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https://www.readbyqxmd.com/read/28549053/does-incremental-positioning-weight-shifts-reduce-pressure-injuries-in-critical-care-patients
#1
Lee Ann Krapfl, Julia Langin, Caitlin A Pike, Patricia Pezzella
BACKGROUND: Incremental positioning or weight shifts are often suggested as an alternative to standard repositioning/turning in critical care patients deemed clinically unstable. OBJECTIVE: This evidence-based report card reviews whether incremental positioning and/or weight shifts reduce hospital-acquired sacral/buttocks pressure injuries in critical care patients deemed too unstable to turn. METHODS AND SEARCH STRATEGY: A scoping review of the literature was conducted for studies related to repositioning and hospital-acquired pressure injuries in high-risk, critical care patients...
May 25, 2017: Journal of Wound, Ostomy, and Continence Nursing
https://www.readbyqxmd.com/read/28539457/mechanical-evidence-that-flamingos-can-support-their-body-on-one-leg-with-little-active-muscular-force
#2
Young-Hui Chang, Lena H Ting
Flamingos (Phoenicopteridae) often stand and sleep on one leg for long periods, but it is unknown how much active muscle contractile force they use for the mechanical demands of standing on one leg: body weight support and maintaining balance. First, we demonstrated that flamingo cadavers could passively support body weight on one leg without any muscle activity while adopting a stable, unchanging, joint posture resembling that seen in live flamingos. By contrast, the cadaveric flamingo could not be stably held in a two-legged pose, suggesting a greater necessity for active muscle force to stabilize two-legged versus one-legged postures...
May 2017: Biology Letters
https://www.readbyqxmd.com/read/28537142/perceived-direction-of-gravity-and-the-body-axis-during-static-whole-body-roll-tilt-in-healthy-subjects
#3
Atsushi Tamura, Yoshiro Wada, Takuo Inui, Akihiro Shiotani
OBJECTIVE: We used the subjective visual vertical (SVV) and two different subjective visual body axis (SVBA) methods to quantify roll-tilt perception under gravity, and investigated the characteristics of these methods during static roll-tilt. In addition, we independently developed a compact device to facilitate evaluation of SVBA in different gravitational environments. METHODS: Ten male volunteers participated in this study. We created a roll-tilt environment using a flight simulator in a dark room...
May 24, 2017: Acta Oto-laryngologica
https://www.readbyqxmd.com/read/28536424/a-microfluidic-chamber-based-approach-to-map-the-shear-moduli-of-vascular-cells-and-other-soft-materials
#4
Béla Suki, Yingying Hu, Naohiko Murata, Jasmin Imsirovic, Jarred R Mondoñedo, Claudio L N de Oliveira, Niccole Schaible, Philip G Allen, Ramaswamy Krishnan, Erzsébet Bartolák-Suki
There is growing interest in quantifying vascular cell and tissue stiffness. Most measurement approaches, however, are incapable of assessing stiffness in the presence of physiological flows. We developed a microfluidic approach which allows measurement of shear modulus (G) during flow. The design included a chamber with glass windows allowing imaging with upright or inverted microscopes. Flow was controlled gravitationally to push culture media through the chamber. Fluorescent beads were conjugated to the sample surface and imaged before and during flow...
May 23, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28532880/abdominal-muscle-activity-during-breathing-in-different-postural-sets-in-healthy-subjects
#5
António Mesquita Montes, Sara Gouveia, Carlos Crasto, Cristina Argel de Melo, Paulo Carvalho, Rita Santos, João Paulo Vilas-Boas
OBJECTIVE: This study aims to evaluate the effect of different postural sets on abdominal muscle activity during breathing in healthy subjects. METHODS: Twenty-nine higher education students (20.86 ± 1.48 years; 9 males) breathed at the same rhythm (inspiration: 2 s; expiration: 4 s) in supine, standing, tripod and 4-point-kneeling positions. Surface electromyography was performed to assess the activation intensity of rectus abdominis, external oblique and transversus abdominis/internal oblique muscles during inspiration and expiration...
