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The Journal of Orthopaedic and Sports... Jul 2004Prospective single-group repeated-measures design.
STUDY DESIGN
Prospective single-group repeated-measures design.
OBJECTIVES
To quantify electromyographic (EMG) muscle activity of the infraspinatus, teres minor, supraspinatus, posterior deltoid, and middle deltoid during exercises commonly used to strengthen the shoulder external rotators.
BACKGROUND
Exercises to strengthen the external rotators are commonly prescribed in rehabilitation, but the amount of EMG activity of the infraspinatus, teres minor, supraspinatus, and deltoid during these exercises has not been thoroughly studied to determine which exercises would be most effective to achieve strength gains.
METHODS AND MEASURES
EMG measured using intramuscular electrodes were analyzed in 10 healthy subjects during 7 shoulder exercises: prone horizontal abduction at 100 degrees of abduction and full external rotation (ER), prone ER at 90 degrees of abduction, standing ER at 90 degrees of abduction, standing ER in the scapular plane (45 degrees abduction, 30 degrees horizontal adduction), standing ER at 0 degrees of abduction, standing ER at 0 degrees of abduction with a towel roll, and sidelying ER at 0 degrees of abduction. The peak percentage of maximal voluntary isometric contraction (MVIC) for each muscle was compared among exercises using a 1-way repeated-measures analysis of variance (P<.05).
RESULTS
EMG activity varied significantly among the 7 exercises. Sidelying ER produced the greatest amount of EMG activity for the infraspinatus (62% MVIC) and teres minor (67% MVIC). The greatest amount of activity of the supraspinatus (82% MVIC), middle deltoid (87% MVIC), and posterior deltoid (88% MVIC) was observed during prone horizontal abduction at 100 degrees with full ER.
CONCLUSIONS
Results from this study provide initial information to develop rehabilitation programs. It also provides information helpful for the design and conduct of future studies.
Topics: Adult; Electromyography; Exercise Therapy; Female; Humans; Isometric Contraction; Male; Muscle, Skeletal; Posture; Prospective Studies; Rotation; Rotator Cuff; Shoulder Joint
PubMed: 15296366
DOI: 10.2519/jospt.2004.34.7.385 -
Journal of X-ray Science and Technology 2021Manual or machine-based analysis of chest radiographs needs the images acquired with technical adequacy. Currently, the equidistance between the medial end of clavicles...
BACKGROUND
Manual or machine-based analysis of chest radiographs needs the images acquired with technical adequacy. Currently, the equidistance between the medial end of clavicles and the center of spinous processes serves as the only criterion to assess whether a frontal PA chest radiograph is taken with any rotation. However, this measurement is normally difficult to implement because there exists overlapping of anatomies within the region. Moreover, there is no way available to predict exact rotating angles even the distances were correctly measured from PA chest radiographs.
OBJECTIVE
To quantitatively assess positioning adequacy of PA chest examination, this study proposes and investigates a new method to estimate rotation angles from asymmetric projection of thoracic cage on radiographs.
METHOD
By looking into the process of radiographic projection, generalized expressions have been established to correlate rotating angles of thorax with projection difference of left and right sides of thoracic cage. A trunk phantom with different positioning angles is employed to acquire radiographs as standard reference to verify the theoretical expressions.
RESULTS
The angles estimated from asymmetric projections of thoracic cage yield good agreement with those actual rotated angles, and an approximate linear relationship exists between rotation angle and asymmetric projection of thoracic cage. Under the experimental projection settings, every degree of rotation corresponds to the width difference of two sides of thoracic cage around 13-14 pixels.
CONCLUSION
The proposed new method may be used to quantify rotating angles of chest and assess image quality for thoracic radiographic examination.
Topics: Phantoms, Imaging; Radiography; Radiography, Thoracic; Rotation; Thorax
PubMed: 34719433
DOI: 10.3233/XST-210990 -
Studies in History and Philosophy of... Aug 2021Rotation is a challenging riddle for the relationalist. In early versions of the absolute-relational debate for example, Newton's rotating bucket poured cold water on...
