Neural Coding of Naturalistic Motion Stimuli
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Adaptive Rescaling Maximizes Information Transmission
Neuron, Vol. 26, 695±702, June, 2000, Copyright 2000 by Cell Press Adaptive Rescaling Maximizes Information Transmission Naama Brenner, William Bialek,* Adaptation to mean light level ensures that our visual and Rob de Ruyter van Steveninck responses are matched to the average signal in real NEC Research Institute time, thus maintaining sensitivity to the fluctuations Princeton, New Jersey 08540 around this mean. But the fluctuations themselves are intermittent, such that periods of large fluctuations are interspersed with periods of relative ªquiet.º Recent ob- Summary servations indicate that the intermittency of natural sig- nals is of a special form: statistics such as the variance Adaptation is a widespread phenomenon in nervous and correlation function are stationary over some re- systems, providing flexibility to function under varying gions, with slowly modulated parameters over larger external conditions. Here, we relate an adaptive prop- regions (Ruderman and Bialek, 1994; Nelken et al., 1999). erty of a sensory system directly to its function as a The principle of efficient coding suggests that the ner- carrier of information about input signals. We show vous system should adapt its strategy to these local that the input/output relation of a sensory system in statistical properties of the stimulus. Evidence for such a dynamic environment changes with the statistical statistical adaptation in the early stages of vision has properties of the environment. Specifically, when the been found in the fly (van Hateren, 1997) and in the dynamic range of inputs changes, the input/output vertebrate retina (Smirnakis et al., 1997), where mecha- relation rescales so as to match the dynamic range of nisms of gain control are well known (Shapley and Victor, responses to that of the inputs. -
Music & Film Memorabilia
MUSIC & FILM MEMORABILIA Friday 11th September at 4pm On View Thursday 10th September 10am-7pm and from 9am on the morning of the sale Catalogue web site: WWW.LSK.CO.Uk Results available online approximately one hour following the sale Buyer’s Premium charged on all lots at 20% plus VAT Live bidding available through our website (3% plus VAT surcharge applies) Your contact at the saleroom is: Glenn Pearl [email protected] 01284 748 625 Image this page: 673 Chartered Surveyors Glenn Pearl – Music & Film Memorabilia specialist 01284 748 625 Land & Estate Agents Tel: Email: [email protected] 150 YEARS est. 1869 Auctioneers & Valuers www.lsk.co.uk C The first 91 lots of the auction are from the 506 collection of Jonathan Ruffle, a British Del Amitri, a presentation gold disc for the album writer, director and producer, who has Waking Hours, with photograph of the band and made TV and radio programmes for the plaque below “Presented to Jonathan Ruffle to BBC, ITV, and Channel 4. During his time as recognise sales in the United Kingdom of more a producer of the Radio 1 show from the than 100,000 copies of the A & M album mid-1980s-90s he collected the majority of “Waking Hours” 1990”, framed and glazed, 52 x 42cm. the lots on offer here. These include rare £50-80 vinyl, acetates, and Factory Records promotional items. The majority of the 507 vinyl lots being offered for sale in Mint or Aerosmith, a presentation CD for the album Get Near-Mint condition – with some having a Grip with plaque below “Presented to Jonathan never been played. -
Mono and Multifocals.Wps
Monovision and Multifocal Lenses THE GOAL: To provide you good functional vision without glasses at both distance and near most of the time. There are some demanding visual tasks in which monovision or multifocal (bifocal) lenses may not provide acceptable vision and additional glasses may be needed. MONOVISION Monovision interrupts the natural binocular (both eyes together) vision process by using one eye for distance viewing (usually the dominant eye) and the other eye for intermediate and near viewing. This is not how our visual systems were made, but monovision is an accepted modality and has been used for decades. Adapting to having one eye for distance and one for near takes time to adjust to , and is something that is very easy for some and very difficult for others. As the adaptation process proceeds vision becomes clear