keyword
MENU ▼
Read by QxMD icon Read
search

sinusoidal rotation

keyword
https://www.readbyqxmd.com/read/28291198/-clinical-results-of-aphakia-correction-with-multifocal-intraocular-lenses
#1
G V Voronin, V R Mamikonyan, V M Sheludchenko, M N Narbut
AIM: to assess visual functions and ergonomics after bilateral versus unilateral implantation of Lentis Comfort LS-313 MF15 multifocal intraocular lenses (MIOL) in aphakic eyes. MATERIAL AND METHODS: A total of 20 patients with М LENTIS LS-313 MF15 MIOLs were followed up. Group 1 consisted of 12 patients after bilateral symmetric implantation, group 2 - of 8 patients after unilateral procedure. The following parameters were examined: uncorrected binocular visual acuity at far, near, and intermediate distances under photopic and mesopic conditions, the range of pseudoaccommodation, spatial contrast sensitivity to achromatic sinusoidal gratings, lens stability with account to its optical design, and patient satisfaction with the resultant vision...
2017: Vestnik Oftalmologii
https://www.readbyqxmd.com/read/28269379/energy-harvesting-from-human-walking-to-power-biomedical-devices-using-oscillating-generation
#2
Jose A Montoya, Dulce M Mariscal, Edwar Romero
This work summarizes the energy generation limits from walking employing a pendulum-based generation system. Self-winding wristwatches have exploited successfully this energy input technique for decades. Pendulum-based planar devices use the rotation to produce energy for inertial generators. Then the oscillations of body motion during locomotion present an opportunity to extract kinetic energy from planar generators. The sinusoidal motion of the center of gravity of the body, on the sagittal and frontal planes, and the limbs swinging are compliant with oscillating devices...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28249502/a-novel-cmos-transducer-for-giant-magnetoresistance-sensors
#3
Van Su Luong, Chih-Cheng Lu, Jing-Wen Yang, Jen-Tzong Jeng
In this work, an ASIC (application specific integrated circuits) transducer circuit for field modulated giant magnetoresistance (GMR) sensors was designed and fabricated using a 0.18-μm CMOS process. The transducer circuits consist of a frequency divider, a digital phase shifter, an instrument amplifier, and an analog mixer. These comprise a mix of analog and digital circuit techniques. The compact chip size of 1.5 mm × 1.5 mm for both analog and digital parts was achieved using the TSMC18 1P6M (1-polysilicon 6-metal) process design kit, and the characteristics of the system were simulated using an HSpice simulator...
February 2017: Review of Scientific Instruments
https://www.readbyqxmd.com/read/28227622/energy-harvesting-from-human-walking-to-power-biomedical-devices-using-oscillating-generation
#4
Jose A Montoya, Dulce M Mariscal, Edwar Romero, Jose A Montoya, Dulce M Mariscal, Edwar Romero, Dulce M Mariscal, Jose A Montoya, Edwar Romero
This work summarizes the energy generation limits from walking employing a pendulum-based generation system. Self-winding wristwatches have exploited successfully this energy input technique for decades. Pendulum-based planar devices use the rotation to produce energy for inertial generators. Then the oscillations of body motion during locomotion present an opportunity to extract kinetic energy from planar generators. The sinusoidal motion of the center of gravity of the body, on the sagittal and frontal planes, and the limbs swinging are compliant with oscillating devices...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28190505/thoracolumbar-movement-in-sound-horses-trotting-in-straight-lines-in-hand-and-on-the-lunge-and-the-relationship-with-hind-limb-symmetry-or-asymmetry
#5
L Greve, T Pfau, S Dyson
Equine movement symmetry is changed when turning, which may induce alterations in thoracolumbosacral kinematics; however, this has not previously been investigated. Our objectives were to document thoracolumbar movement in subjectively sound horses comparing straight lines with circles on both reins and to relate these observations to the objectively determined symmetry/asymmetry of hindlimb gait. Fourteen non-lame horses were assessed prospectively in a non-random, cross-sectional survey. The horses were trotted in straight lines and lunged on both reins and inertial sensor data collected at landmarks: withers, T13 and T18, L3, tubera sacrale, and left and right tubera coxae...
