The Uniformly Accelerated Reference Frame
ERIC Educational Resources Information Center
Hamilton, J. Dwayne
1978-01-01
The observations that would be made by a uniformly accelerated observer, including the observer's event horizon, the variation of clock rates with position, and the effects of following a freely falling object are considered in detail. (SL)
Experiments Using Cell Phones in Physics Classroom Education: The Computer-Aided g Determination
NASA Astrophysics Data System (ADS)
Vogt, Patrik; Kuhn, Jochen; Müller, Sebastian
2011-09-01
This paper continues the collection of experiments that describe the use of cell phones as experimental tools in physics classroom education.1-4 We describe a computer-aided determination of the free-fall acceleration g using the acoustical Doppler effect. The Doppler shift is a function of the speed of the source. Since a free-falling objects speed is changing linearly with time, the Doppler shift is also changing with time. It is possible to measure this shift using software that is both easy to use and readily available. Students will use the time-dependency of the Doppler shift to experimentally determine the acceleration due to gravity by using a cell phone as a freely falling object emitting a sound with constant frequency.
Energy and information near black hole horizons
DOE Office of Scientific and Technical Information (OSTI.GOV)
Freivogel, Ben, E-mail: benfreivogel@gmail.com
2014-07-01
The central challenge in trying to resolve the firewall paradox is to identify excitations in the near-horizon zone of a black hole that can carry information without injuring a freely falling observer. By analyzing the problem from the point of view of a freely falling observer, I arrive at a simple proposal for the degrees of freedom that carry information out of the black hole. An infalling observer experiences the information-carrying modes as ingoing, negative energy excitations of the quantum fields. In these states, freely falling observers who fall in from infinity do not encounter a firewall, but freely fallingmore » observers who begin their free fall from a location close to the horizon are ''frozen'' by a flux of negative energy. When the black hole is ''mined,'' the number of information-carrying modes increases, increasing the negative energy flux in the infalling frame without violating the equivalence principle. Finally, I point out a loophole in recent arguments that an infalling observer must detect a violation of unitarity, effective field theory, or free infall.« less
Science 101: How Do People Design Safe Amusement Park Rides?
ERIC Educational Resources Information Center
Robertson, Bill
2015-01-01
To address the question of how people design safe amusement park rides, Bill Robertson focuses on the factors designers must consider so that human bodies don't experience too large an acceleration (any change in speed and/or direction) or "g-force" (the acceleration an object undergoes while freely falling, with no air resistance, under…
Can MOND type hypotheses be tested in a free fall laboratory environment?
NASA Astrophysics Data System (ADS)
Das, Saurya; Patitsas, S. N.
2013-05-01
The extremely small accelerations of objects required for the onset of modified Newtonian dynamics, or modified Newtonian dynamics (MOND), makes testing the hypothesis in conventional terrestrial laboratories virtually impossible. This is due to the large background acceleration of Earth, which is transmitted to the acceleration of test objects within an apparatus. We show, however, that it may be possible to test MOND-type hypotheses with experiments using a conventional apparatus capable of tracking very small accelerations of its components but performed in locally inertial frames such as artificial satellites and other freely falling laboratories. For example, experiments involving an optical interferometer or a torsion balance in these laboratories would show nonlinear dynamics and displacement amplitudes larger than expected. These experiments may also be able to test potential violations of the strong equivalence principle by MOND and to distinguish between its two possible interpretations (modified inertia and modified gravity).
Numerical simulation of h-adaptive immersed boundary method for freely falling disks
NASA Astrophysics Data System (ADS)
Zhang, Pan; Xia, Zhenhua; Cai, Qingdong
2018-05-01
In this work, a freely falling disk with aspect ratio 1/10 is directly simulated by using an adaptive numerical model implemented on a parallel computation framework JASMIN. The adaptive numerical model is a combination of the h-adaptive mesh refinement technique and the implicit immersed boundary method (IBM). Our numerical results agree well with the experimental results in all of the six degrees of freedom of the disk. Furthermore, very similar vortex structures observed in the experiment were also obtained.
a Portable Apparatus for Absolute Measurements of the Earth's Gravity.
NASA Astrophysics Data System (ADS)
Zumberge, Mark Andrew
We have developed a new, portable apparatus for making absolute measurements of the acceleration due to the earth's gravity. We use the method of interferometrically determining the acceleration of a freely falling corner -cube prism. The falling object is surrounded by a chamber which is driven vertically inside a fixed vacuum chamber. This falling chamber is servoed to track the falling corner -cube to shield it from drag due to background gas. In addition, the drag-free falling chamber removes the need for a magnetic release, shields the falling object from electrostatic forces, and provides a means of both gently arresting the falling object and quickly returning it to its start position, to allow rapid acquisition of data. A synthesized long period isolation device reduces the noise due to seismic oscillations. A new type of Zeeman laser is used as the light source in the interferometer, and is compared with the wavelength of an iodine stabilized laser. The times of occurrence of 45 interference fringes are measured to within 0.2 nsec over a 20 cm drop and are fit to a quadratic by an on-line minicomputer. 150 drops can be made in ten minutes resulting in a value of g having a precision of 3 to 6 parts in 10('9). Systematic errors have been determined to be less than 5 parts in 10('9) through extensive tests. Three months of gravity data have been obtained with a reproducibility ranging from 5 to 10 parts in 10('9). The apparatus has been designed to be easily portable. Field measurements are planned for the immediate future. An accuracy of 6 parts in 10('9) corresponds to a height sensitivity of 2 cm. Vertical motions in the earth's crust and tectonic density changes that may precede earthquakes are to be investigated using this apparatus.
A Photographic Study of Freezing of Water Droplets Falling Freely in Air
NASA Technical Reports Server (NTRS)
Dorsch, Robert G.; Levine, Joseph
1952-01-01
A photographic technique for investigating water droplets of diameter less than 200 microns falling freely in air at temperatures between 0 C and -50 C has been devised and used to determine: (i) The shape of frozen droplets (2) The occurrence of collisions of partly frozen or of frozen and liquid droplets (3) The statistics on the freezing temperatures of individual free-falling droplets A considerable number of droplets were found to have a nonspherical shape after freezing because of various protuberances and frost growth, and droplet aggregates formed by collision. The observed frequency of collision of partly frozen droplets showed good order of magnitude agreement with the frequency computed from theoretical collection efficiencies. The freezing temperature statistics indicated a general similarity of the data to those obtained for droplets frozen on a metallic surface in previous experiments.
For over twenty-five years Antony Williams has been delivering presentations to chemists about how to utilize freely available websites to help create an online presence. Over the years he has presented on LinkedIn for a professional CV, ResearchGate for sharing papers and resear...
Safety yoke would protect construction workers from falling
NASA Technical Reports Server (NTRS)
Goforth, O. H.
1967-01-01
Simple dismountable yoke protects construction workers on narrow steel I beams at high levels. The yoke engages the upper flat of the I beam and slides freely along it to permit freedom of movement to the worker while limiting his ability to fall by a harness attached to the yoke.
A simple demonstration when studying the equivalence principle
NASA Astrophysics Data System (ADS)
Mayer, Valery; Varaksina, Ekaterina
2016-06-01
The paper proposes a lecture experiment that can be demonstrated when studying the equivalence principle formulated by Albert Einstein. The demonstration consists of creating stroboscopic photographs of a ball moving along a parabola in Earth's gravitational field. In the first experiment, a camera is stationary relative to Earth's surface. In the second, the camera falls freely downwards with the ball, allowing students to see that the ball moves uniformly and rectilinearly relative to the frame of reference of the freely falling camera. The equivalence principle explains this result, as it is always possible to propose an inertial frame of reference for a small region of a gravitational field, where space-time effects of curvature are negligible.
Tidal Forces in Dyonic Reissner-Nördstrom Black Hole
NASA Astrophysics Data System (ADS)
Sharif, M.; Kousar, Lubna
2018-03-01
This paper investigates the tidal as well as magnetic charge effects produced in dyonic Reissner-Nordström black hole. We evaluate Newtonian radial acceleration using radial geodesics for freely falling test particles. We establish system of equations governing radial and angular tidal forces using geodesic deviation equation and discuss their solutions for bodies falling freely towards this black hole. The radial tidal force turns out to be compressing outside the event horizon whereas the angular tidal force changes sign between event and Cauchy horizons unlike Schwarzschild black hole. The radial geodesic component starts decreasing in dyonic Reissner-Nordström black hole unlike Schwarzschild case. We conclude that magnetic charge strongly affects the radial as well as angular components of tidal force.
A Person Stands on a Balance in an Elevator: What Happens When the Elevator Starts to Fall?
ERIC Educational Resources Information Center
Balukovic, Jasmina; Slisko, Josip; Cruz, Adrián Corona
2018-01-01
Physics textbook authors commonly introduce the concept of weightlessness (apparent or real) through a "thought experiment" in which a person weighs herself or himself in an elevator. When the elevator falls freely, the spring balance should show zero weight. There is an unresolved controversy about how this "zero reading"…
46 CFR 163.003-21 - Approval tests.
Code of Federal Regulations, 2012 CFR
2012-10-01
... structure that would prevent it from falling freely, and where it can hang to its full length vertically... that the grooves form a diamond pattern covering the stepping surface. The centers of all parallel...
46 CFR 163.003-21 - Approval tests.
Code of Federal Regulations, 2011 CFR
2011-10-01
... structure that would prevent it from falling freely, and where it can hang to its full length vertically... that the grooves form a diamond pattern covering the stepping surface. The centers of all parallel...
46 CFR 163.003-21 - Approval tests.
Code of Federal Regulations, 2013 CFR
2013-10-01
... structure that would prevent it from falling freely, and where it can hang to its full length vertically... that the grooves form a diamond pattern covering the stepping surface. The centers of all parallel...
46 CFR 163.003-21 - Approval tests.
Code of Federal Regulations, 2014 CFR
2014-10-01
... structure that would prevent it from falling freely, and where it can hang to its full length vertically... that the grooves form a diamond pattern covering the stepping surface. The centers of all parallel...
Surface Oscillations of a Free-Falling Droplet of an Ideal Fluid
NASA Astrophysics Data System (ADS)
Kistovich, A. V.; Chashechkin, Yu. D.
2018-03-01
According to observations, drops freely falling in the air under the action of gravity are deformed and oscillate in a wide range of frequencies and scales. A technique for calculating surface axisymmetric oscillations of a deformed droplet in the linear approximation under the assumption that the amplitude and wavelength are small when compared to the droplet diameter is proposed. The basic form of an axisymmetric droplet is chosen from observations. The calculation results for surface oscillations agree with recorded data on the varying shape of water droplets falling in the air.
NASA Astrophysics Data System (ADS)
Mathai, Varghese; Zhu, Xiaojue; Sun, Chao; Lohse, Detlef
2017-08-01
In this Letter, we study the motion and wake patterns of freely rising and falling cylinders in quiescent fluid. We show that the amplitude of oscillation and the overall system dynamics are intricately linked to two parameters: the particle's mass density relative to the fluid m*≡ρp/ρf and its relative moment of inertia I*≡Ip/If. This supersedes the current understanding that a critical mass density (m*≈0.54 ) alone triggers the sudden onset of vigorous vibrations. Using over 144 combinations of m* and I*, we comprehensively map out the parameter space covering very heavy (m*>10 ) to very buoyant (m*<0.1 ) particles. The entire data collapse into two scaling regimes demarcated by a transitional Strouhal number Stt≈0.17 . Stt separates a mass-dominated regime from a regime dominated by the particle's moment of inertia. A shift from one regime to the other also marks a gradual transition in the wake-shedding pattern: from the classical two-single (2 S ) vortex mode to a two-pair (2 P ) vortex mode. Thus, autorotation can have a significant influence on the trajectories and wakes of freely rising isotropic bodies.
Motion transitions of falling plates via quasisteady aerodynamics.
Hu, Ruifeng; Wang, Lifeng
2014-07-01
In this paper, we study the dynamics of freely falling plates based on the Kirchhoff equation and the quasisteady aerodynamic model. Motion transitions among fluttering, tumbling along a cusp-like trajectory, irregular, and tumbling along a straight trajectory are obtained by solving the dynamical equations. Phase diagrams spanning between the nondimensional moment of inertia and aerodynamic coefficients or aspect ratio are built to identify regimes for these falling styles. We also investigate the stability of fixed points and bifurcation scenarios. It is found that the transitions are all heteroclinic bifurcations and the influence of the fixed-point stability is local.
Results of Two Free-fall Experiments on Flutter of Thin Unswept Wings in the Transonic Speed Range
NASA Technical Reports Server (NTRS)
Lauten, William T , Jr; Nelson, Herbert C
1957-01-01
Results of four thin, unswept, flutter airfoils attached to two freely falling bodies are reported. Two airfoils fluttered at a Mach number of 0.85, a third airfoil fluttered at a Mach number of 1.03, and a fourth fluttered at a Mach number of 1.07. Results of calculations of flutter speed using incompressible and compressible air-force coefficients, including a Mach number of 1.0, are presented.
NASA Technical Reports Server (NTRS)
Dufresne, Eugene R.
1987-01-01
Liquids, such as juices, milk, molten metal and the like are concentrated by forming uniformly-sized, small droplets in a precision droplet forming assembly and deploying the droplets in free fall downwardly as a central column within an evacuated column with cool walls. A portion of the solvent evaporates. The vapor flows to the wall, condenses, and usually flows down the wall as a film to condensate collector and drain. The vertical column of freely falling droplets enters the splash guard. The condensate can be collected, sent to other towers or recycled.
Machado, S; Cunha, M; Portella, C E; Silva, J G; Velasques, B; Bastos, V H; Basile, L; Cagy, M; Piedade, R A; Ribeiro, P
A fundamental aspect of planning future actions is the performance and control of motor tasks. This behaviour is done through sensory-motor integration. To explain the electrophysiological mechanisms in the cortex (modifications to the alpha band) that are involved in anticipatory actions when individuals have to catch a free-falling object. The sample was made up of 20 healthy subjects of both sexes (11 males and 9 females) with ages ranging between 25 and 40 years (32.5 +/- 7.5) who were free of mental or physical diseases (previous medical history); the subjects were right-handed (Edinburgh Inventory) and were not taking any psychoactive or psychotropic substances at the time of the study. The experiment consisted in a task in which subjects had to catch freely falling objects. The experiment was made up of six blocks of 15 tests, each of which lasted 2 minutes and 30 seconds, with a break of one minute between blocks. Data were captured by means of a quantitative electroencephalogram two seconds before and two seconds after each ball was dropped. An interaction of the factors moment and position was only observed for the right parietooccipital cortex, in the combination of electrodes P4-O2. These findings suggest that the right parietooccipital cortex plays an important role in increasing expectation and swiftness in the processes of preparing for a motor task.
Many of us nowadays invest significant amounts of time in sharing our activities and opinions with friends and family via social networking tools such as Facebook, Twitter or other related websites. However, despite the availability of many other platforms for scientists to conne...
Code of Federal Regulations, 2013 CFR
2013-10-01
... (b) of this section, on a rigid pendulum as shown in Figure 22 so that the head's midsagittal plane is vertical and coincides with the plane of motion of the pendulum's longitudinal axis. ER02JN11.011 (4) Release the pendulum and allow it to fall freely from a height such that the tangential velocity...
Code of Federal Regulations, 2011 CFR
2011-10-01
... (b) of this section, on a rigid pendulum as shown in Figure 22 so that the head's midsagittal plane is vertical and coincides with the plane of motion of the pendulum's longitudinal axis. EC01AU91.165 (4) Release the pendulum and allow it to fall freely from a height such that the tangential velocity...
Code of Federal Regulations, 2012 CFR
2012-10-01
... (b) of this section, on a rigid pendulum as shown in Figure 22 so that the head's midsagittal plane is vertical and coincides with the plane of motion of the pendulum's longitudinal axis. ER02JN11.011 (4) Release the pendulum and allow it to fall freely from a height such that the tangential velocity...
Code of Federal Regulations, 2010 CFR
2010-10-01
... (b) of this section, on a rigid pendulum as shown in Figure 22 so that the head's midsagittal plane is vertical and coincides with the plane of motion of the pendulum's longitudinal axis. EC01AU91.165 (4) Release the pendulum and allow it to fall freely from a height such that the tangential velocity...
49 CFR 572.183 - Neck assembly.
Code of Federal Regulations, 2013 CFR
2013-10-01
... subpart E pendulum test fixture as shown in Figure U2-A in appendix A to this subpart, so that the... pendulum longitudinal centerline shown in Figure U2-A. Torque the half-spherical screws (175-2004) located... equivalent; (3) Release the pendulum from a height sufficient to allow it to fall freely to achieve an impact...
49 CFR 572.183 - Neck assembly.
Code of Federal Regulations, 2012 CFR
2012-10-01
... subpart E pendulum test fixture as shown in Figure U2-A in appendix A to this subpart, so that the... pendulum longitudinal centerline shown in Figure U2-A. Torque the half-spherical screws (175-2004) located... equivalent; (3) Release the pendulum from a height sufficient to allow it to fall freely to achieve an impact...
49 CFR 572.183 - Neck assembly.
Code of Federal Regulations, 2010 CFR
2010-10-01
... subpart E pendulum test fixture as shown in Figure U2-A in appendix A to this subpart, so that the... pendulum longitudinal centerline shown in Figure U2-A. Torque the half-spherical screws (175-2004) located... equivalent; (3) Release the pendulum from a height sufficient to allow it to fall freely to achieve an impact...
49 CFR 572.183 - Neck assembly.
Code of Federal Regulations, 2011 CFR
2011-10-01
... subpart E pendulum test fixture as shown in Figure U2-A in appendix A to this subpart, so that the... pendulum longitudinal centerline shown in Figure U2-A. Torque the half-spherical screws (175-2004) located... equivalent; (3) Release the pendulum from a height sufficient to allow it to fall freely to achieve an impact...
Code of Federal Regulations, 2014 CFR
2014-10-01
... (b) of this section, on a rigid pendulum as shown in Figure 22 so that the head's midsagittal plane is vertical and coincides with the plane of motion of the pendulum's longitudinal axis. ER02JN11.011 (4) Release the pendulum and allow it to fall freely from a height such that the tangential velocity...
49 CFR 572.183 - Neck assembly.
Code of Federal Regulations, 2014 CFR
2014-10-01
... subpart E pendulum test fixture as shown in Figure U2-A in appendix A to this subpart, so that the... pendulum longitudinal centerline shown in Figure U2-A. Torque the half-spherical screws (175-2004) located... equivalent; (3) Release the pendulum from a height sufficient to allow it to fall freely to achieve an impact...
Quantum Computing: Selected Internet Resources for Librarians, Researchers, and the Casually Curious
ERIC Educational Resources Information Center
Cirasella, Jill
2009-01-01
This article presents an annotated selection of the most important and informative Internet resources for learning about quantum computing, finding quantum computing literature, and tracking quantum computing news. All of the quantum computing resources described in this article are freely available, English-language web sites that fall into one…
NASA Astrophysics Data System (ADS)
Rothleitner, Christian; Francis, Olivier
2014-04-01
An original setup is presented to measure the Newtonian Constant of Gravitation G. It is based on the same principle as used in ballistic absolute gravimeters. The differential acceleration of three simultaneously freely falling test masses is measured in order to determine G. In this paper, a description of the experimental setup is presented. A detailed uncertainty budget estimates the relative uncertainty to be of the order of 5.3 × 10-4, however with some improvements a relative uncertainty in G of one part in 104 could be feasible.
Impulse Measurement Using an Arduíno
ERIC Educational Resources Information Center
Espindola, P. R.; Cena, C. R.; Alves, D. C. B.; Bozano, D. F.; Goncalves, A. M. B.
2018-01-01
In this paper, we propose a simple experimental apparatus that can measure the force variation over time to study the impulse-momentum theorem. In this proposal, a body attached to a rubber string falls freely from rest until it stretches and changes the linear momentum. During that process the force due to the tension on the rubber string is…
Going nuts: Measuring free-fall acceleration by analyzing the sound of falling metal pieces
NASA Astrophysics Data System (ADS)
Kuhn, Jochen; Vogt, Patrik; Theilmann, Florian
2016-03-01
Galilei presented the kinematics of a one-dimensional accelerated motion with ease and in terms of elegant geometry. Moreover, he believed, "Philosophy [i.e. physics] is written in this grand book—I mean the universe—which stands continually open to our gaze, but it cannot be understood unless one first learns to comprehend the language and interpret the characters in which it is written. It is written in the language of mathematics, and its characters are triangles, circles, and other geometrical figures, without which it is humanly impossible to understand a single word of it." In classroom practice, however, it can be difficult to reveal this mathematical heart of nature; free fall and other accelerated motions often get obscured by friction or other sources of errors. In this paper, we introduce a method of analyzing free-fall motion indirectly by evaluating the noise of freely falling metal pieces. The method connects a deeper understanding of the mathematical structure of accelerated motion with the possibility to derive a numerical value for the free-fall acceleration g.
FRAT-up, a Web-based Fall-Risk Assessment Tool for Elderly People Living in the Community
Cattelani, Luca; Palumbo, Pierpaolo; Palmerini, Luca; Bandinelli, Stefania; Becker, Clemens; Chiari, Lorenzo
2015-01-01
Background About 30% of people over 65 are subject to at least one unintentional fall a year. Fall prevention protocols and interventions can decrease the number of falls. To be effective, a prevention strategy requires a prior step to evaluate the fall risk of the subjects. Despite extensive research, existing assessment tools for fall risk have been insufficient for predicting falls. Objective The goal of this study is to present a novel web-based fall-risk assessment tool (FRAT-up) and to evaluate its accuracy in predicting falls, within a context of community-dwelling persons aged 65 and up. Methods FRAT-up is based on the assumption that a subject’s fall risk is given by the contribution of their exposure to each of the known fall-risk factors. Many scientific studies have investigated the relationship between falls and risk factors. The majority of these studies adopted statistical approaches, usually providing quantitative information such as odds ratios. FRAT-up exploits these numerical results to compute how each single factor contributes to the overall fall risk. FRAT-up is based on a formal ontology that enlists a number of known risk factors, together with quantitative findings in terms of odds ratios. From such information, an automatic algorithm generates a rule-based probabilistic logic program, that is, a set of rules for each risk factor. The rule-based program takes the health profile of the subject (in terms of exposure to the risk factors) and computes the fall risk. A Web-based interface allows users to input health profiles and to visualize the risk assessment for the given subject. FRAT-up has been evaluated on the InCHIANTI Study dataset, a representative population-based study of older persons living in the Chianti area (Tuscany, Italy). We compared reported falls with predicted ones and computed performance indicators. Results The obtained area under curve of the receiver operating characteristic was 0.642 (95% CI 0.614-0.669), while the Brier score was 0.174. The Hosmer-Lemeshow test indicated statistical significance of miscalibration. Conclusions FRAT-up is a web-based tool for evaluating the fall risk of people aged 65 or up living in the community. Validation results of fall risks computed by FRAT-up show that its performance is comparable to externally validated state-of-the-art tools. A prototype is freely available through a web-based interface. Trial Registration ClinicalTrials.gov NCT01331512 (The InChianti Follow-Up Study); http://clinicaltrials.gov/show/NCT01331512 (Archived by WebCite at http://www.webcitation.org/6UDrrRuaR). PMID:25693419
Bose-Einstein condensation in microgravity.
van Zoest, T; Gaaloul, N; Singh, Y; Ahlers, H; Herr, W; Seidel, S T; Ertmer, W; Rasel, E; Eckart, M; Kajari, E; Arnold, S; Nandi, G; Schleich, W P; Walser, R; Vogel, A; Sengstock, K; Bongs, K; Lewoczko-Adamczyk, W; Schiemangk, M; Schuldt, T; Peters, A; Könemann, T; Müntinga, H; Lämmerzahl, C; Dittus, H; Steinmetz, T; Hänsch, T W; Reichel, J
2010-06-18
Albert Einstein's insight that it is impossible to distinguish a local experiment in a "freely falling elevator" from one in free space led to the development of the theory of general relativity. The wave nature of matter manifests itself in a striking way in Bose-Einstein condensates, where millions of atoms lose their identity and can be described by a single macroscopic wave function. We combine these two topics and report the preparation and observation of a Bose-Einstein condensate during free fall in a 146-meter-tall evacuated drop tower. During the expansion over 1 second, the atoms form a giant coherent matter wave that is delocalized on a millimeter scale, which represents a promising source for matter-wave interferometry to test the universality of free fall with quantum matter.
49 CFR 572.187 - Lumbar spine.
Code of Federal Regulations, 2013 CFR
2013-10-01
...-headform assembly to the Part 572 pendulum test fixture per procedure in § 572.183(b)(2) and as shown in... assembly (175-5506) to 50 ±5 in-lb; (3) Release the pendulum from a height sufficient to allow it to fall freely to achieve an impact velocity of 6.05 ±0.1 m/s measured at the center of the pendulum...
49 CFR 572.187 - Lumbar spine.
Code of Federal Regulations, 2012 CFR
2012-10-01
...-headform assembly to the Part 572 pendulum test fixture per procedure in § 572.183(b)(2) and as shown in... assembly (175-5506) to 50 ±5 in-lb; (3) Release the pendulum from a height sufficient to allow it to fall freely to achieve an impact velocity of 6.05 ±0.1 m/s measured at the center of the pendulum...
49 CFR 572.187 - Lumbar spine.
Code of Federal Regulations, 2011 CFR
2011-10-01
...-headform assembly to the Part 572 pendulum test fixture per procedure in § 572.183(b)(2) and as shown in... assembly (175-5506) to 50 ± 5 in-lb; (3) Release the pendulum from a height sufficient to allow it to fall freely to achieve an impact velocity of 6.05 ±0.1 m/s measured at the center of the pendulum...
49 CFR 572.187 - Lumbar spine.
Code of Federal Regulations, 2010 CFR
2010-10-01
...-headform assembly to the Part 572 pendulum test fixture per procedure in § 572.183(b)(2) and as shown in... assembly (175-5506) to 50 ± 5 in-lb; (3) Release the pendulum from a height sufficient to allow it to fall freely to achieve an impact velocity of 6.05 ±0.1 m/s measured at the center of the pendulum...
49 CFR 572.187 - Lumbar spine.
Code of Federal Regulations, 2014 CFR
2014-10-01
...-headform assembly to the Part 572 pendulum test fixture per procedure in § 572.183(b)(2) and as shown in... assembly (175-5506) to 50 ±5 in-lb; (3) Release the pendulum from a height sufficient to allow it to fall freely to achieve an impact velocity of 6.05 ±0.1 m/s measured at the center of the pendulum...
Background/Objectives. Passive sampling is becoming a frequently used measurement technique at Superfund sites with contaminated sediments. Passive sampling measures the concentrations of freely dissolved chemicals (Cfrees) in the sediment interstitial water. The freely dissol...
A Person Stands on a Balance in an Elevator: What Happens When the Elevator Starts to Fall?
NASA Astrophysics Data System (ADS)
Baluković, Jasmina; Slisko, Josip; Cruz, Adrián Corona
2018-03-01
Physics textbook authors commonly introduce the concept of weightlessness (apparent or real) through a "thought experiment" in which a person weighs herself or himself in an elevator. When the elevator falls freely, the spring balance should show zero weight. There is an unresolved controversy about how this "zero reading" comes about. Drawings in some books, the first of which appeared in a book of Perelman 80 years ago, show that the person continues to be in contact with the balance. It means that "zero weight" arises as a consequence of "the fact" that the falling person and balance, although in contact, don't press on each other. Drawings in other books, among them those elaborated by NASA, represent the person and the balance launched upward and floating separately in midair. Using a homemade "falling box" with attached video camera, we did initial experiments for a very simplified but basically similar situation. The results that we obtained suggest that, in a free-falling elevator, a real balance would hardly launch a person upward.
2011-09-01
magazine of Navy Cyber Forces that promotes the advancement of Information Dominance through an open exchange of better practices, tactics, and... Information Dominance Corps is central to that effort. For the Department of Defense and the Navy to operate freely within the cyber domain, we must...Officer (CIO) Division on the staff of the Deputy Chief of Naval Operations for Information Dominance (OPNAV N2/N6). Fleet assignments include combat
Absolute gravity measurements in California
NASA Astrophysics Data System (ADS)
Zumberge, M. A.; Sasagawa, G.; Kappus, M.
1986-08-01
An absolute gravity meter that determines the local gravitational acceleration by timing a freely falling mass with a laser interferometer has been constructed. The instrument has made measurements at 11 sites in California, four in Nevada, and one in France. The uncertainty in the results is typically 10 microgal. Repeated measurements have been made at several of the sites; only one shows a substantial change in gravity.
Palatini variation of curvature-squared action and gravitational collapse
NASA Technical Reports Server (NTRS)
Shahid-Saless, Bahman
1991-01-01
It is shown that Palatini variation of a class of gravitational actions based on a quadratic generalization of the Einstein-Hilbert action results in a metric-incompatible theory of gravity but one that satisfies Birkhoff's theorem. The usual fourth-order field equations are replaced by two second-order equations. Application of the field equations to a model of freely falling dust are discussed.
Shawen, Nicholas; Lonini, Luca; Mummidisetty, Chaithanya Krishna; Shparii, Ilona; Albert, Mark V; Kording, Konrad; Jayaraman, Arun
2017-10-11
Automatically detecting falls with mobile phones provides an opportunity for rapid response to injuries and better knowledge of what precipitated the fall and its consequences. This is beneficial for populations that are prone to falling, such as people with lower limb amputations. Prior studies have focused on fall detection in able-bodied individuals using data from a laboratory setting. Such approaches may provide a limited ability to detect falls in amputees and in real-world scenarios. The aim was to develop a classifier that uses data from able-bodied individuals to detect falls in individuals with a lower limb amputation, while they freely carry the mobile phone in different locations and during free-living. We obtained 861 simulated indoor and outdoor falls from 10 young control (non-amputee) individuals and 6 individuals with a lower limb amputation. In addition, we recorded a broad database of activities of daily living, including data from three participants' free-living routines. Sensor readings (accelerometer and gyroscope) from a mobile phone were recorded as participants freely carried it in three common locations-on the waist, in a pocket, and in the hand. A set of 40 features were computed from the sensors data and four classifiers were trained and combined through stacking to detect falls. We compared the performance of two population-specific models, trained and tested on either able-bodied or amputee participants, with that of a model trained on able-bodied participants and tested on amputees. A simple threshold-based classifier was used to benchmark our machine-learning classifier. The accuracy of fall detection in amputees for a model trained on control individuals (sensitivity: mean 0.989, 1.96*standard error of the mean [SEM] 0.017; specificity: mean 0.968, SEM 0.025) was not statistically different (P=.69) from that of a model trained on the amputee population (sensitivity: mean 0.984, SEM 0.016; specificity: mean 0.965, SEM 0.022). Detection of falls in control individuals yielded similar results (sensitivity: mean 0.979, SEM 0.022; specificity: mean 0.991, SEM 0.012). A mean 2.2 (SD 1.7) false alarms per day were obtained when evaluating the model (vs mean 122.1, SD 166.1 based on thresholds) on data recorded as participants carried the phone during their daily routine for two or more days. Machine-learning classifiers outperformed the threshold-based one (P<.001). A mobile phone-based fall detection model can use data from non-amputee individuals to detect falls in individuals walking with a prosthesis. We successfully detected falls when the mobile phone was carried across multiple locations and without a predetermined orientation. Furthermore, the number of false alarms yielded by the model over a longer period of time was reasonably low. This moves the application of mobile phone-based fall detection systems closer to a real-world use case scenario. ©Nicholas Shawen, Luca Lonini, Chaithanya Krishna Mummidisetty, Ilona Shparii, Mark V Albert, Konrad Kording, Arun Jayaraman. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 11.10.2017.
30 CFR 56.14106 - Falling object protection.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Falling object protection. 56.14106 Section 56... Equipment Safety Devices and Maintenance Requirements § 56.14106 Falling object protection. (a) Fork-lift trucks, front-end loaders, and bulldozers shall be provided with falling object protective structures if...
30 CFR 57.14106 - Falling object protection.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Falling object protection. 57.14106 Section 57... Equipment Safety Devices and Maintenance Requirements § 57.14106 Falling object protection. (a) Fork-lift trucks, front-end loaders, and bulldozers shall be provided with falling object protective structures if...
30 CFR 56.14106 - Falling object protection.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Falling object protection. 56.14106 Section 56... Equipment Safety Devices and Maintenance Requirements § 56.14106 Falling object protection. (a) Fork-lift trucks, front-end loaders, and bulldozers shall be provided with falling object protective structures if...
30 CFR 57.14106 - Falling object protection.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Falling object protection. 57.14106 Section 57... Equipment Safety Devices and Maintenance Requirements § 57.14106 Falling object protection. (a) Fork-lift trucks, front-end loaders, and bulldozers shall be provided with falling object protective structures if...
30 CFR 56.14106 - Falling object protection.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Falling object protection. 56.14106 Section 56... Equipment Safety Devices and Maintenance Requirements § 56.14106 Falling object protection. (a) Fork-lift trucks, front-end loaders, and bulldozers shall be provided with falling object protective structures if...
29 CFR 1926.759 - Falling object protection.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 29 Labor 8 2014-07-01 2014-07-01 false Falling object protection. 1926.759 Section 1926.759 Labor... (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Steel Erection § 1926.759 Falling object... aloft, shall be secured against accidental displacement. (b) Protection from falling objects other than...
29 CFR 1926.759 - Falling object protection.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 29 Labor 8 2011-07-01 2011-07-01 false Falling object protection. 1926.759 Section 1926.759 Labor... (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Steel Erection § 1926.759 Falling object... aloft, shall be secured against accidental displacement. (b) Protection from falling objects other than...
30 CFR 57.14106 - Falling object protection.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Falling object protection. 57.14106 Section 57... Equipment Safety Devices and Maintenance Requirements § 57.14106 Falling object protection. (a) Fork-lift trucks, front-end loaders, and bulldozers shall be provided with falling object protective structures if...
29 CFR 1926.759 - Falling object protection.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 29 Labor 8 2010-07-01 2010-07-01 false Falling object protection. 1926.759 Section 1926.759 Labor... (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Steel Erection § 1926.759 Falling object... aloft, shall be secured against accidental displacement. (b) Protection from falling objects other than...
29 CFR 1926.759 - Falling object protection.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 29 Labor 8 2012-07-01 2012-07-01 false Falling object protection. 1926.759 Section 1926.759 Labor... (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Steel Erection § 1926.759 Falling object... aloft, shall be secured against accidental displacement. (b) Protection from falling objects other than...
30 CFR 57.14106 - Falling object protection.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Falling object protection. 57.14106 Section 57... Equipment Safety Devices and Maintenance Requirements § 57.14106 Falling object protection. (a) Fork-lift trucks, front-end loaders, and bulldozers shall be provided with falling object protective structures if...
30 CFR 57.14106 - Falling object protection.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Falling object protection. 57.14106 Section 57... Equipment Safety Devices and Maintenance Requirements § 57.14106 Falling object protection. (a) Fork-lift trucks, front-end loaders, and bulldozers shall be provided with falling object protective structures if...
29 CFR 1926.759 - Falling object protection.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 29 Labor 8 2013-07-01 2013-07-01 false Falling object protection. 1926.759 Section 1926.759 Labor... (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Steel Erection § 1926.759 Falling object... aloft, shall be secured against accidental displacement. (b) Protection from falling objects other than...
30 CFR 56.14106 - Falling object protection.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Falling object protection. 56.14106 Section 56... Equipment Safety Devices and Maintenance Requirements § 56.14106 Falling object protection. (a) Fork-lift trucks, front-end loaders, and bulldozers shall be provided with falling object protective structures if...
30 CFR 56.14106 - Falling object protection.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Falling object protection. 56.14106 Section 56... Equipment Safety Devices and Maintenance Requirements § 56.14106 Falling object protection. (a) Fork-lift trucks, front-end loaders, and bulldozers shall be provided with falling object protective structures if...
Geodetic precession or dragging of inertial frames
NASA Technical Reports Server (NTRS)
Ashby, Neil; Shahid-Saless, Bahman
1989-01-01
In General Relativity, the Principle of General Covariance allows one to describe phenomena by means of any convenient choice of coordinate system. Here, it is shown that the geodetic precession of a gyroscope orbiting a spherically symmetric, nonrotating mass can be recast as a Lense-Thirring frame-dragging effect, in an appropriately chosen coordinate frame whose origin falls freely along with the gyroscope and whose spatial coordinate axes point in fixed directions.
Soot Formation in Freely-Propagating Laminar Premixed Flames
NASA Technical Reports Server (NTRS)
Lin, K.-C.; Hassan, M. I.; Faeth, G. M.
1997-01-01
Soot formation within hydrocarbon-fueled flames is an important unresolved problem of combustion science. Thus, the present study is considering soot formation in freely-propagating laminar premixed flames, exploiting the microgravity environment to simplify measurements at the high-pressure conditions of interest for many practical applications. The findings of the investigation are relevant to reducing emissions of soot and continuum radiation from combustion processes, to improving terrestrial and spacecraft fire safety, and to developing methods of computational combustion, among others. Laminar premixed flames are attractive for studying soot formation because they are simple one-dimensional flows that are computationally tractable for detailed numerical simulations. Nevertheless, studying soot-containing burner-stabilized laminar premixed flames is problematical: spatial resolution and residence times are limited at the pressures of interest for practical applications, flame structure is sensitive to minor burner construction details so that experimental reproducibility is not very good, consistent burner behavior over the lengthy test programs needed to measure soot formation properties is hard to achieve, and burners have poor durability. Fortunately, many of these problems are mitigated for soot-containing, freely-propagating laminar premixed flames. The present investigation seeks to extend work in this laboratory for various soot processes in flames by observing soot formation in freely-propagating laminar premixed flames. Measurements are being made at both Normal Gravity (NG) and MicroGravity (MG), using a short-drop free-fall facility to provide MG conditions.
Systems and Methods for Imaging of Falling Objects
NASA Technical Reports Server (NTRS)
Fallgatter, Cale (Inventor); Garrett, Tim (Inventor)
2014-01-01
Imaging of falling objects is described. Multiple images of a falling object can be captured substantially simultaneously using multiple cameras located at multiple angles around the falling object. An epipolar geometry of the captured images can be determined. The images can be rectified to parallelize epipolar lines of the epipolar geometry. Correspondence points between the images can be identified. At least a portion of the falling object can be digitally reconstructed using the identified correspondence points to create a digital reconstruction.
NASA Astrophysics Data System (ADS)
Wang, Shaofeng; Yao, Yin; Bai, Jianhui; Wang, Rui
2017-04-01
This paper investigated the intermediate states and the structure evolution of the dislocation in graphene when it falls freely from the saddle point of the energy landscape. The O-type dislocation, an unstable equilibrium structure located at the saddle point, is obtained from the lattice theory of the dislocation structure and improved by the ab initio calculation to take the buckling into account. Intermediate states along the kinetics path in the falling process are obtained from the ab initio simulation. Once the dislocation falls from the saddle point to the energy valley, this O-type dislocation transforms into the stable structure that is referred to as the B-type dislocation, and in the meantime, it moves a distance that equals half a Burgers vector. The structure evolution and the energy variation in the free-falling process are revealed explicitly. It is observed that rather than smooth change, a platform manifests itself in the energy curve. The unusual behaviour in the energy curve is mainly originated from symmetry breaking and bond formation in the dislocation core. The results can provide deep insight in the mechanism of the brittle feature of covalent materials.
The happiest thought of Einstein's life.
NASA Astrophysics Data System (ADS)
Heller, M.
It is a commonly told story that Einstein formulated his famous principle of equivalence when thinking about what happens in a freely falling elevator, and that it was an original idea of his genius distinguished by the rare capability to see deep problems in the most ordinary things. In the reading of Einstein's and Ernst Mach's works the author has discovered that it was not a physicist in an elevator which led to the principle of equivalence but rather somebody falling from a roof; moreover, the idea behind the principle was not invented by Einstein himself but rather read by him from the book by Mach entitled The Science of Mechanics. The influence this book had on young Einstein is very well known.
Effect of particle moment of inertia on the dynamics and wakes of freely rising cylinders
NASA Astrophysics Data System (ADS)
Mathai, Varghese; Zhu, Xiaojue; Sun, Chao; Lohse, Detlef
2017-11-01
We perform a numerical study on the two-dimensional motions and wakes of freely rising and falling circular cylinders in quiescent fluid. We show that the amplitude of oscillation and the overall system-dynamics are intricately linked to two parameters: the particle's mass-density relative to the fluid m* ≡ρp /ρf , and its relative moment-of-inertia I* ≡Ip /If . Using over 144 combinations of m* and I*, we comprehensively map out the parameter space covering very heavy (m* > 10) to very buoyant (m* < 0.1) particles at fixed Galileo number (Ga = 500). The entire data collapses into two scaling regimes demarcated by a transitional Strouhal number, Stt 0.17 . Stt separates a mass-dominated regime from a regime dominated by the particle's moment of inertia. A shift from one regime to the other also marks a gradual transition in the wake-shedding pattern: from the classical 2 S (2-Single) vortex mode to a 2 P (2-Pairs) mode of wake vortices. Thus, autorotation, triggered by moment of inertia reduction, can significantly enhance the translational oscillations of freely rising isotropic bodies.
30 CFR 77.403 - Mobile equipment; falling object protective structures (FOPS).
Code of Federal Regulations, 2012 CFR
2012-07-01
... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Mobile equipment; falling object protective... AREAS OF UNDERGROUND COAL MINES Safeguards for Mechanical Equipment § 77.403 Mobile equipment; falling... underground coal mines shall be provided with substantial falling object protective structures (FOPS). FOPS...
30 CFR 77.403 - Mobile equipment; falling object protective structures (FOPS).
Code of Federal Regulations, 2014 CFR
2014-07-01
... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Mobile equipment; falling object protective... AREAS OF UNDERGROUND COAL MINES Safeguards for Mechanical Equipment § 77.403 Mobile equipment; falling... underground coal mines shall be provided with substantial falling object protective structures (FOPS). FOPS...
30 CFR 77.403 - Mobile equipment; falling object protective structures (FOPS).
Code of Federal Regulations, 2013 CFR
2013-07-01
... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Mobile equipment; falling object protective... AREAS OF UNDERGROUND COAL MINES Safeguards for Mechanical Equipment § 77.403 Mobile equipment; falling... underground coal mines shall be provided with substantial falling object protective structures (FOPS). FOPS...
Clinical history and biologic age predicted falls better than objective functional tests.
Gerdhem, Paul; Ringsberg, Karin A M; Akesson, Kristina; Obrant, Karl J
2005-03-01
Fall risk assessment is important because the consequences, such as a fracture, may be devastating. The objective of this study was to find the test or tests that best predicted falls in a population-based sample of elderly women. The fall-predictive ability of a questionnaire, a subjective estimate of biologic age and objective functional tests (gait, balance [Romberg and sway test], thigh muscle strength, and visual acuity) were compared in 984 randomly selected women, all 75 years of age. A recalled fall was the most important predictor for future falls. Only recalled falls and intake of psycho-active drugs independently predicted future falls. Women with at least five of the most important fall predictors (previous falls, conditions affecting the balance, tendency to fall, intake of psychoactive medication, inability to stand on one leg, high biologic age) had an odds ratio of 11.27 (95% confidence interval 4.61-27.60) for a fall (sensitivity 70%, specificity 79%). The more time-consuming objective functional tests were of limited importance for fall prediction. A simple clinical history, the inability to stand on one leg, and a subjective estimate of biologic age were more important as part of the fall risk assessment.
Shirooka, Hidehiko; Nishiguchi, Shu; Fukutani, Naoto; Tashiro, Yuto; Nozaki, Yuma; Aoyama, Tomoki
2018-05-01
The association between subjective cognitive decline and falls has not been clearly determined. Our aim was to explore the effect of subjective cognitive decline on falls in community-dwelling older adults with or without objective cognitive decline. We included 470 older adults (mean age 73.6 ± 5.2; 329 women) living in the community and obtained data on fall history directly from the participants. Subjective cognitive decline was assessed using a self-administered question. Objective cognitive function was measured using the Mini-Mental State Examination. Statistical analyses were carried out separately for participants with objective cognitive decline and those without. A multiple logistic regression analysis showed that, among participants without objective cognitive decline, subjective cognitive decline was positively associated with falls [OR 1.91; 95% confidence interval (CI) 1.17-3.12; p = 0.01). Conversely, among participants with objective cognitive decline, subjective cognitive decline was negatively associated with falls (OR 0.07; 95% CI 0.01-0.85, p = 0.04). The result suggests that the objective-subjective disparity may affect falls in community-dwelling older adults. The presence of subjective cognitive decline was significantly positively associated with falls among cognitively intact older adults. However, among their cognitively impaired peers, the absence of subjective cognitive decline was positively associated with falls.
Other Questions with Respect to the Weak Equivalence Principle
NASA Astrophysics Data System (ADS)
Smarandache, Florentin
2017-01-01
A disc rotating at high speed will exert out-of-plane forces resembling an accelerating field. Is the principle of equivalence also applicable for this process? Will someone inside an elevator in free-fall and rotating around its vertical centre, feel a gravitational force? Or will he feel a gravitational force larger than what equivalence principle requires? Does the equivalence principle remain applicable here? An airplane flies at an altitude of 1 km. The co-pilot drops an elevator-room without a passenger inside it. After one second has elapsed, the co-pilot drops four grenades in the direction of the freely-falling elevator's path. The question: Will the grenades reach the elevator before it reaches the ground? If no, why? If yes, which grenade? How will the air resistance influence the outcome?
Bending at the base of a dragged-out viscous thread
NASA Astrophysics Data System (ADS)
Blount, Maurice; Lister, John
2007-11-01
We consider steady flow of a slender viscous thread falling from a nozzle onto a moving horizontal belt. We analyse the asymptotic limit of a very slender thread, and show that it has a boundary-layer structure in which bending stresses only become important near the belt, where they support a vertical stress and allow the velocity and rolling conditions to be satisfied. The outer solution is analogous to a viscous catenary, with velocity fixed at the belt and at the nozzle. There are three asymptotic regimes, with distinct structures, corresponding to the cases that the belt speed is larger than, smaller than, or close to the velocity of a freely falling thread. The implications for the onset and amplitude of meanders in the `fluid-mechanical sewing machine' are explored.
Velocity Memory Effect for polarized gravitational waves
NASA Astrophysics Data System (ADS)
Zhang, P.-M.; Duval, C.; Gibbons, G. W.; Horvathy, P. A.
2018-05-01
Circularly polarized gravitational sandwich waves exhibit, as do their linearly polarized counterparts, the Velocity Memory Effect: freely falling test particles in the flat after-zone fly apart along straight lines with constant velocity. In the inside zone their trajectories combine oscillatory and rotational motions in a complicated way. For circularly polarized periodic gravitational waves some trajectories remain bounded, while others spiral outward. These waves admit an additional "screw" isometry beyond the usual five. The consequences of this extra symmetry are explored.
Tandem Stance Avoidance Using Adaptive and Asymmetric Admittance Control for Fall Prevention.
Nakagawa, Shotaro; Hasegawa, Yasuhisa; Fukuda, Toshio; Kondo, Izumi; Tanimoto, Masanori; Di, Pei; Huang, Jian; Huang, Qiang
2016-05-01
Fall prevention is one of the most important functions of walking assistance devices for user's safety. It is preferable that these devices prevent the user from being in the state where the risk of falling is high rather than helping them recovering from falling motion. During turning, when the user is in the tandem stance, a state where both legs form a line along walking direction, a support base that is surrounded by two legs becomes small, and a stability margin becomes small. This paper therefore aims to prevent the tandem stance by using nonwearable robot "intelligent cane" for the elderly or physically challenged person. Generally, the behavior of the lower limb follows the upper body turning. This paper therefore introduces a cane robot control method which constrains the behavior of user's upper body. By adjusting an admittance parameter of the robot according to the positions of a support leg, the robot resists to turn while a support leg is on the same side of the turning direction. A swing leg on the turning direction side therefore freely moves to the turning direction, while a swing leg on the opposite direction side of turning hardly move to the turning direction.
30 CFR 57.10007 - Falling object protection.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Falling object protection. 57.10007 Section 57.10007 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... § 57.10007 Falling object protection. Guard nets or other suitable protection shall be provided where...
30 CFR 57.10007 - Falling object protection.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Falling object protection. 57.10007 Section 57.10007 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... § 57.10007 Falling object protection. Guard nets or other suitable protection shall be provided where...
30 CFR 56.10007 - Falling object protection.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Falling object protection. 56.10007 Section 56.10007 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... § 56.10007 Falling object protection. Guard nets or other suitable protection shall be provided where...
30 CFR 57.10007 - Falling object protection.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Falling object protection. 57.10007 Section 57.10007 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... § 57.10007 Falling object protection. Guard nets or other suitable protection shall be provided where...
30 CFR 56.10007 - Falling object protection.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Falling object protection. 56.10007 Section 56.10007 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... § 56.10007 Falling object protection. Guard nets or other suitable protection shall be provided where...
30 CFR 57.10007 - Falling object protection.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Falling object protection. 57.10007 Section 57.10007 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... § 57.10007 Falling object protection. Guard nets or other suitable protection shall be provided where...
30 CFR 56.10007 - Falling object protection.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Falling object protection. 56.10007 Section 56.10007 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... § 56.10007 Falling object protection. Guard nets or other suitable protection shall be provided where...
30 CFR 56.10007 - Falling object protection.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Falling object protection. 56.10007 Section 56.10007 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... § 56.10007 Falling object protection. Guard nets or other suitable protection shall be provided where...
30 CFR 56.10007 - Falling object protection.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Falling object protection. 56.10007 Section 56.10007 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... § 56.10007 Falling object protection. Guard nets or other suitable protection shall be provided where...
30 CFR 57.10007 - Falling object protection.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Falling object protection. 57.10007 Section 57.10007 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... § 57.10007 Falling object protection. Guard nets or other suitable protection shall be provided where...
Early Knowledge of Object Motion: Continuity and Inertia.
ERIC Educational Resources Information Center
Spelke, Elizabeth; And Others
1994-01-01
Investigated whether infants infer that a hidden, freely moving object will move continuously and smoothly. Six- to 10- month olds inferred that the object's path would be connected and unobstructed, in accord with continuity. Younger infants did not infer this, in accord with inertia. At 8 and 10 months, knowledge of inertia emerged but remained…
Determining the Drag Coefficient of Rotational Symmetric Objects Falling through Liquids
ERIC Educational Resources Information Center
Houari, Ahmed
2012-01-01
I will propose here a kinematic approach for measuring the drag coefficient of rotational symmetric objects falling through liquids. For this, I will show that one can obtain a measurement of the drag coefficient of a rotational symmetric object by numerically solving the equation of motion describing its fall through a known liquid contained in a…
Khairy, Mohammed; Muir, Derek; Teixeira, Camilla; Lohmann, Rainer
2014-08-19
Polyethylene passive samplers were deployed during summer and fall of 2011 in the lower Great Lakes to assess the spatial distribution and sources of gaseous and freely dissolved organochlorine pesticides (OCPs) and their air-water exchange. Average gaseous OCP concentrations ranged from nondetect to 133 pg/m(3). Gaseous concentrations of hexachlorobenzene, dieldrin, and chlordanes were significantly greater (Mann-Whitney test, p < 0.05) at Lake Erie than Lake Ontario. A multiple linear regression implied that both cropland and urban areas within 50 and 10 km buffer zones, respectively, were critical parameters to explain the total variability in atmospheric concentrations. Freely dissolved OCP concentrations (nondetect to 114 pg/L) were lower than previously reported. Aqueous half-lives generally ranged from 1.7 to 6.7 years. Nonetheless, concentrations of p,p'-DDE and chlordanes were higher than New York State Ambient Water Quality Standards for the protection of human health from the consumption of fish. Spatial distributions of freely dissolved OCPs in both lakes were influenced by loadings from areas of concern and the water circulation patterns. Flux calculations indicated net deposition of γ-hexachlorocyclohexane, heptachlor-epoxide, and α- and β-endosulfan (-0.02 to -33 ng/m(2)/day) and net volatilization of heptachlor, aldrin, trans-chlordane, and trans-nonachlor (0.0 to 9.0 ng/m(2)/day) in most samples.
Lee, Young-Sook; Chung, Wan-Young
2012-01-01
Vision-based abnormal event detection for home healthcare systems can be greatly improved using visual sensor-based techniques able to detect, track and recognize objects in the scene. However, in moving object detection and tracking processes, moving cast shadows can be misclassified as part of objects or moving objects. Shadow removal is an essential step for developing video surveillance systems. The goal of the primary is to design novel computer vision techniques that can extract objects more accurately and discriminate between abnormal and normal activities. To improve the accuracy of object detection and tracking, our proposed shadow removal algorithm is employed. Abnormal event detection based on visual sensor by using shape features variation and 3-D trajectory is presented to overcome the low fall detection rate. The experimental results showed that the success rate of detecting abnormal events was 97% with a false positive rate of 2%. Our proposed algorithm can allow distinguishing diverse fall activities such as forward falls, backward falls, and falling asides from normal activities. PMID:22368486
Generating OER by Recording Lectures: A Case Study
ERIC Educational Resources Information Center
Llamas-Nistal, Martín; Mikic-Fonte, Fernando A.
2014-01-01
The University of Vigo, Vigo, Spain, has the objective of making all the teaching material generated by its teachers freely available. To attain this objective, it encourages the development of Open Educational Resources, especially videos. This paper presents an experience of recording lectures and generating the corresponding videos as a step…
People vs. Object Orientation in Preschool Boys and Girls.
ERIC Educational Resources Information Center
Jennings, Kay D.
This study was undertaken to explore the cultural stereotype that boys are more object-oriented and girls are more people-oriented. A total of 38 white, middle class, preschool children were observed during their free play hour at nursery school when a variety of people and objects were freely available to them. Each child was observed with a time…
Striving for transparent and credible research: practical guidelines for behavioral ecologists
Winney, Isabel S.; Krystalli, Anna; Croucher, Michael
2017-01-01
Abstract Science is meant to be the systematic and objective study of the world but evidence suggests that scientific practices are sometimes falling short of this expectation. In this invited idea, we argue that any failure to conduct research according to a documented plan (lack of reliability) and/or any failure to ensure that reconducting the same project would provide the same finding (lack of reproducibility), will result in a low probability of independent studies reaching the same outcome (lack of replicability). After outlining the challenges facing behavioral ecology and science more broadly and incorporating advice from international organizations such as the Center for Open Science (COS), we present clear guidelines and tutorials on what we think open practices represent for behavioral ecologists. In addition, we indicate some of the currently most appropriate and freely available tools for adopting these practices. Finally, we suggest that all journals in our field, such as Behavioral Ecology, give additional weight to transparent studies and therefore provide greater incentives to align our scientific practices to our scientific values. Overall, we argue that producing demonstrably credible science is now fully achievable for the benefit of each researcher individually and for our community as a whole. PMID:29622916
Collisions near Kerr black holes: lower limit of energy between orbiting and incoming particles
NASA Astrophysics Data System (ADS)
Rutkowski, Mieszko
2017-01-01
In our paper we investigate the lower limit of collisional energy of test particles near the Kerr black hole. In particular we examine the minimal Lorentz factor between the freely falling particles and the particles orbiting around a black hole. We consider collisions on the innermost stable circular orbit and examine near-extreme case, where collisions take place near an event horizon. By fine-tuning the particles' angular momentum, the Lorentz factor of the collision can always be minimized to a value dependent on the black hole's spin. We identified that this minimal value is always less than 2√{2}-1/√{3} and more than √{12}-1/√{6} (the limits are the values for an extreme Kerr and Schwarzschild, respectively). It implies that this kind of collisions of compact objects are expected to be highly energetic near supermassive black holes. In addition, we show that an interaction between black hole's and particle's spins has an influence on minimal Lorentz factor. This contribution is nonnegligible for near-extreme black holes. We also discuss the relation between our results and sci-fi movie Interstellar.
Reply to ``Comment on `Quantum time-of-flight distribution for cold trapped atoms' ''
NASA Astrophysics Data System (ADS)
Ali, Md. Manirul; Home, Dipankar; Majumdar, A. S.; Pan, Alok K.
2008-02-01
In their comment Gomes [Phys. Rev. A 77, 026101 (2008)] have questioned the possibility of empirically testable differences existing between the semiclassical time of flight distribution for cold trapped atoms and a quantum distribution discussed by us recently [Ali , Phys. Rev. A 75, 042110 (2007).]. We argue that their criticism is based on a semiclassical treatment having restricted applicability for a particular trapping potential. Their claim does not preclude, in general, the possibility of differences between the semiclassical calculations and fully quantum results for the arrival time distribution of freely falling atoms.
Reply to 'Comment on 'Quantum time-of-flight distribution for cold trapped atoms''
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ali, Md. Manirul; Home, Dipankar; Pan, Alok K.
2008-02-15
In their comment Gomes et al. [Phys. Rev. A 77, 026101 (2008)] have questioned the possibility of empirically testable differences existing between the semiclassical time of flight distribution for cold trapped atoms and a quantum distribution discussed by us recently [Ali et al., Phys. Rev. A 75, 042110 (2007).]. We argue that their criticism is based on a semiclassical treatment having restricted applicability for a particular trapping potential. Their claim does not preclude, in general, the possibility of differences between the semiclassical calculations and fully quantum results for the arrival time distribution of freely falling atoms.
FRAT-up, a Web-based fall-risk assessment tool for elderly people living in the community.
Cattelani, Luca; Palumbo, Pierpaolo; Palmerini, Luca; Bandinelli, Stefania; Becker, Clemens; Chesani, Federico; Chiari, Lorenzo
2015-02-18
About 30% of people over 65 are subject to at least one unintentional fall a year. Fall prevention protocols and interventions can decrease the number of falls. To be effective, a prevention strategy requires a prior step to evaluate the fall risk of the subjects. Despite extensive research, existing assessment tools for fall risk have been insufficient for predicting falls. The goal of this study is to present a novel web-based fall-risk assessment tool (FRAT-up) and to evaluate its accuracy in predicting falls, within a context of community-dwelling persons aged 65 and up. FRAT-up is based on the assumption that a subject's fall risk is given by the contribution of their exposure to each of the known fall-risk factors. Many scientific studies have investigated the relationship between falls and risk factors. The majority of these studies adopted statistical approaches, usually providing quantitative information such as odds ratios. FRAT-up exploits these numerical results to compute how each single factor contributes to the overall fall risk. FRAT-up is based on a formal ontology that enlists a number of known risk factors, together with quantitative findings in terms of odds ratios. From such information, an automatic algorithm generates a rule-based probabilistic logic program, that is, a set of rules for each risk factor. The rule-based program takes the health profile of the subject (in terms of exposure to the risk factors) and computes the fall risk. A Web-based interface allows users to input health profiles and to visualize the risk assessment for the given subject. FRAT-up has been evaluated on the InCHIANTI Study dataset, a representative population-based study of older persons living in the Chianti area (Tuscany, Italy). We compared reported falls with predicted ones and computed performance indicators. The obtained area under curve of the receiver operating characteristic was 0.642 (95% CI 0.614-0.669), while the Brier score was 0.174. The Hosmer-Lemeshow test indicated statistical significance of miscalibration. FRAT-up is a web-based tool for evaluating the fall risk of people aged 65 or up living in the community. Validation results of fall risks computed by FRAT-up show that its performance is comparable to externally validated state-of-the-art tools. A prototype is freely available through a web-based interface. ClinicalTrials.gov NCT01331512 (The InChianti Follow-Up Study); http://clinicaltrials.gov/show/NCT01331512 (Archived by WebCite at http://www.webcitation.org/6UDrrRuaR).
New methods for fall risk prediction.
Ejupi, Andreas; Lord, Stephen R; Delbaere, Kim
2014-09-01
Accidental falls are the leading cause of injury-related death and hospitalization in old age, with over one-third of the older adults experiencing at least one fall or more each year. Because of limited healthcare resources, regular objective fall risk assessments are not possible in the community on a large scale. New methods for fall prediction are necessary to identify and monitor those older people at high risk of falling who would benefit from participating in falls prevention programmes. Technological advances have enabled less expensive ways to quantify physical fall risk in clinical practice and in the homes of older people. Recently, several studies have demonstrated that sensor-based fall risk assessments of postural sway, functional mobility, stepping and walking can discriminate between fallers and nonfallers. Recent research has used low-cost, portable and objective measuring instruments to assess fall risk in older people. Future use of these technologies holds promise for assessing fall risk accurately in an unobtrusive manner in clinical and daily life settings.
Using a PC and external media to quantitatively investigate electromagnetic induction
NASA Astrophysics Data System (ADS)
Bonanno, A.; Bozzo, G.; Camarca, M.; Sapia, P.
2011-07-01
In this article we describe an experimental learning path about electromagnetic induction which uses an Atwood machine where one of the two hanging bodies is a cylindrical magnet falling through a plexiglass guide, surrounded either by a coil or by a copper pipe. The first configuration (magnet falling across a coil) allows students to quantitatively study the Faraday-Neumann-Lenz law, while the second configuration (falling through a copper pipe) permits learners to investigate the complex phenomena of induction by quantifying the amount of electric power dissipated through the pipe as a result of Foucault eddy currents, when the magnet travels through the pipe. The magnet's fall acceleration can be set by adjusting the counterweight of the Atwood machine so that both the kinematic quantities associated with it and the electromotive force induced within the coil are continuously and quantitatively monitored (respectively, by a common personal computer (PC) equipped with a webcam and by freely available software that makes it possible to use the audio card to convert the PC into an oscilloscope). Measurements carried out when the various experimental parameters are changed provide a useful framework for a thorough understanding and clarification of the conceptual nodes related to electromagnetic induction. The proposed learning path is under evaluation in various high schools participating in the project 'Lauree Scientifiche' promoted by the Italian Department of Education.
Using Artificial Intelligence To Teach English to Deaf People. Final Report.
ERIC Educational Resources Information Center
Loritz, Donald; Zambrano, Robert
This report describes a project to develop an English grammar-checking word processor intended for use by college students with hearing impairments. The project succeeded in its first objective, achievement of 92 percent parsing accuracy across the freely written compositions of college-bound deaf students. The second objective, ability to use the…
Collado-Mateo, D.; Gallego-Diaz, J. M.; Adsuar, J. C.; Domínguez-Muñoz, F. J.; Olivares, P. R.; Gusi, N.
2015-01-01
Objective. To evaluate fear of falling, number of falls, and balance performance in women with FM and to examine the relationship between these variables and others, such as balance performance, quality of life, age, pain, and impact of fibromyalgia. Methods. A total of 240 women participated in this cross-sectional study. Of these, 125 had fibromyalgia. Several variables were assessed: age, fear of falling from 0 to 100, number of falls, body composition, balance performance, lower limb strength, health-related quality of life, and impact of fibromyalgia. Results. Women with fibromyalgia reported more falls and more fear of falling. Fear of falling was associated with number of falls in the last year, stiffness, perceived balance problems, impact of FM, and HRQoL whereas the number of falls was related to fear of falling, balance performance with eyes closed, pain, tenderness to touch level, anxiety, self-reported balance problems, impact of FM, and HRQoL. Conclusion. FM has an impact on fear of falling, balance performance, and number of falls. Perceived balance problems seem to be more closely associated with fear of falling than objective balance performance. PMID:26618173
Bridging the Conceptual Gap between Free Fall and Drag-Dominated Regimes
ERIC Educational Resources Information Center
de Obaldia, Elida; Miller, Norma; Wittel, Fred; Jaimison, George; Wallis, Kendra
2016-01-01
Some misconceptions about physics are hard to change. For example, students continue to believe that heavier objects fall faster than light ones, even after a year of physics instruction. Physics misconceptions are persistent. Light objects do fall more slowly if their size-to-weight ratio is sufficient for drag to be appreciable. Motion through a…
Patient centered fall risk awareness perspectives: clinical correlates and fall risk
Verghese, Joe
2016-01-01
Background While objective measures to assess risk of falls in older adults have been established; the value of patient self-reports in the context of falls is not known. Objectives To identify clinical correlates of patient centered fall risk awareness, and their validity for predicting falls. Design Prospective cohort study. Setting and Participants 316 non-demented and ambulatory community-dwelling older adults (mean age 78 years, 55% women). Measurements Fall risk awareness was assessed with a two-item questionnaire, which asked participants about overall likelihood and personal risk of falling over the next 12 months. Incident falls were recorded over study follow-up. Results Fifty-three participants (16.8%) responded positively to the first fall risk awareness question about being likely to have a fall in the next 12 months, and 100 (31.6%) reported being at personal risk of falling over the next 12 months. There was only fair correlation (kappa 0.370) between responses on the two questions. Prior falls and depressive symptoms were associated with positive responses on both fall risk awareness questions. Age and other established fall risk factors were not associated with responses on both fall risk awareness questions. The fall risk awareness questionnaire did not predict incident falls or injurious falls. Conclusion Fall risk awareness is low in older adults. While patient centered fall risk awareness is not predictive of falls, subjective risk perceptions should be considered when designing fall preventive strategies as they may influence participation and behaviors. PMID:27801936
Edge effects on the fluttering characteristics of freely falling planar particles
NASA Astrophysics Data System (ADS)
Blay Esteban, Luis; Shrimpton, John; Ganapathisubramani, Bharathram
2018-06-01
The effect of particle edge geometry on the descent motion of freely falling planar particles is examined through experiments. Various planar particles, such as disk and polygons, with identical frontal areas (Ap) and different number of edges (or perimeter) are used. All particles are designed such that their values of Galileo number (G ) and dimensionless moment of inertia (I*) correspond to the previously identified fluttering regime of particle motion. Several modes of secondary motion are observed for the same particle and conditions, and these are not equally probable. This probability depends on the particle shape. Disks and heptagons were found to prefer a "planar zig-zag" behavior. These planar motions are composed of gliding sweeps and turning sections. As the number of sides in the polygon decreases, i.e., for hexagons and pentagons, the trajectory transitions to a more three-dimensional form. These trajectories were found to be restricted to one plane per swing, but the subsequent swings are in other planes. Further decrease in number of sides to a square results in the trajectories having a severe out-of-plane motion. These subregimes of particle motion within the fluttering regime are consistent with those reported for disks in previous studies. Based on this information, a length scale that accounts for the frontal area of the particles and its edge geometry (i.e., perimeter) is proposed. This length scale represents an approach to determine an equivalent disk for planar particles such that the phase diagram in the Reynolds number (Re) and dimensionless moment of inertia (I*) domain can be used to characterize the motion of planar particles with different frontal geometries. However, further experiments covering other domains of the regime map are needed to verify its universality.