at all distances, as the brain suppresses the eye that is not being used. Initially you may feel that your distance vision is blurred by your near eye, as your near eye is focused for near and intermediate distances. This perception of distance blur should be reduced over time as the brain learns to suppress the near eye. Noticing a reduction in stereo vision, or depth perception is normal , as the eyes are not working, or teamed together. Noticing a mild reduction in night vision is normal with monovision. Everybody adapts differently , but is good to continue to try monovision for several consecutive days, or longer, to let the adaptation process begin. Monovision is a learned technique, and everybody’s timetable for adaptation is different. -
Lobula Plate Tangential Cells in Drosophila Melanogaster; Response Properties, Synaptic Organisation & Input Channels”
Lobula Plate Tangential Cells in Drosophila melanogaster ; Response Properties, Synaptic Organization & Input Channels Maximilian Albert Jösch Krotki München 2009 2 Lobula Plate Tangential Cells in Drosophila melanogaster ; Response Properties, Synaptic Organization & Input Channels Dissertation Zur Erlangung des Doktorgrades der Naturwissenschaften (Dr.rer.nat.) der Fakultät für Biologie der Ludwig-Maximilians-Universität München Angefertigt am Max-Planck-Institüt für Neurobiologie, Abteilung „Neuronale Informationsverarbeitung‟ Vorgelegt von Maximilian Albert Jösch Krotki München 2009 3 Hiermit erkläre ich, daß ich die vorliegende Dissertation selbständig und ohne unerlaubte Hilfe angefertigt habe. Sämtliche Experimente wurden von mir selbst durchgeführt, außer wenn explizit auf Dritte verwiesen wird. Ich habe weder anderweitig versucht, eine Dissertation oder Teile einer Dissertation einzureichen bzw. einer Prüfungskommission vorzulegen, noch eine Doktorprüfung durchzuführen. München, den 01.10.2009 1. Gutachter: Prof. Dr. Alexander Borst 2. Gutachter: Prof. Dr. Rainer Uhl Tag der mündlichen Prüfung: 26. November 2009 4 Table of Contents Table of Contents .............................................................................................................................. 5 List of Figures ..................................................................................................................................... 8 1 Abstract ........................................................................................................................................ -
High-Fidelity-1955-Nov.Pdf
November 60 cents SIBELIUS AT 90 by Gerald Abraham A SIBELIUS DISCOGRAPHY by Paul Affelder www.americanradiohistory.com FOR FINE SOUND ALL AROUND Bob Fine, of gt/JZe lwtCL ., has standardized on C. Robert Fine, President, and Al Mian, Chief Mixer, at master con- trol console of Fine Sound, Inc., 711 Fifth Ave., New York City. because "No other sound recording the finest magnetic recording tape media hare been found to meet our exact - you can buy - known the world over for its outstanding performance ing'requirements for consistent, uniform and fidelity of reproduction. Now avail- quality." able on 1/2-mil, 1 -mil and 11/2-mil polyester film base, as well as standard plastic base. In professional circles Bob Fine is a name to reckon auaaaa:.cs 'exceed the most with. His studio, one of the country's largest and exacting requirements for highest quality professional recordings. Available in sizes best equipped, cuts the masters for over half the and types for every disc recording applica- records released each year by independent record lion. manufacturers. Movies distributed throughout the magnetically coated world, filmed TV broadcasts, transcribed radio on standard motion picture film base, broadcasts, and advertising transcriptions are re- provides highest quality synchronized re- corded here at Fine Sound, Inc., on Audio products. cordings for motion picture and TV sound tracks. Every inch of tape used here is Audiotape. Every disc cut is an Audiodisc. And now, Fine Sound is To get the most out of your sound recordings, now standardizing on Audiofilm. That's proof of the and as long as you keep them, be sure to put them consistent, uniform quality of all Audio products: on Audiotape, Audiodiscs or Audiofilm. -
Suzi Fleiszig Researches the Cornea's Resistance To