February 2017: Veterinary Journal
https://www.readbyqxmd.com/read/28176802/ocular-reflex-phase-during-off-vertical-axis-rotation-in-humans-is-modified-by-head-turn-on-trunk-position
#6
Samantha B Douglas, Gilles Clément, Pierre Denise, Scott J Wood
Constant velocity Off-Vertical Axis Rotation (OVAR) imposes a continuously varying orientation of the head and body relative to gravity, which generates a modulation of horizontal (conjugate and vergence), vertical, and torsional eye movements. We introduced the head-turn-on-trunk paradigm during OVAR to examine the extent to whether the modulation of these ocular reflexes is mediated by graviceptors in the head, i.e., otoliths, versus other body graviceptors. Ten human subjects were rotated in darkness about their longitudinal axis 20° off-vertical at a constant velocity of 45 and 180°/s, corresponding to 0...
February 8, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28125681/accumulation-of-inertial-sensory-information-in-the-perception-of-whole-body-yaw-rotation
#7
Alessandro Nesti, Ksander de Winkel, Heinrich H Bülthoff
While moving through the environment, our central nervous system accumulates sensory information over time to provide an estimate of our self-motion, allowing for completing crucial tasks such as maintaining balance. However, little is known on how the duration of the motion stimuli influences our performances in a self-motion discrimination task. Here we study the human ability to discriminate intensities of sinusoidal (0.5 Hz) self-rotations around the vertical axis (yaw) for four different stimulus durations (1, 2, 3 and 5 s) in darkness...
2017: PloS One
https://www.readbyqxmd.com/read/28077670/the-mammalian-efferent-vestibular-system-plays-a-crucial-role-in-vestibulo-ocular-reflex-compensation-after-unilateral-labyrinthectomy
#8
Patrick P Hübner, Serajul I Khan, Americo A Migliaccio
The α9 nicotinic acetylcholine receptor (α9-nAChR) subunit is expressed in the vestibular and auditory periphery, and its loss of function could compromise peripheral input from the predominantly-cholinergic efferent vestibular system (EVS). A recent study has shown that α9-nAChRs play an important role in short-term vestibulo-ocular reflex (VOR) adaptation. We hypothesise that α9-nAChRs could also be important for other forms of vestibular plasticity, such as that needed for VOR recovery after vestibular organ injury...
January 11, 2017: Journal of Neurophysiology
https://www.readbyqxmd.com/read/28063365/aging-reduces-the-high-frequency-and-short-term-adaptation-of-the-vestibulo-ocular-reflex-in-mice
#9
Serajul I Khan, Patrick P Hübner, Alan M Brichta, Doug W Smith, Americo A Migliaccio
Prevailing evidence indicates a relatively late life decline in human vestibulo-ocular reflex (VOR) function. Although mice are commonly used in mechanistic studies of vestibular function, it remains unclear whether aging produces a corresponding decline in VOR function in mice. We sought to determine how the baseline VOR and its short-term adaptation were affected by aging. We tested 8 young (3-month old) and 8 aged (30-month old-equivalent to a ∼80-year old human) C57BL/6 mice. We measured their VOR response to whole-body static tilts and during 0...
