Patients with Lateral Epicondylitis: A Pilot Study

    Directory of Open Access Journals (Sweden)

    Alireza Kheradmandi

    2015-09-01

    Full Text Available Background: Lateral epicondylitis, also known as tennis elbow, is the most common overuse syndrome of the elbow. The severity of pain may not be directly caused by tendinopathy of wrist extensors since trigger points of the shoulder muscles have a referral zone in the arm and elbow. Therefore the aim of this study was to evaluate the effect of dry needling of shoulder myofascial trigger points on wrist extensors muscles pain and function. Methods: Fourteen female patients with tennis elbow (aged 20 - 45 years old were recruited after primary evaluation by an orthopedist. They entered the study if they had pain in the lateral aspect of elbow of the dominant hand for more than 3 months along with the presence of myofascial trigger points in any muscles of supra spinatus, infra spinatus, sub scapularis or scalenes. Pain pressure threshold, maximal grip force and pain intensity of the hand extensors on lateral epicondyle of elbow were measured before and after treatment. Pain intensity was measured on a one to ten scale of visual analogue scale (VAS. A hand dynamometer used to measure the maximal grip force value of the affected hand in 0˚shoulder flexion/ abduction, 90˚ elbow extension and mid-poison of forearm in sitting position. A pressure algometer was applied on hand extensor muscles to define their trigger point sensitivity. For the control group, treatment regimens consisted of routine physical therapy of tennis elbow. This regime was accompanied by dry needling of mentioned muscles for the intervention group. Wilcoxon and Mann-Whitney non-parametric tests were used for statistical analysis. Results: Comparison of the results after intervention showed that the patients’ pain significantly decreased in both groups (P<0.001; but the patient’s PPT and grip force significantly increased solely in the intervention group (P<0.05. Mann Whitney test showed significant pain differences in both groups (P=0.001. The comparison of differences

  18. Fuel assembly gripping device using self-locking mechanism

    International Nuclear Information System (INIS)

    Lee, G. M.; Choi, S.; Kim, K. S.; Kim, T. W.; Jeong, K. H.; Park, K. B.; Chang, M. H.

    1999-07-01

    This report presents an actuating principles and structure for two kind of the fuel assembly gripping devices (Gripper-A, B) developed for SMART. The main components of these grippers are push bundle, rotation bundle, upper guide tube and chuck assembly. The rope attached to winch system on moving cask hangs gripper's push bundle. Due to a down-and-up operation of winch system, the push bundle pushes crown teeth shaped rotation bundle and then it is pushed down and rotated counter clockwise. The push-and-pull sequential operation of push bundle makes the rotation bundle is pushed, rotated and returned, moreover it makes the chuck assembly is expanded or shrunk. The expansion and shrinkage motion of chuck assembly makes the gripper latch and release the fuel assembly. Gripper-A suits for the handling of the fuel assembly with square shaped latching hole. Otherwise Gripper-B suits for a circular shaped latching hole. (author). 5 refs., 20 figs

  19. NBL Pistol Grip Tool for Underwater Training of Astronauts

    Science.gov (United States)

    Liszka, Michael; Ashmore, Matthew; Behnke, Mark; Smith, Walter; Waterman, Tod

    2011-01-01

    A document discusses a lightweight, functional mockup of the Pistol Grip Tool for use during underwater astronaut training. Previous training tools have caused shoulder injuries. This new version is more than 50 percent lighter [in water, weight is 2.4 lb (=1.1 kg)], and can operate for a six-hour training session after 30 minutes of prep for submersion. Innovations in the design include the use of lightweight materials (aluminum and Delrin(Registered TradeMark)), creating a thinner housing, and the optimization of internal space with the removal of as much excess material as possible. This reduces tool weight and maximizes buoyancy. Another innovation for this tool is the application of a vacuum that seats the Orings in place and has shown to be reliable in allowing underwater usage for up to six hours.

  20. Comparative study of maximum isometric grip strength in different sports

    Directory of Open Access Journals (Sweden)

    Noé Gomes Borges Junior

    2009-01-01

    Full Text Available http://dx.doi.org/10.5007/1980-0037.2009v11n3p292   The objective of this study was to compare maximum isometric grip strength (Fmaxbetween different sports and between the dominant (FmaxD and non-dominant (FmaxND hand. Twenty-nine male aikido (AI, jiujitsu (JJ, judo (JU and rowing (RO athletes and 21non-athletes (NA participated in the study. The hand strength test consisted of maintainingmaximum isometric grip strength for 10 seconds using a hand dynamometer. The position of the subjects was that suggested by the American Society of Hand Therapy. Factorial 2X5 ANOVA with Bonferroni correction, followed by a paired t test and Tukey test, was used for statistical analysis. The highest Fmax values were observed for the JJ group when using the dominant hand,followed by the JU, RO, AI and NA groups. Variation in Fmax could be attributed to handdominance (30.9%, sports modality (39.9% and the interaction between hand dominance andsport (21.3%. The present results demonstrated significant differences in Fmax between the JJ and AI groups and between the JJ and NA groups for both the dominant and non-dominant hand. Significant differences in Fmax between the dominant and non-dominant hand were only observed in the AI and NA groups. The results indicate that Fmax can be used for comparisonbetween different sports modalities, and to identify differences between the dominant and nondominanthand. Studies involving a larger number of subjects will permit the identification of differences between other modalities.

  1. Effect of the Grip Angle on Off-Spin Bowling Performance Parameters, Analysed with a Smart Cricket Ball

    OpenAIRE

    Franz Konstantin Fuss; Batdelger Doljin; René E. D. Ferdinands

    2018-01-01

    In the off-spin bowling grip, the ball is clamped between index and middle fingers. Spin bowlers attempt to select a spread angle between these two fingers that achieves comfort and optimises performance. The aim of this paper was to investigate whether the standard grip is superior to narrow and wide grips. The bowling performance parameters were obtained from a smart cricket ball. Smart ball data revealed that the performance parameters varied with grip type. The following parameters were o...

  2. Hand grip endurance test relates to clinical state and prognosis in COPD patients better than 6-minute walk test distance

    Directory of Open Access Journals (Sweden)

    Kovarik M

    2017-12-01

    Full Text Available Miroslav Kovarik,1,2 Vera Joskova,1,2 Anna Patkova,1,2 Vladimir Koblizek,3 Zdenek Zadak,2 Miloslav Hronek1,2 1Department of Biological and Medical Sciences, Faculty of Pharmacy in Hradec Kralove, Charles University, Hradec Kralove, Czech Republic; 2Department of Research and Development, University Hospital Hradec Kralove, Hradec Kralove, Czech Republic; 3Department of Pulmonary Medicine, University Hospital Hradec Kralove, Hradec Kralove, Czech Republic Purpose: Patients with COPD present peripheral muscle dysfunction and atrophy, expressed as muscle strength and endurance reduction. The goal of this study was direct dynamometric assessment of hand grip endurance and strength in relation to the stage of disease, multidimensional predictors of mortality, and 6-minute walk test (6MWT. To the best of our knowledge, there has been no previous study determining these parameters.Patients and methods: In this observational study, 58 consecutive outpatients with stable COPD and 25 volunteers without respiratory problems were compared. All COPD subjects underwent a comprehensive examination to determine COPD severity, prognostic scales, and 6MWT. Body composition, basic spirometric parameters, and hand grip strength and endurance were determined in all study participants.Results: Patients in the COPD group had a 15% decrease in maximum strength (P=0.012 and a 28% decrease in area under the force/time curve (AUC of the endurance test (P<0.001 compared to the control group. Dynamometric parameters were significantly negatively associated with the stage of disease and values of multivariable prediction indexes, and positively associated with the results of 6MWT. In most cases, closer associations were found with AUC than with 6MWT and in the gender-specific groups.Conclusion: Both hand grip strength and endurance are impaired in COPD patients in comparison with the control group. In particular, AUC could be considered as an attractive option not only to

  3. Hypo- and hypernatremia results in inaccurate erythrocyte mean corpuscular volume measurement in vitro, when using Sysmex XE 2100

    DEFF Research Database (Denmark)

    Phillipsen, Jens Peter; Madsen, Kirsten Vikkelsø

    2015-01-01

    INTRODUCTION: Automated hematology analyzers dilute patient erythrocytes with an isoosmotic diluent before quantitating the erythrocyte mean cell volume (MCV). However, if patient plasma osmolality differs from the diluent, water will cross the erythrocytes membrane and establish a new equilibrium...... resulted in inaccurate MCV. The experimental results also revealed a strong correlation between P-Osmolality/P-Sodium and MCV inaccuracy (R2 = 0.70/0.85) similar to the theoretically calculated MCV inaccuracy. We suggest using mean cellular Hb (MCH) instead of MCV, mean corpuscular Hb concentration (MCHC...

  4. Effects of kinesio tape compared with non-elastic tape on hand grip strength.

    Science.gov (United States)

    Kim, Ji Young; Kim, Seong Yeol

    2016-05-01

    [Purpose] Many assumptions have been made about taping and several studies have considered tape application methods; however, the true effect of taping on muscle strength remains unclear. Most previous studies compared application techniques using Kinesio tape (KT), but studies that compared muscle strength using non-elastic tape (NT) are limited. Moreover, no studies have applied KT and NT in the same way to assess grip strength in normal subjects. The purpose of this study was to evaluate the immediate effect of application of two tapes with different elastic properties on maximal grip strength in healthy adults. [Subjects and Methods] Twenty healthy adults were divided into two groups (KT and NT). Maximal grip strength was measured with a dynamometer. Forearm extensor muscles of the dominant hand were then taped and subjects were immediately asked to perform hand grip movement with maximum strength in the same standardized manner. [Results] In the KT group, maximal grip strength was significantly increased compared to the initial value; however, in the NT group, there was no significant difference in maximal grip strength. [Conclusion] This study suggests that only Kinesio tape can increase maximal grip strength immediately after application on the extensor region of the forearm.

  5. Superiority of the dominant and nondominant hands in static strength and controlled force exertion.

    Science.gov (United States)

    Noguchi, Takanori; Demura, Shinichi; Aoki, Hiroki

    2009-10-01

    The dominant hand can be defined in such a way that Oldfield's Handedness Inventory may not identify the superior hand, i.e., the hand with more strength and/or more force control. The dominant and nondominant hands were compared for two different grip force-exertion tests. 50 healthy young men (M age = 21.1 yr.) performed two tests with each hand: a maximal grip strength test and a controlled force-exertion test with dynamic demand. In the latter test, the participants matched their submaximal grip force to the changing demand values with real-time feedback. The total sum of the differences between the demand value and grip force value for 25 sec. was used as an evaluation parameter for the test (unit: %). Mean maximal grip force values in the right and left hands were 439.9 N (SD = 59.1) and 405.6 N (SD = 59.3), respectively. Mean controlled force-exertion test values in the right and left hands were 610.3% (SD = 150.2) and 722.6% (SD = 147.8), respectively. In both tests, the dominant hand was significantly stronger and controlled dynamic force better. The relationship between the two hands was very high. Based on this study's criteria, the dominant hand was stronger in 34% (n = 17) of participants during the maximal grip strength test and more controlled in 54% (n = 27) of participants during the controlled force-exertion test. Thus, the dynamic force control test showed that for significantly more people the dominant hand is stronger and controls force better. Controlled force exertion may be a better test for identifying the superior hand.

  6. Interpersonal and intrapersonal variance of exponent of power function observed in grip strength task.

    Science.gov (United States)

    Kokubun, M; Okuzumi, H; Koike, T; Haishi, K; Suzuki, H

    2001-08-01

    For grip strength there is a power function with an exponent of 1.7 between the subjective magnitude and the actual force exerted by a subject, but large variabilities among and within individuals were found. We focused on these variabilities and investigated the relationship between them by conducting a ratio production procedure requiring trials of maximum effort and half of maximum effort. For 30 adults we conducted four measurement trials, two on the same day, and the remaining two trials on a day or two later. The mean value of the exponent, the standard deviation, and the coefficient of variation of the four trials for each subject were calculated. The mean value of the exponent of the power function for all subjects was 1.6. This value approximated the value of 1.7 reported by Stevens and Mack. The values ranged from .50 to 5.39. The correlation between subjects' mean exponent value and standard deviation was .90, and the correlation between the mean value of the exponent and the coefficient of variation was .50. There was a close relationship between interpersonal and intrapersonal variance.

  7. Outcomes of single-stage grip-release reconstruction in tetraplegia.

    Science.gov (United States)

    Reinholdt, Carina; Fridén, Jan

    2013-06-01

    To evaluate the outcomes of our technique for single-stage grip-release reconstruction and compare it with previous 1- and 2-stage grip reconstructions in tetraplegia. A total of 14 patients (16 hands) with tetraplegia underwent a single-stage combination of operations to provide pinch, grip, and release function. We compared the study group with a historical control group of 15 patients (18 hands) who had been treated with staged flexion-extension grip-release reconstructions. Both groups were classified as ocular cutaneous 4. Assessment parameters included grip and pinch strength, maximal opening of the first webspace, and Canadian Occupational Performance Measurement. Both groups were rehabilitated with early active mobilization beginning the first day after surgery. Grip strength and opening of the first webspace were significantly greater in the single-stage group than in the comparative group. Pinch strength was not significantly different between groups. On the Canadian Occupational Performance Measurement score, patients belonging to the single-stage group were highly satisfied (increase of 3.7 points) and could perform several of their self-selected goals (3.5 points of improvement). The single-stage grip-release reconstruction provides people who have spinal cord injuries and tetraplegia with improved and reliable grip function; active finger flexion, active thumb flexion, passive thumb extension, and passive interossei function can all be achieved through this procedure. Early active mobilization is particularly important in improving functional outcome after this combination of grip reconstruction procedures. Therapeutic III. Copyright © 2013 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  8. Immediate and Delayed Effects of Forearm Kinesio Taping on Grip Strength

    Science.gov (United States)

    Kouhzad Mohammadi, Hosein; Khademi Kalantari, Khosro; Naeimi, Sedighe Sadat; Pouretezad, Mohammad; Shokri, Esmaeil; Tafazoli, Mojdeh; Dastjerdi, Mahboobeh; Kardooni, Leila

    2014-01-01

    Background: Due to the fundamental role of gripping in most upper limb activities, grip strength promotion is a chief goal in the treatment of patients with upper limb musculoskeletal disorders. Kinesio taping is a novel and effective therapeutic technique believed to facilitate muscle contraction through stimulating mechanoreceptors and increasing the sensory feedback around the taped region. Objectives: The present study aimed to identify the best region (flexor, extensor and flexor/extensor regions) and time (immediate, 0.5, 1, 1.5, and 2 hours) of forearm Kinesio taping to obtain the maximum improvement in grip strength. Materials and Methods: In this longitudinal study, 40 healthy men and women (the mean age of 22.3 ± 2.19 years) were selected among students of Shahid Beheshti University of Medical Sciences, Tehran, Iran by simple, nonrandom sampling method. A dynamometer was used to measure grip strength immediately and every 30 minutes during the two hours after I-shaped application of tape (with 50% stretch) to the flexor, extensor, and flexor/extensor forearm muscles. Results: Grip strength was significantly increased in various muscle groups for males (P = 0.002) and females (P = 0.000) of the forearm and at different intervals for males (P = 0.000) and females (P = 0.000). Moreover, in both men and women, tape application to the extensor region provided greater grip strength compared to taping of the flexor and flexor/extensor regions (P = 0.000 for both). Furthermore, the maximum increase in grip strength were 0.5 (10.8% increase, P = 0.001) and 1.5 h (23.9% increase, P = 0.000) after taping in males and females, respectively. Conclusions: Taping the extensor region of forearm is recommended to achieve higher grip strength. Although grip strength increased at a slower pace in females than males, the final values were higher in women. PMID:25389492

  9. Immediate and delayed effects of forearm kinesio taping on grip strength.

    Science.gov (United States)

    Kouhzad Mohammadi, Hosein; Khademi Kalantari, Khosro; Naeimi, Sedighe Sadat; Pouretezad, Mohammad; Shokri, Esmaeil; Tafazoli, Mojdeh; Dastjerdi, Mahboobeh; Kardooni, Leila

    2014-08-01

    Due to the fundamental role of gripping in most upper limb activities, grip strength promotion is a chief goal in the treatment of patients with upper limb musculoskeletal disorders. Kinesio taping is a novel and effective therapeutic technique believed to facilitate muscle contraction through stimulating mechanoreceptors and increasing the sensory feedback around the taped region. The present study aimed to identify the best region (flexor, extensor and flexor/extensor regions) and time (immediate, 0.5, 1, 1.5, and 2 hours) of forearm Kinesio taping to obtain the maximum improvement in grip strength. In this longitudinal study, 40 healthy men and women (the mean age of 22.3 ± 2.19 years) were selected among students of Shahid Beheshti University of Medical Sciences, Tehran, Iran by simple, nonrandom sampling method. A dynamometer was used to measure grip strength immediately and every 30 minutes during the two hours after I-shaped application of tape (with 50% stretch) to the flexor, extensor, and flexor/extensor forearm muscles. Grip strength was significantly increased in various muscle groups for males (P = 0.002) and females (P = 0.000) of the forearm and at different intervals for males (P = 0.000) and females (P = 0.000). Moreover, in both men and women, tape application to the extensor region provided greater grip strength compared to taping of the flexor and flexor/extensor regions (P = 0.000 for both). Furthermore, the maximum increase in grip strength were 0.5 (10.8% increase, P = 0.001) and 1.5 h (23.9% increase, P = 0.000) after taping in males and females, respectively. Taping the extensor region of forearm is recommended to achieve higher grip strength. Although grip strength increased at a slower pace in females than males, the final values were higher in women.

  10. Effect of the Grip Angle on Off-Spin Bowling Performance Parameters, Analysed with a Smart Cricket Ball

    Directory of Open Access Journals (Sweden)

    Franz Konstantin Fuss

    2018-02-01

    Full Text Available In the off-spin bowling grip, the ball is clamped between index and middle fingers. Spin bowlers attempt to select a spread angle between these two fingers that achieves comfort and optimises performance. The aim of this paper was to investigate whether the standard grip is superior to narrow and wide grips. The bowling performance parameters were obtained from a smart cricket ball. Smart ball data revealed that the performance parameters varied with grip type. The following parameters were optimum at the standard grip: spin rate, resultant torque, spin torque, peak angular acceleration, and peak power. The following parameters were optimum at standard and wide grips: efficiency. The following parameters were optimum at standard and narrow grips: pitch angle of spin axis. The following parameters were optimum at the wide grip: precession and the precession torque. In general, the data tended to show that the standard grip is most effective for spin bowling. However, more research is needed to confirm this result, because the precession and precession torque were optimum at the wide grip, suggesting that this may have a superior performance over the standard and narrow grips.

  11. Fuel assembly gripping device using self-locking mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Lee, G. M.; Choi, S.; Kim, K. S.; Kim, T. W.; Jeong, K. H.; Park, K. B.; Chang, M. H

    1999-07-01

    This report presents an actuating principles and structure for two kind of the fuel assembly gripping devices (Gripper-A, B) developed for SMART. The main components of these grippers are push bundle, rotation bundle, upper guide tube and chuck assembly. The rope attached to winch system on moving cask hangs gripper's push bundle. Due to a down-and-up operation of winch system, the push bundle pushes crown teeth shaped rotation bundle and then it is pushed down and rotated counter clockwise. The push-and-pull sequential operation of push bundle makes the rotation bundle is pushed, rotated and returned, moreover it makes the chuck assembly is expanded or shrunk. The expansion and shrinkage motion of chuck assembly makes the gripper latch and release the fuel assembly. Gripper-A suits for the handling of the fuel assembly with square shaped latching hole. Otherwise Gripper-B suits for a circular shaped latching hole. (author). 5 refs., 20 figs.

  12. Characterization of corticospinal activation of finger motor neurons during precision and power grip in humans

    DEFF Research Database (Denmark)

    Svane, Christian; Forman, Christian Riis; Nielsen, Jens Bo

    2018-01-01

    Direct and indirect corticospinal pathways to finger muscles may play a different role in control of the upper extremity. We used transcranial magnetic stimulation (TMS) and coherence analysis to characterize the corticospinal drive to the first dorsal interosseous (FDI) and abductor pollicis bre...... brevis (APB) when active during a precision and power grip task. In experiment 1, single motor units were recorded during precision grip and power grip in 20 adults (25.2 ± 7.1 years). Post-stimulus time histograms (PSTH) were obtained following TMS. In experiment 2, coherence and cross...... system) is equally involved in the control of both tasks. The data do not support that indirect pathways would make a larger contribution to power grip....

  13. GRIP NOAA GLOBAL HAWK IN-FLIGHT TURBULENCE SENSOR (GHIS) V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GRIP NOAA Global Hawk In-Flight Turbulence Sensor (GHIS) dataset was collected by the NOAA Global Hawk In-flight Turbulence Sensor (GHIS) instrument, which...

  14. A Monte Carlo-tuned model of the flow in the NorthGRIP area

    DEFF Research Database (Denmark)

    Grinsted, Aslak; Dahl-Jensen, Dorthe

    2002-01-01

    The North Greenland Icecore Project (NorthGRIP) drill site was chosen in order to obtain a good Eemian record. At the present depth, 3001m, the Eemian interstadial has yet to be seen. Clearly the flow in this area is poorly understood and needs further investigation. After a review of specific...... no Eemian is observed is a high basal melt rate (2.7mm/a). The melting is a consequence of a higher geothermal heat flux than the expected 51mW/m^2 of the Precambrian shield. From our analyses it is concluded that the geothermal heat flux at NorthGRIP is 98mW/m^2.The high basalmelt rate also gives rise...... to sliding at the bed. In addition to these results, an accumulationmodel has been established specifically forNorthGRIP.These results are essential for further modelling of the NorthGRIP flow and depth-age relationship...

  15. Effect of Putting Grip on Eye and Head Movements During the Golf Putting Stroke

    Directory of Open Access Journals (Sweden)

    George K. Hung

    2003-01-01

    Full Text Available The objective of this article is to determine the effect of three different putting grips (conventional, cross-hand, and one-handed on variations in eye and head movements during the putting stroke. Seven volunteer novice players, ranging in age from 21 to 22 years, participated in the study. During each experimental session, the subject stood on a specially designed platform covered with artificial turf and putted golf balls towards a standard golf hole. The three different types of grips were tested at two distances: 3 and 9 ft. For each condition, 20 putts were attempted. For each putt, data were recorded over a 3-s interval at a sampling rate of 100 Hz. Eye movements were recorded using a helmet-mounted eye movement monitor. Head rotation about an imaginary axis through the top of the head and its center-of-rotation was measured by means of a potentiometer mounted on a fixed frame and coupled to the helmet. Putter-head motion was measured using a linear array of infrared phototransistors embedded in the platform. The standard deviation (STD, relative to the initial level was calculated for eye and head movements over the duration of the putt (i.e., from the beginning of the backstroke, through the forward stroke, to impact. The averaged STD for the attempted putts was calculated for each subject. Then, the averaged STDs and other data for the seven subjects were statistically compared across the three grip conditions. The STD of eye movements were greater (p < 0.1 for conventional than cross-hand (9 ft and one-handed (3 and 9 ft grips. Also, the STD of head movements were greater (p < 0.1; 3 ft for conventional than cross-hand and one-handed grips. Vestibulo-ocular responses associated with head rotations could be observed in many 9 ft and some 3 ft putts. The duration of the putt was significantly longer (p < 0.05; 3 and 9 ft for the one-handed than conventional and cross-hand grips. Finally, performance, or percentage putts made, was

  16. Effect of putting grip on eye and head movements during the golf putting stroke.

    Science.gov (United States)

    Hung, George K

    2003-03-24

    The objective of this article is to determine the effect of three different putting grips (conventional, cross-hand, and one-handed) on variations in eye and head movements during the putting stroke. Seven volunteer novice players, ranging in age from 21 to 22 years, participated in the study. During each experimental session, the subject stood on a specially designed platform covered with artificial turf and putted golf balls towards a standard golf hole. The three different types of grips were tested at two distances: 3 and 9 ft. For each condition, 20 putts were attempted. For each putt, data were recorded over a 3-s interval at a sampling rate of 100 Hz. Eye movements were recorded using a helmet-mounted eye movement monitor. Head rotation about an imaginary axis through the top of the head and its center-of-rotation was measured by means of a potentiometer mounted on a fixed frame and coupled to the helmet. Putter-head motion was measured using a linear array of infrared phototransistors embedded in the platform. The standard deviation (STD, relative to the initial level) was calculated for eye and head movements over the duration of the putt (i.e., from the beginning of the backstroke, through the forward stroke, to impact). The averaged STD for the attempted putts was calculated for each subject. Then, the averaged STDs and other data for the seven subjects were statistically compared across the three grip conditions. The STD of eye movements were greater (p < 0.1) for conventional than cross-hand (9 ft) and one-handed (3 and 9 ft) grips. Also, the STD of head movements were greater (p < 0.1; 3 ft) for conventional than cross-hand and one-handed grips. Vestibulo-ocular responses associated with head rotations could be observed in many 9 ft and some 3 ft putts. The duration of the putt was significantly longer (p < 0.05; 3 and 9 ft) for the one-handed than conventional and cross-hand grips. Finally, performance, or percentage putts made, was significantly

  17. Effects of Fat Grip Training on Muscular Strength and Driving Performance in Division I Male Golfers.

    Science.gov (United States)

    Cummings, Patrick M; Waldman, Hunter S; Krings, Ben M; Smith, JohnEric W; McAllister, Matthew J

    2018-01-01

    Cummings, PM, Waldman, HS, Krings, BM, Smith, JW, and McAllister, MJ. Effects of fat grip training on muscular strength and driving performance in division I male golfers. J Strength Cond Res 32(1): 205-210, 2018-Fat grip (FG) training is implemented into strength and conditioning programs with the overall goal of increasing grip strength. Previous research assessing the effect of training with increased grip diameters compared with standard Olympic bar diameters has mainly been in acute settings. Therefore, the purpose of this study was to examine to effects FG training compared with normal diameter grip (CON) training during an 8-week periodized resistance training (RT) program in division I male golfers. Subjects (n = 10) were randomly assigned into 2 groups: the FG group (n = 5, scoring average: 75.4 ± 2.0) and CON group (n = 5, scoring average: 75.0 ± 0.5). Both groups participated in 8 weeks of RT (3 d·wk). The FG group completed every lift and repetition using FG, compared with the CON training group which used normal diameter bars. Pretraining and posttraining performance variables included swing speed, ball speed, driving distance, driving carry, maximum pull-ups to failure, right and left hand grip strength, and 1 repetition max trap-bar deadlift. The FG group demonstrated significant increases (p ≤ 0.05) in ball speed, carry, drive distance, and left hand grip strength after 8 weeks of RT. In a population, such as low-handicap division I male golfers, FG training may allow for athletes to increase golf-specific performance after 8 weeks of periodized RT. Strength and conditioning coaches may use FG training over the course of a training program with athletes who require adequate grip strength to further elicit training adaptations.

  18. Grip strength in mice with joint inflammation: A rheumatology function test sensitive to pain and analgesia.

    Science.gov (United States)

    Montilla-García, Ángeles; Tejada, Miguel Á; Perazzoli, Gloria; Entrena, José M; Portillo-Salido, Enrique; Fernández-Segura, Eduardo; Cañizares, Francisco J; Cobos, Enrique J

    2017-10-01

    Grip strength deficit is a measure of pain-induced functional disability in rheumatic disease. We tested whether this parameter and tactile allodynia, the standard pain measure in preclinical studies, show parallels in their response to analgesics and basic mechanisms. Mice with periarticular injections of complete Freund's adjuvant (CFA) in the ankles showed periarticular immune infiltration and synovial membrane alterations, together with pronounced grip strength deficits and tactile allodynia measured with von Frey hairs. However, inflammation-induced tactile allodynia lasted longer than grip strength alterations, and therefore did not drive the functional deficits. Oral administration of the opioid drugs oxycodone (1-8 mg/kg) and tramadol (10-80 mg/kg) induced a better recovery of grip strength than acetaminophen (40-320 mg/kg) or the nonsteroidal antiinflammatory drugs ibuprofen (10-80 mg/kg) or celecoxib (40-160 mg/kg); these results are consistent with their analgesic efficacy in humans. Functional impairment was generally a more sensitive indicator of drug-induced analgesia than tactile allodynia, as drug doses that attenuated grip strength deficits showed little or no effect on von Frey thresholds. Finally, ruthenium red (a nonselective TRP antagonist) or the in vivo ablation of TRPV1-expressing neurons with resiniferatoxin abolished tactile allodynia without altering grip strength deficits, indicating that the neurobiology of tactile allodynia and grip strength deficits differ. In conclusion, grip strength deficits are due to a distinct type of pain that reflects an important aspect of the human pain experience, and therefore merits further exploration in preclinical studies to improve the translation of new analgesics from bench to bedside. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  19. Improvement of handle grip using reverse engineering, CAE and Rapid Prototyping

    Directory of Open Access Journals (Sweden)

    Stoklasek Pavel

    2016-01-01

    Full Text Available The overwhelming majority of manual operations is even nowadays performed by using manual hand tools. These tools can be divided into 2 groups – hand tools designed for general use or a single-purpose hand tools for special operations. Tool described in this paper is used in assembling operation in the completion of electric motor. During the design of the existing tools the requirements for a functional part of the tool (lifespan, inability to damage the engine installation were fully considered, demands for ergonomic grip area, however, were not taken into account. Long-term use of incorrectly designed tool causes carpal tunnel syndrome, hand-arm vibration syndrome, diminished sensitivity or tingling in the fingers of workers. These difficulties can be reduced or entirely eliminated due to proper design of the grip of hand tool. Most authors focus on adjusting the grip for optimum ergonomics at individual types of grips (cylindrical, palmar, lateral, etc.. However, as already mentioned, there are tools for specific operations when the working area is limited by space or a specific type of load on the grip is needed. In some cases, it is often necessary to change the type of grip or combine different types of grips. This paper describes the design of an optimal grip of hand tool used for specific operation when assembling motors. Design of prototype mold and production of functional prototypes for ergonomics assessment directly in the workplace were realized. New design of handle should reduce the risk primarily of developing carpal tunnel in long-term use.

  20. Regulation of grasping forces during bimanual in-phase and anti-phase coordination.

    Science.gov (United States)

    Serrien, D J; Wiesendanger, M

    2001-01-01

    When a hand-held object is moved, grip force is adapted in an anticipatory manner to load force due to a dynamic coupling between both forces. The present study addressed the issue of grip-load force regulation when moving rhythmically two hand-held objects in the vertical dimension, and more specifically the divergence of force control when performing according to the in-phase versus anti-phase mode. Results revealed that grip-load force ratio profiles were similar in both bimanual conditions. That is, force ratio was not constant throughout the movement cycles but followed a fairly regular pattern with maxima and minima, attained at upward and downward hand positions, respectively. However, anti-phase patterns showed an increased maximum grip-load force ratio as compared to in-phase patterns, whereas the latter did not differ from unimanual movements. The magnification of maximum force ratio during anti-phase movements suggests that rescaling occurred. This is likely due to the complexity of the anti-phase mode that necessitates increased monitoring and attention relative to the other performance conditions, creating a coordinative situation that imposes an additional degree of uncertainty. Therefore, the safety margin is amplified during anti-phase movements, probably as a strategy to prevent a potential destabilization of the grip during an asymmetrical load condition. Accordingly, these findings also demonstrate that grip-load force regulation is more proficiently controlled during bimanual in-phase than anti-phase movements. Herewith, the data add content to earlier work illustrating kinematic dissimilarities between both coordination modes.

  1. Does Grip Strength Reflect Isokinetic Muscle Strength in Lower Limbs in Patients with CIDP?

    Science.gov (United States)

    Knak, Kirsten L; Andersen, Linda K; Christiansen, Ingelise; Markvardsen, Lars K

    2018-03-30

    Introduction Grip strength is a common measure of general muscle strength in patients with chronic inflammatory demyelinating polyneuropathy (CIDP). However, it is important to investigate the correlation and responsiveness of grip strength compared to isokinetic muscle strength (IKS) and function of the lower limbs. Methods Seventy patients with CIDP were evaluated with grip strength, IKS and functional measures of the lower limbs. Reevaluation was done after 2 and 10/12 weeks. Correlation and response analyses were performed. Results Grip strength correlated with IKS ankle (maximum Spearman's rank correlation (R S ) = 0.58) and with walking performance (maximum R S = -0.38). IKS ankle was more responsive to detect change (Standardized Response Mean (SRM) = 0.57) than grip strength (SRM = 0.27). Discussion Grip strength does not seem to be an appropriate surrogate measure of IKS and function of the lower limbs in patients with CIDP. This article is protected by copyright. All rights reserved. © 2018 Wiley Periodicals, Inc.

  2. Hold, grasp, clutch or grab: consumer grip choices during food container opening.

    Science.gov (United States)

    Rowson, J; Yoxall, A

    2011-07-01

    Society is ageing and sadly that ageing leads to a host of issues, not least a society in which the majority are likely to have some loss of strength and dexterity. This can lead to complications in undertaking everyday tasks such as using transport, bathing or even handling and opening food. Packaging has to provide a multitude of services; to protect and preserve the product, to provide information to the consumer and not least to allow access to the contents. This access to packaging--or 'openability'--has become a significant issue for designers and manufacturers with the change in demographics as described above. Understanding the choices consumers make in how they manipulate packaging can help designers produce packaging that is more able to meet the requirements of modern society. Studies previously undertaken by the authors showed that consumers did use different grips when opening packaging and that certain grips were theoretically more comfortable and stronger than others. This paper outlines a further study whereby consumers were asked to apply the most common grips to a specially designed torque measuring device. Details were taken about the consumers: age, gender, occupation, hand size, plus their preferred grip choice for packaging of this type. The study showed that typically women chose a grip that maximised their opportunity of opening the closure and that this grip choice was more limited than that available for men. This has implications for inclusive design of many everyday products. Copyright © 2010 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  3. Heritability of slow and/or inaccurate reading ability in 33,000 adult twins with self-reported data

    DEFF Research Database (Denmark)

    Fibiger-Dagnæs, Steen; von Bornemann Hjelmborg, Jacob; Erbs, Lena

    2012-01-01

    Genetic influence for adult slow and/or inaccurate reading ability was studied from selfreported answers, using a dichotomous question on having difficulties in reading the Danish subtitles on foreign TV programs. The data from 33,424 twins were population based and were used for biometric analysis...... in order to estimate the heritability of reading difficulties. The rate of reading difficulties were 6–9 percent, higher for males than females. Tetrachoric correlations were estimated under univariate saturated models, specified with appropriate constraints. Hierarchical x2 tests showed that the fit...... demonstrates substantial genetic, almost only additive, influence on reading difficulties. The environmental factors affecting reading difficulties were unique and unshared (E). Unshared environmental factors are those factors that are specific to an individual, thus contributing to differences between family...

  4. Learning to produce predicted static handgrip forces.

    Science.gov (United States)

    Angyán, L; Téczely, T; Karsai, I

    2005-01-01

    The objective of this study was to prove the hypothesis that kinaesthetic sensations, without visual or verbal guidance, give sufficient information to produce predictive handgrip forces. The ability of 70 girls and 70 boys aged 11 to 17 years to produce predicted static handgrip force was examined. The subjects were requested to produce 50% of their individual maximum handgrip force and maintain it for 2 seconds without visual control. Ten trials were done first by the right-hand and then by the left-hand. The maximum grip strength increased parallel with age, but significant differences were found between both the right and the left-hand, and the genders. Close correlations were found between the desired and the exerted forces. The differences between the desired forces and the exerted forces produced by the fifth trials were significantly smaller than that of the first trials. The verbal information about each exerted force contributed to the learning with right-hand since it caused a further decrease in the difference between the desired force and the exerted force. In contrast, the learning with left-hand was not enhanced by verbal feedback. These results suggest that kinaesthetic feedback information from the hand plays an effective role in learning to produce predicted grip strengths without visual and verbal information.

  5. Inaccurate weight perception is associated with extreme weight-management practices in U.S. high school students.

    Science.gov (United States)

    Ibrahim, Chadi; El-Kamary, Samer S; Bailey, Jason; St George, Diane M

    2014-03-01

    The objective of the present study was to examine whether adolescents' weight perception accuracy (WPA) was associated with extreme weight-management practices (EWPs) in differing body mass index (BMI) categories. WPA, overassessment, and underassessment were determined by comparing self-reported BMI and weight perception among U.S. high school students in the 2009 National Youth Risk Behavior Survey. BMI was classified as follows: underweight (perception were discordant. Overassessors thought they were heavier than they were (among underweight/healthy groups); underassessors thought they were lighter than they were (among healthy/overweight/obese groups). EWPs included ≥1 of fasting, use of diet pills, or purging/laxative use. Logit models were fitted for different BMI sex strata. In the final sample of 14,722 US high school students with complete data, 20.2%, 85.7%, 5.8%, and 80.9% of those who were underweight, healthy weight, overweight, and obese, inaccurately assessed their weight, respectively. In turn, 11.4% and 17.6% of accurate and inaccurate assessors engaged in EWPs, respectively. After adjustment, underweight girls who overassessed their weight had 12.6 times higher odds of EWPs (95% confidence interval 3.4-46.6). Moreover, there were elevated odds of EWPs among healthy weight students who overassessed their weight. Overassessing healthy weight students and underweight girls had higher odds of ≥1 EWPs, likely related to an unhealthy desire to lose weight. The present study demonstrates a need to further educate clinicians on WPA and its relation to EWPs even among those of healthy weight who may be seen as not at risk.

  6. Adapting haptic guidance authority based on user grip

    NARCIS (Netherlands)

    Smisek, J.; Mugge, W.; Smeets, J.B.J.; Van Paassen, M.M.; Schiele, A

    2014-01-01

    Haptic guidance systems support the operator in task execution using additional forces on the input device. Scaling of the guidance forces determines the control authority of the support system. As task complexity may vary, one level of the guidance scaling may be insufficient, and adaptation of the

  7. Genetic influences on the development of grip strength in adolescence.

    Science.gov (United States)

    Isen, Joshua; McGue, Matt; Iacono, William

    2014-06-01

    Enhanced physical strength is a secondary sex characteristic in males. Sexual dimorphism in physical strength far exceeds sex differences in stature or total body mass, suggesting a legacy of intense sexual selection. Upper-body strength is a particularly promising marker of intrasexual competitiveness in young men. Consequently, it is assumed that sex-influenced gene expression contributes to the development of physical strength. It is unclear, however, whether the underlying sources of individual differences in strength development are comparable across sex. We obtained three measurements of hand-grip strength (HGS) over a six-year period spanning adolescence in male and female same-sex twins (N = 2,513). Biometrical latent growth models were used to partition the HGS variance at age 11 (intercept) and its growth over time (slope) into genetic and environmental components. Results demonstrated that variance around the intercept was highly heritable in both males and females (88% and 79%, respectively). In males, variance around the slope exceeded that of the intercept, while the reverse held for females. Additive genetic effects accounted for most (80%) of the variance around the slope in males, but were of less importance in females (heritability = 28%). Absolute genetic variance around the slope was nearly nine-fold higher in males. This striking disparity suggests that the developmental processes shaping HGS growth are different between the sexes. We propose that this might account for the sex-specific pattern of associations between HGS and external measures (e.g., digit ratio and physical aggression) typically reported in the literature. Our results underscore the role of endogenous androgenic influences in the development of physical strength. © 2014 Wiley Periodicals, Inc.

  8. Force-directed design of a voluntary closing hand prosthesis

    NARCIS (Netherlands)

    De Visser, H.; Herder, J.L.

    2000-01-01

    This paper presents the design of a body-powered voluntary closing prosthetic hand. It is argued that the movement of the fingers before establishing a grip is much less relevant for good control of the object held than the distribution of forces once the object has been contacted. Based on this

  9. Determining Sincerity of Effort Based on Grip Strength Test in Three Wrist Positions

    Directory of Open Access Journals (Sweden)

    Petcharatana Bhuanantanondh

    2018-03-01

    Full Text Available Background: Several grip strength tests are commonly used for detecting sincerity of effort. However, there is still no widely accepted standardized sincerity of effort test. Therefore, this study aimed to examine whether grip strength test in three wrist positions could distinguish between maximal and submaximal efforts. Methods: Twenty healthy individuals (10 men and 10 women with a mean age of 26.7 ± 3.92 years participated in this study. All participants completed two test conditions (maximal and submaximal efforts in three wrist positions (neutral, flexion, and extension using both hands. Each participant exerted 100% effort in the maximal effort condition and 50% effort in the submaximal effort condition. The participants performed three repetitions of the grip strength test for each session. Results: The results showed that there is a significant main effect of the type of effort (p < 0.001, wrist position (p < 0.001, and hand (p = 0.028. There were also significant types of effort and wrist position interactions (p < 0.001 and effort and hand interactions (p < 0.028. The results also showed that grip strength was highest at the wrist in neutral position in both the maximal and the submaximal effort condition. Grip strength values of the three wrist positions in the maximal effort condition were noticeably greater than those in the submaximal effort condition. Conclusion: The findings of this study suggest that grip strength test in three wrist positions can differentiate a maximal effort from a submaximal effort. Thus, this test could potentially be used to detect sincerity of effort in clinical setting. Keywords: grip strength, maximal effort, sincerity of effort, submaximal effort, wrist position

  10. Clinical effectiveness of grip strength in predicting ambulation of elderly inpatients

    Directory of Open Access Journals (Sweden)

    Beseler MR

    2014-11-01

    Full Text Available MR Beseler,1 C Rubio,1 E Duarte,1 D Hervás,2 MC Guevara,1 M Giner-Pascual,1 E Viosca1 1Physical Medicine and Rehabilitation, La Fe Hospital, Valencia, Spain; 2Statistical Unit, La Fe Hospital, Valencia, Spain Background: Assessing the clinical effectiveness of measuring grip strength as a prognostic tool in recovering ambulation in bed-confined frail elderly patients. Methods: A prospective study was carried out with 50 elderly inpatients (mean age: 81.6 years old. Manual muscle test was used for checking strength of hip flexor muscles, hip abductor muscles and knee extensor muscles. Grip strength was assessed by hydraulic dynamometer. Walking ability was assessed by functional ambulation categories and Functional Classification of Sagunto Hospital Ambulation. Existence of cognitive impairment (Short Portable Mental Status of Pfeiffer and comorbidity (abbreviated Charlson index were considered to be confounding variables. Statistical analysis: Simple comparisons and mixed models of multiple ordinal regression. Results: The sample presented generalized weakness in scapular (mean 4.22 and pelvic (mean 3.82 muscle. Mean hand grip values were similar: 11.98 kg right hand; 11.70 kg left hand. The patients had lost walking ability. After treatment, there was a statistically significant for scapular waist strength (P=0.001, pelvic waist strength (P=0.005 and walking ability (P=0.001. A statistically significant relationship in the regression analysis was found between the grip (right and left hands and walking ability post-treatment (P=0.009; odds ratio 1.14 and P=0.0014 odds ratio 1.113 for each walking scale. The confounding variables showed no statistical significance in the results.Conclusion: Grip strength is associated with walking ability in hospitalized frail elderly. Grip strength assessment by hydraulic dynamometry is useful in patients with poor collaboration. Walking ability training in frail elderly inpatients is useful. Keywords: gait

  11. Efeito da preensão manual sobre o equilíbrio de judocas Effect of hand grip on the balance of judokas

    Directory of Open Access Journals (Sweden)

    Jonathan Ache Dias

    2011-06-01

    Full Text Available O objetivo deste estudo foi verificar se existe efeito da preensão manual máxima (o ato de realizar ou não a preensão sobre o controle do equilíbrio de judocas em postura restrita, além de verificar se existe correlação entre a força de preensão manual (FPM e o controle do equilíbrio. Foram avaliados sete judocas com um dinamômetro e uma plataforma estabilométrica sendo mensuradas, concomitantemente, a FPM e o centro de pressão (CP. Foi verificado que até 80% da variabilidade do CP pode ser atrelada a preensão manual indicando que a mesma gera perturbações no controle do equilíbrio. Entretanto, foram encontradas correlações (r = 0,348 até 0,816 entre a FPM e o deslocamento do CP. Com isso pode-se concluir que, apesar da preensão manual gerar perturbações no equilíbrio, seu comportamento parece estar relacionado com os movimentos do corpo realizados para manter o equilíbrio, indicando uma possível correlação entre esses fenômenos.The purpose of this study was to verify if there is an effect of maximum hand grip (the act of performing or not the hand grip on the balance control of judokas in a restrict posture, and also to verify if there is a correlation between the hand grip strength (HGS and the balance control. Seven judokas were evaluated with a dynamometer and a stabilometric force platform, being measured, at the same time, the HGS and the center of pressure (COP. It was found that up to 80% of the COP variability was related to the hand grip demonstrating that it generates perturbations to the balance control. However, It was found correlations (r = 0,348 to 0,816 between de HGS and de COP displacement. With that, it can be concluded that, despite the hand grip generating perturbation on the balance, its behavior appears to be related to the body movements performed to sustain balance, indicating a possible correlation between this phenomenons.

  12. Age trajectories of grip strength: cross-sectional and longitudinal data among 8,342 Danes aged 46 to 102

    DEFF Research Database (Denmark)

    Frederiksen, Henrik; Hjelmborg, Jacob; Mortensen, Jakob

    2006-01-01

    PURPOSE: The purpose is to study the age trajectory of hand-grip strength after the age of 45 years. METHODS: In this study, we use data from three large nationwide population-based surveys of Danes aged 45 to 102 years with a total of 8342 participants with grip-strength measurements and up to 4...... years of follow-up. Grip strength was measured by using a portable hand dynamometer. RESULTS: Grip strength declines throughout life for both males and females, but among the oldest women, the longitudinal curve reaches a horizontal plateau. The course of the decline is estimated by using full...... with increasing age. Estimates were obtained by using full-information methods from large population-representative studies. Equations of expected grip strength, as well as tables with sex-, age-, and height-stratified reference data, provide an opportunity to include grip-strength measurement in clinical care...

  13. Large-scale GWAS identifies multiple loci for hand grip strength providing biological insights into muscular fitness

    DEFF Research Database (Denmark)

    Willems, Sara M; Wright, Daniel J; Day, Felix R

    2017-01-01

    ,180 individuals and identify 16 loci associated with grip strength (Pmaintenance and signal transduction (PEX14, TGFA, SYT1), or monogenic syndromes...... with involvement of psychomotor impairment (PEX14, LRPPRC and KANSL1). Mendelian randomization analyses are consistent with a causal effect of higher genetically predicted grip strength on lower fracture risk. In conclusion, our findings provide new biological insight into the mechanistic underpinnings of grip...

  14. SU-E-T-377: Inaccurate Positioning Might Introduce Significant MapCheck Calibration Error in Flatten Filter Free Beams

    International Nuclear Information System (INIS)

    Wang, S; Chao, C; Chang, J

    2014-01-01

    Purpose: This study investigates the calibration error of detector sensitivity for MapCheck due to inaccurate positioning of the device, which is not taken into account by the current commercial iterative calibration algorithm. We hypothesize the calibration is more vulnerable to the positioning error for the flatten filter free (FFF) beams than the conventional flatten filter flattened beams. Methods: MapCheck2 was calibrated with 10MV conventional and FFF beams, with careful alignment and with 1cm positioning error during calibration, respectively. Open fields of 37cmx37cm were delivered to gauge the impact of resultant calibration errors. The local calibration error was modeled as a detector independent multiplication factor, with which propagation error was estimated with positioning error from 1mm to 1cm. The calibrated sensitivities, without positioning error, were compared between the conventional and FFF beams to evaluate the dependence on the beam type. Results: The 1cm positioning error leads to 0.39% and 5.24% local calibration error in the conventional and FFF beams respectively. After propagating to the edges of MapCheck, the calibration errors become 6.5% and 57.7%, respectively. The propagation error increases almost linearly with respect to the positioning error. The difference of sensitivities between the conventional and FFF beams was small (0.11 ± 0.49%). Conclusion: The results demonstrate that the positioning error is not handled by the current commercial calibration algorithm of MapCheck. Particularly, the calibration errors for the FFF beams are ~9 times greater than those for the conventional beams with identical positioning error, and a small 1mm positioning error might lead to up to 8% calibration error. Since the sensitivities are only slightly dependent of the beam type and the conventional beam is less affected by the positioning error, it is advisable to cross-check the sensitivities between the conventional and FFF beams to detect

  15. Relationship between grip, pinch strengths and anthropometric variables, types of pitch throwing among Japanese high school baseball pitchers.