Addressing wild turkey population declines using structured decision making
Robinson, Kelly F.; Fuller, Angela K.; Schiavone, Michael V.; Swift, Bryan L.; Diefenbach, Duane R.; Siemer, William F.; Decker, Daniel J.
2017-01-01
We present a case study from New York, USA, of the use of structured decision making (SDM) to identify fall turkey harvest regulations that best meet stakeholder objectives, in light of recent apparent declines in abundance of wild turkeys in the northeastern United States. We used the SDM framework to incorporate the multiple objectives associated with turkey hunting, stakeholder desires, and region-specific ecological and environmental factors that could influence fall harvest. We identified a set of 4 fall harvest regulations, composed of different season lengths and bag limits, and evaluated their relative achievement of the objectives. We used a stochastic turkey population model, statistical modeling, and expert elicitation to evaluate the consequences of each harvest regulation on each of the objectives. We conducted a statewide mail survey of fall turkey hunters in New York to gather the necessary information to evaluate tradeoffs among multiple objectives associated with hunter satisfaction. The optimal fall harvest regulation was a 2-week season and allowed for the harvest of 1 bird/hunter. This regulation was the most conservative of those evaluated, reflecting the concerns about recent declines in turkey abundance among agency wildlife biologists and the hunting public. Depending on the region of the state, the 2-week, 1-bird regulation was predicted to result in 7–32% more turkeys on the landscape after 5 years. The SDM process provided a transparent framework for setting fall turkey harvest regulations and reduced potential stakeholder conflict by explicitly taking the multiple objectives of different stakeholder groups into account.
Inclusions in freely suspended smectic films
NASA Astrophysics Data System (ADS)
Stannarius, Ralf; Harth, Kirsten
Smectic liquid crystal phases have a unique property: Like soap solutions, they can form stable freely suspended films. Their aspect ratios can be larger than one million to one. Such films can serve as models for two-dimensional (2D) uids, with or without in-plane anisotropy. Solid or liquid inclusions trapped in these films by capillary forces can move in the film plane and interact with other inclusions, with film thickness gradients or the film boundaries, and even with the local orientation field. We describe preparation techniques to incorporate particles or droplets in thin smectic films, and optical observation methods. Several aspects make inclusions in freely suspended films interesting research objects: They provide rich information on capillary forces as well as surface and interfacial tensions, they can serve as platforms for hydrodynamic studies in 2D, and they may help to understand coalescence dynamics at the transition from 2D to 3D...
NASA Astrophysics Data System (ADS)
Usman, K.; Walayat, K.; Mahmood, R.; Kousar, N.
2018-06-01
We have examined the behavior of solid particles in particulate flows. The interaction of particles with each other and with the fluid is analyzed. Solid particles can move freely through a fixed computational mesh using an Eulerian approach. Fictitious boundary method (FBM) is used for treating the interaction between particles and the fluid. Hydrodynamic forces acting on the particle's surface are calculated using an explicit volume integral approach. A collision model proposed by Glowinski, Singh, Joseph and coauthors is used to handle particle-wall and particle-particle interactions. The particulate flow is computed using multigrid finite element solver FEATFLOW. Numerical experiments are performed considering two particles falling and colliding and sedimentation of many particles while interacting with each other. Results for these experiments are presented and compared with the reference values. Effects of the particle-particle interaction on the motion of the particles and on the physical behavior of the fluid-particle system has been analyzed.
Quantum information erasure inside black holes
Lowe, David A.; Thorlacius, Larus
2015-12-15
An effective field theory for infalling observers in the vicinity of a quasi-static black hole is given in terms of a freely falling lattice discretization. The lattice model successfully reproduces the thermal spectrum of outgoing Hawking radiation, as was shown by Corley and Jacobson, but can also be used to model observations made by a typical low-energy observer who enters the black hole in free fall at a prescribed time. The explicit short distance cutoff ensures that, from the viewpoint of the infalling observer, any quantum information that entered the black hole more than a scrambling time earlier has beenmore » erased by the black hole singularity. Furthermore, this property, combined with the requirement that outside observers need at least of order the scrambling time to extract quantum information from the black hole, ensures that a typical infalling observer does not encounter drama upon crossing the black hole horizon in a theory where black hole information is preserved for asymptotic observers.« less
Simulation of General Physics laboratory exercise
NASA Astrophysics Data System (ADS)
Aceituno, P.; Hernández-Aceituno, J.; Hernández-Cabrera, A.
2015-01-01
Laboratory exercises are an important part of general Physics teaching, both during the last years of high school and the first year of college education. Due to the need to acquire enough laboratory equipment for all the students, and the widespread access to computers rooms in teaching, we propose the development of computer simulated laboratory exercises. A representative exercise in general Physics is the calculation of the gravity acceleration value, through the free fall motion of a metal ball. Using a model of the real exercise, we have developed an interactive system which allows students to alter the starting height of the ball to obtain different fall times. The simulation was programmed in ActionScript 3, so that it can be freely executed in any operative system; to ensure the accuracy of the calculations, all the input parameters of the simulations were modelled using digital measurement units, and to allow a statistical management of the resulting data, measurement errors are simulated through limited randomization.
On the Modulation of Meteoroid Falling by Solar Inertial Motion
NASA Astrophysics Data System (ADS)
Velasco Herrera, Victor Manuel; Cordero, Guadalupe; López Hernández, Juan Gabriel
2016-07-01
We present a historical report of falls of meteoroids over the last 400 years. We report here for the first time synchronization between observed meteors and solar barycentric parameters in 19.6 and 13.2 years periodicities using the multiple cross wavelet. These periodicities could be associated with Jupiter periodicities. Bodies falling on Earth can cause from minor damage to level of mass extinctions events. So understanding the modulation on meteoroid falling is important to determine patterns of falling of these objects, and to know when it is more probable to expect the entry of one of these object into the Earth's atmosphere
Fall Protection Introduction, #33462
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chochoms, Michael
The proper use of fall prevention and fall protection controls can reduce the risk of deaths and injuries caused by falls. This course, Fall Protection Introduction (#33462), is designed as an introduction to various types of recognized fall prevention and fall protection systems at Los Alamos National Laboratory (LANL), including guardrail systems, safety net systems, fall restraint systems, and fall arrest systems. Special emphasis is given to the components, inspection, care, and storage of personal fall arrest systems (PFASs). This course also presents controls for falling object hazards and emergency planning considerations for persons who have fallen.
NASA Astrophysics Data System (ADS)
Halliday, I.
1987-03-01
The first observational evidence of multiple meteorite falls from the same orbit is adduced from the February 6, 1980 fall of a meteorite precisely 3 yr after the fall of the Innisfree meteorite. Due consideration of the detection probability for two related objects with the meteorite camera network in western Canada suggests that the Innisfree brecciated LL chondrite was a near-surface fragment from a parent object whose radius was of the order of several tens of meters. A meteorite mass of 1.8 kg is predicted for the new object, whose recovery in the vicinity of Ridgedale, Saskatchewan, is now sought for the sake of comparison with the Innisfree chondrite.
NASA Astrophysics Data System (ADS)
Wald, Robert M.
There is no question that the formulation of general relativity was one of the most remarkable episodes in the history of science. As a physicist and researcher in general relativity, the story of the formulation of general relativity that I have heard (and repeated) many times goes basically as follows: In 1907, Einstein obtained his fundamental insight-the "equivalence principle"-that gravitation and inertia are intimately connected; a freely falling observer does not "feel" gravitational force. It then took the genius of Einstein many years of "struggle"-during which he mastered the elements of differential geometry-to formulate a theory that properly incorporated this idea. In November, 1915, he finally succeeded in formulating general relativity.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sharif, M., E-mail: msharif.math@pu.edu.pk; Haider, Nida, E-mail: nida.haider12@gmail.com
We study the center-of-mass energy of the particles colliding in the vicinity of acceleration and event horizons of the Plebanski and Demianski class of black holes. We calculate the collision energy of uncharged particles in the center-of-mass frame that are freely falling along the equatorial plane of a charged accelerating and rotating black hole with an NUT parameter. This energy turns out to be infinite in the non-extremal case, while in the extremal case, it becomes infinitely large near the event horizon only if the particle has the critical angular momentum. We conclude that the center-of-mass energy depends on themore » rotation and the NUT parameter.« less
The memory effect for plane gravitational waves
NASA Astrophysics Data System (ADS)
Zhang, P.-M.; Duval, C.; Gibbons, G. W.; Horvathy, P. A.
2017-09-01
We give an account of the gravitational memory effect in the presence of the exact plane wave solution of Einstein's vacuum equations. This allows an elementary but exact description of the soft gravitons and how their presence may be detected by observing the motion of freely falling particles. The theorem of Bondi and Pirani on caustics (for which we present a new proof) implies that the asymptotic relative velocity is constant but not zero, in contradiction with the permanent displacement claimed by Zel'dovich and Polnarev. A non-vanishing asymptotic relative velocity might be used to detect gravitational waves through the "velocity memory effect", considered by Braginsky, Thorne, Grishchuk, and Polnarev.
Novel sensing technology in fall risk assessment in older adults: a systematic review.
Sun, Ruopeng; Sosnoff, Jacob J
2018-01-16
Falls are a major health problem for older adults with significant physical and psychological consequences. A first step of successful fall prevention is to identify those at risk of falling. Recent advancement in sensing technology offers the possibility of objective, low-cost and easy-to-implement fall risk assessment. The objective of this systematic review is to assess the current state of sensing technology on providing objective fall risk assessment in older adults. A systematic review was conducted in accordance to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis statement (PRISMA). Twenty-two studies out of 855 articles were systematically identified and included in this review. Pertinent methodological features (sensing technique, assessment activities, outcome variables, and fall discrimination/prediction models) were extracted from each article. Four major sensing technologies (inertial sensors, video/depth camera, pressure sensing platform and laser sensing) were reported to provide accurate fall risk diagnostic in older adults. Steady state walking, static/dynamic balance, and functional mobility were used as the assessment activity. A diverse range of diagnostic accuracy across studies (47.9% - 100%) were reported, due to variation in measured kinematic/kinetic parameters and modelling techniques. A wide range of sensor technologies have been utilized in fall risk assessment in older adults. Overall, these devices have the potential to provide an accurate, inexpensive, and easy-to-implement fall risk assessment. However, the variation in measured parameters, assessment tools, sensor sites, movement tasks, and modelling techniques, precludes a firm conclusion on their ability to predict future falls. Future work is needed to determine a clinical meaningful and easy to interpret fall risk diagnosis utilizing sensing technology. Additionally, the gap between functional evaluation and user experience to technology should be addressed.
Numerical Study of motion of Falling Conical Graupel
NASA Astrophysics Data System (ADS)
Chueh, Chih-Che; Wang, Pao K.; Hashino, Tempei
2017-11-01
Each year, large hailstones falling from a thunderstorm cause massive loss of crops and properties, pose a serious threat to aviation, and, on occasion, some deaths in the world. Graupel particles often serve as hailstone embryos, and are frequently observed forms of convective precipitation almost everywhere. And it is sufficiently evident that the major factor that determines collision efficiency for ice accretion is the flow field. In the present study, the attitudes of freely-falling conical graupel particles with a realistic range of densities are investigated numerically by solving the transient Navier-Stokes equations and the body dynamics equations representing the 6-degrees-of-freedom motion, allowing us to determine the position and orientation of the graupel in response to the coupling of the hydrodynamic force and torque of the flow fields, gravitational force, as well as Magnus force due to self-rotation. The results show significant horizontal movements (on the order of 1 km in one hour) and also show that when Reynolds number is small, a typical damped oscillation occurs, whereas when Reynolds number is high, amplifying oscillation may occur which leads to more complicated and unpredictable flying attitudes such as tumbling. This study is partially supported by the US NSF Grant AGS-1633921 and research fund provided by the Academia Sinica, Taiwan.
Superconducting pipes and levitating magnets.
Levin, Yan; Rizzato, Felipe B
2006-12-01
Motivated by a beautiful demonstration of the Faraday and the Lenz laws in which a small neodymium magnet falls slowly through a conducting nonferromagnetic tube, we consider the dynamics of a magnet falling coaxially through a superconducting pipe. Unlike the case of normal conducting pipes, in which the magnet quickly reaches the terminal velocity, inside a superconducting tube the magnet falls freely. On the other hand, to enter the pipe the magnet must overcome a large electromagnetic energy barrier. For sufficiently strong magnets, the barrier is so large that the magnet will not be able to penetrate it and will be levitated over the mouth of the pipe. We calculate the work that must done to force the magnet to enter a superconducting tube. The calculations show that superconducting pipes are very efficient at screening magnetic fields. For example, the magnetic field of a dipole at the center of a short pipe of radius a and length L approximately > a decays, in the axial direction, with a characteristic length xi approximately 0.26a. The efficient screening of the magnetic field might be useful for shielding highly sensitive superconducting quantum interference devices. Finally, the motion of the magnet through a superconducting pipe is compared and contrasted to the flow of ions through a trans-membrane channel.
Superconducting pipes and levitating magnets
NASA Astrophysics Data System (ADS)
Levin, Yan; Rizzato, Felipe B.
2006-12-01
Motivated by a beautiful demonstration of the Faraday and the Lenz laws in which a small neodymium magnet falls slowly through a conducting nonferromagnetic tube, we consider the dynamics of a magnet falling coaxially through a superconducting pipe. Unlike the case of normal conducting pipes, in which the magnet quickly reaches the terminal velocity, inside a superconducting tube the magnet falls freely. On the other hand, to enter the pipe the magnet must overcome a large electromagnetic energy barrier. For sufficiently strong magnets, the barrier is so large that the magnet will not be able to penetrate it and will be levitated over the mouth of the pipe. We calculate the work that must done to force the magnet to enter a superconducting tube. The calculations show that superconducting pipes are very efficient at screening magnetic fields. For example, the magnetic field of a dipole at the center of a short pipe of radius a and length L≳a decays, in the axial direction, with a characteristic length ξ≈0.26a . The efficient screening of the magnetic field might be useful for shielding highly sensitive superconducting quantum interference devices. Finally, the motion of the magnet through a superconducting pipe is compared and contrasted to the flow of ions through a trans-membrane channel.
Sphere forming method and apparatus
NASA Technical Reports Server (NTRS)
Youngberg, C. L.; Miller, C. G.; Stephens, J. B.; Finnerty, A. A. (Inventor)
1983-01-01
A system is provided for forming small accurately spherical objects. Preformed largely spherical objects are supported at the opening of a conduit on the update of hot gas emitted from the opening, so the object is in a molten state. The conduit is suddenly jerked away at a downward incline, to allow the molten object to drop in free fall, so that surface tension forms a precise sphere. The conduit portion that has the opening, lies in a moderate vacuum chamber, and the falling sphere passes through the chamber and through a briefly opened valve into a tall drop tower that contains a lower pressure, to allow the sphere to cool without deformation caused by falling through air.
Possible Fengyun-1C debris fall
NASA Astrophysics Data System (ADS)
Golebiewska, J.; Nowak, M.; Muszyński, A.; Wnuk, E.
2017-05-01
A fall of small objects took place on 27th April 2012 in Wargowo village near Oborniki, about 25 km NW from Poznań (Poland). There was only one eye-witness of the fall, who found two separate pieces (ca. 2.7 cm and ca. 2 cm), with several small additional fragments. After microscopic observations and chemical analysis a meteoritic origin of these objects was excluded. They are identified as space debris, therefore man-made. The most probable source of the observed fall was space debris 35127 Fengyun 1C DEB, created during destruction of the Chinese weather satellite Fengyun-1C (FY-1C).
NASA Technical Reports Server (NTRS)
Zimmerman, M.
1979-01-01
The classical mechanics results for free precession which are needed in order to calculate the weak field, slow-motion, quadrupole-moment gravitational waves are reviewed. Within that formalism, algorithms are given for computing the exact gravitational power radiated and waveforms produced by arbitrary rigid-body freely-precessing sources. The dominant terms are presented in series expansions of the waveforms for the case of an almost spherical object precessing with a small wobble angle. These series expansions, which retain the precise frequency dependence of the waves, may be useful for gravitational astronomers when freely-precessing sources begin to be observed.
Kim, Wondae; Buchanan, John; Gabbard, Carl
2011-01-01
With an interest in identifying the variables that constrain arm choice when reaching, the authors had 11 right-handed participants perform free-choice and assigned-limb reaches at 9 object positions. The right arm was freely selected 100% of the time when reaching to positions at 30° and 40° into right hemispace. However, the left arm was freely selected to reach to positions at -30° and -40° in left hemispace 85% of the time. A comparison between free- and assigned-limb reaching kinematics revealed that free limb selection when reaching to the farthest positions was constrained by joint amplitude requirements and the time devoted to limb deceleration. Differences between free- and assigned-arm reaches were not evident when reaching to the midline and positions of ±10°, even though the right arm was freely selected most often for these positions. Different factors contribute to limb selection as a function of distance into a specific hemispace.
Free Falling in Stratified Fluids
NASA Astrophysics Data System (ADS)
Lam, Try; Vincent, Lionel; Kanso, Eva
2017-11-01
Leaves falling in air and discs falling in water are examples of unsteady descents due to complex interaction between gravitational and aerodynamic forces. Understanding these descent modes is relevant to many branches of engineering and science such as estimating the behavior of re-entry space vehicles to studying biomechanics of seed dispersion. For regularly shaped objects falling in homogenous fluids, the motion is relatively well understood. However, less is known about how density stratification of the fluid medium affects the falling behavior. Here, we experimentally investigate the descent of discs in both pure water and in stable linearly stratified fluids for Froude numbers Fr 1 and Reynolds numbers Re between 1000 -2000. We found that stable stratification (1) enhances the radial dispersion of the disc at landing, (2) increases the descent time, (3) decreases the inclination (or nutation) angle, and (4) decreases the fluttering amplitude while falling. We conclude by commenting on how the corresponding information can be used as a predictive model for objects free falling in stratified fluids.
Design and Development of the Observation and Analysis of Smectic Islands in Space Experiment
NASA Technical Reports Server (NTRS)
Hall, Nancy Rabel; Tin, Padetha; Sheehan, C. C.; Stannarius, R.; Trittel, T.; Clark, N.; Maclennan, J.; Glaser, M.; Park, C.
2012-01-01
The primary objective of Observation and Analysis of Smectic Islands in Space (OASIS) experiment is to exploit the unique characteristics of freely suspended liquid crystals in a microgravity environment to advance the understanding of fluid state physics
Impulse measurement using an Arduíno
NASA Astrophysics Data System (ADS)
Espindola, P. R.; Cena, C. R.; Alves, D. C. B.; Bozano, D. F.; Goncalves, A. M. B.
2018-05-01
In this paper, we propose a simple experimental apparatus that can measure the force variation over time to study the impulse-momentum theorem. In this proposal, a body attached to a rubber string falls freely from rest until it stretches and changes the linear momentum. During that process the force due to the tension on the rubber string is measured with a load cell by using an Arduíno board. We check the instrumental results with the basic concept of impulse, finding the area under the force versus time curve and comparing this with the linear momentum variation estimated from software analysis. The apparatus is presented as a simple and low cost alternative to mechanical physics laboratories.
Quantitative locomotion study of freely swimming micro-organisms using laser diffraction.
Magnes, Jenny; Susman, Kathleen; Eells, Rebecca
2012-10-25
Soil and aquatic microscopic organisms live and behave in a complex three-dimensional environment. Most studies of microscopic organism behavior, in contrast, have been conducted using microscope-based approaches, which limit the movement and behavior to a narrow, nearly two-dimensional focal field.(1) We present a novel analytical approach that provides real-time analysis of freely swimming C. elegans in a cuvette without dependence on microscope-based equipment. This approach consists of tracking the temporal periodicity of diffraction patterns generated by directing laser light through the cuvette. We measure oscillation frequencies for freely swimming nematodes. Analysis of the far-field diffraction patterns reveals clues about the waveforms of the nematodes. Diffraction is the process of light bending around an object. In this case light is diffracted by the organisms. The light waves interfere and can form a diffraction pattern. A far-field, or Fraunhofer, diffraction pattern is formed if the screen-to-object distance is much larger than the diffracting object. In this case, the diffraction pattern can be calculated (modeled) using a Fourier transform.(2) C. elegans are free-living soil-dwelling nematodes that navigate in three dimensions. They move both on a solid matrix like soil or agar in a sinusoidal locomotory pattern called crawling and in liquid in a different pattern called swimming.(3) The roles played by sensory information provided by mechanosensory, chemosensory, and thermosensory cells that govern plastic changes in locomotory patterns and switches in patterns are only beginning to be elucidated.(4) We describe an optical approach to measuring nematode locomotion in three dimensions that does not require a microscope and will enable us to begin to explore the complexities of nematode locomotion under different conditions.
NASA Astrophysics Data System (ADS)
Bassan, M.; Cavalleri, A.; De Laurentis, M.; De Marchi, F.; De Rosa, R.; Di Fiore, L.; Dolesi, R.; Finetti, N.; Garufi, F.; Grado, A.; Hueller, M.; Marconi, L.; Milano, L.; Minenkov, Y.; Pucacco, G.; Stanga, R.; Vetrugno, D.; Visco, M.; Vitale, S.; Weber, W. J.
2018-01-01
In this paper we report on measurements on actuation crosstalk, relevant to the gravitational reference sensors for LISA Pathfinder and LISA. In these sensors, a Test Mass (TM) falls freely within a system of electrodes used for readout and control. These measurements were carried out on ground with a double torsion pendulum that allowed us to estimate both the torque injected into the sensor when a control force is applied and, conversely, the force leaking into the translational degree of freedom due to the applied torque.The values measured on our apparatus (the engineering model of the LISA Pathfinder sensor) agree to within 0.2% (over a maximum measured crosstalk of 1%) with predictions of a mathematical model when measuring force to torque crosstalk, while it is somewhat larger than expected (up to 3.5%) when measuring torque to force crosstalk. However, the values in the relevant range, i.e. when the TM is well centered ( ± 10 μm) in the sensor, remain smaller than 0.2%, satisfying the LISA Pathfinder requirements.
Quantum jump from singularity to outside of black hole
NASA Astrophysics Data System (ADS)
Dündar, Furkan Semih; Hajian, Kamal
2016-02-01
Considering the role of black hole singularity in quantum evolution, a resolution to the firewall paradox is presented. It is emphasized that if an observer has the singularity as a part of his spacetime, then the semi-classical evolution would be non-unitary as viewed by him. Specifically, a free-falling observer inside the black hole would have a Hilbert space with non-unitary evolution; a quantum jump for particles encountering the singularity to outside of the horizon as late Hawking radiations. The non-unitarity in the jump resembles the one in collapse of wave function, but preserves entanglements. Accordingly, we elaborate the first postulate of black hole complementarity: freely falling observers who pass through the event horizon would have non-unitary evolution, while it does not have physically measurable effects for them. Besides, no information would be lost in the singularity. Taking the modified picture into account, the firewall paradox can be resolved, respecting No Drama. A by-product of our modification is that roughly half of the entropy of the black hole is released close to the end of evaporation in the shape of very hot Hawking radiation.
Are Older Adults Receiving Evidence-Based Advice to Prevent Falls Post-Discharge from Hospital?
ERIC Educational Resources Information Center
Lee, Den-Ching A.; Brown, Ted; Stolwyk, Rene; O'Connor, Daniel W.; Haines, Terry P.
2016-01-01
Background: Older adults experience a high rate of falls when they transition to community-living following discharge from hospital. Objectives: To describe the proportion of older adults who could recall having discussed falls and falls prevention strategies with a health professional within 6 months following discharge from hospital. To describe…
Falling and fall risk in adult patients with severe haemophilia.
Rehm, Hanna; Schmolders, Jan; Koob, Sebastian; Bornemann, Rahel; Goldmann, Georg; Oldenburg, Johannes; Pennekamp, Peter; Strauss, Andreas C
2017-05-10
The objective of this study was to define fall rates and to identify possible fall risk factors in adult patients with severe haemophilia. 147 patients with severe haemophilia A and B were evaluated using a standardized test battery consisting of demographic, medical and clinical variables and fall evaluation. 41 (27.9 %) patients reported a fall in the past 12 months, 22 (53.7 %) of them more than once. Young age, subjective gait insecurity and a higher number of artificial joints seem to be risk factors for falling. Falls seem to be a common phenomenon in patients with severe haemophilia. Fall risk screening and fall prevention should be implemented into daily practice.
Code of Federal Regulations, 2010 CFR
2010-07-01
..., perpetuate, and, where necessary, restore the wilderness character of the land and its specific values of... end: (a) Natural ecological succession will be allowed to operate freely to the extent feasible. (b... primitive conditions. (c) In resolving conflicts in resource use, wilderness values will be dominant to the...
Rethinking Canada's Higher Education Policy.
ERIC Educational Resources Information Center
Polster, Claire
2002-01-01
Rather than a public good that is freely shared, Canadian university research is increasingly privatized and commercialized and thus rendered accessible only to those who can pay for it. The effects include erosion of collegiality, institutional democracy, curiosity-driven basic research, objectivity, and consideration of disadvantaged groups. All…
Blood drop size in passive dripping from weapons.
Kabaliuk, N; Jermy, M C; Morison, K; Stotesbury, T; Taylor, M C; Williams, E
2013-05-10
Passive dripping, the slow dripping of blood under gravity, is responsible for some bloodstains found at crime scenes, particularly drip trails left by a person moving through the scene. Previous work by other authors has established relationships, under ideal conditions, between the size of the stain, the number of spines and satellite stains, the roughness of the surface, the size of the blood droplet and the height from which it falls. To apply these relationships to infer the height of fall requires independent knowledge of the size of the droplet. This work aims to measure the size of droplets falling from objects representative of hand-held weapons. Pig blood was used, with density, surface tension and viscosity controlled to fall within the normal range for human blood. Distilled water was also tested as a reference. Drips were formed from stainless steel objects with different roughnesses including cylinders of diameter between 10 and 100 mm, and flat plates. Small radius objects including a knife and a wrench were also tested. High speed images of the falling drops were captured. The primary blood drop size ranged from 4.15±0.11 mm up to 6.15±0.15 mm (depending on the object), with the smaller values from sharper objects. The primary drop size correlated only weakly with surface roughness, over the roughness range studied. The number of accompanying droplets increased with the object size, but no significant correlation with surface texture was observed. Dripping of blood produced slightly smaller drops, with more accompanying droplets, than dripping water. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
Measurement of rheologic property of blood by a falling-ball blood viscometer.
Eguchi, Yoko; Karino, Takeshi
2008-04-01
The viscosity of blood obtained by using a rotational viscometer decreases with the time elapsed from the beginning of measurement until it reaches a constant value determined by the magnitude of shear rate. It is not possible to obtain an initial value of viscosity at time t = 0 that is considered to exhibit an intrinsic property of the fluid by this method. Therefore, we devised a new method by which one can obtain the viscosity of various fluids that are not affected by both the time elapsed from the beginning of measurement and the magnitude of shear rate by considering the balance of the forces acting on a solid spherical particle freely falling in a quiescent viscous fluid. By using the new method, we studied the rheologic behavior of corn syrups, carboxy-methyl cellulose, and human blood; and compared the results with those obtained with a cone-and-plate viscometer. It was found that in the case of corn syrups and washed red cell suspensions in which no red cell aggregate (rouleau) was formed, the viscosity obtained with the two different methods were almost the same. In contrast to this, in the case of the whole blood in which massive aggregates were formed, the viscosity obtained with a falling-ball viscometer was much larger than that obtained with a cone-plate viscometer.
Xu, Z M; De Vel, E; Vinck, B; Van Cauwenberge, P
1995-01-01
The effects of rise-fall and plateau times for the Pa component of the middle-latency response (MLR) were investigated in normally hearing subjects, and an objective MLR threshold was measured in patients with low- and middle-tone hearing losses, using a selected stimulus-envelope time. Our results showed that the stimulus-envelope time (the rise-fall time and plateau time groups) affected the Pa component of the MLR (quality was determined by the (chi 2-test and amplitude by the F-test). The 4-2-4 tone-pips produced good Pa quality by visual inspection. However, our data revealed no statistically significant Na-Pa amplitude differences between the two subgroups studied when comparing the 2- and 4-ms rise-fall times and the 0- and 2-ms plateau times. In contrast, Na-Pa became significantly smaller from the 4-ms to the 6-ms rise-fall time and from the 2-ms to the 4-ms plateau time (paired t-test). This result allowed us to select the 2- or 4-ms rise-fall time and the 0- or 2-ms plateau time without influencing amplitude. Analysis of the stimulus spectral characteristics demonstrated that a rise-fall time of at least 2ms could prevent spectral splatter and indicated that a stimulus with a 5-ms rise-fall time had a greater frequency-specificity than a stimulus of 2-ms rise-fall time. When considering the synchronous discharge and frequency-specificity of MLR, our findings show that a rise-fall time of four periods with a plateau of two periods is an acceptable compromise for estimating the objective MLR threshold.(ABSTRACT TRUNCATED AT 250 WORDS)
Johansson, Jonas; Nordström, Anna; Gustafson, Yngve; Westling, Göran; Nordström, Peter
2017-11-01
fall-related injuries constitute major health risks in older individuals, and these risks are projected to increase in parallel with increasing human longevity. Impaired postural stability is a potential risk factor related to falls, although the evidence is inconclusive, partly due to the lack of prospective studies. This study aimed to investigate how objective measures of postural sway predict incident falls. this prospectively observational study included 1,877 community-dwelling individuals aged 70 years who participated in the Healthy Ageing Initiative between June 2012 and December 2015. postural sway was measured during eyes-open (EO) and eyes-closed (EC) trials using the Wii Balance Board. Functional mobility, muscle strength, objective physical activity and cognitive performance were also measured. Participants reported incident falls 6 and 12 months after the examination. during follow-up, 255 (14%) prospective fallers were identified. Division of centre of pressure (COP) sway lengths into quintiles revealed a nonlinear distribution of falls for EO trial data, but not EC trial data. After adjustment for multiple confounders, fall risk was increased by 75% for participants with COP sway lengths ≥400 mm during the EO trial (odds ratio [OR] 1.75, 95% confidence interval [CI] 1.09-2.79), and approximately doubled for sway lengths ≥920 mm during the EC trial (OR 1.90, 95% CI 1.12-3.22). objective measures of postural sway independently predict incident falls in older community-dwelling men and women. Further studies are needed to evaluate whether postural sway length is of interest for the prediction of incident falls in clinical settings. © The Author 2017. Published by Oxford University Press on behalf of the British Geriatrics Society.All rights reserved. For permissions, please email: journals.permissions@oup.com
Intuitive Physics of Free Fall: An Information Integration Approach to the Mass-Speed Belief
ERIC Educational Resources Information Center
Vicovaro, Michele
2014-01-01
In this study, the intuitive physics of free fall was explored using Information Integration Theory and Functional Measurement. The participants had to rate the speed of objects differing in mass and height of release at the end of an imagined free fall. According to physics, falling speed increases with height of release but it is substantially…
Trauma caused by falling objects at construction sites.
Atique, Sajid; Zarour, Ahmad; Siddiqui, Tariq; El-Menyar, Ayman; Maull, Kimball; Al Thani, Hassan; Latifi, Rifat
2012-09-01
Workplace-related injuries carry a significant health care challenge. The state of Qatar is developing rapidly, with much construction and an expanding industrial work force. This study aimed to assess the incidence and social impact of work-related injuries requiring hospitalization caused by falling objects at the construction sites. We performed a prospective study for all admissions, which resulted from falling objects between January 2008 and June 2010 at the only trauma center in the state of Qatar. Data were analyzed, and outcomes were described (mortality, length of hospital stay, and safety measures). Of the total injured patients (N = 4,302) admitted between January 2008 and June 2010, 185 (4%) had injuries caused purely by falling objects. Patients' mean age was 29 years, and 97% of the patients were men. All injuries occurred at construction sites. Most patients (86%) were brought by ambulance, and the reminder was brought by private vehicles. After initial evaluation and resuscitation, 120 patients (65%) were found to have a single-system injury, and 65 (35%) had multisystem injury. Operative interventions were required in 50% of the patients. Mean length of hospital stay varied from 6.5 days for single-system injuries to 19 days for multisystem injuries. Safety devices were used in 32 patients (17.3%). All of the 16 mortality cases (8.6%) were reported in multiple injuries. Traumatic injury caused by falling object represents a significant problem in a rapidly developing country. Many of these injuries could be prevented by following established safety guidelines. Epidemiologic study, level III.
Grosse, Constantino
2014-04-01
The description and interpretation of dielectric spectroscopy data usually require the use of analytical functions, which include unknown parameters that must be determined iteratively by means of a fitting procedure. This is not a trivial task and much effort has been spent to find the best way to accomplish it. While the theoretical approach based on the Levenberg-Marquardt algorithm is well known, no freely available program specifically adapted to the dielectric spectroscopy problem exists to the best of our knowledge. Moreover, even the more general commercial packages usually fail on the following aspects: (1) allow to keep temporarily fixed some of the parameters, (2) allow to freely specify the uncertainty values for each data point, (3) check that parameter values fall within prescribed bounds during the fitting process, and (4) allow to fit either the real, or the imaginary, or simultaneously both parts of the complex permittivity. A program that satisfies all these requirements and allows fitting any superposition of the Debye, Cole-Cole, Cole-Davidson, and Havriliak-Negami dispersions plus a conductivity term to measured dielectric spectroscopy data is presented. It is available on request from the author. Copyright © 2013 Elsevier Inc. All rights reserved.
NASA Technical Reports Server (NTRS)
Krisher, Timothy P.
1996-01-01
We consider the gravitational redshift effect measured by an observer in a local freely failing frame (LFFF) in the gravitational field of a massive body. For purely metric theories of gravity, the metric in a LFFF is expected to differ from that of flat spacetime by only "tidal" terms of order (GM/c(exp 2)R)(r'/R )(exp 2), where R is the distance of the observer from the massive body, and r' is the coordinate separation relative to the origin of the LFFF. A simple derivation shows that a violation of the equivalence principle for certain types of "clocks" could lead to a larger apparent redshift effect of order (1 - alpha)(G M/c(exp 2)R)(r'/R), where alpha parametrizes the violation (alpha = 1 for purely metric theories, such as general relativity). Therefore, redshift experiments in a LFFF with separated clocks can provide a new null test of the equivalence principle. With presently available technology, it is possible to reach an accuracy of 0.01% in the gravitational field of the Sun using an atomic clock orbiting the Earth. A 1% test in the gravitational field of the galaxy would be possible if an atomic frequency standard were flown on a space mission to the outer solar system.
Fear of falling as seen in the Multidisciplinary falls consultation.
Gaxatte, C; Nguyen, T; Chourabi, F; Salleron, J; Pardessus, V; Delabrière, I; Thévenon, A; Puisieux, F
2011-06-01
Fear of falling may be as debilitating as the fall itself, leading to a restriction in activities and even a loss of autonomy. The main objective was to evaluate the prevalence of the fear of falling among elderly fallers. The secondary objectives were to determine the factors associated with the fear of falling and evaluate the impact of this fear on the activity "getting out of the house". Prospective study conducted between 1995 and 2006 in which fallers and patients at high risk for falling were seen at baseline by the multidisciplinary falls consultation team (including a geriatrician, a neurologist and a physical medicine and rehabilitation physician) and then, again 6 month later, by the same geriatrician. The fear of falling was evaluated with a yes/no question: "are you afraid of falling?". Out of 635 patients with a mean age of 80.6 years, 502 patients (78%) expressed a fear of falling. Patients with fear of falling were not older than those who did not report this fear, but the former were mostly women (P<0,001), who experienced more falls in the 6 months preceding the consultation (P=0.01), reported more frequently a long period of time spent on the floor after a fall (P<0.001), had more balance disorders (P=0.002) and finally, were using more frequently a walking technical aid (P=0.02). Patients with fear of falling were not going out alone as much as the fearless group (31% vs 53%, P<0.0001). Eighty-two percent of patients in the fearful group admitted to avoiding going out because they were afraid of falling. The strong prevalence of the fear of falling observed in this population and its consequences in terms of restricted activities justifies systematically screening for it in fallers or patients at risk for falling. Copyright © 2011 Elsevier Masson SAS. All rights reserved.
Laboratory Test of the Galilean Universality of the Free Fall Experiment
ERIC Educational Resources Information Center
Christensen, Rasmus S.; Teiwes, Ricky; Petersen, Steffen V.; Uggerhøj, Ulrik I.; Jacoby, Bo
2014-01-01
There is a popular myth that Galileo dropped two objects of the same shape but different mass, noted their equal fall time, and concluded that gravitational motion is independent of the mass of the object. This paper demonstrates that this experiment--if actually performed--most likely would have yielded a different result and thus with modern…
Internal models and prediction of visual gravitational motion.
Zago, Myrka; McIntyre, Joseph; Senot, Patrice; Lacquaniti, Francesco
2008-06-01
Baurès et al. [Baurès, R., Benguigui, N., Amorim, M.-A., & Siegler, I. A. (2007). Intercepting free falling objects: Better use Occam's razor than internalize Newton's law. Vision Research, 47, 2982-2991] rejected the hypothesis that free-falling objects are intercepted using a predictive model of gravity. They argued instead for "a continuous guide for action timing" based on visual information updated till target capture. Here we show that their arguments are flawed, because they fail to consider the impact of sensori-motor delays on interception behaviour and the need for neural compensation of such delays. When intercepting a free-falling object, the delays can be overcome by a predictive model of the effects of gravity on target motion.
Reduction in Fall Rate in Dementia Managed Care Through Video Incident Review: Pilot Study
Netscher, George; Agrawal, Pulkit; Tabb Noyce, Lynn; Bayen, Alexandre
2017-01-01
Background Falls of individuals with dementia are frequent, dangerous, and costly. Early detection and access to the history of a fall is crucial for efficient care and secondary prevention in cognitively impaired individuals. However, most falls remain unwitnessed events. Furthermore, understanding why and how a fall occurred is a challenge. Video capture and secure transmission of real-world falls thus stands as a promising assistive tool. Objective The objective of this study was to analyze how continuous video monitoring and review of falls of individuals with dementia can support better quality of care. Methods A pilot observational study (July-September 2016) was carried out in a Californian memory care facility. Falls were video-captured (24×7), thanks to 43 wall-mounted cameras (deployed in all common areas and in 10 out of 40 private bedrooms of consenting residents and families). Video review was provided to facility staff, thanks to a customized mobile device app. The outcome measures were the count of residents’ falls happening in the video-covered areas, the acceptability of video recording, the analysis of video review, and video replay possibilities for care practice. Results Over 3 months, 16 falls were video-captured. A drop in fall rate was observed in the last month of the study. Acceptability was good. Video review enabled screening for the severity of falls and fall-related injuries. Video replay enabled identifying cognitive-behavioral deficiencies and environmental circumstances contributing to the fall. This allowed for secondary prevention in high-risk multi-faller individuals and for updated facility care policies regarding a safer living environment for all residents. Conclusions Video monitoring offers high potential to support conventional care in memory care facilities. PMID:29042342
Virtually Exploring A Pillar Of Experimental Physics: The Hertz Experiment
NASA Astrophysics Data System (ADS)
Bonanno, A.; Sapia, P.; Camarca, M.; Oliva, A.
2008-05-01
In the present work we report on the implementation and early assessment of a multimedia learning object, developed using the Java programming language, which also integrates in a creative way some internet freely available educational resources, intended to support the teaching/learning process of the historical Hertz experiment.
Terminal Velocity of a Shuttlecock in Vertical Fall.
ERIC Educational Resources Information Center
Peastrel, Mark; And Others
1980-01-01
Describes a straightforward vertical fall experiment using a badminton shuttlecock, a tape measure, and a millisecond timer. The effects of air resistance are important and directly measurable. The experimental data best fit a predictive model which assumes a resistive force quadratic in the instantaneous speed of the falling object. (GS)
Free fall and the equivalence principle revisited
NASA Astrophysics Data System (ADS)
Pendrill, Ann-Marie
2017-11-01
Free fall is commonly discussed as an example of the equivalence principle, in the context of a homogeneous gravitational field, which is a reasonable approximation for small test masses falling moderate distances. Newton’s law of gravity provides a generalisation to larger distances, and also brings in an inhomogeneity in the gravitational field. In addition, Newton’s third law of action and reaction causes the Earth to accelerate towards the falling object, bringing in a mass dependence in the time required for an object to reach ground—in spite of the equivalence between inertial and gravitational mass. These aspects are rarely discussed in textbooks when the motion of everyday objects are discussed. Although these effects are extremely small, it may still be important for teachers to make assumptions and approximations explicit, to be aware of small corrections, and also to be prepared to estimate their size. Even if the corrections are not part of regular teaching, some students may reflect on them, and their questions deserve to be taken seriously.
Senden, R; Savelberg, H H C M; Grimm, B; Heyligers, I C; Meijer, K
2012-06-01
This study investigated whether the Tinetti scale, as a subjective measure for fall risk, is associated with objectively measured gait characteristics. It is studied whether gait parameters are different for groups that are stratified for fall risk using the Tinetti scale. Moreover, the discriminative power of gait parameters to classify elderly according to the Tinetti scale is investigated. Gait of 50 elderly with a Tinneti>24 and 50 elderly with a Tinetti≤24 was analyzed using acceleration-based gait analysis. Validated algorithms were used to derive spatio-temporal gait parameters, harmonic ratio, inter-stride amplitude variability and root mean square (RMS) from the accelerometer data. Clear differences in gait were found between the groups. All gait parameters correlated with the Tinetti scale (r-range: 0.20-0.73). Only walking speed, step length and RMS showed moderate to strong correlations and high discriminative power to classify elderly according to the Tinetti scale. It is concluded that subtle gait changes that have previously been related to fall risk are not captured by the subjective assessment. It is therefore worthwhile to include objective gait assessment in fall risk screening. Copyright © 2012 Elsevier B.V. All rights reserved.
Mertens, Alexander; Brandl, Christopher; Liu, Shan; Buecking, Benjamin; Bliemel, Christopher; Horst, Klemens; Weber, Christian David; Lichte, Philipp; Knobe, Matthias
2018-01-01
Background Prohibiting falls and fall-related injuries is a major challenge for health care systems worldwide, as a substantial proportion of falls occur in older adults who are previously known to be either frail or at high risk for falls. Hence, preventive measures are needed to educate and minimize the risk for falls rather than just minimize older adults’ fall risk. Health apps have the potential to address this problem, as they enable users to self-assess their individual fall risk. Objective The objective of this study was to identify product features of a fall prevention smartphone app, which increase or decrease users’ satisfaction. In addition, willingness to pay (WTP) was assessed to explore how much revenue such an app could generate. Methods A total of 96 participants completed an open self-selected Web-based survey. Participants answered various questions regarding health status, subjective and objective fall risk, and technical readiness. Seventeen predefined product features of a fall prevention smartphone app were evaluated twice: first, according to a functional (product feature is implemented in the app), and subsequently by a dysfunctional (product feature is not implemented in the app) question. On the basis of the combination of answers from these 2 questions, the product feature was assigned to a certain category (must-be, attractive, one-dimensional, indifferent, or questionable product feature). This method is widely used in user-oriented product development and captures users’ expectations of a product and how their satisfaction is influenced by the availability of individual product features. Results Five product features were identified to increase users’ acceptance, including (1) a checklist of typical tripping hazards, (2) an emergency guideline in case of a fall, (3) description of exercises and integrated workout plans that decrease the risk of falling, (4) inclusion of a continuous workout program, and (5) cost coverage by health insurer. Participants’ WTP was assessed after all 17 product features were rated and revealed a median monthly payment WTP rate of €5.00 (interquartile range 10.00). Conclusions The results show various motivating product features that should be incorporated into a fall prevention smartphone app. Results reveal aspects that fall prevention and intervention designers should keep in mind to encourage individuals to start joining their program and facilitate long-term user engagement, resulting in a greater interest in fall risk prevention. PMID:29588268
Perceived object stability depends on multisensory estimates of gravity.
Barnett-Cowan, Michael; Fleming, Roland W; Singh, Manish; Bülthoff, Heinrich H
2011-04-27
How does the brain estimate object stability? Objects fall over when the gravity-projected centre-of-mass lies outside the point or area of support. To estimate an object's stability visually, the brain must integrate information across the shape and compare its orientation to gravity. When observers lie on their sides, gravity is perceived as tilted toward body orientation, consistent with a representation of gravity derived from multisensory information. We exploited this to test whether vestibular and kinesthetic information affect this visual task or whether the brain estimates object stability solely from visual information. In three body orientations, participants viewed images of objects close to a table edge. We measured the critical angle at which each object appeared equally likely to fall over or right itself. Perceived gravity was measured using the subjective visual vertical. The results show that the perceived critical angle was significantly biased in the same direction as the subjective visual vertical (i.e., towards the multisensory estimate of gravity). Our results rule out a general explanation that the brain depends solely on visual heuristics and assumptions about object stability. Instead, they suggest that multisensory estimates of gravity govern the perceived stability of objects, resulting in objects appearing more stable than they are when the head is tilted in the same direction in which they fall.
University of Washington Mobile Planetarium: Bringing HST Science to Seattle Public Schools
NASA Astrophysics Data System (ADS)
Gailey, Justin; Fraiser, O.; Rosenfield, P.; Byler, E.; Wisniewski, J. P.
2013-01-01
Digital planetariums are becoming mainstays of astronomy education as projection technology prices fall and planetarium software becomes more powerful and more freely available. In 2010, the University of Washington upgraded their star-ball projector to a digital system that is powered by Microsoft Research’s WorldWide Telescope. To increase the number of underserved elementary and high school students the UW Astronomy department reaches, we obtained an HST education and public outreach grant to create lesson content, offset transportation costs to visit the UW planetarium for Seattle Public School students, and purchase a mobile planetarium to bring to public schools. We present a pilot program to test and evaluate the efficacy of the mobile planetarium in a high school setting.
Coordinate Families for the Schwarzschild Geometry Based on Radial Timelike Geodesics
NASA Technical Reports Server (NTRS)
Finch, Tehani K.
2015-01-01
We explore the connections between various coordinate systems associated with observersmoving inwardly along radial geodesics in the Schwarzschild geometry. Painleve-Gullstrand (PG) time is adapted to freely falling observers dropped from rest from infinity; Lake-Martel-Poisson (LMP) time coordinates are adapted to observers who start at infinity with non-zero initial inward velocity; Gautreau-Hoffmann time coordinates are adapted to observers dropped from rest from a finite distance from the black hole horizon.We construct from these an LMP family and a proper-time family of time coordinates, the intersection of which is PG time. We demonstrate that these coordinate families are distinct, but related, one-parameter generalizations of PG time, and show linkage to Lemaître coordinates as well.
NASA Astrophysics Data System (ADS)
van Hecke, Martin
2013-03-01
All around us, things are falling apart. The foam on our cappuccinos appears solid, but gentle stirring irreversibly changes its shape. Skin, a biological fiber network, is firm when you pinch it, but soft under light touch. Sand mimics a solid when we walk on the beach but a liquid when we pour it out of our shoes. Crucially, a marginal point separates the rigid or jammed state from the mechanical vacuum (freely flowing) state - at their marginal points, soft materials are neither solid nor liquid. Here I will show how the marginal point gives birth to a third sector of soft matter physics: intrinsically nonlinear mechanics. I will illustrate this with shock waves in weakly compressed granular media, the nonlinear rheology of foams, and the nonlinear mechanics of weakly connected elastic networks.
MacDonald, Megan; Lipscomb, Shannon; McClelland, Megan M.; Duncan, Rob; Becker, Derek; Anderson, Kim; Kile, Molly
2017-01-01
Purpose The purpose was to examine specific linkages between early visual-motor integration skills and executive function, as well as between early object manipulation skills and social behaviors in the classroom over the preschool year. Method 92 children between the ages of 3–5 years old (mean age 4.31 years) were recruited to participate. Comprehensive measures of visual motor integration skills, object manipulation skills, executive function and social behaviors were administered in the fall and spring of the preschool year. Results Our findings indicated that children who had better visual-motor integration skills in the fall had better executive function scores, (B = .47 [.20], p < .05, β = .27) in the spring of the preschool year after controlling for age, gender, Head-Start status, and site location, but not after controlling for children’s baseline levels of executive function. In addition, children who demonstrated better object-manipulation skills in the fall showed significantly stronger social behavior in their classrooms (as rated by teachers) in the spring, including more self-control, (B −.03 [.00], p < .05, β = .40), more cooperation, (B = .02 [.01], p < .05, β = .28), and less externalizing/hyperactivity, (B = −.02 [.01], p < .05, β = −.28) after controlling for social behavior in the fall and other covariates. Conclusion Children’s visual motor integration and object manipulation skills in the fall have modest to moderate relations with executive function and social behaviors later in the preschool year. These findings have implications for early learning initiatives and school readiness. PMID:27732149
Development of a Fall-Risk Self-Assessment for Community-Dwelling Seniors
Vivrette, Rebecca L.; Rubenstein, Laurence Z.; Martin, Jennifer L.; Josephson, Karen R.; Kramer, B. Josea
2012-01-01
Objective To determine seniors’ beliefs about falls and design a fall-risk self-assessment and educational materials to promote early identification of evidence-based fall risks and encourage prevention behaviors. Methods Focus groups with community-dwelling seniors, conducted in two phases to identify perceptions about fall risks and risk reduction and to assess face validity of the fall-risk self-assessment and acceptability of educational materials. Results Lay perception of fall risks was in general concordance with evidence-based research. Maintaining independence and positive tone were perceived as key motivators for fall prevention. Seniors intended to use information in the educational tool to stimulate discussions about falls with health care providers. Implications An evidence-based, educational fall-risk self-assessment acceptable to older adults can build on existing lay knowledge about fall risks and perception that falls are a relevant problem and can educate seniors about their specific risks and how to minimize them. PMID:21285473
The Equivalence Principle Comes to School--Falling Objects and Other Middle School Investigations
ERIC Educational Resources Information Center
Pendrill, Ann-Marie; Ekström, Peter; Hansson, Lena; Mars, Patrik; Ouattara, Lassana; Ryan, Ulrika
2014-01-01
Comparing two objects falling together is a small-scale version of Galileo's classical experiment, demonstrating the equivalence between gravitational and inertial mass. We present here investigations by a group of ten-year-olds, who used iPads to record the drops. The movie recordings were essential in the follow-up discussions, enabling the…
Steel Spheres and Skydiver--Terminal Velocity
ERIC Educational Resources Information Center
Costa Leme, J.; Moura, C.; Costa, Cintia
2009-01-01
This paper describes the use of open source video analysis software in the study of the relationship between the velocity of falling objects and time. We discuss an experiment in which a steel sphere falls in a container filled with two immiscible liquids. The motion is similar to that of a skydiver falling through air.
Clinical prediction of fall risk and white matter abnormalities: a diffusion tensor imaging study
USDA-ARS?s Scientific Manuscript database
The Tinetti scale is a simple clinical tool designed to predict risk of falling by focusing on gait and stance impairment in elderly persons. Gait impairment is also associated with white matter (WM) abnormalities. Objective: To test the hypothesis that elderly subjects at risk for falling, as deter...
Mirelman, Anat; Herman, Talia; Brozgol, Marina; Dorfman, Moran; Sprecher, Elliot; Schweiger, Avraham; Giladi, Nir; Hausdorff, Jeffrey M
2012-01-01
Recent findings suggest that executive function (EF) plays a critical role in the regulation of gait in older adults, especially under complex and challenging conditions, and that EF deficits may, therefore, contribute to fall risk. The objective of this study was to evaluate if reduced EF is a risk factor for future falls over the course of 5 years of follow-up. Secondary objectives were to assess whether single and dual task walking abilities, an alternative window into EF, were associated with fall risk. We longitudinally followed 256 community-living older adults (age: 76.4±4.5 yrs; 61% women) who were dementia free and had good mobility upon entrance into the study. At baseline, a computerized cognitive battery generated an index of EF, attention, a closely related construct, and other cognitive domains. Gait was assessed during single and dual task conditions. Falls data were collected prospectively using monthly calendars. Negative binomial regression quantified risk ratios (RR). After adjusting for age, gender and the number of falls in the year prior to the study, only the EF index (RR: .85; CI: .74-.98, p = .021), the attention index (RR: .84; CI: .75-.94, p = .002) and dual tasking gait variability (RR: 1.11; CI: 1.01-1.23; p = .027) were associated with future fall risk. Other cognitive function measures were not related to falls. Survival analyses indicated that subjects with the lowest EF scores were more likely to fall sooner and more likely to experience multiple falls during the 66 months of follow-up (p<0.02). These findings demonstrate that among community-living older adults, the risk of future falls was predicted by performance on EF and attention tests conducted 5 years earlier. The present results link falls among older adults to cognition, indicating that screening EF will likely enhance fall risk assessment, and that treatment of EF may reduce fall risk.
Hauser, Robert A.; Heritier, Stephane; Rowse, Gerald J.; Hewitt, L. Arthur; Isaacson, Stuart H.
2016-01-01
Objectives Droxidopa is a prodrug of norepinephrine indicated for the treatment of orthostatic dizziness, lightheadedness, or the “feeling that you are about to black out” in adult patients with symptomatic neurogenic orthostatic hypotension caused by primary autonomic failure including Parkinson disease (PD). The objective of this study was to compare fall rates in PD patients with symptomatic neurogenic orthostatic hypotension randomized to droxidopa or placebo. Methods Study NOH306 was a 10-week, phase 3, randomized, placebo-controlled, double-blind trial of droxidopa in PD patients with symptomatic neurogenic orthostatic hypotension that included assessments of falls as a key secondary end point. In this report, the principal analysis consisted of a comparison of the rate of patient-reported falls from randomization to end of study in droxidopa versus placebo groups. Results A total of 225 patients were randomized; 222 patients were included in the safety analyses, and 197 patients provided efficacy data and were included in the falls analyses. The 92 droxidopa patients reported 308 falls, and the 105 placebo patients reported 908 falls. In the droxidopa group, the fall rate was 0.4 falls per patient-week; in the placebo group, the rate was 1.05 falls per patient-week (prespecified Wilcoxon rank sum P = 0.704; post hoc Poisson-inverse Gaussian test P = 0.014), yielding a relative risk reduction of 77% using the Poisson-inverse Gaussian model. Fall-related injuries occurred in 16.7% of droxidopa-treated patients and 26.9% of placebo-treated patients. Conclusions Treatment with droxidopa appears to reduce falls in PD patients with symptomatic neurogenic orthostatic hypotension, but this finding must be confirmed. PMID:27332626
Playground Exploration: An Opportunity for Incidental Learning of Mechanical Principles
ERIC Educational Resources Information Center
Lyons, Brian
2005-01-01
Play involves unstructured activity that is freely entered into and intrinsically rewarding. When children engage in play there is little intentional learning. There are no lesson plans. There are no daily objectives or specific learning outcomes. Incidental learning can cause relatively permanent changes in the way one thinks; accidental learning…
A Naive Bayes Approach for Converging Learning Objects with Open Educational Resources
ERIC Educational Resources Information Center
Sabitha, A. Sai; Mehrotra, Deepti; Bansal, Abhay; Sharma, B. K.
2016-01-01
Open educational resources (OER) are digitised material freely available to the students and self learners. Many institutions had initiated in incorporating these OERs in their higher educational system, to improve the quality of teaching and learning. These resources promote individualised study, collaborative learning. If they are coupled with…
ERIC Educational Resources Information Center
Gsponer, Andre
2009-01-01
The objective of this introduction to Colombeau algebras of generalized functions (in which distributions can be freely multiplied) is to explain in elementary terms the essential concepts necessary for their application to basic nonlinear problems in classical physics. Examples are given in hydrodynamics and electrodynamics. The problem of the…
Measurement of the Length of an Optical Trap
NASA Technical Reports Server (NTRS)
Wrbanek, Susan Y.
2010-01-01
NASA Glenn has been involved in developing optical trapping and optical micromanipulation techniques in order to develop a tool that can be used to probe, characterize, and assemble nano and microscale materials to create microscale sensors for harsh flight environments. In order to be able to assemble a sensor or probe candidate sensor material, it is useful to know how far an optical trap can reach; that is, the distance beyond/below the stable trapping point through which an object will be drawn into the optical trap. Typically, to measure the distance over which an optical trap would influence matter in a horizontal (perpendicular to beam propagation) direction, it was common to hold an object in one optical trap, place a second optical trap a known distance away, turn off the first optical trap, and note if the object was moved into the second trap when it was turned on. The disadvantage of this technique is that it only gives information of trap influence distance in horizontal (x y) directions. No information about the distance of the influence of the trap is gained in the direction of propagation of the beam (the z direction). A method was developed to use a time-of-flight technique to determine the length along the propagation direction of an optical trap beam over which an object may be drawn into the optical trap. Test objects (polystyrene microspheres) were held in an optical trap in a water-filled sample chamber and raised to a pre-determined position near the top of the sample chamber. Next, the test objects were released by blocking the optical trap beam. The test objects were allowed to fall through the water for predetermined periods of time, at the end of which the trapping beam was unblocked. It was noted whether or not the test object returned to the optical trap or continued to fall. This determination of the length of an optical trap's influence by this manner assumes that the test object falls through the water in the sample chamber at terminal velocity for the duration of its fall, so that the distance of trap influence can be computed simply by: d = VTt, where d is the trap length (or distance of trap reach), VT is the terminal velocity of the test object, and t is the time interval over which the object is allowed to fall.
Passive control of a falling sphere by elliptic-shaped appendages
NASA Astrophysics Data System (ADS)
Lācis, Uǧis; Olivieri, Stefano; Mazzino, Andrea; Bagheri, Shervin
2017-03-01
The majority of investigations characterizing the motion of single or multiple particles in fluid flows consider canonical body shapes, such as spheres, cylinders, discs, etc. However, protrusions on bodies—either surface imperfections or appendages that serve a function—are ubiquitous in both nature and applications. In this work, we characterize how the dynamics of a sphere with an axis-symmetric wake is modified in the presence of thin three-dimensional elliptic-shaped protrusions. By investigating a wide range of three-dimensional appendages with different aspect ratios and lengths, we clearly show that the sphere with an appendage may robustly undergo an inverted-pendulum-like (IPL) instability. This means that the position of the appendage placed behind the sphere and aligned with the free-stream direction is unstable, similar to how an inverted pendulum is unstable under gravity. Due to this instability, nontrivial forces are generated on the body, leading to turn and drift, if the body is free to fall under gravity. Moreover, we identify the aspect ratio and length of the appendage that induces the largest side force on the sphere, and therefore also the largest drift for a freely falling body. Finally, we explain the physical mechanisms behind these observations in the context of the IPL instability, i.e., the balance between surface area of the appendage exposed to reversed flow in the wake and the surface area of the appendage exposed to fast free-stream flow.
Vada-Kovács, M
1996-01-01
Porcine biceps femoris strips of 10 cm original length were stretched by 50% and fixed within 1 hr post mortem then subjected to temperatures of 4 °, 15 ° or 36 °C until they attained their ultimate pH. Unrestrained control muscle strips, which were left to shorten freely, were similarly treated. Post-mortem metabolism (pH, R-value) and shortening were recorded; thereafter ultimate meat quality traits (pH, lightness, extraction and swelling of myofibrils) were determined. The rate of pH fall at 36 °C, as well as ATP breakdown at 36 and 4 °C, were significantly reduced by pre-rigor stretch. The relationship between R-value and pH indicated cold shortening at 4 °C. Myofibrils isolated from pre-rigor stretched muscle strips kept at 36 °C showed the most severe reduction of hydration capacity, while paleness remained below extreme values. However, pre-rigor stretched myofibrils - when stored at 4 °C - proved to be superior to shortened ones in their extractability and swelling.
MacDonald, Megan; Lipscomb, Shannon; McClelland, Megan M; Duncan, Rob; Becker, Derek; Anderson, Kim; Kile, Molly
2016-12-01
The purpose of this article was to examine specific linkages between early visual-motor integration skills and executive function, as well as between early object manipulation skills and social behaviors in the classroom during the preschool year. Ninety-two children aged 3 to 5 years old (M age = 4.31 years) were recruited to participate. Comprehensive measures of visual-motor integration skills, object manipulation skills, executive function, and social behaviors were administered in the fall and spring of the preschool year. Our findings indicated that children who had better visual-motor integration skills in the fall had better executive function scores (B = 0.47 [0.20], p < .05, β = .27) in the spring of the preschool year after controlling for age, gender, Head Start status, and site location, but not after controlling for children's baseline levels of executive function. In addition, children who demonstrated better object manipulation skills in the fall showed significantly stronger social behavior in their classrooms (as rated by teachers) in the spring, including more self-control (B - 0.03 [0.00], p < .05, β = .40), more cooperation (B = 0.02 [0.01], p < .05, β = .28), and less externalizing/hyperactivity (B = - 0.02 [0.01], p < .05, β = - .28) after controlling for social behavior in the fall and other covariates. Children's visual-motor integration and object manipulation skills in the fall have modest to moderate relations with executive function and social behaviors later in the preschool year. These findings have implications for early learning initiatives and school readiness.
Older women's responses and decisions after a fall: The work of getting "back to normal".
Bergeron, Caroline D; Friedman, Daniela B; Messias, DeAnne K Hilfinger; Spencer, S Melinda; Miller, Susan C
2016-12-01
In this descriptive qualitative research, we examined older women's responses and decisions after experiencing a fall. Falls were unexpected, sudden events that heightened these women's awareness of their physical, emotional, spiritual, and social independence. Interviewees reported assessing personal, physical, and emotional needs; feeling burdened by the extra work; trying to get back to normal; seeking and obtaining assistance and spiritual support; avoiding specific people, objects, and places; planning ahead; and putting the fall out of mind. Consideration of older women's post-fall responses and decisions should be incorporated into fall prevention and management programs, services, and clinical recommendations.
ERIC Educational Resources Information Center
Hawley, Helen
2009-01-01
Objective To explore what might encourage older people to exercise at home after falls rehabilitation. Design: Qualitative research methods were used based on a grounded theory approach, to provide insights into older adults' experiences following a fall, of both rehabilitation and home exercise. Setting: Community dwellings. Method: Nine…
Rasche, Peter; Mertens, Alexander; Bröhl, Christina; Theis, Sabine; Seinsch, Tobias; Wille, Matthias; Pape, Hans-Christoph; Knobe, Matthias
2017-01-01
Fall incidents are a major problem for patients and healthcare. The "Aachen Fall Prevention App" (AFPA) represents the first mobile Health (mHealth) application (app) empowering older patients (persons 50+ years) to self-assess and monitor their individual fall risk. Self-assessment is based on the "Aachen Fall Prevention Scale," which consists of three steps. First, patients answer ten standardized yes-no questions (positive criterion ≥ 5 "Yes" responses). Second, a ten-second test of free standing without compensatory movement is performed (positive criterion: compensatory movement). Finally, during the third step, patients rate their subjective fall risk on a 10-point Likert scale, based on the results of steps one and two. The purpose of this app is (1) to offer a low-threshold service through which individuals can independently monitor their individual fall risk and (2) to collect data about how a patient-centered mHealth app for fall risk assessment is used in the field. The results represent the first year of an ongoing field study. From December 2015 to December 2016, 197 persons downloaded the AFPA (iOS ™ and Android ™ ; free of charge). N = 111 of these persons voluntarily shared their data and thereby participated in the field study. Data from a final number of n = 79 persons were analyzed due to exclusion criteria (age, missing objective fall risk, missing self-assessment). The objective fall risk and the self-assessed subjective risk measured by the AFPA showed a significant positive relationship. The "Aachen Fall Prevention App" (AFPA) is an mHealth app released for iOS and Android. This field study revealed the AFPA as a promising tool to raise older adults' awareness of their individual fall risk by means of a low-threshold patient-driven fall risk assessment tool.
Intrinsic factors associated with pregnancy falls.
Wu, Xuefang; Yeoh, Han T
2014-10-01
Approximately 25% to 27% of women sustain a fall during pregnancy, and falls are associated with serious injuries and can affect pregnancy outcomes. The objective of the current study was to identify intrinsic factors associated with pregnancy that may contribute to women's increased risk of falls. A literature search (Medline and Pubmed) identified articles published between January 1980 and June 2013 that measured associations between pregnancy and fall risks, using an existing fall accident investigation framework. The results indicated that physiological, biomechanical, and psychological changes associated with pregnancy may influence the initiation, detection, and recovery phases of falls and increase the risk of falls in this population. Considering the logistic difficulties and ethnic concerns in recruiting pregnant women to participate in this investigation of fall risk factors, identification of these factors could establish effective fall prevention and intervention programs for pregnant women and improve birth outcomes. [Workplace Health Saf 2014;62(10):403-408.]. Copyright 2014, SLACK Incorporated.
Collado-Mateo, D; Gallego-Diaz, J M; Adsuar, J C; Domínguez-Muñoz, F J; Olivares, P R; Gusi, N
2015-01-01
To evaluate fear of falling, number of falls, and balance performance in women with FM and to examine the relationship between these variables and others, such as balance performance, quality of life, age, pain, and impact of fibromyalgia. A total of 240 women participated in this cross-sectional study. Of these, 125 had fibromyalgia. Several variables were assessed: age, fear of falling from 0 to 100, number of falls, body composition, balance performance, lower limb strength, health-related quality of life, and impact of fibromyalgia. Women with fibromyalgia reported more falls and more fear of falling. Fear of falling was associated with number of falls in the last year, stiffness, perceived balance problems, impact of FM, and HRQoL whereas the number of falls was related to fear of falling, balance performance with eyes closed, pain, tenderness to touch level, anxiety, self-reported balance problems, impact of FM, and HRQoL. FM has an impact on fear of falling, balance performance, and number of falls. Perceived balance problems seem to be more closely associated with fear of falling than objective balance performance.
Cognitive, perceptual and action-oriented representations of falling objects.
Zago, Myrka; Lacquaniti, Francesco
2005-01-01
We interact daily with moving objects. How accurate are our predictions about objects' motions? What sources of information do we use? These questions have received wide attention from a variety of different viewpoints. On one end of the spectrum are the ecological approaches assuming that all the information about the visual environment is present in the optic array, with no need to postulate conscious or unconscious representations. On the other end of the spectrum are the constructivist approaches assuming that a more or less accurate representation of the external world is built in the brain using explicit or implicit knowledge or memory besides sensory inputs. Representations can be related to naive physics or to context cue-heuristics or to the construction of internal copies of environmental invariants. We address the issue of prediction of objects' fall at different levels. Cognitive understanding and perceptual judgment of simple Newtonian dynamics can be surprisingly inaccurate. By contrast, motor interactions with falling objects are often very accurate. We argue that the pragmatic action-oriented behaviour and the perception-oriented behaviour may use different modes of operation and different levels of representation.
