Science.gov

Sample records for huxley correspondence letters

  1. A correspondence between the models of Hodgkin-Huxley and FitzHugh-Nagumo revisited

    NASA Astrophysics Data System (ADS)

    Postnikov, Eugene B.; Titkova, Olga V.

    2016-11-01

    We present the discussion on the possibility to scale the classical dimensionless FitzHugh-Nagumo model of neuronal self-sustained oscillations to the range of variables corresponding to the results, which are provided by the biophysically relevant reduced two-dimensional Hodgkin-Huxley equations (the Rinzel model). It is shown that there exists a relatively simple choice of affine transformation, which results in time-dependent solutions, which reproduce with a high accuracy the time course of the recovery variable and the sharp onsets (intervals of fast motions on a phase trajectories) of the voltage spikes. As for the latter, the reasons for unavoidable difference are discussed as well as a necessity of taking into account applied current values during such a scaling procedure.

  2. 19 CFR 145.3 - Opening of letter class mail; reading of correspondence prohibited.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 2 2010-04-01 2010-04-01 false Opening of letter class mail; reading of... HOMELAND SECURITY; DEPARTMENT OF THE TREASURY (CONTINUED) MAIL IMPORTATIONS General Provisions § 145.3 Opening of letter class mail; reading of correspondence prohibited. (a) Matter in addition...

  3. 19 CFR 145.3 - Opening of letter class mail; reading of correspondence prohibited.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 19 Customs Duties 2 2012-04-01 2012-04-01 false Opening of letter class mail; reading of... HOMELAND SECURITY; DEPARTMENT OF THE TREASURY (CONTINUED) MAIL IMPORTATIONS General Provisions § 145.3 Opening of letter class mail; reading of correspondence prohibited. (a) Matter in addition...

  4. 19 CFR 145.3 - Opening of letter class mail; reading of correspondence prohibited.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 2 2011-04-01 2011-04-01 false Opening of letter class mail; reading of... HOMELAND SECURITY; DEPARTMENT OF THE TREASURY (CONTINUED) MAIL IMPORTATIONS General Provisions § 145.3 Opening of letter class mail; reading of correspondence prohibited. (a) Matter in addition...

  5. 19 CFR 145.3 - Opening of letter class mail; reading of correspondence prohibited.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 19 Customs Duties 2 2013-04-01 2013-04-01 false Opening of letter class mail; reading of... HOMELAND SECURITY; DEPARTMENT OF THE TREASURY (CONTINUED) MAIL IMPORTATIONS General Provisions § 145.3 Opening of letter class mail; reading of correspondence prohibited. (a) Matter in addition...

  6. 19 CFR 145.3 - Opening of letter class mail; reading of correspondence prohibited.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 19 Customs Duties 2 2014-04-01 2014-04-01 false Opening of letter class mail; reading of... HOMELAND SECURITY; DEPARTMENT OF THE TREASURY (CONTINUED) MAIL IMPORTATIONS General Provisions § 145.3 Opening of letter class mail; reading of correspondence prohibited. (a) Matter in addition...

  7. The Genesis of Reading Ability: What Helps Children Learn Letter-Sound Correspondences?

    ERIC Educational Resources Information Center

    Castles, Anne; Coltheart, Max; Wilson, Katherine; Valpied, Jodie; Wedgwood, Joanne

    2009-01-01

    Knowledge of letter-sound correspondences underpins successful reading acquisition, and yet little is known about how young children acquire this knowledge and what prior information they bring to the learning process. In this study, we used an experimental training design to examine whether either prior letter awareness or prior phonemic…

  8. Instruction in Letter-Sound Correspondences for Children with Autism and Limited Speech

    ERIC Educational Resources Information Center

    Benedek-Wood, Elizabeth; McNaughton, David; Light, Janice

    2016-01-01

    This study used a multiple probe across participants' research design to evaluate the effects of instruction on the acquisition of letter-sound correspondences (LSCs) by three young children with autism spectrum disorder and limited speech. All three children (ages 3-5 years) reached criterion for identifying the LSCs targeted during instruction,…

  9. Comparison of fixed and gradual array when teaching sound-letter correspondence to two children with autism who use AAC.

    PubMed

    Johnston, Susan S; Buchanan, Sara; Davenport, Lisa

    2009-06-01

    The purpose of this study was to compare two conditions for teaching two children with autism (ages 4;10 and 5;4) who used Augmentative and Alternative Communication (AAC) to point to the printed letter that corresponded to the spoken letter sounds of /t/ and /m/. In one condition (gradual array), the printed letter was first presented in isolation and then distracter letters were gradually introduced. In the other condition (fixed array), the printed letter was immediately presented in combination with seven distracter letters. Using an alternating treatment design, results revealed that the fixed array condition resulted in a faster rate of acquisition of target skills for both participants. Implications and directions for future research are discussed.

  10. Thomas Birch's 'Weekly Letter' (1741-66): correspondence and history in the mid-eighteenth-century Royal Society.

    PubMed

    Ellis, Markman

    2014-09-20

    Thomas Birch (1705-66), Secretary of the Royal Society from 1752 to 1765, and Philip Yorke, second Earl of Hardwicke (1720-90), wrote a 'Weekly Letter' from 1741 to 1766, an unpublished correspondence of 680 letters now housed in the British Library (Additional Mss 35396-400). The article examines the dimensions and purposes of this correspondence, an important conduit of information for the influential coterie of the 'Hardwicke circle' gathered around Yorke in the Royal Society. It explores the writers' self-conception of the correspondence, which was expressed in deliberately archaic categories of seventeenth-century news exchange, such as the newsletter, aviso and a-la-main. It shows how the letter writers negotiated their difference in status through the discourse of friendship, and concludes that the 'Weekly Letter' constituted for the correspondents a form of private knowledge, restricted in circulation to their discrete group, and as such unlike the open and networked model of Enlightenment science.

  11. Letters from Dom Pedro II to professor Brown-Séquard: imperial correspondence and neurophysiology.

    PubMed

    Teive, Hélio A G; Germiniani, Francisco M B; Munhoz, Renato P; Lees, Andrew J

    2012-08-01

    The authors have analyzed the content of a selection of letters written by Dom Pedro II, the Emperor of Brazil, and sent to Doctor Charles Brown-Séquard, the famous neurologist, between 1876 and 1885. The content of those letters focuses mainly on his wife's, Princess Thereza Cristina, health issues and Dom Pedro's personal desire to foster the research into the physiological study of the nervous system.

  12. Friendly Letters on the Correspondence of Helen Keller, Anne Sullivan, and Alexander Graham Bell.

    ERIC Educational Resources Information Center

    Blatt, Burton

    1985-01-01

    Excerpts from the letters between Alexander Graham Bell and Anne Sullivan and Helen Keller are given to illustrate the educational and personal growth of Helen Keller as well as the educational philosophy of Bell regarding the education of the deaf blind. (DB)

  13. Letters

    NASA Astrophysics Data System (ADS)

    2001-03-01

    The Editor welcomes letters, by e-mail to ped@iop.org or by post to Dirac House, Temple Back, Bristol BS1 6BE Contents: Force on a pendulum Sound slows down Bond is back Force on a pendulum The simple pendulum has been used by several educationalists for investigating the patterns of thinking among students and their observations that Aristotelian thinking persists among students at college level. I had also considered the simple pendulum in my 1985 letter in Physics Today [1], so I was interested to read the test given by Lenka Czudková and Jana Musilová [2]. When students were asked to draw net forces acting on the particle at various positions, 31.9% of students believed that the net force was tangential to the particle's path the whole time. To me this is no surprise because in our derivation of the equation for the period of a simple pendulum we assume that the unbalanced sine component provides the restoring force for the harmonic motion of the bob. Of course, Czudková and Musilová's question asked students for the net force on the particle, not the component. The student's answer fits well with the logic of the equilibrium of forces and the parallelogram law. Lastly, let me bring out the similarity between the student's answer and the thinking of George Gamow. He used to call positrons 'donkey' electrons because of their displacement against the applied force, before Paul Dirac termed them positrons. Victor Weisskeptf told me this anecdote in a letter in May 1982. References [1] Sathe D 1985 Phys. Today 38 144 [2] Czudková L and Musilová J 2000 Phys. Educ. 35 428 Dileep V Sathe Dadawala Jr College, Pune, India Sound slows down Without wanting to stir up more trouble amongst the already muddy waters of Physics teaching, consider how many times you have heard (or, more worryingly, read) this: 'Sound waves travel faster in a denser material' But...The velocity of simple longitudinal waves in a bulk medium is given by v = (K/ρ)1/2 where K is

  14. Letter to the Editor of Communications in Statistics and Copies of Documenting Correspondence.

    DTIC Science & Technology

    1980-06-01

    snowboard data from the total network yet in any of our own papers. We have restricted our publications to date to data from the permanently manned...better than others). We are comparing snowboard data (7 years) with corresponding shielded precipitation gages at the respective sites (2 years only

  15. The correspondence of Thomas Dale (1700-1750): Botany in the transatlantic Republic of Letters.

    PubMed

    Cook, William J

    2012-03-01

    This paper seeks to provide a full account of the life and career of Dr. Thomas Dale (1700-1750), with particular reference to his botanical works and correspondence. Born in Hoxton, London, Dale studied medicine at Leiden and engaged fully in the social, literary and epistolary network in which botany was practised in eighteenth-century England. In 1730, however, Dale relocated to the British colonial port of Charles Town, South Carolina. Here he continued to engage in a transatlantic network of botanical exchange and discussion, corresponding on equal and reciprocal terms with his former colleagues in England. Where Dale differs from naturalists in South Carolina before him is that his motives for pursuing botany and for corresponding with English naturalists were located firmly in the New World. Such a conclusion forms a valuable, albeit small contribution to models for the development of national scientific cultures in the imperial world. Similarly, Dale's pursuit of botanical information in South Carolina provides a small amount of material with which to illustrate currently fashionable models for the mediated exchange and circulation of scientific knowledge.

  16. Letters

    NASA Astrophysics Data System (ADS)

    2001-01-01

    The Editor welcomes letters, by e-mail to ped@iop.org or by post to Dirac House, Temple Back, Bristol BS1 6BE, UK. Contents: Maths for physics? Help! Fire! Energy and mass Maths for physics? As a maths graduate working as a university research associate I should be well qualified to support my daughter, who has just started AS-level physics, with the maths she needs for the course. There seems to be little integration between the maths and physics departments, so that maths needed for physics has not yet been covered in maths lessons. This is a problem I remember from my own school days, but the shorter timescale and modular nature of the AS and A2 levels means that it is essential that this mismatch of knowledge is resolved now. I would like to know whether physics teachers in the UK have encountered this problem and whether there is a deficiency in the maths syllabus in relation to the requirements of the AS and A2 levels in Physics or whether this is a problem peculiar to my daughter's school. Eleanor Parent of A-level student, Sheffield, UK Help! Fire! Is there a crisis in physics education? Is physics didactics coming to an end? Yes and no. Being a delegate from Norway at the on-going conference Physics on Stage (6-10 November 2000) at CERN in Geneva, I have had the opportunity to discuss this with people from all over Europe. Yes, there is a crisis. (Look at the proceedings for details on this.) I'd like to take a broader look at this situation. Like Hari Seldon in Isaac Asimov's Foundation Trilogy, I believe that there is nothing like a real crisis to get things going... Famous is the quote from the American Patent Office around 1890: 'Everything has been invented that could be invented'. Fortunately, this spurred action. The Michelson and Morley experiment heralded a most exciting period for physics. Just a cosmic blink later we put a person on the Moon. Coming back to the crisis - I am certain that in the near future we will see an interesting development

  17. Letters

    NASA Astrophysics Data System (ADS)

    2001-07-01

    The Editor welcomes letters, by e-mail to ped@iop.org or by post to Dirac House, Temple Back, Bristol BS1 6BE, UK. Contents: Alternative view of education in Zambia Pedantry or compromise Alternative view of education in Zambia I have just read the 'On the Map' report of the International School of Lusaka with very mixed feelings (Physics Education, March 2001). I have recently spent some time in Zambia, in Lusaka, and share Sue Pears' love for the country and the Zambians. The ISL is indeed a good, prestigious school, similar to International Schools in many other countries. But, as in most other developing countries, there is enormous variation between the different types of schooling, and the ISL is at one end of the spectrum. Most schools in Zambia are less favoured. Zambia is a wonderful, beautiful country full of the most friendly and resourceful people I know. It is also a very poor country. It is a country of enormous contrasts and its schools reflect that variation. It has a tiny, affluent 'middle' class of professionals, politicians, businessmen, employees of international businesses and NGOs—nearly all paid from overseas budgets. It has an enormous majority of poor folk, cheerfully living in very basic conditions but sharing their lives in extended families without complaint. The government is virtually bankrupt, and consequently those paid by the government—teachers, police, nurses etc—get a pittance. The wage for a teacher in a typical school is #20 per month (compared to a typical teacher in the UK who gets 100 times more, about #2000 per month). The GNP in Zambia is about 1 per day per person, and this has to pay for all the schools, hospitals, police, and the civic infrastructure that we take so much for granted (the GNP in UK is about 60 per day per person). Consequently most state schools do not have resources; they have a classroom and a teacher but little else. What resources the school has will be paid for by the school fees that every

  18. Letters

    NASA Astrophysics Data System (ADS)

    2001-09-01

    The Editor welcomes letters, by e-mail to ped@iop.org or by post to Dirac House, Temple Back, Bristol BS1 6BE, UK. Contents: M-set as metaphor The abuse of algebra M-set as metaphor 'To see a World in a Grain of Sand And a Heaven in a Wild Flower Hold Infinity in the palm of your hand And Eternity in an hour' William Blake's implied relativity of spatial and temporal scales is intriguing and, given the durability of this worlds-within-worlds concept (he wrote in 1803) in art, literature and science, the blurring of distinctions between the very large and the very small must strike some kind of harmonious chord in the human mind. Could this concept apply to the physical world? To be honest, we cannot be absolutely sure. Most cosmological thinking still retains the usual notions of a finite universe and an absolute size scale extending from smallest to largest objects. In the boundless realm of mathematics, however, the story is quite different. The M-set was discovered by the French mathematician Benoit Mandelbrot in 1980, created by just a few simple lines of computer code that are repeated recursively. As in Blake's poem, this 'world' has no bottom we have an almost palpable archetype for the concept of infinity. I would use the word 'tangible', but one of the defining features of the M-set is that nowhere in the labyrinth can one find a surface smooth enough for a tangent. Upon magnification even surfaces that appeared to be smooth explode with quills and scrolls and lightning bolts and spiral staircases. And there is something more, something truly sublime. Observe a small patch with unlimited magnifying power and, as you observe the M-set on ever-smaller scales, down through literally endless layers of ornate structure, you occasionally come upon a rapidly expanding cortex of dazzling colour with a small black structure at its centre. The black spot appears to be the M-set itself! There is no end to the hierarchy, no bottom-most level, just endless recursive

  19. Letters

    NASA Astrophysics Data System (ADS)

    2001-05-01

    The Editor welcomes letters, by e-mail to ped@iop.org or by post to Dirac House, Temple Back, Bristol BS1 6BE, UK. Contents: Quantum uncertainties Reflections in a plastic box A brief history of quantum physics Correction Grammar and gender Quantum uncertainties Whilst I enjoyed Gesche Pospiech's article ('Uncertainty and complementarity: the heart of quantum physics' 2000 Phys. Educ. 35 393 9) I would like to expand on two comments he makes. Firstly the author claims that QM is linear, and a consequence of this is that any two superimposed states form an admissible third state. This is rather too sweeping, as it is true only for degenerate states. Otherwise quantum mechanics would allow a continuum of energies between states by a simple admixture of levels. The proof of this statement is trivial. For a Hamiltonian H and two orthogonal wavefunctions, ψ1 and ψ2 with energies E1 and E2 then (ψ1 + ψ2) is not an eigenfunction of that Hamiltonian as H(ψ1 + ψ2) = E1ψ1 + E2ψ2 ≠ E(ψ1 + ψ2) for any value of E, unless E1 = E2. Secondly Pospiech states that quantum objects show wave- or particle-like behaviour, depending on the measuring apparatus, and that occasionally experiments (such as Taylor's) reveal both. I would contest the validity of this type of thinking. All experiments on quantum objects reveal both types of behaviour—even ones which simply show straight line motion of photons. What is important, in addition, is our interpretation of the results. It takes an understanding of QED, for example, to see that an experiment which otherwise shows particle behaviour is, in fact, showing quantum behaviour. More contentiously though I would suggest that detection apparatus is incapable of detecting anything other than particles. Wave-like behaviour is revealed only by an analysis of the paths the particle could have taken. In other words, the interference of continuous fields sometimes predicts the same results when the detection is averaged over many events

  20. The Effectiveness of a Multi Sensory Approach in Improving Letter-Sound Correspondence among Mild Intellectual Disabled Students in State of Kuwait

    ERIC Educational Resources Information Center

    Moustafa, Amr; Ghani, Mohd Zuri

    2016-01-01

    This research examines the effectiveness of multi sensory approach for the purpose of improving the knowledge on English Letter sound correspondence among mild disabled students in the state of Kuwait. The discussion in this study is based on the multisensory approach that could be applied in the teaching of reading skills as well as phonemic…

  1. Supplemental Flashcard Drill Methods for Efficiently Helping At-Risk Kindergartners Make Letter-Sound Correspondences: Does Presentation Arrangement of Words Matter?

    ERIC Educational Resources Information Center

    Griffin, Crystal; Joseph, Laurice M.

    2015-01-01

    Variations of supplemental flashcard drill and practice instructional procedures (i.e., massed practice and interspersal presentation arrangements of words) were examined for six kindergartners who struggled making letter-sound correspondences. Findings revealed that the children demonstrated the highest learning rates when the presentation…

  2. Evolution and Education: Lessons from Thomas Huxley

    ERIC Educational Resources Information Center

    Lyons, Sherrie Lynne

    2010-01-01

    Thomas Huxley more than anyone else was responsible for disseminating Darwin's theory in the western world and maintained that investigating the history of life should be regarded as a purely scientific question free of theological speculation. The content and rhetorical strategy of Huxley's defense of evolution is analyzed. Huxley argued that the…

  3. Circles of Confidence in Correspondence: Modeling Confidentiality and Secrecy in Knowledge Exchange Networks of Letters and Drawings in the Early Modern Period.

    PubMed

    van den Heuvel, Charles; Weingart, Scott B; Spelt, Nils; Nellen, Henk

    2016-01-01

    Science in the early modern world depended on openness in scholarly communication. On the other hand, a web of commercial, political, and religious conflicts required broad measures of secrecy and confidentiality; similar measures were integral to scholarly rivalries and plagiarism. This paper analyzes confidentiality and secrecy in intellectual and technological knowledge exchange via letters and drawings. We argue that existing approaches to understanding knowledge exchange in early modern Europe--which focus on the Republic of Letters as a unified entity of corresponding scholars--can be improved upon by analyzing multilayered networks of communication. We describe a data model to analyze circles of confidence and cultures of secrecy in intellectual and technological knowledge exchanges. Finally, we discuss the outcomes of a first experiment focusing on the question of how personal and professional/official relationships interact with confidentiality and secrecy, based on a case study of the correspondence of Hugo Grotius.

  4. Correspondence standards

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This revised handbook covers the drafting, preparation, and review of NASA letters, memorandums, informal communications, electronic communications, envelopes and mailing, and classified correspondence. The appendices address specific guidelines for administrator's correspondence, White House and Congressional correspondance, Privacy Act correspondence, and foreign correspondence. Also incorporated as appendices are quick references for forms of address, compound words, and capitalization of words frequently used at NASA.

  5. Correspondencia (Correspondence).

    ERIC Educational Resources Information Center

    Brannan, Robert

    The language of Spanish correspondence possesses particular characteristics that lie somewhere between the everyday conversational style and the more formal literary style. This minicourse contains three lessons intended to enable the student to learn the letter-writing style and to write letters in Spanish. It is also intended to encourage and…

  6. Hugh E. Huxley: The Compleat Biophysicist

    PubMed Central

    Hitchcock-DeGregori, Sarah E.; Irving, Thomas C.

    2014-01-01

    The sliding filament model of muscle contraction, put forward by Hugh Huxley and Jean Hanson in 1954, is 60 years old in 2014. Formulation of the model and subsequent proof was driven by the pioneering work of Hugh Huxley (1924–2013). We celebrate Huxley’s integrative approach to the study of muscle contraction; how he persevered throughout his career, to the end of his life at 89 years, to understand at the molecular level how muscle contracts and develops force. Here we show how his life and work, with its focus on a single scientific problem, had impact far beyond the field of muscle contraction to the benefit of multiple fields of cellular and structural biology. Huxley introduced the use of x-ray diffraction to study the contraction in living striated muscle, taking advantage of the paracrystalline lattice that would ultimately allow understanding contraction in terms of single molecules. Progress required design of instrumentation with ever-increasing spatial and temporal resolution, providing the impetus for the development of synchrotron facilities used for most protein crystallography and muscle studies today. From the time of his early work, Huxley combined electron microscopy and biochemistry to understand and interpret the changes in x-ray patterns. He developed improved electron-microscopy techniques, thin sections and negative staining, that enabled answering major questions relating to the structure and organization of thick and thin filaments in muscle and the interaction of myosin with actin and its regulation. Huxley established that the ATPase domain of myosin forms the crossbridges of thick filaments that bind actin, and introduced the idea that myosin makes discrete steps on actin. These concepts form the underpinning of cellular motility, in particular the study of how myosin, kinesin, and dynein motors move on their actin and tubulin tracks, making Huxley a founder of the field of cellular motility. PMID:25296301

  7. Letters and Letter Writing.

    ERIC Educational Resources Information Center

    Frese, Millie K., Ed.

    1998-01-01

    "The Goldfinch" is a periodical that introduces young children to various facets of Iowa history. Each issue has a different theme topic and a number of articles covering diverse aspects of the topic being addressed. This issue focuses on letters and letter writing. Featured articles discuss letters that illuminate historical events. The…

  8. How a Neurologically Integrated Approach Which Teaches Sound-Symbol Correspondence and Legible Letter Formations Impacts At-Risk First Graders

    ERIC Educational Resources Information Center

    Shaw, Donita Massengill; Sundberg, Mary Lou

    2008-01-01

    The setting of this study took place in an inner city. The purpose was to determine the effectiveness of a neurologically integrated approach in teaching 43 at-risk pre-first graders their letter sounds and formations during 45-50 hours of summer school. There were four sequential phases to teaching this alphabetic approach: imagery, auditory,…

  9. Evolution and Education: Lessons from Thomas Huxley

    NASA Astrophysics Data System (ADS)

    Lyons, Sherrie Lynne

    2010-05-01

    Thomas Huxley more than anyone else was responsible for disseminating Darwin’s theory in the western world and maintained that investigating the history of life should be regarded as a purely scientific question free of theological speculation. The content and rhetorical strategy of Huxley’s defense of evolution is analyzed. Huxley argued that the classification of humans should be determined independent of any theories of origination of species. Besides providing evidence that demonstrated the close relationship between apes and humans, he also argued that a pithecoid ancestry in no way degraded humankind. In his broader defense of evolution he drew on his agnosticism to define what science could and could not explain. Theology made empirical claims and needed to be subject to the same standards of evidence as scientific claims. He maintained that even most scientific objections to evolution were religiously based. The objections to the theory fundamentally remain the same as in the nineteenth century and much can be learned from Huxley to develop effective strategies for educating the public about evolution. Huxley’s own scientific articles as well as his popular writings provide numerous examples that could be harnessed not only for the teaching of evolution, but also for understanding science as a process.

  10. Brave new world revisited revisited: Huxley's evolving view of behaviorism

    PubMed Central

    Newman, Bobby

    1992-01-01

    Aldous Huxley's Brave New World has served as a popular and powerful source of antibehavioral sentiment. Several of Huxley's works are examined in order to ascertain his true thoughts regarding behaviorism. Early in his career Huxley failed to appreciate aspects of behavioral theory (e.g., an appreciation of heredity) or the good ends to which it could be employed. Huxley's later works portrayed behaviorism in a much more positive light, and he believed that behavioral science, along with spiritual enlightenment, might help save humanity from the Brave New World he predicted. PMID:22478115

  11. Brave new world revisited revisited: Huxley's evolving view of behaviorism.

    PubMed

    Newman, B

    1992-01-01

    Aldous Huxley's Brave New World has served as a popular and powerful source of antibehavioral sentiment. Several of Huxley's works are examined in order to ascertain his true thoughts regarding behaviorism. Early in his career Huxley failed to appreciate aspects of behavioral theory (e.g., an appreciation of heredity) or the good ends to which it could be employed. Huxley's later works portrayed behaviorism in a much more positive light, and he believed that behavioral science, along with spiritual enlightenment, might help save humanity from the Brave New World he predicted.

  12. Challenging normative orthodoxies in depression: Huxley's Utopia or Dante's Inferno?

    PubMed

    Cutcliffe, John R; Lakeman, Richard

    2010-04-01

    Although there appears to be a widespread consensus that depression is a ubiquitous human experience, definitions of depression, its prevalence, and how mental health services respond to it have changed significantly over time, particularly during recent decades. Epistemological limitations notwithstanding, it is now estimated that approximately 121 million people experience depression. At the same time, it should be acknowledged that the last two decades have seen the widespread acceptance of depression as a chemical imbalance and a massive corresponding increase in the prescription of antidepressants, most notably of selective serotonin reuptake inhibitors (SSRIs). However, questions have been raised about the effectiveness and iatrogenic side effects of antidepressants; related questions have also been asked about whose interests are served by the marketing and sales of these drugs. Accordingly, this article attempts to problematize the normative orthodoxy concerning depression and creates a "space" in which an alternative can be articulated and enacted. In so doing, the article finds that the search for a world where the automatic response to depression is a pharmacological intervention not only ignores the use of alternative efficacious treatment options but may also inhibit the persons' chance to explore the meaning of their experience and thus prevent people from individual growth and personal development. Interestingly, in worlds analogous to this pharmacologically induced depression-free state, such as utopias like that in Huxley's Brave New World, no "properly conditioned citizen" is depressed or suicidal. Yet, in the same Brave New World, no one is free to suffer, to be different, or crucially, to be independent.

  13. Schizophrenia, evolution and the borders of biology: on Huxley et al.'s 1964 paper in Nature.

    PubMed

    De Bont, Raf

    2010-06-01

    In October 1964, Julian Huxley, Ernst Mayr, Humphrey Osmond and Abram Hoffer co-published a controversial paper in Nature, in which they tried to explain the persistence of schizophrenia from an evolutionary perspective. This article will elucidate how the reputed authors composed this paper to make it a strong argument for biological psychiatry. Through a close reading of their correspondence, it will furthermore clarify the elements which remained unspoken in the paper, but which were elementary in its genesis. The first was the dominance of psychoanalytical theory in (American) psychiatry--a dominance which the authors wanted to break. The second was the ongoing discussion on the boundaries of biological determinism and the desirability of a new kind of eugenics. As such, the Huxley et al. paper can be used to study the central issues of psychiatry in a pivotal era of its history.

  14. Julian Huxley, Uca pugnax and the allometric method.

    PubMed

    Packard, Gary C

    2012-02-15

    The allometric method, which often is attributed to Julian Huxley, entails fitting a straight line to logarithmic transformations of the original bivariate data and then back-transforming the resulting equation to form a power function in the arithmetic scale. Development of the technique was strongly influenced by Huxley's own research on growth by the enlarged 'crusher' claw in male fiddler crabs (Uca pugnax). Huxley reported a discontinuity in the log-log plot of chela mass vs body mass, which he interpreted as an abrupt change in relative growth of the chela at about the time crabs attain sexual maturity. My analysis of Huxley's arithmetic data indicates, however, that the discontinuity was an artifact caused by logarithmic transformation and that dynamics of growth by the crusher claw do not change at any point during development. Arithmetic data are well described by a power function fitted by nonlinear regression but not by one estimated by back-transforming a line fitted to logarithms. This finding and others like it call into question the continued reliance on the allometric method in contemporary research.

  15. A Stimulus Sampling Theory of Letter Identity and Order

    ERIC Educational Resources Information Center

    Norris, Dennis; Kinoshita, Sachiko; van Casteren, Maarten

    2010-01-01

    Early on during word recognition, letter positions are not accurately coded. Evidence for this comes from transposed-letter (TL) priming effects, in which letter strings generated by transposing two adjacent letters (e.g., "jugde") produce large priming effects, more than primes with the letters replaced in the corresponding position (e.g.,…

  16. Statistical mechanics of the Huxley-Simmons model

    NASA Astrophysics Data System (ADS)

    Caruel, M.; Truskinovsky, L.

    2016-06-01

    The chemomechanical model of Huxley and Simmons (HS) [A. F. Huxley and R. M. Simmons, Nature 233, 533 (1971), 10.1038/233533a0] provides a paradigmatic description of mechanically induced collective conformational changes relevant in a variety of biological contexts, from muscles power stroke and hair cell gating to integrin binding and hairpin unzipping. We develop a statistical mechanical perspective on the HS model by exploiting a formal analogy with a paramagnetic Ising model. We first study the equilibrium HS model with a finite number of elements and compute explicitly its mechanical and thermal properties. To model kinetics, we derive a master equation and solve it for several loading protocols. The developed formalism is applicable to a broad range of allosteric systems with mean-field interactions.

  17. Analytical solutions of the Frankenhaeuser-Huxley equations I: minimal model for backpropagation of action potentials in sparsely excitable dendrites.

    PubMed

    Poznanski, Roman R

    2004-09-01

    Hodgkin and Huxley's ionic theory of the nerve impulse embodies principles, applicable also to the impulses in vertebrate nerve fibers, as demonstrated by Bernhard Frankenhaeuser and Andrew Huxley 40 years ago. Frankenhaeuser and Huxley reformulated the classical Hodgkin-Huxley equations, in terms of electrodiffusion theory, and computed action potentials specifically for saltatory conduction in myelinated axons. In this paper, we obtain analytical solutions to the most difficult nonlinear partial differential equations in classical neurophysiology. We solve analytically the Frankenhaeuser-Huxley equations pertaining to a model of sparsely excitable, nonlinear dendrites with clusters of transiently activating, TTX-sensitive Na(+) channels, discretely distributed as point sources of inward current along a continuous (non-segmented) leaky cable structure. Each cluster or hot-spot, corresponding to a mesoscopic level description of Na(+) ion channels, includes known cumulative inactivation kinetics observed at the microscopic level. In such a third-order system, the 'recovery' variable is an electrogenic sodium-pump imbedded in the passive membrane, and the system is stabilized by the presence of a large leak conductance mediated by a composite number of ligand-gated channels permeable to monovalent cations Na(+) and K(+). In order to reproduce antidromic propagation and attenuation of action potentials, a nonlinear integral equation must be solved (in the presence of suprathreshold input, and a constant-field equation of electrodiffusion at each hot-spot with membrane gates controlling the flow of current). A perturbative expansion of the non-dimensional membrane potential (Phi) is used to obtain time-dependent analytical solutions, involving a voltage-dependent Na(+) activation (micro) and a state-dependent inactivation (eta) gating variables. It is shown that action potentials attenuate in amplitude in accordance with experimental findings, and that the spatial

  18. Models of Discourse in the Letter of Complaint

    ERIC Educational Resources Information Center

    Hartford, Beverly; Mahboob, Ahmar

    2004-01-01

    In both the Outer Circle and the Expanding Circle countries, books which provide examples of letters written in English and guidelines for writing these letters are available for students, business people, and any others who have an interest or need for writing such letters. These model letters are not only for business correspondence, but also…

  19. Memristor, Hodgkin-Huxley, and Edge of Chaos

    NASA Astrophysics Data System (ADS)

    Chua, Leon

    2013-09-01

    From a pedagogical point of view, the memristor is defined in this tutorial as any 2-terminal device obeying a state-dependent Ohm’s law. This tutorial also shows that from an experimental point of view, the memristor can be defined as any 2-terminal device that exhibits the fingerprints of ‘pinched’ hysteresis loops in the v-i plane. It also shows that memristors endowed with a continuum of equilibrium states can be used as non-volatile analog memories. This tutorial shows that memristors span a much broader vista of complex phenomena and potential applications in many fields, including neurobiology. In particular, this tutorial presents toy memristors that can mimic the classic habituation and LTP learning phenomena. It also shows that sodium and potassium ion-channel memristors are the key to generating the action potential in the Hodgkin-Huxley equations, and that they are the key to resolving several unresolved anomalies associated with the Hodgkin-Huxley equations. This tutorial ends with an amazing new result derived from the new principle of local activity, which uncovers a minuscule life-enabling ‘Goldilocks zone’, dubbed the edge of chaos, where complex phenomena, including creativity and intelligence, may emerge. From an information processing perspective, this tutorial shows that synapses are locally-passive memristors, and that neurons are made of locally-active memristors.

  20. Memristor, Hodgkin-Huxley, and edge of chaos.

    PubMed

    Chua, Leon

    2013-09-27

    From a pedagogical point of view, the memristor is defined in this tutorial as any 2-terminal device obeying a state-dependent Ohm's law. This tutorial also shows that from an experimental point of view, the memristor can be defined as any 2-terminal device that exhibits the fingerprints of 'pinched' hysteresis loops in the v-i plane. It also shows that memristors endowed with a continuum of equilibrium states can be used as non-volatile analog memories. This tutorial shows that memristors span a much broader vista of complex phenomena and potential applications in many fields, including neurobiology. In particular, this tutorial presents toy memristors that can mimic the classic habituation and LTP learning phenomena. It also shows that sodium and potassium ion-channel memristors are the key to generating the action potential in the Hodgkin-Huxley equations, and that they are the key to resolving several unresolved anomalies associated with the Hodgkin-Huxley equations. This tutorial ends with an amazing new result derived from the new principle of local activity, which uncovers a minuscule life-enabling 'Goldilocks zone', dubbed the edge of chaos, where complex phenomena, including creativity and intelligence, may emerge. From an information processing perspective, this tutorial shows that synapses are locally-passive memristors, and that neurons are made of locally-active memristors.

  1. Response of autaptic Hodgkin-Huxley neuron with noise to subthreshold sinusoidal signals

    NASA Astrophysics Data System (ADS)

    Wang, Hengtong; Chen, Yong

    2016-11-01

    In this work, we investigated the response of a stochastic Hodgkin-Huxley (HH) neuron with an autapse to subthreshold sinusoidal signals. It is found that the autapse not only adjusts the stochastic responses, but also improves the detection of subthreshold signals. In the case of weak noise, the autapse facilitates the response of neuron to the subthreshold sinusoidal signals with a small parameter region in tdelay- ω space. The increased noise intensity enlarges this parameter region and increases the corresponding response frequency in such range. As the autaptic intensity increases, however, this parameter region shrunks. We also observed that there is an optimal range of the delay time of autapse, within which the stochastic HH neuron fires action potentials with high frequency. The corresponding response spike train for the optimal delay time is nearly a regular sequence with the interspike intervals approximated to the delay time. The current results reveal a novel resonance phenomenon facilitated by autapse, named autaptic delay-induced coherence resonance.

  2. Jules Janssen's in and out correspondence

    NASA Astrophysics Data System (ADS)

    Launay, Françoise

    2001-10-01

    When she died in 1924, Miss Antoinette Janssen, the only daughter of Jules Janssen (1824-1907), bequeathed all the letters her parents had received at home to the Library of the Institut de France in Paris. That correspondence is still preserved there, in guard-books containing about 1700 letters, the transcription of which is in progress. It is not so easy to trace the outgoing letters and transcribe them, and any help would be much appreciated!

  3. Correspondence analysis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Correspondence analysis is a powerful exploratory multivariate technique for categorical variables with many levels. It is a data analysis tool that characterizes associations between levels of 2 or more categorical variables using graphical representations of the information in a contingency table...

  4. Correspondence Journals: Talk That Matters

    ERIC Educational Resources Information Center

    Bloem, Patricia L.

    2004-01-01

    Correspondence journals between adults and elementary-school students promote child-centered discussion and learning that is often squeezed out of the curricula. Through an extended example of an exchange of letters between a fifth-grade classroom, including several English-language learners and a university classroom of preservice teachers, the…

  5. On universality in human correspondence activity.

    PubMed

    Malmgren, R Dean; Stouffer, Daniel B; Campanharo, Andriana S L O; Amaral, Luís A Nunes

    2009-09-25

    The identification and modeling of patterns of human activity have important ramifications for applications ranging from predicting disease spread to optimizing resource allocation. Because of its relevance and availability, written correspondence provides a powerful proxy for studying human activity. One school of thought is that human correspondence is driven by responses to received correspondence, a view that requires a distinct response mechanism to explain e-mail and letter correspondence observations. We demonstrate that, like e-mail correspondence, the letter correspondence patterns of 16 writers, performers, politicians, and scientists are well described by the circadian cycle, task repetition, and changing communication needs. We confirm the universality of these mechanisms by rescaling letter and e-mail correspondence statistics to reveal their underlying similarity.

  6. Einstein/Roosevelt Letters: A Unit.

    ERIC Educational Resources Information Center

    Bodle, Walter S.

