Science.gov

Sample records for gallery walk questions

  1. Promoting Discussion in the Science Classroom Using Gallery Walks

    ERIC Educational Resources Information Center

    Francek, Mark

    2006-01-01

    A gallery walk is a discussion technique that gets students out of their chairs and actively involved in synthesizing important science concepts, writing, and public speaking. The technique also cultivates listening and team-building skills. This paper provides guidance for conducting, managing, and assessing gallery walks. (Contains 4 tables and…

  2. Walk, Look, Remember: The Influence of the Gallery's Spatial Layout on Human Memory for an Art Exhibition.

    PubMed

    Krukar, Jakub

    2014-09-01

    The spatial organisation of museums and its influence on the visitor experience has been the subject of numerous studies. Previous research, despite reporting some actual behavioural correlates, rarely had the possibility to investigate the cognitive processes of the art viewers. In the museum context, where spatial layout is one of the most powerful curatorial tools available, attention and memory can be measured as a means of establishing whether or not the gallery fulfils its function as a space for contemplating art. In this exploratory experiment, 32 participants split into two groups explored an experimental, non-public exhibition and completed two unanticipated memory tests afterwards. The results show that some spatial characteristics of an exhibition can inhibit the recall of pictures and shift the focus to perceptual salience of the artworks. PMID:25379276

  3. Image Gallery

    MedlinePlus

    ... R S T U V W X Y Z Image Gallery Share: The Image Gallery contains high-quality digital photographs available from ... Select a category below to view additional thumbnail images. Images are available for direct download in 2 ...

  4. Beyond the Gallery: Interactions between Audiences, Artists, and Their Art through the Kampala Art Tour 2007-2010

    ERIC Educational Resources Information Center

    Nagawa, Margaret

    2012-01-01

    When one walks into an art gallery in Kampala, the capital city of Uganda, one sees a predominantly non-Ugandan audience. Visitors to homes of Ugandans, even those wealthy enough to afford art, find typically bare walls. This begs broader questions: (1) What is it about the education and presentation of contemporary art that excludes local…

  5. Idiopathic toe walking: to treat or not to treat, that is the question.

    PubMed

    Dietz, Fred; Khunsree, Songsak

    2012-01-01

    The natural history and optimal treatment for idiopathic toe walking are unknown. The literature is full of poorly documented treatment regimens with few even medium term follow up studies. The senior author reports his nearly 30 year approach to this disorder and his failed attempt to perform a follow up study of his particular treatment regimen. We conclude with our considered interpretation of the present state of knowledge about idiopathic toe walking and our treatment opinions. PMID:23576939

  6. Heritage Gallery

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Marshall Space Flight Center's (MSFC's) building 4200 hosts a new spaceflight history museum referred to as the Heritage Gallery, allowing employees and visitors alike to have the opportunity to experience history first hand. On display are many models of launch vehicles and spacecraft that have made the center famous. It features a full-scale mockup of the lunar roving vehicle, three built-in multimedia displays, a large theater screen, and two glass cases that house memorabilia such as personal items belonging to Wernher von Braun, MSFC's first Center Director. The new Heritage Gallery features the accomplishments of several past and present members of the Marshall team. Attending the ribbon cutting ceremony are: (left to right) Gerhard Reisig; Cort Durocher, executive director of the American Institute of Aeronautics and Astronautics; Ernst Stuhlinger; Konrad Darnenburg; Werner Dahm; Walter Jacobi; and host of event, Center Director Art Stephenson.

  7. Radical Questioning on the Long Walk to Freedom: Nelson Mandela and the Practice of Critical Reflection

    ERIC Educational Resources Information Center

    Brookfield, Stephen

    2008-01-01

    Nelson Mandela's autobiography "The Long Walk to Freedom" describes how an iconic political activist and freedom fighter reflected on, and sometimes modified, four core assumptions at the heart of his struggle to overturn the White supremacist, minority hegemony and create a free South Africa. Critical reflection's focus is on understanding the…

  8. Questions

    ERIC Educational Resources Information Center

    Kuntz, Haley

    2007-01-01

    A canoe trip guide for young people gets used to the never-ending flow of questions. Kids are constantly inquiring about how many kilometres have been traveled that day, how many kilometres to go that day, what is for dinner, and when the next set of moving water is coming up. With kids, the questions are endless. Questions often are used as a…

  9. Sixth-Grade Gallery Project.

    ERIC Educational Resources Information Center

    Clem, Frances

    2003-01-01

    Describes how an instructional assistant organized a gallery project that featured artwork from the school's staff. Discusses how the gallery was organized, why it was created, and what happened when the students visited it. States that the students selected an artwork as inspiration for a story. (CMK)

  10. Whispering gallery mode sensors

    PubMed Central

    Foreman, Matthew R.; Swaim, Jon D.; Vollmer, Frank

    2015-01-01

    We present a comprehensive overview of sensor technology exploiting optical whispering gallery mode (WGM) resonances. After a short introduction we begin by detailing the fundamental principles and theory of WGMs in optical microcavities and the transduction mechanisms frequently employed for sensing purposes. Key recent theoretical contributions to the modeling and analysis of WGM systems are highlighted. Subsequently we review the state of the art of WGM sensors by outlining efforts made to date to improve current detection limits. Proposals in this vein are numerous and range, for example, from plasmonic enhancements and active cavities to hybrid optomechanical sensors, which are already working in the shot noise limited regime. In parallel to furthering WGM sensitivity, efforts to improve the time resolution are beginning to emerge. We therefore summarize the techniques being pursued in this vein. Ultimately WGM sensors aim for real-world applications, such as measurements of force and temperature, or alternatively gas and biosensing. Each such application is thus reviewed in turn, and important achievements are discussed. Finally, we adopt a more forward-looking perspective and discuss the outlook of WGM sensors within both a physical and biological context and consider how they may yet push the detection envelope further. PMID:26973759

  11. MoMLA: From Panel to Gallery

    ERIC Educational Resources Information Center

    Vitanza, Victor, Ed.; Kuhn, Virginia, Ed.

    2013-01-01

    The work presented here in this "Panel to Gallery" was originally produced and assembled for the 2012 Modern Language Association Conference in Seattle, Washington. Similar to "From Gallery to Webtext", the event Victor curated for the 2006 College Composition and Communication Conference, this "Panel to Gallery" event at MLA set aside the…

  12. Walking Problems

    MedlinePlus

    ... daily activities, get around, and exercise. Having a problem with walking can make daily life more difficult. ... walk is called your gait. A variety of problems can cause an abnormal gait and lead to ...

  13. Walking the walk

    SciTech Connect

    Butler, B.

    1994-12-31

    Earth Day, celebrated this April, brought out a spate of press conferences, fairs and media spots. The White House announced its plans to green itself by incorporating energy efficiency and recycling, and Vice President Gore and Energy Secretary O`Leary announced the President`s Executive Order, which mandates the use of energy efficiency in federal facilities with solar as a high-profile option. At the White House itself, however, no solar application has yet been selected for installation. Another Earth Day media spot showed how the nation`s utility companies have joined Secretary O`Leary`s Climate Challenge, an ambitious voluntary program to cut greenhouse-gas emissions. During Earth Day 1994, it became clear how many houses use solar water heating and how often photovoltaics is used to power road signs and sign boards, telephones and repeaters, and for cathodic protection and security lighting. Solar energy is expanding. But if it is to become a truly everyday technology, more institution, governments, businesses and individual consumers are going to have to walk the walk. This means that Earth Day will have to last longer, environmental concerns must become more genuine, and the focus of government and business decisions must be more long-term.

  14. Deterministic Walks with Choice

    SciTech Connect

    Beeler, Katy E.; Berenhaut, Kenneth S.; Cooper, Joshua N.; Hunter, Meagan N.; Barr, Peter S.

    2014-01-10

    This paper studies deterministic movement over toroidal grids, integrating local information, bounded memory and choice at individual nodes. The research is motivated by recent work on deterministic random walks, and applications in multi-agent systems. Several results regarding passing tokens through toroidal grids are discussed, as well as some open questions.

  15. Genome walking.

    PubMed

    Shapter, Frances M; Waters, Daniel L E

    2014-01-01

    Genome walking is a method for determining the DNA sequence of unknown genomic regions flanking a region of known DNA sequence. The Genome walking has the potential to capture 6-7 kb of sequence in a single round. Ideal for identifying gene promoter regions where only the coding region. Genome walking also has significant utility for capturing homologous genes in new species when there are areas in the target gene with strong sequence conservation to the characterized species. The increasing use of next-generation sequencing technologies will see the principles of genome walking adapted to in silico methods. However, for smaller projects, PCR-based genome walking will remain an efficient method of characterizing unknown flanking sequence. PMID:24243201

  16. Walking Perception by Walking Observers

    ERIC Educational Resources Information Center

    Jacobs, Alissa; Shiffrar, Maggie

    2005-01-01

    People frequently analyze the actions of other people for the purpose of action coordination. To understand whether such self-relative action perception differs from other-relative action perception, the authors had observers either compare their own walking speed with that of a point-light walker or compare the walking speeds of 2 point-light…

  17. Graded-index whispering gallery mode resonators

    NASA Technical Reports Server (NTRS)

    Savchenkov, Anatoliy (Inventor); Maleki, Lutfollah (Inventor); Ilchenko, Vladimir (Inventor); Matsko, Andrey B. (Inventor)

    2005-01-01

    Whispering gallery mode optical resonators which have spatially-graded refractive indices. In one implementation, the refractive index spatially increases with a distance from an exterior surface of such a resonator towards an interior of the resonator to produce substantially equal spectral separations for different whispering gallery modes. An optical coupler may be used with such a resonator to provide proper optical coupling.

  18. Guards, Galleries, Fortresses, and the Octoplex

    ERIC Educational Resources Information Center

    Michael, T. S.

    2011-01-01

    The art gallery problem asks for the maximum number of stationary guards required to protect the interior of a polygonal art gallery with "n" walls. This article explores solutions to this problem and several of its variants. In addition, some unsolved problems involving the guarding of geometric objects are presented.

  19. Questioning the Questions

    ERIC Educational Resources Information Center

    Tienken, Christopher H.; Goldberg, Stephanie; DiRocco, Dominic

    2010-01-01

    Historical accounts of questioning used in the education process trace back to Socrates. One of the best examples of his use of questioning is found in Plato's "The Republic." Socrates used a series of strategic questions to help his student Glaucon come to understand the concept of justice. Socrates purposefully posed a series of questions to…

  20. Nonlinear optical whispering gallery mode resonators

    NASA Technical Reports Server (NTRS)

    Ilchenko, Vladimir (Inventor); Matsko, Andrey B. (Inventor); Savchenkov, Anatoliy (Inventor); Maleki, Lutfollah (Inventor)

    2005-01-01

    Whispering gallery mode (WGM) optical resonators comprising nonlinear optical materials, where the nonlinear optical material of a WGM resonator includes a plurality of sectors within the optical resonator and nonlinear coefficients of two adjacent sectors are oppositely poled.

  1. Whispering-gallery-mode-based seismometer

    SciTech Connect

    Fourguette, Dominique Claire; Otugen, M Volkan; Larocque, Liane Marie; Ritter, Greg Aan; Meeusen, Jason Jeffrey; Ioppolo, Tindaro

    2014-06-03

    A whispering-gallery-mode-based seismometer provides for receiving laser light into an optical fiber, operatively coupling the laser light from the optical fiber into a whispering-gallery-mode-based optical resonator, operatively coupling a spring of a spring-mass assembly to a housing structure; and locating the whispering-gallery-mode-based optical resonator between the spring-mass assembly and the housing structure so as to provide for compressing the whispering-gallery-mode-based optical resonator between the spring-mass assembly and the housing structure responsive to a dynamic compression force from the spring-mass assembly responsive to a motion of the housing structure relative to an inertial frame of reference.

  2. Drawing at the Albright-Knox Gallery.

    ERIC Educational Resources Information Center

    Blume, Sharon

    1982-01-01

    Describes the Advanced Drawing Studio for talented students at the Albright-Knox Gallery in Buffalo, NY. The program's purpose is to improve students' drawing skills and increase their ability to look at and appreciate abstract art. (AM)

  3. Quantum random walks without walking

    SciTech Connect

    Manouchehri, K.; Wang, J. B.

    2009-12-15

    Quantum random walks have received much interest due to their nonintuitive dynamics, which may hold the key to a new generation of quantum algorithms. What remains a major challenge is a physical realization that is experimentally viable and not limited to special connectivity criteria. We present a scheme for walking on arbitrarily complex graphs, which can be realized using a variety of quantum systems such as a Bose-Einstein condensate trapped inside an optical lattice. This scheme is particularly elegant since the walker is not required to physically step between the nodes; only flipping coins is sufficient.

  4. Whispering Gallery Mode Optomechanical Resonator

    NASA Technical Reports Server (NTRS)

    Aveline, David C.; Strekalov, Dmitry V.; Yu, Nan; Yee, Karl Y.

    2012-01-01

    Great progress has been made in both micromechanical resonators and micro-optical resonators over the past decade, and a new field has recently emerged combining these mechanical and optical systems. In such optomechanical systems, the two resonators are strongly coupled with one influencing the other, and their interaction can yield detectable optical signals that are highly sensitive to the mechanical motion. A particularly high-Q optical system is the whispering gallery mode (WGM) resonator, which has many applications ranging from stable oscillators to inertial sensor devices. There is, however, limited coupling between the optical mode and the resonator s external environment. In order to overcome this limitation, a novel type of optomechanical sensor has been developed, offering great potential for measurements of displacement, acceleration, and mass sensitivity. The proposed hybrid device combines the advantages of all-solid optical WGM resonators with high-quality micro-machined cantilevers. For direct access to the WGM inside the resonator, the idea is to radially cut precise gaps into the perimeter, fabricating a mechanical resonator within the WGM. Also, a strategy to reduce losses has been developed with optimized design of the cantilever geometry and positions of gap surfaces.

  5. Questioning the Questions

    ERIC Educational Resources Information Center

    Tienken, Christopher H.; Goldberg, Stephanie; DiRocco, Dominic

    2009-01-01

    Well-known historical accounts of questioning used in the education process trace back to Socrates. One of the best examples of his use of questioning is found in Plato's classic work "The Republic" (2003). Today, teachers still use questions as one way to help students develop productive thinking skills and to understand concepts and topics.…

  6. Landslide Caused Damages in a Gallery

    NASA Astrophysics Data System (ADS)

    Poisel, R.; Mair am Tinkhof, K.; Preh, A.

    2016-06-01

    On October 5th, 2010, cracks were found in a gallery 1.8 m high and 1.4 m wide. The gallery is 100 years old, runs parallel to a valley flank and was excavated in a tectonically strongly stressed, weathered and slightly dipping sandwich of clayey shales, sandstones and marls. The cracks in the roof as well as in the invert ran parallel to the axis of the gallery. Monitoring showed that crack widths were increasing 1.5 mm per year, sidewall distances were increasing 3.5 mm per year, whereas the height of the gallery was decreasing 2.5 mm per year. After eliminating several possible causes of cracking, a landslide producing the damages had to be taken into consideration. Monitoring of the valley flank surface as well as inclinometer readings revealed that a landslide was occurring, loading the gallery lining. Most probably the landslide had been reactivated by excessive rainfall in 2009 as well as by works for the renewal of a weir in the valley bottom. As stabilization of the slope was not an option for several reasons, it was decided to replace the gallery by a new one deeper inside the slope, which will be ready for operation in 2017. Thus the old gallery has to be kept in operation till then and it was decided to reinforce the old gallery by a heavily reinforced shotcrete lining 10 cm thick. As slope displacements went on, cracks in the shotcrete lining developed with a completely different pattern: in the section where the gallery lies completely in the landslide shear zone no cracks formed until now due to heavy reinforcement, whereas in the transition sections stable ground-landslide and landslide-stable ground diagonal tension cracks in the roof due to shear by the landslide developed. Numerical models showed that cracking and spalling of the shotcrete lining would occur only after some centimetres of additional displacements of the slope, which hopefully will not occur before 2017.

  7. At 1150 Gallery, Block 5, view of spiral stairway leading ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    At 1150 Gallery, Block 5, view of spiral stairway leading to 1200 Gallery, looking south. - Columbia Basin Project, Grand Coulee Dam & Franklin D. Roosevelt Lake, Across Columbia River, Southeast of Town of Grand Coulee, Grand Coulee, Grant County, WA

  8. 7. Historic American Building Survey Crocker Art Gallery Collection Stero ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Historic American Building Survey Crocker Art Gallery Collection Stero Photo of 1875 Rephoto 1960 INTERIOR STAIRHALL MAIN FLOOR TO WEST - Crocker Art Gallery, 216 O Street, Sacramento, Sacramento County, CA

  9. 13. Historic American Building Survey Crocker Art Gallery Collection Original ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. Historic American Building Survey Crocker Art Gallery Collection Original 1875 Rephoto 1960 DINING ROOM (IN SERVICE WING) LOOKING EAST TO HALL & DOUBLE PARLOURS - Crocker Art Gallery, 216 O Street, Sacramento, Sacramento County, CA

  10. "Menage a Trois": The University, Art Gallery, and the Schools.

    ERIC Educational Resources Information Center

    Evans, Jane Turnbull

    1984-01-01

    The Mackenzie Art Gallery in Regina, Saskatchewan, Canada, provides an internship program for students enrolled in the art education program at the University of Regina. The gallery trains teachers in the concepts of aesthetic education and the use of art objects and gallery resources in the teaching of those concepts. (RM)

  11. Portrait Gallery Illuminates--Grant's Triumphs, Failures.

    ERIC Educational Resources Information Center

    Lambert, Robert G., Jr.

    The 100th anniversary of Ulysses S. Grant's death was observed on July 23, 1985. The Smithsonian National Portrait Gallery featured an exhibit of Grant portraiture, which covered his life, from its humble beginnings to military and political triumphs and to failures and disappointment. The exhibit included pictures, artifacts, and momentos from…

  12. Shooting Gallery Notes. Working Paper #22. Preliminary.

    ERIC Educational Resources Information Center

    Bourgois, Philippe

    This paper contains ethnographic participant-observation field notes taken on a one-night visit to a "shooting gallery" in East Harlem (New York City) along with background information and commentary. East Harlem, also referred to as "El Barrio" or Spanish Harlem, is a 200-square block neighborhood on the upper East Side of Manhattan in New York…

  13. The Empirical Spectator and Gallery Education

    ERIC Educational Resources Information Center

    Fulkova, Marie; Straker, Alison; Jaros, Milan

    2004-01-01

    This paper examines the onto-epistemic status and understanding of contemporary material culture and of visual art, particularly in the context of gallery education. It does so through a case study of the response of 15 year-old school students in the Czech Republic and in England to a recent photographic exhibition, I.N.R.I., created by artists…

  14. Gallery of ESOL Lesson Plans.

    ERIC Educational Resources Information Center

    Literacy Assistance Center, New York, NY.

    This collection of lesson plans for teaching English as a Second Language includes the following: "You Scratched Me!" which has students examine verbs in three forms (base, past, and progressive) together with questions, accelerating the memorization and understanding of verb forms and tenses; "Getting Acquainted/Inferential Thinking," which…

  15. Complementarity and quantum walks

    SciTech Connect

    Kendon, Viv; Sanders, Barry C.

    2005-02-01

    We show that quantum walks interpolate between a coherent 'wave walk' and a random walk depending on how strongly the walker's coin state is measured; i.e., the quantum walk exhibits the quintessentially quantum property of complementarity, which is manifested as a tradeoff between knowledge of which path the walker takes vs the sharpness of the interference pattern. A physical implementation of a quantum walk (the quantum quincunx) should thus have an identifiable walker and the capacity to demonstrate the interpolation between wave walk and random walk depending on the strength of measurement.

  16. Single molecules as whispering galleries for electrons

    NASA Astrophysics Data System (ADS)

    Reecht, G.; Bulou, H.; Schull, G.; Scheurer, F.

    2016-04-01

    Whispering gallery modes, well-known for acoustic and optical waves, have been shown recently for electrons in molecules on surfaces. The existence of such waves opens new possibilities for nanoelectronic devices. Here we propose a simple analytical textbook model which allows the main characteristic features of such electronic waves to be understood. The model is illustrated by two- and three-dimensional experimental situations.

  17. Single molecules as whispering galleries for electrons.

    PubMed

    Reecht, G; Bulou, H; Schull, G; Scheurer, F

    2016-04-27

    Whispering gallery modes, well-known for acoustic and optical waves, have been shown recently for electrons in molecules on surfaces. The existence of such waves opens new possibilities for nanoelectronic devices. Here we propose a simple analytical textbook model which allows the main characteristic features of such electronic waves to be understood. The model is illustrated by two- and three-dimensional experimental situations. PMID:26987969

  18. Fire-walking

    NASA Astrophysics Data System (ADS)

    Willey, David

    2010-09-01

    This article gives a brief history of fire-walking and then deals with the physics behind fire-walking. The author has performed approximately 50 fire-walks, took the data for the world's hottest fire-walk and was, at one time, a world record holder for the longest fire-walk (www.dwilley.com/HDATLTW/Record_Making_Firewalks.html). He currently teaches Physics for the University of Pittsburgh at Johnstown, USA.

  19. Fire-Walking

    ERIC Educational Resources Information Center

    Willey, David

    2010-01-01

    This article gives a brief history of fire-walking and then deals with the physics behind fire-walking. The author has performed approximately 50 fire-walks, took the data for the world's hottest fire-walk and was, at one time, a world record holder for the longest fire-walk (www.dwilley.com/HDATLTW/Record_Making_Firewalks.html). He currently…

  20. Possible methods of reconstructing conveyor gallery span structures

    SciTech Connect

    Kolesnichenko, V.G.; Beizer, V.N.; Raskina, A.M.

    1983-01-01

    Problems of reconstruction of industrial buildings and structures are acquiring increasing national economic importance. The Makeevka Construction Engineering Institute of the conducted investigations of the design of the conveyor galleries at the Yasinovka and Makeevka Coke Works, in operation for 20-40 years. The bearing constructions of the span structures are generally welded (in the old galleries riveted) metal trusses. The principal trusses are predominantly made discontinuous with spans of 10-40 m, supported by hinges on intermediate lattice columns, connected through the upper and lower horizontal strips by ties (see figure, a). The height of the main trusses corresponds to the height of the galleries (2.3-3.4 m). The width of a gallery depends on the width and number of conveyors; for galleries with a single conveyor it is 3.1-3.8 m, and 5.5-7.1 m for a gallery with two conveyors.

  1. 18. INTERIOR OF CIVIL RIGHTS INSTITUTE, MILESTONE GALLERY EXHIBITION OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    18. INTERIOR OF CIVIL RIGHTS INSTITUTE, MILESTONE GALLERY EXHIBITION OF THE SIXTEENTH STREET CHURCH, LOOKING NORTHWEST - Sixteenth Street Baptist Church, 1530 Sixth Avenue North, Birmingham, Jefferson County, AL

  2. Cognitive Resource Demands of Redirected Walking.

    PubMed

    Bruder, Gerd; Lubas, Paul; Steinicke, Frank

    2015-04-01

    Redirected walking allows users to walk through a large-scale immersive virtual environment (IVE) while physically remaining in a reasonably small workspace. Therefore, manipulations are applied to virtual camera motions so that the user's self-motion in the virtual world differs from movements in the real world. Previous work found that the human perceptual system tolerates a certain amount of inconsistency between proprioceptive, vestibular and visual sensation in IVEs, and even compensates for slight discrepancies with recalibrated motor commands. Experiments showed that users are not able to detect an inconsistency if their physical path is bent with a radius of at least 22 meters during virtual straightforward movements. If redirected walking is applied in a smaller workspace, manipulations become noticeable, but users are still able to move through a potentially infinitely large virtual world by walking. For this semi-natural form of locomotion, the question arises if such manipulations impose cognitive demands on the user, which may compete with other tasks in IVEs for finite cognitive resources. In this article we present an experiment in which we analyze the mutual influence between redirected walking and verbal as well as spatial working memory tasks using a dual-tasking method. The results show an influence of redirected walking on verbal as well as spatial working memory tasks, and we also found an effect of cognitive tasks on walking behavior. We discuss the implications and provide guidelines for using redirected walking in virtual reality laboratories. PMID:26357104

  3. ASPRS Digital Imagery Guideline Image Gallery Discussion

    NASA Technical Reports Server (NTRS)

    Ryan, Robert

    2002-01-01

    The objectives of the image gallery are to 1) give users and providers a simple means of identifying appropriate imagery for a given application/feature extraction; and 2) define imagery sufficiently to be described in engineering and acquisition terms. This viewgraph presentation includes a discussion of edge response and aliasing for image processing, and a series of images illustrating the effects of signal to noise ratio (SNR) on images. Another series of images illustrates how images are affected by varying the ground sample distances (GSD).

  4. Magnetic whispering-gallery mirror for atoms

    NASA Astrophysics Data System (ADS)

    Bertram, R. P.; Merimeche, H.; Mützel, M.; Metcalf, H.; Haubrich, D.; Meschede, D.; Rosenbusch, P.; Hinds, E. A.

    2001-05-01

    Videotape with a sinusoidal magnetization of 31 μm wavelength is used to reflect Cs atoms with unit reflectivity in a 75 m/s atomic beam. The atoms serve as a probe, allowing us to measure the magnetic field at the surface. A technique is presented for mounting the videotape so that its surface can be curved to a specific shape or made flexible. We show that such a reflector provides high-quality grazing-incidence atom optics and we demonstrate deflections as large as 23 ° in a whispering-gallery geometry.

  5. Predictors of Walking Performance and Walking Capacity in People with Lumbar Spinal Stenosis, Low Back Pain and Asymptomatic Controls

    PubMed Central

    Tomkins-Lane, Christy C.; Holz, Sara Christensen; Yamakawa, KS; Phalke, Vaishali V.; Quint, Doug J.; Miner, Jennifer; Haig, Andrew J.

    2011-01-01

    Objective Examine predictors of community walking performance and walking capacity in lumbar spinal stenosis (LSS), compared to individuals with low back pain and asymptomatic controls. Design Retrospective analysis. Setting University Spine Program. Participants 126 participants (50 LSS, 44 low back pain and 32 asymptomatic controls), aged 55–80 yrs. Interventions Not applicable. Main Outcome Measure(s) 7-day community walking distance measured by pedometer (walking performance) and a 15 minute walking test (walking capacity). All participants had a lumbosacral MRI, electrodiagnostic testing, and a history and physical examination including history of pain and neurologic symptoms, straight leg raise test, tests for directional symptoms, reflexes, strength, and nerve tension signs. The study questionnaire included demographic information, history of back/leg pain, questions about walking, exercise frequency, and pain level, as well as the standardized Quebec Back Pain Disability Scale. Results BMI, pain, age and female sex predicted walking performance (r2 = 0.41) and walking capacity (r2=0.41). The diagnosis of LSS itself had no clear relationship with either walking variable. Compared to the asymptomatic group, LSS participants had significantly lower values for all walking parameters, with the exception of stride length, while there was no significant difference between the LSS and low back pain groups. Conclusions BMI, pain, female sex, and age predict walking performance and capacity in people with LSS, low back pain, and asymptomatic controls. While pain was the strongest predictor of walking capacity, BMI was the strongest predictor of walking performance. Average pain, rather than leg pain was predictive of walking. Obesity and pain are modifiable predictors of walking deficits that could be targets for future intervention studies aimed at increasing walking performance and capacity in both the low back pain and LSS populations. PMID:22365377

  6. Genesis of a Joint Gallery of Sport Art.

    ERIC Educational Resources Information Center

    Kozar, Andrew J.

    1989-01-01

    The University of Pennsylvania's dual sport art gallery showcases the work of R. Taft McKenzie and Joe Brown, two of the premier sport artists of our time. This article briefly outlines the artists' careers and describes the planning which led to establishment of the gallery. (IAH)

  7. Places to Go: New York Public Library Digital Gallery

    ERIC Educational Resources Information Center

    Downes, Stephen

    2005-01-01

    This article features the New York Public Library's (NYPL) recently opened Digital Gallery. Containing more than 275,000 images digitized from primary sources and printed rarities, the Digital Gallery offers unparalleled access to the past for educators and interested visitors alike. Organization and navigation present a challenge with any…

  8. Reconfigurable Optical Spectra from Perturbations on Elliptical Whispering Gallery Resonances

    NASA Technical Reports Server (NTRS)

    Mohageg, Makan; Maleki, Lute

    2008-01-01

    Elastic strain, electrical bias, and localized geometric deformations were applied to elliptical whispering-gallery-mode resonators fabricated with lithium niobate. The resultant perturbation of the mode spectrum is highly dependant on the modal indices, resulting in a discretely reconfigurable optical spectrum. Breaking of the spatial degeneracy of the whispering-gallery modes due to perturbation is also observed.

  9. View just east of Block 31, 1150 Gallery, looking west ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View just east of Block 31, 1150 Gallery, looking west showing change in ceiling height; in foreground is transverse gallery used for drum gate cord storage. - Columbia Basin Project, Grand Coulee Dam & Franklin D. Roosevelt Lake, Across Columbia River, Southeast of Town of Grand Coulee, Grand Coulee, Grant County, WA

  10. 19. Historic American Building Survey Crocker Art Gallery Collection Copy ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    19. Historic American Building Survey Crocker Art Gallery Collection Copy from N. P. Goodell, Architect C1879 NORTHWEST CORNER (EAST ELEVATION?) OF 3RD & P ST. (property of Mrs. E. B. Crocker) - Crocker Art Gallery, 216 O Street, Sacramento, Sacramento County, CA

  11. 20. Historic American Building Survey Crocker Art Gallery Collection Drawing ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    20. Historic American Building Survey Crocker Art Gallery Collection Drawing by N.D. Goodell, Architect C 1879 NORTH ELEVATION, SOUTH HOUSE (Property of Mrs. E. B. Crocker, 3rd & P Sts.) - Crocker Art Gallery, 216 O Street, Sacramento, Sacramento County, CA

  12. At 750 Gallery, (sump level) view of drain to sump ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    At 750 Gallery, (sump level) view of drain to sump pumps, looking north. This level contains the "art gallery" which features graffiti from the 1940s-1990s. - Columbia Basin Project, Grand Coulee Dam & Franklin D. Roosevelt Lake, Across Columbia River, Southeast of Town of Grand Coulee, Grand Coulee, Grant County, WA

  13. From Analog Prototypes to Digital Drawing in the Gallery

    ERIC Educational Resources Information Center

    Nelson, Karen G.

    2011-01-01

    The "You Are Here" digital drawing interactive is one of the most successful interpretive elements in the renovated Oakland Museum of California Gallery of California Art. This interactive grew from considering how visitors could see themselves in the gallery and how visitor awareness of the creative process could be increased. The renovation…

  14. Detecting light in whispering-gallery-mode resonators

    NASA Technical Reports Server (NTRS)

    Savchenkov, Anatoliy (Inventor); Maleki, Lutfollah (Inventor); Mohageg, Makan (Inventor); Le, Thanh M. (Inventor)

    2012-01-01

    An optical device including a whispering gallery mode (WGM) optical resonator configured to support one or more whispering gallery modes; and a photodetector optically coupled to an exterior surface of the optical resonator to receive evanescent light from the optical resonator to detect light inside the optical resonator.

  15. View north of west gallery of inside machine shop 36; ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View north of west gallery of inside machine shop 36; the gallery housed turret, engine and toolroom lathes, small milling machines and drill presses used for machining small parts. - Naval Base Philadelphia-Philadelphia Naval Shipyard, Structure Shop, League Island, Philadelphia, Philadelphia County, PA

  16. Reconfigurable optical spectra from perturbations on elliptical whispering gallery resonances.

    PubMed

    Mohageg, Makan; Maleki, Lute

    2008-02-01

    Elastic strain, electrical bias, and localized geometric deformations were applied to elliptical whispering-gallery-mode resonators fabricated with lithium niobate. The resultant perturbation of the mode spectrum is highly dependant on the modal indices, resulting in a discretely reconfigurable optical spectrum. Breaking of the spatial degeneracy of the whispering-gallery modes due to perturbation is also observed. PMID:18542283

  17. Science Outreach through Art: A Journal Article Cover Gallery

    ERIC Educational Resources Information Center

    McCullough, Ian

    2015-01-01

    Research faculty journal covers were used to create a gallery in the Science & Technology branch library at the University of Akron. The selection, presentation, and promotion process is shared along with copyright considerations and a review of galleries used for library outreach. The event and display was a great success attracting faculty…

  18. The Authors Gallery: A Meaningful Integration of Technology and Writing

    ERIC Educational Resources Information Center

    Martin, Deb

    2008-01-01

    In this article, the author first explains what an authors gallery is and suggests additional uses and modifications. Next, readers are taken through a day-by-day description of creating the gallery while having the theory behind this pedagogical choice explained. The step-by-step discussion is supported with student examples and concepts drawn…

  19. Coral Reefs: A Gallery Program, Grades 7-12.

    ERIC Educational Resources Information Center

    National Aquarium in Baltimore, MD. Dept. of Education.

    Gallery classes at the National Aquarium in Baltimore give the opportunity to study specific aquarium exhibits which demonstrate entire natural habitats. The coral reef gallery class features the gigantic western Atlantic coral reef (325,000 gallons) with over 1,000 fish. The exhibit simulates a typical Caribbean coral reef and nearby sandy…

  20. Quantum walk computation

    SciTech Connect

    Kendon, Viv

    2014-12-04

    Quantum versions of random walks have diverse applications that are motivating experimental implementations as well as theoretical studies. Recent results showing quantum walks are “universal for quantum computation” relate to algorithms, to be run on quantum computers. We consider whether an experimental implementation of a quantum walk could provide useful computation before we have a universal quantum computer.

  1. Walk This Way

    ERIC Educational Resources Information Center

    Mason, Nick

    2007-01-01

    A generation ago, it was part of growing up for all kids when they biked or walked to school. But in the last 30 years, heavier traffic, wider roads and more dangerous intersections have made it riskier for students walking or pedaling. Today, fewer than 15 percent of kids bike or walk to school compared with more than 50 percent in 1969. In the…

  2. Walking Wellness. Student Workbook.

    ERIC Educational Resources Information Center

    Sweetgall, Robert; Neeves, Robert

    This comprehensive student text and workbook, for grades four through eight, contains 16 workshop units focusing on walking field trips, aerobic pacing concepts, walking techniques, nutrition, weight control and healthy life-style planning. Co-ordinated homework assignments are included. The appendixes include 10 tips for walking, a calorie chart,…

  3. Walk Score®

    PubMed Central

    Brown, Scott C.; Pantin, Hilda; Lombard, Joanna; Toro, Matthew; Huang, Shi; Plater-Zyberk, Elizabeth; Perrino, Tatiana; Perez-Gomez, Gianna; Barrera-Allen, Lloyd; Szapocznik, José

    2013-01-01

    Background Walk Score® is a nationally and publicly available metric of neighborhood walkability based on proximity to amenities (e.g., retail, food, schools). However, few studies have examined the relationship of Walk Score to walking behavior. Purpose To examine the relationship of Walk Score to walking behavior in a sample of recent Cuban immigrants, who overwhelmingly report little choice in their selection of neighborhood built environments when they arrive in the U.S. Methods Participants were 391 recent healthy Cuban immigrants (M age=37.1 years) recruited within 90 days of arrival in the U.S., and assessed within 4 months of arrival (M=41.0 days in the U.S.), who resided throughout Miami-Dade County FL. Data on participants’ addresses, walking and sociodemographics were collected prospectively from 2008 to 2010. Analyses conducted in 2011 examined the relationship of Walk Score for each participant’s residential address in the U.S. to purposive walking, controlling for age, gender, education, BMI, days in the U.S., and habitual physical activity level in Cuba. Results For each 10-point increase in Walk Score, adjusting for covariates, there was a significant 19% increase in the likelihood of purposive walking, a 26% increase in the likelihood of meeting physical activity recommendations by walking, and 27% more minutes walked in the previous week. Conclusions Results suggest that Walk Score is associated with walking in a sample of recent immigrants who initially had little choice in where they lived in the U.S. These results support existing guidelines indicating that mixed land use (such as parks and restaurants near homes) should be included when designing walkable communities. PMID:23867028

  4. Questioning Techniques.

    ERIC Educational Resources Information Center

    Patterson, Michelle

    1999-01-01

    Questions are so much a part of the classroom routine and they should stimulate learning and thinking. Introduces the Questioning and Understanding to Improve Learning and Thinking (QUILT) method which incorporates Bloom's Taxonomy and wait time. (ASK)

  5. Infant Language Development Is Related to the Acquisition of Walking

    ERIC Educational Resources Information Center

    Walle, Eric A.; Campos, Joseph J.

    2014-01-01

    The present investigation explored the question of whether walking onset is related to infant language development. Study 1 used a longitudinal design (N = 44) to assess infant locomotor and language development every 2 weeks from 10 to 13.5 months of age. The acquisition of walking was associated with a significant increase in both receptive and…

  6. Aptasensors Based on Whispering Gallery Mode Resonators.

    PubMed

    Nunzi Conti, Gualtiero; Berneschi, Simome; Soria, Silvia

    2016-01-01

    In this paper, we review the literature on optical evanescent field sensing in resonant cavities where aptamers are used as biochemical receptors. The combined advantages of highly sensitive whispering gallery mode resonator (WGMR)-based transducers, and of the unique properties of aptamers make this approach extremely interesting in the medical field, where there is a particularly high need for devices able to provide real time diagnosis for cancer, infectious diseases, or strokes. However, despite the superior performances of aptamers compared to antibodies and WGMR to other evanescent sensors, there is not much literature combining both types of receptors and transducers. Up to now, the WGMR that have been used are silica microspheres and silicon oxynitride (SiON) ring resonators. PMID:27438861

  7. Whispering gallery effects in the troposphere

    NASA Astrophysics Data System (ADS)

    Hitney, Herbert V.

    1992-12-01

    Experimental data that recorded higher-than-expected signals at 3087.7 MHz far beyond the horizon in the presence of an elevated duct are examined and compared to results from the radio physical optics (RPO) propagation model. RPO is a range-dependent hybrid model that combines ray optics and parabolic equation methods. Previous modeling of this same case study using waveguide methods for both the measured elevated duct and hypothetical evaporation ducts has been disappointing. However, when the elevated duct is allowed to rise slowly with increasing range, the RPO results closely match the observed signal levels, indicating that weakly attenuated earth-detached, or whispering gallery, modes were the dominant propagation mechanism.

  8. Whispering-Gallery Mode-Locked Lasers

    NASA Technical Reports Server (NTRS)

    Matsko, Andrey; Iltchenko, Vladimir; Savchenkov, Anatoly; Maleki, Lute

    2003-01-01

    Mode-locked lasers of a proposed type would incorporate features of the design and operation of previously demonstrated miniature electro-optical modulators and erbium-doped glass lasers that contain whispering-gallery-mode (WGM) resonators. That is to say, WGM lasers and WGM electro-optical modulators would be integrated into monolithic units that, when suitably excited with pump light and microwaves, would function as mode-locked lasers. The proposed devices are intended to satisfy an anticipated demand for compact, low-power devices that could operate in the optical-communication wavelength band centered at a wavelength of 1.55 m and could generate pulses as short as picoseconds at repetition rates of multiple gigahertz.

  9. Critiquing Questions

    ERIC Educational Resources Information Center

    Zimmerman, Lynn W.

    2015-01-01

    Question formation is a basic part of teaching and learning English. However, teachers often focus on the ability to form the question properly and not as much on the quality of the information the question is seeking. Whether teaching English language learners or students who want to be English teachers, teachers need to carefully consider the…

  10. Four Questions

    ERIC Educational Resources Information Center

    Hark-Weber, Amara G., Ed.

    2013-01-01

    The author is pleased to introduce a new section in "TAJ," Four Questions. The structure is simple: four questions are asked to teaching artists working in various media and locations. The questions are always the same, but because each teaching artist's approach is unique, their answers will provide an insight into particular methodologies that…

  11. 74. Credit TCL. General overview of interior from gallery looking ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    74. Credit TCL. General overview of interior from gallery looking east. Note air duct on generator (now removed). - Battle Creek Hydroelectric System, Battle Creek & Tributaries, Red Bluff, Tehama County, CA

  12. 72. Credit FM. Overview of powerhouse from gallery. Notice cooling ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    72. Credit FM. Overview of powerhouse from gallery. Notice cooling duct on generator (now removed) and spare gate valve in far corner. - Battle Creek Hydroelectric System, Battle Creek & Tributaries, Red Bluff, Tehama County, CA

  13. 16. VIEW OF FIRST FLOOR EAST OPERATING GALLERY. NOTE THE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    16. VIEW OF FIRST FLOOR EAST OPERATING GALLERY. NOTE THE SERIES OF MANIPULATOR ARMS ALONG THE LEFT WALL. - Nevada Test Site, Engine Maintenance Assembly & Disassembly Facility, Area 25, Jackass Flats, Mercury, Nye County, NV

  14. 10. VIEW WITHIN THE EAST OPERATING GALLERY OF WORK STATION ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. VIEW WITHIN THE EAST OPERATING GALLERY OF WORK STATION WITH MANIPULATOR ARMS. - Nevada Test Site, Engine Maintenance Assembly & Disassembly Facility, Area 25, Jackass Flats, Mercury, Nye County, NV

  15. 14. VIEW IN THE WEST OPERATING GALLERY OF POSTMORTEM CELL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. VIEW IN THE WEST OPERATING GALLERY OF POST-MORTEM CELL WORK STATION AND MANIPULATOR ARMS. - Nevada Test Site, Engine Maintenance Assembly & Disassembly Facility, Area 25, Jackass Flats, Mercury, Nye County, NV

  16. 5. JL photographer, summer 1978. View in filteration gallery looking ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. JL photographer, summer 1978. View in filteration gallery looking to filter pits. - Division Avenue Pumping Station & Filtration Plant, West 45th Street and Division Avenue, Cleveland, Cuyahoga County, OH

  17. 7. Detail of gallery railings, looking north along Saybrook east ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Detail of gallery railings, looking north along Saybrook east breakwater to Lynde Point Lighthouse - Saybrook Breakwater Light, South tip of west end of Saybrook Breakwater, Old Saybrook, Middlesex County, CT

  18. VIEW WESTBUILDING 7 MACHINE SHOP (1901 SECTIONNORTH GALLERY) John ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW WEST-BUILDING 7 MACHINE SHOP (1901 SECTION-NORTH GALLERY) - John A. Roebling's Sons Company & American Steel & Wire Company, South Broad, Clark, Elmer, Mott & Hudson Streets, Trenton, Mercer County, NJ

  19. 8. INTERIOR VIEW, LOOKING SOUTH, OF MUSEUM GALLERY WITH EUGENE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. INTERIOR VIEW, LOOKING SOUTH, OF MUSEUM GALLERY WITH EUGENE ALLEN SMITH'S VEHICLE WITH WHICH HE AS STATE GEOLOGIST (FROM 1873 TO 1927) CONDUCTED SURVEYS OF DISTRICT MINERAL RESOURCES - Smith Hall, Capstone Drive at Sixth Avenue, Tuscaloosa, Tuscaloosa County, AL

  20. Nonlinear optics and crystalline whispering gallery mode resonators

    NASA Technical Reports Server (NTRS)

    Matsko, Andrey; Savchenkov, Anatoliy; Ilchenko, Vladimir S.; Maleki, Lute

    2004-01-01

    We report on our recent results concerning fabrication of high-Q whispering gallery mode crystalline resonaors, and discuss some possible applications of lithium niobate WGM resonators in nonlinear optics and photonics.

  1. At 1150 Gallery, Block 5, view of top of spiral ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    At 1150 Gallery, Block 5, view of top of spiral stairway, looking west. - Columbia Basin Project, Grand Coulee Dam & Franklin D. Roosevelt Lake, Across Columbia River, Southeast of Town of Grand Coulee, Grand Coulee, Grant County, WA

  2. At 1150 Gallery, Block 5, between spiral stairways, looking southwest. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    At 1150 Gallery, Block 5, between spiral stairways, looking southwest. - Columbia Basin Project, Grand Coulee Dam & Franklin D. Roosevelt Lake, Across Columbia River, Southeast of Town of Grand Coulee, Grand Coulee, Grant County, WA

  3. At 1150 Gallery, Block 7, looking east, the length of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    At 1150 Gallery, Block 7, looking east, the length of the dam. - Columbia Basin Project, Grand Coulee Dam & Franklin D. Roosevelt Lake, Across Columbia River, Southeast of Town of Grand Coulee, Grand Coulee, Grant County, WA

  4. Interior hallway at 1250 Gallery, Block 11, which leads from ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior hallway at 1250 Gallery, Block 11, which leads from Left Powerhouse to Pump-Generating Plant, looking southwest. - Columbia Basin Project, Grand Coulee Dam Powerplant Complex, Grand Coulee, Grant County, WA

  5. 41. VALVEHOUSE FOR NEEDLE VALVE OUTLET WORKS ON GALLERY 2, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    41. VALVEHOUSE FOR NEEDLE VALVE OUTLET WORKS ON GALLERY 2, SHOWING NEEDLE VALVE CONTROL PEDESTALS (MANUFACTURED BY AMERICAN LOCOMOTIVE COMPANY) IN LEFT FOREGROUND AND RIGHT BACKGROUND. VIEW TO NORTHEAST. - Owyhee Dam, Across Owyhee River, Nyssa, Malheur County, OR

  6. 43. VALVEHOUSE FOR NEED VALVE OUTLET WORKS ON GALLERY 2, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    43. VALVEHOUSE FOR NEED VALVE OUTLET WORKS ON GALLERY 2, SHOWING CONTROL PEDESTAL IN FOREGROUND AND NEEDLE VALVE AIR VENTS IN CENTER. VIEW TO WEST. - Owyhee Dam, Across Owyhee River, Nyssa, Malheur County, OR

  7. Optical rogue waves in whispering-gallery-mode resonators

    NASA Astrophysics Data System (ADS)

    Coillet, Aurélien; Dudley, John; Genty, Goëry; Larger, Laurent; Chembo, Yanne K.

    2014-01-01

    We report a theoretical study showing that rogue waves can emerge in whispering-gallery-mode resonators as the result of the chaotic interplay between Kerr nonlinearity and anomalous group-velocity dispersion. The nonlinear dynamics of the propagation of light in a whispering-gallery-mode resonator is investigated using the Lugiato-Lefever equation, and we give evidence of a range of parameters where rare and extreme events associated with non-Gaussian statistics of the field maxima are observed.