    Science.gov (United States)

    Tajika, Tsuyoshi; Kobayashi, Tsutomu; Yamamoto, Atsushi; Shitara, Hitoshi; Ichinose, Tsuyoshi; Shimoyama, Daisuke; Okura, Chisa; Kanazawa, Saeko; Nagai, Ayako; Takagishi, Kenji

    2015-03-01

    Grip and pinch strength are crucially important attributes and standard parameters related to the functional integrity of the hand. It seems significant to investigate normative data for grip and pinch strength of baseball players to evaluate their performance and condition. Nevertheless, few reports have explained the association between grip and pinch strength and anthropometric variables and types of pitch throwing for baseball pitchers. The aim of this study was to measure and evaluate clinical normative data for grip and tip, key, palmar pinch strength and to assess the relationship between these data and anthropometric variables and types of pitch throwing among Japanese high-school baseball pitchers. One hundred-thirty three healthy high school baseball pitchers were examined and had completed a self-administered questionnaire including items related to age, hand dominance, throwing ratio of type of pitch. A digital dynamometer was used to measure grip strength and a pinch gauge to measure tip, key and palmer pinch in both dominant and nondominant side. Body composition was measured by the multi frequency segmental body composition analyzer. Grip strength and tip and palmer pinch strength in dominant side were statistically greater than them in nondominant side (P strength and height (r = 0.33, P strength were predictors of grip strength in dominant side. No statistical significant correlations were found between the throwing ratio of types of pitches thrown and grip strength and tip, key, palmar pinch strength. Our result provides normative values and evidences for grip and pinch strengths in high school baseball pitchers.

  16. Sex Differences in Fear of Falling among Older Adults with Low Grip Strength.

    Science.gov (United States)

    Lim, Eunju

    2016-05-01

    Fear of falling is not only a risk factor for falls, but it is also an important clinical predictor of functional decline in older adults. This study identified sex differences in fear of falling and related factors in older adults with low grip strength. The data of 902 older adults from the 2012 Korean National Survey, conducted as a research project by the Korea Employment Information Service, were analyzed. Grip strength, activities of daily living, cognitive function, depressive symptoms, and fear of falling were assessed. Multiple regression analysis was performed by a simultaneous data entry method. Fear of falling was greater in older women with low grip strength than in their male equivalents (Pfall experience within the previous 2 yr, activities of daily living, and depressive symptoms collectively accounted for 15.3% (Pfall experience within the previous 2 yr, grip strength, activities of daily living, and depressive symptoms collectively accounted for 13.4% (Pfalling differ between older men and women with low grip strength. Therefore, sex differences must be considered when developing intervention strategies for reducing fear of falling in this demographic.

  17. E-GRIP: A Highly Elliptical Orbit Satellite Mission for Co-location in Space

    Science.gov (United States)

    Männel, Benjamin; Rothacher, Markus; Jetzer, Philippe; Lecomte, Steve; Rochat, Pascal

    2016-12-01

    The Einstein Gravitational Red-shift Probe (E-GRIP) will be a new satellite mission allowing detailed studies for relativistic and geodetic purposes. The scientific objectives of E-GRIP are the measurement of the space-time curvature around the Earth, multiple tests of general relativity, and special geodetic applications. E-GRIP will fly in a highly eccentric orbit (e>0.6, apogee > 35000 km) and will carry a narrow- and a wide-angle microwave link (at both X- and K-band), two GNSS antennas, SLR retro-reflectors, a photon counter unit, and a space hydrogen maser. Consequently, E-GRIP could act as a co-location satellite with suitable observation conditions for VLBI. Beyond a mission overview, we provide results from extended VLBI simulations concerning link budget, visibilities, and achievable station coordinate results. In addition, we present also some basic considerations concerning the feasibility of co-located GNSS and SLR observations for E-GRIP's highly elliptical orbit.

  18. Jamar hand-held grip dynamometry in chronic inflammatory demyelinating polyneuropathy.

    Science.gov (United States)

    Rajabally, Yusuf A; Narasimhan, Manisha

    2013-02-15

    Few studies have evaluated the functional and electrophysiological correlates of hand-held grip dynamometry in neuromuscular disease. The practical value of normative values remains uncertain in clinical practice. We aimed to ascertain the value, clinical and electrophysiological correlates, as well as utility of normative values for grip dynamometry, in a cohort of subjects with chronic inflammatory demyelinating polyneuropathy (CIDP). We performed a cross-sectional study of 31 prospectively recruited subjects with CIDP, using Jamar hand-held grip dynamometry, conventional clinical assessments and electrophysiology. Grip dynamometry correlated highly with motor, sensory and functional scores in the upper limbs as well as with global function. There were significant correlations with summated median/ulnar, and ulnar compound muscle action potentials. Patients' readings were significantly lower than median normative values but comparable to fifth percentile normative figures. Jamar grip dynamometry is a reliable measure of global neurological status in patients with CIDP, not limited to upper limb or exclusively motor function. At optimum level of function, CIDP patients had comparable dynamometry recordings to fifth percentile normative values, which may represent a realistic aim for treated subjects with the disorder, with currently available therapies. Crown Copyright © 2012. Published by Elsevier B.V. All rights reserved.

  19. In meta-analyses of proportion studies, funnel plots were found to be an inaccurate method of assessing publication bias.

    Science.gov (United States)

    Hunter, James P; Saratzis, Athanasios; Sutton, Alex J; Boucher, Rebecca H; Sayers, Robert D; Bown, Matthew J

    2014-08-01

    To assess the utility of funnel plots in assessing publication bias (PB) in meta-analyses of proportion studies. Meta-analysis simulation study and meta-analysis of published literature reporting peri-operative mortality after abdominal aortic aneurysm (AAA) repair. Data for the simulation study were stochastically generated. A literature search of Medline and Embase was performed to identify studies for inclusion in the published literature meta-analyses. The simulation study demonstrated that conventionally constructed funnel plots (log odds vs. 1/standard error [1/SE]) for extreme proportional outcomes were asymmetric despite no PB. Alternative funnel plots constructed using study size rather than 1/SE showed no asymmetry for extreme proportional outcomes. When used in meta-analyses of the mortality of AAA repair, these alternative funnel plots highlighted the possibility for conventional funnel plots to demonstrate asymmetry when there was no evidence of PB. Conventional funnel plots used to assess for potential PB in meta-analyses are inaccurate for meta-analyses of proportion studies with low proportion outcomes. Funnel plots of study size against log odds may be a more accurate way of assessing for PB in these studies. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Sample Size Calculation: Inaccurate A Priori Assumptions for Nuisance Parameters Can Greatly Affect the Power of a Randomized Controlled Trial.

    Directory of Open Access Journals (Sweden)

    Elsa Tavernier

    Full Text Available We aimed to examine the extent to which inaccurate assumptions for nuisance parameters used to calculate sample size can affect the power of a randomized controlled trial (RCT. In a simulation study, we separately considered an RCT with continuous, dichotomous or time-to-event outcomes, with associated nuisance parameters of standard deviation, success rate in the control group and survival rate in the control group at some time point, respectively. For each type of outcome, we calculated a required sample size N for a hypothesized treatment effect, an assumed nuisance parameter and a nominal power of 80%. We then assumed a nuisance parameter associated with a relative error at the design stage. For each type of outcome, we randomly drew 10,000 relative errors of the associated nuisance parameter (from empirical distributions derived from a previously published review. Then, retro-fitting the sample size formula, we derived, for the pre-calculated sample size N, the real power of the RCT, taking into account the relative error for the nuisance parameter. In total, 23%, 0% and 18% of RCTs with continuous, binary and time-to-event outcomes, respectively, were underpowered (i.e., the real power was 90%. Even with proper calculation of sample size, a substantial number of trials are underpowered or overpowered because of imprecise knowledge of nuisance parameters. Such findings raise questions about how sample size for RCTs should be determined.

  1. The SAO and Kelvin waves in the EuroGRIPS GCMS and the UK Met. Office analyses

    Directory of Open Access Journals (Sweden)

    M. Amodei

    2001-01-01

    Full Text Available We compare the tropical oscillations and planetary scale Kelvin waves in four troposphere-stratosphere climate models and the assimilated dataset produced by the United Kingdom Meteorological Office (UKMO. The comparison has been made in the GRIPS framework "GCM-Reality Intercomparison Project for SPARC", where SPARC is Stratospheric Processes and their Role in Climate, a project of the World Climate Research Program. The four models evaluated are European members of GRIPS: the UKMO Unified Model (UM, the model of the Free University in Berlin (FUB–GCM, the ARPEGE-climat model of the French National Centre for Meteorological Research (CNRM, and the Extended UGAMP GCM (EUGCM of the Centre for Global Atmospheric Modelling (CGAM. The integrations were performed with different, but annually periodic external conditions (e.g., sea-surface temperature, sea ice, and incoming solar radiation. The structure of the tropical winds and the strengths of the Kelvin waves are examined. In the analyses where the SAO (Semi-Annual Oscillation and the QBO (Quasi-Biennal Oscillation are reasonably well captured, the amplitude of these analysed Kelvin waves is close to that observed in independent data from UARS (Upper Atmosphere Research Satellite. In agreement with observations, the Kelvin waves generated in the models propagate into the middle atmosphere as wave packets, consistent with a convective forcing origin. In three of the models, slow Kelvin waves propagate too high and their amplitudes are overestimated in the upper stratosphere and in the mesosphere, the exception is the UM which has weaker waves. None of the modelled waves are sufficient to force realistic eastward phases of the QBO or SAO. Although the SAO is represented by all models, only two of them are able to generate westerlies between 10 hPa and 50 hPa. The importance of the role played in the SAO by unresolved gravity waves is emphasized. Although it exhibits some unrealistic features, the

  2. An investigation of maximal hand grip strength related to body mass index in healthy Czech children

    Directory of Open Access Journals (Sweden)

    Martin Šteffl

    2016-12-01

    Full Text Available Hand grip strength is one of the most important markers in muscle strength assessment for many reasons. However, its maximal value in kilograms is highly dependent on body size, which may misrepresent results, especially among children. Therefore, correction by body mass index (BMI can be used as a suitable approach for its objectification. The aims of this study were to create reference values for the grip to BMI ratio and for hand grip strength for children in the Czech Republic. 554 children of both genders, aged from 4 to 14 years, were included in the current study. Reference values were approximated by Tukey’s Hinges percentiles calculation method. The percentile charts were created using the Lambda-Mu-Sigma (LMS method.

  3. Hand grip function assessed by the box and block test is affected by object surfaces.

    Science.gov (United States)

    Seo, Na Jin; Enders, Leah R

    2012-01-01

    N/A. One of the hand function assessment tools is the Box and Block Test (BBT). To examine if the BBT score is affected by grip surfaces. Thirteen adults performed the BBT with wooden, rubber-covered, and paper-covered blocks. The BBT scores and time for seven movements (finger closing, contact to lift-off, transport before barrier, transport after barrier, release, return, and reach) were compared across the three block types. The mean BBT score was 8% higher for the rubber blocks than the paper and wooden blocks (pblock until the block is lifted). Hand function assessments should be controlled for object surfaces. Therapists may vary grip difficulties by changing object surfaces. Redesigning daily objects with high-friction surfaces may increase grip function. N/A. Copyright © 2012 Hanley & Belfus. Published by Elsevier Inc. All rights reserved.

  4. Two cases of firearm grip impressions on the hands of suicide victims.

    Science.gov (United States)

    Poulos, Christopher K; Peterson, Brian L

    2012-03-01

    Many factors are used to help distinguish firearm suicides from homicides and accidents, including range of fire, location of entrance defects, wound path trajectory, backspatter (blowback), and gunshot residue. Specifically, authors have discussed examination of the hands for backspatter, gunshot residue, cylinder gap effects, iron staining, and trauma as means of supporting a person having held a firearm while committing suicide. Here, we discuss 2 cases where suicidal gunshot wounds were accompanied by unique firearm grip impressions on the hands of the decedents. In 1 case, a "negative"[ impression of a grip pattern was left in a decedent's hand and in another case a grip pattern was left on the decedent's hand in dried blood. Such impressions can be used to provide support for establishing suicide as the manner of death.

  5. Effect of Low-Level Laser Therapy and Strength Training Protocol on Hand Grip by Dynamometry.

    Science.gov (United States)

    Barbosa, Rafael; Marcolino, Alexandre; Souza, Vitor; Bertolino, Guilherme; Fonseca, Marisa; Guirro, Rinaldo

    2017-01-01

    Introduction: The purpose of this study was to investigate the effect of low-level laser therapy (LLLT) - 660 nm and 904 nm - before grip strength protocol in healthy subjects. Methods: The study included 45 healthy volunteers with an average age of 22.7 (±1.4) years, subdivided into the following groups, control group: grip strength training associated with placebo LLLT; 660 nm group: LLLT (660 nm, 20 J/cm 2 , power of 30 mW, and beam area of 0.06 cm 2 , continuous, energy 1.2 J, and exposure time 40 seconds per point) before grip strength training and 904 nm group: LLLT (904 nm, 10 J/cm 2 , peak power of 70 W and 0.13 cm 2 beam area, with pulsed beam 9.500 Hz and 30 seconds of exposure time per point and emitted energy 1.2 J) before grip strength training. The LLLT was timed to contact 10 points located in the region of the superficial and deep flexor muscles of the fingers, with a total energy of 12.0 J per session. For the strength training protocol, the volunteer exercised their fingers with the dominant hand on a small table, elbow flexed at 90°, forearm in neutral, using a light extension handle. The Oxford protocol was performed during four weeks. The grip strength was assessed using a dynamometer (Jamar™). The data were evaluated by the analysis of variance (ANOVA) statistical method. Results: In the comparison of intragroup evaluation, only the 904 nm group showed a difference compared to the baseline assessment after 4 weeks ( P < 0.05), in the final intergroup evaluation, a difference was observed in the comparison between the control and 904 nm groups Conclusion: In conclusion, LLLT (904 nm) applied before resistance training was effective in gaining grip strength when compared to LLLT (660 nm) and isolated strength training after 4 weeks.

  6. Direct observation of salts as micro-inclusions in the Greenland GRIP ice core

    DEFF Research Database (Denmark)

    Dahl-Jensen, Dorthe; Sakurai, Toshimitsu; Iizuka, Yoshinori

    2009-01-01

    We provide the first direct evidence that a number of water-soluble compounds, in particular calcium sulfate (CaSO4·2H2O) and calcium carbonate (CaCO3), are present as solid, micron-sized inclusions within the Greenland GRIP ice core. The compounds are detected by two independent methods: micro...... distributions of the micro-inclusions. These results suggest that water-soluble aerosols in the GRIP ice core are dependable proxies for past atmospheric conditions. Udgivelsesdato: December...

  7. Grip and detachment of locusts on inverted sandpaper substrates

    International Nuclear Information System (INIS)

    Han Longbao; Wang Zhouyi; Ji Aihong; Dai Zhendong

    2011-01-01

    Locusts (Locusta migratoria manilensis) are characterized by their strong flying and grasping ability. Research on the grasping mechanism and behaviour of locusts on sloping substrates plays an important role in elucidating the mechanics of hexapod locomotion. Data on the maximum angles of slope at which locusts can grasp stably (critical angles of detachment) were obtained from high-speed video recordings at 215 fps. The grasping forces were collected by using two sensors, in situations where all left legs were standing on one and the right legs on the other sensor plate. These data were used to illustrate the grasping ability of locusts on slopes with varying levels of roughness. The grasping morphologies of locusts' bodies and tarsi were observed, and the surface roughness as well as diameters of their claw tips was measured under a microscope to account for the grasping mechanism of these insects on the sloping substrate. The results showed that the claw tips and part of the pads were in contact with the inverted substrate when the mean particle diameter was in the range of 15.3-40.5 μm. The interaction between pads and substrates may improve the stability of contact, and claw tips may play a key role in keeping the attachment reliable. A model was developed to explain the significant effects of the relative size of claw tips and mean particle diameter on grasping ability as well as the observed increase in lateral force (2.09-4.05 times greater than the normal force during detachment) with increasing slope angle, which indicates that the lateral force may be extremely important in keeping the contact reliable. This research lays the groundwork for the probable design and development of biomimetic robotics.

  8. Grip and detachment of locusts on inverted sandpaper substrates

    Energy Technology Data Exchange (ETDEWEB)

    Han Longbao; Wang Zhouyi; Ji Aihong; Dai Zhendong, E-mail: zddai@nuaa.edu.cn [Institute of Bio-inspired Structure and Surface Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China)

    2011-12-15

    Locusts (Locusta migratoria manilensis) are characterized by their strong flying and grasping ability. Research on the grasping mechanism and behaviour of locusts on sloping substrates plays an important role in elucidating the mechanics of hexapod locomotion. Data on the maximum angles of slope at which locusts can grasp stably (critical angles of detachment) were obtained from high-speed video recordings at 215 fps. The grasping forces were collected by using two sensors, in situations where all left legs were standing on one and the right legs on the other sensor plate. These data were used to illustrate the grasping ability of locusts on slopes with varying levels of roughness. The grasping morphologies of locusts' bodies and tarsi were observed, and the surface roughness as well as diameters of their claw tips was measured under a microscope to account for the grasping mechanism of these insects on the sloping substrate. The results showed that the claw tips and part of the pads were in contact with the inverted substrate when the mean particle diameter was in the range of 15.3-40.5 {mu}m. The interaction between pads and substrates may improve the stability of contact, and claw tips may play a key role in keeping the attachment reliable. A model was developed to explain the significant effects of the relative size of claw tips and mean particle diameter on grasping ability as well as the observed increase in lateral force (2.09-4.05 times greater than the normal force during detachment) with increasing slope angle, which indicates that the lateral force may be extremely important in keeping the contact reliable. This research lays the groundwork for the probable design and development of biomimetic robotics.

  9. An Alternative Flight Software Trigger Paradigm: Applying Multivariate Logistic Regression to Sense Trigger Conditions Using Inaccurate or Scarce Information

    Science.gov (United States)

    Smith, Kelly M.; Gay, Robert S.; Stachowiak, Susan J.

    2013-01-01

    In late 2014, NASA will fly the Orion capsule on a Delta IV-Heavy rocket for the Exploration Flight Test-1 (EFT-1) mission. For EFT-1, the Orion capsule will be flying with a new GPS receiver and new navigation software. Given the experimental nature of the flight, the flight software must be robust to the loss of GPS measurements. Once the high-speed entry is complete, the drogue parachutes must be deployed within the proper conditions to stabilize the vehicle prior to deploying the main parachutes. When GPS is available in nominal operations, the vehicle will deploy the drogue parachutes based on an altitude trigger. However, when GPS is unavailable, the navigated altitude errors become excessively large, driving the need for a backup barometric altimeter to improve altitude knowledge. In order to increase overall robustness, the vehicle also has an alternate method of triggering the parachute deployment sequence based on planet-relative velocity if both the GPS and the barometric altimeter fail. However, this backup trigger results in large altitude errors relative to the targeted altitude. Motivated by this challenge, this paper demonstrates how logistic regression may be employed to semi-automatically generate robust triggers based on statistical analysis. Logistic regression is used as a ground processor pre-flight to develop a statistical classifier. The classifier would then be implemented in flight software and executed in real-time. This technique offers improved performance even in the face of highly inaccurate measurements. Although the logistic regression-based trigger approach will not be implemented within EFT-1 flight software, the methodology can be carried forward for future missions and vehicles.

  10. An Alternative Flight Software Paradigm: Applying Multivariate Logistic Regression to Sense Trigger Conditions using Inaccurate or Scarce Information

    Science.gov (United States)

    Smith, Kelly; Gay, Robert; Stachowiak, Susan

    2013-01-01

    In late 2014, NASA will fly the Orion capsule on a Delta IV-Heavy rocket for the Exploration Flight Test-1 (EFT-1) mission. For EFT-1, the Orion capsule will be flying with a new GPS receiver and new navigation software. Given the experimental nature of the flight, the flight software must be robust to the loss of GPS measurements. Once the high-speed entry is complete, the drogue parachutes must be deployed within the proper conditions to stabilize the vehicle prior to deploying the main parachutes. When GPS is available in nominal operations, the vehicle will deploy the drogue parachutes based on an altitude trigger. However, when GPS is unavailable, the navigated altitude errors become excessively large, driving the need for a backup barometric altimeter to improve altitude knowledge. In order to increase overall robustness, the vehicle also has an alternate method of triggering the parachute deployment sequence based on planet-relative velocity if both the GPS and the barometric altimeter fail. However, this backup trigger results in large altitude errors relative to the targeted altitude. Motivated by this challenge, this paper demonstrates how logistic regression may be employed to semi-automatically generate robust triggers based on statistical analysis. Logistic regression is used as a ground processor pre-flight to develop a statistical classifier. The classifier would then be implemented in flight software and executed in real-time. This technique offers improved performance even in the face of highly inaccurate measurements. Although the logistic regression-based trigger approach will not be implemented within EFT-1 flight software, the methodology can be carried forward for future missions and vehicles

  11. Large-scale GWAS identifies multiple loci for hand grip strength providing biological insights into muscular fitness

    DEFF Research Database (Denmark)

    Willems, Sara M; Wright, Daniel J.; Day, Felix R

    2017-01-01

    with involvement of psychomotor impairment (PEX14, LRPPRC and KANSL1). Mendelian randomization analyses are consistent with a causal effect of higher genetically predicted grip strength on lower fracture risk. In conclusion, our findings provide new biological insight into the mechanistic underpinnings of grip...

  12. Grip strength and lower limb extension power in 19-72-year-old Danish men and women

    DEFF Research Database (Denmark)

    Aadahl, Mette; Beyer, Nina; Linneberg, Allan

    2011-01-01

    To assess muscular fitness by hand grip strength (HGS) and lower limb extension power (LEP) and to explore associations with age, leisure time physical activity (LTPA) and body composition.......To assess muscular fitness by hand grip strength (HGS) and lower limb extension power (LEP) and to explore associations with age, leisure time physical activity (LTPA) and body composition....

  13. Large-scale GWAS identifies multiple loci for hand grip strength providing biological insights into muscular fitness

    NARCIS (Netherlands)

    Willems, Sara M.; Wright, D.J.; Day, Felix R.; Trajanoska, Katerina; Joshi, P.K.; Morris, John A.; Matteini, Amy M.; Garton, Fleur C.; Grarup, Niels; Oskolkov, Nikolay; Thalamuthu, Anbupalam; Mangino, Massimo; Liu, Jun; Demirkan, Ayse; Lek, Monkol; Xu, Liwen; Wang, Guan; Oldmeadow, Christopher; Gaulton, Kyle J.; Lotta, Luca A.; Miyamoto-Mikami, Eri; Rivas, Manuel A.; White, Tom; Loh, Po Ru; Aadahl, Mette; Amin, Najaf; Attia, John R.; Austin, Krista; Benyamin, Beben; Brage, Søren; Cheng, Yu Ching; Ciȩszczyk, Paweł; Derave, Wim; Eriksson, Karl Fredrik; Eynon, Nir; Linneberg, Allan; Lucia, Alejandro; Massidda, Myosotis; Mitchell, Braxton D.; Miyachi, Motohiko; Murakami, Haruka; Padmanabhan, Sandosh; Pandey, Ashutosh; Papadimitriou, Ioannis; Rajpal, Deepak K.; Sale, Craig; Schnurr, Theresia M.; Sessa, Francesco; Shrine, Nick; Tobin, Martin D.; Varley, Ian; Wain, Louise V.; Wray, Naomi R.; Lindgren, Cecilia M.; MacArthur, Daniel G.; Waterworth, Dawn M.; McCarthy, Mark I.; Pedersen, Oluf; Khaw, Kay Tee; Kiel, Douglas P.; Pitsiladis, Yannis; Fuku, Noriyuki; Franks, Paul W.; North, Kathryn N.; Duijn, Van C.M.; Mather, Karen A.; Hansen, Torben; Hansson, Ola; Spector, Tim D.; Murabito, Joanne M.; Richards, J.B.; Rivadeneira, Fernando; Langenberg, Claudia; Perry, John R.B.; Wareham, Nick J.; Scott, Robert A.; Oei, Ling; Zheng, Hou Feng; Forgetta, Vincenzo; Leong, Aaron; Ahmad, Omar S.; Laurin, Charles; Mokry, Lauren E.; Ross, Stephanie; Elks, Cathy E.; Bowden, Jack; Warrington, Nicole M.; Murray, Anna; Ruth, Katherine S.; Tsilidis, Konstantinos K.; Medina-Gómez, Carolina; Estrada, Karol; Bis, Joshua C.; Chasman, Daniel I.; Demissie, Serkalem; Enneman, Anke W.; Hsu, Yi Hsiang; Ingvarsson, Thorvaldur; Kähönen, Mika; Kammerer, Candace; Lacroix, Andrea Z.; Li, Guo; Liu, Ching Ti; Liu, Yongmei; Lorentzon, Mattias; Mägi, Reedik; Mihailov, Evelin; Milani, Lili; Moayyeri, Alireza; Nielson, Carrie M.; Sham, Pack Chung; Siggeirsdotir, Kristin; Sigurdsson, Gunnar; Stefansson, Kari; Trompet, Stella; Thorleifsson, Gudmar; Vandenput, Liesbeth; Velde, Van Der Nathalie; Viikari, Jorma; Xiao, Su Mei; Zhao, Jing Hua; Evans, Daniel S.; Cummings, Steven R.; Cauley, Jane; Duncan, Emma L.; Groot, De Lisette C.P.G.M.; Esko, Tonu; Gudnason, Vilmundar; Harris, Tamara B.; Jackson, Rebecca D.; Jukema, J.W.; Ikram, Arfan M.A.; Karasik, David; Kaptoge, Stephen; Kung, Annie Wai Chee; Lehtimäki, Terho; Lyytikäinen, Leo Pekka; Lips, Paul; Luben, Robert; Metspalu, Andres; Meurs, van Joyce B.; Minster, Ryan L.; Orwoll, Erick; Oei, Edwin; Psaty, Bruce M.; Raitakari, Olli T.; Ralston, Stuart W.; Ridker, Paul M.; Robbins, John A.; Smith, Albert V.; Styrkarsdottir, Unnur; Tranah, Gregory J.; Thorstensdottir, Unnur; Uitterlinden, Andre G.; Zmuda, Joseph; Zillikens, M.C.; Ntzani, Evangelia E.; Evangelou, Evangelos; Ioannidis, John P.A.; Evans, David M.; Ohlsson, Claes

    2017-01-01

    Hand grip strength is a widely used proxy of muscular fitness, a marker of frailty, and predictor of a range of morbidities and all-cause mortality. To investigate the genetic determinants of variation in grip strength, we perform a large-scale genetic discovery analysis in a combined sample of

  14. EFFECT OF ECCENTRIC EXERCISE PROGRAMME ON PAIN AND GRIP STRENGTH FOR SUBJECTS WITH MEDIAL EPICONDYLITIS

    Directory of Open Access Journals (Sweden)

    Mishra Prashant Akhilesh

    2014-04-01

    Full Text Available Background and Objective: Therapeutic eccentric exercise may provide both a structural and functional benefit during tendinopathy rehabilitation. The objective is to find the effect of eccentric exercises on improvement of pain and grip strength for subjects with Medial Epicondylitis. Method: Pre to post test experimental study design randomized thirty subjects with medial epicondylitis, 15 each into Group A and Group B. Group B subjects were treated with conventional therapy and Eccentric exercises. Group A subjects were treated with conventional therapy. Results: When means of post intervention were compared using Independent ‘t’ between groups there was no statistically significant difference in improvements obtained in VAS scores and grip strength. There was a statistically significant change in means of VAS score and Grip strength when means were analyzed by using Paired‘t’ test and Wilcoxon signed rank test within the groups with positive percentage of change. Conclusion: It is concluded that four weeks of Eccentric Exercise Programme combined with conventional therapy shown significant effect on improving pain and Grip strength, however the improvement obtained has no difference when compared with control conventional treatment for Subjects with Medial Epicondylitis.

  15. The Effects of Unit Exercises on the Hand Grip Strength of Arm Wrestlers

    Science.gov (United States)

    Yonca, Sezer S.; Engin, Çelikel B.; Serdar, Yücel A.; Mustafa, Karadag; Yüksel, Savucu

    2017-01-01

    The aim of this research is to evaluate the change in the hand grip strength of the male arm wrestlers before and after a unit of exercise. The participants of the research consist of sportsmen (n=16) of Firat University arm wrestling team in 18-25 age group. Within the scope of the research, all of the tests and measurements (age, length, body…

  16. Why Carcinus maenas cannot get a grip on South Africa's wave ...

    African Journals Online (AJOL)

    Why Carcinus maenas cannot get a grip on South Africa's wave-exposed coastline. SL Hampton, CL Griffiths. Abstract. The European green crab Carcinus maenas has established considerable breeding populations in harbours and sheltered bays in the South-Western Cape, South Africa, but appears unable to flourish on ...

  17. Evaporation over a heterogeneous land surface - The EVA-GRIPS project

    NARCIS (Netherlands)

    Mengelkamp, H.T.; Beyrich, F.; Heinemann, G.; Ament, F.; Bange, J.; Berger, F.; Bosenberg, J.; Foken, T.; Hennemuth, B.; Heret, C.; Huneke, S.; Johnsen, K.P.; Kerschgens, M.; Kohsiek, W.; Leps, J.P.; Liebethal, C.; Lohse, H.; Mauder, M.; Meijninger, W.M.L.; Raasch, S.; Simmer, C.

    2006-01-01

    The representation of subgrid-scale surface heterogeneities in numerical weather and climate models has been a challenging problem for more than a decade. The Evaporation at Grid and Pixel Scale (EVA-GRIPS) project adds to the numerous studies on vegetation-atmosphere interaction processes through a

  18. Grip strength and quality of life in the second half of life: hope as a moderator.

    Science.gov (United States)

    Gum, Amber M; Segal-Karpas, Dikla; Avidor, Sharon; Ayalon, Liat; Bodner, Ehud; Palgi, Yuval

    2017-09-28

    The purpose of the current study was to investigate grip strength, hope, and their interaction as predictors of quality of life four years later in a nationally representative sample of older adults. Data were derived from the first (2005-2006) and second wave (2009) of the Israeli component of the Survey of Health Ageing and Retirement in Europe (SHARE; N = 344). Hope was measured by three items from the Hope   Scale, and quality of life was measured by the CASP-12 (Control, Autonomy, Self-Realization, and Pleasure). Multiple regression analyses were conducted. Grip strength at T1 predicted QoL in T2, but hope was not a significant predictor. Furthermore, hope moderated the effect of handgrip on QoL, such that the effect was weaker for higher levels of hope. As hypothesized, hope acted as a moderator, such that poor grip strength was associated with worse QoL for less hopeful older adults, but grip strength was not associated with QoL for more hopeful older adults. Findings are consistent with a theoretical conceptualization of hope as a buffer between physical challenges and negative outcomes like QoL. Encouraging a hopeful perspective could enhance QoL for older adults with decreased muscle strength.

  19. Calpain-GRIP Signaling in Nucleus Accumbens Core Mediates the Reconsolidation of Drug Reward Memory.

    Science.gov (United States)

    Liang, Jie; Li, Jia-Li; Han, Ying; Luo, Yi-Xiao; Xue, Yan-Xue; Zhang, Yàn; Zhang, Yán; Zhang, Li-Bo; Chen, Man-Li; Lu, Lin; Shi, Jie

    2017-09-13

    Exposure to drug-paired cues causes drug memories to be in a destabilized state and interfering with memory reconsolidation can inhibit relapse. Calpain, a calcium-dependent neutral cysteine protease, is involved in synaptic plasticity and the formation of long-term fear memory. However, the role of calpain in the reconsolidation of drug reward memory is still unknown. In the present study, using a conditioned place preference (CPP) model, we found that exposure to drug-paired contextual stimuli induced the activation of calpain and decreased the expression of glutamate receptor interacting protein 1 (GRIP1) in the nucleus accumbens (NAc) core, but not shell, of male rats. Infusions of calpain inhibitors in the NAc core immediately after retrieval disrupted the reconsolidation of cocaine/morphine cue memory and blocked retrieval-induced calpain activation and GRIP1 degradation. The suppressive effect of calpain inhibitors on the expression of drug-induced CPP lasted for at least 14 d. The inhibition of calpain without retrieval 6 h after retrieval or after exposure to an unpaired context had no effects on the expression of reward memory. Calpain inhibition after retrieval also decreased cocaine seeking in a self-administration model and this effect did not recover spontaneously after 28 d. Moreover, the knock-down of GRIP1 expression in the NAc core by lentivirus-mediated short-hairpin RNA blocked disruption of the reconsolidation of drug cue memories that was induced by calpain inhibitor treatment. These results suggest that calpain activity in the NAc core is crucial for the reconsolidation of drug reward memory via the regulation of GRIP1 expression. SIGNIFICANCE STATEMENT Calpain plays an important role in synaptic plasticity and long-term memory consolidation, however, its role in the reconsolidation of drug cue memory remains unknown. Using conditioned place preference and self-administration procedures, we found that exposure to drug-paired cues induced the

  20. Enhanced independence: experiences after regaining grip function in people with tetraplegia.

    Science.gov (United States)

    Wangdell, Johanna; Carlsson, Gunnel; Fridén, Jan

    2013-01-01

    To explore how surgical reconstruction of grip affects everyday life for patients with tetraplegia, with special emphasis on patients perspective of their perceived changes. Qualitative method. Eleven people (aged 22-73) with tetraplegia who had undergone surgical reconstruction to restore grip function. Qualitative interviews were conducted 7-17 months after surgery and analysed using Grounded theory. The core concept describing the participants experienced gains after grip reconstructive surgery was "enhanced independence". It was associated with changes in both practical and psychological aspects of independence. Practical aspects identified were: "perform more activities", "smoother everyday life", "renewed ability to participate in social activities", "less dependence on assistance" and "less restricted by physical environment". Psychological aspects of independence included "regained privacy", "increased manageability", "regained identity", "recapture a part of the body" and "share positive experiences with relatives and friends". Encompassing all categories was the concept "self-efficacy in hand control". It was seen as a result included in the enhanced independency core but also as an important factor for the development of all the other categories. Participants in this study experienced enhanced independence after grip reconstructive surgery and rehabilitation. The enhanced independence included both practical and physical aspects and it influenced all domains using the International Classification of Function, Disability and Health model; body function and structure, activities, participation, personal factors and environmental factors. Implications for Rehabilitation Patients with tetraplegia experience grip reconstruction as a useful intervention, an enhanced independence, related to their improved hand control. The increased hand control impacted not only physical aspects but also practical and psychological aspects. It also influenced social and

  1. From regained function to daily use: experiences of surgical reconstruction of grip in people with tetraplegia.

    Science.gov (United States)

    Wangdell, Johanna; Carlsson, Gunnel; Friden, Jan

    2014-01-01

    To capture patients' relearning processes from regained function to improvements in daily life after grip reconstructive surgery in tetraplegia. Eleven people with tetraplegia who underwent grip reconstructive surgery during February 2009 to March 2011. Qualitative interviews were conducted 7 to 17 months after surgery and analysed using grounded theory. Determination to reach a higher level of independence was the core concept to integrate regained function into daily life. There were 3 phases identified; "Initiate activity training," "Establish hand control in daily activities," and "Challenge dependence." Between the phases psychological stages occurred, first; "a belief in improved ability", and later in the process; "confidence in ability". The process to fully integrate regain function in daily life was described as long and time-consuming. However, the participants claimed it useful to do the skills training in their home environment, without long-term in clinic rehabilitation. Relearning activities in daily life after a grip reconstruction is a time-consuming and demanding process. It includes skills training, mental strategies and psychological stages together with environmental and social factors. Accordingly, rehabilitation after grip reconstruction in tetraplegia should focus on both grip skills and psychological stages, to encourage that patient's keep their determination and achieve greater independence. Implications for Rehabilitation There is a stepwise process to transform improved function into daily use. The most important factor to transform improved function into daily use was motivation to reach a higher independence. Other important factors were; skills training, use of individual learning strategies, belief and confidence in personal ability, social and environmental factors. There was a long and demanding process to fully transform the improved function into daily use. The participants preferred to do activity training in the specific

  2. A Strain-Based Method to Detect Tires’ Loss of Grip and Estimate Lateral Friction Coefficient from Experimental Data by Fuzzy Logic for Intelligent Tire Development

    Directory of Open Access Journals (Sweden)

    Jorge Yunta

    2018-02-01

    Full Text Available Tires are a key sub-system of vehicles that have a big responsibility for comfort, fuel consumption and traffic safety. However, current tires are just passive rubber elements which do not contribute actively to improve the driving experience or vehicle safety. The lack of information from the tire during driving gives cause for developing an intelligent tire. Therefore, the aim of the intelligent tire is to monitor tire working conditions in real-time, providing useful information to other systems and becoming an active system. In this paper, tire tread deformation is measured to provide a strong experimental base with different experiments and test results by means of a tire fitted with sensors. Tests under different working conditions such as vertical load or slip angle have been carried out with an indoor tire test rig. The experimental data analysis shows the strong relation that exists between lateral force and the maximum tensile and compressive strain peaks when the tire is not working at the limit of grip. In the last section, an estimation system from experimental data has been developed and implemented in Simulink to show the potential of strain sensors for developing intelligent tire systems, obtaining as major results a signal to detect tire’s loss of grip and estimations of the lateral friction coefficient.

  3. A Strain-Based Method to Detect Tires' Loss of Grip and Estimate Lateral Friction Coefficient from Experimental Data by Fuzzy Logic for Intelligent Tire Development.

    Science.gov (United States)

    Yunta, Jorge; Garcia-Pozuelo, Daniel; Diaz, Vicente; Olatunbosun, Oluremi

    2018-02-06

    Tires are a key sub-system of vehicles that have a big responsibility for comfort, fuel consumption and traffic safety. However, current tires are just passive rubber elements which do not contribute actively to improve the driving experience or vehicle safety. The lack of information from the tire during driving gives cause for developing an intelligent tire. Therefore, the aim of the intelligent tire is to monitor tire working conditions in real-time, providing useful information to other systems and becoming an active system. In this paper, tire tread deformation is measured to provide a strong experimental base with different experiments and test results by means of a tire fitted with sensors. Tests under different working conditions such as vertical load or slip angle have been carried out with an indoor tire test rig. The experimental data analysis shows the strong relation that exists between lateral force and the maximum tensile and compressive strain peaks when the tire is not working at the limit of grip. In the last section, an estimation system from experimental data has been developed and implemented in Simulink to show the potential of strain sensors for developing intelligent tire systems, obtaining as major results a signal to detect tire's loss of grip and estimations of the lateral friction coefficient.

  4. Muscle response to pneumatic hand tool torque reaction forces.

    Science.gov (United States)

    Radwin, R G; VanBergeijk, E; Armstrong, T J

    1989-06-01

    Surface electromyography was used for studying the effects of torque reaction force acting against the hand, on forearm muscle activity and grip force for five subjects operating right angle, air shut-off nutrunners. Four tools having increasing spindle torque were operated using short and long torque reaction times. Nutrunner spindle torque ranged between 30 Nm and 100 Nm. Short torque reaction time was considered 0.5 s while long torque reaction time was 2 s. Peak horizontal force was the greatest component of the reaction force acting against the hand and accounted for more than 97% of the peak resultant hand force. Peak hand force increased from 89 N for the smallest tool to 202 N for the largest tool. Forearm muscle rms EMG, scaled for grip force, indicated average flexor activity during the Torque-reaction phase was more than four times greater than the Pre-start and Post Shut-off phases, and two times greater than the Run-down phase. Flexor EMG activity during the Torque-reaction phase increased for increasing tool peak spindle torque. Average flexor rms EMG activity, scaled for grip force, during the Torque-reaction phase increased from 372 N for the 30 Nm nutrunner to 449 N for the 100 Nm nutrunner. Flexor rms EMG activity averaged during the Torque-reaction phase and scaled for grip force was 390 N for long torque reaction times and increased to 440 N for short torque reaction times. Flexor rms EMG integrated over the torque reaction phase was 839 Ns for long torque reaction times and decreased to 312 Ns for short torque reaction times. The average latency between tool spindle torque onset and peak initial flexor rms EMG for long torque reaction times was 294 ms which decreased to 161 ms for short torque reaction times. The average latency between peak tool spindle torque, just prior to tool shut-off, and peak final rms EMG for long torque reaction times was 97 ms for flexors and 188 ms for extensors, which decreased for short torque reaction times to 47

  5. Internal forces during static prehension: effects of age and grasp configuration.

    Science.gov (United States)

    Solnik, Stanislaw; Zatsiorsky, Vladimir M; Latash, Mark L

    2014-01-01

    The authors studied effects of healthy aging on 3 components of the internal force vector during static prehensile tasks. Young and older subjects held an instrumented handle using a 5-digit prismatic grasp under different digit configurations and external torques. Across digit configurations, older subjects showed larger internal normal (grip) and tangential (load-resisting) digit force components and larger internal moment of force. In contrast to earlier reports, safety margin values were not higher in the older subjects. The results show that the increased grip force in older persons is a specific example of a more general age-related problem reflected in the generation of large internal force vectors in prehensile tasks. It is possible that the higher internal forces increase the apparent stiffness of the hand+handle system and, hence, contribute to its stability. This strategy, however, may be maladaptive, energetically wasteful, and inefficient in ensuring safety of hand-held objects.

  6. Power grip, pinch grip, manual muscle testing or thenar atrophy – which should be assessed as a motor outcome after carpal tunnel decompression? A systematic review

    Directory of Open Access Journals (Sweden)

    Kale Swati

    2007-11-01

    Full Text Available Abstract Background Objective assessment of motor function is frequently used to evaluate outcome after surgical treatment of carpal tunnel syndrome (CTS. However a range of outcome measures are used and there appears to be no consensus on which measure of motor function effectively captures change. The purpose of this systematic review was to identify the methods used to assess motor function in randomized controlled trials of surgical interventions for CTS. A secondary aim was to evaluate which instruments reflect clinical change and are psychometrically robust. Methods The bibliographic databases Medline, AMED and CINAHL were searched for randomized controlled trials of surgical interventions for CTS. Data on instruments used, methods of assessment and results of tests of motor function was extracted by two independent reviewers. Results Twenty-two studies were retrieved which included performance based assessments of motor function. Nineteen studies assessed power grip dynamometry, fourteen studies used both power and pinch grip dynamometry, eight used manual muscle testing and five assessed the presence or absence of thenar atrophy. Several studies used multiple tests of motor function. Two studies included both power and pinch strength and reported descriptive statistics enabling calculation of effect sizes to compare the relative responsiveness of grip and pinch strength within study samples. The study findings suggest that tip pinch is more responsive than lateral pinch or power grip up to 12 weeks following surgery for CTS. Conclusion Although used most frequently and known to be reliable, power and key pinch dynamometry are not the most valid or responsive tools for assessing motor outcome up to 12 weeks following surgery for CTS. Tip pinch dynamometry more specifically targets the thenar musculature and appears to be more responsive. Manual muscle testing, which in theory is most specific to the thenar musculature, may be more

  7. Effect of Magnesium Carbonate Use on Repeated Open-Handed and Pinch Grip Weight-Assisted Pull-Ups.

    Science.gov (United States)

    Bacon, Nicholas T; Ryan, Greg A; Wingo, Jonathan E; Richardson, Mark T; Pangallo, Tracey; Bishop, Phillip A

    2018-01-01

    The purpose was to determine if pull-up performance was affected by the use of chalk (100% magnesium carbonate) during open-handed and pinch grip weight-assisted pull-ups (WAPU) in recreationally-trained rock climbers. Furthermore, the reliability of open-handed and pinch grip WAPU was also investigated. Recreationally-active volunteers (n = 9) completed six counterbalanced trials. Participants used chalk during four trials to determine the reliability (test-retest) of the open-handed and pinch grips. While two of the six trials were used to determine if open-handed and pinch grip WAPU performance was affected without using chalk. Three of the six trials included one set of open-handed WAPU, while the remaining trails included one set of pinch grip WAPU. Sets were performed until failure and consisted of either the open-handed or pinch grip pull-ups assisted by a 50% reduction of body weight. Heart rate, ratings of perceived exertion, perceived recovery scale and session-RPE were not significantly different (p > 0.05) among trials. Intraclass correlations (ICC's) for test-retest of the open-handed (R = 0.99) and pinch grip (R = 0.96) WAPU evidenced reliable values. When compared to the non-chalked trials, chalk improved both openhanded (mean = 22.8 ± 4.53 vs. mean no chalk = 19.7 ± 4.39 reps; p = 0.006,) and pinch grip (mean = 14.4 ± 4.47 vs. mean no chalk = 9.1 ± 4.83 reps; p = 0.007) WAPU. ICC's indicated a reliable measurement, while chalk improved performance for both open-handed and pinch grip WAPU when compared to no chalk trials.

  8. Force and motion

    CERN Document Server

    Robertson, William C

    2002-01-01

    Intimidated by inertia? Frightened by forces? Mystified by Newton s law of motion? You re not alone and help is at hand. The stop Faking It! Series is perfect for science teachers, home-schoolers, parents wanting to help with homework all of you who need a jargon-free way to learn the background for teaching middle school physical science with confidence. With Bill Roberton as your friendly, able but somewhat irreverent guide, you will discover you CAN come to grips with the basics of force and motion. Combining easy-to-understand explanations with activities using commonly found equipment, this book will lead you through Newton s laws to the physics of space travel. The book is as entertaining as it is informative. Best of all, the author understands the needs of adults who want concrete examples, hands-on activities, clear language, diagrams and yes, a certain amount of empathy. Ideas For Use Newton's laws, and all of the other motion principles presented in this book, do a good job of helping us to underst...

  9. EyeGrip: Detecting Targets in a Series of Uni-directional Moving Objects Using Optokinetic Nystagmus Eye Movements

    DEFF Research Database (Denmark)

    Jalaliniya, Shahram; Mardanbeigi, Diako

    2016-01-01

    in the screen, on the accuracy of EyeGrip. Based on the experiment results, we propose guidelines for designing EyeGrip-based interfaces. EyeGrip can be considered as an implicit gaze interaction technique with potential use in broad range of applications such as large screens, mobile devices and eyewear...... in a fast scrolling task where the system accurately (87%) detects the moving images that are visually appealing to the user, stops the scrolling and brings the item(s) of interest back to the screen....

  10. Direct observation of salts as micro-inclusions in the Greenland GRIP ice core

    DEFF Research Database (Denmark)

    Dahl-Jensen, Dorthe; Sakurai, Toshimitsu; Iizuka, Yoshinori

    2009-01-01

    We provide the first direct evidence that a number of water-soluble compounds, in particular calcium sulfate (CaSO4·2H2O) and calcium carbonate (CaCO3), are present as solid, micron-sized inclusions within the Greenland GRIP ice core. The compounds are detected by two independent methods: micro......-Raman spectroscopy of a solid ice sample, and energy-dispersive X-ray spectroscopy of individual inclusions remaining after sublimation. CaSO4·2H2O is found in abundance throughout the Holocene and the last glacial period, while CaCO3 exists mainly in the glacial period ice. We also present size and spatial...... distributions of the micro-inclusions. These results suggest that water-soluble aerosols in the GRIP ice core are dependable proxies for past atmospheric conditions. Udgivelsesdato: December...

  11. GRIPS: a mission with a flavour and a very broad scientific scope

    International Nuclear Information System (INIS)

    Iyudin, Anatoli F.

    2008-01-01

    The primary scientific goal of the GRIPS mission is to study the early universe using γ-ray bursts. GRIPS, fully described in a paper by Greiner et al. (2008), is a new generation gamma-ray observatory capable of unprecedented spectroscopy over a wide range of γ-ray energies (200 keV--50 MeV) and of polarimetry (200-1000 keV). Scientific goals achievable by this mission are very broad, and include apart of the primary goal also direct measurements of supernova interiors through γ-ray lines from radioactive products of nucleosynthesis, nuclear astrophysics with massive stars and novae, and studies of particle acceleration near compact objects, interstellar shocks, supernova remnants, superbubbles and clusters of galaxies.

  12. Grip preference, dermatoglyphics, and hand use in captive chimpanzees (Pan troglodytes).

    Science.gov (United States)

    Hopkins, William D; Russell, Jamie L; Hostetter, Autumn; Pilcher, Dawn; Dahl, Jeremy F

    2005-09-01

    This paper examined the association between grip type, hand use, and fingerprint patterns in a sample of captive chimpanzees. Grip type for simple reaching was assessed for the left and right hand and classified as thumb-index, middle-index, or single-digit responses. Fingerprint patterns were characterized as whorls, loops, or arches on each finger. The results indicated that chimpanzees exhibit significantly more thumb-index responses for the right compared to the left hand. In addition, thumb-index responses were more prevalent for subjects that had a whorl compared to a loop or arch on their thumb. The results suggest that fingerprint patterns are associated with individual differences in grasping type in chimpanzees as well as some variation in hand use. (c) 2005 Wiley-Liss, Inc.