    1985-01-01

    The letters in this unit of study intended for secondary students are facsimile reproductions of the correspondence between Albert Einstein and President Roosevelt on the possibility of constructing an atomic bomb. Classroom activities are also suggested. (RM)

  7. Spontaneous spiking in an autaptic Hodgkin-Huxley setup

    NASA Astrophysics Data System (ADS)

    Li, Yunyun; Schmid, Gerhard; Hänggi, Peter; Schimansky-Geier, Lutz

    2010-12-01

    The effect of intrinsic channel noise is investigated for the dynamic response of a neuronal cell with a delayed feedback loop. The loop is based on the so-called autapse phenomenon in which dendrites establish connections not only to neighboring cells but also to its own axon. The biophysical modeling is achieved in terms of a stochastic Hodgkin-Huxley model containing such a built in delayed feedback. The fluctuations stem from intrinsic channel noise, being caused by the stochastic nature of the gating dynamics of ion channels. The influence of the delayed stimulus is systematically analyzed with respect to the coupling parameter and the delay time in terms of the interspike interval histograms and the average interspike interval. The delayed feedback manifests itself in the occurrence of bursting and a rich multimodal interspike interval distribution, exhibiting a delay-induced reduction in the spontaneous spiking activity at characteristic frequencies. Moreover, a specific frequency-locking mechanism is detected for the mean interspike interval.

  8. The ISI distribution of the stochastic Hodgkin-Huxley neuron.

    PubMed

    Rowat, Peter F; Greenwood, Priscilla E

    2014-01-01

    The simulation of ion-channel noise has an important role in computational neuroscience. In recent years several approximate methods of carrying out this simulation have been published, based on stochastic differential equations, and all giving slightly different results. The obvious, and essential, question is: which method is the most accurate and which is most computationally efficient? Here we make a contribution to the answer. We compare interspike interval histograms from simulated data using four different approximate stochastic differential equation (SDE) models of the stochastic Hodgkin-Huxley neuron, as well as the exact Markov chain model simulated by the Gillespie algorithm. One of the recent SDE models is the same as the Kurtz approximation first published in 1978. All the models considered give similar ISI histograms over a wide range of deterministic and stochastic input. Three features of these histograms are an initial peak, followed by one or more bumps, and then an exponential tail. We explore how these features depend on deterministic input and on level of channel noise, and explain the results using the stochastic dynamics of the model. We conclude with a rough ranking of the four SDE models with respect to the similarity of their ISI histograms to the histogram of the exact Markov chain model.

  9. Stability of synchronous oscillations in a system of Hodgkin-Huxley neurons with delayed diffusive and pulsed coupling

    NASA Astrophysics Data System (ADS)

    Rossoni, Enrico; Chen, Yonghong; Ding, Mingzhou; Feng, Jianfeng

    2005-06-01

    We study the synchronization dynamics for a system of two Hodgkin-Huxley (HH) neurons coupled diffusively or through pulselike interactions. By calculating the maximum transverse Lyapunov exponent, we found that, with diffusive coupling, there are three regions in the parameter space, corresponding to qualitatively distinct behaviors of the coupled dynamics. In particular, the two neurons can synchronize in two regions and desynchronize in the third. When excitatory and inhibitory pulse coupling is considered, we found that synchronized dynamics becomes more difficult to achieve in the sense that the parameter regions where the synchronous state is stable are smaller. Numerical simulations of the coupled system are presented to validate these results. The stability of a network of coupled HH neurons is then analyzed and the stability regions in the parameter space are exactly obtained.

  10. Stability of synchronous oscillations in a system of Hodgkin-Huxley neurons with delayed diffusive and pulsed coupling.

    PubMed

    Rossoni, Enrico; Chen, Yonghong; Ding, Mingzhou; Feng, Jianfeng

    2005-06-01

    We study the synchronization dynamics for a system of two Hodgkin-Huxley (HH) neurons coupled diffusively or through pulselike interactions. By calculating the maximum transverse Lyapunov exponent, we found that, with diffusive coupling, there are three regions in the parameter space, corresponding to qualitatively distinct behaviors of the coupled dynamics. In particular, the two neurons can synchronize in two regions and desynchronize in the third. When excitatory and inhibitory pulse coupling is considered, we found that synchronized dynamics becomes more difficult to achieve in the sense that the parameter regions where the synchronous state is stable are smaller. Numerical simulations of the coupled system are presented to validate these results. The stability of a network of coupled HH neurons is then analyzed and the stability regions in the parameter space are exactly obtained.

  11. Principal Dynamic Mode Analysis of the Hodgkin–Huxley Equations

    PubMed Central

    Eikenberry, Steffen E.; Marmarelis, Vasilis Z.

    2015-01-01

    We develop an autoregressive model framework based on the concept of Principal Dynamic Modes (PDMs) for the process of action potential (AP) generation in the excitable neuronal membrane described by the Hodgkin–Huxley (H–H) equations. The model's exogenous input is injected current, and whenever the membrane potential output exceeds a specified threshold, it is fed back as a second input. The PDMs are estimated from the previously developed Nonlinear Autoregressive Volterra (NARV) model, and represent an efficient functional basis for Volterra kernel expansion. The PDM-based model admits a modular representation, consisting of the forward and feedback PDM bases as linear filterbanks for the exogenous and autoregressive inputs, respectively, whose outputs are then fed to a static nonlinearity composed of polynomials operating on the PDM outputs and cross-terms of pair-products of PDM outputs. A two-step procedure for model reduction is performed: first, influential subsets of the forward and feedback PDM bases are identified and selected as the reduced PDM bases. Second, the terms of the static nonlinearity are pruned. The first step reduces model complexity from a total of 65 coefficients to 27, while the second further reduces the model coefficients to only eight. It is demonstrated that the performance cost of model reduction in terms of out-of-sample prediction accuracy is minimal. Unlike the full model, the eight coefficient pruned model can be easily visualized to reveal the essential system components, and thus the data-derived PDM model can yield insight into the underlying system structure and function. PMID:25630480

  12. Principal dynamic mode analysis of the Hodgkin-Huxley equations.

    PubMed

    Eikenberry, Steffen E; Marmarelis, Vasilis Z

    2015-03-01

    We develop an autoregressive model framework based on the concept of Principal Dynamic Modes (PDMs) for the process of action potential (AP) generation in the excitable neuronal membrane described by the Hodgkin-Huxley (H-H) equations. The model's exogenous input is injected current, and whenever the membrane potential output exceeds a specified threshold, it is fed back as a second input. The PDMs are estimated from the previously developed Nonlinear Autoregressive Volterra (NARV) model, and represent an efficient functional basis for Volterra kernel expansion. The PDM-based model admits a modular representation, consisting of the forward and feedback PDM bases as linear filterbanks for the exogenous and autoregressive inputs, respectively, whose outputs are then fed to a static nonlinearity composed of polynomials operating on the PDM outputs and cross-terms of pair-products of PDM outputs. A two-step procedure for model reduction is performed: first, influential subsets of the forward and feedback PDM bases are identified and selected as the reduced PDM bases. Second, the terms of the static nonlinearity are pruned. The first step reduces model complexity from a total of 65 coefficients to 27, while the second further reduces the model coefficients to only eight. It is demonstrated that the performance cost of model reduction in terms of out-of-sample prediction accuracy is minimal. Unlike the full model, the eight coefficient pruned model can be easily visualized to reveal the essential system components, and thus the data-derived PDM model can yield insight into the underlying system structure and function.

  13. Developmental letter position dyslexia.

    PubMed

    Friedmann, Naama; Rahamim, Einav

    2007-09-01

    Letter position dyslexia (LPD) is a peripheral dyslexia that causes errors of letter order within words. So far, only cases of acquired LPD have been reported. This study presents selective LPD in its developmental form, via the testing of II Hebrew-speaking individuals with developmental dyslexia. The study explores the types of errors and effects on reading in this dyslexia, using a variety of tests: reading aloud, lexical decision, same-different decision, definition and letter naming. The findings indicate that individuals with developmental LPD have a deficit in the letter position encoding function of the orthographic visual analyser, which leads to underspecification of letter position within words. Letter position errors occur mainly in adjacent middle letters, when the error creates another existing word. The participants did not show an output deficit or phonemic awareness deficit. The selectivity of the deficit, causing letter position errors but no letter identity errors and no migrations between words, supports the existence of letter position encoding function as separate from letter identification and letter-to-word binding.

  14. RED-LETTER DAYS

    EPA Science Inventory

    The word "red-letter" is an adjective meaning "of special significance." It's origin is from the practice of marking Christian holy days in red letters on calendars. The "red-letter days" to which I refer occurred while I was a graduate student of ...

  15. Van: An Open Letter

    ERIC Educational Resources Information Center

    Tieman, John Samuel

    2011-01-01

    This essay is an open letter from a classroom teacher to a concerned citizen. The letter lists a variety of problems caused largely by standardization and the more corrosive effects of positivism. Many of these problems are unknown to those outside the immediate school setting. While the letter focuses on a specific setting, an inner city school…

  16. Learning to write letters: examination of student and letter factors.

    PubMed

    Puranik, Cynthia S; Petscher, Yaacov; Lonigan, Christopher J

    2014-12-01

    Learning to write the letters of the alphabet is an important part of learning how to write conventionally. In this study, we investigated critical factors in the development of letter-writing skills using exploratory item response models to simultaneously account for variance in responses due to differences between students and between letters. Letter-writing skills were assessed in 415 preschool children aged 3 to 5 years. At the student level, we examined the contribution of letter-name knowledge, letter-sound knowledge, and phonological awareness to letter-writing skills. At the letter level, we examined seven intrinsic and extrinsic factors in understanding how preschool children learn to write alphabet letters: first letter of name, letters in name, letter order, textual frequency, number of strokes, symmetry, and letter type. Results indicated that variation in letter-writing skills was accounted for more by differences between students rather than by differences between letters, with most of the variability accounted for by letter-name knowledge and age. Although significant, the contribution of letter-sound knowledge and phonological awareness was relatively small. Student-level mechanisms underlying the acquisition of letter-writing skills are similar to the mechanisms underlying the learning of letter sounds. However, letter characteristics, which appear to play a major role in the learning of letter names and letter sounds, did not appear to influence learning how to write letters in a substantial way. The exception was if the letter was in the child's name.

  17. T.H. Huxley's criticism of German cell theory: an epigenetic and physiological interpretation of cell structure.

    PubMed

    Richmond, M L

    2000-01-01

    In 1853, the young Thomas Henry Huxley published a long review of German cell theory in which he roundly criticized the basic tenets of the Schleiden-Schwann model of the cell. Although historians of cytology have dismissed Huxley's criticism as based on an erroneous interpretation of cell physiology, the review is better understood as a contribution to embryology. "The Cell-theory" presents Huxley's "epigenetic" interpretation of histological organization emerging from changes in the protoplasm to replace the "preformationist" cell theory of Schleiden and Schwann (as modified by Albert von Kolliker), which posited the nucleus as the seat of organic vitality. Huxley's views influenced a number of British biologists, who continued to oppose German cell theory well into the twentieth century. Yet Huxley was pivotal in introducing the new German program of "scientific zoology" to Britain in the early 1850s, championing its empiricist methodology as a means to enact broad disciplinary and institutional reforms in British natural history.

  18. An investigation of the stochastic Hodgkin-Huxley models under noisy rate functions.

    PubMed

    Güler, Marifi

    2013-09-01

    The effects of ion channel fluctuations on the transmembrane voltage activity are potentially profound in small-size excitable membrane patches. Different groups have extended Hodgkin-Huxley equations into stochastic differential equations to capture the effects of ion channel noise analytically (Fox & Lu, 1994; Linaro, Storace, & Giugliano, 2011; Güler, 2013). Studies have shown that the accuracy of spiking statistics by Fox and Lu's model does not match well with the corresponding statistics from the exact microscopic simulations. The models of both Linaro et al. and Güler, however, were found to produce highly accurate statistics. Here we extend the examination of these models to the case in which the rate functions for the opening and closing of gates are under the influence of noise. For that purpose, the usual rate functions are accompanied additively by Ornstein-Uhlenbeck-type stochastic angular variables. Moreover, we argue that the existence of such noise in the rate functions is a plausible physiological phenomenon for finite-size membranes. It is observed that the presence of noise in the rates is not effective on the degree of inaccuracies within the Fox and Lu model. Güler model's accuracy is found to remain high as in the case of noise free rates. But the performance of Linaro et al.'s model is seen to degrade seriously with the increasing strength of the introduced rate function noise. We attribute this failure of Linaro et al.'s model to the use of the covariance function of open channels at the steady state, in its derivation.

  19. Mud, Blood, and Bullet Holes: Teaching History with War Letters

    ERIC Educational Resources Information Center

    Carroll, Andrew

    2013-01-01

    From handwritten letters of the American Revolution to typed emails from Iraq and Afghanistan, correspondence from U.S. troops offers students deep insight into the specific conflicts and experiences of soldiers. Over 100,000 correspondences have been donated to the Legacy Project, a national initiative launched in 1998 to preserve war letters by…

  20. Tunicates: exploring the sea shores and roaming the open ocean. A tribute to Thomas Huxley

    PubMed Central

    Lemaire, Patrick; Piette, Jacques

    2015-01-01

    This review is a tribute to the remarkable contributions of Thomas Huxley to the biology of tunicates, the likely sister group of vertebrates. In 1851, the great biologist and philosopher published two landmark papers on pelagic tunicates in the Philosophical Transactions of the Royal Society. They were dedicated to the description of the adult anatomy and life cycle of thaliaceans and appendicularians, the pelagic relatives of ascidians. In the first part of this review, we discuss the novel anatomical observations and evolutionary hypotheses made by Huxley, which would have a lasting influence on tunicate biology. We also briefly comment on the more philosophical reflections of Huxley on individuality. In the second part, we stress the originality and relevance of past and future studies of tunicates in the resolution of major biological issues. In particular, we focus on the complex relationship between genotype and phenotype and the phenomenon of developmental system drift. We propose that more than 150 years after Huxley's papers, tunicate embryos are still worth studying in their own right, independently of their evolutionary proximity to vertebrates, as they provide original and crucial insights into the process of animal evolution. Tunicates are still at the forefront of biological research. PMID:26085517

  1. The costs of being a restless intellect: Julian Huxley's popular and scientific career in the 1920s.

    PubMed

    Erlingsson, Steindór J

    2009-06-01

    Julian Huxley's (1887-1975) contribution to twentieth-century biology and science popularisation is well documented. What has not been appreciated so far is that despite Huxley's eminence as a public scientific figure and the part that he played in the rise of experimental zoology in Britain in the 1920s, his own research was often heavily criticised in this period by his colleagues. This resulted in numerous difficulties in getting his scientific research published in the early 1920s. At this time, Huxley started his popular science career. Huxley's friends criticised him for engaging in this actively and attributed the publication difficulties to the time that he allocated to popular science. The cause might also have its roots in his self-professed inability to delve deeply into the particularities of research. This affected Huxley's standing in the scientific community and seems to have contributed to the fact that Huxley failed twice in the late 1920s to be elected to the Royal Society. This picture undermines to some extent Peter J. Bowler's recent portrayal of Huxley as a science populariser.

  2. The what and where of adding channel noise to the Hodgkin-Huxley equations.

    PubMed

    Goldwyn, Joshua H; Shea-Brown, Eric

    2011-11-01

    Conductance-based equations for electrically active cells form one of the most widely studied mathematical frameworks in computational biology. This framework, as expressed through a set of differential equations by Hodgkin and Huxley, synthesizes the impact of ionic currents on a cell's voltage--and the highly nonlinear impact of that voltage back on the currents themselves--into the rapid push and pull of the action potential. Later studies confirmed that these cellular dynamics are orchestrated by individual ion channels, whose conformational changes regulate the conductance of each ionic current. Thus, kinetic equations familiar from physical chemistry are the natural setting for describing conductances; for small-to-moderate numbers of channels, these will predict fluctuations in conductances and stochasticity in the resulting action potentials. At first glance, the kinetic equations provide a far more complex (and higher-dimensional) description than the original Hodgkin-Huxley equations or their counterparts. This has prompted more than a decade of efforts to capture channel fluctuations with noise terms added to the equations of Hodgkin-Huxley type. Many of these approaches, while intuitively appealing, produce quantitative errors when compared to kinetic equations; others, as only very recently demonstrated, are both accurate and relatively simple. We review what works, what doesn't, and why, seeking to build a bridge to well-established results for the deterministic equations of Hodgkin-Huxley type as well as to more modern models of ion channel dynamics. As such, we hope that this review will speed emerging studies of how channel noise modulates electrophysiological dynamics and function. We supply user-friendly MATLAB simulation code of these stochastic versions of the Hodgkin-Huxley equations on the ModelDB website (accession number 138950) and http://www.amath.washington.edu/~etsb/tutorials.html.

  3. Metamorphopsia and letter recognition.

    PubMed

    Wiecek, Emily; Dakin, Steven C; Bex, Peter

    2014-12-01

    Acuity is the most commonly used measure of visual function, and reductions in acuity are associated with most eye diseases. Metamorphopsia--a perceived distortion of visual space--is another common symptom of visual impairment and is currently assessed qualitatively using Amsler (1953) charts. In order to quantify the impact of metamorphopsia on acuity, we measured the effect of physical spatial distortion on letter recognition. Following earlier work showing that letter recognition is tuned to specific spatial frequency (SF) channels, we hypothesized that the effect of distortion might depend on the spatial scale of visual distortion just as it depends on the spatial scale of masking noise. Six normally sighted observers completed a 26 alternate forced choice (AFC) Sloan letter identification task at five different viewing distances, and the letters underwent different levels of spatial distortion. Distortion was controlled using spatially band-pass filtered noise that spatially remapped pixel locations. Noise was varied over five spatial frequencies and five magnitudes. Performance was modeled with logistic regression and worsened linearly with increasing distortion magnitude and decreasing letter size. We found that retinal SF affects distortion at midrange frequencies and can be explained with the tuning of a basic contrast sensitivity function, while object-centered distortion SF follows a similar pattern of letter object recognition sensitivity and is tuned to approximately three cycles per letter (CPL). The interaction between letter size and distortion makes acuity an unreliable outcome for metamorphopsia assessment.

  4. From Shape to Letters.

    ERIC Educational Resources Information Center

    Schiller, Hillel A.

    In order to make letter shape recognition an integral part of perception training, the use of the line in its two basic shapes is proposed. Letter shapes may seem exceedingly complex linear shapes to young minds. Thus instead of instruction in configuration, instruction involving transformational activities to manipulate and create the…

  5. Metamorphopsia and letter recognition

    PubMed Central

    Wiecek, Emily; Dakin, Steven C.; Bex, Peter

    2014-01-01

    Acuity is the most commonly used measure of visual function, and reductions in acuity are associated with most eye diseases. Metamorphopsia—a perceived distortion of visual space—is another common symptom of visual impairment and is currently assessed qualitatively using Amsler (1953) charts. In order to quantify the impact of metamorphopsia on acuity, we measured the effect of physical spatial distortion on letter recognition. Following earlier work showing that letter recognition is tuned to specific spatial frequency (SF) channels, we hypothesized that the effect of distortion might depend on the spatial scale of visual distortion just as it depends on the spatial scale of masking noise. Six normally sighted observers completed a 26 alternate forced choice (AFC) Sloan letter identification task at five different viewing distances, and the letters underwent different levels of spatial distortion. Distortion was controlled using spatially band-pass filtered noise that spatially remapped pixel locations. Noise was varied over five spatial frequencies and five magnitudes. Performance was modeled with logistic regression and worsened linearly with increasing distortion magnitude and decreasing letter size. We found that retinal SF affects distortion at midrange frequencies and can be explained with the tuning of a basic contrast sensitivity function, while object-centered distortion SF follows a similar pattern of letter object recognition sensitivity and is tuned to approximately three cycles per letter (CPL). The interaction between letter size and distortion makes acuity an unreliable outcome for metamorphopsia assessment. PMID:25453116

  6. The time course of visual influences in letter recognition.

    PubMed

    Madec, Sylvain; Le Goff, Kévin; Riès, Stéphanie K; Legou, Thierry; Rousselet, Guillaume; Courrieu, Pierre; Alario, F-Xavier; Grainger, Jonathan; Rey, Arnaud

    2016-06-01

    This study builds on a specific characteristic of letters of the Roman alphabet-namely, that each letter name is associated with two visual formats, corresponding to their uppercase and lowercase versions. Participants had to read aloud the names of single letters, and event-related potentials (ERPs) for six pairs of visually dissimilar upper- and lowercase letters were recorded. Assuming that the end product of processing is the same for upper- and lowercase letters sharing the same vocal response, ERPs were compared backward, starting from the onset of articulatory responses, and the first significant divergence was observed 120 ms before response onset. Given that naming responses were produced at around 414 ms, on average, these results suggest that letter processing is influenced by visual information until 294 ms after stimulus onset. This therefore provides new empirical evidence regarding the time course and interactive nature of visual letter perception processes.

  7. Which Children Benefit from Letter Names in Learning Letter Sounds?

    ERIC Educational Resources Information Center

    Treiman, Rebecca; Pennington, Bruce F.; Shriberg, Lawrence D.; Boada, Richard

    2008-01-01

    Typical U.S. children use their knowledge of letters' names to help learn the letters' sounds. They perform better on letter sound tests with letters that have their sounds at the beginnings of their names, such as v, than with letters that have their sounds at the ends of their names, such as m, and letters that do not have their sounds in their…

  8. Controlling the onset of Hopf bifurcation in the Hodgkin-Huxley model

    NASA Astrophysics Data System (ADS)

    Xie, Yong; Chen, Luonan; Kang, Yan Mei; Aihara, Kazuyuki

    2008-06-01

    It is a challenging problem to establish safe and simple therapeutic methods for various complicated diseases of the nervous system, particularly dynamical diseases such as epilepsy, Alzheimer’s disease, and Parkinson’s disease. From the viewpoint of nonlinear dynamical systems, a dynamical disease can be considered to be caused by a bifurcation induced by a change in the values of one or more regulating parameter. Therefore, the theory of bifurcation control may have potential applications in the diagnosis and therapy of dynamical diseases. In this study, we employ a washout filter-aided dynamic feedback controller to control the onset of Hopf bifurcation in the Hodgkin-Huxley (HH) model. Specifically, by the control scheme, we can move the Hopf bifurcation to a desired point irrespective of whether the corresponding steady state is stable or unstable. In other words, we are able to advance or delay the Hopf bifurcation, so as to prevent it from occurring in a certain range of the externally applied current. Moreover, we can control the criticality of the bifurcation and regulate the oscillation amplitude of the bifurcated limit cycle. In the controller, there are only two terms: the linear term and the nonlinear cubic term. We show that while the former determines the location of the Hopf bifurcation, the latter regulates the criticality of the Hopf bifurcation. According to the conditions of the occurrence of Hopf bifurcation and the bifurcation stability coefficient, we can analytically deduce the linear term and the nonlinear cubic term, respectively. In addition, we also show that mixed-mode oscillations (MMOs), featuring slow action potential generation, which are frequently observed in both experiments and models of chemical and biological systems, appear in the controlled HH model. It is well known that slow firing rates in single neuron models could be achieved only by type-I neurons. However, the controlled HH model is still classified as a type

  9. Launch of Zoological Letters.

    PubMed

    Fukatsu, Takema; Kuratani, Shigeru

    2016-02-01

    A new open-access journal, Zoological Letters, was launched as a sister journal to Zoological Science, in January 2015. The new journal aims at publishing topical papers of high quality from a wide range of basic zoological research fields. This review highlights the notable reviews and research articles that have been published in the first year of Zoological Letters, providing an overview on the current achievements and future directions of the journal.

  10. Past as Prediction: Newcomb, Huxley, The Eclipse of Thales, and The Power of Science

    NASA Astrophysics Data System (ADS)

    Stanley, Matthew

    2009-12-01

    The ancient eclipse of Thales was an important, if peculiar, focus of scientific attention in the 19th century. Victorian-era astronomers first used it as data with which to calibrate their lunar theories, but its status became strangely malleable as the century progressed. The American astronomer Simon Newcomb re-examined the eclipse and rejected it as the basis for lunar theory. But strangely, it was the unprecedented accuracy of Newcomb's calculations that led the British biologist T.H. Huxley to declare the eclipse to be the quintessential example of the power of science. Huxley argued that astronomy's ability to create "retrospective prophecy” showed how scientific reasoning was superior to religion (and incidentally, helped support Darwin's theories). Both Newcomb and Huxley declared that prediction (of past and future) was what gave science its persuasive power. The eclipse of Thales's strange journey through Victorian astronomy reveals how these two influential scientists made the case for the social and cultural authority of science.

  11. Copies of clinic letters to the family.

    PubMed

    Bartle, D G; Diskin, L; Finlay, F

    2004-11-01

    In April 2004 guidelines were introduced advising that letters to the GP should be copied to parents of young people. A study was carried out to ascertain the views of young people and their parents as to who they felt should receive correspondence after an outpatient appointment.

  12. Stochastic resonance, coherence resonance, and spike timing reliability of Hodgkin-Huxley neurons with ion-channel noise

    NASA Astrophysics Data System (ADS)

    Yu, Haitao; Galán, Roberto F.; Wang, Jiang; Cao, Yibin; Liu, Jing

    2017-04-01

    The random transitions of ion channels between open and closed states are a major source of noise in neurons. In this study, we investigate the stochastic dynamics of a single Hodgkin-Huxley (HH) neuron with realistic, physiological channel noise, which depends on the channel number and the voltage potential of the membrane. Without external input, the stochastic HH model can generate spontaneous spikes induced by ion-channel noise, and the variability of inter-spike intervals attains a minimum for an optimal membrane area, a phenomenon known as coherence resonance. When a subthreshold periodic input current is added, the neuron can optimally detect the input frequency for an intermediate membrane area, corresponding to the phenomenon of stochastic resonance. We also investigate spike timing reliability of neuronal responses to repeated presentations of the same stimulus with different realizations of channel noise. We show that, with increasing membrane area, the reliability of neuronal response decreases for subthreshold periodic inputs, and attains a minimum for suprathreshold inputs. Furthermore, Arnold tongues of high reliability arise in a two-dimensional plot of frequency and amplitude of the sinusoidal input current, resulting from the resonance effect of spike timing reliability.

  13. Neural substrates of sensorimotor processes: letter writing and letter perception

    PubMed Central

    James, Karin H.

    2015-01-01

    Writing and perceiving letters are thought to share similar neural substrates; however, what constitutes a neural representation for letters is currently debated. One hypothesis is that letter representation develops from sensorimotor experience resulting in an integrated set of modality-specific regions, whereas an alternative account suggests that letter representations may be abstract, independent of modality. Studies reviewed suggest that letter representation consists of a network of modality-responsive brain regions that may include an abstract component. PMID:26203115

  14. Letter Recognition and Sound Identification.

    ERIC Educational Resources Information Center

    Prior, Jennifer

    This lesson, which is most appropriate for kindergartners, reviews letter names and their sounds through a group letter recognition activity, a picture book activity, and alphabet practice with several online activities. During three 30-minute sessions, students will: identify the letters of the alphabet; identify the sounds of letters; identify…

  15. Temporal processing deficits in letter-by-letter reading.

    PubMed

    Ingles, Janet L; Eskes, Gail A

    2007-01-01

    Theories of the cognitive impairment underlying letter-by-letter reading vary widely, including prelexical and lexical level deficits. One prominent prelexical account proposes that the disorder results from difficulty in processing multiple letters simultaneously. We investigated whether this deficit extends to letters presented in rapid temporal succession. A letter-by-letter reader, G.M., was administered a rapid serial visual presentation task that has been used widely to study the temporal processing characteristics of the normal visual system. Comparisons were made to a control group of 6 brain-damaged individuals without reading deficits. Two target letters were embedded at varying temporal positions in a stream of rapidly presented single digits. After each stream, the identities of the two letters were reported. G.M. required an extended period of time after he had processed one letter before he was able to reliably identify a second letter, relative to the controls. In addition, G.M.'s report of the second letter was most impaired when it immediately followed the first letter, a pattern not seen in the controls, indicating that G.M. had difficulty processing the two items together. These data suggest that a letter-by-letter reading strategy may be adopted to help compensate for a deficit in the temporal processing of letters.

  16. Stochastic sensitivity analysis of noise-induced suppression of firing and giant variability of spiking in a Hodgkin-Huxley neuron model.

    PubMed

    Bashkirtseva, Irina; Neiman, Alexander B; Ryashko, Lev

    2015-05-01

    We study the stochastic dynamics of a Hodgkin-Huxley neuron model in a regime of coexistent stable equilibrium and a limit cycle. In this regime, noise may suppress periodic firing by switching the neuron randomly to a quiescent state. We show that at a critical value of the injected current, the mean firing rate depends weakly on noise intensity, while the neuron exhibits giant variability of the interspike intervals and spike count. To reveal the dynamical origin of this noise-induced effect, we develop the stochastic sensitivity analysis and use the Mahalanobis metric for this four-dimensional stochastic dynamical system. We show that the critical point of giant variability corresponds to the matching of the Mahalanobis distances from attractors (stable equilibrium and limit cycle) to a three-dimensional surface separating their basins of attraction.

  17. Learning to recognize letters in the periphery: Effects of repeated exposure, letter frequency, and letter complexity

    PubMed Central

    Husk, Jesse S.; Yu, Deyue

    2017-01-01

    Patients with central vision loss must rely on their peripheral vision for reading. Unfortunately, limitations of peripheral vision, such as crowding, pose significant challenges to letter recognition. As a result, there is a need for developing effective training methods for improving crowded letter recognition in the periphery. Several studies have shown that extensive practice with letter stimuli is beneficial to peripheral letter recognition. Here, we explore stimulus-related factors that might influence the effectiveness of peripheral letter recognition training. Specifically, we examined letter exposure (number of letter occurrences), frequency of letter use in English print, and letter complexity and evaluated their contributions to the amount of improvement observed in crowded letter recognition following training. We analyzed data collected across a range of training protocols. Using linear regression, we identified the best-fitting model and observed that all three stimulus-related factors contributed to improvement in peripheral letter recognition with letter exposure being the most important factor. As an important explanatory variable, pretest accuracy was included in the model as well to avoid estimate biases and was shown to have influence on the relationship between training improvement and letter exposure. When developing training protocols for peripheral letter recognition, it may be beneficial to not only consider the overall length of training, but also to tailor the number of stimulus occurrences for each letter according to its initial performance level, frequency, and complexity. PMID:28265651

  18. Epistolary and Emotional Education: The Letters of an Irish Father to His Daughter, 1747-1752

    ERIC Educational Resources Information Center

    Ruberg, Willemijn

    2008-01-01

    The letters Bishop Edward Synge (1691-1762) wrote to his daughter Alicia (1733-1807) in 1747-1752 are discussed to show how correspondence from a father to a daughter could be used to teach a teenage girl how to spell and write letters. Moreover, these letters are an excellent source to show how emotional behaviour was taught. Instructions on…

  19. Letters and American Literacy.

    ERIC Educational Resources Information Center

    Kevis, David E.

    The work itself should help a person who is going to teach reading and writing. Practical suggestions are offered in the final two chapters, while the opening three give intellectual perspectives. A theme binds the work of letting the consciousness of writing as a visual system be increased and of breaking the spell by which letter phonetics can…

  20. Inside the Letter

    ERIC Educational Resources Information Center

    Duke, Roger; Graham, Alan

    2007-01-01

    In this article, the authors describe how a Java applet can help to build learners' intuitions about basic ideas of algebra. "Matchbox Algebra" is a Java applet the authors have designed to enable learners to grasp a key idea in learning algebra: that the letter "x" may be thought of as representing an as-yet-unknown number. They describe the…

  1. The Fuzzy Scarlet Letter

    ERIC Educational Resources Information Center

    Pallas, Aaron M.

    2012-01-01

    Critics of the public release of teacher evaluation scores sometimes liken these ratings to the scarlet letter worn by Hester Prynne in Nathaniel Hawthorne's classic novel. The comparison is apt. But public school teachers who are subjected to public shaming because of their students' test scores can rarely expect the opportunities for redemption…

  2. Letters in this Issue

    NASA Astrophysics Data System (ADS)

    1998-01-01

    Reforming the General Chemistry Textbook individual letters by Edward T. Samulski; Stephen J. Hawkes; Stephen J. Fisher; J. Stephen Hartman; A. R. H. Cole; Stanley Pine, Ronald Archer, and Herbert Kaesz; Jimmy Reeves; Robert Hill; and Brock Spencer, C. Bradley Moore and Nedah Rose. Re: article by R. J. Gillespie The author replies

  3. Harvard Education Letter, 1999.

    ERIC Educational Resources Information Center

    Graves-Desai, Kelly, Ed.

    1999-01-01

    This document is comprised of the six issues in volume 15 of the Harvard Education Letter, a bimonthly newsletter addressing current issues in elementary and secondary education. Articles in this volume include the following: (1) January-February--"Retention vs. Social Promotion: Schools Search for Alternatives" (Kelly), and "School…

  4. Harvard Education Letter, 2002.

    ERIC Educational Resources Information Center

    Gordon, David T., Editor

    2002-01-01

    This document is comprised of the 6 issues in volume 18 of the Harvard Education Letter, a bimonthly newsletter addressing current issues in elementary and secondary education. Articles in this volume include the following: (1) January/February--"Curriculum Access in the Digital Age" (David T. Gordon) and "Using Charters To Improve…

  5. Letter to Doxiadis

    ERIC Educational Resources Information Center

    Fuller, Buckminster

    1969-01-01

    The second half of a lengthy letter to Dr. Constantine Doxiadis (published in full in Main Currents in Modern Thought, XXV, March-April 1969) summarizes Buckminster Fuller's personal reflections on the impact of industrialization and on the effect of technological change in uniting mankind. (MF)

  6. Harvard Education Letter, 2001.

    ERIC Educational Resources Information Center

    Gordon, David, T., Ed.

    2001-01-01

    This document is comprised of the six issues in volume 17 of the Harvard Education Letter, a bimonthly newsletter addressing current issues in elementary and secondary education. Articles in this volume include the following: (1) January-February--"Charters and Districts: Three Stages in an Often Rocky Relationship" (Kelly) and "'We…

  7. Five Long Letters.

    ERIC Educational Resources Information Center

    Bone, Eric

    1990-01-01

    Describes the life of former Louisiana governor Huey Long through five fictitious letters. Discusses Long's experiences as a state public service commissioner, governor, and senator. Attributes Long's assassination to his killer's personal motives. Concludes that Long's life showed how much personal power could be gained even in a democracy. (SG)

  8. Channel noise effects on first spike latency of a stochastic Hodgkin-Huxley neuron

    NASA Astrophysics Data System (ADS)

    Maisel, Brenton; Lindenberg, Katja

    2017-02-01

    While it is widely accepted that information is encoded in neurons via action potentials or spikes, it is far less understood what specific features of spiking contain encoded information. Experimental evidence has suggested that the timing of the first spike may be an energy-efficient coding mechanism that contains more neural information than subsequent spikes. Therefore, the biophysical features of neurons that underlie response latency are of considerable interest. Here we examine the effects of channel noise on the first spike latency of a Hodgkin-Huxley neuron receiving random input from many other neurons. Because the principal feature of a Hodgkin-Huxley neuron is the stochastic opening and closing of channels, the fluctuations in the number of open channels lead to fluctuations in the membrane voltage and modify the timing of the first spike. Our results show that when a neuron has a larger number of channels, (i) the occurrence of the first spike is delayed and (ii) the variation in the first spike timing is greater. We also show that the mean, median, and interquartile range of first spike latency can be accurately predicted from a simple linear regression by knowing only the number of channels in the neuron and the rate at which presynaptic neurons fire, but the standard deviation (i.e., neuronal jitter) cannot be predicted using only this information. We then compare our results to another commonly used stochastic Hodgkin-Huxley model and show that the more commonly used model overstates the first spike latency but can predict the standard deviation of first spike latencies accurately. We end by suggesting a more suitable definition for the neuronal jitter based upon our simulations and comparison of the two models.

  9. Rival Visions: J.J. Rousseau and T.H. Huxley on the Nature (or Nurture) of Inequality and What It Means for Education

    ERIC Educational Resources Information Center

    Currie-Knight, Kevin

    2011-01-01

    Jean-Jacques Rousseau (1712-1778) and Thomas Huxley (1852-1895) had different, but substantial, effects on the history of education. Rousseau's educational theories supplied the intellectual foundation for pedagogical progressivism. Huxley's educational writings helped to enlarge the scope of the British curriculum to include such things as…

  10. EPA Void Letter for Suzuki

    EPA Pesticide Factsheets

    When a certificate is voided, EPA issues a void letter to the manufacturer.November 30, 2016, letter from Byron Bunker to Suzuki Motor America Inc., voiding certificate of conformity for highway motorcycle engine family CSKXC.652VR1.

  11. Solutions of the Hodgkin-Huxley equations modified for potassium accumulation in a periaxonal space.

    PubMed

    Adelman, W J; Fitzhugh, R

    1975-04-01

    Hodgkin and Huxley equations were modified to include the properties of an external diffusion barrier separated from the axolemma by a thin periaxonal space in which potassium ions accumulate as a function of membrane activity. Further modifications in the equations took into account new values for gK and new functions for alphan, betan, alphah, and betah derived from voltage clamp experiments on Loligo pealei giant axons. Equations were solved on a PDP-11 computer using the Gear predictor-corrector numerical method. In comparison with the original Hodgkin and Huxley equations, the modified equations for membrane potentials gave: 1) more accurate representations of the falling and undershoot phases of the membrane action potential, 2) more accurate representation of thresholds and latencies, 3) increases in the periaxonal space potassium ion concentration, Ks, of about 1 mM/impulse, 4) proper predictions of the time course and magnitude of either undershoot decline or periaxonal potassium ion accumulation during trains of membrane action potentials elicited by repetitivie short duration stimuli, and5) a somewhat more accurate representation of adaptation (finite train and nonrepetitive responses) during long duration constant current stimulation.