March 2017: Neurobiology of Aging
https://www.readbyqxmd.com/read/28047059/th-cd-207a-06-optimizing-four-dimensional-digital-tomosynthesis-acquisition-based-on-respiratory-guidance
#10
D Kim, S Lee, S Kim, S Kang, T Kim, K Kim, M Cho, D Shin, Y Noh, T Suh
PURPOSE: Patient breathing-related sorting method of projections in 4D digital tomosythesis (DTS) can be suffered from severe artifacts due to non-uniform angle distribution of projections and noncoplanar reconstructed images for each phase. In this study, we propose a method for optimally acquiring projection images in 4D DTS. METHODS: In this method every pair of projections at x-ray tube's gantry angles symmetrical with respect to the center of the range of gantry rotation is obtained at the same respiration amplitude...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/27903636/spatiotopic-coding-during-dynamic-head-tilt
#11
Kyriaki Mikellidou, Marco Turi, David C Burr
Humans maintain a stable representation of the visual world effortlessly, despite constant movements of the eyes, head, and body, across multiple planes. Whereas visual stability in the face of saccadic eye movements has been intensely researched, fewer studies have investigated retinal image transformations induced by head movements, especially in the frontal plane. Unlike head rotations in the horizontal and sagittal planes, tilting the head in the frontal plane is only partially counteracted by torsional eye movements and consequently induces a distortion of the retinal image to which we seem to be completely oblivious...
February 1, 2017: Journal of Neurophysiology
https://www.readbyqxmd.com/read/27830658/nematic-liquid-crystals-on-sinusoidal-channels-the-zigzag-instability
#12
Nuno M Silvestre, Jose M Romero-Enrique, Margarida M Telo da Gama
Substrates which are chemically or topographically patterned induce a variety of liquid crystal textures. The response of the liquid crystal to competing surface orientations, typical of patterned substrates, is determined by the anisotropy of the elastic constants and the interplay of the relevant lengths scales, such as the correlation length and the surface geometrical parameters. Transitions between different textures, usually with different symmetries, may occur under a wide range of conditions. We use the Landau-de Gennes free energy to investigate the texture of nematics in sinusoidal channels with parallel anchoring bounded by nematic-air interfaces that favour perpendicular (hometropic) anchoring...
November 10, 2016: Journal of Physics. Condensed Matter: An Institute of Physics Journal
https://www.readbyqxmd.com/read/27782689/online-4d-ultrasound-guidance-for-real-time-motion-compensation-by-mlc-tracking
#13
Svenja Ipsen, Ralf Bruder, Rick O'Brien, Paul J Keall, Achim Schweikard, Per R Poulsen
PURPOSE: With the trend in radiotherapy moving toward dose escalation and hypofractionation, the need for highly accurate targeting increases. While MLC tracking is already being successfully used for motion compensation of moving targets in the prostate, current real-time target localization methods rely on repeated x-ray imaging and implanted fiducial markers or electromagnetic transponders rather than direct target visualization. In contrast, ultrasound imaging can yield volumetric data in real-time (3D + time = 4D) without ionizing radiation...
October 2016: Medical Physics
https://www.readbyqxmd.com/read/27752252/vestibular-perceptual-thresholds-increase-above-the-age-of-40
#14
María Carolina Bermúdez Rey, Torin K Clark, Wei Wang, Tania Leeder, Yong Bian, Daniel M Merfeld
We measured vestibular perceptual thresholds in 105 healthy humans (54F/51M) ranging from 18 to 80 years of age. Direction-recognition thresholds were measured using standard methods. The motion consisted of single cycles of sinusoidal acceleration at 0.2 Hz for roll tilt and 1.0 Hz for yaw rotation about an earth-vertical axis, inter-aural earth-horizontal translation (y-translation), inferior-superior earth-vertical translation (z-translation), and roll tilt. A large subset of this population (99 of 105) also performed a modified Romberg test of standing balance...
2016: Frontiers in Neurology
https://www.readbyqxmd.com/read/27686250/dual-processing-of-visual-rotation-for-bipedal-stance-control
#15
Brian L Day, Timothy Muller, Joanna Offord, Irene Di Giulio
KEY POINTS: When standing, the gain of the body-movement response to a sinusoidally moving visual scene has been shown to get smaller with faster stimuli, possibly through changes in the apportioning of visual flow to self-motion or environment motion. We investigated whether visual-flow speed similarly influences the postural response to a discrete, unidirectional rotation of the visual scene in the frontal plane. Contrary to expectation, the evoked postural response consisted of two sequential components with opposite relationships to visual motion speed...