Prevalence of falls in elderly women
Vitor, Priscila Regina Rorato; de Oliveira, Ana Carolina Kovaleski; Kohler, Renan; Winter, Gabriele Regiane; Rodacki, Cintia; Krause, Maressa Priscila
2015-01-01
OBJECTIVE: To verify prevalence of falls and fear of falling, and to compare functional fitness among elderly women fallers and non-fallers. METHODS: Seventy-eight elderly women participated in this study. Cases of falls and the fear of falling were self-reported by the elderly women, while the functional fitness was measured by a set of functional tests. Mean and standard deviation were used to describe the sample. Independent t-test was used to compare functional fitness between groups. RESULTS: The prevalence of falls in this sample was 32.4%. Among women fallers, 40% self-reported a high fear of falling. CONCLUSION: It is recommended that functional and resistance exercises are included in the preventive strategies for reducing risk factors for falls and its determinants in elderly women. Level of Evidence II, Prognostic-Prospective Study. PMID:26207095
Fall detection of elderly through floor vibrations and sound.
Litvak, Dima; Zigel, Yaniv; Gannot, Israel
2008-01-01
Falls are very prevalent among the elderly especially in their home. The statistics show that approximately one in every three adults 65 years old or older falls each year. Almost 30% of those falls result in serious injuries. Studies have shown that the medical outcome of a fall is largely dependent upon the response and rescue time. Therefore, reliable and immediate fall detection system is important so that adequate medical support could be delivered. We have developed a unique and inexpensive solution that does not require subjects to wear anything. The solution is based on floor vibration and acoustic sensing, and uses a pattern recognition algorithm to discriminate between human or inanimate object fall events. Using the proposed system we can detect human falls with a sensitivity of 95% and specificity of 95%.
Finch, Caroline F; Hill, Keith D; Haines, Terry P; Clemson, Lindy; Thomas, Margaret; Thompson, Catherine
2010-01-01
Background Falls are a significant threat to the safety, health and independence of older citizens. Despite the now substantial evidence about effective falls prevention interventions, translation into falls reductions has not yet been fully realised. While the hip fracture rate is decreasing, the number and rate of fall-related hospital admissions among older people is increasing. The challenge now is to deliver the most effective interventions efficiently at a population level, and for these interventions to be taken up by older people. Objective To support the development, and evaluation of, effective falls prevention policy and practice in the state of Victoria, Australia. Methods The RE-AIM model (Reach, Efficacy, Adoption, Implementation, Maintenance) was used to identify strategies for an effective programme. Research objectives were developed to support the strategies. These include: (1) identification of subgroups of older people most frequently admitted to hospital for falls; (2) examining the acceptability of established falls interventions; (3) identification of factors that encourage and support relevant lifestyle changes; (4) identifying opportunities to incorporate confirmed interventions in existing programmes and services; (5) developing guidelines for sustainability. The research results will subsequently guide strategy details for the falls prevention plan. RE-AIM will provide the framework for the evaluation structure. Outcome measures Measures to monitor the implementation of the selected interventions will be determined for each intervention, based on the five key factors of the RE-AIM model. The overall effect of the falls prevention plan will be monitored by time series analysis of fall-related hospital admission rates for community-dwelling older people. PMID:21186224
Improved Training Method for Rapid Rehabilitation of Amputees
2012-03-01
amputees must be able to manage uneven terrain, crowded environments, stairs , ramps, and hills. The largest problem for a lower extremity amputee is...objective biomechanical variables that are causally related to the success or failure in avoiding a fall after a trip, objective tests to quantify...crowded environments, stairs , ramps, and hills. The key factor that limits the ability of amputees to achieve maximum functional capabilities is falls
Oguz, Semra; Demirbuken, Ilksan; Kavlak, Bahar; Acar, Gonul; Yurdalan, Saadet Ufuk; Polat, Mine Gulden
2017-10-01
The objective of our study was to investigate the relationship between objective balance, fear of falling, and perceived sense of balance (PSB) in stroke patients. Seventy patients aged 18-65 years with chronically developed hemiplegia or hemiparesis were enrolled in the study. Patients' objective balance scores, fear of falling, and PSB were obtained using the berg balance scale (BBS), the falls efficacy scale (FES), and a visual analog scale, respectively. The Standard Mini-Mental Examination was performed to exclude patients with mental disorders from the study. There was a moderate negative correlation between PSB and BBS scores (p = 0.001, ρ = -0.588); a strong negative correlation between BBS and FES scores (p = 0.001, ρ = -0.808); and a strong positive correlation between PSB and FES scores (p = 0.001, ρ = 0.714). We found that BBS scores had negative correlation with PBS scores in left hemiplegic patients while there was no any relationship between BBS and PBS scores in right hemiplegic patients. PSB assessment, besides the BBS, should be considered among the routine assessment methods that enable the rehabilitation team to be aware of patients' balance capacities.
Wireless inertial measurement of head kinematics in freely-moving rats
Pasquet, Matthieu O.; Tihy, Matthieu; Gourgeon, Aurélie; Pompili, Marco N.; Godsil, Bill P.; Léna, Clément; Dugué, Guillaume P.
2016-01-01
While miniature inertial sensors offer a promising means for precisely detecting, quantifying and classifying animal behaviors, versatile inertial sensing devices adapted for small, freely-moving laboratory animals are still lacking. We developed a standalone and cost-effective platform for performing high-rate wireless inertial measurements of head movements in rats. Our system is designed to enable real-time bidirectional communication between the headborne inertial sensing device and third party systems, which can be used for precise data timestamping and low-latency motion-triggered applications. We illustrate the usefulness of our system in diverse experimental situations. We show that our system can be used for precisely quantifying motor responses evoked by external stimuli, for characterizing head kinematics during normal behavior and for monitoring head posture under normal and pathological conditions obtained using unilateral vestibular lesions. We also introduce and validate a novel method for automatically quantifying behavioral freezing during Pavlovian fear conditioning experiments, which offers superior performance in terms of precision, temporal resolution and efficiency. Thus, this system precisely acquires movement information in freely-moving animals, and can enable objective and quantitative behavioral scoring methods in a wide variety of experimental situations. PMID:27767085
Black hole complementarity in gravity's rainbow
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gim, Yongwan; Kim, Wontae, E-mail: yongwan89@sogang.ac.kr, E-mail: wtkim@sogang.ac.kr
2015-05-01
To see how the gravity's rainbow works for black hole complementary, we evaluate the required energy for duplication of information in the context of black hole complementarity by calculating the critical value of the rainbow parameter in the certain class of the rainbow Schwarzschild black hole. The resultant energy can be written as the well-defined limit for the vanishing rainbow parameter which characterizes the deformation of the relativistic dispersion relation in the freely falling frame. It shows that the duplication of information in quantum mechanics could not be allowed below a certain critical value of the rainbow parameter; however, itmore » might be possible above the critical value of the rainbow parameter, so that the consistent formulation in our model requires additional constraints or any other resolutions for the latter case.« less
Coordinate Families for the Schwarzschild Geometry Based on Radial Timelike Geodesics
NASA Technical Reports Server (NTRS)
Finch, Tehani K.
2015-01-01
We explore the connections between various coordinate systems associated with observers moving inwardly along radial geodesics in the Schwarzschild geometry. Painleve-Gullstrand (PG) time is adapted to freely falling observers dropped from rest from in nity; Lake-Martel-Poisson (LMP) time coordinates are adapted to observers who start at in nity with non-zero initial inward velocity; Gautreau-Ho mann (GH) time coordinates are adapted to observers dropped from rest from a nite distance from the black hole horizon. We construct from these an LMP family and a propertime family of time coordinates, the intersection of which is PG time. We demonstrate that these coordinate families are distinct, but related, one-parameter generalizations of PG time, and show linkage to Lema^tre coordinates as well.
Liu-Ambrose, Teresa; Khan, Karim M; Eng, Janice J; Lord, SR; McKay, HA
2012-01-01
Background While the fear of falling is a common psychological consequence of falling, older adults who have not fallen also frequently report this fear. Fear of falling can lead to activity restriction that is self-imposed rather than due to actual physical impairments. Evidence suggests that exercise can significantly improve balance confidence, as measured by falls-related self-efficacy scales. However, there are no prospective reports that correlate change in balance confidence with changes in fall risk and physical abilities as induced by participating in a group-based exercise program. Objective The primary purpose of this prospective study was to examine the relationship between the change in balance confidence and the changes in fall risk and physical abilities in older women with confirmed low bone mass after 13 weeks of exercise participation. The secondary purpose of this study was to examine the relationship between the change in balance confidence and the change in physical activity level. Methods The sample comprised 98 women aged 75 to 85 years old women with low bone mass. Participants were randomly assigned to one of three groups: Resistance Training (n=32), Agility Training (n=34), and Stretching (sham) exercises (n=32). The 50-minute exercise classes for each study arm were held twice weekly at a local YMCA community centre. Results Both resistance training and agility training significantly improved balance confidence by 6% from baseline after 13 weeks. However, the change in balance confidence was only weakly correlated with improved general physical function and not significantly correlated with the changes in fall risk score, postural stability, gait speed, or physical activity level. As well, we observed balance confidence enhancement in the presence of increased fall risk or deterioration in physical abilities. Conclusions Two different types of exercise training improved balance confidence in older women with low bone mass. This change in balance confidence was significantly correlated with change in general physical function. Because of the observation of discordance between balance confidence change and changes in fall risk and physical abilities, those who design group-based exercise programs for community-dwelling older adults may wish to consider including an education component on factors that influence fear of falling. Objective changes in fall risk factors cannot be assumed to mirror change of fear of falling and physical abilities in older adults in the short-term. PMID:15477698
Fall Risk Assessment in Geriatric-Psychiatric Inpatients to Lower Events (FRAGILE).
Nanda, Sudip; Dey, Tanujit; Gulstrand, Rudolph E; Cudnik, Daniel; Haller, Harold S
2011-02-01
The objectives of this retrospective case-control study were to identify risk factors of falls in geriatric-psychiatric inpatients and develop a screening tool to accurately predict falls. The study sample consisted of 225 geriatric-psychiatric inpatients at a Midwestern referral facility. The sample included 136 inpatients who fell and a random stratified sample of 89 inpatients who did not fall. Data collected included age, gender, activities of daily living, and nursing parameters such as bathing assistance, bed height, use of bed rails, one-on-one observation, fall warning system, Conley Scale fall risk assessment, medical diagnosis, and medications. History of falls, impaired judgment, impaired gait, dizziness, delusions, delirium, chronic use of sedative or antipsychotic agents, and anticholinergic urinary bladder medications significantly increased fall risk. Alzheimer's disease, acute use of sedative or anti-psychotic agents, and depression reduced fall risk. A falls risk tool, Fall Risk Assessment in Geriatric-psychiatric Inpatients to Lower Events (FRAGILE), was developed for assessment and risk stratification with new diagnoses or medications. Copyright 2011, SLACK Incorporated.
Assessment of Fall Characteristics From Depth Sensor Videos.
O'Connor, Jennifer J; Phillips, Lorraine J; Folarinde, Bunmi; Alexander, Gregory L; Rantz, Marilyn
2017-07-01
Falls are a major source of death and disability in older adults; little data, however, are available about the etiology of falls in community-dwelling older adults. Sensor systems installed in independent and assisted living residences of 105 older adults participating in an ongoing technology study were programmed to record live videos of probable fall events. Sixty-four fall video segments from 19 individuals were viewed and rated using the Falls Video Assessment Questionnaire. Raters identified that 56% (n = 36) of falls were due to an incorrect shift of body weight and 27% (n = 17) from losing support of an external object, such as an unlocked wheelchair or rolling walker. In 60% of falls, mobility aids were in the room or in use at the time of the fall. Use of environmentally embedded sensors provides a mechanism for real-time fall detection and, ultimately, may supply information to clinicians for fall prevention interventions. [Journal of Gerontological Nursing, 43(7), 13-19.]. Copyright 2017, SLACK Incorporated.
ERIC Educational Resources Information Center
Simoson, Andrew; Wentzky, Bethany
2011-01-01
Freely rising air bubbles in water sometimes assume the shape of a spherical cap, a shape also known as the "big bubble". Is it possible to find some objective function involving a combination of a bubble's attributes for which the big bubble is the optimal shape? Following the basic idea of the definite integral, we define a bubble's surface as…
Spatial Relational Memory in 9-Month-Old Macaque Monkeys
ERIC Educational Resources Information Center
Lavenex, Pierre; Lavenex, Pamela Banta
2006-01-01
This experiment assesses spatial and nonspatial relational memory in freely moving 9-mo-old and adult (11-13-yr-old) macaque monkeys ("Macaca mulatta"). We tested the use of proximal landmarks, two different objects placed at the center of an open-field arena, as conditional cues allowing monkeys to predict the location of food rewards hidden in…
"SMALLab": Virtual Geology Studies Using Embodied Learning with Motion, Sound, and Graphics
ERIC Educational Resources Information Center
Johnson-Glenberg, Mina C.; Birchfield, David; Usyal, Sibel
2009-01-01
We present a new and innovative interface that allows the learner's body to move freely in a multimodal learning environment. The Situated Multimedia Arts Learning Laboratory ("SMALLab") uses 3D object tracking, real time graphics, and surround-sound to enhance embodied learning. Our hypothesis is that optimal learning and retention occur when…
USDA-ARS?s Scientific Manuscript database
Minimizing the effects of restraint and human interaction on the endocrine physiology of animals is essential for collection of accurate physiological measurements. Our objective was to compare stress-induced cortisol (CORT) and noradrenalin (NorA) responses in automated versus manual blood sampling...
AGU Career Center attracts hundreds of Fall Meeting attendees
NASA Astrophysics Data System (ADS)
Cooper, Paul
2012-02-01
The poster hall of the 2011 AGU Fall Meeting was the venue not only for scientific discussion and exchange of ideas—Fall Meeting attendees also explored new career opportunities and received career advice at AGU's Career Center. For many years, recruiters and hiring managers have found ideal candidates for open positions during the AGU Fall Meeting through the Career Center. Last year was no exception: Recruiters browsed resumés, visited posters, and attended talks to find talented individuals to interview during the week. In addition, hundreds of meeting attendees looking for a new job or a postdoc position visited the Career Center and checked the online AGU Career Center job board to request interviews. Career counselor Alaina Levine of Quantum Success Solutions gave private one-on-one career advice to 47 meeting attendees, making sure that each individual she counseled left the session with clearer career objectives and tactics to bring these objectives to fruition.
Retraction: New aspects of photon propagation in expanding universes
NASA Astrophysics Data System (ADS)
Fahr, H.-J.; Heyl, M.
2017-12-01
According to present cosmological views the energy density of CMB (Cosmic Microwave Background) photons, freely propagating through the expanding cosmos, varies proportional to 1/S^4 with S being the scale factor of the universe. This behavior is expected, because General Theory of Relativity, in application to FLRW- (Friedmann-Lemaitre-Robertson-Walker) cosmological universes, leads to the conclusion that the photon wavelengths increase during their free passage through the spacetime metrics of the universe by the same factor as does the scale factor S. This appears to be a reasonable explanation for the presently observed Planckian CMB spectrum with its actual temperature of about 2.7 K, while at the time of its origin after the last scattering during the recombination phase its temperature should have been about 3000 K, at an epoch of about 380 ky after the Big Bang, when the scale of the universe S_r was smaller by roughly a factor of S/S_r = 1+z_r = 1100 compared to the present scale S = S_0 of the universe. In this paper we start from putting the question whether the scale-behavior of the CMB energy density that enters the energy-momentum tensor of the field equations describing the expanding universe is really falling off like 1/S^4 and, if in fact a deviation from a behavior according to 1/S^4 would occur, why do we nevertheless presently observe a CMB energy density which appears to be in accordance with such a 1/S^4-scaling? This question arises from another basic and fundamental question, namely: Can we really assume that the wavelength of the freely propagating photon during its travel all the way along its light geodetic is permanently affected by the expansion of the universe, i.e continuously recognizes the expansion of the cosmic scale S? With other words: Do freely propagating photons ........
ERIC Educational Resources Information Center
Venkadasalam, Vaunam P.; Ganea, Patricia A.
2018-01-01
This study examined whether children 4- and 5-years-old (N = 156) can revise a physical science misconception from different types of picture books. A realistic fiction book and informational book with identical images matched in word count and reading difficulty level were compared to a control book about plants. In the pretest and posttest,…
Reducing Floor Impact Vibration and Sound Using a Momentum Exchange Impact Damper
NASA Astrophysics Data System (ADS)
Son, Lovely; Kawachi, Makoto; Matsuhisa, Hiroshi; Utsuno, Hideo
This paper deals with reducing floor impact vibration and sound by using a momentum exchange impact damper. The impact damper consists of a spring and a mass that is contact with the floor. When a falling object collides with the floor, the floor interacts with the damper mass, and the momentum of the falling object is transferred to the damper. In this works a computational model is formulated to simulate dynamic floor vibration induced by impact. The floor vibration is simulated for various sized damper masses. A proof-of-concept experimental apparatus was fabricated to represent a floor with an impact damper. This example system consists of an acrylic plate, a ball for falling object, and an impact damper. A comparison between simulated and experimental results were in good agreement in suggesting that the proposed impact damper is effective at reducing floor impact vibration and sound by 25% and 63%, respectively.
Mirelman, Anat; Herman, Talia; Brozgol, Marina; Dorfman, Moran; Sprecher, Elliot; Schweiger, Avraham; Giladi, Nir; Hausdorff, Jeffrey M.
2012-01-01
Background Recent findings suggest that executive function (EF) plays a critical role in the regulation of gait in older adults, especially under complex and challenging conditions, and that EF deficits may, therefore, contribute to fall risk. The objective of this study was to evaluate if reduced EF is a risk factor for future falls over the course of 5 years of follow-up. Secondary objectives were to assess whether single and dual task walking abilities, an alternative window into EF, were associated with fall risk. Methodology/Main Results We longitudinally followed 256 community-living older adults (age: 76.4±4.5 yrs; 61% women) who were dementia free and had good mobility upon entrance into the study. At baseline, a computerized cognitive battery generated an index of EF, attention, a closely related construct, and other cognitive domains. Gait was assessed during single and dual task conditions. Falls data were collected prospectively using monthly calendars. Negative binomial regression quantified risk ratios (RR). After adjusting for age, gender and the number of falls in the year prior to the study, only the EF index (RR: .85; CI: .74–.98, p = .021), the attention index (RR: .84; CI: .75–.94, p = .002) and dual tasking gait variability (RR: 1.11; CI: 1.01–1.23; p = .027) were associated with future fall risk. Other cognitive function measures were not related to falls. Survival analyses indicated that subjects with the lowest EF scores were more likely to fall sooner and more likely to experience multiple falls during the 66 months of follow-up (p<0.02). Conclusions/Significance These findings demonstrate that among community-living older adults, the risk of future falls was predicted by performance on EF and attention tests conducted 5 years earlier. The present results link falls among older adults to cognition, indicating that screening EF will likely enhance fall risk assessment, and that treatment of EF may reduce fall risk. PMID:22768271
Iwarsson, Susanne; Horstmann, Vibeke; Carlsson, Gunilla; Oswald, Frank; Wahl, Hans-Werner
2009-06-01
To test the hypotheses that the empirical consideration of objective person-environment fit in the home environment is a stronger predictor of indoor falls among older adults than the assessment of environmental barriers only, and that perceived aspects of home play a role as predictors for falls. Survey study with data collection at home visits, followed up by self-reports about falls at home visits one year later. Urban districts in Sweden, Germany, Latvia. Eight hundred and thirty-four single-living, older adults (75-89 years), in ordinary housing. An assessment of objective person-environment fit in the home environment (housing enabler), a self-rating of the perceived home environment (usability in my home) and retrospective self-reports on indoor falls. The participants reporting falls tended to be frailer than the non-fallers. The number of environmental barriers in the home was similar for the fallers and non-fallers; the magnitude of person-environment fit problems was higher among the fallers. The person-environment fit problem variable was a stronger fall predictor (odds ratio (OR) = 1.025; P=0.037) than number of environmental barriers (n.s.), even after controlling for confounders. Fallers also experienced lower usability of their home. The results suggest that much of the inconclusiveness of the data in the relationship between environmental hazards and falls in the previous falls literature could be due to the neglect of person-environment fit assessment. The effectiveness of environmental interventions based on the notion of person-environment fit compared with traditional home hazard checklists remains to be tested.
A freely-moving monkey treadmill model
NASA Astrophysics Data System (ADS)
Foster, Justin D.; Nuyujukian, Paul; Freifeld, Oren; Gao, Hua; Walker, Ross; Ryu, Stephen I.; Meng, Teresa H.; Murmann, Boris; Black, Michael J.; Shenoy, Krishna V.
2014-08-01
Objective. Motor neuroscience and brain-machine interface (BMI) design is based on examining how the brain controls voluntary movement, typically by recording neural activity and behavior from animal models. Recording technologies used with these animal models have traditionally limited the range of behaviors that can be studied, and thus the generality of science and engineering research. We aim to design a freely-moving animal model using neural and behavioral recording technologies that do not constrain movement. Approach. We have established a freely-moving rhesus monkey model employing technology that transmits neural activity from an intracortical array using a head-mounted device and records behavior through computer vision using markerless motion capture. We demonstrate the flexibility and utility of this new monkey model, including the first recordings from motor cortex while rhesus monkeys walk quadrupedally on a treadmill. Main results. Using this monkey model, we show that multi-unit threshold-crossing neural activity encodes the phase of walking and that the average firing rate of the threshold crossings covaries with the speed of individual steps. On a population level, we find that neural state-space trajectories of walking at different speeds have similar rotational dynamics in some dimensions that evolve at the step rate of walking, yet robustly separate by speed in other state-space dimensions. Significance. Freely-moving animal models may allow neuroscientists to examine a wider range of behaviors and can provide a flexible experimental paradigm for examining the neural mechanisms that underlie movement generation across behaviors and environments. For BMIs, freely-moving animal models have the potential to aid prosthetic design by examining how neural encoding changes with posture, environment and other real-world context changes. Understanding this new realm of behavior in more naturalistic settings is essential for overall progress of basic motor neuroscience and for the successful translation of BMIs to people with paralysis.
Learning about Gravity I. Free Fall: A Guide for Teachers and Curriculum Developers
ERIC Educational Resources Information Center
Kavanagh, Claudine; Sneider, Cary
2007-01-01
This article is the first of a two-part review of research on children's and adults understanding of gravity and on how best to teach gravity concepts to students and teachers. This first article concerns free fall--how and why objects fall when they are dropped. The review begins with a brief historical sketch of how these ideas were developed in…
Connor, William P.; Bjornn, Theodore C.; Burge, Howard L.; Garcia, Aaron P.; Rondorf, Dennis W.
1997-01-01
The objectives of this segment of our study were to (1) describe the early life history characteristics of naturally produced subyearling fall chinook salmon in the Snake and Clearwater rivers, and (2) estimate survival for juvenile fall chinook salmon emigrating from the Snake and Clearwater rivers to the tail race of Lower Granite Dam.
OpenCFU, a new free and open-source software to count cell colonies and other circular objects.
Geissmann, Quentin
2013-01-01
Counting circular objects such as cell colonies is an important source of information for biologists. Although this task is often time-consuming and subjective, it is still predominantly performed manually. The aim of the present work is to provide a new tool to enumerate circular objects from digital pictures and video streams. Here, I demonstrate that the created program, OpenCFU, is very robust, accurate and fast. In addition, it provides control over the processing parameters and is implemented in an intuitive and modern interface. OpenCFU is a cross-platform and open-source software freely available at http://opencfu.sourceforge.net.
"Above the Slough of Despond": Weylean invariantism and quantum physics
NASA Astrophysics Data System (ADS)
Toader, Iulian D.
2018-02-01
The pursuit of scientific objectivity turned physical theories into systems of symbols or, as Weyl also put it sometimes, into symbolic constructions. What characterizes such constructions, at least in part, is a certain type of Begriffsbildung, according to which scientific concepts are freely created by the mind, i.e., implicitly defined via fundamental theoretical postulates (Toader, 2013). This idea, inspired by Hilbert, together with an approach to understanding influenced by Husserl, led Weyl to a form of skepticism about science, according to which if objectivity could be attained, understanding would thereby be sacrificed; and if understanding were to be pursued, this would render objectivity unattainable (Toader, 2011).
Design of an algorithm for autonomous docking with a freely tumbling target
NASA Astrophysics Data System (ADS)
Nolet, Simon; Kong, Edmund; Miller, David W.
2005-05-01
For complex unmanned docking missions, limited communication bandwidth and delays do not allow ground operators to have immediate access to all real-time state information and hence prevent them from playing an active role in the control loop. Advanced control algorithms are needed to make mission critical decisions to ensure safety of both spacecraft during close proximity maneuvers. This is especially true when unexpected contingencies occur. These algorithms will enable multiple space missions, including servicing of damaged spacecraft and missions to Mars. A key characteristic of spacecraft servicing missions is that the target spacecraft is likely to be freely tumbling due to various mechanical failures or fuel depletion. Very few technical references in the literature can be found on autonomous docking with a freely tumbling target and very few such maneuvers have been attempted. The MIT Space Systems Laboratory (SSL) is currently performing research on the subject. The objective of this research is to develop a control architecture that will enable safe and fuel-efficient docking of a thruster based spacecraft with a freely tumbling target in presence of obstacles and contingencies. The approach is to identify, select and implement state estimation, fault detection, isolation and recovery, optimal path planning and thruster management algorithms that, once properly integrated, can accomplish such a maneuver autonomously. Simulations and demonstrations on the SPHERES testbed developed by the MIT SSL will be executed to assess the performance of different combinations of algorithms. To date, experiments have been carried out at the MIT SSL 2-D Laboratory and at the NASA Marshall Space Flight Center (MSFC) flat floor.
Grasping objects autonomously in simulated KC-135 zero-g
NASA Technical Reports Server (NTRS)
Norsworthy, Robert S.
1994-01-01
The KC-135 aircraft was chosen for simulated zero gravity testing of the Extravehicular Activity Helper/retriever (EVAHR). A software simulation of the EVAHR hardware, KC-135 flight dynamics, collision detection and grasp inpact dynamics has been developed to integrate and test the EVAHR software prior to flight testing on the KC-135. The EVAHR software will perform target pose estimation, tracking, and motion estimation for rigid, freely rotating, polyhedral objects. Manipulator grasp planning and trajectory control software has also been developed to grasp targets while avoiding collisions.
Dynamics of place, boundary and object encoding in rat anterior claustrum
Jankowski, Maciej M.; O’Mara, Shane M.
2015-01-01
Discrete populations of brain cells signal differing types of spatial information. These “spatial cells” are largely confined to a closely-connected network of sites. We describe here, for the first time, cells in the anterior claustrum of the freely-moving rat encoding place, boundary and object information. This novel claustral spatial signal potentially directly modulates a wide variety of anterior cortical regions. We hypothesize that one of the functions of the claustrum is to provide information about body position, boundaries and landmark information, enabling dynamic control of behavior. PMID:26557060
Toward an Online Community of Educators: The Modular Curriculum for Hydrologic Advancement (MOCHA)
NASA Astrophysics Data System (ADS)
Kelleher, C.; Wagener, T.; Gooseff, M. N.; Gregg, S.; McGlynn, B. L.; Sharma, P.; Meixner, T.; Marshall, L. A.; McGuire, K. J.; Weiler, M.
2009-12-01
The field of hydrology encompasses a wide range of departments and disciplines, ranging from civil engineering to geography to geosciences. As a consequence, in-class hydrology education is often strongly biased towards the background of a single instructor, limiting the educational experience of the students and not allowing for a holistic approach to hydrology education. Recently established, the Modular Curriculum for Hydrologic Advancement (MOCHA) creates an online community of hydrologists from a range of backgrounds and disciplines to define the boundaries of an unbiased hydrology education and to jointly develop resources to overcome previous instructional limitations (http://www.mocha.psu.edu/). Our first objective is to create an evolving core curriculum for hydrology education freely available to, developed, evolved and reviewed by the worldwide hydrologic community. On a larger scale, we hope to raise the standard of hydrology education and to foster international collaboration and exchange. Our work began with an initial survey including over 100 hydrology educators to assess the state of current hydrology education. Based on the survey results, the MOCHA project was designed and implemented, and initial teaching material and pedagogical guidelines for good practice in teaching were prepared. This past fall and spring, we piloted the website and teaching material across several universities. The web-based MOCHA project has recently been opened to solicit contributions from the global hydrology community. Our presentation will focus on the overall vision behind MOCHA, lessons learned from our initial piloting, and current steps to achieve our vision.
Mitkidis, Panagiotis; Roepstorff, Andreas
2016-01-01
A variety of joint action studies show that people tend to fall into synchronous behavior with others participating in the same task, and that such synchronization is beneficial, leading to greater rapport, satisfaction, and performance. It has been noted that many of these task environments require simple interactions that involve little planning of action coordination toward a shared goal. The present study utilized a complex joint construction task in which dyads were instructed to build model cars while their hand movements and heart rates were measured. Participants built these models under varying conditions, delimiting how freely they could divide labor during a build session. While hand movement synchrony was sensitive to the different tasks and outcomes, the heart rate measure did not show any effects of interpersonal synchrony. Results for hand movements show that the more participants were constrained by a particular building strategy, the greater their behavioral synchrony. Within the different conditions, the degree of synchrony was predictive of subjective satisfaction and objective product outcomes. However, in contrast to many previous findings, synchrony was negatively associated with superior products, and, depending on the constraints on the interaction, positively or negatively correlated with higher subjective satisfaction. These results show that the task context critically shapes the role of synchronization during joint action, and that in more complex tasks, not synchronization of behavior, but rather complementary types of behavior may be associated with superior task outcomes. PMID:27997558
Use of falling weight deflectometer multi-load data for pavement strength estimation
DOT National Transportation Integrated Search
2002-06-01
The objective of this study is to develop a mechanistic-empirical method for assessing pavement layer conditions and : estimating the remaining life of flexible pavements using multi-load level Falling Weight Deflectometer (FWD) deflections. A : dyna...
Do object refixations during scene viewing indicate rehearsal in visual working memory?
Zelinsky, Gregory J; Loschky, Lester C; Dickinson, Christopher A
2011-05-01
Do refixations serve a rehearsal function in visual working memory (VWM)? We analyzed refixations from observers freely viewing multiobject scenes. An eyetracker was used to limit the viewing of a scene to a specified number of objects fixated after the target (intervening objects), followed by a four-alternative forced choice recognition test. Results showed that the probability of target refixation increased with the number of fixated intervening objects, and these refixations produced a 16% accuracy benefit over the first five intervening-object conditions. Additionally, refixations most frequently occurred after fixations on only one to two other objects, regardless of the intervening-object condition. These behaviors could not be explained by random or minimally constrained computational models; a VWM component was required to completely describe these data. We explain these findings in terms of a monitor-refixate rehearsal system: The activations of object representations in VWM are monitored, with refixations occurring when these activations decrease suddenly.
Adapting Artworks for People Who Are Blind or Visually Impaired Using Raised Printing
ERIC Educational Resources Information Center
Krivec, Tjaša; Muck, Tadeja; Germadnik, Rolanda Fugger; Majnaric, Igor; Golob, Gorazd
2014-01-01
Everyone has the right to freely participate in the cultural life of the community (United Nations, 2012). In Europe and around the globe, many efforts have been made in order to include people with visual impairments and blindness into the cultural life. The objects and artifacts exhibited in museums for people with visual impairments are…
Fibromyalgia is Associated with Impaired Balance and Falls
Jones, Kim D.; Horak, Fay B.; Winters, Kerri Stone; Morea, Jessica M.; Bennett, Robert M.
2010-01-01
Background/Objective The purpose of this study was to determine whether FM patients differ from matched healthy controls in clinical tests of balance ability and fall frequency. Methods 34 FM patients and 32 age matched controls were administered the Balance Evaluation-Systems Test (BESTest), rated their balance confidence with the Activities-Specific Balance Confidence Scale (ABC) and reported the number of falls in the last 6 months. The Fibromyalgia Impact Questionnaire (FIQ) was used to assess FM severity. Results FM patients had significantly impaired balance in all components of the BESTest compared to controls. They also scored more poorly on balance confidence. Overall fibromyalgia severity (FIQ) correlated significantly with the BESTest, and the ABC scale. The BESTest and ABC correlated significantly with 6 commonly reported FM symptoms (excluding pain). FM patients reported a total of 37 falls over the last six-months compared to 6 falls in healthy controls. Conclusion Fibromyalgia is associated with balance problems and increased fall frequency. Patients were aware of their balance problems. These results suggest that FM may affect peripheral and/or central mechanisms of postural control. Further objective study is needed to identify the relative contributions of neural and musculoskeletal impairments to postural stability in FM, thus providing clinicians with exercise prescriptions that maximize postural stability. PMID:19125137
Lipscomb, Hester J; Dement, John M; Nolan, James; Patterson, Dennis; Li, Leiming; Cameron, Wilfred
2003-08-01
Active injury surveillance was conducted with a large, unionized workforce of residential and drywall carpenters over a 3-year period. Injured carpenters were interviewed by trained carpenter investigators and sites were visited where falls occurred. Qualitative information was collected on exposures, risk perception, training, and mentoring. Falls accounted for 20% of injuries. Same-level falls were often related to weather, carrying objects-sometimes with an obstructed view-housekeeping, terrain of the lot, and speed of work. Falls from height occurred from a variety of work surfaces and involved ladders, scaffolding, roofs, work on other unsecured surfaces, unprotected openings, speed, and weather conditions. Recognized fall protection strategies, such as guardrails, toe boards, tying off to appropriate anchors, and guarding openings, would have prevented many of these falls; these practices were not the norm on many sites.
Race and fall risk: data from the National Health and Aging Trends Study (NHATS)
Sun, Daniel Q.; Huang, Jin; Varadhan, Ravi; Agrawal, Yuri
2016-01-01
Objectives: the objective of this study was to explore whether race-based difference in fall risk may be mediated by environmental and physical performance risk factors. Methods: using data from a nationally representative longitudinal survey of 7,609 community-dwelling participants in the National Health and Aging Trends Study (NHATS), we evaluated whether racial differences in fall risk may be explained by physical performance level (measured by the Short Physical Performance Battery), mobility disability, physical activity level and likelihood of living alone. Multivariate Poisson regression and mediation models were used in analyses. Results: in whites and blacks, the annual incidence of ‘any fall’ was 33.8 and 27.1%, respectively, and the annual incidence of ‘recurrent falls’ was 15.5 and 12.3%, respectively. Compared with whites, blacks had relative risks of 0.7 (95% confidence interval 0.6–0.8) and 0.6 (0.5–0.8) for sustaining any fall and recurrent falls, respectively, in adjusted analyses. Blacks had poorer performance on the SPPB (P < 0.001), higher levels of mobility disability (P < 0.001), similar levels of physical activity (P = 0.19) and were equally likely to live alone relative to whites (P = 0.77). Mediation analysis revealed that these risk factors collectively acted as suppressors and none of these factors accounted for the racial differences in fall risk observed. Conclusions: relative to whites, blacks were at 30 and 40% decreased risk of sustaining any fall and recurrent falls, respectively. This difference in risk remains unexplained. PMID:26764401
NASA Technical Reports Server (NTRS)
Pesnell, W. Dean
2016-01-01
Dropping objects into a tunnel bored through Earth has been used to visualize simple harmonic motion for many years, and even imagined for use as rapid transport systems. Unlike previous studies that assumed a constant density Earth, here we calculate the fall-through time of polytropes, models of Earth's interior where the pressure varies as a power of the density. This means the fall-through time can be calculated as the central condensation varies from one to large within the family of polytropes. Having a family of models, rather than a single model, helps to explore the properties of planets and stars. Comparing the family of phase space solutions shows that the fall-through time and velocity approach the limit of radial free-fall onto a point mass as the central condensation increases. More condensed models give higher maximum velocities but do not have the right global properties for Earth. The angular distance one can travel along the surface is calculated as a brachistochrone (path of least time) tunnel that is a function of the depth to which the tunnel is bored. We also show that completely degenerate objects, simple models of white dwarf stars supported by completely degenerate electrons, have sizes similar to Earth but their much higher masses mean a much larger gravitational strength and a shorter fall-through time. Numerical integrations of the equations describing polytropes and completely degenerate objects are used to generate the initial models. Analytic solutions and numerical integration of the equations of motion are used to calculate the fall-through time for each model, and numerical integrations with analytic approximations at the boundaries are used to calculate the brachistochrones in the polytropes. Scaling relationships are provided to help use these results in other planets and stars.
Numerical Study of Motion of Falling Conical Graupel
NASA Astrophysics Data System (ADS)
Chueh, Chih-Che; Wang, Pao K.; Hashino, Tempei
2018-01-01
In the present study, the attitudes of freely-falling conical graupel with a realistic range of densities are investigated numerically by solving the transient Navier-Stokes equations and the body dynamics equations representing the 6-degrees-of-freedom motion. This framework allows us to determine the position and orientation of the graupel in response to the hydrodynamic force of the flow fields. The results show more significant horizontal movements than those cases with a fixed bulk density of ice assumed in our previous study. This is because the real graupel particles possess the density less than the bulk density of ice, which, in turn, leads to a relatively small mass and a relatively small set of moments of inertia. We demonstrate that, with the six degrees of freedom considered together, when Reynolds number is small, a typical damped oscillation occurs, whereas when Reynolds number is high, amplifying oscillation may occur which leads to more complicated and unpredictable flying attitudes such as tumbling. The drag coefficients obtained in the present study agree with the previous studies and can be approximated by that of spheres of the same Reynolds numbers. We also show that conical graupel can perform significant horizontal translations which can be on the order of 1 km in 1 h.
Redshift and lateshift from homogeneous and isotropic modified dispersion relations
NASA Astrophysics Data System (ADS)
Pfeifer, Christian
2018-05-01
Observables which would indicate a modified vacuum dispersion relations, possibly caused by quantum gravity effects, are a four momentum dependence of the cosmological redshift and the existence of a so called lateshift effect for massless or very light particles. Existence or non-existence of the latter is currently analyzed on the basis of the available observational data from gamma-ray bursts and compared to predictions of specific modified dispersion relation models. We consider the most general perturbation of the general relativistic dispersion relation of freely falling particles on homogeneous and isotropic spacetimes and derive the red- and lateshift to first order in the perturbation. Our result generalizes the existing formulae in the literature and we find that there exist modified dispersion relations causing both, one or none of the two effects to first order.
NASA Technical Reports Server (NTRS)
Nelson, L. S.; Blander, M.; Keil, K.; Skaggs, S. R.
1972-01-01
Chondrule-like spherules were formed from individual freely falling subcooled droplets of alumina, enstatite, forsterite, enstatite-albite and forsterite-albite mixtures that had been melted with a focused continuous CO2 laser beam. Their textures (rimmed, excentro-radial, barred, glassy) are strikingly similar to those of many meteoritic chondrules. It is suggested that the phenomena associated with rapid crystallization from the supercooled melt are responsible for the various textures observed in the artificial spherules as well as in similar meteoritic chondrules. It is suggested that the textures observed would also result from rapid crystallization of relatively slowly cooling molten droplets that may have been produced in larger scale events, including condensation from a nebula of solar composition and solidification in an ambient medium of high temperature.
Arnold, C M; Faulkner, R A; Gyurcsik, N C
2011-01-01
Older adults with decreased confidence in their ability to prevent a fall may benefit from an exercise programme that includes self-efficacy-enhancing education. The objectives of this study were to explore differences in fall-risk outcomes in older adults with higher vs. lower levels of falls efficacy and to evaluate the relationship between baseline falls-efficacy status and changes in fall risk factors following two interventions. Fifty-four older adults with hip osteoarthritis and at least one risk factor for falls received aquatic exercise twice weekly plus education once weekly (EE) or aquatic exercise only, twice weekly (EO), for 11 weeks. EE participants with low baseline falls efficacy demonstrated significantly (p<0.05) greater improvement in balance and falls efficacy compared to EE participants with high baseline falls efficacy. In the EE group only, baseline falls-efficacy status (low vs. high median split on the Activities-specific Balance Confidence Scale) was significantly (p<0.05) correlated with positive balance and falls-efficacy change scores (Spearman rank r=0.45 and 0.63 respectively). Individuals with one or more fall-risk factors and low falls efficacy may benefit from receiving an intervention that combines exercise with self-efficacy-enhancing education. Falls-efficacy screening may be important for decisions regarding referral to fall-prevention programmes.
Faulkner, R.A.; Gyurcsik, N.C.
2011-01-01
ABSTRACT Purpose: Older adults with decreased confidence in their ability to prevent a fall may benefit from an exercise programme that includes self-efficacy-enhancing education. The objectives of this study were to explore differences in fall-risk outcomes in older adults with higher vs. lower levels of falls efficacy and to evaluate the relationship between baseline falls-efficacy status and changes in fall risk factors following two interventions. Method: Fifty-four older adults with hip osteoarthritis and at least one risk factor for falls received aquatic exercise twice weekly plus education once weekly (EE) or aquatic exercise only, twice weekly (EO), for 11 weeks. Results: EE participants with low baseline falls efficacy demonstrated significantly (p<0.05) greater improvement in balance and falls efficacy compared to EE participants with high baseline falls efficacy. In the EE group only, baseline falls-efficacy status (low vs. high median split on the Activities-specific Balance Confidence Scale) was significantly (p<0.05) correlated with positive balance and falls-efficacy change scores (Spearman rank r=0.45 and 0.63 respectively). Conclusions: Individuals with one or more fall-risk factors and low falls efficacy may benefit from receiving an intervention that combines exercise with self-efficacy-enhancing education. Falls-efficacy screening may be important for decisions regarding referral to fall-prevention programmes. PMID:22942514
Heterogeneity of Falls Among Older Adults: Implications for Public Health Prevention
Kelsey, Jennifer L.; Procter-Gray, Elizabeth; Hannan, Marian T.
2012-01-01
Objectives. We examined risk factors for falls among older people according to indoor and outdoor activity at the time of the fall and explored risk factors for seriously injurious falls. Methods. Data came from MOBILIZE Boston, a prospective cohort study of 765 community-dwelling women and men, mainly aged 70 years or older. Over 4.3 years, 1737 falls were recorded, along with indoor or outdoor activity at the time of the fall. Results. Participants with poor baseline health characteristics had elevated rates of indoor falls while transitioning, walking, or not moving. Healthy, active people had elevated rates of outdoor falls during walking and vigorous activity. For instance, participants with fast, rather than normal, gait speed, had a rate ratio of 7.36 (95% confidence interval [CI] = 2.54, 21.28) for outdoor falls during vigorous activity. The likelihood of a seriously injurious fall also varied by personal characteristics, activity, and location. For example, the odds ratio for serious injury from an outdoor fall while walking outside compared to inside a participant’s neighborhood was 3.31 (95% CI = 1.33, 8.23). Conclusions. Fall prevention programs should be tailored to personal characteristics, activities, and locations. PMID:22994167
Predicting Geriatric Falls Following an Episode of Emergency Department Care: A Systematic Review
Carpenter, Christopher R.; Avidan, Michael S.; Wildes, Tanya; Stark, Susan; Fowler, Susan A.; Lo, Alexander X.
2015-01-01
Background Falls are the leading cause of traumatic mortality in geriatric adults. Despite recent multispecialty guideline recommendations that advocate for proactive fall prevention protocols in the emergency department (ED), the ability of risk factors or risk stratification instruments to identify subsets of geriatric patients at increased risk for short-term falls is largely unexplored. Objectives This was a systematic review and meta-analysis of ED-based history, physical examination, and fall risk stratification instruments with the primary objective of providing a quantitative estimate for each risk factor’s accuracy to predict future falls. A secondary objective was to quantify ED fall risk assessment test and treatment thresholds using derived estimates of sensitivity and specificity. Methods A medical librarian and two emergency physicians (EPs) conducted a medical literature search of PUBMED, EMBASE, CINAHL, CENTRAL, DARE, the Cochrane Registry, and Clinical Trials. Unpublished research was located by a hand search of emergency medicine (EM) research abstracts from national meetings. Inclusion criteria for original studies included ED-based assessment of pre-ED or post-ED fall risk in patients 65 years and older with sufficient detail to reproduce contingency tables for meta-analysis. Original study authors were contacted for additional details when necessary. The Quality Assessment Tool for Diagnostic Accuracy Studies (QUADAS-2) was used to assess individual study quality for those studies that met inclusion criteria. When more than one qualitatively similar study assessed the same risk factor for falls at the same interval following an ED evaluation, then meta-analysis was performed using Meta-DiSc software. The primary outcomes were sensitivity, specificity, and likelihood ratios for fall risk factors or risk stratification instruments. Secondary outcomes included estimates of test and treatment thresholds using the Pauker method based on accuracy, screening risk, and the projected benefits or harms of fall prevention interventions in the ED. Results A total of 608 unique and potentially relevant studies were identified, but only three met our inclusion criteria. Two studies that included 660 patients assessed 29 risk factors and two risk stratification instruments for falls in geriatric patients in the 6 months following an ED evaluation, while one study of 107 patients assessed the risk of falls in the preceding 12 months. A self-report of depression was associated with the highest positive likelihood ratio (LR) of 6.55 (95% confidence interval [CI] = 1.41 to 30.48). Six fall predictors were identified in more than one study (past falls, living alone, use of walking aid, depression, cognitive deficit, and more than six medications) and meta-analysis was performed for these risk factors. One screening instrument was sufficiently accurate to identify a subset of geriatric ED patients at low risk for falls with a negative LR of 0.11 (95% CI = 0.06 to 0.20). The test threshold was 6.6% and the treatment threshold was 27.5%. Conclusions This study demonstrates the paucity of evidence in the literature regarding ED-based screening for risk of future falls among older adults. The screening tools and individual characteristics identified in this study provide an evidentiary basis on which to develop screening protocols for geriatrics adults in the ED to reduce fall risk PMID:25293956
Factors associated with occasional and recurrent falls in Mexican community-dwelling older people.
Agudelo-Botero, Marcela; Giraldo-Rodríguez, Liliana; Murillo-González, Juana Catalina; Mino-León, Dolores; Cruz-Arenas, Esteban
2018-01-01
Falls are a frequent event among older adults that can cause wounds, disability, psychological disorders, and premature death. Although the large number of existing studies on the issue, few have been conducted in middle- and low-income countries. The objective of the present study is to identify the sociodemographic, medical, and functional performance factors associated with occasional and recurrent falls in Mexican older adults dwelling in community. Cross-sectional analysis of 9 598 adults ≥60 years old who participated in the fourth round (2015) of the Mexican Health and Aging Study. Bivariate tests were performed to evaluate the differences between covariates by distinct fall groups (no falls, occasional falls, and recurrent falls). Multiple logistic regressions with unadjusted and adjusted models were estimated. Approximately 46% of older adults had had at least one fall during the previous two years (one fall 16% and recurrent falls 30%). Occasional falls were only associated with being a woman; in addition to the sex, recurrent falls were strongly associated with advanced age, rural residence, bad and very bad self-perception of health status, activity-limiting pain, urinary incontinence, depression, arthritis, limitations in basic activities of daily living, and limitations in advanced activities of daily living. Falls, primarily recurrent falls, deserve to be addressed through multifactorial strategies that include different areas of intervention.
Falls risk among a very old home-dwelling population
Iinattiniemi, Sari; Jokelainen, Jari; Luukinen, Heikki
2009-01-01
Objective The aim of this prospective study was to examine risk factors of falling in a very old home-dwelling population. Design A prospective study of home-dwelling elderly people. Methods Baseline data were collected by home-nursing staff through postal questionnaires and clinical tests. Data on falls were recorded in telephone interviews every other month during a follow-up of 11 months constituting 494 person years (PY). Negative binomial modeling was used to assess fall risk. Setting General community. Subjects A population sample of home-dwelling subjects aged 85 years or older (n = 555). Main outcome measures Fall rate and risk factors of falls. Results Altogether 512 falls occurred in 273 (49%) subjects, incidence rate 1.03/PY. According to a multivariate model, history of recurrent falling, trouble with vision when moving, use of antipsychotic drug, and feelings of anxiety, nervousness, or fear were independent risk factors for subsequent falls. Conclusion Appropriate care of poor vision and feelings of anxiety, nervousness, or fear, and avoidance of use of antipsychotic drugs might be useful in the prevention of falls among the most elderly home-dwellers. PMID:19065453
Electromagnetic Radiation Reaction in General Relativity.
NASA Astrophysics Data System (ADS)
O'Donnell, Nuala
Available from UMI in association with The British Library. This thesis examines the electromagnetic radiation reaction felt by a charged body falling freely in an external gravitational field in general relativity. The original objective was to find a new derivation of the radiation reaction force F^{i} of DeWitt and DeWitt^1 which was calculated for the special case of a point charge falling in slow motion in a weak, static gravitational field: F ^{i} = {2over 3}e^2R^{i}_{0j0 }v^{j}. This may be thought of as a local expression since it involves the particle's velocity v^{j } and the local Riemann curvature tensor R ^{i}_{0j0}. Its derivation involves integrals over the whole history of the particle, covering distances of approximately the length scale on which R^{i}_{0j0 } changes. This is different from calculations of the Abraham-Lorentz force of flat space-time involving integrals over distances only a few times the size of the charge. This work was motivated by the wish to find a "local" derivation of the local reaction force. Using Schutz's^2 local initial value method to solve the problem of a charged, rigid, spherically symmetric body moving in an external gravitational field of arbitrary metric. Calculations are done in a Riemann normal coordinate system ^3 and are only valid in a normal neighbourhood of the origin, where geodesics have not begun to cross one another. We solve Maxwell's equations for the self -force by making a slow-motion approximation and keeping terms to first order only in the Riemann tensor and velocity. It is surprising that we find no local radiation reaction. Consider two particles in a static spacetime with the same initial conditions at t = 0. Particle A is that of DeWitt and DeWitt; it feels a reaction force F^{i} = {2over 3}e^2R^{i }_{0j0}v^{j}. Particle B is accelerated from rest to the same small velocity; it feels no reaction force. The two particles therefore follow different trajectories. We conclude that there is a certain amount of history dependence in curved spacetime which is absent in flat spacetime where the Abraham-Lorentz reaction force acts equally on both particles. ftn ^1C. M. DeWitt and B. S. Brehme, Falling Charges, Phys., 1, 3 (1964). ^2B. F. Schutz, Statistical Formulation of Gravitational Radiation Reaction, Phys. Rev. D., 22, 249 (1980). ^3See for example A. Z. Petrov, Einstein Spaces, p.33, Pergamon Press (1969).
Optical cuff for optogenetic control of the peripheral nervous system
NASA Astrophysics Data System (ADS)
Michoud, Frédéric; Sottas, Loïc; Browne, Liam E.; Asboth, Léonie; Latremoliere, Alban; Sakuma, Miyuki; Courtine, Grégoire; Woolf, Clifford J.; Lacour, Stéphanie P.
2018-02-01
Objective. Nerves in the peripheral nervous system (PNS) contain axons with specific motor, somatosensory and autonomic functions. Optogenetics offers an efficient approach to selectively activate axons within the nerve. However, the heterogeneous nature of nerves and their tortuous route through the body create a challenging environment to reliably implant a light delivery interface. Approach. Here, we propose an optical peripheral nerve interface—an optocuff—, so that optogenetic modulation of peripheral nerves become possible in freely behaving mice. Main results. Using this optocuff, we demonstrate orderly recruitment of motor units with epineural optical stimulation of genetically targeted sciatic nerve axons, both in anaesthetized and in awake, freely behaving animals. Behavioural experiments and histology show the optocuff does not damage the nerve thus is suitable for long-term experiments. Significance. These results suggest that the soft optocuff might be a straightforward and efficient tool to support more extensive study of the PNS using optogenetics.
Gulati, Srishti; Cao, Vania Y.; Otte, Stephani
2017-01-01
In vivo circuit and cellular level functional imaging is a critical tool for understanding the brain in action. High resolution imaging of mouse cortical neurons with two-photon microscopy has provided unique insights into cortical structure, function and plasticity. However, these studies are limited to head fixed animals, greatly reducing the behavioral complexity available for study. In this paper, we describe a procedure for performing chronic fluorescence microscopy with cellular-resolution across multiple cortical layers in freely behaving mice. We used an integrated miniaturized fluorescence microscope paired with an implanted prism probe to simultaneously visualize and record the calcium dynamics of hundreds of neurons across multiple layers of the somatosensory cortex as the mouse engaged in a novel object exploration task, over several days. This technique can be adapted to other brain regions in different animal species for other behavioral paradigms. PMID:28654056
Normal probability plots with confidence.
Chantarangsi, Wanpen; Liu, Wei; Bretz, Frank; Kiatsupaibul, Seksan; Hayter, Anthony J; Wan, Fang
2015-01-01
Normal probability plots are widely used as a statistical tool for assessing whether an observed simple random sample is drawn from a normally distributed population. The users, however, have to judge subjectively, if no objective rule is provided, whether the plotted points fall close to a straight line. In this paper, we focus on how a normal probability plot can be augmented by intervals for all the points so that, if the population distribution is normal, then all the points should fall into the corresponding intervals simultaneously with probability 1-α. These simultaneous 1-α probability intervals provide therefore an objective mean to judge whether the plotted points fall close to the straight line: the plotted points fall close to the straight line if and only if all the points fall into the corresponding intervals. The powers of several normal probability plot based (graphical) tests and the most popular nongraphical Anderson-Darling and Shapiro-Wilk tests are compared by simulation. Based on this comparison, recommendations are given in Section 3 on which graphical tests should be used in what circumstances. An example is provided to illustrate the methods. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
OpenCFU, a New Free and Open-Source Software to Count Cell Colonies and Other Circular Objects
Geissmann, Quentin
2013-01-01
Counting circular objects such as cell colonies is an important source of information for biologists. Although this task is often time-consuming and subjective, it is still predominantly performed manually. The aim of the present work is to provide a new tool to enumerate circular objects from digital pictures and video streams. Here, I demonstrate that the created program, OpenCFU, is very robust, accurate and fast. In addition, it provides control over the processing parameters and is implemented in an intuitive and modern interface. OpenCFU is a cross-platform and open-source software freely available at http://opencfu.sourceforge.net. PMID:23457446
Fall prevention and vitamin D in the elderly: an overview of the key role of the non-bone effects
2010-01-01
Preventing falls and fall-related fractures in the elderly is an objective yet to be reached. There is increasing evidence that a supplementation of vitamin D and/or of calcium may reduce the fall and fracture rates. A vitamin D-calcium supplement appears to have a high potential due to its simple application and its low cost. However, published studies have shown conflicting results as some studies failed to show any effect, while others reported a significant decrease of falls and fractures. Through a 15-year literature overview, and after a brief reminder on mechanism of falls in older adults, we reported evidences for a vitamin D action on postural adaptations - i.e., muscles and central nervous system - which may explain the decreased fall and bone fracture rates and we underlined the reasons for differences and controversies between published data. Vitamin D supplementation should thus be integrated into primary and secondary fall prevention strategies in older adults. PMID:20937091
Shorr, Ronald I.; Mion, Lorraine C.; Chandler, A. Michelle; Rosenblatt, Linda C.; Lynch, Debra; Kessler, Lori A.
2008-01-01
OBJECTIVES To determine the utility of a fall evaluation service to improve the ascertainment of falls in acute care. DESIGN Six-month observational study. SETTING Sixteen adult nursing units (349 beds) in an urban, academically affiliated, community hospital. PARTICIPANTS Patients admitted to the study units during the study period. INTERVENTION Nursing staff identifying falls were instructed to notify, using a pager, a trained nurse ‘‘fall evaluator.’’ Fall evaluators provided 24-hour-per-day 7-day-per-week coverage throughout the study. Data on patient falls gathered by fall evaluators were compared with falls data obtained through the hospital’s incident reporting system. RESULTS During 51,180 patient-days of observation, 191 falls were identified according to incident reports (3.73 falls/1,000 patient-days), whereas the evaluation service identified 228 falls (4.45 falls/1,000 patient-days). Combining falls reported from both data sources yielded 266 falls (5.20 falls/1,000 patient-days), a 39% relative rate increase compared with incident reports alone (P<.001). For falls with injury, combining data from both sources yielded 79 falls (1.54 injurious falls/1,000 patient-days), compared with 57 falls (1.11 injurious falls/1,000 patient-days) filed in incident reports—a 28% increase (P = .06). In the 16 nursing units, the relative percentage increase of captured fall events using the combined data sources versus the incident reporting system alone ranged from 13% to 125%. CONCLUSION Incident reports significantly underestimate both injurious and noninjurious falls in acute care settings and should not be used as the sole source of data for research or quality improvement initiatives. PMID:18205761
Preoperative Falls Predict Postoperative Falls, Functional Decline, and Surgical Complications.
Kronzer, Vanessa L; Jerry, Michelle R; Ben Abdallah, Arbi; Wildes, Troy S; Stark, Susan L; McKinnon, Sherry L; Helsten, Daniel L; Sharma, Anshuman; Avidan, Michael S
2016-10-01
Falls are common and linked to morbidity. Our objectives were to characterize postoperative falls, and determine whether preoperative falls independently predicted postoperative falls (primary outcome), functional dependence, quality of life, complications, and readmission. This prospective cohort study included 7982 unselected patients undergoing elective surgery. Data were collected from the medical record, a baseline survey, and follow-up surveys approximately 30days and one year after surgery. Fall rates (per 100 person-years) peaked at 175 (hospitalization), declined to 140 (30-day survey), and then to 97 (one-year survey). After controlling for confounders, a history of one, two, and ≥three preoperative falls predicted postoperative falls at 30days (adjusted odds ratios [aOR] 2.3, 3.6, 5.5) and one year (aOR 2.3, 3.4, 6.9). One, two, and ≥three falls predicted functional decline at 30days (aOR 1.2, 2.4, 2.4) and one year (aOR 1.3, 1.5, 3.2), along with in-hospital complications (aOR 1.2, 1.3, 2.0). Fall history predicted adverse outcomes better than commonly-used metrics, but did not predict quality of life deterioration or readmission. Falls are common after surgery, and preoperative falls herald postoperative falls and other adverse outcomes. A history of preoperative falls should be routinely ascertained. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.
Speiser, Daniel I; Gagnon, Yakir Luc; Chhetri, Raghav K; Oldenburg, Amy L; Johnsen, Sönke
2016-11-01
The eyes of scallops form images using a concave spherical mirror and contain two separate retinas, one layered on top of the other. Behavioral and electrophysiological studies indicate that the images formed by these eyes have angular resolutions of about 2°. Based on previous ray-tracing models, it has been thought that the more distal of the two retinas lies near the focal point of the mirror and that the proximal retina, positioned closer to the mirror at the back of the eye, receives light that is out-of-focus. Here, we propose three mechanisms through which both retinas may receive focused light: (1) chromatic aberration produced by the lens may cause the focal points for longer and shorter wavelengths to fall near the distal and proximal retinas, respectively; (2) focused light from near and far objects may fall on the distal and proximal retinas, respectively; and (3) the eyes of scallops may be dynamic structures that change shape to determine which retina receives focused light. To test our hypotheses, we used optical coherence tomography (OCT), a method of near-infrared optical depth-ranging, to acquire virtual cross-sections of live, intact eyes from the bay scallop Argopecten irradians Next, we used a custom-built ray-tracing model to estimate the qualities of the images that fall on an eye's distal and proximal retinas as functions of the wavelengths of light entering the eye (400-700 nm), object distances (0.01-1 m), and the overall shape of the eye. When we assume 550 nm wavelength light and object distances greater than 0.01 m, our model predicts that the angular resolutions of the distal and proximal retinas are 2° and 7°, respectively. Our model also predicts that neither chromatic aberration nor differences in object distance lead to focused light falling on the distal and proximal retinas simultaneously. However, if scallops can manipulate the shapes of their eyes, perhaps through muscle contractions, we speculate that they may be able to influence the qualities of the images that fall on their proximal retinas and-to a lesser extent-those that fall on their distal retinas as well. © The Author 2016. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology.
Speiser, Daniel I.; Gagnon, Yakir Luc; Chhetri, Raghav K.; Oldenburg, Amy L.; Johnsen, Sönke
2016-01-01
The eyes of scallops form images using a concave spherical mirror and contain two separate retinas, one layered on top of the other. Behavioral and electrophysiological studies indicate that the images formed by these eyes have angular resolutions of about 2°. Based on previous ray-tracing models, it has been thought that the more distal of the two retinas lies near the focal point of the mirror and that the proximal retina, positioned closer to the mirror at the back of the eye, receives light that is out-of-focus. Here, we propose three mechanisms through which both retinas may receive focused light: (1) chromatic aberration produced by the lens may cause the focal points for longer and shorter wavelengths to fall near the distal and proximal retinas, respectively; (2) focused light from near and far objects may fall on the distal and proximal retinas, respectively; and (3) the eyes of scallops may be dynamic structures that change shape to determine which retina receives focused light. To test our hypotheses, we used optical coherence tomography (OCT), a method of near-infrared optical depth-ranging, to acquire virtual cross-sections of live, intact eyes from the bay scallop Argopecten irradians. Next, we used a custom-built ray-tracing model to estimate the qualities of the images that fall on an eye’s distal and proximal retinas as functions of the wavelengths of light entering the eye (400–700 nm), object distances (0.01–1 m), and the overall shape of the eye. When we assume 550 nm wavelength light and object distances greater than 0.01 m, our model predicts that the angular resolutions of the distal and proximal retinas are 2° and 7°, respectively. Our model also predicts that neither chromatic aberration nor differences in object distance lead to focused light falling on the distal and proximal retinas simultaneously. However, if scallops can manipulate the shapes of their eyes, perhaps through muscle contractions, we speculate that they may be able to influence the qualities of the images that fall on their proximal retinas and—to a lesser extent—those that fall on their distal retinas as well. PMID:27549200
Haasum, Ylva; Fastbom, Johan; Johnell, Kristina
2016-01-01
Objectives Many drugs increase the risk of falls in old age. Although persons with Parkinson’s disease (PD) are at increased risk of experiencing falls and fractures, the use of fall-risk inducing drugs (FRIDs) in this population has not previously been investigated. The objective of this study was to investigate the burden of use of FRIDs in older persons treated with anti-Parkinson drugs (APD; used as a proxy for PD), compared to persons without APD. Methods We analyzed individual data on age, sex, type of housing and drug use in 1 346 709 persons aged ≥ 65 years in the Swedish Prescribed Drug Register on the date of 30 September 2008. Main outcome measure was the use of FRIDs. Results FRIDs were used by 79% of persons with APD and 75% of persons without APD. Persons with APD were more likely to use ≥ 1 FRIDs compared to persons without APD (adjusted OR: 1.09; 95% CI: 1.06-1-12). The association was stronger for concomitant use of ≥ 5 FRIDS (adjusted OR: 1.49; 95% CI: 1.44–1.55). Conclusions The high use of FRIDs among persons with APD indicates that these patients may be at increased risk of drug-induced falls. Further studies are needed to investigate how these drugs affect the risk of falling in persons with PD. PMID:27537366
Project Photofly: New 3d Modeling Online Web Service (case Studies and Assessments)
NASA Astrophysics Data System (ADS)
Abate, D.; Furini, G.; Migliori, S.; Pierattini, S.
2011-09-01
During summer 2010, Autodesk has released a still ongoing project called Project Photofly, freely downloadable from AutodeskLab web site until August 1 2011. Project Photofly based on computer-vision and photogrammetric principles, exploiting the power of cloud computing, is a web service able to convert collections of photographs into 3D models. Aim of our research was to evaluate the Project Photofly, through different case studies, for 3D modeling of cultural heritage monuments and objects, mostly to identify for which goals and objects it is suitable. The automatic approach will be mainly analyzed.
Furness, Trentham; Mnatzaganian, George; Garlick, Robyn; Ireland, Susan; McKenna, Brian; Hill, Keith D
2017-12-01
Despite the high risk of falling for people with severe mental illness, there is limited falls research in mental health settings. Therefore, the objective of this observational cohort study was to conduct a focused post-fall review of fall episodes within aged acute inpatient mental health units at one of Australia's largest publicly funded mental health organizations. A post-fall reporting tool was developed to collect intrinsic and extrinsic fall risk factors among three aged acute mental health inpatient units over an 18-month period. Descriptive and inferential analyses were conducted to describe fall risk factors and predictors of fall risk. There were a total of 115 falls, of which the tool was used for 93 (80.9%) episodes. Falls occurred most often in consumer's bedroom/bathroom and were unwitnessed. Intrinsic risk factors were most often attributed to postural drop and losing balance during walking. However, that was in contrast to consumer's who self-reported feeling dizzy as the reason of the fall. Based on the cohort, future falls could be reduced by targeting those aged above 82 years, or with a diagnosis of dementia. Recurrent falls during admission could be reduced by targeting those with psychotic illness and males with a diagnosis of dementia. A clearer dialogue among consumers and clinical staff reporting about fall episodes may support future remedial interventions and inform programs to reduce fall risk and assist the challenge of describing unwitnessed falls in aged acute inpatient mental health settings.
Fall Risk is Not Black and White
Kiely, Dan K.; Kim, Dae Hyun; Gross, Alden L.; Habtemariam, Daniel A.; Leveille, Suzanne G.; Li, Wenjun; Lipsitz, Lewis A.