  8. Whispering Gallery Optical Resonator Spectroscopic Probe and Method

    NASA Technical Reports Server (NTRS)

    Anderson, Mark S. (Inventor)

    2014-01-01

    Disclosed herein is a spectroscopic probe comprising at least one whispering gallery mode optical resonator disposed on a support, the whispering gallery mode optical resonator comprising a continuous outer surface having a cross section comprising a first diameter and a second diameter, wherein the first diameter is greater than the second diameter. A method of measuring a Raman spectrum and an Infra-red spectrum of an analyte using the spectroscopic probe is also disclosed.

  9. Walking training associated with virtual reality-based training increases walking speed of individuals with chronic stroke: systematic review with meta-analysis

    PubMed Central

    Rodrigues-Baroni, Juliana M.; Nascimento, Lucas R.; Ada, Louise; Teixeira-Salmela, Luci F.

    2014-01-01

    OBJECTIVE: To systematically review the available evidence on the efficacy of walking training associated with virtual reality-based training in patients with stroke. The specific questions were: Is walking training associated with virtual reality-based training effective in increasing walking speed after stroke? Is this type of intervention more effective in increasing walking speed, than non-virtual reality-based walking interventions? METHOD: A systematic review with meta-analysis of randomized clinical trials was conducted. Participants were adults with chronic stroke and the experimental intervention was walking training associated with virtual reality-based training to increase walking speed. The outcome data regarding walking speed were extracted from the eligible trials and were combined using a meta-analysis approach. RESULTS: Seven trials representing eight comparisons were included in this systematic review. Overall, the virtual reality-based training increased walking speed by 0.17 m/s (IC 95% 0.08 to 0.26), compared with placebo/nothing or non-walking interventions. In addition, the virtual reality-based training increased walking speed by 0.15 m/s (IC 95% 0.05 to 0.24), compared with non-virtual reality walking interventions. CONCLUSIONS: This review provided evidence that walking training associated with virtual reality-based training was effective in increasing walking speed after stroke, and resulted in better results than non-virtual reality interventions. PMID:25590442

  10. Essential Questions

    ERIC Educational Resources Information Center

    Wilhelm, Jeffrey D.

    2012-01-01

    The secret to teaching may be as simple as asking students good questions--and then giving them the opportunity to find the answers. The author shares how he uses essential questions that set the class off on an inquiry. Rather than consuming information that he distributes and then repeating it on a test, students carry out their own…

  11. Question Mapping

    ERIC Educational Resources Information Center

    Martin, Josh

    2012-01-01

    After accepting the principal position at Farmersville (TX) Junior High, the author decided to increase instructional rigor through question mapping because of the success he saw using this instructional practice at his prior campus. Teachers are the number one influence on student achievement (Marzano, 2003), so question mapping provides a…

  12. Curiosity Questions

    ERIC Educational Resources Information Center

    Nelsen, Jane; DeLorenzo, Chip

    2010-01-01

    Have you ever found yourself lecturing a child, with the best of intentions, in an attempt to help him or her learn a lesson or process a situation in a manner that you feel will be productive? Curiosity questions, which the authors also call What and How questions, help children process an experience, event, or natural consequence so that they…

  13. Walking on Mars

    NASA Astrophysics Data System (ADS)

    Cavagna, G. A.; Willems, P. A.; Heglund, N. C.

    1998-06-01

    Sometime in the near future humans may walk in the reduced gravity of Mars. Gravity plays an essential role in walking. On Earth, the body uses gravity to `fall forwards' at each step and then the forward speed is used to restore the initial height in a pendulum-like mechanism. When gravity is reduced, as on the Moon or Mars, the mechanism of walking must change. Here we investigate the mechanics of walking on Mars onboard an aircraft undergoing gravity-reducing flight profiles. The optimal walking speed on Mars will be 3.4 km h-1 (down from 5.5 km h-1 on Earth) and the work done per unit distance to move the centre of mass will be half that on Earth.

  14. Anyonic quantum walks

    SciTech Connect

    Brennen, Gavin K.; Ellinas, Demosthenes; Kendon, Viv; Pachos, Jiannis K. Tsohantjis, Ioannis; Wang Zhenghan

    2010-03-15

    The one dimensional quantum walk of anyonic systems is presented. The anyonic walker performs braiding operations with stationary anyons of the same type ordered canonically on the line of the walk. Abelian as well as non-Abelian anyons are studied and it is shown that they have very different properties. Abelian anyonic walks demonstrate the expected quadratic quantum speedup. Non-Abelian anyonic walks are much more subtle. The exponential increase of the system's Hilbert space and the particular statistical evolution of non-Abelian anyons give a variety of new behaviors. The position distribution of the walker is related to Jones polynomials, topological invariants of the links created by the anyonic world-lines during the walk. Several examples such as the SU(2){sub k} and the quantum double models are considered that provide insight to the rich diffusion properties of anyons.

  15. Lévy walks

    NASA Astrophysics Data System (ADS)

    Zaburdaev, V.; Denisov, S.; Klafter, J.

    2015-04-01

    Random walk is a fundamental concept with applications ranging from quantum physics to econometrics. Remarkably, one specific model of random walks appears to be ubiquitous across many fields as a tool to analyze transport phenomena in which the dispersal process is faster than dictated by Brownian diffusion. The Lévy-walk model combines two key features, the ability to generate anomalously fast diffusion and a finite velocity of a random walker. Recent results in optics, Hamiltonian chaos, cold atom dynamics, biophysics, and behavioral science demonstrate that this particular type of random walk provides significant insight into complex transport phenomena. This review gives a self-consistent introduction to Lévy walks, surveys their existing applications, including latest advances, and outlines further perspectives.

  16. Maximize a Team-Based Learning Gallery Walk Experience: Herding Cats Is Easier than You Think

    ERIC Educational Resources Information Center

    Rodenbaugh, David W.

    2015-01-01

    Team-based learning (TBL) is an instructional strategy that promotes small group learning and peer instruction in a large class environment. TBL is structured to include the following steps: 1) student preparation, e.g., reading/reviewing course lectures, and 2) readiness assurance testing. Preparation and foundational knowledge is assessed on an…

  17. Innovation in Data-Driven Decision Making within SWPBIS Systems: Welcome to the Gallery Walk

    ERIC Educational Resources Information Center

    Kennedy, Michael J.; Mimmack, Jody; Flannery, K. Brigid

    2012-01-01

    Schools implementing school-wide positive behavioral interventions and supports (SWPBIS) at the high school level face the same challenges as elementary and middle schools, but also encounter an additional set of barriers all their own. To name but a few, these barriers include the need to focus on dropout prevention, postsecondary outcomes,…

  18. Quantum walks on simplicial complexes

    NASA Astrophysics Data System (ADS)

    Matsue, Kaname; Ogurisu, Osamu; Segawa, Etsuo

    2016-05-01

    We construct a new type of quantum walks on simplicial complexes as a natural extension of the well-known Szegedy walk on graphs. One can numerically observe that our proposing quantum walks possess linear spreading and localization as in the case of the Grover walk on lattices. Moreover, our numerical simulation suggests that localization of our quantum walks reflects not only topological but also geometric structures. On the other hand, our proposing quantum walk contains an intrinsic problem concerning exhibition of non-trivial behavior, which is not seen in typical quantum walks such as Grover walks on graphs.

  19. Reconfigurable Liquid Whispering Gallery Mode Microlasers

    PubMed Central

    Yang, Shancheng; Ta, Van Duong; Wang, Yue; Chen, Rui; He, Tingchao; Demir, Hilmi Volkan; Sun, Handong

    2016-01-01

    Engineering photonic devices from liquid has been emerging as a fascinating research avenue. Reconfigurably tuning liquid optical micro-devices are highly desirable but remain extremely challenging because of the fluidic nature. In this article we demonstrate an all-liquid tunable whispering gallery mode microlaser floating on a liquid surface fabricated by using inkjet print technique. We show that the cavity resonance of such liquid lasers could be reconfigurably manipulated by surface tension alteration originated from the tiny concentration change of the surfactant in the supporting liquid. As such, remarkable sensing of water-soluble organic compounds with a sensitivity of free spectral range as high as 19.85 THz / (mol · mL−1) and the detectivity limit around 5.56 × 10−3 mol · mL−1 is achieved. Our work provides not only a novel approach to effectively tuning a laser resonator but also new insight into potential applications in biological, chemical and environmental sensing. PMID:27256771

  20. Reconfigurable Liquid Whispering Gallery Mode Microlasers.

    PubMed

    Yang, Shancheng; Ta, Van Duong; Wang, Yue; Chen, Rui; He, Tingchao; Demir, Hilmi Volkan; Sun, Handong

    2016-01-01

    Engineering photonic devices from liquid has been emerging as a fascinating research avenue. Reconfigurably tuning liquid optical micro-devices are highly desirable but remain extremely challenging because of the fluidic nature. In this article we demonstrate an all-liquid tunable whispering gallery mode microlaser floating on a liquid surface fabricated by using inkjet print technique. We show that the cavity resonance of such liquid lasers could be reconfigurably manipulated by surface tension alteration originated from the tiny concentration change of the surfactant in the supporting liquid. As such, remarkable sensing of water-soluble organic compounds with a sensitivity of free spectral range as high as 19.85 THz / (mol · mL(-1)) and the detectivity limit around 5.56 × 10(-3) mol · mL(-1) is achieved. Our work provides not only a novel approach to effectively tuning a laser resonator but also new insight into potential applications in biological, chemical and environmental sensing. PMID:27256771

  1. Reconfigurable Liquid Whispering Gallery Mode Microlasers

    NASA Astrophysics Data System (ADS)

    Yang, Shancheng; Ta, Van Duong; Wang, Yue; Chen, Rui; He, Tingchao; Demir, Hilmi Volkan; Sun, Handong

    2016-06-01

    Engineering photonic devices from liquid has been emerging as a fascinating research avenue. Reconfigurably tuning liquid optical micro-devices are highly desirable but remain extremely challenging because of the fluidic nature. In this article we demonstrate an all-liquid tunable whispering gallery mode microlaser floating on a liquid surface fabricated by using inkjet print technique. We show that the cavity resonance of such liquid lasers could be reconfigurably manipulated by surface tension alteration originated from the tiny concentration change of the surfactant in the supporting liquid. As such, remarkable sensing of water-soluble organic compounds with a sensitivity of free spectral range as high as 19.85 THz / (mol · mL‑1) and the detectivity limit around 5.56 × 10‑3 mol · mL‑1 is achieved. Our work provides not only a novel approach to effectively tuning a laser resonator but also new insight into potential applications in biological, chemical and environmental sensing.

  2. Fermi questions

    NASA Astrophysics Data System (ADS)

    Bouffard, Karen

    1999-05-01

    This column contains problems and solutions for the general category of questions known as "Fermi" questions. Forcing the students to use their ability to estimate, giving answers in terms of order-of-magnitude, is not only a challenge for a competition, but a teaching strategy to use in the classroom to develop self-confidence and the ability to analyze answers as to whether or not they make sense, as opposed to relying on the "precision" of a calculator value.

  3. Beyond the Gallery Forest: Contrasting Habitat and Diet in Lemur catta Troops at Bezà Mahafaly Special Reserve.

    PubMed

    Yamashita, Nayuta; Sauther, Michelle L; Cuozzo, Frank P; Youssouf Jacky, Ibrahim Antho

    2015-01-01

    Ring-tailed lemurs have been studied intensively in the Parcel 1 gallery forest of Bezà Mahafaly Special Reserve. Here, we report on lemur groups in a mixture of deciduous dry forest and spiny forest just 5 km to the west. Compared to Parcel 1, Parcel 2 (P2) has a lower density of Tamarindus indica, a major dietary plant species for gallery forest lemurs. Recent studies in drier habitats have called into question the association of lemur density and tamarind presence. In order to address this question, we measured forest structure and composition of plant plots between parcels and conducted lemur feeding observations. The trees and shrubs within the parcels did not differ in height or diameter at breast height, but the frequencies of plant species that were common between parcels were significantly different. Numbers of feeding observations on foods common to both parcels did not differ, but their relative rankings within parcels did. Frequencies of food plants corresponded to earlier reports of lemur population densities. However, we found that the ring-tailed lemur diet is a mixture of plants that are eaten in abundance regardless of frequency and those that are locally available. In terms of their reliance on Tamarindus, P2 animals appear intermediate between those in gallery forests and nontamarind sites. PMID:26022299

  4. Whispering-Gallery-Mode Tunable Narrow-Band-Pass Filter

    NASA Technical Reports Server (NTRS)

    Savchenkov, Anatoliy; Iltchenko, Vladimir; Matsko, Andrey; Maleki, Lute

    2004-01-01

    An experimental tunable, narrow-band-pass electro-optical filter is based on a whispering-gallery resonator. This device is a prototype of tunable filters needed for the further development of reconfigurable networking wavelength-division multiplexers and communication systems that utilize radio-frequency (more specifically, microwave) subcarrier signals on optical carrier signals. The characteristics of whispering-gallery resonators that make them attractive for such applications include high tuning speed, compactness, wide tuning range, low power consumption, and compatibility with single-mode optical fibers. In addition, relative to Fabry-Perot resonators, these devices offer advantages of greater robustness and lower cost. As described in several prior NASA Tech Briefs articles, a whispering-gallery resonator is a spheroidal, disk-like, or toroidal body made of a highly transparent material. It is so named because it is designed to exploit whispering-gallery electromagnetic modes, which are waveguide modes that propagate circumferentially and are concentrated in a narrow toroidal region centered on the equatorial plane and located near the outermost edge. The experimental whispering-gallery tunable filter (see figure) is made from a disk of Z-cut LiNbO3 of 4.8-mm diameter and 0.17-mm thickness. The perimeter of the disk is rounded to a radius of curvature of 100 m. Metal coats on the flat faces of the disk serve as electrodes for exploiting the electro-optical effect in LiNbO3 for tuning. There is no metal coat on the rounded perimeter region, where the whispering-gallery modes propagate. Light is coupled from an input optical fiber into the whispering-gallery modes by means of a diamond prism. Another diamond prism is used to couple light from the whispering-gallery modes to an output optical fiber. This device is designed and operated to exploit transverse magnetic (TM) whispering- gallery modes, rather than transverse electric (TE) modes because the

  5. CyberSpace: Adler's Computer-Based Gallery

    NASA Astrophysics Data System (ADS)

    Salgado, J.

    2002-05-01

    The Adler Planetarium & Astronomy Museum has recently opened its CyberSpace Gallery. This gallery is a radical departure from a typical museum exhibit space. It fuses all the potential that computer technology enables into one programmable museum gallery. In this entirely computer-based facility, content is flexibly updated and routed to various display/interactive stations in its three different spaces: the informal gallery, the classroom, and the distance learning studio. These spaces can be configured into individualized and theme-based exhibits, classrooms, and videoconferencing centers to host events that can be transmitted and/or received via high bandwidth internet connectivity. CyberSpace relies on more than seventy computers to drive all exhibit components, which includes 16 plasma displays, 16 computer stations, 4 immersive workstations, and 10 video projectors. All these components are used to present externally produced material as well as in-house content produced by professional staff astronomers and educators. In addition to its ``everyday" use as a multimedia gallery for museum visitors, CyberSpace has been used for teacher professional development, school field trip experiences, live demonstrations, presentations of NASA events, including launches and ISS-shuttle missions, and public astronomy classes.

  6. Kinematic evaluation of virtual walking trajectories.

    PubMed

    Cirio, Gabriel; Olivier, Anne-Hélène; Marchal, Maud; Pettré, Julien

    2013-04-01

    Virtual walking, a fundamental task in Virtual Reality (VR), is greatly influenced by the locomotion interface being used, by the specificities of input and output devices, and by the way the virtual environment is represented. No matter how virtual walking is controlled, the generation of realistic virtual trajectories is absolutely required for some applications, especially those dedicated to the study of walking behaviors in VR, navigation through virtual places for architecture, rehabilitation and training. Previous studies focused on evaluating the realism of locomotion trajectories have mostly considered the result of the locomotion task (efficiency, accuracy) and its subjective perception (presence, cybersickness). Few focused on the locomotion trajectory itself, but in situation of geometrically constrained task. In this paper, we study the realism of unconstrained trajectories produced during virtual walking by addressing the following question: did the user reach his destination by virtually walking along a trajectory he would have followed in similar real conditions? To this end, we propose a comprehensive evaluation framework consisting on a set of trajectographical criteria and a locomotion model to generate reference trajectories. We consider a simple locomotion task where users walk between two oriented points in space. The travel path is analyzed both geometrically and temporally in comparison to simulated reference trajectories. In addition, we demonstrate the framework over a user study which considered an initial set of common and frequent virtual walking conditions, namely different input devices, output display devices, control laws, and visualization modalities. The study provides insight into the relative contributions of each condition to the overall realism of the resulting virtual trajectories. PMID:23428452

  7. Walking: technology and biology.

    PubMed

    Pfeiffer, Friedrich; Inoue, Hirochika

    2007-01-15

    If all the signs are to be believed, then the twenty-first century will technologically be characterized by machine walking and its relevant products, which possess all chances to become real bulk goods in the course of the next decades. With several university institutes and with Honda and Sony from the industrial side, Japan is today and without any doubt the leading nation in research and development of walking machines. The US and Europe follow at some distance. Walking machines will influence all areas of daily and industrial life and, with the fast evolution of artificial intelligence, will become a real partner of human beings. All relevant technologies are highly interdisciplinary, they will push the future technologies of all technical fields. The special issue on this topic gives a selection of walking machine research and development including some aspects from biology. PMID:17148046

  8. Early Walking of Geriatric Amputees

    PubMed Central

    Devas, M. B.

    1971-01-01

    After amputation geriatric patients have been enabled to get up and walk with the help of a prosthesis, an “early walking aid.” The physiotherapist measures the patient, fits the early walking aid, and instructs him in walking. The prosthesis is simple to make, easy to apply, and allows early walking with the use of a walking frame or sticks. Thus the geriatric amputee can walk as soon after operation as his general condition allows and the surgeon wishes. ImagesFIG. 1FIG. 2 PMID:5100378

  9. HIV seropositivity of needles from shooting galleries in south Florida.

    PubMed

    Chitwood, D D; McCoy, C B; Inciardi, J A; McBride, D C; Comerford, M; Trapido, E; McCoy, H V; Page, J B; Griffin, J; Fletcher, M A

    1990-02-01

    Needle/syringe combinations were collected from three shooting galleries in South Florida and tested for the presence of antibodies to HIV-1. Fifteen of 148 needles (10.1 percent) tested positive for HIV-1 antibody. Seropositivity rates did not vary by the day of the week of collection, nor by shooting gallery from which they were collected. When the needle appeared to contain blood residue, 20.0 percent were positive versus 5.1 percent with no blood residue. These findings suggest that needles/syringes used in shooting galleries are likely to serve as reservoirs and/or vectors of transmission of the HIV-1 virus, and that although visual inspection of the needle/syringe may be useful in lessening the chance for transmission, even the visually "clean" needles may result in transmission of infection. PMID:2297056

  10. Indoor/outdoor ozone concentrations at a contemporary art gallery

    SciTech Connect

    Davies, T.D.; Ramer, B.; Kaspyzok, G.; Delany, A.C.

    1984-02-01

    Ozone concentrations were measured both inside and outside the Sainsbury Centre for Visual Arts, near a small city in rural eastern England, during a three-week period in summer. The inside concentration was typically 70 +/- 10% of the outside concentration during the period of expected maximum outside levels. During the period of observation the maximum outside ozone levels have been well in excess of 120 ppb. The relatively high indoor/outdoor ozone ratio is a function of the Centre's design, its internal geometry, and its ventilation system. Conventional art galleries and museums experience much lower indoor ozone exposure. The measured indoor ozone levels imply deleterious effects on the gallery exhibits and an enhanced ozone exposure may have to be considered in the design of modern galleries and museums. 8 references.

  11. Ringing phenomenon based whispering-gallery-mode sensing

    PubMed Central

    Ye, Ming-Yong; Shen, Mei-Xia; Lin, Xiu-Min

    2016-01-01

    Highly sensitive sensing is one of the most important applications of whispering-gallery-mode (WGM) microresonators, which is usually accomplished through a tunable continuous-wave laser sweeping over a whispering-gallery mode with the help of a fiber taper in a relative slow speed. It is known that if a tunable continuous-wave laser sweeps over a high quality whispering-gallery mode in a fast speed, a ringing phenomenon will be observed. The ringing phenomenon in WGM microresonators is mainly used to measure the Q factors and mode-coupling strengths. Here we experimentally demonstrate that the WGM sensing can be achieved based on the ringing phenomenon. This kind of sensing is accomplished in a much shorter time and is immune to the noise caused by the laser wavelength drift. PMID:26796871

  12. Four Questions

    ERIC Educational Resources Information Center

    Hark-Weber, Amara G., Ed.

    2013-01-01

    Teaching artists often find themselves working in schools and communities that are new to them, whether these are situations close to home or farther afield. This issue of Four Questions highlights teaching artists who travel extensively as part of their teaching and artistic practices and bring their expertise, energy, and creativity to…

  13. Questionable Exercises.

    ERIC Educational Resources Information Center

    Liemohn, Wendell; Haydu, Traci; Phillips, Dawn

    1999-01-01

    This publication presents general guidelines for exercise prescription that have an anatomical basis but also consider the exerciser's ability to do the exercise correctly. It reviews various common questionable exercises, explaining how some exercises, especially those designed for flexibility and muscle fitness, can cause harm. Safer…

  14. [Comparison of kinematic and kinetic parameters between the locomotion patterns in nordic walking, walking and running].

    PubMed

    Kleindienst, F I; Michel, K J; Schwarz, J; Krabbe, B

    2006-03-01

    Based on a higher cardio-pulmonary and cardio-vascular benefit and a promised reduction of mechanical load of the musculoskeletal system Nordic Walking (NW) shows an increased market potential. The present study should investigate whether there are biomechanical differences between the locomotion patterns NW, walking and running. Moreover possible resultant load differences should be determined. Eleven subjects, who were already experienced with the NW-technique, participated in this experiment. The kinematic data were collected using two high-speed camera systems from posterior and from lateral at the same time. Simultaneously the ground reaction forces were recorded. The kinematic and the kinetic data reveal differences between the three analyzed locomotion patterns. For NW as well as walking the mechanical load of the lower extremity is lower compared to running. None of the kinematic parameters suggest a "physiological benefit" of NW compared to walking. Moreover NW shows higher vertical and horizontal forces during landing. Exclusively the lower vertical force peak during push off indicates a lower mechanical load for NW in comparison to walking. Consequently it is questionable is NW -- based on its promised "biomechanical benefits" compared to walking -- should be still recommended for overweight people and for people with existing musculoskeletal problems of the lower limb. PMID:16544213

  15. Whispering Gallery Mode Spectroscopy as a Diagnostic for Dusty Plasmas

    SciTech Connect

    Thieme, G.; Basner, R.; Ehlbeck, J.; Roepcke, J.; Maurer, H.; Kersten, H.; Davies, P. B.

    2008-09-07

    Whispering-gallery-mode spectroscopy is being assessed as a diagnostic method for the characterisation of size and chemical composition of spherical particles levitated in a plasma. With a pulsed laser whispering gallery modes (cavity resonances) are excited in individual microspheres leading to enhanced Raman scattering or fluorescence at characteristic wavelengths. This method can be used to gain specific information from the particle surface and is thus of great interest for the characterisation of layers deposited on microparticles, e.g. in molecular plasmas. We present investigations of different microparticles in air and results from fluorescent particles levitated in an Argon rf plasma.

  16. Theory of anisotropic whispering-gallery-mode resonators

    SciTech Connect

    Ornigotti, Marco

    2011-07-15

    An analytic solution for a uniaxial spherical resonator is presented using the method of Debye potentials. This serves as a starting point for the calculation of whispering gallery modes (WGMs) in such a resonator. Suitable approximations for the radial functions are discussed in order to best characterize WGMs. The characteristic equation and its asymptotic expansion for the anisotropic case is also discussed, and an analytic formula with a precision of the order O[{nu}{sup -1}] is also given. Our careful treatment of both boundary conditions and asymptotic expansions makes the present work a particularly suitable platform for a quantum theory of whispering gallery resonators.

  17. Portion of Enhanced 360-degree Gallery Pan

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This is a sub-section of the 'geometrically improved, color enhanced' version of the 360-degree panorama heretofore known as the 'Gallery Pan', the first contiguous, uniform panorama taken by the Imager for Mars Pathfinder (IMP) over the course of Sols 8, 9, and 10. Different regions were imaged at different times over the three Martian days to acquire consistent lighting and shadow conditions for all areas of the panorama.

    The IMP is a stereo imaging system that, in its fully deployed configuration, stands 1.8 meters above the Martian surface, and has a resolution of two millimeters at a range of two meters. In this geometrically improved version of the panorama, distortion due to a 2.5 degree tilt in the IMP camera mast has been removed, effectively flattening the horizon.

    The IMP has color capability provided by 24 selectable filters -- twelve filters per 'eye'. Its red, green, and blue filters were used to take this image. The color was digitally balanced according to the color transmittance capability of a high-resolution TV at the Jet Propulsion Laboratory (JPL), and is dependent on that device. In this color enhanced version of the panorama, detail in surface features are brought out via changes to saturation and intensity, holding the original hue constant. A threshold was applied to avoid changes to the sky.

    At left is a Lander petal and a metallic mast which is a portion of the low-gain antenna. Misregistration in the antenna and other Lander features is due to parallax in the extreme foreground. Another Lander petal is at the right, showing the fully deployed forward ramp.

    Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is a division of the California Institute of Technology (Caltech). The IMP was developed by the University

  18. D.U.C.K. Walking.

    ERIC Educational Resources Information Center

    Steller, Jenifer J.

    This manual presents a schoolwide walking program that includes aerobic fitness information, curriculum integration, and walking tours. "Discover and Understand Carolina Kids by Walking" is D.U.C.K. Walking. An aerobic walking activity, D.U.C.K. Walking has two major goals: (1) to promote regular walking as a way to exercise at any age; and (2) to…

  19. Labyrinth walking in corrections.

    PubMed

    Zucker, Donna M; Sharma, Amy

    2012-02-01

    A 6 week labyrinth walking program was pilot tested in a correctional setting and goals were to: 1) determine the feasibility of a labyrinth walking curriculum; 2) pilot test measures of health related quality of life (QOL) (pre and post-surveys) and blood pressure; and 3) examine the influence of relationship-centered teaching on subject satisfaction. Relational communication was used as a framework for this study, emphasizing concepts of trust, competency and similarly in the teacher. A pretest/posttest descriptive design was used. The sample was 14 offenders at a Massachusetts county jail. The intervention included six 90 minute sessions, composed of a lecture, a labyrinth walk, and journal writing. Measures included a demographic survey; pre and post session walk blood pressures; pre and post program QOL measures; and a post program measure of satisfaction. The sample was 57% Caucasian, 36% Hispanic, and 7% African American, with an average age of 34, mostly high school educated and single. Drug of choice was alcohol with age of use at 12 and 1/2 years. Seventy-nine percent were previously incarcerated more than twice. QOL data were not changed pre to post. BP data trended in a healthy direction from weeks 1 to 6. Satisfaction with the teacher and the program was high. The labyrinth walking pilot program was proven feasible, low cost and satisfying for the participants. Recommendations for future studies are discussed. PMID:22468660

  20. Walks on SPR neighborhoods.

    PubMed

    Caceres, Alan Joseph J; Castillo, Juan; Lee, Jinnie; St John, Katherine

    2013-01-01

    A nearest-neighbor-interchange (NNI)-walk is a sequence of unrooted phylogenetic trees, T1, T2, . . . , T(k) where each consecutive pair of trees differs by a single NNI move. We give tight bounds on the length of the shortest NNI-walks that visit all trees in a subtree-prune-and-regraft (SPR) neighborhood of a given tree. For any unrooted, binary tree, T, on n leaves, the shortest walk takes Θ(n²) additional steps more than the number of trees in the SPR neighborhood. This answers Bryant’s Second Combinatorial Challenge from the Phylogenetics Challenges List, the Isaac Newton Institute, 2011, and the Penny Ante Problem List, 2009. PMID:23702562

  1. At 1050 Gallery, Block 65, view of coaster gate bypass ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    At 1050 Gallery, Block 65, view of coaster gate bypass valve (for turbine-generator unit G-10, this bypass-valve unit manufactured by Western Koppers Co., Fort Wayne, Ind., 1938), looking southeast. - Columbia Basin Project, Grand Coulee Dam & Franklin D. Roosevelt Lake, Across Columbia River, Southeast of Town of Grand Coulee, Grand Coulee, Grant County, WA

  2. At 1050 Gallery, Block 16, view of access port down ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    At 1050 Gallery, Block 16, view of access port down to top of penstock (this is a service hatch into penstock for turbine-generator unit No. 2), looking north. - Columbia Basin Project, Grand Coulee Dam & Franklin D. Roosevelt Lake, Across Columbia River, Southeast of Town of Grand Coulee, Grand Coulee, Grant County, WA

  3. At 1050 Gallery, Block 55, view of gate control and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    At 1050 Gallery, Block 55, view of gate control and motor, looking west, (Westinghouse Gearmotor, ca. 1939, type CS induction motor, 440 volts, 43 rpm, 60 cycle). - Columbia Basin Project, Grand Coulee Dam & Franklin D. Roosevelt Lake, Across Columbia River, Southeast of Town of Grand Coulee, Grand Coulee, Grant County, WA

  4. 71. (Credit JTL) Pipe gallery looking south in basement underneath ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    71. (Credit JTL) Pipe gallery looking south in basement underneath 1910-11 and 1924 filter wing extensions. Note bottoms of converted New York horizontal pressure filters in right background. - McNeil Street Pumping Station, McNeil Street & Cross Bayou, Shreveport, Caddo Parish, LA

  5. 8. MAIN INLET FROM FILTER GALLERY AND CANAL INTO HINDS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. MAIN INLET FROM FILTER GALLERY AND CANAL INTO HINDS PLANT. VIEW LOOKING DUE WEST OF HINDS COMPLEX IN BACKGROUND OF SAND FILTERS. - Hinds Pump Plant, East of Joshua Tree National Monument, 5 miles north of Route 10, Hayfield, Riverside County, CA

  6. Optical filter having coupled whispering-gallery-mode resonators

    NASA Technical Reports Server (NTRS)

    Savchenkov, Anatoliy (Inventor); Ilchenko, Vladimir (Inventor); Maleki, Lutfollah (Inventor); Handley, Timothy A. (Inventor)

    2006-01-01

    Optical filters having at least two coupled whispering-gallery-mode (WGM) optical resonators to produce a second order or higher order filter function with a desired spectral profile. At least one of the coupled WGM optical resonators may be tunable by a control signal to adjust the filtering function.

  7. 40. CONSTRUCTION OF GALLERY NO. 3, SHOWING INCLINED PLANE USED ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    40. CONSTRUCTION OF GALLERY NO. 3, SHOWING INCLINED PLANE USED TO TRANSPORT MATERIALS, ALSO SPOIL FROM TUNNEL INTERIOR. POWDER HOUSE AND TOOL SHED VISIBLE TO RIGHT OF BASE INCLINE - Zion-Mount Carmel Highway, Tunnel, Two miles east of Zion Canyon Scenic Drive, Springdale, Washington County, UT

  8. 20. Photocopy of photo engraving (from August Spies' Spies' Gallery ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    20. Photocopy of photo engraving (from August Spies' Spies' Gallery of Photo Engravings, Soldiers' and Sailors' Home, Sandusky, Ohio, (August Spies), 1902) SECOND FLOOR, GRAND ARMY HALL, LOOKING SOUTH - Ohio Soldiers' & Sailors' Home, Library, U.S. Route 250 at DeWitt Avenue, Sandusky, Erie County, OH

  9. 18. Photocopy of photo engraving (from August Spies' Spies' Gallery ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    18. Photocopy of photo engraving (from August Spies' Spies' Gallery of Photo Engravings, Soldiers' and Sailors' Home, Sandusky, Ohio, (August Spies), 1902) FIRST FLOOR, READING ROOM, LOOKING WEST (INSET NORTHEAST FRONT) - Ohio Soldiers' & Sailors' Home, Library, U.S. Route 250 at DeWitt Avenue, Sandusky, Erie County, OH

  10. 13. Photocopy of photo engraving (from August Spies' Spies' Gallery ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. Photocopy of photo engraving (from August Spies' Spies' Gallery of Photo Engravings, Soldiers' and Sailors' Home, Sandusky, Ohio, (August Spies), 1902) VIEW SOUTHEAST, NORTHWEST FRONT - Ohio Soldiers' & Sailors' Home, Cottage M, U.S. Route 250 at DeWitt Avenue, Sandusky, Erie County, OH

  11. 45. MAIN MEETING ROOM COLUMNS. Ends of gallery columns identified ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    45. MAIN MEETING ROOM COLUMNS. Ends of gallery columns identified at the time of removal for transfer to the George School for re-erection. The stamp reads, 'REMOVED FROM 12th ST. MTG HSE PHILA 1972'. - Twelfth Street Meeting House, 20 South Twelfth Street, Philadelphia, Philadelphia County, PA

  12. 13. VIEW OF EAST OPERATING GALLERY ALONG THE POSTMORTEM CELLS. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. VIEW OF EAST OPERATING GALLERY ALONG THE POST-MORTEM CELLS. A NUMBER OF MANIPULATOR ARMS COVERED WITH PLASTIC ARE ON THE LEFT WALL. - Nevada Test Site, Engine Maintenance Assembly & Disassembly Facility, Area 25, Jackass Flats, Mercury, Nye County, NV

  13. At 1295 Gallery, Block 31, view of truck for hauling ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    At 1295 Gallery, Block 31, view of truck for hauling coaster gates; note track at perpendicular; the elevator at Block 31 is to the left. - Columbia Basin Project, Grand Coulee Dam & Franklin D. Roosevelt Lake, Across Columbia River, Southeast of Town of Grand Coulee, Grand Coulee, Grant County, WA

  14. At 1200 Gallery, Block 63, looking west, showing 230 kv ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    At 1200 Gallery, Block 63, looking west, showing 230 kv cables. These lines were installed in the 1960s and are no longer used. - Columbia Basin Project, Grand Coulee Dam & Franklin D. Roosevelt Lake, Across Columbia River, Southeast of Town of Grand Coulee, Grand Coulee, Grant County, WA

  15. At 1200 Gallery, Block 63, looking down tunnel that extends ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    At 1200 Gallery, Block 63, looking down tunnel that extends to the Right Powerhouse, showing 230 kva lines. - Columbia Basin Project, Grand Coulee Dam & Franklin D. Roosevelt Lake, Across Columbia River, Southeast of Town of Grand Coulee, Grand Coulee, Grant County, WA

  16. Whisper gallery mirrors reflectivities from 100 [angstrom] to 500 [angstrom

    SciTech Connect

    Hung, Tsen-Yu; Hagelstein, P.L.

    1990-01-01

    We have examined optical constants and predicted reflectivities of candidate surface coatings for whisper gallery mirrors in the extreme ultraviolet (100 [Angstrom] to 500 [Angstrom]). Previous work of Vinogradov and coworkers have identified the spectral regime near 100-150 [Angstrom] as particularly promising due to the high whisper gallery mirror reflectivities of the noble metals in the vicinity of their Cooper minima in this regime. We confirm this basic result using newer optical data, and we have sought surface materials which would extend the range over which the whisper gallery mirrors may be used: between 100 to 500 [Angstrom]. We find that substantial whisper gallery mirror reflectivities (near or greater than 50%) are predicted for a variety of elements, and that the TE peak reflection is larger than TM peak reflection by on the order of 10%. However, most of the elements which do reflect well have surfaces that are vulnerable to oxygen contamination, which seriously degrades mirror performance. A cryogenic mirror design using a dynamic solid rare gas surface which has the potential to defeat such surface contaminations is described: it has peak reflectivity of more than 50% centered near 280 [Angstrom]. 8 figs, 18 refs.

  17. Whisper gallery mirrors reflectivities from 100 {angstrom} to 500 {angstrom}

    SciTech Connect

    Hung, Tsen-Yu; Hagelstein, P.L.

    1990-12-31

    We have examined optical constants and predicted reflectivities of candidate surface coatings for whisper gallery mirrors in the extreme ultraviolet (100 {Angstrom} to 500 {Angstrom}). Previous work of Vinogradov and coworkers have identified the spectral regime near 100-150 {Angstrom} as particularly promising due to the high whisper gallery mirror reflectivities of the noble metals in the vicinity of their Cooper minima in this regime. We confirm this basic result using newer optical data, and we have sought surface materials which would extend the range over which the whisper gallery mirrors may be used: between 100 to 500 {Angstrom}. We find that substantial whisper gallery mirror reflectivities (near or greater than 50%) are predicted for a variety of elements, and that the TE peak reflection is larger than TM peak reflection by on the order of 10%. However, most of the elements which do reflect well have surfaces that are vulnerable to oxygen contamination, which seriously degrades mirror performance. A cryogenic mirror design using a dynamic solid rare gas surface which has the potential to defeat such surface contaminations is described: it has peak reflectivity of more than 50% centered near 280 {Angstrom}. 8 figs, 18 refs.

  18. 11. VIEW, LOOKING SOUTHEAST, OF GALLERY D UNDER ERECTION March ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. VIEW, LOOKING SOUTHEAST, OF GALLERY D UNDER ERECTION March 20, 1922 (Original negative destroyed; print in Barge Canal Construction Photographs, Box 12, Series 501, Accession No. 336-85) - New York Barge Canal, Gowanus Bay Terminal Pier, East of bulkhead supporting Columbia Street, Brooklyn, Kings County, NY

  19. 12. VIEW, LOOKING SOUTHEAST, OF GALLERIES C AND D, July ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. VIEW, LOOKING SOUTHEAST, OF GALLERIES C AND D, July 17, 1922 (Original negative destroyed; print in Barge Canal Construction Photographs, Box 12, Series 501, Accession No. 336-85) - New York Barge Canal, Gowanus Bay Terminal Pier, East of bulkhead supporting Columbia Street, Brooklyn, Kings County, NY

  20. Nonlinear mode coupling in whispering-gallery-mode resonators

    NASA Astrophysics Data System (ADS)

    D'Aguanno, Giuseppe; Menyuk, Curtis R.

    2016-04-01

    We present a first-principles derivation of the coupled nonlinear Schrödinger equations that govern the interaction between two families of modes with different transverse profiles in a generic whispering-gallery-mode resonator. We find regions of modulational instability and the existence of trains of bright solitons in both the normal and the anomalous dispersion regime.

  1. 42. VALVEHOUSE FOR NEEDLE VALVE OUTLET WORKS ON GALLERY 2, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    42. VALVEHOUSE FOR NEEDLE VALVE OUTLET WORKS ON GALLERY 2, SHOWING OVERHEAD SERVICE CRANE AT CENTER. NOTE NEEDLE VALVE AIR VENTS AND GAUGES AT RIGHT, NEXT TO CONTROL PEDESTAL. VIEW TO EAST. - Owyhee Dam, Across Owyhee River, Nyssa, Malheur County, OR

  2. From GUI to Gallery: A Study of Online Virtual Environments.

    ERIC Educational Resources Information Center

    Guynup, Stephen Lawrence

    This paper began as an attempt to clarify and classify the development of Web3D environments from 1995 to the present. In that process, important facts came to light. A large proportion of these sites were virtual galleries and museums. Second, these same environments covered a wide array of architectural interpretations and represented some of…

  3. LONG GALLERY; NORTH WALL, MIDDLE RIGHT. Glass plate stereopair number ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    LONG GALLERY; NORTH WALL, MIDDLE RIGHT. Glass plate stereopair number PA-1430-139 LC-HABS-GS05-LG-N-9 157.4870. Right (not printed) - Independence Hall Complex, Independence Hall, 500 Chestnut Street, Philadelphia, Philadelphia County, PA

  4. 4. LOOKING WEST FROM THE VISITORS' GALLERY ABOVE THE SOUTH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. LOOKING WEST FROM THE VISITORS' GALLERY ABOVE THE SOUTH END OF LEVEL 4; SAWTOOTH MONITORS PROVIDED AMPLE NATURAL LIGHT FOR KILLING OPERATIONS; STEEL SUBSTRUCTURE NEAR BOTTOM OF PHOTO SUPPORTED CHAIN CONVEYOR SYSTEM - Rath Packing Company, Beef Killing Building, Sycamore Street between Elm & Eighteenth Streets, Waterloo, Black Hawk County, IA

  5. 5. INTERIOR VIEW OF LAUNDRY ROOM ON GALLERY LEVEL, NEAR ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. INTERIOR VIEW OF LAUNDRY ROOM ON GALLERY LEVEL, NEAR SOUTHWEST CORNER OF BUILDING 149; WORKERS' UNIFORMS AND BEEF SHROUDS WERE LAUNDERED HERE; CLEAN BEEF SHROUDS WERE RETURNED TO DISASSEMBLY LINE ON LEVEL 4 THROUGH FUNNEL-SHAPED CHUTE AT LOWER LEFT - Rath Packing Company, Beef Killing Building, Sycamore Street between Elm & Eighteenth Streets, Waterloo, Black Hawk County, IA

  6. Cross-Curricular Gallery Learning: A Phenomenological Case Study

    ERIC Educational Resources Information Center

    Hickman, Richard; Kiss, Lauren

    2010-01-01

    This article examines the strategies that can be used to enhance students' understanding of how subjects link together and whether cross-curricular approaches, through a gallery project, have any real impact on students' understanding of the links between subjects. A substantial part of this article, however, describes the methodological aspect of…

  7. Random walks on networks

    NASA Astrophysics Data System (ADS)

    Donnelly, Isaac

    Random walks on lattices are a well used model for diffusion on continuum. They have been to model subdiffusive systems, systems with forcing and reactions as well as a combination of the three. We extend the traditional random walk framework to the network to obtain novel results. As an example due to the small graph diameter, the early time behaviour of subdiffusive dynamics dominates the observed system which has implications for models of the brain or airline networks. I would like to thank the Australian American Fulbright Association.

  8. Walking: the Cheap, Easy Workout

    MedlinePlus

    ... news/fullstory_159582.html Walking: The Cheap, Easy Workout And it's a good way to start exercising, ... endurance. You can give your upper body a workout while walking by carrying one to five pound ...

  9. Walking with a Slower Friend

    ERIC Educational Resources Information Center

    Bailey, Herb; Kalman, Dan

    2011-01-01

    Fay and Sam go for a walk. Sam walks along the left side of the street while Fay, who walks faster, starts with Sam but walks to a point on the right side of the street and then returns to meet Sam to complete one segment of their journey. We determine Fay's optimal path minimizing segment length, and thus maximizing the number of times they meet…

  10. Walking in My Shoes

    ERIC Educational Resources Information Center

    Salia, Hannah

    2010-01-01

    The Walking in My Shoes curriculum at St. Thomas School in Medina, Washington, has been developed to deepen students' understanding of their own heritage and the cultural similarities and differences among their global peers. Exploring the rich diversity of the world's cultural heritage and the interactions of global migrations throughout history,…

  11. Tips for Leading Walks.

    ERIC Educational Resources Information Center

    Kriesberg, Daniel

    2001-01-01

    Offers reminders and tips for improving interpretive walks, including having a theme, drawing on basic teaching methods, drawing on all senses rather than just talking, being a role model to show how learning can be fun, using picture books, using tools of the trade to encourage visitors to learn for themselves, and playing games. (PVD)

  12. The walking robot project

    NASA Technical Reports Server (NTRS)

    Williams, P.; Sagraniching, E.; Bennett, M.; Singh, R.

    1991-01-01

    A walking robot was designed, analyzed, and tested as an intelligent, mobile, and a terrain adaptive system. The robot's design was an application of existing technologies. The design of the six legs modified and combines well understood mechanisms and was optimized for performance, flexibility, and simplicity. The body design incorporated two tripods for walking stability and ease of turning. The electrical hardware design used modularity and distributed processing to drive the motors. The software design used feedback to coordinate the system and simple keystrokes to give commands. The walking machine can be easily adapted to hostile environments such as high radiation zones and alien terrain. The primary goal of the leg design was to create a leg capable of supporting a robot's body and electrical hardware while walking or performing desired tasks, namely those required for planetary exploration. The leg designers intent was to study the maximum amount of flexibility and maneuverability achievable by the simplest and lightest leg design. The main constraints for the leg design were leg kinematics, ease of assembly, degrees of freedom, number of motors, overall size, and weight.

  13. Take a Planet Walk

    ERIC Educational Resources Information Center

    Schuster, Dwight

    2008-01-01

    Physical models in the classroom "cannot be expected to represent the full-scale phenomenon with complete accuracy, not even in the limited set of characteristics being studied" (AAAS 1990). Therefore, by modifying a popular classroom activity called a "planet walk," teachers can explore upper elementary students' current understandings; create an…

  14. Walking Out Graphs

    ERIC Educational Resources Information Center

    Shen, Ji

    2009-01-01

    In the Walking Out Graphs Lesson described here, students experience several types of representations used to describe motion, including words, sentences, equations, graphs, data tables, and actions. The most important theme of this lesson is that students have to understand the consistency among these representations and form the habit of…

  15. Walking On Air

    NASA Video Gallery

    This video features a series of time lapse sequences photographed by the Expedition 30 crew aboard the International Space Station. Set to the song “Walking in the Air,” by Howard Blake, the v...

  16. A Walk through Time.

    ERIC Educational Resources Information Center

    Renfroe, Mark; Letendre, Wanda

    1996-01-01

    Describes a seventh-grade class project where students constructed a "time tunnel" (a walk-through display with models and exhibits illustrating various themes and eras). Beginning modestly, the tunnel grew over seven years to include 11 different display scenes. Discusses the construction of the project and benefits to the school. (MJP)

  17. Random Walks on Random Graphs

    NASA Astrophysics Data System (ADS)

    Cooper, Colin; Frieze, Alan

    The aim of this article is to discuss some of the notions and applications of random walks on finite graphs, especially as they apply to random graphs. In this section we give some basic definitions, in Section 2 we review applications of random walks in computer science, and in Section 3 we focus on walks in random graphs.

  18. [Walking abnormalities in children].