  13. Quantifying Soldier Shooting Performance of the M4 Carbine with and without a Vertical Grip

    Science.gov (United States)

    2015-01-01

    thereof. Destroy this report when it is no longer needed. Do not return it to the originator . Army Research Laboratory Aberdeen Proving Ground, MD...that my wrist would be canted and start cramping . 16 Yes, light weight and ease of use. The vertical grip may be useful to move your hand off of barrel...Sheets This appendix appears in its original form, without editorial change. 28 DEMOGRAPHIC

  14. The Impact of Hand Grip Strength Exercises on the Target Shooting Accuracy Score for Archers

    Science.gov (United States)

    Sezer, Süreyya Yonca

    2017-01-01

    The purpose of this research is to investigate the impact of hand grip strength exercises on the target shooting accuracy score for male archers. Thirty male archers (n1 = 15, 19.85 ± 1.35, n2 = 15 19.71 ± 1.31) ranging 18-20 years old were included in our study from the archery team of the city of Elazig, department of youth sports. The…

  15. Serotonergic-postsynaptic receptors modulate gripping-induced immobility episodes in male taiep rats.

    Science.gov (United States)

    Eguibar, José R; Cortés, M C; Ita, M L

    2009-09-01

    The Taiep rat is a myelin mutant with a motor syndrome characterized by tremor, ataxia, immobility, epilepsy, and paralysis. The rat shows a hypomyelination followed by a progressive demyelination. During immobilities taiep rats show a REM-like sleep pattern and a disorganized sleep-wake pattern suggesting taiep rats as a model of narcolepsy-cataplexy. Our study analyzed the role of postsynaptic serotonin receptors in the expression of gripping-induced immobility episodes (IEs) in 8-month-old male taiep rats. The specific postsynaptic serotonin agonist +/-1-(2,5-dimethoxy-4-iodoamphetamine hydrochloride (+/-DOI) decreased the frequency of gripping-induced IEs, but that was not the case with alpha-methyl-serotonin maleate (alpha-methyl-5HT), a nonspecific postsynaptic agonist. Although the serotonin antagonists, ketanserine and metergoline, produced a biphasic effect, first a decrease followed by an increase with higher doses, similar effects were obtained with a mean duration of gripping-induced IEs. These findings correlate with the pharmacological observations in narcoleptic dogs and humans in which serotonin-reuptake inhibitors improve cataplexy, particularly in long-term treatment that could change the serotonin receptor levels. Polysomnographic recordings showed an increase in the awakening time and a decrease in the slow wave and rapid eye movement sleep concomitant with a decrease in immobilities after use of +/-DOI, this being stronger with the highest dose. Taken together, our results show that postsynaptic serotonin receptors are involved in the modulation in gripping-induced IEs caused by the changes in the organization of the sleep-wake cycle in taiep rats. It is possible that specific agonists, without side effects, could be a useful treatment in human narcoleptic patients. 2009 Wiley-Liss, Inc.

  16. Direct Tensile Strength of Steel Fiber Reinforced Concrete by Using Clamping Grips

    OpenAIRE

    ISHIGURO, Satoru; NAKAYA, Mitsuo

    1985-01-01

    This report presents the tensile strength behavior of steel fiber reinforced concrete (SFRC). In this experimental work, direct tensile test by using clamping grips is carried out for the prismatic mortar and concrete specimens reinforced with steel fibers. The volume content of steel fibers varies from 1.0 percent to 2.0 percent of the concrete volume. Test results for different fiber content, fiber length, and specimen size are presented. The results are compared with the results of indirec...

  17. Limited Investigation of the Effects of Elevator Rate Limiting and Stick Dynamics on Longitudinal Pilot Induced Oscillations (HAVE GRIP)

    National Research Council Canada - National Science Library

    Peters, Patrick

    1996-01-01

    This report presents the results of the HAVE GRIP flight test program. This program performed a limited investigation of the effects of stick dynamics and elevator rate limiting on longitudinal pilot induced oscillations (PIOs...

  18. Influence of the gripping fixture on the modified compact tension test results: Evaluation of the experiments on cylindrical concrete specimens

    Czech Academy of Sciences Publication Activity Database

    Holušová, T.; Lozano, M.; Canteli, A.; Komárková, T.; Kocáb, D.; Seitl, Stanislav

    2015-01-01

    Roč. 15, č. 2 (2015) ISSN 1804-4824 Institutional support: RVO:68081723 Keywords : Modified compact tension test * fracture parametr * Cementitious composites * Aramis measurement * grips Subject RIV: JL - Materials Fatigue, Friction Mechanics

  19. Nutritional status is the major factor affecting grip strength of African HIV patients before and during antiretroviral treatment

    DEFF Research Database (Denmark)

    Filteau, Suzanne; PrayGod, G; Woodd, Susannah L

    2017-01-01

    OBJECTIVES: Low grip strength is a marker of frailty and a risk factor for mortality among HIV patients and other populations. We investigated factors associated with grip strength in malnourished HIV patients at referral to ART, and at 12 weeks and 2-3 years after starting ART. METHODS: The study...... involved HIV-infected Zambian and Tanzanian participants recruited to the NUSTART trial when malnourished (body mass index ART. The relationship of grip strength to nutritional, infectious and demographic factors was assessed by multivariable linear regression at referral...... for ART (n=1742) and after 12 weeks (n=778) and 2-3 years of ART (n=273). RESULTS: In analyses controlled only for sex, age and height, most nutrition and infection-related variables were associated with grip strength. However, in multivariable analyses, consistent associations were seen for fat-free mass...

  20. Communication skills training for general practitioners to promote patient coping: the GRIP approach.

    Science.gov (United States)

    Mjaaland, Trond A; Finset, Arnstein

    2009-07-01

    To develop, perform and test the effects of a communication skills training program for general practitioners (GPs). The program specifically addresses the patients' coping and resources despite more or less severe psychological or physical illness. A training model was developed, based on cognitive therapy and solution-focused therapy. The training was given the acronym GRIP after its main content: Get a measure of the patient's subjective complaints and illness attributions. Respond to the patient's understanding of the complaints. Identify resources and solutions. Promote positive coping. The study involved a quasi-experimental design in which 266 consultations with 25 GPs were video recorded. Forty hours of communication skills training were given to the intervention group. Consultation duration, patient age and distress determined the frequency of the GRIP communication. There was a significant effect of training on four particular subcategories of the GRIP techniques. The effect of the training was most evident in a subgroup of GPs who used little or no resource-oriented communication before training. This pilot training model may help change the GPs' communicative pattern with patients in some situations. Communication skills training programmes that emphasize patient attributions and personal resources should be developed further and tested in general practice settings with an aim to promote patient coping.

  1. Cortical activation during power grip task with pneumatic pressure gauge: an fMRI study

    Science.gov (United States)

    Mohamad, M.; Mardan, N. H.; Ismail, S. S.

    2017-05-01

    Aging is associated with a decline in cognitive and motor function. But, the relationships with motor performance are less well understood. In this study, functional magnetic resonance imaging (fMRI) was used to assess cortical activation in older adults. This study employed power grip task that utilised block paradigm consisted of alternate 30s rest and active. A visual cue was used to pace the hand grip movement that clenched a cylindrical rubber bulb connected with pressure pneumatic gauge that measure the pressure (Psi). The objective of this study is determined the brain areas activated during motor task and the correlation between percentage signal change of each motor area (BA 4 and 6) and hand grip pressure. Result showed there was a significant difference in mean percentage signal change in BA 4 and BA 6 in both hemispheres and negative correlation obtained in BA 4 and BA 6. These results indicate that a reduced ability in the motor networks contribute to age-related decline in motor performance.

  2. Cortical activation during power grip task with pneumatic pressure gauge: an fMRI study

    International Nuclear Information System (INIS)

    Mohamad, M; Ismail, S S; Mardan, N H

    2017-01-01

    Aging is associated with a decline in cognitive and motor function. But, the relationships with motor performance are less well understood. In this study, functional magnetic resonance imaging (fMRI) was used to assess cortical activation in older adults. This study employed power grip task that utilised block paradigm consisted of alternate 30s rest and active. A visual cue was used to pace the hand grip movement that clenched a cylindrical rubber bulb connected with pressure pneumatic gauge that measure the pressure (Psi). The objective of this study is determined the brain areas activated during motor task and the correlation between percentage signal change of each motor area (BA 4 and 6) and hand grip pressure. Result showed there was a significant difference in mean percentage signal change in BA 4 and BA 6 in both hemispheres and negative correlation obtained in BA 4 and BA 6. These results indicate that a reduced ability in the motor networks contribute to age-related decline in motor performance. (paper)

  3. Grip and Muscle Strength Dynamometry Are Reliable and Valid in Patients With Unhealed Minor Burn Wounds.

    Science.gov (United States)

    Gittings, Paul; Salet, Myrthe; Burrows, Sally; Ruettermann, Mike; Wood, Fiona M; Edgar, Dale

    Small burns are common and can cause disproportionate levels of disability. The ability to measure muscle impairment and consequent functional disability is a necessity during rehabilitation of patients. This study aimed to determine the reliability and validity of grip and muscle strength dynamometry in patients with unhealed, minor burn wounds. Grip and muscle strength were assessed three times on each side. Assessment occurred at presentation for the initial injury and again every other day (or every 5 days beyond 10 days post injury) until discharge from the service. Reliability was assessed using intraclass correlation. Minimum detectable differences were calculated for each muscle group. Validity was assessed using regression analysis, incorporating appropriate burn severity measures and patient demographics. Thirty patients with TBSA ≤15% were assessed. Both grip and muscle strength demonstrated very good reliability (intraclass correlation coefficient: 0.85-0.96). Minimum detectable differences ranged from 3.8 to 8.0 kg. Validity of both forms of dynamometry was confirmed through associations with gender for all muscle groups (P dynamometry are reliable and valid assessments of strength and are applicable for clinical use in patients who have unhealed, minor burn wounds.

  4. Nutritional status is the major factor affecting grip strength of African HIV patients before and during antiretroviral treatment.

    Science.gov (United States)

    Filteau, S; PrayGod, G; Woodd, S L; Friis, H; Heimburger, D C; Koethe, J R; Kelly, P; Kasonka, L; Rehman, A M

    2017-10-01

    Low grip strength is a marker of frailty and a risk factor for mortality among HIV patients and other populations. We investigated factors associated with grip strength in malnourished HIV patients at referral to ART, and at 12 weeks and 2-3 years after starting ART. The study involved HIV-infected Zambian and Tanzanian participants recruited to the NUSTART trial when malnourished (body mass index <18.5 kg/m 2 ) and requiring ART. The relationship of grip strength to nutritional, infectious and demographic factors was assessed by multivariable linear regression at referral for ART (n = 1742) and after 12 weeks (n = 778) and 2-3 years of ART (n = 273). In analyses controlled only for sex, age and height, most nutrition and infection-related variables were associated with grip strength. However, in multivariable analyses, consistent associations were seen for fat-free mass index, mid-upper arm circumference, haemoglobin and systolic blood pressure, and a variable association with fat mass index in men. C-reactive protein and CD4 count had limited independent effects on grip strength, while receiving tuberculosis treatment was associated with weaker grip strength. In this population of originally malnourished HIV patients, poor grip strength was more strongly and independently associated with nutritional than with infection and inflammation variables. Programmes to improve health and survival of HIV patients should incorporate nutritional assessment and management and could use grip strength as a functional indicator of improving nutrition. © 2017 John Wiley & Sons Ltd.

  5. Assessment of grip strength with the modified sphygmomanometer test: association between upper limb global strength and motor function

    Science.gov (United States)

    Martins, Júlia C.; Aguiar, Larissa T.; Lara, Eliza M.; Teixeira-Salmela, Luci F.; Faria, Christina D. C. M.

    2015-01-01

    ABSTRACT Background: Grip strength, commonly evaluated with the handgrip dynamometer, is a good indicator of upper limb (UL) function in stroke subjects and may reflect the global strength deficits of the whole paretic UL. The Modified Sphygmomanometer Test (MST) also provides objective and adequate measures at low-cost. Objective: To assess whether grip strength values obtained by using the MST and those obtained by using a handgrip dynamometer would present similar correlations with the global strength and motor function of the paretic UL in subjects with stroke, both in the subacute and chronic phases. Method: Measures of grip strength (MST and handgrip dynamometer), UL global strength (MST and hand-held dynamometer), and UL motor function (Fugl-Meyer motor assessment scale) were obtained with 33 subacute and 44 chronic stroke subjects. Pearson and Spearman correlation coefficients were calculated and Stepwise multiple regression analyses were performed to investigate predictor variables of grip strength (α=0.05). Results: Significant correlations of similar magnitude were found between measures of global strength of the paretic UL and grip strength assessed with both the MST (0.66≤r≤0.78) and handgrip dynamometer (0.66≤r≤0.78) and between UL motor function and grip strength assessed with both the MST (0.50≤rs≤0.51) and hand-held dynamometer (0.50≤rs≤0.63) in subacute and chronic stroke subjects. Only global strength remained as a significant predictor variable of grip strength for the MST (0.43≤R2≤0.61) and for the handgrip dynamometer (0.44≤R2≤0.61) for both stroke subgroups. Conclusion: Grip strength assessed with the MST could be used to report paretic UL global strength. PMID:26647752

  6. Assessment of grip strength with the modified sphygmomanometer test: association between upper limb global strength and motor function

    Directory of Open Access Journals (Sweden)

    Júlia C. Martins

    2015-12-01

    Full Text Available ABSTRACT Background: Grip strength, commonly evaluated with the handgrip dynamometer, is a good indicator of upper limb (UL function in stroke subjects and may reflect the global strength deficits of the whole paretic UL. The Modified Sphygmomanometer Test (MST also provides objective and adequate measures at low-cost. Objective: To assess whether grip strength values obtained by using the MST and those obtained by using a handgrip dynamometer would present similar correlations with the global strength and motor function of the paretic UL in subjects with stroke, both in the subacute and chronic phases. Method: Measures of grip strength (MST and handgrip dynamometer, UL global strength (MST and hand-held dynamometer, and UL motor function (Fugl-Meyer motor assessment scale were obtained with 33 subacute and 44 chronic stroke subjects. Pearson and Spearman correlation coefficients were calculated and Stepwise multiple regression analyses were performed to investigate predictor variables of grip strength (α=0.05. Results: Significant correlations of similar magnitude were found between measures of global strength of the paretic UL and grip strength assessed with both the MST (0.66≤r≤0.78 and handgrip dynamometer (0.66≤r≤0.78 and between UL motor function and grip strength assessed with both the MST (0.50≤rs≤0.51 and hand-held dynamometer (0.50≤rs≤0.63 in subacute and chronic stroke subjects. Only global strength remained as a significant predictor variable of grip strength for the MST (0.43≤R2≤0.61 and for the handgrip dynamometer (0.44≤R2≤0.61 for both stroke subgroups. Conclusion: Grip strength assessed with the MST could be used to report paretic UL global strength.

  7. Oxytocin decreases handgrip force in reaction to infant crying in females without harsh parenting experiences

    NARCIS (Netherlands)

    Bakermans-Kranenburg, M.J.; van IJzendoorn, M.H.; Riem, M.M.E.; Tops, M.; Alink, L.R.A.

    2012-01-01

    Infant crying can elicit sensitive caregiving as well as hostility and harsh parenting responses. In the current study (N=42 females) with a double-blind experimental design, we tested the effect of intranasal oxytocin administration on the use of excessive force using a hand-grip dynamometer during

  8. Effects of transcranial direct current stimulation on the control of finger force during dexterous manipulation in healthy older adults.

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    Pranav J Parikh

    Full Text Available The contribution of poor finger force control to age-related decline in manual dexterity is above and beyond ubiquitous behavioral slowing. Altered control of the finger forces can impart unwanted torque on the object affecting its orientation, thus impairing manual performance. Anodal transcranial direct current stimulation (tDCS over primary motor cortex (M1 has been shown to improve the performance speed on manual tasks in older adults. However, the effects of anodal tDCS over M1 on the finger force control during object manipulation in older adults remain to be fully explored. Here we determined the effects of anodal tDCS over M1 on the control of grip force in older adults while they manipulated an object with an uncertain mechanical property. Eight healthy older adults were instructed to grip and lift an object whose contact surfaces were unexpectedly made more or less slippery across trials using acetate and sandpaper surfaces, respectively. Subjects performed this task before and after receiving anodal or sham tDCS over M1 on two separate sessions using a cross-over design. We found that older adults used significantly lower grip force following anodal tDCS compared to sham tDCS. Friction measured at the finger-object interface remained invariant after anodal and sham tDCS. These findings suggest that anodal tDCS over M1 improved the control of grip force during object manipulation in healthy older adults. Although the cortical networks for representing objects and manipulative actions are complex, the reduction in grip force following anodal tDCS over M1 might be due to a cortical excitation yielding improved processing of object-specific sensory information and its integration with the motor commands for production of manipulative forces. Our findings indicate that tDCS has a potential to improve the control of finger force during dexterous manipulation in older adults.

  9. Effects of transcranial direct current stimulation on the control of finger force during dexterous manipulation in healthy older adults.

    Science.gov (United States)

    Parikh, Pranav J; Cole, Kelly J

    2015-01-01

    The contribution of poor finger force control to age-related decline in manual dexterity is above and beyond ubiquitous behavioral slowing. Altered control of the finger forces can impart unwanted torque on the object affecting its orientation, thus impairing manual performance. Anodal transcranial direct current stimulation (tDCS) over primary motor cortex (M1) has been shown to improve the performance speed on manual tasks in older adults. However, the effects of anodal tDCS over M1 on the finger force control during object manipulation in older adults remain to be fully explored. Here we determined the effects of anodal tDCS over M1 on the control of grip force in older adults while they manipulated an object with an uncertain mechanical property. Eight healthy older adults were instructed to grip and lift an object whose contact surfaces were unexpectedly made more or less slippery across trials using acetate and sandpaper surfaces, respectively. Subjects performed this task before and after receiving anodal or sham tDCS over M1 on two separate sessions using a cross-over design. We found that older adults used significantly lower grip force following anodal tDCS compared to sham tDCS. Friction measured at the finger-object interface remained invariant after anodal and sham tDCS. These findings suggest that anodal tDCS over M1 improved the control of grip force during object manipulation in healthy older adults. Although the cortical networks for representing objects and manipulative actions are complex, the reduction in grip force following anodal tDCS over M1 might be due to a cortical excitation yielding improved processing of object-specific sensory information and its integration with the motor commands for production of manipulative forces. Our findings indicate that tDCS has a potential to improve the control of finger force during dexterous manipulation in older adults.

  10. Stress examination of flexor tendon pulley rupture in the crimp grip position: a 1.5-Tesla MRI cadaver study

    Energy Technology Data Exchange (ETDEWEB)

    Bayer, Thomas; Janka, Rolf [University of Erlangen-Nuremberg, Department of Radiology, Erlangen (Germany); Fries, Simon [Cantonal Hospital Lucerne, Orthopaedic Department, Wolhusen (Switzerland); Schweizer, Andreas [University of Zurich, Department of Orthopaedics, Balgrist, Zurich (Switzerland); Schoeffl, Isabelle [Klinikum Bamberg, Department of Pediatrics, Bamberg (Germany); Bongartz, Georg [University Basel, Department of Radiology, Basel (Switzerland)

    2015-01-15

    The objectives of this study were the evaluation of flexor tendon pulley rupture of the fingers in the crimp grip position using magnetic resonance imaging (MRI) and the comparison of the results with MRI in the neutral position in a cadaver study. MRI in the crimp grip position and in the neutral position was performed in 21 cadaver fingers with artificially created flexor tendon pulley tears (combined pulley rupture, n = 14; single pulley rupture, n = 7). Measurement of the distance between the tendon and bone was performed. Images were evaluated by two readers, first independently and in cases of discrepancy in consensus. Sensitivity and specificity for detecting combined pulley ruptures were calculated. Tendon bone distances were significantly higher in the crimp grip position than in the neutral position. Sensitivity and specificity for detecting combined pulley rupture were 92.86 % and 100 % respectively in the crimp grip position and 78.57 % and 85.71 % respectively in the neutral position. Kappa values for interobserver reliability were 0.87 in the crimp grip position and 0.59 in the neutral position. MRI examination in the crimp grip position results in higher tendon bone distances by subjecting the pulleys to a higher strain, which facilitates image evaluation with higher interobserver reliability, higher sensitivity, and higher specificity for combined pulley rupture compared with examination in the neutral position. (orig.)

  11. Stress examination of flexor tendon pulley rupture in the crimp grip position: a 1.5-Tesla MRI cadaver study

    International Nuclear Information System (INIS)

    Bayer, Thomas; Janka, Rolf; Fries, Simon; Schweizer, Andreas; Schoeffl, Isabelle; Bongartz, Georg

    2015-01-01

    The objectives of this study were the evaluation of flexor tendon pulley rupture of the fingers in the crimp grip position using magnetic resonance imaging (MRI) and the comparison of the results with MRI in the neutral position in a cadaver study. MRI in the crimp grip position and in the neutral position was performed in 21 cadaver fingers with artificially created flexor tendon pulley tears (combined pulley rupture, n = 14; single pulley rupture, n = 7). Measurement of the distance between the tendon and bone was performed. Images were evaluated by two readers, first independently and in cases of discrepancy in consensus. Sensitivity and specificity for detecting combined pulley ruptures were calculated. Tendon bone distances were significantly higher in the crimp grip position than in the neutral position. Sensitivity and specificity for detecting combined pulley rupture were 92.86 % and 100 % respectively in the crimp grip position and 78.57 % and 85.71 % respectively in the neutral position. Kappa values for interobserver reliability were 0.87 in the crimp grip position and 0.59 in the neutral position. MRI examination in the crimp grip position results in higher tendon bone distances by subjecting the pulleys to a higher strain, which facilitates image evaluation with higher interobserver reliability, higher sensitivity, and higher specificity for combined pulley rupture compared with examination in the neutral position. (orig.)

  12. Tipos de preensão e movimentos do punho durante atividade de manuseio de carga Types of grip and wrist movements during load handling activities

    Directory of Open Access Journals (Sweden)

    RS Padula

    2006-01-01

    Full Text Available INTRODUÇÃO: O tipo de tarefa realizada determina o tipo de preensão utilizada, a força aplicada, bem como as posturas adotadas para sua execução. Diferentes posturas e preensões envolvidas nessas tarefas apresentam maiores ou menores riscos de lesões musculoesqueléticas. Objetivo: Descrever os tipos de preensão empregados durante atividades de manuseio de cargas de 5 e 10kg entre superfícies de alturas diferentes e, quantificar os movimentos de flexo/extensão, desvio radial e ulnar do punho registrados por meio da eletrogoniometria. Método: 10 voluntários masculinos manusearam caixa entre superfícies de alturas diferentes. Os tipos de preensão utilizados foram filmados. Diferentes categorias de preensão utilizadas durante essa tarefa foram identificadas. As amplitudes de movimentos e a porcentagem de tempo gasto dentro e fora das faixas de amplitudes pré-estabelecidas (15(0 de flexão e extensão, 10(0 de desvio radial, e 15(0 desvio ulnar foram determinadas. Uma análise de univariância foi utilizada para avaliar diferenças significativas entre a antropometria das mãos dos voluntários, e entre os movimentos utilizados para o manuseio de cargas e alturas diferentes. Resultados e Conclusões: Os resultados mostraram que as alturas das superfícies para as quais os objetos eram manuseados influenciaram significativamente (p=0,000 as amplitudes articulares, contudo não houve diferença nos movimentos para as diferentes massas das cargas manuseadas (p=0,43. Tempo acima do considerado recomendável foi gasto em desvio radial quando os manuseios envolviam superfícies altas. Recomendações sobre local adequado para o acondicionamento de material a ser manuseado deveriam constar nos programas de treinamento visando a prevenção de lesões musculoesqueléticas.Background: The type of task performed determines the type of grip utilized, the force applied and the postures adopted for carrying out the task. The different postures

  13. Hip muscle and hand-grip strength to differentiate between older fallers and non-fallers: a cross-sectional validity study

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    Gafner SC

    2017-12-01

    Full Text Available Simone C Gafner,1,2 Caroline H Bastiaenen,2,3 Serge Ferrari,4 Gabriel Gold,5 Philippe Terrier,6,7 Roger Hilfiker,8 Lara Allet1,91Department of Physiotherapy, HES-SO University of Applied Sciences and Arts of Western Switzerland, Geneva, Switzerland; 2Department of Epidemiology, Research Program Functioning and Rehabilitation, CAPHRI, Maastricht University, Maastricht, the Netherlands; 3Department of Health, School of Health Professions, Zurich University of Applied Sciences, Winterthur, 4Department of Internal Medicine Specialties, 5Department of Internal Medicine, Rehabilitation and Geriatrics, University Hospitals and University of Geneva, Geneva, 6Department of Research, Clinique romande de réadaptation SUVACare, 7Department of Research, Institute for Research in Rehabilitation, Sion, 8Department of Physiotherapy, School of Health Sciences, HES-SO Valais-Wallis, University of Applied Sciences and Arts of Western Switzerland, Valais, 9Department of Community Medicine, University Hospitals and University of Geneva, Geneva, Switzerland Background: Hip muscle weakness in older people seems to be an influencing factor of falls. Currently, it is unclear which muscles out of the hip muscle group play an important role in older people. A validating process in the measurement regarding muscle strength related to falls is necessary before answering that question.Objective: Firstly, we aimed to investigate which hip muscle group strength shows an acceptable level of distinction between older adult fallers and non-fallers compared to a predefined external criterion regarding falling. Secondly, we aimed to compare the same outcomes and questions for hand-grip strength in relation to the same external criterion.Design: This study was a cross-sectional validity study.Methods: The maximum voluntary isometric strength (MVIS and the rate of force generation of hip abductors (ABD, adductors, internal and external rotators, extensors, and flexors were measured

  14. Quantitative Analysis of Lateral Pinch Force in Quadriplegic Patients Using Functional Neuromuscular Stimulation with Computer Stimulation

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    Ali Esteki

    2004-10-01

    Full Text Available Objective: In some applications of functional neuromuscular stimulation (FNS, the distal joint of the thumb (IP in quadriplegic patients is sometimes surgically fused at zero degrees and the FPL is stimulated. This prevents hyperextension and extreme flexion of the IP joint during lateral pinch. However, IP joint fusion removes one degree of freedom from the thumb and may reduce the grip force. An alternative approach, preferably without surgical alterations, using sufficient electrical stimulation of selected muscles was investigated. A 3D model of prehensile lateral pinch was developed. Computer simulation of the model was used to find an approach providing the appropriate posture and adequate lateral grip force for quadriplegic patients using FNS. Materials & Methods: The model consists of a multi-rigid-body system connected by one or two degree(s of freedom joints acted upon by passive resistive moments, active muscle moments and moments of external contact forces. Passive resistive moments were measured at each joint, active muscle moments were computed using a simple muscle model, and moments of external force were computed based on a force-displacement relationship for finger pads. In addition to the current strategy, two possible alternatives were studied: increasing the fused joint angle and activation of multiple muscles without joint fusion. Normal component of the grip force and its angle with respect to the horizontal plane were computed and compared for the studied cases. Results: Results showed, by using the current FNS strategy, a convenient posture and a grip force of 10.1 (N are achieved which is comparable to what is measured experimentally and introduced in the literature. Increasing the joint fusion angle from 0 to 15 and 30 degrees in parallel with the activation of FPL increased the grip force from 10.1 to 10.7 and 11.2 (N, respectively, but resulted in inconvenient posture. Among all different combinations of the muscles

  15. Tightening grip

    Science.gov (United States)

    Strukov, Dmitri B.

    2018-01-01

    Engineering channels for ion transport in a SiGe solid-state electrolyte layer allows one to significantly decrease the spatial and temporal variations of the electrical characteristics in resistive switching memories.

  16. Gloss, colour and grip: multifunctional epidermal cell shapes in bee- and bird-pollinated flowers.

    Science.gov (United States)

    Papiorek, Sarah; Junker, Robert R; Lunau, Klaus

    2014-01-01

    Flowers bear the function of filters supporting the attraction of pollinators as well as the deterrence of floral antagonists. The effect of epidermal cell shape on the visual display and tactile properties of flowers has been evaluated only recently. In this study we quantitatively measured epidermal cell shape, gloss and spectral reflectance of flowers pollinated by either bees or birds testing three hypotheses: The first two hypotheses imply that bee-pollinated flowers might benefit from rough surfaces on visually-active parts produced by conical epidermal cells, as they may enhance the colour signal of flowers as well as the grip on flowers for bees. In contrast, bird-pollinated flowers might benefit from flat surfaces produced by flat epidermal cells, by avoiding frequent visitation from non-pollinating bees due to a reduced colour signal, as birds do not rely on specific colour parameters while foraging. Moreover, flat petal surfaces in bird-pollinated flowers may hamper grip for bees that do not touch anthers and stigmas while consuming nectar and thus, are considered as nectar thieves. Beside this, the third hypothesis implies that those flower parts which are vulnerable to nectar robbing of bee- as well as bird-pollinated flowers benefit from flat epidermal cells, hampering grip for nectar robbing bees. Our comparative data show in fact that conical epidermal cells are restricted to visually-active parts of bee-pollinated flowers, whereas robbing-sensitive parts of bee-pollinated as well as the entire floral surface of bird-pollinated flowers possess on average flat epidermal cells. However, direct correlations between epidermal cell shape and colour parameters have not been found. Our results together with published experimental studies show that epidermal cell shape as a largely neglected flower trait might act as an important feature in pollinator attraction and avoidance of antagonists, and thus may contribute to the partitioning of flower-visitors.

  17. Characterization of the spontaneous and gripping-induced immobility episodes on taiep rats.

    Science.gov (United States)

    Cortés, Ma Del Carmen; Gavito, Berenice; Ita, Martha L; Valencia, Jaime; Eguibar, José R

    2005-11-01

    In 1989, we described a new autosomic-recessive myelin-mutant rat that develops a progressive motor syndrome characterized by tremor, ataxia, immobility episodes (IEs), epilepsy, and paralysis. taiep is the acronym of these symptoms. The rat developed a hypomyelination, followed by demyelination. At an age of 7-8 months, taiep rats developed IEs, characterized electroencephalographically by REM sleep-like cortical activity. In our study, we analyzed the ontogeny of gripping-induced IEs between 5 and 18 months, their dependence to light-dark changes, sexual dimorphism, and susceptibility to mild stress. Our results showed that IEs start at an age of 6.5 months, with a peak frequency between 8.5 and 9.5 months. IEs have two peaks, one in the morning (0800-1000 h) and a second peak in the middle of the night (2300-0100 h). Spontaneous IEs showed an even distribution with a mean of 3 IEs every 2 h. IEs are sexually dimorphic being more common in male rats. The IEs can be induced by gripping the rat by the tail or the thorax, but most of the IEs were produced by gripping the tail. Mild stress produced by i.p. injection of physiological saline significantly decreased IEs. These results suggested that IEs are dependent on several biological variables, which are caused by hypomyelination, followed by demyelization, which causes alterations in the brainstem and hypothalamic mechanisms responsible for the sleep-wake cycle regulation, producing emergence of REM sleep-like behavior during awake periods. (c) 2005 Wiley-Liss, Inc.

  18. REDUCED HAND GRIP STRENGTH IN OVERWEIGHT AND OBESE CHRONIC HEPATITIS C PATIENTS

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    Juliana Paula BRUCH

    Full Text Available ABSTRACT Background Hepatitis C is a liver disease that causes significant changes in metabolism, and also has an impact on nutritional status. Objective To evaluate the nutritional status and cardiovascular risk in patients with chronic hepatitis C. Methods This cross-sectional study investigated 58 patients with chronic hepatitis C, non-cirrhotic and were not under active pharmacological treatment. Patients with significant alcohol consumption (greater than 10 g ethanol/day were excluded. Patients underwent nutritional assessment through anthropometric measurements and functional assessment using hand grip strength by dynamometry. The physical activity was assessed using the International Physical Activity Questionnaire. Patients also underwent clinical and laboratory evaluation. Cardiovascular risk was calculated by the Framingham score. Results The mean age of patients was 51.6±9.7 years, 55.2% were female, and 79.3% had genotype 1. The most prevalent degree of fibrosis was F1 (37.9% followed by F2 (27.6% and F3 (1.7%. The prevalence of overweight/obesity considering the body mass index was 70.7%. However, 57.7% of men and 68.8% of women were considered malnourished according to hand grip strength. These patients also had waist circumference (93.5±10.7 cm and neck circumference (37.0±3.6 cm high. Almost 60% of patients were considered sedentary or irregularly active. In relation to cardiovascular risk, 50% of patients had high risk of suffering a cardiovascular event within 10 years. Conclusion Although most patients with hepatitis C presented overweight, associated with high cardiovascular risk, they also have reduced functional capacity, indicative of protein-caloric commitment. Therefore, body mass index can not be considered the only method of assessment for nutritional diagnosis of patients with liver disease. Adopting methods such as hand grip strength can be important for a better understanding of nutritional status of these

  19. Normal gait speed, grip strength and thirty seconds chair stand test among older Indians.

    Science.gov (United States)

    Gunasekaran, Venugopalan; Banerjee, Joyita; Dwivedi, Sada Nand; Upadhyay, Ashish Datt; Chatterjee, Prashun; Dey, Aparajit Ballav

    2016-01-01

    Gait speed, maximum grip strength and thirty seconds chair stand test are quick, reliable measures of functional capacity in older adults. The objective of this study was to develop normative data of the said parameters, which is lacking in older Indians. In a cross sectional study, 723 participants of ≥60 years without any morbidity, were recruited with written consent at Geriatric Medicine clinic of All India Institute of Medical sciences, New Delhi. Time taken to walk comfortably (4m) was taken as Gait speed. Maximum grip strength was assessed by using dynamometer by pressing it for 3 times in each hand, and the best of six values noted. Thirty second chair stand was assessed by the number of repetitions to stand and sit from a chair in thirty second. The Cut-off (25th percentile) of gait speed for both male and female in all age group was 0.6m/s. The Cut-off for maximum grip strength in 60-65 years, 66-70 years and >70 years for male were 20, 15 and 15 and for females were 8, 6 and 6 in kg, respectively. The Cut-off for thirty second chair stand test in 60-65 years, 66-70 years and >70 years for male were 10, 9 and 8 and for females was 8, 8 and 7, respectively. These normative data would be useful to the clinicians and researcher as Indian reference value, which is less as compared to western data. Community based multi-centre study is needed. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  20. Breakfast consumption frequency is associated with grip strength in a population of healthy Japanese adults.

    Science.gov (United States)

    Huang, C; Niu, K; Momma, H; Kobayashi, Y; Guan, L; Chujo, M; Otomo, A; Cui, Y; Nagatomi, R

    2014-06-01

    Several studies have reported that regular consumption of breakfast is associated with health benefits. However, only a few studies have examined the association between frequency of breakfast consumption and muscular function. Therefore, this study aims to investigate the association between frequency of breakfast consumption and muscle strength among apparently healthy Japanese adults. A cross-sectional study design was used. Between 2008 and 2011 in Sendai, Japan, 1415 Japanese adult employees (1069 men and 346 women) aged between 19 and 83 years participated in the study. Grip strength, as measured by a handheld digital dynamometer, was used as an indicator of muscle strength. Frequency of breakfast consumption during the previous month was assessed using a brief self-administered dietary history questionnaire, and the results were divided into three categories for analysis: low (≤2 days week⁻¹), middle (3-5 days week⁻¹) and high (≥6 days week⁻¹). Multivariate analysis was performed using analysis of covariance, with covariates mainly including socio-demographic, lifestyle-related and health-related factors. After adjusting for several potential confounders, grip strength was shown to be positively associated with breakfast consumption frequency (geometric means, 95% confidence interval (CI): low frequency, 36.2 (35.7-36.8) kg; middle frequency, 36.7 (36.0-37.5) kg; high frequency, 37.0 (36.6-37.5) kg; P for trend = 0.03). Grip strength per kilogramme body weight (kg kg⁻¹) was also positively associated with frequency of breakfast consumption (P for trend = 0.01). This cross-sectional study reveals a positive association between breakfast consumption frequency and muscle strength in apparently healthy adults. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Cross-national differences in grip strength among 50+ year old Europeans

    DEFF Research Database (Denmark)

    Andersen-Ranberg, Karen; Petersen, Inge; Frederiksen, Henrik

    2009-01-01

    Grip strength (GS) has an age- and gender-dependent decline with advancing age. One study comparing GS among extremely old show a North-South gradient with lowest GS in Italy compared to France (intermediary) and Denmark (highest) even after adjusting for confounders. As GS is associated...... with higher rates of functional decline and mortality, and thus may be used as a health indicator, it is of interest to examine whether the results on extremely old can be reproduced in a large-scale European survey. GS was measured in a cross-sectional population-based sample of 27,456 individuals aged 50...

  2. Clinical effectiveness of grip strength in predicting ambulation of elderly inpatients

    OpenAIRE

    Beseler, MR; Rubio, C; Duarte, E; Hervás, D; Guevara, MC; Giner-Pascual, M; Viosca, E

    2014-01-01

    MR Beseler,1 C Rubio,1 E Duarte,1 D Hervás,2 MC Guevara,1 M Giner-Pascual,1 E Viosca1 1Physical Medicine and Rehabilitation, La Fe Hospital, Valencia, Spain; 2Statistical Unit, La Fe Hospital, Valencia, Spain Background: Assessing the clinical effectiveness of measuring grip strength as a prognostic tool in recovering ambulation in bed-confined frail elderly patients. Methods: A prospective study was carried out with 50 elderly inpatients (mean age: 81.6 years old). Manual muscle ...

  3. Electrical conductivity measurements from the GISP2 and GRIP Greenland ice cores

    DEFF Research Database (Denmark)

    Dahl-Jensen, Dorthe; Clausen, Henrik Brink; Taylor, K. C.

    1993-01-01

    THE direct-current electrical conductivity of glacial ice depends on its acidity1-3, and can also indicate changes in climate, as ice formed in cold, dusty periods has a high concentration of alkaline dust1,4,5, which significantly reduces the conductivity6,7 compared to warmer, less dusty periods....... Here we present electrical conductivity records for the Greenland Ice Sheet Project 2 (GISP2) and Greenland Ice-core Project (GRIP) ice cores, drilled 28 km apart to enable direct comparison of the results. The upper parts of both records are consistent with previous evidence from other Greenland cores...

  4. Comparison of Initial Effect of Taping Techniqe and Counterforce Brace on Pain and Grip Strength of Patients with Lateral Epicondylitis

    Directory of Open Access Journals (Sweden)

    Ali Reza Shamsoddini

    2006-04-01

    Full Text Available Objective: In patients with lateral epicondylitis present of pain and decrease of grip strength are essential problems. Use of splint have major rule in treatment these patients that causes relief of pain and increase of grip strength. Both taping technique and counterforce brace are two methods of treatments of lateral epicondylitis patients but we were not sure which method could be more useful and Answer of this question is magor aim of this study. Materials & Methods: This study is a Quasi experimental. We selected 30 patients between 30-55 years conveniently and divided them in two groups simple randomized.  Results: In grip strength test, the average difference between two methods was t = 1/92 which showed there is not significant. So, there isn't any difference between two methods on grip strength. In assessment of pain, we tested patients in two positions: first patient's hand was in comfort position, second in which when wrist of hand was in extension position. In both of position, that average difference between two methods (first t = 3/78 and secondary t = 3/2 found to be significant. Choose of method in such treatment is considered to be important. Conclusion: taping technique is more effective than counterforce brace to relief of pain of patients with lateral epicondylitis, but in grip strength no difference between two methods.

  5. A novel mechanism of hippocampal LTD involving muscarinic receptor-triggered interactions between AMPARs, GRIP and liprin-α

    Directory of Open Access Journals (Sweden)

    Dickinson Bryony A

    2009-06-01

    Full Text Available Abstract Background Long-term depression (LTD in the hippocampus can be induced by activation of different types of G-protein coupled receptors, in particular metabotropic glutamate receptors (mGluRs and muscarinic acethycholine receptors (mAChRs. Since mGluRs and mAChRs activate the same G-proteins and isoforms of phospholipase C (PLC, it would be expected that these two forms of LTD utilise the same molecular mechanisms. However, we find a distinct mechanism of LTD involving GRIP and liprin-α. Results Whilst both forms of LTD require activation of tyrosine phosphatases and involve internalisation of AMPARs, they use different molecular interactions. Specifically, mAChR-LTD, but not mGluR-LTD, is blocked by peptides that inhibit the binding of GRIP to the AMPA receptor subunit GluA2 and the binding of GRIP to liprin-α. Thus, different receptors that utilise the same G-proteins can regulate AMPAR trafficking and synaptic efficacy via distinct molecular mechanisms. Conclusion Our results suggest that mAChR-LTD selectively involves interactions between GRIP and liprin-α. These data indicate a novel mechanism of synaptic plasticity in which activation of M1 receptors results in AMPAR endocytosis, via a mechanism involving interactions between GluA2, GRIP and liprin-α.

  6. Predicting hand function in older adults: evaluations of grip strength, arm curl strength, and manual dexterity.

    Science.gov (United States)

    Liu, Chiung-Ju; Marie, Deana; Fredrick, Aaron; Bertram, Jessica; Utley, Kristen; Fess, Elaine Ewing

    2017-08-01

    Hand function is critical for independence in activities of daily living for older adults. The purpose of this study was to examine how grip strength, arm curl strength, and manual dexterous coordination contributed to time-based versus self-report assessment of hand function in community-dwelling older adults. Adults aged ≥60 years without low vision or neurological disorders were recruited. Purdue Pegboard Test, Jamar hand dynamometer, 30-second arm curl test, Jebsen-Taylor Hand Function Test, and the Late-Life Function and Disability Instrument were administered to assess manual dexterous coordination, grip strength, arm curl strength, time-based hand function, and self-report of hand function, respectively. Eighty-four adults (mean age = 72 years) completed the study. Hierarchical multiple regressions show that older adults with better arm curl strength (β = -.25, p arm curl strength (β = .23, p Arm curl strength independently contributed to hand function in both time-based and self-report assessments, indicating that strength of extrinsic muscles of the hand are essential for hand function.

  7. Television Viewing, Walking Speed, and Grip Strength in a Prospective Cohort Study

    Science.gov (United States)

    KEEVIL, VICTORIA L.; WIJNDAELE, KATRIEN; LUBEN, ROBERT; SAYER, AVAN A.; WAREHAM, NICHOLAS J.; KHAW, KAY-TEE

    2015-01-01

    ABSTRACT Purpose Television (TV) watching is the most prevalent sedentary leisure time activity in the United Kingdom. We examined associations between TV viewing time, measured over 10 yr, and two objective measures of physical capability, usual walking speed (UWS) and grip strength. Methods Community-based participants (n = 8623; 48–92 yr old) enrolled in the European Prospective Investigation of Cancer—Norfolk study attended a third health examination (3HC, 2006–2011) for measurement of maximum grip strength (Smedley dynamometer) and UWS. TV viewing time was estimated using a validated questionnaire (n = 6086) administered during two periods (3HC, 2006–2007; 2HC, 1998–2000). Associations between physical capability and TV viewing time category (TV viewing time interactions were identified. Results Men and women who watched the least TV at the 2HC or 3HC walked at a faster usual pace than those who watched the most TV. There was no evidence of effect modification by sex (Pinteraction = 0.09), and in combined analyses, participants who watched for TV viewing time predicted UWS in older adults. More research is needed to inform public health policy and prospective associations between other measures of sedentariness, such as total sitting time or objectively measured sedentary time, and physical capability should be explored. PMID:25785826

  8. Performance of prioritized activities is not correlated with functional factors after grip reconstruction in tetraplegia.

    Science.gov (United States)

    Wangdell, Johanna; Fridén, Jan

    2011-06-01

    To investigate the correlation between perceived performance in prioritized activities and physical conditions related to grip reconstruction. Retrospective clinical outcome study. Forty-seven individuals with tetraplegia were included in the study. Each participant underwent tendon transfer surgery in the hand between November 2002 and April 2009 and had a complete 1-year follow-up. Functional characteristics and performance data were collected from our database and medical records. Patients' perceived performances in prioritized activities were recorded using the Canadian Occupational Performance Measurement. Preoperative data included age at surgery, time since injury, severity of injury, sensibility and hand dominance. At 1-year follow-up, grip strength, key pinch strength, finger pulp-to-palm distance, distance between thumb and index finger and wrist flexion were measured. Correlation rank coefficient was used to test the possible relationship between physical data and activity performance. There were improvements in both functional factors and in rated performance of prioritized activities after surgery. There was no correlation between performance change and any of the physical functions, the factors known before surgery, or the functional outcome factors. No correlation exists between a single functional outcome parameter and the patients' perceived performance of their prioritized goals in reconstructive hand surgery in tetraplegia.

  9. Hurricane Imaging Radiometer Wind Speed and Rain Rate Retrievals during the 2010 GRIP Flight Experiment

    Science.gov (United States)

    Sahawneh, Saleem; Farrar, Spencer; Johnson, James; Jones, W. Linwood; Roberts, Jason; Biswas, Sayak; Cecil, Daniel

    2014-01-01

    Microwave remote sensing observations of hurricanes, from NOAA and USAF hurricane surveillance aircraft, provide vital data for hurricane research and operations, for forecasting the intensity and track of tropical storms. The current operational standard for hurricane wind speed and rain rate measurements is the Stepped Frequency Microwave Radiometer (SFMR), which is a nadir viewing passive microwave airborne remote sensor. The Hurricane Imaging Radiometer, HIRAD, will extend the nadir viewing SFMR capability to provide wide swath images of wind speed and rain rate, while flying on a high altitude aircraft. HIRAD was first flown in the Genesis and Rapid Intensification Processes, GRIP, NASA hurricane field experiment in 2010. This paper reports on geophysical retrieval results and provides hurricane images from GRIP flights. An overview of the HIRAD instrument and the radiative transfer theory based, wind speed/rain rate retrieval algorithm is included. Results are presented for hurricane wind speed and rain rate for Earl and Karl, with comparison to collocated SFMR retrievals and WP3D Fuselage Radar images for validation purposes.

  10. Food-rewarded conditioning and neurophysiological analysis of cheliped gripping behavior in crayfish.

    Science.gov (United States)

    Takahashi, Naomi; Takahata, Masakazu

    2017-10-15

    Animals act on their environment to intentionally manipulate it with a defined purpose. This behavior generally needs a special organ suited for the purpose and a highly complex neural mechanism to perform voluntary motor control. Crustaceans with a pair of chelipeds show various manipulative behavior for dietary, exploratory, and reproductive purposes, but the neuronal mechanism underlying the cheliped manipulative behavior has not been clarified yet. In the present study, we trained crayfish Procambarus clarkii to perform a cheliped manipulative task by a newly developed operant paradigm in which animals gripped a specific object for food reward when a visual cue was presented. Animals were then tethered in an operant chamber during the task to enable reliable physiological recordings from the central nervous system. Neural activities descending from the brain were recorded extracellularly from the connective nerves between the brain and the subesophageal ganglion in the trained animals. We found those units showing spike activities that were significantly correlated with cheliped muscle activities, but not with strict timing of visual cue presentation. Although we could not test if those descending activities were necessary or sufficient for initiating the cheliped action by their selective stimulation, the present findings suggest that neural activities for controlling operant gripping behavior are formulated in the brain rather than in the subesophageal ganglion where cheliped motoneurons are present and visual information is transmitted through the brain. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Development of Hand Grip Assistive Device Control System for Old People through Electromyography (EMG Signal Acquisitions

    Directory of Open Access Journals (Sweden)

    Khamis Herman

    2017-01-01

    Full Text Available The hand grip assistive device is a glove to assist old people who suffer from hand weakness in their daily life activities. The device earlier control system only use simple on and off switch. This required old people to use both hand to activate the device. The new control system of the hand grip assistive device was developed to allow single hand operation for old people. New control system take advantages of electromyography (EMG and flex sensor which was implemented to the device. It was programmed into active and semi-active mode operation. EMG sensors were placed on the forearm to capture EMG signal of Flexor Digitorum Profundus muscle to activate the device. Flex sensor was used to indicate the finger position and placed on top of the finger. The signal from both sensors then used to control the device. The new control system allowed single hand operation and designed to prevent user from over depended on the device by activating it through moving their fingers.