2015-01-01
Objective To determine whether previously reported racial differences in fall rates between White and Black/African American is explained by differences in health status and neighborhood characteristics. Design Prospective cohort Setting Community Participants The study included 550 White and 116 Black older adults in the Greater Boston area (mean age: 78 years; 36% men) who were English-speaking, able to walk across a room, and without severe cognitive impairment. Measurements Falls were prospectively reported using monthly fall calendars. The location of each fall and fall-related injuries were asked during telephone interviews. At baseline, we assessed risk factors for falls, including sociodemographic characteristics, physiologic risk factors, physical activity, and community-level characteristics. Results Over the mean follow-up of 1,048 days, 1,539 falls occurred (incidence: 806/1,000 person-years). Whites were more likely than Blacks to experience any falls (867 versus 504 falls per 1,000 person-years; RR [95% CI]: 1.77 [1.33, 2.36]), outdoor falls (418 versus 178 falls per 1,000 person-years; 1.78 [1.08, 2.92]), indoor falls (434 versus 320 falls per 1,000 person-years; 1.44 [1.02, 2.05]), and injurious falls (367 versus 205 falls per 1,000 person-years; 1.79 [1.30, 2.46]). With exception of injurious falls, higher fall rates in Whites than Blacks were substantially attenuated with adjustment for risk factors and community-level characteristics: any fall (1.24 [0.81, 1.89]), outdoor fall (1.57 [0.86, 2.88]), indoor fall (1.08 [0.64, 1.81]), and injurious fall (1.77 [1.14, 2.74]). Conclusion Our findings suggest that the racial differences in fall rates may be largely due to confounding by individual-level and community-level characteristics. PMID:26855845
Hunger promotes acquisition of nonfood objects.
Xu, Alison Jing; Schwarz, Norbert; Wyer, Robert S
2015-03-03
Hunger motivates people to consume food, for which finding and acquiring food is a prerequisite. We test whether the acquisition component spills over to nonfood objects: Are hungry people more likely to acquire objects that cannot satisfy their hunger? Five laboratory and field studies show that hunger increases the accessibility of acquisition-related concepts and the intention to acquire not only food but also nonfood objects. Moreover, people act on this intention and acquire more nonfood objects (e.g., binder clips) when they are hungry, both when these items are freely available and when they must be paid for. However, hunger does not influence how much they like nonfood objects. We conclude that a basic biologically based motivation can affect substantively unrelated behaviors that cannot satisfy the motivation. This presumably occurs because hunger renders acquisition-related concepts and behaviors more accessible, which influences decisions in situations to which they can be applied.
Hunger promotes acquisition of nonfood objects
Xu, Alison Jing; Schwarz, Norbert; Wyer, Robert S.
2015-01-01
Hunger motivates people to consume food, for which finding and acquiring food is a prerequisite. We test whether the acquisition component spills over to nonfood objects: Are hungry people more likely to acquire objects that cannot satisfy their hunger? Five laboratory and field studies show that hunger increases the accessibility of acquisition-related concepts and the intention to acquire not only food but also nonfood objects. Moreover, people act on this intention and acquire more nonfood objects (e.g., binder clips) when they are hungry, both when these items are freely available and when they must be paid for. However, hunger does not influence how much they like nonfood objects. We conclude that a basic biologically based motivation can affect substantively unrelated behaviors that cannot satisfy the motivation. This presumably occurs because hunger renders acquisition-related concepts and behaviors more accessible, which influences decisions in situations to which they can be applied. PMID:25730858
Rasche, Peter; Mertens, Alexander; Brandl, Christopher; Liu, Shan; Buecking, Benjamin; Bliemel, Christopher; Horst, Klemens; Weber, Christian David; Lichte, Philipp; Knobe, Matthias
2018-03-27
Prohibiting falls and fall-related injuries is a major challenge for health care systems worldwide, as a substantial proportion of falls occur in older adults who are previously known to be either frail or at high risk for falls. Hence, preventive measures are needed to educate and minimize the risk for falls rather than just minimize older adults' fall risk. Health apps have the potential to address this problem, as they enable users to self-assess their individual fall risk. The objective of this study was to identify product features of a fall prevention smartphone app, which increase or decrease users' satisfaction. In addition, willingness to pay (WTP) was assessed to explore how much revenue such an app could generate. A total of 96 participants completed an open self-selected Web-based survey. Participants answered various questions regarding health status, subjective and objective fall risk, and technical readiness. Seventeen predefined product features of a fall prevention smartphone app were evaluated twice: first, according to a functional (product feature is implemented in the app), and subsequently by a dysfunctional (product feature is not implemented in the app) question. On the basis of the combination of answers from these 2 questions, the product feature was assigned to a certain category (must-be, attractive, one-dimensional, indifferent, or questionable product feature). This method is widely used in user-oriented product development and captures users' expectations of a product and how their satisfaction is influenced by the availability of individual product features. Five product features were identified to increase users' acceptance, including (1) a checklist of typical tripping hazards, (2) an emergency guideline in case of a fall, (3) description of exercises and integrated workout plans that decrease the risk of falling, (4) inclusion of a continuous workout program, and (5) cost coverage by health insurer. Participants' WTP was assessed after all 17 product features were rated and revealed a median monthly payment WTP rate of €5.00 (interquartile range 10.00). The results show various motivating product features that should be incorporated into a fall prevention smartphone app. Results reveal aspects that fall prevention and intervention designers should keep in mind to encourage individuals to start joining their program and facilitate long-term user engagement, resulting in a greater interest in fall risk prevention. ©Peter Rasche, Alexander Mertens, Christopher Brandl, Shan Liu, Benjamin Buecking, Christopher Bliemel, Klemens Horst, Christian David Weber, Philipp Lichte, Matthias Knobe. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 27.03.2018.
Illicit Use of Prescription ADHD Medications on a College Campus: A Multimethodological Approach
ERIC Educational Resources Information Center
DeSantis, Alan D.; Webb, Elizabeth M.; Noar, Seth M.
2008-01-01
Objective: The authors used quantitative and qualitative methodologies to investigate college students' perceptions and use of illegal Attention Deficit Hyperactivity Disorder (ADHD) stimulants during spring and summer 2006. Participants: From fall 2005 through fall 2006, the authors studied 1,811 undergraduates at a large, public, southeastern…
Schepens, Stacey L.; Panzer, Victoria; Goldberg, Allon
2012-01-01
OBJECTIVE We attempted to determine whether multimedia fall prevention education using different instructional strategies increases older adults’ knowledge of fall threats and their fall prevention behaviors. METHOD Fifty-three community-dwelling older adults were randomized to two educational groups or a control group. Multimedia-based educational interventions to increase fall threats knowledge and encourage fall prevention behaviors had two tailoring strategies: (1) improve content realism for individual learners (authenticity group) and (2) highlight program goals and benefits while using participants’ content selections (motivation group). Knowledge was measured at baseline and 1-mo follow-up. Participants recorded prevention behaviors for 1 mo. RESULTS Intervention group participants showed greater knowledge gains and posttest knowledge than did control group participants. The motivation group engaged in more prevention behaviors over 1 mo than did the other groups. CONCLUSION Tailoring fall prevention education by addressing authenticity and motivation successfully improved fall threats knowledge. Combining motivational strategies with multimedia education increased the effectiveness of the intervention in encouraging fall prevention behaviors. PMID:22214115
Why Do Patients in Acute Care Hospitals Fall? Can Falls Be Prevented?
Dykes, Patricia C.; Carroll, Diane L.; Hurley, Ann C.; Benoit, Angela; Middleton, Blackford
2011-01-01
Objective Obtain the views of nurses and assistants as to why patients in acute care hospitals fall. Background Despite a large quantitative evidence base for guiding fall risk assessment and not needing highly technical, scarce, or expensive equipment to prevent falls, falls are serious problems in hospitals. Methods Basic content analysis methods were used to interpret descriptive data from 4 focus groups with nurses (n = 23) and 4 with assistants (n = 19). A 2-person consensus approach was used for analysis. Results Positive and negative components of 6 concepts—patient report, information access, signage, environment, teamwork, and involving patient/family—formed 2 core categories: knowledge/communication and capability/actions that are facilitators or barriers, respectively, to preventing falls. Conclusion Two conditions are required to reduce patient falls. A patient care plan including current and accurate fall risk status with associated tailored and feasible interventions needs to be easily and immediately accessible to all stakeholders (entire healthcare team, patients, and family). Second, stakeholders must use that information plus their own knowledge and skills and patient and hospital resources to carry out the plan. PMID:19509605
Somatosensory attunement to the rigid body laws.
Shockley, K; Grocki, M; Carello, C; Turvey, M T
2001-01-01
In the most general case, haptic perception of an object's heaviness is most likely the perception of the object's resistance to movement, determined jointly by the object's mass and mass distribution. In two experiments with occluded objects wielded freely in three dimensions, we showed additive effects on perceived heaviness of mass and the inertia tensor. Our manipulations of the inertia tensor were directed specifically at the volume and symmetry of the inertia ellipsoid, quantities that can be understood as important to controlling the level and patterning of muscular forces, respectively. Ellipsoid volume and symmetry were found to have separate effects on perceptual reports of heaviness that were invariant over different tensors. Independent sensitivities to translational inertia and particular characterizations of rotational inertia suggest specialized somatosensory attunement to the rigid body laws.
Factors associated with occasional and recurrent falls in Mexican community-dwelling older people
Mino-León, Dolores; Cruz-Arenas, Esteban
2018-01-01
Falls are a frequent event among older adults that can cause wounds, disability, psychological disorders, and premature death. Although the large number of existing studies on the issue, few have been conducted in middle- and low-income countries. The objective of the present study is to identify the sociodemographic, medical, and functional performance factors associated with occasional and recurrent falls in Mexican older adults dwelling in community. Cross-sectional analysis of 9 598 adults ≥60 years old who participated in the fourth round (2015) of the Mexican Health and Aging Study. Bivariate tests were performed to evaluate the differences between covariates by distinct fall groups (no falls, occasional falls, and recurrent falls). Multiple logistic regressions with unadjusted and adjusted models were estimated. Approximately 46% of older adults had had at least one fall during the previous two years (one fall 16% and recurrent falls 30%). Occasional falls were only associated with being a woman; in addition to the sex, recurrent falls were strongly associated with advanced age, rural residence, bad and very bad self-perception of health status, activity-limiting pain, urinary incontinence, depression, arthritis, limitations in basic activities of daily living, and limitations in advanced activities of daily living. Falls, primarily recurrent falls, deserve to be addressed through multifactorial strategies that include different areas of intervention. PMID:29462159
Petitpierre, Nicolas Julien; Trombetti, Andrea; Carroll, Iain; Michel, Jean-Pierre; Herrmann, François Richard
2010-05-01
the main objective was to evaluate if the admission functional independence measure (FIM) score could be used to predict the risk of falls in geriatric inpatients. a 10-year retrospective study was performed. the study was conducted in a 298-bed geriatric teaching hospital in Geneva, Switzerland. all patients discharged from the hospital from 1 January 1997 to 31 December 2006 were selected. measures used were FIM scores at admission using the FIM instrument and number of falls extracted from the institution's fall report forms. during the study period, there were 23,966 hospital stays. A total of 8,254 falls occurred. Of these, 7,995 falls were linked to 4,651 stays. Falls were recorded in 19.4% of hospital stays, with a mean incidence of 7.84 falls per 1,000 patients-days. Although there was a statistically significant relationship between total FIM score, its subscales, and the risk of falling, the sensitivity, specificity, positive predictive value and negative predictive value obtained with receiver operating characteristic curves were insufficient to permit fall prediction. This might be due in part to a non-linear relationship between FIM score and fall risk. in this study, the FIM instrument was found to be unable to predict risk of falls in general geriatric wards.
Taylor-Piliae, Ruth E; Mohler, M Jane; Najafi, Bijan; Coull, Bruce M
2016-12-01
Stroke survivors often have persistent neural deficits related to motor function and sensation, which increase their risk of falling, most of which occurs at home or in community settings. The use of wearable technology to monitor fall risk and gait in stroke survivors may prove useful in enhancing recovery and/or preventing injuries. Determine the feasibility of using wearable technology (PAMSys™) to objectively monitor fall risk and gait in home and community settings in stroke survivors. In this feasibility study, we used the PAMSys to identify fall risk indicators (postural transitions: duration in seconds, and number of unsuccessful attempts), and gait (steps, speed, duration) for 48 hours during usual daily activities in stroke survivors (n = 10) compared to age-matched controls (n = 10). A questionnaire assessed device acceptability. Stroke survivors mean age was 70 ± 8 years old, were mainly Caucasian (60%) women (70%), and not significantly different than the age-matched controls (all P-values >0.20). Stroke survivors (100%) reported that the device was comfortable to wear, didn't interfere with everyday activities, and were willing to wear it for another 48 hours. None reported any difficulty with the device while sleeping, removing/putting back on for showering or changing clothes. When compared to controls, stroke survivors had significantly worse fall risk indicators and walked less (P < 0.05). Stroke survivors reported high acceptability of 48 hours of continuous PAMSys monitoring. The use of in-home wearable technology may prove useful in monitoring fall risk and gait in stroke survivors, potentially enhancing recovery.
Outcomes of a Falls Prevention Education Program Among Older Adults in Grenada.
Lyons, Beverly P; Hall, Raphael J
2016-10-01
In Latin America and the Caribbean, there is a scarcity of data on falls, the leading cause of death as a result of unintentional injuries, among older adults aged 65+ years of age. By 2050, 80 % of the 2 billion older adults worldwide are expected to be living in this region; therefore, it is imperative that this issue receive urgent attention from community health practitioners, health educators and policy makers. Guided by Pillar 1-awareness of the WHO fall prevention model for community-dwelling older adults, the purpose of this paper was to describe the feasibility of implementing a falls prevention awareness educational initiative in the Eastern Caribbean Island of Grenada. Sixty-two older adults, average age 67, participated in a falls awareness workshop. An anonymous pre-workshop falls assessment checklist was distributed to establish baseline information followed by an interactive workshop. Eight fall risks were identified and 52 % of the participants reported a history of falls. Based on the group's eagerness to participate, we are encouraged that falls prevention intervention initiatives are feasible among others of similar characteristics in Grenada and plan to implement Pillar II-objective falls assessment and Pillar III-on-going interventions.
Research notes : detecting objects at railroad crossings.
DOT National Transportation Integrated Search
2004-04-01
The highest risks are at intersections with roadways. An object may fall off of a truck or farm vehicle, or someone may drop something. The goal of this research was to evaluate promising technologies for the detection of such objects at railroad-roa...
The fluid dynamics of the chocolate fountain
NASA Astrophysics Data System (ADS)
Townsend, Adam K.; Wilson, Helen J.
2016-01-01
We consider the fluid dynamics of the chocolate fountain. Molten chocolate is a mildly shear-thinning non-Newtonian fluid. Dividing the flow into three main domains—the pumped flow up the centre, the film flow over each dome, and the freely falling curtain flow between the domes—we generate a wide-ranging study of Newtonian and non-Newtonian fluid mechanics. The central pumped flow is a benchmark to elucidate the effects of shear-thinning. The dome flow can be modelled as a thin-film flow with the leading-order effects being a simple balance of gravity and viscosity. Finally, the curtain flow is analytically intractable but is related to the existing theory of water bells (both inviscid and viscous). In pipe flow, Newtonian fluids exhibit a parabolic velocity profile; shear-thinning makes the profile more blunted. In thin-film flow over the dome, gravitational and viscous effects balance and the dome shape is not important beyond the local slope. We find that the chocolate thins and slows down as it travels down the dome. Finally, in the curtain flow, we predict the shape of the falling sheet for an inviscid fluid, and compare this with the literature to predict the shape for a viscous fluid, having shown that viscous forces are too great to ignore. We also find that the primary effect driving the shape of the curtain (which falls inwards towards the axis of the fountain) is surface tension. We find that the three domains provide excellent introductions to non-Newtonian mechanics, the important mathematical technique of scaling, and how to manipulate existing data to make our own predictions. We also find that the topic generates interest among the public in our engagement work.
Performance of Compiler-Assisted Memory Safety Checking
2014-08-01
software developer has in mind a particular object to which the pointer should point, the intended referent. A memory access error occurs when an ac...Performance of Compiler-Assisted Memory Safety Checking David Keaton Robert C. Seacord August 2014 TECHNICAL NOTE CMU/SEI-2014-TN...based memory safety checking tool and the performance that can be achieved with two such tools whose source code is freely available. The note then
Paul, Serene S; Harvey, Lara; Carroll, Therese; Li, Qiang; Boufous, Soufiane; Priddis, Annabel; Tiedemann, Anne; Clemson, Lindy; Lord, Stephen R; Muecke, Sandy; Close, Jacqueline Ct; Lo, Serigne; Sherrington, Catherine
2017-10-11
Objective and importance of study: To describe characteristics and temporal trends of fall-related ambulance service use and hospital admission in older adults in New South Wales (NSW), Australia. Such information will facilitate a more targeted approach to planning and delivery of health services to prevent falls and their adverse sequelae in different groups of older adults. Retrospective population-based descriptive study. Fall-related ambulance use and hospital admissions for all falls and injurious falls in NSW residents aged ≥65 years between 2006 and 2013 were obtained from two discrete sources of routinely collected data. Rates of use are presented descriptively. There were 314 041 occasions of fall-related ambulance use by older adults and 331 311 fall-related hospitalisations, of which 69% (n = 227 753) were for injurious falls. Fractures accounted for 57% of injurious hospitalisations. Slips and trips were the most common mechanism of falls requiring hospitalisation (52%). Residents of aged care facilities had a greater proportion of fall injury hospitalisations compared with people living in the community (85% and 65%, respectively). Rates of fall-related ambulance use and hospitalisation were similar and continued to increase over time. Increased effort is needed to prevent falls and associated injury among older people in NSW, particularly among people living in aged care facilities. Ongoing monitoring of rates and the characteristics of people who fall are needed to determine the long-term impact of fall prevention interventions.
New geometric and field theoretic aspects of a radiation dominated universe
NASA Astrophysics Data System (ADS)
Modak, Sujoy K.
2018-05-01
The homogeneous and isotropic radiation dominated universe, following the inflationary stage, is expressed as a spherically symmetric and inhomogeneous spacetime upon a power-law-type conformal transformation of the null (cosmological) coordinates. This new spacetime metric has many interesting properties. While the static observers, at a fixed position in this new spacetime, do not see any horizon, some nonstatic observers encounter a horizon due to their motion which is analogous to the situation of Rindler observers in Minkowski spacetime. The symmetry of the new metric offers a unitarily inequivalent quantization of the massless scalar field and provides a new example of particle creation. We calculate the particle content of the cosmological vacuum state with respect to the static observer in this new spacetime who, with respect to cosmological time, is freely falling in the asymptotic past and future but accelerated in between.
Is the Kerr black hole a super accelerator?
NASA Astrophysics Data System (ADS)
Krasnikov, S.; Skvortsova, M. V.
2018-02-01
A number of long-standing puzzles, such as the origin of extreme-energy cosmic rays, could perhaps be solved if we found a mechanism for effectively transferring energy from black holes to particles and, correspondingly, accelerating the latter to (unboundedly, as long as we neglect the back reaction) large velocities. As of today the only such candidate mechanism in the case of the nonextreme Kerr black hole is colliding a particle that freely falls from infinity with a particle whose trajectory is subject to some special requirements to fulfil which it has to be suitably corrected by auxiliary collisions. In the present paper we prove that—at least when the relevant particles move in the equatorial plane and experience a single correcting collision—this mechanism does not work too. The energy of the final collision becomes unboundedly high only when the energies of the incoming particles do.
Canceling the Gravity Gradient Phase Shift in Atom Interferometry.
D'Amico, G; Rosi, G; Zhan, S; Cacciapuoti, L; Fattori, M; Tino, G M
2017-12-22
Gravity gradients represent a major obstacle in high-precision measurements by atom interferometry. Controlling their effects to the required stability and accuracy imposes very stringent requirements on the relative positioning of freely falling atomic clouds, as in the case of precise tests of Einstein's equivalence principle. We demonstrate a new method to exactly compensate the effects introduced by gravity gradients in a Raman-pulse atom interferometer. By shifting the frequency of the Raman lasers during the central π pulse, it is possible to cancel the initial position- and velocity-dependent phase shift produced by gravity gradients. We apply this technique to simultaneous interferometers positioned along the vertical direction and demonstrate a new method for measuring local gravity gradients that does not require precise knowledge of the relative position between the atomic clouds. Based on this method, we also propose an improved scheme to determine the Newtonian gravitational constant G towards the 10 ppm relative uncertainty.
Space processing experimental apparatus - A survey
NASA Technical Reports Server (NTRS)
Siebel, M. P.
1977-01-01
The processing of materials in a low-g environment was started approximately 10 years ago. This article surveys the apparatus developed during that period. A low-g environment occurs naturally in a free-flying spacecraft (e.g., in manned flights such as Apollo, Skylab, and ASTP); low-g conditions also occur in other free-falling bodies such as sounding rockets and drop tower capsules. Apparatus has been developed for all these craft. Most of the apparatus described serves to melt and resolidify materials in low g; the material may be contained or, by virtue of the environment, freely floating. Other apparatus for separation of intimately mixed components or species is also described. A general conclusion is drawn that the apparatus addresses only a few of the possibilities available, is still at the experimental stage, and is of laboratory scale. It is predicted that processes showing promise will be scaled up to derive economic advantages in the Shuttle era of space flight.
Can quantum probes satisfy the weak equivalence principle?
DOE Office of Scientific and Technical Information (OSTI.GOV)
Seveso, Luigi, E-mail: luigi.seveso@unimi.it; Paris, Matteo G.A.; INFN, Sezione di Milano, I-20133 Milano
We address the question whether quantum probes in a gravitational field can be considered as test particles obeying the weak equivalence principle (WEP). A formulation of the WEP is proposed which applies also in the quantum regime, while maintaining the physical content of its classical counterpart. Such formulation requires the introduction of a gravitational field not to modify the Fisher information about the mass of a freely-falling probe, extractable through measurements of its position. We discover that, while in a uniform field quantum probes satisfy our formulation of the WEP exactly, gravity gradients can encode nontrivial information about the particle’smore » mass in its wavefunction, leading to violations of the WEP. - Highlights: • Can quantum probes under gravity be approximated as test-bodies? • A formulation of the weak equivalence principle for quantum probes is proposed. • Quantum probes are found to violate it as a matter of principle.« less
Canceling the Gravity Gradient Phase Shift in Atom Interferometry
NASA Astrophysics Data System (ADS)
D'Amico, G.; Rosi, G.; Zhan, S.; Cacciapuoti, L.; Fattori, M.; Tino, G. M.
2017-12-01
Gravity gradients represent a major obstacle in high-precision measurements by atom interferometry. Controlling their effects to the required stability and accuracy imposes very stringent requirements on the relative positioning of freely falling atomic clouds, as in the case of precise tests of Einstein's equivalence principle. We demonstrate a new method to exactly compensate the effects introduced by gravity gradients in a Raman-pulse atom interferometer. By shifting the frequency of the Raman lasers during the central π pulse, it is possible to cancel the initial position- and velocity-dependent phase shift produced by gravity gradients. We apply this technique to simultaneous interferometers positioned along the vertical direction and demonstrate a new method for measuring local gravity gradients that does not require precise knowledge of the relative position between the atomic clouds. Based on this method, we also propose an improved scheme to determine the Newtonian gravitational constant G towards the 10 ppm relative uncertainty.
NASA Astrophysics Data System (ADS)
Park, Robert
2011-03-01
A remarkable scientific result that appears to violate natural law may portend a revolutionary advance in human knowledge. It is, however, more likely an experimental screw up. Error is normal; it can be reduced by repeating measurements and better design of controls, but the success and credibility of science is anchored in a culture of openness. Ideas and observations are freely exposed to independent testing and evaluation by others. What emerges is the book of nature. On its pages we find, if not a simple world, at least an orderly world, in which everything from the birth of stars to falling in love is governed by the same natural laws. These laws cannot be circumvented by any amount of piety or cleverness, they can be understood - with the possible exception of String Theory. For those who elect to work outside the scientific community, errors may go unrecognized. We will examine examples of this, including claims of perpetual motion and cancer caused by cell-phone radiation.
Task oriented training improves the balance outcome & reducing fall risk in diabetic population
Ghazal, Javeria; Malik, Arshad Nawaz; Amjad, Imran
2016-01-01
Objectives: The objective was to determine the balance impairments and to compare task oriented versus traditional balance training in fall reduction among diabetic patients. Methods: The randomized control trial with descriptive survey and 196 diabetic patients were recruited to assess balance impairments through purposive sampling technique. Eighteen patients were randomly allocated into two groups; task oriented balance training group TOB (n=8) and traditional balance training group TBT (n=10). The inclusion criteria were 30-50 years age bracket and diagnosed cases of Diabetes Mellitus with neuropathy. The demographics were taken through standardized & valid assessment tools include Berg Balance Scale and Functional Reach Test. The measurements were obtained at baseline, after 04 and 08 weeks of training. Results: The mean age of the participants was 49 ±6.79. The result shows that 165(84%) were at moderate risk of fall and 31(15%) were at mild risk of fall among total 196 diabetic patients. There was significant improvement (p <0.05) in task oriented balance training group for dynamic balance, anticipatory balance and reactive balance after 8 weeks of training as compare to traditional balance training. Conclusion: Task oriented balance training is effective in improving the dynamic, anticipator and reactive balance. The task oriented training reduces the risk of falling through enhancing balance outcome. PMID:27648053
The clinical utility of posturography.
Visser, Jasper E; Carpenter, Mark G; van der Kooij, Herman; Bloem, Bastiaan R
2008-11-01
Postural instability and falls are common and devastating features of ageing and many neurological, visual, vestibular or orthopedic disorders. Current management of these problems is hampered by the subjective and variable nature of the available clinical balance measures. In this narrative review, we discuss the clinical utility of posturography as a more objective and quantitative measure of balance and postural instability, focusing on several areas where clinicians presently experience the greatest difficulties in managing their patients: (a) to make an appropriate differential diagnosis in patients presenting with falls or balance impairment; (b) to reliably identify those subjects who are at risk of falling; (c) to objectively and quantitatively document the outcome of therapeutic interventions; and (d) to gain a better pathophysiological understanding of postural instability and falls, as a basis for the development of improved treatment strategies to prevent falling. In each of these fields, posturography offers several theoretical advantages and, when applied correctly, provides a useful tool to gain a better understanding of pathophysiological mechanisms in patients with balance disorders, at the group level. However, based on the available evidence, none of the existing techniques is currently able to significantly influence the clinical decision making in individual patients. We critically review the shortcomings of posturography as it is presently used, and conclude with several recommendations for future research.
Older Persons’ Perception of Risk of Falling: Implications for Fall-Prevention Campaigns
Hughes, Karen; van Beurden, Eric; Eakin, Elizabeth G.; Barnett, Lisa M.; Patterson, Elizabeth; Backhouse, Jan; Jones, Sue; Hauser, Darren; Beard, John R.; Newman, Beth
2008-01-01
Objectives. We examined older people’s attitudes about falls and implications for the design of fall-prevention awareness campaigns. Methods. We assessed data from (1) computer-assisted telephone surveys conducted in 2002 with Australians 60 years and older in Northern Rivers, New South Wales (site of a previous fall-prevention program; n=1601), and Wide Bay, Queensland (comparison community; n=1601), and (2) 8 focus groups (n=73). Results. Participants from the previous intervention site were less likely than were comparison participants to agree that falls are not preventable (odds ratio [OR]=0.76; 95% confidence interval [CI]=0.65, 0.90) and more likely to rate the prevention of falls a high priority (OR=1.31; 95% CI=1.09, 1.57). There was no difference between the groups for self-perceived risk of falls; more than 60% rated their risk as low. Those with a low perceived risk were more likely to be men, younger, partnered, and privately insured, and to report better health and no history of falls. Focus group data indicated that older people preferred messages that emphasized health and independence rather than falls. Conclusions. Although older people accepted traditional fall-prevention messages, most viewed them as not personally relevant. Messages that promote health and independence may be more effective. PMID:18172132
Quality of Austrian and Dutch Falls-Prevention Information: A Comparative Descriptive Study
ERIC Educational Resources Information Center
Schoberer, Daniela; Mijnarends, Donja M.; Fliedner, Monica; Halfens, Ruud J. G.; Lohrmann, Christa
2016-01-01
Objectives: The aim of this study was to evaluate and compare the quality of written patient information material available in Austrian and Dutch hospitals and nursing homes pertaining to falls prevention. Design: Comparative descriptive study design Setting: Hospitals and nursing homes in Austria and the Netherlands. Method: Written patient…
USDA-ARS?s Scientific Manuscript database
Diversification of farm enterprises is important to maintain sustainable production systems. Systems that integrate crops and livestock may prove beneficial to each enterprise. Our objectives were to determine the effects of annual crops grazed in the fall and early-winter period on cow and calf gro...
Implementing a Community-Based Falls-Prevention Program: From Drawing Board to Reality
ERIC Educational Resources Information Center
Filiatrault, Johanne; Parisien, Manon; Laforest, Sophie; Genest, Carole; Gauvin, Lise; Fournier, Michel; Trickey, Francine; Robitaille, Yvonne
2007-01-01
Several studies have demonstrated the efficacy of falls-prevention programs designed for community-dwelling seniors using randomized designs. However, little is known about the feasibility of implementing these programs under natural conditions and about the success of these programs when delivered under such conditions. The objectives of this…
1995-06-23
provides the results of the audit of one project, valued at $1.8 million, for the repair of roads on Sheppard Air Force Base, Wichita Falls, Texas. The ... audit also assessed the adequacy of the management control program as it applied to the audit objectives.
Nutrient losses from Fall and Winter-applied manure: Effects of timing and soil temperature
USDA-ARS?s Scientific Manuscript database
Soil temperature is a major environmental factor that affects both the infiltration of meltwater and precipitation, and nutrient cycling. The objectives of this study were to determine nutrient losses in runoff and leachate from fall and winter-applied dairy manure based on the soil temperature at t...
Nutrient losses from fall- and winter-applied manure: effects of timing and soil temperature
USDA-ARS?s Scientific Manuscript database
Soil temperature is a major environmental factor that affects meltwater and precipitation infiltration and nutrient cycling. The objective of this study was to determine nutrient losses in runoff and leachate from fall- and winter-applied dairy manure as affected by soil temperature at the time of a...
USDA-ARS?s Scientific Manuscript database
OBJECTIVE: To test whether a long term, structured physical activity program compared with a health education program reduces the risk of serious fall injuries among sedentary older people with functional limitations. DESIGN: Multicenter, single blinded randomized trial (Lifestyle Interventions and ...
Johnson County Community College Fall 2001 New Student Survey.
ERIC Educational Resources Information Center
Weglarz, Shirley G.
This survey of new Johnson County Community College (JCCC) (Kansas) students was conducted in fall 2001 to determine new students' educational objectives, and what factors influenced new students' decisions to attend JCCC. Questions were also asked about the JCCC Student Success Center and new students' preferences for various media to provide…
The Rise and Fall of Energy Education.
ERIC Educational Resources Information Center
Petrock, Edith M.
This paper discusses the rise and fall of energy education, justifies the commitment to achieve the goals of energy education, and suggests some strategies for accomplishing this objective. The rise of energy education is first discussed. Energy is not a newcomer to the K-12 school instructional program. Energy sources, forms, states, and uses…
DOT National Transportation Integrated Search
1997-06-18
This document has been prepared as part of the New York State Department of Transportation (NYSDOT) Buffalo and Niagara Falls Intelligent Transportation Systems Study. The primary objective of this working paper is to define and document transportati...
Why did the apple fall? A new model to explain Einstein’s gravity
NASA Astrophysics Data System (ADS)
Stannard, Warren; Blair, David; Zadnik, Marjan; Kaur, Tejinder
2017-01-01
Newton described gravity as an attractive force between two masses but Einstein’s General Theory of Relativity provides a very different explanation. Implicit in Einstein’s theory is the idea that gravitational effects are the result of a distortion in the shape of space-time. Despite its elegance, Einstein’s concept of gravity is rarely encountered outside of an advanced physics course as it is often considered to be too complex and too mathematical. This paper describes a new conceptual and quantitative model of gravity based on General Relativity at a level most science students should be able to understand. The model illustrates geodesics using analogies with paths of navigation on the surface of the Earth. This is extended to space and time maps incorporating the time warping effects of General Relativity. Using basic geometry, the geodesic path of a falling object near the surface of the Earth is found. From this the acceleration of an object in free fall is calculated. The model presented in this paper can answer the question, ‘Why do things fall?’ without resorting to Newton’s gravitational force.
NASA Astrophysics Data System (ADS)
Michon, Frédéric; Aarts, Arno; Holzhammer, Tobias; Ruther, Patrick; Borghs, Gustaaf; McNaughton, Bruce; Kloosterman, Fabian
2016-08-01
Objective. Understanding how neuronal assemblies underlie cognitive function is a fundamental question in system neuroscience. It poses the technical challenge to monitor the activity of populations of neurons, potentially widely separated, in relation to behaviour. In this paper, we present a new system which aims at simultaneously recording from a large population of neurons from multiple separated brain regions in freely behaving animals. Approach. The concept of the new device is to combine the benefits of two existing electrophysiological techniques, i.e. the flexibility and modularity of micro-drive arrays and the high sampling ability of electrode-dense silicon probes. Main results. Newly engineered long bendable silicon probes were integrated into a micro-drive array. The resulting device can carry up to 16 independently movable silicon probes, each carrying 16 recording sites. Populations of neurons were recorded simultaneously in multiple cortical and/or hippocampal sites in two freely behaving implanted rats. Significance. Current approaches to monitor neuronal activity either allow to flexibly record from multiple widely separated brain regions (micro-drive arrays) but with a limited sampling density or to provide denser sampling at the expense of a flexible placement in multiple brain regions (neural probes). By combining these two approaches and their benefits, we present an alternative solution for flexible and simultaneous recordings from widely distributed populations of neurons in freely behaving rats.
In vivo recording of aerodynamic force with an aerodynamic force platform: from drones to birds.
Lentink, David; Haselsteiner, Andreas F; Ingersoll, Rivers
2015-03-06
Flapping wings enable flying animals and biomimetic robots to generate elevated aerodynamic forces. Measurements that demonstrate this capability are based on experiments with tethered robots and animals, and indirect force calculations based on measured kinematics or airflow during free flight. Remarkably, there exists no method to measure these forces directly during free flight. Such in vivo recordings in freely behaving animals are essential to better understand the precise aerodynamic function of their flapping wings, in particular during the downstroke versus upstroke. Here, we demonstrate a new aerodynamic force platform (AFP) for non-intrusive aerodynamic force measurement in freely flying animals and robots. The platform encloses the animal or object that generates fluid force with a physical control surface, which mechanically integrates the net aerodynamic force that is transferred to the earth. Using a straightforward analytical solution of the Navier-Stokes equation, we verified that the method is accurate. We subsequently validated the method with a quadcopter that is suspended in the AFP and generates unsteady thrust profiles. These independent measurements confirm that the AFP is indeed accurate. We demonstrate the effectiveness of the AFP by studying aerodynamic weight support of a freely flying bird in vivo. These measurements confirm earlier findings based on kinematics and flow measurements, which suggest that the avian downstroke, not the upstroke, is primarily responsible for body weight support during take-off and landing.
Razjouyan, Javad; Grewal, Gurtej Singh; Rishel, Cindy; Parthasarathy, Sairam; Mohler, Jane; Najafi, Bijan
2017-07-01
Growing concern for falls in acute care settings could be addressed with objective evaluation of fall risk. The current proof-of-concept study evaluated the feasibility of using a chest-worn sensor during hospitalization to determine fall risk. Physical activity and heart rate variability (HRV) of 31 volunteers admitted to a 29-bed adult inpatient unit were recorded using a single chest-worn sensor. Sensor data during the first 24-hour recording were analyzed. Participants were stratified using the Hendrich II fall risk assessment into high and low fall risk groups. Univariate analysis revealed age, daytime activity, nighttime side lying posture, and HRV were significantly different between groups. Results suggest feasibility of wearable technology to consciously monitor physical activity, sleep postures, and HRV as potential markers of fall risk in the acute care setting. Further study is warranted to confirm the results and examine the efficacy of the proposed wearable technology to manage falls in hospitals. [Journal of Gerontological Nursing, 43(7), 53-62.]. Copyright 2017, SLACK Incorporated.
The development of a fear of falling interdisciplinary intervention program
Gomez, Fernando; Curcio, Carmen-Lucia
2007-01-01
Objective: To describe the development process of a protocol for a fear of falling interdisciplinary intervention program based on the main factors associated with fear of falling. Design/methods: The process of developing a protocol consisted of defining the target population, selecting the initial assessment components, adapting the intervention program based on findings about fear of falling and restriction of activities in this population. Settings: University-affiliated outpatient vertigo, dizziness and falls clinic in coffee-growers zone of Colombian Andes Mountains. Results: An intervention program was developed based on three main falling conceptual models. A medical intervention, based on a biomedical and pathophysiological model, a physiotherapeutic intervention based on a postural control model and a psychological intervention based on a biological-behavioral model. Conclusion: This interdisciplinary fear of falling intervention program developed is based on particular characteristics of target population, with differences in the inclusion criteria and the program intervention components; with emphasis on medical (recurrent falls and dizziness evaluation and management), psychological (cognitive-behavioral therapy) and physiotherapeutic (balance and transfers training) components. PMID:18225468
Falls and age in patients with Alzheimer's disease.
Bassiony, Medhat M; Rosenblatt, Adam; Baker, Alva; Steinberg, Martin; Steele, Cynthia D; Sheppard, Jeanie-Marie E; Lyketsos, Constantine G
2004-08-01
The study's objective was to estimate the prevalence of falls in community-residing patients with Alzheimer's disease (AD) and to investigate the relationship between falls and age in AD. This was a study of 326 community-residing patients with AD according to National Institute of Neurological and Communicative Disorders and Stroke and Alzheimer's Disease and Related Disorders Association criteria. The patients and their caregivers were asked about falls, behavioral disturbances, and medication use within the last 2 weeks. The patients were also rated on standardized measures of cognitive impairment, stage of dementia, depression, daily activities, general health, and extrapyramidal symptoms. Falls occurred in 24 (7.4%) patients with AD during the last 2 weeks. Using multiple logistic regression analyses, falls were independently associated with old age (odds ratio = 1.2; p = .03; 95% confidence interval = 1.0 to 1.4) but not with other variables examined. The authors conclude that falls in community-residing patients with AD are significantly associated with old age. Population-based prospective studies are needed to investigate further the risk factors for falls in AD.
Bea, Jennifer W.; Zhao, Qiuhong; Cauley, Jane A.; LaCroix, Andrea Z.; Bassford, Tamsen; Lewis, Cora E.; Jackson, Rebecca D.; Tylavsky, Frances A.; Chen, Zhao
2010-01-01
Objective Loss of lean body mass with aging may contribute to falls and fractures. The objective of this analysis was to determine if taking postmenopausal hormone therapy (HT: estrogen plus progestogen therapy, EPT or estrogen therapy alone, ET) favorably affects age-related changes in lean body mass and if these changes partially account for decreased falls or fractures with HT. Methods Participants randomly assigned to either EPT (n=543) or control (n=471) and ET (n= 453) or control (n= 474) and receiving dual-energy X-ray absorptiometry (DXA) scans to estimate body composition during the Women’s Health Initiative (WHI) were evaluated. Falls and fracture occurrence were obtained by annual self-report. Fractures were confirmed by clinical chart review. Results At 6yrs post-randomization, lean body mass was not different between HT and control groups. Although lean body mass positively influenced BMD, independent of HT status, the preserved lean body mass observed in the HT arms in the first 3 years did not significantly contribute to models evaluating HT influence on falls and fractures between years 3 and 6. Women taking at least 80% of their medication in the HT arms demonstrated fewer falls compared to placebo; this difference was not attributable to change in lean body mass. Conclusions Despite early preservation of lean body mass with HT (3years), HT did not ameliorate long-term (6 years) loss in lean body mass with aging. PMID:20689466
Fall Prevention in Apprentice Carpenters
Kaskutas, Vicki; Dale, Ann Marie; Lipscomb, Hester; Gaal, John; Fuchs, Mark; Evanoff, Bradley; Faucette, Julia; Gillen, Marion; Deych, Elena
2013-01-01
Objectives Falls from heights are a leading cause of mortality and morbidity in the construction industry, especially among inexperienced workers. We surveyed apprentice carpenters to identify individual and organizational factors associated with falls from heights. Methods We developed a 72-item fall prevention survey with multiple domains including fall experience, fall prevention knowledge, risk perceptions, confidence in ability to prevent falls, training experience, and perceptions of the safety climate and crew safety behaviors. We administered the questionnaire to apprentice carpenters in this cross-sectional study. Results Of the 1,025 respondents, 51% knew someone who had fallen from height at work and 16% had personally fallen in the past year, with ladders accounting for most of the falls. Despite participation in school-based and on-the-job training, fall prevention knowledge was poor. Ladders were perceived as low risk and ladder training was rare. Apprentices reported high levels of unsafe fall-related behaviors on their work crews. Apprentices working residential construction were more likely to fall than those working commercial construction, as were apprentices working on crews with fewer senior carpenters to provide mentorship, and those reporting more unsafe behaviors among fellow workers. Conclusions Despite participation in a formal apprenticeship program, many apprentices work at heights without adequate preparation and subsequently experience falls. Apprenticeship programs can improve the timing and content of fall prevention training. This study suggests that organizational changes in building practices, mentorship, and safety culture must also occur in order to decrease worker falls from heights. PMID:19953214
Optical Telescope System-Level Design Considerations for a Space-Based Gravitational Wave Mission
NASA Technical Reports Server (NTRS)
Livas, Jeffrey C.; Sankar, Shannon R.
2016-01-01
The study of the Universe through gravitational waves will yield a revolutionary new perspective on the Universe, which has been intensely studied using electromagnetic signals in many wavelength bands. A space-based gravitational wave observatory will enable access to a rich array of astrophysical sources in the measurement band from 0.1 to 100 mHz, and nicely complement observations from ground-based detectors as well as pulsar timing arrays by sampling a different range of compact object masses and astrophysical processes. The observatory measures gravitational radiation by precisely monitoring the tiny change in the proper distance between pairs of freely falling proof masses. These masses are separated by millions of kilometers and, using a laser heterodyne interferometric technique, the change in their proper separation is detected to approx. 10 pm over timescales of 1000 seconds, a fractional precision of better than one part in 10(exp 19). Optical telescopes are essential for the implementation of this precision displacement measurement. In this paper we describe some of the key system level design considerations for the telescope subsystem in a mission context. The reference mission for this purpose is taken to be the enhanced Laser Interferometry Space Antenna mission (eLISA), a strong candidate for the European Space Agency's Cosmic Visions L3 launch opportunity in 2034. We will review the flow-down of observatory level requirements to the telescope subsystem, particularly pertaining to the effects of telescope dimensional stability and scattered light suppression, two performance specifications which are somewhat different from the usual requirements for an image forming telescope.
Logan, Sarah
2016-01-01
Objective To describe the longitudinal characteristics of unintentional fall accidents using a representative population-based sample of Korean adults. Methods We examined data from the Korean Community Health Survey from 2008 to 2013. Univariate analysis and multivariable logistic regression were used to identify the characteristics of fall accidents in adults. Results Between 2008 and 2013, the incidence rate of fall accidents requiring medical treatment increased from 1,248 to 3,423 per 100,000 people (p<0.001), while the proportion of indoor fall accidents decreased from 38.12% to 23.16% (p<0.001). Females had more annual fall accidents than males (p<0.001). The major reason for fall accidents was slippery floors (33.7% in 2011 and 36.3% in 2013). Between 2008 and 2010, variables associated with higher fall accident risk included specific months (August and September), old age, female gender, current drinker, current smoker, diabetes, osteoarthritis, osteoporosis, and depression. A high level of education and living with a partner were negatively associated with fall accident risk. In 2013, people experiencing more than 1 fall accident felt more fear of falling than those having no fall accidents (odds ratio [OR] for 1 fall, 2.12; 95% confidence interval [CI], 2.04–2.12; OR for more than 2 falls, 2.97; 95% CI, 2.83–3.10). Conclusion The occurrence of fall accidents has consistently increased in Korea from 2008 to 2013. Future intervention studies are needed to reduce the increasing incidence rates of fall accidents in community dwelling adults. PMID:27606272
Schonnop, Rebecca; Yang, Yijian; Feldman, Fabio; Robinson, Erin; Loughin, Marie; Robinovitch, Stephen N
2013-11-19
Falls cause more than 60% of head injuries in older adults. Lack of objective evidence on the circumstances of these events is a barrier to prevention. We analyzed video footage to determine the frequency of and risk factors for head impact during falls in older adults in 2 long-term care facilities. Over 39 months, we captured on video 227 falls involving 133 residents. We used a validated questionnaire to analyze the mechanisms of each fall. We then examined whether the probability for head impact was associated with upper-limb protective responses (hand impact) and fall direction. Head impact occurred in 37% of falls, usually onto a vinyl or linoleum floor. Hand impact occurred in 74% of falls but had no significant effect on the probability of head impact (p = 0.3). An increased probability of head impact was associated with a forward initial fall direction, compared with backward falls (odds ratio [OR] 2.7, 95% confidence interval [CI] 1.3-5.9) or sideways falls (OR 2.8, 95% CI 1.2-6.3). In 36% of sideways falls, residents rotated to land backwards, which reduced the probability of head impact (OR 0.2, 95% CI 0.04-0.8). Head impact was common in observed falls in older adults living in long-term care facilities, particularly in forward falls. Backward rotation during descent appeared to be protective, but hand impact was not. Attention to upper-limb strength and teaching rotational falling techniques (as in martial arts training) may reduce fall-related head injuries in older adults.
Loganathan, Annaletchumy; Ng, Chirk Jenn; Tan, Maw Pin; Low, Wah Yun
2015-01-01
Objective To explore the barriers faced by healthcare professionals (HCPs) in managing falls among older people (aged above 60 years) who have a high risk of falling. Research design The study used a qualitative methodology, comprising 10 in-depth interviews and two focus group discussions. A semistructured topic guide was used to facilitate the interviews, which were audio recorded, transcribed verbatim and checked for accuracy. Data were analysed thematically using WeftQDA software. Participants 20 HCPs who managed falls in older people. Setting This study was conducted at the Primary Care Clinic in the University Malaya Medical Centre (UMMC), Malaysia. Results Four categories of barriers emerged—these were related to perceived barriers for older people, HCPs’ barriers, lack of caregiver support and healthcare system barriers. HCPs perceived that older people normalised falls, felt stigmatised, were fatalistic, as well as in denial regarding falls-related advice. HCPs themselves trivialised falls and lacked the skills to manage falls. Rehabilitation was impeded by premature decisions to admit older people to nursing homes. Lastly, there was a lack of healthcare providers as well as a dearth of fall education and training on fall prevention for HCPs. Conclusions This study identified barriers that explain poor fall management in older people with a high risk of falls. The lack of structured fall prevention guidelines and insufficient training in fall management made HCPs unable to advise patients on how to prevent falls. The findings of this study warrant evidence-based structured fall prevention intervention targeted to patients as well as to HCPs. PMID:26546140
2011-01-01
Background Objective measurements can be used to identify people with risks of falls, but many frail elderly adults cannot complete physical performance tests. The study examined the relationship between a subjective risk rating of specific tasks (SRRST) to screen for fall risks and falls and fall-related fractures in frail elderly people. Methods The SRRST was investigated in 5,062 individuals aged 65 years or older who were utilized day-care services. The SRRST comprised 7 dichotomous questions to screen for fall risks during movements and behaviours such as walking, transferring, and wandering. The history of falls and fall-related fractures during the previous year was reported by participants or determined from an interview with the participant's family and care staff. Results All SRRST items showed significant differences between the participants with and without falls and fall-related fractures. In multiple logistic regression analysis adjusted for age, sex, diseases, and behavioural variables, the SRRST score was independently associated with history of falls and fractures. Odds ratios for those in the high-risk SRRST group (≥ 5 points) compared with the no risk SRRST group (0 point) were 6.15 (p < 0.01) for a single fall, 15.04 (p < 0.01) for recurrent falls, and 5.05 (p < 0.01) for fall-related fractures. The results remained essentially unchanged in subgroup analysis accounting for locomotion status. Conclusion These results suggest that subjective ratings by care staff can be utilized to determine the risks of falls and fall-related fractures in the frail elderly, however, these preliminary results require confirmation in further prospective research. PMID:21838891
Chou, Kee-Lee; Chi, Iris
2008-09-01
The objective of the current study is to investigate the link between depression and fear of falling in Hong Kong Chinese older adults in primary are settings. Using longitudinal data collected on 321 Chinese primary care patients 65 years of age and older, the authors investigated the reciprocal relationship between fear of falling and depression and examined whether functional disability and social functioning mediated the link between fear of falling and depression. Participants were recruited from three primary care units in Hong Kong. Subjects were assessed in Cantonese by two trained assessors with Minimum Data Set-Home Care twice over a period of one year. Findings revealed that fear of falling at baseline significantly predicted depression at 12 month follow-up assessment after age, gender, marital status, education and depression at baseline were adjusted, but depression at baseline did not predict fear of falling at 12 months after fear of falling at baseline was adjusted. Moreover, social functioning mediated the impact of fear of falling on depression. The findings presented here indicate that fear of falling potentially increases the risk of depression in Chinese older adults in primary care settings.
Translating a Fall Prevention Intervention Into Practice: A Randomized Community Trial
Peterson, Donna J.; Christiansen, Ann L.; Mahoney, Jane; Laud, Purushottam; Layde, Peter M.
2015-01-01
Objectives. We examined whether community translation of an effective evidence-based fall prevention program via standard monetary support can produce a community-wide reduction in fall injuries in older adults and evaluated whether an enhanced version with added technical support and capacity building amplified the fall reduction effect. Methods. We completed a randomized controlled community trial among adults aged 65 and older in (1) 10 control communities receiving no special resources or guidance on fall prevention, (2) 5 standard support communities receiving modest funding to implement Stepping On, and (3) 5 enhanced support communities receiving funding and technical support. The primary outcome was hospital inpatient and emergency department discharges for falls, examined with Poisson regression. Results. Compared with control communities, standard and enhanced support communities showed significantly higher community-wide reductions (9% and 8%, respectively) in fall injuries from baseline (2007–2008) to follow-up (2010–2011). No significant difference was found between enhanced and standard support communities. Conclusions. Population-based fall prevention interventions can be effective when implemented in community settings. More research is needed to identify the barriers and facilitators that influence the successful adoption and implementation of fall prevention interventions into broad community practice. PMID:25602891
Johansson, Jonas; Nordström, Anna; Nordström, Peter
2016-06-01
As 90% of fractures are caused by falls, and as fractures are more common in elderly women than in elderly men, a better understanding of potential sex differences in fall rates and underlying mechanisms is needed. The purpose of this study was to determine whether women are more prone than men to falling, and to evaluate whether the risk of falling is associated with variations in gait patterns. The cohort for this prospective observational study consisted of 1390 community-dwelling men and women aged 70 years, examined in a health survey between July 2012 and November 2014. Gait patterns were measured using a computerized walkway system during normal-speed, fast-speed, and dual-task trials. Triaxial accelerometers were used to collect objective data on physical activity, and self-reported fall data were collected by telephone 6 and 12 months after examination. Incident low-energy falls were defined as unexpected events in which participants came to rest on the ground. During the follow-up period, 148 study participants (88 women, 60 men; P = .01) reported falls. After adjusting for multiple confounders, including objective measures of physical activity, socioeconomic factors, cardiovascular disease, and cognitive function, the odds ratio for falling in women was 1.49 (95% confidence interval [CI] 1.02-2.19). Variations in gait pattern were significantly (20%-40%) increased in fallers compared with nonfallers during the dual-task trial for step width, step length, stride length, step time, stance time, stride velocity, and single support time (all P < .05). Furthermore, women showed 15% to 35% increased variability in all of these gait parameters during the dual-task trial compared with men (all P < .01). In the present cohort, 70-year-old women were at greater risk of falls compared with their male counterparts. This increased risk was associated with increased variation in gait pattern during dual-task activities, and may contribute to women's greater fracture risk compared with men. Copyright © 2016 AMDA – The Society for Post-Acute and Long-Term Care Medicine. Published by Elsevier Inc. All rights reserved.
An assistance device to help people with trunk impairment maintain posture.
Ogura, Tomoka; Itami, Taku; Yano, Ken'ichi; Mori, Ichidai; Kameda, Kazuhiro
2017-07-01
People with trunk impairment cannot lean forward because of the dysfunction of the trunk resulting from events such as cervical cord injury (CCI). It is therefore difficult for such people to work at a table because they may easily fall from their wheelchair, and it is also hard for them to return to their original position. This limits the activities of daily living (ADLs) of people with trunk impairment. These problems can be solved to some extent with equipment such as a wheelchair belt or a spinal orthosis that can help the person to maintain his or her posture. However, people cannot move freely with this equipment. Furthermore, if this equipment is used for a long time, there is a risk of physical pain and skin issues. In this study, we developed a device that assists the trunk of people with trunk impairment when they lean forward. This device supports people with trunk impairment so that they may take their meals at the table and prevents them from falling over their wheelchair without hindering their daily performance when they are sitting normally. The effectiveness of our proposed device was verified by experiments involving having a meal, operating a wheelchair, and colliding with a curb. Our device can help people with trunk impairment by improving their ADLs and quality of life (QOL).
Agmon, Maayan; Lavie, Limor; Doumas, Michail
2017-06-01
Degraded hearing in older adults has been associated with reduced postural control and higher risk of falls. Both hearing loss (HL) and falls have dramatic effects on older persons' quality of life (QoL). A large body of research explored the comorbidity between the two domains. The aim of the current review is to describe the comorbidity between HL and objective measures of postural control, to offer potential mechanisms underlying this relationship, and to discuss the clinical implications of this comorbidity. PubMed and Google Scholar were systematically searched for articles published in English up until October 15, 2015, using combinations of the following strings and search words: for hearing: Hearing loss, "Hearing loss," hearing, presbycusis; for postural control: postural control, gait, postural balance, fall, walking; and for age: elderly, older adults. Of 211 screened articles, 7 were included in the systematic review. A significant, positive association between HL and several objective measures of postural control was found in all seven studies, even after controlling for major covariates. Severity of hearing impairment was connected to higher prevalence of difficulties in walking and falls. Physiological, cognitive, and behavioral processes that may influence auditory system and postural control were suggested as potential explanations for the association between HL and postural control. There is evidence for the independent relationship between HL and objective measures of postural control in the elderly. However, a more comprehensive understanding of the mechanisms underlying this relationship is yet to be elucidated. Concurrent diagnosis, treatment, and rehabilitation of these two modalities may reduce falls and increase QoL in older adults. American Academy of Audiology
Learning about Gravity I. Free Fall: A Guide for Teachers and Curriculum Developers
NASA Astrophysics Data System (ADS)
Kavanagh, Claudine; Sneider, Cary
This article is the first of a two-part review of research on children's and adults understanding of gravity and on how best to teach gravity concepts to students and teachers. This first article concerns free fall—how and why objects fall when they are dropped. The review begins with a brief historical sketch of how these ideas were developed in human history, followed by a summary of the relevant standards and benchmarks. The body of research is organized by the nature of the findings, beginning with studies of the youngest children, followed by older students, adults, and teachers. Although a diversity of misconceptions are found at all age levels, in general children, between the ages of 7 and 9 progress from the idea that things fall because they're not supported to things fall because they're "heavy." Between the ages of 9 and 13, students begin to use the term "gravity," an unseen force, to explain falling, such as "gravity acts just on heavy objects," or "things fall because air is pushing them down." Surprisingly, many high school and college students who can successfully solve numerical problems involving gravity hold qualitative misconceptions similar to those held by much younger students. The finding that even college physics students have significant misconceptions about free fall underscores the importance of effective teaching at the middle and high school levels. Some studies have found that few teachers are aware of their students' misconceptions or know what to do about them. A few studies have reported success in helping students shed their misconceptions, leading to promising recommendations for curriculum development and teaching.
Fall-induced spinal cord injury: External causes and implications for prevention
Tang, Ying; Allen, Victoria; DeVivo, Michael J
2016-01-01
Objective To document the demographic and clinical profile of persons who sustained spinal cord injury (SCI) as a result of accidental falls and to determine the usual circumstances surrounding the fall-induced SCI. Design Cohort study. Setting 21 SCI Model Systems centers throughout the United States. Participants 6,408 individuals with traumatic SCI between 2005 and 2014 were recruited from the National SCI Database. 1,877 (29%) of them were injuries caused by falls. Interventions Not applicable. Outcomes Measures External causes of injury documented by the International Classification of Diseases, 10th revision, Clinical Modification (ICD-10-CM). Results Falls on the same level from slipping, tripping, and stumbling were the most common cause of fall-induced SCI (20%), followed by falls from building (16%), stairs and steps (16%), and ladder (9%). People who were 61 years of age and older had the highest frequency of falls on the same level, while those aged 16–45 years had a higher percentage of falls from buildings, usually work-related. The mechanisms of falls also varied by sex and race. Associated injury and vertebral injury occurred frequently among falls from buildings and ladders. High falls were more likely to be work-related and result in thoracic and complete injury, while low falls were more commonly associated with cervical and motor functionally incomplete injury. Conclusion The study findings of different mechanisms of falls by age, sex, race and medical consequences provide an insight for future interventions aimed at high risk persons, activities, and environmental factors for preventing or reducing fall-induced SCI. PMID:25832327
Falls in People with Multiple Sclerosis Compared with Falls in Healthy Controls
Mazumder, Rajarshi; Murchison, Charles; Bourdette, Dennis; Cameron, Michelle
2014-01-01
Objective To compare the risk, circumstances, consequences and causes of prospectively recorded falls between people with multiple sclerosis (PwMS) and healthy controls of similar age and gender. Methods 58 PwMS and 58 healthy controls, who are community-dwelling, were recruited in this 6-month prospective cohort study. 90% of PwMS and 84% of healthy controls completed the study. Participants counted falls prospectively using fall calendars and noted fall location, fall-related injuries, and the cause of the falls. Kaplan Meier survival analysis and log-rank tests were performed to compare the distributions of survival without falling between PwMS and healthy controls. Results 40.8% of controls and 71.2% of PwMS fell at least once. 48.1% of PwMS and 18.4% of healthy controls fell at least twice. 42.3% of PwMS and 20.4% of health controls sustained a fall-related injury. After adjusting for age and gender, the time to first fall (HR: 1.87, p = 0.033) and the time to recurrent falls (HR: 2.87, p = 0.0082) were significantly different between PwMS and healthy controls. PwMS reported an almost equal number of falls inside and outside, 86% of the falls in healthy controls were outside. Healthy controls were more likely to fall due to slipping on a slippery surface (39.5% vs 10.4%). PwMS more often attributed falls to distraction (31% vs 7%) and uniquely attributed falls to fatigue or heat. Conclusions Fall risk, circumstances, consequences, and causes are different for PwMS than for healthy people of the same age and gender. PwMS fall more, are more likely to be injured by a fall, and often fall indoors. PwMS, but not healthy controls, frequently fall because they are distracted, fatigued or hot. PMID:25254633
Epidemiology of Fall Injury in Rural Bangladesh
Wadhwaniya, Shirin; Alonge, Olakunle; Ul Baset, Md. Kamran; Chowdhury, Salim; Bhuiyan, Al-Amin; Hyder, Adnan A.
2017-01-01
Globally, falls are the second leading cause of unintentional injury deaths, with 80% occurring in low-and middle-income countries. The overall objective of this study is to describe the burden and risk factors of falls in rural Bangladesh. In 2013, a large household survey covering a population of 1,169,593 was conducted in seven rural sub-districts of Bangladesh to assess the burden of all injuries, including falls. The recall periods for non-fatal and fatal injuries were six and 12 months, respectively. Descriptive, bivariate and multiple logistic regression analyses were conducted. The rates of non-fatal and fatal falls were 36.3 per 1000 and 5 per 100,000 population, respectively. The rates of both fatal and non-fatal falls were highest among the elderly. The risk of non-fatal falls was higher at extremes of age. Lower limb and waist injuries were frequent following a fall. Head injuries were frequent among infants (35%), while lower limb and waist injuries were frequent among the elderly (>65 years old). Injuries to all body parts (except the waist) were most frequent among men. More than half of all non-fatal falls occurred in a home environment. The injury patterns and risk factors of non-fatal falls differ by sociodemographic factors. PMID:28796160
Epidemiology of Fall Injury in Rural Bangladesh.
Wadhwaniya, Shirin; Alonge, Olakunle; Ul Baset, Md Kamran; Chowdhury, Salim; Bhuiyan, Al-Amin; Hyder, Adnan A
2017-08-10
Globally, falls are the second leading cause of unintentional injury deaths, with 80% occurring in low-and middle-income countries. The overall objective of this study is to describe the burden and risk factors of falls in rural Bangladesh. In 2013, a large household survey covering a population of 1,169,593 was conducted in seven rural sub-districts of Bangladesh to assess the burden of all injuries, including falls. The recall periods for non-fatal and fatal injuries were six and 12 months, respectively. Descriptive, bivariate and multiple logistic regression analyses were conducted. The rates of non-fatal and fatal falls were 36.3 per 1000 and 5 per 100,000 population, respectively. The rates of both fatal and non-fatal falls were highest among the elderly. The risk of non-fatal falls was higher at extremes of age. Lower limb and waist injuries were frequent following a fall. Head injuries were frequent among infants (35%), while lower limb and waist injuries were frequent among the elderly (>65 years old). Injuries to all body parts (except the waist) were most frequent among men. More than half of all non-fatal falls occurred in a home environment. The injury patterns and risk factors of non-fatal falls differ by sociodemographic factors.
Effect of a Multidisciplinary Fall Risk Assessment on Falls Among Neurology Inpatients
Hunderfund, Andrea N. Leep; Sweeney, Cynthia M.; Mandrekar, Jayawant N.; Johnson, LeAnn M.; Britton, Jeffrey W.
2011-01-01
OBJECTIVE: To evaluate whether the addition of a physician assessment of patient fall risk at admission would reduce inpatient falls on a tertiary hospital neurology inpatient unit. PATIENTS AND METHODS: A physician fall risk assessment was added to the existing risk assessment process (clinical nurse evaluation and Hendrich II Fall Risk Model score with specific fall prevention measures for patients at risk). An order to select either “Patient is” or “Patient is not at high risk of falls by physician assessment” was added to the physician electronic admission order set. Nurses and physicians were instructed to reach consensus when assessments differed. Full implementation occurred in second-quarter 2008. Preimplementation (January 1, 2006, to March 31, 2008) and postimplementation (April 1, 2008, to December 31, 2009) rates of falls were compared on the neurology inpatient unit and on 6 other medical units that did not receive intervention. RESULTS: The rate of falls during the 7 quarters after full implementation was significantly lower than that during the 9 preceding quarters (4.12 vs 5.69 falls per 1000 patient-days; P=.04), whereas the rate of falls on other medical units did not significantly change (2.99 vs 3.33 falls per 1000 patient-days; P=.24, Poisson test). The consensus risk assessment at admission correctly identified patients at risk for falls (14/325 at-risk patients fell vs 0/147 low-risk patients; P=.01, χ2 test), but the Hendrich II Fall Risk Model score, nurse, and physician assessments individually did not. CONCLUSION: A multidisciplinary approach to fall risk assessment is feasible, correctly identifies patients at risk, and was associated with a reduction in inpatient falls. PMID:21193651
Chang, John T; Morton, Sally C; Rubenstein, Laurence Z; Mojica, Walter A; Maglione, Margaret; Suttorp, Marika J; Roth, Elizabeth A; Shekelle, Paul G
2004-01-01
Objective To assess the relative effectiveness of interventions to prevent falls in older adults to either a usual care group or control group. Design Systematic review and meta-analyses. Data sources Medline, HealthSTAR, Embase, the Cochrane Library, other health related databases, and the reference lists from review articles and systematic reviews. Data extraction Components of falls intervention: multifactorial falls risk assessment with management programme, exercise, environmental modifications, or education. Results 40 trials were identified. A random effects analysis combining trials with risk ratio data showed a reduction in the risk of falling (risk ratio 0.88, 95% confidence interval 0.82 to 0.95), whereas combining trials with incidence rate data showed a reduction in the monthly rate of falling (incidence rate ratio 0.80, 0.72 to 0.88). The effect of individual components was assessed by meta-regression. A multifactorial falls risk assessment and management programme was the most effective component on risk of falling (0.82, 0.72 to 0.94, number needed to treat 11) and monthly fall rate (0.63, 0.49 to 0.83; 11.8 fewer falls in treatment group per 100 patients per month). Exercise interventions also had a beneficial effect on the risk of falling (0.86, 0.75 to 0.99, number needed to treat 16) and monthly fall rate (0.86, 0.73 to 1.01; 2.7). Conclusions Interventions to prevent falls in older adults are effective in reducing both the risk of falling and the monthly rate of falling. The most effective intervention was a multifactorial falls risk assessment and management programme. Exercise programmes were also effective in reducing the risk of falling. PMID:15031239
Functional Performance As a Predictor of Injurious Falls Among Older Adults
Ward, Rachel E.; Leveille, Suzanne G.; Beauchamp, Marla K.; Travison, Thomas; Alexander, Neil; Jette, Alan M.; Bean, Jonathan F.
2014-01-01
OBJECTIVES Guidelines for falls risk assessment include functional performance although evidence supporting specific tests for predicting injurious falls is lacking. We investigated whether a performance battery/its components aid in predicting injurious falls. DESIGN Longitudinal analysis; prospective cohort study. SETTING Clinical site. PARTICIPANTS 755 Boston area community-dwelling adults (mean ± SD: age=78.1 ± 5.4, 64.1% women, 77.6% white). MEASUREMENTS Baseline functional performance was determined by the SPPB measuring balance, gait speed, and 5 repeated chair stands. Fall history (past year) and efficacy in performing 10 daily activities without falling were assessed. Falls were assessed using a daily calendar over 4 years. Injurious falls were defined by fractures, sprains, dislocations, pulled or torn muscles, ligaments, or tendons or by seeking medical attention. RESULTS Poorest chair stand performance was associated with greater hazard of injurious falls compared to all other groups (HR [95% CI]: 1.96 [1.18–3.26], 1.65 [1.07–2.55], and 1.60 [1.03–2.48] for ≥16.7s vs. 13.7–16.6s, 11.2–13.6s, and <11.2s). SPPB did not predict injurious falls. Fall history predicted injurious falls (HR [95% CI]: 1.82 [1.39–2.39]); falls efficacy did not. Fall history and a slow chair stand (<16.7s) compounded 2-year cumulative incidence of an injurious fall (0.46, [0.34–0.58]) compared to positive fall history (0.29, [0.25–0.34]) or a slow chair stand alone (0.21, [0.13–0.30]). CONCLUSION An easily administered chair stand test may be sufficient for evaluating performance as part of a risk stratification strategy for injurious falls. PMID:25688606
ERIC Educational Resources Information Center
Rosen, Joshua B.; Olson, Mark H.; Kelly, Marianne
2012-01-01
Objective: The authors examined the impact of a collegiate-based emergency medical service (CBEMS) on the frequency of emergency department (ED) transports. Participants: Students transported to the ED for acute alcohol intoxication during the Fall 2008 and the Fall 2009 semesters (N = 50). Methods: The frequency of students receiving…
ERIC Educational Resources Information Center
Lee, Den-Ching A.; Pritchard, Elizabeth; McDermott, Fiona; Haines, Terry P.