    PubMed

    Segawa, Masaya

    2010-11-01

    Walking is a spontaneous movement termed locomotion that is promoted by activation of antigravity muscles by serotonergic (5HT) neurons. Development of antigravity activity follows 3 developmental epochs of the sleep-wake (S-W) cycle and is modulated by particular 5HT neurons in each epoch. Activation of antigravity activities occurs in the first epoch (around the age of 3 to 4 months) as restriction of atonia in rapid eye movement (REM) stage and development of circadian S-W cycle. These activities strengthen in the second epoch, with modulation of day-time sleep and induction of crawling around the age of 8 months and induction of walking by 1 year. Around the age of 1 year 6 months, absence of guarded walking and interlimb cordination is observed along with modulation of day-time sleep to once in the afternoon. Bipedal walking in upright position occurs in the third epoch, with development of a biphasic S-W cycle by the age of 4-5 years. Patients with infantile autism (IA), Rett syndrome (RTT), or Tourette syndrome (TS) show failure in the development of the first, second, or third epoch, respectively. Patients with IA fail to develop interlimb coordination; those with RTT, crawling and walking; and those with TS, walking in upright posture. Basic pathophysiology underlying these condition is failure in restricting atonia in REM stage; this induces dysfunction of the pedunculopontine nucleus and consequently dys- or hypofunction of the dopamine (DA) neurons. DA hypofunction in the developing brain, associated with compensatory upward regulation of the DA receptors causes psychobehavioral disorders in infancy (IA), failure in synaptogenesis in the frontal cortex and functional development of the motor and associate cortexes in late infancy through the basal ganglia (RTT), and failure in functional development of the prefrontal cortex through the basal ganglia (TS). Further, locomotion failure in early childhood causes failure in development of functional

  19. Behavior Change Techniques Used to Promote Walking and Cycling

    PubMed Central

    Bird, Emma L.; Baker, Graham; Mutrie, Nanette; Ogilvie, David; Sahlqvist, Shannon; Powell, Jane

    2013-01-01

    Objective: Evidence on the effectiveness of walking and cycling interventions is mixed. This may be partly attributable to differences in intervention content, such as the cognitive and behavioral techniques (BCTs) used. Adopting a taxonomy of BCTs, this systematic review addressed two questions: (a) What are the behavior change techniques used in walking and cycling interventions targeted at adults? (b) What characterizes interventions that appear to be associated with changes in walking and cycling in adults? Method: Previous systematic reviews and updated database searches were used to identify controlled studies of individual-level walking and cycling interventions involving adults. Characteristics of intervention design, context, and methods were extracted in addition to outcomes. Intervention content was independently coded according to a 26-item taxonomy of BCTs. Results: Studies of 46 interventions met the inclusion criteria. Twenty-one reported a statistically significant effect on walking and cycling outcomes. Analysis revealed substantial heterogeneity in the vocabulary used to describe intervention content and the number of BCTs coded. “Prompt self-monitoring of behavior” and “prompt intention formation” were the most frequently coded BCTs. Conclusion: Future walking and cycling intervention studies should ensure that all aspects of the intervention are reported in detail. The findings lend support to the inclusion of self-monitoring and intention formation techniques in future walking and cycling intervention design, although further exploration of these and other BCTs is required. Further investigation of the interaction between BCTs and study design characteristics would also be desirable. PMID:23477577

  20. What Can the Habitable Zone Gallery Do For You?

    NASA Astrophysics Data System (ADS)

    Gelino, Dawn M.; Kane, Stephen

    2015-12-01

    The Habitable Zone Gallery (www.hzgallery.org) came online in August 2011 as a service to the exoplanet community that provides Habitable Zone (HZ) information for each of the exoplanetary systems with known planetary orbital parameters. The service includes a sortable table, a plot with the period and eccentricity of each of the planets with respect to their time spent in the HZ, a gallery of known systems which plot the orbits and the location of the HZ with respect to those orbits, and orbital movies. Recently, we have added new features including: implementation of both conservative and optimistic HZs, more user-friendly table and movies, movies for circumbinary planets, and a count of planets whose orbits lie entirely within the system's HZ. Here we discuss various educational and scientific applications of the site such as target selection, exploring planets with eccentric or circumbinary orbits, and investigating habitability.

  1. Phased-array optical whispering gallery mode modulation and method

    NASA Technical Reports Server (NTRS)

    Strekalov, Dmitry V. (Inventor)

    2009-01-01

    A whispering gallery mode (WGM) resonator device and method capable of filtering sidebands of optical modulators are provided. The method includes providing an optical resonator adapted to support whispering gallery modes and forming a first field and a second field from a first location and a second location, respectively, at the circumference of the optical resonator and being separated by an arc angle, .alpha.. The method includes adjusting relative phase between the first field and the second field in accordance to a differential phase, .beta., and combining the first and the second fields into an output. Particular selection of the arc angle, .alpha., and the differential phase, .beta., can determine the function of the output.

  2. Optical pulse propagation via whispering gallery modes in glass spheres

    SciTech Connect

    Whitten, W.B.; Shaw, R.W.; Barnes, M.D.; Ramsey, J.M.

    1997-12-01

    Early in this century, Rayleigh showed that waves could propagate close to the wall of a spherical cavity with very little loss as long as the wavelength was small compared to the cavity circumference. The treatment was primarily for acoustic waves, modeling the whispering gallery effect, but he pointed out that electromagnetic waves should behave similarly. Study of the optical properties of dielectric spheres has received new interest with improvements in optical instrumentation and the emergency of new applications for high-Q resonators. It has recently been shown that optical pulses propagating in whispering gallery modes can be treated analogously to pulses in a fiber optic waveguide. Since the optical fields extend beyond the surface of the sphere, the sphere`s environment could alter propagation properties such as cavity ringdown time. The authors describe here some time and frequency-domain measurements of picosecond pulses in glass spheres of millimeter dimension and discuss potential analytical applications.

  3. Relativistic Weierstrass random walks.

    PubMed

    Saa, Alberto; Venegeroles, Roberto

    2010-08-01

    The Weierstrass random walk is a paradigmatic Markov chain giving rise to a Lévy-type superdiffusive behavior. It is well known that special relativity prevents the arbitrarily high velocities necessary to establish a superdiffusive behavior in any process occurring in Minkowski spacetime, implying, in particular, that any relativistic Markov chain describing spacetime phenomena must be essentially Gaussian. Here, we introduce a simple relativistic extension of the Weierstrass random walk and show that there must exist a transition time t{c} delimiting two qualitative distinct dynamical regimes: the (nonrelativistic) superdiffusive Lévy flights, for tt{c} . Implications of this crossover between different diffusion regimes are discussed for some explicit examples. The study of such an explicit and simple Markov chain can shed some light on several results obtained in much more involved contexts. PMID:20866862

  4. At 1050 Gallery, Block 12, two centrifugal pumps, Buffalo Pumps, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    At 1050 Gallery, Block 12, two centrifugal pumps, Buffalo Pumps, Buffalo, NY, driven by Allis Chalmers motors (size 3 HSO, head 230, 120 cpm, 1750, rpm, Impulse dia. 15) installed in the 1960s and used for water-cooling system for 230-kv cable; the cables have been removed and the pumps are not currently used. - Columbia Basin Project, Grand Coulee Dam & Franklin D. Roosevelt Lake, Across Columbia River, Southeast of Town of Grand Coulee, Grand Coulee, Grant County, WA

  5. Whispering gallery mode resonators based on radiation-sensitive materials

    NASA Technical Reports Server (NTRS)

    Savchenkov, Anatoliy (Inventor); Maleki, Lutfollah (Inventor); Ilchenko, Vladimir (Inventor); Handley, Timothy A. (Inventor)

    2005-01-01

    Whispering gallery mode (WGM) optical resonators formed of radiation-sensitive materials to allow for permanent tuning of their resonance frequencies in a controlled manner. Two WGM resonators may be cascaded to form a composite filter to produce a second order filter function where at least one WGM resonator is formed a radiation-sensitive material to allow for proper control in the overlap of the two filter functions.

  6. Nonlinear optics and crystalline whispering gallery mode resonators

    NASA Technical Reports Server (NTRS)

    Matsko, Andrey B.; Savchenkov, Anatoliy A.; Ilchenko, Vladimir S.; Maleki, Lute

    2004-01-01

    We report on our recent results concerning fabrication of high-Q whispering gallery mode (WGM) crystalline resonators, and discuss some possible applications of lithium niobate WGM resonators in nonlinear optics and photonics. In particular, we demonstrate experimentally a tunable third-order optical filter fabricated from the three metalized resonators; and report observation of parametric frequency dobuling in a WGM resonator made of periodically poled lithium niobate (PPLN).

  7. At 1050 Gallery, Block 55, view of motors for operating ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    At 1050 Gallery, Block 55, view of motors for operating gates of diversion tubes, looking west (Note: the gate control unit to the far right is the one mistakenly left open in 1952 and this led to the flood inside the dam) - Columbia Basin Project, Grand Coulee Dam & Franklin D. Roosevelt Lake, Across Columbia River, Southeast of Town of Grand Coulee, Grand Coulee, Grant County, WA

  8. Graded-Index "Whispering-Gallery" Optical Microresonators

    NASA Technical Reports Server (NTRS)

    Savchenkov, Anatoliy; Maleki, Lute; Iltchenko, Vladimir; Matsko, Andrey

    2006-01-01

    Graded-index-of-refraction dielectric optical microresonators have been proposed as a superior alternative to prior dielectric optical microresonators, which include microspheres and microtori wherein electromagnetic waves propagate along circumferential paths in "whispering-gallery" modes. The design and method of fabrication of the proposed microresonators would afford improved performance by exploiting a combination of the propagation characteristics of the whisperinggallery modes and the effect of a graded index of refraction on the modes.

  9. Walking with springs

    NASA Astrophysics Data System (ADS)

    Sugar, Thomas G.; Hollander, Kevin W.; Hitt, Joseph K.

    2011-04-01

    Developing bionic ankles poses great challenges due to the large moment, power, and energy that are required at the ankle. Researchers have added springs in series with a motor to reduce the peak power and energy requirements of a robotic ankle. We developed a "robotic tendon" that reduces the peak power by altering the required motor speed. By changing the required speed, the spring acts as a "load variable transmission." If a simple motor/gearbox solution is used, one walking step would require 38.8J and a peak motor power of 257 W. Using an optimized robotic tendon, the energy required is 21.2 J and the peak motor power is reduced to 96.6 W. We show that adding a passive spring in parallel with the robotic tendon reduces peak loads but the power and energy increase. Adding a passive spring in series with the robotic tendon reduces the energy requirements. We have built a prosthetic ankle SPARKy, Spring Ankle with Regenerative Kinetics, that allows a user to walk forwards, backwards, ascend and descend stairs, walk up and down slopes as well as jog.

  10. Whispering gallery resonators with broken axial symmetry: Theory and experiment.

    PubMed

    Fürst, J; Sturman, B; Buse, K; Breunig, I

    2016-09-01

    Axial symmetry is the cornerstone for theory and applications of high-Q optical whispering gallery resonators (WGRs). Nevertheless, research on birefringent crystalline material persistently pushes towards breaking this symmetry. We show theoretically and experimentally that the effect of broken axial symmetry, caused by optical anisotropy, is modest for the resonant frequencies and Q-factors of the WGR modes. Thus, the most important equatorial whispering gallery modes can be quantitatively described and experimentally identified. At the same time, the effect of broken axial symmetry on the light field distribution of the whispering gallery modes is typically very strong. This qualitatively modifies the phase-matching for the χ(2) nonlinear processes and enables broad-band second harmonic generation and optical parametric oscillation. The effect of weak geometric ellipticity in nominally symmetric WGRs is also considered. Altogether our findings pave the way for an extensive use of numerous birefringent (uniaxial and biaxial) crystals with broad transparency window and large χ(2) coefficients in nonlinear optics with WGRs. PMID:27607622

  11. A gallery approach for off-angle iris recognition

    NASA Astrophysics Data System (ADS)

    Karakaya, Mahmut; Yoldash, Rashiduddin; Boehnen, Christopher

    2015-05-01

    It has been proven that hamming distance score between frontal and off-angle iris images of same eye differs in iris recognition system. The distinction of hamming distance score is caused by many factors such as image acquisition angle, occlusion, pupil dilation, and limbus effect. In this paper, we first study the effect of the angle variations between iris plane and the image acquisition systems. We present how hamming distance changes for different off-angle iris images even if they are coming from the same iris. We observe that increment in acquisition angle of compared iris images causes the increment in hamming distance. Second, we propose a new technique in off-angle iris recognition system that includes creating a gallery of different off-angle iris images (such as, 0, 10, 20, 30, 40, and 50 degrees) and comparing each probe image with these gallery images. We will show the accuracy of the gallery approach for off-angle iris recognition.

  12. Backward Walking in Parkinson Disease

    PubMed Central

    Hackney, Madeleine E.; Earhart, Gammon M.

    2010-01-01

    We walk backward on a daily basis, such as when backing away from the kitchen sink or stepping back from a curb as a swiftly moving bus passes. This task may be particularly difficult for individuals with PD who often fall as a result of moving or being perturbed in the backward direction (Horak et al. 2005, Bloem et al 2004). The aim of this study was to assess backward walking in individuals with PD. Both forward and backward gait were assessed in 78 people with idiopathic PD (H&Y range: 0.5–3) in the ON state, and 74 age- and sex-matched controls. In forward walking, those with PD had significantly shorter strides, lower swing percents, higher stance percents and lower functional ambulation profiles than controls. Both groups walked significantly slower and with a wider base of support during backward walking than forward walking. Additionally, in backward walking those with PD walked significantly slower with shorter strides, lower swing percents, and higher double support and stance percents, and lower functional ambulation profiles compared to controls. Those with mild to moderate PD have impaired forward and backward walking, but differences between those with and without PD are more pronounced in backward walking. PMID:18951535

  13. Walking Tours for Teaching Urban History in Boston and Other Cities.

    ERIC Educational Resources Information Center

    Holton, William

    1990-01-01

    Recommends integrating urban history curricular concepts into walking tours. Uses an ecosystem model, combining factors of population, environment, and technology to teach these concepts. Suggests study questions be prepared for tours such as the South End Walking Tour in Boston to teach concepts by experiencing them in the urban environment.…

  14. eFluids Video Gallery: a ``YouTube'' for Fluid Mechanics

    NASA Astrophysics Data System (ADS)

    Smits, Alexander

    2008-11-01

    The research and educational value of videos of fluid mechanical phenomena cannot be overstated, yet there are literally hundreds of videos that, while posted on various websites, can be difficult to find. eFluids.com has launched a new video gallery website highlighting all aspects of fluid mechanics that will hopefully serve as a repository for this material. The gallery receives submissions using a user-friendly interface modeled on the popular YouTube site. Submissions can be in any format and any size up 50MB and up to 5 minutes long. The galleries are searchable and are classified in 23 categories, including subject-specific categories such as ``Laminar Flow,'' ``Turbulence,'' ``Vortices,'' ``Biological Flows,'' etc., as well as ``Recent Postings'' and links to fluids videos on other sites such as YouTube. The Video Gallery is integrated with the other Galleries on eFluids, including the long-established Gallery of Images, Gallery of Experiments, and Gallery of Problems. The presentation will show examples, demonstrate the submission interface, and the integration with the other galleries. In collaboration with George Homsy and Gordon McCreigh, www.eFluids.com.

  15. Agile Walking Robot

    NASA Technical Reports Server (NTRS)

    Larimer, Stanley J.; Lisec, Thomas R.; Spiessbach, Andrew J.; Waldron, Kenneth J.

    1990-01-01

    Proposed agile walking robot operates over rocky, sandy, and sloping terrain. Offers stability and climbing ability superior to other conceptual mobile robots. Equipped with six articulated legs like those of insect, continually feels ground under leg before applying weight to it. If leg sensed unexpected object or failed to make contact with ground at expected point, seeks alternative position within radius of 20 cm. Failing that, robot halts, examines area around foot in detail with laser ranging imager, and replans entire cycle of steps for all legs before proceeding.

  16. Qualitative developmental research among low income African American adults to inform a social marketing campaign for walking

    PubMed Central

    2013-01-01

    Background This study describes the development of a social marketing campaign for increasing walking in a low income, high crime community as part of the Positive Action for Today’s Health (PATH) trial. Methods Focus groups were conducted with 52 African American adults (ages 18 to 65 yrs), from two underserved communities to develop themes for a social marketing campaign to promote walking. Participants responded to questions concerning social marketing principles related to product, price, place, promotion, and positioning for increasing neighbourhood walking. Results Focus group data informed the development of the campaign objectives that were derived from the “5 Ps” to promote physical and mental health, social connectedness, safety, and confidence in walking regularly. Focus group themes indicated that physical and mental health benefits of walking were important motivators. Walking for social reasons was also important for overcoming barriers to walking. Police support from trusted officers while walking was also essential to promoting safety for walking. Print materials were developed by the steering committee, with a 12-month calendar and door hangers delivered to residents’ homes to invite them to walk. Pride Stride walks empowered community walkers to serve as peer leaders for special walking events to engage new walkers. Conclusions Essential elements for developing culturally tailored social marketing interventions for promoting walking in underserved communities are outlined for future researchers. PMID:23497164

  17. Random-walk enzymes

    NASA Astrophysics Data System (ADS)

    Mak, Chi H.; Pham, Phuong; Afif, Samir A.; Goodman, Myron F.

    2015-09-01

    Enzymes that rely on random walk to search for substrate targets in a heterogeneously dispersed medium can leave behind complex spatial profiles of their catalyzed conversions. The catalytic signatures of these random-walk enzymes are the result of two coupled stochastic processes: scanning and catalysis. Here we develop analytical models to understand the conversion profiles produced by these enzymes, comparing an intrusive model, in which scanning and catalysis are tightly coupled, against a loosely coupled passive model. Diagrammatic theory and path-integral solutions of these models revealed clearly distinct predictions. Comparison to experimental data from catalyzed deaminations deposited on single-stranded DNA by the enzyme activation-induced deoxycytidine deaminase (AID) demonstrates that catalysis and diffusion are strongly intertwined, where the chemical conversions give rise to new stochastic trajectories that were absent if the substrate DNA was homogeneous. The C →U deamination profiles in both analytical predictions and experiments exhibit a strong contextual dependence, where the conversion rate of each target site is strongly contingent on the identities of other surrounding targets, with the intrusive model showing an excellent fit to the data. These methods can be applied to deduce sequence-dependent catalytic signatures of other DNA modification enzymes, with potential applications to cancer, gene regulation, and epigenetics.

  18. Random-walk enzymes

    PubMed Central

    Mak, Chi H.; Pham, Phuong; Afif, Samir A.; Goodman, Myron F.

    2015-01-01

    Enzymes that rely on random walk to search for substrate targets in a heterogeneously dispersed medium can leave behind complex spatial profiles of their catalyzed conversions. The catalytic signatures of these random-walk enzymes are the result of two coupled stochastic processes: scanning and catalysis. Here we develop analytical models to understand the conversion profiles produced by these enzymes, comparing an intrusive model, in which scanning and catalysis are tightly coupled, against a loosely coupled passive model. Diagrammatic theory and path-integral solutions of these models revealed clearly distinct predictions. Comparison to experimental data from catalyzed deaminations deposited on single-stranded DNA by the enzyme activation-induced deoxycytidine deaminase (AID) demonstrates that catalysis and diffusion are strongly intertwined, where the chemical conversions give rise to new stochastic trajectories that were absent if the substrate DNA was homogeneous. The C → U deamination profiles in both analytical predictions and experiments exhibit a strong contextual dependence, where the conversion rate of each target site is strongly contingent on the identities of other surrounding targets, with the intrusive model showing an excellent fit to the data. These methods can be applied to deduce sequence-dependent catalytic signatures of other DNA modification enzymes, with potential applications to cancer, gene regulation, and epigenetics. PMID:26465508

  19. Quantum stochastic walks: A generalization of classical random walks and quantum walks

    NASA Astrophysics Data System (ADS)

    Whitfield, James D.; Rodríguez-Rosario, César A.; Aspuru-Guzik, Alán

    2010-02-01

    We introduce the quantum stochastic walk (QSW), which determines the evolution of a generalized quantum-mechanical walk on a graph that obeys a quantum stochastic equation of motion. Using an axiomatic approach, we specify the rules for all possible quantum, classical, and quantum-stochastic transitions from a vertex as defined by its connectivity. We show how the family of possible QSWs encompasses both the classical random walk (CRW) and the quantum walk (QW) as special cases but also includes more general probability distributions. As an example, we study the QSW on a line and the glued tree of depth three to observe the behavior of the QW-to-CRW transition.

  20. Barriers to Walking: An Investigation of Adults in Hamilton (Ontario, Canada)

    PubMed Central

    Clark, Andrew F.; Scott, Darren M.

    2016-01-01

    This study investigates perceived barriers to walking using data collected from 179 randomly-selected adults between the ages of 18 and 92 in Hamilton, Ontario, Canada. A survey (Hamilton Active Living Study) asked questions about socio-demographics, walking, and barriers to walking. A series of binary logit models are estimated for twenty potential barriers to walking. The results demonstrate that different barriers are associated with different sub-groups of the population. Females, senior citizens, and those with a higher body mass index identify the most barriers to walking, while young adults, parents, driver’s license owners, and bus pass owners identify the fewest barriers. Understanding who is affected by perceived barriers can help policy makers and health promotion agencies target sub-groups of the population in an effort to increase walking. PMID:26840328

  1. Cavemen Were Better at Depicting Quadruped Walking than Modern Artists: Erroneous Walking Illustrations in the Fine Arts from Prehistory to Today

    PubMed Central

    Horvath, Gabor; Farkas, Etelka; Boncz, Ildiko; Blaho, Miklos; Kriska, Gyorgy

    2012-01-01

    The experts of animal locomotion well know the characteristics of quadruped walking since the pioneering work of Eadweard Muybridge in the 1880s. Most of the quadrupeds advance their legs in the same lateral sequence when walking, and only the timing of their supporting feet differ more or less. How did this scientific knowledge influence the correctness of quadruped walking depictions in the fine arts? Did the proportion of erroneous quadruped walking illustrations relative to their total number (i.e. error rate) decrease after Muybridge? How correctly have cavemen (upper palaeolithic Homo sapiens) illustrated the walking of their quadruped prey in prehistoric times? The aim of this work is to answer these questions. We have analyzed 1000 prehistoric and modern artistic quadruped walking depictions and determined whether they are correct or not in respect of the limb attitudes presented, assuming that the other aspects of depictions used to determine the animals gait are illustrated correctly. The error rate of modern pre-Muybridgean quadruped walking illustrations was 83.5%, much more than the error rate of 73.3% of mere chance. It decreased to 57.9% after 1887, that is in the post-Muybridgean period. Most surprisingly, the prehistoric quadruped walking depictions had the lowest error rate of 46.2%. All these differences were statistically significant. Thus, cavemen were more keenly aware of the slower motion of their prey animals and illustrated quadruped walking more precisely than later artists. PMID:23227149

  2. A contribution to film coefficient estimation in piston cooling galleries

    SciTech Connect

    Torregrosa, A.J.; Broatch, A.; Olmeda, P.; Martin, J.

    2010-02-15

    The need to reduce fuel consumption and exhaust emissions in internal combustion engines has been drastically increased during last years. One of the most important processes affecting these parameters is heat transfer from the in-cylinder gas to the surrounding walls, as this mechanism has a direct influence on the combustion process. Regarding the different walls (liner, cylinder head and piston surfaces), heat flow to the piston is especially important, as it is essential to avoid excessively high temperatures that could result in material damage and/or oil cracking. With this purpose different cooling strategies are used, among which the improvement of the piston cooling system by using oil galleries is preferred. In this work, the heat flow through the oil gallery in a Diesel piston was investigated on a dedicated test bench. This bench consists of a controlled heat source and a piston oil cooling system in which different test conditions were evaluated in order to obtain a correlation for the film coefficient associated with piston oil cooling. These experimental results were then incorporated into a lumped model for engine heat transfer. Finally, in order to evaluate the accuracy of this model and the effects of the correlation for oil gallery coefficient on engine heat flows, results obtained on a conventional engine test bench equipped with a Diesel engine, in which two piston temperatures had been measured, were used. The results show an improvement in piston temperature predictions when compared with those obtained using a previously reported expression for the calculation of the oil film coefficient. (author)

  3. STAR Images: Image gallery from the Solenoidal Tracker at RHIC

    DOE Data Explorer

    The primary physics task of STAR is to study the formation and characteristics of the quark-gluon plasma (QGP), a state of matter believed to exist at sufficiently high energy densities. STAR consists of several types of detectors, each specializing in detecting certain types of particles or characterizing their motion. These detectors allow final statements to be made about the collision. The gallery of STAR images makes available a small collection of event-generated images from Gold-Beam experiments, a simulation of TCP Drift, and a library of STAR instrument and construction photos.

  4. High-Q silk fibroin whispering gallery microresonator.

    PubMed

    Xu, Linhua; Jiang, Xuefeng; Zhao, Guangming; Ma, Ding; Tao, Hu; Liu, Zhiwen; Omenetto, Fiorenzo G; Yang, Lan

    2016-09-01

    We have experimentally demonstrated an on-chip all-silk fibroin whispering gallery mode microresonator by using a simple molding and solution-casting technique. The quality factors of the fabricated silk protein microresonators are on the order of 105. A high-sensitivity thermal sensor was realized in this silk fibroin microtoroid with a sensitivity of -1.17 nm/K, that is 8 times higher than previous WGM resonator-based thermal sensors. This opens the way to fabricate biodegradable and biocompatible protein based microresonators on a flexible chip for biophotonics applications. PMID:27607686

  5. Opto-acoustic phenomena in whispering gallery mode resonators

    NASA Astrophysics Data System (ADS)

    Lin, Guoping; Chembo, Yanne K.

    2016-01-01

    Optical whispering gallery mode resonators are important platforms to enhance and study various nonlinear frequency conversion processes. Stimulated Brillouin scattering is one of the strongest nonlinear effects, and can be successfully investigated using these platforms. In this article, we study the phenomenon of stimulated Brillouin scattering using a crystalline disk resonator. A fast scanning ringdown spectroscopy technique is used to characterize the optical modes featuring quality factors of the order of one billion at telecom wavelengths. The mW scale threshold power in a centimeter disk resonator is observed and found to be strongly dependent on the gap between the resonator and the prism coupler.

  6. Observation of whispering gallery modes in microtube-microspheres system

    NASA Astrophysics Data System (ADS)

    Li, Hanyang; Hao, Sue; Qiang, Liangsheng; Li, Jin; Zhang, Yundong

    2013-06-01

    We proposed that a fluorescent microsphere with diameter of 6 μm was manipulated into a microtube with inner diameter of 6.2 μm. The whispering gallery modes (WGMs) of fluorescence resonance were observed by 532 nm laser pumping the microspheres-mircotube system. Another microsphere with the same diameter was manipulated into the microtube and mode splitting in the system of two spheres in contact in the mircotube was demonstrated. We also discussed relationship between WGMs peak intensity and the excitation power. The scheme will bring more insight into the applications of WGMs for biomedical diagnostics and microfluidics.

  7. Method of fabricating a whispering gallery mode resonator

    NASA Technical Reports Server (NTRS)

    Savchenkov, Anatoliy A. (Inventor); Matkso, Andrey B. (Inventor); Iltchenko, Vladimir S. (Inventor); Maleki, Lute (Inventor)

    2011-01-01

    A method of fabricating a whispering gallery mode resonator (WGMR) is provided. The WGMR can be fabricated from a particular material, annealed, and then polished. The WGMR can be repeatedly annealed and then polished. The repeated polishing of the WGMR can be carried out using an abrasive slurry. The abrasive slurry can have a predetermined, constant grain size. Each subsequent polishing of the WGMR can use an abrasive slurry having a grain size that is smaller than the grain size of the abrasive slurry of the previous polishing iteration.

  8. Blue-pumped whispering gallery optical parametric oscillator.

    PubMed

    Werner, Christoph Sebastian; Beckmann, Tobias; Buse, Karsten; Breunig, Ingo

    2012-10-15

    We demonstrate a whispering gallery optical parametric oscillator pumped at 488 nm wavelength. This millimeter-sized device has a pump threshold of 160 μW. The signal field is tunable between 707 and 865 nm wavelength and the idler field between 1120 and 1575 nm through temperature variation. Although the conversion efficiency is fundamentally limited to several percent because of absorption loss for the pump wave, the results provide evidence that such oscillators will be able to cover finally the entire visible range. PMID:23073418

  9. Endless self-avoiding walks

    NASA Astrophysics Data System (ADS)

    Clisby, Nathan

    2013-06-01

    We introduce a self-avoiding walk model for which end-effects are completely eliminated. We enumerate the number of these walks for various lattices in dimensions two and three, and use these enumerations to study the properties of this model. We find that endless self-avoiding walks have the same connective constant as self-avoiding walks, and the same Flory exponent ν. However, there is no power law correction to the exponential number growth for this new model, i.e. the critical exponent γ = 1 exactly in any dimension. In addition, the number growth has no analytic corrections to scaling, and we have convincing numerical evidence to support the conjecture that the amplitude for the number growth is a universal quantity. The technique by which end-effects are eliminated may be generalized to other models of polymers such as interacting self-avoiding walks.

  10. Whispering gallery modes in a spherical microcavity with a photoluminescent shell

    SciTech Connect

    Grudinkin, S. A. Dontsov, A. A.; Feoktistov, N. A.; Baranov, M. A.; Bogdanov, K. V.; Averkiev, N. S.; Golubev, V. G.

    2015-10-15

    Whispering-gallery mode spectra in optical microcavities based on spherical silica particles coated with a thin photoluminescent shell of hydrogenated amorphous silicon carbide are studied. The spectral positions of the whispering-gallery modes for spherical microcavities with a shell are calculated. The dependence of the spectral distance between the TE and TM modes on the shell thickness is examined.

  11. Perceptions of Pre-Service Teachers Value of Art Museums and Galleries

    ERIC Educational Resources Information Center

    Lemon, Narelle; Garvis, Susanne

    2014-01-01

    Art museums and galleries provide many educational opportunities for generalist classroom teachers to engage in learning experiences with students. Beliefs about engagement with art museums and galleries can begin in teacher education programs. This paper explores the beliefs of pre-service teachers in a Bachelor of Education (primary) program in…

  12. Inclusive Art Gallery Practices: Exploring Collaborative Processes and Pedagogy in Outreach Community Programming

    ERIC Educational Resources Information Center

    Reid, Natasha

    2011-01-01

    Currently, many museums and galleries are attempting to create more welcoming and meaningful experiences for individuals who tend to be reluctant to enter and participate in these institutions. Art galleries and museums are examining and experimenting with ways to connect diverse publics through socially inclusive community outreach programs. This…

  13. Voice, Choice, Equity and Access: Young Children Capture Their Art Gallery Education Experiences

    ERIC Educational Resources Information Center

    Lemon, Narelle

    2013-01-01

    Introducing a digital camera in the art gallery space is somewhat confrontational. Most museums have strict protocols on what can and cannot be captured. From the educational perspective it does, however, offer a new and innovative way of working that supports young people's ability to record what they see and how they experience the gallery, the…

  14. The Art Gallery/La Galeria de Arte: An Exhibition of Transformation.

    ERIC Educational Resources Information Center

    Biagi, Juliet

    2001-01-01

    Describes the development of an art gallery within an urban elementary school, examining its impact on diverse students and their social interactions at school and home. The gallery had a positive impact on students (improved self-esteem, motivation, and appreciation of others); the school (transformation of the physical space and appreciation of…

  15. Communities of Practice in Art and Design and Museum and Gallery Education

    ERIC Educational Resources Information Center

    Herne, Steve

    2006-01-01

    This article draws on a wider body of research that explores whether art and design teachers (art teachers) and museum and gallery educators (gallery educators) hold conflicting conceptions of "critical and contextual studies". The data analysis focuses on what interviewees said about each other in relation to crossing boundaries between…

  16. Using Sense to Make Sense of Art: Young Children in Art Galleries

    ERIC Educational Resources Information Center

    MacRae, Christina

    2007-01-01

    This paper reflects on a collaborative project between Manchester City Art Gallery and Manchester Metropolitan University (2003-2004). The project's aim was to attract very young children and their families to the gallery. This paper will not report directly on the research methods used or the outcomes of the project but, rather, will explore…

  17. The Portable Art Gallery: Fostering Student Ownership and Meaningful Artmaking through Exhibiting Student Artwork

    ERIC Educational Resources Information Center

    Gillespie, Jethro

    2014-01-01

    This article describes how High School Visual Arts Teacher Jethro Gillespie built a portable art gallery for his students--essentially an 8-foot cube made from plywood and lightweight boards that can be assembled with bolts and taken apart in sections. The ceiling pieces of the gallery have track lights, the interior walls have been painted gray,…

  18. Quantum walks on quotient graphs

    SciTech Connect

    Krovi, Hari; Brun, Todd A.

    2007-06-15

    A discrete-time quantum walk on a graph {gamma} is the repeated application of a unitary evolution operator to a Hilbert space corresponding to the graph. If this unitary evolution operator has an associated group of symmetries, then for certain initial states the walk will be confined to a subspace of the original Hilbert space. Symmetries of the original graph, given by its automorphism group, can be inherited by the evolution operator. We show that a quantum walk confined to the subspace corresponding to this symmetry group can be seen as a different quantum walk on a smaller quotient graph. We give an explicit construction of the quotient graph for any subgroup H of the automorphism group and illustrate it with examples. The automorphisms of the quotient graph which are inherited from the original graph are the original automorphism group modulo the subgroup H used to construct it. The quotient graph is constructed by removing the symmetries of the subgroup H from the original graph. We then analyze the behavior of hitting times on quotient graphs. Hitting time is the average time it takes a walk to reach a given final vertex from a given initial vertex. It has been shown in earlier work [Phys. Rev. A 74, 042334 (2006)] that the hitting time for certain initial states of a quantum walks can be infinite, in contrast to classical random walks. We give a condition which determines whether the quotient graph has infinite hitting times given that they exist in the original graph. We apply this condition for the examples discussed and determine which quotient graphs have infinite hitting times. All known examples of quantum walks with hitting times which are short compared to classical random walks correspond to systems with quotient graphs much smaller than the original graph; we conjecture that the existence of a small quotient graph with finite hitting times is necessary for a walk to exhibit a quantum speedup.

  19. When to walk away from a deal.

    PubMed

    Cullinan, Geoffrey; Le Roux, Jean-Marc; Weddigen, Rolf-Magnus

    2004-04-01

    Deal making is glamorous; due diligence is not. That simple statement goes a long way toward explaining why so many companies have made so many acquisitions that have produced so little value. The momentum of a transaction is hard to resist once senior management has the target in its sights. Companies contract "deal fever," and due diligence all too often becomes an exercise in verifying the target's financial statements rather than conducting a fair analysis of the deal's strategic logic and the acquirer's ability to realize value from it. Seldom does the process lead managers to kill potential acquisitions, even when the deals are deeply flawed. In a recent Bain & Company survey of 250 international executives with M&A responsibilities, only 30% of them were satisfied with the rigor of their due diligence. And fully a third admitted they hadn't walked away from deals they had nagging doubts about. In this article, the authors, all Bain consultants, emphasize the importance of comprehensive due diligence practices and suggest ways companies can improve their capabilities in this area. They provide rich real-world examples of companies that have had varying levels of success with their due diligence processes, including Safeway, Odeon, American Sea-foods, and Kellogg's. Effective due diligence requires answering four basic questions: What are we really buying? What is the target's stand-alone value? Where are the synergies--and the skeletons? And what's our walk-away price? Each of these questions will prompt an even deeper level of querying that puts the broader, strategic rationale for acquisitions under a microscope. Successful acquirers pay close heed to the results of such in-depth investigations and analyses--to the extent that they are prepared to walk away from a deal, even in the very late stages of negotiations. PMID:15077370

  20. Walking indoors, walking outdoors: an fMRI study

    PubMed Central

    Dalla Volta, Riccardo; Fasano, Fabrizio; Cerasa, Antonio; Mangone, Graziella; Quattrone, Aldo; Buccino, Giovanni

    2015-01-01

    An observation/execution matching system for walking has not been assessed yet. The present fMRI study was aimed at assessing whether, as for object-directed actions, an observation/execution matching system is active for walking and whether the spatial context of walking (open or narrow space) recruits different neural correlates. Two experimental conditions were employed. In the execution condition, while being scanned, participants performed walking on a rolling cylinder located just outside the scanner. The same action was performed also while observing a video presenting either an open space (a country field) or a narrow space (a corridor). In the observation condition, participants observed a video presenting an individual walking on the same cylinder on which the actual action was executed, the open space video and the narrow space video, respectively. Results showed common bilateral activations in the dorsal premotor/supplementary motor areas and in the posterior parietal lobe for both execution and observation of walking, thus supporting a matching system for this action. Moreover, specific sectors of the occipital–temporal cortex and the middle temporal gyrus were consistently active when processing a narrow space versus an open one, thus suggesting their involvement in the visuo-motor transformation required when walking in a narrow space. We forward that the present findings may have implications for rehabilitation of gait and sport training. PMID:26483745

  1. Comparison of heart rate responses. Water walking versus treadmill walking.

    PubMed

    Whitley, J D; Schoene, L L

    1987-10-01

    The purpose of this study was to compare heart rate responses to water walking versus treadmill walking to determine whether the responses were of sufficient magnitude to elicit cardiorespiratory training effects. The heart rates of 12 healthy, female college students were measured immediately after walking in waist-deep water and on a treadmill at the same distance, durations, and speeds (2.55, 2.77, 3.02, and 3.31 km/hr). A significant increase in heart rate with increased speeds resulted from water walking (p less than .05); from rest to the fastest speed, it was 135% (96 bpm). For treadmill walking, the increase of 19% (13 bpm) was not significant. The heart rates for the water condition were significantly higher (p less than .05) at each speed. These findings indicate that water walking could serve as an effective exercise mode, for example, for cardiorespiratory fitness for individuals who are unable to perform such weight-bearing activities as jogging, fast walking, cycling, and dancing. PMID:3659133

  2. Diffraction of walking droplets

    NASA Astrophysics Data System (ADS)

    Harris, Daniel M.; Pucci, Giuseppe; Bush, John W. M.

    2014-11-01

    We present results from our revisitation of the experiment of a walking droplet passing through a single slit, originally investigated by Couder & Fort (PRL, 2006). On each passage, the walker's trajectory is deviated as a result of the spatial confinement of its guiding wave. We explore the role of the droplet size and the bath's vibration amplitude on both the dynamics and statistics. We find the behavior to be remarkably sensitive to these control parameters. A complex physical picture emerges. The authors gratefully acknowledge the financial support of the NSF through Grant CMMI-1333242, DMH through the NSF Graduate Research Fellowship Program, and GP through the Programma Operativo Regionale (POR) Calabria - FSE 2007/2013.

  3. Water-walking devices

    NASA Astrophysics Data System (ADS)

    Hu, David L.; Prakash, Manu; Chan, Brian; Bush, John W. M.

    2007-11-01

    We report recent efforts in the design and construction of water-walking machines inspired by insects and spiders. The fundamental physical constraints on the size, proportion and dynamics of natural water-walkers are enumerated and used as design criteria for analogous mechanical devices. We report devices capable of rowing along the surface, leaping off the surface and climbing menisci by deforming the free surface. The most critical design constraint is that the devices be lightweight and non-wetting. Microscale manufacturing techniques and new man-made materials such as hydrophobic coatings and thermally actuated wires are implemented. Using high-speed cinematography and flow visualization, we compare the functionality and dynamics of our devices with those of their natural counterparts.

  4. Water-walking devices

    NASA Astrophysics Data System (ADS)

    Hu, David L.; Prakash, Manu; Chan, Brian; Bush, John W. M.

    We report recent efforts in the design and construction of water-walking machines inspired by insects and spiders. The fundamental physical constraints on the size, proportion and dynamics of natural water-walkers are enumerated and used as design criteria for analogous mechanical devices. We report devices capable of rowing along the surface, leaping off the surface and climbing menisci by deforming the free surface. The most critical design constraint is that the devices be lightweight and non-wetting. Microscale manufacturing techniques and new man-made materials such as hydrophobic coatings and thermally actuated wires are implemented. Using highspeed cinematography and flow visualization, we compare the functionality and dynamics of our devices with those of their natural counterparts.

  5. Virtual gallery of ancient coins through conoscopic holography

    NASA Astrophysics Data System (ADS)

    Schirripa Spagnolo, Giuseppe; Majo, Raffaele; Carli, Marco; Ambrosini, Dario; Paoletti, Domenica

    2003-10-01

    Physical access to historic and artistic manufactures can be limited by a lot of factors. In particular, the access to the collection of the ancient coins is difficult, especially for students. Indeed, for coins digital archive of high quality three-dimensional model and remote fruition is of great interest. In this work we propose 3D acquisition and digitizing techniques for the virtualized reality of ancient coins (virtual gallery). The system used for creating 3D shape of coins is based on conoscopic holography. This technique is a non-contact three-dimensional measuring technique that makes possible to produce holograms, even with incoherent light, with fringe periods that can be measured precisely to determine the exact distance to the point measured. It is suitable to obtain 3D profile with high resolution also on surface with unevenness reflectivity (this situation is usual on the surface of the ancient coins). By conoscopic holography, high-resolution 3D model can be obtained. However, accurate representation and high-quality display are fundamental requirements to avoid misinterpretation of the data. Therefore, virtual galleries can be obtained through a procedure involving 3D acquisition, 3D model and visualization. In conclusion, we propose an optoelectronic application, integrated with multimedia techniques, in order to improve the access to collection of ancient coins belonging to museums or privates.

  6. Quantum stochastic walks: A generalization of classical random walks and quantum walks

    NASA Astrophysics Data System (ADS)

    Aspuru-Guzik, Alan

    2010-03-01

    We introduce the quantum stochastic walk (QSW), which determines the evolution of generalized quantum mechanical walk on a graph that obeys a quantum stochastic equation of motion. Using an axiomatic approach, we specify the rules for all possible quantum, classical and quantum-stochastic transitions from a vertex as defined by its connectivity. We show how the family of possible QSWs encompasses both the classical random walk (CRW) and the quantum walk (QW) as special cases, but also includes more general probability distributions. As an example, we study the QSW on a line, the QW to CRW transition and transitions to genearlized QSWs that go beyond the CRW and QW. QSWs provide a new framework to the study of quantum algorithms as well as of quantum walks with environmental effects.

  7. What is the password? Female bark beetles (Scolytinae) grant males access to their galleries based on courtship song.

    PubMed

    Lindeman, Amanda A; Yack, Jayne E

    2015-06-01

    Acoustic signals are commonly used by insects in the context of mating, and signals can vary depending on the stage of interaction between a male and female. While calling songs have been studied extensively, particularly in the Orthoptera, much less is known about courtship songs. One outstanding question is how potential mates are differentiated by their courtship signal characteristics. We examined acoustic courtship signals in a new system, bark beetles (Scolytinae). In the red turpentine beetle (Dendroctonus valens) males produce chirp trains upon approaching the entrance of a female's gallery. We tested the hypotheses that acoustic signals are honest indicators of male condition and that females choose males based on signal characteristics. Males generated two distinct chirp types (simple and interrupted), and variability in their prevalence correlated with an indicator of male quality, body size, with larger males producing significantly more interrupted chirps. Females showed a significant preference for males who produced interrupted chirps, suggesting that females distinguish between males on the basis of their chirp performances. We suggest that interrupted chirps during courtship advertise a male's size and/or motor skills, and function as the proverbial 'passwords' that allow him entry to a female's gallery. PMID:25783802

  8. Sex ratio and female sexual status of the coconut pest, Oryctes monoceros (Coleoptera: Dynastidae), differ in feeding galleries and pheromone-baited traps.

    PubMed

    Allou, K; Morin, J-P; Kouassi, P; Hala N'klo, F; Rochat, D

    2008-12-01

    Oryctes monoceros is a serious coconut pest, causing up to 40% damage in tropical Africa. Synthetic aggregation pheromone, ethyl 4-methyloctanoate, has been used to lure adults to traps. Traps with pheromone plus decaying palm material captured a high proportion of males. This raises the question whether individuals, which damage palms are receptive to the pheromone. We studied the sex ratio of the insects feeding on coconuts and those attracted to pheromone traps. Sixty two percent of adults from feeding galleries on living coconut palms were females. Pheromone with rotting palm material lured 43% females. To investigate the reasons for this difference, we compared the reproductive system of females lured to the odour traps or feeding in coconut galleries, or present in old rotting stems. Ninety six percent of the females trapped by pheromone had mated, and were sexually mature. In the galleries on living palms, 46% of females were immature, and 24% had not mated. In old rotting stems where eggs are laid and larvae develop, a mixture of 52% mated and 48% virgin females was found. Therefore, the pheromone together with the odour of rotting coconut stems signals a reproduction site to beetles, particularly mature females. In practice, the pheromone-baited traps will help in reducing the dissemination of gravid females, but will not affect directly the numbers of immature ones attacking palms. Our results show that when using pheromones for monitoring or controlling insects, the physiological status of the insects may have unexpected effects on the outcome. PMID:18662429

  9. Walking pilgrimage as caritas action in the world.

    PubMed

    Watson, Jean

    2006-12-01

    This essay draws on the personal experiences of a spiritual pilgrimage in northern Spain. Using pilgrimage as metaphor and the experience of walking a portion of the famous Spanish El Camino, (the way), the author raises questions such as: How do we walk through life? How do we get our footing to bring artistry of caring into our lives and work and world? What steps do we take that speak to who we are and our raison d'être? This perspective is grounded in Newman's health as evolving consciousness, Rogers's science of unitary being, Quinn's view of sacred space, and Watson's caritas (cosmic loving consciousness) as the highest form of consciousness, and the infinite source of healing/wholeness. A walking spiritual pilgrimage serves as metaphoric invitation for nurses and nursing to engage in conscious, creative, artful steps, imprinting self and society with caritas in our lives, our work, and our world. PMID:17098883

  10. Comparing Algorithms for Graph Isomorphism Using Discrete- and Continuous-Time Quantum Random Walks

    SciTech Connect

    Rudinger, Kenneth; Gamble, John King; Bach, Eric; Friesen, Mark; Joynt, Robert; Coppersmith, S. N.