Rotation is a challenging riddle for the relationalist. In early versions of the absolute-relational debate for example, Newton's rotating bucket poured cold water on the relationalist position. While the parameters of the debate have changed, a more recent analysis in 1999 by Belot proclaimed rotation to be "the downfall of relationalism." In this paper, we provide a relational response to the riddle of rotation. We present a theory that, contrary to orthodoxy, can account for all rotational effects without introducing, as the absolutist does, a fixed standard of rotation. Instead, our theory posits a universal SO(3) charge that plays the role of global angular momentum and couples to inter-particle relations via terms commonly seen in standard gauge theories such as electromagnetism and the Standard Model of particle physics. Our theory makes use of an enriched form of relationalism: it adds an SO(3) structure to the traditional relational description. Our construction is made possible by the modern tools of gauge theory, which reveal a simple relational law describing rotational effects. In this way, we can save all the phenomena of Newtonian mechanics using conserved charges and relationalism. In a second paper, we will further explore the ontological and explanatory implications of the theory developed here.
Topics: Electromagnetic Phenomena; Physics; Rotation
PubMed: 34171550
DOI: 10.1016/j.shpsa.2021.05.006 -
The Journal of Physical Chemistry. B Jul 2021X-band electron paramagnetic resonance spectroscopy has been used to investigate the rotational diffusion of a stable, positively charged nitroxide...
X-band electron paramagnetic resonance spectroscopy has been used to investigate the rotational diffusion of a stable, positively charged nitroxide 4-trimethylammonium-2,2,6,6-tetramethylpiperidine-1-oxyl iodide (Cat-1) in a series of 1-alkyl-3-methylimidazolium tetrafluoroborate room-temperature ionic liquids (RTILs) having alkyl chain lengths from two to eight carbons. The rotation of Cat-1 is anisotropic with the preferential axis of rotation along the NO moiety. The Stokes-Einstein-Debye law describes the mean rotational correlation time of Cat-1, assuming that the hydrodynamic radius is smaller than the van der Waals radius of the probe. This implies that the probe rotates freely, experiencing slip boundary condition, which is solvent-dependent. The rotational correlation time of Cat-1 in RTILs can very well be fitted to a power-law functionality with a singular temperature, which suggests that the apparent activation energy of rotation exhibits non-Arrhenius behavior. Compared to the rotation of perdeuterated 2,2,6,6-tetramethyl-4-oxopiperidine-1-oxyl (pDTO), which is neutral, the rotation of Cat-1 is several times slower. The rotational anisotropy, the ratio of the rotational times of pDTO and Cat-1, and the apparent activation energy indicate the transition from a homogeneously globular structure to a spongelike structure when the alkyl chain has four carbons, which is also observed in molecular dynamics computational studies. For the first time, we have been able to show that the rotational correlation time of a solute molecule can be analyzed in terms of the Cohen-Turnbull free volume theory. The Cohen-Turnbull theory fully describes the rotation of Cat-1 in all ionic liquids in the measured temperature range.
Topics: Diffusion; Electron Spin Resonance Spectroscopy; Ionic Liquids; Rotation; Temperature
PubMed: 34197101
DOI: 10.1021/acs.jpcb.1c02471 -
Computer Assisted Surgery (Abingdon,... Dec 2022Our aim was to understand whether using different landmarks for tibial component rotation influenced articular contact pressures in a balanced total knee arthroplasty...
Our aim was to understand whether using different landmarks for tibial component rotation influenced articular contact pressures in a balanced total knee arthroplasty (TKA). Twelve patients underwent TKA (Triathlon CR, Stryker Inc., Mahwah, NJ) and contact pressures were assessed using a wireless sensor. Robotic arm assisted TKA using a functional alignment technique was performed, with balanced gaps between medial and lateral compartments. Compartment pressures were measured with the trial tibial component rotated to Akagi's line and to Insall's axis respectively. Rotating the tibial component to Akagi's line resulted in a significantly greater proportion of knees being balanced and lower contact pressures than when the tibial component was rotated to Insall's axis at 10°, 45° and 90° of flexion ( < 0.05). Medial compartment pressures were significantly increased in 10° of flexion, as were lateral compartment pressures in all positions when the tibial component was aligned to Insall's axis ( < 0.05). The mean difference in rotation observed with the two landmarks was 6.9° (range 4.1-9.1°). Rotational alignment of the tibial component using Akagi's line reduced contact pressures, improved balance and reduced the need for soft tissue release when compared with Insall's axis in robotic arm assisted TKA.