  12. Modified forelimb grip strength test detects aging-associated physiological decline in skeletal muscle function in male mice.

    Science.gov (United States)

    Takeshita, Hikari; Yamamoto, Koichi; Nozato, Satoko; Inagaki, Tadakatsu; Tsuchimochi, Hirotsugu; Shirai, Mikiyasu; Yamamoto, Ryohei; Imaizumi, Yuki; Hongyo, Kazuhiro; Yokoyama, Serina; Takeda, Masao; Oguro, Ryosuke; Takami, Yoichi; Itoh, Norihisa; Takeya, Yasushi; Sugimoto, Ken; Fukada, So-Ichiro; Rakugi, Hiromi

    2017-02-08

    The conventional forelimb grip strength test is a widely used method to assess skeletal muscle function in rodents; in this study, we modified this method to improve its variability and consistency. The modified test had lower variability among trials and days than the conventional test in young C57BL6 mice, especially by improving the variabilities in male. The modified test was more sensitive than the conventional test to detect a difference in motor function between female and male mice, or between young and old male mice. When the modified test was performed on male mice during the aging process, reduction of grip strength manifested between 18 and 24 months of age at the group level and at the individual level. The modified test was similar to the conventional test in detecting skeletal muscle dysfunction in young male dystrophic mice. Thus, the modified forelimb grip strength test, with its improved validity and reliability may be an ideal substitute for the conventional method.

  13. [Evaluation of grip strength in normal and obese Wistar rats submitted to swimming with overload after median nerve compression].

    Science.gov (United States)

    Coradinia, Josinéia Gresele; Kakihata, Camila Mayumi Martin; Kunz, Regina Inês; Errero, Tatiane Kamada; Bonfleur, Maria Lúcia; Bertolini, Gladson Ricardo Flor

    2015-01-01

    To verify the functionality through muscle grip strength in animals with obesity induced by monosodium glutamate (MSG) and in control animals, which suffered compression of the right median nerve, and treated with swimming with overload. During the first five days of life, neonatal Wistar rats received subcutaneous injections of MSG. The control group received a hypertonic saline solution. Forty-eight rats were divided into six groups: G1 (control); G2 (control + injury); G3 (control + injury + swimming); G4 (obese); G5 (obese + injury); G6 (obese + injury + swimming). The animals in groups G2, G3, G5 and G6 were submitted to compression of the median nerve and G3 and G6 groups were treated, after injury, with swimming exercise with load for three weeks. The swimming exercise had a progressive duration, according to the week, of 20, 30 and 40minutes. Muscle strength was assessed using a grip strength meter preoperatively and on the 3rd, 7th, 14th and 21st days after surgery. The results were expressed and analyzed using descriptive and inferential statistics. When the grip strength was compared among assessments regardless of group, in the second assessment the animals exhibited lower grip strength. G1 and G4 groups had greater grip strength, compared to G2, G3, G4 and G6. The swimming exercise with overload has not been effective in promoting improvement in muscle grip strength after compression injury of the right median nerve in control and in obese-MSG rats. Copyright © 2013 Elsevier Editora Ltda. All rights reserved.

  14. Modeling the Maturation of Grip Selection Planning and Action Representation: Insights from Typical and Atypical Motor Development.

    Directory of Open Access Journals (Sweden)

    Ian eFuelscher

    2016-02-01

    Full Text Available We investigated the purported association between developmental changes in grip selection planning and improvements in an individual’s capacity to represent action at an internal level (i.e., motor imagery. Participants were groups of healthy children aged 6-7 years and 8-12 years respectively, while a group of adolescents (13-17 years and adults (18-34 years allowed for consideration of childhood development in the broader context of motor maturation. A group of children aged 8-12 years with probable DCD (pDCD was included as a reference group for atypical motor development. Participants’ proficiency to generate and/or engage internal action representations was inferred from performance on the hand rotation task, a well-validated measure of motor imagery. A grip selection task designed to elicit the end-state comfort (ESC effect provided a window into the integrity of grip selection planning. Consistent with earlier accounts, the efficiency of grip selection planning followed a non-linear developmental progression in neurotypical individuals. As expected, analysis confirmed that these developmental improvements were predicted by an increased capacity to generate and/or engage internal action representations. The profile of this association remained stable throughout the (typical developmental spectrum. These findings are consistent with computational accounts of action planning that argue that internal action representations are associated with the expression and development of grip selection planning across typical development. However, no such association was found for our sample of children with pDCD, suggesting that individuals with atypical motor skill may adopt an alternative, sub-optimal strategy to plan their grip selection compared to their same-age control peers.

  15. GRIP: A web-based system for constructing Gold Standard datasets for protein-protein interaction prediction

    Directory of Open Access Journals (Sweden)

    Zheng Huiru

    2009-01-01

    Full Text Available Abstract Background Information about protein interaction networks is fundamental to understanding protein function and cellular processes. Interaction patterns among proteins can suggest new drug targets and aid in the design of new therapeutic interventions. Efforts have been made to map interactions on a proteomic-wide scale using both experimental and computational techniques. Reference datasets that contain known interacting proteins (positive cases and non-interacting proteins (negative cases are essential to support computational prediction and validation of protein-protein interactions. Information on known interacting and non interacting proteins are usually stored within databases. Extraction of these data can be both complex and time consuming. Although, the automatic construction of reference datasets for classification is a useful resource for researchers no public resource currently exists to perform this task. Results GRIP (Gold Reference dataset constructor from Information on Protein complexes is a web-based system that provides researchers with the functionality to create reference datasets for protein-protein interaction prediction in Saccharomyces cerevisiae. Both positive and negative cases for a reference dataset can be extracted, organised and downloaded by the user. GRIP also provides an upload facility whereby users can submit proteins to determine protein complex membership. A search facility is provided where a user can search for protein complex information in Saccharomyces cerevisiae. Conclusion GRIP is developed to retrieve information on protein complex, cellular localisation, and physical and genetic interactions in Saccharomyces cerevisiae. Manual construction of reference datasets can be a time consuming process requiring programming knowledge. GRIP simplifies and speeds up this process by allowing users to automatically construct reference datasets. GRIP is free to access at http://rosalind.infj.ulst.ac.uk/GRIP/.

  16. GRIP: A web-based system for constructing Gold Standard datasets for protein-protein interaction prediction.

    Science.gov (United States)

    Browne, Fiona; Wang, Haiying; Zheng, Huiru; Azuaje, Francisco

    2009-01-26

    Information about protein interaction networks is fundamental to understanding protein function and cellular processes. Interaction patterns among proteins can suggest new drug targets and aid in the design of new therapeutic interventions. Efforts have been made to map interactions on a proteomic-wide scale using both experimental and computational techniques. Reference datasets that contain known interacting proteins (positive cases) and non-interacting proteins (negative cases) are essential to support computational prediction and validation of protein-protein interactions. Information on known interacting and non interacting proteins are usually stored within databases. Extraction of these data can be both complex and time consuming. Although, the automatic construction of reference datasets for classification is a useful resource for researchers no public resource currently exists to perform this task. GRIP (Gold Reference dataset constructor from Information on Protein complexes) is a web-based system that provides researchers with the functionality to create reference datasets for protein-protein interaction prediction in Saccharomyces cerevisiae. Both positive and negative cases for a reference dataset can be extracted, organised and downloaded by the user. GRIP also provides an upload facility whereby users can submit proteins to determine protein complex membership. A search facility is provided where a user can search for protein complex information in Saccharomyces cerevisiae. GRIP is developed to retrieve information on protein complex, cellular localisation, and physical and genetic interactions in Saccharomyces cerevisiae. Manual construction of reference datasets can be a time consuming process requiring programming knowledge. GRIP simplifies and speeds up this process by allowing users to automatically construct reference datasets. GRIP is free to access at http://rosalind.infj.ulst.ac.uk/GRIP/.

  17. Visual and somatosensory information about object shape control manipulative fingertip forces.

    Science.gov (United States)

    Jenmalm, P; Johansson, R S

    1997-06-01

    We investigated the importance of visual versus somatosensory information for the adaptation of the fingertip forces to object shape when humans used the tips of the right index finger and thumb to lift a test object. The angle of the two flat grip surfaces in relation to the vertical plane was changed between trials from -40 to 30 degrees. At 0 degrees the two surfaces were parallel, and at positive and negative angles the object tapered upward and downward, respectively. Subjects automatically adapted the balance between the horizontal grip force and the vertical lift force to the object shape and thereby maintained a rather constant safety margin against frictional slips, despite the huge variation in finger force requirements. Subjects used visual cues to adapt force to object shape parametrically in anticipation of the force requirements imposed once the object was contacted. In the absence of somatosensory information from the digits, sighted subjects still adapted the force coordination to object shape, but without vision and somatosensory inputs the performance was severely impaired. With normal digital sensibility, subjects adapted the force coordination to object shape even without vision. Shape cues obtained by somatosensory mechanisms were expressed in the motor output about 0. 1 sec after contact. Before this point in time, memory of force coordination used in the previous trial controlled the force output. We conclude that both visual and somatosensory inputs can be used in conjunction with sensorimotor memories to adapt the force output to object shape automatically for grasp stability.

  18. Labor Force

    Science.gov (United States)

    Occupational Outlook Quarterly, 2012

    2012-01-01

    The labor force is the number of people ages 16 or older who are either working or looking for work. It does not include active-duty military personnel or the institutionalized population, such as prison inmates. Determining the size of the labor force is a way of determining how big the economy can get. The size of the labor force depends on two…

  19. The JPL GRIP Portal - Serving Near Real-time Observation and Model Forecast for Hurricane Study

    Science.gov (United States)

    Li, P.; Hristova-Veleva, S. M.; Turk, F. J.; Vu, Q.; Knosp, B. W.; Lambrigtsen, B.; Poulsen, W. L.; Shen, T. J.; Licata, S. J.

    2010-12-01

    NASA conducted a field experiment, the Genesis and Rapid Intensification Processes (GRIP), in the summer of 2010 to better understand how tropical storms form and develop into major hurricanes. The DC-8 aircraft and the Global Hawk Unmanned Airborne System (UAS) were deployed loaded with instruments for measurements including lightning, temperature, 3D wind, precipitation, liquid and ice water contents, aerosol and cloud profiles. JPL created a web portal to collect, process and display both the satellite and the airborne observations in near real-time (NRT) and integrated then with the hurricane forecast models. The objective of the JPL GRIP portal is to provide environmental context and temporal continuity for the field campaign observations to help: (1) mission planning, (2) understanding of the physical processes, and (3) improving models through validation and data assimilation. Built on top of the JPL Tropical Cyclone Information System (TCIS) infrastructure, we developed a GRIP portal presenting a near-real time (NRT) basin-scale view of the atmospheric and surface conditions over the Atlantic, characterizing large-scale and storm-scale processes, as depicted by satellites and models. Using Google Earth embedded in the web browser and two independent calendars, we provide 3D visualization of a comprehensive collection of observations and model results as overlapping image overlays, wind vectors, curtain plots, or clickable tracks. We also provide Google Earth time animations of multiple data and model variables. In the portal, we offer more than two dozen NRT satellite products from a wide variety of instruments, model forecasts from four large-scale models (i.e., NOGAPS, GFS, ECMWF, and UKMET), and the best tracks and the forecast tracks from National Hurricane Center’s ATCF models. As they become available, we also display the airborne observations from HAMSR, APR2 and Dropsonde. It is a great challenge to set up a reliable infrastructure to collect data

  20. The development of a methodology to determine the relationship in grip size and pressure to racket head speed in a tennis forehand stroke

    DEFF Research Database (Denmark)

    Christensen, Jonas; Rasmussen, John; Halkon, Ben

    2016-01-01

    and kinematic contribution of the body segments in the upper trunk translational and angular velocities. Two Babolat Pure Storm GT rackets, with grip sizes 2 and 4 respectively, were used with Tekscan 9811E pressure sensors applied to the handles to examine pressure distribution during the stroke. Upper body......This study developed a methodology to examine the effects of grip size and grip firmness on the kinematic contribution of angular velocity (KCAV) to the generation of racket head speed during a topspin tennis forehand. The KCAV is subdivided into kinematic contribution of joint angular velocity...... in a significant (p2 compared to grip size 4. A trend in negative linear relationships was found between upper trunk and shoulder joint in KCAV across conditions. Using the smaller grip also led to a trend in negative linear relationship between shoulder...

  1. Dispersion Forces

    CERN Document Server

    Buhmann, Stefan Yoshi

    2012-01-01

    In this book, a modern unified theory of dispersion forces on atoms and bodies is presented which covers a broad range of advanced aspects and scenarios. Macroscopic quantum electrodynamics is shown to provide a powerful framework for dispersion forces which allows for discussing general properties like their non-additivity and the relation between microscopic and macroscopic interactions. It is demonstrated how the general results can be used to obtain dispersion forces on atoms in the presence of bodies of various shapes and materials. Starting with a brief recapitulation of volume I, this volume II deals especially with bodies of irregular shapes, universal scaling laws, dynamical forces on excited atoms, enhanced forces in cavity quantum electrodynamics, non-equilibrium forces in thermal environments and quantum friction. The book gives both the specialist and those new to the field a thorough overview over recent results in the field. It provides a toolbox for studying dispersion forces in various contex...

  2. Wrist extension strength required for power grip: a study using a radial nerve block model.

    Science.gov (United States)

    Suzuki, T; Kunishi, T; Kakizaki, J; Iwakura, N; Takahashi, J; Kuniyoshi, K

    2012-06-01

    The aim of this study was to investigate the correlation of wrist extension strength (WES) and grip strength (GS) using a radial nerve block, and to determine the WES required to prevent the "wrist flexion phenomenon" (antagonistic WES) when making a fist. We tested 14 arms in seven healthy males. WES and GS were measured before blocking as standard WES and standard GS. All participants then had radial nerve blocks with mepivacaine hydrochloride. During the recovery process from radial nerve blockade, WES and GS were recorded every 5 minutes. There was a very strong correlation between WES and GS (p < 0.0001). The mean antagonistic WES was 51% of standard WES, and the mean GS, recorded at the same time, was 66% of standard GS.

  3. Juliane's speech: Knut Hamsun's Play In the Grip of Life (Livet i vold

    Directory of Open Access Journals (Sweden)

    Monika Zagar

    2003-08-01

    Full Text Available My article will present an examination of interactional styles in dialogues created by Knut Hamsun in his 1910 play In the Grip of Life (Livet i vold. Hamsun equipped his protagonists with a particular speech. The point of the analysis is to investigate how Hamsun fleshed out his protagonists' speech styles, what he deemed as the most suitable and appropriate speech for women and men, and how he lets them transgress it. In fact, Hamsun uses transgression of the traditional rules of gender communication as his creative technique. Following Weber-Knapp's strategy, my analysis will focus on the following: length and frequency of speech contributions, interruptions, and initiating and responding utterances

  4. Grip strength dynamometry: reliability and validity for adults with upper limb burns.

    Science.gov (United States)

    Clifford, Merci S; Hamer, Peter; Phillips, Michael; Wood, Fiona M; Edgar, Dale W

    2013-11-01

    Upper limb (UL) burns can result in significant loss of strength and physical function. The aim of this study was to establish the reliability and validity of grip strength dynamometry (GSD) for measuring burn-affected UL strength over time. A retrospective sample of adult participants (n=89) with UL burns was obtained from Royal Perth Hospital. Data were compiled from assessments conducted at discharge, one, three, six and 12 months afer burn. Within-session reliability and validity was examined through multivariable analyses. GSD demonstrated within-session reliability for all investigated timepoints (ICC's≥0.87, pdynamometry is a reliable and valid outcome measure for measuring burn-affected UL strength from one month to one year after burn. Copyright © 2013 Elsevier Ltd and ISBI. All rights reserved.

  5. A single magnetic nanocomposite cilia force sensor

    KAUST Repository

    Alfadhel, Ahmed

    2016-04-20

    The advancements in fields like robotics and medicine continuously require improvements of sensor devices and more engagement of cooperative sensing technologies. For example, instruments such as tweezers with sensitive force sensory heads could provide the ability to sense a variety of physical quantities in real time, such as the amount and direction of the force applied or the texture of the gripped object. Force sensors with such abilities could be great solutions toward the development of smart surgical tools. In this work, a unique force sensor that can be integrated at the tips of robotic arms or surgical tools is reported. The force sensor consists of a single bioinspired, permanent magnetic and highly elastic nanocomposite cilia integrated on a magnetic field sensing element. The nanocomposite is prepared from permanent magnetic nanowires incorporated into the highly elastic polydimethylsiloxane. We demonstrate the potential of this concept by performing several experiments to show the performance of the force sensor. The developed sensor element has a 200 μm in diameter single cilium with 1:5 aspect ratio and shows a detection range up to 1 mN with a sensitivity of 1.6 Ω/mN and a resolution of 31 μN. The simple fabrication process of the sensor allows easy optimization of the sensor performance to meet the needs of different applications.

  6. Coefficient of friction of dry slash pine and southern red oak on three tension-grip facings

    Science.gov (United States)

    Truett J. Lemoine; Peter Koch

    1974-01-01

    A urethane material proved to have nine times higher static friction coefficient (0.9) than smooth steel (0.1) on radial and tangential wood surfaces pulled parallel to the grain. It is probably superior to 220-grit garnet paper or sand coatings for tension-grip facings in lumber testing machines.

  7. Physical function, grip strength and frailty in people living with HIV in sub-Saharan Africa: systematic review.

    Science.gov (United States)

    Bernard, Charlotte; Dabis, François; de Rekeneire, Nathalie

    2017-05-01

    To present the current knowledge on physical function, grip strength and frailty in HIV-infected patients living in sub-Saharan Africa, where the phenomenon is largely underestimated. A systematic search was conducted on MEDLINE, Scopus and African Index Medicus. We reviewed articles on sub-Saharan African people living with HIV (PLHIV) >18 years old, published until November 2016. Of 537 articles, 12 were conducted in six African countries and included in this review. Five articles reported information on functional limitation and one on disability. Two of these five articles reported functional limitation (low gait speed) in PLHIV. Disability was observed in 27% and 3% of PLHIV living in rural and urban places, respectively. Two of three studies reporting grip strength reported lower grip strength (nearly 4 kg) in PLHIV in comparison with uninfected patients. One study reported that PLHIV were more likely to be frail than HIV-uninfected individuals (19.4% vs. 13.3%), whereas another reported no statistical difference. Decline in physical function, grip strength and frailty are now part of the burden of PLHIV living in SSA countries, but current data are insufficient to characterise the real public health dimension of these impairments. Further studies are needed to depict this major public health challenge. As this is likely to contribute to a significant burden on the African healthcare systems and human resources in the near future, a holistic care approach should be developed to inform guidelines. © 2017 John Wiley & Sons Ltd.

  8. The Effect of Repetitive Rhythmic Precision Grip Task-Oriented Rehabilitation in Chronic Stroke Patients: A Pilot Study

    Science.gov (United States)

    Dispa, Delphine; Lejeune, Thierry; Thonnard, Jean-Louis

    2013-01-01

    Most chronic stroke patients present with difficulty in the manipulation of objects. The aim of this study was to test whether an intensive program of precision grip training could improve hand functioning of patients at more than 6 months after a stroke. This was a cross-over study; hence, at inclusion, the patients were randomly divided into two…

  9. Grip-Pattern Verification for Smart Gun Based on Maximum-Pairwise Comparison and Mean-Template Comparison

    NARCIS (Netherlands)

    Shang, X.; Veldhuis, Raymond N.J.

    2008-01-01

    In our biometric verification system of a smart gun, the rightful user of a gun is authenticated by grip-pattern recognition. In this work verification will be done using two types of comparison methods, respectively. One is mean-template comparison, where the matching score between a test image and

  10. Isometric hand grip strength measured by the Nintendo Wii Balance Board - a reliable new method.

    Science.gov (United States)

    Blomkvist, A W; Andersen, S; de Bruin, E D; Jorgensen, M G

    2016-02-03

    Low hand grip strength is a strong predictor for both long-term and short-term disability and mortality. The Nintendo Wii Balance Board (WBB) is an inexpensive, portable, wide-spread instrument with the potential for multiple purposes in assessing clinically relevant measures including muscle strength. The purpose of the study was to explore intrarater reliability and concurrent validity of the WBB by comparing it to the Jamar hand dynamometer. Intra-rater test-retest cohort design with randomized validity testing on the first session. Using custom WBB software, thirty old adults (69.0 ± 4.2 years of age) were studied for reproducibility and concurrent validity compared to the Jamar hand dynamometer. Reproducibility was tested for dominant and non-dominant hands during the same time-of-day, one week apart. Intraclass correlation coefficient (ICC) and standard error of measurement (SEM) and limits of agreement (LOA) were calculated to describe relative and absolute reproducibility respectively. To describe concurrent validity, Pearson's product-moment correlation and ICC was calculated. Reproducibility was high with ICC values of >0.948 across all measures. Both SEM and LOA were low (0.2-0.5 kg and 2.7-4.2 kg, respectively) in both the dominant and non-dominant hand. For validity, Pearson correlations were high (0.80-0.88) and ICC values were fair to good (0.763-0.803). Reproducibility for WBB was high for relative measures and acceptable for absolute measures. In addition, concurrent validity between the Jamar hand dynamometer and the WBB was acceptable. Thus, the WBB may be a valid instrument to assess hand grip strength in older adults.

  11. Synaptic and functional linkages between spinal premotor interneurons and hand-muscle activity during precision grip

    Directory of Open Access Journals (Sweden)

    Tomohiko eTakei

    2013-04-01

    Full Text Available Grasping is a highly complex movement that requires the coordination of a number of hand joints and muscles. Previous studies showed that spinal premotor interneurons (PreM-INs in the primate cervical spinal cord have divergent synaptic effects on hand motoneurons and that they might contribute to hand-muscle synergies. However, the extent to which these PreM-IN synaptic connections functionally contribute to modulating hand-muscle activity is not clear. In this paper, we explored the contribution of spinal PreM-INs to hand-muscle activation by quantifying the synaptic linkage (SL and functional linkage (FL of the PreM-INs with hand-muscle activities. The activity of 23 PreM-INs was recorded from the cervical spinal cord (C6–T1, with EMG signals measured simultaneously from hand and arm muscles in two macaque monkeys performing a precision grip task. Spike-triggered averages (STAs of rectified EMGs were compiled for 456 neuron–muscle pairs; 63 pairs showed significant post-spike effects (i.e., SL. Conversely, 231 of 456 pairs showed significant cross-correlations between the IN firing rate and rectified EMG (i.e., FL. Importantly, a greater proportion of the neuron–muscle pairs with SL showed FL (43/63 pairs, 68% compared with the pairs without SL (203/393, 52%, and the presence of SL was significantly associated with that of FL. However, a significant number of pairs had SL without FL (SL∩!FL, n = 20 or FL without SL (!SL∩FL, n = 203, and the proportions of these incongruities exceeded the number expected by chance. These results suggested that spinal PreM-INs function to significantly modulate hand-muscle activity during precision grip, but the contribution of other neural structures is also needed to recruit an adequate combination of hand-muscle motoneurons.

  12. Relationship of kimono grip strength tests with isokinetic parameters in jiu-jitsu athletes

    Directory of Open Access Journals (Sweden)

    Bruno Follmer

    2015-09-01

    Full Text Available DOI: http://dx.doi.org/10.5007/1980-0037.2015v17n5p575   The aim of the present study was to correlate two specific kimono grip strength tests (KGST with elbow flexors and extensors isokinetic parameters in Jiu Jitsu (JJ athletes. Fifteen male JJ athletes, from blue to black belt, participated in the study. The two KGST were: maximum static lift (MSL, and maximum number of repetitions (MNR, both gripping a kimono wrapped around a bar. Isokinetic tests consisted of three sets of 5 s elbow flexion-extension maximum voluntary isometric contraction (MVIC in three different elbow angles (45, 90 and 120°, and two sets of five concentric-eccentric elbow flexion-extension maximum dynamic contractions at 60°·s-1, to determine peak torque (PT. Absolute values of MSL and MNR were 41.4 ± 16.2 s and 10 ± 5 reps, respectively, and tests presented a nearly perfect correlation among them (r=0.91; p<0.001. Significant correlations were reported between MNR and PT during MVIC for elbow flexors at 45° and 90°, elbow extensors at 120°, and during concentric and eccentric dynamic contractions for both flexors and extensors. Therefore, KGST were highly correlated with isokinetic parameters, and were nearly perfect correlated among them, supporting that one of the tests could be chosen to evaluate strength in JJ athletes. The MNR test presented apparently higher levels of relation than MSL, and provided significant information about muscle strength endurance in JJ athletes

  13. Forecasts: uncertain, inaccurate and biased?

    DEFF Research Database (Denmark)

    Nicolaisen, Morten Skou; Ambrasaite, Inga; Salling, Kim Bang

    2012-01-01

    Cost Benefit Analysis (CBA) is the dominating methodology for appraisal of transport infrastructure projects across the globe. In order to adequately assess the costs and benefits of such projects two types of forecasts are crucial to the validity of the appraisal. First are the forecasts of cons....... It is recommended that more attention is given to monitoring completed projects so future forecasts can benefit from better data availability through systematic ex-post evaluations, and an example of how to utilize such data in practice is presented....

  14. Grip strength measurement for frailty assessment in patients with vascular disease and associations with comorbidity, cardiac risk, and sarcopenia.

    Science.gov (United States)

    Reeve, Thomas E; Ur, Rebecca; Craven, Timothy E; Kaan, James H; Goldman, Matthew P; Edwards, Matthew S; Hurie, Justin B; Velazquez-Ramirez, Gabriela; Corriere, Matthew A

    2017-12-21

    Frailty is associated with adverse events, length of stay, and nonhome discharge after vascular surgery. Frailty measures based on walking-based tests may be impractical or invalid for patients with walking impairment from symptoms or sequelae of vascular disease. We hypothesized that grip strength is associated with frailty, comorbidity, and cardiac risk among patients with vascular disease. Dominant hand grip strength was measured during ambulatory clinic visits among patients with vascular disease (abdominal aortic aneurysm [AAA], carotid stenosis, and peripheral artery disease [PAD]). Frailty prevalence was defined on the basis of the 20th percentile of community-dwelling population estimates adjusted for age, gender, and body mass index. Associations between grip strength, Charlson Comorbidity Index (CCI), Revised Cardiac Risk Index (RCRI), and sarcopenia (based on total psoas area for patients with cross-sectional abdominal imaging) were evaluated using linear and logistic regression. Grip strength was measured in 311 participants; all had sufficient data for CCI calculation, 217 (69.8%) had sufficient data for RCRI, and 88 (28.3%) had cross-sectional imaging permitting psoas measurement. Eighty-six participants (27.7%) were categorized as frail on the basis of grip strength. Frailty was associated with CCI (odds ratio, 1.86; 95% confidence interval, 1.34-2.57; P = .0002) in the multivariable model. Frail participants also had a higher average number of RCRI components vs nonfrail patients (mean ± standard deviation, 1.8 ± 0.8 for frail vs 1.5 ± 0.7 for nonfrail; P = .018); frailty was also associated with RCRI in the adjusted multivariable model (odds ratio, 1.75; 95% confidence interval, 1.16-2.64; P = .008). Total psoas area was lower among patients categorized as frail vs nonfrail on the basis of grip strength (21.0 ± 6.6 vs 25.4 ± 7.4; P = .010). Each 10 cm 2 increase in psoas area was associated with a 5.7 kg increase in grip strength

  15. Reference values of hand-grip dynamometry and the relationship between low strength and mortality in older Chileans.

    Science.gov (United States)

    Lera, Lydia; Albala, Cecilia; Leyton, Bárbara; Márquez, Carlos; Angel, Bárbara; Saguez, Rodrigo; Sánchez, Hugo

    2018-01-01

    This study was aimed to set reference values of hand-grip strength by age and sex and validate cut points for risk of functional limitation and mortality in older Chileans. This was a pooled analysis of four studies including 6,426 people ≥60 years of nondependent community-dwelling Chileans. After exclusion criteria, the final sample included 5,250 subjects, from whom 2,193 were followed to study all-cause mortality associated with low hand-grip strength. Face-to-face interviews registering sociodemographic characteristics, self-reported chronic diseases, and functional limitations were conducted. Anthropometric measurements and observed mobility were performed by trained professionals. Hand-grip strength was measured with a hand dynamometer T-18 (Country Technology, Inc.) before 2008 or with JAMAR brand from 2008 onwards. Percentiles were calculated through descriptive analysis and quantile regression models for specific groups of age and sex. Adjusted Cox regression hazard models for mortality risk according to low dynamometry condition and covariates were developed. We deliver reference values of hand-grip strength for older Chileans proposing the 25th percentile as the cut-off point for low dynamometry risk: men ≤27 kg, women ≤15 kg. Low hand-grip strength was associated with Instrumental Activities of Daily Living limitations ( p =0.001), and altered physical performance evaluated through the Timed Up and Go test ( p =0.0001), grasping ( p =0.001), bending ( p dynamometry validated for the older Chileans allow the incorporation in the geriatric evaluation in primary health care of an easy-to-use, inexpensive indicator to identify older adults at risk of sarcopenia, frailty, and dismobility. In addition this also helps to optimize the evaluation of intervention strategies focused on the maintenance of functionality.

  16. Forced marriage.

    Science.gov (United States)

    2007-06-01

    Guidelines to help A&E staff and other healthcare professionals who suspect cases of forced marriage were launched this month by the government. The guidelines provide practical advice on how to recognise the warning signs, and what to do if patients disclose that they have been, or are about to be, forced to marry. The guidelines, Dealing with Cases of Forced Marriage, are available at www.fco.gov.uk/forcedmarriage.

  17. Design of a microelectromechanical systems microgripper with integrated electrothermal actuator and force sensor

    Directory of Open Access Journals (Sweden)

    Sijie Yang

    2016-10-01

    Full Text Available This article presents the conceptual design of a novel compliant microelectromechanical systems (MEMS-based gripper with integrated electrothermal actuator and electrothermal force sensor. By this design solution, the device possesses some unique characteristics including a small and compact footprint size, and a large driving force by the thermal actuator. Owing to the use of a compliant rotational bearing, a large gripping range is obtained. The sensing arm has a capability of detecting the force transmitted from the left arm so as to prevent the damage of the grasped object. Analytical models are developed to evaluate the statics and dynamics performance of the gripper. Simulation results show that the thermal actuator produces sufficient gripping force to execute the gripping operation with a range of 80 µm under a low input voltage of 6 V. Moreover, the results of the established theoretical models match well with the finite element analysis (FEA simulation results, which verifies the feasibility of the proposed gripper design.

  18. Effect of Insoles with a Toe-Grip Bar on Toe Function and Standing Balance in Healthy Young Women: A Randomized Controlled Trial

    Directory of Open Access Journals (Sweden)

    Hideki Nakano

    2017-01-01

    Full Text Available Objective. The aim of this randomized controlled study was to investigate the effects of insoles with a toe-grip bar on toe function and standing balance in healthy young women. Methods. Thirty female subjects were randomly assigned to an intervention group or a control group. The intervention group wore shoes with insoles with a toe-grip bar. The control group wore shoes with general insoles. Both groups wore the shoes for 4 weeks, 5 times per week, 9 hours per day. Toe-grip strength, toe flexibility, static balance (total trajectory length and envelope area of the center of pressure, and dynamic balance (functional reach test were measured before and after the intervention. Results. Significant interactions were observed for toe-grip strength and toe flexibility (F=12.53, p<0.01; F=5.84, p<0.05, resp., with significant improvement in the intervention group compared with that in the control group. Post hoc comparisons revealed that both groups showed significant improvement in toe-grip strength (p<0.01 and p<0.05, resp., with higher benefits observed for the intervention group (p<0.01. Conversely, no significant interaction was observed in the total trajectory length, envelope area, and functional reach test. Conclusions. This study suggests that insoles with a toe-grip bar contribute to improvements in toe-grip strength and toe flexibility in healthy young women.

  19. Different forces

    CERN Multimedia

    1982-01-01

    The different forces, together with a pictorial analogy of how the exchange of particles works. The table lists the relative strength of the couplings, the quanta associated with the force fields and the bodies or phenomena in which they have a dominant role.

  20. The forces behind the words: development of the kinetic pen.

    Science.gov (United States)

    Hooke, Alexander W; Park, Jaebum; Shim, Jae Kun

    2008-01-01

    This paper describes the creation of a Kinetic Pen capable of measuring the six-component force and torque that each of four individual contacts applies to the pen during writing. This was done by staggering the mounting of the four sensors along the long axis of the pen and having an extended arm run from the sensor to the grip site, preventing a clustering of the sensors where the digit tips meet while grasping. The implications of this tool allow handwriting studies to be expanded from two-dimensional pen-tip kinematics to three-dimensional dynamics at each contact point between the hand and pen.

  1. Task-dependent changes of motor cortical network excitability during precision grip compared to isolated finger contraction

    DEFF Research Database (Denmark)

    Kouchtir-Devanne, Nezha; Capaday, Charles; Cassim, François

    2012-01-01

    The purpose of this study was to determine whether task-dependent differences in corticospinal pathway excitability occur in going from isolated contractions of the index finger to its coordinated activity with the thumb. Focal transcranial magnetic stimulation (TMS) was used to measure input......-output (I/O) curves—a measure of corticospinal pathway excitability—of the contralateral first dorsal interosseus (FDI) muscle in 21 healthy subjects performing two isometric motor tasks: index abduction and precision grip. The level of FDI electromyographic (EMG) activity was kept constant across tasks...... between the two tasks. Short- and long-latency intracortical inhibitions (SICI and LICI, respectively) were also measured in each task. Both measures of inhibition decreased during precision grip compared with the isolated contraction. The results demonstrate that the motor cortical circuits controlling...

  2. Experimental Studies of a Series of High Strength Friction Grip Bolted Joints

    Directory of Open Access Journals (Sweden)

    M. Budescu

    2005-01-01

    Full Text Available The performed tests intended to establish the necessary conditions for surfaces of the assemblage elements in contact with the KB, so as, by connecting them using the HSFG (High Strength Friction Grip bolts, to ensure the necessary frictional resistance. The tests have performed using 2.5mm thickness KB250 thin – walled profiles. This minimum thickness is often used for structural elements in this constructive system. The KONTIBEAM system is primarily made of two galvanized sheet profiles so denominated as “KB”, which are joined by means of steel sheets, (usually of 10 mm thickness, placed in – between them. Connecting this assembly (KB’s and connectors is done by using M20 bolts put in Ø 22 holes, which work in friction with two contact planes. The tested joints are connected by means of 8.8 class HSFG bolts. The connecting elements for tested KB’s have been manufactured with two types of prepared surfaces: (i rough (sandblasted and (ii covered with a zincamid film. The main conclusions of tests are that the bearing capacity of connections with sandblasted surface joining elements observes the norms while the bearing capacity of connections with painted – surface joining elements does not observes the norms.

  3. Hand grip strength and anthropometric characteristics in Italian female national basketball teams.

    Science.gov (United States)

    Pizzigalli, Luisa; Micheletti Cremasco, Margherita; LA Torre, Antonio; Rainoldi, Alberto; Benis, Roberto

    2017-05-01

    The aim of this study was to investigate the influence of hand and body dimensions on hand grip strength and to define a reference scale for talent identification in basketball players. Body and hand anthropometric data and the maximal handgrip strength of 109 female Italian basketball National players (Under14-Seniores) were measured. Handgrip strength and arm length trend increased, raising the statistical significant differences only for players from the age of 19 (U20, Seniores) with respect to sub-elite groups (U14, U15) (P<0.05). Handgrip strength showed low positive correlations with height and Body Mass Index but a positive relationships with arm length (r=0.5; P<0.001). Findings underline training and years of practice have effects on increasing handgrip strength. Data show that to select female basketball players by arm length means selecting by handgrip strength. Thus it is possible to suggest that in addition to height, arm length could also be considered a useful parameter in young female talent identification.

  4. Public perceptions of a rip current hazard education program: "Break the Grip of the Rip!"

    Science.gov (United States)

    Houser, Chris; Trimble, Sarah; Brander, Robert; Brewster, B. Chris; Dusek, Greg; Jones, Deborah; Kuhn, John

    2017-07-01

    Rip currents pose a major global beach hazard; estimates of annual rip-current-related deaths in the United States alone range from 35 to 100 per year. Despite increased social research into beach-goer experience, little is known about levels of rip current knowledge within the general population. This study describes the results of an online survey to determine the extent of rip current knowledge across the United States, with the aim of improving and enhancing existing beach safety education material. Results suggest that the US-based Break the Grip of the Rip!text">® campaign has been successful in educating the public about rip current safety directly or indirectly, with the majority of respondents able to provide an accurate description of how to escape a rip current. However, the success of the campaign is limited by discrepancies between personal observations at the beach and rip forecasts that are broadcasted for a large area and time. It was the infrequent beach user that identified the largest discrepancies between the forecast and their observations. Since infrequent beach users also do not seek out lifeguards or take the same precautions as frequent beach users, it is argued that they are also at greatest risk of being caught in a dangerous situation. Results of this study suggest a need for the national campaign to provide greater focus on locally specific and verified rip forecasts and signage in coordination with lifeguards, but not at the expense of the successful national awareness program.

  5. The predictive value of extensor grip test for the effectiveness of treatment for tennis elbow

    International Nuclear Information System (INIS)

    Zehtab, Mohammad J.; Mirghasemi, A.; Majlesara, A.; Siavashi, B.; Tajik, P.

    2008-01-01

    Objective was to compare the effectiveness of 5 different modalities and determine the usefulness of recently proposed extensor grip test (EGT) in predicting the response to treatment. In a randomized controlled clinical trial, 92 of 98 tennis elbow patients in Sina Hospital Tehran, Iran between 2006 and 2007 fulfilled the trial entry criteria. Among these patients 56 (60.9%) had positive EGT results, were randomly allocated to 5 treatment groups: brace, physiotherapy, brace plus physiotherapy, injection and injection plus physiotherapy. Patients with a positive EGT result had better response to treatments. Among them, injection plus physiotherapy was the most successful, then brace plus physiotherapy was the worst treatment modality. Response to treatment was comparable in all groups between EGT positive and negative patients except bracing, in which positive EGT was correlated with dramatic response to treatment. In all patients, injection plus physiotherapy and the brace plus physiotherapy is recommended, but in EGT negatives, bracing seems to be of no use. Injection alone is not recommended in either group. (author)

  6. Reliable and Accurate Release of Micro-Sized Objects with a Gripper that Uses the Capillary-Force Method

    Directory of Open Access Journals (Sweden)

    Suzana Uran

    2017-06-01

    Full Text Available There have been recent developments in grippers that are based on capillary force and condensed water droplets. These are used for manipulating micro-sized objects. Recently, one-finger grippers have been produced that are able to reliably grip using the capillary force. To release objects, either the van der Waals, gravitational or inertial-forces method is used. This article presents methods for reliably gripping and releasing micro-objects using the capillary force. The moisture from the surrounding air is condensed into a thin layer of water on the contact surfaces of the objects. From the thin layer of water, a water meniscus between the micro-sized object, the gripper and the releasing surface is created. Consequently, the water meniscus between the object and the releasing surface produces a high enough capillary force to release the micro-sized object from the tip of the one-finger gripper. In this case, either polystyrene, glass beads with diameters between 5–60 µm, or irregularly shaped dust particles of similar sizes were used. 3D structures made up of micro-sized objects could be constructed using this method. This method is reliable for releasing during assembly and also for gripping, when the objects are removed from the top of the 3D structure—the so-called “disassembling gripping” process. The accuracy of the release was lower than 0.5 µm.

  7. Bimanual force coordination in Parkinson's disease patients with bilateral subthalamic deep brain stimulation.

    Directory of Open Access Journals (Sweden)

    Stacey L Gorniak

    Full Text Available Studies of bimanual actions similar to activities of daily living (ADLs are currently lacking in evaluating fine motor control in Parkinson's disease patients implanted with bilateral subthalamic deep brain stimulators. We investigated basic time and force characteristics of a bimanual task that resembles performance of ADLs in a group of bilateral subthalamic deep brain stimulation (DBS patients.Patients were evaluated in three different DBS parameter conditions off stimulation, on clinically derived stimulation parameters, and on settings derived from a patient-specific computational model. Model-based parameters were computed as a means to minimize spread of current to non-motor regions of the subthalamic nucleus via Cicerone Deep Brain Stimulation software. Patients were evaluated off parkinsonian medications in each stimulation condition.The data indicate that DBS parameter state does not affect most aspects of fine motor control in ADL-like tasks; however, features such as increased grip force and grip symmetry varied with the stimulation state. In the absence of DBS parameters, patients exhibited significant grip force asymmetry. Overall UPDRS-III and UPDRS-III scores associated with hand function were lower while patients were experiencing clinically-derived or model-based parameters, as compared to the off-stimulation condition.While bilateral subthalamic DBS has been shown to alleviate gross motor dysfunction, our results indicate that DBS may not provide the same magnitude of benefit to fine motor coordination.

  8. Hand grips strength effect on motor function in human brain using fMRI: a pilot study

    International Nuclear Information System (INIS)

    Ismail, S S; Mohamad, M; Syazarina, S O; Nafisah, W Y

    2014-01-01

    Several methods of motor tasks for fMRI scanning have been evolving from simple to more complex tasks. Motor tasks on upper extremity were applied in order to excite the increscent of motor activation on contralesional and ipsilateral hemispheres in brain. The main objective of this study is to study the different conditions for motor tasks on upper extremity that affected the brain activation. Ten healthy right handed with normal vision (3 male and 7 female, age range=20-30 years, mean=24.6 years, SD=2.21) participated in this study. Prior to the scanning, participants were trained on hand grip tasks using rubber ball and pressure gauge tool outside the scanner. During fMRI session, a block design with 30-s task blocks and alternating 30-s rest periods was employed while participants viewed a computer screen via a back projection-mirror system and instructed to follow the instruction by gripping their hand with normal and strong grips using a rubber ball. Statistical Parametric mapping (SPM8) software was used to determine the brain activation. Both tasks activated the primary motor (M1), supplementary motor area (SMA), dorsal and ventral of premotor cortex area (PMA) in left hemisphere while in right hemisphere the area of primary motor (M1) somatosensory was activated. However, the comparison between both tasks revealed that the strong hand grip showed the higher activation at M1, PMA and SMA on left hemisphere and also the area of SMA on right hemisphere. Both conditions of motor tasks could provide insights the functional organization on human brain

  9. Hand grips strength effect on motor function in human brain using fMRI: a pilot study

    Science.gov (United States)

    Ismail, S. S.; Mohamad, M.; Syazarina, S. O.; Nafisah, W. Y.

    2014-11-01

    Several methods of motor tasks for fMRI scanning have been evolving from simple to more complex tasks. Motor tasks on upper extremity were applied in order to excite the increscent of motor activation on contralesional and ipsilateral hemispheres in brain. The main objective of this study is to study the different conditions for motor tasks on upper extremity that affected the brain activation. Ten healthy right handed with normal vision (3 male and 7 female, age range=20-30 years, mean=24.6 years, SD=2.21) participated in this study. Prior to the scanning, participants were trained on hand grip tasks using rubber ball and pressure gauge tool outside the scanner. During fMRI session, a block design with 30-s task blocks and alternating 30-s rest periods was employed while participants viewed a computer screen via a back projection-mirror system and instructed to follow the instruction by gripping their hand with normal and strong grips using a rubber ball. Statistical Parametric mapping (SPM8) software was used to determine the brain activation. Both tasks activated the primary motor (M1), supplementary motor area (SMA), dorsal and ventral of premotor cortex area (PMA) in left hemisphere while in right hemisphere the area of primary motor (M1) somatosensory was activated. However, the comparison between both tasks revealed that the strong hand grip showed the higher activation at M1, PMA and SMA on left hemisphere and also the area of SMA on right hemisphere. Both conditions of motor tasks could provide insights the functional organization on human brain.

  10. Cut-off Points for Muscle Mass - Not Grip Strength or Gait Speed - Determine Variations in Sarcopenia Prevalence.

    Science.gov (United States)

    Masanés, F; Rojano I Luque, X; Salvà, A; Serra-Rexach, J A; Artaza, I; Formiga, F; Cuesta, F; López Soto, A; Ruiz, D; Cruz-Jentoft, A J

    2017-01-01

    The European Working Group on Sarcopenia in Older People (EWGSOP) has proposed different methods and cut-off points for the three parameters that define sarcopenia: muscle mass, muscle strength and physical performance. Although this facilitates clinical practice, it limits comparability between studies and leads to wide differences in published prevalence rates. The aim of this study was to assess how changes in cut-off points for muscle mass, gait speed and grip strength affected sarcopenia prevalence according to EWGSOP criteria. Cross-sectional analysis of elderly individuals recruited from outpatient clinics (n=298) and nursing homes (n=276). We measured muscle mass, grip strength and gait speed and assessed how changes in cut-off points changed sarcopenia prevalence in both populations. An increase from 5.45 kg/m2 to 6.68 kg/m2 in the muscle mass index for female outpatients and nursing-home residents increased sarcopenia prevalence from 4% to 23% and from 9% to 47%, respectively; for men, for an increase from 7.25 kg/m2 to 8.87 kg/m2, the corresponding increases were from 1% to 22% and from 6% to 41%, respectively. Changes in gait speed and grip strength had a limited impact on sarcopenia prevalence. The cut-off points used for muscle mass affect the reported prevalence rates for sarcopenia and, in turn, affect comparability between studies. The main factors influencing the magnitude of the change are muscle mass index distribution in the population and the absolute value of the cut-off points: the same difference between two references (e.g., 7.5 kg/m2 to 7.75 kg/m2 or 7.75 kg/m2 to 8 kg/m2) may produce different changes in prevalence. Changes in cut-off points for gait speed and grip strength had a limited impact on sarcopenia prevalence and on study comparability.

  11. The Association Between Sleep Duration and Hand Grip Strength in Community-Dwelling Older Adults: The Yilan Study, Taiwan.

    Science.gov (United States)

    Chen, Hsi-Chung; Hsu, Nai-Wei; Chou, Pesus

    2017-04-01

    Different pathomechanisms may underlie the age-related decline in muscle mass and muscle power in older adults. This study aimed to examine the independent relationship between sleep duration and muscle power. Older adults, aged 65 years and older, were randomly selected to participate in a community-based survey in Yilan city, Taiwan. Data on self-reported sleep duration, sociodemographic information, lifestyle, chronic medical and mental health conditions, sleep-related parameters, and anthropometric measurements were collected. Participants who slept ≤4 hr, 5 hr, 6-7 hr, 8 hr, and ≥9 hr were defined as shortest, short, mid-range, long, and longest sleepers, respectively. Muscle power was estimated using hand grip strength. A total of 1081 individuals participated. Their average age was 76.3 ± 6.1 years, and 59.4% were female. After controlling for covariates, including muscle mass of the upper extremities, both long (estimated mean [95% confidence interval, CI]: 19.2 [18.2-20.2], p = .03) and longest sleepers (estimated mean [95% CI]: 17.8 [16.4-19.2], p = .001) had weaker hand grip strength than mid-range sleepers (estimated mean [95% CI]: 20.9 [20.3-21.4]). When stratified by sex, the association between longest sleep duration and weaker hand grip strength was noted among men only. Older adults with long sleep duration had weaker hand grip strength irrespective of muscle mass. This finding suggests that decreased muscle power may mediate or confound the relationship between long sleep duration and adverse health outcomes. © Sleep Research Society 2017. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

  12. Test-Retest Reliability of Measurements of Hand-Grip Strength Obtained by Dynamometry from Older Adults: A Systematic Review of Research in the PubMed Database.

    Science.gov (United States)

    Bohannon, R W

    2017-01-01

    A systematic review was performed to summarize literature describing the test-retest reliability of grip strength measures obtained from older adults. Relevant literature was identified via a PubMed search. Seventeen articles were deemed appropriate based on inclusion and exclusion criteria. The relative test-retest reliability of grip strength measures obtained by dynamometry was good to excellent (intra-class correlation coefficients > 0.80) in all but 3 studies, which involved older adults with severe dementia. Absolute reliability, as indicated by summary statistics such as the minimum detectable change (95%), was more variable. As a percentage, that change ranged from 14.5% to 98.5%. Consequently, clinicians can be confident in the relative reliability of grip strength measures obtained from at risk older adults. However, relatively large percentage changes in grip strength may be necessary to conclude with confidence that a real change has occurred over time in some populations.