2014-01-01
Objectives: To assess the effectiveness of patient education in reducing falls, promoting behavioural change and the uptake of prevention activities in older adults during and after hospitalization. Design: Systematic review and meta-analysis. Methods: A systematic search of five health science databases was performed up to November 2012. Studies…
This study focuses on three objectives: 1) to determine the feasibility of using a falling-film slurry photocatalytic reactor for the degradation of MTBE in water, 2) to assess the feasibility of MTBE photo-oxidation on TiO2 at low initial MTBE concentrations (<10 mg/L), and 3) t...
Forage radish winter cover crop suppresses winter annual weeds in fall and before corn planting
USDA-ARS?s Scientific Manuscript database
Forage radish (Raphanus sativus L. var. longipinnatus) is a new winter cover crop in the Mid-Atlantic region. The objective of this project was to characterize the repeatability, amount, and duration of weed suppression during and after a fall-planted forage radish cover crop and to quantify the sub...
Video analysis of falls experienced by paediatric iceskaters and roller/inline skaters
Knox, C L; Comstock, R D
2006-01-01
Objectives To evaluate differences in the way iceskaters and roller/inline skaters fall. Methods Children's falls related to skating were videotaped and categorised based on type of skating activity, child's estimated age, direction of fall, whether the child attempted to break the fall, and whether the head struck the skating surface. Results In total, 216 iceskating and 201 roller/inline skating falls were captured on videotape. In both iceskating and roller/inline skating, the majority of falls were forward in direction. The skaters attempted to break the falls with their arms or hands in over 90% of falls in both iceskating (93.1%) and roller/inline skating (94.5%). A greater proportion of falls in iceskating resulted in the head striking the skating surface (13.0%) than did those in roller/inline skating (3.0%) (odds ratio = 4.8; 95% confidence interval 1.9 to 13.3; p<0.001). Conclusions This study found that paediatric iceskaters and roller/inline skaters fall similarly and that both types of skaters try to break their falls with their arms or hands; however, because iceskating takes place on a low friction surface, attempts to break falls with the arms or hands are often unsuccessful, leading to head and face injuries. The development of a new type of protective gear, a wrist guard with a non‐slip palm, should stop iceskaters from striking the head, protect against upper extremity fractures, and unlike a bulky helmet, should not discourage children from skating. PMID:16505087
Jørgensen, Vivien; Roaldsen, Kirsti Skavberg
2016-01-01
Objective: Explore and describe experiences and perceptions of falls, risk of falling, and fall-related consequences in individuals with incomplete spinal cord injury (SCI) who are still walking. Design: A qualitative interview study applying interpretive content analysis with an inductive approach. Setting: Specialized rehabilitation hospital. Subjects: A purposeful sample of 15 individuals (10 men), 23 to 78 years old, 2-34 years post injury with chronic incomplete traumatic SCI, and walking ⩾75% of time for mobility needs. Methods: Individual, semi-structured face-to-face interviews were recorded, condensed, and coded to find themes and subthemes. Results: One overarching theme was revealed: “Falling challenges identity and self-image as normal” which comprised two main themes “Walking with incomplete SCI involves minimizing fall risk and fall-related concerns without compromising identity as normal” and “Walking with incomplete SCI implies willingness to increase fall risk in order to maintain identity as normal”. Informants were aware of their increased fall risk and took precautions, but willingly exposed themselves to risky situations when important to self-identity. All informants expressed some conditional fall-related concerns, and a few experienced concerns limiting activity and participation. Conclusion: Ambulatory individuals with incomplete SCI considered falls to be a part of life. However, falls interfered with the informants’ identities and self-images as normal, healthy, and well-functioning. A few expressed dysfunctional concerns about falling, and interventions should target these. PMID:27170274
NASA Astrophysics Data System (ADS)
Khiri, Fouad; Ibhi, Abderrahmane; Saint-Gerant, Thierry; Medjkane, Mohand; Ouknine, Lahcen
2017-10-01
The study of meteorites provides insight into the earliest history of our solar system. From 1800, about the year meteorites were first recognized as objects falling from the sky, until December 2014, 158 observed meteorite falls were recorded in Africa. Their collected mass ranges from 1.4 g to 175 kg with the 1-10 kg cases predominant. The average rate of African falls is low with only one fall recovery per 1.35-year time interval (or 0.023 per year per million km2). This African collection is dominated by ordinary chondrites (78%) just like in the worldwide falls. The seventeen achondrites include three Martian meteorite falls (Nakhla of Egypt, Tissint of Morocco and Zagami of Nigeria). Observed Iron meteorite falls are relatively rare and represent only 5%. The falls' rate in Africa is variable in time and in space. The number of falls continues to grow since 1860, 80% of which were recovered during the period between 1910 and 2014. Most of these documented meteorite falls have been recovered from North-Western Africa, Eastern Africa and Southern Africa. They are concentrated in countries which have a large surface area and a large population with a uniform distribution. Other factors are also favorable for observing and collecting meteorite falls across the African territory, such as: a genuine meteorite education, a semi-arid to arid climate (clear sky throughout the year most of the time), croplands or sparse grasslands and possible access to the fall location with a low percentage of forest cover and dense road network.
Two-year trajectory of fall risk in people with Parkinson’s disease: a latent class analysis
Paul, Serene S; Thackeray, Anne; Duncan, Ryan P; Cavanaugh, James T; Ellis, Theresa D; Earhart, Gammon M; Ford, Matthew P; Foreman, K Bo; Dibble, Leland E
2015-01-01
Objective To examine fall risk trajectories occurring naturally in a sample of individuals with early to middle stage Parkinson’s disease (PD). Design Latent class analysis, specifically growth mixture modeling (GMM) of longitudinal fall risk trajectories. Setting Not applicable. Participants 230 community-dwelling PD participants of a longitudinal cohort study who attended at least two of five assessments over a two year period. Interventions Not applicable. Main Outcome Measures Fall risk trajectory (low, medium or high risk) and stability of fall risk trajectory (stable or fluctuating). Fall risk was determined at 6-monthly intervals using a simple clinical tool based on fall history, freezing of gait, and gait speed. Results The GMM optimally grouped participants into three fall risk trajectories that closely mirrored baseline fall risk status (p=.001). The high fall risk trajectory was most common (42.6%) and included participants with longer and more severe disease and with higher postural instability and gait disability (PIGD) scores than the low and medium risk trajectories (p<.001). Fluctuating fall risk (posterior probability <0.8 of belonging to any trajectory) was found in only 22.6% of the sample, most commonly among individuals who were transitioning to PIGD predominance. Conclusions Regardless of their baseline characteristics, most participants had clear and stable fall risk trajectories over two years. Further investigation is required to determine whether interventions to improve gait and balance may improve fall risk trajectories in people with PD. PMID:26606871
High Temperature Falling Particle Receiver (2012 - 2016) - Final DOE Report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ho, Clifford K.
The objective of this work was to advance falling particle receiver designs for concentrating solar power applications that will enable higher temperatures (>700 °C) and greater power-cycle efficiencies (≥50% thermal-to-electric). Modeling, design, and testing of components in Phases 1 and 2 led to the successful on-sun demonstration in Phase 3 of the world’s first continuously recirculating high-temperature 1 MW t falling particle receiver that achieved >700 °C particle outlet temperatures at mass flow rates ranging from 1 – 7 kg/s.
Combined optical sizing and acoustical characterization of single freely-floating microbubbles
NASA Astrophysics Data System (ADS)
Luan, Ying; Renaud, Guillaume; Raymond, Jason L.; Segers, Tim; Lajoinie, Guillaume; Beurskens, Robert; Mastik, Frits; Kokhuis, Tom J. A.; van der Steen, Antonius F. W.; Versluis, Michel; de Jong, Nico
2016-12-01
In this study we present a combined optical sizing and acoustical characterization technique for the study of the dynamics of single freely-floating ultrasound contrast agent microbubbles exposed to long burst ultrasound excitations up to the milliseconds range. A co-axial flow device was used to position individual microbubbles on a streamline within the confocal region of three ultrasound transducers and a high-resolution microscope objective. Bright-field images of microbubbles passing through the confocal region were captured using a high-speed camera synchronized to the acoustical data acquisition to assess the microbubble response to a 1-MHz ultrasound burst. Nonlinear bubble vibrations were identified at a driving pressure as low as 50 kPa. The results demonstrate good agreement with numerical simulations based on the shell-buckling model proposed by Marmottant et al. [J. Acoust. Soc. Am. 118, 3499-3505 (2005)]. The system demonstrates the potential for a high-throughput in vitro characterization of individual microbubbles.
NCTM of liquids at high temperatures using polarization techniques
NASA Technical Reports Server (NTRS)
Krishnan, Shankar; Weber, J. K. Richard; Nordine, Paul C.; Schiffman, Robert A.
1990-01-01
Temperature measurement and control is extremely important in any materials processing application. However, conventional techniques for non-contact temperature measurement (mainly optical pyrometry) are very uncertain because of unknown or varying surface emittance. Optical properties like other properties change during processing. A dynamic, in-situ measurement of optical properties including the emittance is required. Intersonics is developing new technologies using polarized laser light scattering to determine surface emittance of freely radiating bodies concurrent with conventional optical pyrometry. These are sufficient to determine the true surface temperature of the target. Intersonics is currently developing a system called DAPP, the Division of Amplitude Polarimetric Pyrometer, that uses polarization information to measure the true thermodynamic temperature of freely radiating objects. This instrument has potential use in materials processing applications in ground and space based equipment. Results of thermophysical and thermodynamic measurements using laser reflection as a temperature measuring tool are presented. The impact of these techniques on thermophysical property measurements at high temperature is discussed.
Automatic Camera Calibration for Cultural Heritage Applications Using Unstructured Planar Objects
NASA Astrophysics Data System (ADS)
Adam, K.; Kalisperakis, I.; Grammatikopoulos, L.; Karras, G.; Petsa, E.
2013-07-01
As a rule, image-based documentation of cultural heritage relies today on ordinary digital cameras and commercial software. As such projects often involve researchers not familiar with photogrammetry, the question of camera calibration is important. Freely available open-source user-friendly software for automatic camera calibration, often based on simple 2D chess-board patterns, are an answer to the demand for simplicity and automation. However, such tools cannot respond to all requirements met in cultural heritage conservation regarding possible imaging distances and focal lengths. Here we investigate the practical possibility of camera calibration from unknown planar objects, i.e. any planar surface with adequate texture; we have focused on the example of urban walls covered with graffiti. Images are connected pair-wise with inter-image homographies, which are estimated automatically through a RANSAC-based approach after extracting and matching interest points with the SIFT operator. All valid points are identified on all images on which they appear. Provided that the image set includes a "fronto-parallel" view, inter-image homographies with this image are regarded as emulations of image-to-world homographies and allow computing initial estimates for the interior and exterior orientation elements. Following this initialization step, the estimates are introduced into a final self-calibrating bundle adjustment. Measures are taken to discard unsuitable images and verify object planarity. Results from practical experimentation indicate that this method may produce satisfactory results. The authors intend to incorporate the described approach into their freely available user-friendly software tool, which relies on chess-boards, to assist non-experts in their projects with image-based approaches.
[Evaluation of a simple screening tool for ambulant fall prevention].
Knobe, M; Rasche, P; Rentemeister, L; Bliemel, C; Bücking, B; Bollheimer, L C; Pape, H-C
2018-02-02
An individual's risk of falling is generally difficult to detect and it is likely to be underestimated. Thus, preventive measures are challenging and they demand sufficient integration and implementation into aftercare and outpatient management. The Aachen Falls Prevention Scale (AFPS) is a quick and easy tool for patient-driven fall risk assessment. Older adults' risk of falling is identified in a suitable manner and they then have the opportunity to independently assess and monitor their risk of falling. The aim of the current study was to evaluate the AFPS as a simple screening tool in geriatric trauma patients via the identification of influencing factors, e.g. objective or subjective fall risk, fear of falling (FOF) and demographic data. In this context, we investigated older adults' willingness to take part in special activities concerning fall prevention. Retrospectively, all patients over 70 years of age who received in-hospital fracture treatment between July 2014 and April 2016 were analyzed at a level I trauma center. After identification of 884 patients, participants completed a short questionnaire (47 questions, yes/no, Likert scale) comprising the AFPS. A history of falls in the past year was considered an indicator of a balance disorder. In addition, ambulant patients were invited to participate between July and August 2016. In total, 201 patients (mean 80.4 years, range 63-97 years) performed a self-assessment based on the AFPS. After steps 1 and 2 of the AFPS had been completed, 95 (47%) participants rated their subjective risk of falling as high (more than 5 points). Of the participants 84 (42%) were objectively classified as "fallers" with significant effects on their AFPS evaluation and rating of their subjective risk of falling. Furthermore, 67% of the participants identified a general practitioner as their main contact person, and 43% of the respondents viewed the AFPS as a beneficial screening tool in fall risk evaluation (8% negative attitudes). Only 12% of the participants could imagine using the AFPS app version as a feasible option. It would be advantageous to pretest at-risk individuals in their environment using a simple self-assessment approach, with the main purpose of identifying potential balance problems. With this approach, cost savings in the healthcare system are possible, combined with a higher health-related quality of life in the geriatric population.
Sensor-derived physical activity parameters can predict future falls in people with dementia
Schwenk, Michael; Hauer, Klaus; Zieschang, Tania; Englert, Stefan; Mohler, Jane; Najafi, Bijan
2014-01-01
Background There is a need for simple clinical tools that can objectively assess fall risk in people with dementia. Wearable sensors seem to have potential for fall prediction, however, there has been limited work performed in this important area. Objective To explore the validity of sensor-derived physical activity (PA) parameters for predicting future falls in people with dementia. To compare sensor-based fall risk assessment with conventional fall risk measures. Methods A cohort study of people with confirmed dementia discharged from a geriatric rehabilitation ward. PA was quantified using 24-hour motion-sensor monitoring at the beginning of the study. PA parameters (percentage of walking, standing, sitting, lying; duration of single walking, standing, and sitting bouts) were extracted using specific algorithms. Conventional assessment included performance-based tests (Timed-up-and-go test, Performance-Oriented-Mobility-Assessment, 5-chair stand) and questionnaires (cognition, ADL-status, fear of falling, depression, previous faller). Outcome measures were fallers (at least one fall in the 3-month follow-up period) versus non-fallers. Results Seventy-seven people were included in the study (age 81.8 ± 6.3; community dwelling 88%, institutionalized 12%). Surprisingly, fallers and non-fallers did not differ on any conventional assessment (p= 0.069–0.991), except for ‘previous faller’ (p= 0.006). Interestingly, several PA parameters discriminated between groups. The ‘walking bouts average duration’, ‘longest walking bout duration’ and ‘walking bouts duration variability’ were lower in fallers, compared to non-fallers (p= 0.008–0.027). The ‘standing bouts average duration’ was higher in fallers (p= 0.050). Two variables, ‘walking bouts average duration’ [odds ratio (OR) 0.79, p= 0.012] and ‘previous faller’ [OR 4.44, p= 0.007] were identified as independent predictors for falls. The OR for a ‘walking bouts average duration’ of less than 15 seconds for predicting fallers was 6.30 (p= 0.020). Combining ‘walking bouts average duration’ and ‘previous faller’ improved fall prediction [OR 7.71, p< 0.001, sensitivity/specificity 72%/76%]. Discussion Results demonstrate that sensor-derived PA parameters are independent predictors of fall risk and may have higher diagnostic accuracy in persons with dementia compared to conventional fall risk measures. Our findings highlight the potential of telemonitoring technology for estimating fall risk. Results should be confirmed in a larger study and by measuring PA over a longer time period. PMID:25171300
Prevalence of and factors associated with head impact during falls in older adults in long-term care
Schonnop, Rebecca; Yang, Yijian; Feldman, Fabio; Robinson, Erin; Loughin, Marie; Robinovitch, Stephen N.
2013-01-01
Background: Falls cause more than 60% of head injuries in older adults. Lack of objective evidence on the circumstances of these events is a barrier to prevention. We analyzed video footage to determine the frequency of and risk factors for head impact during falls in older adults in 2 long-term care facilities. Methods: Over 39 months, we captured on video 227 falls involving 133 residents. We used a validated questionnaire to analyze the mechanisms of each fall. We then examined whether the probability for head impact was associated with upper-limb protective responses (hand impact) and fall direction. Results: Head impact occurred in 37% of falls, usually onto a vinyl or linoleum floor. Hand impact occurred in 74% of falls but had no significant effect on the probability of head impact (p = 0.3). An increased probability of head impact was associated with a forward initial fall direction, compared with backward falls (odds ratio [OR] 2.7, 95% confidence interval [CI] 1.3–5.9) or sideways falls (OR 2.8, 95% CI 1.2–6.3). In 36% of sideways falls, residents rotated to land backwards, which reduced the probability of head impact (OR 0.2, 95% CI 0.04–0.8). Interpretation: Head impact was common in observed falls in older adults living in long-term care facilities, particularly in forward falls. Backward rotation during descent appeared to be protective, but hand impact was not. Attention to upper-limb strength and teaching rotational falling techniques (as in martial arts training) may reduce fall-related head injuries in older adults. PMID:24101612
An evaluation of hospital discharge records as a tool for serious work related injury surveillance
Alamgir, H; Koehoorn, M; Ostry, A; Tompa, E; Demers, P
2006-01-01
Objectives To identify and describe work related serious injuries among sawmill workers in British Columbia, Canada using hospital discharge records, and compare the agreement and capturing patterns of the work related indicators available in the hospital discharge records. Methods Hospital discharge records were extracted from 1989 to 1998 for a cohort of sawmill workers. Work related injuries were identified from these records using International Classification of Disease (ICD‐9) external cause of injury codes, which have a fifth digit, and sometimes a fourth digit, indicating place of occurrence, and the responsibility of payment schedule, which identifies workers' compensation as being responsible for payment. Results The most frequent causes of work related hospitalisations were falls, machinery related, overexertion, struck against, cutting or piercing, and struck by falling objects. Almost all cases of machinery related, struck by falling object, and caught in or between injuries were found to be work related. Overall, there was good agreement between the two indicators (ICD‐9 code and payment schedule) for identifying work relatedness of injury hospitalisations (kappa = 0.75, p < 0.01). There was better concordance between them for injuries, such as struck against, drowning/suffocation/foreign body, fire/flame/natural/environmental, and explosions/firearms/hot substance/electric current/radiation, and poor concordance for injuries, such as machinery related, struck by falling object, overexertion, cutting or piercing, and caught in or between. Conclusions Hospital discharge records are collected for administrative reasons, and thus are readily available. Depending on the coding reliability and validity, hospital discharge records represent an alternative and independent source of information for serious work related injuries. The study findings support the use of hospital discharge records as a potential surveillance system for such injuries. PMID:16556751
Comparison of different strategies of referral to a fall clinic: how to achieve an optimal casemix?
Schoon, Y; Hoogsteen-Ossewaarde, M E; Scheffer, A C; Van Rooij, F J M; Rikkert, M G M Olde; De Rooij, S E
2011-02-01
OBJECTIVE To study the potential differences in patient characteristics between two referral methods to a fall clinic, specifically: case-finding of patients admitted to an emergency department because of a fall, compared to direct referral to the fall clinic via the general practitioner. Cross-sectional study. Fall clinics in two university teaching hospitals in the Netherlands. Three hundred community-dwelling older people aged 65 years or over currently attending the fall clinics in Nijmegen (Group 1, n=154) and in Amsterdam (Group 2, n=146). Patients were referred by a general practitioner (Group 1) or were selected using the Carefall Triage Instrument (CTI) after visiting the emergency department (Group 2). In all patients, modifiable risk factors for recurrent falls were assessed. Group 1 had less modifiable risk factors for falling (a mean of 4 (SD 1.6) vs. a mean of 5 (SD 1.5) in Group 2, p < 0.001). Compared to Group 2, Group 1 had more prevalent " recurrent falling (≥ 2 falls)" (p=0.001) and "assisted living in homes for the aged" (p=0.037). "Fear of falling", "mobility and balance problems", "home hazards" and "osteoporosis" were significantly less prevalent in Group 1. This study suggests that patients referred to a multidisciplinary fall prevention clinic by their general practitioner have a different risk profile than those selected by case finding using the CTI. These differences have consequences for the reach of secondary care for fall-preventive interventions and will probably influence the effectiveness and efficiency of a fall prevention program.
Tiedemann, Anne; Paul, Serene; Ramsay, Elisabeth; O'Rourke, Sandra D; Chamberlain, Kathryn; Kirkham, Catherine; Merom, Dafna; Fairhall, Nicola; Oliveira, Juliana S; Hassett, Leanne; Sherrington, Catherine
2015-05-09
Physical inactivity and falls in older people are important public health problems. Health conditions that could be ameliorated with physical activity are particularly common in older people. One in three people aged 65 years and over fall at least once annually, often resulting in significant injuries and ongoing disability. These problems need to be urgently addressed as the population proportion of older people is rapidly rising. This trial aims to establish the impact of a combined physical activity and fall prevention intervention compared to an advice brochure on objectively measured physical activity participation and mobility-related goal attainment among people aged 60+. A randomised controlled trial involving 130 consenting community-dwelling older people will be conducted. Participants will be individually randomised to a control group (n = 65) and receive a fall prevention brochure, or to an intervention group (n = 65) and receive the brochure plus physical activity promotion and fall prevention intervention enhanced with health coaching and a pedometer. Primary outcomes will be objectively measured physical activity and mobility-related goal attainment, measured at both six and 12 months post randomisation. Secondary outcomes will include: falls, the proportion of people meeting the physical activity guidelines, quality of life, fear of falling, mood, and mobility limitation. Barriers and enablers to physical activity participation will be measured 6 months after randomisation. General linear models will be used to assess the effect of group allocation on the continuously-scored primary and secondary outcome measures, after adjusting for baseline scores. Between-group differences in goal attainment (primary outcome) will be analysed with ordinal regression. The number of falls per person-year will be analysed using negative binomial regression models to estimate the between-group difference in fall rates after one year (secondary outcome). Modified Poisson regression models will compare groups on dichotomous outcome measures. Analyses will be pre-planned, conducted while masked to group allocation and will use an intention-to-treat approach. This trial will address a key gap in evidence regarding physical activity and fall prevention for older people and will evaluate a program that could be directly implemented within Australian health services. ACTRN12614000016639, 7/01/2014.
Zecevic, Aleksandra A; Salmoni, Alan W; Lewko, John H; Vandervoort, Anthoney A; Speechley, Mark
2009-10-01
As a highly heterogeneous group, seniors live in complex environments influenced by multiple physical and social structures that affect their safety. Until now, the major approach to falls research has been person centered. However, in industrial settings, the individuals involved in an accident are seen as the inheritors of system defects. The objective of the present study was to investigate safety deficiencies that contributed to falls in community-dwelling seniors using a systems approach. The investigations were conducted using the Seniors Falls Investigation Methodology (SFIM), an adapted version of a method used to examine transportation accidents, such as airplane crashes. Fifteen seniors, who experienced a fall or near fall, participated in multiple case studies. A cross-case synthesis was used to summarize findings and identify common patterns of causes and safety deficiencies. Falls and near falls are a result of latent unsafe conditions, and unsafe acts and decisions combined in a diverse set of circumstances. If not identified and removed, these unsafe conditions can cause falls for other seniors. This study provided compelling evidence that causes of falling are systemic and develop over time. It demonstrated that the systems approach is needed to expand the focus from the individual to multilayered organizational and supervisory causes. The SFIM demonstrated capability to identify causes of falls that will allow better prevention and management programs, hence advancing seniors' safety. SFIM shows great potential for implementation in organized settings, such as hospitals and long-term care homes.
Fall scenarios In causing older women's hip fractures.
Hägvide, Mona-Lisa; Larsson, Tore J; Borell, Lena
2013-01-01
Falls and fall-related injuries among older women constitute a major public health problem with huge costs for the society and personal suffering. The aim of this study was to describe and illustrate how a number of circumstances, conceptualized as a scenario, that were related to the individual, the environment, and the ongoing occupation contributed to a fall that led to a hip fracture among women. The sample included 48 women over 55 years old. Interviews were conducted during home visits and the analysis provided a descriptive picture of circumstances in the shape of a scenario related to the risk of falling. A number of scenarios were developed based on the data and named to provide an understanding of the interplay between the individual, the environment, and the ongoing occupation at the time of the fall. By applying the concept of a scenario, occupational therapists can increase the awareness of fall risks among older people, and are relevant also for interior designers, architects, and town planners to consider when designing the local environment as well as furniture and other objects.
ERIC Educational Resources Information Center
Mohazzabi, Pirooz
2010-01-01
When an object is immersed in a liquid and released, it may sink to the bottom or rise to the surface and float. If the object's density is greater than that of the liquid, it sinks. If the object's density is less than the density of the liquid, it floats. In the special case when the object's density matches the density of the liquid, it will…
Pattern of childhood falls in a low-income setting: a cross-sectional study in Dar es Salaam.
Kamala, Benjamin; Wilson, Michael L; Hasselberg, Marie
2011-12-01
The objective was to determine patterns and circumstances of childhood falls in a low-income setting in Dar es Salaam, Tanzania. This cross sectional study is based on a household survey conducted in July 2009. A total of 3927 children up to age 18 from 1928 households in 15 sampled wards were surveyed through a structured questionnaire. The current study includes information regarding fall occurrence, socio-demographic and economic factors. Data were analysed using chi-square, t-test and logistic regression. Male children had 42% higher odds of falls compared to females, and rural residents had more than two times higher odds compared to urban residents. Falls occurred three times more among age group 1-4 and two times more among age group 5-9 compared to those between 15 and 18 years. Most falls occurred outdoors (62%) while playing (51%) with boys being over-represented. Females and children aged 1-4 years fell more from stairs whereas most infants fell from furniture. Male gender, younger age groups and rural residence were significant factors for fall injuries. The circumstances in which these falls occur also differ significantly. Intervention efforts should emphasise these patterns.
Terminal velocity of a shuttlecock in vertical fall
NASA Astrophysics Data System (ADS)
Peastrel, Mark; Lynch, Rosemary; Armenti, Angelo
1980-07-01
We have performed a straightforward vertical fall experiment for a case where the effects of air resistance are important and directly measurable. Using a commonly available badminton shuttlecock, a tape measure, and a millisecond timer, the times required for the shuttlecock to fall given distances (up to almost ten meters) were accurately measured. The experiment was performed in an open stairwell. The experimental data was compared to the predictions of several models. The best fit was obtained with the model which assumes a resistive force quadratic in the instantaneous speed of the falling object. This model was fitted to the experimental data enabling us to predict the terminal velocity of the shuttlecock (6.80 m/sec). The results indicate that, starting from rest, the vertically falling shuttlecock achieves 99% of its terminal velocity in 1.84 sec, after falling 9.2 m. The relative ease in collecting the data, as well as the excellent agreement with theory, make this an ideal experiment for use in physics courses at a variety of levels.
Workplace slip, trip and fall injuries and obesity.
Koepp, Gabriel A; Snedden, Bradley J; Levine, James A
2015-01-01
The objective of this study was to examine the relationship between slip, trip and fall injuries and obesity in a population of workers at the Idaho National Laboratory (INL) in Idaho Falls, Idaho. INL is an applied engineering facility dedicated to supporting the US Department of Energy's mission. An analysis was performed on injuries reported to the INL Medical Clinic to determine whether obesity was related to an increase in slip, trip and fall injuries. Records were analysed that spanned a 6-year period (2005-2010), and included 8581 employees (mean age, 47 ± 11 years and body mass index [BMI], 29 ± 5 kg/m(2); 34% obesity rate). Of the 189 people who reported slip, trip and fall injuries (mean age, 48 ± 11 years), 51% were obese (P < 0.001 compared with uninjured employees), and their mean BMI was 31 ± 6 kg/m(2) (P < 0.001). Obesity in this population was associated with a greater rate of slip, trip and fall injuries.
Balance Training Reduces Falls Risk in Older Individuals With Type 2 Diabetes
Morrison, Steven; Colberg, Sheri R.; Mariano, Mira; Parson, Henri K.; Vinik, Arthur I.
2010-01-01
OBJECTIVE This study assessed the effects of balance/strength training on falls risk and posture in older individuals with type 2 diabetes. RESEARCH DESIGN AND METHODS Sixteen individuals with type 2 diabetes and 21 age-matched control subjects (aged 50–75 years) participated. Postural stability and falls risk was assessed before and after a 6-week exercise program. RESULTS Diabetic individuals had significantly higher falls risk score compared with control subjects. The diabetic group also exhibited evidence of mild-to-moderate neuropathy, slower reaction times, and increased postural sway. Following exercise, the diabetic group showed significant improvements in leg strength, faster reaction times, decreased sway, and, consequently, reduced falls risk. CONCLUSIONS Older individuals with diabetes had impaired balance, slower reactions, and consequently a higher falls risk than age-matched control subjects. However, all these variables improved after resistance/balance training. Together these results demonstrate that structured exercise has wide-spread positive effects on physiological function for older individuals with type 2 diabetes. PMID:20097781
ERIC Educational Resources Information Center
Wallace, Deshira D.; Boynton, Marcella H.; Lytle, Leslie A.
2017-01-01
Objective: This study explored the association of stress and depression with a multidimensional sleep problems construct in a sample of 2-year college students. Participants: The sample consisted of 440 students enrolled in 2-year study from Fall 2011 to Fall 2013. Methods: Participants in an obesity prevention study completed surveys assessing…
DOT National Transportation Integrated Search
1997-06-18
This paper is the third in a series that together will comprise an Intelligent Transportation System Study (ITS) for the Buffalo/Niagara Falls region. In this document, the problems identified in Working Paper #1 are critically reviewed to develop go...
Equivalent Fall Risk in Elderly Patients on Hemodialysis and Peritoneal Dialysis.
Farragher, Janine; Rajan, Tasleem; Chiu, Ernest; Ulutas, Ozkan; Tomlinson, George; Cook, Wendy L; Jassal, Sarbjit V
2016-01-01
♦ Accidental falls are common in the hemodialysis (HD) population. The high fall rate has been attributed to a combination of aging, kidney disease-related morbidity, and HD treatment-related hazards. We hypothesized that patients maintained on peritoneal dialysis (PD) would have fewer falls than those on chronic HD. The objective of this study was to compare the falls risk between cohorts of elderly patients maintained on HD and PD, using prospective data from a large academic dialysis facility. ♦ Patients aged 65 years or over on chronic in-hospital HD and PD at the University Health Network were recruited. Patients were followed biweekly, and falls occurring within the first year recorded. Fall risk between the 2 groups was compared using both crude and adjusted Poisson lognormal random effects modeling. ♦ Out of 258 potential patients, 236 were recruited, assessed at baseline, and followed biweekly for falls. Of 74 PD patients, 40 (54%) experienced 86 falls while 76 out of 162 (47%) HD patients experienced a total of 305 falls (crude fall rate 1.25 vs 1.60 respectively, odds ratio [OR] falls in PD patients 0.78, 95% confidence interval [CI] 0.61 - 0.92, p = 0.04). After adjustment for differences in comorbidity, number of medications, and other demographic differences, PD patients were no less likely to experience accidental falls than HD patients (OR 1.63, 95% CI 0.88 - 3.04, p = 0.1). ♦ We conclude that accidental falls are equally common in the PD population and the HD population. These data argue against post-HD hypotension as the sole contributor to the high fall risk in the dialysis population. Copyright © 2016 International Society for Peritoneal Dialysis.
Legrand, Helen; Pihlsgård, Mats; Nordell, Eva; Elmståhl, Sölve
2015-08-01
Few studies on fall risk factors use long-recommended methods for analysis of recurrent events. Previous falls are the biggest risk factor for future falls, but few fall studies focus on the youngest-old. This study's objective was to apply Cox regression for recurrent events to identify factors associated with injurious falls in the youngest-old. Participants were community-dwelling residents of southern Sweden (n = 1,133), aged 59-67 at baseline (median 61.2), from the youngest cohorts of the larger Good Aging in Skåne (GÅS) study. Exposure variable data were collected from baseline study visits and medical records. Injurious falls, defined as emergency, inpatient, or specialist visits associated with ICD-10 fall codes during the follow-up period (2001-2011), were gathered from national and regional registries. Analysis was conducted using time to event Cox Regression for recurrent events. A majority (77.1 %) of injurious falls caused serious injuries such as fractures and open wounds. Exposure to nervous system medications [hazard ratio (HR) 1.40, 95 % confidence interval (CI) 1.03-1.89], central nervous system disease (HR 1.79, CI 1.18-2.70), and previous injurious fall(s) (HR 2.00, CI 1.50-2.68) were associated with increased hazard of injurious fall. Regression for recurrent events is feasible with typical falls' study data. The association of certain exposures with increased hazard of injurious falls begins earlier than previously studied. Different patterns of risk factors by age can provide insight into the progression of frailty. Tailored fall prevention screening and intervention may be of value in populations younger than those traditionally screened.
Lee, Justin Yusen; Holbrook, Anne
2017-02-20
Despite limited evidence of effectiveness, withdrawal (discontinuation or dose reduction) of high risk medications known as "fall-risk increasing drugs" (FRIDs) is typically conducted as a fall prevention strategy based on presumptive benefit. Our objective is to determine the efficacy of fall-risk increasing drugs (FRIDs) withdrawal on the prevention of falls and fall-related complications. We will search for all published and unpublished randomized controlled trials evaluating the effect of FRID withdrawal compared to usual care on the rate of falls, incidence of falls, fall-related injuries, fall-related fractures, fall-related hospitalizations, or adverse effects related to the intervention in adults aged 65 years or older. Electronic database searches will be conducted in MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), and CINAHL. A grey literature search will be conducted including clinical trial registries and conference proceedings and abstracts. Two reviewers will independently perform in duplicate citation screening, full-text review, data abstraction, and risk of bias assessment. Conflicts will be resolved through team discussion or by a third reviewer if no consensus can be reached. The Grades of Recommendation, Assessment, Development and Evaluation (GRADE) criteria will be used to independently rate overall confidence in effect estimates for each outcome. Results will be synthesized descriptively, and a random effects meta-analysis will be conducted for each outcome if studies are deemed similar methodologically, clinically, and statistically. We will attempt to determine whether a FRID withdrawal strategy alone is effective at preventing falls in older adults. Our results will be used to optimize and focus fall prevention strategies and initiatives internationally with a goal of improving the health of older adults. PROSPERO CRD42016040203.
Mobility assessment: Sensitivity and specificity of measurement sets in older adults
Panzer, Victoria P.; Wakefield, Dorothy B.; Hall, Charles B.; Wolfson, Leslie I.
2011-01-01
Objective To identify quantitative measurement variables that characterize mobility in older adults, meet reliability and validity criteria, distinguish fall-risk and predict future falls. Design Observational study with 1-year weekly falls follow-up Setting Mobility laboratory Participants Community-dwelling volunteers (n=74; 65–94 years old) categorized at entry as 27 ‘Non-fallers’ or 47 ‘Fallers’ by Medicare criteria (1 injury fall or >1 non-injury falls in the previous year). Interventions None Outcome Measures Test-retest and within-subject reliability, criterion and concurrent validity; predictive ability indicated by observed sensitivity and specificity to entry fall-risk group (Falls-status), Tinetti Performance Oriented Mobility Assessment (POMA), Computerized Dynamic Posturography Sensory Organization Test (SOT) and subsequent falls reported weekly. Results Measurement variables were selected that met reliability (ICC > 0.6) and/or discrimination (p<.01) criteria (Clinical variables- Turn- steps, time, Gait- velocity, Step-in-tub-time, and Downstairs- time; Force plate variables- Quiet standing Romberg ratio sway-area, Maximal lean- anterior-posterior excursion, Sit-to-stand medial-lateral excursion and sway-area). Sets were created (3 clinical, 2 force plate) utilizing combinations of variables appropriate for older adults with different functional activity levels and composite scores were calculated. Scores identified entry Falls-status and concurred with POMA and SOT. The Full clinical set (5 measurement variables) produced sensitivity/specificity (.80/.74) to Falls-status. Composite scores were sensitive and specific in predicting subsequent injury falls and multiple falls compared to Falls-status, POMA or SOT. Conclusions Sets of quantitative measurement variables obtained with this mobility battery provided sensitive prediction of future injury falls and screening for multiple subsequent falls using tasks that should be appropriate to diverse participants. PMID:21621667
Rice, Laura A; Ousley, Cherita; Sosnoff, Jacob J
2015-01-01
To systematically review peer-reviewed literature pertaining to risk factors, outcome measures and interventions managing fall risk in non-ambulatory adults. Twenty-one papers were selected for inclusion from databases including PubMed/Medline, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Cochrane Library, Scopus, Consumer Health Complete and Web of Science. Selected studies involved a description of fall related risk factors, outcomes to assess fall risk and intervention studies describing protocols to manage fall risk in non-ambulatory adults. Studies were selected by two reviewers and consultation provided by a third reviewer. The most frequently cited risk factors/characteristics associated with falls included: wheelchair related characteristics, transfer activities, impaired seated balance and environmental factors. The majority of the outcomes were found to evaluate seated postural control. One intervention study was identified describing a protocol targeting specific problems of individual participants. A global fall prevention program was not identified. Several risk factors associated with falls were identified and must be understood by clinicians to better serve their clients. To improve objective assessment, a comprehensive outcome assessment specific to non-ambulatory adults is needed. Finally, additional research is needed to examine the impact of structured protocols to manage fall risk in non-ambulatory adults. Falls are a common health concern for non-ambulatory adults. Risk factors commonly associated with falls include wheelchair related characteristics, transfer activities, impaired seated balance and environmental factors. Limited outcome measures are available to assess fall risk in non-ambulatory adults. Clinicians must be aware of the known risk factors and provide comprehensive education to their clients on the potential for falls. Additional research is needed to develop and evaluate protocols to clinically manage fall risk.
Foot Function, Foot Pain, and Falls in Older Adults: the Framingham Foot Study
Awale, Arunima; Hagedorn, Thomas J.; Dufour, Alyssa B.; Menz, Hylton B.; Casey, Virginia A.; Hannan, Marian T.
2017-01-01
Background Although foot pain has been linked to fall risk, contributions of pain severity, foot posture or foot function are unclear. These factors were examined in a cohort of older adults. Objective The purpose of this study was to examine the associations of foot pain, severity of foot pain and measures of foot posture and dynamic foot function with reported falls in a large, well-described cohort of older adults from the Framingham Foot Study. Methods Foot pain, posture and function were collected from Framingham Foot Study participants who were queried about falls over the past year (0, 1, 2+ falls). Logistic regression was used to calculate odds ratios (OR) and 95% confidence intervals (CI) for the relation of falls with foot pain, pain severity, foot posture, and foot function adjusting for covariates. Results Of 1375 participants, mean age was 69y; 57% were female; 21% reported foot pain (40% mild pain, 47% moderate, 13% severe pain). One-third reported falls in past year (1 fall: n=263, 2+ falls: n=152). Foot pain was associated with a 62% increased odds of recurrent falls. Those with moderate and severe foot pain showed increased odds of 2+ falls (OR=1.78, CI 1.06–2.99, and OR = 3.25, CI 1.65–7.48, respectively) compared to no foot pain. Foot function was not associated with falls. Compared to normal foot posture, those with planus foot posture had 78% higher odds of 2+ falls. Conclusion Higher odds of recurrent falls were observed in individuals with foot pain, especially severe foot pain, as well as individuals with planus foot posture, indicating that both foot pain and foot posture may play a role in increasing the risk of falls among older adults. PMID:28482340
Hoffmann, V S; Neumann, L; Golgert, S; von Renteln-Kruse, W
2015-12-01
Prevention of in-hospital falls contributes to improvement of patient safety. However, the identification of high-risk patients remains a challenge despite knowledge of fall-risk factors. Hence, objective was to prospectively validate the performance of the LUCAS (Longitudinal Urban Cohort Ageing Study) fall-risk screening, based on routine data (fall history, mobility, mental status) and applied by nurses. Observational study comparing two groups of patients who underwent different fall-risk screenings; the LUCAS screening (2010 - 2011) and the STRATIFY (St. Thomas's Risk Assessment Tool In Falling Elderly Inpatients) (2004 - 2006). Urban teaching hospital. Consecutively hospitalized patients (≥ 65 years old) were screened on admission; LUCAS n = 2,337, STRATIFY n = 4,735. The proportions of fallers were compared between the STRATIFY and the LUCAS time periods. The number of fallers expected was compared to that observed in the LUCAS time period. Standardized fall-incidence recording included case-note checks for unreported falls. Plausibility checks of fall-risk factors and logistic regression analysis for variable fall-risk factors were performed. The proportions of fallers during the two time periods were LUCAS n = 291/2,337 (12.5%) vs. STRATIFY n = 508/4,735 (10.7%). After adjustment for risk-factor prevalence, the proportion of fallers expected was 14.5% (334/2,337), the proportion observed was 12.5% (291/2,337) (p = 0.038). In-hospital fall prevention including systematic use of the LUCAS fall-risk screening reduced the proportion of fallers compared to that expected from the patients' fall-risk profile. Raw proportions of fallers are not suitable to evaluate fall prevention in hospital because of variable prevalence of patients' fall-risk factors over time. Continuous communication, education and training is needed to sustain in-hospital falls prevention.
Identification of fall risk factors in older adult emergency department patients.
Carpenter, Christopher R; Scheatzle, Mark D; D'Antonio, Joyce A; Ricci, Paul T; Coben, Jeffrey H
2009-03-01
Falls represent an increasingly frequent source of injury among older adults. Identification of fall risk factors in geriatric patients may permit the effective utilization of scarce preventative resources. The objective of this study was to identify independent risk factors associated with an increased 6-month fall risk in community-dwelling older adults discharged from the emergency department (ED). This was a prospective observational study with a convenience sampling of noninstitutionalized elders presenting to an urban teaching hospital ED who did not require hospital admission. Interviews were conducted to determine the presence of fall risk factors previously described in non-ED populations. Subjects were followed monthly for 6 months through postcard or telephone contact to identify subsequent falls. Univariate and Cox regression analysis were used to determine the association of risk factors with 6-month fall incidence. A total of 263 patients completed the survey, and 161 (61%) completed the entire 6 months of follow-up. Among the 263 enrolled, 39% reported a fall in the preceding year, including 15% with more than one fall and 22% with injurious falls. Among those completing the 6 months of follow-up, 14% reported at least one fall. Cox regression analysis identified four factors associated with falls during the 6-month follow-up: nonhealing foot sores (hazard ratio [HR] = 3.71, 95% confidence interval [CI] = 1.73 to 7.95), a prior fall history (HR = 2.62, 95% CI = 1.32 to 5.18), inability to cut one's own toenails (HR = 2.04, 95% CI = 1.04 to 4.01), and self-reported depression (HR = 1.72, 95% CI = 0.83 to 3.55). Falls, recurrent falls, and injurious falls in community-dwelling elder ED patients being evaluated for non-fall-related complaints occur at least as frequently as in previously described outpatient cohorts. Nonhealing foot sores, self-reported depression, not clipping one's own toenails, and previous falls are all associated with falls after ED discharge.
Identifying nursing home residents at risk for falling.
Kiely, D K; Kiel, D P; Burrows, A B; Lipsitz, L A
1998-05-01
To develop a fall risk model that can be used to identify prospectively nursing home residents at risk for falling. The secondary objective was to determine whether the nursing home environment independently influenced the development of falls. A prospective study involving 1 year of follow-up. Two hundred seventy-two nursing homes in the state of Washington. A total of 18,855 residents who had a baseline assessment in 1991 and a follow-up assessment within the subsequent year. Baseline Minimum Data Set items that could be potential risk factors for falling were considered as independent variables. The dependent variable was whether the resident fell as reported at the follow-up assessment. We estimated the extrinsic risk attributable to particular nursing home environments by calculating the annual fall rate in each nursing home and grouping them into tertiles of fall risk according to these rates. Factors associated independently with falling were fall history, wandering behavior, use of a cane or walker, deterioration of activities of daily living performance, age greater than 87 years, unsteady gait, transfer independence, wheelchair independence, and male gender. Nursing home residents with a fall history were more than three times as likely to fall during the follow-up period than residents without a fall history. Residents in homes with the highest tertile of fall rates were more than twice as likely to fall compared with residents of homes in the lowest tertile, independent of resident-specific risk factors. Fall history was identified as the strongest risk factor associated with subsequent falls and accounted for the vast majority of the predictive strength of the model. We recommend that fall history be used as an initial screener for determining eligibility for fall intervention efforts. Studies are needed to determine the facility characteristics that contribute to fall risk, independent of resident-specific risk factors.
An expert system for the quantification of fault rates in construction fall accidents.
Talat Birgonul, M; Dikmen, Irem; Budayan, Cenk; Demirel, Tuncay
2016-01-01
Expert witness reports, prepared with the aim of quantifying fault rates among parties, play an important role in a court's final decision. However, conflicting fault rates assigned by different expert witness boards lead to iterative objections raised by the related parties. This unfavorable situation mainly originates due to the subjectivity of expert judgments and unavailability of objective information about the causes of accidents. As a solution to this shortcoming, an expert system based on a rule-based system was developed for the quantification of fault rates in construction fall accidents. The aim of developing DsSafe is decreasing the subjectivity inherent in expert witness reports. Eighty-four inspection reports prepared by the official and authorized inspectors were examined and root causes of construction fall accidents in Turkey were identified. Using this information, an evaluation form was designed and submitted to the experts. Experts were asked to evaluate the importance level of the factors that govern fall accidents and determine the fault rates under different scenarios. Based on expert judgments, a rule-based expert system was developed. The accuracy and reliability of DsSafe were tested with real data as obtained from finalized court cases. DsSafe gives satisfactory results.
Risk factors for unintentional injuries due to falls in children aged 0–6 years: a systematic review
Khambalia, A; Joshi, P; Brussoni, M; Raina, P; Morrongiello, B; Macarthur, C
2006-01-01
Objective To identify risk factors for unintentional injuries due to falls in children aged 0–6 years. Design A systematic review of the literature. Methods Electronic databases from 1966 to March 2005 were comprehensively searched to identify empirical research that evaluated risk factors for unintentional injuries due to falls in children aged 0–6 years and included a comparison group. Results 14 studies met the inclusion criteria. Studies varied by the type of fall injury that was considered (ie, bunk bed, stairway, playground or infant walker) and with respect to the quality of evidence. In general, major risk factors for the incidence or severity of injuries due to falls in children included age of the child, sex, height of the fall, type of surface, mechanism (dropped, stairway or using a walker), setting (day care v home care) and socioeconomic status. Conclusion Despite a high burden, few controlled studies have examined the risk and protective factors for injuries due to falls in children aged 0–6 years. The only study to examine falls from a population health perspective suggests that age, sex and poverty are independent risk factors for injuries due to falls in children. PMID:17170185
A wireless transmission neural interface system for unconstrained non-human primates
Fernandez-Leon, Jose A.; Parajuli, Arun; Franklin, Robert; Sorenson, Michael; Felleman, Daniel J.; Hansen, Bryan J.; Hu, Ming; Dragoi, Valentin
2018-01-01
Objective Studying the brain in large animal models in a restrained laboratory rig severely limits our capacity to examine brain circuits in experimental and clinical applications. Approach To overcome these limitations, we developed a high-fidelity 96-channel wireless system to record extracellular spikes and local field potentials from neocortex. A removable, external case of the wireless device is attached to a titanium pedestal placed in the animal skull. Broadband neural signals are amplified, multiplexed, and continuously transmitted as TCP/IP data at a sustained rate of 24 Mbps. A Xilinx Spartan 6 FPGA assembles the digital signals into serial data frames for transmission at 20 kHz though an 802.11n wireless data link on a frequency shift key modulated signal at 5.7-5.8 GHz to a receiver up to 10 m away. The system is powered by two CR123A, 3-V batteries for 2 hours of operation. Main results We implanted a multi-electrode array in visual area V4 of one anesthetized monkey (Macaca fascicularis) and in the dorsolateral prefrontal cortex (dlPFC) of a freely moving monkey (Macaca mulatta). The implanted recording arrays were electrically stable and delivered broadband neural data over a year of testing. For the first time, we compared dlPFC neuronal responses to the same set of stimuli (food reward) in restrained and freely moving conditions. Although we did not find differences in neuronal responses as a function of reward type in the restrained and unrestrained conditions, there were significant differences in correlated activity. This demonstrates that measuring neural responses in freely-moving animals can capture phenomena that are absent in the traditional head-fixed paradigm. Significance We implemented a wireless neural interface for multi-electrode recordings in freely moving non-human primates which can potentially move systems neuroscience to a new direction by allowing to record neural signals while animals interact with their environment. PMID:26269496
A wireless transmission neural interface system for unconstrained non-human primates
NASA Astrophysics Data System (ADS)
Fernandez-Leon, Jose A.; Parajuli, Arun; Franklin, Robert; Sorenson, Michael; Felleman, Daniel J.; Hansen, Bryan J.; Hu, Ming; Dragoi, Valentin
2015-10-01
Objective. Studying the brain in large animal models in a restrained laboratory rig severely limits our capacity to examine brain circuits in experimental and clinical applications. Approach. To overcome these limitations, we developed a high-fidelity 96-channel wireless system to record extracellular spikes and local field potentials from the neocortex. A removable, external case of the wireless device is attached to a titanium pedestal placed in the animal skull. Broadband neural signals are amplified, multiplexed, and continuously transmitted as TCP/IP data at a sustained rate of 24 Mbps. A Xilinx Spartan 6 FPGA assembles the digital signals into serial data frames for transmission at 20 kHz though an 802.11n wireless data link on a frequency-shift key-modulated signal at 5.7-5.8 GHz to a receiver up to 10 m away. The system is powered by two CR123A, 3 V batteries for 2 h of operation. Main results. We implanted a multi-electrode array in visual area V4 of one anesthetized monkey (Macaca fascicularis) and in the dorsolateral prefrontal cortex (dlPFC) of a freely moving monkey (Macaca mulatta). The implanted recording arrays were electrically stable and delivered broadband neural data over a year of testing. For the first time, we compared dlPFC neuronal responses to the same set of stimuli (food reward) in restrained and freely moving conditions. Although we did not find differences in neuronal responses as a function of reward type in the restrained and unrestrained conditions, there were significant differences in correlated activity. This demonstrates that measuring neural responses in freely moving animals can capture phenomena that are absent in the traditional head-fixed paradigm. Significance. We implemented a wireless neural interface for multi-electrode recordings in freely moving non-human primates, which can potentially move systems neuroscience to a new direction by allowing one to record neural signals while animals interact with their environment.
A low-cost, multiplexed μECoG system for high-density recordings in freely moving rodents
NASA Astrophysics Data System (ADS)
Insanally, Michele; Trumpis, Michael; Wang, Charles; Chiang, Chia-Han; Woods, Virginia; Palopoli-Trojani, Kay; Bossi, Silvia; Froemke, Robert C.; Viventi, Jonathan
2016-04-01
Objective. Micro-electrocorticography (μECoG) offers a minimally invasive neural interface with high spatial resolution over large areas of cortex. However, electrode arrays with many contacts that are individually wired to external recording systems are cumbersome and make recordings in freely behaving rodents challenging. We report a novel high-density 60-electrode system for μECoG recording in freely moving rats. Approach. Multiplexed headstages overcome the problem of wiring complexity by combining signals from many electrodes to a smaller number of connections. We have developed a low-cost, multiplexed recording system with 60 contacts at 406 μm spacing. We characterized the quality of the electrode signals using multiple metrics that tracked spatial variation, evoked-response detectability, and decoding value. Performance of the system was validated both in anesthetized animals and freely moving awake animals. Main results. We recorded μECoG signals over the primary auditory cortex, measuring responses to acoustic stimuli across all channels. Single-trial responses had high signal-to-noise ratios (SNR) (up to 25 dB under anesthesia), and were used to rapidly measure network topography within ˜10 s by constructing all single-channel receptive fields in parallel. We characterized evoked potential amplitudes and spatial correlations across the array in the anesthetized and awake animals. Recording quality in awake animals was stable for at least 30 days. Finally, we used these responses to accurately decode auditory stimuli on single trials. Significance. This study introduces (1) a μECoG recording system based on practical hardware design and (2) a rigorous analytical method for characterizing the signal characteristics of μECoG electrode arrays. This methodology can be applied to evaluate the fidelity and lifetime of any μECoG electrode array. Our μECoG-based recording system is accessible and will be useful for studies of perception and decision-making in rodents, particularly over the entire time course of behavioral training and learning.
Insights about Fall Prevention of Older Adults in the State of Hawai'i.
Yamazaki, Yuka; Hayashida, Cullen T; Yontz, Valerie
2017-01-01
The senior population in Hawai'i is growing at a dramatic pace. In the older population, falls and fall-related injuries are leading causes of morbidity and mortality. Moreover, the health care costs for falls are very high. The State of Hawai'i has taken measures to prevent falls through the promotion of medication reviews, vision checks, home assessments, and exercise. However, current published examinations of fall preventive measures have been insufficient, and more research is needed to confirm risk factors, effectiveness of preventive measures, and to explore future objectives. This paper examined the validity of fall risk factors and fall preventive measures for Hawai'i's seniors by conducting mail questionnaire surveys to a sample of seniors using medical alert services from one company in Hawai'i. The results of chi-square analysis suggest that having reduced ability to perform Activities of Daily Living (ADL) and reduced Instrumental Activities of Daily Living (IADL) were associated with a greater risk of falls ( P < .01). In addition, those who fell were more likely to talk about fall preventions with their family members or friends and health providers compared with those who did not ( P = .048 and .003, respectively). Evidence-based exercise programs for strengthening muscles and controlling physical balance may be needed to improve ADL and IADL. Furthermore, the results suggest that seniors do not accept that they are at risk of falling before they actually fall. Public health providers should consider how they approach seniors, and how they inform them of the importance of fall prevention across the life span.
Risk assessment of fall-related occupational accidents in the workplace
Tsukada, Tsukimi; Sakakibara, Hisataka
2016-01-01
Objectives: This study aimed to examine effective assessment methods of falls in the workplace. Methods: There were 436 employees (305 males and 131 females) of electrical appliance manufacturers included in this study. In 2014, a baseline survey was conducted using the fall scores questionnaire and the self-check risk assessment of falls and other accidents in the workplace (physical function measurement and questionnaire). In 2015, the occurrence of falls in the past year was investigated. Multivariate logistic regression analyses were performed to examine factors relevant to falls. Results: In total, 62 subjects (14.2%) fell during the year, including those who fell during off-hours. The occurrence of falls during that one year was only associated with having experienced falls during the past year in the baseline survey (odds ratio [OR] 5.0; 95% confidence interval [CI] 2.5-9.7). Falls during that year were also related to the inability to walk 1 km continuously (OR 0.1; 95% CI 0.1-0.6), tripping sometimes (OR 4.0; 95% CI 1.6-9.9), step height differences at home (OR 3.0; 95% CI 1.3-6.8), and working in the production section (OR 0.2; 95% CI 0.1-0.5). Measurements of physical functions, such as muscle strength, balance, and agility, were not different between subjects who fell and those who did not. Conclusions: Our results showed that the questionnaire assessing falls during the past year could be useful to assess the risk of falls in the workplace. Annual checks for falls may contribute to fall prevention programs in the workplace. PMID:27725487
Rapp, Kilian; Küpper, Michaela; Becker, Clemens; Fischer, Torben; Büchele, Gisela; Benzinger, Petra
2014-01-01
Background Falls and fall-related injuries pose a major threat to older peoples’ health, and are associated with increased morbidity and mortality. In the course of demographic changes, development and implementation of fall prevention strategies have been recognized as an urgent public health challenge. Various risk factors for falls and a number of effective interventions have been recognized. A substantial proportion of falls occur for people who are neither frail nor at high risk. Therefore, population-based approaches reaching the entire older population are needed. Objective The objective of the study presented is the development, implementation, and evaluation of a population-based intervention for the prevention of falls and fall-related injuries in a medium sized city in Germany. Methods The study is designed as a population-based approach. The intervention community is a mid sized city named Reutlingen in southern Germany with a population of 112,700 people. All community dwelling inhabitants 65 years and older are addressed. There are two main measures that are defined: (1) increase of overall physical activity, and (2) reduction of modifiable risk factors for falls such as deficits in strength and balance, home and environmental hazards, impaired vision, unsafe footwear, and improper use of assistive devices. The implementation strategies are developed in a participatory community planning process. These might include, for example, training of professionals and volunteers, improved availability of exercise classes, and education and raising awareness via newspaper, radio, or lectures. Results The study starts in September 2010 and ends in December 2013. It is evaluated primarily by process evaluation as well as by telephone survey. Conclusions Physical activity as a key message entails multiple positive effects with benefits on a range of geriatric symptoms. The strength of the design is the development of implementation strategies in a participatory community planning. The problems that we anticipate are the dependency on the stakeholders’ willingness to participate, and the difficulty of evaluating population-based programs by hard end points. PMID:24686959
Real-time tracking of objects for a KC-135 microgravity experiment
NASA Technical Reports Server (NTRS)
Littlefield, Mark L.
1994-01-01
The design of a visual tracking system for use on the Extra-Vehicular Activity Helper/Retriever (EVAHR) is discussed. EVAHR is an autonomous robot designed to perform numerous tasks in an orbital microgravity environment. Since the ability to grasp a freely translating and rotating object is vital to the robot's mission, the EVAHR must analyze range image generated by the primary sensor. This allows EVAHR to locate and focus its sensors so that an accurate set of object poses can be determined and a grasp strategy planned. To test the visual tracking system being developed, a mathematical simulation was used to model the space station environment and maintain dynamics on the EVAHR and any other free floating objects. A second phase of the investigation consists of a series of experiments carried out aboard a KC-135 aircraft flying a parabolic trajectory to simulate microgravity.
Neurological Gait Abnormalities And Risk Of Falls In Older Adults
Verghese, Joe; Ambrose, Anne F; Lipton, Richard B; Wang, Cuiling
2009-01-01
Objective To estimate the validity of neurological gait evaluations in predicting falls in older adults. Methods We studied 632 adults age 70 and over (mean age 80.6 years, 62% women) enrolled in the Einstein Aging Study whose walking patterns were evaluated by study clinicians using a clinical gait rating scale. Association of neurological gaits and six subtypes (hemiparetic, frontal, Parkinsonian, unsteady, neuropathic, and spastic) with incident falls was studied using generalized estimation equation procedures adjusted for potential confounders, and reported as risk ratio with 95% confidence intervals (CI). Results Over a mean follow-up of 21 months, 244 (39%) subjects fell. Mean fall rate was 0.47 falls per person year. At baseline, 120 subjects were diagnosed with neurological gaits. Subjects with neurological gaits were at increased risk of falls (risk ratio 1.49, 95% CI 1.11 – 2.00). Unsteady (risk ratio 1.52, 95% CI 1.04 – 2.22), and neuropathic gait (risk ratio 1.94, 95% CI 1.07 – 3.11) were the two gait subtypes that predicted risk of falls. The results remained significant after accounting for disability and cognitive status, and also with injurious falls as the outcome. Conclusions Neurological gaits and subtypes are independent predictors of falls in older adults. Neurological gait assessments will help clinicians identify and institute preventive measures in older adults at high risk for falls. PMID:19784714
King, S.E.; Grace, J.B.
2000-01-01
Cogongrass (Imperata cylindrica), an invasive perennial introduced from Southeast Asia, is currently spreading throughout the southeastern United States from Florida to Louisiana. In the U.S., cogongrass is generally not considered a wetland species, although it's range is expanding in regions with high wetland abundance. The objective of this study was to determine if excessive soil moisture might prevent cogongrass from establishing in areas with seasonally flooded soils. In one greenhouse experiment, we examined cogongrass germination and seedling growth in soils that were freely drained, saturated, and inundated. We performed a second greenhouse experiment to evaluate growth and survival of cogongrass seedlings of four different size classes in five soil moisture treatments ranging from dry to inundated. Cogongrass germination was lowest when seeds were overtopped with water. There were no differences in germination between saturated and freely drained treatments; however, seedlings grew largest in freely drained soil and were smallest when immersed. In our second experiment, most cogongrass plants survived except when given no water, but growth differed by watering treatment depending on seedling size. Increasing moisture was more detrimental to the growth of small seedlings compared to the growth of larger cogongrass plants. Overall, cogongrass was most sensitive to soil inundation in the earliest stages of establishment; thus, excessive moisture conditions in the spring, during early seedling development, could restrict invasion of cogongrass by seed. Once cogongrass is established, however, its tolerance of flooding appears to increase.
Fall predictors in older cancer patients: a multicenter prospective study.
Vande Walle, Nathalie; Kenis, Cindy; Heeren, Pieter; Van Puyvelde, Katrien; Decoster, Lore; Beyer, Ingo; Conings, Godelieve; Flamaing, Johan; Lobelle, Jean-Pierre; Wildiers, Hans; Milisen, Koen
2014-12-15
In the older population falls are a common problem and a major cause of morbidity, mortality and functional decline. The etiology is often multifactorial making the identification of fall predictors essential for preventive measures. Despite this knowledge, data on falls within the older cancer population are limited. The objective of this study was to evaluate the occurrence of falls within 2 to 3 months after cancer treatment decision and to identify predictors of falls (≥1 fall) during follow-up. Older patients (70 years or more) with a cancer treatment decision were included. At baseline, all patients underwent geriatric screening (G8 and Flemish Triage Risk Screening Tool), followed by a geriatric assessment including living situation, activities of daily living (ADL), instrumental activities of daily living (IADL), fall history in the past 12 months, fatigue, cognition, depression, nutrition, comorbidities and polypharmacy. Questionnaires were used to collect follow-up (2-3 months) data. Univariate and multivariate analyses were performed to identify predictors for falls (≥1 fall) during follow-up. At baseline, 295 (31.5%) of 937 included patients reported at least one fall in the past 12 months with 88 patients (29.5%) sustaining a major injury. During follow-up (2-3 months), 142 (17.6%) patients fell, of whom 51.4% fell recurrently and 17.6% reported a major injury. Baseline fall history in the past 12 months (OR = 3.926), fatigue (OR = 0.380), ADL dependency (OR = 0.492), geriatric risk profile by G8 (OR = 0.471) and living alone (OR = 1.631) were independent predictors of falls (≥1 fall) within 2-3 months after cancer treatment decision. Falls are a serious problem among older cancer patients. Geriatric screening and assessment data can identify patients at risk for a fall. A patient with risk factors associated with falls should undergo further evaluation and intervention to prevent potentially injurious fall incidents.
Fall Prevention in Acute Care Hospitals
Dykes, Patricia C.; Carroll, Diane L.; Hurley, Ann; Lipsitz, Stuart; Benoit, Angela; Chang, Frank; Meltzer, Seth; Tsurikova, Ruslana; Zuyov, Lyubov; Middleton, Blackford
2011-01-01
Context Falls cause injury and death for persons of all ages, but risk of falls increases markedly with age. Hospitalization further increases risk, yet no evidence exists to support short-stay hospital-based fall prevention strategies to reduce patient falls. Objective To investigate whether a fall prevention tool kit (FPTK) using health information technology (HIT) decreases patient falls in hospitals. Design, Setting, and Patients Cluster randomized study conducted January 1, 2009, through June 30, 2009, comparing patient fall rates in 4 urban US hospitals in units that received usual care (4 units and 5104 patients) or the intervention (4 units and 5160 patients). Intervention The FPTK integrated existing communication and workflow patterns into the HIT application. Based on a valid fall risk assessment scale completed by a nurse, the FPTK software tailored fall prevention interventions to address patients’ specific determinants of fall risk. The FPTK produced bed posters composed of brief text with an accompanying icon, patient education handouts, and plans of care, all communicating patient-specific alerts to key stakeholders. Main Outcome Measures The primary outcome was patient falls per 1000 patient-days adjusted for site and patient care unit. A secondary outcome was fall-related injuries. Results During the 6-month intervention period, the number of patients with falls differed between control (n=87) and intervention (n=67) units (P=.02). Site-adjusted fall rates were significantly higher in control units (4.18 [95% confidence interval {CI}, 3.45-5.06] per 1000 patient-days) than in intervention units (3.15 [95% CI, 2.54-3.90] per 1000 patient-days; P=.04). The FPTK was found to be particularly effective with patients aged 65 years or older (adjusted rate difference, 2.08 [95% CI, 0.61-3.56] per 1000 patient-days; P=.003). No significant effect was noted in fall-related injuries. Conclusion The use of a fall prevention tool kit in hospital units compared with usual care significantly reduced rate of falls. PMID:21045097
Boyer, Elizabeth R; Patterson, Aleksys
2018-05-05
Trips and falls are common concerns reported by parents of children with cerebral palsy. Specific gait pathologies (excessive internal hip rotation, intoeing, and stiff knee gait) are anecdotally associated with higher rates of falls. Is fall frequency higher for the aforementioned gait pathologies? Parent-reported fall frequency from 1063 children with cerebral palsy who also had a three-dimensional gait analysis was retrospectively reviewed. Frequency of 10 common gait pathologies was determined and fall frequency for the gait pathologies of interest were compared to matched control groups. Possible effects of Gross Motor Functional Classification System (GMFCS) level and age on fall frequency were also assessed and matched in the control group, as appropriate. In general, parent-reported fall frequency increased from GMFCS level I to II and then decreased until level IV. Moreover, younger children tended to report greater fall frequency, though children who reported never falling were of similar age as those who reported weekly falls, resulting in an inverted-U shaped relationship. Children with cerebral palsy who walked with excessive internal hip rotation, excessive intoeing, or stiff knee gait did not report increased fall frequencies compared to other children with cerebral palsy matched on GMFCS level and age that did not walk with those gait patterns. Approximately 35% of children reported never falling, 35% reported falling daily, and 30% reported falling monthly or weekly for each gait pattern. Therefore, elevated fall frequency appears to be a generic problem for most children with CP rather than a function of a specific gait pattern. Clinicians should be aware of these relationships, or lack thereof, when trying to decipher the cause of a child's falling and when determining appropriate interventions. Future studies may seek to more objectively quantify fall frequency, as self-report is the main limitation of this study. Copyright © 2018 Elsevier B.V. All rights reserved.