Topics: Arthroplasty, Replacement, Knee; Humans; Knee Joint; Range of Motion, Articular; Rotation; Tibia
PubMed: 35649126
DOI: 10.1080/24699322.2022.2078738 -
Physical Review. E Oct 2017Self-organizing behavior has been widely reported in both natural and artificial systems, typically distinguishing between temporal organization (synchronization) and...
Self-organizing behavior has been widely reported in both natural and artificial systems, typically distinguishing between temporal organization (synchronization) and spatial organization (swarming). Swarming has been experimentally observed in systems of magnetotactic bacteria under the action of external magnetic fields. Here we present a model of ensembles of magnetotactic bacteria in which hydrodynamic interactions lead to temporal synchronization in addition to the swarming. After a period of stabilization during which the bacteria form a quasiregular hexagonal lattice structure, the entire swarm begins to rotate in a direction opposite to the direction of the rotation of the magnetic field. We thus illustrate an emergent mechanism of macroscopic motion arising from the synchronized microscopic rotations of hydrodynamically interacting bacteria, reminiscent of the recently proposed concept of swarmalators.
Topics: Bacterial Physiological Phenomena; Computer Simulation; Hydrodynamics; Magnetic Fields; Models, Biological; Movement; Periodicity; Rotation
PubMed: 29347499
DOI: 10.1103/PhysRevE.96.042408 -
Handbook of Clinical Neurology 2016The natural stimulus for the semicircular canals is rotation of the head, which also might stimulate the otolith organs. Vestibular stimulation usually induces eye... (Review)
Review
The natural stimulus for the semicircular canals is rotation of the head, which also might stimulate the otolith organs. Vestibular stimulation usually induces eye movements via the vestibulo-ocular reflex (VOR). The orientation of the subject with respect to the axis of rotation and the orientation of the axis of rotation with respect to gravity together determine which labyrinthine receptors are stimulated for particular motion trajectories. Rotational testing usually includes the measurement of eye movements via a video system but might use a subject's perception of motion. The most common types of rotational testing are whole-body computer-controlled sinusoidal or trapezoidal stimuli during earth-vertical axis rotation (EVAR), which stimulates primarily the horizontal semicircular canals bilaterally. Recently, manual impulsive rotations, known as head impulse testing (HIT), have been developed to assess individual horizontal semicircular canals. Most types of rotational stimuli are not used routinely in the clinical setting but may be used in selected research environments. This chapter will discuss clinically relevant rotational stimuli and several types of rotational testing that are used primarily in research settings.
Topics: Eye Movements; Humans; Physical Stimulation; Reflex, Vestibulo-Ocular; Rotation
PubMed: 27638070
DOI: 10.1016/B978-0-444-63437-5.00012-1 -
PsyCh Journal Dec 2021The aim of this study was to determine if the ability to rotate mental imagery influenced the comprehension of graphs in economics. A sample of 140 Business...
The aim of this study was to determine if the ability to rotate mental imagery influenced the comprehension of graphs in economics. A sample of 140 Business Administration undergraduates familiar with economic analysis using graphs were administered the Measure of the Ability to Rotate Mental Images (MARMI). Moreover, participants completed an ad hoc graph comprehension test consisting of six exercises of increasing difficulty with graphs developing the IS-LM model described in conventional macroeconomic textbooks. Both the ability to rotate mental imagery and graph complexity (the number of quadrants in each graph) were found to significantly influence the number of correct graph comprehension responses.
Topics: Comprehension; Humans; Imagery, Psychotherapy; Rotation
PubMed: 34704373
DOI: 10.1002/pchj.494 -
BMC Anesthesiology Aug 2023Nasal intubation using a fiberoptic scope is a useful technique. In clinical practice, we have experienced difficulty in advancing the endotracheal tube (ETT) over the... (Observational Study)
Observational Study
BACKGROUND
Nasal intubation using a fiberoptic scope is a useful technique. In clinical practice, we have experienced difficulty in advancing the endotracheal tube (ETT) over the fiberoptic scope because of resistance to the passage of the ETT against rotation in the nasal cavity, when it gets hung up on structures of the laryngeal inlet. Several maneuvers have been proposed to overcome this difficulty. The gap between the tip of the ETT and the fiberoptic scope can be reduced using a thicker fiberoptic scope and a thinner ETT. Moreover, simultaneous rotation of the fiberoptic scope and ETT could lead to successful intubation by reducing impingement on the ETT. However, the discrepancy between these rotation angles is unclear. This observational prospective study aimed to investigate the discrepancy in the rotation angle between the ETT and fiberoptic scope during nasal intubation.