  12. A comparison of letter and digit processing in letter-by-letter reading.

    PubMed

    Ingles, Janet L; Eskes, Gail A

    2008-01-01

    The extent to which letter-by-letter reading results from a specific orthographic deficit, as compared with a nonspecific disturbance in basic visuoperceptual mechanisms, is unclear. The current study directly compared processing of letters and digits in a letter-by-letter reader, G.M., using a rapid serial visual presentation (RSVP) task and a speeded matching task. Comparisons were made to a group of six brain-damaged individuals without reading deficits. In the RSVP task, G.M. had increased difficulty reporting the target identities when they were letters, as compared with digits. Although this general pattern was also evident in the control group, the magnitude of the letter-digit accuracy difference was greater in G.M. Similarly, in the matching task, G.M. was slower to match letters than digits, relative to the control group, although his response times to both item types were increased. These data suggest that letter-by-letter reading, at least in this case, results from a visuoperceptual encoding deficit that particularly affects letters, but also extends to processing of digits to a lesser extent. Results are consistent with the notion that a left occipitotemporal area is specialized for letter processing with greater bilaterality in the visual processing of digits.

  13. Taxicab Correspondence Analysis.

    PubMed

    Choulakian, V

    2006-06-01

    Taxicab correspondence analysis is based on the taxicab singular value decomposition of a contingency table, and it shares some similar properties with correspondence analysis. It is more robust than the ordinary correspondence analysis, because it gives uniform weights to all the points. The visual map constructed by taxicab correspondence analysis has a larger sweep and clearer perspective than the map obtained by correspondence analysis. Two examples are provided.

  14. Allographic Agraphia for Single letters

    PubMed Central

    Menichelli, Alina; Machetta, Francesca; Zadini, Antonella; Semenza, Carlo

    2012-01-01

    The case is reported of a patient (PS) who, following acute encephalitis with residual occipito-temporal damage, showed a selective deficit in writing cursive letters in isolation, but no difficulty to write cursive-case words and non-words. Notably, he was able to recognize the same allographs he could not write and to produce both single letters and words in print. In addition to this selective single letter writing difficulty, the patient demonstrated an inability to correctly perform a series of imagery tasks for cursive letters. PS’s performance may indicate that single letter production requires explicit imagery. Explicit imagery may not be required, instead, when letters have to be produced in the context of a word: letter production in this case may rely on implicit retrieval of well learned scripts in a procedural way. PMID:22713390

  15. Which children benefit from letter names in learning letter sounds?

    PubMed

    Treiman, Rebecca; Pennington, Bruce F; Shriberg, Lawrence D; Boada, Richard

    2008-03-01

    Typical U.S. children use their knowledge of letters' names to help learn the letters' sounds. They perform better on letter sound tests with letters that have their sounds at the beginnings of their names, such as v, than with letters that have their sounds at the ends of their names, such as m, and letters that do not have their sounds in their names, such as h. We found this same pattern among children with speech sound disorders, children with language impairments as well as speech sound disorders, and children who later developed serious reading problems. Even children who scored at chance on rhyming and sound matching tasks performed better on the letter sound task with letters such as v than with letters such as m and h. Our results suggest that a wide range of children use the names of letters to help learn the sounds and that phonological awareness, as conventionally measured, is not required in order to do so.

  16. Teaching letter sounds to kindergarten English language learners using incremental rehearsal.

    PubMed

    Peterson, Meredith; Brandes, Dana; Kunkel, Amy; Wilson, Jennifer; Rahn, Naomi L; Egan, Andrea; McComas, Jennifer

    2014-02-01

    Proficiency in letter-sound correspondence is important for decoding connected text. This study examined the effects of an evidence-based intervention, incremental rehearsal (IR), on the letter-sound expression of three kindergarten English language learners (ELLs) performing below the district benchmark for letter-sound fluency. Participants were native speakers of Hmong, Spanish, and Polish. A multiple-baseline design across sets of unknown letter sounds was used to evaluate the effects of IR on letter-sound expression. Visual analysis of the data showed an increase in level and trend when IR was introduced in each phase. Percentage of all non-overlapping data (PAND) ranged from 95% to 100%. All participants exceeded expected growth and reached the spring district benchmark for letter-sound fluency. Results suggest that IR is a promising intervention for increasing letter-sound expression for ELLs who evidence delays in acquiring letter sounds.

  17. Human dynamics: Darwin and Einstein correspondence patterns.

    PubMed

    Oliveira, João Gama; Barabási, Albert-László

    2005-10-27

    In an era when letters were the main means of exchanging scientific ideas and results, Charles Darwin (1809-82) and Albert Einstein (1879-1955) were notably prolific correspondents. But did their patterns of communication differ from those associated with the instant-access e-mail of modern times? Here we show that, although the means have changed, the communication dynamics have not: Darwin's and Einstein's patterns of correspondence and today's electronic exchanges follow the same scaling laws. However, the response times of their surface-mail communication is described by a different scaling exponent from e-mail communication, providing evidence for a new class of phenomena in human dynamics.

  18. Recovery in a letter-by-letter reader: more efficiency at the expense of normal reading strategy.

    PubMed

    Ablinger, Irene; Huber, Walter; Schattka, Kerstin I; Radach, Ralph

    2013-01-01

    Although changes in reading performance of recovering letter-by-letter readers have been described in some detail, no prior research has provided an in-depth analysis of the underlying adaptive word processing strategies. Our work examined the reading performance of a letter-by-letter reader, FH, over a period of 15 months, using eye movement methodology to delineate the recovery process at two different time points (T1, T2). A central question is whether recovery is characterized either by moving back towards normal word processing or by refinement and possibly automatization of an existing pathological strategy that was developed in response to the impairment. More specifically, we hypothesized that letter-by-letter reading may be executed with at least four different strategies and our work sought to distinguish between these alternatives. During recovery significant improvements in reading performance were achieved. A shift of fixation positions from the far left to the extreme right of target words was combined with many small and very few longer regressive saccades. Apparently, 'letter-by-letter reading' took the form of local clustering, most likely corresponding to the formation of sublexical units of analysis. This pattern was more pronounced at T2, suggesting that improvements in reading efficiency may come at the expense of making it harder to eventually return to normal reading.

  19. Letter to an ethicist

    PubMed Central

    Silver, Malcolm; Crelinsten, Gordon

    1995-01-01

    Just as issues have arisen in court that cause the public to question whether the rights of criminals are taking precedence over the rights of victims, some physicians wonder if ethicists are placing the rights of some patients ahead of the rights of society and the common good. Pathologist Malcolm Silver raised this issue in a letter to the editor of CMAJ. With his permission, it was forwarded to Dr. Gordon Crelinsten, past chair of the ethics committee at the Royal Victoria Hospital in Montreal. PMID:7697584

  20. Letters to the Editor

    NASA Astrophysics Data System (ADS)

    1998-03-01

    All the Letters to the Editor in this issue are in the same PostScript or PDF file. Contents Comment on `Magnetic and electric field strengths of high voltage power lines and household appliances' José Luis Giordano Dept. de Ciencia y Tecnología de Materiales y Fluidos, CPSI, Universidad de Zaragoza, Spain Twins paradox S R Carson Norton College, Malton, North Yorkshire, UK On alternative ways of finding the ratio of specific heats of gases Tomas Ficker Physics Department, Technical University of Brno, Czech Republic

  1. Letters to the Editor

    NASA Astrophysics Data System (ADS)

    1998-01-01

    All the Letters to the Editor in this issue are in the same PostScript or PDF file. Contents Physics and history Arthur I Miller Department of Science & Technology Studies, University College London, Gower Street, London WC1E 6BT, UK Physics and history: a reply David Miller Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, UK Cathode rays, the electron and Thomson's discovery John Harris 33 Glentham Road, London SW13 9JD, UK Vectors: swallow them whole! David Wheeler Mahanakorn University of Technology, Bangkok, Thailand

  2. Taxicab Correspondence Analysis

    ERIC Educational Resources Information Center

    Choulakian, V.

    2006-01-01

    Taxicab correspondence analysis is based on the taxicab singular value decomposition of a contingency table, and it shares some similar properties with correspondence analysis. It is more robust than the ordinary correspondence analysis, because it gives uniform weights to all the points. The visual map constructed by taxicab correspondence…

  3. Task switching and response correspondence in the psychological refractory period paradigm

    NASA Technical Reports Server (NTRS)

    Lien, Mei-Ching; Schweickert, Richard; Proctor, Robert W.

    2003-01-01

    Three experiments examined the effects of task switching and response correspondence in a psychological refractory period paradigm. A letter task (vowel-consonant) and a digit task (odd-even) were combined to form 4 possible dual-task pairs in each trial: letter-letter, letter-digit, digit-digit, and digit-letter. Foreknowledge of task transition (repeat or switch) and task identity (letter or digit) was varied across experiments: no foreknowledge in Experiment 1, partial foreknowledge (task transition only) in Experiment 2, and full foreknowledge in Experiment 3. For all experiments, the switch cost for Task 2 was additive with stimulus onset asynchrony, and the response-correspondence effect for Task 2 was numerically smaller in the switch condition than in the repeat condition. These outcomes suggest that reconfiguration for Task 2 takes place after the central processing of Task 1 and that the crosstalk correspondence effect is due to response activation by way of stimulus-response associations.

  4. Enhancing the Hodgkin-Huxley Equations: Simulations Based on the First Publication in the Biophysical Journal.

    PubMed

    Moore, John W

    2015-10-06

    The experiments in the Cole and Moore article in the first issue of the Biophysical Journal provided the first independent experimental confirmation of the Hodgkin-Huxley (HH) equations. A log-log plot of the K current versus time showed that raising the HH variable n to the sixth power provided the best fit to the data. Subsequent simulations using n(6) and setting the resting potential at the in vivo value simplifies the HH equations by eliminating the leakage term. Our article also reported that the K current in response to a depolarizing step to ENa was delayed if the step was preceded by a hyperpolarization. While the interpretation of this phenomenon in the article was flawed, subsequent simulations show that the effect completely arises from the original HH equations.

  5. Bifurcation analysis of mode-locking structure in a Hodgkin-Huxley neuron under sinusoidal current

    NASA Astrophysics Data System (ADS)

    Lee, Sang-Gui; Kim, Seunghwan

    2006-04-01

    Nervous systems under periodic stimuli display rich dynamical states including mode-locking and chaotic responses, which have been a subject of intense studies in neurodynamics. The bifurcation structure of the Hodgkin-Huxley neuron under sinusoidal stimulus is studied in detail. The mechanisms of the firing onset and rich firing dynamics are studied with the help of the codimension-2 bifurcations, which play the role of the organizing center for myriads of saddle-node, period-doubling, and inverse-flip bifurcations forming the boundaries of the complex mode-locking structure. This study provides a useful insight into the organization of similar bifurcation structures in excitable systems such as neurons under periodic forcing.

  6. Studies of phase return map and symbolic dynamics in a periodically driven Hodgkin—Huxley neuron

    NASA Astrophysics Data System (ADS)

    Ding, Jiong; Zhang, Hong; Tong, Qin-Ye; Chen, Zhuo

    2014-02-01

    How neuronal spike trains encode external information is a hot topic in neurodynamics studies. In this paper, we investigate the dynamical states of the Hodgkin—Huxley neuron under periodic forcing. Depending on the parameters of the stimulus, the neuron exhibits periodic, quasiperiodic and chaotic spike trains. In order to analyze these spike trains quantitatively, we use the phase return map to describe the dynamical behavior on a one-dimensional (1D) map. According to the monotonicity or discontinuous point of the 1D map, the spike trains are transformed into symbolic sequences by implementing a coarse-grained algorithm — symbolic dynamics. Based on the ordering rules of symbolic dynamics, the parameters of the external stimulus can be measured in high resolution with finite length symbolic sequences. A reasonable explanation for why the nervous system can discriminate or cognize the small change of the external signals in a short time is also presented.

  7. Predicting the past: ancient eclipses and Airy, Newcomb, and Huxley on the authority of science.

    PubMed

    Stanley, Matthew

    2012-06-01

    Greek historical accounts of ancient eclipses were an important, if peculiar, focus of scientific attention in the nineteenth century. Victorian-era astronomers tried to correct the classical histories using scientific methods, then used those histories as data with which to calibrate their lunar theories, then rejected the histories as having any relevance at all. The specific dating of these eclipses--apparently a simple exercise in celestial mechanics--became bound up with tensions between scientific and humanistic approaches to the past as well as with wider social debates over the power and authority of science in general. The major figures discussed here, including G. B. Airy, Simon Newcomb, and T. H. Huxley, argued that the critical question was whether science could speak authoritatively about the past. To them, the ability of science to talk about the past indicated its power to talk about the future; it was also the fulcrum of fierce boundary disputes among science, history, and religion.

  8. Dynamic range in small-world networks of Hodgkin-Huxley neurons with chemical synapses

    NASA Astrophysics Data System (ADS)

    Batista, C. A. S.; Viana, R. L.; Lopes, S. R.; Batista, A. M.

    2014-09-01

    According to Stevens' law the relationship between stimulus and response is a power-law within an interval called the dynamic range. The dynamic range of sensory organs is found to be larger than that of a single neuron, suggesting that the network structure plays a key role in the behavior of both the scaling exponent and the dynamic range of neuron assemblies. In order to verify computationally the relationships between stimulus and response for spiking neurons, we investigate small-world networks of neurons described by the Hodgkin-Huxley equations connected by chemical synapses. We found that the dynamic range increases with the network size, suggesting that the enhancement of the dynamic range observed in sensory organs, with respect to single neurons, is an emergent property of complex network dynamics.

  9. Effect of Random Link Malfunctions to Synchronization of Hodgkin-Huxley Neurons in a Lattice Network

    NASA Astrophysics Data System (ADS)

    Pang, James Christopher S.; Bantang, Johnrob Y.; Monterola, Christopher P.

    2012-04-01

    We study the synchronization of Hodgkin-Huxley (HH) neurons connected in a directed lattice network under the influence of varying coupling strength (g) and random link malfunctions in the form of probabilistic deletion (probability q) and link direction flipping (p). We quantify the extent of synchronization of the neurons in the network by averaging the fraction of firing neurons that produce action potentials (exceeding a threshold potential of Vth) across the entire observation time. By extensively scanning over the values of g, synchronization of this network type can be enhanced by increasing g until it reaches a threshold value wherein synchronization will deteriorate abruptly due to suppression of neural firings. We also extensively probe the interplay of p and q and show that there are certain combinations for which the synchronization will improve, defying negative notions of how we perceive random malfunctions.

  10. Emergent Central Pattern Generator Behavior in Gap-Junction-Coupled Hodgkin-Huxley Style Neuron Model

    PubMed Central

    Memelli, Heraldo; Solomon, Irene C.

    2012-01-01

    Most models of central pattern generators (CPGs) involve two distinct nuclei mutually inhibiting one another via synapses. Here, we present a single-nucleus model of biologically realistic Hodgkin-Huxley neurons with random gap junction coupling. Despite no explicit division of neurons into two groups, we observe a spontaneous division of neurons into two distinct firing groups. In addition, we also demonstrate this phenomenon in a simplified version of the model, highlighting the importance of afterhyperpolarization currents (IAHP) to CPGs utilizing gap junction coupling. The properties of these CPGs also appear sensitive to gap junction conductance, probability of gap junction coupling between cells, topology of gap junction coupling, and, to a lesser extent, input current into our simulated nucleus. PMID:23365558

  11. Emergent central pattern generator behavior in gap-junction-coupled Hodgkin-Huxley style neuron model.

    PubMed

    Horn, Kyle G; Memelli, Heraldo; Solomon, Irene C

    2012-01-01

    Most models of central pattern generators (CPGs) involve two distinct nuclei mutually inhibiting one another via synapses. Here, we present a single-nucleus model of biologically realistic Hodgkin-Huxley neurons with random gap junction coupling. Despite no explicit division of neurons into two groups, we observe a spontaneous division of neurons into two distinct firing groups. In addition, we also demonstrate this phenomenon in a simplified version of the model, highlighting the importance of afterhyperpolarization currents (I(AHP)) to CPGs utilizing gap junction coupling. The properties of these CPGs also appear sensitive to gap junction conductance, probability of gap junction coupling between cells, topology of gap junction coupling, and, to a lesser extent, input current into our simulated nucleus.

  12. Control of bursting synchronization in networks of Hodgkin-Huxley-type neurons with chemical synapses

    NASA Astrophysics Data System (ADS)

    Batista, C. A. S.; Viana, R. L.; Ferrari, F. A. S.; Lopes, S. R.; Batista, A. M.; Coninck, J. C. P.

    2013-04-01

    Thermally sensitive neurons present bursting activity for certain temperature ranges, characterized by fast repetitive spiking of action potential followed by a short quiescent period. Synchronization of bursting activity is possible in networks of coupled neurons, and it is sometimes an undesirable feature. Control procedures can suppress totally or partially this collective behavior, with potential applications in deep-brain stimulation techniques. We investigate the control of bursting synchronization in small-world networks of Hodgkin-Huxley-type thermally sensitive neurons with chemical synapses through two different strategies. One is the application of an external time-periodic electrical signal and another consists of a time-delayed feedback signal. We consider the effectiveness of both strategies in terms of protocols of applications suitable to be applied by pacemakers.

  13. Autaptic activity-induced synchronization transitions in Newman-Watts network of Hodgkin-Huxley neurons.

    PubMed

    Wu, Yanan; Gong, Yubing; Wang, Qi

    2015-04-01

    In this paper, we numerically study the effect of autapse on the synchronization of Newman-Watts small-world Hodgkin-Huxley neuron network. It is found that the neurons exhibit synchronization transitions as autaptic self-feedback delay is varied, and the phenomenon becomes strongest when autaptic self-feedback strength is optimal. This phenomenon also changes with the change of coupling strength and network randomness and become strongest when they are optimal. There are similar synchronization transitions for electrical and chemical autapse, but the synchronization transitions for chemical autapse occur more frequently and are stronger than those for electrical synapse. The underlying mechanisms are briefly discussed in quality. These results show that autaptic activity plays a subtle role in the synchronization of the neuronal network. These findings may find potential implications of autapse for the information processing and transmission in neural systems.

  14. A novel approach to simulate Hodgkin-Huxley-like excitation with COMSOL Multiphysics.

    PubMed

    Martinek, Johannes; Stickler, Yvonne; Reichel, Martin; Mayr, Winfried; Rattay, Frank

    2008-08-01

    A proof of concept for the evaluation of external nerve and muscle fiber excitation with the finite element software COMSOL Multiphysics, formerly known as FEMLAB, is presented. This software allows the simultaneous solution of fiber excitation by 1D models of the Hodgkin-Huxley type which are embedded in a volume conductor where the electric field is mainly dominated by the electrode currents. This way the presented bidomain model includes the interaction between electrode currents and transmembrane currents during the excitation process. Especially for direct muscle fiber stimulation (cardiac muscle, denervated muscle) the effects from secondary currents from large populations of excited fibers seem to be significant. The method has many applications, for example, the relation between stimulus parameters and fiber recruitment can be analyzed.

  15. Mathematical description of a bursting pacemaker neuron by a modification of the Hodgkin-Huxley equations.

    PubMed Central

    Plant, R E; Kim, M

    1976-01-01

    Modifications based on experimental results reported in the literature are made to the Hodgkin-Huxley equations to describe the electrophysiological behavior of the Aplysia abdominal ganglion R15 cell. The system is then further modified to describe the effects with the application of the drug tetrodotoxin (TTX) to the cells' bathing medium. Methods of the qualitative theory of differential equations are used to determine the conditions necessary for such a system of equations to have an oscillatory solution. A model satisfying these conditions is shown to preduct many experimental observations of R15 cell behavior. Numerical solutions are obtained for differential equations satisfying the conditions of the model. These solutions are shown to have a form similar to that of the bursting which is characteristic of this cell, and to preduct many results of experiments conducted on this cell. The physiological implications of the model are discussed. Images FIGURE 6 PMID:1252578

  16. Rhythmic Oscillations of Excitatory Bursting Hodkin-Huxley Neuronal Network with Synaptic Learning

    PubMed Central

    Shi, Qi; Han, Fang; Wang, Zhijie; Li, Caiyun

    2016-01-01

    Rhythmic oscillations of neuronal network are actually kind of synchronous behaviors, which play an important role in neural systems. In this paper, the properties of excitement degree and oscillation frequency of excitatory bursting Hodkin-Huxley neuronal network which incorporates a synaptic learning rule are studied. The effects of coupling strength, synaptic learning rate, and other parameters of chemical synapses, such as synaptic delay and decay time constant, are explored, respectively. It is found that the increase of the coupling strength can weaken the extent of excitement, whereas increasing the synaptic learning rate makes the network more excited in a certain range; along with the increasing of the delay time and the decay time constant, the excitement degree increases at the beginning, then decreases, and keeps stable. It is also found that, along with the increase of the synaptic learning rate, the coupling strength, the delay time, and the decay time constant, the oscillation frequency of the network decreases monotonically. PMID:27073393

  17. Homoclinic bifurcation in a Hodgkin-Huxley model of thermally sensitive neurons

    SciTech Connect

    Feudel, Ulrike; Neiman, Alexander; Pei, Xing; Wojtenek, Winfried; Braun, Hans; Huber, Martin; Moss, Frank

    2000-03-01

    We study global bifurcations of the chaotic attractor in a modified Hodgkin-Huxley model of thermally sensitive neurons. The control parameter for this model is the temperature. The chaotic behavior is realized over a wide range of temperatures and is visualized using interspike intervals. We observe an abrupt increase of the interspike intervals in a certain temperature region. We identify this as a homoclinic bifurcation of a saddle-focus fixed point which is embedded in the chaotic attractors. The transition is accompanied by intermittency, which obeys a universal scaling law for the average length of trajectory segments exhibiting only short interspike intervals with the distance from the onset of intermittency. We also present experimental results of interspike interval measurements taken from the crayfish caudal photoreceptor, which qualitatively demonstrate the same bifurcation structure. (c) 2000 American Institute of Physics.

  18. Breaking Object Correspondence Across Saccadic Eye Movements Deteriorates Object Recognition.

    PubMed

    Poth, Christian H; Herwig, Arvid; Schneider, Werner X

    2015-01-01

    Visual perception is based on information processing during periods of eye fixations that are interrupted by fast saccadic eye movements. The ability to sample and relate information on task-relevant objects across fixations implies that correspondence between presaccadic and postsaccadic objects is established. Postsaccadic object information usually updates and overwrites information on the corresponding presaccadic object. The presaccadic object representation is then lost. In contrast, the presaccadic object is conserved when object correspondence is broken. This helps transsaccadic memory but it may impose attentional costs on object recognition. Therefore, we investigated how breaking object correspondence across the saccade affects postsaccadic object recognition. In Experiment 1, object correspondence was broken by a brief postsaccadic blank screen. Observers made a saccade to a peripheral object which was displaced during the saccade. This object reappeared either immediately after the saccade or after the blank screen. Within the postsaccadic object, a letter was briefly presented (terminated by a mask). Observers reported displacement direction and letter identity in different blocks. Breaking object correspondence by blanking improved displacement identification but deteriorated postsaccadic letter recognition. In Experiment 2, object correspondence was broken by changing the object's contrast-polarity. There were no object displacements and observers only reported letter identity. Again, breaking object correspondence deteriorated postsaccadic letter recognition. These findings identify transsaccadic object correspondence as a key determinant of object recognition across the saccade. This is in line with the recent hypothesis that breaking object correspondence results in separate representations of presaccadic and postsaccadic objects which then compete for limited attentional processing resources (Schneider, 2013). Postsaccadic object recognition is

  19. Half a Century of Physical Review Letters

    ScienceCinema

    Garisto, Robert

    2016-07-12

    Fifty years ago, Sam Goudsmit started an experiment: the journal Physical Review Letters.  Since 1958, the experiment has thrived. PRL has gone through many changes, published many important papers, and become a leader in international scientific publication.  I will trace the rise of PRL from its early 20th century roots as "Letters to the Editor," through changes in editorial process and advents of new technology. Along the way I'll show what has gone on behind the scenes, and give a glimpse of our plans for the future.  I'll also give some advice to would-be authors and referees, illustrated with interesting correspondence we've received.

  20. Michael Maier--nine newly discovered letters.

    PubMed

    Lenke, Nils; Roudet, Nicolas; Tilton, Hereward

    2014-02-01

    The authors provide a transcription, translation, and evaluation of nine newly discovered letters from the alchemist Michael Maier (1568-1622) to Gebhardt Johann von Alvensleben (1576-1631), a noble landholder in the vicinity of Magdeburg. Stemming from the final year of his life, this correspondence casts new light on Maier's biography, detailing his efforts to secure patronage amid the financial crisis of the early Thirty Years' War. While his ill-fated quest to perfect potable gold continued to form the central focus of his patronage suits, Maier also offered his services in several arts that he had condemned in his printed works, namely astrology and "supernatural" magic. Remarks concerning his previously unknown acquaintance with Heinrich Khunrath call for a re-evaluation of Maier's negotiation of the discursive boundaries between Lutheran orthodoxy and Paracelsianism. The letters also reveal Maier's substantial contribution to a work previously ascribed solely to the English alchemist Francis Anthony.

  1. What Can Reduce Letter Migrations in Letter Position Dyslexia?

    ERIC Educational Resources Information Center

    Friedmann, Naama; Rahamim, Einav

    2014-01-01

    Letter position dyslexia (LPD) is a peripheral dyslexia that causes errors of letter position within words, such as reading "cloud" as "could." In this study, we assessed the effect of various display manipulations and reading methods on the reading of 10 Hebrew readers with developmental LPD. These manipulations included…

  2. The Visuo-Haptic and Haptic Exploration of Letters Increases the Kindergarten-Children's Understanding of the Alphabetic Principle

    ERIC Educational Resources Information Center

    Bara, Florence; Gentaz, Edouard; Cole, Pascale; Sprenger-Charolles, Liliane

    2004-01-01

    This study examined the effect of incorporating a visuo-haptic and haptic (tactual-kinaesthetic) exploration of letters in a training designed to develop phonemic awareness, knowledge of letters and letter/sound correspondences, on 5-year-old children's understanding and use of the alphabetic principle. Three interventions, which differed in the…

  3. The rhetoric of patient voice: reported talk with patients in referral and consultation letters.

    PubMed

    Spafford, Marlee M; Schryer, Catherine F; Lingard, Lorelei

    2008-01-01

    Referral and consultation letters are written to enable the exchange of patient information and facilitate the trajectory of patients through the healthcare system. Yet, these letters, written about yet apart from patients, also sustain and constrain professional relationships and influence attitudes towards patients. We analysed 35 optometry referral letters and 35 corresponding ophthalmology consultation letters for reported 'patient voice' coded as 'experience' or 'agenda' and we interviewed 15 letter writers (eight optometry students, six optometrists, and one community ophthalmologist). There were 80 instances of reported 'patient voice' in 35 letters. The majority (68%) of the instances occurred in referral letters, likely due to differences in both 'letter function' and 'professional stance.' Reported 'patient voice' occurred predominantly as 'experience' (81%) rather than 'agenda' instances. Letters writers focused on their readers' needs, thus a biomedical voice dominated the letters and instances of reported 'patient voice' were recontextualized for the professional audience. While reporting 'patient voice' was not the norm in these letters, its inclusion appeared to accomplish specific work: to persuade reader action, to question patient credibility, and to highlight patient agency. These letter strategies reflect professional attitudes about patients and their care.

  4. Demonstrating the Correspondence Bias

    ERIC Educational Resources Information Center

    Howell, Jennifer L.; Shepperd, James A.

    2011-01-01

    Among the best-known and most robust biases in person perception is the correspondence bias--the tendency for people to make dispositional, rather than situational, attributions for an actor's behavior. The correspondence bias appears in virtually every social psychology textbook and in many introductory psychology textbooks, yet the authors'…

  5. Letters in Biographies and Novels.

    ERIC Educational Resources Information Center

    Paterra, Elizabeth

    1997-01-01

    This is an annotated bibliography of biographies, historical fiction, contemporary stories, and discussion questions related to letter writing. A sidebar suggests an activity that involves reading a book about Ludwig van Beethoven, listening to Beethoven's music, and discussing letters in the story. (DGM)

  6. Complex Correspondence Principle

    SciTech Connect

    Bender, Carl M.; Meisinger, Peter N.; Hook, Daniel W.; Wang Qinghai

    2010-02-12

    Quantum mechanics and classical mechanics are distinctly different theories, but the correspondence principle states that quantum particles behave classically in the limit of high quantum number. In recent years much research has been done on extending both quantum and classical mechanics into the complex domain. These complex extensions continue to exhibit a correspondence, and this correspondence becomes more pronounced in the complex domain. The association between complex quantum mechanics and complex classical mechanics is subtle and demonstrating this relationship requires the use of asymptotics beyond all orders.

  7. The standard Hodgkin-Huxley model and squid axons in reduced external Ca++ fail to accommodate to slowly rising currents.

    PubMed Central

    Jakobsson, E; Guttman, R

    1980-01-01

    Accommodation may be defined as an increase in the threshold of an excitable membrane when the membrane is subjected to a sustained subthreshold depolarizing stimulus. Some excitable membranes show accommodation in response to currents which rise linearly at a very slow rate. In this report we point out a theoretical and an experimental counterexample, i.e., a nerve model and an axon which do not accommodate. The nerve model is the standard Hodgkin-Huxley axon, which Hodgkin and Huxley expected not to be excited by a very slowly rising current. This expectation is often quoted as fact, in spite of contrary calculations which we confirm. We have found that squid axons in seawater with reduced divalent cation concentration also do not accommodate to slowly rising currents. Images FIGURE 2 PMID:7260290

  8. Two New Letters by Denning

    NASA Astrophysics Data System (ADS)

    Beech, Martin

    2010-06-01

    Two letters written by W. F. Denning to R. P. Greg in March and April of 1879 that had been tucked into the folds of an 1876 edition of the British Association for the Advancement of Science Reports were recently found at the Carnegie Institution in Washington D.C. The letters are wonderfully preserved, and offer us a snap-shot of the work being performed by a young Denning at the time when his influence in the field of meteor studies was in its ascendency. The contents of these two letters is analyzed and placed within context to Denning's other publications and private life.

  9. Multiclass Continuous Correspondence Learning

    NASA Technical Reports Server (NTRS)

    Bue, Brian D,; Thompson, David R.

    2011-01-01

    We extend the Structural Correspondence Learning (SCL) domain adaptation algorithm of Blitzer er al. to the realm of continuous signals. Given a set of labeled examples belonging to a 'source' domain, we select a set of unlabeled examples in a related 'target' domain that play similar roles in both domains. Using these 'pivot samples, we map both domains into a common feature space, allowing us to adapt a classifier trained on source examples to classify target examples. We show that when between-class distances are relatively preserved across domains, we can automatically select target pivots to bring the domains into correspondence.

  10. The Complaint Letter and Response.

    ERIC Educational Resources Information Center

    Shukla, P. K.

    1998-01-01

    Describes an assignment in which students write a letter of complaint, and discusses how this assignment aids students in seeing the importance of effective written communication to their daily lives. (SR)

  11. Neural Energy Supply-Consumption Properties Based on Hodgkin-Huxley Model

    PubMed Central

    2017-01-01

    Electrical activity is the foundation of the neural system. Coding theories that describe neural electrical activity by the roles of action potential timing or frequency have been thoroughly studied. However, an alternative method to study coding questions is the energy method, which is more global and economical. In this study, we clearly defined and calculated neural energy supply and consumption based on the Hodgkin-Huxley model, during firing action potentials and subthreshold activities using ion-counting and power-integral model. Furthermore, we analyzed energy properties of each ion channel and found that, under the two circumstances, power synchronization of ion channels and energy utilization ratio have significant differences. This is particularly true of the energy utilization ratio, which can rise to above 100% during subthreshold activity, revealing an overdraft property of energy use. These findings demonstrate the distinct status of the energy properties during neuronal firings and subthreshold activities. Meanwhile, after introducing a synapse energy model, this research can be generalized to energy calculation of a neural network. This is potentially important for understanding the relationship between dynamical network activities and cognitive behaviors. PMID:28316842

  12. FPGA implementation of a biological neural network based on the Hodgkin-Huxley neuron model

    PubMed Central

    Yaghini Bonabi, Safa; Asgharian, Hassan; Safari, Saeed; Nili Ahmadabadi, Majid

    2014-01-01

    A set of techniques for efficient implementation of Hodgkin-Huxley-based (H-H) model of a neural network on FPGA (Field Programmable Gate Array) is presented. The central implementation challenge is H-H model complexity that puts limits on the network size and on the execution speed. However, basics of the original model cannot be compromised when effect of synaptic specifications on the network behavior is the subject of study. To solve the problem, we used computational techniques such as CORDIC (Coordinate Rotation Digital Computer) algorithm and step-by-step integration in the implementation of arithmetic circuits. In addition, we employed different techniques such as sharing resources to preserve the details of model as well as increasing the network size in addition to keeping the network execution speed close to real time while having high precision. Implementation of a two mini-columns network with 120/30 excitatory/inhibitory neurons is provided to investigate the characteristic of our method in practice. The implementation techniques provide an opportunity to construct large FPGA-based network models to investigate the effect of different neurophysiological mechanisms, like voltage-gated channels and synaptic activities, on the behavior of a neural network in an appropriate execution time. Additional to inherent properties of FPGA, like parallelism and re-configurability, our approach makes the FPGA-based system a proper candidate for study on neural control of cognitive robots and systems as well. PMID:25484854

  13. Quantification of degeneracy in Hodgkin-Huxley neurons on Newman-Watts small world network.

    PubMed

    Man, Menghua; Zhang, Ya; Ma, Guilei; Friston, Karl; Liu, Shanghe

    2016-08-07

    Degeneracy is a fundamental source of biological robustness, complexity and evolvability in many biological systems. However, degeneracy is often confused with redundancy. Furthermore, the quantification of degeneracy has not been addressed for realistic neuronal networks. The objective of this paper is to characterize degeneracy in neuronal network models via quantitative mathematic measures. Firstly, we establish Hodgkin-Huxley neuronal networks with Newman-Watts small world network architectures. Secondly, in order to calculate the degeneracy, redundancy and complexity in the ensuing networks, we use information entropy to quantify the information a neuronal response carries about the stimulus - and mutual information to measure the contribution of each subset of the neuronal network. Finally, we analyze the interdependency of degeneracy, redundancy and complexity - and how these three measures depend upon network architectures. Our results suggest that degeneracy can be applied to any neuronal network as a formal measure, and degeneracy is distinct from redundancy. Qualitatively degeneracy and complexity are more highly correlated over different network architectures, in comparison to redundancy. Quantitatively, the relationship between both degeneracy and redundancy depends on network coupling strength: both degeneracy and redundancy increase with complexity for small coupling strengths; however, as coupling strength increases, redundancy decreases with complexity (in contrast to degeneracy, which is relatively invariant). These results suggest that the degeneracy is a general topologic characteristic of neuronal networks, which could be applied quantitatively in neuroscience and connectomics.

  14. FPGA implementation of a biological neural network based on the Hodgkin-Huxley neuron model.

    PubMed

    Yaghini Bonabi, Safa; Asgharian, Hassan; Safari, Saeed; Nili Ahmadabadi, Majid

    2014-01-01

    A set of techniques for efficient implementation of Hodgkin-Huxley-based (H-H) model of a neural network on FPGA (Field Programmable Gate Array) is presented. The central implementation challenge is H-H model complexity that puts limits on the network size and on the execution speed. However, basics of the original model cannot be compromised when effect of synaptic specifications on the network behavior is the subject of study. To solve the problem, we used computational techniques such as CORDIC (Coordinate Rotation Digital Computer) algorithm and step-by-step integration in the implementation of arithmetic circuits. In addition, we employed different techniques such as sharing resources to preserve the details of model as well as increasing the network size in addition to keeping the network execution speed close to real time while having high precision. Implementation of a two mini-columns network with 120/30 excitatory/inhibitory neurons is provided to investigate the characteristic of our method in practice. The implementation techniques provide an opportunity to construct large FPGA-based network models to investigate the effect of different neurophysiological mechanisms, like voltage-gated channels and synaptic activities, on the behavior of a neural network in an appropriate execution time. Additional to inherent properties of FPGA, like parallelism and re-configurability, our approach makes the FPGA-based system a proper candidate for study on neural control of cognitive robots and systems as well.

  15. Theoretical Analysis of Transcranial Magneto-Acoustical Stimulation with Hodgkin-Huxley Neuron Model

    PubMed Central

    Yuan, Yi; Chen, Yudong; Li, Xiaoli

    2016-01-01

    Transcranial magneto-acoustical stimulation (TMAS) is a novel stimulation technology in which an ultrasonic wave within a magnetostatic field generates an electric current in an area of interest in the brain to modulate neuronal activities. As a key part of the neural network, neurons transmit information in the nervous system. However, the effect of TMAS on the neuronal firing pattern remains unknown. To address this problem, we investigated the stimulatory mechanism of TMAS on neurons, by using a Hodgkin-Huxley neuron model. The simulation results indicated that the magnetostatic field intensity and ultrasonic power affect the amplitude and interspike interval of neuronal action potential under a continuous wave ultrasound. The simulation results also showed that the ultrasonic power, duty cycle and repetition frequency can alter the firing pattern of neural action potential under pulsed wave ultrasound. This study may help to reveal and explain the biological mechanism of TMAS and to provide a theoretical basis for TMAS in the treatment or rehabilitation of neuropsychiatric disorders. PMID:27148032

  16. Chimera states in a Hodgkin-Huxley model of thermally sensitive neurons

    NASA Astrophysics Data System (ADS)

    Glaze, Tera A.; Lewis, Scott; Bahar, Sonya

    2016-08-01

    Chimera states occur when identically coupled groups of nonlinear oscillators exhibit radically different dynamics, with one group exhibiting synchronized oscillations and the other desynchronized behavior. This dynamical phenomenon has recently been studied in computational models and demonstrated experimentally in mechanical, optical, and chemical systems. The theoretical basis of these states is currently under active investigation. Chimera behavior is of particular relevance in the context of neural synchronization, given the phenomenon of unihemispheric sleep and the recent observation of asymmetric sleep in human patients with sleep apnea. The similarity of neural chimera states to neural "bump" states, which have been suggested as a model for working memory and visual orientation tuning in the cortex, adds to their interest as objects of study. Chimera states have been demonstrated in the FitzHugh-Nagumo model of excitable cells and in the Hindmarsh-Rose neural model. Here, we demonstrate chimera states and chimera-like behaviors in a Hodgkin-Huxley-type model of thermally sensitive neurons both in a system with Abrams-Strogatz (mean field) coupling and in a system with Kuramoto (distance-dependent) coupling. We map the regions of parameter space for which chimera behavior occurs in each of the two coupling schemes.