April 2017: Journal of Bodywork and Movement Therapies
https://www.readbyqxmd.com/read/28524688/constraints-on-the-dynamical-environments-of-supermassive-black-hole-binaries-using-pulsar-timing-arrays
#6
Stephen R Taylor, Joseph Simon, Laura Sampson
We introduce a technique for gravitational-wave analysis, where Gaussian process regression is used to emulate the strain spectrum of a stochastic background by training on population-synthesis simulations. This leads to direct Bayesian inference on astrophysical parameters. For pulsar timing arrays specifically, we interpolate over the parameter space of supermassive black-hole binary environments, including three-body stellar scattering, and evolving orbital eccentricity. We illustrate our approach on mock data, and assess the prospects for inference with data similar to the NANOGrav 9-yr data release...
May 5, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28524681/phase-shift-in-an-atom-interferometer-due-to-spacetime-curvature-across-its-wave-function
#7
Peter Asenbaum, Chris Overstreet, Tim Kovachy, Daniel D Brown, Jason M Hogan, Mark A Kasevich
Spacetime curvature induces tidal forces on the wave function of a single quantum system. Using a dual light-pulse atom interferometer, we measure a phase shift associated with such tidal forces. The macroscopic spatial superposition state in each interferometer (extending over 16 cm) acts as a nonlocal probe of the spacetime manifold. Additionally, we utilize the dual atom interferometer as a gradiometer for precise gravitational measurements.
May 5, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28524673/detecting-gravitational-wave-memory-without-parent-signals
#8
Lucy O McNeill, Eric Thrane, Paul D Lasky
Gravitational-wave memory manifests as a permanent distortion of an idealized gravitational-wave detector and arises generically from energetic astrophysical events. For example, binary black hole mergers are expected to emit memory bursts a little more than an order of magnitude smaller in strain than the oscillatory parent waves. We introduce the concept of "orphan memory": gravitational-wave memory for which there is no detectable parent signal. In particular, high-frequency gravitational-wave bursts (≳kHz) produce orphan memory in the LIGO/Virgo band...
May 5, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28521092/spontaneous-rotation-of-non-linear-pattern-formed-by-aqueous-colloidal-suspension-between-ito-electrodes-during-electrolysis-perpendicular-to-gravity
#9
Kazuya Sasaki, Shuichi Sato, Takahiro Shindo, Takeo Sakawa, Hiromu Sasaki, Masahito Sano
A colloidal fluid is found to rotate spontaneously during electrolysis when gravity acts perpendicular to the direction of an applied electric field. An aqueous dispersion containing charged colloidal particles is placed inside an O-ring sandwiched between two parallel ITO electrodes. A clip is used to hold the assembly together to prevent the liquid from leaking out. The assembly is positioned such that the electrodes stand vertically, i.e., the electric field during electrolysis points perpendicular to gravity...
May 18, 2017: Journal of Physical Chemistry. B
https://www.readbyqxmd.com/read/28513151/acoustophoretic-mobility-and-its-role-in-optimizing-acoustofluidic-separations
#10
Philip Stephen Williams, Michel Martin, Mauricio Hoyos
In the separation sciences, sample species are separated according to their physicochemical properties, the nature of the selective field, and, if present, the properties of the medium in which they are dissolved or suspended. Separations may be carried out on a continuous basis in microfluidic devices or split-flow thin channel (SPLITT) devices by selectively transporting species in a direction transverse to the direction of flow of the suspending fluid. Separation is achieved in the so-called transport mode according to relative differences in mobility of the species under the influence of the applied field...
May 17, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28502690/the-clinical-effect-of-postoperative-hyperbaric-oxygen-therapy-on-idiopathic-normal-pressure-hydrocephalus-a-retrospective-and-comparative-analysis-of-61-patients-with-ventriculoperitoneal-shunt
#11
Lin Yang, Xingdong Wang, Yuping Li, Lang Chen, Zhengcun Yan, Lei She, Jun Dong
PURPOSE: The aim of the study was to examine the clinical effect of postoperative hyperbaric oxygen (HBO) therapy on symptoms and signs in the ventriculoperitoneal (VP) shunt insertion treatment of idiopathic normal pressure hydrocephalus (iNPH). MATERIALS AND METHODS: We conducted a retrospective analysis of 61 patients treated at our institution for iNPH since 2007. Patients were stratified into 2 groups according to undergoing pure VP shunt with gravitational valves (Group 1) or combined with postoperative HBO therapy (Group 2)...