Hayakawa, Takehito; Hashimoto, Shigeatsu; Kanda, Hideyuki; Hirano, Noriko; Kurihara, Yumi; Kawashima, Takako; Fukushima, Tetsuhito
2014-01-01
Objectives To clarify the risk factors for falls in hospital settings and to propose the use of such factors to identify high-risk persons at admission. Design Prospective cohort study. Setting Fukushima Medical University Hospital, Japan, from August 2008 and September 2009. Participants 9957 adult consecutive inpatients admitted to our hospital. Methods Information was collected at admission from clinical records obtained from a structured questionnaire conducted in face-to-face interviews with subjects by nurses and doctors and fall events were collected from clinical records. Results The proportion of patients who fell during follow-up was 2.5% and the incidence of falls was 3.28 per 100 person-days. There were significant differences in age, history of falling, cognitive dysfunction, planned surgery, wheelchair use, need for help to move, use of a remote caring system, rehabilitation, use of laxative, hypnotic or psychotropic medications and need for help with activities of daily living (ADL) between patients who did and did not fall. Multivariable adjusted ORs for falls showed that age, history of falls and need for help with ADL were common risk factors in both men and women. Using psychotropic medication also increased the risk of falling in men while cognitive dysfunction and use of hypnotic medication increased the risk of falling in women. Planned surgery was associated with a low risk of falls in women. Conclusions To prevent falls in inpatients it is important to identify high-risk persons. Age, history of falling and the need for help with ADL are the most important pieces of information to be obtained at admission. Care plans for patients including fall prevention should be clear and considered. PMID:25232563
Hanlin, Erin R; Delgado-Rendón, Angélica; Lerner, E Brooke; Hargarten, Stephen; Farías, René
2013-01-01
The impact of falls in older adults presents a significant public health burden. Fall risk is not well-described in Latino populations nor have fall prevention programs considered the needs of this population. The objectives of this study were to develop a needs assessment of falls in older adult Latinos at a community center (CC), determine fall prevention barriers and strengths in this population, determine the level of interest in various fall prevention methods, and provide medical students an opportunity for participation in a culturally diverse community project. A cross-sectional survey was conducted with a convenience sample of older adult program participants. The survey was developed in collaboration with both partners. CC participants were approached by the interviewer and asked to participate. They were read the survey in their preferred language and their answers were recorded. Data were analyzed using descriptive statistics. We conducted 103 interviews. We found that 54% of participants had fallen in the last year, and of those 21% required medical care, 81% were afraid of falling again, and 66% considered themselves at risk for falling again. Of all respondents, 52% had 5 or more of the 10 surveyed risk factors for falling; 4% had no risk factors. Of all respondents, 75% were afraid of falling. Talking with health care providers and participating in an exercise class were the preferred methods of health information delivery (78% and 65%, respectively). Older adult Latinos in this selected population frequently fall and are worried about falling. Risk factors are prevalent. A fall prevention program is warranted and should include exercise classes and a connection with local primary care providers. A partnership between an academic organization and a CC is an ideal collaboration for the future development of prevention program.
Epstein, Noam U.; Guo, Rong; Farlow, Martin R.; Singh, Jaswinder P.; Fisher, Morris
2014-01-01
Background Falls are common in the elderly, especially in those with cognitive impairment. The elderly are often treated with several medications which may have both beneficial and deleterious effects. The use and type of medication in Alzheimer’s patients and association with falls is limited. Objective We examined the association between falls and medication use in the Alzheimer’s Disease Neuro-Imaging Initiative (ADNI). Methods Diagnosis, demographics, medication use, apolipoprotein E4 allele status and functional activity level at baseline were gathered for 810 participants enrolled in ADNI including healthy controls and subjects with mild cognitive impairment or Alzheimer’s. Adverse event fall reports were tabulated. Baseline characteristics were compared between subjects with and without one or more falls. Cox proportional hazards models were conducted to evaluate the association between subject characteristics and hazard of first fall. Results Age (p<0.0001), functional activities questionnaire (p=0.035), Beers list (p=0.0477) and medications for treating cognitive symptoms of Alzheimer’s (p=0.0019) were associated with hazard of fall in the univariate model. In the final multivariate model, after adjusting for covariates, Alzheimer’s medication use (p=0.0005) was associated with hazard of fall. Medication was changed after an adverse fall event by the clinician in 9% of the falls. About 7% of the falls were reported as serious adverse events and 6% were reported to be severe. Conclusion We found a significant association between use of symptomatic medication treating cognitive symptoms in Alzheimer’s disease and hazard of fall after adjusting for age and Beers list medication use. Additional pharmaco-vigilance of the association between falls and Alzheimer’s medication use is warranted. PMID:24357133
Identifying Home Care Clinicians’ Information Needs for Managing Fall Risks
Alhuwail, Dari
2016-01-01
Summary Objectives To help manage the risk of falls in home care, this study aimed to (i) identify home care clinicians’ information needs and how they manage missing or inaccurate data, (ii) identify problems that impact effectiveness and efficiency associated with retaining, exchanging, or processing information about fall risks in existing workflows and currently adopted health information technology (IT) solutions, and (iii) offer informatics-based recommendations to improve fall risk management interventions. Methods A case study was carried out in a single not-for-profit suburban Medicare-certified home health agency with three branches. Qualitative data were collected over a six month period through observations, semi-structured interviews, and focus groups. The Framework method was used for analysis. Maximum variation sampling was adopted to recruit a diverse sample of clinicians. Results Overall, the information needs for fall risk management were categorized into physiological, care delivery, educational, social, environmental, and administrative domains. Examples include a brief fall-related patient history, weight-bearing status, medications that affect balance, availability of caregivers at home, and the influence of patients’ cultures on fall management interventions. The unavailability and inaccuracy of critical information related to fall risks can delay necessary therapeutic services aimed at reducing patients’ risk for falling and thereby jeopardizing their safety. Currently adopted IT solutions did not adequately accommodate data related to fall risk management. Conclusion The results highlight the essential information for fall risk management in home care. Home care workflows and health IT solutions must effectively and efficiently retain, exchange, and process information necessary for fall risk management. Interoperability and integration of the various health IT solutions to make data sharing accessible to all clinicians is critical for fall risk management. Findings from this study can help home health agencies better understand their information needs to manage fall risks. PMID:27437035
DOE Office of Scientific and Technical Information (OSTI.GOV)
Patton, Gregory W; Dauble, Dennis D; Chamness, Mickie A
The objective of this study was to evaluate site-specific effects for early life-stage (eyed eggs to free swimming juveniles) fall chinook salmon that might be exposed to hexavalent chromium from Hanford groundwater sources. Our exposure conditions included hexavalent chromium obtained from Hanford groundwater wells near the Columbia River, Columbia River water as the diluent, and locally adapted populations of fall chinook salmon. This report describes both a 96-hr pretest using rainbow trout eggs and an early life-stage test beginning with chinook salmon eggs.
Handrigan, G A; Maltais, N; Gagné, M; Lamontagne, P; Hamel, D; Teasdale, N; Hue, O; Corbeil, P; Brown, J P; Jean, S
2017-02-01
This study investigated the relationship between body mass index (BMI) and falls among community-dwelling elderly. Results indicate that obesity is associated with increased falls and there appears to be a sex-specific difference with obese men at higher risk of falling. Obesity is identified as a risk factor for falls in men. The prevalence of falls, fall-related injuries, and obesity has increased over the last decade. The objectives of this study were to investigate sex-specific association and dose-response relationship between BMI and falls (and related injuries) among community-dwelling elderly. Our study sample consisted of 15,860 adults aged 65 years or older (6399 men and 9461 women) from the 2008-2009 Canadian Community Health Survey-Healthy Aging (CCHS-HA). Falls, fall-related injuries, and BMI measures were self-reported. For both sex, dose-response curves presenting the relationship between BMI, falls, and fall-related injuries were first examined. Thereafter, multivariate logistic regression analyses were also performed to investigate these relationships after adjustment for potentially confounding variables. Of women, 21.7 % reported a fall and 16.9 % of men. The dose-response relationship between BMI and prevalence of falls showed that underweight and obese individuals reported falling more than normal and overweight individuals; this being more apparent in men than women. Finally, the dose relationship between BMI and prevalence of fall-related injuries showed that only obese men seem more likely to have sustained a fall-related injury. Results from the multivariate analysis showed that obesity in men was significantly associated with higher odds of falling odds ratio (OR) 1.33 (1.04-1.70) and was not significantly associated with higher odds of fall-related injuries OR 1.10 (0.66-1.84) over a 12-month period compared to normal weight men. For women, obesity was not significantly associated with higher fall prevalence OR 0.99 (0.79-1.25) and fall-related injuries OR 0.71 (0.51-1.00). Obesity is associated with self-reported falls, and there appears to be a sex-specific difference in elderly persons.
Blood pressure and falls in community-dwelling people aged 60 years and older in the VHM&PP cohort.
Klein, Diana; Nagel, Gabriele; Kleiner, Andrea; Ulmer, Hanno; Rehberger, Barbara; Concin, Hans; Rapp, Kilian
2013-05-21
Falls are one of the major health problems in old people. Different risk factors were identified but only few epidemiological studies analysed the influence of conventionally measured blood pressure on falls. The objective of our study was to investigate the relationship between systolic and diastolic blood pressure and falls. In 3,544 community-dwelling Austrian women and men aged 60 years and older, data on falls within the previous three months were collected by questionnaire. Blood pressure was measured by general practitioners within the Vorarlberg Health Monitoring and Prevention Programme (VHM&PP) 90 to 1095 days before the fall assessment. A multiple logistic regression analysis was conducted. The models were stratified by gender and adjusted by age, number of medical conditions and subjective feeling of illness. In total, 257 falls in 3,544 persons were reported. In women, high systolic and diastolic blood pressure was associated with a decreased risk of falls. An increase of systolic blood pressure by 10 mmHg and of diastolic blood pressure by 5 mmHg reduced the risk of falling by 9% (OR 0.91, 95% Cl 0.84-0.98) and 8% (OR 0.92, 95% Cl 0.85-0.99), respectively. In men, an increased risk of falls was observed in participants with low systolic or low diastolic blood pressure. Blood pressure was associated with the risk of falls. Hypertensive values decreased the risk in women and low blood pressure increased the risk in men.
Bayramzadeh, Sara; Portillo, Margaret; Carmel-Gilfilen, Candy
2018-05-01
The influence of the physical environment on patient falls has not been fully explored in psychiatric units, despite this patient population's vulnerability and the critical role of the physical environment in patient safety. The research objective is to describe the spatial and temporal pattern of falls occurrences and their location in relation to the levels of safety continuum model. This article presents an exploratory case study design. Seven years of retrospective data on patient falls, yielding 818 sentinel events, in an 81-bed psychiatric hospital in the United States were collected and analyzed. Data focused on extrinsic factors for falls, emphasizing the physical environment. Through a content analysis of the sentinel event narratives, recorded by the hospital staff, this study explored patient falls related to location and elements of the physical environment. The analysis revealed that 15% of recorded falls were attributed to some aspect of or element within the physical environment. The most typical locations of falls were patient rooms (39%), patient bathrooms (22%), and dayrooms (20%). Also, the results identified patterns of environmental factors that appeared linked to increasing patients' susceptibility to falls. Risk factors included poor nighttime lighting, flooring surfaces that were uneven, and spaces that inadvertently limited visual access and supervision. The physical environment plays an often-unexamined role in fall events and specific locations. These results are deserving of further research on design strategies and applications to reduce patient falls in psychiatric hospital settings.
Our Environment in Miniature: Dust and the Early Twentieth-Century Forensic Imagination
BURNEY, IAN
2013-01-01
This article explores the articulation of the crime scene as a distinct space of theory and practice in the early twentieth century. In particular it focuses on the evidentiary hopes invested in what would at first seem an unpromising forensic object: dust. Ubiquitous and, to the uninitiated, characterless, dust nevertheless featured as an exemplary object of cutting-edge forensic analysis in two contemporary domains: writings of criminologists and works of detective fiction. The article considers how in these texts dust came to mark the furthest reach of a new forensic capacity they were promoting, one that drew freely upon the imagination to invest crime scene traces with meaning. PMID:23766552
Jayawardhana, Ananda; Burman, Mary E.; Dunton, Nancy E.; Staggs, Vincent S.; Bergquist-Beringer, Sandra; Gajewski, Byron J.
2016-01-01
Background Composite indices are single measures that combine the strengths of two or more individual measures and provide broader, easy-to-use measures for evaluation of provider performance and comparisons across units and hospitals to support quality improvement. Objective The study objective was to develop a unit-level inpatient composite nursing care quality performance index – the Pressure Ulcer and Fall Rate Quality Composite Index. Design Two-phase measure development study. Settings 5,144 patient care units in 857 United States hospitals participating in the National Database of Nursing Quality Indictors® during the year 2013. Methods The Pressure Ulcer and Fall Rate Quality Composite Index was developed in two phases. In Phase 1 the formula was generated using a utility function and generalized penalty analysis. Experts with experience in healthcare quality measurement provided the point of indicator equivalence. In Phase 2 initial validity evidence was gathered based on hypothesized relationships between the Pressure Ulcer and Fall Rate Quality Composite Index and other variables using two-level (unit, hospital) hierarchical linear mixed modeling. Results The Pressure Ulcer and Fall Rate Quality Composite Index = 100 − PUR − FR, where PUR is pressure ulcer rate and FR is total fall rate. Higher scores indicate better quality. Bland-Altman plots demonstrated agreement between pairs of experts and provided evidence for inter-rater reliability of the formula. The validation process demonstrated that higher registered nurse skill mix, higher percent of registered nurses with a baccalaureate in nursing or higher degree, higher percent of registered nurses with national specialty certification, and lower percent of hours supplied by agency staff were significantly associated with higher Pressure Ulcer and Fall Rate Quality Composite Index scores. Higher percentages of unit patients at risk for a hospital-acquired pressure ulcer and higher unit rates of physical restraint use were not associated with higher Pressure Ulcer and Fall Rate Quality Composite Index scores. Conclusions The Pressure Ulcer and Fall Rate Quality Composite Index is a step toward providing a more holistic perspective of unit level nursing quality than individual measures and may help nurses nursing administrators obtain a broader view of which patient care units are the higher and lower performers. Further study is needed to examine the usability of the Pressure Ulcer and Fall Rate Quality Composite Index. PMID:27607602
Franse, Carmen B; Rietjens, Judith AC; Burdorf, Alex; van Grieken, Amy; Korfage, Ida J; van der Heide, Agnes; Mattace Raso, Francesco; van Beeck, Ed; Raat, Hein
2017-01-01
Objectives The rate of falling among older citizens appears to vary across different countries, but the underlying aspects causing this variation are unexplained. We aim to describe between-country variation in falling and explore whether intrinsic fall risk factors can explain possible variation. Design Prospective study on data from the cross-national Survey of Health, Ageing and Retirement in Europe (SHARE). Setting Twelve European countries (Austria, Belgium, Czech Republic, Denmark, Estonia, France, Germany, Italy, The Netherlands, Spain, Sweden, Switzerland). Participants Community-dwelling persons aged ≥65 years (n=18 596). Measurements Socio-demographic factors (age, gender, education level and living situation) and intrinsic fall risk factors (less than good self-rated health (SRH), mobility limitations, limitations with activities of daily living (ADL), dizziness, impaired vision, depression and impaired cognition) were assessed in a baseline interview. Falling was assessed 2 years later by asking whether the participant had fallen within the 6 months prior to the follow-up interview. Results There was significant between-country variation in the rate of falling (varying from 7.9% in Switzerland to 16.2% in the Czech Republic). The prevalence of intrinsic fall risk factors varied twofold to fourfold between countries. Associations between factors age ≥80 years, less than good SRH, mobility limitations, ADL limitations, dizziness and depression, and falling were different between countries (p<0.05). Between-country differences in falling largely persisted after adjusting for socio-demographic differences but strongly attenuated after adjusting for differences in intrinsic fall risk factors. Conclusion There is considerable variation in the rate of falling between European countries, which can largely be explained by between-country variation in the prevalence of intrinsic fall risk factors. There are also country-specific variations in the association between these intrinsic risk factors and falling. These findings emphasise the importance of addressing intrinsic fall risk in (inter)national fall-prevention strategies, while highlighting country-specific priorities. PMID:28667220
Fall risk as a function of time after admission to sub-acute geriatric hospital units.
Rapp, Kilian; Ravindren, Johannes; Becker, Clemens; Lindemann, Ulrich; Jaensch, Andrea; Klenk, Jochen
2016-10-07
There is evidence about time-dependent fracture rates in different settings and situations. Lacking are data about underlying time-dependent fall risk patterns. The objective of the study was to analyse fall rates as a function of time after admission to sub-acute hospital units and to evaluate the time-dependent impact of clinical factors at baseline on fall risk. This retrospective cohort study used data of 5,255 patients admitted to sub-acute units in a geriatric rehabilitation clinic in Germany between 2010 and 2014. Falls, personal characteristics and functional status at admission were extracted from the hospital information system. The rehabilitation stay was divided in 3-day time-intervals. The fall rate was calculated for each time-interval in all patients combined and in subgroups of patients. To analyse the influence of covariates on fall risk over time multivariate negative binomial regression models were applied for each of 5 time-intervals. The overall fall rate was 10.2 falls/1,000 person-days with highest fall risks during the first week and decreasing risks within the following weeks. A particularly pronounced risk pattern with high fall risks during the first days and decreasing risks thereafter was observed in men, disoriented people, and people with a low functional status or impaired cognition. In disoriented patients, for example, the fall rate decreased from 24.6 falls/1,000 person-days in day 2-4 to about 13 falls/1,000 person-days 2 weeks later. The incidence rate ratio of baseline characteristics changed also over time. Fall risk differs considerably over time during sub-acute hospitalisation. The strongest association between time and fall risk was observed in functionally limited patients with high risks during the first days after admission and declining risks thereafter. This should be considered in the planning and application of fall prevention measures.
Garcia, Patrícia A.; Dias, João M. D.; Silva, Silvia L. A.; Dias, Rosângela C.
2015-01-01
Background: The identification of the occurrence of falls is an important step for screening and for rehabilitation processes for the elderly. The methods of monitoring these events are susceptible to recording biases, and the choice of the most accurate method remains challenging. Objectives: (i) To investigate the agreement between retrospective self-reporting and prospective monitoring of methods of recording falls, and (ii) to compare the retrospective self-reporting of falls and the prospective monitoring of falls and recurrent falls over a 12-month period among older women at high risk of falls and fractures. Method: A total of 118 community-dwelling older women with low bone density were recruited. The incidence of falls was monitored prospectively in 116 older women (2 losses) via monthly phone calls over the course of a year. At the end of this monitoring period, the older women were asked about their recall of falls in the same 12-month period. The agreement between the two methods was analyzed, and the sensitivity and specificity of self-reported previous falls in relation to the prospective monitoring were calculated. Results: There was moderate agreement between the prospective monitoring and the retrospective self-reporting of falls in classifying fallers (Kappa=0.595) and recurrent fallers (Kappa=0.589). The limits of agreement were 0.35±1.66 falls. The self-reporting of prior falls had a 67.2% sensitivity and a 94.2% specificity in classifying fallers among older women and a 50% sensitivity and a 98.9% specificity in classifying recurrent fallers. Conclusion: Self-reporting of falls over a 12-month period underestimated 32.8% of falls and 50% of recurrent falls. The findings recommend caution if one is considering replacing monthly monitoring with annual retrospective questioning. PMID:26083603
ERIC Educational Resources Information Center
Heuristics, Inc., Dedham, MA.
This report presents the evaluation of the 1973-1974 Fall River Middle School Research and Development Center, a project funded by ESEA Title VII as a model demonstration bilingual program beginning in 1972-1973. The evaluation focused on the assessment of the degree of accomplishment of product objectives for each component of the program. The…
ERIC Educational Resources Information Center
Ferreira, Annalize; Seyffert, Albertus S.; Lemmer, Miriam
2017-01-01
Many students find it difficult to apply certain physics concepts to their daily lives. This is especially true when they perceive a principle taught in physics class as being in conflict with their experience. An important instance of this occurs when students are instructed to ignore the effect of air resistance when solving kinematics problems.…
This report documents the activities performed during and the results obtained from the arsenic removal treatment technology demonstration project at Oregon Institute of Technology (OIT) at Klamath Falls, OR. The objectives of the project were to evaluate: (1) the effectiveness...
ERIC Educational Resources Information Center
Henning, Mark C.
2007-01-01
The main objective of this study was to gauge preparedness in math with achievement in first semester math for the fall 2005 intake of Manufacturing Sciences Division post-secondary program students. The data used to measure this level of preparedness was gleaned from students' high school Grade 12 (new and old curriculum) or Ontario Academic…
Femur loading in feet-first fall experiments using an anthropomorphic test device.
Thompson, Angela; Bertocci, Gina; Smalley, Craig
2018-03-31
Femur fractures are a common orthopedic injury in young children. Falls account for a large portion of accidental femur fractures in young children, but there is also a high prevalence of femur fractures in child abuse, with falls often provided as false histories. Objective information regarding fracture potential in short distance fall scenarios may aid in assessing whether a child's injuries are the result of abuse or an accidental fall. Knowledge of femur loading is the first step towards understanding likelihood of fracture in a fall. Characterize femur loading during feet-first free falls using a surrogate representing a 12-month-old child. The femur and hip joint of a surrogate representing a 12-month-old were modified to improve biofidelity and measure femur loading; 6-axis load cells were integrated into the proximal and distal femur. Femur modification was based upon CT imaging of cadaveric femurs in children 10-14 months of age. Using the modified 12-month-old surrogate, feet-first free falls from 69 cm and 119 cm heights onto padded carpet and linoleum were conducted to assess fall dynamics and determine femur loading. Femur compression, bending moment, shear and torsional moment were measured for each fall. Fall dynamics differed across fall heights, but did not substantially differ by impact surface type. Significant differences were found in all loading conditions across fall heights, while only compression and bending loads differed between carpet and linoleum surfaces. Maximum compression, bending, torsion and shear occurred in 119 cm falls and were 572 N, 23 N-m, 11 N-m and 281 N, respectively. Fall dynamics play an important role in the biomechanical assessment of falls. Fall height was found to influence both fall dynamics and femur loading, while impact surface affected only compression and bending in feet-first falls; fall dynamics did not differ across carpet and linoleum. Improved pediatric thresholds are necessary to predict likelihood of fracture, but morphologically accurate representation of the lower extremity, along with accurate characterization of loading in falls are a crucial first step. Copyright © 2018 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.
Influence of age and fall type on head injuries in infants and toddlers
Ibrahim, Nicole G.; Wood, Joanne; Margulies, Susan S.; Christian, Cindy W.
2011-01-01
Age-based differences in fall type and neuroanatomy in infants and toddlers may affect clinical presentations and injury patterns. Objective Our goal is to understand the influence of fall type and age on injuries to help guide clinical evaluation. Design/Setting/Participants Retrospectively, 285 children 0–48 months with accidental head injury from a fall and brain imaging between 2000–2006 were categorized by age (infant=<1 year and toddler=1–4 years) and fall type: low (≤3 ft), intermediate (>3 and <10 ft), high height falls (≥10 ft) and stair falls. Outcome Measures Clinical manifestations were noted and head injuries separated into primary (bleeding) and secondary (hypoxia, edema). The influence of age and fall type on head injuries sustained was evaluated. Results Injury patterns in children <4 yrs varied with age. Despite similar injury severity scores, infants sustained more skull fractures than toddlers (71% v. 39%). Of children with skull fractures, 11% had no evidence of scalp/facial soft tissue swelling. Of the patients with primary intracranial injury, 30% had no skull fracture and 8% had neither skull fracture nor cranial soft tissue injury. Low height falls resulted in primary intracranial injury without soft tissue or skull injury in infants (6%) and toddlers (16%). Conclusions Within a given fall type, age-related differences in injuries exist between infants and toddlers. When interpreting a fall history, clinicians must consider the fall type and influence of age on resulting injury. For young children, intracranial injury is not always accompanied by external manifestations of their injury. PMID:22079853
Liu, Shan W; Sri-On, Jiraporn; Tirrell, Gregory Philip; Nickel, Christian; Bingisser, Roland
2016-08-01
Falls among older adults are a public health problem and are multifactorial. We sought to determine whether falls predict more serious conditions in older adult patients presenting to the emergency department (ED) with a "nonspecific complaint" (NSC). A secondary objective was to examine what factors predicted serious conditions among older adult patients with a fall. This study was a secondary analysis of a prospective delayed-type cross-sectional diagnostic study that included a 30-day follow-up. We included patients 65 years and older who presented to the ED from May 2007 and July 2011 with a NSC and had an Emergency Severity Index score of 2 or 3. We then compared the serious conditions among older adults who presented to the ED with a fall with those who did not fall in a cohort of patients with NSC. We had 1111 patients enrolled in our study; 518 (47%) of them had fallen. We found that 310 (60%) of elderly fall patients vs 349 (59%) of nonfall patients had a 30-day serious condition (P=.74). In multiple logistic regression analysis, falls did not predict serious conditions or 30-day mortality among all NSC patients. Among fall patients, male sex, diuretic use, and generalized weakness predicted serious conditions. Fall patients share many features with nonfall NSC patient. However, falls did not increase the risk of serious conditions. Falls in the elderly could be considered under the broader entity of NSC. Copyright © 2016 Elsevier Inc. All rights reserved.
Distinguishing the causes of falls in humans using an array of wearable tri-axial accelerometers.
Aziz, Omar; Park, Edward J; Mori, Greg; Robinovitch, Stephen N
2014-01-01
Falls are the number one cause of injury in older adults. Lack of objective evidence on the cause and circumstances of falls is often a barrier to effective prevention strategies. Previous studies have established the ability of wearable miniature inertial sensors (accelerometers and gyroscopes) to automatically detect falls, for the purpose of delivering medical assistance. In the current study, we extend the applications of this technology, by developing and evaluating the accuracy of wearable sensor systems for determining the cause of falls. Twelve young adults participated in experimental trials involving falls due to seven causes: slips, trips, fainting, and incorrect shifting/transfer of body weight while sitting down, standing up from sitting, reaching and turning. Features (means and variances) of acceleration data acquired from four tri-axial accelerometers during the falling trials were input to a linear discriminant analysis technique. Data from an array of three sensors (left ankle+right ankle+sternum) provided at least 83% sensitivity and 89% specificity in classifying falls due to slips, trips, and incorrect shift of body weight during sitting, reaching and turning. Classification of falls due to fainting and incorrect shift during rising was less successful across all sensor combinations. Furthermore, similar classification accuracy was observed with data from wearable sensors and a video-based motion analysis system. These results establish a basis for the development of sensor-based fall monitoring systems that provide information on the cause and circumstances of falls, to direct fall prevention strategies at a patient or population level. Copyright © 2013 Elsevier B.V. All rights reserved.
Emerald: an object-based language for distributed programming
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hutchinson, N.C.
1987-01-01
Distributed systems have become more common, however constructing distributed applications remains a very difficult task. Numerous operating systems and programming languages have been proposed that attempt to simplify the programming of distributed applications. Here a programing language called Emerald is presented that simplifies distributed programming by extending the concepts of object-based languages to the distributed environment. Emerald supports a single model of computation: the object. Emerald objects include private entities such as integers and Booleans, as well as shared, distributed entities such as compilers, directories, and entire file systems. Emerald objects may move between machines in the system, but objectmore » invocation is location independent. The uniform semantic model used for describing all Emerald objects makes the construction of distributed applications in Emerald much simpler than in systems where the differences in implementation between local and remote entities are visible in the language semantics. Emerald incorporates a type system that deals only with the specification of objects - ignoring differences in implementation. Thus, two different implementations of the same abstraction may be freely mixed.« less
High fall incidence and fracture rate in elderly dialysis patients.
Polinder-Bos, H A; Emmelot-Vonk, M H; Gansevoort, R T; Diepenbroek, A; Gaillard, C A J M
2014-12-01
Although it is recognised that the dialysis population is ageing rapidly, geriatric complications such as falls are poorly appreciated, despite the many risk factors for falls in this population. The objective of this study was to determine the incidence, complications and risk factors for falls in an elderly dialysis population. A one-year observational study of chronic dialysis patients aged ≥ 70 years. At baseline, patient characteristics were noted and during follow-up the vital parameters and laboratory values were recorded. Patients were questioned weekly about falls, fall circumstances and consequences by trained nurses. 49 patients were included with a median age of 79.3 years (70-89 years). During follow-up 40 fall accidents occurred in 27 (55%) patients. Falls resulted in fractures in 15% of cases and in hospital admissions in 15%. In haemodialysis (HD) patients, the mean systolic blood pressure (SBP) before HD was lower in fallers compared with non-fallers (130 vs. 143 mmHg). Several patients in the lower blood pressure category received antihypertensive medication. For every 5 mmHg lower SBP (before HD) the fall risk increased by 30% (hazard ratio (HR) 1.30, 95% CI 1.03-1.65, p = 0.03). Furthermore, fall risk increased by 22% for every 10 pmol/l rise of parathyroid hormone (HR 1.22, 95% CI 1.06-1.39, p = 0.004). Elderly dialysis patients have a high incidence of falls accompanied by a high fracture rate. Given the high complication rate, elderly patients at risk of falling should be identified and managed. Reduction of blood pressure-lowering medication might be a treatment strategy to reduce falls.
2014-01-01
Background In line with a rapidly ageing global population, the rise in the frequency of falls will lead to increased healthcare and social care costs. This study will be one of the few randomized controlled trials evaluating a multifaceted falls intervention in a low-middle income, culturally-diverse older Asian community. The primary objective of our paper is to evaluate whether individually tailored multifactorial interventions will successfully reduce the number of falls among older adults. Methods Three hundred community-dwelling older Malaysian adults with a history of (i) two or more falls, or (ii) one injurious fall in the past 12 months will be recruited. Baseline assessment will include cardiovascular, frailty, fracture risk, psychological factors, gait and balance, activities of daily living and visual assessments. Fallers will be randomized into 2 groups: to receive tailored multifactorial interventions (intervention group); or given lifestyle advice with continued conventional care (control group). Multifactorial interventions will target 6 specific risk factors. All participants will be re-assessed after 12 months. The primary outcome measure will be fall recurrence, measured with monthly falls diaries. Secondary outcomes include falls risk factors; and psychological measures including fear of falling, and quality of life. Discussion Previous studies evaluating multifactorial interventions in falls have reported variable outcomes. Given likely cultural, personal, lifestyle and health service differences in Asian countries, it is vital that individually-tailored multifaceted interventions are evaluated in an Asian population to determine applicability of these interventions in our setting. If successful, these approaches have the potential for widespread application in geriatric healthcare services, will reduce the projected escalation of falls and fall-related injuries, and improve the quality of life of our older community. Trial registration ISRCTN11674947 PMID:24951180
Systematic Review of Falls in Older Adults with Cancer
Wildes, Tanya M; Dua, Priya; Fowler, Susan A.; Miller, J. Philip; Carpenter, Christopher R.; Avidan, Michael S.; Stark, Susan
2014-01-01
Objectives lder adults frequently experience falls, at great cost to themselves and society. Older adults with cancer may be at greater risk for falls and have unique risk factors. Materials and Methods We undertook a systematic review of the available medical literature to examine the current evidence regarding factors associated with falls in older adults with cancer. PubMed, Embase, CINAHL, CENTRAL, DARE, Cochrane Database of Systematic Reviews and clinical trials.gov were searched using standardized terms for concepts of oncology/cancer, people 60 and older, screening, falls and diagnosis. Eligible studies included cohort or case-control studies or clinical trials in which all patients, or a subgroup of patients, had a diagnosis of cancer and in which falls were either the primary or secondary outcome. Results We identified 31 studies that met our inclusion criteria. Several studies suggest that falls are more common in older adults with a diagnosis of cancer than those without. Among the 11 studies that explored factors associated with outpatient falls, some risk factors for falls established in the general population were also associated with falls in older adults with cancer, including dependence in activities of daily living and prior falls. Other factors associated with falls in a general population, such as age, polypharmacy and opioid use, were not predictive of falls among oncology populations. Falls among older adults with cancer in the inpatient setting were associated with established risk factors for falls in people without cancer, but also with factors unique to an oncology population, such as brain metastases. Conclusions Falls in older adults with cancer are more common than in the general population, and are associated with risk factors unique to people with cancer. Further study is needed to establish methods of screening older adults with cancer for fall risk and ultimately implement interventions to reduce their risk of falls. Identifying which older adults with cancer are at greater risk for falls is a requisite step to ultimately intervene and prevent falls in this vulnerable population. PMID:25454770
Evaluation of Predictive Factors Influencing Community Reintegration in Adult Patients with Stroke
Olawale, Olajide Ayinla; Usman, Jibrin Sammani; Oke, Kayode Israel; Osundiya, Oladunni Caroline
2018-01-01
Objectives: Patients with stroke are faced with gait, balance, and fall difficulties which could impact on their community reintegration. In Nigeria, community reintegration after stroke has been understudied. The objective of this study was to evaluate the predictors of community reintegration in adult patients with stroke. Materials and Methods: Participants were 91 adult patients with stroke. Gait variables, balance self-efficacy, community balance/mobility, and fall self-efficacy were assessed using Rivermead Mobility Index, Activities-specific Balance Confidence Scale, Community Balance and Mobility Scale, and Falls Efficacy Scale-International respectively. Reintegration to Normal Living Index was used to assess satisfaction with community reintegration. Pearson Product-Moment Correlation Coefficient was used to determine the relationship between community reintegration and gait spatiotemporal variables, balance performance, and risk of fall. Multiple regression analysis was used to determine predictors of community reintegration (P ≤ 0.05). Results: There was significant positive relationship between community reintegration and cadence (r = 0.250, P = 0.017), functional mobility (r = 0.503, P = 0.001), balance self-efficacy (r = 0.608, P = 0.001), community balance/mobility (r = 0.586, P = 0.001), and duration of stroke (r = 0.220, P = 0.036). Stride time (r = −0.282, P = 0.073) and fall self-efficacy (r = 0.566, P = 0.001) were negatively correlated with community reintegration. Duration of stroke, balance self-efficacy, community balance/mobility, and fall self-efficacy (52.7% of the variance) were the significant predictors of community reintegration. Conclusion: Community reintegration is influenced by cadence, functional mobility, balance self-efficacy, community balance/mobility, and duration of stroke. Hence, improving balance and mobility during rehabilitation is important in enhancing community reintegration in patients with stroke. PMID:29456337
NASA Astrophysics Data System (ADS)
Hast, Michael; Howe, Christine
2013-07-01
Events involving motion in fall are differentiated psychologically from events involving horizontal motion. Do children associate motion down inclines more with motion along horizontals or more with motion in fall, or do they even treat it as an integration of the two? The question was raised over 20 years ago but never satisfactorily answered, so the principal aim of the reported research was to take matters forward. Children (n = 144) aged 5-11 years were assessed while predicting natural dynamic events along a horizontal, in fall and down an incline. They were required to make predictions of speed with heavy and light balls and under changes in incline heights. The results show that, consistent with previous work, faster horizontal motion was associated with the light ball across all ages, whereas faster fall was associated with the heavy ball. However, while the younger children predicted faster incline motion for the lighter ball, there was a shift in this conception towards older children predicting faster motion for the heavier ball. Understanding of how changes in incline height affect speed was generally good, with this aspect of the study helping to establish how children perceive diagonal dimensions. How supported horizontal motion and unsupported fall motion may affect children's changing understanding of incline motion is discussed, thus providing more complete insight into children's understanding of natural object motion than has been established so far.
Sundrić, Zvonko; Rajsić, Nenad; Lakocević, Milan; Nikolić-Djorić, Emilija
2010-01-01
Decrease of daily alertness is a common cause of accidents in the work place, especially traffic accidents. Therefore, an increasing interest exists to determine reliable indicators of a tendency to fall asleep involuntarily. To determine an optimal electroencephalographic (EEG) indicator of an involuntary tendency to fall asleep, we performed a study on neurologically healthy subjects, after one night of sleep deprivation. Total sleep deprivation was aimed at increasing daily sleepiness in healthy subjects, providing us with an opportunity to test different methods of evaluation. We applied a visual analogue scale for sleepiness (VASS), EEG registration with the specific test of alpha activity attenuation (TAA) in 87 healthy subjects. The test was perfomed in a standard way (sTAA) as well as in accordance with new modifications related to changes of EEG filter width in the range from 5 to 32 Hz (mTAA). After sleep deprivation, we observed involuntary falling asleep in 54 subjects. The comparison of VASS results showed no differences, contrary to a more objective TAA. Between two variants of TAA, the modified test provided us with a better prediction for subjects who would fall asleep involuntarily. The application of a more objective EEG test in evaluation of daily alertness represents the optimal method of testing. Modified TAA attracts special attention, offering a simple solution for reliable testing of decreased daily alertness in medical services related to professional aircraft personnel.
Medication fall risk in old hospitalized patients: a retrospective study.
Costa-Dias, Maria José; Oliveira, Alexandre Santos; Martins, Teresa; Araújo, Fátima; Santos, Ana Sofia; Moreira, Cristina Nogueira; José, Helena
2014-02-01
While the causes of falls in old hospitalized patients are multifactorial, medication has been considered as one of the most significant factors. Given the large impact that this phenomenon has on the lives of the elderly and organizations, it is important to explore such phenomenon in greater depth. The objective of this study was to explore the association between medication and falls and the recurrent falls (n≥2), and identify medication related risk for fall in hospitalized patients, in a large acute hospital. Retrospective and quantitative study from June 2008 to December 2010. The study was conducted in a private hospital for acute patients in Lisbon, Portugal. The study included a sample of 214 episodes of fall event notifications which occurred in 193 patients. The current study was conducted through the "face to face consensus" technique which emerged the treatment groups to investigate. Regarding the data analysis we used Student's t test, ANOVA and Odds Ratio. In the violation of the premises for the use of parametric statistics we used the Kruskal-Wallis test. To assess the fall risk, and the medication-related fall risk, we used the Morse Fall Risk Scale, and the Medication Fall Risk Score. Patients who received drugs from the therapy group of "Central Nervous System", are 10 times more likely to have fall risk (OR 9. 90, 95% CI 1.6-60.63). Association was found between falls (OR 6.09, 95% CI 1.30-28.54) and its recurrence (OR 3.32, 95% CI 1.61-6.85), among patients receiving haloperidol and receiving tramadol for recurrent falls (OR 3.10, 95% CI 1.59-6.07). In 34% of the patients the medication fall risk score was 6 or higher. This current study allowed identifying medication-related risk factors for falls, that nurses should consider when prescribing interventions to prevent falls and its recurrence, when patients are admitted to acute care hospitals. Copyright © 2014 Elsevier Ltd. All rights reserved.
6-PACK programme to decrease fall injuries in acute hospitals: cluster randomised controlled trial
Morello, Renata T; Wolfe, Rory; Brand, Caroline A; Haines, Terry P; Hill, Keith D; Brauer, Sandra G; Botti, Mari; Cumming, Robert G; Livingston, Patricia M; Sherrington, Catherine; Zavarsek, Silva; Lindley, Richard I; Kamar, Jeannette
2016-01-01
Objective To evaluate the effect of the 6-PACK programme on falls and fall injuries in acute wards. Design Cluster randomised controlled trial. Setting Six Australian hospitals. Participants All patients admitted to 24 acute wards during the trial period. Interventions Participating wards were randomly assigned to receive either the nurse led 6-PACK programme or usual care over 12 months. The 6-PACK programme included a fall risk tool and individualised use of one or more of six interventions: “falls alert” sign, supervision of patients in the bathroom, ensuring patients’ walking aids are within reach, a toileting regimen, use of a low-low bed, and use of a bed/chair alarm. Main outcome measures The co-primary outcomes were falls and fall injuries per 1000 occupied bed days. Results During the trial, 46 245 admissions to 16 medical and eight surgical wards occurred. As many people were admitted more than once, this represented 31 411 individual patients. Patients’ characteristics and length of stay were similar for intervention and control wards. Use of 6-PACK programme components was higher on intervention wards than on control wards (incidence rate ratio 3.05, 95% confidence interval 2.14 to 4.34; P<0.001). In all, 1831 falls and 613 fall injuries occurred, and the rates of falls (incidence rate ratio 1.04, 0.78 to 1.37; P=0.796) and fall injuries (0.96, 0.72 to 1.27; P=0.766) were similar in intervention and control wards. Conclusions Positive changes in falls prevention practice occurred following the introduction of the 6-PACK programme. However, no difference was seen in falls or fall injuries between groups. High quality evidence showing the effectiveness of falls prevention interventions in acute wards remains absent. Novel solutions to the problem of in-hospital falls are urgently needed. Trial registration Australian New Zealand Clinical Trials Registry ACTRN12611000332921. PMID:26813674
Horne, Maria; Speed, Shaun; Skelton, Dawn; Todd, Chris
2009-01-01
Background: strategies to prevent falls often recommend regular exercise. However, 40% of over 50s in the UK report less physical activity than is recommended. Even higher rates of sedentary behaviour have been reported among South Asian older adults. Objective: to identify salient beliefs that influence uptake and adherence to exercise for fall prevention among community-dwelling Caucasian and South Asian 60–70 year olds in the UK. Methods: we undertook an ethnographic study using participant observation, 15 focus groups (n = 87; mean age = 65.7 years) and 40 individual semi-structured interviews (mean age = 64.8 years). Data analysis used framework analysis. Results: young older adults do not acknowledge their fall risk and are generally not motivated to exercise to prevent falls. Those who had fallen are more likely to acknowledge risk of future falls. Whilst many of the beliefs about falls and exercise expressed were very similar between Caucasians and South Asians, there was a tendency for South Asians to express fatalistic beliefs more often. Conclusion: fall prevention should not be the focus of strategies to increase uptake and adherence to exercise. The wider benefits of exercise, leading to an active healthy lifestyle should be encouraged. PMID:19039019
Hayashi, Takahiro; Kondo, Katsunori; Suzuki, Kayo; Yamada, Minoru; Matsumoto, Daisuke
2014-01-01
Objective. Promoting participation in sport organizations may be a population strategy for preventing falls in older people. In this study, we examined whether participation in sport organizations is associated with fewer falls in older people even after adjusting for multiple individual and environmental factors. Methods. We used the Japan Gerontological Evaluation Study data of 90,610 people (31 municipalities) who were not eligible for public long-term care. Logistic regression analysis was performed, with multiple falls over the past year as the dependent variable and participation in a sport organization as the independent variable, controlling for 13 factors. These included individual factors related to falls, such as age and sex, and environmental factors such as population density of the habitable area. Results. A total of 6,391 subjects (7.1%) had a history of multiple falls. Despite controlling for 13 variables, those who participated in a sport organization at least once a week were approximately ≥20% less likely to fall than those who did not participate at all (once a week; odds ratio = 0.82 and 95% confidence interval = 0.72–0.95). Conclusion. Participation in a sport organization at least once per week might help prevent falls in the community-dwelling older people. PMID:24955360
SisFall: A Fall and Movement Dataset
Sucerquia, Angela; López, José David; Vargas-Bonilla, Jesús Francisco
2017-01-01
Research on fall and movement detection with wearable devices has witnessed promising growth. However, there are few publicly available datasets, all recorded with smartphones, which are insufficient for testing new proposals due to their absence of objective population, lack of performed activities, and limited information. Here, we present a dataset of falls and activities of daily living (ADLs) acquired with a self-developed device composed of two types of accelerometer and one gyroscope. It consists of 19 ADLs and 15 fall types performed by 23 young adults, 15 ADL types performed by 14 healthy and independent participants over 62 years old, and data from one participant of 60 years old that performed all ADLs and falls. These activities were selected based on a survey and a literature analysis. We test the dataset with widely used feature extraction and a simple to implement threshold based classification, achieving up to 96% of accuracy in fall detection. An individual activity analysis demonstrates that most errors coincide in a few number of activities where new approaches could be focused. Finally, validation tests with elderly people significantly reduced the fall detection performance of the tested features. This validates findings of other authors and encourages developing new strategies with this new dataset as the benchmark. PMID:28117691
SisFall: A Fall and Movement Dataset.
Sucerquia, Angela; López, José David; Vargas-Bonilla, Jesús Francisco
2017-01-20
Research on fall and movement detection with wearable devices has witnessed promising growth. However, there are few publicly available datasets, all recorded with smartphones, which are insufficient for testing new proposals due to their absence of objective population, lack of performed activities, and limited information. Here, we present a dataset of falls and activities of daily living (ADLs) acquired with a self-developed device composed of two types of accelerometer and one gyroscope. It consists of 19 ADLs and 15 fall types performed by 23 young adults, 15 ADL types performed by 14 healthy and independent participants over 62 years old, and data from one participant of 60 years old that performed all ADLs and falls. These activities were selected based on a survey and a literature analysis. We test the dataset with widely used feature extraction and a simple to implement threshold based classification, achieving up to 96% of accuracy in fall detection. An individual activity analysis demonstrates that most errors coincide in a few number of activities where new approaches could be focused. Finally, validation tests with elderly people significantly reduced the fall detection performance of the tested features. This validates findings of other authors and encourages developing new strategies with this new dataset as the benchmark.
RelFinder: Revealing Relationships in RDF Knowledge Bases
NASA Astrophysics Data System (ADS)
Heim, Philipp; Hellmann, Sebastian; Lehmann, Jens; Lohmann, Steffen; Stegemann, Timo
The Semantic Web has recently seen a rise of large knowledge bases (such as DBpedia) that are freely accessible via SPARQL endpoints. The structured representation of the contained information opens up new possibilities in the way it can be accessed and queried. In this paper, we present an approach that extracts a graph covering relationships between two objects of interest. We show an interactive visualization of this graph that supports the systematic analysis of the found relationships by providing highlighting, previewing, and filtering features.
The epidemiology of slips, trips, and falls in a helicopter manufacturing plant.
Amandus, Harlan; Bell, Jennifer; Tiesman, Hope; Biddle, Elyce
2012-06-01
The purpose of this evaluation was to evaluate the causes and costs of slips, trips, and falls (STFs) in a helicopter manufacturing plant. STFs are a significant portion of the total industry injury burden. For this study, 4,070 helicopter plant workers who were employed from January 1, 2004, through February 28, 2008, were enrolled. Company records on workers' compensation claims, occupational health first report of injury, and payroll records on hours worked were collected. Cause and source of all injuries, including STFs, were coded for analysis. During the 4-year study period, there were 2,378 injuries and 226 STFs (46 falls [20%] to a lower level, 117 [52%] falls on the same level, 41 [18%] from loss of balance without a fall, and 22 [10%] from other events). Of the 226 STFs, 123 falls to the same level were caused by slippery substances (52), objects on floor (43), and surface hazards (28), and they cost $1,543,946. Falls to lower levels primarily involved access to stands to and from aircraft and falling off large machines. More than half of the STF injury claims likely could have been prevented by housekeeping and maintenance, and this cost saving could reasonably offset a considerable portion of the cost of prevention. Training and stand modifications could be considered to prevent falls from elevation from stands, machines, and aircraft. Recommendations for STF prevention are discussed.
Translation of an Object Using Phase-Controlled Sound Sources in Acoustic Levitation
NASA Astrophysics Data System (ADS)
Matsui, Takayasu; Ohdaira, Etsuzo; Masuzawa, Nobuyoshi; Ide, Masao
1995-05-01
Acoustic levitation is used for positioning materials in the development of new materials in space where there is no gravity. This technique is applicable to materials for which electromagnetic force cannot be used. If the levitation point of the materials can be controlled freely in this application, possibilities of new applications will be extended. In this paper we report on an experimental study on controlling the levitation point of the object in an acoustic levitation system. The system fabricated and tested in this study has two sound sources with vibrating plates facing each other. Translation of the object can be achieved by controlling the phase of the energizing electrical signal for one of the sound sources. It was found that the levitation point can be moved smoothly in proportion to the phase difference between the vibrating plates.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mueller, Robert
2003-09-01
Pacific Northwest National Laboratory conducted video-based boat surveys to identify fall chinook salmon (Oncorhynchus tshawytscha) spawning areas located in deep water (>1 m) downstream of Bonneville Dam in the fall of 2002. This report documents the number and extent of chinook salmon spawning near Ives and Pierce Islands of the Columbia River, and is the fourth in a series of reports prepared since 1999. The main objective of this study was to find deepwater spawning locations of fall chinook salmon in the main Columbia River channel, collect additional data on physical habitat parameters at spawning sites, and provide estimates ofmore » adult spawners in the surveyed area. The secondary objective was to document the occurrence of any chum salmon (O. keta) redds located in the deeper sections near below Hamilton Creek. There was a significant increase in the number of fall chinook salmon redds found in the locations surveyed during the 2002 surveys when compared to previous surveys by Pacific Northwest National Laboratory. A total of 192 redds were found in two general locations adjacent to Pierce Island (river km 228.5) encompassing an area of approximately 9.31 ha. Peak spawning activity, based on redd counts and live fish seen near redds, was on or near November 15, 2002. An estimated 1,768 fall chinook salmon redds at water depths exceeding {approx}1.m ({approx} 125 kcfs) were documented in 2002. This estimate is the expanded number based on the number of redds found within the pre-defined survey area. Fall chinook salmon redds were found at water depths from 0.9 to 8.5 m and were constructed in gravel to large cobble ranging in size from 4.83 to 13.4 cm in diameter. No chum salmon redds were found in areas surveyed during 2002, although several carcasses were found at the mouth of Woodward Creek and in the deeper sections below Hamilton Creek.« less
Charlton, Kimberly; Kumar, Saravana
2017-01-01
Objective Despite consistent evidence for the positive impact of contingency planning for falls in older people, implementation of plans often fail. This is likely due to lack of recognition and knowledge about perspectives of older people about contingency planning. The objective of this research was to explore the perspectives of older people living in the community about use of contingency planning for getting help quickly after a fall. Method A systematic literature search seeking qualitative research was conducted in April 2014, with no limit placed on date of publication. Medline, EMBASE, Ageline, CINAHL, HealthSource- Nursing/Academic Edition, AMED and Psych INFO databases were searched. Three main concepts were explored and linked using Boolean operators; older people, falls and contingency planning. The search was updated until February 2016 with no new articles found. After removal of duplicates, 562 articles were assessed against inclusion and exclusion criteria resulting in six studies for the meta-synthesis. These studies were critically appraised using the McMaster critical appraisal tool. Bespoke data extraction sheets were developed and a meta-synthesis approach was adopted to extract and synthesise findings. Findings Three themes of ‘a mix of attitudes’, ‘careful deliberations’ and ‘a source of anxiety’ were established. Perspectives of older people were on a continuum between regarding contingency plans as necessary and not necessary. Levels of engagement with the contingency planning process seemed associated with acceptance of their risk of falling and their familiarity with available contingency planning strategies. Conclusion Avoiding a long lie on the floor following a fall is imperative for older people in the community but there is a lack of knowledge about contingency planning for falls. This meta-synthesis provides new insights into this area of health service delivery and highlights that implementation of plans needs to be directed by the older people rather than the health professionals. PMID:28562596
Falling Short in HR Management
ERIC Educational Resources Information Center
Bastian, Jim
2009-01-01
A school district's strategic objectives typically include improving education outcomes of students, reducing costs, improving customer service and increasing productivity. While the language, emphasis and order will vary, it is difficult to imagine a district that does not strategically focus on these or related objectives. Most districts perform…
ERIC Educational Resources Information Center
VanDeman, Barry A.
1984-01-01
Presents ideas for collecting objects on the school grounds or in the surrounding neighborhood. Objects include feathers/fur, leaves, galls, seeds, shells, spiderwebs, and litter. Also presents procedures for making impressions of bark, leaves, fossils, flora, and shadows. All activities can be adopted for students in kindergarten through grade…
Gravitational acceleration as a cue for absolute size and distance?
NASA Technical Reports Server (NTRS)
Hecht, H.; Kaiser, M. K.; Banks, M. S.
1996-01-01
When an object's motion is influenced by gravity, as in the rise and fall of a thrown ball, the vertical component of acceleration is roughly constant at 9.8 m/sec2. In principle, an observer could use this information to estimate the absolute size and distance of the object (Saxberg, 1987a; Watson, Banks, von Hofsten, & Royden, 1992). In five experiments, we examined people's ability to utilize the size and distance information provided by gravitational acceleration. Observers viewed computer simulations of an object rising and falling on a trajectory aligned with the gravitational vector. The simulated objects were balls of different diameters presented across a wide range of simulated distances. Observers were asked to identify the ball that was presented and to estimate its distance. The results showed that observers were much more sensitive to average velocity than to the gravitational acceleration pattern. Likewise, verticality of the motion and visibility of the trajectory's apex had negligible effects on the accuracy of size and distance judgments.
Optical inspection system for cylindrical objects
Brenden, Byron B.; Peters, Timothy J.
1989-01-01
In the inspection of cylindrical objects, particularly O-rings, the object is translated through a field of view and a linear light trace is projected on its surface. An image of the light trace is projected on a mask, which has a size and shape corresponding to the size and shape which the image would have if the surface of the object were perfect. If there is a defect, light will pass the mask and be sensed by a detector positioned behind the mask. Preferably, two masks and associated detectors are used, one mask being convex to pass light when the light trace falls on a projection from the surface and the other concave, to pass light when the light trace falls on a depression in the surface. The light trace may be either dynamic, formed by a scanned laser beam, or static, formed by such a beam focussed by a cylindrical lens. Means are provided to automatically keep the illuminating receiving systems properly aligned.
Zurales, Katie; DeMott, Trina K.; Kim, Hogene; Allet, Lara; Ashton-Miller, James A.; Richardson, James K.
2015-01-01
Objective To determine which gait measures on smooth and uneven surfaces predict falls and fall-related injuries in older subjects with diabetic peripheral neuropathy (DPN). Design Twenty-seven subjects (12 women) with a spectrum of peripheral nerve function ranging from normal to moderately severe DPN walked on smooth and uneven surfaces, with gait parameters determined by optoelectronic kinematic techniques. Falls and injuries were then determined prospectively over the following year. Results Seventeen subjects (62.9%) fell and 12 (44.4%) sustained a fall-related injury. As compared to non-fallers, the subject group reporting any fall, as well as the subject group reporting fall-related injury, demonstrated decreased speed, greater step width (SW), shorter step length (SL) and greater step-width-to-step-length ratio (SW:SL) on both surfaces. Uneven surface SW:SL was the strongest predictor of falls (pseudo-R2 = 0.65; p = .012) and remained so with inclusion of other relevant variables into the model. Post-hoc analysis comparing injured with non-injured fallers showed no difference in any gait parameter. Conclusion SW:SL on an uneven surface is the strongest predictor of falls and injuries in older subjects with a spectrum of peripheral neurologic function. Given the relationship between SW:SL and efficiency, older neuropathic patients at increased fall risk appear to sacrifice efficiency for stability on uneven surfaces. PMID:26053187
2017-01-01
Abstract Objective: To analyse the metric properties of the Timed Get up and Go-Modified Version Test (TGUGM), in risk assessment of falls in a group of physically active women. Methods: A sample was constituted by 202 women over 55 years of age, were assessed through a crosssectional study. The TGUGM was applied to assess their fall risk. The test was analysed by comparison of the qualitative and quantitative information and by factor analysis. The development of a logistic regression model explained the risk of falls according to the test components. Results: The TGUGM was useful for assessing the risk of falls in the studied group. The test revealed two factors: the Get Up and the Gait with dual task. Less than twelve points in the evaluation or runtimes higher than 35 seconds was associated with high risk of falling. More than 35 seconds in the test indicated a risk fall probability greater than 0.50. Also, scores less than 12 points were associated with a delay of 7 seconds more in the execution of the test (p= 0.0016). Conclusions: Factor analysis of TGUGM revealed two dimensions that can be independent predictors of risk of falling: The Get up that explains between 64% and 87% of the risk of falling, and the Gait with dual task, that explains between 77% and 95% of risk of falling. PMID:28559642
Balance Confidence and Falls in Non-Demented Essential Tremor Patients: The Role of Cognition
Rao, Ashwini K.; Gilman, Arthur; Louis, Elan D.
2014-01-01
Objective To examine 1) the effect of cognitive ability on balance confidence and falls, 2) the relationship of balance confidence and falls with quantitative measures of gait, and 3) measures that predict falls, in people with Essential Tremor (ET). Design Cross-sectional study. Setting: General community. Participants One-hundred-eighty participants (132 people with ET and 48 controls). People with ET were divided into two groups based on the median score on the modified Mini Mental State Exam: ET-LCS vs. ET-HCS. Interventions Not applicable. Main Outcome Measures Activities of Balance Confidence-6 (ABC) scale and falls in the previous year. Results ET-LCS had lower ABC-6 scores and a greater number of falls than ET-HCS (p<0.05 for all measures) or controls (p<0.01 for all measures). Quantitative gait measures were significantly correlated with ABC-6 score and falls. Gait speed (p<0.007) and ABC-6 score (p<0.02) were significant predictors of falls. Receiver Operating Characteristic curve analysis revealed that gait speed < 0.9 m/s and ABC-6 score < 51% were associated with moderate sensitivity and specificity in identifying fallers. Conclusions People with ET with low cognitive scores have impaired gait, and report lower balance confidence, and higher number of falls than their counterparts with higher cognitive scores, and controls. We have identified assessments that are easily administered (gait speed and ABC-6 scale), and are associated with falls in ET. PMID:24769121
Yang, Yijian; van Schooten, Kimberley S; Sims-Gould, Joanie; McKay, Heather A; Feldman, Fabio; Robinovitch, Stephen N
2018-02-01
Falls are a major health concern for older adults. Understanding sex differences in fall circumstances may guide the design of fall management plans specifically to men and women. In this study, analyzed real-life falls captured on video to compare scenarios leading to falls between men and women in 2 long-term care (LTC) facilities. Prospective cohort study. A total of 529 participants residing in 2 LTC facilities in British Columbia, Canada. Between 2008 and 2016, we video-captured 1738 falls experienced by 231 men and 298 women (mean age = 83 ± 9 years). Each video was analyzed to determine the causes of imbalance and the activities at time of falling. Using generalized estimating equation models, we examined how fall circumstances associated with age, sex, and health status. Men were more likely than women to fall from loss of support with an external object (odds ratio 1.37; 95% confidence interval 1.08-1.73) and less likely to fall from tripping (0.72; 0.54-0.96). Men were more likely to fall while seated (1.42; 1.07-1.87) or while rising (1.49; 1.11-1.99), and less likely to fall while walking (0.61; 0.50-0.75). After adjusting for age and health status, sex remained significantly associated with loss of support and walking. Furthermore, regardless of sex, falls from loss of support were more common among individuals who were less independent in activities of daily living, who used more medications, and who used diuretic. Individuals with independent activities of daily living and intact cognition were more likely to fall while walking, but less likely to fall while seated or while rising. Our results elucidate differences between older men and women in the scenarios that lead to falls, to inform sex-specific fall prevention strategies in the LTC setting. Copyright © 2017 AMDA – The Society for Post-Acute and Long-Term Care Medicine. Published by Elsevier Inc. All rights reserved.
Connection between competence, usability, environment and risk of falls in elderly adults
Leiva-Caro, José Alex; Salazar-González, Bertha Cecilia; Gallegos-Cabriales, Esther Carlota; Gómez-Meza, Marco Vinicio; Hunter, Kathleen F.
2015-01-01
Objective: to determine connections between competence, usability, environment and risk of falls in elderly adults. Method: correlational descriptive study, 123 elderly adults, both male and female, aged 70 years and older were included. Data was collected via the Tinetti Scale, CESD-7 Scale, Montreal Cognitive Assessment, Usability Questionnaire on Housing and Housing Enabler; and sociodemographic and health background certificate data. For data analysis, descriptive and inferential statistics were used, multivariate linear and logistic regression models were adjusted. Results: 42.0% of the elderly adults had presented with falls, with a higher prevalence in women, and in the group of 70-75 years. The physical environment of the house, gait, and usability were set as risk factors for falls. A negative relationship between usability and depressive symptoms, cognitive health, balance, gait, the social and physical environment was found, p <0.05; and a strong positive correlation between walking and balance, p <0.05. Conclusion: this study helps to better understand the phenomenon of falling, to find a connection between usability with the risk of falls, and other variables. PMID:26626006
Gottås, A; Øiestad, E L; Boix, F; Vindenes, V; Ripel, Å; Thaulow, C H; Mørland, J
2013-01-01
BACKGROUND AND PURPOSE Heroin, with low affinity for μ-opioid receptors, has been considered to act as a prodrug. In order to study the pharmacokinetics of heroin and its active metabolites after i.v. administration, we gave a bolus injection of heroin to rats and measured the concentration of heroin and its metabolites in blood and brain extracellular fluid (ECF). EXPERIMENTAL APPROACH After an i.v. bolus injection of heroin to freely moving Sprague–Dawley rats, the concentrations of heroin and metabolites in blood samples from the vena jugularis and in microdialysis samples from striatal brain ECF were measured by ultraperformance LC-MS/MS. KEY RESULTS Heroin levels decreased very fast, both in blood and brain ECF, and could not be detected after 18 and 10 min respectively. 6-Monoacetylmorphine (6-MAM) increased very rapidly, reaching its maximal concentrations after 2.0 and 4.3 min, respectively, and falling thereafter. Morphine increased very slowly, reaching its maximal levels, which were six times lower than the highest 6-MAM concentrations, after 12.6 and 21.3 min, with a very slow decline during the rest of the experiment and only surpassing 6-MAM levels at least 30 min after injection. CONCLUSIONS AND IMPLICATIONS After an i.v. heroin injection, 6-MAM was the predominant opioid present shortly after injection and during the first 30 min, not only in the blood but also in rat brain ECF. 6-MAM might therefore mediate most of the effects observed shortly after heroin intake, and this finding questions the general assumption that morphine is the main and most important metabolite of heroin. PMID:23865556
Predicting geriatric falls following an episode of emergency department care: a systematic review.
Carpenter, Christopher R; Avidan, Michael S; Wildes, Tanya; Stark, Susan; Fowler, Susan A; Lo, Alexander X
2014-10-01
Falls are the leading cause of traumatic mortality in geriatric adults. Despite recent multispecialty guideline recommendations that advocate for proactive fall prevention protocols in the emergency department (ED), the ability of risk factors or risk stratification instruments to identify subsets of geriatric patients at increased risk for short-term falls is largely unexplored. This was a systematic review and meta-analysis of ED-based history, physical examination, and fall risk stratification instruments with the primary objective of providing a quantitative estimate for each risk factor's accuracy to predict future falls. A secondary objective was to quantify ED fall risk assessment test and treatment thresholds using derived estimates of sensitivity and specificity. A medical librarian and two emergency physicians (EPs) conducted a medical literature search of PUBMED, EMBASE, CINAHL, CENTRAL, DARE, the Cochrane Registry, and Clinical Trials. Unpublished research was located by a hand search of emergency medicine (EM) research abstracts from national meetings. Inclusion criteria for original studies included ED-based assessment of pre-ED or post-ED fall risk in patients 65 years and older with sufficient detail to reproduce contingency tables for meta-analysis. Original study authors were contacted for additional details when necessary. The Quality Assessment Tool for Diagnostic Accuracy Studies (QUADAS-2) was used to assess individual study quality for those studies that met inclusion criteria. When more than one qualitatively similar study assessed the same risk factor for falls at the same interval following an ED evaluation, then meta-analysis was performed using Meta-DiSc software. The primary outcomes were sensitivity, specificity, and likelihood ratios for fall risk factors or risk stratification instruments. Secondary outcomes included estimates of test and treatment thresholds using the Pauker method based on accuracy, screening risk, and the projected benefits or harms of fall prevention interventions in the ED. A total of 608 unique and potentially relevant studies were identified, but only three met our inclusion criteria. Two studies that included 660 patients assessed 29 risk factors and two risk stratification instruments for falls in geriatric patients in the 6 months following an ED evaluation, while one study of 107 patients assessed the risk of falls in the preceding 12 months. A self-report of depression was associated with the highest positive likelihood ratio (LR) of 6.55 (95% confidence interval [CI] = 1.41 to 30.48). Six fall predictors were identified in more than one study (past falls, living alone, use of walking aid, depression, cognitive deficit, and more than six medications) and meta-analysis was performed for these risk factors. One screening instrument was sufficiently accurate to identify a subset of geriatric ED patients at low risk for falls with a negative LR of 0.11 (95% CI = 0.06 to 0.20). The test threshold was 6.6% and the treatment threshold was 27.5%. This study demonstrates the paucity of evidence in the literature regarding ED-based screening for risk of future falls among older adults. The screening tools and individual characteristics identified in this study provide an evidentiary basis on which to develop screening protocols for geriatrics adults in the ED to reduce fall risk. © 2014 by the Society for Academic Emergency Medicine.
Doré, Adam L.; Golightly, Yvonne M.; Mercer, Vicki S.; Shi, Xiaoyan A.; Renner, Jordan B.; Jordan, Joanne M.; Nelson, Amanda E.
2014-01-01
Objective Knee and hip osteoarthritis (OA) are known risk factors for falls, but whether they together additionally contribute to falls risk is unknown. This study utilizes a biracial cohort of men and women to examine the influence of lower limb OA burden on the risk for future falls. Methods A longitudinal analysis was performed using data from 2 time points of a large cohort. The outcome of interest was falls at follow up. Covariates included age, sex, race, body mass index, a history of prior falls, symptomatic OA of the hip and/or knee, a history of neurologic or pulmonary diseases, and current use of narcotic medications. Symptomatic OA was defined as patient reported symptoms and radiographic evidence of OA in the same joint. Logistic regression analyses were used to determine associations between covariates and falls at follow-up. Results The odds of falling increased with an increasing number of lower limb symptomatic OA joints: those with 1 joint had 53% higher odds, those with 2 joints had 74% higher odds, those with 3–4 OA joints had 85% higher odds. When controlling for covariates, patients who had symptomatic knee or hip OA had an increased likelihood of falling (aOR 1.39 95% CI [1.02, 1.88]; aOR 1.60 95% CI [1.14, 2.24], respectively). Conclusions This study reveals the risk for falls increases with additional symptomatic OA lower limb joints and confirms that symptomatic hip and knee OA are important risk factors for falls. PMID:25331686
Fall attributions among middle-aged and older adults with multiple sclerosis.