UNIVERSITY OF CALIFORNIA VOL. 2, NO. 1 | FALL 2009 Berkeley Optometry magazine SUZI FLEISZIG RESEARCHES THE CORNEA’S RESISTANCE TO INFECTION ADVANCING EDUCATION AND RESEARCH AT BERKELEY OPTOMETRY EXECUTIVE EDITOR Lawrence Thal dean’s message MANAGING EDITOR Jennifer C. Martin EDITOR Barbara Gordon EXECUTIVE ART DIRECTOR Molly Sharp E ARE BLESSED TO LIVE IN “INTERESTING TIMES”! PHOTOGRAPHY WAt this writing, the U.S. economy is in the tank, the state of California Ken Huie is in the red, and I’m sure I don’t need to tell you that the budget situation at the University of California continues to be challenging. PRODUCTION MANAGER Molly Sharp In this environment, our priorities are to preserve and maintain our funda- mental missions—teaching, research, and public service. And I’m pleased to say WRITERS/CONTRIBUTORS that Berkeley Optometry continues to excel in all of these through the efforts of Suzi Fleiszig, Lu Chen, Cynthia Dizikes, our dedicated faculty and staff. In this spirit, it seems timely to celebrate some Lawrence Thal, Mika Moy, Pam of the highlights of the last year. Satjawatcharaphong, Joy Sarver Among other things, in this issue of Berkeley Optometry Magazine you will see DESIGN that we have a new faculty and student exchange agreement with Peking Medi- ContentWorks, Inc. cal University (PKU) Third Hospital; one of our students, Brian Snydsman, won the 2008 Essilor Optometry Superbowl at the annual meeting of the American Optometric Association and American Optometric Student Asso- Published by University of California, Berkeley, ciation; Professor Clifton Schor received the Charles F. Prentice Medal from School of Optometry Office of External the American Academy of Optometry at its annual meeting last October; and Relations and Professional Affairs Professor Suzanne Fleiszig (see cover) and David Evans won a grant from the Phone: 510-642-2622, Fax: 510-643-6583 Bill and Melinda Gates Foundation as part of the global Grand Challenges Send comments and letters to: Explorations initiative. -
Corneal Haze and Visual Outcome After Collagen Crosslinking for Keratoconus: a Comparison Between Total Epithelium Off and Partial Epithelial Removal Methods
Original Article Corneal haze and visual outcome after collagen crosslinking for keratoconus: A comparison between total epithelium off and partial epithelial removal methods Hasan Razmjoo, Behrooz Rahimi, Mona Kharraji1, Nima Koosha, Alireza Peyman Department of Ophthalmology, 1Medical Student Research Committee, Isfahan University of Medical Sciences, Isfahan, Iran Abstract Background: Keratoconus is an asymmetric, bilateral, progressive noninflammatory ectasia of the cornea that affects approximately 1 in 2000 of the general population. This may cause a significant negative impact on quality of life. Corneal collagen crosslinking (CXL) is one of the recently introduced methods that have been used to decrease the progression of keratoconus, in particular, as well as other corneal‑thinning processes. Materials and Methods: A total of 44 keratoconic eyes of 22 patients were enrolled in this randomized prospective study, after obtaining informed consent. In the first group, the corneal epithelium were totally removed and in the second group, the central 3 mm of epithelium was kept intact and partial removal was performed. After collagen crosslinking in both groups, comprehensive ophthalmologic examination was performed on all patients before and 6 months after the surgery. This article is registered at www.clinicaltrial.gov with registration number NCT01809977. Results: The difference between the two groups was not statistically significant regarding postoperative corneal haziness, refraction, and visual acuity (P > 0.05). However, comparison of pre‑ and postoperative parameters within each group revealed that total removal of the cornea has resulted in significant improvement of K‑max (P value: 0.01) and Q‑value (P value: 0.009); while eyes in partial removal group had better improvement of corrected vision (P value: 0.006). -
Light Propagation Through the Eye: Numerical Considerations and Applications to Presbylasik Surgery Analysis