  17. Dynamical response of the Hodgkin-Huxley model in the high-input regime

    NASA Astrophysics Data System (ADS)

    Luccioli, Stefano; Kreuz, Thomas; Torcini, Alessandro

    2006-04-01

    The response of the Hodgkin-Huxley neuronal model subjected to stochastic uncorrelated spike trains originating from a large number of inhibitory and excitatory post-synaptic potentials is analyzed in detail. The model is examined in its three fundamental dynamical regimes: silence, bistability, and repetitive firing. Its response is characterized in terms of statistical indicators (interspike-interval distributions and their first moments) as well as of dynamical indicators (autocorrelation functions and conditional entropies). In the silent regime, the coexistence of two different coherence resonances is revealed: one occurs at quite low noise and is related to the stimulation of subthreshold oscillations around the rest state; the second one (at intermediate noise variance) is associated with the regularization of the sequence of spikes emitted by the neuron. Bistability in the low noise limit can be interpreted in terms of jumping processes across barriers activated by stochastic fluctuations. In the repetitive firing regime a maximization of incoherence is observed at finite noise variance. Finally, the mechanisms responsible for the different features appearing in the interspike-interval distributions (like multimodality and exponential tails) are clearly identified in the various regimes.

  18. Neural Energy Supply-Consumption Properties Based on Hodgkin-Huxley Model.

    PubMed

    Wang, Yihong; Wang, Rubin; Xu, Xuying

    2017-01-01

    Electrical activity is the foundation of the neural system. Coding theories that describe neural electrical activity by the roles of action potential timing or frequency have been thoroughly studied. However, an alternative method to study coding questions is the energy method, which is more global and economical. In this study, we clearly defined and calculated neural energy supply and consumption based on the Hodgkin-Huxley model, during firing action potentials and subthreshold activities using ion-counting and power-integral model. Furthermore, we analyzed energy properties of each ion channel and found that, under the two circumstances, power synchronization of ion channels and energy utilization ratio have significant differences. This is particularly true of the energy utilization ratio, which can rise to above 100% during subthreshold activity, revealing an overdraft property of energy use. These findings demonstrate the distinct status of the energy properties during neuronal firings and subthreshold activities. Meanwhile, after introducing a synapse energy model, this research can be generalized to energy calculation of a neural network. This is potentially important for understanding the relationship between dynamical network activities and cognitive behaviors.

  19. Chimera states in a Hodgkin-Huxley model of thermally sensitive neurons.

    PubMed

    Glaze, Tera A; Lewis, Scott; Bahar, Sonya

    2016-08-01

    Chimera states occur when identically coupled groups of nonlinear oscillators exhibit radically different dynamics, with one group exhibiting synchronized oscillations and the other desynchronized behavior. This dynamical phenomenon has recently been studied in computational models and demonstrated experimentally in mechanical, optical, and chemical systems. The theoretical basis of these states is currently under active investigation. Chimera behavior is of particular relevance in the context of neural synchronization, given the phenomenon of unihemispheric sleep and the recent observation of asymmetric sleep in human patients with sleep apnea. The similarity of neural chimera states to neural "bump" states, which have been suggested as a model for working memory and visual orientation tuning in the cortex, adds to their interest as objects of study. Chimera states have been demonstrated in the FitzHugh-Nagumo model of excitable cells and in the Hindmarsh-Rose neural model. Here, we demonstrate chimera states and chimera-like behaviors in a Hodgkin-Huxley-type model of thermally sensitive neurons both in a system with Abrams-Strogatz (mean field) coupling and in a system with Kuramoto (distance-dependent) coupling. We map the regions of parameter space for which chimera behavior occurs in each of the two coupling schemes.

  20. A study of quantum mechanical probabilities in the classical Hodgkin-Huxley model.

    PubMed

    Moradi, N; Scholkmann, F; Salari, V

    2015-03-01

    The Hodgkin-Huxley (HH) model is a powerful model to explain different aspects of spike generation in excitable cells. However, the HH model was proposed in 1952 when the real structure of the ion channel was unknown. It is now common knowledge that in many ion-channel proteins the flow of ions through the pore is governed by a gate, comprising a so-called "selectivity filter" inside the ion channel, which can be controlled by electrical interactions. The selectivity filter (SF) is believed to be responsible for the selection and fast conduction of particular ions across the membrane of an excitable cell. Other (generally larger) parts of the molecule such as the pore-domain gate control the access of ions to the channel protein. In fact, two types of gates are considered here for ion channels: the "external gate", which is the voltage sensitive gate, and the "internal gate" which is the selectivity filter gate (SFG). Some quantum effects are expected in the SFG due to its small dimensions, which may play an important role in the operation of an ion channel. Here, we examine parameters in a generalized model of HH to see whether any parameter affects the spike generation. Our results indicate that the previously suggested semi-quantum-classical equation proposed by Bernroider and Summhammer (BS) agrees strongly with the HH equation under different conditions and may even provide a better explanation in some cases. We conclude that the BS model can refine the classical HH model substantially.

  1. The Correspondence Principle Revisited.

    ERIC Educational Resources Information Center

    Liboff, Richard L.

    1984-01-01

    Addresses the question of frequency correspondence in the domain of large quantum numbers, with reference to periodic systems. Provides two simple counterexamples (a particle in a cubical box and a rigid rotator) to show that the classical result is not always recovered in the limit of large quantum numbers. (JM)

  2. 19 CFR Policy Statement to Part 145 - Examination of Sealed Letter Class Mail

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... contained in any letter class mail unless there has been obtained in advance either a search warrant or... territory of the United States, unless a search warrant or written authorization of the sender or addressee... letter class mail which appears to contain only correspondence unless a search warrant or...

  3. 19 CFR Policy Statement to Part 145 - Examination of Sealed Letter Class Mail

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... contained in any letter class mail unless there has been obtained in advance either a search warrant or... territory of the United States, unless a search warrant or written authorization of the sender or addressee... letter class mail which appears to contain only correspondence unless a search warrant or...

  4. The Syllabic Bridge: The First Step in Learning Spelling-to-Sound Correspondences

    ERIC Educational Resources Information Center

    Doignon-Camus, Nadege; Zaga, Daniel

    2014-01-01

    It is widely agreed that learning to read starts with the establishment of letter-to-phoneme correspondences. However, it is also widely agreed that prereaders do not have access to phoneme units. Here we show that the building of associations between letters and syllables, which we call the "syllabic bridge", might be a faster and more…

  5. 22 CFR 9b.3 - Press correspondents employed by foreign media organizations.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ..., DC 20520 a letter from his or her organization stating: (1) That the applicant is a bona fide, full-time media correspondent based permanently and residing in the Washington, DC, metropolitan area: (2... regular attendance at the daily press briefings. (b) A letter from the Washington, DC Embassy of...

  6. Color associations for days and letters across different languages

    PubMed Central

    Rouw, Romke; Case, Laura; Gosavi, Radhika; Ramachandran, Vilayanur

    2014-01-01

    While colors are commonplace in everyday metaphors, relatively little is known about implicit color associations to linguistic or semantic concepts in a general population. In this study, we test color associations for ordered linguistic concepts (letters and days). The culture and language specificity of these effects was examined in a large group (457) of Dutch-speaking participants, 92 English-speaking participants, and 49 Hindi-speaking participants. Non-random distributions of color choices were revealed; consistencies were found across the three language groups in color preferences for both days and letters. Interestingly, while the Hindi-speaking participants were presented with letter stimuli matched on phonology, their pattern of letter-to-color preferences still showed similarities with Dutch- and English-speaking participants. Furthermore, we found that that the color preferences corresponded between participants indicating to have conscious color experiences with letters or days (putative synesthetes) and participants who do not (non-synesthetes). We also explored possible mechanisms underlying the color preferences. There were a few specific associations, including red for “A,” red for “Monday,” and white for “Sunday.” We also explored more general mechanisms, such as overall color preferences as shown by Simner et al. (2005). While certainly not all variation can be explained or predicted, the results show that regularities are present in color-to-letter or color-to-day preferences in both putative synesthetes and non-synesthetes across languages. Both letter-to-color and day-to-color preferences were influenced by multiple factors. The findings support a notion of abstract concepts (such as days and letters) that are not represented in isolation, but are connected to perceptual representational systems. Interestingly, at least some of these connections to color representations are shared across different language/cultural groups. PMID

  7. A correspondence principle

    NASA Astrophysics Data System (ADS)

    Hughes, Barry D.; Ninham, Barry W.

    2016-02-01

    A single mathematical theme underpins disparate physical phenomena in classical, quantum and statistical mechanical contexts. This mathematical "correspondence principle", a kind of wave-particle duality with glorious realizations in classical and modern mathematical analysis, embodies fundamental geometrical and physical order, and yet in some sense sits on the edge of chaos. Illustrative cases discussed are drawn from classical and anomalous diffusion, quantum mechanics of single particles and ideal gases, quasicrystals and Casimir forces.

  8. Letter Writing: A Tool for Counselor Educators

    ERIC Educational Resources Information Center

    Hoffman, Rachel M.

    2008-01-01

    Letter writing is an integral component of narrative therapy practice. In addition to the benefits of letter writing in counseling practice, letter writing may hold interesting possibilities for use in counselor education. This article provides a brief review of the benefits of letter writing in counseling practice and discusses the potential use…

  9. Embedded Picture Mnemonics to Learn Letters

    ERIC Educational Resources Information Center

    Shmidman, Adina; Ehri, Linnea

    2010-01-01

    Can embedded mnemonics ease the task of learning a foreign alphabet? English-speaking preschoolers (N = 36, M = 5;2 years) were taught 10 Hebrew letter-sound relations. Experimental letters were learned with mnemonics that embedded letter shapes in drawings of objects whose shapes resembled the letters and whose English names began with the…

  10. Essay: Physical Review Letters; Sam Goudsmit's Vision.

    PubMed

    Adair, Robert K

    2008-01-18

    Sam Goudsmit implemented his vision of converting the Letters section of Physical Review into a distinct journal fifty years ago. Physical Review Letters was designed to publish "only papers that really deserve rapid communication." The new journal became so successful with physicists throughout the world that Physical Review Letters now publishes 3500 Letters per year.

  11. Business Letter Writing: English, French, and Japanese.

    ERIC Educational Resources Information Center

    Jenkins, Susan; Hinds, John

    1987-01-01

    Examination of business letters in English, French, and Japanese, focusing on prescriptive accounts in the respective languages, found that, despite amazingly similar surface characteristics, American business letters were reader-oriented, French business letters were writer-oriented, and Japanese business letters were oriented to the space…

  12. A Common Left Occipito-Temporal Dysfunction in Developmental Dyslexia and Acquired Letter-By-Letter Reading?

    PubMed Central

    Richlan, Fabio; Sturm, Denise; Schurz, Matthias; Kronbichler, Martin; Ladurner, Gunther; Wimmer, Heinz

    2010-01-01

    Background We used fMRI to examine functional brain abnormalities of German-speaking dyslexics who suffer from slow effortful reading but not from a reading accuracy problem. Similar to acquired cases of letter-by-letter reading, the developmental cases exhibited an abnormal strong effect of length (i.e., number of letters) on response time for words and pseudowords. Results Corresponding to lesions of left occipito-temporal (OT) regions in acquired cases, we found a dysfunction of this region in our developmental cases who failed to exhibit responsiveness of left OT regions to the length of words and pseudowords. This abnormality in the left OT cortex was accompanied by absent responsiveness to increased sublexical reading demands in phonological inferior frontal gyrus (IFG) regions. Interestingly, there was no abnormality in the left superior temporal cortex which—corresponding to the onological deficit explanation—is considered to be the prime locus of the reading difficulties of developmental dyslexia cases. Conclusions The present functional imaging results suggest that developmental dyslexia similar to acquired letter-by-letter reading is due to a primary dysfunction of left OT regions. PMID:20711448

  13. Correspondence: Searching sequence space

    SciTech Connect

    Youvan, D.C.

    1995-08-01

    This correspondence debates the efficiency and application of genetic algorithms (GAs) to search protein sequence space. The important experimental point is that such sparse searches utilize physically realistic syntheses. In this regard, all GA-based technologies are very similar; they {open_quotes}learn{close_quotes} from their initial sparse search and then generate interesting new proteins within a few iterations. Which GA-based technology is best? That probably depends on the protein and the specific engineering goal. Given the fact that the field of combinatorial chemistry is still in its infancy, it is probably wise to consider all of the proven mutagenesis methods. 19 refs.

  14. Effects of Letter-Identification Training on Letter Naming in Prereading Children

    ERIC Educational Resources Information Center

    Hayashi, Yusuke; Schmidt, Anna C.; Saunders, Kathryn J.

    2013-01-01

    Three prereading children who named 0 to 3 of 20 targeted letters were taught to select the 20 printed letters when they heard spoken letter names. For all participants, letter-identification training resulted in naming for the majority of letters.

  15. Stochastic differential equation models for ion channel noise in Hodgkin-Huxley neurons.

    PubMed

    Goldwyn, Joshua H; Imennov, Nikita S; Famulare, Michael; Shea-Brown, Eric

    2011-04-01

    The random transitions of ion channels between conducting and nonconducting states generate a source of internal fluctuations in a neuron, known as channel noise. The standard method for modeling the states of ion channels nonlinearly couples continuous-time Markov chains to a differential equation for voltage. Beginning with the work of R. F. Fox and Y.-N. Lu [Phys. Rev. E 49, 3421 (1994)], there have been attempts to generate simpler models that use stochastic differential equation (SDEs) to approximate the stochastic spiking activity produced by Markov chain models. Recent numerical investigations, however, have raised doubts that SDE models can capture the stochastic dynamics of Markov chain models.We analyze three SDE models that have been proposed as approximations to the Markov chain model: one that describes the states of the ion channels and two that describe the states of the ion channel subunits. We show that the former channel-based approach can capture the distribution of channel noise and its effects on spiking in a Hodgkin-Huxley neuron model to a degree not previously demonstrated, but the latter two subunit-based approaches cannot. Our analysis provides intuitive and mathematical explanations for why this is the case. The temporal correlation in the channel noise is determined by the combinatorics of bundling subunits into channels, but the subunit-based approaches do not correctly account for this structure. Our study confirms and elucidates the findings of previous numerical investigations of subunit-based SDE models. Moreover, it presents evidence that Markov chain models of the nonlinear, stochastic dynamics of neural membranes can be accurately approximated by SDEs. This finding opens a door to future modeling work using SDE techniques to further illuminate the effects of ion channel fluctuations on electrically active cells.

  16. Power-Law Dynamics of Membrane Conductances Increase Spiking Diversity in a Hodgkin-Huxley Model

    PubMed Central

    Teka, Wondimu; Stockton, David; Santamaria, Fidel

    2016-01-01

    We studied the effects of non-Markovian power-law voltage dependent conductances on the generation of action potentials and spiking patterns in a Hodgkin-Huxley model. To implement slow-adapting power-law dynamics of the gating variables of the potassium, n, and sodium, m and h, conductances we used fractional derivatives of order η≤1. The fractional derivatives were used to solve the kinetic equations of each gate. We systematically classified the properties of each gate as a function of η. We then tested if the full model could generate action potentials with the different power-law behaving gates. Finally, we studied the patterns of action potential that emerged in each case. Our results show the model produces a wide range of action potential shapes and spiking patterns in response to constant current stimulation as a function of η. In comparison with the classical model, the action potential shapes for power-law behaving potassium conductance (n gate) showed a longer peak and shallow hyperpolarization; for power-law activation of the sodium conductance (m gate), the action potentials had a sharp rise time; and for power-law inactivation of the sodium conductance (h gate) the spikes had wider peak that for low values of η replicated pituitary- and cardiac-type action potentials. With all physiological parameters fixed a wide range of spiking patterns emerged as a function of the value of the constant input current and η, such as square wave bursting, mixed mode oscillations, and pseudo-plateau potentials. Our analyses show that the intrinsic memory trace of the fractional derivative provides a negative feedback mechanism between the voltage trace and the activity of the power-law behaving gate variable. As a consequence, power-law behaving conductances result in an increase in the number of spiking patterns a neuron can generate and, we propose, expand the computational capacity of the neuron. PMID:26937967

  17. The syllabic bridge: the first step in learning spelling-to-sound correspondences*.

    PubMed

    Doignon-Camus, Nadege; Zagar, Daniel

    2014-09-01

    It is widely agreed that learning to read starts with the establishment of letter-to-phoneme correspondences. However, it is also widely agreed that prereaders do not have access to phoneme units. Here we show that the building of associations between letters and syllables, which we call the 'syllabic bridge', might be a faster and more direct way of learning spelling-to-sound correspondences in French. After a few minutes of exposure, prereaders are able to learn the statistical properties of letter co-occurrences. Statistical learning is boosted by explicit instructions about the associations between letter clusters and syllables. Building the syllabic bridge from available phonological syllables and frequent letter clusters may therefore be the first step in learning to read.

  18. Letters from ainsworth: contesting the 'organization' of attachment.

    PubMed

    Landa, Sophie; Duschinsky, Robbie

    2013-05-01

    As Main (1999) noted in her obituary for Mary Ainsworth, 'she was interacting weekly by letter and manuscript with her mentor and friend, John Bowlby, and their academic correspondence formed an important part of her, and implicitly our, life.' These letters of Ainsworth to John Bowlby during the 1980s, available in the Wellcome Trust Library in London, contain valuable reflections on the work of her pupils to extend her system of classifying infant behaviour in the Strange Situation Procedure. Mary Main proposed a D classification and interpreted such behaviour as a breakdown in an ABC strategy caused by a conflict between a disposition to approach and flee from the caregiver. Patricia Crittenden extended the subtypes of A and C, using a developmental model of information processing, and observed that they could be used together in A/C combinations. These letters offer insight into Ainsworth's intellectual rationale for encouraging both Main and Crittenden in their conflicting endeavours.

  19. Differences between Good and Poor Child Writers on fMRI Contrasts for Writing Newly Taught and Highly Practiced Letter Forms

    ERIC Educational Resources Information Center

    Richards, Todd L.; Berninger, Virginia W.; Stock, Pat; Altemeier, Leah; Trivedi, Pamala; Maravilla, Kenneth R.

    2011-01-01

    During fMRI imaging, 12 good and 8 poor writers aged 11 wrote a newly taught pseudoletter and a highly practiced letter. Both letters were formed from the same components, but the pseudoletter had a novel configuration not corresponding to a written English letter form. On the first fMRI contrast between the newly taught pseudoletter and highly…

  20. The Harvard Education Letter, 1996.

    ERIC Educational Resources Information Center

    Miller, Edward Ed.; Graves-Desai, Kelly, Ed.; Maloney, Karen, Ed.

    1996-01-01

    This document is comprised of volume 12 of the Harvard Education Letter, published bimonthly and addressing current issues in elementary-secondary education. Articles in this volume include the following: (1) January-February--"Early Reports From Kentucky on Cash Rewards for 'Successful' Schools Reveal Many Problems" (Miller), "New…

  1. The Harvard Education Letter, 1995.

    ERIC Educational Resources Information Center

    Miller, Edward, Ed.

    1995-01-01

    This document is comprised of volume 11 of the Harvard Education Letter, published bimonthly and addressing current issues in elementary and secondary education. Articles in the volume's six issues are: (1) January-February--"The Old Model of Staff Development Survives in a World Where Everything Else Has Changed" (Miller), "Giving Voice to Our…

  2. Curriculum Vitae and Related Letters.

    ERIC Educational Resources Information Center

    Peterson, Sharyl Bender

    This booklet, which was developed by a college career center, explains the purpose of and procedures for writing curriculum vitae (CV) and related letters. The following topics are covered: when a CV is appropriate, points to consider when writing a CV, items usually included, possible sections to include in a CV, and steps in writing cover…

  3. The Harvard Education Letter, 1997.

    ERIC Educational Resources Information Center

    Graves-Desai, Kelly, Ed.; Maloney, Karen, Ed.

    1997-01-01

    This document is comprised of volume 13 of the Harvard Education Letter, published bimonthly and addressing current issues in elementary and secondary education. Articles in the six issues of this volume include: (1) January-February --"Making Detracking Work" (Lynn and Wheelock), "Developing a Culture of High Expectations for…

  4. Letter to the next President

    ERIC Educational Resources Information Center

    Rotherham, Andrew J.; Mikuta, Julie; Freeland, Julia

    2008-01-01

    This article takes the form of a letter to the 44th president of the United States, urging the president to pursue an aggressive agenda to improve teacher quality. The authors assert that because teacher quality is the single most important factor shown to impact student outcomes, the next administration must dedicate resources to human capital…

  5. "The Scarlet Letter". [Lesson Plan].

    ERIC Educational Resources Information Center

    Discovery Communications, Inc., Bethesda, MD.

    Based on Nathaniel Hawthorne's novel "The Scarlet Letter," this lesson plan presents activities designed to help students understand that the ending of a novel does not resolve all of the questions that may occur to readers; and that readers may imagine characters living out their lives beyond the ending the author gave to a novel. The main…

  6. The Harvard Education Letter, 1998.

    ERIC Educational Resources Information Center

    Graves-Desai, Kelly, Ed.; Eaton, Susan, Ed.; Walser, Nancy, Ed.

    1998-01-01

    This document is comprised of volume 14 of the Harvard Education Letter, published bimonthly and addressing current issues in elementary and secondary education. Articles in the six issues of this volume include the following: (1) January-February--"Multi-Age Classrooms: An Age-Old Grouping Method Is Still Evolving" (Walser), "Teachers Wanted:…

  7. Resource Letter RC-1: Cosmology

    ERIC Educational Resources Information Center

    Ryan, Michael P., Jr.; Shepley, L. C.

    1976-01-01

    This is one of a series of resource letters on different topics intended to guide college physicists, astronomers, and other scientists to some of the literature and other teaching aids that may help improve course content in specified fields. (Author/CP)

  8. Resource Letter N-1: Nanotechnology

    NASA Astrophysics Data System (ADS)

    Cela, Devin; Dresselhaus, Mildred; Helen Zeng, Tingying; Terrones, Mauricio; Souza Filho, Antonio G.; Ferreira, Odair P.

    2014-01-01

    This Resource Letter provides a guide to the literature on Nanotechnology. Journal articles, books, websites, and other documents are cited on the following topics: attributes of various types of nanomaterials, nanotechnology in the context of different academic fields, and the effects of nanotechnology on society.

  9. Resumes, Applications, and Cover Letters

    ERIC Educational Resources Information Center

    Crosby, Olivia

    2009-01-01

    Good resumes, applications, and cover letters broadcast one's abilities. They tell employers how one's qualifications match a job's responsibilities. If these critical preliminaries are constructed well, one has a better chance of landing interviews--and, eventually, a job. This article provides some guidelines for creating resumes and cover…

  10. Letters from a Nightingale nurse.

    PubMed

    Denny, E

    1996-01-01

    Mary Cadbury was one of six daughters in a wealthy Birmingham family, all of whom took up professional or unpaid philanthropic work. In 1873 Mary began nurse training at the Nightingale School, St Thomas's Hospital, and regularly sent letters to family and friends, which provide a graphic account of the experience of a nurse in the latter half of the nineteenth century.

  11. Letter to Russia

    SciTech Connect

    Tobin, J G

    2012-03-15

    find it puzzling that the authors nonetheless claim in their conclusions that 'An evaluation of state occupations supports the proposal that the occupation of the 5f levels in bulk Pu must be near 5'. Apart from the aforementioned conceptual inconsistencies, there are a number of more technical aspects that are not discussed in sufficient detail. Among these are: (1) The authors use LDA to approximate the electron correlations. A lively debate takes place in the literature whether this approximation can adequately describe the electronic structure of Pu metal or not, yet the authors do not discuss the choice of the approximation at all, which they should, in my opinion. They should also specify if their solutions are spin polarized or whether they use spin-restricted LDA. (2) The quality of the employed basis set is not clear. Are the results converged with respect to the basis size? What is the estimated magnitude of the residual errors? (3) There are statements in the manuscript indicating that the cluster calculations depend somehow on the calculations of the diatomic molecule. Namely: 'Underpinning these calculations, there is a geometry optimization of diatomic molecules...' and 'Underlying the Pu cluster simulations is the calculation of the electronic structure of a Pu2 dimer with the bond length 3.28 {angstrom} corresponding to the inter-atomic distances in delta-Pu.' What does this underpinning/underlying mean in more technical terms? What role does the geometry optimization play when the cluster calculations seem to be performed at a fixed geometry corresponding to the delta-Pu? Lastly, the manuscript contains a lot of material that was previously (and often multiple times) published elsewhere, including the Physical Review journals. For instance, the experimental part of Fig. 2 was shown already in Refs. 26, 27 and 28 in essentially the same graphical form; the top part of Fig. 9 appeared in Refs. 19, 4 and in PRL 90, 196404 (2003). I think that reprinting

  12. Letters of Reprimand: The Important Questions.

    ERIC Educational Resources Information Center

    Zirkel, Perry A.; Gluckman, Ivan B.

    1986-01-01

    Outlines two legal cases involving letters of reprimand written by administrators and put in teachers' files. Shows how in these cases the letters did not constitute defamation or a violation of First or Fourteenth Amendment rights. (MD)

  13. 7 CFR 1773.33 - Management letter.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 12 2011-01-01 2011-01-01 false Management letter. 1773.33 Section 1773.33... AGRICULTURE (CONTINUED) POLICY ON AUDITS OF RUS BORROWERS RUS Reporting Requirements § 1773.33 Management letter. The CPA must prepare a management letter that includes, at a minimum, comments on: (a)...

  14. 7 CFR 1773.33 - Management letter.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 12 2010-01-01 2010-01-01 false Management letter. 1773.33 Section 1773.33... AGRICULTURE (CONTINUED) POLICY ON AUDITS OF RUS BORROWERS RUS Reporting Requirements § 1773.33 Management letter. The CPA must prepare a management letter that includes, at a minimum, comments on: (a)...

  15. 24 CFR 200.1505 - Warning letter.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... URBAN DEVELOPMENT GENERAL INTRODUCTION TO FHA PROGRAMS Multifamily Accelerated Processing (MAP): MAP... letter, which specifies problems or violations identified by HUD, to a MAP lender. (b) Effect of warning letter. The warning letter: (1) Does not suspend a lender's MAP privileges; (2) May impose a higher...

  16. 24 CFR 200.1505 - Warning letter.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... URBAN DEVELOPMENT GENERAL INTRODUCTION TO FHA PROGRAMS Multifamily Accelerated Processing (MAP): MAP... letter, which specifies problems or violations identified by HUD, to a MAP lender. (b) Effect of warning letter. The warning letter: (1) Does not suspend a lender's MAP privileges; (2) May impose a higher...

  17. 24 CFR 200.1505 - Warning letter.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... URBAN DEVELOPMENT GENERAL INTRODUCTION TO FHA PROGRAMS Multifamily Accelerated Processing (MAP): MAP... letter, which specifies problems or violations identified by HUD, to a MAP lender. (b) Effect of warning letter. The warning letter: (1) Does not suspend a lender's MAP privileges; (2) May impose a higher...

  18. 24 CFR 200.1505 - Warning letter.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... URBAN DEVELOPMENT GENERAL INTRODUCTION TO FHA PROGRAMS Multifamily Accelerated Processing (MAP): MAP... letter, which specifies problems or violations identified by HUD, to a MAP lender. (b) Effect of warning letter. The warning letter: (1) Does not suspend a lender's MAP privileges; (2) May impose a higher...

  19. 24 CFR 200.1505 - Warning letter.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... URBAN DEVELOPMENT GENERAL INTRODUCTION TO FHA PROGRAMS Multifamily Accelerated Processing (MAP): MAP... letter, which specifies problems or violations identified by HUD, to a MAP lender. (b) Effect of warning letter. The warning letter: (1) Does not suspend a lender's MAP privileges; (2) May impose a higher...

  20. 7 CFR 1773.33 - Management letter.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 12 2014-01-01 2013-01-01 true Management letter. 1773.33 Section 1773.33 Agriculture... (CONTINUED) POLICY ON AUDITS OF RUS BORROWERS RUS Reporting Requirements § 1773.33 Management letter. The CPA must prepare a management letter that includes, at a minimum, comments on: (a) Audit procedures....

  1. 7 CFR 1773.33 - Management letter.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 12 2013-01-01 2013-01-01 false Management letter. 1773.33 Section 1773.33... AGRICULTURE (CONTINUED) POLICY ON AUDITS OF RUS BORROWERS RUS Reporting Requirements § 1773.33 Management letter. The CPA must prepare a management letter that includes, at a minimum, comments on: (a)...

  2. 7 CFR 1773.33 - Management letter.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 12 2012-01-01 2012-01-01 false Management letter. 1773.33 Section 1773.33... AGRICULTURE (CONTINUED) POLICY ON AUDITS OF RUS BORROWERS RUS Reporting Requirements § 1773.33 Management letter. The CPA must prepare a management letter that includes, at a minimum, comments on: (a)...

  3. Making Routine Letters Have Positive Effects.

    ERIC Educational Resources Information Center

    Walsh, S. M.

    While few business people dispute the importance of carefully crafting persuasive, demanding, conciliatory, and bad-news letters, the regular flow of routine communications receives very little meaningful consideration or scrutiny. These routine communications (letters, inquiries, requests, collection letters, complaints, confirmations,…

  4. Beyond Zebra: Preschoolers' Knowledge about Letters.

    ERIC Educational Resources Information Center

    Treiman, Rebecca; Richmond-Welty, E. Daylene; Tincoff, Ruth

    1997-01-01

    Argues that an important type of child knowledge about letters is knowledge of the phonological structure of the letters' names in English. Concludes that learning the alphabet forms the basis for generalizations about the structure of letter names. (22 references) (Author/CK)

  5. 48 CFR 3016.603 - Letter contracts.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 7 2013-10-01 2012-10-01 true Letter contracts. 3016.603... ACQUISITION REGULATION (HSAR) CONTRACT METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Time-and-Materials, Labor-Hour, and Letter Contracts 3016.603 Letter contracts....

  6. 48 CFR 3416.603 - Letter contracts.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 7 2013-10-01 2012-10-01 true Letter contracts. 3416.603... CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Time-and-Materials, Labor-Hour, and Letter Contracts 3416.603 Letter contracts....

  7. Are Letter Detection and Proofreading Tasks Equivalent?

    ERIC Educational Resources Information Center

    Saint-Aubin, Jean; Losier, Marie-Claire; Roy, Macha; Lawrence, Mike

    2015-01-01

    When readers search for misspellings in a proofreading task or for a letter in a letter detection task, they are more likely to omit function words than content words. However, with misspelled words, previous findings for the letter detection task were mixed. In two experiments, the authors tested the functional equivalence of both tasks. Results…

  8. 49 CFR 107.309 - Warning letters.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 2 2012-10-01 2012-10-01 false Warning letters. 107.309 Section 107.309... PROGRAM PROCEDURES Enforcement Compliance Orders and Civil Penalties § 107.309 Warning letters. (a) The Associate Administrator may issue a warning letter to any person whom the Associate Administrator...

  9. 17 CFR 38.711 - Warning letters.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 17 Commodity and Securities Exchanges 1 2014-04-01 2014-04-01 false Warning letters. 38.711... MARKETS Disciplinary Procedures § 38.711 Warning letters. Where a rule violation is found to have occurred, no more than one warning letter may be issued per rolling 12-month period for the same violation....

  10. 17 CFR 38.711 - Warning letters.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 17 Commodity and Securities Exchanges 1 2013-04-01 2013-04-01 false Warning letters. 38.711... MARKETS Disciplinary Procedures § 38.711 Warning letters. Where a rule violation is found to have occurred, no more than one warning letter may be issued per rolling 12-month period for the same violation....

  11. 19 CFR 354.7 - Charging letter.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 3 2010-04-01 2010-04-01 false Charging letter. 354.7 Section 354.7 Customs... VIOLATION OF AN ANTIDUMPING OR COUNTERVAILING DUTY ADMINISTRATIVE PROTECTIVE ORDER § 354.7 Charging letter. (a) Contents of Letter. The Deputy Under Secretary will initiate proceedings by issuing a...

  12. Written Communications Simulation: Write Me a Letter.

    ERIC Educational Resources Information Center

    North Carolina State Dept. of Public Instruction, Raleigh. Div. of Vocational Education.

    This simulation is intended for use as a culminating activity after students have been exposed to personal and/or business letter writing, use of reference manuals, typing of letters, mailing procedures, typing of numbers, punctuation practice, and filing procedures. Stated objectives are to enable students to type a mailable letter; to inspect,…

  13. Letter Writing in the College Classroom.

    ERIC Educational Resources Information Center

    Fredericksen, Elaine

    2000-01-01

    Suggests that beginning writers can improve skills when they exchange letters with peers, teachers, and others. Offers a brief historical perspective on the use of letters as a pedagogical device. Outlines current applications of letter writing and exchanges in: English as a second language; technical and business writing; composition and…

  14. Gotcha, Grandpa! More Letters to Grandchildren.

    ERIC Educational Resources Information Center

    Smith, Carl B.

    Letters and notes between grandchildren and grandparents can bring mutual benefits. This book shows grandparents how to start writing, what to write about, how to make writing fun and easy, how to get replies, and how to write memorable letters. The book, a sequel to "With Love, Grandma" (1998), provides sample letters on numerous topics…

  15. What Do Letter Migration Errors Reveal About Letter Position Coding in Visual Word Recognition?

    ERIC Educational Resources Information Center

    Davis, Colin J.; Bowers, Jeffrey S.

    2004-01-01

    Dividing attention across multiple words occasionally results in misidentifications whereby letters apparently migrate between words. Previous studies have found that letter migrations preserve within-word letter position, which has been interpreted as support for position-specific letter coding. To investigate this issue, the authors used word…

  16. An Attempt to Simulate Letter-by-Letter Dyslexia in Normal Readers

    ERIC Educational Resources Information Center

    Fiset, Stephanie; Arguin, Martin; Fiset, Daniel

    2006-01-01

    We attempted to simulate the main features of letter-by-letter (LBL) dyslexia in normal readers through stimulus degradation (i.e. contrast reduction and removal of high spatial frequencies). The results showed the word length and the letter confusability effects characteristic of LBL dyslexia. However, the interaction of letter confusability and…

  17. Learning Letter Names and Sounds: Effects of Instruction, Letter Type, and Phonological Processing Skill

    ERIC Educational Resources Information Center

    Piasta, Shayne B.; Wagner, Richard K.

    2010-01-01

    Preschool-age children (N = 58) were randomly assigned to receive instruction in letter names and sounds, letter sounds only, or numbers (control). Multilevel modeling was used to examine letter name and sound learning as a function of instructional condition and characteristics of both letters and children. Specifically, learning was examined in…

  18. 50 years of JETP Letters

    NASA Astrophysics Data System (ADS)

    Pastukhov, V. P.

    2015-04-01

    This paper briefly traces the 50-year history of the journal Pis'ma v Zhurnal Eksperimental'noi i Teoreticheskoi Fiziki (JETP Letters), whose first issue was published on 1 April 1965. The journal is intended for a wide circle of physicists-readers as a fast publication channel for short communications on new results from research of the highest significance and highest priority in all areas of experimental and theoretical physics. Today, the journal celebrates numerous important contributions to the development of physics both in Russia and worldwide. Over a historically short period, JETP Letters developed into a highly authoritative and influential source for physicists engaged in a wide range of fields. Due to the wise and well-timed editorial policy, the journal continues to retain its leadership position, despite the difficulties the entire science periodical literature - and indeed the whole of science - is currently experiencing in Russia.

  19. Spatio-temporal properties of letter crowding

    PubMed Central

    Chung, Susana T. L.