    2013-07-01

    Berry and Wang [Phys. Rev. A 83, 042317 (2011)] show numerically that a discrete-time quan- tum random walk of two noninteracting particles is able to distinguish some non-isomorphic strongly regular graphs from the same family. Here we analytically demonstrate how it is possible for these walks to distinguish such graphs, while continuous-time quantum walks of two noninteracting parti- cles cannot. We show analytically and numerically that even single-particle discrete-time quantum random walks can distinguish some strongly regular graphs, though not as many as two-particle noninteracting discrete-time walks. Additionally, we demonstrate how, given the same quantum random walk, subtle di erences in the graph certi cate construction algorithm can nontrivially im- pact the walk's distinguishing power. We also show that no continuous-time walk of a xed number of particles can distinguish all strongly regular graphs when used in conjunction with any of the graph certi cates we consider. We extend this constraint to discrete-time walks of xed numbers of noninteracting particles for one kind of graph certi cate; it remains an open question as to whether or not this constraint applies to the other graph certi cates we consider.

  11. Comparing Algorithms for Graph Isomorphism Using Discrete- and Continuous-Time Quantum Random Walks

    DOE PAGESBeta

    Rudinger, Kenneth; Gamble, John King; Bach, Eric; Friesen, Mark; Joynt, Robert; Coppersmith, S. N.

    2013-07-01

    Berry and Wang [Phys. Rev. A 83, 042317 (2011)] show numerically that a discrete-time quan- tum random walk of two noninteracting particles is able to distinguish some non-isomorphic strongly regular graphs from the same family. Here we analytically demonstrate how it is possible for these walks to distinguish such graphs, while continuous-time quantum walks of two noninteracting parti- cles cannot. We show analytically and numerically that even single-particle discrete-time quantum random walks can distinguish some strongly regular graphs, though not as many as two-particle noninteracting discrete-time walks. Additionally, we demonstrate how, given the same quantum random walk, subtle di erencesmore » in the graph certi cate construction algorithm can nontrivially im- pact the walk's distinguishing power. We also show that no continuous-time walk of a xed number of particles can distinguish all strongly regular graphs when used in conjunction with any of the graph certi cates we consider. We extend this constraint to discrete-time walks of xed numbers of noninteracting particles for one kind of graph certi cate; it remains an open question as to whether or not this constraint applies to the other graph certi cates we consider.« less

  12. Quantum snake walk on graphs

    SciTech Connect

    Rosmanis, Ansis

    2011-02-15

    I introduce a continuous-time quantum walk on graphs called the quantum snake walk, the basis states of which are fixed-length paths (snakes) in the underlying graph. First, I analyze the quantum snake walk on the line, and I show that, even though most states stay localized throughout the evolution, there are specific states that most likely move on the line as wave packets with momentum inversely proportional to the length of the snake. Next, I discuss how an algorithm based on the quantum snake walk might potentially be able to solve an extended version of the glued trees problem, which asks to find a path connecting both roots of the glued trees graph. To the best of my knowledge, no efficient quantum algorithm solving this problem is known yet.

  13. Base Station Walk-Back

    NASA Video Gallery

    Train to improve your lung, heart, and other muscle endurance while walking a progressive, measured distance. The Train Like an Astronaut project uses the excitement of exploration to challenge stu...

  14. Walking Robot Locomotion System Conception

    NASA Astrophysics Data System (ADS)

    Ignatova, D.; Abadjieva, E.; Abadjiev, V.; Vatzkitchev, Al.

    2014-09-01

    This work is a brief analysis on the application and perspective of using the walking robots in different areas in practice. The most common characteristics of walking four legs robots are presented here. The specific features of the applied actuators in walking mechanisms are also shown in the article. The experience of Institute of Mechanics - BAS is illustrated in creation of Spiroid and Helicon1 gears and their assembly in actuation of studied robots. Loading on joints reductors of robot legs is modelled, when the geometrical and the walking parameters of the studied robot are preliminary defined. The obtained results are purposed for designing the control of the loading of reductor type Helicon in the legs of the robot, when it is experimentally tested.

  15. Walking Safely in Rural Areas

    MedlinePlus

    ... provide uneven footing. Often the vehicles on rural roads travel at much higher speeds than walkers are ... walking on or near the side of the road. Go4Life has the following safety tips for those ...

  16. Walking and jumping spores

    NASA Astrophysics Data System (ADS)

    Marmottant, Philippe

    2012-02-01

    The Equisetum plants, more commonly called ``horsetail,'' emit 50-microns spores that are spherical in shape and present four hygroscopic arms. Under high humidity, the arms are retracted. But under lower humidity, less than 70%, the four arms deploy beautifully. With time-lapse image recordings, we show that under repeated cycles of dry and high humidity, the spores behave as random walkers, since they move by about their size in a different direction at every cycle. The process is apparently stochastic because of the complex shape of the arms and hysteretic friction of the arms on the ground. For some spores, a decrease in humidity level results in very fast jumps, the spores taking off at a typical velocity of a meter per second, as recorded on high-speed camera. With these jumps, they reach centimetric elevations, much larger than their size. The physical mechanism at the root of these ``Levy-flight'' jumps is still under investigation. The walking and jumping phenomena thus provide motility, which we believe is helpful for the understanding of the biological dispersion of the spores. It could also bring biomimetic inspiration to engineer new motile elastic structures.

  17. Quantum walk with jumps

    NASA Astrophysics Data System (ADS)

    Lavička, H.; Potoček, V.; Kiss, T.; Lutz, E.; Jex, I.

    2011-09-01

    We analyze a special class of 1-D quantum walks (QWs) realized using optical multi-ports. We assume non-perfect multi-ports showing errors in the connectivity, i.e. with a small probability the multi-ports can connect not to their nearest neighbor but to another multi-port at a fixed distance - we call this a jump. We study two cases of QW with jumps where multiple displacements can emerge at one timestep. The first case assumes time-correlated jumps (static disorder). In the second case, we choose the positions of jumps randomly in time (dynamic disorder). The probability distributions of position of the QW walker in both instances differ significantly: dynamic disorder leads to a Gaussian-like distribution, while for static disorder we find two distinct behaviors depending on the parity of jump size. In the case of even-sized jumps, the distribution exhibits a three-peak profile around the position of the initial excitation, whereas the probability distribution in the odd case follows a Laplace-like discrete distribution modulated by additional (exponential) peaks for long times. Finally, our numerical results indicate that by an appropriate mapping a universal functional behavior of the variance of the long-time probability distribution can be revealed with respect to the scaled average of jump size.

  18. Superpersistent currents and whispering gallery modes in relativistic quantum chaotic systems.

    PubMed

    Xu, Hongya; Huang, Liang; Lai, Ying-Cheng; Grebogi, Celso

    2015-01-01

    Persistent currents (PCs), one of the most intriguing manifestations of the Aharonov-Bohm (AB) effect, are known to vanish for Schrödinger particles in the presence of random scatterings, e.g., due to classical chaos. But would this still be the case for Dirac fermions? Addressing this question is of significant value due to the tremendous recent interest in two-dimensional Dirac materials. We investigate relativistic quantum AB rings threaded by a magnetic flux and find that PCs are extremely robust. Even for highly asymmetric rings that host fully developed classical chaos, the amplitudes of PCs are of the same order of magnitude as those for integrable rings, henceforth the term superpersistent currents (SPCs). A striking finding is that the SPCs can be attributed to a robust type of relativistic quantum states, i.e., Dirac whispering gallery modes (WGMs) that carry large angular momenta and travel along the boundaries. We propose an experimental scheme using topological insulators to observe and characterize Dirac WGMs and SPCs, and speculate that these features can potentially be the base for a new class of relativistic qubit systems. Our discovery of WGMs in relativistic quantum systems is remarkable because, although WGMs are common in photonic systems, they are relatively rare in electronic systems. PMID:25758591

  19. Superpersistent currents and whispering gallery modes in relativistic quantum chaotic systems

    PubMed Central

    Xu, Hongya; Huang, Liang; Lai, Ying-Cheng; Grebogi, Celso

    2015-01-01

    Persistent currents (PCs), one of the most intriguing manifestations of the Aharonov-Bohm (AB) effect, are known to vanish for Schrödinger particles in the presence of random scatterings, e.g., due to classical chaos. But would this still be the case for Dirac fermions? Addressing this question is of significant value due to the tremendous recent interest in two-dimensional Dirac materials. We investigate relativistic quantum AB rings threaded by a magnetic flux and find that PCs are extremely robust. Even for highly asymmetric rings that host fully developed classical chaos, the amplitudes of PCs are of the same order of magnitude as those for integrable rings, henceforth the term superpersistent currents (SPCs). A striking finding is that the SPCs can be attributed to a robust type of relativistic quantum states, i.e., Dirac whispering gallery modes (WGMs) that carry large angular momenta and travel along the boundaries. We propose an experimental scheme using topological insulators to observe and characterize Dirac WGMs and SPCs, and speculate that these features can potentially be the base for a new class of relativistic qubit systems. Our discovery of WGMs in relativistic quantum systems is remarkable because, although WGMs are common in photonic systems, they are relatively rare in electronic systems. PMID:25758591

  20. Human Genome Program Image Gallery (from genomics.energy.gov)

    DOE Data Explorer

    This collection contains approximately 240 images from the genome programs of DOE's Office of Science. The images are divided into galleries related to biofuels research, systems biology, and basic genomics. Each image has a title, a basic citation, and a credit or source. Most of the images are original graphics created by the Genome Management Information System (GMIS). GMIS images are recognizable by their credit line. Permission to use these graphics is not needed, but please credit the U.S. Department of Energy Genome Programs and provide the website http://genomics.energy.gov. Other images were provided by third parties and not created by the U.S. Department of Energy. Users must contact the person listed in the credit line before using those images. The high-resolution images can be downloaded.

  1. Dispersion analysis of whispering gallery mode microbubble resonators.

    PubMed

    Riesen, Nicolas; Zhang, Wen Qi; Monro, Tanya M

    2016-04-18

    This paper examines the opportunities existing for engineering dispersion in non-silica whispering gallery mode microbubble resonators, for applications such as optical frequency comb generation. More specifically, the zero dispersion wavelength is analyzed as a function of microbubble diameter and wall thickness for several different material groups such as highly-nonlinear soft glasses, polymers and crystalline materials. The zero dispersion wavelength is shown to be highly-tunable by changing the thickness of the shell. Using certain materials it is shown that dispersion equalization can be realized at interesting wavelengths such as deep within the visible or mid-infrared, opening up new possibilities for optical frequency comb generation. This study represents the first extensive analysis of the prospects of using non-silica microbubbles for nonlinear optics. PMID:27137317

  2. Elementary modes of coupled oscillators as whispering-gallery microresonators

    NASA Astrophysics Data System (ADS)

    Banerjee, Rabin; Mukherjee, Pradip

    2015-10-01

    We obtain the elementary modes of a system of parity-time reversal (PT)-symmetric coupled oscillators with balanced loss and gain. These modes are used to give a physical picture of the phase transition recently reported [C. M. Bender, M. Gianfreda, B. Peng, S. K. Özdemir and L. Yang, Phys. Rev. A 88, 062111 (2013); L. Yang, S. K. Özdemir and B. Peng, 12th Int. Workshop and Conf. Pseudo-Hermitian Hamiltonians in Quantum Physics, Istanbul, Turkey, July 2013; B. Peng, S. K. Özdemir, F. Lei, F. Monifi, M. Gianfreda, G. L. Long, S. Fan, F. Nori, C. M. Bender and L. Yang, Nat. Phys. 10, 394 (2014)] in experiments with whispering-gallery microresonators.

  3. All-polymer whispering gallery mode sensor system.

    PubMed

    Petermann, Ann Britt; Varkentin, Arthur; Roth, Bernhard; Morgner, Uwe; Meinhardt-Wollweber, Merve

    2016-03-21

    Sensors based on whispering gallery modes have been extensively investigated with respect to their possible application as physical or biological sensors. Instead of using a single resonator, we use an all polymer resonator array as sensing element. A tunable narrowband laser is coupled into a PMMA plate serving as an optical wave guide. PMMA spheres are placed in the evanescent field on the surface of the plate. Due to small size variations, some spheres are in resonance at a given wavelength while others are not. We show that this device is well suited for the determination of an unknown wavelength or for temperature measurements. Moreover, we discuss several general aspects of the sensor concept such as the number and size of sensing elements which are necessary for a correct measurement result, or the maximum acceptable linewidth of the laser. PMID:27136799

  4. Genome Structure Gallery from the Mycobacterium Tuberculosis Structual Genomics Consortium

    DOE Data Explorer

    The TB Structural Genomics Consortium works with the structures of proteins from M. tuberculosis, analyzing these structures in the context of functional information that currently exists and that the Consortium generates. The database of linked structural and functional information constructed from this project will form a lasting basis for understanding M. tuberculosis pathogenesis and for structure-based drug design. The Consortium's structural and functional information is publicly available. The Structures Gallery makes more than 650 total structures available by PDB identifier. Some of these are not consortium targets, but all are viewable in 3D color and can be manipulated in various ways by Jmol, an open-source Java viewer for chemical structures in 3D from http://www.jmol.org/

  5. A temperature sensor based on a whispering gallery mode resonator

    NASA Astrophysics Data System (ADS)

    Yu, L.; Fernicola, V.

    2013-09-01

    This paper deals with a microwave temperature sensor based on a whispering gallery mode (WGM) resonator whose dielectric medium is a cylindrical sapphire crystal. The performance as temperature sensor were investigated a three WGMs resonant frequencies over the temperature range from -40 °C to 85 °C. It was found that the quality factor for these WGMs can be in excess of 1.7ṡ105, potentially enabling high-resolution measurements. The temperature repeatability, stability, hysteresis, frequency-vs-temperature sensitivity of the WGM temperature sensor are reported. Moreover, two sapphires, which have the same nominal characteristics, were investigated in order to assess the system reproducibility and the results reported.

  6. Spherical-sapphire-based whispering gallery mode resonator thermometer

    NASA Astrophysics Data System (ADS)

    Yu, Lili; Fernicola, V.

    2012-09-01

    A novel microwave whispering gallery mode (WGM) resonator based on a spherical sapphire crystal was developed at INRIM and its use as a thermometer was tested. The temperature dependence of the WGM frequencies was studied and the most promising resonance near to 13.6 GHz, with a loaded quality factor as large as 82 000, was carefully investigated. Its potential use in thermometry was evaluated through a study of its main metrological characteristics, such as the temperature sensitivity, the frequency stability, the repeatability, and the resolution at several temperatures over the temperature range -40 °C to 85 °C. Finally, the INRIM spherical sapphire thermometer was compared with the NIST SWGT, a dielectric thermometer based on a cylindrical sapphire resonator [V. B. Braginsky, V. S. Ilchenko, and Kh. S. Bagdassarov, Phys. Lett. A 120(3), 300 (1987), 10.1016/0375-9601(87)90676-1].

  7. Spherical-sapphire-based whispering gallery mode resonator thermometer.

    PubMed

    Yu, Lili; Fernicola, V

    2012-09-01

    A novel microwave whispering gallery mode (WGM) resonator based on a spherical sapphire crystal was developed at INRIM and its use as a thermometer was tested. The temperature dependence of the WGM frequencies was studied and the most promising resonance near to 13.6 GHz, with a loaded quality factor as large as 82 000, was carefully investigated. Its potential use in thermometry was evaluated through a study of its main metrological characteristics, such as the temperature sensitivity, the frequency stability, the repeatability, and the resolution at several temperatures over the temperature range -40 °C to 85 °C. Finally, the INRIM spherical sapphire thermometer was compared with the NIST SWGT, a dielectric thermometer based on a cylindrical sapphire resonator [V. B. Braginsky, V. S. Ilchenko, and Kh. S. Bagdassarov, Phys. Lett. A 120(3), 300 (1987)]. PMID:23020404

  8. Method for predicting whispering gallery mode spectra of spherical microresonators.

    PubMed

    Hall, Jonathan M M; Afshar V, Shahraam; Henderson, Matthew R; François, Alexandre; Reynolds, Tess; Riesen, Nicolas; Monro, Tanya M

    2015-04-20

    A full three-dimensional Finite-Difference Time-Domain (FDTD)-based toolkit is developed to simulate the whispering gallery modes of a microsphere in the vicinity of a dipole source. This provides a guide for experiments that rely on efficient coupling to the modes of microspheres. The resultant spectra are compared to those of analytic models used in the field. In contrast to the analytic models, the FDTD method is able to collect flux from a variety of possible collection regions, such as a disk-shaped region. The customizability of the technique allows one to consider a variety of mode excitation scenarios, which are particularly useful for investigating novel properties of optical resonators, and are valuable in assessing the viability of a resonator for biosensing. PMID:25969034

  9. Tuning whispering gallery modes using internal aerostatic pressure.

    PubMed

    Henze, Rico; Seifert, Tom; Ward, Jonathan; Benson, Oliver

    2011-12-01

    Aerostatic tuning of whispering gallery modes (WGMs) in a microbubble resonator is demonstrated. The optical modes are redshifted over hundreds of gigahertz (GHz) simply by increasing the air pressure (up to 6 bars) inside the microbubble. A description of the pressure tuning properties of the WGMs in microbubbles is given in terms of the corresponding elasto-optical equations of spherical shells and the results are compared to experimental data. Microbubbles as small as 74 μm are tested and the experimental results show excellent agreement with the theory. An estimation method is developed for calculating the wall thicknesses of the microbubbles from the diameters, which are measured via direct microscopy. A geometrical factor χ is defined and a linear relationship between the shift rate (GHz/bar) of the bubbles modes and χ is observed. PMID:22139234

  10. Brillouin lasing in whispering gallery micro-resonators

    NASA Astrophysics Data System (ADS)

    Sturman, B.; Breunig, I.

    2015-12-01

    Thresholds of stimulated Brillouin scattering (SBS) in solid-state whispering gallery mode (WGM) microresonators are analyzed. It is shown that the SBS interaction is substantially different here from that known in the bulk case and in the case of water droplet resonators. The reason is the absence of pure longitudinal acoustic WGMs owing to strong coupling of the longitudinal (l) and transverse (t) acoustic displacements at the surface of the resonator. As a result, a considerable increase of the SBS thresholds takes place, and the lowest thresholds correspond to the hybrid tl-modes with very large radial indices. Nevertheless, the thresholds lie in the μW range of the pump power. Dependence of the SBS power thresholds on the modal numbers and the possibility of self-tuning to the SBS resonance are analyzed.

  11. Portable walking beam pump jack

    SciTech Connect

    Laney, R.N.

    1986-02-25

    This patent describes a portable walking beam pump jack for use in pumping liquids from an oil well. This jack consists of: an elongated frame having a longitudinal axis and front and rear ends, the frame also including first and second support seats; a towing receptacle, an axle connected transversely across the frame; ground engaging wheels connected to the axle for supporting the frame for rolling transportation; stabilizing means for securing the frame with respect to a ground location; a walking beam having a first end, a midportion and a second end, the second end being adapted for connection to a pumping rod; an engine mounted on the frame; a pair of arms counterweighted for balancing a pumping rod connected to the walking beam, a drive yoke, a support assembly foldably mounted on the frame and upon which the midportion of the walking beam is pivotally connected, the support assembly the arms and the drive yoke being foldable together, from a first, fixed position in which the walking beam arms and yoke are supported in a raised position for rocking in a pumping motion to a second, fixed position disposed downwardly and forwardly from the first fixed position and in which the walking beam arms and yoke are held in a lowered position for transportation; a front support and a hydraulic cylinder connected between the frame and the support assembly for moving the support assembly between the first, fixed position and the second fixed position.

  12. Microwave Photonics Systems Based on Whispering-gallery-mode Resonators

    PubMed Central

    Coillet, Aurélien; Henriet, Rémi; Phan Huy, Kien; Jacquot, Maxime; Furfaro, Luca; Balakireva, Irina; Larger, Laurent; Chembo, Yanne K.

    2013-01-01

    Microwave photonics systems rely fundamentally on the interaction between microwave and optical signals. These systems are extremely promising for various areas of technology and applied science, such as aerospace and communication engineering, sensing, metrology, nonlinear photonics, and quantum optics. In this article, we present the principal techniques used in our lab to build microwave photonics systems based on ultra-high Q whispering gallery mode resonators. First detailed in this article is the protocol for resonator polishing, which is based on a grind-and-polish technique close to the ones used to polish optical components such as lenses or telescope mirrors. Then, a white light interferometric profilometer measures surface roughness, which is a key parameter to characterize the quality of the polishing. In order to launch light in the resonator, a tapered silica fiber with diameter in the micrometer range is used. To reach such small diameters, we adopt the "flame-brushing" technique, using simultaneously computer-controlled motors to pull the fiber apart, and a blowtorch to heat the fiber area to be tapered. The resonator and the tapered fiber are later approached to one another to visualize the resonance signal of the whispering gallery modes using a wavelength-scanning laser. By increasing the optical power in the resonator, nonlinear phenomena are triggered until the formation of a Kerr optical frequency comb is observed with a spectrum made of equidistant spectral lines. These Kerr comb spectra have exceptional characteristics that are suitable for several applications in science and technology. We consider the application related to ultra-stable microwave frequency synthesis and demonstrate the generation of a Kerr comb with GHz intermodal frequency. PMID:23963358

  13. Microwave photonics systems based on whispering-gallery-mode resonators.

    PubMed

    Coillet, Aurélien; Henriet, Rémi; Phan Huy, Kien; Jacquot, Maxime; Furfaro, Luca; Balakireva, Irina; Larger, Laurent; Chembo, Yanne K

    2013-01-01

    Microwave photonics systems rely fundamentally on the interaction between microwave and optical signals. These systems are extremely promising for various areas of technology and applied science, such as aerospace and communication engineering, sensing, metrology, nonlinear photonics, and quantum optics. In this article, we present the principal techniques used in our lab to build microwave photonics systems based on ultra-high Q whispering gallery mode resonators. First detailed in this article is the protocol for resonator polishing, which is based on a grind-and-polish technique close to the ones used to polish optical components such as lenses or telescope mirrors. Then, a white light interferometric profilometer measures surface roughness, which is a key parameter to characterize the quality of the polishing. In order to launch light in the resonator, a tapered silica fiber with diameter in the micrometer range is used. To reach such small diameters, we adopt the "flame-brushing" technique, using simultaneously computer-controlled motors to pull the fiber apart, and a blowtorch to heat the fiber area to be tapered. The resonator and the tapered fiber are later approached to one another to visualize the resonance signal of the whispering gallery modes using a wavelength-scanning laser. By increasing the optical power in the resonator, nonlinear phenomena are triggered until the formation of a Kerr optical frequency comb is observed with a spectrum made of equidistant spectral lines. These Kerr comb spectra have exceptional characteristics that are suitable for several applications in science and technology. We consider the application related to ultra-stable microwave frequency synthesis and demonstrate the generation of a Kerr comb with GHz intermodal frequency. PMID:23963358

  14. Rarefying Spectra of Whispering-Gallery-Mode Resonators

    NASA Technical Reports Server (NTRS)

    Savchenkov, Anatoliy; Matsko, Andrey; Strekalov, Dmitri; Iltchenko, Vladimir; Maleki, Lute

    2007-01-01

    A method of cleaning the mode spectra of whispering-gallery-mode (WGM) optical resonators has been devised to make such resonators more suitable for use as narrow-band optical filters. The method applies, more specifically, to millimeter- sized whispering-gallery-mode optical resonators that are made of crystalline electro-optical materials and have ultrahigh values of the resonance quality factor (Q). The mode spectrum of such a resonator is typically dense, consisting of closely spaced families of modes; as such, the spectrum is not well suited for narrow-band filtering, in which there is a need for strong rejection of side modes. Cleaning as used here signifies rarefying the spectrum so that what remains consists mostly of a single desired family of modes or, at worst, a few mode families that are more widely spaced in frequency than are the mode families in the original, non-rarefied spectrum. The spectrum-cleaning method exploits the fact that various WGM mode families occupy various positions near the equator at the rim of a resonator disk. In this method, a damper in the form of a prism or other polished piece of material having an index of refraction greater than that of the resonator material is placed in contact with the rim of the resonator at such a position that the Qs of most or all of the undesired mode families are greatly reduced while the Q of the desired mode family is reduced by only a tolerably small amount. In an alternative method that has been considered, the mode spectrum would be cleaned through special design of the shape of the rim, but fabrication of the rim in a special shape is a complicated task. The advantage of the present method, relative to the alternative method, is that special shaping of the rim is not necessary and the damping prism can be emplaced after the resonator has been fabricated.

  15. The Cosmology Gallery: Unity through diversity in a vast and awe-inspiring universe.

    NASA Astrophysics Data System (ADS)

    Goldsmith, John

    2011-06-01

    Scientists, artists, religious and cultural leaders have come together to create the Cosmology Gallery at the Gravity Discovery Centre (GDC) located 70 km north of Perth, Western Australia. The Cosmology Gallery exhibitions include the multicultural cosmology artworks, Celestial Visions astronomical photography exhibition and the Timeline of the Universe. The multicultural cosmology artworks are new artworks inspired by Australian Indigenous, Christian, Buddhist, Islamic, Hindu, scientific and technological perspectives of the universe. The Celestial Visions exhibition features astronomical events above famous landmarks, including Stonehenge and the Pyramids. The AUD 400,000+ project was funded by Lotterywest, Western Australia and the Cosmology Gallery was officially opened in July 2008 by the Premier of Western Australia.

  16. 10 CFR 431.302 - Definitions concerning walk-in coolers and walk-in freezers.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... cooler or walk-in freezer that are not part of its refrigeration system. K-factor means the thermal conductivity of a material. Manufacturer of a walk-in cooler or walk-in freezer means any person who:...

  17. 10 CFR 431.302 - Definitions concerning walk-in coolers and walk-in freezers.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... cooler or walk-in freezer that are not part of its refrigeration system. K-factor means the thermal conductivity of a material. Manufacturer of a walk-in cooler or walk-in freezer means any person who:...

  18. 10 CFR 431.302 - Definitions concerning walk-in coolers and walk-in freezers.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... cooler or walk-in freezer that are not part of its refrigeration system. K-factor means the thermal conductivity of a material. Manufacturer of a walk-in cooler or walk-in freezer means any person who:...

  19. Unitary equivalent classes of one-dimensional quantum walks

    NASA Astrophysics Data System (ADS)

    Ohno, Hiromichi

    2016-06-01

    This study investigates unitary equivalent classes of one-dimensional quantum walks. We prove that one-dimensional quantum walks are unitary equivalent to quantum walks of Ambainis type and that translation-invariant one-dimensional quantum walks are Szegedy walks. We also present a necessary and sufficient condition for a one-dimensional quantum walk to be a Szegedy walk.

  20. Posing Einstein's Question: Questioning Einstein's Pose.

    ERIC Educational Resources Information Center

    Topper, David; Vincent, Dwight E.

    2000-01-01

    Discusses the events surrounding a famous picture of Albert Einstein in which he poses near a blackboard containing a tensor form of his 10 field equations for pure gravity with a question mark after it. Speculates as to the content of Einstein's lecture and the questions he might have had about the equation. (Contains over 30 references.) (WRM)

  1. Tunable Optical Filters Having Electro-optic Whispering-gallery-mode Resonators

    NASA Technical Reports Server (NTRS)

    Savchenkov, Anatoliy (Inventor); Ilchenko, Vladimir (Inventor); Matsko, Andrey B. (Inventor); Maleki, Lutfollah (Inventor)

    2006-01-01

    Tunable optical filters using whispering-gallery-mode (WGM) optical resonators are described. The WGM optical resonator in a filter exhibits an electro-optical effect and hence is tunable by applying a control electrical signal.

  2. Interior hallway, at 1250 Gallery, showing entrance into PumpGenerating Plant ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior hallway, at 1250 Gallery, showing entrance into Pump-Generating Plant from Left Powerhouse, looking southwest. - Columbia Basin Project, Grand Coulee Dam Powerplant Complex, Grand Coulee, Grant County, WA

  3. OPTICAL SOLITONS: Optical solitons appearing during propagation of whispering-gallery waves

    NASA Astrophysics Data System (ADS)

    Torchigin, V. P.; Torchigin, S. V.

    2003-10-01

    The properties of solitons appearing during the propagation of whispering-gallery waves in a homogeneous glass cylinder are considered. It is shown that such solitons can be used for the light frequency conversion.

  4. The Junior Gallery: A Hands-On Space for Learning and Creating.

    ERIC Educational Resources Information Center

    Podhurst, Jamie

    2001-01-01

    Describes an educational program focusing on workshops at the Junior Gallery, a part of the Everhart Museum (Scranton, Pennsylvania). Explains that the museum's collection is integrated with lessons in art appreciation, production, natural history, and other subject areas. (CMK)

  5. 6. TROLLEY WASHER/OILER IN SOUTHWEST CORNER OF GALLERY LEVEL; LOOKING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. TROLLEY WASHER/OILER IN SOUTHWEST CORNER OF GALLERY LEVEL; LOOKING NORTHEAST - Rath Packing Company, Beef Killing Building, Sycamore Street between Elm & Eighteenth Streets, Waterloo, Black Hawk County, IA

  6. 75 FR 15740 - Gallery Leather Company, Inc., Trenton, ME; Notice of Termination of Investigation

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-30

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF LABOR Employment and Training Administration Gallery Leather Company, Inc., Trenton, ME; Notice of Termination of... Leather Company, Inc., Trenton, Maine. The petitioner has requested that the petition be...

  7. Direct electrical-to-optical conversion and light modulation in micro whispering-gallery-mode resonators

    NASA Technical Reports Server (NTRS)

    Maleki, Lute (Inventor); Levi, Anthony F. J. (Inventor)

    2005-01-01

    Techniques for directly converting an electrical signal into an optical signal by using a whispering gallery mode optical resonator formed of a dielectric material that allows for direct modulation of optical absorption by the electrical signal.

  8. Three-dimensional whispering gallery modes in InGaAs nanoneedle lasers on silicon

    SciTech Connect

    Tran, T.-T. D.; Chen, R.; Ng, K. W.; Ko, W. S.; Lu, F.; Chang-Hasnain, C. J.

    2014-09-15

    As-grown InGaAs nanoneedle lasers, synthesized at complementary metal–oxide–semiconductor compatible temperatures on polycrystalline and crystalline silicon substrates, were studied in photoluminescence experiments. Radiation patterns of three-dimensional whispering gallery modes were observed upon optically pumping the needles above the lasing threshold. Using the radiation patterns as well as finite-difference-time-domain simulations and polarization measurements, all modal numbers of the three-dimensional whispering gallery modes could be identified.

  9. Any Questions, Please?

    ERIC Educational Resources Information Center

    Pollio, Howard R.

    1989-01-01

    This pamphlet discusses the use of questioning in the college classroom and its contribution to learning. Starting with a brief examination of the ways children question, discussions cover: (1) the effects of linguistic and socio-linguistic characteristics in questioning; (2) questions in psychotherapy, law, and opinion polling; (3) classroom…

  10. GPR investigations in galleries buried inside a karstified limestone formation

    NASA Astrophysics Data System (ADS)

    Rousset, D.; Sénéchal, G.; Gaffet, S.

    2009-04-01

    A large scientific program of geophysical investigations is presently performed inside the Low-Noise Underground Laboratory (Laboratoire Souterrain à Bas Bruit / LSBB, Rustrel, France) which is an decomissioned underground missile control center, buried in a karstified limestone formation. One of the goals of this project is the understanding of the water circulation inside the structure. This experimental site offers a unique opportunity of perfoming measurements within an unweathered limestone massif. The tunnel has been dug in lower cretaceous limestone which is characterized by a low clay content, high electrical resistivity. The dip is around 25 degrees and vertical faults locally affect the structure. The studied zone is located in south-eastern France (Provence) and is characterized by a mediterranean climate with long dry periods and strong, short events of rain. This phenomenon induces large variations of water content within the karstified limestone from dry to saturated conditions. Analysis of the spatial and temporal variations of the water flow in a karstified limestones needs to define the geological context and the adequate geophysical methods. GPR offers a good tradeoff between resolution and ease of use on one hand and investigation depth on the other hand. We present some GPR profiles which have been acquired in April 2008 after a quite long and strong period of rain, inducing a complete water saturation inside the karstified massif. We used several RAMAC shielded antennas from 100 to 500 MHz. The longest profile is around 600 m long, with a 20 cm spacing, running from a raw to a concrete gallery. These data sets are characterized by a very good signal to noise ratio and a signal penetration, up to 18 meters. Signal processing includes very low frequency filtering, amplitude compensation, keeping lateral relative attenuation and ringing suppression. Final sections includes migration and time to depth conversion or depth migration. The estimated

  11. Genome walking by Klenow polymerase.

    PubMed

    Volpicella, Mariateresa; Leoni, Claudia; Fanizza, Immacolata; Rius, Sebastian; Gallerani, Raffaele; Ceci, Luigi R

    2012-11-15

    Genome walking procedures are all based on a final polymerase chain reaction amplification, regardless of the strategy employed for the synthesis of the substrate molecule. Here we report a modification of an already established genome walking strategy in which a single-strand DNA substrate is obtained by primer extension driven by Klenow polymerase and which results suitable for the direct sequencing of complex eukaryotic genomes. The efficacy of the method is demonstrated by the identification of nucleotide sequences in the case of two gene families (chiA and P1) in the genomes of several maize species. PMID:22922302

  12. Driven discrete time quantum walks

    NASA Astrophysics Data System (ADS)

    Hamilton, Craig S.; Barkhofen, Sonja; Sansoni, Linda; Jex, Igor; Silberhorn, Christine

    2016-07-01

    We introduce the driven discrete time quantum walk (QW), where walkers are added during the walk instead of only at the beginning. This leads to interference in walker number and very different dynamics when compared to the original QW. These dynamics have two regimes, which we illustrate using the one-dimensional line. Then, we explore a search application which has certain advantages over current search protocols, namely that it does not require a complicated initial state nor a specific measurement time to observe the marked state. Finally, we describe a potential experimental implementation using existing technology.

  13. Measuring victimization inside prisons: questioning the questions.

    PubMed

    Wolff, Nancy; Jing Shi; Bachman, Ronet

    2008-10-01

    Violence and victimization inside the prison setting are accepted as facts, although the facts about their prevalence remain uncertain. Variation in the methods used to estimate rates of sexual and physical victimization contribute to the wide range in estimates appearing in the prison literature. This article focuses on the questions used in the prison victimization literature to elicit information on victimization from inmates, compared to questions used in the general victimization literature. The questions used in the National Violence Against Women and Men Surveys are used to estimate sexual and physical victimization rates for an entire prison system. Rates of victimization were found to vary significantly by specificity of the question, definition of perpetrator, and clustering of behaviors. Facts about victimization inside prison will become more certain when the methodology becomes more standardized and consistent with definitions of victimization. PMID:18309042

  14. After Talking the Talk, Now Walk the Walk

    ERIC Educational Resources Information Center

    Vukovic, Paul

    2011-01-01

    In this article, the author describes what his students are doing following the ATM Easter conference in Telford, where he was inspired by a workshop entitled "Vitamin D Maths," conducted by Jocelyn D'Arcy. He describes an activity that allows his Year 11 students to walk through angles drawn on the floors. This topic will now literally be given a…

  15. High-Q BBO whispering gallery mode resonators

    NASA Astrophysics Data System (ADS)

    Lin, Guoping; Fürst, Josef U.; Strekalov, Dmitry V.; Grudinin, Ivan S.; Yu, Nan

    2013-02-01

    We report an investigation on optical whispering gallery mode (WGM) resonators made from non z-cut beta barium borate (BBO) crystals. We first fabricated high quality (Q) factor WGM resonators made of an angle-cut BBO crystal. Q factors of 1×108 level have been demonstrated at various wavelengths including UV. They led to new upper bounds for the absorption coefficients of BBO at 1560 nm, 980 nm and 370 nm. We observed only one set of ordinarily polarized WGMs with polarization rotating along the resonator circumference. We also fabricated xy-cut BBO WGM resonators, in which the optic axis is parallel to the resonator plane. In that case, two WGM families with different polarization exist, one with constant the other with oscillatory phase velocity. This enables a novel way of broadband phase matching in WGM resonators with cyclic gain. We experimentally demonstrated efficient second harmonic generation (SHG) to a wide harmonic wavelength range from 780 nm at near infrared to 317 nm in UV. It is also the first reported direct UV SHG in a high-Q WGM resonator. This work lays a foundation for further investigations of WGM properties of non-z cut birefringent resonators and their applications in nonlinear optics.

  16. Protein-based flexible whispering gallery mode resonators

    NASA Astrophysics Data System (ADS)

    Yilmaz, Huzeyfe; Pena-Francesch, Abdon; Xu, Linhua; Shreiner, Robert; Jung, Huihun; Huang, Steven H.; Özdemir, Sahin K.; Demirel, Melik C.; Yang, Lan

    2016-02-01

    The idea of creating photonics tools for sensing, imaging and material characterization has long been pursued and many achievements have been made. Approaching the level of solutions provided by nature however is hindered by routine choice of materials. To this end recent years have witnessed a great effort to engineer mechanically flexible photonic devices using polymer substrates. On the other hand, biodegradability and biocompatibility still remains to be incorporated. Hence biomimetics holds the key to overcome the limitations of traditional materials in photonics design. Natural proteins such as sucker ring teeth (SRT) and silk for instance have remarkable mechanical and optical properties that exceed the endeavors of most synthetic and natural polymers. Here we demonstrate for the first time, toroidal whispering gallery mode resonators (WGMR) fabricated entirely from protein structures such as SRT of Loligo vulgaris (European squid) and silk from Bombyx mori. We provide here complete optical and material characterization of proteinaceous WGMRs, revealing high quality factors in microscale and enhancement of Raman signatures by a microcavity. We also present a most simple application of a WGMR as a natural protein add-drop filter, made of SRT protein. Our work shows that with protein-based materials, optical, mechanical and thermal properties can be devised at the molecular level and it lays the groundwork for future eco-friendly, flexible photonics device design.

  17. Optothermal transport behavior in whispering gallery mode optical cavities

    NASA Astrophysics Data System (ADS)

    Soltani, Soheil; M. Armani, Andrea

    2014-08-01

    Over the past century, whispering gallery mode optical cavities have enabled numerous advances in science and engineering, such as discoveries in quantum mechanics and non-linear optics, as well as the development of optical gyroscopes and add drop filters. One reason for their widespread appeal is their ability to confine light for long periods of time, resulting in high circulating intensities. However, when sufficiently large amounts of optical power are coupled into these cavities, they begin to experience optothermal or photothermal behavior, in which the optical energy is converted into heat. Above the optothermal threshold, the resonance behavior is no longer solely defined by electromagnetics. Previous work has primarily focused on the role of the optothermal coefficient of the material in this instability. However, the physics of this optothermal behavior is significantly more complex. In the present work, we develop a predictive theory based on a generalizable analytical expression in combination with a geometry-specific COMSOL Multiphysics finite element method model. The simulation couples the optical and thermal physics components, accounting for geometry variations as well as the temporal and spatial profile of the optical field. To experimentally verify our theoretical model, the optothermal thresholds of a series of silica toroidal resonant cavities are characterized at different wavelengths (visible through near-infrared) and using different device geometries. The silica toroid offers a particularly rigorous case study for the developed optothermal model because of its complex geometrical structure which provides multiple thermal transport paths.

  18. Dispersion and polarization conversion of whispering gallery modes in nanowires

    SciTech Connect

    Pavlovic, G.; Malpuech, G.; Gippius, N. A.

    2010-11-15

    We investigate theoretically the optical properties of nano-wires (NWs) with cross sections having either discrete or cylindrical symmetry. The material forming the wire is birefringent, showing a different dielectric response in the plane and along the axis of the wire, which is typically the case for wires made of wurtzite materials, such as ZnO or GaN. We look for solutions of Maxwell's equations having the proper symmetry. The dispersions and the linewidths versus angle of incident light for the modes having high momentum in the cross-section plane, so called whispering gallery modes, are calculated. We put a special emphasis on the case of hexagonal cross sections. The energy positions of the modes for a set of azimuthal quantum numbers are shown. We demonstrate the dependence of the energy splitting between TE and TM modes versus birefringence. The polarization conversion from TE to TM with increase in the axial wave vector is discussed for both cylindrical and discrete symmetries.

  19. Phase-Array Approach to Optical Whispering Gallery Modulators

    NASA Technical Reports Server (NTRS)

    Strekalov, Dmitry

    2010-01-01

    This technology leverages the well-defined orbital number of a whispering gallery modulator (WGM) to expand the range of applications for such resonators. This property rigidly connects the phase variation of the field in this mode with the azimuthal angle between the coupling locations. A WGM with orbital momentum L has exactly L instant nodes around the circumference of the WGM resonator supporting such a mode. Therefore, in two locations separated by the arc alpha, the phase difference of such a field will be equal to phi= alpha L. Coupling the field out of such locations, and into a balanced interferometer, once can observe a complete constructive or distractive interference (or have any situation in between) depending on the angle alpha. Similarly, a mode L + delta L will pick up the phase phi + alpha delta L. In all applications of a WGM resonator as a modulator, the orbital numbers for the carrier and sidebands are different, and their differences delta L are known (usually, but not necessarily, delta L = 1). Therefore, the choice of the angle alpha, and of the interferometer arms difference, allows one to control the relative phase between different modes and to perform the conversion, separation, and filtering tasks necessary.

  20. Interfacing whispering gallery mode microresonators for environmental biosensing

    NASA Astrophysics Data System (ADS)

    Hunt, Heather K.; Dahmen, Jeremy L.; Soteropulos, Carol E.

    2014-03-01

    Label-free biosensors that combine high sensitivity and high specificity characteristics have shown tremendous potential for applications in medical diagnostics, and have more recently been extended to the food safety and environmental monitoring arenas. A unique type of label-free, optical biosensor, based on Whispering Gallery Mode microresonators, has tremendous potential to revolutionize biodetection due to its extreme sensitivity. The primary limitation of these biosensors, however, is that they require the addition of biorecognition elements to specifically target a biological species of interest. Therefore, the ability to selectively functionalize the microresonator for a specific target molecule, without degrading device performance, is extremely important, and represents the next step in translating these devices from laboratory to field environments. Here, we demonstrate a variety of straightforward bioconjugation strategies that not only impart specificity to optical microresonators, but also allow for the creation of multi-use platforms for complex environments. Of particular interest is the ability to detect harmful bacteria, insects, and fungi in crop and water systems. The resulting surface chemistries are illustrated with XPS, SEM, and fluorescence and optical microscopy, and the device sensitivity is determined via quantitative microcavity analysis. The ability to minimize non-specific adsorption and target unique molecules in complex environments is demonstrated via ellipsometry and in situ device testing. The resulting devices can be recycled several times without loss of sensitivity. By combining these high sensitivity biosensors with appropriate biochemistries, the resulting platforms can be extended to address broader issues in environmental biosensing that directly impact agriculture.

  1. Conceptual Design Report. Footprint Gallery Upgrade - Civil Construction, May 1988

    SciTech Connect

    1988-05-01

    The Footprint Gallery Complex will be enlarged and modified. The basic outline of the project will be to add 68,100 square feet of new construction, remodel 20,600 square feet of existing space, and retire by removal 17 ,500 square feet. The principal items to be addressed are: the creation of larger Main Control Rooms and Central Control Computer Rooms, the replacement of several temporary structures with permanent facilities, the provision for a growth in population of 132 people, and the creation of an intermediate sized meeting/lecture room facility. Disjointed second floor areas will be connected and made accessible to the handicapped, secure and informative viewing for visitors will be provided, and parking will be increased to match the expected growth. The new construction will provide for a more centralized concentration of systems and support personnel of the Fermilab Accelerator Division, reflecting the growth of these organizations during the last 15 years. Experiments, such as the D-Zero detector and antiproton deceleration (E760), have been assigned to the Accelerator Division for support. The associated physicists and experimenters make up the most significant component of the growth in population for which this construction will provide additional space.

  2. Whispering galleries and the control of artificial atoms

    NASA Astrophysics Data System (ADS)

    Forrester, Derek Michael; Kusmartsev, Feodor V.

    2016-04-01

    Quantum computation using artificial-atoms, such as novel superconducting circuits, can be sensitively controlled by external electromagnetic fields. These fields and the self-fields attributable to the coupled artificial-atoms influence the amount of quantum correlation in the system. However, control elements that can operate without complete destruction of the entanglement of the quantum-bits are difficult to engineer. Here we investigate the possibility of using closely-spaced-linear arrays of metallic-elliptical discs as whispering gallery waveguides to control artificial-atoms. The discs confine and guide radiation through the array with small notches etched into their sides that act as scatterers. We focus on π-ring artificial-atoms, which can generate their own spontaneous fluxes. We find that the micro-discs of the waveguides can be excited by terahertz frequency fields to exhibit whispering-modes and that a quantum-phase-gate composed of π-rings can be operated under their influence. Furthermore, we gauge the level of entanglement through the concurrence measure and show that under certain magnetic conditions a series of entanglement sudden-deaths and revivals occur between the two qubits. This is important for understanding the stability and life-time of qubit operations using, for example, a phase gate in a hybrid of quantum technologies composed of control elements and artificial-atoms.

  3. Optothermal transport behavior in whispering gallery mode optical cavities

    SciTech Connect

    Soltani, Soheil; Armani, Andrea M.

    2014-08-04

    Over the past century, whispering gallery mode optical cavities have enabled numerous advances in science and engineering, such as discoveries in quantum mechanics and non-linear optics, as well as the development of optical gyroscopes and add drop filters. One reason for their widespread appeal is their ability to confine light for long periods of time, resulting in high circulating intensities. However, when sufficiently large amounts of optical power are coupled into these cavities, they begin to experience optothermal or photothermal behavior, in which the optical energy is converted into heat. Above the optothermal threshold, the resonance behavior is no longer solely defined by electromagnetics. Previous work has primarily focused on the role of the optothermal coefficient of the material in this instability. However, the physics of this optothermal behavior is significantly more complex. In the present work, we develop a predictive theory based on a generalizable analytical expression in combination with a geometry-specific COMSOL Multiphysics finite element method model. The simulation couples the optical and thermal physics components, accounting for geometry variations as well as the temporal and spatial profile of the optical field. To experimentally verify our theoretical model, the optothermal thresholds of a series of silica toroidal resonant cavities are characterized at different wavelengths (visible through near-infrared) and using different device geometries. The silica toroid offers a particularly rigorous case study for the developed optothermal model because of its complex geometrical structure which provides multiple thermal transport paths.