Light propagation through the eye: numerical considerations and applications to presbylasik surgery analysis Julián Espinosa Tomás Optics Department, University of Alicante Group of Optics and Vision Science Carlos Illueca, PhD. David Mas, PhD. Jorge Pérez, PhD. Julián Espinosa, MSc. Vissum Corporation, Alicante Jorge Alió, PhD. Dolores Ortiz, PhD. Esperanza Sala, OD. Light patterns calculation inside the eye Transmittance evaluation of cornea Transmittance evaluation of crystalline lens Wave propagation (angular spectrum) up to the plane of interest. Applications to presbylasik surgery analysis Corneal transmittance evaluation: - Geometrical configuration 2 surfaces 1st surface: Corneal topography 2nd surface: Dubbelman 2003 =6.6 − 0.005 × 2 2 2 R2 age xy+ +(1 + Qz2 ) − 2 Rz 2 = 0 Q2 = −0.1 − 0.007 × age Corneal transmittance evaluation: - Optical path length Crystalline lens transmittance evaluation Dubbelman 2001 (Scheimpflug photography ) x2+ y 2 +(1 + Qz ) 2 − 2 Rz = 0 = − × =−6.4 + 0.03 × Rant 12.9 0.057 age ; Qant age =− + × =−6.0 + 0.07 × Rpost 6.2 0.012 age ; Qpost age Crystalline lens transmittance evaluation opznzzii≈+1( 21 ii −)cosδ 102 i +∆−( z i) cos ( δ 12 ii + δ ) Wave propagation Convergent patterns calculation λz exp −iπ m ɶ 2 × ()∆x 2 0 ()u∝ DFT −1 z µ 2 m∆ x m2 ()∆ x ×DFT u0 − i π 0 1 0 exp 2 N λ N z c ∆x2 z≤0 ≤ z Nyquist condition λN c zc = 20mm λ = 633nm Total eye ∆x= 6.7mm N = 3600 0 Φ =3 ∆x p()4 0 Wave propagation 2 ∆x0 Nyquist condition: Nλ ≥ zc N κ >1 N′ = λ′ = κλ Let us define , κ and 1 1 ∆ξ ∆ξ = ∆ξ ′ = = ′ δ x0 δx0 κ ′ ′ ∆x0 ∆ξ = N ∆x0 = ∆ x z ∆ξ′ ∆x= N ′ z Wave propagation Rectangle function κ=1 vs. -
A Novel Vertebrate Eye Using Both Refractive and Reflective
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Elsevier - Publisher Connector Current Biology 19, 108–114, January 27, 2009 ª2009 Elsevier Ltd All rights reserved DOI 10.1016/j.cub.2008.11.061 Report A Novel Vertebrate Eye Using Both Refractive and Reflective Optics Hans-Joachim Wagner,1 Ron H. Douglas,2,* mirror, and computer modeling indicates that this provides Tamara M. Frank,3 Nicholas W. Roberts,4,6 a well-focused image. This is the first report of an ocular and Julian C. Partridge5 image being formed in a vertebrate eye by a mirror. 1Anatomisches Institut Universita¨ tTu¨ bingen Results and Discussion O¨ sterbergstrasse 3 72074 Tu¨bingen The eyes of Dolichopteryx longipes have been described once Germany before [6]. However, relying on a single formalin-fixed spec- 2Henry Welcome Laboratory for Vision Sciences imen, this study was understandably incomplete and, in Department of Optometry and Visual Science places, erroneous. On a recent expedition, we caught a live City University specimen of this species, allowing a more thorough descrip- Northampton Square tion of its eyes. London EC1V 0HB UK General Ocular Morphology and Eyeshine 3Center for Ocean Exploration and Deep-Sea Research In dorsal view, D. longipes has two upward-pointing eyes, Harbor Branch Oceanographic Institute each with a dark swelling on its lateral face (Figures 1A and Florida Atlantic University 1B). Histological sectioning shows that each eye consists of 5600 U.S. 1 N two parts, largely separated by a dividing septum: the main, Fort Pierce, FL 34946 cylindrical, ‘‘tubular’’ eye (approximately 6 mm high and USA 4 mm wide) and a smaller, ovoid outgrowth from the lateral 4The Photon Science Institute wall of the cylinder (the diverticulum, approximately 2.6 mm School of Physics and Astronomy maximum height and 2.2 mm maximum width) (Figure 2). -
Optical Modeling of Schematic Eyes and the Ophthalmic Applications
University of Tennessee, Knoxville TRACE: Tennessee Research and Creative Exchange Doctoral Dissertations Graduate School 8-2009 Optical Modeling of Schematic Eyes and the Ophthalmic Applications Bo Tan University of Tennessee - Knoxville Follow this and additional works at: https://trace.tennessee.edu/utk_graddiss Part of the Atomic, Molecular and Optical Physics Commons Recommended Citation Tan, Bo, "Optical Modeling of Schematic Eyes and the Ophthalmic Applications. " PhD diss., University of Tennessee, 2009. https://trace.tennessee.edu/utk_graddiss/63 This Dissertation is brought to you for free and open access by the Graduate School at TRACE: Tennessee Research and Creative Exchange. It has been accepted for inclusion in Doctoral Dissertations by an authorized administrator of TRACE: Tennessee Research and Creative Exchange. For more information, please contact [email protected]. To the Graduate Council: I am submitting herewith a dissertation written by Bo Tan entitled "Optical Modeling of Schematic Eyes and the Ophthalmic Applications." I have examined the final electronic copy of this dissertation for form and content and recommend that it be accepted in partial fulfillment of the requirements for the degree of Doctor of Philosophy, with a major in Physics. James W. L. Lewis, Major Professor We have read this dissertation and recommend its acceptance: Ying-Ling Chen, Horace W. Crater, Christian Parigger, Ming Wang Accepted for the Council: Carolyn R. Hodges Vice Provost and Dean of the Graduate School (Original signatures are on file with official studentecor r ds.) To the Graduate Council: I am submitting herewith a dissertation written by Bo Tan entitled ―Optical modeling of schematic eyes and the ophthalmic applications.