    2016-01-01

    Crowding between adjacent letters has been investigated primarily as a spatial effect. The purpose of this study was to investigate the spatio-temporal properties of letter crowding. Specifically, we examined the systematic changes in the degradation effects in letter identification performance when adjacent letters were presented with a temporal asynchrony, as a function of letter separation and between the fovea and the periphery. We measured proportion-correct performance for identifying the middle target letter in strings of three lowercase letters at the fovea and 10° in the inferior visual field, for a range of center-to-center letter separations and a range of stimulus onset asynchronies (SOA) between the target and flanking letters (positive SOAs: target preceded flankers). As expected, the accuracy for identifying the target letters reduces with decreases in letter separation. This crowding effect shows a strong dependency on SOAs, such that crowding is maximal between 0 and ∼100 ms (depending on conditions) and diminishes for larger SOAs (positive or negative). Maximal crowding does not require the target and flanking letters to physically coexist for the entire presentation duration. Most importantly, crowding can be minimized even for closely spaced letters if there is a large temporal asynchrony between the target and flankers. The reliance of letter identification performance on SOAs and how it changes with letter separations imply that the crowding effect can be traded between space and time. Our findings are consistent with the notion that crowding should be considered as a spatio-temporal, and not simply a spatial, effect. PMID:27088895

  20. Spatio-temporal properties of letter crowding.

    PubMed

    Chung, Susana T L

    2016-01-01

    Crowding between adjacent letters has been investigated primarily as a spatial effect. The purpose of this study was to investigate the spatio-temporal properties of letter crowding. Specifically, we examined the systematic changes in the degradation effects in letter identification performance when adjacent letters were presented with a temporal asynchrony, as a function of letter separation and between the fovea and the periphery. We measured proportion-correct performance for identifying the middle target letter in strings of three lowercase letters at the fovea and 10° in the inferior visual field, for a range of center-to-center letter separations and a range of stimulus onset asynchronies (SOA) between the target and flanking letters (positive SOAs: target preceded flankers). As expected, the accuracy for identifying the target letters reduces with decreases in letter separation. This crowding effect shows a strong dependency on SOAs, such that crowding is maximal between 0 and ∼100 ms (depending on conditions) and diminishes for larger SOAs (positive or negative). Maximal crowding does not require the target and flanking letters to physically coexist for the entire presentation duration. Most importantly, crowding can be minimized even for closely spaced letters if there is a large temporal asynchrony between the target and flankers. The reliance of letter identification performance on SOAs and how it changes with letter separations imply that the crowding effect can be traded between space and time. Our findings are consistent with the notion that crowding should be considered as a spatio-temporal, and not simply a spatial, effect.

  1. William Stewart Halsted: Letters to a Young Female Admirer

    PubMed Central

    Cameron, John L.; Gordon, Toby A.; Kehoe, Marjorie Winslow; McCall, Nancy

    2001-01-01

    Objective To present the first new information in the past 25 years concerning the life of Dr. William Stewart Halsted. This paper reports on recently discovered personal correspondence of Dr. Halsted, beginning at age 66, to a young lady, Elizabeth Blanchard Randall, 40 years his junior. Summary Background Data Dr. William Stewart Halsted is generally considered the most important and influential surgeon that this country has produced. During his Hopkins days in Baltimore (1886–1922) he was rather reclusive, and little is known of his personal life. He was married but had no children. Several biographies written by Halsted’s contemporaries constitute the bulk of what is known about Halsted’s personal life. Methods All extant letters from Dr. Halsted to Miss Randall were reviewed. Archival materials were consulted to understand the context for this friendship. The correspondence between Halsted and Randall took place during a 3-year period, although their acquaintance was probably long-standing. Results The letters reveal Dr. Halsted and Miss Randall’s great and warm affection for each other, despite their 40-year age difference. The letters have a playful nature absent in Halsted’s other correspondence. This relationship has not been previously noted. Conclusions Late in Halsted’s life, he developed a warm and affectionate relationship with a young lady 40 years his junior, as revealed in Halsted’s correspondence. Halsted’s warm, personal, and playful letters are in stark contrast to his biographers’ portrayals of him as a more serious and reclusive person. PMID:11685036

  2. Writing More Informative Letters of Reference

    PubMed Central

    Wright, Scott M; Ziegelstein, Roy C

    2004-01-01

    Writing a meaningful and valuable letter of reference is not an easy task. Several factors influence the quality of any letter of reference. First, the accuracy and reliability of the writer's impressions and judgment depend on how well he knows the individual being described. Second, the writer's frame of reference, which is determined by the number of persons at the same level that he has worked with, will impact the context and significance of his beliefs and estimations. Third, the letter-writing skills of the person composing the letter will naturally affect the letter. To support the other components of a candidate's application, a letter of reference should provide specific examples of how an individual's behavior or attitude compares to a reference group and should assess “intangibles” that are hard to glean from a curriculum vitae or from test scores. This report offers suggestions that should help physicians write more informative letters of reference. PMID:15109330

  3. The Lyttleton-Hoyle correspondence 1939-42

    NASA Astrophysics Data System (ADS)

    Mitton, S.

    2005-12-01

    Fred Hoyle started to collaborate with his older colleague Raymond Lyttleton in 1938. Hoyle's doctoral research had been in nuclear physics, and his supervisors were Rudolph Peierls and Paul Dirac. His first papers were in quantum electrodynamics. When Hoyle decided to change his research field to astronomy, Lyttleton acted as a mentor, and it was he who suggested that Hoyle should look at the physics of accretion. From late-1939, Lyttleton and Hoyle were both scientific civil servants drafted in for war work. They were in different establishments and could communicate only by the postal service. Some 70 letters from Lyttleton to Hoyle have survived, but we do not have any copies of Hoyle's correspondence. Many letters are undated, so it required detective work to assemble them in the correct sequence. The correspondence shows that Lyttleton played the senior role in determining what problems they should tackle, and in what order. Apart from the scientific content, these letters are remarkable for the sharp personal remarks Lyttleton makes of other colleagues, and particularly the Council of the Royal Astronomical Society. I make the suggestion that the poisonous and prolonged nature of the correspondence considerably influenced Hoyle's subsequent attitude to the establishment, to government-employed astronomers, and to the RAS. This was detrimental when Hoyle found, later in his career, that he would have to provide answers to these stakeholders. This research has been supported by St Edmund's College, Cambridge, UK.

  4. Letters

    NASA Astrophysics Data System (ADS)

    1999-01-01

    A Coordination Geometry Table by Francisco J. Arnáiz Re: article by D. Venkataraman, Y. Du, S. R. Wilson, K. A. Hirsch, P. Zhang, and J. S. Moore The authors reply Cut-Out Molecular Models by A. L. Silva, C. Fernandes, O. Wasterlain, S. Costa, and A. M. Mendes Re: article by R. J. Kashmar Kinetics Lesson for College Deans by Fred Hadley

  5. Letters

    NASA Astrophysics Data System (ADS)

    1999-11-01

    Survey of Binary Azeotropes by Paul C. Yates Re: article by R. J. Glinski, C. W. Smith, and J. B. Cooke Cheating Probabilities? Probably Not by David J. Miller Re: a criticism by C. Jonah and a note by G. T. Rizzuto and F. Walters trans-Cyclohexane-1,2-diamine by Richard S. Treptow Re: article by P. J. Walsh, D. K. Smith, and C. Castello Micropreparation of [RuH2PPh3)4] by Francisco J. Arnáiz Re: article by D. E. Linn, Jr. The author replies D. E. Linn's response follows

  6. Letters

    NASA Astrophysics Data System (ADS)

    1998-12-01

    Beer's Law: The Real Hazards by S. R. Logan Re: article by M. A. Muyskens and E. T. Sevy The author replies Photodimerization of Maleic Anhydride by Zhijun Zhang Re: article by D. Todd and M. Pickering (J. Chem. Educ. 1988, 65, 1100) Qual from a Different Viewpoint by Francisco J. Arnáiz Re: article by M. Laing (J. Chem. Educ. 1993, 70, 666)

  7. Letters

    NASA Astrophysics Data System (ADS)

    2000-02-01

    Inflection at the Triple Point by R. Thomas Myers Author's reply: Stephen J. Hawkes Correction Figure 1 of the article Using Overhead Projector to Simulate X-ray Diffraction Experiments by Veljko Dragojlovic (J. Chem. Educ. 1999, 76, 1240-1241) had the images for the red filter and the blue filter reversed. The correctly labeled images are shown below. These images are shown in color in the JCE Online PDF version of this article. Figure 2. Diffraction patterns obtained with (a) red filter, (b) blue filter, and (c) without a filter.

  8. Letters

    NASA Astrophysics Data System (ADS)

    1999-12-01

    Levels of Description in Chemistry by P. G. Nelson Re: articles by W. B. Jensen in June, July, and August of 1998. The author replies Inexpensive Variable Path-Length Cells for Discovery-Based Investigation of the Beer-Lambert Law by Jonathan Mitschele Re: article by S. A. Stewart and A. J. Sommer CD Spectroscope by Lanny Whitten Re: Classroom Activity (CD Light: An Introduction to Spectroscopy) Correction The Literature Cited section was unfortunately omitted from the October 1999 NSF Highlights column, "Organic Chemistry Course Development in a Forensic Science Program: Use of FT-NMR" by Ronald Callahan, Lawrence Kobilinsky and Robert Rothchild (J. Chem. Educ. 1999, 76, 1332-1333). The references are provided in the PDF version.

  9. Letters

    NASA Astrophysics Data System (ADS)

    1999-10-01

    Copper Content in Synthetic Copper Carbonate: A Statistical Comparison of Experimental and Expected Results by H. Gamsjäger and W. Preis Re: article by D. Sheeran The author replies The Amateur Mineral Chemist by Dana Martin Morong More on Double Replacement by George B. Kauffman Re: article by R. B. Martin

  10. Similar Sound Separation and Cumulative Introduction in Learning Letter-Sound Correspondences

    ERIC Educational Resources Information Center

    Carnine, Douglas W.

    1976-01-01

    Since similarity inhibits learning, children will have greater difficulty learning responses that are more similar to each other; the instructional procedure of separating similar sounds was evaluated in two experiments. (DMT)

  11. Teaching Letter-Sound Correspondence to Students with Moderate Intellectual Disabilities

    ERIC Educational Resources Information Center

    Flores, Margaret M.; Shippen, Margaret E.; Alberto, Paul; Crowe, Lee

    2004-01-01

    This study examined the efficacy of systematic and explicit instruction in phonic decoding for 6 elementary students with moderate intellectual disabilities. A multiple probe across behaviors with embedded changing conditions design was employed in order to analyze the effect of Direct Instruction on teaching the following skills with regard to…

  12. The letter: private text or public place? The Mattioli-Gesner controversy about the aconitum primum.

    PubMed

    Delisle, Candice

    2004-01-01

    From 1555 to 1565, Pietro Andrea Mattioli and Conrad Gesner were locked in controversy over the veracity of Mattioli's picture of aconitum primum. This dispute led to numerous vehement publications and to intensive exchanges of letters, not only between the protagonists but also within their own and sometimes inter-connected networks of correspondence. This dispute illustrates how 16th-century scholars played upon the ambiguous place of these letters between private and public space to deal with controversy in the Republic of Letters.

  13. Synesthesia for manual alphabet letters and numeral signs in second-language users of signed languages.

    PubMed

    Atkinson, Joanna; Lyons, Tanya; Eagleman, David; Woll, Bencie; Ward, Jamie

    2016-08-01

    Many synesthetes experience colors when viewing letters or digits. We document, for the first time, an analogous phenomenon among users of signed languages who showed color synesthesia for fingerspelled letters and signed numerals. Four synesthetes experienced colors when they viewed manual letters and numerals (in two cases, colors were subjectively projected on to the hands). There was a correspondence between the colors experienced for written graphemes and their manual counterparts, suggesting that the development of these two types of synesthesia is interdependent despite the fact that these systems are superficially distinct and rely on different perceptual recognition mechanisms in the brain.

  14. [Hardware Implementation of Numerical Simulation Function of Hodgkin-Huxley Model Neurons Action Potential Based on Field Programmable Gate Array].

    PubMed

    Wang, Jinlong; Lu, Mai; Hu, Yanwen; Chen, Xiaoqiang; Pan, Qiangqiang

    2015-12-01

    Neuron is the basic unit of the biological neural system. The Hodgkin-Huxley (HH) model is one of the most realistic neuron models on the electrophysiological characteristic description of neuron. Hardware implementation of neuron could provide new research ideas to clinical treatment of spinal cord injury, bionics and artificial intelligence. Based on the HH model neuron and the DSP Builder technology, in the present study, a single HH model neuron hardware implementation was completed in Field Programmable Gate Array (FPGA). The neuron implemented in FPGA was stimulated by different types of current, the action potential response characteristics were analyzed, and the correlation coefficient between numerical simulation result and hardware implementation result were calculated. The results showed that neuronal action potential response of FPGA was highly consistent with numerical simulation result. This work lays the foundation for hardware implementation of neural network.

  15. Anti-electromagnetic interference analysis of equivalent circuit of ion channel based on the Hodgkin-Huxley model

    NASA Astrophysics Data System (ADS)

    Chu, J.; Chang, X. L.; Zhao, M.; Man, M. H.; Yuan, L.; Wei, M.

    2013-03-01

    With the continuous improvement of circuit integration and working clock frequency in the electronic system, it is increasingly easy for the system to be affected by electromagnetic waves, and electromagnetic susceptibility and vulnerability become more severe. However, living beings in nature have shown extraordinary compatibility, immunity and adaptability to the electromagnetism at the same time. In addition, the ion channel on the neuron cytomembrane is a typical representation of "bioelectrical immunity". So the Hodgkin-Huxley circuit model with one capacitor in parallel with some power supplies and resistors was adopted to simulate the ion channel on the neuron cytomembrane. Through analysis, the circuit model can be used to simulate some electrical characteristics of biological neuron cells, and then acquire a certain level of anti-electromagnetic interference ability. This method will be useful for improving the reliability, compatibility and anti-interference capability of the electronic system in the complicated electromagnetic environment.

  16. Effects of the spike timing-dependent plasticity on the synchronisation in a random Hodgkin-Huxley neuronal network

    NASA Astrophysics Data System (ADS)

    Borges, R. R.; Borges, F. S.; Lameu, E. L.; Batista, A. M.; Iarosz, K. C.; Caldas, I. L.; Viana, R. L.; Sanjuán, M. A. F.

    2016-05-01

    In this paper, we study the effects of spike timing-dependent plasticity on synchronisation in a network of Hodgkin-Huxley neurons. Neuron plasticity is a flexible property of a neuron and its network to change temporarily or permanently their biochemical, physiological, and morphological characteristics, in order to adapt to the environment. Regarding the plasticity, we consider Hebbian rules, specifically for spike timing-dependent plasticity (STDP), and with regard to network, we consider that the connections are randomly distributed. We analyse the synchronisation and desynchronisation according to an input level and probability of connections. Moreover, we verify that the transition for synchronisation depends on the neuronal network architecture, and the external perturbation level.

  17. FROM THE HISTORY OF PHYSICS: Correspondence between G A Gamow and P L Kapitza

    NASA Astrophysics Data System (ADS)

    Frenkel', Viktor Ya

    1994-08-01

    The letters exchanged between Peter Kapitza and George Gamow are published here for the first time. The correspondence throws light on the active support accorded by Kapitza to his Russian colleagues and on his work as the coeditor of a prestigious series of physics monographs published by Clarendon Press, Oxford. Gamow comes over in his letters, relating to one of the most interesting periods of his creative activity (1929 - 1934), in full blaze of his personality.

  18. ["Professor is well". The correspondence between Max Schur and Marie Bonaparte].

    PubMed

    Stouten, Hanna

    2012-01-01

    The correspondence between Freud's doctor and his "Princess" spans the period 1929-1962, and comprises over 90 letters, mostly concerned with Freud's health but also touching upon Schur's permanent dilemma--to emigrate or to stay with Freud--and upon the dire situation of his family and friends on behalf of whom he appeals to Marie for help. After Freud's death the letters change in focus.

  19. Updated Principle of Corresponding States

    ERIC Educational Resources Information Center

    Ben-Amotz, Dor; Gift, Alan D.; Levine, R. D.

    2004-01-01

    The rule of corresponding states, which shows the connection between the thermodynamic properties of various liquids is re-examined. The overall likeness is observed by using an updated scaling technique of Lennard-Jones corresponding states (LJ-CS).

  20. Teacher candidates' mastery of phoneme-grapheme correspondence: massed versus distributed practice in teacher education.

    PubMed

    Sayeski, Kristin L; Earle, Gentry A; Eslinger, R Paige; Whitenton, Jessy N

    2017-04-01

    Matching phonemes (speech sounds) to graphemes (letters and letter combinations) is an important aspect of decoding (translating print to speech) and encoding (translating speech to print). Yet, many teacher candidates do not receive explicit training in phoneme-grapheme correspondence. Difficulty with accurate phoneme production and/or lack of understanding of sound-symbol correspondence can make it challenging for teachers to (a) identify student errors on common assessments and (b) serve as a model for students when teaching beginning reading or providing remedial reading instruction. For students with dyslexia, lack of teacher proficiency in this area is particularly problematic. This study examined differences between two learning conditions (massed and distributed practice) on teacher candidates' development of phoneme-grapheme correspondence knowledge and skills. An experimental, pretest-posttest-delayed test design was employed with teacher candidates (n = 52) to compare a massed practice condition (one, 60-min session) to a distributed practice condition (four, 15-min sessions distributed over 4 weeks) for learning phonemes associated with letters and letter combinations. Participants in the distributed practice condition significantly outperformed participants in the massed practice condition on their ability to correctly produce phonemes associated with different letters and letter combinations. Implications for teacher preparation are discussed.

  1. [Protestant clergymen among Hahnemann's clientele. Patient histories in letters].

    PubMed

    Kreher, Simone; Schlott, Melanie; Schlott, Thilo

    2016-01-01

    As part of the research project, developments in the history of science and in the regional and ecclesiastic history of the late feudal petty state of Köthen-Anhalt have been assessed and numerous documents of the Nagel and Mühlenbein family histories examined that place the transcribed patient letters of the two Protestant clergymen within the context of the Hahnemann Archives. These findings complement and extend previous insights into Hahnemann's Köthen clientele, especially when it comes to the structure and milieu of the local clerical elite. Inspired by the interpretive methods of sequential textual analysis, form and content of the letters of the two clergymen and their relatives were also investigated as methodically structured lines of communication. The body of sources published here presents--embedded in the body-image (of sickness and health) prevalent at the time--the medical cultures of educated patients as well as the increasingly professionalized medical practices of Samuel Hahnemann in a flourishing urban doctor's surgery. The correspondence between the pastors Albert Wilhelm Gotthilf Nagel (1796-1835) and August Carl Ludwig Georg Mühlenbein (1797-1866), presented here in a standard edition, has been investigated at Fulda University as part of the project 'Homöopathisches Medicinieren zwischen alltäglicher Lebensführung und professioneller Praxis' ('Homeopathic medicine between everyday use and professional practice'). Of the altogether 78 transcribed documents, 53 are letters written by either of the two pastors, 16 are patient journals by Samuel Hahnemann, 9 letters by the pastors' wives and Mühlenbein's mother. The two series of letters, originally composed between 1831 and 1833 in old German cursive script, can now be used as sources for research into the history of homeopathy.

  2. Letter to the Editor on Robert Yaes's Letter

    NASA Technical Reports Server (NTRS)

    Krisher, T. P.

    1993-01-01

    In his letter on page 13 of the March 1993 issue, Robert Yaes raised the question of whether the existence of the cosmic microwave background (CMB), now observed so precisely with COBE, is compatible with the principle of relativity: The laws by which the states of physical systems undergo change are not affected, whether these changes of state be referred to the one or other of two systems of coordinates in uniform translatory motion. Although I do not claim to provide an xpertresponse to this question, as desired by Yaes, it is my understanding that the principle of relativity is not necessarily violated by the mere existence of a universal reference frame. The laws of physics can still be invariant under some transformation of coordinates. This transformation is not specified by the principle of relativity itself, although we have discovered so far that Nature respects Lorentz invariance (principle of the constancy of the velocity of light).

  3. 1999 Children's Health Protection Advisory Committee Letters

    EPA Pesticide Factsheets

    These letters, most of which are addressed to Administrator Carol Browner, are regarding a children's longitudinal cohort study, acute dietary exposure, cancer risk assessment, and residential exposure assessments.

  4. Letter report: Evaluation of dryer/calciner technologies for testing

    SciTech Connect

    Sevigny, G.

    1996-02-01

    This letter report describes some past experiences on the drying and calcination of radioactive materials or corresponding simulants; and the information needed from testing. The report also includes an assessment of informational needs including possible impacts to a full-scale plant. This includes reliability, maintenance, and overall size versus throughput. Much of the material was previously compiled and reported by Mike Elliott of PNL {open_quotes}Melter Performance Assessment{close_quotes} and Larry Eisenstatt of SEG on contract to WHC in a letter to Rod Powell. Also, an annotated bibliography was prepared by Reagan Seymour of WHC. Descriptions of the drying and calciner technologies, development status, advantages and disadvantages of using a WFE or calciner, and recommendations for future testing are discussed in this report.

  5. Effect of Orthographic Processes on Letter Identity and Letter-Position Encoding in Dyslexic Children

    PubMed Central

    Reilhac, Caroline; Jucla, Mélanie; Iannuzzi, Stéphanie; Valdois, Sylviane; Démonet, Jean-François

    2012-01-01

    The ability to identify letters and encode their position is a crucial step of the word recognition process. However and despite their word identification problem, the ability of dyslexic children to encode letter identity and letter-position within strings was not systematically investigated. This study aimed at filling this gap and further explored how letter identity and letter-position encoding is modulated by letter context in developmental dyslexia. For this purpose, a letter-string comparison task was administered to French dyslexic children and two chronological age (CA) and reading age (RA)-matched control groups. Children had to judge whether two successively and briefly presented four-letter strings were identical or different. Letter-position and letter identity were manipulated through the transposition (e.g., RTGM vs. RMGT) or substitution of two letters (e.g., TSHF vs. TGHD). Non-words, pseudo-words, and words were used as stimuli to investigate sub-lexical and lexical effects on letter encoding. Dyslexic children showed both substitution and transposition detection problems relative to CA-controls. A substitution advantage over transpositions was only found for words in dyslexic children whereas it extended to pseudo-words in RA-controls and to all type of items in CA-controls. Letters were better identified in the dyslexic group when belonging to orthographically familiar strings. Letter-position encoding was very impaired in dyslexic children who did not show any word context effect in contrast to CA-controls. Overall, the current findings point to a strong letter identity and letter-position encoding disorder in developmental dyslexia. PMID:22661961

  6. Texture-Based Correspondence Display

    NASA Technical Reports Server (NTRS)

    Gerald-Yamasaki, Michael

    2004-01-01

    Texture-based correspondence display is a methodology to display corresponding data elements in visual representations of complex multidimensional, multivariate data. Texture is utilized as a persistent medium to contain a visual representation model and as a means to create multiple renditions of data where color is used to identify correspondence. Corresponding data elements are displayed over a variety of visual metaphors in a normal rendering process without adding extraneous linking metadata creation and maintenance. The effectiveness of visual representation for understanding data is extended to the expression of the visual representation model in texture.

  7. Letter Names and Phonological Awareness Help Children to Learn Letter-Sound Relations

    ERIC Educational Resources Information Center

    Cardoso-Martins, Claudia; Mesquita, Tereza Cristina Lara; Ehri, Linnea

    2011-01-01

    Two experimental training studies with Portuguese-speaking preschoolers in Brazil were conducted to investigate whether children benefit from letter name knowledge and phonological awareness in learning letter-sound relations. In Experiment 1, two groups of children were compared. The experimental group was taught the names of letters whose sounds…

  8. Disentangling the Developmental Trajectories of Letter Position and Letter Identity Coding Using Masked Priming

    ERIC Educational Resources Information Center

    Kezilas, Yvette; McKague, Meredith; Kohnen, Saskia; Badcock, Nicholas A.; Castles, Anne

    2017-01-01

    Masked transposed-letter (TL) priming effects have been used to index letter position processing over the course of reading development. Whereas some studies have reported an increase in TL priming over development, others have reported a decrease. These findings have led to the development of 2 somewhat contradictory accounts of letter position…

  9. Letter Names: Effect on Letter Saying, Spelling, and Word Recognition in Hebrew.

    ERIC Educational Resources Information Center

    Levin, Iris; Patel, Sigal; Margalit, Tamar; Barad, Noa

    2002-01-01

    Examined whether letter names, which bridge the gap between oral and written language among English speaking children, have a similar function in Hebrew. In findings from studies of Israeli kindergartners and first graders, children were found to rely on letter names in performing a number of letter saying, spelling, and word recognition tasks.…

  10. Osler and the Infected Letter

    PubMed Central

    2005-01-01

    The spread of infectious agents through the mail has concerned public health officials for 5 centuries. The dissemination of anthrax spores in the US mail in 2001 was a recent example. In 1901, two medical journals reported outbreaks of smallpox presumably introduced by letters contaminated with variola viruses. The stability and infectivity of the smallpox virus are reviewed from both a historical (anecdotal) perspective and modern virologic studies. Bubonic plague was the contagious disease that led to quarantines as early as the 14th century in port cities in southern Europe. Later, smallpox, cholera, typhus, and yellow fever were recognized as also warranting quarantine measures. Initially, attempts were made to decontaminate all goods imported from pestilential areas, particularly mail. Disinfection of mail was largely abandoned in the early 20th century with newer knowledge about the spread and stability of these 5 infectious agents. PMID:15890120

  11. The influence of reading expertise in mirror-letter perception: Evidence from beginning and expert readers

    PubMed Central

    Duñabeitia, Jon Andoni; Dimitropoulou, María; Estévez, Adelina; Carreiras, Manuel

    2013-01-01

    The visual word recognition system recruits neuronal systems originally developed for object perception which are characterized by orientation insensitivity to mirror reversals. It has been proposed that during reading acquisition beginning readers have to “unlearn” this natural tolerance to mirror reversals in order to efficiently discriminate letters and words. Therefore, it is supposed that this unlearning process takes place in a gradual way and that reading expertise modulates mirror-letter discrimination. However, to date no supporting evidence for this has been obtained. We present data from an eye-movement study that investigated the degree of sensitivity to mirror-letters in a group of beginning readers and a group of expert readers. Participants had to decide which of the two strings presented on a screen corresponded to an auditorily presented word. Visual displays always included the correct target word and one distractor word. Results showed that those distractors that were the same as the target word except for the mirror lateralization of two internal letters attracted participants’ attention more than distractors created by replacement of two internal letters. Interestingly, the time course of the effects was found to be different for the two groups, with beginning readers showing a greater tolerance (decreased sensitivity) to mirror-letters than expert readers. Implications of these findings are discussed within the framework of preceding evidence showing how reading expertise modulates letter identification. PMID:24273596

  12. A review of the diversity and evolution of photonic structures in butterflies, incorporating the work of John Huxley (The Natural History Museum, London from 1961 to 1990).

    PubMed

    Ingram, A L; Parker, A R

    2008-07-27

    The photonic structures of butterfly wings are among the most anatomically diverse of all those in nature, giving rise to an unrivalled display of structural colours. These have recently become the focus of research by workers in a variety of disciplines, stimulated by their potential applications to technology ('biomimetics'). This interest, together with the discovery of unpublished electron micrographs taken by the late Dr John Huxley (Natural History Museum, London), prompted this review of butterfly photonics in general. The current work provides a synopsis of the literature to date, covering the diversity and evolution of these optical structures and incorporating Huxley's work, which represents an important biomimetic and evolutionary database on its own. This review deals with butterfly photonic devices according to the parts of the butterfly scales on which they occur. In this way, the information is ripe for evolutionary study.

  13. Letters in Time and Retinotopic Space

    ERIC Educational Resources Information Center

    Adelman, James S.

    2011-01-01

    Various phenomena in tachistoscopic word identification and priming (WRODS and LTRS are confused with and prime WORDS and LETTERS) suggest that position-specific channels are not used in the processing of letters in words. Previous approaches to this issue have sought alternative matching rules because they have assumed that these phenomena reveal…

  14. Letter to, and Paintings by, George Catlin

    ERIC Educational Resources Information Center

    Rosenbaum, David; Potter, Lee Ann; Eder, Elizabeth K.

    2008-01-01

    Letters received and sent by Secretary of War Lewis Cass in the 1830s reveal much about relations between the U.S. government and Native Americans. In the immediate aftermath of the Indian Removal Act, signed into law on May 28, 1830, by President Andrew Jackson, some letters came from interpreters and school teachers seeking payment for their…

  15. 48 CFR 18.112 - Letter contracts.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 1 2014-10-01 2014-10-01 false Letter contracts. 18.112 Section 18.112 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION CONTRACTING METHODS AND CONTRACT TYPES EMERGENCY ACQUISITIONS Available Acquisition Flexibilities 18.112 Letter...

  16. 48 CFR 18.112 - Letter contracts.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 1 2013-10-01 2013-10-01 false Letter contracts. 18.112 Section 18.112 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION CONTRACTING METHODS AND CONTRACT TYPES EMERGENCY ACQUISITIONS Available Acquisition Flexibilities 18.112 Letter...

  17. 48 CFR 18.112 - Letter contracts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Letter contracts. 18.112 Section 18.112 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION CONTRACTING METHODS AND CONTRACT TYPES EMERGENCY ACQUISITIONS Available Acquisition Flexibilities 18.112 Letter...

  18. 48 CFR 18.112 - Letter contracts.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 1 2012-10-01 2012-10-01 false Letter contracts. 18.112 Section 18.112 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION CONTRACTING METHODS AND CONTRACT TYPES EMERGENCY ACQUISITIONS Available Acquisition Flexibilities 18.112 Letter...

  19. 48 CFR 316.603 - Letter contracts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Letter contracts. 316.603 Section 316.603 Federal Acquisition Regulations System HEALTH AND HUMAN SERVICES CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Time-and-Materials, Labor-Hour, and Letter Contracts 316.603...

  20. An Open Letter to Tomorrow's Secondary Teachers

    ERIC Educational Resources Information Center

    Worthy, Jeff

    2016-01-01

    The article takes the form of a letter written to pre-service or beginning teachers at the secondary level in the public school system. The letter acknowledges the attributes they bring to the profession (enthusiasm, optimism, creativity, and open-mindedness) and calls on them to make the most of and work to sustain these traits as they begin…

  1. An Open Letter to Premier Wen Jiabao

    ERIC Educational Resources Information Center

    Chinese Education and Society, 2008

    2008-01-01

    This article is an open letter of a group of early childhood education (ECE) practitioners to Premier Wen Jiabao. This open letter was written with one goal in mind: to ask Premier Wen's government to take measures to protect young children and support early childhood education. These practitioners have become worried about the many accidents that…

  2. 48 CFR 16.603 - Letter contracts.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Letter contracts. 16.603 Section 16.603 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Time-and-Materials, Labor-Hour, and Letter Contracts...

  3. 48 CFR 18.112 - Letter contracts.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Letter contracts. 18.112 Section 18.112 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION CONTRACTING METHODS AND CONTRACT TYPES EMERGENCY ACQUISITIONS Available Acquisition Flexibilities 18.112 Letter...

  4. 49 CFR 107.309 - Warning letters.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 2 2014-10-01 2014-10-01 false Warning letters. 107.309 Section 107.309 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY... Associate Administrator may issue a warning letter to any person whom the Associate Administrator...

  5. 49 CFR 107.309 - Warning letters.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 2 2011-10-01 2011-10-01 false Warning letters. 107.309 Section 107.309 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY... Associate Administrator may issue a warning letter to any person whom the Associate Administrator...

  6. 49 CFR 107.309 - Warning letters.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 2 2013-10-01 2013-10-01 false Warning letters. 107.309 Section 107.309 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY... Associate Administrator may issue a warning letter to any person whom the Associate Administrator...

  7. Essay: the origin of physical review letters.

    PubMed

    Trigg, George L

    2008-11-21

    When Sam Goudsmit, then Editor of Physical Review, decided to publish the Letters separately, he asked me to become Assistant Editor of the new journal. I wound up staying at PRL for a quarter of a century. I describe some of the new techniques we developed to speed up review and production so that Letters could be quickly published.

  8. Cognitive Determinants of Early Letter Knowledge

    ERIC Educational Resources Information Center

    Helal, Suha; Weil-Barais, Annick

    2015-01-01

    The present study investigated the general cognitive determinants of alphabetic letter knowledge. It involved 60 French kindergarten children (mean age: five years six months). Two test batteries were used: the CMS to evaluate general cognitive abilities (memory, attention, and learning), and the LKT to assess letter knowledge and its various…

  9. Linguistic Prescriptivism in Letters to the Editor

    ERIC Educational Resources Information Center

    Lukac, Morana

    2016-01-01

    The public's concern with the fate of the standard language has been well documented in the history of the complaint tradition. The print media have for centuries featured letters to the editor on questions of language use. This study examines a corpus of 258 language-related letters to the editor published in the English-speaking print media. By…

  10. Genre Analysis of Business Letters of Negotiation.

    ERIC Educational Resources Information Center

    dos Santos, V. B. M. Pinto

    2002-01-01

    Reports findings of a survey on genre analysis of 117 commercial letters in English exchanged by fax between a Brazilian company and two European companies. The letters were analyzed in terms of shared communicative purposes and rhetorical features that together contribute to the building-up of the resulting generic structure named "Business…

  11. The Case of the Purloined Letter.

    ERIC Educational Resources Information Center

    Zirkel, Perry A.

    2003-01-01

    Analyzes Arkansas case wherein the Eighth Circuit held 6-5 that letter written by seventh-grade student threatening violence against his former girl friend was not protected by the First Amendment even though a friend took the letter from student's home without his knowledge and gave it to the girl. Upheld board's decision to expel student.…

  12. From Numbers to Letters: Feedback Regularization in Visual Word Recognition

    ERIC Educational Resources Information Center

    Molinaro, Nicola; Dunabeitia, Jon Andoni; Marin-Gutierrez, Alejandro; Carreiras, Manuel

    2010-01-01

    Word reading in alphabetic languages involves letter identification, independently of the format in which these letters are written. This process of letter "regularization" is sensitive to word context, leading to the recognition of a word even when numbers that resemble letters are inserted among other real letters (e.g., M4TERI4L). The present…

  13. Samuel Hartlib on the death of Descartes: a rediscovered letter to Henry More

    PubMed Central

    Penman, Leigh T. I.

    2015-01-01

    This paper discloses the content of a previously overlooked epistle by the Anglo-Prussian intelligencer Samuel Hartlib to Henry More concerning the death of René Descartes. After a discussion situating the letter within the sequence of the More–Hartlib correspondence, an analysis of the rhetorical structure of the epistle is offered, followed by a brief assessment of Hartlib's attitude towards Descartes, and the identification of his source concerning the news of the philosopher's death. An account of the transmission of the letter via a nineteenth-century periodical is also provided. The text of Hartlib's letter and an overlooked passage of Hartlib's diary concerning Descartes's death, which draws on the content of the More letter, are presented as appendixes.

  14. Letter identification and the neural image classifier.

    PubMed

    Watson, Andrew B; Ahumada, Albert J

    2015-02-12

    Letter identification is an important visual task for both practical and theoretical reasons. To extend and test existing models, we have reviewed published data for contrast sensitivity for letter identification as a function of size and have also collected new data. Contrast sensitivity increases rapidly from the acuity limit but slows and asymptotes at a symbol size of about 1 degree. We recast these data in terms of contrast difference energy: the average of the squared distances between the letter images and the average letter image. In terms of sensitivity to contrast difference energy, and thus visual efficiency, there is a peak around ¼ degree, followed by a marked decline at larger sizes. These results are explained by a Neural Image Classifier model that includes optical filtering and retinal neural filtering, sampling, and noise, followed by an optimal classifier. As letters are enlarged, sensitivity declines because of the increasing size and spacing of the midget retinal ganglion cell receptive fields in the periphery.

  15. Evolutionary theory in letters to the editor.

    PubMed

    Silva, Eric Orion; Lowe, Clayton Cory

    2015-05-01

    This research note presents the results of a content analysis of 234 letters to the editors that discuss evolutionary theory and were published in American newspapers. We find that letters to the editor both support and hinder the cause of teaching evolutionary theory in American secondary schools. On the one hand, anti-evolutionary theory messages are marginalized in the letters section. This marginalization signals a low level of legitimacy for creationism. It might also contribute to the sense of tension that sustains creationist identities. On the other hand, relatively few letters explicitly note the fact that scientists or the scientific community accept evolution. Interestingly, the obscuration of the scientific community's support for evolutionary theory occurs both in letters supporting and opposing evolutionary theory.

  16. Medicines in the correspondence of the Mozart family.

    PubMed

    Nieznanowska, J

    2001-12-01

    The most famous members of the Mozart family were musicians - not physicians. In spite of that, the family correspondence of the Mozarts contains much noteworthy information on 18th century medicine. It comes mainly from Leopold, the famous composer's father, which is why the vast majority of the medical data presented in the letters cannot be found in the popular editions of the correspondence. One of the medicine-related subjects usually omitted or presented briefly in such editions concerns the medicaments used in the Mozart family. Out of more than 100 remedies mentioned in the correspondence the article's author chose and described a few that seem to have played a particularly significant role in the life of the Mozart family.

  17. Letters from Ainsworth: Contesting the ‘Organization’ of Attachment

    PubMed Central

    Landa, Sophie; Duschinsky, Robbie

    2013-01-01

    As Main (1999) noted in her obituary for Mary Ainsworth, ‘she was interacting weekly by letter and manuscript with her mentor and friend, John Bowlby, and their academic correspondence formed an important part of her, and implicitly our, life.’ These letters of Ainsworth to John Bowlby during the 1980s, available in the Wellcome Trust Library in London, contain valuable reflections on the work of her pupils to extend her system of classifying infant behaviour in the Strange Situation Procedure. Mary Main proposed a D classification and interpreted such behaviour as a breakdown in an ABC strategy caused by a conflict between a disposition to approach and flee from the caregiver. Patricia Crittenden extended the subtypes of A and C, using a developmental model of information processing, and observed that they could be used together in A/C combinations. These letters offer insight into Ainsworth’s intellectual rationale for encouraging both Main and Crittenden in their conflicting endeavours. PMID:23667365

  18. Search for letter identity and location by disabled readers.

    PubMed

    Enns, J T; Bryson, S E; Roes, C

    1995-09-01

    Reading-disabled boys, reading- and age-matched controls, and adults searched letter arrays for the identity or location of a probe letter. Response time (RT) and accuracy were examined as a function of the temporal relation between probe and array letters (probe first, simultaneous, array first), and array size (1-5 letters). Although disabled readers closely resembled age controls in RT, their accuracy differed significantly when large letter arrays were tested. In the letter identification task, this was only evident when the array letters preceded the probe; in the letter location task, it occurred in all three probe conditions. Correlational analyses showed that all subjects were influenced by the visual, but not the phonological, similarity between letters. Thus, a reading-related impairment is evident in both letter identification and letter location processes, even when the phonological coding of letters has been minimized.