  13. Installation of dynamic travel time signs and efforts to obtain and test a graphical route information panel (GRIP) sign in Austin.

    Science.gov (United States)

    2016-08-01

    Graphic Route Information Panel (GRIP) signs use a combination of text, colors, and representative maps of : the roadway system to convey real-time roadway congestion location and severity information. The intent of : this project was to facilitate t...

  14. Sex Differences in the Level and Rate of Change of Physical Function and Grip Strength in the Danish 1905-Cohort Study

    DEFF Research Database (Denmark)

    Oksuzyan, Anna; Maier, Heiner; McGue, Matt

    2010-01-01

    OBJECTIVE: The study was conducted to examine sex differences in the initial level and rate of change in physical function and grip strength. METHOD: The baseline survey included 2,262 Danes born in 1905 and alive in 1998 and followed-up in 2000, 2003, and 2005. Hence, the authors fully used...... the power of having a cohort with multiple assessments in late life and virtually complete follow-up of lifespan (through December 2008). Latent growth curve modeling was used. RESULTS: Men had higher initial levels and rates of decline in strength score and grip strength. Lifespan was positively correlated...... with intercepts and slopes. DISCUSSION: The Danish data suggested that the longest-living individuals have higher initial levels of strength score and grip strength and smaller rate of change. The data further suggested that the initial level of strength score and grip strength was more predictive of mortality...

  15. Effects of exercise training experience on hand grip strength, body composition and postural stability in fitness pole dancers.

    Science.gov (United States)

    Nawrocka, Agnieszka; Mynarski, Arkadiusz; Powerska, Aneta; Rozpara, Michał; Garbaciak, Wiesław

    2017-09-01

    Although the growing popularity of pole dance as a leisure-time activity of people of all ages, the problem of physical effects of exercise on the pole is not considered in the scientific literature. The aim of this study was to evaluate and compare the hand grip strength, body composition and postural stability of fitness pole dancers with different training experience. The inclusion criteria for this study were met by 52 female pole dancers. The research program included assessment of body composition (using BC-418 Segmental Body Composition Analyzer, Tanita, Tokyo, Japan), hand grip strength by hydraulic dynamometer JAMAR, and postural stability using ALFA stabilometric platform. Significant differences depending on the pole dance advancement level were found in postural stability and hand-grip strength. The average values of the surface area and the length sway indicated by feet center of pressure were significantly decreasing with the increasing group experience (PStrength level was increasing with the consecutive advancement level (right hand χ2=9.595, P=0.008, left hand χ2=8.936, P=0.011). Regular practice of pole dance fitness can contribute to a significant increase of strength and improvement of the postural stability, which is important for the entire musculoskeletal system. However, further studies on the beneficial and negative (e.g. injuries) impact of exercises on the pole on the musculoskeletal system are required, including larger group of respondents, their diverse age and, above all, longitudinal studies.

  16. Wheelchair Mobility Performance enhancement by Changing Wheelchair Properties; What is the Effect of Grip, Seat Height and Mass?

    Science.gov (United States)

    van der Slikke, Rienk M A; de Witte, Annemarie M H; Berger, Monique A M; Bregman, Daan J J; Veeger, Dirk Jan H E J

    2018-02-12

    The purpose of this study was to provide insight in the effect of wheelchair settings on wheelchair mobility performance. Twenty elite wheelchair basketball athletes of low (n=10) and high classification (n=10), were tested in a wheelchair basketball directed field test. Athletes performed the test in their own wheelchair, which was modified for five additional conditions regarding seat height (high - low), mass (central - distributed) and grip. The previously developed, inertial sensor based wheelchair mobility performance monitor 1 was used to extract wheelchair kinematics in all conditions. Adding mass showed most effect on wheelchair mobility performance, with a reduced average acceleration across all activities. Once distributed, additional mass also reduced maximal rotational speed and rotational acceleration. Elevating seat height had effect on several performance aspects in sprinting and turning, whereas lowering seat height influenced performance minimally. Increased rim grip did not alter performance. No differences in response were evident between low and high classified athletes. The wheelchair mobility performance monitor showed sensitive to detect performance differences due to the small changes in wheelchair configuration made. Distributed additional mass had the most effect on wheelchair mobility performance, whereas additional grip had the least effect of conditions tested. Performance effects appear similar for both low and high classified athletes. Athletes, coaches and wheelchair experts are provided with insight in the performance effect of key wheelchair settings, and they are offered a proven sensitive method to apply in sports practice, in their search for the best wheelchair-athlete combination.

  17. The association of early life supplemental nutrition with lean body mass and grip strength in adulthood: evidence from APCAPS.

    Science.gov (United States)

    Kulkarni, Bharati; Kuper, Hannah; Radhakrishna, K V; Hills, Andrew P; Byrne, Nuala M; Taylor, Amy; Sullivan, Ruth; Bowen, Liza; Wells, Jonathan C; Ben-Shlomo, Yoav; Davey Smith, George; Ebrahim, Shah; Kinra, Sanjay

    2014-03-15

    In the present study, we examined the associations of early nutrition with adult lean body mass (LBM) and muscle strength in a birth cohort that was established to assess the long-term impact of a nutrition program. Participants (n = 1,446, 32% female) were born near Hyderabad, India, in 29 villages from 1987 to 1990, during which time only intervention villages (n = 15) had a government program that offered balanced protein-calorie supplementation to pregnant women and children. Participants' LBM and appendicular skeletal muscle mass were measured using dual energy x-ray absorptiometry; grip strength and information on lifestyle indicators, including diet and physical activity level, were also obtained. Ages (mean = 20.3 years) and body mass indexes (weight (kg)/height (m)(2); mean = 19.5) of participants in 2 groups were similar. Current dietary energy intake was higher in the intervention group. Unadjusted LBM and grip strength were similar in 2 groups. After adjustment for potential confounders, the intervention group had lower LBM (β = -0.75; P = 0.03), appendicular skeletal muscle mass, and grip strength than did controls, but these differences were small in magnitude (supplementation on adult LBM and muscle strength.

  18. Anticipating different grips reduces bimanual end-state comfort: A tradeoff between goal-related and means-related planning processes.

    Directory of Open Access Journals (Sweden)

    Christian Seegelke

    Full Text Available The present study explored the sensitivity towards bimanual end-state comfort in a task that required anticipating different final grips. Participants simultaneously reached and grasped two objects with either a whole-hand grip (WHG or a precision grip (PG, and placed them at two target locations by transporting them either over or under an obstacle. The transport path was varied such that it could be either congruent (i.e., both objects over or under or incongruent (i.e., one object over and the other object under. In the congruent conditions, participants satisfied bimanual end-state comfort (and identical initial grips on the majority of trials. That is, participants adopted a PG for either hand when the objects were transported over the obstacle and a WHG for either hand when the objects were transported under the obstacle. In contrast, in the incongruent conditions, bimanual end-state comfort was significantly reduced, indicating the presence of intermanual inference. The results indicate that goal-related planning constraints (i.e., bimanual end-state comfort do not strictly take precedence over means-related constraints (i.e., identical initial grips if this requires anticipating different final grips. Thus, bimanual end-state comfort per se does not provide a predominant constraint in action selection, by which sensorimotor interference can be reduced. In line with the proposal that bimanual grip planning relies on a flexible constraint hierarchy, a simple formal model that considers bimanual grip posture planning as a tradeoff between goal-related and means-related planning processes can explain our results reasonably well.

  19. The Activities of the Muscles around the Ankle Joint during Foot-gripping are Affected by the Angle of the Ankle

    OpenAIRE

    Soma, Masayuki; Murata, Shin; Kai, Yoshihiro; Nakae, Hideyuki; Satou, Yosuke

    2014-01-01

    [Purpose] The purpose of this study was to determine the activities of the muscles around the ankle joint during foot gripping. [Subjects] The subjects of this study were 17 healthy females. [Methods] We measured the maximum voluntary contraction (MVC) activities of the soleus muscle, the medial head of the gastrocnemius muscle, and the tibialis anterior muscle, and calculated %IEMG during foot gripping in 3 different ankle joint positions: 10° of plantar flexion, 0°, and 10° of dorsiflexion....

  20. The Vacuum-Compacted Regolith Gripping Mechanism and Unmanned Flights via Quad-Rotors

    Science.gov (United States)

    Scott, Rollin L.

    2014-01-01

    During the course of the Kennedy Space Center Summer Internship, two main experiments were performed: The Vacuum-Compacted Regolith Gripping Mechanism and Unmanned Flights via Quad-copters. The objectives of the Vacuum-Compacted Regolith Gripping Mechanism, often abbreviated as the Granular Gripper, are to exhibit Space Technology, such as a soft robotic hand, lift different apparatuses used to excavate regolith, and conserve energy while executing its intended task. The project is being conducted to test how much weight the Granular Gripper can hold. With the use of an Animatronic Robotic Hand, Arduino Uno, and other components, the system was calibrated before actually conducting the intended weight test. The maximum weight each finger could hold with the servos running, in the order of pinky, ring, middle, and index fingers, are as follows: 1.340N, 1.456 N, 0.9579 N, and 1.358 N. Using the small vacuum pump system, the maximum weight each finger could hold, in the same order, was: 4.076 N, 6.159 N, 5.454 N, and 4.052 N. The maximum torques on each of the fingers when the servos were running, in the same respective order, was: 0.0777 Nm, 0.0533 Nm, 0.0648 Nm, and 0.0532 Nm. The maximum torques on the individual fingers, when the small vacuum pump was in effect, in the same order as above, was: 0.2318 Nm, 0.3032 Nm, 0.2741 Nm, and 0.1618 Nm. In testing all the fingers with the servos running, the total weight was 5.112 N and the maximum torque on the all the fingers was 0.2515 Nm. However, when the small vacuum pump system was used, the total weight was 19.741 N and the maximum torque on the all the fingers was 0.9713 Nm. The conclusion that was drawn stated that using the small vacuum pump system proved nearly 4 times more effective when testing how much weigh the hand could hold. The resistance provided by the compacted sand in the glove allowed more weight to be held by the hand and glove. Also, when the servos turned off and the hand still retaining its

  1. Effects of gripping volume in the mechanical strengths of orthodontic mini-implant

    Directory of Open Access Journals (Sweden)

    Yu-Chuan Tseng

    2017-11-01

    Full Text Available The objective of study was to investigate the correlation between the mechanical strengths [insertion torque (IT; resonance frequency (RF; and horizontal pullout strength (HPS] and gripping volume (GV of mini-implants. Thirty mini-implants of three types (Type A: 2 mm × 10 mm, cylindrical, titanium alloy; Type B: 2 mm × 10 mm, tapered, stainless steel; and Type C: 2 mm × 11 mm, cylindrical, titanium alloy were inserted 7 mm into artificial bones. One-way analysis of variance and Spearman's test were applied to assess intergroup comparisons and intragroup correlations. The null hypothesis was that no statistically significant correlations exist between the GV and mechanical strengths (IT, RF, and HPS. In the IT test, Type C (14.2 Ncm had significantly (p=0.016 greater values than did Type A (12.4 Ncm. In the RF analysis, no significant difference was observed among the three types of mini-implants. In the HPS test, Type C (388.9 Ncm was significantly larger than both Type B (294.5 Ncm and Type A (286 Ncm. In the GV measurement, Type C (14.4 mm3 was significantly larger than Type B (11.4 mm3 and Type A (9.2 mm3. Type A and Type B exhibited no significant correlations among the tests. Therefore, the null hypothesis was accepted. Although no significant correlation was noted between the GV and mechanical strengths (IT, RF, and HPS, we observed a trend that the mechanical strengths (IT, RF, and HPS of the mini-implants corresponded to the order and values of GV (Type C > Type B > Type A.

  2. Hand Grip Strength in Low, Medium, and High Body Mass Index Males and Females

    Directory of Open Access Journals (Sweden)

    Liao

    2016-01-01

    Full Text Available Background Hand grip strength (HGS is a predictor of upper extremity function and changes in muscle strength, physical movement and ability to undertake activities of daily living. Body mass index (BMI is a critical indicator of physical health; however, the relationship between HGS and BMI has not yet been thoroughly examined. Objectives The current study aims to compare HGS in low, medium, and high BMI males and females in both hands, and also investigates the correlation between HGS and anthropometric characteristics among the three BMI groups. Patients and Methods The study included 200 participants who were divided into three groups based on their BMI (60 low, 58 medium, and 82 high. HGS was assessed using a hand-held Jamar dynamometer. BMI was assessed by an electric body-weight height analysis machine. Data was analyzed using descriptive and inferential statistics at P 0.05. Weight and height strongly correlated with HGS for hands (correlation (r ranged from 0.000 - 0.775. Regression analysis showed that when using sex and BMI as independent variables for predicting the dependent variable HGS, the coefficient of the determinant R2 was 0.753 (P < 0.001. Conclusions The current study revealed that a significant difference existed in HGS among the low, medium, and high BMI groups. A positive correlation existed between HGS and weight and height, while sex was the most significant factor affecting HGS. These findings can serve as a reference to assess HGS prediction, whereby the sex effect should be considered.

  3. Self-organization, free energy minimization, and optimal grip on a field of affordances.

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    Bruineberg, Jelle; Rietveld, Erik

    2014-01-01

    In this paper, we set out to develop a theoretical and conceptual framework for the new field of Radical Embodied Cognitive Neuroscience. This framework should be able to integrate insights from several relevant disciplines: theory on embodied cognition, ecological psychology, phenomenology, dynamical systems theory, and neurodynamics. We suggest that the main task of Radical Embodied Cognitive Neuroscience is to investigate the phenomenon of skilled intentionality from the perspective of the self-organization of the brain-body-environment system, while doing justice to the phenomenology of skilled action. In previous work, we have characterized skilled intentionality as the organism's tendency toward an optimal grip on multiple relevant affordances simultaneously. Affordances are possibilities for action provided by the environment. In the first part of this paper, we introduce the notion of skilled intentionality and the phenomenon of responsiveness to a field of relevant affordances. Second, we use Friston's work on neurodynamics, but embed a very minimal version of his Free Energy Principle in the ecological niche of the animal. Thus amended, this principle is helpful for understanding the embeddedness of neurodynamics within the dynamics of the system "brain-body-landscape of affordances." Next, we show how we can use this adjusted principle to understand the neurodynamics of selective openness to the environment: interacting action-readiness patterns at multiple timescales contribute to the organism's selective openness to relevant affordances. In the final part of the paper, we emphasize the important role of metastable dynamics in both the brain and the brain-body-environment system for adequate affordance-responsiveness. We exemplify our integrative approach by presenting research on the impact of Deep Brain Stimulation on affordance responsiveness of OCD patients.

  4. An investigation of the tri-bar gripping system on isometric muscular endurance.

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    Drury, Daniel G; Faggiono, Heath; Stuempfle, Kristin J

    2004-11-01

    Recently, a new product called the Tri-Bar has been introduced as an alternative to the standard round weightlifting bar. The Tri-Bar has the same weight, length, and circumference as a standard weightlifting bar and differs only in that the shape of the bar is formed like a triangle with rounded edges. Theoretically, the shape of the bar will enhance gripping comfort and increase muscular endurance. We studied 32 moderately trained males who were free from upper-body injury or limitation. Each participant completed 4 visits to the lab as part of 2 separate investigations. The first investigation was a comparison of straight-arm hang times while grasping a standard Olympic bar or a Tri-Bar attached to the top of a power rack. The second investigation involved grasping a standard revolving cable handle or a Tri-Bar revolving handle attached to a weight equal to half the subject's body weight. In both investigations, time was used as a measure of isometric muscular endurance. Differences were determined using a dependent t-test, and a level of significance was set at p < 0.05. Mean hang times were significantly longer when the men hung from the Tri-Bar (107.6 seconds) versus the standard bar (95.4 seconds) (p = 0.015). Conversely, in the investigation using the revolving handles, the round bar produced longer grasping times (71.5 seconds) than the Tri-Bar (62.6 seconds) (p = 0.000). The results of this investigation indicate that a fixed and stable Tri-Bar may help to increase hang time, but a Tri-Bar free to rotate within the grasp may decrease grasping time in comparison to a standard round handle. With regard to exercises that require isometric grasping, the Tri-Bar may be an effective alternative to the standard bar for increasing isometric grasping endurance.

  5. Birth weight, intrauterine growth restriction and nutritional status in childhood in relation to grip strength in adults: from the 1982 Pelotas (Brazil) birth cohort.

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    Bielemann, Renata Moraes; Gigante, Denise Petrucci; Horta, Bernardo Lessa

    2016-02-01

    The aim of this study was to evaluate the association among birth weight, intrauterine growth, and nutritional status in childhood with grip strength in young adults from the 1982 Pelotas (Brazil) birth cohort. In 1982, the hospital live births of Pelotas were followed. In 2012, grip strength was evaluated using a hand dynamometer and the best of the six measurements was used. Birth weight was analyzed as z-score for gestational age according to Williams (1982) curve. Weight-for-age, weight-for-length/height, and length/height-for-age at 2 and 4 y were analyzed in z-scores according to 2006 World Health Organization Child Growth Standards. Lean mass at 30 y was included as possible mediator using the g-computation formula. In 2012, 3701 (68.1%) individuals were interviewed and 3470 were included in the present analyses. An increase of 1 z-score in birth weight was associated with an increase of 1.5 kg in grip strength in males (95% confidence interval, 1.1-1.9). Positive effect of birth weight on grip strength was found in females. Grip strength was greater in individuals who were born with appropriate size for gestational age and positively associated with weight- and length/height-for-age z-score at 2 and 4 y of age. A positive association between birth weight and grip strength was only partially mediated by adult lean mass (50% and 33% of total effect in males and females), whereas direct effect of weight at 2 y was found only in males. It is suggested that good nutrition in prenatal and early postnatal life has a positive influence on adult muscle strength. The results from birth weight were suggestive of fetal programming on grip strength measurement. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  6. Grip strength in a cohort of older medical inpatients in Malaysia: a pilot study to describe the range, determinants and association with length of hospital stay.

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    Keevil, Victoria; Mazzuin Razali, Rizah; Chin, Ai-Vyrn; Jameson, Karen; Aihie Sayer, Avan; Roberts, Helen

    2013-01-01

    Grip strength is a marker of sarcopenia, the age-related decline in muscle mass and function, and has been little researched in Asian populations. We aimed to describe the feasibility and acceptability of measuring grip strength in hospitalized, older people in Malaysia and to explore its range, determinants and association with length of stay. Patients admitted acutely to the geriatrics ward of a teaching hospital were consecutively recruited. Inability to consent or use the dynamometer led to exclusion. Maximum grip strength, anthropometric data, length of hospital stay, discharge destination, 3-point Barthel score, mini-mental state examination, falls history and number of co-morbidities and medications on admission were recorded. 80/153 (52%) eligible patients were recruited (52 women; age range 64-100 years). 9/153 (6%) refused to participate and 64/153 (42%) were excluded (34 too unwell, 24 unable to consent, 4 unable to use the dynamometer, 2 other reasons). 76/80 patients (95%) reported that they would undergo grip strength measurement again. Determinants were similar to those of Caucasian populations but grip strength values were lower. After adjustment for sex, age and height, stronger grip strength was associated with shorter length of stay [hazard ratio 1.05 (95% CI 1.00, 1.09; P=0.03)]. This is the first report of grip strength measurement in hospitalized older people in Malaysia. It was feasible, acceptable to participants and associated with length of stay. Further research is warranted to elucidate the normative range in different ethnic groups and explore its potential use in clinical practice in Malaysia. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  7. Cluster forcing

    DEFF Research Database (Denmark)

    Christensen, Thomas Budde

    , Portugal and New Zealand have adopted the concept. Public sector interventions that aim to support cluster development in industries most often focus upon economic policy goals such as enhanced employment and improved productivity, but rarely emphasise broader societal policy goals relating to e.......g. sustainability or quality of life. The purpose of this paper is to explore how and to what extent public sector interventions that aim at forcing cluster development in industries can support sustainable development as defined in the Brundtland tradition and more recently elaborated in such concepts as eco...... in 2000 by the Welsh Automotive Task Force under the Welsh Assembly Government. The Accelerate programme takes basically different two directions: The first one, which was the first to be launched, is concerned with the upgrading of existing supply chains in the automotive industry in Wales. The programme...

  8. Testing the efficacy of existing force-endurance models to account for the prevalence of obesity in the workforce.

    Science.gov (United States)

    Pajoutan, Mojdeh; Cavuoto, Lora A; Mehta, Ranjana K

    2017-10-01

    This study evaluates whether the existing force-endurance relationship models are predictive of endurance time for overweight and obese individuals, and if not, provide revised models that can be applied for ergonomics practice. Data was collected from 141 participants (49 normal weight, 50 overweight, 42 obese) who each performed isometric endurance tasks of hand grip, shoulder flexion, and trunk extension at four levels of relative workload. Subject-specific fatigue rates and a general model of the force-endurance relationship were determined and compared to two fatigue models from the literature. There was a lack of fit between previous models and the current data for the grip (ICC = 0.8), with a shift toward lower endurance times for the new data. Application of the revised models can facilitate improved workplace design and job evaluation to accommodate the capacities of the current workforce.

  9. alpha2 adrenoceptors are involved in the regulation of the gripping-induced immobility episodes in taiep rats.

    Science.gov (United States)

    Eguibar, José R; Cortés, Ma Del Carmen; Valencia, Jaime; Arias-Montaño, José A

    2006-10-01

    In 1989 Holmgren et al. (Holmgren et al. 1989 Lab Anim Sci 39:226-228) described a new mutant rat that developed a progressive motor disturbance during its lifespan. The syndrome is characterized by a tremor in the hind limbs followed by ataxia, episodes of tonic immobility, epilepsy, and paralysis. The acronym of these symptoms (taiep) became the name of this autosomic, recessive mutant rat. The taiep rats are neurological mutant animals with a hypomyelination, followed by a progressive demyelination process. At 7-8 months of age, taiep rats develop immobility episodes (IEs) characterized by a cortical desynchronization, associated with the theta rhythm in the hippocampus and changes of the nucal electromyogram (EMG), whose pattern is like rapid-eye-movement (REM) sleep. These rats also show an altered sleep pattern with an equal REM sleep distribution. This study analyzed therole of alpha(2) adrenoceptors in the expression of gripping-induced IEs in 8-month-old male taiep rats. The alpha(2) adrenoceptor agonists clonidine and xylacine increased the frequency of gripping-induced IEs whereas the alpha(2) antagonists yohimbine and idazoxandecreased or prevented such episodes. These findings correlate with the pharmacological observations in narcoleptic dogs and humans in which alpha(2) adrenergic mechanisms are involved in the modulation of cataplexy. Unexpectedly, the repetitive administration of clonidine resulted in jumping behavior, indicative of phasic activation of extensor musculature. Taken together, our results show that alpha(2) adrenoceptors are involved in the modulation in gripping-induced IEs and after the administration of several doses of clonidine produced phasic motor activation.

  10. Hecate/Grip2a acts to reorganize the cytoskeleton in the symmetry-breaking event of embryonic axis induction.

    Science.gov (United States)

    Ge, Xiaoyan; Grotjahn, Danielle; Welch, Elaine; Lyman-Gingerich, Jamie; Holguin, Christiana; Dimitrova, Eva; Abrams, Elliot W; Gupta, Tripti; Marlow, Florence L; Yabe, Taijiro; Adler, Anna; Mullins, Mary C; Pelegri, Francisco

    2014-06-01

    Maternal homozygosity for three independent mutant hecate alleles results in embryos with reduced expression of dorsal organizer genes and defects in the formation of dorsoanterior structures. A positional cloning approach identified all hecate mutations as stop codons affecting the same gene, revealing that hecate encodes the Glutamate receptor interacting protein 2a (Grip2a), a protein containing multiple PDZ domains known to interact with membrane-associated factors including components of the Wnt signaling pathway. We find that grip2a mRNA is localized to the vegetal pole of the oocyte and early embryo, and that during egg activation this mRNA shifts to an off-center vegetal position corresponding to the previously proposed teleost cortical rotation. hecate mutants show defects in the alignment and bundling of microtubules at the vegetal cortex, which result in defects in the asymmetric movement of wnt8a mRNA as well as anchoring of the kinesin-associated cargo adaptor Syntabulin. We also find that, although short-range shifts in vegetal signals are affected in hecate mutant embryos, these mutants exhibit normal long-range, animally directed translocation of cortically injected dorsal beads that occurs in lateral regions of the yolk cortex. Furthermore, we show that such animally-directed movement along the lateral cortex is not restricted to a single arc corresponding to the prospective dorsal region, but occur in multiple meridional arcs even in opposite regions of the embryo. Together, our results reveal a role for Grip2a function in the reorganization and bundling of microtubules at the vegetal cortex to mediate a symmetry-breaking short-range shift corresponding to the teleost cortical rotation. The slight asymmetry achieved by this directed process is subsequently amplified by a general cortical animally-directed transport mechanism that is neither dependent on hecate function nor restricted to the prospective dorsal axis.

  11. Hand grip strength and chronic obstructive pulmonary disease in Korea: an analysis in KNHANES VI

    Directory of Open Access Journals (Sweden)

    Lee SH

    2017-08-01

    Full Text Available Su Hwan Lee, Soo Jung Kim, Yeji Han, Yon Ju Ryu, Jin Hwa Lee, Jung Hyun Chang Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Ewha Medical Research Institute, Ewha Womans University School of Medicine, Seoul, Korea Background: Muscle mass is known to be associated with mortality in elderly adults. Because hand grip strength (HGS is known as a simple assessment tool for muscular strength, many researchers have studied the association between HGS and disease. However, empirical evidence for the relationship between chronic obstructive pulmonary disease (COPD and HGS is still controversial. The aim of this study was to evaluate the association between COPD and HGS, using Korean population data. Methods: This was a population-based cross-sectional study. Data were obtained from the sixth Korean National Health and Nutrition Examination Survey, which was conducted from 2013 to 2015. To reduce the effects of HGS-related factors and potential confounding factors, propensity score matching was used to match subjects with and without COPD. Results: Among 14,930 subjects, 832 were enrolled in each group (non-COPD and COPD after propensity score matching. COPD subjects did not have lower HGS than non-COPD subjects (non-COPD vs COPD, male, 38.0±7.0 vs 38.9±7.0 kg, P=0.044, female, 23.8±4.6 vs 24.2±4.9 kg, P=0.342. Lung function was classified by Global Initiative for Chronic Obstructive Lung Disease stages and was not significantly associated with HGS. For male COPD subjects, there was a significant correlation between HGS and the EuroQol Five-Dimension Questionnaire (EQ5D utility score index, which is an indicator of quality of life that adjusts for age and body mass index (r=0.201, P<0.001. The correlation was absent for female subjects (r=0.098, P=0.170. Conclusion: COPD subjects did not have lower HGS than non-COPD subjects. HGS did not associate with lung function. However, the HGS of male COPD subjects was

  12. Effectiveness of Kinesio Taping for Hand on Grip Strength and Upper Limb Function in Subjects with Cervical Radiculopathy: A Randomized Controlled Trial

    Directory of Open Access Journals (Sweden)

    Shruti Prabhu

    2017-08-01

    Full Text Available Cervical radiculopathy is common condition seen today. It is found to associate with upper limb dysfunction which in turn hinders daily activity due to muscular weakness. Grip strength is found to be reduced in cervical radiculopathy and is taken to be a good measure of upper limb function. Treatment of cervical radiculopathy is mainly concentrated over neck region and very less has been done to improve upper limb function. Kinesio taping is found to improve muscle activity and can be used to improve grip strength and function in cervical radiculopathy. Method: 32 subjects with unilateral cervical radiculopathy were randomly divided into 2 groups, experimental and conventional group (n=16. The conventional group was given intermittent cervical traction, hot moist pack, TENS and exercises and experimental group was given conventional treatment along with kinesio taping to extensor aspect of forearm. Preand post-values for grip and pinch strength and NDI and DASH were assessed and analysed. Result: There was marked improvement seen both groups, but there was significant improvement in grip and pinch strength seen in experimental group while there was improvement seen functional outcomes namely NDI and DASH. This suggests that kinesio taping does not play a role in improving grip strength but can improve upper limb function.

  13. [Gait speed, grip strength and self-rated health among the elderly: data from the FIBRA Campinas network, São Paulo, Brazil].

    Science.gov (United States)

    Bez, Joelita Pessoa de Oliveira; Neri, Anita Liberalesso

    2014-08-01

    The article seeks to investigate patterns of performance and relationships between grip strength, gait speed and self-rated health, and investigate the relationships between them, considering the variables of gender, age and family income. This was conducted in a probabilistic sample of community-dwelling elderly aged 65 and over, members of a population study on frailty. A total of 689 elderly people without cognitive deficit suggestive of dementia underwent tests of gait speed and grip strength. Comparisons between groups were based on low, medium and high speed and strength. Self-related health was assessed using a 5-point scale. The males and the younger elderly individuals scored significantly higher on grip strength and gait speed than the female and oldest did; the richest scored higher than the poorest on grip strength and gait speed; females and men aged over 80 had weaker grip strength and lower gait speed; slow gait speed and low income arose as risk factors for a worse health evaluation. Lower muscular strength affects the self-rated assessment of health because it results in a reduction in functional capacity, especially in the presence of poverty and a lack of compensatory factors.

  14. Impact of mild versus moderate intensity aerobic walking exercise training on markers of bone metabolism and hand grip strength in moderate hemophilic A patients.

    Science.gov (United States)

    Al-Sharif, Fadwa Al-Ghalib; Al-Jiffri, Osama Hussien; El-Kader, Shehab Mahmoud Abd; Ashmawy, Eman Mohamed

    2014-03-01

    Patients with hemophilia A have low bone density than healthy controls. It is now widely recognized that physical activity and sports are beneficial for patients with hemophilia. To compare the effects of mild and moderate intensity treadmill walking exercises on markers of bone metabolism and hand grip strength in male patients with moderate hemophilia A. Fifty male patients with moderate hemophilia, and age range from 25 to 45 years. The subjects were randomly assigned into 2 equal groups; the first group (A) received moderate intensity aerobic exercise training. The second group (B) received mild intensity aerobic exercise training. There was a 32.1% and 24.8% increase in mean values of serum calcium and hand grip strength respectively and 22.7 % reduction in mean values of parathyroid hormone in moderate exercise training group (A). While there was a 15.1 % and 15 % increase in mean values of Serum Calcium and Hand grip strength respectively and 10.3 % reduction in mean values of parathyroid hormone in mild exercise training group(B). The mean values of serum calcium and hand grip strength were significantly increased, while the mean values of parathyroid hormone were significantly decreased in both groups . There were significant differences between mean levels of the investigated parameters in group (A) and group (B) after treatment. Moderate intensity aerobic exercise training on treadmill is appropriate to improve markers of bone metabolism and hand grip strength in male patients with hemophilia A.

  15. An investigation into normative values for fine hand dexterity and its relation with pinch and grip strength among healthy young Indian adults

    Directory of Open Access Journals (Sweden)

    Paul Anila

    2016-06-01

    Full Text Available An investigation into normative values for fine hand dexterity and its relation with pinch and grip strength among healthy young Indian adults. Evaluation of hand function is a crucial component to assess prognosis in hand pathologies. Examinations of dexterity provide unique way of evaluating neuro-motor function of entire hand. There is scarcity of literature on reference values for fine hand dexterity among healthy young adults. To explore normative values for fine hand dexterity and its relation with pinch and grip strength. The 9-Hole Pegboard Test was administered for evaluation of fine hand dexterity among healthy young adults (n= 256 of age group 18 to 35 with the mean age of 20.53 (±2.02. The task was demonstrated and both hands were assessed. Grip and pinch strengths were measured in both hands in a consistent manner. A dynamometer was used for grip strength and a pinch meter was used to measure key (lateral and tripod pinch and tip to tip pinch strengths. Normative value for fine hand dexterity of dominant hand among males (n= 125 is 19 (± 2.18 and among females (n= 126 is 19.5 (± 2.59 and there was no significant correlation between fine hand dexterity with grip and pinch strength. Normative values generated in this study can be used for clinical reference in the evaluation of hand function to that of normal subjects of the same age and gender.

  16. Manipulating Microrobots Using Balanced Magnetic and Buoyancy Forces

    Directory of Open Access Journals (Sweden)

    Lin Feng

    2018-01-01

    Full Text Available We present a novel method for the three-dimensional (3D control of microrobots within a microfluidic chip. The microrobot body contains a hollow space, producing buoyancy that allows it to float in a microfluidic environment. The robot moves in the z direction by balancing magnetic and buoyancy forces. In coordination with the motion of stages in the xy plane, we achieved 3D microrobot control. A microgripper designed to grasp micron-scale objects was attached to the front of the robot, allowing it to hold and deliver micro-objects in three dimensions. The microrobot had four degrees of freedom and generated micronewton-order forces. We demonstrate the microrobot’s utility in an experiment in which it grips a 200 μm particle and delivers it in a 3D space.

  17. Evaluation of finger A3 pulley rupture in the crimp grip position - a magnetic resonance imaging cadaver study

    Energy Technology Data Exchange (ETDEWEB)

    Bayer, Thomas; Uder, Michael; Janka, Rolf [University of Erlangen-Nuremberg, Department of Radiology, Erlangen (Germany); Adler, Werner [University of Erlangen-Nuremberg, Department of Biometry and Epidemiology, Erlangen (Germany); Schweizer, Andreas [Balgrist, University of Zurich, Department of Orthopaedics, Zurich (Switzerland); Schoeffl, Isabelle [Klinikum Bamberg, Department of Pediatrics, Bamberg (Germany)

    2015-09-15

    The correct diagnosis of an A3 pulley rupture is challenging for musculoskeletal radiologists. An A3 pulley rupture should in theory influence the shape of the proximal interphalangeal joint volar plate (VP) and the amount of bowstringing at level of the VP during finger flexion. The purpose of this study was to perform MRI with metric analysis of the VP configuration and VP bowstringing in cadaver fingers in the crimp grip position and to determine cut points for A3 pulley rupture. MRI in the crimp grip position was performed in 21 cadaver fingers with artificially created flexor tendon pulley tears (fingers with A3 pulley rupture n = 16, fingers without A3 pulley rupture n = 5). The distances of the translation of the VP relative to the middle phalanx base, the distances between the flexor tendons and the VP body, and the distances between the flexor tendon and bone (TB) were measured. Statistical analysis showed significantly lower VP translation distances and significantly higher VP tendon distances if the A3 pulley was ruptured. A2 TB and A4 TB distances did not differ significantly in specimens with and without A3 pulley rupture. The optimal cut points for A3 pulley rupture were a VP translation distance <2.8 mm and a VP tendon distance >1.4 mm. Reduction of the VP translation distance and augmentation of the VP tendon distance are suitable indirect signs of A3 pulley rupture. (orig.)

  18. Bone metabolism and hand grip strength response to aerobic versus resistance exercise training in non-insulin dependent diabetic patients.

    Science.gov (United States)

    Al-Shreef, Fadwa M; Al-Jiffri, Osama H; Abd El-Kader, Shehab M

    2015-09-01

    Diabetes mellitus has been shown in many studies to be associated with reduced bone mass and an increased risk of fracture. Currently, our understanding of how to use exercise effectively in diabetic patients in prevention of osteoporosis is incomplete and has prompted our interest to identify the type of effective osteogenic exercise. The aim of this study was to compare the changes in handgrip strength and bone metabolism after 6 months between aerobic and resistance exercise training in non-insulin dependent diabetic patients in Jeddah area. One hundred non-insulin dependent diabetic male patients participated in this study and were divided into two equal groups; the first group (A) received aerobic exercise training, where the second group (B) received resistance exercise training. The program consisted of three sessions per week for six months. The mean values of serum calcium and Hand grip strength were significantly increased, while the mean values of parathyroid hormone were significantly decreased in both groups .Also, there were significant differences between mean levels of the investigated parameters in group (A) and group (B) after treatment. Aerobic exercise training on treadmill is appropriate to improve markers of bone metabolism and hand grip strength in non-insulin dependent diabetic patients.

  19. Development of a global motor rating scale for young children (0-4 years) including eye-hand grip coordination.

    Science.gov (United States)

    Vaivre-Douret, L; Burnod, Y

    2001-11-01

    A comparative study of the eight motor rating scales available in Western countries demonstrated methodological differences in the choice of items and standardization. We have developed a global motor rating scale that includes items which measure postural-motor, locomotor (PML) and eye-hand grip coordination (EHGC), and which allows the assessment of an average of motor function level (MFL), PML and EHGC development. Scores obtained were used to define the acquisition of motor age based on the skills completed. The items were selected on the basis of the average age at which the function developed in two populations of healthy full-term French infants, followed from birth to 4 months (n = 60) and from 4 months to 4 years (n = 63). Recent French developmental standards (mean age and standard deviation) of acquisition allow the identification of neuro-psychomotor deviations from normal motor behaviour. This includes both static and dynamic motor coordination sequences. Inter-examiner correlations (n = 3) for 15 randomly selected children indicated a coefficient of 0.90. The scale revealed a sequence in the organization of learned postural-motor, locomotor and eye-hand gripping skills which can contribute to the understanding of brain areas implicated in this maturation process.

  20. Grounding by Attention Simulation in Peripersonal Space: Pupils Dilate to Pinch Grip But Not Big Size Nominal Classifier.

    Science.gov (United States)

    Lobben, Marit; Bochynska, Agata

    2018-03-01

    Grammatical categories represent implicit knowledge, and it is not known if such abstract linguistic knowledge can be continuously grounded in real-life experiences, nor is it known what types of mental states can be simulated. A former study showed that attention bias in peripersonal space (PPS) affects reaction times in grammatical congruency judgments of nominal classifiers, suggesting that simulated semantics may include reenactment of attention. In this study, we contrasted a Chinese nominal classifier used with nouns denoting pinch grip objects with a classifier for nouns with big object referents in a pupil dilation experiment. Twenty Chinese native speakers read grammatical and ungrammatical classifier-noun combinations and made grammaticality judgment while their pupillary responses were measured. It was found that their pupils dilated significantly more to the pinch grip classifier than to the big object classifier, indicating attention simulation in PPS. Pupil dilations were also significantly larger with congruent trials on the whole than in incongruent trials, but crucially, congruency and classifier semantics were independent of each other. No such effects were found in controls. Copyright © 2017 Cognitive Science Society, Inc.

  1. Stable isotope ratio mass spectrometry and physical comparison for the forensic examination of grip-seal plastic bags.

    Science.gov (United States)

    Taylor, Erica; Carter, James F; Hill, Jenny C; Morton, Carolyn; Daeid, Niamh Nic; Sleeman, Richard

    2008-05-20

    Plastic bags are frequently used to package drugs, explosives and other contraband. There exists, therefore, a requirement in forensic casework to compare bags found at different locations. This is currently achieved almost exclusively by the use of physical comparisons such as birefringence patterns. This paper discusses some of the advantages and shortcomings of this approach, and presents stable isotope ratio mass spectrometry (IRMS) as a supplementary tool for effecting comparisons of this nature. Carbon and hydrogen isotopic data are presented for sixteen grip-seal plastic bags from a wide range of sources, in order to demonstrate the range of values which is likely to be encountered. Both isotopic and physical comparison (specifically birefringence) techniques are then applied to the analysis of rolls of bags from different manufacturing lots from a leading manufacturer. Both approaches are able to associate bags from a common production batch. IRMS can be applied to small fragments which are not amenable to physical comparisons, and is able to discriminate bags which could be confused using birefringence patterns alone. Similarly, in certain cases birefringence patterns discriminate bags with similar isotopic compositions. The two approaches are therefore complementary. When more than one isotopically distinct region exists within a bag (e.g. the grip-seal is distinct from the body) the ability to discriminate and associate bags is greatly increased.

  2. Laterality and grip strength influence hand bone micro-architecture in modern humans, an HRpQCT study.

    Science.gov (United States)

    Reina, Nicolas; Cavaignac, Etienne; Trousdale, William H; Laffosse, Jean-Michel; Braga, José

    2017-06-01

    It is widely hypothesized that mechanical loading, specifically repetitive low-intensity tasks, influences the inner structure of cancellous bone. As such, there is likely a relationship between handedness and bone morphology. The aim of this study is to determine patterns in trabecular bone between dominant and non-dominant hands in modern humans. Seventeen healthy patients between 22 and 32 years old were included in the study. Radial carpal bones (lunate, capitate, scaphoid, trapezium, trapezoid, 1st, 2nd and 3rd metacarpals) were analyzed with high-resolution micro-computed tomography. Additionally, crush and pinch grip were recorded. Factorial analysis indicated that bone volume ratio, trabeculae number (Tb.N), bone surface to volume ratio (BS.BV), body weight, stature and crush grip were all positively correlated with principal components 1 and 2 explaining 78.7% of the variance. Volumetric and trabecular endostructural parameters (BV/TV, BS/BV or Tb.Th, Tb.N) explain the observed inter-individual variability better than anthropometric or clinical parameters. Factors analysis regressions showed correlations between these parameters and the dominant side for crush strength for the lunate (r 2 = 0.640, P modern human wrist. © 2017 Anatomical Society.

  3. Reference Values of Grip Strength Measured with a Jamar Dynamometer in 1526 Adults with Intellectual Disabilities and Compared to Adults without Intellectual Disability.

    Directory of Open Access Journals (Sweden)

    Antonio Cuesta-Vargas

    Full Text Available The aim of this study was to investigate grip strength in a large sample of people with intellectual disabilities, to establish reference values for adults with intellectual disabilities (ID and compare it to adults without intellectual disability.This study analysed pooled baseline data from two independent studies for all 1526 adults with ID: Special Olympics Funfitness Spain (n = 801 and the Dutch cross-sectional study 'Healthy aging and intellectual disabilities' (n = 725.The grip strength result of people with ID across gender and age subgroups is presented with CI95% values from higher 25.5-31.0 kg in male younger to lower 4.3-21.6 kg in female older.This study is the first to present grip strength results of a large sample of people with ID from 20-90 years of age. This study provides reference values for people with ID for use in clinical practice.

  4. Reference Values of Grip Strength Measured with a Jamar Dynamometer in 1526 Adults with Intellectual Disabilities and Compared to Adults without Intellectual Disability.

    Science.gov (United States)

    Cuesta-Vargas, Antonio; Hilgenkamp, Thessa

    2015-01-01

    The aim of this study was to investigate grip strength in a large sample of people with intellectual disabilities, to establish reference values for adults with intellectual disabilities (ID) and compare it to adults without intellectual disability. This study analysed pooled baseline data from two independent studies for all 1526 adults with ID: Special Olympics Funfitness Spain (n = 801) and the Dutch cross-sectional study 'Healthy aging and intellectual disabilities' (n = 725). The grip strength result of people with ID across gender and age subgroups is presented with CI95% values from higher 25.5-31.0 kg in male younger to lower 4.3-21.6 kg in female older. This study is the first to present grip strength results of a large sample of people with ID from 20-90 years of age. This study provides reference values for people with ID for use in clinical practice.

  5. Change in the temporal coordination of the finger joints with ulnar nerve block during different power grips analyzed with a sensor glove.

    Science.gov (United States)

    Wachter, N J; Mentzel, M; Häderer, C; Krischak, G D; Gülke, J

    2018-02-01

    Ulnar nerve injuries can cause deficient hand movement patterns. Their assessment is important for diagnosis and rehabilitation in hand surgery cases. The purpose of this study was to quantify the changes in temporal coordination of the finger joints during different power grips with an ulnar nerve block by means of a sensor glove. In 21 healthy subjects, the onset and end of the active flexion of the 14 finger joints when gripping objects of different diameters was recorded by a sensor glove. The measurement was repeated after an ulnar nerve block was applied in a standardized setting. The change in the temporal coordination of the metacarpophalangeal (MCP), proximal interphalangeal (PIP) and distal interphalangeal (DIP) joints with and without the nerve block was calculated within the same subject. In healthy subjects, the MCP joints started their movement prior to the PIP joints in the middle and ring finger, whereas this occurred in the reverse order at the index and little finger. The DIP joint onset was significantly delayed (Pblock, this coordination shifted towards simultaneous onset of all joints, independent of the grip diameter. The thumb and index finger were affected the least. With an ulnar nerve block, the PIP joints completed their movement prior to the MCP joints when gripping small objects (G1 and G2), whereas the order was reversed with larger objects (G3 and G4). The alterations with ulnar nerve block affected mainly the little finger when gripping small objects. With larger diameter objects, all fingers had a significant delay at the end of the PIP joint movement relative to the MCP and DIP joints, and the PIP and DIP joint sequence was reversed (Ppower grips, there are biomechanical effects of loss of function of the intrinsic muscles caused by an ulnar nerve block on the fine motor skills of the hand. This can be important for the diagnosis and rehabilitation of ulnar nerve lesions of the hand. Copyright © 2017 SFCM. Published by Elsevier

  6. The relationship of birthweight, muscle size at birth and postnatal growth to grip strength in 9 year-old Indian children: findings from the Mysore Parthenon Study

    Science.gov (United States)

    Barr, James G; Veena, Sargoor R; Kiran, K N; Wills, Andrew K; Winder, Nicola R; Kehoe, Sarah; Fall, Caroline HD; Sayer, Avan A; Krishnaveni, Ghattu V

    2012-01-01

    Fetal development may permanently affect muscle function. Indian newborns have a low mean birthweight, predominantly due to low lean tissue and muscle mass. We aimed to examine the relationship of birthweight, and arm muscle area (AMA) at birth and post-natal growth to hand-grip strength in Indian children. Grip strength was measured in 574 children aged 9 years, who had detailed anthropometry at birth and every 6-12 months post-natally. Mean (standard deviation (SD)) birthweight was 2863 (446) g. At 9 years, the children were short (mean height SD −0.6) and light (mean weight SD −1.1) compared with the World Health Organization growth reference. Mean (SD) grip strength was 12.7 (2.2) kg (boys) and 11.0 (2.0) kg (girls). Weight, length and AMA at birth, but not skinfold measurements at birth, were positively related to 9-year grip strength (β=0.40 kg per standard deviation increase in birthweight, p<0.001; and β=0.41 kg per standard deviation increase in AMA, p<0.001). Grip strength was positively related to 9-year height, body mass index and AMA and to gains in these measurements from birth to 2 years, 2-5 years and 5-9 years (p<0.001 for all). The associations between birth size and grip strength were attenuated but remained statistically significant for AMA after adjusting for 9-year size. We conclude that larger overall size and muscle mass at birth are associated with greater muscle strength in childhood, and that this is mediated mainly through greater post-natal size. Poorer muscle development in utero is associated with reduced childhood muscle strength. PMID:23750316

  7. Associations Between Diabetes and Both Cardiovascular Disease and All-Cause Mortality Are Modified by Grip Strength: Evidence From UK Biobank, a Prospective Population-Based Cohort Study.

    Science.gov (United States)

    Celis-Morales, Carlos A; Petermann, Fanny; Hui, Li; Lyall, Donald M; Iliodromiti, Stamatina; McLaren, James; Anderson, Jana; Welsh, Paul; Mackay, Daniel F; Pell, Jill P; Sattar, Naveed; Gill, Jason M R; Gray, Stuart R

    2017-12-01

    Grip strength and diabetes are predictors of mortality and cardiovascular disease (CVD), but whether these risk factors interact to predispose to adverse health outcomes is unknown. This study determined the interactions between diabetes and grip strength and their association with health outcomes. We undertook a prospective, general population cohort study by using UK Biobank. Cox proportional hazards models were used to explore the associations between both grip strength and diabetes and the outcomes of all-cause mortality and CVD incidence/mortality as well as to test for interactions between diabetes and grip strength. A total of 347,130 UK Biobank participants with full data available (mean age 55.9 years, BMI 27.2 kg/m 2 , 54.2% women) were included in the analysis, of which 13,373 (4.0%) had diabetes. Over a median follow-up of 4.9 years (range 3.3-7.8 years), 6,209 died (594 as a result of CVD), and 4,301 developed CVD. Participants with diabetes were at higher risk of all-cause and CVD mortality and CVD incidence. Significant interactions ( P strength. Similar results were observed for all-cause mortality and CVD incidence. Risk of adverse health outcomes among people with diabetes is lower in those with high grip strength. Low grip strength may be useful to identify a higher-risk subgroup of patients with diabetes. Intervention studies are required to determine whether resistance exercise can reduce risk. © 2017 by the American Diabetes Association.