  4. Whispering galleries and the control of artificial atoms

    PubMed Central

    Forrester, Derek Michael; Kusmartsev, Feodor V.

    2016-01-01

    Quantum computation using artificial-atoms, such as novel superconducting circuits, can be sensitively controlled by external electromagnetic fields. These fields and the self-fields attributable to the coupled artificial-atoms influence the amount of quantum correlation in the system. However, control elements that can operate without complete destruction of the entanglement of the quantum-bits are difficult to engineer. Here we investigate the possibility of using closely-spaced-linear arrays of metallic-elliptical discs as whispering gallery waveguides to control artificial-atoms. The discs confine and guide radiation through the array with small notches etched into their sides that act as scatterers. We focus on π-ring artificial-atoms, which can generate their own spontaneous fluxes. We find that the micro-discs of the waveguides can be excited by terahertz frequency fields to exhibit whispering-modes and that a quantum-phase-gate composed of π-rings can be operated under their influence. Furthermore, we gauge the level of entanglement through the concurrence measure and show that under certain magnetic conditions a series of entanglement sudden-deaths and revivals occur between the two qubits. This is important for understanding the stability and life-time of qubit operations using, for example, a phase gate in a hybrid of quantum technologies composed of control elements and artificial-atoms. PMID:27122353

  5. Whispering galleries and the control of artificial atoms.

    PubMed

    Forrester, Derek Michael; Kusmartsev, Feodor V

    2016-01-01

    Quantum computation using artificial-atoms, such as novel superconducting circuits, can be sensitively controlled by external electromagnetic fields. These fields and the self-fields attributable to the coupled artificial-atoms influence the amount of quantum correlation in the system. However, control elements that can operate without complete destruction of the entanglement of the quantum-bits are difficult to engineer. Here we investigate the possibility of using closely-spaced-linear arrays of metallic-elliptical discs as whispering gallery waveguides to control artificial-atoms. The discs confine and guide radiation through the array with small notches etched into their sides that act as scatterers. We focus on π-ring artificial-atoms, which can generate their own spontaneous fluxes. We find that the micro-discs of the waveguides can be excited by terahertz frequency fields to exhibit whispering-modes and that a quantum-phase-gate composed of π-rings can be operated under their influence. Furthermore, we gauge the level of entanglement through the concurrence measure and show that under certain magnetic conditions a series of entanglement sudden-deaths and revivals occur between the two qubits. This is important for understanding the stability and life-time of qubit operations using, for example, a phase gate in a hybrid of quantum technologies composed of control elements and artificial-atoms. PMID:27122353

  6. Dissipative quantum computing with open quantum walks

    SciTech Connect

    Sinayskiy, Ilya; Petruccione, Francesco

    2014-12-04

    An open quantum walk approach to the implementation of a dissipative quantum computing scheme is presented. The formalism is demonstrated for the example of an open quantum walk implementation of a 3 qubit quantum circuit consisting of 10 gates.

  7. Crutches and children - standing and walking

    MedlinePlus

    ... forward and apart. Walking with Crutches (No Weight Bearing on Hurt Foot or Leg) This means that ... at the feet. Walking with Crutches (Partial Weight Bearing) This means that your child can touch the ...

  8. On Convergent Probability of a Random Walk

    ERIC Educational Resources Information Center

    Lee, Y.-F.; Ching, W.-K.

    2006-01-01

    This note introduces an interesting random walk on a straight path with cards of random numbers. The method of recurrent relations is used to obtain the convergent probability of the random walk with different initial positions.

  9. Successful Statewide Walking Program Websites

    ERIC Educational Resources Information Center

    Teran, Bianca Maria; Hongu, Nobuko

    2012-01-01

    Statewide Extension walking programs are making an effort to increase physical activity levels in America. An investigation of all 20 of these programs revealed that 14 use websites as marketing and educational tools, which could prove useful as the popularity of Internet communities continues to grow. Website usability information and an analysis…

  10. Closed walks for community detection

    NASA Astrophysics Data System (ADS)

    Yang, Yang; Sun, Peng Gang; Hu, Xia; Li, Zhou Jun

    2014-03-01

    In this paper, we propose a novel measure that integrates both the concept of closed walks and clustering coefficients to replace the edge betweenness in the well-known divisive hierarchical clustering algorithm, the Girvan and Newman method (GN). The edges with the lowest value are removed iteratively until the network is degenerated into isolated nodes. The experimental results on computer generated networks and real-world networks showed that our method makes a better tradeoff of accuracy and runtime. Based on the analysis of the results, we observe that the nontrivial closed walks of order three and four can be considered as the basic elements in constructing community structures. Meanwhile, we discover that those nontrivial closed walks outperform trivial closed walks in the task of analyzing the structure of networks. The double peak structure problem is mentioned in the last part of the article. We find that our proposed method is a novel way to solve the double peak structure problem. Our work can provide us with a new perspective for understanding community structure in complex networks.

  11. Walk around the Block Curriculum.

    ERIC Educational Resources Information Center

    Center for Understanding the Built Environment, Prairie Village, KS.

    This curriculum packet contains two teacher-developed lesson plans for upper elementary students focusing on the built environment. The first lesson plan, "The Built Environment--An Integrating Theme" (Liesa Schroeder), offers suggestions for developing a walking tour around the school neighborhood, a historic area, or a city square. It finds that…

  12. Listening Walks and Singing Maps

    ERIC Educational Resources Information Center

    Cardany, Audrey Berger

    2011-01-01

    The Listening Walk by Paul Showers and illustrated by Aliki, and "It's My City: A Singing Map" by April Pulley Sayre with pictures by Denis Roche, provide two examples of texts that aid in building children's phonological awareness for reading and music. The author describes each narrative and discusses its function as a springboard to composition…

  13. A Leadership Walk across Gettysburg

    ERIC Educational Resources Information Center

    Millward, Robert E.

    2009-01-01

    School administrators find the Civil War battlefield an appropriate venue for fully appreciating the role of vision, mentoring and the power of words. The author, a professor at Indiana University of Pennsylvania, has organized leadership walks across Gettysburg for superintendents and principals for a decade. This article describes the…

  14. Behavior Management by Walking Around

    ERIC Educational Resources Information Center

    Boardman, Randolph M.

    2004-01-01

    An emerging concept from the field of business is to manage organizations by wandering around and engaging staff and consumers in informal interactions. The author extends these ideas to settings serving children and youth. In the best seller, In Search of Excellence, Peters and Waterman (1982) introduced Management by Walking Around (MBWA) as an…

  15. A Walk to the Well.

    ERIC Educational Resources Information Center

    Weir, Phil

    1994-01-01

    During a walk, an outdoor education teacher reflects on the status of outdoor education in Ottawa (Canada) and importance of maintaining a close relationship with nature. He looks for signs of an old log home site, observes a hawk's flight, discovers remains of a plastic bag in an owl pellet, and realizes that everyone is working on survival. (LP)

  16. A Walking School Bus Program Increased Students' Walking to School and Decreased Transport by Car

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Walking school buses are popular programs designed to overcome barriers and increase the numbers of children who walk to school. We tested the hypothesis that a walking school bus program would increase the proportion of children walking to school and decrease the proportion transported to school by...

  17. KidsWalk-to-School: A Guide To Promote Walking to School.

    ERIC Educational Resources Information Center

    Center for Chronic Disease Prevention and Health Promotion (DHHS/CDC), Atlanta, GA.

    This guide encourages people to create safe walking and biking routes to school, promoting four issues: physically active travel, safe and walkable routes to school, crime prevention, and health environments. The chapters include: "KidsWalk-to-School: A Guide to Promote Walking to School" (Is there a solution? Why is walking to school important?…

  18. Exam Question Exchange.

    ERIC Educational Resources Information Center

    Alexander, John J.

    1979-01-01

    Describes an exam question which challenges college freshmen, enrolled in chemistry, to derive temperature dependence of an equilibrium constant. The question requires cognitive response at the level of synthesis. (Author/SA)

  19. Questions about Adoption

    MedlinePlus

    ... Español Text Size Email Print Share Questions About Adoption Page Content Article Body What's the best way to handle my child's questions about her adoption? Many parents want to know when is the ...

  20. Burning Questions about Calories.

    ERIC Educational Resources Information Center

    Keller, J. David; Berry, Kimberly A.

    2001-01-01

    Uses questioning techniques to teach about caloric consumption and weight gain. Starts with defining questions about calories and includes the stages of measuring calories, analyzing data, and conducting inquiry research. Includes directions for the experiment. (YDS)

  1. Developmental Continuity? Crawling, Cruising, and Walking

    ERIC Educational Resources Information Center

    Adolph, Karen E.; Berger, Sarah E.; Leo, Andrew J.

    2011-01-01

    This research examined developmental continuity between "cruising" (moving sideways holding onto furniture for support) and walking. Because cruising and walking involve locomotion in an upright posture, researchers have assumed that cruising is functionally related to walking. Study 1 showed that most infants crawl and cruise concurrently prior…

  2. Reading for Meaning: Questioning

    ERIC Educational Resources Information Center

    Trinkle, Catherine

    2009-01-01

    An essential literacy skill is asking questions. Because reading comprehension strategies should be taught directly and explicitly, students need to be told that they should ask questions throughout their research and that all questions are valid. While library media specialists are not reading teachers, the work they do with students in the…

  3. Exam Question Exchange.

    ERIC Educational Resources Information Center

    Alexander, John J., Ed.

    1983-01-01

    Acceptable answers are provided for two chemistry questions. The first question is related to the prediction of the appearance of non-first-order proton nuclear magnetic resonance (NMR) spectra. The second question is related to extraterrestrial kinetic theory of gases. (JN)

  4. Exam Question Exchange.

    ERIC Educational Resources Information Center

    Alexander, John J., Ed.

    1987-01-01

    Contains two articles relating to chemistry examination questions. One provides examples of how to sequence multiple choice questions so that partial credit may be given for some responses. The second includes a question and solution dealing with stereoisomerism as a result of free radical chlorination of a nonstereoisometic substance. (TW)

  5. Improving Student Question Classification

    ERIC Educational Resources Information Center

    Heiner, Cecily; Zachary, Joseph L.

    2009-01-01

    Students in introductory programming classes often articulate their questions and information needs incompletely. Consequently, the automatic classification of student questions to provide automated tutorial responses is a challenging problem. This paper analyzes 411 questions from an introductory Java programming course by reducing the natural…

  6. Questions for Surveys

    PubMed Central

    Schaeffer, Nora Cate; Dykema, Jennifer

    2011-01-01

    We begin with a look back at the field to identify themes of recent research that we expect to continue to occupy researchers in the future. As part of this overview, we characterize the themes and topics examined in research about measurement and survey questions published in Public Opinion Quarterly in the past decade. We then characterize the field more broadly by highlighting topics that we expect to continue or to grow in importance, including the relationship between survey questions and the total survey error perspective, cognitive versus interactional approaches, interviewing practices, mode and technology, visual aspects of question design, and culture. Considering avenues for future research, we advocate for a decision-oriented framework for thinking about survey questions and their characteristics. The approach we propose distinguishes among various aspects of question characteristics, including question topic, question type and response dimension, conceptualization and operationalization of the target object, question structure, question form, response categories, question implementation, and question wording. Thinking about question characteristics more systematically would allow study designs to take into account relationships among these characteristics and identify gaps in current knowledge. PMID:24970951

  7. Making Questions Flow

    ERIC Educational Resources Information Center

    Rothstein, Dan; Santana, Luz; Minigan, Andrew P.

    2015-01-01

    Getting students to ask questions can feel like pulling teeth. How can teachers transform that feeling and create classrooms that come alive with questions? The authors, developers of the question formulation technique, suggest two simple changes: First, teachers need to give students both a structure and the opportunity to practice generating…

  8. Teachers' Classroom Questions

    ERIC Educational Resources Information Center

    Sahin, Alpaslan

    2007-01-01

    There is a large body of literature on the types of questions asked by teachers. Questions are a way that teachers use to bring students around to the correct mathematical concepts and procedures through "the negotiation of meaning for necessary condition of learning" (Voigt, 1992, p. 43). Teachers ask many questions, but we are not sure what…

  9. The Role of Transport Phenomena in Whispering Gallery Mode Optical Biosensor Performance

    NASA Astrophysics Data System (ADS)

    Gamba, Jason

    Whispering gallery mode (WGM) optical resonator sensors have emerged as promising tools for label-free detection of biomolecules in solution. These devices have even demonstrated single-molecule limits of detection in complex biological uids. This extraordinary sensitivity makes them ideal for low-concentration analytical and diagnostic measurements, but a great deal of work must be done toward understanding and optimizing their performance before they are capable of reliable quantitative measurents. The present work explores the physical processes behind this extreme sensitivity and how to best take advantage of them for practical applications of this technology. I begin by examining the nature of the interaction between the intense electromagnetic elds that build up in the optical biosensor and the biomolecules that bind to its surface. This work addresses the need for a coherent and thorough physical model that can be used to predict sensor behavior for a range of experimental parameters. While this knowledge will prove critical for the development of this technology, it has also shone a light on nonlinear thermo-optical and optical phenomena that these devices are uniquely suited to probing. The surprisingly rapid transient response of toroidal WGM biosensors despite sub-femtomolar analyte concentrations is also addressed. The development of asymmetric boundary layers around these devices under ow is revealed to enhance the capture rate of proteins from solution compared to the spherical sensors used previously. These lessons will guide the design of ow systems to minimize measurement time and consumption of precious sample, a key factor in any medically relevant assay. Finally, experimental results suggesting that WGM biosensors could be used to improve the quantitative detection of small-molecule biomarkers in exhaled breath condensate demonstrate how their exceptional sensitivity and transient response can enable the use of this noninvasive method to probe

  10. Reconstructing the behavior of walking fruit flies

    NASA Astrophysics Data System (ADS)

    Berman, Gordon; Bialek, William; Shaevitz, Joshua

    2010-03-01

    Over the past century, the fruit fly Drosophila melanogaster has arisen as almost a lingua franca in the study of animal behavior, having been utilized to study questions in fields as diverse as sleep deprivation, aging, and drug abuse, amongst many others. Accordingly, much is known about what can be done to manipulate these organisms genetically, behaviorally, and physiologically. Most of the behavioral work on this system to this point has been experiments where the flies in question have been given a choice between some discrete set of pre-defined behaviors. Our aim, however, is simply to spend some time with a cadre of flies, using techniques from nonlinear dynamics, statistical physics, and machine learning in an attempt to reconstruct and gain understanding into their behavior. More specifically, we use a multi-camera set-up combined with a motion tracking stage in order to obtain long time-series of walking fruit flies moving about a glass plate. This experimental system serves as a test-bed for analytical, statistical, and computational techniques for studying animal behavior. In particular, we attempt to reconstruct the natural modes of behavior for a fruit fly through a data-driven approach in a manner inspired by recent work in C. elegans and cockroaches.

  11. To Walk or Not to Walk?: The Hierarchy of Walking Needs

    ERIC Educational Resources Information Center

    Alfonzo, Mariela

    2005-01-01

    The multitude of quality of life problems associated with declining walking rates has impelled researchers from various disciplines to identify factors related to this behavior change. Currently, this body of research is in need of a transdisciplinary, multilevel theoretical model that can help explain how individual, group, regional, and…

  12. Measuring Victimization inside Prisons: Questioning the Questions

    ERIC Educational Resources Information Center

    Wolff, Nancy; Shi, Jing; Bachman, Ronet

    2008-01-01

    Violence and victimization inside the prison setting are accepted as facts, although the facts about their prevalence remain uncertain. Variation in the methods used to estimate rates of sexual and physical victimization contribute to the wide range in estimates appearing in the prison literature. This article focuses on the questions used in the…

  13. Question-Asking and Question-Exploring

    ERIC Educational Resources Information Center

    Sands, Lorraine; Carr, Margaret; Lee, Wendy

    2012-01-01

    The Centre of Innovation Research at Greerton Early Childhood Centre was characterised as a dispositional milieu where working theories were explored through a narrative research methodology. As the research progressed, the teachers at Greerton strengthened the way we were listening to, and watching out for young children's questions to enable…

  14. Unidirectional emission from whispering gallery modes via transformation optics

    NASA Astrophysics Data System (ADS)

    Kim, Yushin; Lee, Soo-Young; Ryu, Jung-Wan; Kim, Inbo; Han, Jae-hyung; Tae, Heung-Sik; Choi, Muhan; Min, Bumki

    2014-09-01

    It is well known from transformation optics that a light pathway can be designed with artificial materials. When a coordinate transform technique is applied to optically resonating dielectric structures, interesting phenomena can be observed as well. Generally, a long-lived whispering gallery mode (WGM) has no preferential direction of radiation because of its rotationally symmetric structure. However, if the space inside the resonator is transformed so that the discontinuity of coordinates exists, it becomes possible to reconcile directional emission with WGMs. Here, we transform only the inner space of a deformed optical cavity, e.g., the Limaçon cavity into a virtual perfect disk via a conformal mapping and show these two seemingly incompatible behaviors can be observed simultaneously. The refractive index profiles that realize the transformed space can be obtained from the conformal space transformation. The resonant mode calculated with a transformed boundary element method shows that the WGMs can restore for the deformed cavity. The Husimi function calculated for this transformed cavity shows a weighted band-like profile, which implies that the optical rays inside the cavity is maintaining its reflecting angle as is for the original cavity. However, the far-field pattern shows anisotropic emission of radiation because it is determined by tunneling through the rotationally asymmetric boundary. For example, the conformal WGMs in Limaçon and center-shifted triangular cavities exhibit bidirectional and uni-directional emission patterns in the far-field, respectively. These conformal WGM cavities with both the ultra-high quality factor and the directional light emission may be used in the realization of efficient directional light sources.

  15. Superdiffusion in a non-Markovian random walk model with a Gaussian memory profile

    NASA Astrophysics Data System (ADS)

    Borges, G. M.; Ferreira, A. S.; da Silva, M. A. A.; Cressoni, J. C.; Viswanathan, G. M.; Mariz, A. M.

    2012-09-01

    Most superdiffusive Non-Markovian random walk models assume that correlations are maintained at all time scales, e.g., fractional Brownian motion, Lévy walks, the Elephant walk and Alzheimer walk models. In the latter two models the random walker can always "remember" the initial times near t = 0. Assuming jump size distributions with finite variance, the question naturally arises: is superdiffusion possible if the walker is unable to recall the initial times? We give a conclusive answer to this general question, by studying a non-Markovian model in which the walker's memory of the past is weighted by a Gaussian centered at time t/2, at which time the walker had one half the present age, and with a standard deviation σt which grows linearly as the walker ages. For large widths we find that the model behaves similarly to the Elephant model, but for small widths this Gaussian memory profile model behaves like the Alzheimer walk model. We also report that the phenomenon of amnestically induced persistence, known to occur in the Alzheimer walk model, arises in the Gaussian memory profile model. We conclude that memory of the initial times is not a necessary condition for generating (log-periodic) superdiffusion. We show that the phenomenon of amnestically induced persistence extends to the case of a Gaussian memory profile.

  16. Walking dynamics are symmetric (enough)

    PubMed Central

    Ankaralı, M. Mert; Sefati, Shahin; Madhav, Manu S.; Long, Andrew; Bastian, Amy J.; Cowan, Noah J.

    2015-01-01

    Many biological phenomena such as locomotion, circadian cycles and breathing are rhythmic in nature and can be modelled as rhythmic dynamical systems. Dynamical systems modelling often involves neglecting certain characteristics of a physical system as a modelling convenience. For example, human locomotion is frequently treated as symmetric about the sagittal plane. In this work, we test this assumption by examining human walking dynamics around the steady state (limit-cycle). Here, we adapt statistical cross-validation in order to examine whether there are statistically significant asymmetries and, even if so, test the consequences of assuming bilateral symmetry anyway. Indeed, we identify significant asymmetries in the dynamics of human walking, but nevertheless show that ignoring these asymmetries results in a more consistent and predictive model. In general, neglecting evident characteristics of a system can be more than a modelling convenience—it can produce a better model.

  17. Nonconscious priming of elderly or youthful stereotypes influences walking velocity in healthy undergraduates.

    PubMed

    Stanislavova, Olga; Robbins, Steven J; Oatis, Carol A

    2013-03-01

    Psychological studies of "priming" effects document that covertly presented stimuli can influence behavior without participant awareness. We examined whether nonconscious priming can influence walking velocity on an instrumented walkway. Fifty-nine healthy participants were randomly assigned to unscramble sentences and answer self-concept questions containing words related to either the concepts elderly/passive or youthful/active. Walking velocity was measured before and after this priming manipulation. An ANOVA revealed a significant Group×Time interaction; the elderly/passive group showed a decrease in walking velocity over time while the youthful/active group showed an increase. None of the participants expressed any awareness of the study purpose and the experimenter was blind to group assignment. These results suggest that spoken or written material received by patients prior to gait assessments (such as casual conversations or written health inventories) might influence walking performance outside of client or clinician awareness. PMID:23021253

  18. Unpark Those Questions

    ERIC Educational Resources Information Center

    Ness, Molly

    2013-01-01

    Whenever Mr. Henderson's 3rd grade students had a question that he couldn't immediately answer or that seemed off-topic, he asked them to write the question on a sticky note and place it on a poster dubbed the "Parking Lot." His intention was to find time later to answer those questions, but too often, he said, the parking lot…

  19. Topological Galleries: A High Level User Interface for Topology Controlled Volume Rendering

    SciTech Connect

    MacCarthy, Brian; Carr, Hamish; Weber, Gunther H.

    2011-06-30

    Existing topological interfaces to volume rendering are limited by their reliance on sophisticated knowledge of topology by the user. We extend previous work by describing topological galleries, an interface for novice users that is based on the design galleries approach. We report three contributions: an interface based on hierarchical thumbnail galleries to display the containment relationships between topologically identifiable features, the use of the pruning hierarchy instead of branch decomposition for contour tree simplification, and drag-and-drop transfer function assignment for individual components. Initial results suggest that this approach suffers from limitations due to rapid drop-off of feature size in the pruning hierarchy. We explore these limitations by providing statistics of feature size as function of depth in the pruning hierarchy of the contour tree.

  20. Stress Distribution on Blasting Gallery Barrier Pillar due to Goaf Formation During Extraction

    NASA Astrophysics Data System (ADS)

    Kumar Reddy, Sandi; Sastry, Vedala Rama

    2015-09-01

    Semi-mechanised blasting gallery mining is a sustainable option to achieve higher production and productivity from underground thick coal seams. Judicious design of underground blasting gallery panel requires understanding of stress distribution on barrier pillars during different stages of extraction. This paper presents a study of stress distribution in and around barrier pillar for the different stages of extraction in the blasting gallery panel. Finite difference analysis taken up for final excavation (depillaring) in the panel with different stages of extraction. Analysis revealed that the stress transferred on barrier pillar increased as progress of excavation increased. Maximum stress was observed at a distance of 10 and 12 m from the pillar edge for virgin and goaved out panel sideby respectively, which gradually decreased towards centre of the pillar.

  1. Seasonal feeding ecology of ring-tailed lemurs: a comparison of spiny and gallery forest habitats.

    PubMed

    LaFleur, Marni; Sauther, Michelle L

    2015-01-01

    Although Lemur catta persists in many habitat types in southern Madagascar, its ecology has been primarily studied within gallery forests. We compare plant food selection and properties for ring-tailed lemurs in the spiny and gallery forests over the synchronized lactation period (September to March) that includes both the dry and wet seasons. We found no significant habitat-specific differences in the type of plant part consumed per month (i.e. flower, fruit, leaf) or between the intake of soluble carbohydrates. However, the presence and use of Tamarindus indica plants appear to elevate protein and fiber intake in the gallery forest lemurs' diets. Protein is especially important for reproductive females who incur the added metabolic costs associated with lactation; however, fiber can disrupt protein digestion. Future work should continue to investigate how variations of protein and fiber affect ring-tailed lemur dietary choice and nutrient acquisition. PMID:26022298

  2. Continuous-wave ultraviolet emission through fourth-harmonic generation in a whispering-gallery resonator.

    PubMed

    Moore, Jeremy; Tomes, Matthew; Carmon, Tal; Jarrahi, Mona

    2011-11-21

    We experimentally demonstrate continuous-wave ultraviolet emission through forth-harmonic generation in a millimeter-scale lithium niobate whispering-gallery resonator pumped with a telecommunication-compatible infrared source. The whispering-gallery resonator provides four spectral lines at ultraviolet, visible, near-infrared and infrared, which are equally spaced in frequency via the cascaded-harmonic process and span a 2-octave frequency band. Our technique relies on a variable crystal poling and high transverse order of the modes for phase-matching and a resonator quality factor of over 10(7) to allow cascaded-harmonic generation up to the fourth-harmonic at input pump powers as low as 200 mW. The compact size of the whispering gallery resonator pumped at telecommunication-compatible infrared wavelengths and the low pump power requirement make our device a promising ultraviolet light source for information storage, microscopy, and chemical analysis. PMID:22109440

  3. Cross-sectional Association between Walking Pace and Sleep-disordered Breathing.

    PubMed

    Suri, S V; Batterham, A M; Ells, L; Danjoux, G; Atkinson, G

    2015-10-01

    Sleep-disordered breathing is an important comorbidity for several diseases, including stroke. Initial screening tools comprise simple yes/no questions about known risk factors for sleep-disordered breathing, e.g., obesity, sex. But walking speed has not been investigated in this context. We examined the cross-sectional association between walking pace and sleep-disordered breathing in the population-level Multi-Ethnic Study of Atherosclerosis. A sample of 2912 men and 3213 women (46-87 years) reported perceived walking pace outside their homes. A walking pace<0.89 m/s was deemed "slow", with ≥ 0.89 m/s considered "average/brisk" according to validated thresholds. Sample prevalences were: sleep apnoea (3.5%), self-reported apnoeas (8.4%), loud snoring (20.5%), daytime tiredness (22.2%) and slow-walking pace (26.9%). The 95% CI risk differences (multivariable-adjusted) for slow vs. faster walking pace were; sleep apnoea (0.4-2.5%), self-reported apnoeas (0.1-3.8%), loud snoring (1.2-8.3%), and daytime tiredness (3.0-7.8%). Risk differences were similar between sexes. The multivariable-adjusted risk ratio indicated that slower walkers had 1.5 (95% CI: 1.0 to 2.1) times the risk of sleep apnoea vs. faster walkers. In conclusion, a slower walking speed was associated with a greater prevalence of sleep-disordered breathing, independently from other common screening factors. Therefore, a simple walking speed question may help consolidate screening for this disorder. PMID:26090878

  4. 76 FR 68101 - Safety Zone; Art Gallery Party St. Pete 2011 Fireworks Display, Tampa Bay, St. Petersburg, FL

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-03

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Art Gallery Party St. Pete 2011 Fireworks... Spa Beach in St. Petersburg, Florida during the Art Gallery Party St. Pete 2011 Fireworks Display on... to provide for the safety of event participants, spectator craft, and other vessels transiting...

  5. Positive messaging promotes walking in older adults

    PubMed Central

    Notthoff, Nanna; Carstensen, Laura L.

    2014-01-01

    Walking is among the most cost-effective and accessible means of exercise. Mounting evidence suggests that walking may help to maintain physical and cognitive independence in old age by preventing a variety of health problems. However, older Americans fall far short of meeting the daily recommendations for walking. In two studies, we examined whether considering older adults’ preferential attention to positive information may effectively enhance interventions aimed at promoting walking. In Study 1, we compared the effectiveness of positive, negative, and neutral messages to encourage walking (as measured with pedometers). Older adults who were informed about the benefits of walking walked more than those who were informed about the negative consequences of failing to walk, whereas younger adults were unaffected by framing valence. In Study 2, we examined within-person change in walking in older adults in response to positively- or negatively-framed messages over a 28-day period. Once again, positively-framed messages more effectively promoted walking than negatively-framed messages, and the effect was sustained across the intervention period. Together, these studies suggest that consideration of age-related changes in preferences for positive and negative information may inform the design of effective interventions to promote healthy lifestyles. Future research is needed to examine the mechanisms underlying the greater effectiveness of positively as opposed to negatively framed messages and the generalizability of findings to other intervention targets and other subpopulations of older adults. PMID:24956001

  6. Multi-scale nonlinear effects in whispering-gallery mode resonators

    NASA Astrophysics Data System (ADS)

    Lin, Guoping; Diallo, Souleymane; Chembo, Yanne K.

    2016-03-01

    Whispering gallery mode resonators have been the focus of many research works in recent years. They allow to study the light-matter interactions induced by the confinement of photons in nonlinear media. In particular, Brillouin Raman and Kerr nonlinearities excite the resonator at the lattice, molecular and electronic scale. This difference in spatial scales give to whispering gallery-mode resonators the potential to be central photonic components in microwave photonics, quantum optics and optoelectronics. We discuss in this communication some of the key challenges that have to be met for the understanding of Kerr, Raman and Brillouin interactions that can take place in these resonators.

  7. The whispering gallery as an optical component in the X-ray region

    SciTech Connect

    Howells, M.R.

    1995-08-01

    The whispering gallery phenomenon in acoustics has been known and studied for more than a century, and the same effect has been observed to take place with waves other than sound waves. In this paper we review the theoretical basis and attractive features of the whispering gallery as a soft x-ray optical component and indicate some of its potential applications. We then describe what may be its most unique capability which, in favorable cases, is to provide a way. to manipulate the phase difference between the s and p polarization components and thus to generate circularly or elliptically polarized soft x-rays.

  8. The influence of whispering gallery modes on the far field of ring lasers

    PubMed Central

    Szedlak, Rolf; Holzbauer, Martin; MacFarland, Donald; Zederbauer, Tobias; Detz, Hermann; Andrews, Aaron Maxwell; Schwarzer, Clemens; Schrenk, Werner; Strasser, Gottfried

    2015-01-01

    We introduce ring lasers with continuous π-phase shifts in the second order distributed feedback grating. This configuration facilitates insights into the nature of the modal outcoupling in an optical cavity. The grating exploits the asymmetry of whispering gallery modes and induces a rotation of the far field pattern. We find that this rotation can be connected to the location of the mode relative to the grating. Furthermore, the direction of rotation depends on the radial order of the whispering gallery mode. This enables a distinct identification and characterization of the mode by simple analysis of the emission beam. PMID:26573341

  9. In-fiber whispering gallery mode resonator fabricated by femtosecond laser micromaching

    NASA Astrophysics Data System (ADS)

    Shi, Leilei; Zhu, Tao; Huang, Dongmei; Liu, Min; Deng, Ming; Huang, Wei

    2015-07-01

    An in-fiber whispering gallery mode resonator fabricated by femtosecond laser micromaching is demonstrated. The cylinder resonator cavity is fabricated by scanning the D-fiber cladding with infrared femtosecond pulses along a cylindrical trace with radius of 25μm and height of 20μm. Quality factor on the order of 103 is achieved by smoothing the cavity surface with ultrasonic cleaner, which is mainly limited by the surface roughness of hundreds nanometers. Resonant characteristics and polarization dependence of the proposed resonator is also studied in detail. Our method takes a step forward to the integration of whispering gallery mode resonators.

  10. Electro-pumped whispering gallery mode ZnO microlaser array

    SciTech Connect

    Zhu, G. Y.; Li, J. T.; Tian, Z. S.; Dai, J.; Wang, Y. Y.; Li, P. L.; Xu, C. X.

    2015-01-12

    By employing vapor-phase transport method, ZnO microrods are fabricated and directly assembled on p-GaN substrate to form a heterostructural microlaser array, which avoids of the relatively complicated etching process comparing previous work. Under applied forward bias, whispering gallery mode ZnO ultraviolet lasing is obtained from the as-fabricated heterostructural microlaser array. The device's electroluminescence originates from three distinct electron-hole recombination processes in the heterojunction interface, and whispering gallery mode ultraviolet lasing is obtained when the applied voltage is beyond the lasing threshold. This work may present a significant step towards future fabrication of a facile technique for micro/nanolasers.

  11. Using Whispering-Gallery-Mode Resonators for Refractometry

    NASA Technical Reports Server (NTRS)

    Matsko, Andrey; Savchenkov, Anatoliy; Strekalov, Dmitry; Iltchenko, Vladimir; Maleki, Lute

    2010-01-01

    A method of determining the refractive and absorptive properties of optically transparent materials involves a combination of theoretical and experimental analysis of electromagnetic responses of whispering-gallery-mode (WGM) resonator disks made of those materials. The method was conceived especially for use in studying transparent photorefractive materials, for which purpose this method affords unprecedented levels of sensitivity and accuracy. The method is expected to be particularly useful for measuring temporally varying refractive and absorptive properties of photorefractive materials at infrared wavelengths. Still more particularly, the method is expected to be useful for measuring drifts in these properties that are so slow that, heretofore, the properties were assumed to be constant. The basic idea of the method is to attempt to infer values of the photorefractive properties of a material by seeking to match (1) theoretical predictions of the spectral responses (or selected features thereof) of a WGM of known dimensions made of the material with (2) the actual spectral responses (or selected features thereof). Spectral features that are useful for this purpose include resonance frequencies, free spectral ranges (differences between resonance frequencies of adjacently numbered modes), and resonance quality factors (Q values). The method has been demonstrated in several experiments, one of which was performed on a WGM resonator made from a disk of LiNbO3 doped with 5 percent of MgO. The free spectral range of the resonator was approximately equal to 3.42 GHz at wavelengths in the vicinity of 780 nm, the smallest full width at half maximum of a mode was approximately equal to 50 MHz, and the thickness of the resonator in the area of mode localization was 30 microns. In the experiment, laser power of 9 mW was coupled into the resonator with an efficiency of 75 percent, and the laser was scanned over a frequency band 9 GHz wide at a nominal wavelength of

  12. White-Light Whispering-Gallery-Mode Optical Resonators

    NASA Technical Reports Server (NTRS)

    Matsko, Andrey; Savchenkov, Anatoliy; Maleki, Lute

    2006-01-01

    Whispering-gallery-mode (WGM) optical resonators can be designed to exhibit continuous spectra over wide wavelength bands (in effect, white-light spectra), with ultrahigh values of the resonance quality factor (Q) that are nearly independent of frequency. White-light WGM resonators have potential as superior alternatives to (1) larger, conventional optical resonators in ring-down spectroscopy, and (2) optical-resonator/electro-optical-modulator structures used in coupling of microwave and optical signals in atomic clocks. In these and other potential applications, the use of white-light WGM resonators makes it possible to relax the requirement of high-frequency stability of lasers, thereby enabling the use of cheaper lasers. In designing a white-light WGM resonator, one exploits the fact that the density of the mode spectrum increases predictably with the thickness of the resonator disk. By making the resonator disk sufficiently thick, one can make the frequency differences between adjacent modes significantly less than the spectral width of a single mode, so that the spectral peaks of adjacent modes overlap, making the resonator spectrum essentially continuous. Moreover, inasmuch as the Q values of the various modes are determined primarily by surface Rayleigh scattering that does not depend on mode numbers, all the modes have nearly equal Q. By use of a proper coupling technique, one can ensure excitation of a majority of the modes. For an experimental demonstration of a white-light WGM resonator, a resonator disk 0.5-mm thick and 5 mm in diameter was made from CaF2. The shape of the resonator and the fiberoptic coupling arrangement were as shown in Figure 1. The resonator was excited with laser light having a wavelength of 1,320 nm and a spectral width of 4 kHz. The coupling efficiency exceeded 80 percent at any frequency to which the laser could be set in its tuning range, which was >100-GHz wide. The resonator response was characterized by means of ring

  13. Problem of Questioning

    ScienceCinema

    None

    2011-04-25

    Le Prof.Leprince-Ringuet, chercheur sur le plan scientifique, artistique et humain, parle de la remise en question des hommes et la remise en question scientifique fondamentale ou exemplaire- plusieurs personnes prennent la parole p.ex Jeanmairet, Adam, Gregory. Le Prof.Gregory clot la soirée en remerciant le Prof.Leprince-Ringuet

  14. Designing Great Hinge Questions

    ERIC Educational Resources Information Center

    Wiliam, Dylan

    2015-01-01

    According to author Dylan Wiliam, because lessons never go exactly as planned, teachers should build plan B into plan A. This involves designing a lesson with a "hinge" somewhere in the middle and using specific kinds of questions--what he calls hinge questions--to quickly assess students' understanding of a concept before moving on.…

  15. Are There Any Questions?

    ERIC Educational Resources Information Center

    Dauterman, Philip

    1970-01-01

    The crucial variable in good classroom teaching is the verbal behavior of the teacher. Through his questioning techniques--what questions he asks, how and when he asks them, how he replies to students, and how he stimulates students to reply to each other--the teacher can evoke a high level of class discussion and force students to go beyond the…

  16. Asking the Right Questions.

    ERIC Educational Resources Information Center

    Galvin, Ruth Mehrtens

    1990-01-01

    Like good researchers, writers about research need to be able to tell whether scientific findings are valid. Six questions, to be asked of the researcher, can help the writer explain to others. A healthy skepticism is also important; there may be signals that more questions should be asked. (MSE)

  17. Let's Switch Questioning Around

    ERIC Educational Resources Information Center

    Tovani, Cris

    2015-01-01

    English teacher Cris Tovani knows from her experiences teaching elementary school that students are naturally curious. But, too often, students are so trained to be question answerers that by the time they reach high school, they no longer form questions of their own and instead focus on trying to figure out what answer the teacher wants. Tovani…

  18. Questions About the Oceans.

    ERIC Educational Resources Information Center

    Dubach, Harold W.; Taber, Robert W.

    This book was prompted by the success of a display mounted by the National Oceanographic Data Center at the 17th International Science Fair in 1966, which enabled visiting teachers and students to ask and receive answers to questions via teletype. The book contains one hundred questions typical of those asked, together with answers ranging in…

  19. Questioning the Text.

    ERIC Educational Resources Information Center

    Harvey, Stephanie

    2001-01-01

    One way teachers can improve students' reading comprehension is to teach them to think while reading, questioning the text and carrying on an inner conversation. This involves: choosing the text for questioning; introducing the strategy to the class; modeling thinking aloud and marking the text with stick-on notes; and allowing time for guided…

  20. 1 Great Question

    ERIC Educational Resources Information Center

    Nethery, Carrie

    2011-01-01

    In this article, the author presents an ideal question that can take an art teacher and his or her students through all the levels of thought in Bloom's taxonomy--perfect for modeling the think-aloud process: "How many people is the artist inviting into this picture?" This great question always helps the students look beyond the obvious and dig…

  1. It's about the Questions

    ERIC Educational Resources Information Center

    Bearwald, Ronald R.

    2011-01-01

    The best coaching partnerships are built on conversation and listening, and they are not built on a coach giving answers to a mentee. Ronald Bearward explains how coaches can use questions to help mentees find answers for themselves. Effective questions lead to greater reflection and solutions that teachers can use now and in the future.

  2. Walk-Startup of a Two-Legged Walking Mechanism

    NASA Astrophysics Data System (ADS)

    Babković, Kalman; Nagy, László; Krklješ, Damir; Borovac, Branislav

    There is a growing interest towards humanoid robots. One of their most important characteristic is the two-legged motion - walk. Starting and stopping of humanoid robots introduce substantial delays. In this paper, the goal is to explore the possibility of using a short unbalanced state of the biped robot to quickly gain speed and achieve the steady state velocity during a period shorter than half of the single support phase. The proposed method is verified by simulation. Maintainig a steady state, balanced gait is not considered in this paper.

  3. What is a Question?

    NASA Astrophysics Data System (ADS)

    Knuth, Kevin H.

    2003-03-01

    A given question can be defined in terms of the set of statements or assertions that answer it. Application of logical inference to these sets of assertions allows one to derive the logic of inquiry among questions. There are interesting symmetries between the logics of inference and inquiry; where probability describes the degree to which a premise implies an assertion, there exists an analogous measure that describes the bearing or relevance that a question has on an outstanding issue. These have been extended to suggest that the logic of inquiry results in functional relationships analogous to, although more general than, those found in information theory. Employing lattice theory, I examine in greater detail the structure of the space of assertions and questions demonstrating that the symmetries between the logical relations in each of the spaces derive directly from the lattice structure. Furthermore, I show that while symmetries between the spaces exist, the two lattices are not isomorphic. The lattice of assertions is described by a Boolean lattice 2N, whereas the lattice of assuredly real questions is shown to be a sublattice of the free distributive lattice FD(N) = 22N. Thus there does not exist a one-to-one mapping of assertions to questions, there is no reflection symmetry between the two spaces, and questions in general do not possess complements. Last, with these lattice structures in mind, I discuss the relationship between probability, relevance, and entropy.

  4. What is a Question?

    NASA Technical Reports Server (NTRS)

    Knuth, Kevin H.; Clancy, Daniel (Technical Monitor)

    2002-01-01

    A given question can be defined in terms of the set of statements or assertions that answer it. Application of the logic of inference to this set of assertions allows one to derive the logic of inquiry among questions. There are interesting symmetries between the logics of inference and inquiry; where probability describes the degree to which a premise implies an assertion, there exists an analogous quantity that describes the bearing or relevance that a question has on an outstanding issue. These have been extended to suggest that the logic of inquiry results in functional relationships analogous to, although more general than, those found in information theory. Employing lattice theory, I examine in greater detail the structure of the space of assertions and questions demonstrating that the symmetries between the logical relations in each of the spaces derive directly from the lattice structure. Furthermore, I show that while symmetries between the spaces exist, the two lattices are not isomorphic. The lattice of assertions is described by a Boolean lattice 2(sup N) whereas the lattice of real questions is shown to be a sublattice of the free distributive lattice FD(N) = 2(sup 2(sup N)). Thus there does not exist a one-to-one mapping of assertions to questions, there is no reflection symmetry between the two spaces, and questions in general do not possess unique complements. Last, with these lattice structures in mind, I discuss the relationship between probability, relevance and entropy.

  5. Knowledge and question asking.

    PubMed

    Ibáñez Molinero, Rafael; García-Madruga, Juan Antonio

    2011-02-01

    The ability and the motivation for question asking are, or should be, some of the most important aims of education. Unfortunately, students neither ask many questions, nor good ones. The present paper is about the capacity of secondary school pupils for asking questions and how this activity depends on prior knowledge. To examine this, we use texts containing different levels of information about a specific topic: biodiversity. We found a positive relationship between the amount of information provided and the number of questions asked about the texts, supporting the idea that more knowledgeable people ask more questions. Some students were warned that there would be an exam after the reading, and this led to a diminishing number of questions asked, and yet this still did not significantly improve their exam scores. In such a case, it seems that reading was more concerned with immediacy, hindering critical thinking and the dialog between their previous ideas and the new information. Thus, question asking seems to be influenced not only by the amount of knowledge, but also by the reader's attitude towards the information. PMID:21266138

  6. Continuous limit of discrete quantum walks

    NASA Astrophysics Data System (ADS)

    M N, Dheeraj; Brun, Todd A.

    2015-06-01

    Quantum walks can be defined in two quite distinct ways: discrete-time and continuous-time quantum walks (DTQWs and CTQWs). For classical random walks, there is a natural sense in which continuous-time walks are a limit of discrete-time walks. Quantum mechanically, in the discrete-time case, an additional "coin space" must be appended for the walk to have nontrivial time evolution. Continuous-time quantum walks, however, have no such constraints. This means that there is no completely straightforward way to treat a CTQW as a limit of a DTQW, as can be done in the classical case. Various approaches to this problem have been taken in the past. We give a construction for walks on d -regular, d -colorable graphs when the coin flip operator is Hermitian: from a standard DTQW we construct a family of discrete-time walks with a well-defined continuous-time limit on a related graph. One can think of this limit as a "coined" continuous-time walk. We show that these CTQWs share some properties with coined DTQWs. In particular, we look at a spatial search by a DTQW over the two-dimensional (2D) torus (a grid with periodic boundary conditions) of size √{N }×√{N } , where it was shown that a coined DTQW can search in time O (√{N }logN ) , but a standard CTQW takes Ω (N ) time to search for a marked element. The continuous limit of the DTQW search over the 2D torus exhibits the O (√{N }logN ) scaling, like the coined walk it is derived from. We also look at the effects of graph symmetry on the limiting walk, and show that the properties are similar to those of the DTQW as shown in Krovi and Brun, Phys. Rev. A 75, 062332 (2007), 10.1103/PhysRevA.75.062332.

  7. 10 CFR 429.53 - Walk-in coolers and walk-in freezers.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... CONSUMER PRODUCTS AND COMMERCIAL AND INDUSTRIAL EQUIPMENT Certification § 429.53 Walk-in coolers and walk... product-specific information: (i) For WICF doors: The door type, R-value of the door insulation, and...

  8. Walking Programs to Promote Weight Loss among Obese and Overweight Individuals: Walking Buses for Adults

    PubMed Central

    Baker, Elizabeth H.; Milner, Adrienne N.; Campbell, Anthony D.

    2016-01-01

    Objective To assess whether the concept of a walking bus program is a viable option for increasing physical activity and weight loss among overweight and obese adults Methods A pilot study was conducted where 45overweight and obese participants were monitored over an 8 week period and their walking bus use and weight changes were measured longitudinally. Results Participants who utilized the walking bus were more likely than those who did not use the walking bus to lose weight. Black walking bus users were less likely to lose weight than non-black walking bus users. 98% of participants said they would likely participate in a walking bus program again. Conclusions Walking buses programs are a viable option to promote weight loss among overweight and obese adults. PMID:25940648

  9. Walking or Running in the Rain--A Simple Derivation of a General Solution

    ERIC Educational Resources Information Center

    Ehrmann, Andrea; Blachowicz, Tomasz

    2011-01-01

    The question whether to walk slowly or to run when it starts raining in order to stay as dry as possible has been considered for many years--and with different results, depending on the assumptions made and the mathematical descriptions for the situation. Because of the practical meaning for real life and the inconsistent results depending on the…

  10. Quantum walks with encrypted data.

    PubMed

    Rohde, Peter P; Fitzsimons, Joseph F; Gilchrist, Alexei

    2012-10-12

    In the setting of networked computation, data security can be a significant concern. Here we consider the problem of allowing a server to remotely manipulate client supplied data, in such a way that both the information obtained by the client about the server's operation and the information obtained by the server about the client's data are significantly limited. We present a protocol for achieving such functionality in two closely related models of restricted quantum computation-the boson sampling and quantum walk models. Because of the limited technological requirements of the boson scattering model, small scale implementations of this technique are feasible with present-day technology. PMID:23102287

  11. Quantum Walks with Encrypted Data

    NASA Astrophysics Data System (ADS)

    Rohde, Peter P.; Fitzsimons, Joseph F.; Gilchrist, Alexei

    2012-10-01

    In the setting of networked computation, data security can be a significant concern. Here we consider the problem of allowing a server to remotely manipulate client supplied data, in such a way that both the information obtained by the client about the server’s operation and the information obtained by the server about the client’s data are significantly limited. We present a protocol for achieving such functionality in two closely related models of restricted quantum computation—the boson sampling and quantum walk models. Because of the limited technological requirements of the boson scattering model, small scale implementations of this technique are feasible with present-day technology.