October 1, 2016: Journal of Physiology
https://www.readbyqxmd.com/read/27659732/cisplatin-induced-toxicity-decreases-the-mouse-vestibulo-ocular-reflex
#16
Yasumitsu Takimoto, Takao Imai, Makoto Kondo, Yukiko Hanada, Atsuhiko Uno, Yusuke Ishida, Takefumi Kamakura, Tadashi Kitahara, Hidenori Inohara, Shoichi Shimada
Cisplatin is a chemotherapeutic agent commonly used for the treatment of solid tumors, and its side-effects include vestibulotoxicity. Previous studies have reported cisplatin-induced vestibulotoxicity in various animal models, but no study has investigated in vivo mouse vestibular dysfunction after cisplatin. The aim of this study was to investigate cisplatin-induced vestibulotoxicity in C57BL/6J mice. Vestibular function was assessed by recording the vestibulo-ocular reflex (VOR). This was done during sinusoidal rotations in the horizontal plane at three frequencies (0...
November 16, 2016: Toxicology Letters
https://www.readbyqxmd.com/read/27638070/rotational-testing
#17
REVIEW
J M Furman
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...
2016: Handbook of Clinical Neurology
https://www.readbyqxmd.com/read/27579770/effects-of-bicuculline-application-on-the-somatosensory-responses-of-secondary-vestibular-neurons
#18
C Grasso, G Li Volsi, E Cataldo, D Manzoni, M Barresi
Limb somatosensory signals modify the discharge of vestibular neurons and elicit postural reflexes, which stabilize the body position. The aim of this study was to investigate the contribution of the γ-amino-butyric-acid (GABA) to the responsiveness of vestibular neurons to somatosensory inputs. The activity of 128 vestibular units was recorded in anesthetized rats in resting conditions and during sinusoidal foreleg rotation around the elbow or shoulder joints (0.026-0.625Hz, 45° peak amplitude). None of the recorded units was influenced by elbow rotation, while 40% of them responded to shoulder rotation...
October 29, 2016: Neuroscience
https://www.readbyqxmd.com/read/27560958/perceptual-stability-of-the-lissajous-figure-is-modulated-by-the-speed-of-illusory-rotation
#19
Veith A Weilnhammer, Philipp Sterzer, Guido Hesselmann
Lissajous figures represent ambiguous structure-from-motion stimuli rotating in depth and have proven to be a versatile tool to explore the cognitive and neural mechanisms underlying bistable perception. They are generated by the intersection of two sinusoids with perpendicular axes and increasing phase-shift whose frequency determines the speed of illusory 3D rotation. Recently, we found that Lissajous figures of higher shifting frequencies elicited longer perceptual phase durations and tentatively proposed a "representational momentum" account...
2016: PloS One
https://www.readbyqxmd.com/read/27489364/responses-of-non-eye-movement-central-vestibular-neurons-to-sinusoidal-yaw-rotation-in-compensated-macaques-after-unilateral-semicircular-canal-plugging
#20
Shawn D Newlands, Min Wei, David Morgan, Hongge Luan
After vestibular labyrinth injury, behavioral measures of vestibular performance recover to variable degrees (vestibular compensation). Central neuronal responses after unilateral labyrinthectomy (UL), which eliminates both afferent resting activity and sensitivity to movement, have been well-studied. However, unilateral semicircular canal plugging (UCP), which attenuates angular-velocity detection while leaving afferent resting activity intact, has not been extensively studied. The current study reports response properties of yaw-sensitive non-eye-movement rhesus macaque vestibular neurons after compensation from UCP...
October 1, 2016: Journal of Neurophysiology
keyword
keyword
101541
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"