Peterson, Elizabeth W; Ben Ari, Eynat; Asano, Miho; Finlayson, Marcia L
2013-05-01
To (1) explore the falls attributions of middle-aged and older adults with multiple sclerosis (MS); and (2) examine the personal, health, and MS-related factors associated with the 3 most common attributions. A cross-sectional, descriptive study using data collected through a telephone interview. Falls attributions were obtained through an open-ended question to elicit participants' stories about their most recent fall. Recruitment was done through a national volunteer MS registry. Community. People (N=354) who were ≥55 years of age were interviewed; 313 provided a falls story. Respondents were primarily married, community-dwelling women who had been living with MS for 21 years, on average. Not applicable. The 3 most common fall attributions were used as dependent variables to address the second research objective. A total of 14 falls attributions were identified. The most common were balance (41.5%), lower extremity malfunction (31%), and assistive technology (AT; 29.7%). Falls control was significantly associated with the balance attribution (odds ratio [OR]=.51; 95% confidence interval [CI], .29-.88), no variables were associated with lower extremity malfunction attribution, and use of multiple mobility devices was significantly associated with the AT attribution (OR=3.78; 95% CI, 2.09-6.85). Findings highlight the complex nature of falls among middle-aged and older adults with MS and point to the need for comprehensive fall prevention interventions for this population. Further investigation of the role that perceived control over falls plays in this population is warranted. Copyright © 2013 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
Differing approaches to falls and fracture prevention between Australia and Colombia
Gomez, Fernando; Curcio, Carmen Lucia; Suriyaarachchi, Pushpa; Demontiero, Oddom; Duque, Gustavo
2013-01-01
Falls and fractures are major causes of morbidity and mortality in older people. More importantly, previous falls and/or fractures are the most important predictors of further events. Therefore, secondary prevention programs for falls and fractures are highly needed. However, the question is whether a secondary prevention model should focus on falls prevention alone or should be implemented in combination with fracture prevention. By comparing a falls prevention clinic in Manizales (Colombia) versus a falls and fracture prevention clinic in Sydney (Australia), the objective was to identify similarities and differences between these two programs and to propose an integrated model of care for secondary prevention of fall and fractures. A comparative study of services was performed using an internationally agreed taxonomy. Service provision was compared against benchmarks set by the National Institute for Health and Clinical Excellence (NICE) and previous reports in the literature. Comparison included organization, administration, client characteristics, and interventions. Several similarities and a number of differences that could be easily unified into a single model are reported here. Similarities included population, a multidisciplinary team, and a multifactorial assessment and intervention. Differences were eligibility criteria, a bone health assessment component, and the therapeutic interventions most commonly used at each site. In Australia, bone health assessment is reinforced whereas in Colombia dizziness assessment and management is pivotal. The authors propose that falls clinic services should be operationally linked to osteoporosis services such as a “falls and fracture prevention clinic,” which would facilitate a comprehensive intervention to prevent falls and fractures in older persons. PMID:23378748
An alternative model of free fall
NASA Astrophysics Data System (ADS)
Lattery, Mark
2018-03-01
In Two World Systems (Galileo 1632/1661 Dialogues Concerning Two New Sciences (New York: Prometheus)), Galileo attempted to unify terrestrial and celestial motions using the Aristotelian principle of circularity. The result was a model of free fall that correctly predicts the linear increase of the velocity of an object released from rest near the surface of the Earth. This historical episode provides an opportunity to communicate the nature of science to students.
ERIC Educational Resources Information Center
Chan, James; Kingsley, Elizabeth
This report on the operation of the Cooperative Urban Teacher Education Program (CUTE) for the fall semester 1969 is divided into two parts. Part 1 examines the objective data in terms of the hypotheses: 1) On each of the measures taken during the semester, students participating in the program do not change. 2) On each of the measures taken,…
Self-attraction effect and correction on the T-1 absolute gravimeter
NASA Astrophysics Data System (ADS)
Li, Z.; Hu, H.; Wu, K.; Li, G.; Wang, G.; Wang, L. J.
2015-12-01
The self-attraction effect (SAE) in an absolute gravimeter is a kind of systematic error due to the gravitation of the instrument to the falling object. This effect depends on the mass distribution of the gravimeter, and is estimated to be a few microgals (1 μGal = 10-8 m s-2) for the FG5 gravimeter. In this paper, the SAE of a home-made T-1 absolute gravimeter is analyzed and calculated. Most of the stationary components, including the dropping chamber, the laser interferometer, the vibration isolation device and two tripods, are finely modelled, and the related SAEs are computed. In addition, the SAE of the co-falling carriage inside the dropping chamber is carefully calculated because the distance between the falling object and the co-falling carriage varies during the measurement. In order to get the correction of the SAE, two different methods are compared. One is to linearize the SAE curve, the other one is to calculate the perturbed trajectory. The results from these two methods agree with each other within 0.01 μGal. With an uncertainty analysis, the correction of the SAE of the T-1 gravimeter is estimated to be (-1.9 ± 0.1) μGal.
Traumatic brain injuries from work accidents: a retrospective study.
Salem, A M O; Jaumally, B A; Bayanzay, K; Khoury, K; Torkaman, A
2013-07-01
The United Arab Emirates is a rapidly developing country with recent expansion in construction and manufacturing. To investigate the occurrence and outcomes following occupational traumatic brain injury (TBI) requiring hospital admission. Records for all TBI cases admitted to an Abu Dhabi hospital between 2005 and 2009 were reviewed. Data on mechanisms of occupational injuries, Glasgow Coma Scale (GCS) on admission and Glasgow Outcome Scale (GOS) on follow-up, were analysed. Of 581 TBI cases reviewed, 56 (10%) cases were reported as occupational by either the patient or the informant accompanying the patient. All cases were male migrants, and 63% were aged 25-44. Falls accounted for 63% of cases, falling objects 34% and motor vehicle collisions 4%. Median GCS score was 13 for all cases. Median hospital stay was 7.5 days. Intensive care unit admission data were available in 47 cases, of which 34% (16) were admitted with a median stay of 5 days. GOS data were available in 95% (53) of cases, with good recovery in 81% cases, moderate-to-severe disability in 11% of cases and death in 8% (4) cases. Occupational TBI requiring hospitalization is most frequently due to falls and falling objects, with potentially grave consequences. This study further highlights the urgent need to implement preventative measures to improve construction worker safety.
Abbasnejad, Feridoon; Shoja, Mohammadali M; Agutter, Paul S; Alakbarli, Farid; Loukas, Marios; Shokouhi, Ghaffar; Khalili, Majid; Tubbs, R Shane
2012-11-01
Following the Mongolian invasion of the Middle East in the thirteenth century, a regional power called the Ilkhanid emerged and was ruled by the heirs of Temujin from Mongolia. Embracing present-day Iran, Iraq, Afghanistan, Azerbaijan, areas of Russia, Turkey, and Pakistan, and nearby Middle Eastern territories, the Ilkhanid state patronized medicine and various other professions. Centered in Tabriz (Tauris), a city in the northwest of present-day Iran, was a non-profit-making educational and medical complex founded by Grand Minister Rashid al-Din Fazlollah Hamadani. This paper reviews the literature regarding the rise and fall of the thirteenth century university and the Rabi Rashidi, emphasizing the structure of its medical school. The background training of Rashid al-Din and his keen interest in science turned this complex, Rabi Rashidi (literally meaning the Rashidi Quarters), into a cosmopolitan university that freely trained medical scholars nationally and internationally. The possibility that Rashid al-Din was inspired by university developments in Europe is discussed.
NASA Astrophysics Data System (ADS)
Liao, Chuan-Chieh; Hsiao, Wen-Wei; Lin, Ting-Yu; Lin, Chao-An
2015-06-01
Numerical investigations are carried out for the drafting, kissing and tumbling (DKT) phenomenon of two freely falling spheres within a long container by using an immersed-boundary method. The method is first validated with flows induced by a sphere settling under gravity in a small container for which experimental data are available. The hydrodynamic interactions of two spheres are then studied with different sizes and initial configurations. When a regular sphere is placed below the larger one, the duration of kissing decreases in pace with the increase in diameter ratio. On the other hand, the time duration of the kissing stage increases in tandem with the increase in diameter ratio as the large sphere is placed below the regular one, and there is no DKT interactions beyond threshold diameter ratio. Also, the gap between homogeneous spheres remains constant at the terminal velocity, whereas the gaps between the inhomogeneous spheres increase due to the differential terminal velocity.
Structure and screening in molecular and metallic hydrogen at high pressure
NASA Technical Reports Server (NTRS)
Wood, D. M.; Ashcroft, N. W.
1981-01-01
A variational wavefunction is used to express the (spin restricted) Hartree-Fock energy as reciprocal lattice sums for static lattice FCC monatomic hydrogen and diatomic Pa3 molecular hydrogen. In the monatomic phase the hydrogenic orbital range closely parallels the inverse Thomas-Fermi wavevector; the corresponding energy E has a minimum of -0.929 Ryd/electron at r sub s = 1.67. For the diatomic phase E(r sub s) is similar, but the constituent energies, screening, and bond length reflect a qualitative change in the nature of the solid at r sub s = 2.8. This change is interpreted in terms of a transition from protons as structural units (at high density) to weakly interacting models (at low density). Insensitivity of the total energy to a rapid fall in the bond length suggests association with the rotational transition where the rapid molecular orientations characteristic of high pressures disappear and the molecules rotate freely at low pressure.
Woolcott, J C; Khan, K M; Mitrovic, S; Anis, A H; Marra, C A
2012-05-01
We prospectively collected data on elderly fallers to estimate the total cost of a fall requiring an Emergency Department presentation. Using data collected on 102 falls, we found the average cost per fall causing an Emergency Department presentation of $11,408. When hospitalization was required, the average cost per fall was $29,363. For elderly persons, falls are a major source of mortality, morbidity, and disability. Previous Canadian cost estimates of seniors' falls were based upon administrative data that has been shown to underestimate the incidence of falls. Our objective was to use a labor-intensive, direct observation patient-tracking method to accurately estimate the total cost of falls among seniors who presented to a major urban Emergency Department (ED) in Canada. We prospectively collected data from seniors (>70 years) presenting to the Vancouver General Hospital ED after a fall. We excluded individuals who where cognitively impaired or unable to read/write English. Data were collected on the care provided including physician assessments/consultations, radiology and laboratory tests, ED/hospital time, rehabilitation facility time, and in-hospital procedures. Unit costs of health resources were taken from a fully allocated hospital cost model. Data were collected on 101 fall-related ED presentations. The most common diagnoses were fractures (n = 33) and lacerations (n = 11). The mean cost of a fall causing ED presentation was $11,408 (SD: $19,655). Thirty-eight fallers had injuries requiring hospital admission with an average total cost of $29,363 (SD: $22,661). Hip fractures cost $39,507 (SD: $17,932). Among the 62 individuals not admitted to the hospital, the average cost of their ED visit was $674 (SD: $429). Among the growing population of Canadian seniors, falls have substantial costs. With the cost of a fall-related hospitalization approaching $30,000, there is an increased need for fall prevention programs.
Greene, Barry R; Redmond, Stephen J; Caulfield, Brian
2017-05-01
Falls are the leading global cause of accidental death and disability in older adults and are the most common cause of injury and hospitalization. Accurate, early identification of patients at risk of falling, could lead to timely intervention and a reduction in the incidence of fall-related injury and associated costs. We report a statistical method for fall risk assessment using standard clinical fall risk factors (N = 748). We also report a means of improving this method by automatically combining it, with a fall risk assessment algorithm based on inertial sensor data and the timed-up-and-go test. Furthermore, we provide validation data on the sensor-based fall risk assessment method using a statistically independent dataset. Results obtained using cross-validation on a sample of 292 community dwelling older adults suggest that a combined clinical and sensor-based approach yields a classification accuracy of 76.0%, compared to either 73.6% for sensor-based assessment alone, or 68.8% for clinical risk factors alone. Increasing the cohort size by adding an additional 130 subjects from a separate recruitment wave (N = 422), and applying the same model building and validation method, resulted in a decrease in classification performance (68.5% for combined classifier, 66.8% for sensor data alone, and 58.5% for clinical data alone). This suggests that heterogeneity between cohorts may be a major challenge when attempting to develop fall risk assessment algorithms which generalize well. Independent validation of the sensor-based fall risk assessment algorithm on an independent cohort of 22 community dwelling older adults yielded a classification accuracy of 72.7%. Results suggest that the present method compares well to previously reported sensor-based fall risk assessment methods in assessing falls risk. Implementation of objective fall risk assessment methods on a large scale has the potential to improve quality of care and lead to a reduction in associated hospital costs, due to fewer admissions and reduced injuries due to falling.
Rojas-Fernandez, Carlos; Dadfar, Farzan; Wong, Andrea; Brown, Susan G
2015-10-14
Falls continue to be a problem for older people in long-term care (LTC) and retirement home (RH) settings and are associated with significant morbidity and health care use. Fall-risk increasing drugs (FRIDs) are known to increase fall risk and represent modifiable risk factors. There are limited data regarding the use of FRIDs in contemporary LTC and RH settings, and it has not been well documented to what extent medication regimens are reviewed and modified for those who have sustained falls. The objective of this study is to characterize medication related fall risk factors in LTC and RH residents and on-going use of medications known to increase fall risk. Retrospective chart review of residents aged >65 who sustained one or more falls living in LTC or RH settings. 105 residents who fell one or more times during 2009-2010 were identified with a mean age of 89 years, a mean of nine scheduled medications and seven diagnoses, and 83% were women. Residents in LTC were ostensibly at higher risk for falls relative to those in RH settings as suggested by higher proportion of residents with multiple falls, multiple comorbidities, comorbidities that increase fall risk and visual impairment. Post fall injuries were sustained by 42% of residents, and residents in RH sustained more injuries relative to LTC residents (47 vs 34%). Use of FRIDs such as benzodiazepines, antipsychotic, antidepressant and various antihypertensive drugs was common in the present sample. No medication regimen changes were noted in the 6-month post fall period. The present study documented common use FRIDs by LTC and RH residents with multiple falls. These potentially modifiable falls risk factors are not being adequately addressed in contemporary practice, demonstrating that there is much room for improvement with regards to the safe and appropriate use of medications in LTC and RH residents.
Baccaglini, Lorena
2016-01-01
Objectives Falls in the geriatric population are a major public health issue. With the anticipated aging of the population, falls are expected to increase nationally and globally. We estimated the prevalence and determinants of falls in adults aged ≥65 years and calculated the proportion of elderly who fell and made lifestyle changes as a result of professional recommendations. Methods We included adults aged ≥65 years from the 2011–2012 California Health Interview Survey (CHIS) and categorized them into two groups based on whether or not they had had at least two falls in the previous 12 months. We performed logistic regression analysis adjusted for the complex survey design to determine risk factors for falls and compare the odds of receiving professional recommendations among elderly with vs. without falls. Results Of an estimated 4.3 million eligible elderly participants in the CHIS (2011–2012), an estimated 527,340 (12.2%) fell multiple times in the previous 12 months. Of those, 204,890 (38.9%) were told how to avoid falls by a physician and 211,355 (40.1%) received medical treatment, although fewer than 41.0% had made related preventive changes to avoid future falls. Falls were associated with older age, less walking, and poorer physical or mental health. Non-Asians had higher odds of falling compared with Asians (adjusted odds ratio = 1.69, 95% confidence interval 1.16, 2.45). Most participants reported changing medications, home, or daily routines on their own initiative rather than after professional recommendations. Conclusion Patients with a history of falls did not consistently receive professional recommendations on fall prevention-related lifestyle or living condition changes. Given the high likelihood of a serious fall, future interventions should focus on involving primary care physicians in active preventive efforts before a fall occurs. PMID:26957668
Klenk, Jochen; Kerse, Ngaire; Rapp, Kilian; Becker, Clemens; Rothenbacher, Dietrich; Peter, Richard; Denkinger, Michael Dieter
2015-01-01
Objectives To investigate the relationship between physical activity and two measures of fall incidence in an elderly population using person-years as well as hours walked as denominators and to compare these two approaches. Design Prospective cohort study with one-year follow-up of falls using fall calendars. Physical activity was defined as walking duration and recorded at baseline over one week using a thigh-worn uni-axial accelerometer (activPAL; PAL Technologies, Glasgow, Scotland). Average daily physical activity was extracted from these data and categorized in low (0–59 min), medium (60–119 min) and high (120 min and more) activity. Setting The ActiFE Ulm study located in Ulm and adjacent regions in Southern Germany. Participants 1,214 community-dwelling older people (≥65 years, 56.4% men). Measurements Negative-binomial regression models were used to calculate fall rates and incidence rate ratios for each activity category each with using (1) person-years and (2) hours walked as denominators stratified by gender, age group, fall history, and walking speed. All analyses were adjusted either for gender, age, or both. Results No statistically significant association was seen between falls per person-year and average daily physical activity. However, when looking at falls per 100 hours walked, those who were low active sustained more falls per hours walked. The highest incidence rates of falls were seen in low-active persons with slow walking speed (0.57 (95% confidence interval (95% CI): 0.33 to 0.98) falls per 100 hours walked) or history of falls (0.60 (95% CI: 0.36 to 0.99) falls per 100 hours walked). Conclusion Falls per hours walked is a relevant and sensitive outcome measure. It complements the concept of incidence per person years, and gives an additional perspective on falls in community-dwelling older people. PMID:26058056
Falls, Cognitive Impairment, and Gait Performance: Results From the GOOD Initiative
Allali, Gilles; Launay, Cyrille P.; Blumen, Helena M.; Callisaya, Michele L.; De Cock, Anne-Marie; Kressig, Reto W.; Srikanth, Velandai; Steinmetz, Jean-Paul; Verghese, Joe; Beauchet, Olivier
2017-01-01
Objectives Falls are highly prevalent in individuals with cognitive decline. The complex relationship between falls and cognitive decline (including both subtype and severity of dementia) and the influence of gait disorders have not been studied. This study aimed to examine the association between the subtype (Alzheimer disease [AD] versus non-AD) and the severity (from preclinical to moderate dementia) of cognitive impairment and falls, and to establish an association between falls and gait parameters during the course of dementia. Design Multicenter cross-sectional study. Setting “Gait, cOgnitiOn & Decline” (GOOD) initiative. Participants A total of 2496 older adults (76.6 ± 7.6 years; 55.0% women) were included in this study (1161 cognitively healthy individuals [CHI], 529 patients with mild cognitive impairment [MCI], 456 patients with mild dementia, and 350 with moderate dementia) from 7 countries. Measurements Falls history was collected retrospectively at baseline in each study. Gait speed and stride time variability were recorded at usual walking pace with the GAITRite system. Results The prevalence of individuals who fall was 50% in AD and 64% in non-AD; whereas it was 25% in CHIs. Only mild and moderate non-AD dementia were associated with an increased risk for falls in comparison with CHI. Higher stride time variability was associated with falls in older adults without dementia (CHI and each MCI subgroup) and mild non-AD dementia, whereas lower gait speed was associated with falls in all participant groups, except in mild AD dementia. When gait speed was adjusted for, higher stride time variability was associated with falls only in CHIs (odds ratio 1.14; P = .012), but not in MCI or in patients with dementia. Conclusions These findings suggest that non-AD, but not AD dementia, is associated with increased falls in comparison with CHIs. The association between gait parameters and falls also differs across cognitive status, suggesting different mechanisms leading to falls in older individuals with dementia in comparison with CHIs who fall. PMID:27914848
Parachuting from fixed objects: descriptive study of 106 fatal events in BASE jumping 1981-2006.
Westman, A; Rosén, M; Berggren, P; Björnstig, U
2008-06-01
To analyse the characteristics of fatal incidents in fixed object sport parachuting (building, antenna, span, earth (BASE) jumping) and create a basis for prevention. Descriptive epidemiological study. Data on reported fatal injury events (n = 106) worldwide in 1981-2006 retrieved from the BASE fatality list. Human, equipment and environmental factors. Identification of typical fatal incident and injury mechanisms for each of the four fixed object types of BASE jumping (building, antenna, span, earth). Human factors included parachutist free fall instability (loss of body control before parachute deployment), free fall acrobatics and deployment failure by the parachutist. Equipment factors included pilot chute malfunction and parachute malfunction. In cliff jumping (BASE object type E), parachute opening towards the object jumped was the most frequent equipment factor. Environmental factors included poor visibility, strong or turbulent winds, cold and water. The overall annual fatality risk for all object types during the year 2002 was estimated at about one fatality per 60 participants. Participants in BASE jumping should target risk factors with training and technical interventions. The mechanisms described in this study should be used by rescue units to improve the management of incidents.
Childhood and adult mortality from unintentional falls in India
Jagnoor, Jagnoor; Suraweera, Wilson; Keay, Lisa; Ivers, Rebecca Q; Thakur, JS; Gururaj, Gopalkrishna
2011-01-01
Abstract Objective To estimate fall-related mortality by type of fall in India. Methods The authors analysed unintentional injury data from the ongoing Million Death Study from 2001–2003 using verbal autopsy and coding of all deaths in accordance with the International statistical classification of diseases and related health problems, tenth revision, in a nationally representative sample of 1.1 million homes throughout the country. Findings Falls accounted for 25% (2003/8023) of all deaths from unintentional injury and were the second leading cause of such deaths. An estimated 160 000 fall-related deaths occurred in India in 2005; of these, nearly 20 000 were in children aged 0–14 years. The unintentional-fall-related mortality rate (MR) per 100 000 population was 14.5 (99% confidence interval, CI: 13.7–15.4). Rates were similar for males and females at 14.9 (99% CI: 13.7–16.0) and 14.2 (99% CI: 13.1–15.4) per 100 000 population, respectively. People aged 70 years or older had the highest mortality rate from unintentional falls (MR: 271.2; 99% CI: 249.0–293.5), and the rate was higher among women (MR: 281; 99% CI: 249.7–311.3). Falls on the same level were the most common among older adults, whereas falls from heights were more common in younger age groups. Conclusion In India, unintentional falls are a major public health problem that disproportionately affects older women and children. The contexts in which these falls occur and the resulting morbidity and disability need to be better understood. In India there is an urgent need to develop, test and implement interventions aimed at preventing falls. PMID:22084511
Hauser, Robert A; Heritier, Stephane; Rowse, Gerald J; Hewitt, L Arthur; Isaacson, Stuart H
2016-01-01
Droxidopa is a prodrug of norepinephrine indicated for the treatment of orthostatic dizziness, lightheadedness, or the "feeling that you are about to black out" in adult patients with symptomatic neurogenic orthostatic hypotension caused by primary autonomic failure including Parkinson disease (PD). The objective of this study was to compare fall rates in PD patients with symptomatic neurogenic orthostatic hypotension randomized to droxidopa or placebo. Study NOH306 was a 10-week, phase 3, randomized, placebo-controlled, double-blind trial of droxidopa in PD patients with symptomatic neurogenic orthostatic hypotension that included assessments of falls as a key secondary end point. In this report, the principal analysis consisted of a comparison of the rate of patient-reported falls from randomization to end of study in droxidopa versus placebo groups. A total of 225 patients were randomized; 222 patients were included in the safety analyses, and 197 patients provided efficacy data and were included in the falls analyses. The 92 droxidopa patients reported 308 falls, and the 105 placebo patients reported 908 falls. In the droxidopa group, the fall rate was 0.4 falls per patient-week; in the placebo group, the rate was 1.05 falls per patient-week (prespecified Wilcoxon rank sum P = 0.704; post hoc Poisson-inverse Gaussian test P = 0.014), yielding a relative risk reduction of 77% using the Poisson-inverse Gaussian model. Fall-related injuries occurred in 16.7% of droxidopa-treated patients and 26.9% of placebo-treated patients. Treatment with droxidopa appears to reduce falls in PD patients with symptomatic neurogenic orthostatic hypotension, but this finding must be confirmed.
Intuitive Test Theory. CSE Report 631
ERIC Educational Resources Information Center
Braun, Henry I.; Mislevy, Robert J.
2004-01-01
Psychologist Andrea diSessa coined the term "phenomenological primitives", or p-prims, to talk about nonexperts' reasoning about physical situations. P-prims are primitive in the sense that they stand without significant explanatory substructure or explanation. Examples are "Heavy objects fall faster than light objects" and "Continuing force is…
Hars, Mélany; Audet, Marie-Claude; Herrmann, François; De Chassey, Jean; Rizzoli, René; Reny, Jean-Luc; Gold, Gabriel; Ferrari, Serge; Trombetti, Andrea
2018-05-01
Falls are common among older inpatients and remain a great challenge for hospitals. Despite the relevance of physical impairments to falls, the prognostic value of performance-based functional measures for in-hospital falls and injurious falls remains unknown. This study aimed to determine the predictive ability and accuracy of various functional tests administered at or close to admission in a geriatric hospital to identify in-hospital fallers and injurious fallers. In this prospective study, conducted in a geriatric hospital in Geneva, Switzerland, 807 inpatients (mean age 85.0 years) were subjected to a battery of functional tests administered by physiotherapists within 3 days (interquartile range 1 to 6) of admission, including Short Physical Performance Battery (SPPB), simplified Tinetti, and Timed Up and Go tests. Patients were prospectively followed up for falls and injurious falls until discharge using mandatory standardized incident report forms and electronic patients' records. During a median length of hospital stay of 23 days (interquartile range 14 to 36), 329 falls occurred in 189 (23.4%) patients, including 161 injurious falls of which 24 were serious. In-hospital fallers displayed significantly poorer functional performances at admission on all tests compared with non-fallers (p < 0.001 for all). In multivariate analysis controlling for age, sex, previous falls, and fall as cause of admission, poorer functional performances on all functional tests predicted in-hospital falls and injurious falls (p < 0.001 for all). The SPPB only significantly predicted serious injurious falls (adjusted odds ratio [OR] = 0.76; 95% confidence interval [CI] 0.60-0.96) and fractures (adjusted OR = 0.76; 95% CI 0.59-0.98). In conclusion, poor functional performances, as assessed by SPPB, are independent predictors of in-hospital falls, injurious falls, and fractures in patients admitted to a geriatric hospital. These findings should help to design preventive strategies for in-hospital falls and support the adoption of objective performance-based functional measures into routine hospital practice. © 2018 American Society for Bone and Mineral Research. © 2018 American Society for Bone and Mineral Research.
Image manipulation: Fraudulence in digital dental records: Study and review
Chowdhry, Aman; Sircar, Keya; Popli, Deepika Bablani; Tandon, Ankita
2014-01-01
Introduction: In present-day times, freely available software allows dentists to tweak their digital records as never before. But, there is a fine line between acceptable enhancements and scientific delinquency. Aims and Objective: To manipulate digital images (used in forensic dentistry) of casts, lip prints, and bite marks in order to highlight tampering techniques and methods of detecting and preventing manipulation of digital images. Materials and Methods: Digital image records of forensic data (casts, lip prints, and bite marks photographed using Samsung Techwin L77 digital camera) were manipulated using freely available software. Results: Fake digital images can be created either by merging two or more digital images, or by altering an existing image. Discussion and Conclusion: Retouched digital images can be used for fraudulent purposes in forensic investigations. However, tools are available to detect such digital frauds, which are extremely difficult to assess visually. Thus, all digital content should mandatorily have attached metadata and preferably watermarking in order to avert their malicious re-use. Also, computer alertness, especially about imaging software's, should be promoted among forensic odontologists/dental professionals. PMID:24696587
Cause and Effect of Feedback: Multiphase Gas in Cluster Cores Heated by AGN Jets
NASA Astrophysics Data System (ADS)
Gaspari, M.; Ruszkowski, M.; Sharma, P.
2012-02-01
Multiwavelength data indicate that the X-ray-emitting plasma in the cores of galaxy clusters is not cooling catastrophically. To a large extent, cooling is offset by heating due to active galactic nuclei (AGNs) via jets. The cool-core clusters, with cooler/denser plasmas, show multiphase gas and signs of some cooling in their cores. These observations suggest that the cool core is locally thermally unstable while maintaining global thermal equilibrium. Using high-resolution, three-dimensional simulations we study the formation of multiphase gas in cluster cores heated by collimated bipolar AGN jets. Our key conclusion is that spatially extended multiphase filaments form only when the instantaneous ratio of the thermal instability and free-fall timescales (t TI/t ff) falls below a critical threshold of ≈10. When this happens, dense cold gas decouples from the hot intracluster medium (ICM) phase and generates inhomogeneous and spatially extended Hα filaments. These cold gas clumps and filaments "rain" down onto the central regions of the core, forming a cold rotating torus and in part feeding the supermassive black hole. Consequently, the self-regulated feedback enhances AGN heating and the core returns to a higher entropy level with t TI/t ff > 10. Eventually, the core reaches quasi-stable global thermal equilibrium, and cold filaments condense out of the hot ICM whenever t TI/t ff <~ 10. This occurs despite the fact that the energy from AGN jets is supplied to the core in a highly anisotropic fashion. The effective spatial redistribution of heat is enabled in part by the turbulent motions in the wake of freely falling cold filaments. Increased AGN activity can locally reverse the cold gas flow, launching cold filamentary gas away from the cluster center. Our criterion for the condensation of spatially extended cold gas is in agreement with observations and previous idealized simulations.
Harte, Richard; Hall, Tony; Glynn, Liam; Rodríguez-Molinero, Alejandro; Scharf, Thomas; ÓLaighin, Gearóid
2018-01-01
Background Each year, millions of older adults fall, with more than 1 out of 4 older people experiencing a fall annually, thereby causing a major social and economic impact. Falling once doubles one’s chances of falling again, making fall prediction an important aspect of preventative strategies. In this study, 22 older adults aged between 65 and 85 years were trained in the use of a smartphone-based fall prediction system. The system is designed to continuously assess fall risk by measuring various gait and balance parameters using a smart insole and smartphone, and is also designed to detect falls. The use case of the fall prediction system in question required the users to interact with the smartphone via an app for device syncing, data uploads, and checking system status. Objective The objective of this study was to observe the effect that basic smartphone training could have on the user experience of a group that is not technically proficient with smartphones when using a new connected health system. It was expected that even short rudimentary training could have a large effect on user experience and therefore increase the chances of the group accepting the new technology. Methods All participants received training on how to use the system smartphone app; half of the participants (training group) also received extra training on how to use basic functions of the smartphone, such as making calls and sending text messages, whereas the other half did not receive this extra training (no extra training group). Comparison of training group and no extra training group was carried out using metrics such as satisfaction rating, time taken to complete tasks, cues required to complete tasks, and errors made during tasks. Results The training group fared better in the first 3 days of using the system. There were significant recorded differences in number of cues required and errors committed between the two groups. By the fourth and fifth day of use, both groups were performing at the same level when using the system. Conclusions Supplementary basic smartphone training may be critical in trials where a smartphone app–based system for health intervention purposes is being introduced to a population that is not proficient with technology. This training could prevent early technology rejection and increase the engagement of older participants and their overall user experience with the system. PMID:29699969
Lomber, S G; Payne, B R; Cornwell, P
1996-01-01
Extrastriate visual cortex of the ventral-posterior suprasylvian gyrus (vPS cortex) of freely behaving cats was reversibly deactivated with cooling to determine its role in performance on a battery of simple or masked two-dimensional pattern discriminations, and three-dimensional object discriminations. Deactivation of vPS cortex by cooling profoundly impaired the ability of the cats to recall the difference between all previously learned pattern and object discriminations. However, the cats' ability to learn or relearn pattern and object discriminations while vPS was deactivated depended upon the nature of the pattern or object and the cats' prior level of exposure to them. During cooling of vPS cortex, the cats could neither learn the novel object discriminations nor relearn a highly familiar masked or partially occluded pattern discrimination, although they could relearn both the highly familiar object and simple pattern discriminations. These cooling-induced deficits resemble those induced by cooling of the topologically equivalent inferotemporal cortex of monkeys and provides evidence that the equivalent regions contribute to visual processing in similar ways. Images Fig. 1 Fig. 3 PMID:8643686
Klemp, Kerstin; Zwart, Dorien; Hansen, Jørgen; Hellebek, Torben; Luettel, Dagmar; Verstappen, Wim; Beyer, Martin; Gerlach, Ferdin M.; Hoffmann, Barbara; Esmail, Aneez
2015-01-01
Background: Incident reporting is widely used in both patient safety improvement programmes, and in research on patient safety. Objective: To identify the key requirements for incident reporting systems in primary care; to develop an Internet-based incident reporting and learning system for primary care. Methods: A literature review looking at the purpose, design and requirements of an incident reporting system (IRS) was used to update an existing incident reporting system, widely used in Germany. Then, an international expert panel with knowledge on IRS developed the criteria for the design of a new web-based incident reporting system for European primary care. A small demonstration project was used to create a web-based reporting system, to be made freely available for practitioners and researchers. The expert group compiled recommendations regarding the desirable features of an incident reporting system for European primary care. These features covered the purpose of reporting, who should be involved in reporting, the mode of reporting, design considerations, feedback mechanisms and preconditions necessary for the implementation of an IRS. Results: A freely available web-based reporting form was developed, based on these criteria. It can be modified for local contexts. Practitioners and researchers can use this system as a means of recording patient safety incidents in their locality and use it as a basis for learning from errors. Conclusion: The LINNEAUS collaboration has provided a freely available incident reporting system that can be modified for a local context and used throughout Europe. PMID:26339835
Workers' compensation experience of North Carolina residential construction workers, 1986-1994.
Dement, J M; Lipscomb, H
1999-02-01
A total of 31,113 workers' compensation claims among 7,400 North Carolina Homebuilders Association (NCHA) members and their subcontractors for the period 1986-1994 were analyzed to calculate workers' compensation claim incidence density rates. For the 7 years studied, the average rate (cases/200,000 work hours) for all claims was 16.40 and the rate for medical or lost time cases was 10.78. Highest rates for cases involving medical costs or paid lost time by mechanism of injury were observed for being struck by an object (3.1), lifting/movement (1.97), falls from a different level (1.13), striking against an object (0.87), and falls on the same level (0.46). Rates by mechanism of injury were highest for muscle strains (2.34), wounds/punctures (2.33), bruises/contusions (1.24), fractures/dislocations (0.98), and injuries to the eyes (0.81). Among medical cost or lost work time cases, body parts with highest injury rates were back/shoulders (1.99), fingers (1.31), leg/knee (1.00), hand/wrist (1.00), foot/ankle (0.86), and eyes (0.82). Injury rates were found to vary substantially among the residential construction trades. For more serious injuries involving medical costs greater than $2,000 or any lost work time, rates were highest for welders and cutters (28.1), insulators (24.3), roofers (19.4), and carpenters (15.3). The same general trends by trade were observed for cases involving paid lost time except that roofers were highest, with a rate of 9.1, followed by insulators (8.5), welders and cutters (5.8), and carpenters (5.8). Rates of falls from a different level resulting in medical costs or lost work time were highest for roofers (5.54), insulators (3.53), carpenters (2.05), and drywall installers (1.99). Descriptive information for falls from a different level resulting in paid lost time during 1993-1994 (n = 219) were reviewed to better determine the causes and circumstances of injuries. Falls from a roof accounted for 25.4 percent of the cases followed by falls involving scaffolds (23.9%) and ladders (20.6%), and falls from ceiling joists, floor joists, or framing (14.8%). Twenty-six work-related deaths occurred with vehicle accidents (n = 6) being the major known cause of death, followed by falls (n = 3), being struck by an object (n = 3), electric shock (n = 2), and contact with energy or chemicals (n = 2). Consistent with other analyses of workers' compensation data, chronic occupational diseases are not well captured in the workers' compensation claims among home builders; therefore, a companion study has examined mortality patterns among North Carolina construction workers.
Pohl, Petra; Sandlund, Marlene; Ahlgren, Christina; Bergvall-Kåreborn, Birgitta; Lundin-Olsson, Lillemor; Wikman, Anita Melander
2015-01-01
Introduction Daily life requires frequent estimations of the risk of falling and the ability to avoid a fall. The objective of this study was to explore older women’s and men’s understanding of fall risk and their experiences with safety precautions taken to prevent falls. Methods A qualitative study with focus group discussions was conducted. Eighteen community-dwelling people [10 women and 8 men] with and without a history of falls were purposively recruited. Participants were divided into two groups, and each group met four times. A participatory and appreciative action and reflection approach was used to guide the discussions. All discussions were audio recorded and transcribed verbatim. Data were analysed by qualitative content analysis, and categories were determined inductively. Findings Three categories describing the process of becoming aware of fall risks in everyday life were identified: 1] Facing various feelings, 2] Recognizing one’s fall risk, and 3] Taking precautions. Each category comprised several subcategories. The comprehensive theme derived from the categories was “Safety precautions through fall risk awareness”. Three strategies of ignoring [continuing a risky activity], gaining insight [realizing the danger in a certain situation], and anticipating [thinking ahead and acting in advance] were related to all choices of actions and could fluctuate in the same person in different contexts. Conclusions The fall risk awareness process might be initiated for various reasons and can involve different feelings and precautions as well as different strategies. This finding highlights that there are many possible channels to reach older people with information about fall risk and fall prevention, including the media and their peers. The findings offer a deeper understanding of older peoples’ conceptualizations about fall risk awareness and make an important contribution to the development and implementation of fall prevention programmes. PMID:25781181
Reduction in Fall Rate in Dementia Managed Care Through Video Incident Review: Pilot Study.
Bayen, Eleonore; Jacquemot, Julien; Netscher, George; Agrawal, Pulkit; Tabb Noyce, Lynn; Bayen, Alexandre
2017-10-17
Falls of individuals with dementia are frequent, dangerous, and costly. Early detection and access to the history of a fall is crucial for efficient care and secondary prevention in cognitively impaired individuals. However, most falls remain unwitnessed events. Furthermore, understanding why and how a fall occurred is a challenge. Video capture and secure transmission of real-world falls thus stands as a promising assistive tool. The objective of this study was to analyze how continuous video monitoring and review of falls of individuals with dementia can support better quality of care. A pilot observational study (July-September 2016) was carried out in a Californian memory care facility. Falls were video-captured (24×7), thanks to 43 wall-mounted cameras (deployed in all common areas and in 10 out of 40 private bedrooms of consenting residents and families). Video review was provided to facility staff, thanks to a customized mobile device app. The outcome measures were the count of residents' falls happening in the video-covered areas, the acceptability of video recording, the analysis of video review, and video replay possibilities for care practice. Over 3 months, 16 falls were video-captured. A drop in fall rate was observed in the last month of the study. Acceptability was good. Video review enabled screening for the severity of falls and fall-related injuries. Video replay enabled identifying cognitive-behavioral deficiencies and environmental circumstances contributing to the fall. This allowed for secondary prevention in high-risk multi-faller individuals and for updated facility care policies regarding a safer living environment for all residents. Video monitoring offers high potential to support conventional care in memory care facilities. ©Eleonore Bayen, Julien Jacquemot, George Netscher, Pulkit Agrawal, Lynn Tabb Noyce, Alexandre Bayen. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 17.10.2017.
BioSmalltalk: a pure object system and library for bioinformatics.
Morales, Hernán F; Giovambattista, Guillermo
2013-09-15
We have developed BioSmalltalk, a new environment system for pure object-oriented bioinformatics programming. Adaptive end-user programming systems tend to become more important for discovering biological knowledge, as is demonstrated by the emergence of open-source programming toolkits for bioinformatics in the past years. Our software is intended to bridge the gap between bioscientists and rapid software prototyping while preserving the possibility of scaling to whole-system biology applications. BioSmalltalk performs better in terms of execution time and memory usage than Biopython and BioPerl for some classical situations. BioSmalltalk is cross-platform and freely available (MIT license) through the Google Project Hosting at http://code.google.com/p/biosmalltalk hernan.morales@gmail.com Supplementary data are available at Bioinformatics online.
Terahertz radar cross section measurements.
Iwaszczuk, Krzysztof; Heiselberg, Henning; Jepsen, Peter Uhd
2010-12-06
We perform angle- and frequency-resolved radar cross section (RCS) measurements on objects at terahertz frequencies. Our RCS measurements are performed on a scale model aircraft of size 5-10 cm in polar and azimuthal configurations, and correspond closely to RCS measurements with conventional radar on full-size objects. The measurements are performed in a terahertz time-domain system with freely propagating terahertz pulses generated by tilted pulse front excitation of lithium niobate crystals and measured with sub-picosecond time resolution. The application of a time domain system provides ranging information and also allows for identification of scattering points such as weaponry attached to the aircraft. The shapes of the models and positions of reflecting parts are retrieved by the filtered back projection algorithm.
NASA Astrophysics Data System (ADS)
Xu, Jiuping; Li, Jun
2002-09-01
In this paper a class of stochastic multiple-objective programming problems with one quadratic, several linear objective functions and linear constraints has been introduced. The former model is transformed into a deterministic multiple-objective nonlinear programming model by means of the introduction of random variables' expectation. The reference direction approach is used to deal with linear objectives and results in a linear parametric optimization formula with a single linear objective function. This objective function is combined with the quadratic function using the weighted sums. The quadratic problem is transformed into a linear (parametric) complementary problem, the basic formula for the proposed approach. The sufficient and necessary conditions for (properly, weakly) efficient solutions and some construction characteristics of (weakly) efficient solution sets are obtained. An interactive algorithm is proposed based on reference direction and weighted sums. Varying the parameter vector on the right-hand side of the model, the DM can freely search the efficient frontier with the model. An extended portfolio selection model is formed when liquidity is considered as another objective to be optimized besides expectation and risk. The interactive approach is illustrated with a practical example.
There's no ball without noise: cats' prediction of an object from noise.
Takagi, Saho; Arahori, Minori; Chijiiwa, Hitomi; Tsuzuki, Mana; Hataji, Yuya; Fujita, Kazuo
2016-09-01
We used an expectancy violation procedure to ask whether cats could use a causal rule to infer the presence of an unseen object on hearing the noise it made inside a container and predict its appearance when the container was turned over. We presented cats with either an object dropping out of an opaque container or no object dropping out (turning-over phase) after producing either a rattling sound by shaking the container with the object inside, or no sound (shaking phase). The cats were then allowed to freely explore the experimental environment (exploration phase). The relation between the sound and the object matched with physical laws in half of the trials (congruent condition) and mismatched in the other half (incongruent condition). Inferring the presence of an unseen object from the noise was predicted to result in longer looking time in the incongruent condition. The prediction was supported by the cats' behavior during the turning-over phase. The results suggest that cats used a causal-logical understanding of auditory stimuli to predict the appearance of invisible objects. The ecology of cats' natural hunting style may favor the ability for inference on the basis of sounds.
Mobility, balance and falls in persons with multiple sclerosis.
Sosnoff, Jacob J; Socie, Michael J; Boes, Morgan K; Sandroff, Brian M; Pula, John H; Suh, Yoojin; Weikert, Madeline; Balantrapu, Swathi; Morrison, Steven; Motl, Robert W
2011-01-01
There is a lack of information concerning the relation between objective measures of gait and balance and fall history in persons with MS (PwMS). This investigation assessed the relation between demographic, clinical, mobility and balance metrics and falls history in persons with multiple sclerosis (MS). 52 ambulatory persons with MS (PwMS) participated in the investigation. All persons provided demographic information including fall history over the last 12 months. Disease status was assessed with Expanded Disability Status Scale (EDSS). Walking speed, coordination, endurance and postural control were quantified with a multidimensional mobility battery. Over 51% of the participants fell in the previous year with 79% of these people being suffering recurrent falls. Overall, fallers were older, had a greater prevalence of assistive devices use, worse disability, decreased walking endurance, and greater postural sway velocity with eyes closed compared to non-fallers. Additionally, fallers had greater impairment in cerebellar, sensory, pyramidal, and bladder/bowel subscales of the EDSS. The current observations suggest that PwMS who are older, more disabled, utilize an assistive device, have decreased walking coordination and endurance and have diminished balance have fallen in the previous year. This suggests that individuals who meet these criteria need to be carefully monitored for future falls. Future research is needed to determine a prospective model of falls specific to PwMS. Additionally, the utility of interventions aimed at reducing falls and fall risk in PwMS needs to be established.
Mobility, Balance and Falls in Persons with Multiple Sclerosis
Sosnoff, Jacob J.; Socie, Michael J.; Boes, Morgan K.; Sandroff, Brian M.; Pula, John H.; Suh, Yoojin; Weikert, Madeline; Balantrapu, Swathi; Morrison, Steven; Motl, Robert W.
2011-01-01
Background There is a lack of information concerning the relation between objective measures of gait and balance and fall history in persons with MS (PwMS). This investigation assessed the relation between demographic, clinical, mobility and balance metrics and falls history in persons with multiple sclerosis (MS). Methods 52 ambulatory persons with MS (PwMS) participated in the investigation. All persons provided demographic information including fall history over the last 12 months. Disease status was assessed with Expanded Disability Status Scale (EDSS). Walking speed, coordination, endurance and postural control were quantified with a multidimensional mobility battery. Results Over 51% of the participants fell in the previous year with 79% of these people being suffering recurrent falls. Overall, fallers were older, had a greater prevalence of assistive devices use, worse disability, decreased walking endurance, and greater postural sway velocity with eyes closed compared to non-fallers. Additionally, fallers had greater impairment in cerebellar, sensory, pyramidal, and bladder/bowel subscales of the EDSS. Conclusions The current observations suggest that PwMS who are older, more disabled, utilize an assistive device, have decreased walking coordination and endurance and have diminished balance have fallen in the previous year. This suggests that individuals who meet these criteria need to be carefully monitored for future falls. Future research is needed to determine a prospective model of falls specific to PwMS. Additionally, the utility of interventions aimed at reducing falls and fall risk in PwMS needs to be established. PMID:22132196
Influences of a Church-Based Intervention on Falls Risk Among Seniors.
Briggs, Morgan; Morzinski, Jeffrey A; Ellis, Julie
2017-08-01
Prior studies illustrate that community-based programs effectively decrease falls risk in older adults and that faith-based programs improve health behaviors. The literature is unclear whether faith-based initiatives reduce seniors' fall risks. To tackle this gap, a long-term partnership led by 10 urban churches, a nearby nursing school, and a medical school developed a study with 3 objectives: determine baseline health concerns associated with falls (eg, depression, polypharmacy), implement a nurse-led, faith-based health education initiative for community-dwelling African American seniors at-risk of hospitalization, and assess pre- to post -program fall frequency. The 100 Healthy, At-Risk Families study team implemented 8 monthly educational health sessions promoting self-care and social support. Community nurses led the 60- to 90-minute sessions at each of 10 churches. To collect study data, nurses interviewed enrolled seniors pre- and post-intervention. Descriptive and comparison statistics were analyzed in Excel and Statistical Package for Social Sciences. Senior data at baseline found high rates of polypharmacy and physical imbalance, and no significant depression or gaps in social support. There was not a statistically significant change pre- to post-program in fall frequency "in prior year." Study findings reveal insights about African American senior health and fall risks. Church settings may provide a protective, psychosocial buffer for seniors, while polypharmacy and mobility/balance concerns indicate need for continued attention to fall risks. No increase in pre- to post-program falls was encouraging.
Temporal association between hospitalization and rate of falls after discharge.
Mahoney, J E; Palta, M; Johnson, J; Jalaluddin, M; Gray, S; Park, S; Sager, M
2000-10-09
Evidence suggests that acute illness and hospitalization may increase the risk for falls. To evaluate the rate of falls, and associated risk factors, for 90 days following hospital discharge. We consecutively enrolled 311 patients, aged 65 years and older, discharged from the hospital after an acute medical illness and receiving home-nursing services. Patients were assessed within 5 days of discharge for prehospital and current functioning by self-report, and balance, vision, cognition, and delirium by objective measures. Patients were followed up weekly for 13 weeks for falls, injuries, and health care use. The rate of falls was significantly higher in the first 2 weeks after hospitalization (8.0 per 1000 person-days) compared with 3 months later (1.7 per 1000 person-days) (P =.002). Fall-related injuries accounted for 15% of all hospitalizations in the first month after discharge. Independent prehospital risk factors significantly associated with falls included dependency in activities of daily living, use of a standard walker, 2 or more falls, and more hospitalizations in the year prior. Posthospital risk factors included use of a tertiary amine tricyclic antidepressant, probable delirium, and poorer balance, while use of a cane was protective. The rate of falls is substantially increased in the first month after medical hospitalization, and is an important cause of injury and morbidity. Posthospital risk factors may be potentially modifiable. Efforts to assess and modify risk factors should be integral to the hospital and posthospital care of older adults (those aged >/=65 years).
Preclinical Alzheimer disease and risk of falls
Roe, Catherine M.; Grant, Elizabeth A.; Hollingsworth, Holly; Benzinger, Tammie L.; Fagan, Anne M.; Buckles, Virginia D.; Morris, John C.
2013-01-01
Objective: We determined the rate of falls among cognitively normal, community-dwelling older adults, some of whom had presumptive preclinical Alzheimer disease (AD) as detected by in vivo imaging of fibrillar amyloid plaques using Pittsburgh compound B (PiB) and PET and/or by assays of CSF to identify Aβ42, tau, and phosphorylated tau. Methods: We conducted a 12-month prospective cohort study to examine the cumulative incidence of falls. Participants were evaluated clinically and underwent PiB PET imaging and lumbar puncture. Falls were reported monthly using an individualized calendar journal returned by mail. A Cox proportional hazards model was used to test whether time to first fall was associated with each biomarker and the ratio of CSF tau/Aβ42 and CSF phosphorylated tau/Aβ42, after adjustment for common fall risk factors. Results: The sample (n = 125) was predominately female (62.4%) and white (96%) with a mean age of 74.4 years. When controlled for ability to perform activities of daily living, higher levels of PiB retention (hazard ratio = 2.95 [95% confidence interval 1.01–6.45], p = 0.05) and of CSF biomarker ratios (p < 0.001) were associated with a faster time to first fall. Conclusions: Presumptive preclinical AD is a risk factor for falls in older adults. This study suggests that subtle noncognitive changes that predispose older adults to falls are associated with AD and may precede detectable cognitive changes. PMID:23803314
Community Delivery of a Comprehensive Fall-Prevention Program in People with Multiple Sclerosis
Frankel, Debra; Tompkins, Sara A.; Cameron, Michelle
2016-01-01
Background: People with multiple sclerosis (MS) fall frequently. In 2011, the National Multiple Sclerosis Society launched a multifactorial fall-prevention group exercise and education program, Free From Falls (FFF), to prevent falls in MS. The objective of this study was to assess the impact of participation in the FFF program on balance, mobility, and falls in people with MS. Methods: This was a retrospective evaluation of assessments from community delivery of FFF. Changes in Activities-specific Balance Confidence scale scores, Berg Balance Scale scores, 8-foot Timed Up and Go performance, and falls were assessed. Results: A total of 134 participants completed the measures at the first and last FFF sessions, and 109 completed a 6-month follow-up assessment. Group mean scores on the Activities-specific Balance Confidence scale (F1,66 = 17.14, P < .05, η2 = 0.21), Berg Balance Scale (F1,68 = 23.39, P < .05, η2 = 0.26), and 8-foot Timed Up and Go (F1,79 = 4.83, P < .05, η2 = 0.06) all improved significantly from the first to the last session. At the 6-month follow-up, fewer falls were reported (χ2 [4, N = 239] = 10.56, P < .05, Phi = 0.21). Conclusions: These observational data suggest that the FFF group education and exercise program improves balance confidence, balance performance, and functional mobility and reduces falls in people with MS. PMID:26917997
Guo, Y F; Ma, W J; Zhang, Q J; Yu, M; Xiao, Y Z; Guo, X L; Zhu, Y L; Liu, F; Ruan, Y; Sun, S Y; Huang, Z Z; Zheng, Y; Wu, F
2018-03-10
Objective: To estimate the incidence and distribution characteristics of fall related injury in people aged ≥50 years in 8 provinces in China and related physiological, psychological and social risk factors. Methods: Cross-sectional data were collected from adults aged ≥50 years participating in the World Health Organization (WHO) study on global ageing and adult health (SAGE) round 1 in China. Two-level hierarchical logistic model was used to identify the related factors for fall-related injury. All the models were stratified by living area (urban/rural). Results: Estimated incidence of fall related injury (road traffic injury was not included) was 3.2 %. Ageing and multiple chronic conditions ( OR =2.55, 95 %CI : 1.41-4.64) was significantly associated with the incidence of fall related injury in urban area. In rural area, depression ( OR =4.33, 95 % CI : 2.52-7.42) and multiple chronic conditions ( OR =2.46, 95 %CI : 1.37-4.41) were associated with the incidence of fall related injury. Conclusions: This study estimated the incidence of fall related injury in adults aged ≥50 years in 8 provinces in China. A significant association between multiple chronic conditions and fall related injury were found in both urban and rural residents. Targeted measures should be taken for the prevention and control of chronic diseases in elderly population.
A retrospective review of fall risk factors in the bone marrow transplant inpatient service.
Vela, Cory M; Grate, Lisa M; McBride, Ali; Devine, Steven; Andritsos, Leslie A
2018-06-01
Purpose The purpose of this study was to compare medications and potential risk factors between patients who experienced a fall during hospitalization compared to those who did not fall while admitted to the Blood and Marrow Transplant inpatient setting at The James Cancer Hospital. Secondary objectives included evaluation of transplant-related disease states and medications in the post-transplant setting that may lead to an increased risk of falls, post-fall variables, and number of tests ordered after a fall. Methods This retrospective, case-control study matched patients in a 2:1 ratio of nonfallers to fallers. Data from The Ohio State University Wexner Medical Center (OSUWMC) reported fall events and patient electronic medical records were utilized. A total of 168 adult Blood and Marrow Transplant inpatients with a hematological malignancy diagnosis were evaluated from 1 January 2010 to 30 September 2012. Results Univariable and multivariable conditional logistic regression models were used to assess the relationship between potential predictor variables of interest and falls. Variables that were found to be significant predictors of falls from the univariable models include age group, incontinence, benzodiazepines, corticosteroids, anticonvulsants and antidepressants, and number of days status-post transplant. When considered for a multivariable model age group, corticosteroids, and a cancer diagnosis of leukemia were significant in the final model. Conclusion Recent medication utilization such as benzodiazepines, anticonvulsants, corticosteroids, and antidepressants placed patients at a higher risk of experiencing a fall. Other significant factors identified from a multivariable analysis found were patients older than age 65, patients with recent corticosteroid administration and a cancer diagnosis of leukemia.
Discriminant analysis for predictor of falls in stroke patients by using the Berg Balance Scale.
Maeda, Noriaki; Urabe, Yukio; Murakami, Masahito; Itotani, Keisuke; Kato, Junichi
2015-05-01
An observational study was carried out to estimate the strength of the relationships among balance, mobility and falls in hemiplegic stroke inpatients. The objective was to examine factors that may aid in the prediction of the likelihood of falls in stroke patients. A total of 53 stroke patients (30 male, 23 female) aged 67.0 ± 11.1 years were interviewed regarding their fall history. Physical performance was assessed using the Berg Balance Scale (BBS) and the Functional Independence Measure (FIM) scale. Variables that differed between fallers and non-fallers were identified, and a discriminant function analysis was carried out to determine the combination of variables that effectively predicted fall status. Of the 53 stroke patients, 19 were fallers. Compared with the non-fallers, the fallers scored low on the FIM, and differed with respect to age, time from stroke onset, length of hospital stay, Brunnstrom recovery stage and admission BBS score. Discriminant analysis for predicting falls in stroke patients showed that admission BBS score was significantly related to the likelihood of falls. Moreover, discriminant analysis showed that the use of a significant BBS score to classify fallers and non-fallers had an accuracy of 81.1%. The discriminating criterion between the two groups was a score of 31 points on the BBS. The results of this study suggest that BBS score is a strong predictor of falls in stroke patients. As balance is closely related to the risk of falls in hospitalised stroke patients, BBS might be useful in the prediction of falls.
Hill, Anne-Marie; McPhail, Steven M; Francis-Coad, Jacqueline; Waldron, Nicholas; Etherton-Beer, Christopher; Flicker, Leon; Ingram, Katharine; Haines, Terry P
2015-01-01
Objectives Falls are the most frequent adverse event reported in hospitals. Patient and staff education delivered by trained educators significantly reduced falls and injurious falls in an older rehabilitation population. The purpose of the study was to explore the educators’ perspectives of delivering the education and to conceptualise how the programme worked to prevent falls among older patients who received the education. Design A qualitative exploratory study. Methods Data were gathered from three sources: conducting a focus group and an interview (n=10 educators), written educator notes and reflective researcher field notes based on interactions with the educators during the primary study. The educators delivered the programme on eight rehabilitation wards for periods of between 10 and 40 weeks. They provided older patients with individualised education to engage in falls prevention and provided staff with education to support patient actions. Data were thematically analysed and presented using a conceptual framework. Results Falls prevention education led to mutual understanding between staff and patients which assisted patients to engage in falls prevention behaviours. Mutual understanding was derived from the following observations: the educators perceived that they could facilitate an effective three-way interaction between staff actions, patient actions and the ward environment which led to behaviour change on the wards. This included engaging with staff and patients, and assisting them to reconcile differing perspectives about falls prevention behaviours. Conclusions Individualised falls prevention education effectively provides patients who receive it with the capability and motivation to develop and undertake behavioural strategies that reduce their falls, if supported by staff and the ward environment. PMID:26656027
Gell, Nancy M.; Wallace, Robert B.; LaCroix, Andrea Z.; Mroz, Tracy M.; Patel, Kushang V.
2015-01-01
OBJECTIVES To examine mobility device use prevalence among community-dwelling older adults in the U.S. and to investigate the incidence of falls and worry about falling by the type and number of mobility devices used. DESIGN Analysis of cross-sectional and longitudinal data from the 2011–2012 National Health and Aging Trends Study SETTING In-person interviews in the homes of study participants PARTICIPANTS Nationally representative sample of Medicare beneficiaries(N=7609). MEASUREMENTS Participants were asked about mobility device use (e.g., canes, walkers, wheelchairs and scooters) in the last month, one-year fall history and worry about falling. RESULTS Twenty-four percent of adults age ≥65 reported mobility device use in 2011 and 9.3% reported using multiple devices within the last month. Mobility device use increased with advancing age and was associated with non-White race/ethnicity, female sex, lower education level, greater multi-morbidity, and obesity (all P-values < 0.001). Adjusting for demographic, health characteristics, and physical function, the incidence of falls and recurrent falls were not associated with the use of multiple devices or any one particular type of mobility device. Activity-limiting worry about falling was significantly higher in cane-only users, compared with non-users. CONCLUSION The percentage of older adults reporting mobility device use is higher compared to results from previous national surveys and multiple device use is common among those who use any device. Mobility device use is not associated with increased incidence of falls compared to non-device users. Cane-only users may compensate for worry about falling by limiting activity. PMID:25953070
Validity of Caregivers’ Reports on Head Trauma Due to Falls in Young Children Aged Less than 2 Years
Fujiwara, Takeo; Nagase, Hiroaki; Okuyama, Makiko; Hoshino, Takahiro; Aoki, Kazunori; Nagashima, Tastuya; Nakamura, Hajime
2010-01-01
Objective: The clinical presentations of head trauma due to falls among young children aged less than 2 years are controversial, particularly in Japan, as the history of trauma recounted by a caretaker is not always reliable. The purpose of this study was to assess the validity of caregiver’s reports on head trauma due to falls in young children aged less than 2 years in Japan. Methods: All patients <2 years of age presenting with head trauma resulting from a fall who were admitted to 3 children’s hospitals in Japan from January 2001 to December 2005 were retrospectively reviewed (N = 58). The clinical presentations were compared among groups categorized by the heights from which the patient fell (short (≤120 cm) or long (>120 cm)) and the surface on which the patient landed (carpet, tatami (Japanese mattress), hardwood floor, or concrete). Results: Patients who suffered short falls were more likely to present with subdural hemorrhage (SDH) than those who suffered long falls (74% and 40%, respectively, P = 0.027). More specifically, 62% of short falls showed SDH indicative of shaken baby syndrome (e.g. multilayer SDH). Neurological symptoms, cyanosis, and SDH were more commonly observed in patients who landed on carpeted or tatami surfaces than in those who landed on hardwood or concrete floors. Conclusions: Short falls and landing on soft surfaces resulted in the presentation of severer clinical symptoms than did long falls and landing on hard surfaces, suggesting that the validity of caretakers’ reports on infant or young children’s head trauma due to falls is low. Further research is warranted to investigate the cause of infant head trauma due to falls. PMID:23761991
Risk Factors Associated with Falls in Older Adults with Dementia: A Systematic Review
Fernando, Eresha; Fraser, Michelle; Hendriksen, Jane; Kim, Corey H.
2017-01-01
Purpose: People with dementia fall more often than cognitively healthy older adults, but their risk factors are not well understood. A review is needed to determine a fall risk profile for this population. The objective was to critically evaluate the literature and identify the factors associated with fall risk in older adults with dementia. Methods: Articles published between January 1988 and October 2014 in EMBASE, PubMed, PsycINFO, and CINAHL were searched. Inclusion criteria were participants aged 55 years or older with dementia or cognitive impairment, prospective cohort design, detailed fall definition, falls as the primary outcome, and multi-variable regression analysis. Two authors independently reviewed and extracted data on study characteristics, quality assessment, and outcomes. Adjusted risk estimates were extracted from the articles. Results: A total of 17 studies met the inclusion criteria. Risk factors were categorized into demographic, balance, gait, vision, functional status, medications, psychosocial, severity of dementia, and other. Risk factors varied with living setting and were not consistent across all studies within a setting. Conclusion: Falls in older adults with dementia are associated with multiple intrinsic and extrinsic risk factors, some shared with older adults in general and others unique to the disease. Risk factors vary between community- and institution-dwelling samples of adults with dementia or cognitive impairment. PMID:28539696
The equivalence principle comes to school—falling objects and other middle school investigations
NASA Astrophysics Data System (ADS)
Pendrill, Ann-Marie; Ekström, Peter; Hansson, Lena; Mars, Patrik; Ouattara, Lassana; Ryan, Ulrika
2014-07-01
Comparing two objects falling together is a small-scale version of Galileo’s classical experiment, demonstrating the equivalence between gravitational and inertial mass. We present here investigations by a group of ten-year-olds, who used iPads to record the drops. The movie recordings were essential in the follow-up discussions, enabling the students to compare the different situations and to discern situations where air resistance was essential and where it could be neglected. By considering a number of familiar situations and simple investigations that can be performed, e.g., on a playground, students may come closer to an appreciation of the deep significance of the non-influence of mass on motion under gravity.
An evaluation of hospital discharge records as a tool for serious work related injury surveillance.
Alamgir, H; Koehoorn, M; Ostry, A; Tompa, E; Demers, P
2006-04-01
To identify and describe work related serious injuries among sawmill workers in British Columbia, Canada using hospital discharge records, and compare the agreement and capturing patterns of the work related indicators available in the hospital discharge records. Hospital discharge records were extracted from 1989 to 1998 for a cohort of sawmill workers. Work related injuries were identified from these records using International Classification of Disease (ICD-9) external cause of injury codes, which have a fifth digit, and sometimes a fourth digit, indicating place of occurrence, and the responsibility of payment schedule, which identifies workers' compensation as being responsible for payment. The most frequent causes of work related hospitalisations were falls, machinery related, overexertion, struck against, cutting or piercing, and struck by falling objects. Almost all cases of machinery related, struck by falling object, and caught in or between injuries were found to be work related. Overall, there was good agreement between the two indicators (ICD-9 code and payment schedule) for identifying work relatedness of injury hospitalisations (kappa = 0.75, p < 0.01). There was better concordance between them for injuries, such as struck against, drowning/suffocation/foreign body, fire/flame/natural/environmental, and explosions/firearms/hot substance/electric current/radiation, and poor concordance for injuries, such as machinery related, struck by falling object, overexertion, cutting or piercing, and caught in or between. Hospital discharge records are collected for administrative reasons, and thus are readily available. Depending on the coding reliability and validity, hospital discharge records represent an alternative and independent source of information for serious work related injuries. The study findings support the use of hospital discharge records as a potential surveillance system for such injuries.
Cyclone: java-based querying and computing with Pathway/Genome databases.
Le Fèvre, François; Smidtas, Serge; Schächter, Vincent
2007-05-15
Cyclone aims at facilitating the use of BioCyc, a collection of Pathway/Genome Databases (PGDBs). Cyclone provides a fully extensible Java Object API to analyze and visualize these data. Cyclone can read and write PGDBs, and can write its own data in the CycloneML format. This format is automatically generated from the BioCyc ontology by Cyclone itself, ensuring continued compatibility. Cyclone objects can also be stored in a relational database CycloneDB. Queries can be written in SQL, and in an intuitive and concise object-oriented query language, Hibernate Query Language (HQL). In addition, Cyclone interfaces easily with Java software including the Eclipse IDE for HQL edition, the Jung API for graph algorithms or Cytoscape for graph visualization. Cyclone is freely available under an open source license at: http://sourceforge.net/projects/nemo-cyclone. For download and installation instructions, tutorials, use cases and examples, see http://nemo-cyclone.sourceforge.net.
Sri-On, Jiraporn; Tirrell, Gregory Philip; Kamsom, Anucha; Marill, Keith A; Shankar, Kalpana Narayan; Liu, Shan W
2018-03-25
The objectives were to examine whether responses to the Stopping Elderly Accidents, Death, and Injuries (STEADI) questions responses predicted adverse events after an older adult emergency department (ED) fall visits and to identify factors associated with such recurrent fall. We conducted a prospective study at two urban, teaching hospitals. We included patients aged ≥ 65 years who presented to the ED for an accidental fall. Data were gathered for fall-relevant comorbidities, high-risk medications for falls, and the responses to 12 questions from the STEADI guideline recommendation. Our outcomes were the number of 6-month adverse events that were defined as mortality, ED revisit, subsequent hospitalization, recurrent falls, and a composite outcome. There were 548 (86.3%) patients who completed follow-up and 243 (44.3%) patients experienced an adverse event after a fall within 6 months. In multivariate analysis, seven questions from the STEADI guideline predicted various outcomes. The question "Had previous fall" predicted recurrent falls (odds ratio [OR] = 2.45, 95% confidence interval [CI] = 1.52 to 3.97), the question "Feels unsteady when walking sometimes" (OR = 2.34, 95% CI = 1.44 to 3.81), and "Lost some feeling in their feet" predicted recurrent falls. In addition to recurrent falls risk, the supplemental questions "Use or have been advised to use a cane or walker," "Take medication that sometimes makes them feel light-headed or more tired than usual," "Take medication to help sleep or improve mood," and "Have to rush to a toilet" predicted other outcomes. A STEADI score of ≥4 did not predict adverse outcomes although seven individual questions from the STEADI guidelines were associated with increased adverse outcomes within 6 months. These may be organized into three categories (previous falls, physical activity, and high-risk medications) and may assist emergency physicians to evaluate and refer high-risk fall patients for a comprehensive falls evaluation. © 2018 by the Society for Academic Emergency Medicine.