  19. Optimal time scales of input fluctuations for spiking coherence and reliability in stochastic Hodgkin-Huxley neurons

    NASA Astrophysics Data System (ADS)

    Guo, Xinmeng; Wang, Jiang; Liu, Jing; Yu, Haitao; Galán, Roberto F.; Cao, Yibin; Deng, Bin

    2017-02-01

    Channel noise, which is generated by the random transitions of ion channels between open and closed states, is distinguished from external sources of physiological variability such as spontaneous synaptic release and stimulus fluctuations. This inherent stochasticity in ion-channel current can lead to variability of the timing of spikes occurring both spontaneously and in response to stimuli. In this paper, we investigate how intrinsic channel noise affects the response of stochastic Hodgkin-Huxley (HH) neuron to external fluctuating inputs with different amplitudes and correlation time. It is found that there is an optimal correlation time of input fluctuations for the maximal spiking coherence, where the input current has a fluctuating rate approximately matching the inherent oscillation of stochastic HH model and plays a dominating role in the timing of spike firing. We also show that the reliability of spike timing in the model is very sensitive to the properties of the current input. An optimal time scale of input fluctuations exists to induce the most reliable firing. The channel-noise-induced unreliability can be mostly overridden by injecting a fluctuating current with an appropriate correlation time. The spiking coherence and reliability can also be regulated by the size of channel stochasticity. As the membrane area (or total channel number) of the neuron increases, the spiking coherence decreases but the spiking reliability increases.

  20. Pregnancy as protest in interwar British women's writing: an antecedent alternative to Aldous Huxley's Brave New World.

    PubMed

    Bigman, Fran

    2016-12-01

    Accounts that take Aldous Huxley's Brave New World (1932) as representative of interwar reproductive dystopia fail to recognise that the novel expresses both an interest and an anxiety about the possibility of new reproductive technologies to transform sex, gender, and the family that were widely shared by writers in different genres and perhaps expressed best by those likely to be most affected: women. This article explores three earlier works-Charlotte Haldane's Man's World (1926), Vera Brittain's Halcyon, or the Future of Monogamy (1929), and Naomi Mitchison's Comments on Birth Control (1930)-in which pregnancy, instead of figuring as illness or debility, becomes a form of resistance to the status quo. These works engage with biomedicine, however, rather than abjuring it. Through a reading of these works, this article argues that the intersection of medical humanities and science fiction (SF) can enrich both: medical humanities can push SF to go beyond the canon, and SF can challenge any characterisation of literature in the medical humanities as purely fantastical by demonstrating how it responds to the hopes and anxieties of a particular time.

  1. Teaching and learning the Hodgkin-Huxley model based on software developed in NEURON’s programming language hoc

    PubMed Central

    2013-01-01

    Background We present a software tool called SENB, which allows the geometric and biophysical neuronal properties in a simple computational model of a Hodgkin-Huxley (HH) axon to be changed. The aim of this work is to develop a didactic and easy-to-use computational tool in the NEURON simulation environment, which allows graphical visualization of both the passive and active conduction parameters and the geometric characteristics of a cylindrical axon with HH properties. Results The SENB software offers several advantages for teaching and learning electrophysiology. First, SENB offers ease and flexibility in determining the number of stimuli. Second, SENB allows immediate and simultaneous visualization, in the same window and time frame, of the evolution of the electrophysiological variables. Third, SENB calculates parameters such as time and space constants, stimuli frequency, cellular area and volume, sodium and potassium equilibrium potentials, and propagation velocity of the action potentials. Furthermore, it allows the user to see all this information immediately in the main window. Finally, with just one click SENB can save an image of the main window as evidence. Conclusions The SENB software is didactic and versatile, and can be used to improve and facilitate the teaching and learning of the underlying mechanisms in the electrical activity of an axon using the biophysical properties of the squid giant axon. PMID:23675833

  2. Membrane Capacitive Memory Alters Spiking in Neurons Described by the Fractional-Order Hodgkin-Huxley Model

    PubMed Central

    Weinberg, Seth H.

    2015-01-01

    Excitable cells and cell membranes are often modeled by the simple yet elegant parallel resistor-capacitor circuit. However, studies have shown that the passive properties of membranes may be more appropriately modeled with a non-ideal capacitor, in which the current-voltage relationship is given by a fractional-order derivative. Fractional-order membrane potential dynamics introduce capacitive memory effects, i.e., dynamics are influenced by a weighted sum of the membrane potential prior history. However, it is not clear to what extent fractional-order dynamics may alter the properties of active excitable cells. In this study, we investigate the spiking properties of the neuronal membrane patch, nerve axon, and neural networks described by the fractional-order Hodgkin-Huxley neuron model. We find that in the membrane patch model, as fractional-order decreases, i.e., a greater influence of membrane potential memory, peak sodium and potassium currents are altered, and spike frequency and amplitude are generally reduced. In the nerve axon, the velocity of spike propagation increases as fractional-order decreases, while in a neural network, electrical activity is more likely to cease for smaller fractional-order. Importantly, we demonstrate that the modulation of the peak ionic currents that occurs for reduced fractional-order alone fails to reproduce many of the key alterations in spiking properties, suggesting that membrane capacitive memory and fractional-order membrane potential dynamics are important and necessary to reproduce neuronal electrical activity. PMID:25970534

  3. Numerical simulations of piecewise deterministic Markov processes with an application to the stochastic Hodgkin-Huxley model.

    PubMed

    Ding, Shaojie; Qian, Min; Qian, Hong; Zhang, Xuejuan

    2016-12-28

    The stochastic Hodgkin-Huxley model is one of the best-known examples of piecewise deterministic Markov processes (PDMPs), in which the electrical potential across a cell membrane, V(t), is coupled with a mesoscopic Markov jump process representing the stochastic opening and closing of ion channels embedded in the membrane. The rates of the channel kinetics, in turn, are voltage-dependent. Due to this interdependence, an accurate and efficient sampling of the time evolution of the hybrid stochastic systems has been challenging. The current exact simulation methods require solving a voltage-dependent hitting time problem for multiple path-dependent intensity functions with random thresholds. This paper proposes a simulation algorithm that approximates an alternative representation of the exact solution by fitting the log-survival function of the inter-jump dwell time, H(t), with a piecewise linear one. The latter uses interpolation points that are chosen according to the time evolution of the H(t), as the numerical solution to the coupled ordinary differential equations of V(t) and H(t). This computational method can be applied to all PDMPs. Pathwise convergence of the approximated sample trajectories to the exact solution is proven, and error estimates are provided. Comparison with a previous algorithm that is based on piecewise constant approximation is also presented.

  4. Derivation of Hodgkin-Huxley equations for a Na+ channel from a master equation for coupled activation and inactivation

    NASA Astrophysics Data System (ADS)

    Vaccaro, S. R.

    2016-11-01

    The Na+ current in nerve and muscle membranes may be described in terms of the activation variable m (t ) and the inactivation variable h (t ) , which are dependent on the transitions of S4 sensors of each of the Na+ channel domains DI to DIV. The time-dependence of the Na+ current and the rate equations satisfied by m (t ) and h (t ) may be derived from the solution to a master equation that describes the coupling between two or three activation sensors regulating the Na+ channel conductance and a two-stage inactivation process. If the inactivation rate from the closed or open states increases as the S4 sensors activate, a more general form of the Hodgkin-Huxley expression for the open-state probability may be derived where m (t ) is dependent on both activation and inactivation processes. The voltage dependence of the rate functions for inactivation and recovery from inactivation are consistent with the empirically determined expressions and exhibit saturation for both depolarized and hyperpolarized clamp potentials.

  5. Effects of information transmission delay and channel blocking on synchronization in scale-free Hodgkin-Huxley neuronal networks

    NASA Astrophysics Data System (ADS)

    Wang, Qing-Yun; Zheng, Yan-Hong

    2011-12-01

    In this paper, we investigate the evolution of spatiotemporal patterns and synchronization transitions in dependence on the information transmission delay and ion channel blocking in scale-free neuronal networks. As the underlying model of neuronal dynamics, we use the Hodgkin-Huxley equations incorporating channel blocking and intrinsic noise. It is shown that delays play a significant yet subtle role in shaping the dynamics of neuronal networks. In particular, regions of irregular and regular propagating excitatory fronts related to the synchronization transitions appear intermittently as the delay increases. Moreover, the fraction of working sodium and potassium ion channels can also have a significant impact on the spatiotemporal dynamics of neuronal networks. As the fraction of blocked sodium channels increases, the frequency of excitatory events decreases, which in turn manifests as an increase in the neuronal synchrony that, however, is dysfunctional due to the virtual absence of large-amplitude excitations. Expectedly, we also show that larger coupling strengths improve synchronization irrespective of the information transmission delay and channel blocking. The presented results are also robust against the variation of the network size, thus providing insights that could facilitate understanding of the joint impact of ion channel blocking and information transmission delay on the spatiotemporal dynamics of neuronal networks.

  6. Hodgkin-Huxley analysis of whole-cell outward rectifying K(+)-currents in protoplasts from tobacco cell suspension cultures.

    PubMed

    Van Duijn, B

    1993-02-01

    The voltage and time dependence of outward-rectifying K+ currents (IK,out) measured in protoplasts from tobacco cell suspension cultures in the whole-cell configuration of the patch-clamp technique are quantitatively analyzed. The voltage and time dependence was described according to the Hodgkin and Huxley model for IK,out currents in the squid giant axon, and to allow comparison, in analogy with the quantitative analysis of IK,out currents in Vicia faba guard cell protoplasts as described by Schroeder (J. Membrane Biol., 107:229-235, 1989). The IK,out from tobacco could be described by a similar model as the IK,out from guard cell protoplasts (i.e., sigmoid activation time course, activation variable raised to second power, single exponential deactivating tail currents, absence of inactivation). However, in contrast to guard cells, both the activation and deactivation time constants were strongly voltage dependent in tobacco protoplasts. The voltage dependence of the transition rates for channel opening and channel closing was slightly asymmetrical and inverse to the asymmetry found in guard cells. The data presented show that the voltage-dependent kinetic properties of the IK,out conductance of tobacco protoplasts are different from these properties in guard cell protoplasts. This analysis provides a basis for the study of IK,out conductance function and modulation.

  7. A single order-disorder transition generates tension during the Huxley-Simmons phase 2 in muscle.

    PubMed Central

    Davis, J S; Harrington, W F

    1993-01-01

    Increasing temperature was used to progressively interconvert non-force-generating into force-generating states in skinned rabbit psoas muscle fibers contracting isometrically. Laser temperature-jump and length-jump experiments were used to characterize tension generation in the time domain of the Huxley-Simmons phase 2. In our experiments, phase 2 is subdivisible into two kinetic steps each with quite different physical properties. The fast kinetic component has rate constant of 950 s-1 at 1 degrees C and a Q10 of approximately 1.2. Its rate is tension insensitive and its normalized amplitude declines with rising temperature--behavior that closely parallels the instantaneous stiffness of the cross-bridge. It is likely that this kinetic step is a manifestation of a damped elastic element/s in the fiber. The slow component of phase 2 is temperature-dependent with a Q10 of approximately 3.0. Its rate is sensitive to tension. Unlike the fast component, its amplitude remains in fixed proportion to isometric tension at different temperatures indicating direct participation in tension generation. Similar T-jump studies on frog fibers are also included. The combined results (frog and rabbit) suggest that tension generation occurs in a single endothermic (entropy driven) step in phase 2. PMID:8298018

  8. Optimal size of stochastic Hodgkin-Huxley neuronal systems for maximal energy efficiency in coding pulse signals.

    PubMed

    Yu, Lianchun; Liu, Liwei

    2014-03-01

    The generation and conduction of action potentials (APs) represents a fundamental means of communication in the nervous system and is a metabolically expensive process. In this paper, we investigate the energy efficiency of neural systems in transferring pulse signals with APs. By analytically solving a bistable neuron model that mimics the AP generation with a particle crossing the barrier of a double well, we find the optimal number of ion channels that maximizes the energy efficiency of a neuron. We also investigate the energy efficiency of a neuron population in which the input pulse signals are represented with synchronized spikes and read out with a downstream coincidence detector neuron. We find an optimal number of neurons in neuron population, as well as the number of ion channels in each neuron that maximizes the energy efficiency. The energy efficiency also depends on the characters of the input signals, e.g., the pulse strength and the interpulse intervals. These results are confirmed by computer simulation of the stochastic Hodgkin-Huxley model with a detailed description of the ion channel random gating. We argue that the tradeoff between signal transmission reliability and energy cost may influence the size of the neural systems when energy use is constrained.

  9. Membrane capacitive memory alters spiking in neurons described by the fractional-order Hodgkin-Huxley model.

    PubMed

    Weinberg, Seth H

    2015-01-01

    Excitable cells and cell membranes are often modeled by the simple yet elegant parallel resistor-capacitor circuit. However, studies have shown that the passive properties of membranes may be more appropriately modeled with a non-ideal capacitor, in which the current-voltage relationship is given by a fractional-order derivative. Fractional-order membrane potential dynamics introduce capacitive memory effects, i.e., dynamics are influenced by a weighted sum of the membrane potential prior history. However, it is not clear to what extent fractional-order dynamics may alter the properties of active excitable cells. In this study, we investigate the spiking properties of the neuronal membrane patch, nerve axon, and neural networks described by the fractional-order Hodgkin-Huxley neuron model. We find that in the membrane patch model, as fractional-order decreases, i.e., a greater influence of membrane potential memory, peak sodium and potassium currents are altered, and spike frequency and amplitude are generally reduced. In the nerve axon, the velocity of spike propagation increases as fractional-order decreases, while in a neural network, electrical activity is more likely to cease for smaller fractional-order. Importantly, we demonstrate that the modulation of the peak ionic currents that occurs for reduced fractional-order alone fails to reproduce many of the key alterations in spiking properties, suggesting that membrane capacitive memory and fractional-order membrane potential dynamics are important and necessary to reproduce neuronal electrical activity.

  10. Statistical mechanics of letters in words

    NASA Astrophysics Data System (ADS)

    Stephens, Greg J.; Bialek, William

    2010-06-01

    We consider words as a network of interacting letters, and approximate the probability distribution of states taken on by this network. Despite the intuition that the rules of English spelling are highly combinatorial and arbitrary, we find that maximum entropy models consistent with pairwise correlations among letters provide a surprisingly good approximation to the full statistics of words, capturing ˜92% of the multi-information in four-letter words and even “discovering” words that were not represented in the data. These maximum entropy models incorporate letter interactions through a set of pairwise potentials and thus define an energy landscape on the space of possible words. Guided by the large letter redundancy we seek a lower-dimensional encoding of the letter distribution and show that distinctions between local minima in the landscape account for ˜68% of the four-letter entropy. We suggest that these states provide an effective vocabulary which is matched to the frequency of word use and much smaller than the full lexicon.

  11. Statistical mechanics of letters in words.

    PubMed

    Stephens, Greg J; Bialek, William

    2010-06-01

    We consider words as a network of interacting letters, and approximate the probability distribution of states taken on by this network. Despite the intuition that the rules of English spelling are highly combinatorial and arbitrary, we find that maximum entropy models consistent with pairwise correlations among letters provide a surprisingly good approximation to the full statistics of words, capturing ∼92% of the multi-information in four-letter words and even "discovering" words that were not represented in the data. These maximum entropy models incorporate letter interactions through a set of pairwise potentials and thus define an energy landscape on the space of possible words. Guided by the large letter redundancy we seek a lower-dimensional encoding of the letter distribution and show that distinctions between local minima in the landscape account for ∼68% of the four-letter entropy. We suggest that these states provide an effective vocabulary which is matched to the frequency of word use and much smaller than the full lexicon.

  12. [The professor and his student. The correspondence between Lorenz Heister and Christoph Jacob Trew].

    PubMed

    Ruisinger, Marion Maria; Schnalke, Thomas

    2004-01-01

    Letters were the central medium of communication in the medical scientific community of the 18th century. Professional as well as personal relationships were established among the various correspondents. These relationships constituted the smallest units of communication which contributed to the regional and international scientific network of the Republic of Letters. A correspondence that grew out of a trusted teacher-student relationship could gain an especially intense character both intellectually and personally. This contribution offers an analysis of an example of just such a correspondence. Lorenz Heister (1683--1758), medical professor at the universities of Altdorf and Helmstedt, and his disciple, Christoph Jacob Trew (1695--1769), who became a renowned physician and natural scientist in Nuremberg, communicated in letters to one another over a span of almost forty years. Their correspondence started as a rather asymmetrical dialogue. Over time, however, Heister and Trew came to meet as equals in almost every field of their competence. Their letters reveal a broad spectrum of scientific, organisational, professional, medical and personal issues which formed the basis of a stable and lasting learned correspondence in the age of Enlightenment.

  13. EDITORIAL: Letter from the Editor Letter from the Editor

    NASA Astrophysics Data System (ADS)

    Pashinin, Pavel P.

    2013-01-01

    Dear readers, contributors, and members of the world laser physics community. It is a great honour for us to introduce to you our new publishing partner, IOP Publishing, a subsidiary of the Institute of Physics, United Kingdom. IOP Publishing is a world renowned authority in producing journals, magazines, websites and services that enable researchers and research organizations to present their work to a world-wide audience. Laser Physics, the first English-language scientific journal in Russia, was founded in 1990 on the initiative of Alexander M Prokhorov, a pioneer and leader in laser physics research. Professor Prokhorov served as the first Editor-in-Chief of the journal until 2002. We are proud that it is our 23rd year of publishing Laser Physics and our 10th year of publishing Laser Physics Letters. We would like to honour the memory of our friend, late Professor Igor Yevseyev, whose enthusiasm and unwavering dedication to our journals contributed most significantly to their success. It was initially his idea in 2011 to approach IOP with a partnership proposal. We deeply regret that he is no longer with us as we enter this productive alliance. Now, in partnership with IOP, we are turning a new page in providing world-wide access to the cutting-edge research results in our journals, serving our well established global audience. We see new horizons opening for our journals for years to come and hope that our readers share our enthusiasm and aspirations. Please accept our best wishes for all your new scientific endeavors in the exciting field of laser physics.

  14. Quantum key distribution with multi letter alphabets

    NASA Astrophysics Data System (ADS)

    Sych, D.; Leuchs, G.

    2010-03-01

    We present a new protocol for continuous variable quantum key distribution (CV QKD). The novelty of the protocol is a multi letter alphabet represented by coherent states of light with a fixed amplitude and variable phase. Information is encoded in the phase of a coherent state which can be chosen from a regular discrete set consisting, however, of an arbitrary number of letters. We evaluate the security of the protocol against the beam splitting attack. As a result we show the proposed protocol has advantages over the standard two letter coherent state QKD protocol, especially in the case when losses in the communication channel are low.

  15. 15 CFR 908.13 - Address of letters.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... SUBMITTING REPORTS ON WEATHER MODIFICATION ACTIVITIES § 908.13 Address of letters. Letters and other communications intended for the Administrator, in connection with weather modification reporting or...

  16. Quantum Painleve-Calogero correspondence

    SciTech Connect

    Zabrodin, A.; Zotov, A.

    2012-07-15

    The Painleve-Calogero correspondence is extended to auxiliary linear problems associated with Painleve equations. The linear problems are represented in a new form which has a suggestive interpretation as a 'quantized' version of the Painleve-Calogero correspondence. Namely, the linear problem responsible for the time evolution is brought into the form of non-stationary Schroedinger equation in imaginary time, {partial_derivative}{sub t}{psi}=((1/2) {partial_derivative}{sub x}{sup 2}+V(x,t)){psi}, whose Hamiltonian is a natural quantization of the classical Calogero-like Hamiltonian H=(1/2) p{sup 2}+V(x,t) for the corresponding Painleve equation. In present paper, we present explicit constructions for the first five equations from the Painleve list.

  17. Attitudes to abortion in the era of reform: evidence from the Abortion Law Reform Association correspondence.

    PubMed

    Jones, Emma L

    2011-01-01

    This article examines letters sent by members of the general public to the Abortion Law Reform Association (ALRA) in the decade immediately before the 1967 Abortion Act. It shows how a voluntary organisation, in their aim of supporting a specific cause of unclear legality, called forth correspondence from those in need. In detailing the personal predicaments of those facing an unwanted pregnancy, this body of correspondence was readily deployed by ALRA in their efforts to mobilise support for abortion law reform, thus exercising a political function. A close examination of the content of the letters and the epistolary strategies adopted by their writers reveals that as much as they were a lobbying tool for changes in abortion law, these letters were discursively shaped by debates surrounding that very reform.

  18. Letter to Dr. Felix Bronner

    NASA Technical Reports Server (NTRS)

    Greenleaf, John E.; Dalton, Bonnie (Technical Monitor)

    2002-01-01

    Dear Dr. Bronner: I have been reading in The Physiologist the letters from senior physiologists for many years with great interest. It is impressive that many of the respondents are still pursuing scientific endeavours in their 70's and some even in their 80's. The interesting task is to ponder the relative causative proportions of heredity and environment responsible. One wonders whether knowing something about physiology engenders longer and more productive lives? I suspect so because of the accompanying self-discipline. But another factor would seem to be the pervasive joy of working in this profession. I have been fortunate to be able to acquire the joy of physiology during my graduate studies at Illinois, and to have been able to carry it over here at NASA, Ames Research Center for the past 40 years. A truly academic style research environment at a federal research center is rare. The trick to a joyous research career is to overcome those ever-present slings and arrows of outrageous fortune with dignity whenever possible. To that end I have found solace and guidance in reading the history of warfare and its leaders, especially Sun Tsu's The Art of War and Clauswitz's On War. I became eligible for retirement in 1993, but to insure domestic tranquility and also the joy of pursuing my research hobby have continued working in the laboratory on human research. It is troubling to see that funding for individual scientists conducting human research is declining rapidly, along with their new ideas; perhaps the old ones are more comfortable. Hopefully I can provide a similar response when I'm 80! Thanks for your interest. Sincerely, John Greenleaf

  19. A letter from Janet Benshoof.

    PubMed

    Benshoof, J

    1997-06-06

    This letter to readers of "Reproductive Freedom News" criticizes the American Medical Association's (AMA) Board of Trustees for endorsing a bill in the US Senate that would ban "partial-birth" abortions and allow the imprisonment of physicians who perform the procedure. The decision of the Board of Trustees was made in total disregard to the AMA bylaws, because the decision ran counter to the recommendations of an AMA task force that concluded that the AMA should take no action on this bill but seek to preserve the ability of physicians to use their discretion in providing medical care and the viability line in abortion legislation. The proposed criminal ban fails to contain a viability line; provides no exception to protect a woman's health, medical choice, or safety; and provides no exception in cases of fetal anomaly. The action by the Board of Trustees seriously undermines the work of the Center for Reproductive Law and Policy and gives abortion opponents ammunition to mount a serious challenge to the Roe vs. Wade decision. The AMA endorsement goes beyond simply stating that the procedure should never be used; it endorses giving physicians who perform such abortions, for whatever reason, prison terms. This position undermines two critical principles long upheld by the AMA: 1) that physicians must be able to carry out their medical responsibilities free from government interference and 2) that women have a fundamental right to decide on the appropriate provision of abortion services within their physician-patient relationship. The damage from this endorsement can and should be undone by the AMA's House of Delegates at their meeting in June 1997.

  20. 2006 Children's Health Protection Advisory Committee Letters

    EPA Pesticide Factsheets

    These letters to and from Administrator Stephen Johnson are regarding risks from polybrominated biphenyl ethers (PBEs), the Voluntary Children's Chemical Evaluation Project, perchlorate PRG and water contamination, and NAAQS for particulate matter.

  1. 2007 Children's Health Protection Advisory Committee Letters

    EPA Pesticide Factsheets

    These letters to and from Administrator Stephen Johnson are regarding mutagenic mode of action, carcinogenicity, NAAQS for ozone, evaluating existing and new chemicals, research translation, and NAAQS for lead.

  2. Gender bias found in recommendation letters

    NASA Astrophysics Data System (ADS)

    Kruesi, Liz

    2016-11-01

    Female postdoctoral fellowship applicants are half as likely as their male counterparts to receive glowing recommendation letters, according to a study by researchers at Columbia University's Lamont-Doherty Earth Observatory (LDEO).

  3. A Letter to Gabriela, A Young Writer.

    ERIC Educational Resources Information Center

    Mora, Pat

    1990-01-01

    Presents a letter written by a professional writer (and a former high school and college teacher) to a young female student who has started writing poems. Discusses why and how she writes. Urges the student to continue writing. (RS)

  4. Resource Letter ETC-1: extraterrestrial civilization.

    PubMed

    Kuiper, T B; Brin, G D

    1989-01-01

    This Resource Letter provides a guide to the literature about intelligent life beyond the human sphere of exploration. It offers a starting point for professionals and academics interested in participating in the debate about the existence of other technological civilizations or in the search for extraterrestrial intelligence (SETI). It can also serve as a reference for teaching. This Letter is not intended as an exhaustive bibliography, but several extensive bibliographies have been cited. The letter E after an item indicates elementary, nontechnical material of general interest to persons becoming informed in the field. Intermediate level material, of a somewhat more specialized nature, is indicated by the Letter I. The annotation A indicates advanced, technical material. An asterisk (*) precedes items to be included in an accompanying Reprint Book.

  5. Relative Width and Height of Handwritten Letter.

    PubMed

    Lizega Rika, Joseba

    2017-02-28

    This is an exploratory study that analyzes the width and the height of letters in two texts written by each of the 21 writers analyzed. After detrending the linear, text, and allograph trends, we proceeded to comparing the sizes obtained in different texts. The different detrended series were compared by means of correlation and t-test. According to the results regarding the width of letters, the texts of 19 of 21 writers correlated strongly, whereas the texts of two writers did not correlate with the limits of the threshold. With regard to the height of letters, texts written by between 18 and 21 writers of 21 writers correlated strongly, whereas texts that did not correlate were within the threshold value. Regarding both the width and the height of letters, of 21 writers, texts written by between 19 and 21 individuals were found to correlate strongly.

  6. Fogger and Mister Final Signed Letter

    EPA Pesticide Factsheets

    EPA has asked pesticide companies to provide data or amend registrations of products claiming to control public health microorganisms when applied by fogging and/or misting methods. The letter further describes the ways in which the company may respond.

  7. 49 CFR 190.205 - Warning letters.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY PIPELINE SAFETY PROGRAMS AND RULEMAKING..., OPS, may issue a Warning Letter notifying the owner or operator of the probable violation and...

  8. 49 CFR 190.205 - Warning letters.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY PIPELINE SAFETY PROGRAMS AND RULEMAKING..., OPS, may issue a Warning Letter notifying the owner or operator of the probable violation and...

  9. 49 CFR 190.205 - Warning letters.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY PIPELINE SAFETY PROGRAMS AND RULEMAKING..., OPS, may issue a Warning Letter notifying the owner or operator of the probable violation and...

  10. Scientists' Letter Supports Climate Change Panel

    NASA Astrophysics Data System (ADS)

    Chell, Kaitlin

    2010-03-01

    Recent media coverage about climate change has focused on errors in the 2007 Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4) and other concerns. In light of this media coverage, an open letter sent on 12 March to members of the U.S. Congress and various U.S. federal agencies in support of the IPCC has been signed (at Eos press time) by more than 250 U.S. scientists. The letter lays out the IPCC process and also examines climate science findings since the publication of AR4. “Our goal with this letter is to demonstrate the strong support that exists within the scientific community for the IPCC and its main findings,” Gary Yohe of Wesleyan University noted in a press release issued about the letter.

  11. 2004 Children's Health Protection Advisory Committee Letters

    EPA Pesticide Factsheets

    Most of these letters are to Administrator Leavitt, regarding school environments, risks due to polybrominated diphenyl ethers (PBDEs), mercury emissions, fish advisory, cancer susceptibility, pollution from power plants, and the National Children's Study.

  12. 2010 Children's Health Protection Advisory Committee Letters

    EPA Pesticide Factsheets

    Letters to and from Administrator Jackson, also including a report from CHPAC's school siting task group, address school siting guidelines issues as well as response to a National Research Council (NRC) report on risk assessment.

  13. 2012 Children's Health Protection Advisory Committee Letters

    EPA Pesticide Factsheets

    These two letters address National Ambient Air Quality Standards proposed for particulate matter (PM), and childhood lead poisoning prevention particularly as regards revision of the Integrated Exposure Uptake Biokinetic model.

  14. 2005 Children's Health Protection Advisory Committee Letters

    EPA Pesticide Factsheets

    These letters, mainly to and from Administrators Stephen Johnson, regard the Clean Air Mercury Rule, Particulate Matter National Ambient Air Quality Standards, cancer susceptibility, fish consumption advisories, human subjects, hurricanes, and pesticides.

  15. Blue Ribbon Panel Report Cover Letter

    Cancer.gov

    The letter from NCI Acting Director Douglas R. Lowy, M.D., to Vice President Biden that accompanied the Blue Ribbon Panel final report, thanking the Vice President for his commitment to and leadership of the Cancer Moonshot.

  16. The Traps of Formal Correspondence.

    ERIC Educational Resources Information Center

    Albert, Sandor

    The dangers of translation are discussed when the translator does not try to create textual equivalence, but settles for formal correspondence (i.e., with simple transcoding at a linguistic level) during the process of translating. Difficulties of explaining, commenting, or summarizing rather than translating are also discussed. Pedagogical and…

  17. National Security Management Correspondence Course.

    ERIC Educational Resources Information Center

    Industrial Coll. of the Armed Forces (DOD), Washington, DC.

    A course of study on the fundamental aspects of the areas of knowledge which are essential to effective management of national security is presented. The course presents the substance of the Industrial College resident curriculum adapted to the correspondence method of study. The subject matter is designed to impart knowledge and understanding of…

  18. Morphology and spelling in French students with dyslexia: the case of silent final letters.

    PubMed

    Quémart, Pauline; Casalis, Séverine

    2017-04-01

    Spelling is a challenge for individuals with dyslexia. Phoneme-to-grapheme correspondence rules are highly inconsistent in French, which make them very difficult to master, in particular for dyslexics. One recurrent manifestation of this inconsistency is the presence of silent letters at the end of words. Many of these silent letters perform a morphological function. The current study examined whether students with dyslexia (aged between 10 and 15 years) benefit from the morphological status of silent final letters when spelling. We compared, their ability to spell words with silent final letters that are either morphologically justified (e.g., tricot, "knit," where the final "t" is pronounced in morphologically related words such as tricoter, "to knit" and tricoteur "knitter") or not morphologically justified (e.g., effort, "effort") to that of a group of younger children matched for reading and spelling level. Results indicated that the dyslexic students' spelling of silent final letters was impaired in comparison to the control group. Interestingly, morphological status helped the dyslexics improve the accuracy of their choice of final letters, contrary to the control group. This finding provides new evidence of morphological processing in dyslexia during spelling.

  19. The Development of a Noncontact Letter Input Interface “Fingual” Using Magnetic Dataset

    NASA Astrophysics Data System (ADS)

    Fukushima, Taishi; Miyazaki, Fumio; Nishikawa, Atsushi

    We have newly developed a noncontact letter input interface called “Fingual”. Fingual uses a glove mounted with inexpensive and small magnetic sensors. Using the glove, users can input letters to form the finger alphabets, a kind of sign language. The proposed method uses some dataset which consists of magnetic field and the corresponding letter information. In this paper, we show two recognition methods using the dataset. First method uses Euclidean norm, and second one additionally uses Gaussian function as a weighting function. Then we conducted verification experiments for the recognition rate of each method in two situations. One of the situations is that subjects used their own dataset; the other is that they used another person's dataset. As a result, the proposed method could recognize letters with a high rate in both situations, even though it is better to use their own dataset than to use another person's dataset. Though Fingual needs to collect magnetic dataset for each letter in advance, its feature is the ability to recognize letters without the complicated calculations such as inverse problems. This paper shows results of the recognition experiments, and shows the utility of the proposed system “Fingual”.

  20. 76 FR 37094 - List of Correspondence

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-24

    ... May Be of Interest to Readers Topic Addressed: Harassment And Bullying. Dear Colleague Letter dated October 26, 2010 from Office for Civil Rights Assistant Secretary Russlynn Ali, regarding bullying...

  1. Resource Letter SW1: Space Weather

    NASA Astrophysics Data System (ADS)

    Baker, Daniel N.; Lanzerotti, Louis J.

    2016-03-01

    This Resource Letter describes the phenomena and effects on technological systems that are known collectively as space weather. A brief history of the topic is provided, and the scientific understandings of drivers for such phenomena are discussed. The impacts of space disturbances are summarized, and the strategies for dealing with space weather threats are examined. The Resource Letter concludes with description of approaches that have been proposed to deal with threats to our increasingly technological society.

  2. Letter to the Editor: Robert W. Evans

    NASA Astrophysics Data System (ADS)

    Johnston, A.

    2000-12-01

    I read the Letters page of the latest issue of the JBAA (2000 October) with some amusement. My very good friend Bob Evans had, according to the letter header, not only been elevated to the clergy, but had also transferred his nationality from Kiwi to Aussie. While he'll probably overlook the religious error he may not be so sanguine about being mistaken for an Australian.

  3. The challenges of editorship: a reflection on editing the Jung-Neumann correspondence.

    PubMed

    Liebscher, Martin

    2016-04-01

    The complete correspondence between C.G. Jung and Erich Neumann was published in 2015. This article attempts to provide insight into the practical task, as well as the theoretical background, of the editing process. The advantages and possibilities of an unabridged edition with an extensive historical contextualization are demonstrated, and compared to the approach of the editors of the Jung Letters and their selection therein of Jung's letters to Neumann. The practical points under consideration include the establishment of the letter corpus, the ascertainment of dates and the chronological arrangement of the letter exchange, as well as the deciphering of handwritten letters. Theoretical aspects under discussion involve the question of the merits of a critical contextualisation and the position of the editor vis-à-vis the research object. The example of the selecting and editing of Jung's letters to Neumann by Aniela Jaffé and Gerhard Adler reveals how drastically the close ties of those editors with Jung, Neumann, and members of the Zurich analytical circles compromised their editorial work at times. The advantage for an editor being able to work from an historical distance is appreciated.

  4. EFL Students' Preferences toward the Lecturer's Corrective Feedback in Business Letters Writing

    ERIC Educational Resources Information Center

    Sanu, La Ode

    2016-01-01

    This study aimed to investigate the students' preferences toward the lecturer's corrective feedback in the business letter writing and their reasons why they preferred particular corrective feedback types. A case study was used by involving 15 EFL students who enrolled in the Business Correspondence Course. The questionnaire and interview were…

  5. "Why Downt You Riyt Back to Me?": Family Letter Writing in Kindergarten

    ERIC Educational Resources Information Center

    Pole, Kathryn

    2015-01-01

    This article presents research that investigated how a school year-long letter-writing project between kindergarten students and extended family members could facilitate literacy development in students, as well as provide a way to build inter-generational bonds through correspondence focused on family history and stories. Analysis centered on the…

  6. Large Auditory and Small Visual Effects in the Recall of Consonant Letters

    ERIC Educational Resources Information Center

    Locke, John L.

    1978-01-01

    Eighty-six adults serially recalled lists of visually presented consonant letters similar in auditory or visual features or dissimilar on both feature sets. There were significantly more errors at every auditory list position than at the corresponding visual and neutral list positions, which did not themselves differ. Positive correlation exists…

  7. On the Functional Neuroanatomy of Visual Word Processing: Effects of Case and Letter Deviance

    ERIC Educational Resources Information Center

    Kronbichler, Martin; Klackl, Johannes; Richlan, Fabio; Schurz, Matthias; Staffen, Wolfgang; Ladurner, Gunther; Wimmer, Heinz

    2009-01-01

    This functional magnetic resonance imaging study contrasted case-deviant and letter-deviant forms with familiar forms of the same phonological words (e.g., "TaXi" and "Taksi" vs. "Taxi") and found that both types of deviance led to increased activation in a left occipito-temporal region, corresponding to the visual word form area (VWFA). The…

  8. Assessing the influence of letter position in reading normal and transposed texts using a letter detection task.

    PubMed

    Guérard, Katherine; Saint-Aubin, Jean; Poirier, Marie; Demetriou, Constantina

    2012-12-01

    During word recognition, some letters appear to play a more important role than others. Although some studies have suggested that the first and last letters of a word have a privileged status, there is no consensus with regards to the importance of the different letter positions when reading connected text. In the current experiments, we used a simple letter search task to examine the impact of letter position on word identification in connected text using a classic paper and pencil procedure (Experiment 1) and an eye movement monitoring procedure (Experiment 2). In Experiments 3 and 4, a condition with transposed letters was included. Our results show that the first letter of a word is detected more easily than the other letters, and transposing letters in a word revealed the importance of the final letter. It is concluded that both the initial and final letters play a special role in word identification during reading but that the underlying processes might differ.

