17 research outputs found
Quantum-enhanced micromechanical displacement sensitivity
We report on a hitherto unexplored application of squeezed light: for
quantum-enhancement of mechanical transduction sensitivity in microcavity
optomechanics. Using a toroidal silica microcavity, we experimentally
demonstrate measurement of the transduced phase modulation signal with a
sensitivity \,dB below the shot noise level. This is achieved
for resonant probing in the highly under-coupled regime, by preparing the probe
in a weak coherent state with phase squeezed vacuum states at sideband
frequencies
Cognitive and cognitive-motor interventions affecting physical functioning: A systematic review
Background
Several types of cognitive or combined cognitive-motor intervention types that might influence physical functions have been proposed in the past: training of dual-tasking abilities, and improving cognitive function through behavioral interventions or the use of computer games. The objective of this systematic review was to examine the literature regarding the use of cognitive and cognitive-motor interventions to improve physical functioning in older adults or people with neurological impairments that are similar to cognitive impairments seen in aging. The aim was to identify potentially promising methods that might be used in future intervention type studies for older adults.
Methods
A systematic search was conducted for the Medline/Premedline, PsycINFO, CINAHL and EMBASE databases. The search was focused on older adults over the age of 65. To increase the number of articles for review, we also included those discussing adult patients with neurological impairments due to trauma, as these cognitive impairments are similar to those seen in the aging population. The search was restricted to English, German and French language literature without any limitation of publication date or restriction by study design. Cognitive or cognitive-motor interventions were defined as dual-tasking, virtual reality exercise, cognitive exercise, or a combination of these.
Results
28 articles met our inclusion criteria. Three articles used an isolated cognitive rehabilitation intervention, seven articles used a dual-task intervention and 19 applied a computerized intervention. There is evidence to suggest that cognitive or motor-cognitive methods positively affects physical functioning, such as postural control, walking abilities and general functions of the upper and lower extremities, respectively. The majority of the included studies resulted in improvements of the assessed functional outcome measures.
Conclusions
The current evidence on the effectiveness of cognitive or motor-cognitive interventions to improve physical functioning in older adults or people with neurological impairments is limited. The heterogeneity of the studies published so far does not allow defining the training methodology with the greatest effectiveness. This review nevertheless provides important foundational information in order to encourage further development of novel cognitive or cognitive-motor interventions, preferably with a randomized control design. Future research that aims to examine the relation between improvements in cognitive skills and the translation to better performance on selected physical tasks should explicitly take the relation between the cognitive and physical skills into account.ISSN:1471-231
Squeezing-enhanced measurement sensitivity in a cavity optomechanical system
We determine the theoretical limits to squeezing-enhanced measurement
sensitivity of mechanical motion in a cavity optomechanical system. The motion
of a mechanical resonator is transduced onto quadrature fluctuations of a
cavity optical field and a measurement is performed on the optical field
exiting the cavity. We compare measurement sensitivities obtained with coherent
probing and quantum-enhanced probing of the mechanical motion, i.e. the
coherent probe field carries vacuum states and quadrature squeezed vacuum
states at sideband frequencies, respectively. We find that quantum-enhanced
probing provides little to no improvement in motion sensing for resonators in
the unresolved sideband regime but may significantly increase measurement
sensitivities for resonators in the resolved sideband regime
Fractures de fatigue chez l'amputé du membre inférieur pratiquant l'athlétisme en handisport : à propos de 3 cas
Squeezing-enhanced optomechanical transduction sensitivity
High-sensitivity interferometric detection of mechanical displacements has received much attention over the past decades, due to its vast field of applicability, e.g. in gravitational wave detection, cantilever-based single spin detection, and the quest to reveal quantum effects in mesoscopic mechanical systems. Following the proposal of Caves [1] we have experimentally proven the applicability of squeezed light-enhanced interferometric displacement detection in the domain of micromechanical oscillators. The technique has previously been demonstrated for table-top interferometer setups [2,3] and GW-interferometers [4,5], but to the best of our knowledge never in microcavity optomechanics
Erratum: Quantum enhanced feedback cooling of a mechanical oscillator using nonclassical light
Rehabilitation of Balance After Stroke With Multisensorial Training: A Single-Blind Randomized Controlled Study
Deep-sea hydrothermal communities in Southwestern Pacific back-arc basins (the North Fiji and Lau Basins): Composition, microdistribution and food web
International audienc