May 11, 2017: World Neurosurgery
https://www.readbyqxmd.com/read/28498710/charge-induced-force-noise-on-free-falling-test-masses-results-from-lisa-pathfinder
#12
M Armano, H Audley, G Auger, J T Baird, P Binetruy, M Born, D Bortoluzzi, N Brandt, A Bursi, M Caleno, A Cavalleri, A Cesarini, M Cruise, K Danzmann, M de Deus Silva, I Diepholz, R Dolesi, N Dunbar, L Ferraioli, V Ferroni, E D Fitzsimons, R Flatscher, M Freschi, J Gallegos, C García Marirrodriga, R Gerndt, L Gesa, F Gibert, D Giardini, R Giusteri, C Grimani, J Grzymisch, I Harrison, G Heinzel, M Hewitson, D Hollington, M Hueller, J Huesler, H Inchauspé, O Jennrich, P Jetzer, B Johlander, N Karnesis, B Kaune, C J Killow, N Korsakova, I Lloro, L Liu, J P López-Zaragoza, R Maarschalkerweerd, S Madden, D Mance, V Martín, L Martin-Polo, J Martino, F Martin-Porqueras, I Mateos, P W McNamara, J Mendes, L Mendes, A Moroni, M Nofrarias, S Paczkowski, M Perreur-Lloyd, A Petiteau, P Pivato, E Plagnol, P Prat, U Ragnit, J Ramos-Castro, J Reiche, J A Romera Perez, D I Robertson, H Rozemeijer, F Rivas, G Russano, P Sarra, A Schleicher, J Slutsky, C Sopuerta, T J Sumner, D Texier, J I Thorpe, C Trenkel, D Vetrugno, S Vitale, G Wanner, H Ward, P J Wass, D Wealthy, W J Weber, A Wittchen, C Zanoni, T Ziegler, P Zweifel
We report on electrostatic measurements made on board the European Space Agency mission LISA Pathfinder. Detailed measurements of the charge-induced electrostatic forces exerted on free-falling test masses (TMs) inside the capacitive gravitational reference sensor are the first made in a relevant environment for a space-based gravitational wave detector. Employing a combination of charge control and electric-field compensation, we show that the level of charge-induced acceleration noise on a single TM can be maintained at a level close to 1...
April 28, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28495842/the-impact-of-ocular-hemodynamics-and-intracranial-pressure-on-intraocular-pressure-during-acute-gravitational-changes
#13
Emily S Nelson, Lealem Mulugeta, Andrew Feola, Julia Raykin, Jerry G Myers, Brian C Samuels, C Ross Ethier
Exposure to microgravity causes a bulk fluid shift toward the head, with concomitant changes in blood volume/pressure, intraocular pressure (IOP), and intracranial pressure (ICP). These and other factors are thought to contribute to Visual Impairment and Intracranial Pressure syndrome, a significant health concern for astronauts, characterized by degradation of visual function and ocular anatomical changes. Here we describe a lumped-parameter numerical model to simulate volume/pressure alterations in the eye during gravitational changes...
May 11, 2017: Journal of Applied Physiology
https://www.readbyqxmd.com/read/28489082/experimental-test-of-photonic-entanglement-in-accelerated-reference-frames
#14
Matthias Fink, Ana Rodriguez-Aramendia, Johannes Handsteiner, Abdul Ziarkash, Fabian Steinlechner, Thomas Scheidl, Ivette Fuentes, Jacques Pienaar, Timothy C Ralph, Rupert Ursin
The unification of the theory of relativity and quantum mechanics is a long-standing challenge in contemporary physics. Experimental techniques in quantum optics have only recently reached the maturity required for the investigation of quantum systems under the influence of non-inertial motion, such as being held at rest in gravitational fields, or subjected to uniform accelerations. Here, we report on experiments in which a genuine quantum state of an entangled photon pair is exposed to a series of different accelerations...