  12. Visual Acuity During Treadmill Walking

    NASA Technical Reports Server (NTRS)

    Peters, B. T.; Brady, R.; vanEmmerik, R. E. A.; Bloomberg, Jacob J.

    2006-01-01

    An awareness of the physical world is essential for successful navigation through the environment. Vision is the means by which this awareness is made possible for most people. However, without adequate compensation, the movements of the body during walking could impair vision. Previous research has shown how the eyes, head and trunk movements are coordinated to provide the compensation necessary for clear vision, but the overall effectiveness of these coordinated movements is unknown. The goal of the research presented here was to provide a direct measure of visual performance during locomotion, while also investigating the degree to which coordinated head and body movements can be altered to facilitate the goal of seeing clearly.

  13. Orbiting pairs of walking droplets

    NASA Astrophysics Data System (ADS)

    Siefert, Emmanuel; Bush, John W. M.; Oza, Anand

    2015-11-01

    Droplets may self-propel on the surface of a vibrating fluid bath, pushed forward by their own Faraday pilot-wave field. We present the results of a combined experimental and theoretical investigation of the interaction of pairs of such droplets. Particular attention is given to characterizing the system's dependence on the vibrational forcing of the bath and the impact parameter of the walking droplets. Observed criteria for the capture and stability of orbital pairs are rationalized by accompanying theoretical developments. Thanks to the NSF.

  14. Monitoring Butterfly Abundance: Beyond Pollard Walks

    PubMed Central

    Pellet, Jérôme; Bried, Jason T.; Parietti, David; Gander, Antoine; Heer, Patrick O.; Cherix, Daniel; Arlettaz, Raphaël

    2012-01-01

    Most butterfly monitoring protocols rely on counts along transects (Pollard walks) to generate species abundance indices and track population trends. It is still too often ignored that a population count results from two processes: the biological process (true abundance) and the statistical process (our ability to properly quantify abundance). Because individual detectability tends to vary in space (e.g., among sites) and time (e.g., among years), it remains unclear whether index counts truly reflect population sizes and trends. This study compares capture-mark-recapture (absolute abundance) and count-index (relative abundance) monitoring methods in three species (Maculinea nausithous and Iolana iolas: Lycaenidae; Minois dryas: Satyridae) in contrasted habitat types. We demonstrate that intraspecific variability in individual detectability under standard monitoring conditions is probably the rule rather than the exception, which questions the reliability of count-based indices to estimate and compare specific population abundance. Our results suggest that the accuracy of count-based methods depends heavily on the ecology and behavior of the target species, as well as on the type of habitat in which surveys take place. Monitoring programs designed to assess the abundance and trends in butterfly populations should incorporate a measure of detectability. We discuss the relative advantages and inconveniences of current monitoring methods and analytical approaches with respect to the characteristics of the species under scrutiny and resources availability. PMID:22859980

  15. The Recovery of Walking in Stroke Patients: A Review

    ERIC Educational Resources Information Center

    Jang, Sung Ho

    2010-01-01

    We reviewed the literature on walking recovery of stroke patients as it relates to the following subjects: epidemiology of walking dysfunction, recovery course of walking, and recovery mechanism of walking (neural control of normal walking, the evaluation methods for leg motor function, and motor recovery mechanism of leg). The recovery of walking…

  16. Rubella: Questions and Answers

    MedlinePlus

    ... of special precautions. Does the MMR vaccine cause autism? There is no scientific evidence that measles, MMR, ... other vaccine causes or increases the risk of autism. The question about a possible link between MMR ...

  17. Biology Today: Questions & Variations.

    ERIC Educational Resources Information Center

    Flannery, Maura, Ed.

    1988-01-01

    Discusses the importance of student questions as tools of instruction and as indicators of student misconceptions. Suggests different ways in which students may gain an understanding of biological concepts through discussion of popular movies and biological problems. (CW)

  18. A Teacher's Questions.

    ERIC Educational Resources Information Center

    Close, Elizabeth

    1995-01-01

    Presents questions and concerns of a teacher who served as a scoring assessor for the Early Adolescence/English Language Arts field test of the National Board for Professional Teaching Standards, run by the Educational Testing Service. (SR)

  19. Asking gender questions

    NASA Astrophysics Data System (ADS)

    Pritchard, Jonathan; Masters, Karen; Allen, James; Contenta, Filippo; Huckvale, Leo; Wilkins, Stephen; Zocchi, Alice

    2014-12-01

    Jonathan Pritchard, Karen Masters, James Allen, Filippo Contenta, Leo Huckvale, Stephen Wilkins and Alice Zocchi report on a survey of the gender of astronomers attending and asking questions at this year's UK National Astronomy Meeting.

  20. Walk and Talk: an intervention for behaviorally challenged youths.

    PubMed

    Doucette, Patricia A

    2004-01-01

    This qualitative research explored the question: Do preadolescent and adolescent youths with behavioral challenges benefit from a multimodal intervention of walking outdoors while engaging in counseling? The objective of the Walk and Talk intervention is to help the youth feel better, explore alternative behavioral choices, and learn new coping strategies and life skills by engaging in a counseling process that includes the benefits of mild aerobic exercise, and that nurtures a connection to the outdoors. The intervention utilizes a strong therapeutic alliance based on the Rogerian technique of unconditional positive regard, which is grounded and guided by the principles of attachment theory. For eight weeks, eight students (aged 9 to 13 years) from a middle school in Alberta, Canada, participated weekly in the Walk and Talk intervention. Students' self-reports indicated that they benefited from the intervention. Research triangulation with involved adults supported findings that indicated the students were making prosocial choices in behavior, and were experiencing more feelings of self-efficacy and well-being. Limitations, new research directions, and subsequent longitudinal research possibilities are discussed. PMID:15563045

  1. "The Art of Democracy": Young People's Democratic Learning in Gallery Contexts

    ERIC Educational Resources Information Center

    Lawy, Robert; Biesta, Gert; McDonnell, Jane; Lawy, Helen; Reeves, Hannah

    2010-01-01

    In this article the authors report on research which aimed to explore the opportunities for democratic action and learning in a number of artist-led gallery education projects in the south-west of England. The research takes an approach to citizenship learning and democracy that is less focused on citizenship as a specific subject in the formal…

  2. At 1050 Gallery, Block 55, similar view as WA139A25. Joshua ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    At 1050 Gallery, Block 55, similar view as WA-139-A-25. Joshua Hendy Ironworks, Sunnyvale, California, manufactured the mechanical components of this gate control unit. - Columbia Basin Project, Grand Coulee Dam & Franklin D. Roosevelt Lake, Across Columbia River, Southeast of Town of Grand Coulee, Grand Coulee, Grant County, WA

  3. Artistic Sensibility in the Studio and Gallery Model: Revisiting Process and Product

    ERIC Educational Resources Information Center

    Thompson, Geoffrey

    2009-01-01

    This paper examines the cultivation of artistic sensibility and its impact on the art therapy process and product in a community mental health center. Artistic sensibility embodies the sense of self as an artist through the integration of artistic and aesthetic attributes of self and other. The formation of a gallery to exhibit patient art was…

  4. A coaxial converter for transforming a whispering gallery mode to the HE sub 11 mode

    SciTech Connect

    Moeller, C.P.; Doane, J.L.

    1991-08-01

    A coaxial analogue of the Vlasov converter is described which transforms a whispering gallery mode into an oversize rectangular TE{sub 01} mode, which can in turn be transformed into the HE{sub 11} mode by standard techniques. 5 refs., 4 figs.

  5. Lifelong Learning for People Aged 64+ within the Contemporary Art Gallery Context

    ERIC Educational Resources Information Center

    Goulding, Anna

    2012-01-01

    This paper reports the initial findings from Contemporary Visual Art and Identity Construction--Wellbeing Amongst Older People: a two-year research project that aims to understand how the lives of older people can be improved by examining their use of contemporary visual art in the art gallery and museum. It will focus on data relating to lifelong…

  6. The Management of Higher Education Museums, Galleries and Collections (HEMGCs) in the United Kingdom.

    ERIC Educational Resources Information Center

    Kelly, Melanie

    2001-01-01

    Surveyed workers in higher education museums, galleries, and collections (HEMGCs) about threats to HEMGCs, how they contribute to their institutions and the wider community, and how they might effectively be managed. Concluded that HEMGCs provide a valuable service, that staff need the authority and funds to run them professionally, and that…

  7. Bringing Image and Language Together: A Workshop at the Lehman College Art Gallery.

    ERIC Educational Resources Information Center

    Wexler, Alice

    2001-01-01

    Discusses a ten day workshop for kindergarten and fourth grade students that centered around the art exhibit "Contemporary Chinese Art and the Literary Culture of China" held at the Lehman College Art Gallery (Bronx, New York). Explains that students created accordion books based on Xing Fei's "Red Book." (CMK)

  8. Optical apparatus for conversion of whispering-gallery modes into a free space gaussian like beam

    DOEpatents

    Stallard, B.W.; Makowski, M.A.; Byers, J.A.

    1992-05-19

    An optical converter for efficient conversion of millimeter wavelength whispering-gallery gyrotron output into a linearly polarized, free-space Gaussian-like beam is described. The converter uses a mode-converting taper and three mirror optics. The first mirror has an azimuthal tilt to eliminate the k[sub [phi

  9. Visual Culture and Literacy Online: Image Galleries as Sites of Learning

    ERIC Educational Resources Information Center

    Carpenter, B. Stephen, II; Cifuentes, Lauren

    2011-01-01

    As new media emerge in the common culture, the authors recommend that art educators adopt those media to facilitate deep understanding of visual culture and literacy. They report here on applications of an online image gallery that helps users develop ways to interpret what they see and compose. Over the past few years the authors have…

  10. Contemporary Adult Education Philosophies and Practices in Art Galleries and Museums in Canada and the UK

    ERIC Educational Resources Information Center

    Clover, Darlene E.; Bell, Lorraine

    2013-01-01

    Public art galleries and museums have been mandated to become more relevant and useful to the lived experiences of the broad communities they claim to serve. Adult education has long been part of the work of these institutions, although historically the relationship has been uneasy, and they seldom feature in the adult education literature. To…

  11. The Spiral Gallery: Non-Market Creativity and Belonging in an Australian Country Town

    ERIC Educational Resources Information Center

    Waitt, Gordon; Gibson, Chris

    2013-01-01

    This paper seeks to explore creative practice in an Australian country town, and in so doing, to unsettle market-orientated interpretations of creativity that privilege the urban. Instead of focusing on creative practice as a means to develop industries, we focus on how creativity is a means to establish a cooperative gallery space that helps to…

  12. Durability of visitable concrete sewer gallery under the effect of domestic wastewater

    NASA Astrophysics Data System (ADS)

    Salhi, Aimed; Kriker, Abdelouahed; Tioua, Tahar; Abimiloud, Youcef; Barluenga, Gonzalo

    2016-07-01

    The durability of concrete structures for the disposal of wastewater depends on their behavior when faced to different aggressions such as mechanics, chemical and biological, causing a deterioration often cementing matrix. The deterioration of recent evacuations wastewater infrastructure, made of reinforced concrete less than 15 years ago, has become an important concern. The aim of this study was to investigate the degradation and the factors responsible for the deterioration of the concrete visitable gallery of sewage from the town of Touggourt (south-east of Algeria). Thus, samples from different parts of the gallery were extracted and unaltered samples were selected as a reference. A degraded sample exposed to H2S gas and another sample of the gallery submerged into wastewater were analyzed to characterize the internal and external damage to the gallery as well as the chemical and mineralogical changes. These tests were complemented by a physical and mechanical characterization of the samples. The experimental results showed the strong anisotropy of both internal and external damage.

  13. Linear and nonlinear behavior of crystalline optical whispering gallery mode resonators

    NASA Technical Reports Server (NTRS)

    Savchenkov, Anatoliy A.; Matsko, Andrey B.; Ilchenko, Vladimir S.; Maleki, Lute

    2004-01-01

    We demonstrate strong nonlinear behavior of high-Q whispering gallery mode (WGM) resonators made out of various crystals adn devices based on the resonators. The maximum WGM optical Q-fact or achieved at room temperature exceeds 2X10 to the tenth power.

  14. Light absorption enhancement in thin-film solar cells using whispering gallery modes in dielectric nanospheres

    SciTech Connect

    Grandidier, Jonathan; Callahan, Dennis M; Munday, Jeremy N; Atwater, Harry A.

    2011-03-07

    A novel approach to increasing light absorption in thin-film solar cells is demonstrated. This new method involves redirecting the incident sunlight into the cell via coupling to the whispering gallery modes of dielectric spheres, which lie atop the cell. Such a scheme leads to a predicted current enhancement of >12% for a-Si.

  15. The National Gallery of Canada's Theme Rooms: Exploring the Educational Exhibition.

    ERIC Educational Resources Information Center

    Newlands, Anne

    1991-01-01

    Didactic space for education within art museums is explored, and the development of four such areas in the National Gallery of Canada (Ottawa) is traced. Evaluation of the resulting Theme Rooms through observations of and interviews with 112 patrons will increase their appeal and potential for education. (SLD)

  16. Efficient upconversion of subterahertz radiation in a high-Q whispering gallery resonator.

    PubMed

    Strekalov, D V; Savchenkov, A A; Matsko, A B; Yu, N

    2009-03-15

    We demonstrate efficient upconversion of subterahertz radiation into the optical domain in a high-Q whispering gallery mode resonator with quadratic optical nonlinearity. The 5x10(-3) power conversion efficiency of a cw 100 GHz signal is achieved with only 16 mW of optical pump. PMID:19282908

  17. The Artist-Led Pedagogic Process in the Contemporary Art Gallery: Developing a Meaning Making Framework

    ERIC Educational Resources Information Center

    Pringle, Emily

    2009-01-01

    Drawing on recent research which examined how selected artist educators perceive themselves as arts practitioners and analysed how these constructions inform their pedagogy, this article proposes a framework of meaning making in the art gallery. Art practice is defined as a process of conceptual and experiential enquiry which embraces inspiration,…

  18. Whispering gallery mode resonators for frequency metrology applications

    NASA Astrophysics Data System (ADS)

    Baumgartel, Lukas

    This dissertation describes an investigation into the use of whispering gallery mode (WGM) resonators for applications towards frequency reference and metrology. Laser stabilization and the measurement of optical frequencies have enabled myriad technologies of both academic and commercial interest. A technology which seems to span both motivations is optical atomic clocks. These devices are virtually unimaginable without the ultra stable lasers plus frequency measurement and down-conversion afforded by Fabry Perot (FP) cavities and model-locked laser combs, respectively. However, WGM resonators can potentially perform both of these tasks while having the distinct advantages of compactness and simplicity. This work represents progress towards understanding and mitigating the performance limitations of WGM cavities for such applications. A system for laser frequency stabilization to a the cavity via the Pound-Drever-Hall (PDH) method is described. While the laser lock itself is found to perform at the level of several parts in 1015, a variety of fundamental and technical mechanisms destabilize the WGM frequency itself. Owing to the relatively large thermal expansion coefficients in optical crystals, environmental temperature drifts set the stability limit at time scales greater than the thermal relaxation time of the crystal. Uncompensated, these drifts pull WGM frequencies about 3 orders of magnitude more than they would in an FP cavity. Thus, two temperature compensation schemes are developed. An active scheme measures and stabilizes the mode volume temperature to the level of several nK, reducing the effective temperature coefficient of the resonator to 1.7x10-7 K-1; simulations suggest that the value could eventually be as low as 3.5x10-8 K-1, on par with the aforementioned FP cavities. A second, passive scheme is also described, which employs a heterogeneous resonator structure that capitalizes on the thermo-mechanical properties of one material and the optical

  19. Spatial search by quantum walk

    SciTech Connect

    Childs, Andrew M.; Goldstone, Jeffrey

    2004-08-01

    Grover's quantum search algorithm provides a way to speed up combinatorial search, but is not directly applicable to searching a physical database. Nevertheless, Aaronson and Ambainis showed that a database of N items laid out in d spatial dimensions can be searched in time of order {radical}(N) for d>2, and in time of order {radical}(N) poly(log N) for d=2. We consider an alternative search algorithm based on a continuous-time quantum walk on a graph. The case of the complete graph gives the continuous-time search algorithm of Farhi and Gutmann, and other previously known results can be used to show that {radical}(N) speedup can also be achieved on the hypercube. We show that full {radical}(N) speedup can be achieved on a d-dimensional periodic lattice for d>4. In d=4, the quantum walk search algorithm takes time of order {radical}(N) poly(log N), and in d<4, the algorithm does not provide substantial speedup.

  20. Interface Reconstruction with Directional Walking

    SciTech Connect

    Yao, J

    2009-05-22

    Young's interface reconstruction with three-dimensional arbitrary mesh, in general, is rather tedious to implement compared to the case of a regular mesh. The main difficulty comes from the construction of a planar facet that bounds a certain volume inside a cell. Unlike the five basic configurations with a Cartesian mesh, there can be a great number of different configurations in the case of a general mesh. We represent a simple method that can derive the topology/geometry of the intersection of arbitrary planar objects in a uniform way. The method is based on a directional walking on the surface of objects, and links the intersection points with the paths of the walking naturally defining the intersection of objects. The method works in both two and three dimensions. The method does not take advantage of convexity, thus decomposition of an object is not necessary. Therefore, the solution with this method will have a reduced number of edges and less data storage, compared with methods that use shape decomposition. The treatment is general for arbitrary polyhedrons, and no look-up tables are needed. The same operation can easily be extended for curved geometry. The implementation of this new algorithm shall allow the interface reconstruction on an arbitrary mesh to be as simple as it is on a regular mesh. Furthermore, we exactly compute the integral of partial cell volume bounded by quadratic interface. Therefore, interface reconstruction with higher than second order accuracy can be achieved on an arbitrary mesh.

  1. A Simple Exoskeleton That Assists Plantarflexion Can Reduce the Metabolic Cost of Human Walking

    PubMed Central

    Malcolm, Philippe; Derave, Wim; Galle, Samuel; De Clercq, Dirk

    2013-01-01

    Background Even though walking can be sustained for great distances, considerable energy is required for plantarflexion around the instant of opposite leg heel contact. Different groups attempted to reduce metabolic cost with exoskeletons but none could achieve a reduction beyond the level of walking without exoskeleton, possibly because there is no consensus on the optimal actuation timing. The main research question of our study was whether it is possible to obtain a higher reduction in metabolic cost by tuning the actuation timing. Methodology/Principal Findings We measured metabolic cost by means of respiratory gas analysis. Test subjects walked with a simple pneumatic exoskeleton that assists plantarflexion with different actuation timings. We found that the exoskeleton can reduce metabolic cost by 0.18±0.06 W kg−1 or 6±2% (standard error of the mean) (p = 0.019) below the cost of walking without exoskeleton if actuation starts just before opposite leg heel contact. Conclusions/Significance The optimum timing that we found concurs with the prediction from a mathematical model of walking. While the present exoskeleton was not ambulant, measurements of joint kinetics reveal that the required power could be recycled from knee extension deceleration work that occurs naturally during walking. This demonstrates that it is theoretically possible to build future ambulant exoskeletons that reduce metabolic cost, without power supply restrictions. PMID:23418524

  2. Treadmill walking is not equivalent to overground walking for the study of walking smoothness and rhythmicity in older adults.

    PubMed

    Row Lazzarini, Brandi S; Kataras, Theodore J

    2016-05-01

    Treadmills are appealing for gait studies, but some gait mechanics are disrupted during treadmill walking. The purpose of this study was to examine the effects of speed and treadmill walking on walking smoothness and rhythmicity of 40 men and women between the ages of 70-96 years. Gait smoothness was examined during overground (OG) and treadmill (TM) walking by calculating the harmonic ratio from linear accelerations measured at the level of the lumbar spine. Rhythmicity was quantified as the stride time standard deviation. TM walking was performed at two speeds: a speed matching the natural OG walk speed (TM-OG), and a preferred TM speed (PTM). A dual-task OG condition (OG-DT) was evaluated to determine if TM walking posed a similar cognitive challenge. Statistical analysis included a one-way Analysis of Variance with Bonferroni corrected post hoc comparisons and the Wilcoxon signed rank test for non-normally distributed variables. Average PTM speed was slower than OG. Compared to OG, those who could reach the TM-OG speed (74.3% of sample) exhibited improved ML smoothness and rhythmicity, and the slower PTM caused worsened vertical and AP smoothness, but did not affect rhythmicity. PTM disrupted smoothness and rhythmicity differently than the OG-DT condition, likely due to reduced speed. The use of treadmills for gait smoothness and rhythmicity studies in older adults is problematic; some participants will not achieve OG speed during TM walking, walking at the TM-OG speed artificially improves rhythmicity and ML smoothness, and walking at the slower PTM speed worsens vertical and AP gait smoothness. PMID:27131175

  3. Walking there: environmental influence on walking-distance estimation.

    PubMed

    Iosa, M; Fusco, A; Morone, G; Paolucci, S

    2012-01-01

    In a dark environment, when vision is excluded, humans are usually able to walk towards a target the position of which was previously memorized. Changes in spatio-temporal gait parameters, the presence of obstacles on the ground or pathway tilt can affect their performances. The aim of this study was to investigate the influence of the environment on this ability. We have enrolled sixty healthy subjects, separately tested in a small indoor and in an outdoor open-field environment. In experiment 1, significant differences were found between 15 indoor and 15 outdoor blindfolded walkers. According to previous studies, the distances walked outdoors were not significantly different from the three-tested target's distances (3m, 6m and 10m). Conversely, a systematic and significant undershooting was observed for blindfolded indoor walkers for all the three distances (errors: -0.34, -0.73 and -1.99m, respectively). This indoor undershooting was found related to shorter steps not compensated by any increment of the step number. In experiment 2, also the perception of the indoor distance resulted underestimated in other two tested groups of 15 subjects each. But the perceived distance resulted poorly correlated with motor performances (R=0.23, p=0.410). In spite of the fact that the errors were consistent among trials, when indoor walkers could not access to environmental acoustic features, their performance resulted highly variable among subjects, but it improved, on average. At the light of these results, the environment seems acting as a selective tuning between different strategies. PMID:21925542

  4. Web-Based Walk-Throughs

    ERIC Educational Resources Information Center

    Granada, Janet; Vriesenga, Michael

    2008-01-01

    Walk-through classroom observations are an effective way for principals to learn about and shape instruction and culture in their schools. But many principals don't use walk-throughs to their potential because of the time it takes to store, process, analyze, and give feedback. To facilitate the use of this valuable observation tool, the Kentucky…

  5. Walking in circles: a modelling approach

    PubMed Central

    Maus, Horst-Moritz; Seyfarth, Andre

    2014-01-01

    Blindfolded or disoriented people have the tendency to walk in circles rather than on a straight line even if they wanted to. Here, we use a minimalistic walking model to examine this phenomenon. The bipedal spring-loaded inverted pendulum exhibits asymptotically stable gaits with centre of mass (CoM) dynamics and ground reaction forces similar to human walking in the sagittal plane. We extend this model into three dimensions, and show that stable walking patterns persist if the leg is aligned with respect to the body (here: CoM velocity) instead of a world reference frame. Further, we demonstrate that asymmetric leg configurations, which are common in humans, will typically lead to walking in circles. The diameter of these circles depends strongly on parameter configuration, but is in line with empirical data from human walkers. Simulation results suggest that walking radius and especially direction of rotation are highly dependent on leg configuration and walking velocity, which explains inconsistent veering behaviour in repeated trials in human data. Finally, we discuss the relation between findings in the model and implications for human walking. PMID:25056215

  6. Walking in circles: a modelling approach.

    PubMed

    Maus, Horst-Moritz; Seyfarth, Andre

    2014-10-01

    Blindfolded or disoriented people have the tendency to walk in circles rather than on a straight line even if they wanted to. Here, we use a minimalistic walking model to examine this phenomenon. The bipedal spring-loaded inverted pendulum exhibits asymptotically stable gaits with centre of mass (CoM) dynamics and ground reaction forces similar to human walking in the sagittal plane. We extend this model into three dimensions, and show that stable walking patterns persist if the leg is aligned with respect to the body (here: CoM velocity) instead of a world reference frame. Further, we demonstrate that asymmetric leg configurations, which are common in humans, will typically lead to walking in circles. The diameter of these circles depends strongly on parameter configuration, but is in line with empirical data from human walkers. Simulation results suggest that walking radius and especially direction of rotation are highly dependent on leg configuration and walking velocity, which explains inconsistent veering behaviour in repeated trials in human data. Finally, we discuss the relation between findings in the model and implications for human walking. PMID:25056215

  7. Excited Random Walk in One Dimension

    NASA Astrophysics Data System (ADS)

    Antal, Tibor

    2005-03-01

    We study the k-excited random walk, in which each site initially contains k cookies, and a random walk that is at a site that contains at least one cookie eats a cookie and then hops to the right with probability p and to the left with probability q=1-p. If the walk hops from an empty site, there is no bias. For the 1-excited walk on the half-line (each site initially contains one cookie), the probability of first returning to the starting point at time t scales as t-1-q. We also derive the probability distribution of the position of the leftmost uneaten cookie in the large time limit. For the infinite line, the probability distribution of the position of the 1-excited walk has an unusual anomaly at the origin and the distributions of positions for the leftmost and rightmost uneaten cookie develop a power-law singularity at the origin. The 2-excited walk on the infinite line exhibits peculiar features in the regime p>3/4, where the walk is transient, including a mean displacement that grows as t^ν, with ν>12 dependent on p, and a breakdown of scaling for the probability distribution of the walk.

  8. The excited random walk in one dimension

    NASA Astrophysics Data System (ADS)

    Antal, T.; Redner, S.

    2005-03-01

    We study the excited random walk, in which a walk that is at a site that contains cookies eats one cookie and then hops to the right with probability p and to the left with probability q = 1 - p. If the walk hops onto an empty site, there is no bias. For the 1-excited walk on the half-line (one cookie initially at each site), the probability of first returning to the starting point at time t scales as t-(2-p). Although the average return time to the origin is infinite for all p, the walk eats, on average, only a finite number of cookies until this first return when p < 1/2. For the infinite line, the probability distribution for the 1-excited walk has an unusual anomaly at the origin. The positions of the leftmost and rightmost uneaten cookies can be accurately estimated by probabilistic arguments and their corresponding distributions have power-law singularities. The 2-excited walk on the infinite line exhibits peculiar features in the regime p > 3/4, where the walk is transient, including a mean displacement that grows as tν, with \

  9. Brownian Optimal Stopping and Random Walks

    SciTech Connect

    Lamberton, D.

    2002-06-05

    One way to compute the value function of an optimal stopping problem along Brownian paths consists of approximating Brownian motion by a random walk. We derive error estimates for this type of approximation under various assumptions on the distribution of the approximating random walk.

  10. Welly-Walks for Science Learning

    ERIC Educational Resources Information Center

    Fradley, Carol

    2006-01-01

    This article discusses how a regular walk in the wind or the rain can help develop science knowledge and skills. The author describes one "welly-walk" and links it to National Curriculum for England requirements so that readers can see how easy it is. (Contains 1 figure and 1 box.)

  11. Walks: An Effective Approach to Learning.

    ERIC Educational Resources Information Center

    Wineberg, Lenore Peachin

    1997-01-01

    Whether planned or spontaneous, walks offer young children unexpected pleasures and discoveries about their environment. This article describes five strategies for using walks in early childhood programs (plan, gather information, develop safety rules, integrate with the curriculum, assess what has been learned), as well as specific indoor,…

  12. Land Use, Residential Density, and Walking

    PubMed Central

    Rodríguez, Daniel A.; Evenson, Kelly R.; Diez Roux, Ana V.; Brines, Shannon J.

    2009-01-01

    Background The neighborhood environment may play a role in encouraging sedentary patterns, especially for middle-aged and older adults. Purpose Associations between walking and neighborhood population density, retail availability, and land use distribution were examined using data from a cohort of adults aged 45 to 84 years old. Methods Data from a multi-ethnic sample of 5529 adult residents of Baltimore MD, Chicago IL, Forsyth County NC, Los Angeles CA, New York NY, and St. Paul MN, enrolled in the Multi-Ethnic Study of Atherosclerosis in 2000–2002 were linked to secondary land use and population data. Participant reports of access to destinations and stores and objective measures of the percentage of land area in parcels devoted to retail land uses, the population divided by land area in parcels, and the mixture of uses for areas within 200m of each participant's residence were examined. Multinomial logistic regression was used to investigate associations of self-reported and objective neighborhood characteristics with walking. All analyses were conducted in 2008 and 2009. Results After adjustment for individual-level characteristics and neighborhood connectivity, higher density, greater land area devoted to retail uses, and self-reported measures of proximity of destinations and ease of walking to places were each related to walking. In models including all land use measures, population density was positively associated with walking to places and with walking for exercise for more than 90 min/wk both relative to no walking. Availability of retail was associated with walking to places relative to not walking, having a more proportional mix of land uses was associated with walking for exercise for more than 90 min/wk, while self-reported ease of access to places was related to higher levels of exercise walking both relative to not walking. Conclusions Residential density and the presence of retail uses are related to various walking behaviors. Efforts to

  13. The Effects of Walking Surface on the Gait Pattern of Children With Idiopathic Toe Walking.

    PubMed

    Fanchiang, Hsinchen Daniel; Geil, Mark Daniel; Wu, Jianhua; Ajisafe, Toyin; Chen, Yu-Ping

    2016-06-01

    Idiopathic toe walking treatments are not conclusively effective. This study investigated the effects of walking surface on gait parameters in children with idiopathic toe walking. Fifteen children with idiopathic toe walking and 15 typically developing children aged 4 to 10 years completed the study, which included a barefoot gait exam over three 4-m walkways. Each of the walkways was covered with a different surface: vinyl tile, carpet, and pea gravel. Temporal-spatial parameters were recorded along with a measure of early heel rise (HR32). Children with idiopathic toe walking and typically developing children shared similarly changed gait patterns on each surfaces. Only HR32 was significantly different between the groups (P < .001). Children with idiopathic toe walking showed significantly less toe-walking on the gravel walkway (P < .001). Walking surface plays a significant role in altering gait patterns in both children with idiopathic toe walking and typically developing children. Walking on a gravel surface should be further explored for idiopathic toe walking. PMID:26733505

  14. Efficient quantum walk on a quantum processor.

    PubMed

    Qiang, Xiaogang; Loke, Thomas; Montanaro, Ashley; Aungskunsiri, Kanin; Zhou, Xiaoqi; O'Brien, Jeremy L; Wang, Jingbo B; Matthews, Jonathan C F

    2016-01-01

    The random walk formalism is used across a wide range of applications, from modelling share prices to predicting population genetics. Likewise, quantum walks have shown much potential as a framework for developing new quantum algorithms. Here we present explicit efficient quantum circuits for implementing continuous-time quantum walks on the circulant class of graphs. These circuits allow us to sample from the output probability distributions of quantum walks on circulant graphs efficiently. We also show that solving the same sampling problem for arbitrary circulant quantum circuits is intractable for a classical computer, assuming conjectures from computational complexity theory. This is a new link between continuous-time quantum walks and computational complexity theory and it indicates a family of tasks that could ultimately demonstrate quantum supremacy over classical computers. As a proof of principle, we experimentally implement the proposed quantum circuit on an example circulant graph using a two-qubit photonics quantum processor. PMID:27146471

  15. Interventions to Improve Walking in Older Adults

    PubMed Central

    Brach, Jennifer S.; VanSwearingen, Jessie M.

    2013-01-01

    Interventions to improve walking in older adults have historically been multifactorial (i.e. strengthening, endurance and flexibility programs) focusing on improving the underlying impairments. These impairment-based programs have resulted in only modest improvements in walking. In older adults, walking is slow, less stable, inefficient, and the timing and coordination of stepping with postures and phases of gait is poor. We argue the timing and coordination problems are evidence of the loss of motor skill in walking. Taking a lesson from the sports world and from neurorehabilitation, task-oriented motor learning exercise is an essential component of training to improve motor skill and may be a beneficial approach to improving walking in older adults. In this article we: 1) briefly review the current literature regarding impairment-based interventions for improving mobility, 2) discuss why the results have been only modest, and 3) suggest an alternative approach to intervention (i.e. task oriented motor learning). PMID:24319641

  16. Efficient quantum walk on a quantum processor

    PubMed Central

    Qiang, Xiaogang; Loke, Thomas; Montanaro, Ashley; Aungskunsiri, Kanin; Zhou, Xiaoqi; O'Brien, Jeremy L.; Wang, Jingbo B.; Matthews, Jonathan C. F.

    2016-01-01

    The random walk formalism is used across a wide range of applications, from modelling share prices to predicting population genetics. Likewise, quantum walks have shown much potential as a framework for developing new quantum algorithms. Here we present explicit efficient quantum circuits for implementing continuous-time quantum walks on the circulant class of graphs. These circuits allow us to sample from the output probability distributions of quantum walks on circulant graphs efficiently. We also show that solving the same sampling problem for arbitrary circulant quantum circuits is intractable for a classical computer, assuming conjectures from computational complexity theory. This is a new link between continuous-time quantum walks and computational complexity theory and it indicates a family of tasks that could ultimately demonstrate quantum supremacy over classical computers. As a proof of principle, we experimentally implement the proposed quantum circuit on an example circulant graph using a two-qubit photonics quantum processor. PMID:27146471

  17. Go naked: diapers affect infant walking.

    PubMed

    Cole, Whitney G; Lingeman, Jesse M; Adolph, Karen E

    2012-11-01

    In light of cross-cultural and experimental research highlighting effects of childrearing practices on infant motor skill, we asked whether wearing diapers, a seemingly innocuous childrearing practice, affects infant walking. Diapers introduce bulk between the legs, potentially exacerbating infants' poor balance and wide stance. We show that walking is adversely affected by old-fashioned cloth diapers, and that even modern disposable diapers - habitually worn by most infants in the sample - incur a cost relative to walking naked. Infants displayed less mature gait patterns and more missteps and falls while wearing diapers. Thus, infants' own diapers constitute an ongoing biomechanical perturbation while learning to walk. Furthermore, shifts in diapering practices may have contributed to historical and cross-cultural differences in infant walking. PMID:23106732

  18. Strongly trapped two-dimensional quantum walks

    NASA Astrophysics Data System (ADS)

    Kollár, B.; Kiss, T.; Jex, I.

    2015-02-01

    Discrete time quantum walks (DTQWs) are nontrivial generalizations of random walks with a broad scope of applications. In particular, they can be used as computational primitives, and they are suitable tools for simulating other quantum systems. DTQWs usually spread ballistically due to their quantumness. In some cases, however, they can remain localized at their initial state (trapping). The trapping and other fundamental properties of DTQWs are determined by the choice of the coin operator. We introduce and analyze a type of walks driven by a coin class leading to strong trapping, complementing the known list of walks. This class of walks exhibits a number of exciting properties with possible applications ranging from light pulse trapping in a medium to topological effects and quantum search.

  19. Efficient quantum walk on a quantum processor

    NASA Astrophysics Data System (ADS)

    Qiang, Xiaogang; Loke, Thomas; Montanaro, Ashley; Aungskunsiri, Kanin; Zhou, Xiaoqi; O'Brien, Jeremy L.; Wang, Jingbo B.; Matthews, Jonathan C. F.

    2016-05-01

    The random walk formalism is used across a wide range of applications, from modelling share prices to predicting population genetics. Likewise, quantum walks have shown much potential as a framework for developing new quantum algorithms. Here we present explicit efficient quantum circuits for implementing continuous-time quantum walks on the circulant class of graphs. These circuits allow us to sample from the output probability distributions of quantum walks on circulant graphs efficiently. We also show that solving the same sampling problem for arbitrary circulant quantum circuits is intractable for a classical computer, assuming conjectures from computational complexity theory. This is a new link between continuous-time quantum walks and computational complexity theory and it indicates a family of tasks that could ultimately demonstrate quantum supremacy over classical computers. As a proof of principle, we experimentally implement the proposed quantum circuit on an example circulant graph using a two-qubit photonics quantum processor.

  20. Question Their Answers

    NASA Astrophysics Data System (ADS)

    Royce, Brenda

    2004-10-01

    Brenda Royce has been teaching high school chemistry and physics for nine years, and is currently science department chair at University High School in Fresno, CA, a college prep charter school on the CSU Fresno campus. She also enjoys coaching Science Olympiad, and working with science and math student teachers as a workshop leader and mentor teacher through the Science and Math Education Center at CSUF. Prior to teaching, she worked in analytical and environmental chemistry for several years. Brenda shares with us her strategy of answering students' questions by "questioning their answers."

  1. Walking Capacity of Bariatric Surgery Candidates

    PubMed Central

    King, WC; Engel, SG; Elder, KA; Chapman, WH; Eid, GM; Wolfe, BM; Belle, SH

    2011-01-01

    Background This study characterizes the walking limitations of bariatric surgery candidates by age and body mass index (BMI) and determines factors independently associated with walking capacity. Setting Multi-institutional at research university hospitals in the United States. Methods 2458 participants of the Longitudinal Assessment of Bariatric Surgery study (age: 18-78 y, BMI: 33-94 kg/m2) attended a pre-operative research visit. Walking capacity was measured via self-report and the 400 meter Long Distance Corridor Walk (LDCW). Results Almost two-thirds (64%) of subjects reported limitations walking several blocks, 48% had an objectively-defined mobility deficit, and 16% reported at least some walking aid use. In multivariable analysis, BMI, older age, lower income and greater bodily pain were independently associated (p<.05) with walking aid use, physical discomfort during the LDCW, inability to complete the LDCW, and slower time to complete the LDCW. Female sex, Hispanic ethnicity (but not race), higher resting heart rate, history of smoking, several comoribidities (history of stroke, ischemic heart disease, diabetes, asthma, sleep apnea, venous edema with ulcerations), and depressive symptoms were also independently related (p<.05) to at least one measure of reduced walking capacity. Conclusions Walking limitations are common in bariatric surgery candidates, even among the least severely obese and youngest patients. Physical activity counseling must be tailored to individuals' abilities. While several factors identified in this study (e.g., BMI, age, pain, comorbidities) should be considered, directly assessing walking capacity will facilitate appropriate goal-setting. PMID:21937285

  2. Quantum walking in curved spacetime

    NASA Astrophysics Data System (ADS)

    Arrighi, Pablo; Facchini, Stefano; Forets, Marcelo

    2016-08-01

    A discrete-time quantum walk (QW) is essentially a unitary operator driving the evolution of a single particle on the lattice. Some QWs admit a continuum limit, leading to familiar PDEs (e.g., the Dirac equation). In this paper, we study the continuum limit of a wide class of QWs and show that it leads to an entire class of PDEs, encompassing the Hamiltonian form of the massive Dirac equation in (1+1) curved spacetime. Therefore, a certain QW, which we make explicit, provides us with a unitary discrete toy model of a test particle in curved spacetime, in spite of the fixed background lattice. Mathematically, we have introduced two novel ingredients for taking the continuum limit of a QW, but which apply to any quantum cellular automata: encoding and grouping.

  3. Asking Questions about Participation

    ERIC Educational Resources Information Center

    Davies, Ian; Flanagan, Bernie; Hogarth, Sylvia; Mountford, Paula; Philpott, Jenny

    2009-01-01

    We raise questions about young people's participation in light of findings from a project ("Democracy through Citizenship") funded by the Joseph Rowntree Reform Trust Limited, and managed by the Institute for Citizenship. Following a six-month feasibility study the project took place over a three-year period in one local authority in the north of…

  4. Asking the Right Questions

    ERIC Educational Resources Information Center

    Lord, Rob

    2011-01-01

    As a student teacher at Nottingham Trent University, the author explored the issues surrounding children asking investigable questions in science and the repertoire of strategies that could be employed by teachers in the classroom to support this process. His project was carried out in an inner-city primary school in Nottingham. The four focus…

  5. Question: Who Can Vote?

    ERIC Educational Resources Information Center

    Rodeheaver, Misty D.; Haas, Mary E.

    2008-01-01

    This year's rollercoaster primary elections and the pending national election, with an anticipated record voter turnout, provide the perfect backdrop for an examination of the questions: (1) Who can vote?; and (2) Who will vote? Historically, the American government refused voting rights to various groups based on race, gender, age, and even…

  6. My Favorite Exam Question

    ERIC Educational Resources Information Center

    Styer, Dan

    2015-01-01

    My favorite exam question comes from the final exam in an introductory mechanics course: "A rolling 31 ton railroad boxcar collides with a stationary flatcar. The coupling mechanism activates so the cars latch together and roll down the track attached. Of the initial kinetic energy, 38% dissipates as heat, sound, vibrations, mechanical…

  7. A Question of Character

    ERIC Educational Resources Information Center

    Stuart, Reginald

    2010-01-01

    When intern placement veteran Jacqueline Perkins begins counseling students at Florida A&M University (FAMU) about their prospects for getting well-paying, security-related jobs with the federal government, she confronts the 800-pound gorilla in the room--the question of whether a student has been convicted of or pleaded guilty to a misdemeanor.…

  8. More Fermi questions

    NASA Astrophysics Data System (ADS)

    Bouffard, Karen

    1999-09-01

    "Fermi" questions are a popular component of most Physics Olympics meets. Asking students to make a reasonable assumption about a problem and give answers in terms of order of magnitude is not only a great challenge for a competition, but is also a valued teaching strategy in the classroom.

  9. Exam Question Exchange.

    ERIC Educational Resources Information Center

    Alexander, John J., Ed.

    1978-01-01

    Two exam questions are presented. One suitable for advanced undergraduate or beginning graduate courses in organic chemistry, is on equivalent expressions for the description of several pericyclic reactions. The second, for general chemistry students, asks for an estimation of the rate of decay of a million-year-old Uranium-238 sample. (BB)

  10. A question of choice.

    PubMed

    Grabiner, Gene

    2011-01-01

    Women's reproductive rights, reproductive health, and constitutional privacy rights in the United States are addressed in light of the contemporary onslaught of the Christian Right. The misuse of State power by fundamentalist social forces in America is critiqued. The article also briefly reviews the question of State control over women's bodies. PMID:21696627

  11. The Compensation Question

    ERIC Educational Resources Information Center

    Richwine, Jason; Biggs, Andrew; Mishel, Lawrence; Roy, Joydeep

    2012-01-01

    Over the past few years, as cash-strapped states and school districts have faced tough budget decisions, spending on teacher compensation has come under the microscope. The underlying question is whether, when you take everything into account, today's teachers are fairly paid, underpaid, or overpaid. In this forum, two pairs of respected…

  12. A Question of Choice

    PubMed Central

    2011-01-01

    Women's reproductive rights, reproductive health, and constitutional privacy rights in the United States are addressed in light of the contemporary onslaught of the Christian Right. The misuse of State power by fundamentalist social forces in America is critiqued. The article also briefly reviews the question of State control over women's bodies. PMID:21696627

  13. Questioning and Experimentation

    ERIC Educational Resources Information Center

    Mutanen, Arto

    2014-01-01

    The paper is a philosophical analysis of experimentation. The philosophical framework of the analysis is the interrogative model of inquiry developed by Hintikka. The basis of the model is explicit and well-formed logic of questions and answers. The framework allows us to formulate a flexible logic of experimentation. In particular, the formulated…

  14. My Favorite Exam Question

    NASA Astrophysics Data System (ADS)

    Styer, Dan

    2015-12-01

    My favorite exam question comes from the final exam in an introductory mechanics course: A rolling 31 ton railroad boxcar collides with a stationary flatcar. The coupling mechanism activates so the cars latch together and roll down the track attached. Of the initial kinetic energy, 38% dissipates as heat, sound, vibrations, mechanical deformation, and so forth. How much does the flatcar weigh?

  15. [The gallery forests of the São Francisco river as corridors for Euglossine bees (Hymenoptera: Apidae) from tropical rainforests].

    PubMed

    Moura, Debora C; Schlindwein, Clemens

    2009-01-01

    Euglossini are typical bees of Neotropical rainforests and only a few species occur in the Caatinga. The São Francisco river, which is the only permanent river in the semi-arid NE-Brazil, is bordered by a gallery forest with evergreen leaves. This environment offers flooral rewards along the year. Surveys of euglossine bees by attracting males to scent baits showed that species of the Atlantic Rainforest like Euglossa imperialis Cockerel, E. truncata Moure and Eulaema cingulata Fabricius occur in the gallery forest of the São Francisco river under the semi-arid climate of the caatinga region. These bees are restricted to the gallery forests which function as bio-corridors, and are absent at places where the forests were cut down. This emphasizes the need to protect the threatened gallery forests to maintain biodiversity. PMID:19488520

  16. Active mode-locked lasers and other photonic devices using electro-optic whispering gallery mode resonators

    NASA Technical Reports Server (NTRS)

    Matsko, Andrey B. (Inventor); Ilchenko, Vladimir (Inventor); Savchenkov, Anatoliy (Inventor); Maleki, Lutfollah (Inventor)

    2006-01-01

    Techniques and devices using whispering gallery mode (WGM) optical resonators, where the optical materials of the WGM resonators exhibit an electro-optical effect to perform optical modulation. Examples of actively mode-locked lasers and other devices are described.

  17. Nest-Gallery Development and Caste Composition of Isolated Foraging Groups of the Drywood Termite, Incisitermes minor (Isoptera: Kalotermitidae).