METHODS
The patients (aged 20-80 years) who underwent nasal intubation for oral and maxillofacial surgery participated in three sizes of preformed nasal ETT and were intubated using a fiberoptic scope. They were divided into three groups; the ETT internal diameter (ID) 6.5 mm (6.5 group), ID 7.0 mm (7.0 group), and ID 7.5 mm (7.5 group). The ETT was then inserted through the nasal cavity into the pharynx. After the fiberoptic scope was advanced through the ETT above the glottis, simultaneous rotation by both the proximal end of the fiberoptic scope and ETT was performed in 90° and 180° in both right (clockwise) and left (counterclockwise) directions, and the rotation angle at the distal end of the ETT was monitored using a video laryngoscope (Pentax-AWS).
RESULTS
A total of 39 patients were included in the study. When both the proximal end of the fiberscope and ETT were simultaneously rotated by 90°, in the 6.5 group (n = 13), the distal end of the ETT rotated by 47.8 ± 1.5°. In the 7.0 °group (n = 13), the distal end of the ETT rotated by 45.5 ± 1.0°. In the 7.5 group (n = 13), the distal end of the ETT rotated by 39.9 ± 1.0°. When the proximal end of the fiberscope and ETT were rotated by 180°, in the 6.5 group, the distal end of the ETT rotated by 166.2 ± 2.5°. In the 7.0 group, the distal end of the ETT rotated by 145.7 ± 2.2°. In the 7.5 group, the distal end of the ETT rotated by 115.1 ± 2.0°. All rotation angles in the distal end of the ETT were significantly lower than those in both the proximal end of the fiberscope and ETT (p < 0.05). Rotating right by 180° was significantly different among the three groups (p < 0.05), although rotating right by 90° was not significantly different. Similar results were obtained for the left rotation.
CONCLUSION
Simultaneous rotation by the proximal end of the ETT and fiberscope above the glottis for the nasal approach induced significant differences in the distal end of the ETT. The larger tube lagged by the resistance of the nasal passages during rotation. Therefore, the ETT does not rotate as much as the rotation angle.
TRIAL REGISTRATION
This prospective observational study was conducted after receiving approval from the Ethics Review Board of Kyushu University Hospital (Approval No. 30-447).
Topics: Humans; Intubation, Intratracheal; Larynx; Nasal Cavity; Prospective Studies; Rotation; Young Adult; Adult; Middle Aged; Aged; Aged, 80 and over
PubMed: 37568085
DOI: 10.1186/s12871-023-02225-7 -
Electrophoresis Mar 2019Cell rotation is widely required in various fields as an important technique for single cell manipulation. Usually, the electro-rotational manipulation of single cells...
Cell rotation is widely required in various fields as an important technique for single cell manipulation. Usually, the electro-rotational manipulation of single cells by dielectrophoresis technologies requires at least three electrodes to generate rotating electric fields which induce cells to rotate. Here, we present a novel microfluidic chip capable of rotating single cell using only two planar electrodes by taking polarized cells as the extra electrodes with phase-shifted signal. To demonstrate this idea, we configured two parallel and planar electrodes as basic dielectrophoresis elements and placed trenches above these electrodes to attract cells, which were in turn polarized to be electrodes. Through simulation, we confirmed the functional structure of the device works well to generate proper rotating electric fields for cell rotation. Through experiment, we successfully demonstrated controlled electro-rotation of HeLa and HepaRG cells. The novel electro-rotation mechanism not only simplifies the micro-device structure but also reduces the complexity of single cell rotation operation which will be a benefit to the potential users.
Topics: Electrochemical Techniques; Electrodes; Equipment Design; HeLa Cells; Humans; Microfluidic Analytical Techniques; Rotation; Single-Cell Analysis
PubMed: 30350868
DOI: 10.1002/elps.201800360