  9. Mean-field description and propagation of chaos in networks of Hodgkin-Huxley and FitzHugh-Nagumo neurons.

    PubMed

    Baladron, Javier; Fasoli, Diego; Faugeras, Olivier; Touboul, Jonathan

    2012-05-31

    We derive the mean-field equations arising as the limit of a network of interacting spiking neurons, as the number of neurons goes to infinity. The neurons belong to a fixed number of populations and are represented either by the Hodgkin-Huxley model or by one of its simplified version, the FitzHugh-Nagumo model. The synapses between neurons are either electrical or chemical. The network is assumed to be fully connected. The maximum conductances vary randomly. Under the condition that all neurons' initial conditions are drawn independently from the same law that depends only on the population they belong to, we prove that a propagation of chaos phenomenon takes place, namely that in the mean-field limit, any finite number of neurons become independent and, within each population, have the same probability distribution. This probability distribution is a solution of a set of implicit equations, either nonlinear stochastic differential equations resembling the McKean-Vlasov equations or non-local partial differential equations resembling the McKean-Vlasov-Fokker-Planck equations. We prove the well-posedness of the McKean-Vlasov equations, i.e. the existence and uniqueness of a solution. We also show the results of some numerical experiments that indicate that the mean-field equations are a good representation of the mean activity of a finite size network, even for modest sizes. These experiments also indicate that the McKean-Vlasov-Fokker-Planck equations may be a good way to understand the mean-field dynamics through, e.g. a bifurcation analysis.Mathematics Subject Classification (2000): 60F99, 60B10, 92B20, 82C32, 82C80, 35Q80.

  10. Mean-field description and propagation of chaos in networks of Hodgkin-Huxley and FitzHugh-Nagumo neurons

    PubMed Central

    2012-01-01

    We derive the mean-field equations arising as the limit of a network of interacting spiking neurons, as the number of neurons goes to infinity. The neurons belong to a fixed number of populations and are represented either by the Hodgkin-Huxley model or by one of its simplified version, the FitzHugh-Nagumo model. The synapses between neurons are either electrical or chemical. The network is assumed to be fully connected. The maximum conductances vary randomly. Under the condition that all neurons’ initial conditions are drawn independently from the same law that depends only on the population they belong to, we prove that a propagation of chaos phenomenon takes place, namely that in the mean-field limit, any finite number of neurons become independent and, within each population, have the same probability distribution. This probability distribution is a solution of a set of implicit equations, either nonlinear stochastic differential equations resembling the McKean-Vlasov equations or non-local partial differential equations resembling the McKean-Vlasov-Fokker-Planck equations. We prove the well-posedness of the McKean-Vlasov equations, i.e. the existence and uniqueness of a solution. We also show the results of some numerical experiments that indicate that the mean-field equations are a good representation of the mean activity of a finite size network, even for modest sizes. These experiments also indicate that the McKean-Vlasov-Fokker-Planck equations may be a good way to understand the mean-field dynamics through, e.g. a bifurcation analysis. Mathematics Subject Classification (2000): 60F99, 60B10, 92B20, 82C32, 82C80, 35Q80. PMID:22657695

  11. Letter Position Dyslexia in Arabic: From Form to Position

    PubMed Central

    Friedmann, Naama; Haddad-Hanna, Manar

    2012-01-01

    This study reports the reading of 11 Arabic-speaking individuals with letter position dyslexia (LPD), and the effect of letter form on their reading errors. LPD is a peripheral dyslexia caused by a selective deficit to letter position encoding in the orthographic-visual analyzer, which results in migration of letters within words, primarily of middle letters. The Arabic orthography is especially interesting for the study of LPD because Arabic letters have different forms in different positions in the word. As a result, some letter position errors require letter form change. We compared the rate of letter migrations that change letter form with migrations that do not change letter form in 10 Arabic-speaking individuals with developmental LPD, and one bilingual Arabic and Hebrew-speaking individual with acquired LPD. The results indicated that the participants made 40% letter position errors in migratable words when the resulting word included the letters in the same form, whereas migrations that changed letter form almost never occurred. The error rate of the Arabic-Hebrew bilingual reader was smaller in Arabic than in Hebrew. However, when only words in which migrations do not change letter form were counted, the rate was similar in Arabic and Hebrew. Hence, whereas orthographies with multiple letter forms for each letter might seem more difficult in some respects, these orthographies are in fact easier to read in some forms of dyslexia. Thus, the diagnosis of LPD in Arabic should consider the effect of letter forms on migration errors, and use only migratable words that do not require letter-form change. The theoretical implications for the reading model are that letter form (of the position-dependent type found in Arabic) is part of the information encoded in the abstract letter identity, and thus affects further word recognition processes, and that there might be a pre-lexical graphemic buffer in which the checking of orthographic well-formedness takes place

  12. Using Letters to Support Consultative Work in Schools

    ERIC Educational Resources Information Center

    Bozic, Nick

    2004-01-01

    This paper reports how consultative work with teachers can be supported by the use of letters. Letters were written by an educational psychologist (EP) after a consultation meeting with a teacher. Features of therapeutic letter writing and solution-focused brief therapy were used to increase the collaborative intent of the letters. Follow-up…

  13. 33 CFR 127.009 - Letter of recommendation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Letter of recommendation. 127.009... General § 127.009 Letter of recommendation. (a) After the COTP receives the Letter of Intent under § 127.007(a) or (b), the COTP issues a Letter of Recommendation (LOR) as to the suitability of the...

  14. Representation of Letter Position in Spelling: Evidence from Acquired Dysgraphia

    ERIC Educational Resources Information Center

    Fischer-Baum, Simon; McCloskey, Michael; Rapp, Brenda

    2010-01-01

    The graphemic representations that underlie spelling performance must encode not only the identities of the letters in a word, but also the positions of the letters. This study investigates how letter position information is represented. We present evidence from two dysgraphic individuals, CM and LSS, who perseverate letters when spelling: that…

  15. 19 CFR 177.9 - Effect of ruling letters.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 19 Customs Duties 2 2012-04-01 2012-04-01 false Effect of ruling letters. 177.9 Section 177.9... TREASURY (CONTINUED) ADMINISTRATIVE RULINGS General Ruling Procedure § 177.9 Effect of ruling letters. (a) Effect of ruling letters generally. A ruling letter issued by the Customs Service under the provisions...

  16. 48 CFR 1602.170-10 - Letter of credit.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 6 2013-10-01 2013-10-01 false Letter of credit. 1602.170... Terms 1602.170-10 Letter of credit. Letter of credit means the method by which certain carriers, and... available. For each carrier participating in the letter of credit arrangement for payment under this...

  17. 12 CFR 337.2 - Standby letters of credit.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 5 2013-01-01 2013-01-01 false Standby letters of credit. 337.2 Section 337.2... UNSAFE AND UNSOUND BANKING PRACTICES § 337.2 Standby letters of credit. (a) Definition. As used in this section, the term standby letter of credit means any letter of credit, or similar arrangement...

  18. 12 CFR 337.2 - Standby letters of credit.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 4 2010-01-01 2010-01-01 false Standby letters of credit. 337.2 Section 337.2... UNSAFE AND UNSOUND BANKING PRACTICES § 337.2 Standby letters of credit. (a) Definition. As used in this section, the term standby letter of credit means any letter of credit, or similar arrangement...

  19. Letter Writing: A Great Way to Explore Whole Language.

    ERIC Educational Resources Information Center

    Flack, Jerry

    1995-01-01

    Discusses the importance of using letter writing to promote whole-language learning. Suggests ideas and actions, and provides examples of children's literature that uses the letter format, to weave letters and letter writing into the whole-language curriculum. (BAC)

  20. Neural Correlates of Top-Down Letter Processing

    ERIC Educational Resources Information Center

    Liu, Jiangang; Li, Jun; Zhang, Hongchuan; Rieth, Cory A.; Huber, David E.; Li, Wu; Lee, Kang; Tian, Jie

    2010-01-01

    This fMRI study investigated top-down letter processing with an illusory letter detection task. Participants responded whether one of a number of different possible letters was present in a very noisy image. After initial training that became increasingly difficult, they continued to detect letters even though the images consisted of pure noise,…

  1. 19 CFR 177.9 - Effect of ruling letters.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 2 2010-04-01 2010-04-01 false Effect of ruling letters. 177.9 Section 177.9... TREASURY (CONTINUED) ADMINISTRATIVE RULINGS General Ruling Procedure § 177.9 Effect of ruling letters. (a) Effect of ruling letters generally. A ruling letter issued by the Customs Service under the provisions...

  2. A Phase-Locking Analysis of Neuronal Firing Rhythms with Transcranial Magneto-Acoustical Stimulation Based on the Hodgkin-Huxley Neuron Model

    PubMed Central

    Yuan, Yi; Pang, Na; Chen, Yudong; Wang, Yi; Li, Xiaoli

    2017-01-01

    Transcranial magneto-acoustical stimulation (TMAS) uses ultrasonic waves and a static magnetic field to generate electric current in nerve tissues for the purpose of modulating neuronal activities. It has the advantage of high spatial resolution and penetration depth. Neuronal firing rhythms carry and transmit nerve information in neural systems. In this study, we investigated the phase-locking characteristics of neuronal firing rhythms with TMAS based on the Hodgkin-Huxley neuron model. The simulation results indicate that the modulation frequency of ultrasound can affect the phase-locking behaviors. The results of this study may help us to explain the potential firing mechanism of TMAS. PMID:28163679

  3. Letter from President Millard Fillmore to the Emperor of Japan: The President's Letter Opened a Closed Country to the West

    ERIC Educational Resources Information Center

    Pinkert, Marvin; Potter, Lee Ann

    2004-01-01

    In 1852, Commodore Matthew C. Perry of the U.S. Navy sailed to Japan with instructions to deliver a letter from President Millard Fillmore to the Emperor. The letter eventually led to the 1854 Treaty of Kanagawa and the opening of Japan to trade with Western nations. The State Department's letter book copy of the letter is featured in this…

  4. Letter-Transposition Effects Are Not Universal: The Impact of Transposing Letters in Hebrew

    ERIC Educational Resources Information Center

    Velan, Hadas; Frost, Ram

    2009-01-01

    We examined the effects of letter-transposition in Hebrew in three masked-priming experiments. Hebrew, like English has an alphabetic orthography where sequential and contiguous letter strings represent phonemes. However, being a Semitic language it has a non-concatenated morphology that is based on root derivations. Experiment 1 showed that…

  5. ERP Correlates of Letter Identity and Letter Position Are Modulated by Lexical Frequency

    ERIC Educational Resources Information Center

    Vergara-Martinez, Marta; Perea, Manuel; Gomez, Pablo; Swaab, Tamara Y.

    2013-01-01

    The encoding of letter position is a key aspect in all recently proposed models of visual-word recognition. We analyzed the impact of lexical frequency on letter position assignment by examining the temporal dynamics of lexical activation induced by pseudowords extracted from words of different frequencies. For each word (e.g., BRIDGE), we created…

  6. Automatic letters with Microsoft Word for Windows.

    PubMed

    Gerraty, B J

    1996-03-01

    This article offers a simple process for creating a series of separate letter formats and then automating the production of individual letters from them. These letter formats can then be assembled into various categories and displayed on a computer screen. The key concepts are: Templates, Fields, Auto Macros, Macros and Custom Dialog Boxes. This is made possible because Word for Windows allows the exploration and alteration of its basic editing commands. It has great flexibility as nothing is set in concrete: a built-in command macro may be changed and a custom macro created to replace it. This article assumes the use of Microsoft Word 6.0 and some familiarity with it. The various macros notated are 'syntax sensitive' so a full stop or comma in the wrong place, or left out, will result in the macro failing to run.

  7. Mindfulness reduces the correspondence bias.

    PubMed

    Hopthrow, Tim; Hooper, Nic; Mahmood, Lynsey; Meier, Brian P; Weger, Ulrich

    2017-03-01

    The correspondence bias (CB) refers to the idea that people sometimes give undue weight to dispositional rather than situational factors when explaining behaviours and attitudes. Three experiments examined whether mindfulness, a non-judgmental focus on the present moment, could reduce the CB. Participants engaged in a brief mindfulness exercise (the raisin task), a control task, or an attention to detail task before completing a typical CB measure involving an attitude-attribution paradigm. The results indicated that participants in the mindfulness condition experienced a significant reduction in the CB compared to participants in the control or attention to detail conditions. These results suggest that mindfulness training can play a unique role in reducing social biases related to person perception.

  8. On the Theorem of Correspondence.

    PubMed

    Krøjgaard, Peter

    2017-03-01

    In a recent paper, Mammen (Integrative Psychological and Behavioral Science, 50, 196-233, 2016a) brought novel arguments into the discussion concerning the importance of being able to single out and track objects through space and time. Mammen offered a formal account of two basic, yet distinct, ways in which we as human beings encounter objects in the real world, that is, sense and choice categories. In this paper I discuss aspects of his theory and in particular the Theorem of Correspondence. I shall attempt to argue that Mammen's formal account is indeed a novel and powerful analytical generic tool allowing us to see the important relevance in different domains of being able to establish choice categories. Meanwhile, I will attempt to show that evidence from the so-called multiple object tracking studies -- even though these use highly artificial stimuli -- provide compelling evidence in support of Mammen's formal account.

  9. A Retrospective Analysis Comparing the New Standardized Letter of Recommendation in Dermatology with the Classic Narrative Letter of Recommendation.

    PubMed

    Kaffenberger, Jessica A; Mosser, Joy; Lee, Grace; Pootrakul, Llana; Harfmann, Katya; Fabbro, Stephanie; Faith, Esteban Fernandez; Carr, David; Plotner, Alisha; Zirwas, Matthew; Kaffenberger, Benjamin H

    2016-09-01

    Background: In an effort to avoid numerous problems associated with narrative letters of recommendation, a dermatology standardized letter of recommendation was utilized in the 2014-2015 resident application cycle. Objective: A comparison of the standardized letter of recommendation and narrative letters of recommendation from a single institution and application cycle to determine if the standardized letter of recommendation met its original goals of efficiency, applicant stratification, and validity. Methods: Eight dermatologists assessed all standardized letters of recommendation/narrative letters of recommendation pairs received during the 2014-2015 application cycle. Five readers repeated the analysis two months later. Each letter of recommendation was evaluated based on a seven question survey. Letter analysis and survey completion for each letter was timed. Results: Compared to the narrative letters of recommendation, the standardized letter of recommendation is easier to interpret (p<0.0001), has less exaggeration of applicants' positive traits (p<0.001), and has higher inter-rater and intrarater reliability for determining applicant traits including personality, reliability, work-ethic, and global score. Standardized letters of recommendation are also faster to interpret (p<0.0001) and provide more information about the writer's background or writer-applicant relationship than narrative letters of recommendation (p<0.001). Limitations: This study was completed at a single institution. Conclusions: The standardized letter of recommendation appears to be meeting its initial goals of 1) efficiency, 2) applicant stratification, and 3) validity. (J Clin Aesthet Dermatol. 2016;9(9):36-2.).

  10. [Structured electronic consultation letter for shoulder disorders].

    PubMed

    Paloneva, Juha; Oikari, Marjo; Ylinen, Jari; Ingalsuo, Minna; Ilkka, Kunnamo; Ilkka, Kiviranta

    2012-01-01

    Referral to a specialist has a significant influence on management of the patient and costs associated with the treatments. However, development and research of the process by which patients are referred has been almost neglected. Expectations considering the purpose, contents, and timing of the referral of the consulting physician and the consultant do not always meet. A structured, electronic consultation letter was developed to respond this need. Functionality and interactivity are the key elements of the referral, including (1) an electronic referral letter to a specialist, (2) interactive education in clinical examination and management of shoulder disorders, and (3) an instrument of clinical examination and documentation of shoulder disorders.

  11. Representation of Letter Position in Spelling: Evidence from Acquired Dysgraphia

    PubMed Central

    Fischer-Baum, Simon; McCloskey, Michael; Rapp, Brenda

    2010-01-01

    The graphemic representations that underlie spelling performance must encode not only the identities of the letters in a word, but also the positions of the letters. This study investigates how letter position information is represented. We present evidence from two dysgraphic individuals, CM and LSS, who perseverate letters when spelling: that is, letters from previous spelling responses intrude into subsequent responses. The perseverated letters appear more often than expected by chance in the same position in the previous and subsequent responses. We used these errors to address the question of how letter position is represented in spelling. In a series of analyses we determined how often the perseveration errors produced maintain position as defined by a number of alternative theories of letter position encoding proposed in the literature. The analyses provide strong evidence that the grapheme representations used in spelling encode letter position such that position is represented in a graded manner based on distance from both edges of the word. PMID:20378104

  12. A look at the Salomé-Freud correspondence.

    PubMed

    Sirois, F

    1998-04-01

    The author notes that the changing emphasis of the correspondence between Lou Andreas-Salomé and Sigmund Freud over the years reflects certain aspects of the development of every analyst. Her contributions are shown to illustrate the evolution of the analyst's relationship with theory and the growth of his or her clinical capacity and involvement. Two phases in the analyst's clinical progression are stated to be discernible in the correspondence, marked by changes of direction that mirror the changing nature of her relationship with Freud. Theoretical considerations predominate in the first phase, while clinical aspects gradually come to the fore in the second. Freud is seen to be offering Salomé a kind of supervision by letter. Lou's underlying transference to Freud also emerges from the correspondence, its two aspects being the relationship to a big brother and to a father respectively. Freud's complementary transference to Salomé is also discussed, partly in connection with her relationship with his daughter Anna. The author's arguments are supported by extensive quotations from the correspondence, biographical works and Lou Andreas-Salomé's published diaries and reminiscences. Last but not least, her relationship with Freud in the author's view indirectly raises the issue of that of any analyst to the founder of psychoanalysis.

  13. Letters in the forest: global precedence effect disappears for letters but not for non-letters under reading-like conditions

    PubMed Central

    Lachmann, Thomas; Schmitt, Andreas; Braet, Wouter; van Leeuwen, Cees

    2014-01-01

    Normally skilled reading involves special processing strategies for letters, which are habitually funneled into an abstract letter code. On the basis of previous studies we argue that this habit leads to the preferred usage of an analytic strategy for the processing of letters, while non-letters are preferably processed via a holistic strategy. The well-known global precedence effect (GPE) seems to contradict to this assumption, since, with compound, hierarchical figures, including letter items, faster responses are observed to the global than to the local level of the figure, as well as an asymmetric interference effect from global to local level. We argue that with letters these effects depend on presentation conditions; only when they elicit the processing strategies automatized for reading, an analytic strategy for letters in contrast to non-letters is to be expected. We compared the GPE for letters and non-letters in central viewing, with the global stimulus size close to the functional visual field in whole word reading (6.5° of visual angle) and local stimuli close to the critical size for fluent reading of individual letters (0.5° of visual angle). Under these conditions, the GPE remained robust for non-letters. For letters, however, it disappeared: letters showed no overall response time advantage for the global level and symmetric congruence effects (local-to-global as well as global-to-local interference). We interpret these results as according to the view that reading is based on resident analytic visual processing strategies for letters. PMID:25101012

  14. Letters in the forest: global precedence effect disappears for letters but not for non-letters under reading-like conditions.

    PubMed

    Lachmann, Thomas; Schmitt, Andreas; Braet, Wouter; van Leeuwen, Cees

    2014-01-01

    Normally skilled reading involves special processing strategies for letters, which are habitually funneled into an abstract letter code. On the basis of previous studies we argue that this habit leads to the preferred usage of an analytic strategy for the processing of letters, while non-letters are preferably processed via a holistic strategy. The well-known global precedence effect (GPE) seems to contradict to this assumption, since, with compound, hierarchical figures, including letter items, faster responses are observed to the global than to the local level of the figure, as well as an asymmetric interference effect from global to local level. We argue that with letters these effects depend on presentation conditions; only when they elicit the processing strategies automatized for reading, an analytic strategy for letters in contrast to non-letters is to be expected. We compared the GPE for letters and non-letters in central viewing, with the global stimulus size close to the functional visual field in whole word reading (6.5° of visual angle) and local stimuli close to the critical size for fluent reading of individual letters (0.5° of visual angle). Under these conditions, the GPE remained robust for non-letters. For letters, however, it disappeared: letters showed no overall response time advantage for the global level and symmetric congruence effects (local-to-global as well as global-to-local interference). We interpret these results as according to the view that reading is based on resident analytic visual processing strategies for letters.

  15. Cross-sensory correspondences and symbolism in spoken and written language.

    PubMed

    Walker, Peter

    2016-09-01

    Lexical sound symbolism in language appears to exploit the feature associations embedded in cross-sensory correspondences. For example, words incorporating relatively high acoustic frequencies (i.e., front/close rather than back/open vowels) are deemed more appropriate as names for concepts associated with brightness, lightness in weight, sharpness, smallness, speed, and thinness, because higher pitched sounds appear to have these cross-sensory features. Correspondences also support prosodic sound symbolism. For example, speakers might raise the fundamental frequency of their voice to emphasize the smallness of the concept they are naming. The conceptual nature of correspondences and their functional bidirectionality indicate they should also support other types of symbolism, including a visual equivalent of prosodic sound symbolism. For example, the correspondence between auditory pitch and visual thinness predicts that a typeface with relatively thin letter strokes will reinforce a word's reference to a relatively high pitch sound (e.g., squeal). An initial rating study confirms that the thinness-thickness of a typeface's letter strokes accesses the same cross-sensory correspondences observed elsewhere. A series of speeded word classification experiments then confirms that the thinness-thickness of letter strokes can facilitate a reader's comprehension of the pitch of a sound named by a word (thinner letter strokes being appropriate for higher pitch sounds), as can the brightness of the text (e.g., white-on-gray text being appropriate for the names of higher pitch sounds). It is proposed that the elementary visual features of text are represented in the same conceptual system as word meaning, allowing cross-sensory correspondences to support visual symbolism in language. (PsycINFO Database Record

  16. Creating Colored Letters: Familial Markers of Grapheme-Color Synesthesia in Parietal Lobe Activation and Structure.

    PubMed

    Colizoli, Olympia; Murre, Jaap M J; Scholte, H Steven; Rouw, Romke

    2017-02-14

    Perception is inherently subjective, and individual differences in phenomenology are well illustrated by the phenomenon of synesthesia (highly specific, consistent, and automatic cross-modal experiences, in which the external stimulus corresponding to the additional sensation is absent). It is unknown why some people develop synesthesia and others do not. In the current study, we tested whether neural markers related to having synesthesia in the family were evident in brain function and structure. Relatives of synesthetes (who did not have any type of synesthesia themselves) and matched controls read specially prepared books with colored letters for several weeks and were scanned before and after reading using magnetic resonance imaging. Effects of acquired letter-color associations were evident in brain activation. Training-related activation (while viewing black letters) in the right angular gyrus of the parietal lobe was directly related to the strength of the learned letter-color associations (behavioral Stroop effect). Within this obtained angular gyrus ROI, the familial trait of synesthesia related to brain activation differences while participants viewed both black and colored letters. Finally, we compared brain structure using voxel-based morphometry and diffusion tensor imaging to test for group differences and training effects. One cluster in the left superior parietal lobe had significantly more coherent white matter in the relatives compared with controls. No evidence for experience-dependent plasticity was obtained. For the first time, we present evidence suggesting that the (nonsynesthete) relatives of grapheme-color synesthetes show atypical grapheme processing as well as increased brain connectivity.

  17. Introduction to Literary Criticism: "The Scarlet Letter."

    ERIC Educational Resources Information Center

    Lawrence, Lisa

    This course seeks to provide high school students the opportunity to sharpen their critical thinking skills and use of language through acquaintance with some ideas of literary criticism. The course features Nathaniel Hawthorne's "The Scarlet Letter," assuming that the students have just finished reading that American classic novel. The…

  18. Elevation Withdrawal Letter - signed March 27, 2003

    EPA Pesticide Factsheets

    A letter regarding a recent decision to issue a Clean Water Act Section 404 permit to the Virginia Seafood Council for the trial placement of one million non-native oysters into waters of the Chesapeake Bay and the Atlantic Ocean.

  19. Letters of a Slave Turned Union Soldier.

    ERIC Educational Resources Information Center

    Humanities, 1990

    1990-01-01

    Discusses the influx of Black soldiers into the Union army following the Emancipation Proclamation. Concentrates on the case of Private Spotswood Rice. Provides a short history of Rice, including copies of Rice's letters to his enslaved daughters, the daughter's slaveholders, and an angry retort from the slaveowner to the federal commander in…

  20. Letters from Roger: Exercises in Communication.

    ERIC Educational Resources Information Center

    Campbell, Russell N.; Bracy, Maryruth

    This book is designed for low-intermediate to advanced students of English as a second language. It provides a look at the world that awaits the foreign student who is to be suddenly immersed in an English-speaking society. The format involves a number of letters written by an American university student to a foreign student planning a trip to the…

  1. Resource Letter CF-1: Casimir Force

    SciTech Connect

    Lamoreaux, S.K.

    1999-10-01

    This resource letter provides an introductory guide to the literature on the Casimir force. Journal articles and books are cited for the following topics: introductory articles and books, calculations, dynamical Casimir effect, mechanical analogs, applications, and experiments. {copyright} {ital 1999 American Association of Physics Teachers.}

  2. 19 CFR 356.16 - Charging letter.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 3 2011-04-01 2011-04-01 false Charging letter. 356.16 Section 356.16 Customs Duties INTERNATIONAL TRADE ADMINISTRATION, DEPARTMENT OF COMMERCE PROCEDURES AND RULES FOR IMPLEMENTING ARTICLE 1904 OF THE NORTH AMERICAN FREE TRADE AGREEMENT Violation of a Protective Order or a...

  3. 19 CFR 356.16 - Charging letter.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 19 Customs Duties 3 2013-04-01 2013-04-01 false Charging letter. 356.16 Section 356.16 Customs Duties INTERNATIONAL TRADE ADMINISTRATION, DEPARTMENT OF COMMERCE PROCEDURES AND RULES FOR IMPLEMENTING ARTICLE 1904 OF THE NORTH AMERICAN FREE TRADE AGREEMENT Violation of a Protective Order or a...

  4. 19 CFR 356.16 - Charging letter.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 3 2010-04-01 2010-04-01 false Charging letter. 356.16 Section 356.16 Customs Duties INTERNATIONAL TRADE ADMINISTRATION, DEPARTMENT OF COMMERCE PROCEDURES AND RULES FOR IMPLEMENTING ARTICLE 1904 OF THE NORTH AMERICAN FREE TRADE AGREEMENT Violation of a Protective Order or a...

  5. Samuel Beckett: Color, Letter, and Line.

    ERIC Educational Resources Information Center

    Conley, Tom

    1985-01-01

    Through a bilingual reading of Beckett's "Mal vu mal dit," the illusion of painted relief for printed letters is created. Colors manifest themselves through the continual process of translation. The French translation adds color to the black and white English text. (DF)

  6. 42 CFR 93.202 - Charge letter.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Charge letter. 93.202 Section 93.202 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES HEALTH ASSESSMENTS AND HEALTH EFFECTS STUDIES OF HAZARDOUS SUBSTANCES RELEASES AND FACILITIES PUBLIC HEALTH SERVICE POLICIES ON...

  7. "Physical Review Letters" in the Classroom

    ERIC Educational Resources Information Center

    Angiolillo, Paul J.; Lynch, Jonathan

    2010-01-01

    Ask any physicist what the preeminent journal in the field is, and I think the almost unanimous answer will be "Physical Review Letters" ("PRL"). This weekly journal of the American Physical Society publishes high-impact research from all the major subdisciplines of physics. This journal is not the one you would think is the first place a high…

  8. Employer Preferences for Resumes and Cover Letters

    ERIC Educational Resources Information Center

    Schullery, Nancy M.; Ickes, Linda; Schullery, Stephen E.

    2009-01-01

    This article reports the results of a survey of employers' preferences for resume style, resume delivery method, and cover letters. Employers still widely prefer the standard chronological resume, with only 3% desiring a scannable resume. The vast majority of employers prefer electronic delivery, either by email (46%) or at the company's Web site…

  9. 19 CFR 207.103 - Charging letter.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 19 Customs Duties 3 2013-04-01 2013-04-01 false Charging letter. 207.103 Section 207.103 Customs Duties UNITED STATES INTERNATIONAL TRADE COMMISSION NONADJUDICATIVE INVESTIGATIONS INVESTIGATIONS OF WHETHER INJURY TO DOMESTIC INDUSTRIES RESULTS FROM IMPORTS SOLD AT LESS THAN FAIR VALUE OR FROM...

  10. 19 CFR 207.103 - Charging letter.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 3 2011-04-01 2011-04-01 false Charging letter. 207.103 Section 207.103 Customs Duties UNITED STATES INTERNATIONAL TRADE COMMISSION NONADJUDICATIVE INVESTIGATIONS INVESTIGATIONS OF WHETHER INJURY TO DOMESTIC INDUSTRIES RESULTS FROM IMPORTS SOLD AT LESS THAN FAIR VALUE OR FROM...

  11. 19 CFR 207.103 - Charging letter.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 19 Customs Duties 3 2012-04-01 2012-04-01 false Charging letter. 207.103 Section 207.103 Customs Duties UNITED STATES INTERNATIONAL TRADE COMMISSION NONADJUDICATIVE INVESTIGATIONS INVESTIGATIONS OF WHETHER INJURY TO DOMESTIC INDUSTRIES RESULTS FROM IMPORTS SOLD AT LESS THAN FAIR VALUE OR FROM...

  12. 19 CFR 207.103 - Charging letter.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 3 2010-04-01 2010-04-01 false Charging letter. 207.103 Section 207.103 Customs Duties UNITED STATES INTERNATIONAL TRADE COMMISSION NONADJUDICATIVE INVESTIGATIONS INVESTIGATIONS OF WHETHER INJURY TO DOMESTIC INDUSTRIES RESULTS FROM IMPORTS SOLD AT LESS THAN FAIR VALUE OR FROM...

  13. 19 CFR 207.103 - Charging letter.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 19 Customs Duties 3 2014-04-01 2014-04-01 false Charging letter. 207.103 Section 207.103 Customs Duties UNITED STATES INTERNATIONAL TRADE COMMISSION NONADJUDICATIVE INVESTIGATIONS INVESTIGATIONS OF WHETHER INJURY TO DOMESTIC INDUSTRIES RESULTS FROM IMPORTS SOLD AT LESS THAN FAIR VALUE OR FROM...

  14. Crowding Affects Letters and Symbols Differently

    ERIC Educational Resources Information Center

    Grainger, Jonathan; Tydgat, Ilse; Issele, Joanna

    2010-01-01

    Five experiments examined crowding effects with letter and symbol stimuli. Experiments 1 through 3 compared 2-alternative forced-choice (2AFC) identification accuracy for isolated targets presented left and right of fixation with targets flanked either by 2 other items of the same category or a single item situated to the right or left of targets.…

  15. Suspending Damage: A Letter to Communities

    ERIC Educational Resources Information Center

    Tuck, Eve

    2009-01-01

    In this open letter, Eve Tuck calls on communities, researchers, and educators to reconsider the long-term impact of "damage-centered" research--research that intends to document peoples' pain and brokenness to hold those in power accountable for their oppression. This kind of research operates with a flawed theory of change: it is often used to…

  16. Dear Teachers: Letters to Another Hero.

    ERIC Educational Resources Information Center

    Voices from the Middle, 2001

    2001-01-01

    Presents 54 thank you letters written by authors (of children's literature, young adult literature, and professional texts) to classroom teachers, from the shadow of the events of September 11th, 2001, offering their thanks for teachers' efforts to face those events with children, offering their personal thoughts about the events, or their…

  17. Suggestopaedia-Canada. Information Letter, No. 4.

    ERIC Educational Resources Information Center

    Racle, Gabriel

    This issue of the information letter consists of two articles, "Music Therapy" and "Research and Applications of Psychomusical Techniques"; a review of the book, "La musicotherapie et les methods nouvelles d'association des techniques" by Guilhot and Cecourt, and a bibliography of books on music therapy written in…

  18. Resource letter ETC-1 - Extraterrestrial civilization

    NASA Technical Reports Server (NTRS)

    Kuiper, Thomas B. H.; Brin, Glen David

    1989-01-01

    This resource letter provides a guide to the literature about intelligent life beyond the human sphere of exploration. It offers a starting point for professionals and academics interested in participating in the debate about the existence of other technological civilizations or in SETI. It can also serve as a reference for teaching. Several extensive bibliographies are cited.

  19. Writing Recommendation Letters--Without the Stress

    ERIC Educational Resources Information Center

    Toglia, Thomas V.

    2004-01-01

    Sooner or later, every educator hears the following plea from a current or former student: "Will you write a letter of recommendation for me?" Usually, the student is seeking employment or applying to a college or university for additional education. Many times instructors--taken off guard and unprepared for these requests--find themselves staring…

  20. Readerly and Writerly "Letters from the Park."

    ERIC Educational Resources Information Center

    Conde, Susana

    1993-01-01

    Discusses in depth the film "Cartas del parque" ("Letters from the Park"), the first of six films in the "Amores Dificiles" series. Notes that the film is pervaded by the traditional overdetermination of gender roles. Suggests that an intrusive and authoritative narrator makes of this both a "readerly" and a…

  1. Correspondence principle in cochlear mechanics.

    PubMed

    de Boer, E

    1982-06-01

    When only long waves play the most important part in the cochlea, the response can be described by a most simplified model, the one-dimensional model. When short waves are to be included, a more complex model is needed. The response then depends on the dimensionality of the model and is much harder to obtain. This applies especially to the region in the neighborhood of the point where the basilar membrane shows resonance. Both two- and three-dimensional models have been studied to assess the effects of short and long waves. The relative importance of the part played by short waves depends on the damping constant (or loss factor )delta associated with the resonance of the basilar membrane (BM). For very small delta a three-dimensional model is really necessary, it cannot be replaced by a model of lower dimensionality. When delta is small, but not too small, the three-dimensional model can be made equivalent to a two-dimensional one, provided the latter is modified ina specific manner. This paper shows why this is so and which conditions have to be met. The two-dimensional model must undergo two modifications to effect this equivalence. The first modification ensures that the model has the same long-wave behavior. In the second place, a specific additional mass ("added mass") reactance should be added to Z(kappa). An expression for the limiting value of delta, above which this correspondence is valid, is given in the paper. A second, larger, limit is presented as well: when delta is above this limit, the responses of both the three-dimensional and the two-dimensional model are equivalent to that of an appropriately chosen one-dimensional model. In this case too, long-wave behavior must be matched and an "added mass" reactance must be included in Z(kappa). This holds true for the entire cochlea including the region of resonance. For both types of transition the amount of "added mass" is given.

  2. LETTER TO THE EDITOR: No sliding in time

    NASA Astrophysics Data System (ADS)

    Shtengel, Kirill; Nayak, Chetan; Bishara, Waheb; Chamon, Claudio

    2005-09-01

    In this letter, we analyse the following apparent paradox: as has been recently proved by Hastings (2004 Phys. Rev. 69 104431), under a general set of conditions, if a local Hamiltonian has a spectral gap above its (unique) ground state (GS), all connected equal-time correlation functions of local operators decay exponentially with distance. On the other hand, statistical mechanics provides us with examples of 3D models displaying so-called sliding phases (O'Hern et al 1999 Phys. Rev. Lett. 83 2745) which are characterized by the algebraic decay of correlations within 2D layers and exponential decay in the third direction. Interpreting this third direction as time would imply a gap in the corresponding (2+1)D quantum Hamiltonian which would seemingly contradict Hastings' theorem. The resolution of this paradox lies in the non-locality of such a quantum Hamiltonian.

  3. 28 CFR 540.14 - General correspondence.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 28 Judicial Administration 2 2012-07-01 2012-07-01 false General correspondence. 540.14 Section... CONTACT WITH PERSONS IN THE COMMUNITY Correspondence § 540.14 General correspondence. (a) Institution staff shall open and inspect all incoming general correspondence. Incoming general correspondence may...

  4. 28 CFR 540.14 - General correspondence.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 28 Judicial Administration 2 2014-07-01 2014-07-01 false General correspondence. 540.14 Section... CONTACT WITH PERSONS IN THE COMMUNITY Correspondence § 540.14 General correspondence. (a) Institution staff shall open and inspect all incoming general correspondence. Incoming general correspondence may...

  5. 50 CFR 216.257 - Letters of Authorization.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... MAMMALS Taking Marine Mammals Incidental to Conducting Precision Strike Weapon Missions in the Gulf of Mexico § 216.257 Letters of Authorization. (a) A Letter of Authorization, unless suspended or...

  6. 50 CFR 216.257 - Letters of Authorization.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... MAMMALS Taking Marine Mammals Incidental to Conducting Precision Strike Weapon Missions in the Gulf of Mexico § 216.257 Letters of Authorization. (a) A Letter of Authorization, unless suspended or...

  7. 50 CFR 218.237 - Applications for Letters of Authorization.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Array Sensor System Low Frequency Active (SURTASS LFA) Sonar § 218.237 Applications for Letters of... scheduled to begin conducting SURTASS LFA sonar operations or the previous Letter of Authorization...

  8. 50 CFR 216.187 - Applications for Letters of Authorization.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Array Sensor System Low Frequency Active (SURTASS LFA sonar) Sonar § 216.187 Applications for Letters of... scheduled to begin conducting SURTASS LFA sonar operations or the previous Letter of Authorization...

  9. 50 CFR 218.237 - Applications for Letters of Authorization.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Array Sensor System Low Frequency Active (SURTASS LFA) Sonar § 218.237 Applications for Letters of... scheduled to begin conducting SURTASS LFA sonar operations or the previous Letter of Authorization...

  10. 50 CFR 216.187 - Applications for Letters of Authorization.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Array Sensor System Low Frequency Active (SURTASS LFA sonar) Sonar § 216.187 Applications for Letters of... scheduled to begin conducting SURTASS LFA sonar operations or the previous Letter of Authorization...