  8. Coriolis Force

    Science.gov (United States)

    Marciuc, Daly; Solschi, Viorel

    2017-04-01

    Understanding the Coriolis effect is essential for explaining the movement of air masses and ocean currents. The lesson we propose aims to familiarize students with the manifestation of the Coriolis effect. Students are guided to build, using the GeoGebra software, a simulation of the motion of a body, related to a rotating reference system. The mathematical expression of the Coriolis force is deduced, for particular cases, and the Foucault's pendulum is presented and explained. Students have the opportunity to deepen the subject, by developing materials related to topics such as: • Global Wind Pattern • Ocean Currents • Coriolis Effect in Long Range Shooting • Finding the latitude with a Foucault Pendulum

  9. Joining Forces

    DEFF Research Database (Denmark)

    Christiansen, Anne Mette

    2013-01-01

    The interest in Corporate Social Responsibility (CSR) has grown dramatically over the last three years in Greenland. A vast geographical area with a tiny population, Greenland has recently obtained self-government status and is going through a rapid development economically and socially...... as the country moves towards embracing extractive industries (oil, gas and mining) as a path to development. Both government, civil society and business are increasingly looking for new and innovative ways of joining forces across sectors to solve some of the country's many critical social issues. Greenlandic...... companies have over the last 23 years embraced the concept of strategic CSR and are increasingly engaging in cross-sector partnerships as part of their CSR strategy. The partnerships take different forms both in regards to number of partners, focus areas and level of strategic engagement. In the article...

  10. Associations of work activities requiring pinch or hand grip or exposure to hand-arm vibration with finger and wrist osteoarthritis

    DEFF Research Database (Denmark)

    Hammer, Paula E C; Shiri, Rahman; Kryger, Ann I

    2014-01-01

    OBJECTIVE: We systematically reviewed the epidemiologic evidence linking finger and wrist osteoarthritis (OA) with work activities requiring pinch or hand grip or exposure to hand-arm vibration (HAV). METHODS: PubMed and Embase databases were searched up to June 2013. We selected studies assessin...... provide limited evidence that pinch grip may increase the risk of wrist or finger OA, but causal relation cannot be resolved because of cross-sectional designs and inadequate characterization of biomechanical strain to the hand and wrist....

  11. Management of displaced inferior patellar pole fractures with modified tension band technique combined with cable cerclage using Cable Grip System.

    Science.gov (United States)

    Yang, Xu; Wu, Qinfen; Lai, Chin-Hui; Wang, Xin

    2017-10-01

    We present a modified tension band technique combined with cable cerclage using Cable Grip System for the treatment of displaced inferior patellar pole fractures and report the knee functional outcome. The patients who had had operative treatment of a displaced inferior patellar pole fracture (AO/OTA 34-A1) between December 2013 and December 2015 were studied retrospectively. Eleven consecutive patients had had open reduction and internal fixation with the modified technique using Cable Grip System, of whom, five males and six females with an average age of 60.9 years (range, 29-81 years). All fractures occurred from direct fall onto the knee. The average time from injury to surgery was 6.1days (range, 2-12days). The range of motion (ROM) was measured in degrees by goniometry at postoperative intervals of 1, 2, 4, 12, and 48 weeks; Knee function was evaluated using the Rasmussen scores at final follow-up. No patients had nonunion, loss of reduction, migration of wire, irritation from the implant and fixation breakage during the follow-up period. Recovery of ROM was achieved at 12 weeks, with the average ROM at 1 week was 72° (range, 65°-78°), 86.4° (range, 78°-92°) at 2 weeks, 115.5° (range, 103°-122°) at 4 weeks, 129.6° (range, 122°-133°) at 12 weeks, 134.5° (range, 129°-139°) at 48 weeks after the operation. Concerning the knee function outcome assessment, all patients showed excellent results at final follow-up. The average Rasmussen scores was 27.9 out of 30 (range, 27-29). The modified tension band technique combined with cable cerclage using Cable Grip System for displaced inferior patellar pole fractures can provide stable fixation with excellent results in knee function, allows for immediate mobilization and early weight-bearing, which is a simple and valuable technique in routine clinical practice. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Medial Elbow Joint Space Increases With Valgus Stress and Decreases When Cued to Perform A Maximal Grip Contraction.

    Science.gov (United States)

    Pexa, Brett S; Ryan, Eric D; Myers, Joseph B

    2018-04-01

    Previous research indicates that the amount of valgus torque placed on the elbow joint during overhead throwing is higher than the medial ulnar collateral ligament (UCL) can tolerate. Wrist and finger flexor muscle activity is hypothesized to make up for this difference, and in vitro studies that simulated activity of upper extremity musculature, specifically the flexor digitorum superficialis and flexor carpi ulnaris, support this hypothesis. To assess the medial elbow joint space at rest, under valgus stress, and under valgus stress with finger and forearm flexor contraction by use of ultrasonography in vivo. Controlled laboratory study. Participants were 22 healthy males with no history of elbow dislocation or UCL injury (age, 21.25 ± 1.58 years; height, 1.80 ± 0.08 m; weight, 79.43 ± 18.50 kg). Medial elbow joint space was measured by use of ultrasonography during 3 separate conditions: at rest (unloaded), under valgus load (loaded), and with a maximal grip contraction under a valgus load (loaded-contracted) in both limbs. Participants lay supine with their arm abducted 90° and elbow flexed 30° with the forearm in full supination. A handgrip dynamometer was placed in the participants' hand to grip against during the contracted condition. Images were reduced in ImageJ to assess medial elbow joint space. A 2-way (condition × limb) repeated-measures analysis of variance and Cohen's d effect sizes were used to assess changes in medial elbow joint space. Post hoc testing was performed with a Bonferroni adjustment to assess changes within limb and condition. The medial elbow joint space was significantly larger in the loaded condition (4.91 ± 1.16 mm) compared with the unloaded condition (4.26 ± 1.23 mm, P space increases under a valgus load and then decreases when a maximal grip contraction is performed. This indicates that wrist and finger flexor muscle contraction may assist in limiting medial elbow joint space, a result similar to findings of previous

  13. The Association Between Knee Extensor Force Steadiness, Force Accuracy, and Mobility in Older Adults Who Have Fallen.

    Science.gov (United States)

    Chung-Hoon, Kaiwi; Tracy, Brian L; Dibble, Leland E; Marcus, Robin L; Burgess, Paul; LaStayo, Paul C

    2016-01-01

    Older adults often experience limited mobility, lower extremity muscle weakness, and increased fall risk. Furthermore, when older adults perform tasks that require control of submaximal force, impairments in their ability to maintain steady and accurate force output have been reported. Such problems may be related to deteriorating levels of mobility, particularly in older adults who have fallen. The purpose of this study was to determine whether an association exists between muscle force steadiness (MFS) or muscle force accuracy (MFA) of the knee extensors and mobility in older adults who have fallen. Twenty older adults ((Equation is included in full-text article.)= 77.5 ± 7 years, 5 males and 15 females) with 2 or more comorbid conditions and who experienced a fall in the past year underwent assessment of maximal voluntary isometric contraction of the knee extensors. A submaximal target force of 50% of their maximal voluntary isometric contraction was used to determine concentric and eccentric (ECC) steadiness (the fluctuations in force production) and accuracy (the average distance of the mean force from the target force) measures. Mobility was indicated by the 6-minute walk test, the Timed Up and Go, stair ascent, and stair descent tests. Correlation analysis was used to assess the relationship between measures of muscle force control and mobility. The correlations between muscle force steadiness and mobility were not significant (P > .05) for either contraction type. However, MFA during ECC contractions only was correlated significantly with all measures of mobility-6 minute walk test (r = -0.48; P = .03), Timed Up and Go (r = 0.68; P = .01), stair ascent (r = 0.60; P = .01), and stair descent (r = 0.75; P fallen is novel. Although the correlations are not causal, these relationships suggest that inaccurate force output during ECC contractions of the knee extensors is linked to impaired mobility.

  14. Lower Extremity Strength and Hopping and Jumping Ground Reaction forces in Children with Neurofibromatosis Type 1

    Science.gov (United States)

    Johnson, Barbara; MacWilliams, Bruce; Carey, John C.; Viskochil, David H.; D’Astous, Jacques L.; Stevenson, David A.

    2011-01-01

    The purpose of this study was to 1) extend the research findings of decreased muscular force production in grip strength to the lower extremity strength of children with NF1 and 2) to determine if there was a relationship between isometric strength and functional activities in children with NF1. Force production was assessed using a hand held dynamometer (HHD) and a functional task (hopping and jumping) on a force plate. Data from twenty-six children with NF1 were compared to data from 48 typically developing children of similar sex, weight and height. Children with NF1 demonstrated statistically significant lower force production with HHD (pdynamometry is useful for determining a relationship between common clinical measures and functional activities. PMID:21906829

  15. Coming to Grips with Farmers' variety Selection- the Case of New Improved Rice Varieties under Irrigation in South East Tanzania

    Directory of Open Access Journals (Sweden)

    Kafiriti, EM.

    2003-01-01

    Full Text Available In collaboration with farmers, rice varieties were evaluated under small-scale irrigation in two villages of south east Tanzania for two consecutive cropping seasons (1999/2000 –2000/2001. The objectives were to give farmers access to new improved rice varieties; to identify the selection criteria farmers consider important in irrigated rice production; and to come to grips with their arguments. Farmers were provided with eleven improved varieties, which they compared with their own ones. Farmers' preferred varieties with short to medium maturity period, which produce many tillers and mature uniformly; and with long translucent aromatic grains for their own use and marketing. This study identified qualitative and quantitative evaluation criteria which farmers are using for selecting rice varieties. The implication for further research on rice in south east Tanzania is that the breeding programme should incorporate these attributes to address farmers' preferences, rather than to go for absolute maximum yield levels.

  16. Reference values of grip strength measured with a Jamar dynamometer in 1526 adults with intellectual disabilities and compared to adults without intellectual disability

    NARCIS (Netherlands)

    Cuesta-Vargas, A. (Antonio); T.I.M. Hilgenkamp (Thessa)

    2015-01-01

    textabstractAim: The aim of this study was to investigate grip strength in a large sample of people with intellectual disabilities, to establish reference values for adults with intellectual disabilities (ID) and compare it to adults without intellectual disability. Methods: This study analysed

  17. Practice effects in bimanual force control: does age matter?

    Science.gov (United States)

    Vieluf, Solveig; Godde, Ben; Reuter, Eva-Maria; Temprado, Jean-Jacques; Voelcker-Rehage, Claudia

    2015-01-01

    The authors examined age-related differences in fine motor control during a bimanual coordination task. The task required the modulation of fingertip forces in the precision grip according to a visually presented sinusoidal antiphase pattern (force range 2-12 N; frequency 0.2 Hz). Thirty-four right-handed participants of three age groups (young, early middle-aged, and late middle-aged) practiced 30 trials of the task. Accuracy and variability of relative timing and relative forces at minima and maxima of the sine wave were analyzed for hand-hand and hand-stimulus couplings and compared between age groups. Analysis showed for relative timing and force weaker hand-hand than hand-stimulus coupling as well as lower accuracy and higher variability for minima as compared to maxima. Further, we analyzed practice effects by comparing the first and last trials and characterized the course of practice by detecting the transition of a steeper to a shallower acquisition slope for the different age groups. Late middle-aged participants demonstrated poorer performance than both other groups for all parameters. All groups improved performance to a similar amount. However, an age-related difference in acquisition strategy is visible. Late middle-aged participants seemed to have focused on improvement of force amplitude, whereas young and early middle-aged focused on timing.

  18. Microscopic vision modeling method by direct mapping analysis for micro-gripping system with stereo light microscope.

    Science.gov (United States)

    Wang, Yuezong; Zhao, Zhizhong; Wang, Junshuai

    2016-04-01

    We present a novel and high-precision microscopic vision modeling method, which can be used for 3D data reconstruction in micro-gripping system with stereo light microscope. This method consists of four parts: image distortion correction, disparity distortion correction, initial vision model and residual compensation model. First, the method of image distortion correction is proposed. Image data required by image distortion correction comes from stereo images of calibration sample. The geometric features of image distortions can be predicted though the shape deformation of lines constructed by grid points in stereo images. Linear and polynomial fitting methods are applied to correct image distortions. Second, shape deformation features of disparity distribution are discussed. The method of disparity distortion correction is proposed. Polynomial fitting method is applied to correct disparity distortion. Third, a microscopic vision model is derived, which consists of two models, i.e., initial vision model and residual compensation model. We derive initial vision model by the analysis of direct mapping relationship between object and image points. Residual compensation model is derived based on the residual analysis of initial vision model. The results show that with maximum reconstruction distance of 4.1mm in X direction, 2.9mm in Y direction and 2.25mm in Z direction, our model achieves a precision of 0.01mm in X and Y directions and 0.015mm in Z direction. Comparison of our model with traditional pinhole camera model shows that two kinds of models have a similar reconstruction precision of X coordinates. However, traditional pinhole camera model has a lower precision of Y and Z coordinates than our model. The method proposed in this paper is very helpful for the micro-gripping system based on SLM microscopic vision. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Tongue Strength is Associated with Grip Strength and Nutritional Status in Older Adult Inpatients of a Rehabilitation Hospital.

    Science.gov (United States)

    Sakai, Kotomi; Nakayama, Enri; Tohara, Haruka; Maeda, Tomomi; Sugimoto, Motonobu; Takehisa, Takahiro; Takehisa, Yozo; Ueda, Koichiro

    2017-04-01

    The aim of this cross-sectional study was to investigate whether tongue strength observed in older adult inpatients of a rehabilitation hospital is associated with muscle function, nutritional status, and dysphagia. A total of 174 older adult inpatients aged 65 years and older in rehabilitation (64 men, 110 women; median age, 84 years; interquartile range, 80-89 years) who were suspected of having reduced tongue strength due to sarcopenia were included in this study. Isometric tongue strength was measured using a device fitted with a disposable oral balloon probe. We evaluated age, muscle function as assessed by the Barthel index and grip strength, nutritional status as measured by the Mini Nutritional Assessment-short form (MNA-SF), body mass index, serum albumin, controlling nutritional status, and calf circumference and arm muscle area to assess muscle mass. In addition, the functional oral intake scale (FOIS) was used as an index of dysphagia. Multivariate linear regression analysis revealed that isometric tongue strength was independently associated with grip strength (coefficient = 0.33, 95 % confidence interval (CI) 0.12-0.54, p = 0.002), MNA-SF (coefficient = 0.74, 95 % CI 0.12-1.35, p = 0.019), and FOIS (coefficient = 0.02, 95 % CI 0.00-0.15, p = 0.047). To maintain and improve tongue strength in association with sarcopenic dysphagia, exercise therapy and nutritional therapy interventions, as well as direct interventions to address tongue strength, may be effective in dysphagia rehabilitation in older adult inpatients.

  20. Digit forces bias sensorimotor transformations underlying control of fingertip position

    Science.gov (United States)

    Shibata, Daisuke; Kappers, Astrid M. L.; Santello, Marco

    2014-01-01

    Humans are able to modulate digit forces as a function of position despite changes in digit placement that might occur from trial to trial or when changing grip type for object manipulation. Although this phenomenon is likely to rely on sensing the position of the digits relative to each other and the object, the underlying mechanisms remain unclear. To address this question, we asked subjects (n = 30) to match perceived vertical distance between the center of pressure (CoP) of the thumb and index finger pads (dy) of the right hand (“reference” hand) using the same hand (“test” hand). The digits of reference hand were passively placed collinearly (dy = 0 mm). Subjects were then asked to exert different combinations of normal and tangential digit forces (Fn and Ftan, respectively) using the reference hand and then match the memorized dy using the test hand. The reference hand exerted Ftan of thumb and index finger in either same or opposite direction. We hypothesized that, when the tangential forces of the digits are produced in opposite directions, matching error (1) would be biased toward the directions of the tangential forces; and (2) would be greater when the remembered relative contact points are matched with negligible digit force production. For the test hand, digit forces were either negligible (0.5–1 N, 0 ± 0.25 N; Experiment 1) or the same as those exerted by the reference hand (Experiment 2).Matching error was biased towards the direction of digit tangential forces: thumb CoP was placed higher than the index finger CoP when thumb and index finger Ftan were directed upward and downward, respectively, and vice versa (p forces. We propose that the expected sensory consequence of motor commands for tangential forces in opposite directions overrides estimation of fingertip position through haptic sensory feedback. PMID:25136304

  1. INDICATORS OF MAXIMAL FLEXOR FORCE OF LEFT AND RIGHT HAND FOR THE POLICE SELECTION CRITERIA PURPOSES

    Directory of Open Access Journals (Sweden)

    Milivoj Dopsaj

    2006-06-01

    Full Text Available As a part of their professional responsibilities, police officers have authorization, in situation determined by law, to apply physical force or means of force. Due to given professional reasons, selection among the candidates as well as routine physical capability assessments, should have professional-methodological basis and scientific foundation. Muscle groups of particular reference in relationship to estimate general contraction characteristic in regard to force, and at the same time very easy to test are flexor muscles of fingers of the hand (test “hand squeeze”. The aim of this research is to define criterion characteristic for the population to function for selection and estimation of the hand squeeze force among policemen. This research had 723 participants, students of the Police Academy, as representatives of policemen between 19 and 24 years of age. In order to estimate force of hand grip (both right and left hand, we utilized tensiometric method, and standard procedure previously described (1. For the statistical analysis we used basic descriptive analysis, cluster analysis (defining 7 characteristic classes (clusters as a function of population tested –unacceptable, poor, below average, averaged, above average, excellent and superior, and factor analysis (definition of the selection test as a function of selection procedure (10. Our results indicate that averaged hand grip force among the tested population is 61.70±8.97 DaN (Min – Max=43.43-101.41 for left hand, and 65.11±9.34 DaN (Min – Max= 46.54-109.75 for right hand. The values for the force of defined cluster centers of left hand are: Cluster1-7=50.22, 55.76, 61.61, 67.84, 74.71, 84.02 and 97.15 DaN, and right hand are: Cluster1-7=53.40, 60.27, 66.10, 72.20, 79.70, 92.55 and 105.65 DaNFactor analysis results have shown that one factor has been isolated that accounted for 91.10 worthy variance. Regarding the individual variability, for the saturation of the isolated

  2. Dynamometry for the measurement of grip, pinch, and trunk muscles strength in subjects with subacute stroke: reliability and different number of trials.

    Science.gov (United States)

    Aguiar, Larissa T; Martins, Júlia C; Lara, Eliza M; Albuquerque, Julianna A; Teixeira-Salmela, Luci F; Faria, Christina D C M

    2016-07-11

    Muscle strength is usually measured in individuals with stroke with Portable dynamometers (gold standard). However, no studies have investigated the reliability, the standard error of measurement (SEM) and the minimal detectable difference (MDD95%) of the dynamometry for the measurement of hand grip, pinch grip and trunk strength in subjects with subacute stroke. 1) To investigate the intra and inter-rater reliability, the SEM and the MDD95% of the portable dynamometers for the measurement of grip, pinch and trunk strength in subjects with subacute stroke, and 2) to verify whether the use of different number of trials (first trial and the average of the first two and three trials) affected the results. 32 subjects with subacute stroke (time since stroke onset: 3.6 months, SD=0.66 months) were evaluated. Hand grip, 3 pinch grips (i.e. pulp-to-pulp/palmar/lateral) and 4 trunk muscles (i.e. flexors, extensors, lateral flexors and rotators) strength were bilaterally assessed (except trunk flexors/extensors) with portable dynamometry by two independent examiners over two sessions (1-2 weeks apart). One-way ANOVAs and intraclass correlation coefficients (ICC2,k) were used for analysis (α=0.05). SEM and MDD95% were also calculated. For all muscular groups and sources of outcome values, including one trial, after familiarization, similar results were found (0.01≤F≤0.08; 0.92≤p≤0.99) with significant and adequate values of intra-rater (0.64≤ICC≤0.99; 0.23≤95%CI≤0.99) and inter-rater (0.66≤ICC≤0.99; 0.25≤95%CI≤0.99) reliability. SEM and MDD95% were considered low (0.39≤EPM≤2.21 Kg; 0.96≤MMD95%≤6.12 Kg) for all outcome scores. Only one trial, following familiarization, demonstrated adequate intra-rater and inter-rater reliability of the portable dynamometers for the measurement of hand grip, pinch grip and trunk strength in subjects with subacute stroke.

  3. Finger Flexor Force Influences Performance in Senior Male Air Pistol Olympic Shooting.

    Directory of Open Access Journals (Sweden)

    Daniel Mon

    Full Text Available The ability to stabilize the gun is crucial for performance in Olympic pistol shooting and is thought to be related to the shooters muscular strength. The present study examines the relation between performance and finger flexor force as well as shoulder abduction isometric force in senior male air pistol shooting. 46 Spanish national level shooters served as test subjects of the study. Two maximal force tests were carried out recording handgrip and deltoid force data under competition conditions, during the official training time at national Spanish championships. Performance was measured as the total score of 60 shots at competition. Linear regressions were calculated to examine the relations between performance and peak and average finger flexor forces, peak and average finger flexor forces relative to the BMI, peak and average shoulder abduction isometric forces, peak shoulder abduction isometric force relative to the BMI. The connection between performance and other variables such as age, weight, height, BMI, experience in years and training hours per week was also analyzed. Significant correlations were found between performance at competition and average and peak finger flexor forces. For the rest of the force variables no significant correlations were found. Significant correlations were also found between performance at competition and experience as well as training hours. No significant correlations were found between performance and age, weight, height or BMI. The study concludes that hand grip strength training programs are necessary for performance in air pistol shooting.

  4. Models and control for force/torque sensors in robotics

    International Nuclear Information System (INIS)

    Johansson, Gert.

    1992-01-01

    One of the important problems in automatic assembly is the relative positioning accuracy between the parts in the assembly process. Inaccurate positions cause large insertion forces, wear and might damage the parts. They can also completely disable the assembly process. A solution to this problem is to detect the positioning error and to make a relevant adjustment of the position or path. This thesis presents a solution based on active feedback of force/torque data from a wrist mounted sensor. A task independent control algorithm has been realized through a sensor model concept. The sensor model includes an algorithm that transforms force/torque input to relevant motion of the end effector. The transformation is specified by a set of parameters e.g. desired forces, compliance and stopping criteria. The problem with gravity forces for varying end effector orientation is compensated by an algorithm, divided into three complexity levels. The compensation method includes a calibration sequence to ensure valid end effector properties to be used in the algorithm. A problem with available robot technology is bad integration possibilities for external sensors. To allow necessary modifications and expansions, an open and general control system architecture is proposed. The architecture is based in a computer workstation and transputers in pipeline for the robot specific operations. (au)

  5. Factors influencing power hand tool fastening accuracy and reaction forces.

    Science.gov (United States)

    Radwin, Robert G; Chourasia, Amrish O; Howery, Robert S; Fronczak, Frank J; Yen, Thomas Y; Subedi, Yashpal; Sesto, Mary E

    2014-06-01

    A laboratory study investigated the relationship between power hand tool and task-related factors affecting threaded fastener torque accuracy and associated handle reaction force. We previously developed a biodynamic model to predict handle reaction forces. We hypothesized that torque accuracy was related to the same factors that affect operator capacity to react against impulsive tool forces, as predicted by the model. The independent variables included tool (pistol grip on a vertical surface, right angle on a horizontal surface), fastener torque rate (hard, soft), horizontal distance (30 cm and 60 cm), and vertical distance (80 cm, 110 cm, and 140 cm). Ten participants (five male and five female) fastened 12 similar bolts for each experimental condition. Average torque error (audited - target torque) was affected by fastener torque rate and operator position. Torque error decreased 33% for soft torque rates, whereas handle forces greatly increased (170%). Torque error also decreased for the far horizontal distance 7% to 14%, when vertical distance was in the middle or high, but handle force decreased slightly 3% to 5%. The evidence suggests that although both tool and task factors affect fastening accuracy, they each influence handle reaction forces differently. We conclude that these differences are attributed to different parameters each factor influences affecting the dynamics of threaded faster tool operation. Fastener torque rate affects the tool dynamics, whereas posture affects the spring-mass-damping biodynamic properties of the human operator. The prediction of handle reaction force using an operator biodynamic model may be useful for codifying complex and unobvious relationships between tool and task factors for minimizing torque error while controlling handle force.

  6. Correlation of force control with regional spinal DTI in patients with cervical spondylosis without signs of spinal cord injury on conventional MRI.

    Science.gov (United States)

    Lindberg, Påvel G; Sanchez, Katherine; Ozcan, Fidan; Rannou, François; Poiraudeau, Serge; Feydy, Antoine; Maier, Marc A

    2016-03-01

    The aim of this study was to investigate spinal cord structure in patients with cervical spondylosis where conventional MRI fails to reveal spinal cord damage. We performed a cross-sectional study of patients with cervical spondylosis without conventional MRI findings of spinal cord damage and healthy controls. Subjects were studied using spinal diffusion tensor imaging (DTI), precision grip and foot force-tracking tasks, and a clinical examination including assessment of neurological signs. A regional analysis of lateral and medial spinal white matter across multiple cervical levels (C1-C5) was performed. DTI revealed reduced fractional anisotropy (FA) and increased radial diffusivity (RD) in the lateral spinal cord at the level of greatest compression (lowest Pavlov ratio) in patients (p spondylosis had greater error and longer release duration in both grip and foot force-tracking. Similar spinal cord deficits were present in patients without neurological signs. Increased error in grip and foot tracking (low accuracy) correlated with increased RD in the lateral spinal cord at the level of greatest compression (p ≤ 0.01). Spinal DTI can detect subtle spinal cord damage of functional relevance in cervical spondylosis, even in patients without signs on conventional T2-imaging and without neurological signs. DTI reveals spinal cord changes in cervical spondylosis with few symptoms. DTI changes were present despite normal spinal cord on conventional MRI. DTI parameters correlated with force control accuracy in hand and foot. Spinal DTI is a promising technique for patients with cervical spondylosis.

  7. Study of the effects of the hand grip and finger strengths on the friction and petrissage - the massage manipulations - of the students who take massage courses: Kütahya City example

    Directory of Open Access Journals (Sweden)

    Erzeybek Mustafa Said

    2016-01-01

    Full Text Available In this research, the effect of the hand grip and finger strengths on the power development between the friction and petrissage techniques - the massage manipulations - have been studied. To the study that has been structured as a single group pretest/post test, 36 healthy males who are the students of the University of Dumlupınar, Academy of Physical Education and Sports and who take massage courses (age = 19.72 ± 1.56 years (average ± Sd have been included. The practical massage course has continued for 12 weeks, two days a week for a total of one hour and the hand grip strength of both hands (right hand grip strength = RHG, left hand grip strength = LHG and the grip strength of both fingers (right finger strength = RF, left finger strength = LF have been recorded at the beginning. For the measurements carried out before and later of the study with regard to the hand grip strength, a Takkei branded hand dynamometer and with regard to the finger grip strength a (baseline branded pinch meter have been used. All measurements have been repeated twice and for the analysis, the average values obtained from two deads have been used. For statistical analysis, with regard to the changes in the pre test-post test finger strength and hand grip strength, paired-samples t test has been used. The significance limit has been defined as p0.05. It is possible to report that massaging regularly with both hands is efficient for the development of the finger and hand grip strengths; especially, with regard to the friction (circular movements that are generally carried out with fingers and petrissage (kneading that is generally carried out with the palm techniques.

  8. Effects of carpal tunnel syndrome on adaptation of multi-digit forces to object weight for whole-hand manipulation.

    Directory of Open Access Journals (Sweden)

    Wei Zhang

    Full Text Available The delicate tuning of digit forces to object properties can be disrupted by a number of neurological and musculoskeletal diseases. One such condition is Carpal Tunnel Syndrome (CTS, a compression neuropathy of the median nerve that causes sensory and motor deficits in a subset of digits in the hand. Whereas the effects of CTS on median nerve physiology are well understood, the extent to which it affects whole-hand manipulation remains to be addressed. CTS affects only the lateral three and a half digits, which raises the question of how the central nervous system integrates sensory feedback from affected and unaffected digits to plan and execute whole-hand object manipulation. We addressed this question by asking CTS patients and healthy controls to grasp, lift, and hold a grip device (445, 545, or 745 g for several consecutive trials. We found that CTS patients were able to successfully adapt grip force to object weight. However, multi-digit force coordination in patients was characterized by lower discrimination of force modulation to lighter object weights, higher across-trial digit force variability, the consistent use of excessively large digit forces across consecutive trials, and a lower ability to minimize net moments on the object. Importantly, the mechanical requirement of attaining equilibrium of forces and torques caused CTS patients to exert excessive forces at both CTS-affected digits and digits with intact sensorimotor capabilities. These findings suggest that CTS-induced deficits in tactile sensitivity interfere with the formation of accurate sensorimotor memories of previous manipulations. Consequently, CTS patients use compensatory strategies to maximize grasp stability at the expense of exerting consistently larger multi-digit forces than controls. These behavioral deficits might be particularly detrimental for tasks that require fine regulation of fingertip forces for manipulating light or fragile objects.

  9. Estimation of Handgrip Force from SEMG Based on Wavelet Scale Selection.

    Science.gov (United States)

    Wang, Kai; Zhang, Xianmin; Ota, Jun; Huang, Yanjiang

    2018-02-24

    This paper proposes a nonlinear correlation-based wavelet scale selection technology to select the effective wavelet scales for the estimation of handgrip force from surface electromyograms (SEMG). The SEMG signal corresponding to gripping force was collected from extensor and flexor forearm muscles during the force-varying analysis task. We performed a computational sensitivity analysis on the initial nonlinear SEMG-handgrip force model. To explore the nonlinear correlation between ten wavelet scales and handgrip force, a large-scale iteration based on the Monte Carlo simulation was conducted. To choose a suitable combination of scales, we proposed a rule to combine wavelet scales based on the sensitivity of each scale and selected the appropriate combination of wavelet scales based on sequence combination analysis (SCA). The results of SCA indicated that the scale combination VI is suitable for estimating force from the extensors and the combination V is suitable for the flexors. The proposed method was compared to two former methods through prolonged static and force-varying contraction tasks. The experiment results showed that the root mean square errors derived by the proposed method for both static and force-varying contraction tasks were less than 20%. The accuracy and robustness of the handgrip force derived by the proposed method is better than that obtained by the former methods.

  10. An optical 6-axis force sensor for brain function analysis using fMRI

    International Nuclear Information System (INIS)

    Takahashi, Norihisa; Tada, Mitsunori; Ueda, Jun; Matsumoto, Yoshio; Ogasawara, Tsukasa

    2004-01-01

    This paper presents an 6-axis optical force sensor which can be used in functional MRI (fMRI). Recently, fMRI are widely used for studying human brain function. Simultaneous measurement of brain activity and peripheral information, such as grip force, enables more precise investigations in studies of motor function. However, conventional force sensors cannot be used in fMRI environment, since metal elements generate noise which severely contaminate the signals of fMRI. An optical 2-axis force sensor has been developed using photo sensors and optical fibers by Tada et al., that resolved these problems. The developed force sensor removed all magnetic components from the sensing part. It detected minute displacements by measure amount of light and light traveled through the optical fibers. However, there still remain several problems on this optical force sensor. Firstly, the accuracy is not high compared to the conventional force sensors. Secondly, the robustness is not enough against the contact force to the optical fibers. In this paper, the problems concerning to the acturacy and the sensor output stability has been improved by novel methods of fixing fibers and arithmetic circuit. An optical 6-axis force is developed based on these improvements, and usefulness of our sensor for brain function analysis is confirmed in fMRI experimentations. (author)

  11. Why 1D electrical resistivity techniques can result in inaccurate siting of boreholes in hard rock aquifers and why electrical resistivity tomography must be preferred: the example of Benin, West Africa

    Science.gov (United States)

    Alle, Iboukoun Christian; Descloitres, Marc; Vouillamoz, Jean-Michel; Yalo, Nicaise; Lawson, Fabrice Messan Amen; Adihou, Akonfa Consolas

    2018-03-01

    Hard rock aquifers are of particular importance for supplying people with drinking water in Africa and in the world. Although the common use of one-dimensional (1D) electrical resistivity techniques to locate drilling site, the failure rate of boreholes is usually high. For instance, about 40% of boreholes drilled in hard rock aquifers in Benin are unsuccessful. This study investigates why the current use of 1D techniques (e.g. electrical profiling and electrical sounding) can result in inaccurate siting of boreholes, and checks the interest and the limitations of the use of two-dimensional (2D) Electrical Resistivity Tomography (ERT). Geophysical numerical modeling and comprehensive 1D and 2D resistivity surveys were carried out in hard rock aquifers in Benin. The experiments carried out at 7 sites located in different hard rock groups confirmed the results of the numerical modeling: the current use of 1D techniques can frequently leads to inaccurate siting, and ERT better reveals hydrogeological targets such as thick weathered zone (e.g. stratiform fractured layer and preferential weathering associated with subvertical fractured zone). Moreover, a cost analysis demonstrates that the use of ERT can save money at the scale of a drilling programme if ERT improves the success rate by only 5% as compared to the success rate obtained with 1D techniques. Finally, this study demonstrates, using the example of Benin, that the use of electrical resistivity profiling and sounding for siting boreholes in weathered hard rocks of western Africa should be discarded and replaced by the use of ERT technique, more efficient.

  12. Handbook of force transducers

    CERN Document Server

    Stefanescu, Dan Mihai

    2011-01-01

    Part I introduces the basic ""Principles and Methods of Force Measurement"" acording to a classification into a dozen of force transducers types: resistive, inductive, capacitive, piezoelectric, electromagnetic, electrodynamic, magnetoelastic, galvanomagnetic (Hall-effect), vibrating wires, (micro)resonators, acoustic and gyroscopic. Two special chapters refer to force balance techniques and to combined methods in force measurement. Part II discusses the ""(Strain Gauge) Force Transducers Components"", evolving from the classical force transducer to the digital / intelligent one, with the inco

  13. Polymer micro-grippers with an integrated force sensor for biological manipulation

    International Nuclear Information System (INIS)

    Mackay, R E; Le, H R; Clark, S; Williams, J A

    2013-01-01

    The development of a novel micro-system integrating SU-8 polymer micro-grippers with a tensile force sensor for handling and characterizing the mechanical properties of delicate biological materials, such as fibrils, is presented. The micro-grippers are actuated by the electro-thermal effect and have gripping forces comparable to the common ‘hot-and-cold-arm’ grippers. A robust finite element model was developed to investigate system performance and validated experimentally. A new micro-mechanical calibration method using a piezoelectric manipulator with a micro-force measurement system was successfully applied to test the structure. Both FEA simulation and micro-mechanical testing results indicated that the system could fulfil the requirements for micro-object manipulation within a biological environment. (paper)

  14. A study of wave forces on an offshore platform by direct CFD and Morison equation

    Directory of Open Access Journals (Sweden)

    Zhang D.

    2015-01-01

    The next step is the presentation of 3D multiphase RANS simulation of the wind-turbine platform in single-harmonic regular waves. Simulation results from full 3D simulation will be compared to the results from Morison’s equation. We are motivated by the challenges of a floating platform which has complex underwater geometry (e.g. tethered semi-submersible. In cases like this, our hypothesis is that Morison’s equation will result in inaccurate prediction of forces, due to the limitations of 2D coefficients of simple geometries, and that 3D multiphase RANS CFD will be required to generate reliable predictions of platform loads and motions.

  15. Drip, ship, and grip, then slice and dice: Comprehensive stroke center management of cervical and intracranial emboli.

    Directory of Open Access Journals (Sweden)

    Jason D Hinman

    2013-07-01

    Full Text Available BACKGROUND AND PURPOSE: Tandem acute thrombotic emboli in the cervical and intracranial arteries are an unusual case of stroke presenting unique management challenges. In regional systems of acute stroke care anchored by Comprehensive Stroke Centers, combined fibrinolytic, endovascular, and open surgical intervention is a new therapeutic option. SUMMARY OF CASE: A 28 year old male underwent retinal surgery, including post-operative neck compression and the next day presented to a primary stroke center with aphasia and right hemiplegia. Intravenous tissue plasminogen activator therapy was initiated and the patient was transferred to a comprehensive stroke center (CSC for higher level of care (drip and ship. Imaging at the CSC demonstrated tandem thrombi: a near occlusive lesion at the origin of the left cervical internal carotid artery and a total occlusion of the M1 segment of the left middle cerebral artery. Endovascular thrombectomy with the Solitaire stent retriever resulted in intracranial recanalization (grip. Immediately after the endovascular procedure, open carotid thrombectomy was performed to achieve cervical carotid revascularization without systemic heparinization (slice. Both cervical carotid and intracranial thrombi were processed for proteomic analysis via mass spectrometry (dice. CONCLUSION: Combined fibrinolytic, endovascular, and open surgical intervention can yield revascularization and good clinical outcome in cases of tandem lesions.

  16. Degree, but not direction of grip strength asymmetries, is related to depression and anxiety in an elderly population.

    Science.gov (United States)

    Yu, Junhong; Rawtaer, Iris; Mahendran, Rathi; Kua, Ee-Heok; Feng, Lei

    2017-05-01

    Despite the abundance of studies on asymmetries in manual laterality, a marker for atypical brain lateralization in depression and anxiety, findings in this area are mixed. Traditionally, research have looked at individual differences in depression and anxiety as a function of the direction of asymmetry. However, recent research has emphasized on studying the degree of asymmetry in addition to its direction. To these ends, the present study aims to unravel the associations between the degree and direction of manual lateralization, and depression/anxiety. Cognitively healthy elderlies (N = 326, 91 males, M age  = 68) were administered grip strength assessments on both hands and self-report measures of depression and anxiety. Partial correlation analyses controlling for age, education and sex revealed significant positive associations between degree of lateralization and anxiety in the overall sample and among right-dominant participants, as well as a significant positive relationship between degree of lateralization and depression among right-dominant participants. None of the correlations involving the direction of lateralization yielded significance, neither was there significant differences between left- and right-dominant participants on depression and anxiety scores. These findings suggest that the degree of manual lateralization, but not direction, is related to depression and anxiety at least among right-dominant individuals.

  17. Reference Values of Grip Strength Measured with a Jamar Dynamometer in 1526 Adults with Intellectual Disabilities and Compared to Adults without Intellectual Disability

    OpenAIRE

    Cuesta-Vargas, Antonio; Hilgenkamp, Thessa

    2015-01-01

    textabstractAim: The aim of this study was to investigate grip strength in a large sample of people with intellectual disabilities, to establish reference values for adults with intellectual disabilities (ID) and compare it to adults without intellectual disability. Methods: This study analysed pooled baseline data from two independent studies for all 1526 adults with ID: Special Olympics Funfitness Spain (n = 801) and the Dutch cross-sectional study 'Healthy aging and intellectual disabiliti...

  18. StringForce

    DEFF Research Database (Denmark)

    Barendregt, Wolmet; Börjesson, Peter; Eriksson, Eva

    2017-01-01

    In this paper, we present the forced collaborative interaction game StringForce. StringForce is developed for a special education context to support training of collaboration skills, using readily available technologies and avoiding the creation of a "mobile bubble". In order to play StringForce ...

  19. Sustained effect of resistance training on blood pressure and hand grip strength following a detraining period in elderly hypertensive women: a pilot study.

    Science.gov (United States)

    Nascimento, Dahan da Cunha; Tibana, Ramires Alsamir; Benik, Franklin M; Fontana, Keila Elizabeth; Ribeiro Neto, Frederico; Santana, Frederico Santos de; Santos-Neto, Leopoldo; Silva, Renato André Sousa; Silva, Alessandro Oliveira; Farias, Darlan Lopes; Balsamo, Sandor; Prestes, Jonato

    2014-01-01

    Hypertension is the most prevalent modifiable risk factor with a high prevalence among older adults. Exercise is a nonpharmacological treatment shown to benefit all patients with hypertension. This study examined the effects of a 14-week moderate intensity resistance training program (RT) on the maintenance of blood pressure and hand grip strength during an extended detraining period in elderly hypertensive women. Twelve hypertensive sedentary elderly women completed 14 weeks of whole body RT at a moderate perceived exertion following a detraining period of 14 weeks. Following the training period, participants demonstrated an increase in absolute hand grip strength (P=0.001), relative hand grip strength (P=0.032) and a decrease of systolic (P=0.001), diastolic (P=0.008), and mean blood pressure (P=0.002) when compared to pre-exercise values. In addition, these effects were sustained after 14 weeks of detraining. Resistance training may be a valuable method to improve muscular strength and blood pressure in elderly people with benefits being maintained up to 14 weeks following training cessation.

  20. Determination of the relationship between the wrist isokinetic muscle strenght and the grip strength in tennis players aged between 12-14

    Science.gov (United States)

    Akınoğlu, Bihter; Kocahan, Tuğba; Yıldırım, Necmiye Ün; Soylu, Çağlar; Hasanoğlu, Adnan

    2017-01-01

    Aim: The purpose of this study is to determine the relationship between isokinetic wrist muscle strenght and grip strength in tennis players aged between 12-14. Methods: This study was carried out with the participation of 9 (3 female and 6 male) tennis players aged between 12-14 (means 13,22±0,83). Weight, height, body mass index and dominant extremity of the players were recorded. İsokinetic measurement was performed with Isomed 2000® device. İsokinetic testing protocol; before the test all players performed the wrist flexion and extension isokinetic test with the 5 repeating at 90 º/sec as a warm-up and for comprehenting the test. Then, wrist flexion and extension concentric-concentric strength measurements were performed with the 5 repeating at 60 º/sec and with the 15 repeating at 240 º/sec with the angle between 50 degrees of wrist flexion and 60 degrees of wrist extension and peak torque values were recorded. Standard Jamar® Dynamometer was used for grip strength measurements. Grip strenght was performed firstly in sitting position, which is the position of standard measurement. Secondly, in standing position, the elbow was in full ekstansion and the forearm was in neutral position. Thirdly, in standing position the wrist was positioned approximately 30° extension and 10° ulnar deviation. This test was repeated 3 times in all test position and the mean of three scores were recorded. Firstly, the dominant hand, then the non-dominant hand was evoluated. They were allowed to rest for 30 seconds between each grip measurement. Correlation between peak tork of isokinetic muscle strenght and grip strength was done having been used Spearman correlation test. Findings: It was determined that there was a significant positive relation between wrist flexion-extension isokinetic muscle strength and grip strenght in tennis players aged between 12-14. Clinically, grip strength measured in the standard sitting position was found more as compared to the other

  1. G. Dupuytren's contracture: an inaccurate denomination.

    Science.gov (United States)

    Vrebos, J

    2009-10-01

    The question of priority in describing 'Dupuytren's disease' as a result of permanent retraction of the palmar aponeurosis has been debated for a long time. This article tries to identify the pioneers who were involved in the research of the origin of permanent contracture of fingers and palm of the hand, and to find out to whom the priority of this affection should be attributed. Selected passages of several authors, as well as of Dupuytren's writings (mainly in italics and translated into English) are used to try and find the truth concerning the primary description of the disease.

  2. Erratum regarding inaccurate authorship attributions noted.

    Science.gov (United States)

    2017-01-01

    For the paper entitled Pain improvement in rheumatoid arthritis with hyperbaric oxygen: report of three cases,' which appeared in the July-August 2016 issue of UHM (43-4), author attributions read as: John B. Slade MD, Mary V. Potts RN, Alan M. Flower DO, Michelle T. Sit MD, Thomas W. Schmidt MD. Undersea Hyperb Med. 2016 Jul-Aug; 43(4): 467-472. The corrected authorship reads as: John B. Slade MD, Mary V. Potts RN, Alan M. Flower DO, Karen M. Sky, MD, FACP, FACR, Michelle T. Sit MD, Thomas W. Schmidt MD. Undersea Hyperb Med. 2016 Jul-Aug; 43(4): 467-472. Dr. Karen M. Sky was inadvertently deleted from the list of authors. UHM apologizes for the omission.

  3. Gathering asychronous mobile robots with inaccurate compasses

    OpenAIRE

    Souissi, Samia; Defago, Xavier; Yamashita, Masafumi

    2006-01-01

    This paper considers a system of asynchronous autonomous mobile robots that can move freely in a twodimensional plane with no agreement on a common coordinate system. Starting from any initial configuration, the robots are required to eventually gather at a single point, not fixed in advance (gathering problem). Prior work has shown that gathering oblivious (i.e., stateless) robots cannot be achieved deterministically without additional assumptions. In particular, if robots can detect multipl...

  4. Effects of varying the load force range and frequency on force coordination in static manipulation.

    Science.gov (United States)

    Uygur, Mehmet; de Freitas, Paulo B; Jaric, Slobodan

    2010-05-14

    A frequency associated deterioration of the hand grip (GF; normal component of force acting at the digits-object contact area) and load force (LF; the tangential component) coordination has been demonstrated in a variety of repetitive manipulation tasks. However, it remains unknown whether the effect originates from the task frequency per se, or from the rate of LF change (a prediction that could be derived from the minimum jerk hypothesis) which increases with both LF frequency and LF range. The aim of the study was to discern between the effects of LF frequency and LF range (which affects only the rate of LF) in static manipulation tasks. Subjects (N=15) exerted a sinusoidal LF pattern against an externally fixed instrumented handle at 5 different LF frequencies (0.67-3.33Hz) and ranges (6-30N). The results revealed weak and mainly non-significant effects of both LF range and frequency on GF scaling (GF/LF ratio). However, both GF-LF coupling (assessed by correlation coefficients) and GF modulation (change in GF relative to LF variation) demonstrated a prominent decrease associated with LF frequency, but not with LF range. The observed findings were interpreted by switching between hypothetical synergies of GF and LF producing muscles separately employed in the phases of the increasing and decreasing forces. From the practical aspect, however, the results suggest that the frequency, but not the LF range should be taken into account when designing rhythmic manipulation tasks, developing standard tests of hand function based on GF-LF coordination, or comparing the data from different studies. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

  5. Muscle strength assessment in critically ill patients with handheld dynamometry: an investigation of reliability, minimal detectable change, and time to peak force generation.

    Science.gov (United States)

    Baldwin, Claire E; Paratz, Jennifer D; Bersten, Andrew D

    2013-02-01

    Dynamometry is an objective tool for volitional strength evaluation that may overcome the limited sensitivity of the Medical Research Council scale for manual muscle tests, particularly at grades 4 and 5. The primary aims of this study were to investigate the reliability, minimal detectable change, and time to peak muscle force, measured with portable dynamometry, in critically ill patients. Isometric hand grip, elbow flexion, and knee extension were measured with portable dynamometry. Interrater consistency (intraclass correlation coefficient [95% confidence interval]) (0.782 [0.321-0.930] to 0.946 [0.840-0.982]) and test-retest agreement (0.819 [0.390-0.943] to 0.918 [0.779-0.970]) were acceptable for all dynamometry forces, with the exception of left elbow flexion. Despite generally good reliability, a mean change (upper 95% confidence interval) of 2.8 (7.8) kg, 1.9 (5.2) kg, and 2.6 (7.1) kg may be required from a patient's baseline force measurement of right grip, elbow flexion, and knee extension to reflect real force changes. There was also a delay in the time for critically ill patients to generate peak muscle forces, compared with healthy controls (P ≤ .001). Dynamometry can provide reliable measurements in alert critically ill patients, but moderate changes in strength may be required to overcome measurement error, during the acute recovery period. Deficits in force timing may reflect impaired neuromuscular control. Copyright © 2013 Elsevier Inc. All rights reserved.

  6. Correlation of force control with regional spinal DTI in patients with cervical spondylosis without signs of spinal cord injury on conventional MRI

    International Nuclear Information System (INIS)

    Lindberg, Paavel G.; Sanchez, Katherine; Rannou, Francois; Poiraudeau, Serge; Ozcan, Fidan; Feydy, Antoine; Maier, Marc A.

    2016-01-01

    The aim of this study was to investigate spinal cord structure in patients with cervical spondylosis where conventional MRI fails to reveal spinal cord damage. We performed a cross-sectional study of patients with cervical spondylosis without conventional MRI findings of spinal cord damage and healthy controls. Subjects were studied using spinal diffusion tensor imaging (DTI), precision grip and foot force-tracking tasks, and a clinical examination including assessment of neurological signs. A regional analysis of lateral and medial spinal white matter across multiple cervical levels (C1-C5) was performed. DTI revealed reduced fractional anisotropy (FA) and increased radial diffusivity (RD) in the lateral spinal cord at the level of greatest compression (lowest Pavlov ratio) in patients (p < 0.05). Patients with spondylosis had greater error and longer release duration in both grip and foot force-tracking. Similar spinal cord deficits were present in patients without neurological signs. Increased error in grip and foot tracking (low accuracy) correlated with increased RD in the lateral spinal cord at the level of greatest compression (p ≤ 0.01). Spinal DTI can detect subtle spinal cord damage of functional relevance in cervical spondylosis, even in patients without signs on conventional T2-imaging and without neurological signs. (orig.)