May 10, 2017: Nature Communications
https://www.readbyqxmd.com/read/28479481/a-shared-biomechanical-environment-for-bone-and-posture-development-in-children
#15
Fábio A Araújo, Ana Martins, Nuno Alegrete, Laura D Howe, Raquel Lucas
BACKGROUND CONTEXT: In each specific habitual standing posture, gravitational forces determine the mechanical setting provided to skeletal structures. Bone quality and resistance to physical stress is highly determined by habitual mechanical stimulation. However, the relationship between bone properties and sagittal posture has never been studied in children. PURPOSE: To investigate the association between bone physical properties and sagittal standing postural patterns in 7-year-old children...
May 4, 2017: Spine Journal: Official Journal of the North American Spine Society
https://www.readbyqxmd.com/read/28475072/clustering-by-local-gravitation
#16
Zhiqiang Wang, Zhiwen Yu, C L Philip Chen, Jane You, Tianlong Gu, Hau-San Wong, Jun Zhang
The objective of cluster analysis is to partition a set of data points into several groups based on a suitable distance measure. We first propose a model called local gravitation among data points. In this model, each data point is viewed as an object with mass, and associated with a local resultant force (LRF) generated by its neighbors. The motivation of this paper is that there exist distinct differences between the LRFs (including magnitudes and directions) of the data points close to the cluster centers and at the boundary of the clusters...
May 2, 2017: IEEE Transactions on Cybernetics
https://www.readbyqxmd.com/read/28474927/measurement-of-a-cosmographic-distance-ratio-with-galaxy-and-cosmic-microwave-background-lensing
#17
Hironao Miyatake, Mathew S Madhavacheril, Neelima Sehgal, Anže Slosar, David N Spergel, Blake Sherwin, Alexander van Engelen
We measure the gravitational lensing shear signal around dark matter halos hosting constant mass galaxies using light sources at z∼1 (background galaxies) and at the surface of last scattering at z∼1100 (the cosmic microwave background). The galaxy shear measurement uses data from the CFHTLenS survey, and the microwave background shear measurement uses data from the Planck satellite. The ratio of shears from these cross-correlations provides a purely geometric distance measurement across the longest possible cosmological lever arm...
April 21, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28474911/black-hole-spectroscopy-with-coherent-mode-stacking
#18
Huan Yang, Kent Yagi, Jonathan Blackman, Luis Lehner, Vasileios Paschalidis, Frans Pretorius, Nicolás Yunes
The measurement of multiple ringdown modes in gravitational waves from binary black hole mergers will allow for testing the fundamental properties of black holes in general relativity and to constrain modified theories of gravity. To enhance the ability of Advanced LIGO/Virgo to perform such tasks, we propose a coherent mode stacking method to search for a chosen target mode within a collection of multiple merger events. We first rescale each signal so that the target mode in each of them has the same frequency and then sum the waveforms constructively...
April 21, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28470824/ontogenetic-shifts-of-heart-position-in-snakes
#19
Harvey B Lillywhite, Steven M Lillywhite
Heart position relative to total body length (TL) varies among snakes, with anterior hearts in arboreal species and more centrally located hearts in aquatic or ground-dwelling species. Anterior hearts decrease the cardiac work associated with cranial blood flow and minimize drops in cranial pressure and flow during head-up climbing. Here, we investigate whether heart position shifts intraspecifically during ontogenetic increases in TL. Insular Florida cottonmouth snakes, Agkistrodon conanti, are entirely ground-dwelling and have a mean heart position that is 33...
May 3, 2017: Journal of Morphology
https://www.readbyqxmd.com/read/28469380/a-new-hybrid-mgbpso-gsa-variant-for-improving-function-optimization-solution-in-search-space
#20
Narinder Singh, Sharandeep Singh, S B Singh
In this article, a newly hybrid nature-inspired approach (MGBPSO-GSA) is developed with a combination of Mean Gbest Particle Swarm Optimization (MGBPSO) and Gravitational Search Algorithm (GSA). The basic inspiration is to integrate the ability of exploitation in MGBPSO with the ability of exploration in GSA to synthesize the strength of both approaches. As a result, the presented approach has the automatic balance capability between local and global searching abilities. The performance of the hybrid approach is tested on a variety of classical functions, ie, unimodal, multimodal, and fixed-dimension multimodal functions...
2017: Evolutionary Bioinformatics Online
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