‖ I have examined the final electronic copy of this dissertation for form and content and recommend that it be accepted in partial fulfillment of requirements for the degree of Doctor of Philosophy, with a major in Physics. -
Table of Contents
1 •••I I Table of Contents Freebies! 3 Rock 55 New Spring Titles 3 R&B it Rap * Dance 59 Women's Spirituality * New Age 12 Gospel 60 Recovery 24 Blues 61 Women's Music *• Feminist Music 25 Jazz 62 Comedy 37 Classical 63 Ladyslipper Top 40 37 Spoken 65 African 38 Babyslipper Catalog 66 Arabic * Middle Eastern 39 "Mehn's Music' 70 Asian 39 Videos 72 Celtic * British Isles 40 Kids'Videos 76 European 43 Songbooks, Posters 77 Latin American _ 43 Jewelry, Books 78 Native American 44 Cards, T-Shirts 80 Jewish 46 Ordering Information 84 Reggae 47 Donor Discount Club 84 Country 48 Order Blank 85 Folk * Traditional 49 Artist Index 86 Art exhibit at Horace Williams House spurs bride to change reception plans By Jennifer Brett FROM OUR "CONTROVERSIAL- SUffWriter COVER ARTIST, When Julie Wyne became engaged, she and her fiance planned to hold (heir SUDIE RAKUSIN wedding reception at the historic Horace Williams House on Rosemary Street. The Sabbats Series Notecards sOk But a controversial art exhibit dis A spectacular set of 8 color notecards^^ played in the house prompted Wyne to reproductions of original oil paintings by Sudie change her plans and move the Feb. IS Rakusin. Each personifies one Sabbat and holds the reception to the Siena Hotel. symbols, phase of the moon, the feeling of the season, The exhibit, by Hillsborough artist what is growing and being harvested...against a Sudie Rakusin, includes paintings of background color of the corresponding chakra. The 8 scantily clad and bare-breasted women. Sabbats are Winter Solstice, Candelmas, Spring "I have no problem with the gallery Equinox, Beltane/May Eve, Summer Solstice, showing the paintings," Wyne told The Lammas, Autumn Equinox, and Hallomas. -
Real-Time Encoding of Motion: Answerable Questions and Questionable Answers from the Fly’S Visual System
From: Motion Vision - Computational, Neural, and Ecological Constraints Edited by Johannes M. Zanker and Jochen Zeil Springer Verlag, Berlin Heidelberg New York, 2001 Real-Time Encoding of Motion: Answerable Questions and Questionable Answers from the Fly’s Visual System Rob de Ruyter van Steveninck1, Alexander Borst2 and William Bialek1 1NEC Research Institute, Princeton, USA; 2ESPM-Division of Insect Biology, University of California at Berkeley, Berkeley, USA 1. Introduction Much of what we know about the neural processing of sensory information has been learned by studying the responses of single neurones to rather simplified stimuli. The ethologists, however, have argued that we can reveal the full richness of the nervous system only when we study the way in which the brain deals with the more complex stimuli that occur in nature. On the other hand it is possible that the processing of natural signals is decomposable into steps that can be understood from the analysis of simpler signals. But even then, to prove that this is the case one must do the experiment and use complex natural stimuli. In the past decade there has been renewed interest in moving beyond the simple sensory inputs that have been the workhorse of neurophysiology, and a key step in this program has been the development of more powerful tools for the analysis of neural responses to complex dynamic inputs. The motion sensitive neurones of the fly visual sys- tem have been an important testing ground for these ideas, and there have been several key results from this work: 1. The sequence of spikes from a motion sensitive neurone can be decoded to recover a continuous estimate of the dynamic velocity trajectory (Bialek et al.