  7. Correlation of force control with regional spinal DTI in patients with cervical spondylosis without signs of spinal cord injury on conventional MRI

    Energy Technology Data Exchange (ETDEWEB)

    Lindberg, Paavel G. [Universite Paris Descartes, Sorbonne Paris Cite, FR 3636 Neurosciences, Paris (France); Centre de Psychiatrie et Neurosciences, Inserm U894, Paris (France); Universite Paris Descartes, Sorbonne Paris Cite, Paris (France); Universite Paris Descartes, Service de Radiologie B, APHP, CHU Cochin, Faculte de Medecine, Paris (France); Sanchez, Katherine; Rannou, Francois; Poiraudeau, Serge [Universite Paris Descartes, Sorbonne Paris Cite, Paris (France); Service de Medecine Physique et de Readaptation, APHP, CHU Cochin, Paris (France); INSERM U1153 Epidemiologie Clinique des Maladies Osteo-Articulaires, Paris (France); Ozcan, Fidan [Universite Paris Descartes, Sorbonne Paris Cite, FR 3636 Neurosciences, Paris (France); Feydy, Antoine [Universite Paris Descartes, Sorbonne Paris Cite, FR 3636 Neurosciences, Paris (France); Universite Paris Descartes, Sorbonne Paris Cite, Paris (France); Universite Paris Descartes, Service de Radiologie B, APHP, CHU Cochin, Faculte de Medecine, Paris (France); Maier, Marc A. [Universite Paris Descartes, Sorbonne Paris Cite, FR 3636 Neurosciences, Paris (France); Universite Paris Descartes, Sorbonne Paris Cite, Paris (France); Universite Paris Diderot, Sorbonne Paris Cite, Paris (France)

    2016-03-15

    The aim of this study was to investigate spinal cord structure in patients with cervical spondylosis where conventional MRI fails to reveal spinal cord damage. We performed a cross-sectional study of patients with cervical spondylosis without conventional MRI findings of spinal cord damage and healthy controls. Subjects were studied using spinal diffusion tensor imaging (DTI), precision grip and foot force-tracking tasks, and a clinical examination including assessment of neurological signs. A regional analysis of lateral and medial spinal white matter across multiple cervical levels (C1-C5) was performed. DTI revealed reduced fractional anisotropy (FA) and increased radial diffusivity (RD) in the lateral spinal cord at the level of greatest compression (lowest Pavlov ratio) in patients (p < 0.05). Patients with spondylosis had greater error and longer release duration in both grip and foot force-tracking. Similar spinal cord deficits were present in patients without neurological signs. Increased error in grip and foot tracking (low accuracy) correlated with increased RD in the lateral spinal cord at the level of greatest compression (p ≤ 0.01). Spinal DTI can detect subtle spinal cord damage of functional relevance in cervical spondylosis, even in patients without signs on conventional T2-imaging and without neurological signs. (orig.)

  8. Age-dependent changes in the neural correlates of force modulation: an fMRI study.

    Science.gov (United States)

    Ward, Nick S; Swayne, Orlando B C; Newton, Jennifer M

    2008-09-01

    Functional imaging studies in humans have demonstrated widespread age-related changes in cortical motor networks. However, the relative contribution of cortical regions during motor performance varies not only with age but with task parameters. In this study, we investigated whether motor system activity during a task involving increasingly forceful hand grips was influenced by age. Forty right-handed volunteers underwent functional magnetic brain imaging whilst performing repetitive isometric hand grips with either hand in separate sessions. We found no age-related changes in the average size and shape of the task-related blood oxygen level dependent (BOLD) signal in contralateral primary motor cortex (M1), but did observe reduced ipsilateral M1 deactivation in older subjects (both hands). Furthermore, task-related activity co-varied positively with force output in a number of brain regions, but was less prominent with advancing age in contralateral M1, cingulate sulcus (both hands), sensory and premotor cortices (right hand). These results indicate that a reduced ability to modulate activity in appropriate motor networks when required may contribute to age-related decline in motor performance.

  9. Interfacial force measurements using atomic force microscopy

    NARCIS (Netherlands)

    Chu, L.

    2018-01-01

    Atomic Force Microscopy (AFM) can not only image the topography of surfaces at atomic resolution, but can also measure accurately the different interaction forces, like repulsive, adhesive and lateral existing between an AFM tip and the sample surface. Based on AFM, various extended techniques have

  10. Comparison of hand grip strength and upper limb pressure pain threshold between older adults with or without non-specific shoulder pain

    Directory of Open Access Journals (Sweden)

    Cesar Calvo Lobo

    2017-02-01

    Full Text Available Background There is a high prevalence of non-specific shoulder pain associated with upper limb functional limitations in older adults. The purpose of this study was to determine the minimal clinically important differences (MCID of grip strength and pressure pain threshold (PPT in the upper limb between older adults with or without non-specific shoulder pain. Methods A case-control study was carried out following the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE criteria. A sample of 132 shoulders (mean ± SD years with (n = 66; 76.04 ± 7.58 and without (n = 66; 75.05 ± 6.26 non-specific pain were recruited. The grip strength and PPT of the anterior deltoid and extensor carpi radialis brevis (ECRB muscles were assessed. Results There were statistically significant differences (mean ± SD; P-value for anterior deltoid PPT (2.51 ± 0.69 vs 3.68 ± 0.65, kg/cm2; P < .001, ECRB PPT (2.20 ± 0.60 vs 3.35 ± 0.38 kg/cm2; P < .001 and grip strength (20.78 ± 10.94 vs 24.63 ± 9.38 kg; P = .032 between shoulders with and without non-specific pain, respectively. Discussion The MCID of 1.17 kg/cm2, 1.15 kg/cm2 and 3.84 kg were proposed for anterior deltoid PPT, ECRB PPT and grip strength, respectively, to assess the upper limb of older adults with non-specific shoulder pain after treatment. In addition, univariate and multivariate (linear regression and regression trees analyses may be used to consider age distribution, sex, pain intensity, grip strength and PPT in older adults including clinical and epidemiological studies with non-specific shoulder pain.

  11. Hand-grip strength among older adults in Singapore: a comparison with international norms and associative factors.

    Science.gov (United States)

    Ong, Hui Lin; Abdin, Edimansyah; Chua, Boon Yiang; Zhang, Yunjue; Seow, Esmond; Vaingankar, Janhavi Ajit; Chong, Siow Ann; Subramaniam, Mythily

    2017-08-04

    Hand-grip strength (HGS) serves as a proxy measure for muscle function and physical health. Studies have shown that low HGS is associated with common age-related disorders including frailty and sarcopenia. The aim of the present study was to establish the normative values of HGS among older adults in Singapore and to compare it with data from Western and other Asian countries. The study also aimed to explore the sociodemographic and anthropometric correlates of HGS. Data were collected from 2043 men and women aged 60 years and above who took part in the Well-being of the Singapore Elderly study in 2013. HGS was obtained using a Jamar Plus + digital hand dynamometer. Normative data were stratified by; 5-year age groups, sex and ethnicity. Relationships between the HGS with various sociodemographic and anthropometric correlates were examined using multiple linear regression analysis. The mean HGS demonstrate a decreasing trend with increased age across all ethnic groups and sexes. HGS among Singapore older adults were relatively low compared to Western and other Asian countries. Males in the youngest age group (60-64) and of Chinese ethnicity attained greater HGS values than their counterparts. When the regression analysis was stratified for sex, significant associations were found between height, upper arm circumference with HGS in the males sample, and between height, weight, waist circumference and HGS in the females sample. Older adults in Singapore have a relatively weak HGS compared to other countries. Greater height and weight, and smaller waist circumference are independently associated with greater HGS in females but not males. These results facilitate the interpretation of HGS conducting using Jamar digital-type dynamometers among the older adults in Singapore.

  12. Correlation of fingertip shear force direction with somatosensory cortical activity in monkey

    Science.gov (United States)

    Fortier-Poisson, Pascal; Langlais, Jean-Sébastien

    2015-01-01

    To examine the activity of somatosensory cortex (S1) neurons to self-generated shear forces on the index and thumb, two monkeys were trained to grasp a stationary metal tab with a key grip and exert forces without the fingers slipping in one of four orthogonal directions for 1 s. A majority (∼85%) of slowly adapting and rapidly adapting (RA) S1 neurons had activity modulated with shear force direction. The cells were recorded mainly in areas 1 and 2 of the S1, although some area 3b neurons also responded to shear direction or magnitude. The preferred shear vectors were distributed in every direction, with tuning arcs varying from 50° to 170°. Some RA neurons sensitive to dynamic shear force direction also responded to static shear force but within a narrower range, suggesting that the direction of the shear force may influence the adaptation rate. Other neurons were modulated with shear forces in diametrically opposite directions. The directional sensitivity of S1 cortical neurons is consistent with recordings from cutaneous afferents showing that shear direction, even without slip, is a powerful stimulus to S1 neurons. PMID:26467520

  13. Association between dietary protein intake and grip strength among adults aged 51 years and over: What We Eat in America, National Health and Nutrition Examination Survey 2011-2014.

    Directory of Open Access Journals (Sweden)

    Suruchi Mishra

    Full Text Available Distributing daily protein intake evenly across meals (∼25-30g/meal has been suggested to improve muscle mass. The aim of this research is to examine the association between grip strength, total protein intake and its distribution across day's meals in older adults.Nationally representative dietary intake data of adults aged 51 years and older (n = 4,123 who participated in What We Eat in America, NHANES 2011-2014 were analyzed. Protein intake per day and per eating occasion (breakfast, lunch, dinner, and snack were determined. Combined grip strength was calculated and expressed in kilograms. Grip strength of individuals consuming ≥25g protein at 1 eating occasion was compared with those consuming same level of protein at 2 and 3 or more eating occasions. Grip strength of individuals in quartile 1 of daily protein intake was compared to those in the other quartiles. All associations were examined without and with adjustment for age, race/ethnicity, physical activity, health status, and smoking status. The comparison involving eating occasions and protein intake quartiles were further adjusted for daily protein intake and energy intake, respectively.Only 33% of men and 19% of women had protein intake of ≥25g at 2 or more eating occasions. These individuals also had higher grip strength and daily protein intake. Grip strength was positively associated with consumption of ≥25g protein at 2 eating occasions as compared to consumption of same level of protein at 1 eating occasion (p<0.05 in unadjusted model, but not when adjusted. Grip strength was positively associated with daily protein intake among women in quartiles 3 and 4 (p<0.05 of protein intake in both unadjusted and adjusted models compared to lowest protein intake. Among men, grip strength was associated with daily protein intake in quartiles 3 and 4 (p<0.05 in the unadjusted model, but not when adjusted.In a nationally representative sample of older adults, consuming ≥25g

  14. Labor Force Participation Rate

    Data.gov (United States)

    City and County of Durham, North Carolina — This thematic map presents the labor force participation rate of working-age people in the United States in 2010. The 2010 Labor Force Participation Rate shows the...

  15. Aerodynamic Lifting Force.

    Science.gov (United States)

    Weltner, Klaus

    1990-01-01

    Describes some experiments showing both qualitatively and quantitatively that aerodynamic lift is a reaction force. Demonstrates reaction forces caused by the acceleration of an airstream and the deflection of an airstream. Provides pictures of demonstration apparatus and mathematical expressions. (YP)

  16. Acoustic force spectroscopy

    NARCIS (Netherlands)

    Sitters, G.; Kamsma, D.; Thalhammer, G.; Ritsch-Marte, M.; Peterman, E.J.G.; Wuite, G.J.L.

    2015-01-01

    Force spectroscopy has become an indispensable tool to unravel the structural and mechanochemical properties of biomolecules. Here we extend the force spectroscopy toolbox with an acoustic manipulation device that can exert forces from subpiconewtons to hundreds of piconewtons on thousands of

  17. Forces in General Relativity

    Science.gov (United States)

    Ridgely, Charles T.

    2010-01-01

    Many textbooks dealing with general relativity do not demonstrate the derivation of forces in enough detail. The analyses presented herein demonstrate straightforward methods for computing forces by way of general relativity. Covariant divergence of the stress-energy-momentum tensor is used to derive a general expression of the force experienced…

  18. Statistics of force networks

    Science.gov (United States)

    Tighe, Brian

    2009-03-01

    We study the statistics of contact forces in the force network ensemble, a minimal model of jammed granular media that emphasizes the role of vector force balance. We show that the force probability distribution can be calculated analytically by way of an analogy to equilibrium ensemble methods. In two dimensions the large force tail decays asymptotically as a Gaussian, distinct from earlier predictions, due to the existence of a conserved quantity related to the presence of local vector force balance. We confirm our predictions with highly accurate statistical sampling -- we sample the force distribution over more than 40 decades -- permitting unambiguous confrontation of theory with numerics. We show how the conserved quantity arises naturally within the context of any constant stress ensemble.

  19. Quantum fictitious forces

    DEFF Research Database (Denmark)

    Bialynicki-Birula, I; Cirone, M.A.; Dahl, Jens Peder

    2002-01-01

    We present Heisenberg's equation of motion for the radial variable of a free non-relativistic particle in D dimensions. The resulting radial force consists of three contributions: (i) the quantum fictitious force which is either attractive or repulsive depending on the number of dimensions, (ii......) a singular quantum force located at the origin, and (iii) the centrifugal force associated with non-vanishing angular momentum. Moreover, we use Heisenberg's uncertainty relation to introduce a lower bound for the kinetic energy of an ensemble of neutral particles. This bound is quadratic in the number...... of atoms and can be traced back to the repulsive quantum fictitious potential. All three forces arise for a free particle: "Force without force"....

  20. Malaria's deadly grip

    DEFF Research Database (Denmark)

    Smith, Joseph D; Rowe, J Alexandra; Higgins, Matthew K

    2013-01-01

    Cytoadhesion of Plasmodium falciparum-infected erythrocytes to host microvasculature is a key virulence determinant. Parasite binding is mediated by a large family of clonally variant adhesion proteins, termed P. falciparum erythrocyte membrane protein 1 (PfEMP1), encoded by var genes and expressed...

  1. Enter the Gripping Beast

    DEFF Research Database (Denmark)

    Sindbæk, Søren Michael

    2012-01-01

    Innovations in culture or technology are moments, which offer extraordinary insights into the working of societies. The ways in which new practices or things are adopted by groups or individuals, or encounter resistance or rejection from the same, trace a section through the social topography...

  2. Hand grip strength

    DEFF Research Database (Denmark)

    Frederiksen, Henrik; Gaist, David; Petersen, Hans Christian

    2002-01-01

    to be associated with muscular functioning in other muscle groups and with activities of daily living (ADL) functioning, and it predicts incident disability. We studied 1,757 Danish twin pairs aged 45-96 years, and found that this phenotype has a heritability of 52% (95% confidence interval (CI), 48-55...

  3. Effect of cervical vs. thoracic spinal manipulation on peripheral neural features and grip strength in subjects with chronic mechanical neck pain: a randomized controlled trial.

    Science.gov (United States)

    Bautista-Aguirre, Francisco; Oliva-Pascual-Vaca, Ángel; Heredia-Rizo, Alberto M; Boscá-Gandía, Juan J; Ricard, François; Rodriguez-Blanco, Cleofás

    2017-06-01

    Cervical and thoracic spinal manipulative therapy has shown positive impact for relief of pain and improve function in non-specific mechanical neck pain. Several attempts have been made to compare their effectiveness although previous studies lacked a control group, assessed acute neck pain or combined thrust and non-thrust techniques. To compare the immediate effects of cervical and thoracic spinal thrust manipulations on mechanosensitivity of upper limb nerve trunks and grip strength in patients with chronic non-specific mechanical neck pain. Randomized, single-blinded, controlled clinical trial. Private physiotherapy clinical consultancy. Eighty-eight subjects (32.09±6.05 years; 72.7% females) suffering neck pain (grades I or II) of at least 12 weeks of duration. Participants were distributed into three groups: 1) cervical group (N.=28); 2) thoracic group (N.=30); and 3) control group (N.=30). One treatment session consisting of applying a high-velocity low-amplitude spinal thrust technique over the lower cervical spine (C7) or the upper thoracic spine (T3) was performed, while the control group received a sham-manual contact. Measurements were taken at baseline and after intervention of the pressure pain threshold over the median, ulnar and radial nerves. Secondary measures included assessing free-pain grip strength with a hydraulic dynamometer. No statistically significant differences were observed when comparing between-groups in any of the outcome measures (P>0.05). Those who received thrust techniques, regardless of the manipulated area, reported an immediate increase in mechanosensitivity over the radial (both sides) and left ulnar nerve trunks (Pneck pain. A single treatment session using cervical or thoracic thrust techniques is not enough to achieve clinically relevant changes on neural mechanosensitivity and grip strength in chronic non-specific mechanical neck pain.

  4. Anatomical variations of the deep head of Cruveilhier of the flexor pollicis brevis and its significance for the evolution of the precision grip.

    Science.gov (United States)

    Dunlap, Samuel S; Aziz, M Ashraf; Ziermann, Janine M

    2017-01-01

    Cruveilhier described in 1834 the human flexor pollicis brevis (FPB), a muscle of the thenar compartment, as having a superficial and a deep head, respectively, inserted onto the radial and ulnar sesamoids of the thumb. Since then, Cruveilhier's deep head has been controversially discussed. Often this deep head is confused with Henle's "interosseous palmaris volaris" or said to be a slip of the oblique adductor pollicis. In the 1960s, Day and Napier described anatomical variations of the insertions of Cruveilhier's deep head, including its absence, and hypothesized, that the shift of the deep head's insertion from ulnar to radial facilitated "true opposability" in anthropoids. Their general thesis for muscular arrangements underlying the power and precision grip is sound, but they did not delineate their deep head from Henle's muscle or the adductor pollicis, and their description of the attachments of Cruveilhier's deep head were too vague and not supported by a significant portion of the anatomical literature. Here, we reinvestigated Cruveilhier's deep head to resolve the controversy about it and because many newer anatomy textbooks do not describe this muscle, while it is often an obvious functionally (writing, texting, precision grip) and clinically significant thenar muscle. For the first time, we empirically delineated Cruveilhier's deep head from neighboring muscles with which it was previously confused. We observed 100% occurrence of the uncontested deep head in 80 human hands, displaying a similar variability of insertions as Day and Napier, but in significantly different numbers. Furthermore, we found variability in the origin and included as important landmarks the trapezoid and the ligamentum carpi radiatum. We tested the assertion regarding the evolutionary morphology and its role in the improvements in thumb movements during various precision grips. Our overall conclusions differ with respect to the developmental and evolutionary origin of the FPB

  5. The Effect of Hand Dimensions, Hand Shape and Some Anthropometric Characteristics on Handgrip Strength in Male Grip Athletes and Non-Athletes

    Science.gov (United States)

    Fallahi, Ali Asghar; Jadidian, Ali Akbar

    2011-01-01

    It has been suggested that athletes with longer fingers and larger hand surfaces enjoy stronger grip power. Therefore, some researchers have examined a number of factors and anthropometric variables that explain this issue. To our knowledge, the data is scarce. Thus, the aim of this study was to investigate the effect of hand dimensions, hand shape and some anthropometric characteristics on handgrip strength in male grip athletes and non-athletes. 80 subjects aged between 19 and 29 participated in this study in two groups including: national and collegian grip athletes (n=40), and non-athletes (n=40). Body height and mass were measured to calculate body mass index. The shape of the dominant hand was drawn on a piece of paper with a thin marker so that finger spans, finger lengths, and perimeters of the hand could be measured. The hand shape was estimated as the ratio of the hand width to hand length. Handgrip strength was measured in the dominant and non-dominant hand using a standard dynamometer. Descriptive statistics were used for each variable and independent t test was used to analyze the differences between the two groups. The Pearson correlation coefficient test was used to evaluate the correlation between studied variables. Also, to predict important variables in handgrip strength, the linear trend was assessed using a linear regression analysis. There was a significant difference between the two groups in absolute handgrip strength (p0.05) were significantly different between the groups (ptalent identification in handgrip-related sports and in clinical settings as well. PMID:23486361

  6. Low Normalized Grip Strength is a Biomarker for Cardiometabolic Disease and Physical Disabilities Among U.S. and Chinese Adults.

    Science.gov (United States)

    Peterson, Mark D; Duchowny, Kate; Meng, Qinqin; Wang, Yafeng; Chen, Xinxin; Zhao, Yaohui

    2017-10-12

    Evidence highlights the importance of muscular strength as a protective factor for health and function across aging populations. The purpose of this study was to examine the extent to which low normalized grip strength (NGS) serves as a biomarker for both cardiometabolic disease and physical disability in U.S. and Chinese adults. Middle aged and older adults from the U.S. National Health and Nutrition Examination Survey 2011-2012 and 2013-2014 combined surveys (n = 4,544), and the 2011 wave of the China Health and Retirement Longitudinal Study (n = 6,030) were included. Strength was assessed using a handgrip dynamometer, and was normalized to body mass. Weighted logistic regression models were used to assess the association between NGS and diabetes, hyperglycemia, hypertriglyceridemia, low HDL-cholesterol, hypertension, and physical disability status, while controlling for age, sex, and sociodemographic characteristics. Every 0.05 lower NGS was independently associated with a 1.49 (95% confidence interval [CI]: 1.42-1.56) and 1.17 (95% CI: 1.11-1.23) odds for diabetes; a 1.46 (95% CI: 1.39-1.53) and 1.11 (95% CI: 1.07-1.15) odds of hyperglycemia; a 1.15 (95% CI: 1.07-1.25) and 1.11 (95% CI: 1.08-1.14) odds of hypertriglyceridemia; a 1.22 (95% CI: 1.17-1.27) and 1.15 (95% CI: 1.12-1.18) odds of low HDL-cholesterol; a 1.19 (95% CI: 1.14-1.24) and 1.10 (95% CI: 1.07-1.14) odds of hypertension; and a 1.36 (95% CI: 1.29-1.42) and 1.10 (95% CI: 1.05-1.15) odds for physical disability status in U.S. and Chinese adults, respectively. NGS was robustly associated with both cardiometabolic disease risk and physical disabilities in U.S. and Chinese aging adults. © The Author 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  7. Evaluating the flux of extraterrestrial osmium at the onset of Younger Dryas in the GRIP ice core

    Science.gov (United States)

    Seo, J. H.; Han, C.; Hong, S.; Steffensen, J. P.; Sharma, M.

    2016-12-01

    The Younger Dryas (YD: 12.9-11.6 ka) was an abrupt cooling event during the last deglaciation. The mechanism behind the cooling is suggested to be a temporary slowdown of North Atlantic thermohaline circulation due to catastrophic release of meltwater from proglacial Lake Agassiz during the retreat of the Laurentide Ice Sheet [1]. An alternative hypothesis states that the cooling was directly/indirectly triggered by one or more cosmic airbursts/impacts [2]. While several papers have documented evidence for a YD extraterrestrial impact including microspherules, nanodiamonds, magnetic grains, and glass-like carbon [4-7], this hypothesis remains controversial [8-10]. In a recent study by Petaev et al. [11], an unusually high Pt/Ir ratio of 1200 was discovered in the GISP-2 ice core at the onset of YD, indicating a large Pt enriched iron meteorite impact. Such a high Pt/Ir in extraterrestrial materials has not been documented [12]. Thus, Petaev et al. [11] acknowledge that the interpretation of the Pt anomaly is based on circumstantial evidence. The distinct Os isotopic composition (187Os/188Os ratio) of the terrestrial (=1.26) and extraterrestrial (= 0.13) sources should allow us to evaluate if there was a meteorite impact at the YD boundary. These analyses are technically challenging owing to rather low concentration of Os in ice-melts ( 1x10-15g/g). Here, we will present Os isotope data from the GRIP ice core spanning the time period through YD to shed light on the meteorite/comet impact hypothesis. [1] Broecker et al. (1989) Nature 341, 318-321; [2] Firestone et al. (2007) PNAS. 104, 16016-16021; [3] Bunch et al. (2012) PNAS. 109, 1903-1912; [4] LeCompte et al. (2012) PNAS. 109, 2960-2969; [5] Wittke et al. (2013) PNAS 110, 2088-2097; [6] Wu et al. (2013) PNAS. 110, 3557-3566; [7] Kennett et al. (2015) PNAS 112, E4344-E4353; [8] Pinter et al. (2011) Earth Sci. Rev., 106, 247-264; [9] Holliday et al. (2014) J. Quat. Sci. 29, 515-530; [10] Meltzer et al. (2014) PNAS

  8. Relativistic Linear Restoring Force

    Science.gov (United States)

    Clark, D.; Franklin, J.; Mann, N.

    2012-01-01

    We consider two different forms for a relativistic version of a linear restoring force. The pair comes from taking Hooke's law to be the force appearing on the right-hand side of the relativistic expressions: d"p"/d"t" or d"p"/d["tau"]. Either formulation recovers Hooke's law in the non-relativistic limit. In addition to these two forces, we…

  9. Selective use of visual information signaling objects' center of mass for anticipatory control of manipulative fingertip forces.

    Science.gov (United States)

    Salimi, Iran; Frazier, Wendy; Reilmann, Ralf; Gordon, Andrew M

    2003-05-01

    The present study examines whether visual information indicating the center of mass (CM) of an object can be used for the appropriate scaling of fingertip forces at each digit during precision grip. In separate experiments subjects lifted an object with various types of visual cues concerning the CM location several times and then rotated and lifted it again to determine whether the visual cues signaling the new location of the CM could be used to appropriately scale the fingertip forces. Specifically, subjects had either no visual cues, visual instructional cues (i.e., an indicator) or visual geometric cues where the longer axis of the object indicated the CM. When no visual cues were provided, subjects were unable to appropriately scale the load forces at each digit following rotation despite their knowledge of the new weight distribution. When visual cues regarding the CM location were provided, the nature of the visual cues determined their effectiveness in retrieval of internal representations underlying the anticipatory scaling of fingertip forces. Specifically, when subjects were provided with visual instructional information, they were unable to appropriately scale the forces. More appropriate scaling of the load forces occurred when the visual cues were ecologically meaningful, i.e., when the shape of the object indicated the CM location. We suggest that visual instructional cues do not have access to the implicit processes underlying dynamic force control, whereas visual geometric cues can be used for the retrieval of the internal representation related to CM for appropriate partitioning of the forces in each digit.

  10. RSOI: Force Deployment Bottleneck

    National Research Council Canada - National Science Library

    D'Amato, Mark

    1998-01-01

    This study uses The Theory Of Constraints (TOC) management methodology and recent military missions to show that RSOI operations are generally the limiting constraint to force deployment operations...

  11. Bi-Force

    DEFF Research Database (Denmark)

    Sun, Peng; Speicher, Nora K; Röttger, Richard

    2014-01-01

    outperformed existing tools with Bi-Force at least when following the evaluation protocols from Eren et al. Bi-Force is implemented in Java and integrated into the open source software package of BiCluE. The software as well as all used datasets are publicly available at http://biclue.mpi-inf.mpg.de....... of pairwise similarities. We first evaluated the power of Bi-Force to solve dedicated bicluster editing problems by comparing Bi-Force with two existing algorithms in the BiCluE software package. We then followed a biclustering evaluation protocol in a recent review paper from Eren et al. (2013) (A...

  12. Intermolecular and surface forces

    CERN Document Server

    Israelachvili, Jacob N

    2011-01-01

    This reference describes the role of various intermolecular and interparticle forces in determining the properties of simple systems such as gases, liquids and solids, with a special focus on more complex colloidal, polymeric and biological systems. The book provides a thorough foundation in theories and concepts of intermolecular forces, allowing researchers and students to recognize which forces are important in any particular system, as well as how to control these forces. This third edition is expanded into three sections and contains five new chapters over the previous edition.· starts fr

  13. Macroscopic forces from supersymmetry

    CERN Document Server

    Dimopoulos, Savas K

    1996-01-01

    We argue that theories in which supersymmetry breaking originates at low energies often contain scalar particles that mediate coherent gravitational strength forces at distances less than a cm. We estimate the strength and range of these forces in several cases. Present limits on such forces are inadequate. However new techniques, such as those based on small cryogenic mechanical oscillators, may improve the present limits by ten orders of magnitude or discover new forces as weak as 1 \\% of gravity at distances down to 40 microns.

  14. Understanding end-of-life caring practices in the emergency department: developing Merleau-Ponty's notions of intentional arc and maximum grip through praxis and phronesis.

    Science.gov (United States)

    Chan, Garrett K

    2005-01-01

    The emergency department (ED) is a fast-paced, highly stressful environment where clinicians function with little or suboptimal information and where time is measured in minutes and hours. In addition, death and dying are phenomena that are often experienced in the ED. Current end-of-life care models, based on chronic illness trajectories, may be difficult to apply in the ED. A philosophical approach examining end-of-life care may help us understand how core medical and nursing values are embodied as care practices and as ethical comportment. The integration of Aristotle's notions of phronesis and praxis with Merleau-Ponty's ontological notions of intentional arc and maximum grip in the context of the culture and practices of the ED offers a unique view of clinical and ethical practice at the end-of-life in the emergency setting. Caring for people at the end-of-life calls us to act virtuously based on previous experience, meanings and local practices. The maximum grip of the ultimate particulars of the situation combined with one's experiential and theoretical knowledge opens up situated possibilities for the expert clinician.

  15. Study on real-time force feedback for a master-slave interventional surgical robotic system.

    Science.gov (United States)

    Guo, Shuxiang; Wang, Yuan; Xiao, Nan; Li, Youxiang; Jiang, Yuhua

    2018-04-13

    In robot-assisted catheterization, haptic feedback is important, but is currently lacking. In addition, conventional interventional surgical robotic systems typically employ a master-slave architecture with an open-loop force feedback, which results in inaccurate control. We develop herein a novel real-time master-slave (RTMS) interventional surgical robotic system with a closed-loop force feedback that allows a surgeon to sense the true force during remote operation, provide adequate haptic feedback, and improve control accuracy in robot-assisted catheterization. As part of this system, we also design a unique master control handle that measures the true force felt by a surgeon, providing the basis for the closed-loop control of the entire system. We use theoretical and empirical methods to demonstrate that the proposed RTMS system provides a surgeon (using the master control handle) with a more accurate and realistic force sensation, which subsequently improves the precision of the master-slave manipulation. The experimental results show a substantial increase in the control accuracy of the force feedback and an increase in operational efficiency during surgery.

  16. Two-dimensional static manipulation tasks: does force coordination depend on change of the tangential force direction?

    Science.gov (United States)

    Uygur, Mehmet; Jin, Xin; Knezevic, Olivera; Jaric, Slobodan

    2012-10-01

    Coordination of the grip force (GF) with a tangential force (TF, often referred to as load force) exerted along a certain line in space (i.e., one-dimensional tasks) during object manipulation has proved both to be high and based on feed-forward neural control mechanisms. However, GF-TF coordination deteriorates when the TF of one-dimensional task consecutively switches its direction (bidirectional task). In the present study, we aimed to explore GF-TF coordination in the generally neglected multi-dimensional manipulations. We hypothesized that the coordination would depend on the number of unidirectional and bidirectional orthogonal components of a two-dimensional TF exertion. Fourteen subjects traced various circular TF patterns and their orthogonal diameters shown on a computer screen by exerting a static TF. As expected, the unidirectional tasks revealed higher GF-TF coordination than the bidirectional ones (e.g., higher GF-TF correlations and GF gains, and lower GF/TF ratio). Regarding the circular tasks, most of the data were in line with the hypothesis revealing higher coordination associated with higher number of unidirectional components. Of particular importance could be that the circular tasks also revealed prominent time lags of GF with respect to TF, suggesting involvement of feedback mechanisms. We conclude that the force coordination in bidirectional static manipulations could be affected by changes in TF direction along either of its orthogonal components. The time lags observed from the circular tasks could be a consequence of the activity of sensory afferents, rather than of the visual feedback provided or the task complexity.

  17. Climate forcings and feedbacks

    Science.gov (United States)

    Hansen, James

    1993-01-01

    Global temperature has increased significantly during the past century. Understanding the causes of observed global temperature change is impossible in the absence of adequate monitoring of changes in global climate forcings and radiative feedbacks. Climate forcings are changes imposed on the planet's energy balance, such as change of incoming sunlight or a human-induced change of surface properties due to deforestation. Radiative feedbacks are radiative changes induced by climate change, such as alteration of cloud properties or the extent of sea ice. Monitoring of global climate forcings and feedbacks, if sufficiently precise and long-term, can provide a very strong constraint on interpretation of observed temperature change. Such monitoring is essential to eliminate uncertainties about the relative importance of various climate change mechanisms including tropospheric sulfate aerosols from burning of coal and oil smoke from slash and burn agriculture, changes of solar irradiance changes of several greenhouse gases, and many other mechanisms. The considerable variability of observed temperature, together with evidence that a substantial portion of this variability is unforced indicates that observations of climate forcings and feedbacks must be continued for decades. Since the climate system responds to the time integral of the forcing, a further requirement is that the observations be carried out continuously. However, precise observations of forcings and feedbacks will also be able to provide valuable conclusions on shorter time scales. For example, knowledge of the climate forcing by increasing CFC's relative to the forcing by changing ozone is important to policymakers, as is information on the forcing by CO2 relative to the forcing by sulfate aerosols. It will also be possible to obtain valuable tests of climate models on short time scales, if there is precise monitoring of all forcings and feedbacks during and after events such as a large volcanic eruption

  18. Elementary Particles and Forces.

    Science.gov (United States)

    Quigg, Chris

    1985-01-01

    Discusses subatomic particles (quarks, leptons, and others) revealed by higher accelerator energies. A connection between forces at this subatomic level has been established, and prospects are good for a description of forces that encompass binding atomic nuclei. Colors, fundamental interactions, screening, camouflage, electroweak symmetry, and…

  19. The forces in Nature

    CERN Multimedia

    CERN AC

    1998-01-01

    The different forces, together with a pictorial analogy of how the exchange of particles works. The table lists the relative strength of the couplings, the quanta associated with the force fields and the bodies of phenomena in which they have a dominant role.

  20. Forces in yeast flocculation

    Science.gov (United States)

    El-Kirat-Chatel, Sofiane; Beaussart, Audrey; Vincent, Stéphane P.; Abellán Flos, Marta; Hols, Pascal; Lipke, Peter N.; Dufrêne, Yves F.

    2015-01-01

    In the baker's yeast Saccharomyces cerevisiae, cell-cell adhesion (``flocculation'') is conferred by a family of lectin-like proteins known as the flocculin (Flo) proteins. Knowledge of the adhesive and mechanical properties of flocculins is important for understanding the mechanisms of yeast adhesion, and may help controlling yeast behaviour in biotechnology. We use single-molecule and single-cell atomic force microscopy (AFM) to explore the nanoscale forces engaged in yeast flocculation, focusing on the role of Flo1 as a prototype of flocculins. Using AFM tips labelled with mannose, we detect single flocculins on Flo1-expressing cells, showing they are widely exposed on the cell surface. When subjected to force, individual Flo1 proteins display two distinct force responses, i.e. weak lectin binding forces and strong unfolding forces reflecting the force-induced extension of hydrophobic tandem repeats. We demonstrate that cell-cell adhesion bonds also involve multiple weak lectin interactions together with strong unfolding forces, both associated with Flo1 molecules. Single-molecule and single-cell data correlate with microscale cell adhesion behaviour, suggesting strongly that Flo1 mechanics is critical for yeast flocculation. These results favour a model in which not only weak lectin-sugar interactions are involved in yeast flocculation but also strong hydrophobic interactions resulting from protein unfolding.

  1. OOTW Force Design Tools

    Energy Technology Data Exchange (ETDEWEB)

    Bell, R.E.; Hartley, D.S.III; Packard, S.L.

    1999-05-01

    This report documents refined requirements for tools to aid the process of force design in Operations Other Than War (OOTWs). It recommends actions for the creation of one tool and work on other tools relating to mission planning. It also identifies the governmental agencies and commands with interests in each tool, from whom should come the user advisory groups overseeing the respective tool development activities. The understanding of OOTWs and their analytical support requirements has matured to the point where action can be taken in three areas: force design, collaborative analysis, and impact analysis. While the nature of the action and the length of time before complete results can be expected depends on the area, in each case the action should begin immediately. Force design for OOTWs is not a technically difficult process. Like force design for combat operations, it is a process of matching the capabilities of forces against the specified and implied tasks of the operation, considering the constraints of logistics, transport and force availabilities. However, there is a critical difference that restricts the usefulness of combat force design tools for OOTWs: the combat tools are built to infer non-combat capability requirements from combat capability requirements and cannot reverse the direction of the inference, as is required for OOTWs. Recently, OOTWs have played a larger role in force assessment, system effectiveness and tradeoff analysis, and concept and doctrine development and analysis. In the first Quadrennial Defense Review (QDR), each of the Services created its own OOTW force design tool. Unfortunately, the tools address different parts of the problem and do not coordinate the use of competing capabilities. These tools satisfied the immediate requirements of the QDR, but do not provide a long-term cost-effective solution.

  2. Sustained effect of resistance training on blood pressure and hand grip strength following a detraining period in elderly hypertensive women: a pilot study

    Directory of Open Access Journals (Sweden)

    Nascimento D da C

    2014-01-01

    Full Text Available Dahan da Cunha Nascimento,1,5,8 Ramires Alsamir Tibana,1,8 Franklin M Benik,2 Keila Elizabeth Fontana,3 Frederico Ribeiro Neto,8 Frederico Santos de Santana,5,8 Leopoldo Santos-Neto,4 Renato André Sousa Silva,1,5,6 Alessandro Oliveira Silva,1,7 Darlan Lopes Farias,1,7 Sandor Balsamo,4,5,8 Jonato Prestes1 1Postgraduate Program in Physical Education, Catholic University of Brasilia, Brasilia, Brazil; 2Department of Kinesiology and Sports Studies Graduate Program, Eastern Illinois University, Charleston, IL, USA; 3Faculty of Physical Education, University of Brasilia, Brasilia, Brazil; 4Graduate Program in Medical Sciences of the University of Brasilia, School of Medicine and Rheumatology Service, University Hospital of Brasilia (HUB, Brasilia, Brazil; 5Department of Physical Education, University Center Euro American University Center, Brasilia, Brazil; 6Center of Excellence in Medicine of Exercise (CEMEx, Brasilia, Brazil; 7Center University of Brasilia (UNICEUB, Brasilia, Brazil; 8Strength Training and Health Research Group (GEPEEFS, Brasilia, Brazil Introduction: Hypertension is the most prevalent modifiable risk factor with a high prevalence among older adults. Exercise is a nonpharmacological treatment shown to benefit all patients with hypertension. Objective: This study examined the effects of a 14-week moderate intensity resistance training program (RT on the maintenance of blood pressure and hand grip strength during an extended detraining period in elderly hypertensive women. Methods: Twelve hypertensive sedentary elderly women completed 14 weeks of whole body RT at a moderate perceived exertion following a detraining period of 14 weeks. Results: Following the training period, participants demonstrated an increase in absolute hand grip strength (P=0.001, relative hand grip strength (P=0.032 and a decrease of systolic (P=0.001, diastolic (P=0.008, and mean blood pressure (P=0.002 when compared to pre-exercise values. In addition, these

  3. Effect of low appendicular lean mass, grip strength, and gait speed on the functional outcome after surgery for distal radius fractures.

    Science.gov (United States)

    Roh, Young Hak; Noh, Jung Ho; Gong, Hyun Sik; Baek, Goo Hyun

    2017-12-01

    Patients with low appendicular lean mass plus slow gait speed or weak grip strength are at risk for poor functional recovery after surgery for distal radius fracture, even when they have similar radiologic outcomes. Loss of skeletal muscle mass and consequent loss in muscle function associate with aging, and this condition negatively impacts the activities of daily living and increases elderly individuals' frailty to falls. Thus, patients with low appendicular lean mass would show different functional recovery compared to those without this condition after surgery for distal radius fracture (DRF). This study compares the functional outcomes after surgery for DRF in patients with or without low appendicular lean mass plus slowness or weakness. A total of 157 patients older than 50 years of age with a DRF treated via volar plate fixation were enrolled in this prospective study. A definition of low appendicular lean mass with slowness or weakness was based on the consensus of the Asian Working Group for Sarcopenia. The researchers compared functional assessments (wrist range of motion and Michigan Hand Questionnaire [MHQ]) and radiographic assessments (radial inclination, volar tilt, ulnar variance, and articular congruity) 12 months after surgery between patients with and without low appendicular lean mass plus slowness or weakness. Multivariable regression analyses were performed to determine whether appendicular lean mass, grip strength, gait speed, patient demographic, or injury characteristics accounted for the functional outcomes. Patients with low appendicular lean mass plus slowness or weakness showed a significantly lower recovery of MHQ score than those in the control group throughout 12 months. There was no significant difference in the range of motion between the groups. The radiologic outcomes showed no significant difference between groups in terms of volar tilt, radial inclination, or ulnar variance. According to multivariable regression analysis

  4. Forced magnetic reconnection

    Science.gov (United States)

    Vekstein, G.

    2017-10-01

    This is a tutorial-style selective review explaining basic concepts of forced magnetic reconnection. It is based on a celebrated model of forced reconnection suggested by J. B. Taylor. The standard magnetohydrodynamic (MHD) theory of this process has been pioneered by Hahm & Kulsrud (Phys. Fluids, vol. 28, 1985, p. 2412). Here we also discuss several more recent developments related to this problem. These include energetics of forced reconnection, its Hall-mediated regime, and nonlinear effects with the associated onset of the secondary tearing (plasmoid) instability.

  5. Rate of force development

    DEFF Research Database (Denmark)

    Maffiuletti, Nicola A; Aagaard, Per; Blazevich, Anthony J

    2016-01-01

    development and to discuss various methodological considerations inherent to its evaluation for research and clinical purposes. Rate of force development (1) seems to be mainly determined by the capacity to produce maximal voluntary activation in the early phase of an explosive contraction (first 50-75 ms......The evaluation of rate of force development during rapid contractions has recently become quite popular for characterising explosive strength of athletes, elderly individuals and patients. The main aims of this narrative review are to describe the neuromuscular determinants of rate of force...

  6. Objective Force Warrior

    National Research Council Canada - National Science Library

    Shisler, Vernon

    2001-01-01

    This presentation concerns technology aimed at the dismounted soldier, Capstone demonstrations for FY06-07, fielding in the Objective Force time frame, strong interest in a lightweight weapon family...

  7. Packing force data correlations

    International Nuclear Information System (INIS)

    Heiman, S.M.

    1994-01-01

    One of the issues facing valve maintenance personnel today deals with an appropriate methodology for installing and setting valve packing that will minimize leak rates, yet ensure functionality of the the valve under all anticipated operating conditions. Several variables can affect a valve packing's ability to seal, such as packing bolt torque, stem finish, and lubrication. Stem frictional force can be an excellent overall indicator of some of the underlying conditions that affect the sealing characteristics of the packing and the best parameter to use when adjusting the packing. This paper addresses stem friction forces, analytically derives the equations related to these forces, presents a methodology for measuring these forces on valve stems, and attempts to correlate the data directly to the underlying variables

  8. Institutionalizing Security Force Assistance

    National Research Council Canada - National Science Library

    Binetti, Michael R

    2008-01-01

    .... It looks at the manner in which security assistance guidance is developed and executed. An examination of national level policy and the guidance from senior military and civilian leaders highlights the important role of Security Force Assistance...

  9. Hanscom Air Force Base

    Data.gov (United States)

    Federal Laboratory Consortium — MIT Lincoln Laboratory occupies 75 acres (20 acres of which are MIT property) on the eastern perimeter of Hanscom Air Force Base, which is at the nexus of Lexington,...

  10. On the fifth forces

    Science.gov (United States)

    Treder, Hans-Jürgen

    1991-03-01

    We discuss the possibility of “fifth forces” in relativistic gravitation theories of fourth order. The fifth force may be an analog to the “weak forces” in the theories of electroweak interactions.

  11. Bow Crushing Forces

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup

    1996-01-01

    The purpose of these notes is to present a basis for the estimation of the internal collision forces between conventinal merchant vessels and large volume offshore structures in the form of gravity-supported offshore installations and bridges crossing international shipping routes.The main emphasis...... is on the presentation of impact loads on fixed offshore structures due to bow collisions. The crushing forces are determined as functions of vessels size, vessels speed, bow profile, collision angles and eccentric impacts....

  12. Security Force Assistance

    Science.gov (United States)

    2009-05-01

    Group 8-59. Cultures may be individualistic or collectivist in their orientation. An individualist culture is one in which the ties between...relatively little weight on offensive and defensive operations from a U.S. perspective . However, when U.S. forces accompany foreign security forces (FSF) in...precedence when conducting SFA. As a result, the brigade combat team (BCT) may be a supported command from a U.S. perspective as well as acting as

  13. Joint Force Fires Coordination: Towards a Joint Force Answer

    National Research Council Canada - National Science Library

    Fearn, William

    1997-01-01

    .... Components compete for decisive effect not only with each other but with the joint force. The contemporary joint force is confederated, the joint force headquarters a weak arbitration authority...

  14. Report on the shearing, dissolution and analysis of GRIP-II rod 79-453 (validation rod); Light Water Breeder Reactor proof-of-breeding analytical support project

    International Nuclear Information System (INIS)

    Levitz, N.M.; Parks, J.E.; Winsch, I.O.; Meyer, R.J.; Graczyk, D.G.; Tomlinson, G.; Deeken, P.G.

    1981-10-01

    This report covers the processing and analysis of the fuel-bearing section (M-5138) of an irradiated experimental Light Water Breeder Reactor fuel rod, GRIP-II rod No. 79-453; this section has been designated the Validation Rod. Process steps included precision shearing of the rod into eight comminuted segments, dissolution of the segments, and chemical and radiometric analyses of the resulting solutions. The shearing and dissolution were carried out fully remotely in an existing pilot-scale facility installed in a shielded cell. Data are provided on physical parameters of the rod section and segments, uranium assays and isotopic abundances, and selected fission products. An error analysis of the individual measurements and analyses is included

  15. Gripping apparatus of a lifting device, especially in a core reactor for setting down and lifting fuel elements and fuel rods

    International Nuclear Information System (INIS)

    Dose, G.

    1976-01-01

    A gripping and lifting device is described for use with fuel elements and control rod means in a nuclear core reactor in which a carriage having a winch thereon supports a mast beneath the carriage in which is slidable a tubular body within which, in turn, is slidable a housing. Cables lead from the winch to the first body for vertical movement thereof while the housing has limited axial movement in the aforementioned body. On the lower end of the housing are two gripper devices, one for engagement with the control rods and the other for engagement with the fuel element. Separate actuators are provided for the two grippers, and sensing devices are included in the structure for sensing the positions of the grippers. A feature of the arrangement is that when the body is elevated and the housing moves downwardly therein to a stopped position, the gripper for the fuel element is locked in its respective position

  16. Estimation of precipitation rates by measurements of {sup 36}Cl in the GRIP ice core with the PSI/ETH tandem accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, G.; Baumgartner, S.; Beer, J. [EAWAG, Duebendorf (Switzerland); Synal, H.A. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Suter, M. [Eidgenoessische Technische Hochschule, Zurich (Switzerland)

    1997-09-01

    Within the European Greenland ice core project (GRIP) {sup 36}Cl AMS measurements have been performed on ice core samples from Summit (Greenland, 73{sup o}N, 37{sup o}W). Most data analysed so far are from the lower part of the ice core. The {sup 36}Cl concentration is well correlated with {delta}{sup 18}O, which is considered as a proxy for paleotemperatures. Assuming that the deposition rate of radionuclides is independent of {delta}{sup 18}O, {sup 36}Cl is used to estimate the relationship between accumulation and {delta}{sup 18}O. The results confirm that the rapid changes of {delta}{sup 18}O, the so-called Dansgaard-Oeschger events, are also reflected in the precipitation rate. (author) 1 fig., 3 refs.