    PubMed

    Himmi, S Khoirul; Yoshimura, Tsuyoshi; Yanase, Yoshiyuki; Oya, Masao; Torigoe, Toshiyuki; Akada, Masanori; Imadzu, Setsuo

    2016-01-01

    An X-ray computed-tomographic examination of nest-gallery development from timbers naturally infested by foraging groups of Incisitermes minor colonies was conducted. This study documents the colonization process of I. minor to new timbers and how the isolated groups maintain their nest-gallery system. The results suggested that development of a nest-gallery within a suitable wood item is not random, but shows selection for softer substrate and other adaptations to the different timber environments. Stigmergic coordinations were expressed in dynamic changes of the nest-gallery system; indicated by fortification behavior in sealing and re-opening a tunnel approaching the outer edge of the timber, and accumulating fecal pellets in particular chambers located beneath the timber surface. The study also examines the caste composition of isolated groups to discover how I. minor sustains colonies with and without primary reproductives. PMID:27455332

  18. Factors influencing whether children walk to school.

    PubMed

    Su, Jason G; Jerrett, Michael; McConnell, Rob; Berhane, Kiros; Dunton, Genevieve; Shankardass, Ketan; Reynolds, Kim; Chang, Roger; Wolch, Jennifer

    2013-07-01

    Few studies have simultaneously evaluated multiple levels of influence on whether children walk to school. A large cohort of 4338 subjects from 10 communities was used to identify the determinants of walking through (1) a one-level logistic regression model for individual-level variables and (2) a two-level mixed regression model for individual and school-level variables. Walking rates were positively associated with home-to-school proximity, greater age, and living in neighborhoods characterized by lower traffic density. Greater land use mix around the home was, however, associated with lower rates of walking. Rates of walking to school were also higher amongst recipients of the Free and Reduced Price Meals Program and attendees of schools with higher percentage of English language learners. Designing schools in the same neighborhood as residential districts should be an essential urban planning strategy to reduce walking distance to school. Policy interventions are needed to encourage children from higher socioeconomic status families to participate in active travel to school and to develop walking infrastructures and other measures that protect disadvantaged children. PMID:23707968

  19. A random walk approach to quantum algorithms.

    PubMed

    Kendon, Vivien M

    2006-12-15

    The development of quantum algorithms based on quantum versions of random walks is placed in the context of the emerging field of quantum computing. Constructing a suitable quantum version of a random walk is not trivial; pure quantum dynamics is deterministic, so randomness only enters during the measurement phase, i.e. when converting the quantum information into classical information. The outcome of a quantum random walk is very different from the corresponding classical random walk owing to the interference between the different possible paths. The upshot is that quantum walkers find themselves further from their starting point than a classical walker on average, and this forms the basis of a quantum speed up, which can be exploited to solve problems faster. Surprisingly, the effect of making the walk slightly less than perfectly quantum can optimize the properties of the quantum walk for algorithmic applications. Looking to the future, even with a small quantum computer available, the development of quantum walk algorithms might proceed more rapidly than it has, especially for solving real problems. PMID:17090467

  20. Factors Influencing Whether Children Walk to School

    PubMed Central

    Su, Jason G.; Jerrett, Michael; Mcconnell, Rob; Berhane, Kiros; Dunton, Genevieve; Shankardass, Ketan; Reynolds, Kim; Chang, Roger; Wolch, Jennifer

    2015-01-01

    Few studies have evaluated multiple levels of influence simultaneously on whether children walk to school. A large cohort of 4,338 subjects from ten communities was used to identify the determinants of walking through (1) a one-level logistic regression model for individual-level variables and (2) a two-level mixed regression model for individual and school-level variables. Walking rates were positively associated with home-to-school proximity, greater age, and living in neighborhoods characterized by lower traffic density. Greater land use mix around the home was, however, associated with lower rates of walking. Rates of walking to school were also higher amongst recipients of the Free and Reduced Price Meals Program and attendees of schools with higher percentage of English language learners. Designing schools in the same neighborhood as residential districts should be an essential urban planning strategy to reduce walking distance to school. Policy interventions are needed to encourage children from higher socioeconomic status families to participate in active travel to school and to develop walking infrastructures and other measures that protect disadvantaged children. PMID:23707968

  1. Walking dreams in congenital and acquired paraplegia.

    PubMed

    Saurat, Marie-Thérèse; Agbakou, Maité; Attigui, Patricia; Golmard, Jean-Louis; Arnulf, Isabelle

    2011-12-01

    To test if dreams contain remote or never-experienced motor skills, we collected during 6 weeks dream reports from 15 paraplegics and 15 healthy subjects. In 9/10 subjects with spinal cord injury and in 5/5 with congenital paraplegia, voluntary leg movements were reported during dream, including feelings of walking (46%), running (8.6%), dancing (8%), standing up (6.3%), bicycling (6.3%), and practicing sports (skiing, playing basketball, swimming). Paraplegia patients experienced walking dreams (38.2%) just as often as controls (28.7%). There was no correlation between the frequency of walking dreams and the duration of paraplegia. In contrast, patients were rarely paraplegic in dreams. Subjects who had never walked or stopped walking 4-64 years prior to this study still experience walking in their dreams, suggesting that a cerebral walking program, either genetic or more probably developed via mirror neurons (activated when observing others performing an action) is reactivated during sleep. PMID:21704532

  2. Beam walking can detect differences in walking balance proficiency across a range of sensorimotor abilities.

    PubMed

    Sawers, Andrew; Ting, Lena H

    2015-02-01

    The ability to quantify differences in walking balance proficiency is critical to curbing the rising health and financial costs of falls. Current laboratory-based approaches typically focus on successful recovery of balance while clinical instruments often pose little difficulty for all but the most impaired patients. Rarely do they test motor behaviors of sufficient difficulty to evoke failures in balance control limiting their ability to quantify balance proficiency. Our objective was to test whether a simple beam-walking task could quantify differences in walking balance proficiency across a range of sensorimotor abilities. Ten experts, ten novices, and five individuals with transtibial limb loss performed six walking trials across three different width beams. Walking balance proficiency was quantified as the ratio of distance walked to total possible distance. Balance proficiency was not significantly different between cohorts on the wide-beam, but clear differences between cohorts on the mid and narrow-beams were identified. Experts walked a greater distance than novices on the mid-beam (average of 3.63±0.04m verus 2.70±0.21m out of 3.66m; p=0.009), and novices walked further than amputees (1.52±0.20m; p=0.03). Amputees were unable to walk on the narrow-beam, while experts walked further (3.07±0.14m) than novices (1.55±0.26m; p=0.0005). A simple beam-walking task and an easily collected measure of distance traveled detected differences in walking balance proficiency across sensorimotor abilities. This approach provides a means to safely study and evaluate successes and failures in walking balance in the clinic or lab. It may prove useful in identifying mechanisms underlying falls versus fall recoveries. PMID:25648493

  3. Living in the question.

    PubMed

    Flower, J

    1999-01-01

    We live in a fast moving-world. Business has accelerated to breathtaking speeds in the 1990s--and in the last few years the afterburner has really kicked in. The speed of change is overwhelming. Especially in health care, who has time to "live in the question?" We need to decide things quickly, get the decision out of the way, and move on, right? Maybe. Biology shows us that you can't plan ahead very far. New things come along that you don't even have a category for, and therefore you don't even see them. Things are going to happen that you literally have no notion are even possible. The key to succeeding in this environment? Don't plan ahead. Stay curious. Make small bets. Build organizational hothouses. Feed the seedlings that grow. The challenge is to remain curious, to live in the question, both personally and organizationally. PMID:10557490

  4. Knowledge based question answering

    SciTech Connect

    Pazzani, M.J.; Engelman, C.

    1983-01-01

    The natural language database query system incorporated in the Knobs Interactive Planning System comprises a dictionary driven parser, APE-II, and script interpreter whch yield a conceptual dependency as a representation of the meaning of user input. A conceptualisation pattern matching production system then determines and executes a procedure for extracting the desired information from the database. In contrast to syntax driven q-a systems, e.g. those based on atn parsers, APE-II is driven bottom-up by expectations associated with word meanings. The goals of this approach include utilising similar representations for questions with similar meanings but widely varying surface structures, developing a powerful mechanism for the disambiguation of words with multiple meanings and the determination of pronoun referents, answering questions which require inferences to be understood, and interpreting ellipses and ungrammatical statements. The Knobs demonstration system is an experimental, expert system for air force mission planning applications. 16 refs.

  5. Decoherence can be useful in quantum walks

    SciTech Connect

    Kendon, Viv; Tregenna, Ben

    2003-04-01

    We present a study of the effects of decoherence in the operation of a discrete quantum walk on a line, cycle, and hypercube. We find high sensitivity to decoherence, increasing with the number of steps in the walk, as the particle is becoming more delocalized with each step. However, the effect of a small amount of decoherence is to enhance the properties of the quantum walk that are desirable for the development of quantum algorithms. Specifically, we observe a highly uniform distribution on the line, a very fast mixing time on the cycle, and more reliable hitting times across the hypercube.

  6. Quantum walk public-key cryptographic system

    NASA Astrophysics Data System (ADS)

    Vlachou, C.; Rodrigues, J.; Mateus, P.; Paunković, N.; Souto, A.

    2015-12-01

    Quantum Cryptography is a rapidly developing field of research that benefits from the properties of Quantum Mechanics in performing cryptographic tasks. Quantum walks are a powerful model for quantum computation and very promising for quantum information processing. In this paper, we present a quantum public-key cryptographic system based on quantum walks. In particular, in the proposed protocol the public-key is given by a quantum state generated by performing a quantum walk. We show that the protocol is secure and analyze the complexity of public key generation and encryption/decryption procedures.

  7. [Walking assist robot and its clinical application].

    PubMed

    Kakou, Hiroaki; Shitama, Hideo; Kimura, Yoshiko; Nakamoto, Yoko; Furuta, Nami; Honda, Kanae; Wada, Futoshi; Hachisuka, Kenji

    2009-06-01

    The walking assist robot was developed to improve gait disturbance in patients with severe disabilities. The robot had a trunk supporter, power generator and operating arms which held patient's lower extremities and simulated walking, a control unit, biofeedback system, and a treadmill. We applied the robot-aided gait training to three patients with severe gait disturbance induced by stroke, axonal Guillan-Barré syndrome or spinal cord injury, and the walking assist robot turned out to be effective in improving the gait disturbance. PMID:19530565

  8. An experimental analysis of human straight walking

    NASA Astrophysics Data System (ADS)

    Li, Tao; Ceccarelli, Marco

    2013-03-01

    In this paper, an experimental analysis of human straight walking has been presented. Experiments on human walking were carried out by using Cassino tracking system which is a passive cable-based measuring system. This system is adopted because it is capable of both pose and wrench measurements with fairly simple monitoring of operation. By using experimental results, trajectories of a human limb extremity and its posture have been analyzed; forces that are exerted against cables by the limb of a person under test have been measured by force sensors as well. Furthermore, by using experimental tests, modeling and characterization of the human straight walking gait have been proposed.

  9. Universal computation by multiparticle quantum walk.

    PubMed

    Childs, Andrew M; Gosset, David; Webb, Zak

    2013-02-15

    A quantum walk is a time-homogeneous quantum-mechanical process on a graph defined by analogy to classical random walk. The quantum walker is a particle that moves from a given vertex to adjacent vertices in quantum superposition. We consider a generalization to interacting systems with more than one walker, such as the Bose-Hubbard model and systems of fermions or distinguishable particles with nearest-neighbor interactions, and show that multiparticle quantum walk is capable of universal quantum computation. Our construction could, in principle, be used as an architecture for building a scalable quantum computer with no need for time-dependent control. PMID:23413349

  10. From the galleries to the clinic: applying art museum lessons to patient care.

    PubMed

    Miller, Alexa; Grohe, Michelle; Khoshbin, Shahram; Katz, Joel T

    2013-12-01

    Increasingly, medical educators integrate art-viewing into curricular interventions that teach clinical observation-often with local art museum educators. How can cross-disciplinary collaborators explicitly connect the skills learned in the art museum with those used at the bedside? One approach is for educators to align their pedagogical approach using similar teaching methods in the separate contexts of the galleries and the clinic. We describe two linked pedagogical exercises--Visual Thinking Strategies (VTS) in the museum galleries and observation at the bedside--from "Training the Eye: Improving the Art of Physical Diagnosis," an elective museum-based course at Harvard Medical School. It is our opinion that while strategic interactions with the visual arts can improve skills, it is essential for students to apply them in a clinical context with faculty support-requiring educators across disciplines to learn from one another. PMID:24014232

  11. Hybrid whispering gallery mode/plasmonic chain ring resonators for biosensing

    NASA Astrophysics Data System (ADS)

    Arbabi, Ehsan; Kamali, Seyedeh Mahsa; Arnold, Stephen; Goddard, Lynford L.

    2014-12-01

    We analyze the physics of hybrid whispering gallery mode resonators formed by arranging a periodic array of epitopes (i.e., gold nano-shells covering silica nano-spheres) around the equator of a silica microsphere. When the epitopes are located at the antinodes of the field of the whispering gallery mode, we find that the field localization properties near the epitopes change drastically as the radius of the epitopes is varied due to the existence of distinct coupling regions of the hybrid resonator. We investigated the application of such resonators for biosensing by calculating the resonance wavelength shift caused by a binding event of a single Thyroglobulin cancer marker protein to the surface of an epitope in the chain.

  12. In-fiber whispering-gallery-mode resonator fabricated by femtosecond laser micromachining.

    PubMed

    Shi, Leilei; Zhu, Tao; Huang, Dongmei; Liu, Min; Deng, Ming; Huang, Wei

    2015-08-15

    An in-fiber whispering-gallery-mode resonator fabricated by femtosecond laser micromachining is demonstrated. The cylinder resonator cavity is fabricated by scanning the D-fiber cladding with infrared femtosecond pulses along a cylindrical trace with a radius of 25 μm and height of 20 μm. Quality factor on the order of 10(3) is achieved by smoothing the cavity surface with an ultrasonic cleaner, which is mainly limited by the surface roughness of several hundred nanometers. Resonant characteristics and polarization dependence of the proposed resonator are also studied in detail. Our method takes a step forward in the integration of whispering-gallery-mode resonators. PMID:26274656

  13. White-Light Whispering Gallery Mode Optical Resonator System and Method

    NASA Technical Reports Server (NTRS)

    Matsko, Andrey B. (Inventor); Savchenkov, Anatoliy A. (Inventor); Maleki, Lute (Inventor)

    2009-01-01

    An optical resonator system and method that includes a whispering-gallery mode (WGM) optical resonator that is capable of resonating across a broad, continuous swath of frequencies is provided. The optical resonator of the system is shaped to support at least one whispering gallery mode and includes a top surface, a bottom surface, a side wall, and a first curved transition region extending between the side wall and the top surface. The system further includes a coupler having a coupling surface which is arranged to face the transition region of the optical resonator and in the vicinity thereof such that an evanescent field emitted from the coupler is capable of being coupled into the optical resonator through the first curved transition region

  14. Naturally Phase-Matched Second-Harmonic Generation in a Whispering-Gallery-Mode Resonator

    NASA Astrophysics Data System (ADS)

    Fürst, J. U.; Strekalov, D. V.; Elser, D.; Lassen, M.; Andersen, U. L.; Marquardt, C.; Leuchs, G.

    2010-04-01

    We demonstrate for the first time natural phase matching for optical frequency doubling in a high-Q whispering-gallery-mode resonator made of lithium niobate. A conversion efficiency of 9% is achieved at 30μW in-coupled continuous wave pump power. The observed saturation pump power of 3.2 mW is almost 2 orders of magnitude lower than the state-of-the-art value. This suggests an application of our frequency doubler as a source of nonclassical light requiring only a low-power pump, which easily can be quantum noise limited. Our theoretical analysis of the three-wave mixing in a whispering-gallery-mode resonator provides the relative conversion efficiencies for frequency doubling in various modes.

  15. High gain selective amplification in whispering gallery mode resonators: analysis by cavity ring down method

    NASA Astrophysics Data System (ADS)

    Féron, P.; Rasoloniaina, A.; Huet, V.; Le Cren, E.; Trebaol, S.; Nunzi Conti, G.; Serier-Brault, H.; Mortier, M.; Dumeige, Y.

    2013-03-01

    We study both theoretically and experimentally the dispersive properties of single whispering gallery mode resonators. We present a simple experimental protocol which allows us to obtain in detail its coupling regime and thus their dispersive properties. We demonstrate a compact optical amplifier with a gain up to 20dB in an Erbium doped fluoride microsphere of 135μm in diameter coupled via a tapered fiber. The model is also applied to analyze the dynamic behavior of the modal coupling between two degenerate resonances of the same cavity. In particular, this can be used to describe the coupling of counterpropagating whispering gallery modes (WGM) by Rayleigh scattering. The theory is successfully compared to experiments carried out in silica microspheres

  16. Physics. Creating and probing electron whispering-gallery modes in graphene.

    PubMed

    Zhao, Yue; Wyrick, Jonathan; Natterer, Fabian D; Rodriguez-Nieva, Joaquin F; Lewandowski, Cyprian; Watanabe, Kenji; Taniguchi, Takashi; Levitov, Leonid S; Zhitenev, Nikolai B; Stroscio, Joseph A

    2015-05-01

    The design of high-finesse resonant cavities for electronic waves faces challenges due to short electron coherence lengths in solids. Complementing previous approaches to confine electronic waves by carefully positioned adatoms at clean metallic surfaces, we demonstrate an approach inspired by the peculiar acoustic phenomena in whispering galleries. Taking advantage of graphene's gate-tunable light-like carriers, we create whispering-gallery mode (WGM) resonators defined by circular pn junctions, induced by a scanning tunneling probe. We can tune the resonator size and the carrier concentration under the probe in a back-gated graphene device over a wide range. The WGM-type confinement and associated resonances are a new addition to the quantum electron-optics toolbox, paving the way to develop electronic lenses and resonators. PMID:25954005

  17. Neutrino Oscillations:. Hierarchy Question

    NASA Astrophysics Data System (ADS)

    Ernst, D. J.; Cogswell, B. K.; Burroughs, H. R.; Escamilla-Roa, J.; Latimer, D. L.

    2014-09-01

    The only experimentally observed phenomenon that lies outside the standard model of the electroweak interaction is neutrino oscillations. A way to try to unify the extensive neutrino oscillation data is to add a phenomenological mass term to the Lagrangian that is not diagonal in the flavor basis. The goal is then to understand the world's data in terms of the parameters of the mixing matrix and the differences between the squares of the masses of the neutrinos. An outstanding question is what is the correct ordering of the masses, the hierarchy question. We point out a broken symmetry relevant to this question, the symmetry of the simultaneous interchange of hierarchy and the sign of θ13. We first present the results of an analysis of data that well determine the phenomenological parameters but are not sensitive to the hierarchy. We find θ13 = 0.152±0.014, θ 23 = 0.25{ - 0.05}{ + 0.03} π and Δ32 = 2.45±0.14×10-3 eV2, results consistent with others. We then include data that are sensitive to the hierarchy and the sign of θ13. We find, unlike others, four isolated minimum in the χ2-space as predicted by the symmetry. Now that Daya Bay and RENO have determined θ13 to be surprisingly large, the Super-K atmospheric data produce meaningful symmetry breaking such that the inverse hierarchy is preferred at the 97.2 % level.

  18. Questioning Many Mysteries

    NASA Astrophysics Data System (ADS)

    Martin, Sara F.

    2015-04-01

    The first section of this memoir queries my formative years. Indirectly I address the question, did my childhood and early years make a difference in my choice of career? Why and how did I begin my journey to becoming a scientist? Did I choose the field of solar astronomy or did circumstances dictate it for me? In the second section, I travel through my work environments and experiences, talking about interactions and aspects of being a scientist that do not appear in our research papers. What parts of my research were happenstances and what parts did I plan? What does it feel like to be on scientific quests? Using examples in my journey, I also turn to questions that have intrigued me throughout my sojourn as a solar astronomer. How do scientific discoveries come about? What factors lead to little discoveries? And what factors lead to major exciting discoveries? Are there timely questions we do not think to ask? How can small, seemingly scattered pieces of knowledge suddenly coalesce into a deeper understanding - what is called the "Aha!" experience - the times when our mental light switches on, and with child-like wonder we behold a "big picture"?

  19. Shooting Gallery Attendance among IDUs in Tijuana and Ciudad Juarez, Mexico: Correlates, Prevention Opportunities, and the Role of the Environment

    PubMed Central

    Philbin, Morgan; Pollini, Robin A.; Ramos, Rebecca; Lozada, Remedios; Brouwer, Kimberly C.; Ramos, Maria Elena; Firestone-Cruz, Michelle; Case, Patricia; Strathdee, Steffanie A.

    2009-01-01

    We identified factors associated with shooting gallery attendance among injection drug users (IDUs) in two Mexico–US border cities. IDUs in Tijuana (n = 222) and Ciudad Juarez (n = 205), Mexico, who were ≥18 years and injected illicit drugs in the last month were recruited using respondent-driven sampling (RDS). An interviewer-administered survey collected sociodemographic and behavioral data. Logistic regression was used to examine correlates of shooting gallery attendance in each of the two cities. Homelessness and being arrested for syringe possession—both structural level factors—were associated with shooting gallery use in both cities. In Ciudad Juarez, younger age and having overdosed were also associated with shooting gallery use. Our study highlights the need for structural interventions that mitigate homelessness among IDUs and facilitate changes in law enforcement practices associated with shooting gallery use. Harm reduction interventions based within shooting galleries should also be considered to prevent transmission of blood-borne pathogens among IDUs. PMID:18369723

  20. High Point Walking for Health: Creating Built and Social Environments That Support Walking in a Public Housing Community

    PubMed Central

    Rabkin, Janice; Sharify, Denise; Song, Lin

    2009-01-01

    Objectives. We implemented and evaluated multiple interventions to increase walking activity at a multicultural public housing site. Methods. A community-based participatory research partnership and community action teams assessed assets and barriers related to walking and developed multiple interventions to promote walking activity. Interventions included sponsoring walking groups, improving walking routes, providing information about walking options, and advocating for pedestrian safety. A pre–post study design was used to assess the changes in walking activity. Results. Self-reported walking activity increased among walking group participants from 65 to 109 minutes per day (P = .001). The proportion that reported being at least moderately active for at least 150 minutes per week increased from 62% to 81% (P = .018). Conclusions. A multicomponent intervention developed through participatory research methods that emphasized walking groups and included additional strategies to change the built and social environments increased walking activity at a public housing site in Seattle. PMID:19890163

  1. A&M. TAN607. Interior view of operating gallery in hot shop. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    A&M. TAN-607. Interior view of operating gallery in hot shop. Shielded viewing windows are along right side of corridor. Cabinet on wheels at left of corridor is operating console for hot shop manipulators. When in use, it is stationed at window station and connected to appropriate control cables. note reserve bottles of zinc bromide above each station. Date: January 3, 1955. INEEL negative no. 55-0072 - Idaho National Engineering Laboratory, Test Area North, Scoville, Butte County, ID

  2. Semiochemical emission from individual galleries of the southern pine beetle, (Coleoptera: Curculionidae: Scolytinae), attacking standing trees.

    PubMed

    Pureswaran, Deepa S; Sullivan, Brian T

    2012-02-01

    We collected, identified, and quantified volatiles arising from individual gallery entrances of the monogamous bark beetle Dendroctonus frontalis Zimmermann. Samples were collected while the insects were mass attacking mature loblolly pines (Pinus taeda L.) in an established infestation in western Mississippi, 1 August through 3 October 2005. Following volatile sample collection, the entrances were dissected and categorized according to those that 1) contained a solitary female (the gallery initiating sex), 2) contained a pair that had not yet produced an egg gallery, 3) led to an egg gallery with niches and/or eggs, or 4) represented failed attacks (either abandoned or containing dead beetles). The greatest mean release rate of the female-produced aggregation pheromone components frontalin (74 ng/h) and trans-verbenol (0.35 microg/h) was detected from entrances of solitary females, whereas the highest mean quantities of the male-produced multifunctional pheromone components endo-brevicomin (18 ng/h) and verbenone (0.15 microg/h) were detected from entrances of preoviposition beetle pairs. Alpha-pinene, a host-produced monoterpene that functions as a synergist for the aggregation attractant for D. frontalis, was detected from entrances of solitary females and preoviposition pairs at a rate of 0.6 mg/h, or 3-4 orders of magnitude greater than the insect-produced components of the attractant. Our results indicate that the release rates of pheromone components used in published field studies of the chemical ecology of D. frontalis (generally > 0.1 mg/h) represent thousands of 'attack equivalents' or production rates on the scale of a beetle mass attack on a single host. Additionally, our data suggest that the loss in attractiveness of host tissue fully colonized by D. frontalis is because of the disappearance of attractants rather than an increase in inhibitors. PMID:22420266

  3. Coherences of transmon qubits embedded in superconducting whispering gallery mode resonators

    NASA Astrophysics Data System (ADS)

    Minev, Z. K.; Serniak, K.; Pop, Ioan; Leghtas, Z.; Sliwa, K.; Frunzio, L.; Schoelkopf, R.; Devoret, Michel

    2015-03-01

    We describe the design and measurement of a planar uperconducting two-resonator one-qubit device. The two resonators are realized in a hardware-efficient way by the differential modes of a superconducting whispering gallery mode resonator [APL 103, 142604]. This device forms an integrated basis for a quantum memory [New J. Phys. 16, 045014 2014]. Work supported by: IARPA, ARO, and ONR.

  4. Whispering-gallery-mode analysis of phase-matched doubly resonant second-harmonic generation

    NASA Astrophysics Data System (ADS)

    Dumeige, Yannick; Féron, Patrice

    2006-12-01

    We propose a coupled modes analysis of second-harmonic generation in microdisk resonators. We demonstrate that whispering gallery modes can be used to obtain a combination of modal and geometrical quasi-phase-matching (without domain inversion) to obtain efficient conversion in isotropic and nonferroelectric materials such as III-V semiconductor compounds. Finally we use an analytical model to describe the coupling between a bus waveguide and the nonlinear microdisk to achieve an optimization scheme for practical configuration.

  5. Coupled-mode induced transparency in a bottle whispering-gallery-mode resonator.

    PubMed

    Wang, Yue; Zhang, Kun; Zhou, Song; Wu, Yi-Hui; Chi, Ming-Bo; Hao, Peng

    2016-04-15

    Whispering-gallery-mode (WGM) optical resonators are ideal systems for achieving electromagnetically induced transparency-like phenomenon. Here, we experimentally demonstrate that one or more transparent windows can be achieved with coupled-mode induced transparency (CMIT) in a single bottle WGM resonator due to the bottle's dense mode spectra and tunable resonant frequencies. This device offers an approach for multi-channel all-optical switching devices and sensitivity-enhanced WGM-based sensors. PMID:27082355

  6. Thermal characterisation of (bio)polymers with a temperature-stabilised whispering gallery mode microsensor

    NASA Astrophysics Data System (ADS)

    Kim, Eugene; Foreman, Matthew R.; Baaske, Martin D.; Vollmer, Frank

    2015-04-01

    In this work, we theoretically and experimentally investigate the thermal response of whispering gallery mode microresonators operating in an aqueous glycerol medium. Thermal stabilisation of the resonance wavelength is realised by appropriate choice of the resonator radius and glycerol concentration, with a 60 fold reduction in thermal sensitivity demonstrated. Finally, we employ our stabilised system to determine the thermal dependence of the molecular polarisability of adsorbed bovine serum albumin molecules and the refractive index of dextran and poly(diallyldimethylammonium chloride) coatings.

  7. Dynamic Fano-like resonances in erbium-doped whispering-gallery-mode microresonators

    SciTech Connect

    Lei, Fuchuan; Peng, Bo; Özdemir, Şahin Kaya Yang, Lan; Long, Gui Lu

    2014-09-08

    We report Fano-like asymmetric resonances modulated by optical gain in a whispering-gallery-mode resonator fabricated from erbium-doped silica. A time-dependent gain profile leads to dynamically varying sharp asymmetric resonances with features similar to Fano resonances. Depending on the scan speed of the frequency of the probe laser and the pump-probe power ratio, transmission spectra of the active microcavity exhibit a resonance dip, a resonance peak, or a Fano-like resonance.

  8. Tunability and synthetic lineshapes in high-Q optical whispering gallery modes

    NASA Technical Reports Server (NTRS)

    Ilchenko, Vladimir S.; Savchenkov, Anatoliy A.; Matsko, Andrey B.; Maleki, Lute

    2003-01-01

    We demonstrate novel techniques to manipulate spectral properties of high quality factor (Q>107) whispering-gallery modes (WGM) in optical dielectric microresonators. These include permanent frequency trimming of WGM frequencies by means of UV photosensitivity of germanium doped silica resonators electro-optical tuning of WGM in lithium niobate resonators, and cascading of microresonators for obtaining second-order filtering function. We present theoretical interpretation of experimental results, and application example of techniques for photonic microwave filtering.

  9. Silica hollow bottle resonators for use as whispering gallery mode based chemical sensors

    NASA Astrophysics Data System (ADS)

    Stoian, Razvan-Ionut; Bui, Khoa V.; Rosenberger, A. T.

    2015-12-01

    A simple three-step method for making silica hollow bottle resonators (HBRs) was developed. This procedure is advantageous because it uses commercially available materials, is cost effective, and is easy to implement. Additionally, the use of these HBRs as whispering gallery mode based chemical sensors is demonstrated by preliminary absorption sensing results in the near infrared (1580-1660 nm) using a trace gas (CH4) in air at atmospheric pressure and a dye (SDA2072) in methanol solution.

  10. Brillouin lasing with a CaF2 whispering gallery mode resonator.

    PubMed

    Grudinin, Ivan S; Matsko, Andrey B; Maleki, Lute

    2009-01-30

    Stimulated Brillouin scattering with both pump and Stokes beams in resonance with whispering gallery modes of an ultrahigh Q calcium fluoride resonator is demonstrated for the first time. The resonator is pumped with 1064 nm light and has 3 muW Brillouin lasing threshold. The scattering is observed due to the unique morphology of the resonator reducing the phase mismatch between the optical modes and the hypersound wave. PMID:19257418

  11. Mussels realize Weierstrassian Lévy walks as composite correlated random walks

    PubMed Central

    Reynolds, Andy M.

    2014-01-01

    Composite correlated random walks (CCRW) have been posited as a potential replacement for Lévy walks and it has also been suggested that CCRWs have been mistaken for Lévy walks. Here I test an alternative, emerging hypothesis: namely that some organisms approximate Lévy walks as an innate CCRW. It is shown that the tri-modal CCRW found to describe accurately the movement patterns of mussels (Mytilus edulis) during spatial pattern formation in mussel beds can be regarded as being the first three levels in a hierarchy of nested movement patterns which if extended indefinitely would correspond to a Lévy walk whose characteristic (power-law) exponent is tuned to nearly minimize the time required to form patterned beds. The mussels realise this Lévy walk to good approximation across a biologically meaningful range of scales. This demonstrates that the CCRW not only describes mussel movement patterns, it explains them. PMID:24637423

  12. High Contribution of Gallery Forests to Local Evaporation in Semi-Arid Burkina Faso

    NASA Astrophysics Data System (ADS)

    Ceperley, N. C.; Mande, T.; Tyler, S. W.; Van De Giesen, N.; Rinaldo, A.; Parlange, M. B.

    2014-12-01

    Management of the hydrologic cycle is critical to the primary livelihood of a large part of semi-arid West Africa's primary livelihood, rain-fed farming. We use flux measurements from an eddy-covariance station coupled with a dense network of small wireless meteorological stations to examine the relationship between land surface properties (albedo, soil moisture, and roughness) and evapotranspiration in a small (3.5 km2) catchment in Burkina Faso, West Africa. The catchment is a matrix of savanna and agricultural land maintained under various regimes, providing a comparison of multiple land use types of Sudanian Wooded Savanna including a canyon gallery forest, agroforestry parklands, occasionally grazed semi-open savanna, a semi-closed wooded slope, fallow fields, rice paddies, and ephemeral wetlands. By filtering out times when dry air was entrained, we demonstrate the small control of soil moisture and vegetation on the evaporative fraction, which was not initially visible. Additionally we document the high contribution of the gallery forest to the the catchment evaporation, despite its small size. These small meteorological stations could be paired with currently available satellite data to calculate evaporation over a much larger area, even when eddy-covariance equipment is not available. These findings reinforce local cultural beliefs of the importance of gallery forests for climate regulation and may provide tools to key local decision makers, rural farmers.

  13. Do isolated gallery-forest trees facilitate recruitment of forest seedlings and saplings in savannna?

    NASA Astrophysics Data System (ADS)

    Azihou, Akomian Fortuné; Glèlè Kakaï, Romain; Sinsin, Brice

    2013-11-01

    Facilitation is an ecological process that allows some species to establish in environments they can hardly afford in the absence of the process. This study investigated if the subcanopy of gallery-forest trees isolated in savanna is suitable for the early recruitment of forest woody species. We measured tree crown area as well as the density of seedlings and saplings of gallery-forest tree species beneath isolated trees and in the savanna matrix along 50 transects of 5-km long and 600 m wide located along four gallery forests. We then tested the nurse-plant effect and Janzen-Connell hypothesis beneath isolated trees. We also examined the relationships between the crown area and the density of seedlings and saplings. Among the eight identified tree species isolated in savanna, only Daniellia oliveri and Khaya senegalensis showed nurse-plant effect and promoted a significant, yet low early recruitment with a seedling-to-sapling survival of 0.044 and 0.578, respectively. The suitability of the subcanopy of isolated trees decreased with the recruitment progression and Janzen-Connell effects were absent. Seedlings had neutral association with the crown area of isolated trees which shifted to positive at the sapling stage. The species of the isolated tree and the crown area explained less than 20% of total variance, indicating that other predictive factors are important in explaining the nurse-plant effect observed in this study.

  14. Kinematic Responses to Changes in Walking Orientation and Gravitational Load in Drosophila melanogaster

    PubMed Central

    Mendes, César S.; Rajendren, Soumya V.; Bartos, Imre; Márka, Szabolcs; Mann, Richard S.

    2014-01-01

    Walking behavior is context-dependent, resulting from the integration of internal and external influences by specialized motor and pre-motor centers. Neuronal programs must be sufficiently flexible to the locomotive challenges inherent in different environments. Although insect studies have contributed substantially to the identification of the components and rules that determine locomotion, we still lack an understanding of how multi-jointed walking insects respond to changes in walking orientation and direction and strength of the gravitational force. In order to answer these questions we measured with high temporal and spatial resolution the kinematic properties of untethered Drosophila during inverted and vertical walking. In addition, we also examined the kinematic responses to increases in gravitational load. We find that animals are capable of shifting their step, spatial and inter-leg parameters in order to cope with more challenging walking conditions. For example, flies walking in an inverted orientation decreased the duration of their swing phase leading to increased contact with the substrate and, as a result, greater stability. We also find that when flies carry additional weight, thereby increasing their gravitational load, some changes in step parameters vary over time, providing evidence for adaptation. However, above a threshold that is between 1 and 2 times their body weight flies display locomotion parameters that suggest they are no longer capable of walking in a coordinated manner. Finally, we find that functional chordotonal organs are required for flies to cope with additional weight, as animals deficient in these proprioceptors display increased sensitivity to load bearing as well as other locomotive defects. PMID:25350743

  15. The role of vision in odor-plume tracking by walking and flying insects.

    PubMed

    Willis, Mark A; Avondet, Jennifer L; Zheng, Elizabeth

    2011-12-15

    The walking paths of male cockroaches, Periplaneta americana, tracking point-source plumes of female pheromone often appear similar in structure to those observed from flying male moths. Flying moths use visual-flow-field feedback of their movements to control steering and speed over the ground and to detect the wind speed and direction while tracking plumes of odors. Walking insects are also known to use flow field cues to steer their trajectories. Can the upwind steering we observe in plume-tracking walking male cockroaches be explained by visual-flow-field feedback, as in flying moths? To answer this question, we experimentally occluded the compound eyes and ocelli of virgin P. americana males, separately and in combination, and challenged them with different wind and odor environments in our laboratory wind tunnel. They were observed responding to: (1) still air and no odor, (2) wind and no odor, (3) a wind-borne point-source pheromone plume and (4) a wide pheromone plume in wind. If walking cockroaches require visual cues to control their steering with respect to their environment, we would expect their tracks to be less directed and more variable if they cannot see. Instead, we found few statistically significant differences among behaviors exhibited by intact control cockroaches or those with their eyes occluded, under any of our environmental conditions. Working towards our goal of a comprehensive understanding of chemo-orientation in insects, we then challenged flying and walking male moths to track pheromone plumes with and without visual feedback. Neither walking nor flying moths performed as well as walking cockroaches when there was no visual information available. PMID:22116754

  16. Nordic Walking Practice Might Improve Plantar Pressure Distribution

    ERIC Educational Resources Information Center

    Perez-Soriano, Pedro; Llana-Belloch, Salvador; Martinez-Nova, Alfonso; Morey-Klapsing, G.; Encarnacion-Martinez, Alberto

    2011-01-01

    Nordic walking (NW), characterized by the use of two walking poles, is becoming increasingly popular (Morgulec-Adamowicz, Marszalek, & Jagustyn, 2011). We studied walking pressure patterns of 20 experienced and 30 beginner Nordic walkers. Plantar pressures from nine foot zones were measured during trials performed at two walking speeds (preferred…

  17. Walking after Stroke: Comfortable versus Maximum Safe Speed.

    ERIC Educational Resources Information Center

    Bohannon, Richard W.

    1992-01-01

    This study attempted to (1) determine whether stroke patients (n=20) can safely increase their walking speed above that of comfortable walking; (2) describe the relationship between comfortable and maximum safe walking speed; and (3) examine correlations between maximum and comfortable speeds and a functional walking score. Subjects were able to…

  18. Walking and Eating Behavior of Toddlers at 12 Months Old

    ERIC Educational Resources Information Center

    Koda, Naoko; Akimoto, Yuko; Hirose, Toshiya; Hinobayashi, Toshihiko; Minami, Tetsuhiro

    2004-01-01

    Locomotive and eating behavior of 52 toddlers was observed at 12 months old in a nursery school and investigated in relation to the acquisition of independent walking. The toddlers who acquired walking ate more by themselves using the hands than the toddlers who did not start walking. This suggested that acquisition of walking was associated with…

  19. To Question or Not to Question: That Seems to Be the Question.

    ERIC Educational Resources Information Center

    Bradtmueller, Weldon G.; Egan, James B.

    Research on the effects of questioning in the classroom has explored the placement, timing, type, and social impact of questions. Principles of good questioning include the following: (1) well-stated questions should be concise, clear, and complete; (2) questions should be topical in nature, requiring a complex answer; (3) yes or no questions…

  20. Epidemic spreading driven by biased random walks

    NASA Astrophysics Data System (ADS)

    Pu, Cunlai; Li, Siyuan; Yang, Jian

    2015-08-01

    Random walk is one of the basic mechanisms of many network-related applications. In this paper, we study the dynamics of epidemic spreading driven by biased random walks in complex networks. In our epidemic model, infected nodes send out infection packets by biased random walks to their neighbor nodes, and this causes the infection of susceptible nodes that receive the packets. Infected nodes recover from the infection at a constant rate λ, and will not be infected again after recovery. We obtain the largest instantaneous number of infected nodes and the largest number of ever-infected nodes respectively, by tuning the parameter α of the biased random walks. Simulation results on model and real-world networks show that spread of the epidemic becomes intense and widespread with increase of either delivery capacity of infected nodes, average node degree, or homogeneity of node degree distribution.

  1. Steering random walks with kicked ultracold atoms

    NASA Astrophysics Data System (ADS)

    Weiß, Marcel; Groiseau, Caspar; Lam, W. K.; Burioni, Raffaella; Vezzani, Alessandro; Summy, Gil S.; Wimberger, Sandro

    2015-09-01

    The kicking sequence of the atom-optics kicked rotor at quantum resonance can be interpreted as a quantum random walk in momentum space. We show how such a walk can become the basis for nontrivial classical walks by applying a random sequence of intensities and phases of the kicking lattice chosen according to a probability distribution. This distribution converts on average into the final momentum distribution of the kicked atoms. In particular, it is shown that a power-law distribution for the kicking strengths results in a Lévy walk in momentum space and in a power law with the same exponent in the averaged momentum distribution. Furthermore, we investigate the stability of our predictions in the context of a realistic experiment with Bose-Einstein condensates.

  2. 'Walking Meetings' May Boost Employee Health, Productivity

    MedlinePlus

    ... FRIDAY, July 22, 2016 (HealthDay News) -- Here's an idea that might make staff meetings less boring and more healthful: New research suggests you walk while you talk business. The small study found that converting a single ...

  3. Measuring Oscillating Walking Paths with a LIDAR

    PubMed Central

    Teixidó, Mercè; Pallejà, Tomàs; Tresanchez, Marcel; Nogués, Miquel; Palacín, Jordi

    2011-01-01

    This work describes the analysis of different walking paths registered using a Light Detection And Ranging (LIDAR) laser range sensor in order to measure oscillating trajectories during unsupervised walking. The estimate of the gait and trajectory parameters were obtained with a terrestrial LIDAR placed 100 mm above the ground with the scanning plane parallel to the floor to measure the trajectory of the legs without attaching any markers or modifying the floor. Three different large walking experiments were performed to test the proposed measurement system with straight and oscillating trajectories. The main advantages of the proposed system are the possibility to measure several steps and obtain average gait parameters and the minimum infrastructure required. This measurement system enables the development of new ambulatory applications based on the analysis of the gait and the trajectory during a walk. PMID:22163891

  4. Database of Standardized Questionnaires About Walking & Bicycling

    Cancer.gov

    This database contains questionnaire items and a list of validation studies for standardized items related to walking and biking. The items come from multiple national and international physical activity questionnaires.

  5. Parent Safety Perceptions of Child Walking Routes

    PubMed Central

    Boles, Shawn; Johnson-Shelton, Deb; Schlossberg, Marc; Richey, David

    2014-01-01

    Walking rates to school remain low for U.S. children in large part due to parent concern for child safety. Little research has investigated the specific features of streets and intersection networks that parents associate with safe walking networks for children. To investigate which aspects of the child walking environment lead to parental concern, parent volunteers conducted an audit of streets leading to seven elementary schools in a suburban school district. Parents were most likely to feel concern about streets that lacked sidewalks or had sidewalks with obstructions. Wheelchair-accessible routes were seen as appropriate for walking children. Parents expressed concern over safety at intersections, particularly those involving large streets; traffic controls did not mollify their concern. PMID:25664239

  6. Walking (Gait), Balance, and Coordination Problems

    MedlinePlus

    ... tizanidine are generally effective in treating this symptom. Balance : Balance problems typically result in a swaying and “drunken” ... factors for falls are complex and include: poor balance and slowed walking reduced proprioception (the sensation of ...

  7. Care and Operation of Walk-Ins.

    ERIC Educational Resources Information Center

    Bauer, James M.

    1979-01-01

    Problems of owners who use their walk-in coolers and freezers only part of the year demand special consideration. Proper techniques for startup, operation, and shutdown must be used to guarantee efficient, inexpensive operation. (Author)

  8. Energy Expenditure During Walking with Hand Weights.

    ERIC Educational Resources Information Center

    Makalous, Susan L.; And Others

    1988-01-01

    A study of 11 obese adults who exercised with hand weights concludes that using the weights increases the energy demands of walking but only slightly. Research and results are presented and analyzed. (JL)

  9. Walking with coffee: why does it spill?

    PubMed

    Mayer, H C; Krechetnikov, R

    2012-04-01

    In our busy lives, almost all of us have to walk with a cup of coffee. While often we spill the drink, this familiar phenomenon has never been explored systematically. Here we report on the results of an experimental study of the conditions under which coffee spills for various walking speeds and initial liquid levels in the cup. These observations are analyzed from the dynamical systems and fluid mechanics viewpoints as well as with the help of a model developed here. Particularities of the common cup sizes, the coffee properties, and the biomechanics of walking proved to be responsible for the spilling phenomenon. The studied problem represents an example of the interplay between the complex motion of a cup, due to the biomechanics of a walking individual, and the low-viscosity-liquid dynamics in it. PMID:22680548

  10. Brief questions highlight the need for melanoma information campaigns.

    PubMed

    Foote, Janet A; Poole, Catherine M

    2013-12-01

    Melanoma awareness was briefly assessed at walk/runs held simultaneously in Philadelphia PA, Phoenix AZ, and Seattle WA. Of the participants, 75 % (1521) answered short questions during event registration. Among 1,036 respondents aged 14 years and older, 66 % reported knowing melanoma warning signs. Significantly more respondents with melanoma family history reported having a physician-administered skin exam and knowing warning signs. More than one third of walk/run participants reported no definitive melanoma warning sign knowledge. Self-reported melanoma awareness and detection indices were lowest among Phoenix participants; the event city with the greatest annual sun exposure. Educational efforts for melanoma awareness are critically needed. Selected results of this project were presented in a poster forum at the 2006 Congress for Epidemiology meeting held in Seattle, WA (June 2006). PMID:23996205

  11. Time to prioritise safe walking.

    PubMed

    Toroyan, Tami; Khayesi, Meleckidzedeck; Peden, Margie

    2013-01-01

    This study draws on information from two recently published documents on pedestrian safety and global status of road safety to draw attention to the need to prioritize safe walking in planning and policy at local, national and international levels. The study shows that each year, more than 270 000 pedestrians lose their lives on the world's roads. The study argues that this situation need not persist because proven pedestrian safety interventions exist but do not attract the merit they deserve in many locations. The study further shows that the key risk factors for pedestrian road traffic injury such as vehicle speed, alcohol use by drivers and pedestrians, lack of infrastructure facilities for pedestrians and inadequate visibility of pedestrians are fairly well documented. The study concludes that pedestrian collisions, like all road traffic crashes, should not be accepted as inevitable because they are, in fact, both predictable and preventable. While stressing that reduction or elimination of risks faced by pedestrians is an important and achievable policy goal, the study emphasizes the importance of a comprehensive, holistic approach that includes engineering, enforcement and education measures. PMID:23701478

  12. Design of a walking robot

    NASA Technical Reports Server (NTRS)

    Whittaker, William; Dowling, Kevin

    1994-01-01

    Carnegie Mellon University's Autonomous Planetary Exploration Program (APEX) is currently building the Daedalus robot; a system capable of performing extended autonomous planetary exploration missions. Extended autonomy is an important capability because the continued exploration of the Moon, Mars and other solid bodies within the solar system will probably be carried out by autonomous robotic systems. There are a number of reasons for this - the most important of which are the high cost of placing a man in space, the high risk associated with human exploration and communication delays that make teleoperation infeasible. The Daedalus robot represents an evolutionary approach to robot mechanism design and software system architecture. Daedalus incorporates key features from a number of predecessor systems. Using previously proven technologies, the Apex project endeavors to encompass all of the capabilities necessary for robust planetary exploration. The Ambler, a six-legged walking machine was developed by CMU for demonstration of technologies required for planetary exploration. In its five years of life, the Ambler project brought major breakthroughs in various areas of robotic technology. Significant progress was made in: mechanism and control, by introducing a novel gait pattern (circulating gait) and use of orthogonal legs; perception, by developing sophisticated algorithms for map building; and planning, by developing and implementing the Task Control Architecture to coordinate tasks and control complex system functions. The APEX project is the successor of the Ambler project.