Neyens, Jacques C L; Dijcks, Béatrice P J; van Haastregt, Jolanda C M; de Witte, Luc P; van den Heuvel, Wim J A; Crebolder, Harry F J M; Schols, Jos M G A
2006-03-21
Demented nursing home patients are at high risk for falls. Falls and associated injuries can have a considerable influence on the autonomy and quality of life of patients. The prevention of falls among demented patients is therefore an important issue. In order to intervene in an efficient way in this group of patients, it is important to systematically evaluate the fall risk profile of each individual patient so that for each patient tailor-made preventive measures can be taken. Therefore, the objective of the present study is to develop a feasible and evidence based multidisciplinary fall risk evaluation tool to be used for tailoring preventive interventions to the needs of individual demented patients. To develop this multidisciplinary fall risk evaluation tool we have chosen to combine scientific evidence on the one hand and experts' opinions on the other hand. Firstly, relevant risk factors for falling in elderly persons were gathered from the literature. Secondly, a group of Dutch experts in the field of falls and fall prevention in the elderly were consulted to judge the suitability of these risk factors for use in a multidisciplinary fall risk evaluation tool for demented nursing home patients. Thirdly, in order to generate a compact list of the most relevant risk factors for falling in demented elderly, all risk factors had to fulfill a set of criteria indicating their relevance for this specific target population. Lastly the final list of risk factors resulting from the above mentioned procedure was presented to the expert group. The members were also asked to give their opinion about the practical use of the tool. The multidisciplinary fall risk evaluation tool we developed includes the following items: previous falls, use of medication, locomotor functions, and (correct) choice and use of assistive and protective devices. The tool is developed for the multidisciplinary teams of the nursing homes. This evidence and practice based multidisciplinary fall risk evaluation tool targets the preventive interventions aimed to prevent falls and their negative consequences in demented nursing home patients.
A prototype supervised intelligent robot for helping astronauts
NASA Technical Reports Server (NTRS)
Erickson, J. D.; Grimm, K. A.; Pendleton, T. W.
1994-01-01
The development status is described of a prototype supervised intelligent robot for space application for purposes of (1) helping the crew of a spacecraft such as the Space Station with various tasks such as holding objects and retrieving/replacing tools and other objects from/into storage, and for purposes of (2) retrieving detached objects, such as equipment or crew, that have become separated from their spacecraft. In addition to this set of tasks in this low Earth orbiting spacecraft environment, it is argued that certain aspects of the technology can be viewed as generic in approach, thereby offering insight into intelligent robots for other tasks and environments. Also described are characterization results on the usable reduced gravity environment in an aircraft flying parabolas (to simulate weightlessness) and results on hardware performance there. These results show it is feasible to use that environment for evaluative testing of dexterous grasping based on real-time visual sensing of freely rotating and translating objects.
EMEN2: An Object Oriented Database and Electronic Lab Notebook
Rees, Ian; Langley, Ed; Chiu, Wah; Ludtke, Steven J.
2013-01-01
Transmission electron microscopy and associated methods such as single particle analysis, 2-D crystallography, helical reconstruction and tomography, are highly data-intensive experimental sciences, which also have substantial variability in experimental technique. Object-oriented databases present an attractive alternative to traditional relational databases for situations where the experiments themselves are continually evolving. We present EMEN2, an easy to use object-oriented database with a highly flexible infrastructure originally targeted for transmission electron microscopy and tomography, which has been extended to be adaptable for use in virtually any experimental science. It is a pure object-oriented database designed for easy adoption in diverse laboratory environments, and does not require professional database administration. It includes a full featured, dynamic web interface in addition to APIs for programmatic access. EMEN2 installations currently support roughly 800 scientists worldwide with over 1/2 million experimental records and over 20 TB of experimental data. The software is freely available with complete source. PMID:23360752
[Categorization in infancy: differentiation of global object classes].
Pauen, S
1996-01-01
Two studies tested whether preverbal children distinguish global categories (animal and furniture) on a conceptual basis. A total of 59 eleven-month-olds solved an object examination task. During habituation, infants freely explored different natural-looking toy models from the same category. In Study 1, the same series of four different examplars was presented twice. In Study 2, ten different exemplares were presented. In both cases, a significant habituation effect could be observed. When a perceptually new object of the same category was presented on the first test trial after habituation, a significant increase in examination time from the last habituation trial to the first test trial could be observed in Study 1. When a new object of the contrasting category was presented on the second test trial, examination times increased significantly from the first to the second test trial in both studies. These results support earlier findings suggesting that preverbal infants are able to distinguish global categories on a conceptual basis.
Grand, Laszlo; Ftomov, Sergiu; Timofeev, Igor
2012-01-01
Parallel electrophysiological recording and behavioral monitoring of freely moving animals is essential for a better understanding of the neural mechanisms underlying behavior. In this paper we describe a novel wireless recording technique, which is capable of synchronously recording in vivo multichannel electrophysiological (LFP, MUA, EOG, EMG) and activity data (accelerometer, video) from freely moving cats. The method is based on the integration of commercially available components into a simple monitoring system and is complete with accelerometers and the needed signal processing tools. LFP activities of freely moving group-housed cats were recorded from multiple intracortical areas and from the hippocampus. EMG, EOG, accelerometer and video were simultaneously acquired with LFP activities 24-h a day for 3 months. These recordings confirm the possibility of using our wireless method for 24-h long-term monitoring of neurophysiological and behavioral data of freely moving experimental animals such as cats, ferrets, rabbits and other large animals. PMID:23099345
Min, Seung-Nam; Kim, Jung-Yong; Parnianpour, Mohamad
2012-05-01
Work performed on scaffolds carries the risk of falling that disproportionately threatens the safety and health of novice construction workers. Hence, objective measures of the postural stability, cardiovascular stress, and subjective difficulty in maintaining postural balance were evaluated for four expert and four novice construction workers performing a manual task in a standing posture on a scaffold with and without safety handrails at two different elevation heights. Based on a multivariate analysis of variance, the experience, scaffold height, and presence of a handrail were found to significantly affect measures of the postural stability and cardiovascular stress. At a lower level of worker experience, a higher scaffold height, and in the absence of a handrail (which may correspond to higher risk of a fall), postural stability was significantly reduced, while cardiovascular stress and subjective difficulties in maintaining postural balance increased. We emphasize the importance of training and handrails for fall prevention at construction sites. Copyright © 2011 Elsevier Ltd and The Ergonomics Society. All rights reserved.
Local Dynamic Stability Associated with Load Carrying
Lockhart, Thurmon E
2013-01-01
Objectives Load carrying tasks are recognized as one of the primary occupational factors leading to slip and fall injuries. Nevertheless, the mechanisms associated with load carrying and walking stability remain illusive. The objective of the current study was to apply local dynamic stability measure in walking while carrying a load, and to investigate the possible adaptive gait stability changes. Methods Current study involved 25 young adults in a biomechanics research laboratory. One tri-axial accelerometer was used to measure three-dimensional low back acceleration during continuous treadmill walking. Local dynamic stability was quantified by the maximum Lyapunov exponent (maxLE) from a nonlinear dynamics approach. Results Long term maxLE was found to be significant higher under load condition than no-load condition in all three reference axes, indicating the declined local dynamic stability associated with load carrying. Conclusion Current study confirmed the sensitivity of local dynamic stability measure in load carrying situation. It was concluded that load carrying tasks were associated with declined local dynamic stability, which may result in increased risk of fall accident. This finding has implications in preventing fall accidents associated with occupational load carrying. PMID:23515183
Shankar, Kalpana N.; Liu, Shan W.; Ganz, David A.
2017-01-01
Introduction One third of older adults fall each year, and falls are costly to both the patient in terms of morbidity and mortality and to the health system. Given that falls are a preventable cause of injury, our objective was to understand the characteristics and trends of emergency department (ED) fall-related visits among older adults. We hypothesize that falls among older adults are increasing and examine potential factors associated with this rise, such as race, ethnicity, gender, insurance and geography. Methods We conducted a secondary analysis of data from the National Hospital Ambulatory Medical Care Survey (NHAMCS) to determine fall trends over time by examining changes in ED visit rates for falls in the United States between 2003 and 2010, detailing differences by gender, sociodemographic characteristics and geographic region. Results Between 2003 and 2010, the visit rate for falls and fall-related injuries among people age ≥ 65 increased from 60.4 (95% confidence interval [CI][51.9–68.8]) to 68.8 (95% CI [57.8–79.8]) per 1,000 population (p=0.03 for annual trend). Among subgroups, visits by patients aged 75–84 years increased from 56.2 to 82.1 per 1,000 (P <.01), visits by women increased from 67.4 to 81.3 (p = 0.04), visits by non-Hispanic Whites increased from 63.1 to 73.4 (p < 0.01), and visits in the South increased from 54.4 to 71.1 (p=0.03). Conclusion ED visit rates for falls are increasing over time. There is a national movement to increase falls awareness and prevention. EDs are in a unique position to engage patients on future fall prevention and should consider ways they can also partake in such initiatives in a manner that is feasible and appropriate for the ED setting. PMID:28874929
Air Resistance on Falling Balls and Balloons
NASA Astrophysics Data System (ADS)
Gluck, Paul
2003-03-01
Studying the effect of air resistance on falling objects in an introductory mechanics course has the merit of relevance to a considerable part of our everyday experience: Leaves, parachutes, raindrops, or soot particles do not keep accelerating as they fall. This topic has been discussed in this and other journals many times,1-7 ranging from theoretical treatments to various experimental investigations, mostly for coffee filters, depending on the apparatus at the disposal of the writers (video clips, graphic calculators, and so on). We report here a sequence of activities for our 11th-grade high school students dealing with this topic. The analysis of data emphasizes points that do not seem to have been done in previous articles.
NASA Astrophysics Data System (ADS)
Tian, Ruijun
Two typical unsteady fluid-structure interaction problems have been investigated in the present study. One of them was about actively plunged flexible hydrofoil; the other was about gravity-driven falling plates in water. Real-time velocity field and dynamic response on the moving objects were measured to study these unsteady and highly nonlinear problems. For a long time, scientists have believed that bird and insect flight benefits greatly from the flexibility and morphing facility of their wings via flapping motion. A significant advantage flexible wing models have over quasi-steady rigid wing models is a much higher lift generation capability. Both experimental and computational studies have shown that the leading and trailing edge vortexes (LEV and TEV) play a major role in the efficient generation of such unconventionally high lift force. In this study, two NACA0012 miniature hydrofoils, one flexible and the other rigid, were actively plunged at various frequencies in a viscous glycerol-water solution to study the influence of flexibility. Two-dimensional, phase-locked particle image velocimetry (PIV) measurements were conducted to investigate the temporal and spacial development of LEVs and TEVs. Simultaneous measurements of lift and thrust forces were recorded to reveal the relationship between hydrodynamic force and the evolution of the surrounding flow field. Results from the flexible hydrofoil were compared to those from the rigid one in order to quantitatively analyze the effects of flexibility. The second problem focused on fluid-structure interaction of gravity driven falling plates. Falling leaves and paper cards in air has drawn plenty of research interest in the past decades to investigate the interaction between the fluid flow and the falling object. In this research, time-resolved PIV were employed to experimentally visualize the flow field evolution around the gravity-driven falling plates. The plates were made of different materials with various geometric dimensions, in order to investigate the effects of non-dimensional parameters such as Reynolds number (Re) and dimensionless moment of inertia (I*). Within the range of relative high Reynolds numbers (Re > 500), three types of falling modes were observed: i.e., periodic fluttering, periodic tumbling and marginal chaotic motion. It was found that the nondimensional moment of inertia controlled the falling mode. The flow features through the falling path of the plate were characterized and compared with their corresponding kinematics. Based on theoretical analysis and experimental results, a semi-analytic model was developed to calculate the real-time hydrodynamic force and moment applied on falling plates. With this model, the falling trajectory of 2D plates with arbitrary material/dimension combinations can be predicted. The model yielded a good match for both the dynamic force simulation and trajectory prediction.
Kambhampati, Satya Samyukta; Singh, Vishal; Manikandan, M Sabarimalai; Ramkumar, Barathram
2015-08-01
In this Letter, the authors present a unified framework for fall event detection and classification using the cumulants extracted from the acceleration (ACC) signals acquired using a single waist-mounted triaxial accelerometer. The main objective of this Letter is to find suitable representative cumulants and classifiers in effectively detecting and classifying different types of fall and non-fall events. It was discovered that the first level of the proposed hierarchical decision tree algorithm implements fall detection using fifth-order cumulants and support vector machine (SVM) classifier. In the second level, the fall event classification algorithm uses the fifth-order cumulants and SVM. Finally, human activity classification is performed using the second-order cumulants and SVM. The detection and classification results are compared with those of the decision tree, naive Bayes, multilayer perceptron and SVM classifiers with different types of time-domain features including the second-, third-, fourth- and fifth-order cumulants and the signal magnitude vector and signal magnitude area. The experimental results demonstrate that the second- and fifth-order cumulant features and SVM classifier can achieve optimal detection and classification rates of above 95%, as well as the lowest false alarm rate of 1.03%.
Yardimci, Bulent; Aran, Sinan N.; Ozkaya, Ismail; Aksoy, Sevki M.; Demir, Tarik; Tezcan, Gulsen; Kaptanoglu, Aysegul Y.
2016-01-01
Objectives: To determine the relation among the risk of falls, geriatric assessment, and anthropometric measurements, including the mini mental state examination, geriatric depression scale, handgrip test, and key pinch test. Methods: This prospective study included 89 residents hospitalized between May 2014 and September 2015 in the geriatric care unit of the Istanbul Balikli Rum Hospital, Istanbul, Turkey. Patients were followed-up for one year, and their falls were recorded. Medical records of the included patients were retrieved and analyzed. Results: A total of 89 patients, comprising 37 men and 52 women with an average age of 75.8 ± 8.2 years were included in the study. The residents’ annual falling averages were 1.0 ± 1.5. The most significant factors were identified to be predicted muscle mass, skeletal muscle index, whole body bioimpedance, dominant arm muscle strength, dominant arm bioimpedance, and free fat mass. Conclusions: The mini mental test, geriatric depression scale and lawton-brody scale combined with the handgrip, 6-meters walking, and bioimpedance tests are favorable for detecting the risk of falls and recurrent falls in vulnerable elderly nursing home residents. PMID:27652361
Brown, Mary Jean; Jacobs, David E.
2011-01-01
Objectives. We examined the relationship between self-reported inadequate residential natural light and risk for depression or falls among adults aged 18 years or older. Methods. Generalized estimating equations were used to calculate the odds of depression or falls in participants with self-reported inadequate natural residential light vs. those reporting adequate light (n=6,017) using data from the World Health Organization's Large Analysis and Review of European Housing and Health Survey, a large cross-sectional study of housing and health in representative populations from eight European cities. Results. Participants reporting inadequate natural light in their dwellings were 1.4 times (95% confidence interval [CI] 1.2,1.7) as likely to report depression and 1.5 times (95% CI 1.2, 1.9) as likely to report a fall compared with those satisfied with their dwelling's light. After adjustment for major confounders, the likelihood of depression changed slightly, while the likelihood of a fall increased to 2.5 (95% CI 1.5, 4.2). Conclusion. Self-reported inadequate light in housing is independently associated with depression and falls. Increasing light in housing, a relatively inexpensive intervention, may improve two distinct health conditions. PMID:21563721
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vreeland, Robert R.
1989-10-01
In 1979 this study was initiated to determine the distribution, contribution, and value of artificially propagated fall chinook salmon from the Columbia River. Coded wire tagging (CWT) of hatchery fall chinook salmon began in 1979 with the 1978 brood and was completed in 1982 with the 1981 brood of fish at rearing facilities on the Columbia River system. From 18 to 20 rearing facilities were involved in the study each brood year. Nearly 14 million tagged fish, about 4% of the production, were released as part of this study over the four years, 1979 through 1982. Sampling for recoveries ofmore » these tagged fish occurred from 1980 through 1986 in the sport and commercial marine fisheries from Alaska through California, Columbia River fisheries, and returns to hatcheries and adjacent streams. The National Marine Fisheries Service coordinated this study among three fishery agencies: US Fish and Wildfire Service, Oregon Department of Fish and Wildlife, and Washington Department of Fisheries. The objectives of this study were to determine the distribution, fishery contribution, survival, and value of the production of fall chinook salmon from each rearing facility on the Columbia River system to Pacific coast salmon fisheries. To achieve these objectives fish from each hatchery were given a distinctive CWT. 81 refs., 20 figs., 68 tabs.« less
Freely Tunable Broadband Polarization Rotator for Terahertz Waves
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fan, Ren-Hao; Zhou, Yu; Ren, Xiao-Ping
2014-12-28
A freely tunable polarization rotator for broadband terahertz waves is demonstrated using a three-rotating-layer metallic grating structure, which can conveniently rotate the polarization of a linearly polarized terahertz wave to any desired direction with nearly perfect conversion efficiency. This low-cost, high-efficiency, and freely tunable device has potential applications as material analysis, wireless communication, and THz imaging.
Fall Take a Hike Features a New Poster Puzzler Challenge | Poster
The recent Take a Hike event, sponsored by Occupational Health Services, featured a new twist: A Poster Puzzler challenge courtesy of Scientific Publications, Graphics and Media. Participants were asked to identify words on six objects along the Hike path based on photographs that showed the objects with the words blurred out.
ERIC Educational Resources Information Center
McCloskey, Michael; And Others
Through everyday experience people acquire knowledge about how moving objects behave. For example, if a rock is thrown up into the air, it will fall back to earth. Research has shown that people's ideas about why moving objects behave as they do are often quite inconsistent with the principles of classical mechanics. In fact, many people hold a…
Takes Two to Tango: Essential Practices of Highly Effective Transfer Partnerships
ERIC Educational Resources Information Center
Fink, John; Jenkins, Davis
2017-01-01
Objective: The objective of this study was to describe practices of 2- and 4-year institutional partnerships effective in supporting transfer student success. Method: Using student records from the National Student Clearinghouse (NSC) for the entire 2007 fall cohort of first-time-in-college community college students nationwide, researchers…
Mazur, Katarzyna; Wilczyński, Krzysztof; Szewieczek, Jan
2016-01-01
Background Inpatient geriatric falls are a frequent complication of hospital care that results in significant morbidity and mortality. Objective Evaluate factors associated with falls in geriatric inpatients after implementation of the fall prevention program. Methods Prospective observational study comprised of 788 consecutive patients aged 79.5±7.6 years ( χ¯ ± standard deviation) (66% women and 34% men) admitted to the subacute geriatric ward. Comprehensive geriatric assessment (including Mini-Mental State Examination, Barthel Index of Activities of Daily Living, and modified Get-up and Go Test) was performed. Confusion Assessment Method was used for diagnosis of delirium. Patients were categorized into low, moderate, or high fall risk groups after clinical and functional assessment. Results About 15.9%, 21.1%, and 63.1% of participants were classified into low, moderate, and high fall risk groups, respectively. Twenty-seven falls were recorded in 26 patients. Increased fall probability was associated with age ≥76 years (P<0.001), body mass index (BMI) <23.5 (P=0.007), Mini-Mental State Examination <20 (P=0.004), Barthel Index <65 (P=0.002), hemoglobin <7.69 mmol/L (P=0.017), serum protein <70 g/L (P=0.008), albumin <32 g/L (P=0.001), and calcium level <2.27 mmol/L. Four independent factors associated with fall risk were included in the multivariate logistic regression model: delirium (odds ratio [OR] =7.33; 95% confidence interval [95% CI] =2.76–19.49; P<0.001), history of falls (OR =2.55; 95% CI =1.05–6.19; P=0.039), age (OR =1.14; 95% CI =1.05–1.23; P=0.001), and BMI (OR =0.91; 95% CI =0.83–0.99; P=0.034). Conclusion Delirium, history of falls, and advanced age seem to be the primary risk factors for geriatric falls in the context of a hospital fall prevention program. Higher BMI appears to be associated with protection against inpatient geriatric falls. PMID:27695303
Browne, Claire; Kingston, Claire; Keane, Claire
2014-10-01
Patients at risk of falling are regularly prescribed medicines which increase falls risk. Medication review is a widely advocated risk reduction strategy. The objectives of this descriptive study were to determine the number and types of falls risk medicines suitable for intervention, and to develop guidance to optimise the effectiveness of future medication related falls prevention initiatives. An Irish acute teaching hospital and tertiary referral centre. 50 hospital in-patients at risk of falls underwent medication review focused on falls prevention by a pharmacist. Falls risk medicines were identified, and reviewed. If scope to discontinue, dose reduce or switch to a safer alternative was identified by the pharmacist, the suggested medication changes were communicated to the patient's care team. Identification of the classes of falls risk medicines and types of prescriptions with greatest potential for intervention. Results The mean number of falls risk medicines prescribed to each patient was 4.8 (± 2.8) and the total number prescribed to the 50 patients was 238. Following medication review, the pharmacist identified 48 (20 %) as suitable for intervention. Consequently, 34 medication changes (70.8 %) were implemented. Four medication classes accounted for over 80 % of medication changes. These were anti-emetics, opioid analgesics, anti-cholinergic agents acting on the bladder and benzodiazepines/hypnotics. Intervention was statistically significantly more likely to be possible in the case of p.r.n. medicines compared to regular medicines (p < 0.001, Chi square test). Medication reviews focused on falls prevention took an average of 23.5 min per patient to complete. Medication reviews focused on falls prevention involve striking a balance between minimising medicines associated with falls and effectively treating medical conditions. We found only 20 % of falls risk medicines were suitable for change, and reviews were time consuming and resource intensive. However, targeting four medication classes, and being particularly alert to the potential to discontinue 'as required' medicines, has the potential to achieve most of the benefits of more comprehensive reviews. This information will guide the development of future falls risk medicine review initiatives in our hospital, increasing their feasibility in the acute hospital setting.
An intelligent robot for helping astronauts
NASA Technical Reports Server (NTRS)
Erickson, J. D.; Grimm, K. A.; Pendleton, T. W.
1994-01-01
This paper describes the development status of a prototype supervised intelligent robot for space application for purposes of (1) helping the crew of a spacecraft such as the Space Station with various tasks, such as holding objects and retrieving/replacing tools and other objects from/into storage, and (2) for purposes of retrieving detached objects, such as equipment or crew, that have become separated from their spacecraft. In addition to this set of tasks in this low-Earth-orbiting spacecraft environment, it is argued that certain aspects of the technology can be viewed as generic in approach, thereby offering insight into intelligent robots for other tasks and environments. Candidate software architectures and their key technical issues which enable real work in real environments to be accomplished safely and robustly are addressed. Results of computer simulations of grasping floating objects are presented. Also described are characterization results on the usable reduced gravity environment in an aircraft flying parabola (to simulate weightlessness) and results on hardware performance there. These results show it is feasible to use that environment for evaluative testing of dexterous grasping based on real-time vision of freely rotating and translating objects.
Independent motion detection with a rival penalized adaptive particle filter
NASA Astrophysics Data System (ADS)
Becker, Stefan; Hübner, Wolfgang; Arens, Michael
2014-10-01
Aggregation of pixel based motion detection into regions of interest, which include views of single moving objects in a scene is an essential pre-processing step in many vision systems. Motion events of this type provide significant information about the object type or build the basis for action recognition. Further, motion is an essential saliency measure, which is able to effectively support high level image analysis. When applied to static cameras, background subtraction methods achieve good results. On the other hand, motion aggregation on freely moving cameras is still a widely unsolved problem. The image flow, measured on a freely moving camera is the result from two major motion types. First the ego-motion of the camera and second object motion, that is independent from the camera motion. When capturing a scene with a camera these two motion types are adverse blended together. In this paper, we propose an approach to detect multiple moving objects from a mobile monocular camera system in an outdoor environment. The overall processing pipeline consists of a fast ego-motion compensation algorithm in the preprocessing stage. Real-time performance is achieved by using a sparse optical flow algorithm as an initial processing stage and a densely applied probabilistic filter in the post-processing stage. Thereby, we follow the idea proposed by Jung and Sukhatme. Normalized intensity differences originating from a sequence of ego-motion compensated difference images represent the probability of moving objects. Noise and registration artefacts are filtered out, using a Bayesian formulation. The resulting a posteriori distribution is located on image regions, showing strong amplitudes in the difference image which are in accordance with the motion prediction. In order to effectively estimate the a posteriori distribution, a particle filter is used. In addition to the fast ego-motion compensation, the main contribution of this paper is the design of the probabilistic filter for real-time detection and tracking of independently moving objects. The proposed approach introduces a competition scheme between particles in order to ensure an improved multi-modality. Further, the filter design helps to generate a particle distribution which is homogenous even in the presence of multiple targets showing non-rigid motion patterns. The effectiveness of the method is shown on exemplary outdoor sequences.
Exposure to fall hazards and safety climate in the aircraft maintenance industry.
Neitzel, Richard L; Seixas, Noah S; Harris, Michael J; Camp, Janice
2008-01-01
Falls represent a significant occupational hazard, particularly in industries with dynamic work environments. This paper describes rates of noncompliance with fall hazard prevention requirements, perceived safety climate and worker knowledge and beliefs, and the association between fall exposure and safety climate measures in commercial aircraft maintenance activities. Walkthrough observations were conducted on aircraft mechanics at two participating facilities (Sites A and B) to ascertain the degree of noncompliance. Mechanics at each site completed questionnaires concerning fall hazard knowledge, personal safety beliefs, and safety climate. Questionnaire results were summarized into safety climate and belief scores by workgroup and site. Noncompliance rates observed during walkthroughs were compared to the climate-belief scores, and were expected to be inversely associated. Important differences were seen in fall safety performance between the sites. The study provided a characterization of aircraft maintenance fall hazards, and also demonstrated the effectiveness of an objective hazard assessment methodology. Noncompliance varied by height, equipment used, location of work on the aircraft, shift, and by safety system. Although the expected relationship between safety climate and noncompliance was seen for site-average climate scores, workgroups with higher safety climate scores had greater observed noncompliance within Site A. Overall, use of engineered safety systems had a significant impact on working safely, while safety beliefs and climate also contributed, though inconsistently. The results of this study indicate that safety systems are very important in reducing noncompliance with fall protection requirements in aircraft maintenance facilities. Site-level fall safety compliance was found to be related to safety climate, although an unexpected relationship between compliance and safety climate was seen at the workgroup level within site. Finally, observed fall safety compliance was found to differ from self-reported compliance.
Central Nervous System Medication Burden and Serious Falls in Older Nursing Home Residents
Hanlon, Joseph T.; Zhao, Xinhua; Naples, Jennifer G.; Aspinall, Sherrie L.; Perera, Subashan; Nace, David A.; Castle, Nicholas G.; Greenspan, Susan L.; Thorpe, Carolyn T.
2016-01-01
Objectives To examine the association between CNS medication burden and serious falls in those with a recent fall history. Design Nested-case control study; cases matched to four controls by age, gender, and date. Setting US nursing homes Participants 5,556 residents age ≥ 65 with a recent fall history admitted to a nursing home between 1/1–9/30/2010 and followed until discharge, death, or 12/31/2010. Measurements Outcome was serious falls as per Medicare Part A and B ICD/CPT codes. CNS burden, from Medicare Part D data, was calculated by dividing the daily dose of each CNS agent (i.e., specific antidepressants, antiepileptic, antipsychotic, benzodiazepine and opioid receptor agonists) received during the six days prior to the index (outcome) date by the minimum effective geriatric daily dose and summing the results across medications. Results There were 367 cases and 1468 matched controls. Those taking 3+ CNS standardized daily doses were more likely to have a serious fall than those not taking any CNS medications (Adjusted Odds Ratio 1.83; 95% confidence interval 1.35–2.48). There was no significant difference in fall risk for residents taking >0 to <3 CNS standardized daily doses compared to residents taking no CNS medications (Adjusted Odds Ratio 0.85; 95% CI 0.63–1.15). Conclusion CNS medication burden, approximately 3+ standardized daily doses, was associated with an increased risk of serious falls in nursing home residents with recent fall. Clinicians should be vigilant for opportunities to discontinue or decrease the doses of individual CNS medications and/or consider non-pharmacological alternatives. Such interventions that reduce use of CNS medications in nursing homes could reduce fall rates but further research is needed to confirm this. PMID:28152179
Rosa, Nayza M. B.; Queiroz, Bárbara Z.; Lopes, Renata A.; Sampaio, Natalia R.; Pereira, Daniele S.; Pereira, Leani S. M.
2016-01-01
ABSTRACT Background Low back pain (LBP) is a common musculoskeletal condition among elders and is associated with falls. However, the underlying biological risk factors for falling among elders with LBP has been poorly investigated. The Physiological Profile Assessment (PPA) is a validated fall-risk assessment tool that involves the direct assessment of sensorimotor abilities and may contribute to the understanding of risk factors for falls among elders with LBP. Objective To assess fall risk using the PPA in elders with and without LBP. Method This is an observational, comparative, cross-sectional study with elders aged ≥65 years. The present study was conducted with a subsample of participants from the Back Complaints in the Elders (BACE) - Brazil study. Fall risk was assessed using the PPA, which contains five tests: visual contrast sensitivity, hand reaction time, quadriceps strength, lower limb proprioception, and postural sway. Results Study participants included 104 individuals with average age of 72.3 (SD=4.0) years, divided into two groups: GI) 52 participants with LBP; GII) 52 participants without LBP. The participants with LBP had a significantly higher fall risk (1.10 95% CI 0.72 to 1.48), greater postural sway (49.78 95% CI 13.54 to 86.01), longer reaction time (58.95 95% CI 33.24 to 84.65), and lower quadriceps strength (–4.42 95% CI –8.24 to –0.59) compared to asymptomatic participants. There was no significant difference for vision and proprioception tests between LBP and non-LBP participants. Conclusion Elders with LBP have greater risk for falls than those without LBP. Our results suggest fall-risk screening may be sensible in elders with LBP. PMID:27683833
Race and fall risk: data from the National Health and Aging Trends Study (NHATS).
Sun, Daniel Q; Huang, Jin; Varadhan, Ravi; Agrawal, Yuri
2016-01-01
the objective of this study was to explore whether race-based difference in fall risk may be mediated by environmental and physical performance risk factors. using data from a nationally representative longitudinal survey of 7,609 community-dwelling participants in the National Health and Aging Trends Study (NHATS), we evaluated whether racial differences in fall risk may be explained by physical performance level (measured by the Short Physical Performance Battery), mobility disability, physical activity level and likelihood of living alone. Multivariate Poisson regression and mediation models were used in analyses. in whites and blacks, the annual incidence of 'any fall' was 33.8 and 27.1%, respectively, and the annual incidence of 'recurrent falls' was 15.5 and 12.3%, respectively. Compared with whites, blacks had relative risks of 0.7 (95% confidence interval 0.6-0.8) and 0.6 (0.5-0.8) for sustaining any fall and recurrent falls, respectively, in adjusted analyses. Blacks had poorer performance on the SPPB (P < 0.001), higher levels of mobility disability (P < 0.001), similar levels of physical activity (P = 0.19) and were equally likely to live alone relative to whites (P = 0.77). Mediation analysis revealed that these risk factors collectively acted as suppressors and none of these factors accounted for the racial differences in fall risk observed. relative to whites, blacks were at 30 and 40% decreased risk of sustaining any fall and recurrent falls, respectively. This difference in risk remains unexplained. © The Author 2016. Published by Oxford University Press on behalf of the British Geriatrics Society. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Factors associated with falls among older adults living in institutions
2013-01-01
Background Falls have enormous impact in older adults. Yet, there is insufficient evidence regarding the effectiveness of preventive interventions in this setting. The objectives were to measure the frequency of falls and associated factors among older people living institutions. Methods Data were obtained from a survey on a probabilistic sample of residents aged ≥65 years, drawn in 1998-99 from institutions of Madrid (Spain). Residents, their caregivers, and facility physicians were interviewed. Fall rates were computed based on the number of physician-reported falls in the preceding 30 days. Adjusted rate ratios were computed using negative binomial regression models, including age, sex, cognitive status, functional dependence, number of diseases, and polypharmacy. Results The final sample comprised 733 residents. The fall rate was 2.4 falls per person-year (95% confidence interval [CI], 2.04-2.82). The strongest risk factor was number of diseases, with an adjusted rate ratio (RR) of 1.32 (95% CI, 1.17-1.50) for each additional diagnosis. Other variables associated with falls were: urinary incontinence (RR = 2.56 [95% CI, 1.32-4.94]); antidepressant use (RR = 2.32 [95% CI, 1.22-4.40]); arrhythmias (RR = 2.00 [95% CI, 1.05-3.81]); and polypharmacy (RR = 1.07 [95% CI, 0.95-1.21], for each additional medication). The attributable fraction for number of diseases (with reference to those with ≤ 1 condition) was 84% (95% CI, 45-95%). Conclusions Number of diseases was the main risk factor for falls in this population of institutionalized older adults. Other variables associated with falls, probably more amenable to preventive action, were urinary incontinence, antidepressants, arrhythmias, and polypharmacy. Virtual slides The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/3916151157277337 PMID:23320746
Modified 30-second Sit to Stand test predicts falls in a cohort of institutionalized older veterans
Chassé, Kathleen
2017-01-01
Physical function performance tests, including sit to stand tests and Timed Up and Go, assess the functional capacity of older adults. Their ability to predict falls warrants further investigation. The objective was to determine if a modified 30-second Sit to Stand test that allowed upper extremity use and Timed Up and Go test predicted falls in institutionalized Veterans. Fifty-three older adult Veterans (mean age = 91 years, 49 men) residing in a long-term care hospital completed modified 30-second Sit to Stand and Timed Up and Go tests. The number of falls over one year was collected. The ability of modified 30-second Sit to Stand or Timed Up and Go to predict if participants had fallen was examined using logistic regression. The ability of these tests to predict the number of falls was examined using negative binomial regression. Both analyses controlled for age, history of falls, cognition, and comorbidities. The modified 30-second Sit to Stand was significantly (p < 0.05) related to if participants fell (odds ratio = 0.75, 95% confidence interval = 0.58, 0.97) and the number of falls (incidence rate ratio = 0.82, 95% confidence interval = 0.68, 0.98); decreased repetitions were associated with increased number of falls. Timed Up and Go was not significantly (p > 0.05) related to if participants fell (odds ratio = 1.03, 95% confidence interval = 0.96, 1.10) or the number of falls (incidence rate ratio = 1.01, 95% confidence interval = 0.98, 1.05). The modified 30-second Sit to Stand that allowed upper extremity use offers an alternative method to screen for fall risk in older adults in long-term care. PMID:28464024
Hauer, Klaus A; Kempen, Gertrudis I J M; Schwenk, Michael; Yardley, Lucy; Beyer, Nina; Todd, Chris; Oster, Peter; Zijlstra, G A Rixt
2011-01-01
Measures of fear of falling have not yet been validated in patients with dementia, leaving a methodological gap that limits research in a population at high risk of falling and fall-related consequences. The objectives of this study are to determine: (1) the validity of the 7-item Short Falls Efficacy Scale International (Short FES-I) in geriatric patients with and without cognitive impairment, and (2) the sensitivity to change of the 10-item Falls Efficacy Scale (FES), the 16-item FES-I and the 7-item Short FES-I in geriatric patients with dementia. Cross-sectional data of community-dwelling older adults and geriatric rehabilitation patients (n = 284) collected during face-to-face interviews were used to determine construct and discriminant validity by testing for differences within variables related to fear of falling. Sensitivity to change was studied in an intervention study including patients with mild to moderate dementia (n = 130) as determined by standard response means (SRMs). The Short FES-I showed excellent construct and discriminant validity in the total group and subsamples according to cognitive status. Sensitivity to change was adequate to good in the FES (range SRM: 0.18-0.77) and FES-I (range SRM: 0.21-0.74), with the Short FES-I showing the highest peak sensitivity to change (range SRM: 0.18-0.91). The Short FES-I is a valid measure to assess fear of falling in frail older adults with and without cognitive impairment, yet it may show floor effects in higher functioning older people. All scales, including the Short FES-I, were sensitive to detecting intervention-induced changes in concerns about falling in geriatric patients with dementia. Copyright © 2010 S. Karger AG, Basel.
Modified 30-second Sit to Stand test predicts falls in a cohort of institutionalized older veterans.
Applebaum, Eva V; Breton, Dominic; Feng, Zhuo Wei; Ta, An-Tchi; Walsh, Kayley; Chassé, Kathleen; Robbins, Shawn M
2017-01-01
Physical function performance tests, including sit to stand tests and Timed Up and Go, assess the functional capacity of older adults. Their ability to predict falls warrants further investigation. The objective was to determine if a modified 30-second Sit to Stand test that allowed upper extremity use and Timed Up and Go test predicted falls in institutionalized Veterans. Fifty-three older adult Veterans (mean age = 91 years, 49 men) residing in a long-term care hospital completed modified 30-second Sit to Stand and Timed Up and Go tests. The number of falls over one year was collected. The ability of modified 30-second Sit to Stand or Timed Up and Go to predict if participants had fallen was examined using logistic regression. The ability of these tests to predict the number of falls was examined using negative binomial regression. Both analyses controlled for age, history of falls, cognition, and comorbidities. The modified 30-second Sit to Stand was significantly (p < 0.05) related to if participants fell (odds ratio = 0.75, 95% confidence interval = 0.58, 0.97) and the number of falls (incidence rate ratio = 0.82, 95% confidence interval = 0.68, 0.98); decreased repetitions were associated with increased number of falls. Timed Up and Go was not significantly (p > 0.05) related to if participants fell (odds ratio = 1.03, 95% confidence interval = 0.96, 1.10) or the number of falls (incidence rate ratio = 1.01, 95% confidence interval = 0.98, 1.05). The modified 30-second Sit to Stand that allowed upper extremity use offers an alternative method to screen for fall risk in older adults in long-term care.
Fall Detection System for the Elderly Based on the Classification of Shimmer Sensor Prototype Data
Ahmed, Moiz; Mehmood, Nadeem; Mehmood, Amir; Rizwan, Kashif
2017-01-01
Objectives Falling in the elderly is considered a major cause of death. In recent years, ambient and wireless sensor platforms have been extensively used in developed countries for the detection of falls in the elderly. However, we believe extra efforts are required to address this issue in developing countries, such as Pakistan, where most deaths due to falls are not even reported. Considering this, in this paper, we propose a fall detection system prototype that s based on the classification on real time shimmer sensor data. Methods We first developed a data set, ‘SMotion’ of certain postures that could lead to falls in the elderly by using a body area network of Shimmer sensors and categorized the items in this data set into age and weight groups. We developed a feature selection and classification system using three classifiers, namely, support vector machine (SVM), K-nearest neighbor (KNN), and neural network (NN). Finally, a prototype was fabricated to generate alerts to caregivers, health experts, or emergency services in case of fall. Results To evaluate the proposed system, SVM, KNN, and NN were used. The results of this study identified KNN as the most accurate classifier with maximum accuracy of 96% for age groups and 93% for weight groups. Conclusions In this paper, a classification-based fall detection system is proposed. For this purpose, the SMotion data set was developed and categorized into two groups (age and weight groups). The proposed fall detection system for the elderly is implemented through a body area sensor network using third-generation sensors. The evaluation results demonstrate the reasonable performance of the proposed fall detection prototype system in the tested scenarios. PMID:28875049
Pediatric falls from buildings: defining the burden of injury in Hawai'i.
Sarkar, Joy; Wolfe, Stacey Q; Speck, Cora; Woods, Elizabeth; Lustik, Michael B; Edwards, Kurt D; Edwards, Mary J
2014-05-01
Falls from buildings, including houses, are an important cause of childhood injury in the United States; however, no study has previously examined the impact of this problem in Hawai'i. The objective of this study is to categorize the demographics and injury circumstances of pediatric falls from buildings in Hawai'i and compare to other US cities. Patients age 10 and under who were injured in nonfatal accidental falls from buildings in Hawai'i between 2005 and 2011 were identified retrospectively from a statewide repository of hospital billing data. The Hawai'i death certificate database was searched separately for deaths in children age 10 and under due to falls from buildings, with data available from 1991 through 2011. Data was reviewed for demographics, circumstances surrounding the injury, and level of hospital treatment. During the 7-year period for nonfatal injuries, 416 fall-related injuries were identified in children age 10 and younger. Of these, 86 required hospitalization. The rate of nonfatal injury in Hawai'i County was twice that of Honolulu and Maui Counties, and three times that of Kaua'i County. There were 9 fatal falls over a 21-year period. The population based incidence for nonfatal injuries was three-fold higher than that reported in the city of Dallas. The rate of hospitalizations following building falls was more than twice as high as the national average, and that of New York City, but similar to that of California. Strategies for education and environmental modification are reviewed, which may be helpful in reducing the incidence of pediatric falls from buildings in Hawai'i.
Automated In-Home Fall Risk Assessment and Detection Sensor System for Elders.
Rantz, Marilyn; Skubic, Marjorie; Abbott, Carmen; Galambos, Colleen; Popescu, Mihail; Keller, James; Stone, Erik; Back, Jessie; Miller, Steven J; Petroski, Gregory F
2015-06-01
Falls are a major problem for the elderly people leading to injury, disability, and even death. An unobtrusive, in-home sensor system that continuously monitors older adults for fall risk and detects falls could revolutionize fall prevention and care. A fall risk and detection system was developed and installed in the apartments of 19 older adults at a senior living facility. The system includes pulse-Doppler radar, a Microsoft Kinect, and 2 web cameras. To collect data for comparison with sensor data and for algorithm development, stunt actors performed falls in participants' apartments each month for 2 years and participants completed fall risk assessments (FRAs) using clinically valid, standardized instruments. The FRAs were scored by clinicians and recorded by the sensing modalities. Participants' gait parameters were measured as they walked on a GAITRite mat. These data were used as ground truth, objective data to use in algorithm development and to compare with radar and Kinect generated variables. All FRAs are highly correlated (p < .01) with the Kinect gait velocity and Kinect stride length. Radar velocity is correlated (p < .05) to all the FRAs and highly correlated (p < .01) to most. Real-time alerts of actual falls are being sent to clinicians providing faster responses to urgent situations. The in-home FRA and detection system has the potential to help older adults remain independent, maintain functional ability, and live at home longer. © The Author 2015. 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.
Marschollek, Michael; Rehwald, Anja; Wolf, Klaus-Hendrik; Gietzelt, Matthias; Nemitz, Gerhard; zu Schwabedissen, Hubertus Meyer; Schulze, Mareike
2011-06-28
Fall events contribute significantly to mortality, morbidity and costs in our ageing population. In order to identify persons at risk and to target preventive measures, many scores and assessment tools have been developed. These often require expertise and are costly to implement. Recent research investigates the use of wearable inertial sensors to provide objective data on motion features which can be used to assess individual fall risk automatically. So far it is unknown how well this new method performs in comparison with conventional fall risk assessment tools. The aim of our research is to compare the predictive performance of our new sensor-based method with conventional and established methods, based on prospective data. In a first study phase, 119 inpatients of a geriatric clinic took part in motion measurements using a wireless triaxial accelerometer during a Timed Up&Go (TUG) test and a 20 m walk. Furthermore, the St. Thomas Risk Assessment Tool in Falling Elderly Inpatients (STRATIFY) was performed, and the multidisciplinary geriatric care team estimated the patients' fall risk. In a second follow-up phase of the study, 46 of the participants were interviewed after one year, including a fall and activity assessment. The predictive performances of the TUG, the STRATIFY and team scores are compared. Furthermore, two automatically induced logistic regression models based on conventional clinical and assessment data (CONV) as well as sensor data (SENSOR) are matched. Among the risk assessment scores, the geriatric team score (sensitivity 56%, specificity 80%) outperforms STRATIFY and TUG. The induced logistic regression models CONV and SENSOR achieve similar performance values (sensitivity 68%/58%, specificity 74%/78%, AUC 0.74/0.72, +LR 2.64/2.61). Both models are able to identify more persons at risk than the simple scores. Sensor-based objective measurements of motion parameters in geriatric patients can be used to assess individual fall risk, and our prediction model's performance matches that of a model based on conventional clinical and assessment data. Sensor-based measurements using a small wearable device may contribute significant information to conventional methods and are feasible in an unsupervised setting. More prospective research is needed to assess the cost-benefit relation of our approach.
2011-01-01
Background Fall events contribute significantly to mortality, morbidity and costs in our ageing population. In order to identify persons at risk and to target preventive measures, many scores and assessment tools have been developed. These often require expertise and are costly to implement. Recent research investigates the use of wearable inertial sensors to provide objective data on motion features which can be used to assess individual fall risk automatically. So far it is unknown how well this new method performs in comparison with conventional fall risk assessment tools. The aim of our research is to compare the predictive performance of our new sensor-based method with conventional and established methods, based on prospective data. Methods In a first study phase, 119 inpatients of a geriatric clinic took part in motion measurements using a wireless triaxial accelerometer during a Timed Up&Go (TUG) test and a 20 m walk. Furthermore, the St. Thomas Risk Assessment Tool in Falling Elderly Inpatients (STRATIFY) was performed, and the multidisciplinary geriatric care team estimated the patients' fall risk. In a second follow-up phase of the study, 46 of the participants were interviewed after one year, including a fall and activity assessment. The predictive performances of the TUG, the STRATIFY and team scores are compared. Furthermore, two automatically induced logistic regression models based on conventional clinical and assessment data (CONV) as well as sensor data (SENSOR) are matched. Results Among the risk assessment scores, the geriatric team score (sensitivity 56%, specificity 80%) outperforms STRATIFY and TUG. The induced logistic regression models CONV and SENSOR achieve similar performance values (sensitivity 68%/58%, specificity 74%/78%, AUC 0.74/0.72, +LR 2.64/2.61). Both models are able to identify more persons at risk than the simple scores. Conclusions Sensor-based objective measurements of motion parameters in geriatric patients can be used to assess individual fall risk, and our prediction model's performance matches that of a model based on conventional clinical and assessment data. Sensor-based measurements using a small wearable device may contribute significant information to conventional methods and are feasible in an unsupervised setting. More prospective research is needed to assess the cost-benefit relation of our approach. PMID:21711504
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mueller, Robert
2004-10-01
Pacific Northwest National Laboratory conducted video-based boat surveys in fall 2003 to identify spawning areas for fall Chinook salmon (Oncorhynchus tshawytscha) in deep water (>1 m) downstream of Bonneville Dam. This report documents the number and extent of Chinook salmon spawning near Ives and Pierce islands of the Columbia River, and is the fifth in a series of reports prepared since 1999. The primary objective of this study was to find deepwater spawning locations of fall Chinook salmon in the main Columbia River channel, collect additional data on physical habitat parameters at spawning sites, and provide estimates of adult spawnersmore » in the surveyed area. The secondary objective was to document the occurrence of any chum salmon (O. keta) redds in the deeper sections near below Hamilton Creek. Results from the 2003 study show a continuing trend upward in the number of fall Chinook salmon redds found within the survey zones. The number of fall Chinook redds found in the Ives Pierce Island complex (river km 228.5) has increased by a factor of five since the surveys began in 1999. The total number of redds found during 2003 was 336, which compares to 192 in 2002, 43 in 2001, 76 in 2000, and 64 in 1999. The redds encompassed an area of 13.7 ha occurring adjacent to the lower part of Ives Island and Pierce Island. Peak spawning activity, based on redd counts and live fish seen near redds, was on or near November 24, 2003. An expanded redd count based on percentage of video coverage in the primary and secondary search zones was 3,218 fall Chinook salmon redds in water exceeding 1 m deep and flowing at about 125 kcfs. Fall Chinook salmon redds were found at water depths from 1.07 to 7.6 m and were constructed predominantly of medium cobbles ranging from 7.6 to 15.2 cm in diameter. Two chum salmon redds were found in a small location downstream from Hamilton Creek in water depths of approximately 1 m. No salmon redds were found in other areas searched, including near Woodward, Tanner, and McCord creeks.« less
Mansfield, Avril; Aqui, Anthony; Centen, Andrew; Danells, Cynthia J; DePaul, Vincent G; Knorr, Svetlana; Schinkel-Ivy, Alison; Brooks, Dina; Inness, Elizabeth L; McIlroy, William E; Mochizuki, George
2015-06-06
Falls are one of the most common medical complications post-stroke. Physical exercise, particularly exercise that challenges balance, reduces the risk of falls among healthy and frail older adults. However, exercise has not proven effective for preventing falls post-stroke. Falls ultimately occur when an individual fails to recover from a loss of balance. Thus, training to specifically improve reactive balance control could prevent falls. Perturbation training aims to improve reactive balance control by repeatedly exposing participants to postural perturbations. There is emerging evidence that perturbation training reduces fall rates among individuals with neurological conditions, such as Parkinson disease. The primary aim of this work is to determine if perturbation-based balance training can reduce occurrence of falls in daily life among individuals with chronic stroke. Secondary objectives are to determine the effect of perturbation training on balance confidence and activity restriction, and functional balance and mobility. Individuals with chronic stroke will be recruited. Participants will be randomly assigned to one of two groups: 1) perturbation training, or 2) 'traditional' balance training. Perturbation training will involve both manual perturbations (e.g., a push or pull from a physiotherapist), and rapid voluntary movements to cause a loss of balance. Training will occur twice per week for 6 weeks. Participants will record falls and activity for 12 months following completion of the training program. Standardized clinical tools will be used to assess functional balance and mobility, and balance confidence before and after training. Falls are a significant problem for those with stroke. Despite the large body of work demonstrating effective interventions, such as exercise, for preventing falls in other populations, there is little evidence for interventions that prevent falls post-stroke. The proposed study will investigate a novel and promising intervention: perturbation training. If effective, this training has the potential to not only prevent falls, but to also improve safe independent mobility and engagement in daily activities for those with stroke. Current Controlled Trials: ISRCTN05434601 .
Ang, Hui Ting; Lim, Ka Keat; Kwan, Yu Heng; Tan, Pui San; Yap, Kai Zhen; Banu, Zafirah; Tan, Chuen Seng; Fong, Warren; Thumboo, Julian; Ostbye, Truls; Low, Lian Leng
2018-06-23
Falls in individuals aged ≥ 60 years may result in injury, hospitalisation or death. The role of anti-hypertensive medications in falls among older adults is unclear. The objective of this study was to assess the association of six anti-hypertensive medication classes, namely α-blockers (AB), angiotensin converting enzyme inhibitors (ACEi), angiotensin receptor blockers (ARB), β-blockers (BB), calcium channel blockers (CCB) and diuretics, with the risk of falls, injurious falls or recurrent falls in individuals aged ≥ 60 years compared with non-users. We performed systematic searches in PubMed, EMBASE and CINAHL and included cohort, case-control and cross-sectional studies that investigated the associations between the use of anti-hypertensive medication classes and the risk of falls, injurious falls or recurrent falls in older adults (≥ 60 years) reported in English. We assessed study quality using the Newcastle-Ottawa Scale (NOS). Unadjusted and adjusted odds ratios (ORs) were pooled using random effects model. We performed meta-analyses for each anti-hypertensive medication class and each fall outcome. We also performed sensitivity analyses by pooling studies of high quality and subgroup analyses among studies with an average age of ≥ 80 years. Seventy-eight articles (where 74, 34, 27, 18, 13 and 11 of them examined diuretics, BB, CCB, ACEi, AB and ARB, respectively) met our inclusion and exclusion criteria; we pooled estimates from 60 articles. ACEi [OR 0.85, 95% confidence interval (CI) 0.81-0.89], BB (OR 0.84, 95% CI 0.76-0.93) and CCB (OR 0.81, 95% CI 0.74-0.90) use were associated with a lower risk of injurious falls than in non-users. Results in sensitivity and subgroup analyses were largely consistent. The use of ACEi, BB or CCB among older adults may be associated with a lower risk of injurious falls than non-use.
Coutinho, Evandro S F; Fletcher, Astrid; Bloch, Katia V; Rodrigues, Laura C
2008-08-26
Fracture after falling has been identified as an important problem in public health. Most studies of risk factors for fractures due to falls have been carried out in developed countries, although the size of the elderly population is increasing fast in middle income countries. The objective of this paper is to identify risk factors for fall related to severe fractures in those aged 60 or more in a middle-income country. A case-control study was carried out in Rio de Janeiro-Brazil based general hospitals between 2002-2003. Two hundred-fifty hospitalised cases of fracture were matched with 250 community controls by sex, age group and living area. Data were collected for socio-demographic variables, health status and drugs used before the fall. A conditional logistic regression model was fitted to identify variables associated with the risk of fall related severe fracture. Low body mass index, cognitive impairment, stroke and lack of urine control were associated with increased risk of severe fall related fractures. Benzodiazepines and muscle relaxants were also related to an increased risk of severe fractures while moderate use of alcohol was associated with reduced risk. Although the association between benzodiazepines and fractures due to fall has been consistently demonstrated for old people, this has not been the case for muscle relaxant drugs. The decision to prescribe muscle relaxants for elderly people should take into account the risk of severe fracture associated with these drugs.
[EXTRINSIC AND INTRINSIC FACTORS FOR FALLS THAT CAUSED HIP FRACTURE].
Tsur, Atzmon; Shakeer, Nael; Segal, Zvi; Itah, Dorit; Eluz, Dana
2017-05-01
Among the reasons described as possibly causing falls in older and elderly people are extrinsic factors such as bumping into objects, slipping on a wet floor, etc., and intrinsic factors - those that occur suddenly without warning. To investigate the connection between the reasons for falls, extrinsic or intrinsic and different medical and nonmedical factors. The survey included 82 people, 53 women and 29 men, who fell and broke their hip, underwent surgery, and were treated at the Rehabilitation Department. Data showed that 39 people fell due to extrinsic factors and 43 due to intrinsic reasons. We examined the correlation with several factors, both medical and non-medical, that may have influenced the scenario of each group. Falls due to extrinsic reasons took place at all hours of the day and night, mainly in people who were alone and who wore shoes or sandals at the time of the fall and who either suffered from slight or no disturbances in attention and concentration. Falls due to intrinsic reasons occurred mainly during rest or sleep hours, in people who walked barefoot or with socks or slippers and who suffered moderate or severe disturbances in attention and concentration. Although the differences in the extrinsic vs. intrinsic reasons for falls that led to broken hips were fairly clear, it would be difficult to recommend new tools for prevention of this phenomenon. Trying to predict an infrequent future event such as a traumatic fall is inherently difficult.
Narayanan, V.; Dickinson, A.; Victor, C.; Griffiths, C.; Humphrey, D.
2016-01-01
Objectives There is an urgent need to improve the care of older people at risk of falls or who experience falls in mental health settings. The aims of this study were to evaluate the individual falls risk assessment tools adopted by National Health Service (NHS) mental health trusts in England and healthcare boards in Wales, to evaluate the comprehensiveness of these tools and to review their predictive validity. Methods All NHS mental health trusts in England (n = 56) and healthcare boards in Wales (n = 6) were invited to supply their falls policies and other relevant documentation (e.g. local falls audits). In order to check the comprehensiveness of tools listed in policy documents, the risk variables of the tools adopted by the mental health trusts’ policies were compared with the 2004 National Institute for Health and Care Excellence (NICE) falls prevention guidelines. A comprehensive analytical literature review was undertaken to evaluate the predictive validity of the tools used in these settings. Results Falls policies were obtained from 46 mental health trusts. Thirty-five policies met the study inclusion criteria and were included in the analysis. The main falls assessment tools used were the St. Thomas’ Risk Assessment Tool in Falling Elderly Inpatients (STRATIFY), Falls Risk Assessment Scale for the Elderly, Morse Falls Scale (MFS) and Falls Risk Assessment Tool (FRAT). On detailed examination, a number of different versions of the FRAT were evident; validated tools had inconsistent predictive validity and none of them had been validated in mental health settings. Conclusions Falls risk assessment is the most commonly used component of risk prevention strategies, but most policies included unvalidated tools and even well validated tool such as the STRATIFY and the MFS that are reported to have inconsistent predictive accuracy. This raises questions about operational usefulness, as none of these tools have been tested in acute mental health settings. The falls risk assessment tools from only four mental health trusts met all the recommendations of the NICE falls guidelines on multifactorial assessment for prevention of falls. The recent NICE (2013) guidance states that tools predicting risk using numeric scales should no longer be used; however, multifactorial risk assessment and interventions tailored to patient needs is recommended. Trusts will need to update their policies in response to this guidance. PMID:26395210
Negative Gauge Pressure Moisture Management and Secure Adherence Device for Prosthetic Limbs
2013-03-01
prosthesis feels like it is sliding up and down or falling off when I am active. D. I have been more active than normal as a result of this prosthesis ...temperature. 3. My prosthesis feels like it is sliding up and down or falling off when I am active. 4. I have been more active than normal as a result of...objective of this research was to develop and test a novel prosthesis incorporating a negative gauge pressure moisture management and secure
2013-01-01
Background Falls are a leading cause of morbidity and mortality in older adults. Although numerous trials of falls prevention interventions have been completed, there is extensive variation in their intervention components and clinical context, such that the key elements of an effective falls prevention program remain unclear to patients, clinicians, and policy-makers. Our objective is to identify the most effective interventions and combinations of interventions that prevent falls though a systematic review and meta-analysis, including a network meta-analysis. Methods/Design We will search for published (e.g., MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, Ageline) and unpublished (e.g., trial registries, dissertations) randomised clinical trials (RCTs) in all languages examining interventions to prevent falls compared to usual care or other falls prevention interventions among adults aged ≥65 years from all settings (e.g., community, acute care, long-term care, and rehabilitation). The primary outcomes are number of injurious falls and number of hospitalizations due to falls. Secondary outcomes include falls rate, number of fallers, number of emergency room visits due to falls, number of physician visits due to falls, number of fractures, costs, and number of intervention-related harms (e.g., muscle soreness related to exercise). We will calibrate our eligibility criteria amongst the team and two independent team members will screen the literature search results in duplicate. Conflicts will be resolved through team discussion. A similar process will be used for data abstraction and quality appraisal with the Cochrane risk of bias tool. Our results will be synthesized descriptively and a random effects meta-analysis will be conducted if the studies are deemed methodologically, clinically, and statistically (e.g., I2<60%) similar. If appropriate, a network meta-analysis will be conducted, which will allow the comparison of interventions that have not been compared in head-to-head RCTs, as well as the effectiveness of interventions. Discussion We will identify the most effective interventions and combinations of interventions that prevent falls in older people. Our results will be used to optimize falls prevention strategies, and our goal is to ultimately improve the health of seniors internationally. Trial registration PROSPERO registry number: CRD42013004151 PMID:23738619
Preventing falls among older people with mental health problems: a systematic review
2014-01-01
Background Falls are a leading cause of mortality and morbidity in older people and the risk of falling is exacerbated by mental health conditions. Existing reviews have focused on people with dementia and cognitive impairment, but not those with other mental health conditions or in mental health settings. The objective of this review is to evaluate the effectiveness of fall prevention interventions for older people with mental health problems being cared for across all settings. Methods A systematic review of fall prevention interventions for older people with mental health conditions. We undertook electronic database and lateral searches to identify studies reporting data on falls or fall related injuries. Searches were initially conducted in February 2011 and updated in November 2012 and October 2013; no date restrictions were applied. Studies were assessed for risk of bias. Due to heterogeneity results were not pooled but are reported narratively. Results Seventeen RCTs and four uncontrolled studies met the inclusion criteria; 11 involved single interventions and ten multifactorial. Evidence relating to fall reduction was inconsistent. Eight of 14 studies found a reduction in fallers (statistically significant in five), and nine of 14 reported a significant reduction in rate or number of falls. Four studies found a non-significant increase in falls. Multifactorial, multi-disciplinary interventions and those involving exercise, medication review and increasing staff awareness appear to reduce the risk of falls but evidence is mixed and study quality varied. Changes to the environment such as increased supervision or sensory stimulation to reduce agitation may be promising for people with dementia but further evaluation is needed. Most of the studies were undertaken in nursing and residential homes, and none in mental health hospital settings. Conclusions There is a dearth of falls research in mental health settings or which focus on patients with mental health problems despite the high number of falls experienced by this population group. This review highlights the lack of robust evidence to support practitioners to implement practices that prevent people with mental health problems from falling. PMID:24552165
Singh, Devinder K A; Pillai, Sharmila G K; Tan, Sin Thien; Tai, Chu Chiau; Shahar, Suzana
2015-01-01
Physical performance and balance declines with aging and may lead to increased risk of falls. Physical performance tests may be useful for initial fall-risk screening test among community-dwelling older adults. Physiological profile assessment (PPA), a composite falls risk assessment tool is reported to have 75% accuracy to screen for physiological falls risk. PPA correlates with Timed Up and Go (TUG) test. However, the association between many other commonly used physical performance tests and PPA is not known. The aim of the present study was to examine the association between physiological falls risk measured using PPA and a battery of physical performance tests. One hundred and forty older adults from a senior citizens club in Kuala Lumpur, Malaysia (94 females, 46 males), aged 60 years and above (65.77±4.61), participated in this cross-sectional study. Participants were screened for falls risk using PPA. A battery of physical performance tests that include ten-step test (TST), short physical performance battery (SPPB), functional reach test (FRT), static balance test (SBT), TUG, dominant hand-grip strength (DHGS), and gait speed test (GST) were also performed. Spearman's rank correlation and binomial logistic regression were performed to examine the significantly associated independent variables (physical performance tests) with falls risk (dependent variable). Approximately 13% older adults were at high risk of falls categorized using PPA. Significant differences (P<0.05) were demonstrated for age, TST, SPPB, FRT, SBT, TUG between high and low falls risk group. A significant (P<0.01) weak correlation was found between PPA and TST (r=0.25), TUG (r=0.27), SBT (r=0.23), SPPB (r=-0.33), and FRT (r=-0.23). Binary logistic regression results demonstrated that SBT measuring postural sways objectively using a balance board was the only significant predictor of physiological falls risk (P<0.05, odds ratio of 2.12). The reference values of physical performance tests in our study may be used as a guide for initial falls screening to categorize high and low physiological falls risk among community-dwelling older adults. A more comprehensive assessment of falls risk can be performed thereafter for more specific intervention of underlying impairments.
Multi-documents summarization based on clustering of learning object using hierarchical clustering
NASA Astrophysics Data System (ADS)
Mustamiin, M.; Budi, I.; Santoso, H. B.
2018-03-01
The Open Educational Resources (OER) is a portal of teaching, learning and research resources that is available in public domain and freely accessible. Learning contents or Learning Objects (LO) are granular and can be reused for constructing new learning materials. LO ontology-based searching techniques can be used to search for LO in the Indonesia OER. In this research, LO from search results are used as an ingredient to create new learning materials according to the topic searched by users. Summarizing-based grouping of LO use Hierarchical Agglomerative Clustering (HAC) with the dependency context to the user’s query which has an average value F-Measure of 0.487, while summarizing by K-Means F-Measure only has an average value of 0.336.
BIAS: Bioinformatics Integrated Application Software.
Finak, G; Godin, N; Hallett, M; Pepin, F; Rajabi, Z; Srivastava, V; Tang, Z
2005-04-15
We introduce a development platform especially tailored to Bioinformatics research and software development. BIAS (Bioinformatics Integrated Application Software) provides the tools necessary for carrying out integrative Bioinformatics research requiring multiple datasets and analysis tools. It follows an object-relational strategy for providing persistent objects, allows third-party tools to be easily incorporated within the system and supports standards and data-exchange protocols common to Bioinformatics. BIAS is an OpenSource project and is freely available to all interested users at http://www.mcb.mcgill.ca/~bias/. This website also contains a paper containing a more detailed description of BIAS and a sample implementation of a Bayesian network approach for the simultaneous prediction of gene regulation events and of mRNA expression from combinations of gene regulation events. hallett@mcb.mcgill.ca.
The reliability of the Hendrich Fall Risk Model in a geriatric hospital.
Heinze, Cornelia; Halfens, Ruud; Dassen, Theo
2008-12-01
Aims and objectives. The purpose of this study was to test the interrater reliability of the Hendrich Fall Risk Model, an instrument to identify patients in a hospital setting with a high risk of falling. Background. Falls are a serious problem in older patients. Valid and reliable fall risk assessment tools are required to identify high-risk patients and to take adequate preventive measures. Methods. Seventy older patients were independently and simultaneously assessed by six pairs of raters made up of nursing staff members. Consensus estimates were calculated using simple percentage agreement and consistency estimates using Spearman's rho and intra class coefficient. Results. Percentage agreement ranged from 0.70 to 0.92 between the six pairs of raters. Spearman's rho coefficients were between 0.54 and 0.80 and the intra class coefficients were between 0.46 and 0.92. Conclusions. Whereas some pairs of raters obtained considerable interobserver agreement and internal consistency, the others did not. Therefore, it is concluded that the Hendrich Fall Risk Model is not a reliable instrument. The use of more unambiguous operationalized items is preferred. Relevance to clinical practice. In practice, well operationalized fall risk assessment tools are necessary. Observer agreement should always be investigated after introducing a standardized measurement tool. © 2008 The Authors. Journal compilation © 2008 Blackwell Publishing Ltd.
Doronina-Amitonova, L. V.; Fedotov, I. V.; Ivashkina, O. I.; Zots, M. A.; Fedotov, A. B.; Anokhin, K. V.; Zheltikov, A. M.
2013-01-01
Seeing the big picture of functional responses within large neural networks in a freely functioning brain is crucial for understanding the cellular mechanisms behind the higher nervous activity, including the most complex brain functions, such as cognition and memory. As a breakthrough toward meeting this challenge, implantable fiber-optic interfaces integrating advanced optogenetic technologies and cutting-edge fiber-optic solutions have been demonstrated, enabling a long-term optogenetic manipulation of neural circuits in freely moving mice. Here, we show that a specifically designed implantable fiber-optic interface provides a powerful tool for parallel long-term optical interrogation of distinctly separate, functionally different sites in the brain of freely moving mice. This interface allows the same groups of neurons lying deeply in the brain of a freely behaving mouse to be reproducibly accessed and optically interrogated over many weeks, providing a long-term dynamic detection of genome activity in response to a broad variety of pharmacological and physiological stimuli. PMID:24253232