  17. Long-term outcome of muscle strength in ulnar and median nerve injury: Comparing manual muscle strength testing, grip and pinch strength dynamometers and a new intrinsic muscle strength dynamometer

    NARCIS (Netherlands)

    A.R. Schreuders (Ton); M.E. Roebroeck (Marij); J.B. Jaquet (Jean); S.E.R. Hovius (Steven); H.J. Stam (Henk)

    2004-01-01

    textabstractObjective: To compare the outcome of muscle strength with manual muscle strength testing grip and pinch strength measurements and a dynamometer which allows for measurements of the intrinsic muscles of the hand in isolation (the Rotterdam Intrinsic Hand Myometer, RIHM). Methods:

  18. TEST-RETEST RELIABILITY OF HAND GRIP STRENGTH MEASUREMENT USING A JAMAR HAND DYNAMOMETER IN PATIENTS WITH ACUTE AND CHRONIC CERVICAL RADICULOPATHY

    Directory of Open Access Journals (Sweden)

    Ejazi G

    2017-12-01

    Full Text Available Background: To evaluate the test-retest reliability of Jamar hand held dynamometer for measuring handgrip strength (HGS in patients with acute and chronic cervical radiculopathy and to find out the difference in measurement of the handgrip strength between acute and chronic cervical radiculopathy. Methods: A prospective, observational and non-experimental, the comparative study design was used. A sample of 72 subjects (37 women and 35 men suffering from cervical radiculopathy were divided into two groups i.e., Group A(acute and Group B(chronic, handgrip strength was measured using Jamar hand held dynamometer on two occasions by the same rater with an interval of 7-days. Data collection was based on standard guidelines of American Society of Hand Therapists. Three gripping trials (measured in Kg with patient’s arm in standardized arm position were recorded. The data was analyzed from the mean score obtained from the sample. Result: One-way Analysis of Variance(ANOVA was used to evaluate test-retest reliability and Tukey-Kramer Multiple Comparison Test used to find the difference between handgrip strength among acute and chronic Cervical radiculopathy cases. Greater P-value (>0.05 in both testing session, as well as 95% of the confidence interval, shows the reliability of the instrument and lesser p-value (0.05 in female subjects shows no significant difference in handgrip strength between the two groups. Conclusion: Excellent test-retest reliability for hand grip strength measurement was measured in patients with acute and chronic cervical radiculopathy shows that the equipment could be used as an assessment tool for this patient and significant difference exists among male handgrip strength between acute and chronic cervical radiculopathy cases whereas no difference exists among female handgrip strength between acute and chronic cervical radiculopathy cases.

  19. Observations of C-Band Brightness Temperatures and Ocean Surface Wind Speed and Rain Rate from the Hurricane Imaging Radiometer (HIRAD) during GRIP and HS3

    Science.gov (United States)

    Miller, Timothy L.; James, M. W.; Roberts, J. B.; Jones, W. L.; Biswas, S.; Ruf, C. S.; Uhlhorn, E. W.; Atlas, R.; Black, P.; Albers, C.

    2013-01-01

    HIRAD flew on high-altitude aircraft over Earl and Karl during NASA s GRIP (Genesis and Rapid Intensification Processes) campaign in August - September of 2010, and at the time of this writing plans to fly over Atlantic tropical cyclones in September of 2012 as part of the Hurricane and Severe Storm Sentinel (HS3) mission. HIRAD is a new C-band radiometer using a synthetic thinned array radiometer (STAR) technology to obtain cross-track resolution of approximately 3 degrees, out to approximately 60 degrees to each side of nadir. By obtaining measurements of emissions at 4, 5, 6, and 6.6 GHz, observations of ocean surface wind speed and rain rate can be retrieved. This technique has been used for many years by precursor instruments, including the Stepped Frequency Microwave Radiometer (SFMR), which has been flying on the NOAA and USAF hurricane reconnaissance aircraft for several years to obtain observations within a single footprint at nadir angle. Results from the flights during the GRIP and HS3 campaigns will be shown, including images of brightness temperatures, wind speed, and rain rate. Comparisons will be made with observations from other instruments on the campaigns, for which HIRAD observations are either directly comparable or are complementary. Features such as storm eye and eye-wall, location of storm wind and rain maxima, and indications of dynamical features such as the merging of a weaker outer wind/rain maximum with the main vortex may be seen in the data. Potential impacts on operational ocean surface wind analyses and on numerical weather forecasts will also be discussed.

  20. Hurricane Imaging Radiometer (HIRAD) Observations of Brightness Temperatures and Ocean Surface Wind Speed and Rain Rate During NASA's GRIP and HS3 Campaigns

    Science.gov (United States)

    Miller, Timothy L.; James, M. W.; Roberts, J. B.; Jones, W. L.; Biswas, S.; Ruf, C. S.; Uhlhorn, E. W.; Atlas, R.; Black, P.; Albers, C.

    2012-01-01

    HIRAD flew on high-altitude aircraft over Earl and Karl during NASA s GRIP (Genesis and Rapid Intensification Processes) campaign in August - September of 2010, and plans to fly over Atlantic tropical cyclones in September of 2012 as part of the Hurricane and Severe Storm Sentinel (HS3) mission. HIRAD is a new C-band radiometer using a synthetic thinned array radiometer (STAR) technology to obtain spatial resolution of approximately 2 km, out to roughly 30 km each side of nadir. By obtaining measurements of emissions at 4, 5, 6, and 6.6 GHz, observations of ocean surface wind speed and rain rate can be retrieved. The physical retrieval technique has been used for many years by precursor instruments, including the Stepped Frequency Microwave Radiometer (SFMR), which has been flying on the NOAA and USAF hurricane reconnaissance aircraft for several years to obtain observations within a single footprint at nadir angle. Results from the flights during the GRIP and HS3 campaigns will be shown, including images of brightness temperatures, wind speed, and rain rate. Comparisons will be made with observations from other instruments on the campaigns, for which HIRAD observations are either directly comparable or are complementary. Features such as storm eye and eye-wall, location of storm wind and rain maxima, and indications of dynamical features such as the merging of a weaker outer wind/rain maximum with the main vortex may be seen in the data. Potential impacts on operational ocean surface wind analyses and on numerical weather forecasts will also be discussed.

  1. The relationship of birthweight, muscle size at birth and post-natal growth to grip strength in 9-year-old Indian children: findings from the Mysore Parthenon study.

    Science.gov (United States)

    Barr, J G; Veena, S R; Kiran, K N; Wills, A K; Winder, N R; Kehoe, S; Fall, C H D; Sayer, A A; Krishnaveni, G V

    2010-10-01

    Foetal development may permanently affect muscle function. Indian newborns have a low mean birthweight, predominantly due to low lean tissue and muscle mass. We aimed to examine the relationship of birthweight, and arm muscle area (AMA) at birth and post-natal growth to handgrip strength in Indian children. Grip strength was measured in 574 children aged 9 years, who had detailed anthropometry at birth and every 6-12 months post-natally. Mean (standard deviation (s.d.)) birthweight was 2863 (446) g. At 9 years, the children were short (mean height s.d. -0.6) and light (mean weight s.d. -1.1) compared with the World Health Organization growth reference. Mean (s.d.) grip strength was 12.7 (2.2) kg (boys) and 11.0 (2.0) kg (girls). Weight, length and AMA at birth, but not skinfold measurements at birth, were positively related to 9-year grip strength (β = 0.40 kg/s.d. increase in birthweight, P < 0.001; and β = 0.41 kg/s.d. increase in AMA, P < 0.001). Grip strength was positively related to 9-year height, body mass index and AMA and to gains in these measurements from birth to 2 years, 2-5 years and 5-9 years (P < 0.001 for all). The associations between birth size and grip strength were attenuated but remained statistically significant for AMA after adjusting for 9-year size. We conclude that larger overall size and muscle mass at birth are associated with greater muscle strength in childhood, and that this is mediated mainly through greater post-natal size. Poorer muscle development in utero is associated with reduced childhood muscle strength.

  2. Age- and sex-standardised lean and fat indices derived from bioelectrical impedance analysis for ages 7-11 years: functional associations with cardio-respiratory fitness and grip strength.

    Science.gov (United States)

    Sherriff, Andrea; Wright, Charlotte M; Reilly, John J; McColl, John; Ness, Andy; Emmett, Pauline

    2009-06-01

    Indices for lean and fat mass adjusted for height derived from bioelectrical impedance for children aged 7 years have been published previously and their usefulness in the clinical assessment of undernutrition has been demonstrated. However, there is a need for norms that cover a wider age range and to explore their functional significance. The aim of the present study is to derive lean and fat indices for children aged 7-11 years and investigate associations with objective measures of cardio-respiratory fitness and grip strength. Subjects were 9574 children participating in the Avon Longitudinal Study of Parents and Children (ALSPAC). Bioelectrical impedance analysis (BIA) data collected longitudinally between ages 7 and 11 were used to derive lean and fat indices using the method of standardised residuals. Cardio-respiratory fitness (CRF) (9 years) and grip strength (11 years) were also measured. Correlation coefficients and 95 % CI were calculated to assess the strength of association between lean index, fat index and CRF and grip strength. Equations for calculating lean and fat indices in children aged 7-11 years relative to the ALSPAC population are presented. Lean index was linearly associated with CRF (rboys 0.20 (95 % CI 0.15, 0.25), rgirls 0.26 (95 % CI 0.22, 0.30)) and grip strength (rboys 0.29 (95 % CI 0.26, 0.32), rgirls 0.26 (95 % CI 0.23, 0.29)). BMI showed slightly weaker associations, while fat index was unrelated to either CRF or grip strength. Lean indices relate to muscle function and fitness while fat index does not.

  3. Predicting Diaphyseal Cortical Bone Status Using Measures of Muscle Force Capacity.

    Science.gov (United States)

    Higgins, Simon; Sokolowski, Chester M; Vishwanathan, Megha; Anderson, Jessica G; Schmidt, Michael D; Lewis, Richard D; Evans, Ellen M

    2018-02-16

    Muscle cross sectional area (MCSA) is often used as a surrogate for the forces applied to bones during physical activity. Though MCSA is a strong predictor of cortical bone status, its use makes assumptions about the relationship between muscle size and force that are inaccurate. Furthermore, to measure MCSA and other muscle force surrogates typically requires expensive and/or radiative laboratory equipment. Thus, this study aimed to determine whether clinical lab- and field-based methodologies for measuring muscular force capacity accounted for similar variance in diaphyseal cortical bone status as a commonly used muscular force surrogate; MCSA, at the mid-tibia in young men and women. Healthy young adults (n = 142, 19.7 ± 0.7 yo, 52.8% female) were assessed via peripheral quantitative computed tomography at the mid-tibia for cortical bone status and MCSA. Muscle force capacity was measured via Biodex dynamometer, Nottingham leg extensor power rig, and Vertec vertical jump. Regression analysis compared the independent variance predicted by each muscle force measure to that of MCSA, accounting for relevant confounders. MCSA, knee extension peak torque, and peak anaerobic power from vertical jump were independent predictors of select cortical structural outcomes (cortical thickness and area, periosteal and endosteal circumference, and estimated strength) accounting for up to 78.4% of the variance explained (all p<.05). However, cortical volumetric bone mineral density was unrelated to any measure or surrogate of muscle force capacity. MCSA is a strong independent predictor of cortical bone structure; however, both lab- and field-based measures of peak torque and/or peak anaerobic power are promising alternatives, explaining similar and sometimes greater variance than MCSA.

  4. Forces in strategy formation

    DEFF Research Database (Denmark)

    Steensen, Elmer Fly; Sanchez, Ron

    2008-01-01

    This chapter proposes that organizational strategy formation should be characterized theoretically as a process that is subject to several interacting forces, rather than represented by separate discrete decisionmodels or theoretic perspectives, as is commonly done in the strategic management...... literature. Based on an extensive review of relevant theory and empirical work in strategic decision-making, organizational change theory, cognitive and social psychology, and strategy processes, seven kinds of ''forces'' - rational, imposed, teleological, learning, political, heuristic, and social...... - are identified as interacting in and having significant influence on the strategy formation process. It is further argued that by applying a holistic ''forces-view'' of the significant and interacting influences on strategy formation, we can better understand the dynamics and challenges in managing the process...

  5. Electrochemical force microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Kalinin, Sergei V.; Jesse, Stephen; Collins, Liam F.; Rodriguez, Brian J.

    2017-01-10

    A system and method for electrochemical force microscopy are provided. The system and method are based on a multidimensional detection scheme that is sensitive to forces experienced by a biased electrode in a solution. The multidimensional approach allows separation of fast processes, such as double layer charging, and charge relaxation, and slow processes, such as diffusion and faradaic reactions, as well as capturing the bias dependence of the response. The time-resolved and bias measurements can also allow probing both linear (small bias range) and non-linear (large bias range) electrochemical regimes and potentially the de-convolution of charge dynamics and diffusion processes from steric effects and electrochemical reactivity.

  6. ForcePAD

    DEFF Research Database (Denmark)

    Lindemann, J.; Damkilde, Lars

    2009-01-01

    ForcePAD is a 2-dimensional finite element application that started as a concept application for finite element modeling. Over the course of 10 years the application has been evolved into an application that is used extensively in both an educational setting as well as a tool for design and engin......ForcePAD is a 2-dimensional finite element application that started as a concept application for finite element modeling. Over the course of 10 years the application has been evolved into an application that is used extensively in both an educational setting as well as a tool for design...

  7. due to Capillary Forces

    Directory of Open Access Journals (Sweden)

    Hassen M. Ouakad

    2009-01-01

    Full Text Available We present modeling and analysis for the static behavior and collapse instabilities of doubly-clamped and cantilever microbeams subjected to capillary forces. These forces can be as a result of a volume of liquid trapped underneath the microbeam during the rinsing and drying process in fabrication. The model considers the microbeam as a continuous medium, the capillary force as a nonlinear function of displacement, and accounts for the mid-plane stretching and geometric nonlinearities. The capillary force is assumed to be distributed over a specific length underneath the microbeam. The Galerkin procedure is used to derive a reduced-order model consisting of a set of nonlinear algebraic and differential equations that describe the microbeams static and dynamic behaviors. We study the collapse instability, which brings the microbeam from its unstuck configuration to touch the substrate and gets stuck in the so-called pinned configuration. We calculate the pull-in length that distinguishes the free from the pinned configurations as a function of the beam thickness and gap width for both microbeams. Comparisons are made with analytical results reported in the literature based on the Ritz method for linear and nonlinear beam models. The instability problem, which brings the microbeam from a pinned to adhered configuration is also investigated. For this case, we use a shooting technique to solve the boundary-value problem governing the deflection of the microbeams. The critical microbeam length for this second instability is also calculated.

  8. The fifth force

    International Nuclear Information System (INIS)

    Fischbach, E.; Sudarsky, D.; Szafer, A.; Talmadge, C.; Aronson, S.H.

    1986-01-01

    We present a phenomenological description of the ''fifth force'' which focuses on the implications of the existing data from satellite and geophysical measurements of gravity, the Eoetvoes experiment, decays into hyperphotons, and the energy-dependence of the K 0 - anti K 0 parameters

  9. Magnetic Force Microscopy

    NARCIS (Netherlands)

    Abelmann, Leon

    Principle of MFM In magnetic force microscopy (MFM), the magnetic stray field above a very flat specimen, or sample, is detected by placing a small magnetic element, the tip, mounted on a cantilever spring very close to the surface of the sample (Figure 1). Typical dimensions are a cantilever length

  10. Separation problems and forcing

    Czech Academy of Sciences Publication Activity Database

    Zapletal, Jindřich

    2013-01-01

    Roč. 13, č. 1 (2013), s. 1350002 ISSN 0219-0613 R&D Projects: GA AV ČR IAA100190902 Institutional research plan: CEZ:AV0Z10190503 Keywords : separation * set of uniqueness * forcing Subject RIV: BA - General Mathematics Impact factor: 0.364, year: 2012 http://www.worldscientific.com/doi/abs/10.1142/S0219061313500025

  11. Allegiance: Egypt Security Forces

    Science.gov (United States)

    2013-12-01

    expected after the uprising of 2011 never truly materialized; the Interior Ministry instituted various cosmetic changes, but its basic construct and...military forces located there. The masked men appeared to be shooting and the army responded, shooting back.284 Whatever the stories

  12. Activation force splines

    DEFF Research Database (Denmark)

    Engell-Nørregård, Morten Pol; Erleben, Kenny

    We present a method for simulating the active contraction of deformable models, usable for interactive animation of soft deformable objects. We present a novel physical principle as the governing equation for the coupling between the low dimensional 1D activation force model and the higher...

  13. Fifth force, sixth force and all that

    International Nuclear Information System (INIS)

    Recami, E.; Tonin Zanchin, V.

    1988-01-01

    In the recent literature, a few claims appeared about possible deviations from the ordinary gravitational laws (both at the terrestrial and at the galactic level). The experimental evidence does not seem to be conclusive; nor its is clear if new forces are showing up, or if we have to accept actual deviations from Newton or Einstein gravitation (in the latter case, the validity of the very Equivalence Principle might be on the stage). In such a situation, the attempts by various authors at explaining the ''new effects'' just on the basis of the ordinary theory of General Relativity (for instance, in terms of quantum gravity) can be regarded as logically instance, in terms of quantum gravity) can be regarded as logically questionable. In this pedagogically oriented paper, the problem is approached within the classical realm, by exploring whether the possible new effects can be accounted for through minimal modifications of the standard formulatiaon of General Relativity: in particular, through exploitation and extension of the role of the cosmological constant

  14. Biodegradable Piezoelectric Force Sensor.

    Science.gov (United States)

    Curry, Eli J; Ke, Kai; Chorsi, Meysam T; Wrobel, Kinga S; Miller, Albert N; Patel, Avi; Kim, Insoo; Feng, Jianlin; Yue, Lixia; Wu, Qian; Kuo, Chia-Ling; Lo, Kevin W-H; Laurencin, Cato T; Ilies, Horea; Purohit, Prashant K; Nguyen, Thanh D

    2018-01-30

    Measuring vital physiological pressures is important for monitoring health status, preventing the buildup of dangerous internal forces in impaired organs, and enabling novel approaches of using mechanical stimulation for tissue regeneration. Pressure sensors are often required to be implanted and directly integrated with native soft biological systems. Therefore, the devices should be flexible and at the same time biodegradable to avoid invasive removal surgery that can damage directly interfaced tissues. Despite recent achievements in degradable electronic devices, there is still a tremendous need to develop a force sensor which only relies on safe medical materials and requires no complex fabrication process to provide accurate information on important biophysiological forces. Here, we present a strategy for material processing, electromechanical analysis, device fabrication, and assessment of a piezoelectric Poly-l-lactide (PLLA) polymer to create a biodegradable, biocompatible piezoelectric force sensor, which only employs medical materials used commonly in Food and Drug Administration-approved implants, for the monitoring of biological forces. We show the sensor can precisely measure pressures in a wide range of 0-18 kPa and sustain a reliable performance for a period of 4 d in an aqueous environment. We also demonstrate this PLLA piezoelectric sensor can be implanted inside the abdominal cavity of a mouse to monitor the pressure of diaphragmatic contraction. This piezoelectric sensor offers an appealing alternative to present biodegradable electronic devices for the monitoring of intraorgan pressures. The sensor can be integrated with tissues and organs, forming self-sensing bionic systems to enable many exciting applications in regenerative medicine, drug delivery, and medical devices.

  15. Design and Evaluation of a Cable-Driven fMRI-Compatible Haptic Interface to Investigate Precision Grip Control.

    Science.gov (United States)

    Vigaru, Bogdan; Sulzer, James; Gassert, Roger

    2015-10-01

    Our hands and fingers are involved in almost all activities of daily living and, as such, have a disproportionately large neural representation. Functional magnetic resonance imaging investigations into the neural control of the hand have revealed great advances, but the harsh MRI environment has proven to be a challenge to devices capable of delivering a large variety of stimuli necessary for well-controlled studies. This paper presents a fMRI-compatible haptic interface to investigate the neural mechanisms underlying precision grasp control. The interface, located at the scanner bore, is controlled remotely through a shielded electromagnetic actuation system positioned at the end of the scanner bed and then through a high stiffness, low inertia cable transmission. We present the system design, taking into account requirements defined by the biomechanics and dynamics of the human hand, as well as the fMRI environment. Performance evaluation revealed a structural stiffness of 3.3 N/mm, renderable forces up to 94 N, and a position control bandwidth of at least 19 Hz. MRI-compatibility tests showed no degradation in the operation of the haptic interface or the image quality. A preliminary fMRI experiment during a pilot study validated the usability of the haptic interface, illustrating the possibilities offered by this device.

  16. Memory-guided force control in healthy younger and older adults.

    Science.gov (United States)

    Neely, Kristina A; Samimy, Shaadee; Blouch, Samantha L; Wang, Peiyuan; Chennavasin, Amanda; Diaz, Michele T; Dennis, Nancy A

    2017-08-01

    Successful performance of a memory-guided motor task requires participants to store and then recall an accurate representation of the motor goal. Further, participants must monitor motor output to make adjustments in the absence of visual feedback. The goal of this study was to examine memory-guided grip force in healthy younger and older adults and compare it to performance on behavioral tasks of working memory. Previous work demonstrates that healthy adults decrease force output as a function of time when visual feedback is not available. We hypothesized that older adults would decrease force output at a faster rate than younger adults, due to age-related deficits in working memory. Two groups of participants, younger adults (YA: N = 32, mean age 21.5 years) and older adults (OA: N = 33, mean age 69.3 years), completed four 20-s trials of isometric force with their index finger and thumb, equal to 25% of their maximum voluntary contraction. In the full-vision condition, visual feedback was available for the duration of the trial. In the no vision condition, visual feedback was removed for the last 12 s of each trial. Participants were asked to maintain constant force output in the absence of visual feedback. Participants also completed tasks of word recall and recognition and visuospatial working memory. Counter to our predictions, when visual feedback was removed, younger adults decreased force at a faster rate compared to older adults and the rate of decay was not associated with behavioral performance on tests of working memory.

  17. Retraining and assessing hand movement after stroke using the MusicGlove: comparison with conventional hand therapy and isometric grip training.

    Science.gov (United States)

    Friedman, Nizan; Chan, Vicky; Reinkensmeyer, Andrea N; Beroukhim, Ariel; Zambrano, Gregory J; Bachman, Mark; Reinkensmeyer, David J

    2014-04-30

    It is thought that therapy should be functional, be highly repetitive, and promote afferent input to best stimulate hand motor recovery after stroke, yet patients struggle to access such therapy. We developed the MusicGlove, an instrumented glove that requires the user to practice gripping-like movements and thumb-finger opposition to play a highly engaging, music-based, video game. The purpose of this study was to 1) compare the effect of training with MusicGlove to conventional hand therapy 2) determine if MusicGlove training was more effective than a matched form of isometric hand movement training; and 3) determine if MusicGlove game scores predict clinical outcomes. 12 chronic stroke survivors with moderate hemiparesis were randomly assigned to receive MusicGlove, isometric, and conventional hand therapy in a within-subjects design. Each subject participated in six one-hour treatment sessions three times per week for two weeks, for each training type, for a total of 18 treatment sessions. A blinded rater assessed hand impairment before and after each training type and at one-month follow-up including the Box and Blocks (B & B) test as the primary outcome measure. Subjects also completed the Intrinsic Motivation Inventory (IMI). Subjects improved hand function related to grasping small objects more after MusicGlove compared to conventional training, as measured by the B & B score (improvement of 3.21±3.82 vs. -0.29±2.27 blocks; P=0.010) and the 9 Hole Peg test (improvement of 2.14±2.98 vs. -0.85±1.29 pegs/minute; P=0.005). There was no significant difference between training types in the broader assessment batteries of hand function. Subjects benefited less from isometric therapy than MusicGlove training, but the difference was not significant (P>0.09). Subjects sustained improvements in hand function at a one month follow-up, and found the MusicGlove more motivating than the other two therapies, as measured by the IMI. MusicGlove games scores correlated

  18. Effects of task complexity on coordination of inter-limb and within-limb forces in static bimanual manipulation.

    Science.gov (United States)

    Krishnan, Vennila; Jaric, Slobodan

    2010-10-01

    Coordination of the hand grip (G; acting normally to the grasping surface) and load forces (L; acting in parallel) in bimanual static tasks was studied. L symmetry (either the magnitude or direction) and frequency were manipulated in healthy participants (N = 14). More complex tasks (i.e., the higher frequency and/or asymmetric ones) revealed expected deterioration in both the task performance (accuracy of the prescribed L force profiles) and force coordination (G/L ratio and G-L correlation) suggesting importance of L frequency and symmetry in prehension activities. However, the same tasks revealed a more prominent deterioration of interlimb than the within-limb force coordination. This could be interpreted by two partly different and noncompeting neural control mechanisms where the coordination of interlimb forces may be based on ad-hoc and task-specific muscle coordination (often referred to as muscle synergies) while the within-limb coordination of G and L could be based on more stable and partly reflex mechanisms.

  19. Oxytocin decreases handgrip force in reaction to infant crying in females without harsh parenting experiences.

    Science.gov (United States)

    Bakermans-Kranenburg, Marian J; van Ijzendoorn, Marinus H; Riem, Madelon M E; Tops, Mattie; Alink, Lenneke R A

    2012-11-01

    Infant crying can elicit sensitive caregiving as well as hostility and harsh parenting responses. In the current study (N = 42 females) with a double-blind experimental design, we tested the effect of intranasal oxytocin administration on the use of excessive force using a hand-grip dynamometer during listening to infant cry sounds. Participants' experiences with harsh parental discipline during childhood were found to moderate the effect of oxytocin administration on the use of excessive force. Participants' whose parents did not discipline them harshly used less excessive force in the oxytocin condition, but for participants who were disciplined harshly there was no difference between the oxytocin and placebo condition. Such effects were not found during listening to infant laughter. We conclude that early caregiving experiences constitute an important moderator of the prosocial and/or stress-reducing effects of oxytocin. Oxytocin administration may increase trust and cooperation in individuals with supportive backgrounds, but not generate this effect in individuals who as a consequence of unfavorable early caregiving experiences may have a bias toward negative interpretation of social cues.

  20. Force Modulator System

    Energy Technology Data Exchange (ETDEWEB)

    Redmond Clark

    2009-04-30

    Many metal parts manufacturers use large metal presses to shape sheet metal into finished products like car body parts, jet wing and fuselage surfaces, etc. These metal presses take sheet metal and - with enormous force - reshape the metal into a fully formed part in a manner of seconds. Although highly efficient, the forces involved in forming metal parts also damage the press itself, limit the metals used in part production, slow press operations and, when not properly controlled, cause the manufacture of large volumes of defective metal parts. To date, the metal-forming industry has not been able to develop a metal-holding technology that allows full control of press forces during the part forming process. This is of particular importance in the automotive lightweighting efforts under way in the US automotive manufacturing marketplace. Metalforming Controls Technology Inc. (MC2) has developed a patented press control system called the Force Modulator that has the ability to control these press forces, allowing a breakthrough in stamping process control. The technology includes a series of hydraulic cylinders that provide controlled tonnage at all points in the forming process. At the same time, the unique cylinder design allows for the generation of very high levels of clamping forces (very high tonnages) in very small spaces; a requirement for forming medium and large panels out of HSS and AHSS. Successful production application of these systems testing at multiple stamping operations - including Ford and Chrysler - has validated the capabilities and economic benefits of the system. Although this technology has been adopted in a number of stamping operations, one of the primary barriers to faster adoption and application of this technology in HSS projects is system cost. The cost issue has surfaced because the systems currently in use are built for each individual die as a custom application, thus driving higher tooling costs. This project proposed to better

  1. Suicide and forced marriage.

    Science.gov (United States)

    Pridmore, Saxby; Walter, Garry

    2013-03-01

    The prevailing view that the vast majority of those who complete suicide have an underlying psychiatric disorder has been recently challenged by research on the contribution of "predicaments", in the absence of mental illness, to suicide. In this paper, we sought data to support the notion that forced marriage may lead to suicide without the presence of psychiatric disorder. Historical records, newspapers, and the electronic media were searched for examples. Two examples from ancient times and six from the last hundred years were located and described. These cases suggest that forced marriage may lead to suicide and complements earlier findings that loss of fortune, health, liberty, and reputation may lead to suicide in the absence of mental disorder.

  2. Flora rapid reaction forces

    Directory of Open Access Journals (Sweden)

    Виктор Васильевич Туганаев

    2015-10-01

    Full Text Available Flora rapid reaction forces ­– there are explerents that have high productivity and weak competitiveness. Their innately functional allocation is to plant disturbed acres as soon as possible preventing by that biosphere homeostasis disturbance. Disturbed acres were used to take place in geological history. Nowadays they take especially big areas. Considering a historical line of Dactylis glomerata L. authors suggest to separate out an especial group of anthropochores which they call medieophytes

  3. Air Force Leadership Diversity

    Science.gov (United States)

    2017-04-06

    College, Air University, Maxwell AFB, AL. He grew up as part of an Air Force family, entered active duty in 1996, and is a career Aircraft Maintenance... artificially limit them to capping out at O-6 if we want to encourage diversity in our most senior leadership levels as we seek to create a stronger...but I am not sure it does. I find it interesting that as of 31 December 2016 the Deputy Chief of Staff for Intelligence , Surveillance and

  4. The task force process

    International Nuclear Information System (INIS)

    Applegate, J.S.

    1995-01-01

    This paper focuses on the unique aspects of the Fernald Citizens Task Force process that have contributed to a largely successful public participation effort at Fernald. The Fernald Citizens Task Force passed quickly by many procedural issues. Instead, the Task Force concentrated on (a) educating itself about the site, its problems, and possible solutions, and (b) choosing a directed way to approach its mandate: To make recommendations on several open-quotes big pictureclose quotes issues, including future use of the site, cleanup levels, waste disposition, and cleanup priorities. This paper presents the approach used at Fernald for establishing and running a focused site-specific advisory board, the key issues that have been faced, and how these issues were resolved. The success of Fernald in establishing a strong and functioning site-specific advisory board serves as a useful model for other DOE facilities, although the Fernald model is just one of many approaches that can be taken. However, the approach presented here has worked extremely well for Fernald

  5. Gap Task Force

    CERN Multimedia

    Lissuaer, D

    One of the more congested areas in the ATLAS detector is the GAP region (the area between the Barrel Calorimeter and the End Cap calorimeter) where Inner Detector services, LAr Services and some Tile services all must co-habitat in a very limited area. It has been clear for some time that the space in the GAP region is not sufficient to accommodate all that is needed. In the last few month additional problems of routing all the services to Z=0 have been encountered due to the very limited space between the Tile Calorimeter and the first layer of Muon chambers. The Technical Management Board (TMB) and the Executive Board (EB) decided in the middle of March to establish a Task Force to look at this problem and come up with a solution within well-specified guidelines. The task force consisted of experts from the ID, Muon, Liquid Argon and Tile systems in addition to experts from the Technical Coordination team and the Physics coordinator. The task force held many meetings and in general there were some very l...

  6. ``Force,'' ontology, and language

    Science.gov (United States)

    Brookes, David T.; Etkina, Eugenia

    2009-06-01

    We introduce a linguistic framework through which one can interpret systematically students’ understanding of and reasoning about force and motion. Some researchers have suggested that students have robust misconceptions or alternative frameworks grounded in everyday experience. Others have pointed out the inconsistency of students’ responses and presented a phenomenological explanation for what is observed, namely, knowledge in pieces. We wish to present a view that builds on and unifies aspects of this prior research. Our argument is that many students’ difficulties with force and motion are primarily due to a combination of linguistic and ontological difficulties. It is possible that students are primarily engaged in trying to define and categorize the meaning of the term “force” as spoken about by physicists. We found that this process of negotiation of meaning is remarkably similar to that engaged in by physicists in history. In this paper we will describe a study of the historical record that reveals an analogous process of meaning negotiation, spanning multiple centuries. Using methods from cognitive linguistics and systemic functional grammar, we will present an analysis of the force and motion literature, focusing on prior studies with interview data. We will then discuss the implications of our findings for physics instruction.

  7. Force transmission in epithelial tissues.

    Science.gov (United States)

    Vasquez, Claudia G; Martin, Adam C

    2016-03-01

    In epithelial tissues, cells constantly generate and transmit forces between each other. Forces generated by the actomyosin cytoskeleton regulate tissue shape and structure and also provide signals that influence cells' decisions to divide, die, or differentiate. Forces are transmitted across epithelia because cells are mechanically linked through junctional complexes, and forces can propagate through the cell cytoplasm. Here, we review some of the molecular mechanisms responsible for force generation, with a specific focus on the actomyosin cortex and adherens junctions. We then discuss evidence for how these mechanisms promote cell shape changes and force transmission in tissues. © 2016 Wiley Periodicals, Inc.

  8. Imaginary Pasts: Colonisation, Migration and Loss in J.G. Farrell’s 'The Singapore Grip' and in Amitav Ghosh’s 'The Glass Palace'

    Directory of Open Access Journals (Sweden)

    Michael C. Prusse

    2009-11-01

    Full Text Available A quotation from each of the two novels that form the background for this paper will immediately establish why these narratives are pertinent to the central theme of the ‘Moving Cultures, Shifting Identities Conference’ that took place at Flinders University in Adelaide early in December 2007. In both texts the theme of migration in the context of imperialism plays a central role and, moreover, both clearly spell out what tremendous impact moving between and across cultures has on the lives of people, who are thoroughly affected and marked by such encounters. Matthew Webb, one of the protagonists of J.G. Farrell’s The Singapore Grip (1978, renders his perception of the phenomenon of migration in the wake of imperial expansion as follows: ‘One of the most astounding things about our Empire … is the way we’ve transported vast populations across the globe as cheap labour’. Matthew, a critical observer of British imperialism but still a member of colonial society and a British citizen, thus provides the reader with an insight regarding the economic motivation behind such enforced movements of people.

  9. A virtual reality system integrated with robot-assisted haptics to simulate pinch-grip task: Motor ingredients for the assessment in chronic stroke.

    Science.gov (United States)

    Yeh, Shih-Ching; Lee, Si-Huei; Chan, Rai-Chi; Chen, Shuya; Rizzo, Albert

    2014-01-01

    Among numerous studies on virtual reality (VR) technology for motor rehabilitation, the majorities have only used it as a motor training system and did not use the kinematic or kinetic information obtained as the basis for therapeutic effect assessment. Incorporating the kinematic and kinetic information acquired through a robot-assisted VR system on pinch-grip training, this study intends to propose novel motor ingredients represented as indices for the interpretation of motor behaviors and verify the efficacy of them for the assessment in chronic stroke. Clinical trials were conducted on eight stroke patients and clinical assessments were made as the objective standard. Non-parametric test and correlation analysis were performed on results of motor indices and clinical assessments. Non-parametric test indicated that 50% of the motor indices significantly improved while the others showed a trend of improvement, consisting with the findings in clinical assessments. Correlation analysis showed that the three clinical assessment items were correlated to items in the motor ingredients. The proposed motor ingredients gathered from the robot-assisted VR training system were able to contribute to the assessment of therapeutic effect in chronic stroke and were capable for the interpretation of behavior phases.

  10. Characterization of luminescence properties of insoluble mineral grains extracted from the Greenland Summit GRIP ice core, and their potential for luminescence dating

    International Nuclear Information System (INIS)

    Lepper, Kenneth.; Siggaard-Andersen, M.-L.Marie-Louise; Larsen, N.A.Niels Agersnap; Hammer, C.U.Claus U.; McKeever, S.W.S.Stephen W.S.

    2001-01-01

    We describe several optically stimulated luminescence (OSL) and thermoluminescence (TL) properties of insoluble mineral grains extracted from the Greenland summit GRIP ice core in order to examine the potential of these techniques for age determination of these materials. Since the dust grains examined in this work were exposed to natural and artificial light at many stages prior to luminescence analysis, the purpose of the experiments reported herein was not to make age determinations, but rather to evaluate the general suitability of dust grains extracted from ice cores for luminescence dating. The measurements indicate that the fine-grained dust has a wide dynamic dose response range, with limited saturation effects being seen until absorbed doses of ∼1000 Gy. Furthermore, the sample's TL and OSL signals were stable over the time intervals evaluated in this study and readily susceptible to bleaching by exposure to sunlight. These three properties form a stable base for the development of luminescence dating procedures for insoluble mineral grains recovered from ice cores. The experiments demonstrate that such procedures can be carried out on sample masses of less than 1 mg

  11. Hook-up of GluA2, GRIP and liprin-α for cholinergic muscarinic receptor-dependent LTD in the hippocampus

    Directory of Open Access Journals (Sweden)

    Wu Long-Jun

    2009-06-01

    Full Text Available Abstract The molecular mechanism underlying muscarinic acetylcholine receptor-dependent LTD (mAChR-LTD in the hippocampus is less studied. In a recent study, a novel mechanism is described. The induction of mAChR-LTD required the activation of protein tyrosine phosphatase (PTP, and the expression was mediated by AMPA receptor endocytosis via interactions between GluA2, GRIP and liprin-α. The hook-up of these proteins may result in the recruitment of leukocyte common antigen-related receptor (LAR, a PTP that is known to be involved in AMPA receptor trafficking. Interestingly, the similar molecular interaction cannot be applied to mGluR-LTD, despite the fact that the same G-protein involved in LTD is activated by both mAChR and mGluR. This discovery provides key molecular insights for cholinergic dependent cognitive function, and mAChR-LTD can serve as a useful cellular model for studying the roles of cholinergic mechanism in learning and memory.

  12. Light Intensity physical activity and sedentary behavior in relation to body mass index and grip strength in older adults: cross-sectional findings from the Lifestyle Interventions and Independence for Elders (LIFE study.

    Directory of Open Access Journals (Sweden)

    David Bann

    Full Text Available Identifying modifiable determinants of fat mass and muscle strength in older adults is important given their impact on physical functioning and health. Light intensity physical activity and sedentary behavior are potential determinants, but their relations to these outcomes are poorly understood. We evaluated associations of light intensity physical activity and sedentary time-assessed both objectively and by self-report-with body mass index (BMI and grip strength in a large sample of older adults.We used cross-sectional baseline data from 1130 participants of the Lifestyle Interventions and Independence for Elders (LIFE study, a community-dwelling sample of relatively sedentary older adults (70-89 years at heightened risk of mobility disability. Time spent sedentary and in light intensity activity were assessed using an accelerometer worn for 3-7 days (Actigraph GT3X and by self-report. Associations between these exposures and measured BMI and grip strength were evaluated using linear regression.Greater time spent in light intensity activity and lower sedentary times were both associated with lower BMI. This was evident using objective measures of lower-light intensity, and both objective and self-reported measures of higher-light intensity activity. Time spent watching television was positively associated with BMI, while reading and computer use were not. Greater time spent in higher but not lower intensities of light activity (assessed objectively was associated with greater grip strength in men but not women, while neither objectively assessed nor self-reported sedentary time was associated with grip strength.In this cross-sectional study, greater time spent in light intensity activity and lower sedentary times were associated with lower BMI. These results are consistent with the hypothesis that replacing sedentary activities with light intensity activities could lead to lower BMI levels and obesity prevalence among the population of older

  13. Vitamin D(3) at 50x AI attenuates the decline in paw grip endurance, but not disease outcomes, in the G93A mouse model of ALS, and is toxic in females.

    Science.gov (United States)

    Gianforcaro, Alexandro; Solomon, Jesse A; Hamadeh, Mazen J

    2013-01-01

    We previously demonstrated that dietary vitamin D(3) at 10x the adequate intake (AI) attenuates the decline in functional capacity in the G93A mouse model of ALS. We hypothesized that higher doses would elicit more robust changes in functional and disease outcomes. To determine the effects of dietary vitamin D(3) at 50xAI on functional outcomes (motor performance, paw grip endurance) and disease severity (clinical score), as well as disease onset, disease progression and lifespan in the transgenic G93A mouse model of ALS. Starting at age 25 d, 100 G93A mice (55 M, 45 F) were provided ad libitum with either an adequate (AI; 1 IU D(3)/g feed) or high (HiD; 50 IU D(3)/g feed) vitamin D(3) diet. HiD females consumed 9% less food corrected for body weight vs. AI females (P = 0.010). HiD mice had a 12% greater paw grip endurance over time between age 60-141 d (P = 0.015), and a 37% greater score during disease progression (P = 0.042) vs. AI mice. Although HiD females had a non-significant 31% greater CS prior to disease onset vs. AI females, they exhibited a significant 20% greater paw grip endurance AUC (P = 0.020) when corrected for clinical score. Dietary D(3) supplementation at 50x the adequate intake attenuated the decline in paw grip endurance, but did not influence age at disease onset, hindlimb paralysis or endpoint in the transgenic G93A mouse model of ALS. Furthermore, females may have reached the threshold for vitamin D(3) toxicity as evidence by reduced food intake and greater disease severity prior to disease onset.

  14. Light Intensity physical activity and sedentary behavior in relation to body mass index and grip strength in older adults: cross-sectional findings from the Lifestyle Interventions and Independence for Elders (LIFE) study.

    Science.gov (United States)

    Bann, David; Hire, Don; Manini, Todd; Cooper, Rachel; Botoseneanu, Anda; McDermott, Mary M; Pahor, Marco; Glynn, Nancy W; Fielding, Roger; King, Abby C; Church, Timothy; Ambrosius, Walter T; Gill, Thomas M; Gill, Thomas

    2015-01-01

    Identifying modifiable determinants of fat mass and muscle strength in older adults is important given their impact on physical functioning and health. Light intensity physical activity and sedentary behavior are potential determinants, but their relations to these outcomes are poorly understood. We evaluated associations of light intensity physical activity and sedentary time-assessed both objectively and by self-report-with body mass index (BMI) and grip strength in a large sample of older adults. We used cross-sectional baseline data from 1130 participants of the Lifestyle Interventions and Independence for Elders (LIFE) study, a community-dwelling sample of relatively sedentary older adults (70-89 years) at heightened risk of mobility disability. Time spent sedentary and in light intensity activity were assessed using an accelerometer worn for 3-7 days (Actigraph GT3X) and by self-report. Associations between these exposures and measured BMI and grip strength were evaluated using linear regression. Greater time spent in light intensity activity and lower sedentary times were both associated with lower BMI. This was evident using objective measures of lower-light intensity, and both objective and self-reported measures of higher-light intensity activity. Time spent watching television was positively associated with BMI, while reading and computer use were not. Greater time spent in higher but not lower intensities of light activity (assessed objectively) was associated with greater grip strength in men but not women, while neither objectively assessed nor self-reported sedentary time was associated with grip strength. In this cross-sectional study, greater time spent in light intensity activity and lower sedentary times were associated with lower BMI. These results are consistent with the hypothesis that replacing sedentary activities with light intensity activities could lead to lower BMI levels and obesity prevalence among the population of older adults

  15. Ücretsiz mevsimsel grip aşılarını yaptıran kişilerin, ücretsiz pandemik grip aşısı karşısındaki tutum ve davranışları

    Directory of Open Access Journals (Sweden)

    Muzaffer Eskiocak

    2011-09-01

    Full Text Available Amaç: Bu çalışma, mevsimsel grip aşısına (MGA ücretsiz erişen insanların tutum ve davranışlarını, yine ücretsiz, ama çeşitli tartışmalara konu olan pandemik grip aşısı (PGA karşısındaki tutum ve davranışlarıyla karşılaştırmak amacıyla yapılmıştır. Yöntem: Araştırma tanımlayıcı tipte bir araştırmadır ve Kırklareli-Evrensekiz Sağlık Ocağı bölgesinde, Şubat,2009–Şubat,2010 tarihleri arasında yürütülmüştür. Çalışma anketi yüz-yüze görüşme yöntemiyle doldurulmuştur. Bulgular: Katılımcıların %99,2’si (n=125 kamu kurumlarının ücretsiz MGA sağlamasını destekliyordu ve tamamı (N=126 gelecek yıl da ücretsiz MGA temin edilmesini istiyordu. 2010 yılında yapılan ikinci ankette ücretsiz sağlanan PGA olanların oranının ise %4 (n=5 olduğu tespit edildi. Sonuç: Bağışıklama hizmetlerinden yararlanmada ekonomik faktörlerin çok önemli olduğu, ancak toplumun güven duygusunun zedelenmesinin, ücretsiz sağlansa da aşılamayı ciddi düzeyde engellediği saptanmıştır.Anahtar Kelimeler: Mevsimsel grip aşısı, pandemik grip aşısı Attitudes and behaviors related to free pandemic influenza vaccination of who gets vaccinated with free seasonal influenza vaccine  Objective: This study aims to compare attitudes and behaviors of the people who receive free Seasonal Influenza Vaccine (SIV with their attitudes and behaviors against Pandemic Influenza Vaccine (PIV which is also free, but controversial. Method: This study is a descriptive survey which was carried out within the service area of Evrensekiz Primary Healthcare Center (PHC in Kırklareli province and it was conducted between February 2009 and February 2010. The questionnaire has been applied by face to face interviews. Results: 99,2%of participants (n=125 supported providing free influenza vaccine by governmental organizations and all of them (N=126 wanted to get free influenza vaccine the next year

  16. Force modulation for improved conductive-mode atomic force microscopy

    NARCIS (Netherlands)

    Koelmans, W.W.; Sebastian, Abu; Despont, Michel; Pozidis, Haris

    We present an improved conductive-mode atomic force microscopy (C-AFM) method by modulating the applied loading force on the tip. Unreliable electrical contact and tip wear are the primary challenges for electrical characterization at the nanometer scale. The experiments show that force modulation

  17. Predictability of Forced Lorenz Systems

    Science.gov (United States)

    Li, Baosheng; Ding, Ruiqiang; Li, Jianping; Zhong, Quanjia

    2017-04-01

    Based on the nonlinear local Lyapunov exponent (NLLE) approach, the influences of external forcing on the predictability are studied in the Lorenz systems with constant and quasi-periodic forces in this paper. The results indicate that for the Lorenz systems with constant and quasi-periodic forces, their predictability limits increase with the forcing strength. With the same magnitude and different directions, the constant or quasi-periodic forcing shows different effects on the predictability limit in the Lorenz system, and these effects become significant with the increase of the forcing strength. Generally speaking, the positive forcing leads to a higher predictability limit than the negative forcing. Therefore, when we think about the effects of positive and negative elements and phases in the atmosphere and ocean research, the predictability problems driven by different phases should be considered separately. In addition, the influences of constant and quasi-periodic forces on the predictability are different in the Lorenz system. The effect of the constant forcing on the predictability is mainly reflected in the linear phase of error growth, while the nonlinear phase should also be considered for the situation of the quasi-periodic forcing. The predictability limit of the system under constant forcing is longer than the system under quasi-periodic forcing. These results based on simple chaotic model could provide insight into the studies of the actual atmosphere predictability.

  18. Synchronising EDML and NorthGRIP ice cores using d18O of atmospheric oxygen (d18 Oatm) and CH4 measurements over MIS5 (80-123 kyr)

    DEFF Research Database (Denmark)

    Capron, E; Landais, A; Lemieux-Dudon, B

    2010-01-01

    Water isotope records from the EPICA Dronning Maud Land (EDML) and the NorthGRIP ice cores have revealed a one to one coupling between Antarctic Isotope Maxima (AIM) and Greenland Dansgaard-Oeschger (DO) events back to 50 kyr. In order to explore if this north-south coupling is persistent over...... Marine Isotopic Stage 5 (MIS 5). a common timescale must first be constructed. Here, we present new records of delta O-18 of O-2 (delta O-18(atm)) and methane (CH4) measured in the air trapped in ice from the EDML (68-147 kyr) and NorthGRIP (70-123 kyr) ice cores. We demonstrate that, through the period...... of interest, CH4 records alone are not sufficient to construct a common gas timescale between the two cores. Millennial-scale variations of delta O-18(atm) are evidenced over MIS 5 both on the Antarctic and Greenland ice cores and are coupled to CH4 profiles to synchronise the NorthGRIP and EDML records...

  19. Modernization of African Armed Forces

    DEFF Research Database (Denmark)

    Mandrup, Thomas

    2015-01-01

    Concept paper framing the debate at the Dakar Forum Workshop on Modernization of Armed forces in Africa.......Concept paper framing the debate at the Dakar Forum Workshop on Modernization of Armed forces in Africa....

  20. Force Dynamics of Verb Complementation

    Directory of Open Access Journals (Sweden)

    Jacek Woźny

    2015-12-01

    Full Text Available Force Dynamics of Verb Complementation The concepts of motion and force are both extensively discussed in cognitive linguistics literature. But they are discussed separately. The first usually in the context of ‘motion situations’ (Talmy, Slobin, Zlatev, the other as part of the Force Dynamics framework, which was developed by Talmy. The aim of this paper is twofold: first, to argue that the concepts of force and motion should not be isolated but considered as two inseparable parts of force-motion events. The second goal is to prove that the modified Force Dynamics (force-motion framework can be used for precise characterization of the verb complementation patterns. To this end, a random sample of 50 sentences containing the verb ‘went’ is analyzed, demonstrating the differences between the categories of intensive and intransitive complementation with respect to the linguistically coded parameters of force and motion.