  13. Design of a walking robot

    NASA Astrophysics Data System (ADS)

    Whittaker, William; Dowling, Kevin

    1994-03-01

    Carnegie Mellon University's Autonomous Planetary Exploration Program (APEX) is currently building the Daedalus robot; a system capable of performing extended autonomous planetary exploration missions. Extended autonomy is an important capability because the continued exploration of the Moon, Mars and other solid bodies within the solar system will probably be carried out by autonomous robotic systems. There are a number of reasons for this - the most important of which are the high cost of placing a man in space, the high risk associated with human exploration and communication delays that make teleoperation infeasible. The Daedalus robot represents an evolutionary approach to robot mechanism design and software system architecture. Daedalus incorporates key features from a number of predecessor systems. Using previously proven technologies, the Apex project endeavors to encompass all of the capabilities necessary for robust planetary exploration. The Ambler, a six-legged walking machine was developed by CMU for demonstration of technologies required for planetary exploration. In its five years of life, the Ambler project brought major breakthroughs in various areas of robotic technology. Significant progress was made in: mechanism and control, by introducing a novel gait pattern (circulating gait) and use of orthogonal legs; perception, by developing sophisticated algorithms for map building; and planning, by developing and implementing the Task Control Architecture to coordinate tasks and control complex system functions. The APEX project is the successor of the Ambler project.

  14. Walking as a social practice: dispersed walking and the organisation of everyday practices.

    PubMed

    Harries, Tim; Rettie, Ruth

    2016-07-01

    This paper uses social practice theory to study the interweaving of walking into everyday practices and considers how greater awareness of everyday walking can influence its position within the organisation and scheduling of everyday life. Walking is of policy interest because of its perceived benefits for health. This paper asserts that increased awareness of everyday walking allows users to become more active without having to reschedule existing activities. Using Schatzki's distinction between dispersed and integrative practices, it argues that increasing awareness of dispersed walking can enlist walking into the teleoaffective organisation of some social practices and prompt the performance of new 'health practices' within everyday domains of life such as shopping and employment. While this analysis offers useful insights for the design of behaviour change strategies, it also points to some unintended consequences of using digital feedback to increase walking awareness. In directing the gaze of participants at one particular element of their daily practices, the paper suggests, digital walking feedback provides a 'partial' view of practices: by highlighting the exercise value of walking at the expense of other values it can prompt feedback recipients to pass moral judgements on themselves based on this partial view. A Virtual Abstract of this paper can be found at: https://youtu.be/WV7DUnKD5Mw. PMID:26853086

  15. Quantum Ultra-Walks: Walks on a Line with Spatial Disorder

    NASA Astrophysics Data System (ADS)

    Boettcher, Stefan; Falkner, Stefan

    We discuss the model of a heterogeneous discrete-time walk on a line with spatial disorder in the form of a set of ultrametric barriers. Simulations show that such an quantum ultra-walk spreads with a walk exponent dw that ranges from ballistic (dw = 1) to complete confinement (dw = ∞) for increasing separation 1 <= 1 / ɛ < ∞ in barrier heights. We develop a formalism by which the classical random walk as well as the quantum walk can be treated in parallel using a coined walk with internal degrees of freedom. For the random walk, this amounts to a 2nd -order Markov process with a stochastic coin, better know as an (anti-)persistent walk. The exact analysis, based on the real-space renormalization group (RG), reproduces the results of the well-known model of ``ultradiffusion,'' dw = 1 -log2 ɛ for 0 < ɛ <= 1 / 2 . However, while the evaluation of the RG fixed-points proceeds virtually identical, for the corresponding quantum walk with a unitary coin it fails to reproduce the numerical results. A new way to analyze the RG is indicated. Supported by NSF-DMR 1207431.

  16. Quantum Walks: Theory, Application, and Implementation

    NASA Astrophysics Data System (ADS)

    Schmitz, Albert Thomas

    The quantum walk is a method for conceptualizing and designing quantum computing algorithms and it comes in two forms: the continuous-time and discrete-time quantum walk. The thesis is organized into three parts, each of which looks to develop the concept and uses of the quantum walk. The first part is the theory of the quantum walk. This includes definitions and considerations for the various incarnations of the discrete-time quantum walk and a discussion on the general method for connecting the continuous-time and discrete-time versions. As a result, it is shown that most versions of the discrete-time quantum walk can be put into a general form and this can be used to simulate any continuous-time quantum walk. The second part uses these results for a hypothetical application. The application presented is a search algorithm that appears to scale in the time for completion independent of the size of the search space. This behavior is then elaborated upon and shown to have general qualitative agreement with simulations to within the approximations that are made. The third part introduces a method of implementation. Given a universal quantum computer, the method is discussed and shown to simulate an arbitrary discrete-time quantum walk. Some of the benefits of this method are that half the unitary evolution can be achieved without the use of any gates and there may be some possibility for error detection. The three parts combined suggest a possible experiment, given a quantum computing scheme of sufficient robustness.

  17. Balancing of the anthropomorphous robot walking

    NASA Astrophysics Data System (ADS)

    Devaev, V. M.; Nikitina, D. V.; Fadeev, A. Y.

    2016-06-01

    Anthropomorphic robots are designed a human environment operates: buildings and structures, cabs and etc. The movement of these robots is carried out by walking which provides high throughput to overcome natural and manmade obstacles. The article presents some algorithm results for dynamic walking on the anthropomorphic robot AR601 example. The work is performed according to the Russian Government Program of Competitive Growth of Kazan Federal University.

  18. Mesonic spectroscopy of minimal walking technicolor

    SciTech Connect

    Del Debbio, Luigi; Lucini, Biagio; Patella, Agostino; Pica, Claudio; Rago, Antonio

    2010-07-01

    We investigate the structure and the novel emerging features of the mesonic nonsinglet spectrum of the minimal walking technicolor theory. Precision measurements in the nonsinglet pseudoscalar and vector channels are compared to the expectations for an IR-conformal field theory and a QCD-like theory. Our results favor a scenario in which minimal walking technicolor is (almost) conformal in the infrared, while spontaneous chiral symmetry breaking seems less plausible.

  19. Questioning and Experimentation

    NASA Astrophysics Data System (ADS)

    Mutanen, Arto

    2014-08-01

    The paper is a philosophical analysis of experimentation. The philosophical framework of the analysis is the interrogative model of inquiry developed by Hintikka. The basis of the model is explicit and well-formed logic of questions and answers. The framework allows us to formulate a flexible logic of experimentation. In particular, the formulated model can be interpreted realistically. Moreover, the model demonstrates an explicit logic of knowledge acquisition. So, the natural extension of the model is to apply it to an analysis of the learning process.

  20. Approaches to Cell Biology Teaching: Questions about Questions

    ERIC Educational Resources Information Center

    Allen, Deborah; Tanner, Kimberly

    2002-01-01

    There are many questions to be asked about the pedagogical practice of questioning. Questions provide insight into what students at any age or grade level already know about a topic, which provides a beginning point for teaching. Questions reveal misconceptions and misunderstandings that must be addressed for teachers to move student thinking…

  1. Calcaneal loading during walking and running

    NASA Technical Reports Server (NTRS)

    Giddings, V. L.; Beaupre, G. S.; Whalen, R. T.; Carter, D. R.

    2000-01-01

    PURPOSE: This study of the foot uses experimentally measured kinematic and kinetic data with a numerical model to evaluate in vivo calcaneal stresses during walking and running. METHODS: External ground reaction forces (GRF) and kinematic data were measured during walking and running using cineradiography and force plate measurements. A contact-coupled finite element model of the foot was developed to assess the forces acting on the calcaneus during gait. RESULTS: We found that the calculated force-time profiles of the joint contact, ligament, and Achilles tendon forces varied with the time-history curve of the moment about the ankle joint. The model predicted peak talocalcaneal and calcaneocuboid joint loads of 5.4 and 4.2 body weights (BW) during walking and 11.1 and 7.9 BW during running. The maximum predicted Achilles tendon forces were 3.9 and 7.7 BW for walking and running. CONCLUSIONS: Large magnitude forces and calcaneal stresses are generated late in the stance phase, with maximum loads occurring at approximately 70% of the stance phase during walking and at approximately 60% of the stance phase during running, for the gait velocities analyzed. The trajectories of the principal stresses, during both walking and running, corresponded to each other and qualitatively to the calcaneal trabecular architecture.

  2. Uphill and Downhill Walking in Multiple Sclerosis

    PubMed Central

    Samaei, Afshin; Hajihasani, Abdolhamid; Fatemi, Elham; Motaharinezhad, Fatemeh

    2016-01-01

    Background: Various exercise protocols have been recommended for patients with multiple sclerosis (MS). We investigated the effects of uphill and downhill walking exercise on mobility, functional activities, and muscle strength in MS patients. Methods: Thirty-four MS patients were randomly allocated to either the downhill or uphill treadmill walking group for 12 sessions (3 times/wk) of 30 minutes' walking on a 10% negative slope (n = 17) or a 10% positive slope (n = 17), respectively. Measurements were taken before and after the intervention and after 4-week follow-up and included fatigue by Modified Fatigue Impact Scale; mobility by Modified Rivermead Mobility Index; disability by Guy's Neurological Disability Scale; functional activities by 2-Minute Walk Test, Timed 25-Foot Walk test, and Timed Up and Go test; balance indices by Biodex Balance System; and quadriceps and hamstring isometric muscles by torque of left and right knee joints. Analysis of variance with repeated measures was used to investigate the intervention effects on the measurements. Results: After the intervention, significant improvement was found in the downhill group versus the uphill group in terms of fatigue, mobility, and disability indices; functional activities; balance indices; and quadriceps isometric torque (P < .05). The results were stable at 4-week follow-up. Conclusions: Downhill walking on a treadmill may improve muscle performance, functional activity, and balance control in MS patients. These findings support the idea of using eccentric exercise training in MS rehabilitation protocols. PMID:26917996

  3. Goals and Social Comparisons Promote Walking Behavior.

    PubMed

    Chapman, Gretchen B; Colby, Helen; Convery, Kimberly; Coups, Elliot J

    2016-05-01

    The effectiveness of a pedometer intervention was affected by manipulating the goals given to participants and by providing social comparison feedback about how participants' performance compared with others. In study 1 (n= 148), university staff members received a low, medium, or high walking goal (10%, 50%, or 100% increase over baseline walking). Participants walked 1358 more steps per day (95% confidence interval [CI], 729, 1985), when receiving a high goal than when receiving a medium goal, but a medium goal did not increase walking relative to a low goal (554 more steps; 95% CI, -71,1179). In study 2 (n= 64), participants received individual feedback only or individual plus social comparison feedback. Participants walked 1120 more steps per day (95% CI, 538, 1703) when receiving social comparison feedback than when receiving only individual feedback. Goals and the performance of others act as reference points and influence the effect that pedometer feedback has on walking behavior, illustrating the applicability of the principles of behavioral economics and social psychology to the design of health behavior interventions. PMID:26139447

  4. Developmental Continuity? Crawling, Cruising, and Walking

    PubMed Central

    Adolph, Karen E.; Berger, Sarah E.; Leo, Andrew J.

    2010-01-01

    This research examined developmental continuity between “cruising” (moving sideways holding onto furniture for support) and walking. Because cruising and walking involve locomotion in an upright posture, researchers have assumed that cruising is functionally related to walking. Study 1 showed that most infants crawl and cruise concurrently prior to walking, amassing several weeks of experience with both skills. Study 2 showed that cruising infants perceive affordances for locomotion over an adjustable gap in a handrail used for manual support, but despite weeks of cruising experience, cruisers are largely oblivious to the dangers of gaps in the floor beneath their feet. Study 3 replicated the floor-gap findings for infants taking their first independent walking steps, and showed that new walkers also misperceive affordances for locomoting between gaps in a handrail. The findings suggest that weeks of cruising do not teach infants a basic fact about walking: the necessity of a floor to support their body. Moreover, this research demonstrated that developmental milestones that are temporally contiguous and structurally similar might have important functional discontinuities. PMID:21399716

  5. Does dog-ownership influence seasonal patterns of neighbourhood-based walking among adults? A longitudinal study

    PubMed Central

    2011-01-01

    Background In general dog-owners are more physically active than non-owners, however; it is not known whether dog-ownership can influence seasonal fluctuations in physical activity. This study examines whether dog-ownership influences summer and winter patterns of neighbourhood-based walking among adults living in Calgary, Canada. Methods A cohort of adults, randomly sampled from the Calgary metropolitan area, completed postal surveys in winter and summer 2008. Both winter and summer versions of the survey included questions on dog-ownership, walking for recreation, and walking for transportation in residential neighbourhoods. Participation in neighbourhood-based walking was compared, among dog-owners and non-owners, and in summer and winter, using general linear modeling. Stability of participation in neighbourhood-based walking across summer and winter among dog-owners and non-owners was also assessed, using logistic regression. Results A total of 428 participants participated in the study, of whom 115 indicated owning dogs at the time of both surveys. Dog-owners reported more walking for recreation in their neighbourhoods than did non-owners, both in summer and in winter. Dog-owners were also more likely than non-owners to report participation in walking for recreation in their neighbourhoods, in summer as well as in winter. Dog-owners and non-owners did not differ in the amount of walking that they reported for transportation, either in summer or in winter. Conclusions By acting as cues for physical activity, dogs may help their owners remain active across seasons. Policies and programs related to dog-ownership and dog-walking, such as dog-supportive housing and dog-supportive parks, may assist in enhancing population health by promoting physical activity. PMID:21375754

  6. Quantum walks with tuneable self-avoidance in one dimension

    NASA Astrophysics Data System (ADS)

    Camilleri, Elizabeth; Rohde, Peter P.; Twamley, Jason

    2014-04-01

    Quantum walks exhibit many unique characteristics compared to classical random walks. In the classical setting, self-avoiding random walks have been studied as a variation on the usual classical random walk. Here the walker has memory of its previous locations and preferentially avoids stepping back to locations where it has previously resided. Classical self-avoiding random walks have found numerous algorithmic applications, most notably in the modelling of protein folding. We consider the analogous problem in the quantum setting - a quantum walk in one dimension with tunable levels of self-avoidance. We complement a quantum walk with a memory register that records where the walker has previously resided. The walker is then able to avoid returning back to previously visited sites or apply more general memory conditioned operations to control the walk. We characterise this walk by examining the variance of the walker's distribution against time, the standard metric for quantifying how quantum or classical a walk is. We parameterise the strength of the memory recording and the strength of the memory back-action on the walker, and investigate their effect on the dynamics of the walk. We find that by manipulating these parameters, which dictate the degree of self-avoidance, the walk can be made to reproduce ideal quantum or classical random walk statistics, or a plethora of more elaborate diffusive phenomena. In some parameter regimes we observe a close correspondence between classical self-avoiding random walks and the quantum self-avoiding walk.

  7. Quantum walks with tuneable self-avoidance in one dimension.

    PubMed

    Camilleri, Elizabeth; Rohde, Peter P; Twamley, Jason

    2014-01-01

    Quantum walks exhibit many unique characteristics compared to classical random walks. In the classical setting, self-avoiding random walks have been studied as a variation on the usual classical random walk. Here the walker has memory of its previous locations and preferentially avoids stepping back to locations where it has previously resided. Classical self-avoiding random walks have found numerous algorithmic applications, most notably in the modelling of protein folding. We consider the analogous problem in the quantum setting - a quantum walk in one dimension with tunable levels of self-avoidance. We complement a quantum walk with a memory register that records where the walker has previously resided. The walker is then able to avoid returning back to previously visited sites or apply more general memory conditioned operations to control the walk. We characterise this walk by examining the variance of the walker's distribution against time, the standard metric for quantifying how quantum or classical a walk is. We parameterise the strength of the memory recording and the strength of the memory back-action on the walker, and investigate their effect on the dynamics of the walk. We find that by manipulating these parameters, which dictate the degree of self-avoidance, the walk can be made to reproduce ideal quantum or classical random walk statistics, or a plethora of more elaborate diffusive phenomena. In some parameter regimes we observe a close correspondence between classical self-avoiding random walks and the quantum self-avoiding walk. PMID:24762398

  8. Unproven (questionable) cancer therapies.

    PubMed Central

    Brigden, M L

    1995-01-01

    More than half of all cancer patients use some form of alternative treatment during the course of their illness. Alternative therapies are often started early in patients' illness, and their use is frequently not acknowledged to health care professionals. Some alternative therapies are harmful, and their promoters may be fraudulent. Persons who try alternative cancer therapies may not be poorly educated but may ultimately abandon conventional treatment. Recent attention has focused on aspects of questionable therapies that make these treatments attractive to patients and that may be perceived as being deficient in the practice of conventional health care professionals. Physicians with patients with cancer should always make sure that unproven therapies are discussed early in the therapeutic relationship. They should also attempt to be aware of alternative therapies that are in vogue in their particular geographic area. PMID:8533410

  9. Understanding walking activity in multiple sclerosis: step count, walking intensity and uninterrupted walking activity duration related to degree of disability.

    PubMed

    Neven, An; Vanderstraeten, Annelien; Janssens, Davy; Wets, Geert; Feys, Peter

    2016-09-01

    In multiple sclerosis (MS), physical activity (PA) is most commonly measured as number of steps, while also walking intensity and walking activity duration are keys for a healthy lifestyle. The aim of this study was to investigate (1) the number of steps persons with MS (PwMS) take; (2) the number of steps they take at low and moderate intensity; and (3) their walking activity duration for 2, 3, 6, 10, 12 and 14 uninterrupted minutes; all related to the degree of disability. 64 PwMS participated, distinguished in a mild (n = 31) and moderate MS subgroup (n = 34) based on their ambulatory dysfunction (Disease Steps). Standardized clinical tests were performed, and step data from the StepWatch Activity Monitor were collected for seven consecutive days. The results showed that (1) step count in PwMS was lower than PA recommendations, and is negatively influenced by a higher disability degree. (2) No walking was registered during 77 % of the day. PwMS are making steps for 22 % at low and only 1 % at moderate intensity. (3) Both MS subgroups rarely walk for more than six uninterrupted minutes, especially not at moderate intensity. PwMS need to be encouraged to make steps at moderate intensity, and to make steps for longer periods of time (minimal ten uninterrupted minutes). PMID:27207680

  10. 10 CFR 431.302 - Definitions concerning walk-in coolers and walk-in freezers.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Definitions concerning walk-in coolers and walk-in freezers. 431.302 Section 431.302 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM... enclosed storage space refrigerated to temperatures, respectively, above, and at or below 32...

  11. 10 CFR 431.302 - Definitions concerning walk-in coolers and walk-in freezers.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 3 2011-01-01 2011-01-01 false Definitions concerning walk-in coolers and walk-in freezers. 431.302 Section 431.302 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM... enclosed storage space refrigerated to temperatures, respectively, above, and at or below 32...

  12. Framework for discrete-time quantum walks and a symmetric walk on a binary tree

    SciTech Connect

    Dimcovic, Zlatko; Rockwell, Daniel; Milligan, Ian; Burton, Robert M.; Kovchegov, Yevgeniy; Nguyen, Thinh

    2011-09-15

    We formulate a framework for discrete-time quantum walks, motivated by classical random walks with memory. We present a specific representation of the classical walk with memory 2, on which this is based. The framework has no need for coin spaces, it imposes no constraints on the evolution operator other than unitarity, and is unifying of other approaches. As an example we construct a symmetric discrete-time quantum walk on the semi-infinite binary tree. The generating function of the amplitude at the root is computed in closed form, as a function of time and the initial level n in the tree, and we find the asymptotic and a full numerical solution for the amplitude. It exhibits a sharp interference peak and a power-law tail, as opposed to the exponentially decaying tail of a broadly peaked distribution of the classical symmetric random walk on a binary tree. The probability peak is orders of magnitude larger than it is for the classical walk (already at small n). The quantum walk shows a polynomial algorithmic speedup in n over the classical walk, which we conjecture to be of the order 2/3, based on strong trends in data.

  13. Establishing the range of perceptually natural visual walking speeds for virtual walking-in-place locomotion.

    PubMed

    Nilsson, Niels Christian; Serafin, Stefania; Nordahl, Rolf

    2014-04-01

    Walking-In-Place (WIP) techniques make it possible to facilitate relatively natural locomotion within immersive virtual environments that are larger than the physical interaction space. However, in order to facilitate natural walking experiences one needs to know how to map steps in place to virtual motion. This paper describes two within-subjects studies performed with the intention of establishing the range of perceptually natural walking speeds for WIP locomotion. In both studies, subjects performed a series of virtual walks while exposed to visual gains (optic flow multipliers) ranging from 1.0 to 3.0. Thus, the slowest speed was equal to an estimate of the subjects normal walking speed, while the highest speed was three times greater. The perceived naturalness of the visual speed was assessed using self-reports. The first study compared four different types of movement, namely, no leg movement, walking on a treadmill, and two forms of gestural input for WIP locomotion. The results suggest that WIP locomotion is accompanied by a perceptual distortion of the speed of optic flow. The second study was performed using a 4×2 factorial design and compared four different display field-of-views (FOVs) and two types of movement, walking on a treadmill and WIP locomotion. The results revealed significant main effects of both movement type and field of view, but no significant interaction between the two variables. Particularly, they suggest that the size of the display FOV is inversely proportional to the degree of underestimation of the virtual speeds for both treadmill-mediated virtual walking and WIP locomotion. Combined, the results constitute a first attempt at establishing a set of guidelines specifying what virtual walking speeds WIP gestures should produce in order to facilitate a natural walking experience. PMID:24650984

  14. High Diversity and Low Specificity of Chaetothyrialean Fungi in Carton Galleries in a Neotropical Ant–Plant Association

    PubMed Central

    Nepel, Maximilian; Voglmayr, Hermann; Schönenberger, Jürg; Mayer, Veronika E.

    2014-01-01

    New associations have recently been discovered between arboreal ants that live on myrmecophytic plants, and different groups of fungi. Most of the – usually undescribed – fungi cultured by the ants belong to the order Chaetothyriales (Ascomycetes). Chaetothyriales occur in the nesting spaces provided by the host plant, and form a major part of the cardboard-like material produced by the ants for constructing nests and runway galleries. Until now, the fungi have been considered specific to each ant species. We focus on the three-way association between the plant Tetrathylacium macrophyllum (Salicaceae), the ant Azteca brevis (Formicidae: Dolichoderinae) and various chaetothyrialean fungi. Azteca brevis builds extensive runway galleries along branches of T. macrophyllum. The carton of the gallery walls consists of masticated plant material densely pervaded by chaetothyrialean hyphae. In order to characterise the specificity of the ant–fungus association, fungi from the runway galleries of 19 ant colonies were grown as pure cultures and analyzed using partial SSU, complete ITS, 5.8S and partial LSU rDNA sequences. This gave 128 different fungal genotypes, 78% of which were clustered into three monophyletic groups. The most common fungus (either genotype or approximate species-level OTU) was found in the runway galleries of 63% of the investigated ant colonies. This indicates that there can be a dominant fungus but, in general, a wider guild of chaetothyrialean fungi share the same ant mutualist in Azteca brevis. PMID:25398091

  15. Scaling random walks on arbitrary sets

    NASA Astrophysics Data System (ADS)

    Harris, Simon C.; Williams, David; Sibson, Robin

    1999-01-01

    Let I be a countably infinite set of points in [open face R] which we can write as I={ui: i[set membership][open face Z]}, with uiwalk, when repeatedly rescaled suitably in space and time, looks more and more like a Brownian motion. In this paper we explore the convergence properties of the Markov chain Y on the set I under suitable space-time scalings. Later, we consider some cases when the set I consists of the points of a renewal process and the jump rates assigned to each state in I are perhaps also randomly chosen.This work sprang from a question asked by one of us (Sibson) about ‘driftless nearest-neighbour’ Markov chains on countable subsets I of [open face R]d, work of Sibson [7] and of Christ, Friedberg and Lee [2] having identified examples of such chains in terms of the Dirichlet tessellation associated with I. Amongst methods which can be brought to bear on this d-dimensional problem is the theory of Dirichlet forms. There are potential problems in doing this because we wish I to be random (for example, a realization of a Poisson point process), we do not wish to impose artificial boundedness conditions which would clearly make things work for certain deterministic sets I. In the 1-dimensional case discussed here and in the following paper by Harris, much simpler techniques (where we embed the Markov chain in a Brownian motion using local time) work very effectively; and it is these, rather than the theory of Dirichlet forms, that we use.

  16. Influences on Neighborhood Walking in Older Adults

    PubMed Central

    Gallagher, Nancy Ambrose; Clarke, Philippa J.; Ronis, David L.; Cherry, Carol Loveland; Nyquist, Linda; Gretebeck, Kimberlee A.

    2014-01-01

    The purpose of this cross-sectional survey study was to examine the influence of self-efficacy, outcome expectations and environment on neighborhood walking in older adults with (n=163, mean age=78.7, SD=7.96 years) and without (n=163, mean age=73.6, SD=7.93 years) mobility limitations (controlling for demographic characteristics). Measures included: Neighborhood Physical Activity Questionnaire, Multidimensional Outcome Expectations for Exercise Scale, Neighborhood Environment Walkability Scale, and self-efficacy scales. Multiple regression revealed that in mobility-limited older adults, demographic characteristics, self-efficacy, and outcome expectations explained 17.4% of variance in neighborhood walking, while environment (neighborhood destinations and design) explained 9.5%. Destinations, self-efficacy, gender, and outcome expectations influenced walking. In those without mobility limitations, demographic characteristics, self-efficacy, and outcome expectations explained 15.6% of the variance, while environment explained 5.7%. Self-efficacy, gender, and design influenced walking. Neighborhood walking interventions for older adults should include self-efficacy strategies tailored to mobility status and neighborhood characteristics. PMID:22998660

  17. Cosmic questions: an introduction.

    PubMed

    Primack, J R; Abrams, N E

    2001-12-01

    This introductory talk at the Cosmic Questions conference sponsored by the AAAS summarizes some earlier pictures of the universe and some pictures based on modern physics and cosmology. The uroboros (snake swallowing its tail) is an example of a traditional picture. The Biblical flat-earth picture was very different from the Greek spherical earth-centered picture, which was the standard view until the end of the Middle Ages. Many people incorrectly assume that the Newtonian picture of stars scattered through otherwise empty space is still the prevailing view. Seeing Earth from space shows the power of a new picture. The Hubble Space Telescope can see all the bright galaxies, all the way to the cosmic Dark Ages. We are at the center of cosmic spheres of time: looking outward is looking backward in time. All the matter and energy in the universe can be represented as a cosmic density pyramid. The laws of physics only allow the material objects in the universe to occupy a wedge-shaped region on a diagram of mass versus size. All sizes--from the smallest size scale, the Planck scale, to the entire visible universe--can be represented on the Cosmic Uroboros. There are interesting connections across this diagram, and the human scale lies in the middle. PMID:11797741

  18. Questioning cochlear amplification

    NASA Astrophysics Data System (ADS)

    van der Heijden, Marcel; Versteegh, Corstiaen P. C.

    2015-12-01

    Thirty years ago it was hypothesized that motile processes inject mechanical energy into cochlear traveling waves. This mechanical amplification, alternatively described as negative damping, is invoked to explain both the sensitivity and the nonlinear compression of cochlear responses. There is a recent trend to present cochlear amplification as an established fact, even though the evidence is at most circumstantial and several thorny problems have remained unresolved. We analyze several of these issues, and present new basilar membrane recordings that allowed us to quantify cochlear energy flow. Specifically, we address the following questions: (1) Does auditory sensitivity require narrowband amplification? (2) Has the "RC problem" (lowpass filtering of outer hair cell receptor potential) been resolved? (3) Can OHC motility improve auditory sensitivity? (4) Is there a net power gain between neighboring locations on the basilar membrane? The analyses indicate that mechanical amplification in the cochlea is neither necessary nor useful, and that realizing it by known forms of motility would reduce sensitivity rather than enhance it. Finally, our experimental data show that the peaking of the traveling wave is realized by focusing the acoustic energy rather than amplifying it. (Abbreviations. BM: basilar membrane; CF: characteristic frequency; IHC: inner hair cell; ME: middle ear; MT; mechanotransducer; OHC: outer hair cell; SPL: sound pressure level.)

  19. Question Popularity Analysis and Prediction in Community Question Answering Services

    PubMed Central

    Liu, Ting; Zhang, Wei-Nan; Cao, Liujuan; Zhang, Yu

    2014-01-01

    With the blooming of online social media applications, Community Question Answering (CQA) services have become one of the most important online resources for information and knowledge seekers. A large number of high quality question and answer pairs have been accumulated, which allow users to not only share their knowledge with others, but also interact with each other. Accordingly, volumes of efforts have been taken to explore the questions and answers retrieval in CQA services so as to help users to finding the similar questions or the right answers. However, to our knowledge, less attention has been paid so far to question popularity in CQA. Question popularity can reflect the attention and interest of users. Hence, predicting question popularity can better capture the users’ interest so as to improve the users’ experience. Meanwhile, it can also promote the development of the community. In this paper, we investigate the problem of predicting question popularity in CQA. We first explore the factors that have impact on question popularity by employing statistical analysis. We then propose a supervised machine learning approach to model these factors for question popularity prediction. The experimental results show that our proposed approach can effectively distinguish the popular questions from unpopular ones in the Yahoo! Answers question and answer repository. PMID:24837851

  20. Promoting Student Learning Through Questioning: A Study of Classroom Questions.

    ERIC Educational Resources Information Center

    Edwards, Sandra; Bowman, Mary Ann

    1996-01-01

    A study in a graduate-level occupational therapy class found that questions asked by teachers and the instructional format in which they were asked influenced the frequency and level of student questioning. Subjects were 5 undergraduate and 15 graduate students. It was concluded that improved classroom questioning strategies may contribute to…

  1. Integration of microsphere resonators with bioassay fluidics for whispering gallery mode imaging.

    PubMed

    Kim, Daniel C; Armendariz, Kevin P; Dunn, Robert C

    2013-06-01

    Whispering gallery mode resonators are small, radially symmetric dielectrics that trap light through continuous total internal reflection. The resonant condition at which light is efficiently confined within the structure is linked with refractive index, which has led to the development of sensitive label-free sensing schemes based on whispering gallery mode resonators. One resonator design uses inexpensive high index glass microspheres that offer intrinsically superior optical characteristics, but have proven difficult to multiplex and integrate with the fluidics for sample delivery and fluid exchange necessary for assay development. Recently, we introduced a fluorescence imaging approach that enables large scale multiplexing with microsphere resonators, thus removing one obstacle for assay development. Here we report an approach for microsphere immobilization that overcomes limitations arising from their integration with fluidic delivery. The approach is an adaptation of a calcium-assisted glass bonding method originally developed for microfluidic glass chip fabrication. Microspheres bonded to glass using this technique are shown to be stable with respect to fluid flow and show no detectable loss in optical performance. Measured Q-factors, for example, remain unchanged following sphere bonding to the substrate. The stability of the immobilized resonators is further demonstrated by transferring lipid films onto the immobilized spheres using the Langmuir-Blodgett technique. Bilayers of DOPC doped with GM1 were transferred onto immobilized resonators to detect the binding of cholera toxin to GM1. Binding curves generated from shifts in the whispering gallery mode resonance result in a measured Kd of 1.5 × 10(-11) with a limit of detection of 3.3 pM. These results are discussed in terms of future assay development using microsphere resonators. PMID:23615457

  2. Mean first return time for random walks on weighted networks

    NASA Astrophysics Data System (ADS)

    Jing, Xing-Li; Ling, Xiang; Long, Jiancheng; Shi, Qing; Hu, Mao-Bin

    2015-11-01

    Random walks on complex networks are of great importance to understand various types of phenomena in real world. In this paper, two types of biased random walks on nonassortative weighted networks are studied: edge-weight-based random walks and node-strength-based random walks, both of which are extended from the normal random walk model. Exact expressions for stationary distribution and mean first return time (MFRT) are derived and examined by simulation. The results will be helpful for understanding the influences of weights on the behavior of random walks.

  3. Coin state properties in quantum walks

    PubMed Central

    Andrade, R. F. S.

    2013-01-01

    Recent experimental advances have measured individual coin components in discrete time quantum walks, which have not received the due attention in most theoretical studies on the theme. Here is presented a detailed investigation of the properties of M, the difference between square modulus of coin states of discrete quantum walks on a linear chain. Local expectation values are obtained in terms of real and imaginary parts of the Fourier transformed wave function. A simple expression is found for the average difference between coin states in terms of an angle θ gauging the coin operator and its initial state. These results are corroborated by numerical integration of dynamical equations in real space. The local dependence is characterized both by large and short period modulations. The richness of revealed patterns suggests that the amount of information stored and retrieved from quantum walks is significantly enhanced if M is taken into account. PMID:23756358

  4. Mesoscopic description of random walks on combs.

    PubMed

    Méndez, Vicenç; Iomin, Alexander; Campos, Daniel; Horsthemke, Werner

    2015-12-01

    Combs are a simple caricature of various types of natural branched structures, which belong to the category of loopless graphs and consist of a backbone and branches. We study continuous time random walks on combs and present a generic method to obtain their transport properties. The random walk along the branches may be biased, and we account for the effect of the branches by renormalizing the waiting time probability distribution function for the motion along the backbone. We analyze the overall diffusion properties along the backbone and find normal diffusion, anomalous diffusion, and stochastic localization (diffusion failure), respectively, depending on the characteristics of the continuous time random walk along the branches, and compare our analytical results with stochastic simulations. PMID:26764637

  5. Mesoscopic description of random walks on combs

    NASA Astrophysics Data System (ADS)

    Méndez, Vicenç; Iomin, Alexander; Campos, Daniel; Horsthemke, Werner

    2015-12-01

    Combs are a simple caricature of various types of natural branched structures, which belong to the category of loopless graphs and consist of a backbone and branches. We study continuous time random walks on combs and present a generic method to obtain their transport properties. The random walk along the branches may be biased, and we account for the effect of the branches by renormalizing the waiting time probability distribution function for the motion along the backbone. We analyze the overall diffusion properties along the backbone and find normal diffusion, anomalous diffusion, and stochastic localization (diffusion failure), respectively, depending on the characteristics of the continuous time random walk along the branches, and compare our analytical results with stochastic simulations.

  6. Universal quantum computation by discontinuous quantum walk

    SciTech Connect

    Underwood, Michael S.; Feder, David L.

    2010-10-15

    Quantum walks are the quantum-mechanical analog of random walks, in which a quantum ''walker'' evolves between initial and final states by traversing the edges of a graph, either in discrete steps from node to node or via continuous evolution under the Hamiltonian furnished by the adjacency matrix of the graph. We present a hybrid scheme for universal quantum computation in which a quantum walker takes discrete steps of continuous evolution. This ''discontinuous'' quantum walk employs perfect quantum-state transfer between two nodes of specific subgraphs chosen to implement a universal gate set, thereby ensuring unitary evolution without requiring the introduction of an ancillary coin space. The run time is linear in the number of simulated qubits and gates. The scheme allows multiple runs of the algorithm to be executed almost simultaneously by starting walkers one time step apart.

  7. Humanoid robot Lola: design and walking control.

    PubMed

    Buschmann, Thomas; Lohmeier, Sebastian; Ulbrich, Heinz

    2009-01-01

    In this paper we present the humanoid robot LOLA, its mechatronic hardware design, simulation and real-time walking control. The goal of the LOLA-project is to build a machine capable of stable, autonomous, fast and human-like walking. LOLA is characterized by a redundant kinematic configuration with 7-DoF legs, an extremely lightweight design, joint actuators with brushless motors and an electronics architecture using decentralized joint control. Special emphasis was put on an improved mass distribution of the legs to achieve good dynamic performance. Trajectory generation and control aim at faster, more flexible and robust walking. Center of mass trajectories are calculated in real-time from footstep locations using quadratic programming and spline collocation methods. Stabilizing control uses hybrid position/force control in task space with an inner joint position control loop. Inertial stabilization is achieved by modifying the contact force trajectories. PMID:19665558

  8. Second-harmonic generation of light at 245 nm in a lithium tetraborate whispering gallery resonator.

    PubMed

    Fürst, Josef U; Buse, Karsten; Breunig, Ingo; Becker, Petra; Liebertz, Josef; Bohatý, Ladislav

    2015-05-01

    A millimeter-sized, monolithic whispering gallery resonator made of a lithium tetraborate, Li2B4O7, crystal was employed for doubly resonant second-harmonic generation with a continuous-wave laser source at 490 nm. An intrinsic quality factor of 2×10(8) was observed at the pump wavelength. A conversion efficiency of 2.2% was attained with 5.9 mW of mode-matched pump power. In the lithium tetraborate resonator, it is feasible to achieve phase-matching of second-harmonic generation for pump wavelengths between 486 and 506 nm. PMID:25927751

  9. Spatiotemporal Lugiato-Lefever formalism for Kerr-comb generation in whispering-gallery-mode resonators

    NASA Astrophysics Data System (ADS)

    Chembo, Yanne K.; Menyuk, Curtis R.

    2013-05-01

    We demonstrate that frequency (Kerr) comb generation in whispering-gallery-mode resonators can be modeled by a variant of the Lugiato-Lefever equation that includes higher-order dispersion and nonlinearity. This spatiotemporal model allows us to explore pulse formation in which a large number of modes interact cooperatively. Pulse formation is shown to play a critical role in comb generation, and we find conditions under which single pulses (dissipative solitons) and multiple pulses (rolls) form. We show that a broadband comb is the spectral signature of a dissipative soliton, and we also show that these solitons can be obtained by using a weak anomalous dispersion and subcritical pumping.

  10. Controlled excitation of higher radial order whispering gallery modes with metallic diffraction grating.

    PubMed

    Zhou, Yanyan; Luan, Feng; Gu, Bobo; Yu, Xia

    2015-02-23

    Metallic diffraction grating coupler is investigated for controlled excitation of whispering gallery modes (WGMs) of different radial orders. Based on effective mode index calculations and finite difference time domain method, it is found that higher radial order WGMs can be separated from the fundamental modes by sending them into the opposite propagation direction. By phase-matching designs, the metallic diffraction grating provides extra freedom to switch propagation directions, and is able to selectively enhance or suppress different radial-order WGMs. Such structure offers a simple and practical configuration for various WGM applications including liquid sensing, band pass filtering and fiber lasers. PMID:25836534

  11. Rapid 3D µ-printing of polymer optical whispering-gallery mode resonators.

    PubMed

    Wu, Jushuai; Guo, Xin; Zhang, A Ping; Tam, Hwa-Yaw

    2015-11-16

    A novel microfabrication method for rapid printing of polymer optical whispering-gallery mode (WGM) resonators is presented. A 3D micro-printing technology based on high-speed optical spatial modulator (SLM) and high-power UV light source is developed to fabricate suspended-disk WGM resonator array using SU-8 photoresist. The optical spectral responses of the fabricated polymer WGM resonators were measured with a biconically tapered optical fiber. Experimental results reveal that the demonstrated method is very flexible and time-saving for rapid fabrication of complex polymer WGM resonators. PMID:26698452

  12. Whispering gallery mode photoemission from self-assembled poly-para-phenylenevinylene microspheres

    NASA Astrophysics Data System (ADS)

    Kushida, Soh; Braam, Daniel; Lorke, Axel; Yamamoto, Yohei

    2015-12-01

    Poly[2-methoxy-5-(3,7-dimethyloctyloxy)-1,4-phenylenevinylene] (MDMOPPV) self-assembles to form well-defined spheres with several micrometers in diameter upon addition of a methanol vapor into a chloroform solution of MDMOPPV. The single sphere of MDMOPPV with 5.7 µm diameter exhibits whispering gallery mode (WGM) photoemission upon excitation with focused laser beam. The periodic emission lines are characterized by transverse electric and magnetic WGMs, and Q-factor reaches ˜345 at the highest.

  13. Distribution, diversity, mesonotal morphology, gallery architecture, and queen physogastry of the termite genus Calcaritermes (Isoptera, Kalotermitidae)

    PubMed Central

    Scheffrahn, Rudolf H.

    2011-01-01

    Abstract An updated New World distribution of the genus Calcaritermes is given along with photographs and a key to the New World species outside Mexico. Calcaritermes recessifrons is found to be a junior synonym of Calcaritermes nigriceps. Except for Calcaritermes temnocephalus, pseudergates of the other seven studied Calcaritermes species possess a mesonotal rasp. The rasps suggest a role in propagation of microbes on gallery surfaces and microbial infusion below the wood surface. Calcaritermes temoncephalus is shown to have an unusually large physogastric queens for a kalotermitid and several species produce large eggs. PMID:22287890

  14. Dual-mode temperature compensation technique for laser stabilization to a crystalline whispering gallery mode resonator.

    PubMed

    Fescenko, I; Alnis, J; Schliesser, A; Wang, C Y; Kippenberg, T J; Hänsch, T W

    2012-08-13

    Frequency stabilization of a diode laser locked to a whispering gallery mode (WGM) reference resonator made of a MgF2 single crystal is demonstrated. The strong thermal dependence of the difference frequency between two orthogonally polarized TE an TM modes (dual-mode frequency) of the optically anisotropic crystal material allows sensitive measurement of the resonator's temperature within the optical mode volume. This dual-mode signal was used as feedback for self-referenced temperature stabilization to nanokelvin precision, resulting in frequency stability of 0.3 MHz/h at 972 nm, which was measured by comparing with an independent ultrastable laser. PMID:23038559

  15. Optical apparatus for conversion of whispering-gallery modes into a free space gaussian like beam

    DOEpatents

    Stallard, Barry W.; Makowski, Michael A.; Byers, Jack A.

    1992-01-01

    An optical converter for efficient conversion of millimeter wavelength whispering-gallery gyrotron output into a linearly polarized, free-space Gaussian-like beam. The converter uses a mode-converting taper and three mirror optics. The first mirror has an azimuthal tilt to eliminate the k.sub..phi. component of the propagation vector of the gyrotron output beam. The second mirror has a twist reflector to linearly polarize the beam. The third mirror has a constant phase surface so the converter output is in phase.

  16. Strong coupling between whispering gallery modes and chromium ions in ruby

    NASA Astrophysics Data System (ADS)

    Farr, Warrick G.; Goryachev, Maxim; Creedon, Daniel L.; Tobar, Michael E.

    2014-08-01

    We report the study of interactions between cavity photons and paramagnetic Cr3+ spins in a ruby (Cr3+:Al2O3) whispering gallery mode (WGM) resonator. Examining the system at microwave frequencies and millikelvin temperatures, spin-photon couplings up to 610 MHz or about 5% of photon energy are observed between the impurity spins and high quality factor (Q >105) WGM. Large tunability and spin-spin interaction allows operation in the strong coupling regime. The system exhibits behavior not predicted by the usual Tavis-Cummings model because of interactions within the two-level spin bath, and the existence of numerous photonic modes.

  17. Fabrication of transmon qubits embedded in superconducting whispering gallery mode resonators

    NASA Astrophysics Data System (ADS)

    Serniak, K.; Minev, Z. K.; Pop, I. M.; Frunzio, L.; Schoelkopf, R. J.; Devoret, M. H.

    2015-03-01

    Superconducting whispering gallery mode resonators (WGMRs) can confine up to 98% of two high quality modes in lossless vacuum [APL 103, 142604]. We have fabricated new WGMR-based devices using standard lithography techniques and in which transmon qubits were integrated. The advantages of this transmon-resonator configuration are i) the possibility to perform a targeted study of thin-film quality factor across different methods and steps of fabrication and ii) precise control of the Hamiltonian parameters. Work supported by: IARPA, ARO, and ONR.

  18. Infrared light detection using a whispering-gallery-mode optical microcavity

    SciTech Connect

    Zhu, Jiangang E-mail: ozdemir@seas.wustl.edu Ozdemir, Sahin Kaya E-mail: ozdemir@seas.wustl.edu Yang, Lan E-mail: ozdemir@seas.wustl.edu

    2014-04-28

    We demonstrate a thermal infrared (IR) detector based on an ultra-high-quality-factor (Q) whispering-gallery-mode (WGM) microtoroidal silica resonator and investigate its performance to detect IR radiation at 10 μm wavelength. The bandwidth and the sensitivity of the detector are dependent on the power of a probe laser and the detuning between the probe laser and the resonance frequency of the resonator. The microtoroid IR sensor achieved a noise-equivalent-power (NEP) of 7.46 nW, corresponding to an IR intensity of 0.095 mW/cm{sup 2}.

  19. Detection of nanoparticles with a frequency locked whispering gallery mode microresonator

    NASA Astrophysics Data System (ADS)

    Swaim, Jon D.; Knittel, Joachim; Bowen, Warwick P.

    2013-05-01

    We detect 39 nm × 10 nm gold nanorods using a microtoroid stabilized via the Pound-Drever-Hall method. Real-time detection is achieved with signal-to-noise ratios up to 12.2. These nanoparticles are a factor of three smaller in volume than any other nanoparticle detected using whispering gallery mode sensing to date. We show through repeated experiments that the measurements are reliable and verify the presence of single nanorods on the microtoroid surface using electron microscopy. At our current noise level, the plasmonic enhancement of these nanorods could enable detection of proteins with radii as small as a = 2 nm.

  20. Generalized full-vector multi-mode matching analysis of whispering gallery microcavities

    NASA Astrophysics Data System (ADS)

    Du, Xuan; Vincent, Serge; Faucher, Mathieu; Picard, Marie-Josée; Lu, Tao

    2014-06-01

    We outline a full-vectorial three-dimensional multi-mode matching technique in a cylindrical coordinate system that addresses the mutual coupling among multiple modes copropagating in a perturbed whispering-gallery-mode microcavity. In addition to its superior accuracy in respect to our previously implemented single-mode matching technique, this current technique is suitable for modelling waveguide-to-cavity coupling where the influence of multi-mode coupling is non-negligible. Using this methodology, a robust scheme for hybrid integration of a microcavity onto a silicon-on-insulator platform is proposed.