  11. 50 CFR 218.16 - Letters of Authorization.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... MAMMALS Taking Marine Mammals Incidental to U.S. Navy Training in the Jacksonville Range Complex (JAX Range Complex) § 218.16 Letters of Authorization. (a) A Letter of Authorization, unless suspended...

  12. 50 CFR 216.277 - Letters of Authorization.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... MAMMALS Taking Marine Mammals Incidental to U.S. Navy Training in the Southern California Range Complex (SOCAL Range Complex) § 216.277 Letters of Authorization. (a) A Letter of Authorization, unless...

  13. 50 CFR 218.7 - Letters of Authorization.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... MAMMALS Taking Marine Mammals Incidental to U.S. Navy Training in the Virginia Capes Range Complex (VACAPES Range Complex) § 218.7 Letters of Authorization. (a) A Letter of Authorization, unless...

  14. 46 CFR 3.05-1 - Letter of designation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... OCEANOGRAPHIC RESEARCH VESSELS Definition of Terms Used in This Part § 3.05-1 Letter of designation. A letter issued by an Officer in Charge, Marine Inspection, designating an uninspected vessel as an...

  15. 50 CFR 218.176 - Letters of Authorization.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Complex and the Associated Proposed Extensions Study Area § 218.176 Letters of Authorization. (a) A Letter... determination that the total number of marine mammals taken by the activity as a whole will have no more than...

  16. 50 CFR 217.76 - Letter of Authorization.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Kodiak Launch Complex, Alaska § 217.76 Letter of Authorization. (a) A Letter of Authorization, unless... number of marine mammals, by species and age class, authorized to be taken; (2) Permissible methods...

  17. The Letters Not Sent by a Journal Editor

    NASA Astrophysics Data System (ADS)

    2013-04-01

    In the late hours of the night, even the most conscientious of journal editors may slip into writing imaginary letters to cherished authors and reviewers. Here are some of the letters that I composed:

  18. EPA Letters to the Department of Treasury (IRS) for FRAP

    EPA Pesticide Factsheets

    EPA letter of request (December 13, 2012) and letter of reply (April 30, 2013) to IRS to address FRAP commitment to facilitate the deductibility of radon testing and mitigation costs within Health Care Savings Accounts (HSAs).

  19. Impaired acquisition of novel grapheme-color correspondences in synesthesia.

    PubMed

    Brang, David; Ghiam, Michael; Ramachandran, Vilayanur S

    2013-01-01

    Grapheme-color synesthesia is a neurological phenomenon in which letters and numbers (graphemes) consistently evoke particular colors (e.g., A may be experienced as red). These sensations are thought to arise through the cross-activation of grapheme processing regions in the fusiform gyrus and color area V4, supported by anatomical and functional imaging. However, the developmental onset of grapheme-color synesthesia remains elusive as research in this area has largely relied on self-report of these experiences in children. One possible account suggests that synesthesia is present at or near birth and initially binds basic shapes and forms to colors, which are later refined to grapheme-color associations through experience. Consistent with this view, studies show that similarly shaped letters and numbers tend to elicit similar colors in synesthesia and that some synesthetes consciously associate basic shapes with colors; research additionally suggests that synesthetic colors can emerge for newly learned characters with repeated presentation. This model further predicts that the initial shape-color correspondences in synesthesia may persist as implicit associations, driving the acquisition of colors for novel characters. To examine the presence of latent color associations for novel characters, synesthetes and controls were trained on pre-defined associations between colors and complex shapes, on the assumption that the prescribed shape-color correspondences would on average differ from implicit synesthetic associations. Results revealed synesthetes were less accurate than controls to learn novel shape-color associations, consistent with our suggestion that implicit form-color associations conflicted with the learned pairings.

  20. When writing impairs reading: letter perception's susceptibility to motor interference.

    PubMed

    James, Karin H; Gauthier, Isabel

    2009-08-01

    The effect of writing on the concurrent visual perception of letters was investigated in a series of studies using an interference paradigm. Participants drew shapes and letters while simultaneously visually identifying letters and shapes embedded in noise. Experiments 1-3 demonstrated that letter perception, but not the perception of shapes, was affected by motor interference. This suggests a strong link between the perception of letters and the neural substrates engaged during writing. The overlap both in category (letter vs. shape) and in the perceptual similarity of the features (straight vs. curvy) of the seen and drawn items determined the amount of interference. Experiment 4 demonstrated that intentional production of letters is not necessary for the interference to occur, because passive movement of the hand in the shape of letters also interfered with letter perception. When passive movements were used, however, only the category of the drawn items (letters vs. shapes), but not the perceptual similarity, had an influence, suggesting that motor representations for letters may selectively influence visual perception of letters through proprioceptive feedback, with an additional influence of perceptual similarity that depends on motor programs.

  1. The Castleman Letter: A Classroom Exercise in Critical Thinking.

    ERIC Educational Resources Information Center

    Shapiro, Victor W.

    1981-01-01

    Describes a critical thinking activity for secondary school social studies students using a letter written in the nineteenth century. The letter contains references to unfamiliar people and events. Through research, students are able to trace the exact date of the letter and to identify the people and events. (KC)

  2. 33 CFR 401.68 - Explosives Permission Letter.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Explosives Permission Letter. 401..., DEPARTMENT OF TRANSPORTATION SEAWAY REGULATIONS AND RULES Regulations Dangerous Cargo § 401.68 Explosives Permission Letter. (a) A Seaway Explosives Permission Letter is required for an explosive vessel in...

  3. 33 CFR 401.68 - Explosives Permission Letter.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 3 2012-07-01 2012-07-01 false Explosives Permission Letter. 401..., DEPARTMENT OF TRANSPORTATION SEAWAY REGULATIONS AND RULES Regulations Dangerous Cargo § 401.68 Explosives Permission Letter. (a) A Seaway Explosives Permission Letter is required for an explosive vessel in...

  4. 33 CFR 401.68 - Explosives Permission Letter.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Explosives Permission Letter. 401..., DEPARTMENT OF TRANSPORTATION SEAWAY REGULATIONS AND RULES Regulations Dangerous Cargo § 401.68 Explosives Permission Letter. (a) A Seaway Explosives Permission Letter is required for an explosive vessel in...

  5. 33 CFR 401.68 - Explosives Permission Letter.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 3 2013-07-01 2013-07-01 false Explosives Permission Letter. 401..., DEPARTMENT OF TRANSPORTATION SEAWAY REGULATIONS AND RULES Regulations Dangerous Cargo § 401.68 Explosives Permission Letter. (a) A Seaway Explosives Permission Letter is required for an explosive vessel in...

  6. 33 CFR 401.68 - Explosives permission letter.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 3 2014-07-01 2014-07-01 false Explosives permission letter. 401..., DEPARTMENT OF TRANSPORTATION SEAWAY REGULATIONS AND RULES Regulations Dangerous Cargo § 401.68 Explosives permission letter. (a) A Seaway Explosives Permission Letter is required for an explosive vessel in...

  7. 19 CFR 162.4 - Search for letters.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 2 2011-04-01 2011-04-01 false Search for letters. 162.4 Section 162.4 Customs... (CONTINUED) INSPECTION, SEARCH, AND SEIZURE Inspection, Examination, and Search § 162.4 Search for letters. A Customs officer may search vessels for letters which may be on board or may have been conveyed contrary...

  8. 19 CFR 162.4 - Search for letters.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 2 2010-04-01 2010-04-01 false Search for letters. 162.4 Section 162.4 Customs... (CONTINUED) INSPECTION, SEARCH, AND SEIZURE Inspection, Examination, and Search § 162.4 Search for letters. A Customs officer may search vessels for letters which may be on board or may have been conveyed contrary...

  9. 76 FR 63237 - Issuance of Investigation Completion Letters

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-12

    ... Part 571 RIN 3141-AA49 Issuance of Investigation Completion Letters AGENCY: National Indian Gaming... regulations to provide for an investigation completion letter to be issued to a Tribe if the Agency's... a process for issuing an investigation completion letter. The Notice of Regulatory Review...

  10. 50 CFR 218.16 - Letters of Authorization.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... MAMMALS Taking Marine Mammals Incidental to U.S. Navy Training in the Jacksonville Range Complex (JAX Range Complex) § 218.16 Letters of Authorization. (a) A Letter of Authorization, unless suspended or... and renewal of the Letter of Authorization will be based on a determination that the total number...

  11. 50 CFR 218.7 - Letters of Authorization.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... MAMMALS Taking Marine Mammals Incidental to U.S. Navy Training in the Virginia Capes Range Complex (VACAPES Range Complex) § 218.7 Letters of Authorization. (a) A Letter of Authorization, unless suspended... and renewal of the Letter of Authorization will be based on a determination that the total number...

  12. 50 CFR 216.277 - Letters of Authorization.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... MAMMALS Taking Marine Mammals Incidental to U.S. Navy Training in the Southern California Range Complex (SOCAL Range Complex) § 216.277 Letters of Authorization. (a) A Letter of Authorization, unless suspended... and renewal of the Letter of Authorization will be based on a determination that the total number...

  13. Transposed-Letter and Laterality Effects in Lexical Decision

    ERIC Educational Resources Information Center

    Perea, Manuel; Fraga, Isabel

    2006-01-01

    Two divided visual field lexical decision experiments were conducted to examine the role of the cerebral hemispheres in transposed-letter similarity effects. In Experiment 1, we created two types of nonwords: nonadjacent transposed-letter nonwords ("TRADEGIA"; the base word was "TRAGEDIA," the Spanish for "TRAGEDY") and two-letter different…

  14. 48 CFR 871.201-4 - Letter contracts.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 5 2014-10-01 2014-10-01 false Letter contracts. 871.201... Rehabilitation and Employment Service 871.201-4 Letter contracts. Letter contracts are authorized for use in... formal contract with an approved educational institution before the enrollment of eligible veterans...

  15. 48 CFR 871.201-4 - Letter contracts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Letter contracts. 871.201... Rehabilitation and Employment Service 871.201-4 Letter contracts. Letter contracts are authorized for use in... formal contract with an approved educational institution before the enrollment of eligible veterans...

  16. 48 CFR 871.201-4 - Letter contracts.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 5 2012-10-01 2012-10-01 false Letter contracts. 871.201... Rehabilitation and Employment Service 871.201-4 Letter contracts. Letter contracts are authorized for use in... formal contract with an approved educational institution before the enrollment of eligible veterans...

  17. 22 CFR 92.54 - “Letters rogatory” defined.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false âLetters rogatoryâ defined. 92.54 Section 92.54 Foreign Relations DEPARTMENT OF STATE LEGAL AND RELATED SERVICES NOTARIAL AND RELATED SERVICES Depositions and Letters Rogatory § 92.54 “Letters rogatory” defined. In its broader sense in...

  18. The Letter of Recommendation: A Key to Women's Career Equity.

    ERIC Educational Resources Information Center

    Cowan, Gloria; Kasen, Jill

    A critical piece of information in the selection process for academic positions is the letter of recommendation. A study was conducted to determine if differences exist in the letters written for female versus male candidates for academic positions. Using letters which were retyped to avoid personal, institutional, and sex-specific identification,…

  19. 31 CFR 535.416 - Letters of credit.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Letters of credit. 535.416 Section... § 535.416 Letters of credit. (a) Question. Prior to the effective date, a bank subject to the jurisdiction of the United States has issued or confirmed a documentary letter of credit for a...

  20. 48 CFR 52.228-14 - Irrevocable Letter of Credit.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Credit. 52.228-14 Section 52.228-14 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION....228-14 Irrevocable Letter of Credit. As prescribed in 28.204-4, insert the following clause: Irrevocable Letter of Credit (DEC 1999) (a) “Irrevocable letter of credit” (ILC), as used in this...

  1. 48 CFR 52.228-14 - Irrevocable Letter of Credit.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Credit. 52.228-14 Section 52.228-14 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION....228-14 Irrevocable Letter of Credit. As prescribed in 28.204-4, insert the following clause: Irrevocable Letter of Credit (MAY 2014) (a) “Irrevocable letter of credit” (ILC), as used in this...

  2. 31 CFR 535.416 - Letters of credit.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Letters of credit. 535.416 Section 535... § 535.416 Letters of credit. (a) Question. Prior to the effective date, a bank subject to the jurisdiction of the United States has issued or confirmed a documentary letter of credit for a...

  3. 47 CFR 54.1007 - Letter of credit.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 3 2012-10-01 2012-10-01 false Letter of credit. 54.1007 Section 54.1007... SERVICE Mobility Fund § 54.1007 Letter of credit. (a) Before being authorized to receive Mobility Fund Phase I support, a winning bidder shall obtain an irrevocable standby letter of credit which shall...

  4. 47 CFR 54.1007 - Letter of credit.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 3 2013-10-01 2013-10-01 false Letter of credit. 54.1007 Section 54.1007... SERVICE Mobility Fund § 54.1007 Letter of credit. (a) Before being authorized to receive Mobility Fund Phase I support, a winning bidder shall obtain an irrevocable standby letter of credit which shall...

  5. 40 CFR 280.99 - Letter of credit.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 28 2013-07-01 2013-07-01 false Letter of credit. 280.99 Section 280... (UST) Financial Responsibility § 280.99 Letter of credit. (a) An owner or operator may satisfy the requirements of § 280.93 by obtaining an irrevocable standby letter of credit that conforms to the...

  6. 31 CFR 535.416 - Letters of credit.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance:Treasury 3 2014-07-01 2014-07-01 false Letters of credit. 535.416 Section 535... § 535.416 Letters of credit. (a) Question. Prior to the effective date, a bank subject to the jurisdiction of the United States has issued or confirmed a documentary letter of credit for a...

  7. 48 CFR 52.228-14 - Irrevocable Letter of Credit.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Credit. 52.228-14 Section 52.228-14 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION....228-14 Irrevocable Letter of Credit. As prescribed in 28.204-4, insert the following clause: Irrevocable Letter of Credit (DEC 1999) (a) “Irrevocable letter of credit” (ILC), as used in this...

  8. 48 CFR 52.228-14 - Irrevocable Letter of Credit.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Credit. 52.228-14 Section 52.228-14 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION....228-14 Irrevocable Letter of Credit. As prescribed in 28.204-4, insert the following clause: Irrevocable Letter of Credit (DEC 1999) (a) “Irrevocable letter of credit” (ILC), as used in this...

  9. 31 CFR 535.416 - Letters of credit.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 3 2013-07-01 2013-07-01 false Letters of credit. 535.416 Section 535... § 535.416 Letters of credit. (a) Question. Prior to the effective date, a bank subject to the jurisdiction of the United States has issued or confirmed a documentary letter of credit for a...

  10. The Relationship between Letter Fluency Measures and Arabic GPA

    ERIC Educational Resources Information Center

    Al-Hmouz, Hanan

    2013-01-01

    This study investigated two widely-used early literacy skill's indicators in reflecting growth in first-grade language achievement skills. It compared two curriculum-based assessments of letter knowledge: Letter Naming Fluency (LNF) and Letter Sound Fluency (LSF) in the Arabic language. A sample of 125 first-grade students, 100 average readers and…

  11. 46 CFR 131.930 - Display of stability letter.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Display of stability letter. 131.930 Section 131.930 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS OPERATIONS Miscellaneous § 131.930 Display of stability letter. If the Coast Guard issues a stability letter under §...

  12. 46 CFR 131.930 - Display of stability letter.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Display of stability letter. 131.930 Section 131.930 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS OPERATIONS Miscellaneous § 131.930 Display of stability letter. If the Coast Guard issues a stability letter under §...

  13. 46 CFR 131.930 - Display of stability letter.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Display of stability letter. 131.930 Section 131.930 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS OPERATIONS Miscellaneous § 131.930 Display of stability letter. If the Coast Guard issues a stability letter under §...

  14. 46 CFR 131.930 - Display of stability letter.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Display of stability letter. 131.930 Section 131.930 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS OPERATIONS Miscellaneous § 131.930 Display of stability letter. If the Coast Guard issues a stability letter under §...

  15. 46 CFR 131.930 - Display of stability letter.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Display of stability letter. 131.930 Section 131.930 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS OPERATIONS Miscellaneous § 131.930 Display of stability letter. If the Coast Guard issues a stability letter under §...

  16. Evaluation of Patients’ Response Toward Osteoporosis Letter Intervention Versus Phone Call Plus Letter Intervention

    PubMed Central

    O’Brien, Lisa K.; Armstrong, April D.; Hassenbein, Susan E.

    2015-01-01

    Introduction: The aim of this study was to compare the effectiveness of 2 interventions in prompting patients to obtain osteoporosis follow-up after a fracture. Our hypothesis was that a phone call plus letter would yield greater response toward osteoporosis evaluation versus a letter alone to patients after sustaining a fragility fracture. Materials and Methods: Prospective study randomized 141 patients age 50 years and older with a fragility fracture into 3 groups for comparison. Group 1 (letter only) patients received a letter 3 months after their diagnosis of fracture indicating their risk for osteoporosis and urging them to follow-up for evaluation. Group 2 (phone call plus letter) patients were contacted via phone 3 months after their diagnosis of fracture. A letter followed the phone call. Group 3 (control) patients were neither contacted via phone nor sent a letter. All groups were contacted via phone 6 months after their initial visit to determine if they followed up for evaluation. Results: In group 1, 23 (52.27%) of 44 had follow-up, and 21 (47.73%) of 44 did not follow-up. In group 2, 30 (62.5%) of 48 had follow-up, and 18 (37.50%) of 48 did not follow-up. In group 3, 6 (12.24%) of 49 had some sort of follow-up, and 43 (87.76%) of 49 did not have any follow-up. A statistical significance was achieved between group 3 (control) and both groups 1 and 2 with regard to follow-up (P < .0001). The results did not show a statistically significant difference between Groups 1 and 2, however, there was a trend toward improved response with a phone call plus letter (P = .321). Conclusion: A more personalized approach with a phone call plus follow-up letter to patients increased osteoporosis follow-up care by an additional 10%, however, this was not a statistically significant difference from just sending out a letter alone. PMID:26623157

  17. Letters of credit getting more expensive.

    PubMed

    Nemes, J

    1991-09-02

    Hospital executives who haven't been in the market recently for a new or renewed letter of credit will find it a more expensive way to back their variable-rate debt. Annual fees are surging, for reasons ranging from an international banking agreement that goes into effect next year to more conservative fee structures being instituted because of bad loans made by some banks in the past decade.

  18. Essay: reflections on Physical Review Letters.

    PubMed

    Lazarus, David

    2008-08-01

    During my tenure as APS Editor-in-Chief Physical Review Letters changed from a journal whose authors were mostly from the U.S. to one whose authors were mostly from abroad. I encouraged authors to publicize their work even before their papers were accepted for publication. And I sought to raise the quality of the papers that were published even higher than before.

  19. Simulation study of stimulation parameters in desynchronisation based on the Hodgkin-Huxley small-world neural networks and its possible implications for vagus nerve stimulation.

    PubMed

    Li, Yan-Long; Chen, Zhao-Yang; Ma, Jun; Chen, Yu-Hong

    2008-02-01

    Adopting small-world neural networks of the Hodgkin-Huxley (HH) model, the stimulation parameters in desynchronisation and its possible implications for vagus nerve stimulation (VNS) are numerically investigated. With the synchronisation status of networks to represent epilepsy, then, adding pulse to stimulations to 10% of neurons to simulate the VNS, we obtain the desynchronisation status of networks (representing antiepileptic effects). The simulations show that synchronisation evolves into desynchronisation in the HH neural networks when a part (10%) of neurons are stimulated with a pulse current signal. The network desynchronisation appears to be sensitive to the stimulation parameters. For the case of the same stimulation intensity, weakly coupled networks reach desynchronisation more easily than strongly coupled networks. The network desynchronisation reduced by short-stimulation interval is more distinct than that of induced by long stimulation interval. We find that there exist the optimal stimulation interval and optimal stimulation intensity when the other stimulation parameters remain certain.

  20. CROSS-DISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY: Environmental Impacts on Spiking Properties in Hodgkin-Huxley Neuron with Direct Current Stimulus

    NASA Astrophysics Data System (ADS)

    Yuan, Chang-Qing; Zhao, Tong-Jun; Zhan, Yong; Zhang, Su-Hua; Liu, Hui; Zhang, Yu-Hong

    2009-11-01

    Based on the well accepted Hodgkin-Huxley neuron model, the neuronal intrinsic excitability is studied when the neuron is subject to varying environmental temperatures, the typical impact for its regulating ways. With computer simulation, it is found that altering environmental temperature can improve or inhibit the neuronal intrinsic excitability so as to influence the neuronal spiking properties. The impacts from environmental factors can be understood that the neuronal spiking threshold is essentially influenced by the fluctuations in the environment. With the environmental temperature varying, burst spiking is realized for the neuronal membrane voltage because of the environment-dependent spiking threshold. This burst induced by changes in spiking threshold is different from that excited by input currents or other stimulus.

  1. 28 CFR 540.19 - Legal correspondence.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 28 Judicial Administration 2 2013-07-01 2013-07-01 false Legal correspondence. 540.19 Section 540... WITH PERSONS IN THE COMMUNITY Correspondence § 540.19 Legal correspondence. (a) Staff shall mark each.... (b) The inmate is responsible for advising any attorney that correspondence will be handled...

  2. 37 CFR 41.10 - Correspondence addresses.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2011-07-01 2011-07-01 false Correspondence addresses. 41....10 Correspondence addresses. Except as the Board may otherwise direct, (a) Appeals. Correspondence in... all other correspondence in an application or a patent involved in an appeal to the Board for which...

  3. 48 CFR 852.236-76 - Correspondence.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Correspondence. 852.236-76... SOLICITATION PROVISIONS AND CONTRACT CLAUSES Texts of Provisions and Clauses 852.236-76 Correspondence. As prescribed in 836.570, insert the following clause: Correspondence (APR 1984) All correspondence relative...

  4. 21 CFR 20.103 - Correspondence.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 1 2012-04-01 2012-04-01 false Correspondence. 20.103 Section 20.103 Food and... Availability of Specific Categories of Records § 20.103 Correspondence. (a) All correspondence to and from... for public disclosure. (b) Any such correspondence is available for public disclosure at the time...

  5. 48 CFR 852.236-76 - Correspondence.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 5 2012-10-01 2012-10-01 false Correspondence. 852.236-76... SOLICITATION PROVISIONS AND CONTRACT CLAUSES Texts of Provisions and Clauses 852.236-76 Correspondence. As prescribed in 836.570, insert the following clause: Correspondence (APR 1984) All correspondence relative...

  6. 28 CFR 540.19 - Legal correspondence.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 28 Judicial Administration 2 2012-07-01 2012-07-01 false Legal correspondence. 540.19 Section 540... WITH PERSONS IN THE COMMUNITY Correspondence § 540.19 Legal correspondence. (a) Staff shall mark each.... (b) The inmate is responsible for advising any attorney that correspondence will be handled...

  7. 21 CFR 20.103 - Correspondence.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Correspondence. 20.103 Section 20.103 Food and... Availability of Specific Categories of Records § 20.103 Correspondence. (a) All correspondence to and from... for public disclosure. (b) Any such correspondence is available for public disclosure at the time...

  8. 37 CFR 41.10 - Correspondence addresses.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2012-07-01 2012-07-01 false Correspondence addresses. 41....10 Correspondence addresses. Except as the Board may otherwise direct, (a) Appeals. Correspondence in... all other correspondence in an application or a patent involved in an appeal to the Board for which...

  9. 37 CFR 41.10 - Correspondence addresses.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false Correspondence addresses. 41....10 Correspondence addresses. Except as the Board may otherwise direct, (a) Appeals. Correspondence in... all other correspondence in an application or a patent involved in an appeal to the Board for which...

  10. 37 CFR 41.10 - Correspondence addresses.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2014-07-01 2014-07-01 false Correspondence addresses. 41... Correspondence addresses. Except as the Board may otherwise direct, (a) Appeals. Correspondence in an application... correspondence in an application or a patent involved in an appeal to the Board for which an address is...

  11. 28 CFR 540.19 - Legal correspondence.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 28 Judicial Administration 2 2011-07-01 2011-07-01 false Legal correspondence. 540.19 Section 540... WITH PERSONS IN THE COMMUNITY Correspondence § 540.19 Legal correspondence. (a) Staff shall mark each.... (b) The inmate is responsible for advising any attorney that correspondence will be handled...

  12. 21 CFR 20.103 - Correspondence.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 1 2013-04-01 2013-04-01 false Correspondence. 20.103 Section 20.103 Food and... Availability of Specific Categories of Records § 20.103 Correspondence. (a) All correspondence to and from... for public disclosure. (b) Any such correspondence is available for public disclosure at the time...

  13. 28 CFR 540.19 - Legal correspondence.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Legal correspondence. 540.19 Section 540... WITH PERSONS IN THE COMMUNITY Correspondence § 540.19 Legal correspondence. (a) Staff shall mark each.... (b) The inmate is responsible for advising any attorney that correspondence will be handled...

  14. 48 CFR 852.236-76 - Correspondence.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 5 2013-10-01 2013-10-01 false Correspondence. 852.236-76... SOLICITATION PROVISIONS AND CONTRACT CLAUSES Texts of Provisions and Clauses 852.236-76 Correspondence. As prescribed in 836.570, insert the following clause: Correspondence (APR 1984) All correspondence relative...

  15. 37 CFR 41.10 - Correspondence addresses.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2013-07-01 2013-07-01 false Correspondence addresses. 41... Correspondence addresses. Except as the Board may otherwise direct, (a) Appeals. Correspondence in an application... correspondence in an application or a patent involved in an appeal to the Board for which an address is...

  16. 28 CFR 540.19 - Legal correspondence.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 28 Judicial Administration 2 2014-07-01 2014-07-01 false Legal correspondence. 540.19 Section 540... WITH PERSONS IN THE COMMUNITY Correspondence § 540.19 Legal correspondence. (a) Staff shall mark each.... (b) The inmate is responsible for advising any attorney that correspondence will be handled...

  17. 21 CFR 20.103 - Correspondence.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 1 2014-04-01 2014-04-01 false Correspondence. 20.103 Section 20.103 Food and... Availability of Specific Categories of Records § 20.103 Correspondence. (a) All correspondence to and from... for public disclosure. (b) Any such correspondence is available for public disclosure at the time...

  18. 48 CFR 852.236-76 - Correspondence.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Correspondence. 852.236-76... SOLICITATION PROVISIONS AND CONTRACT CLAUSES Texts of Provisions and Clauses 852.236-76 Correspondence. As prescribed in 836.570, insert the following clause: Correspondence (APR 1984) All correspondence relative...

  19. 21 CFR 20.103 - Correspondence.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Correspondence. 20.103 Section 20.103 Food and... Availability of Specific Categories of Records § 20.103 Correspondence. (a) All correspondence to and from... for public disclosure. (b) Any such correspondence is available for public disclosure at the time...

  20. 48 CFR 852.236-76 - Correspondence.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 5 2014-10-01 2014-10-01 false Correspondence. 852.236-76... SOLICITATION PROVISIONS AND CONTRACT CLAUSES Texts of Provisions and Clauses 852.236-76 Correspondence. As prescribed in 836.570, insert the following clause: Correspondence (APR 1984) All correspondence relative...

  1. The Virginia Racial Integrity Act revisited: the Plecker-Laughlin correspondence: 1928-1930.

    PubMed

    Reilly, P

    1983-12-01

    Correspondence between Walter Ashby Plecker, Virginia State Registrar of Vital Statistics between 1912 and 1938, and Harry Hamilton Laughlin, Superintendent of the Eugenics Record Office at Cold Spring Harbor between 1910 and 1939, provides evidence of efforts to enforce the Virginia Racial Integrity Act of 1924. After antimiscegenation policy is placed in a historical context, excerpts from the letters are offered to demonstrate the zeal with which one state official pursued this "eugenic" policy.

  2. Gender differences in recommendation letters for postdoctoral fellowships in geoscience

    NASA Astrophysics Data System (ADS)

    Dutt, Kuheli; Pfaff, Danielle L.; Bernstein, Ariel F.; Dillard, Joseph S.; Block, Caryn J.

    2016-11-01

    Gender disparities in the fields of science, technology, engineering and mathematics, including the geosciences, are well documented and widely discussed. In the geosciences, despite receiving 40% of doctoral degrees, women hold less than 10% of full professorial positions. A significant leak in the pipeline occurs during postdoctoral years, so biases embedded in postdoctoral processes, such as biases in recommendation letters, may be deterrents to careers in geoscience for women. Here we present an analysis of an international data set of 1,224 recommendation letters, submitted by recommenders from 54 countries, for postdoctoral fellowships in the geosciences over the period 2007-2012. We examine the relationship between applicant gender and two outcomes of interest: letter length and letter tone. Our results reveal that female applicants are only half as likely to receive excellent letters versus good letters compared to male applicants. We also find no evidence that male and female recommenders differ in their likelihood to write stronger letters for male applicants over female applicants. Our analysis also reveals significant regional differences in letter length, with letters from the Americas being significantly longer than any other region, whereas letter tone appears to be distributed equivalently across all world regions. These results suggest that women are significantly less likely to receive excellent recommendation letters than their male counterparts at a critical juncture in their career.

  3. Neural correlates of letter reversal in children and adults.

    PubMed

    Blackburne, Liwei King; Eddy, Marianna D; Kalra, Priya; Yee, Debbie; Sinha, Pawan; Gabrieli, John D E

    2014-01-01

    Children often make letter reversal errors when first learning to read and write, even for letters whose reversed forms do not appear in normal print. However, the brain basis of such letter reversal in children learning to read is unknown. The present study compared the neuroanatomical correlates (via functional magnetic resonance imaging) and the electrophysiological correlates (via event-related potentials or ERPs) of this phenomenon in children, ages 5-12, relative to young adults. When viewing reversed letters relative to typically oriented letters, adults exhibited widespread occipital, parietal, and temporal lobe activations, including activation in the functionally localized visual word form area (VWFA) in left occipito-temporal cortex. Adults exhibited significantly greater activation than children in all of these regions; children only exhibited such activation in a limited frontal region. Similarly, on the P1 and N170 ERP components, adults exhibited significantly greater differences between typical and reversed letters than children, who failed to exhibit significant differences between typical and reversed letters. These findings indicate that adults distinguish typical and reversed letters in the early stages of specialized brain processing of print, but that children do not recognize this distinction during the early stages of processing. Specialized brain processes responsible for early stages of letter perception that distinguish between typical and reversed letters may develop slowly and remain immature even in older children who no longer produce letter reversals in their writing.

  4. Word Boxes Improve Phonemic Awareness, Letter-Sound Correspondences, and Spelling Skills of At-Risk Kindergartners

    ERIC Educational Resources Information Center

    Keesey, Susan; Konrad, Moira; Joseph, Laurice M.

    2015-01-01

    Early literacy skills are critical for success in school, yet many children fail to obtain these skills in a timely manner leaving them unable to perform at minimal academic expectations. The purpose of this study was to examine the effects of word box instruction, a research-based intervention designed to promote phonemic awareness, on the…

  5. Letter from Seoul: Correspondence from the International Arts Education Symposium and the Asia-Pacific Regional Conference

    ERIC Educational Resources Information Center

    Aprill, Arnold; Schroeder-Yu, Gigi

    2006-01-01

    Arts educator Gigi Schroeder-Yu and Arnold Aprill arrived in Seoul, Korea to participate in the International Arts Education Symposium and in the Asia-Pacific Regional Conference that are part of the wind up for the pitch of the UNESCO World Conference on Arts Education to be held in Lisbon in March 2006. In this article, they reflect on their…

  6. Learning of Letter Names and Sounds and Their Contribution to Word Recognition

    ERIC Educational Resources Information Center

    Levin, Iris; Shatil-Carmon, Sivan; Asif-Rave, Ornit

    2006-01-01

    This study investigated knowledge of letter names and letter sounds, their learning, and their contributions to word recognition. Of 123 preschoolers examined on letter knowledge, 65 underwent training on both letter names and letter sounds in a counterbalanced order. Prior to training, children were more advanced in associating letters with their…

  7. [The correspondence of Johann Bartholomäus Trommsdorff (1770-1837): more then a source book of pharmaceutical history].

    PubMed

    Bettin, Hartmut; Friedrich, Christoph

    2002-09-01

    The aim of this paper is to present the publication of the correspondence of Johann Bartholomäus Trommsdorff (1770 bis 1837) and to inform about the history of this project as well as the methodical proceedings and the content of these letters. The opportunities and limitations of the modern Trommsdorff research, based on the publication of his correspondence, will be shown. His contacts have been manifold and expansive. He corresponded with many famous scientists in pharmacy, chemistry, medicine and with important people of intellectual origin. Trommsdorff was a highly important person of the international European relationships in the field of pharmacy. Many publications certify the importance of the Trommsdorff-correspondence. The publication of these letters has opened new biographical aspects and allows to follow the connections and ways of communication in the new age of the foundation of scientific pharmacy.

  8. Designability and cooperative folding in a four-letter hydrophobic-polar model of proteins

    NASA Astrophysics Data System (ADS)

    Liu, Hai-Guang; Tang, Lei-Han

    2006-11-01

    The two-letter hydrophobic-polar (HP) model of Lau and Dill [Macromolecules 22, 3986 (1989)] has been widely used in theoretical studies of protein folding due to its conceptual and computational simplicity. Despite its success in elucidating various aspects of the sequence-structure relationship, thermodynamic behavior of the model is not in agreement with a sharp two-state folding transition of many single-domain proteins. To gain a better understanding of this discrepancy, we consider an extension of the HP model by including an “antiferromagnetic” (AF) interaction in the contact potential that favors amino acid residues with complementary attributes. With an enlarged four-letter alphabet, the density of states on the low energy side can be significantly decreased. Computational studies of the four-letter HP model are performed on 36-mer sequences on a square lattice. It is found that the designability of folded structures in the extended model exhibits strong correlation with that of the two-letter HP model, while the AF interaction alone selects a very different class of structures that resembles the Greek key motif for beta sheets. A procedure is introduced to select sequences which have the largest energy gap to the native state. Based on density of states and specific heat calculations in the full configuration space, we show that the optimized sequence is able to fold nearly as cooperatively as a corresponding Gō model.

  9. `Dear Professor Dyson': Twenty years of correspondence between Freeman Dyson and undergraduate students

    NASA Astrophysics Data System (ADS)

    Neuenschwander, Dwight E.

    2014-03-01

    For twenty years the students in my "Science, Technology, and Society" course, where we use Disturbing the Universe as a textbook, have corresponded with Professor Dyson. That someone of Professor Dyson's standing consistently makes a priority of promptly answering the letters of undergraduate students from all academic majors, and does so with grace and kindness, insight and wisdom, offers a personal glimpse into his character and integrity. On behalf of my students, and as a way of publicly thanking Professor Dyson for participating in our course conversations, I am honored to share samples of our correspondence with him over the years, including student reflections on his involvement in their education.

  10. `DEAR Professor DYSON:' Twenty Years of Correspondence Between Freeman Dyson and Undergraduate Students

    NASA Astrophysics Data System (ADS)

    Neuenschwander, Dwight E.

    2014-04-01

    For twenty years the students in my "Science, Technology, and Society" course, where we use Disturbing the Universe as a textbook, have corresponded with Professor Dyson. That someone of Professor Dyson's standing consistently makes a priority of promptly answering the letters of undergraduate students from all academic majors, and does so with grace and kindness, insight and wisdom, offers a personal glimpse into his character and integrity. On behalf of my students, and as a way of publicly thanking Professor Dyson for participating in our course conversations, I am honored to share samples of our correspondence with him over the years, including student reflections on his involvement in their education.

  11. A Dialogical Model for Business Correspondence.

    ERIC Educational Resources Information Center

    Mendelson, Michael

    1993-01-01

    Combines the ideas of Erasmus, the Renaissance humanist, and Bakhtin, the twentieth-century Russian philosopher, into a unified theory of business correspondence. Presents both a set of guidelines and a model for the practice of dialogical correspondence. (SR)

  12. Communication: The Readability of Business Correspondence.

    ERIC Educational Resources Information Center

    Mitzner, Carol; Schramm, Dwayne

    1980-01-01

    A study that examined correspondence from 15 different business areas found the writing of that correspondence to be at a reading level higher than the average educational level of U.S. citizens. (LRA)

  13. A letter to the chief executive.

    PubMed

    Fuller, Joseph

    2002-10-01

    Beyond the recent accounting scandals, something is wrong with the way most companies are managed today. That's the message of this fictional letter from a board member to a CEO, written by Joseph Fuller, CEO of strategy consulting firm the Monitor Group. The letter highlights the challenges and complexities of running a business in today's uncertain environment. And while it avoids the facile bashing of U.S. executives so common these days, the missive nonetheless casts a harsh light on the flaws that have recently been exposed in the American management model. The letter addresses a single CEO and company, yet it is intended to speak to executives and boards everywhere: "It wasn't the recession that caused us to make three acquisitions in two years at very, very high prices; the need to fuel [unreasonable] growth did. Nor was it the recession that caused us to expand our capacity in anticipation of gaining market share; rather, it was our own overly optimistic sales forecasts that led us to that decision. Where did those forecasts originate? From line managers trying to fulfill profit goals that we created after meeting with the analysts. "The root cause of many of the problems that became apparent in the last 24 months lies not with the economy, not with September 11, and not with the dot-com bubble. Rather, it lies with that willingness to be led by outside forces-indeed, our own lack of conviction about setting a course." Restoring sound, strategic decision making--thinking that looks beyond tomorrow's analyst reports--will go a long way toward keeping those outside forces at bay, according to Fuller.

  14. Letter report: Ari Patrinos -- ARM summary

    SciTech Connect

    MacDonald, G.J.; Ruderman, M.A.; Treiman, S.B.

    1995-07-27

    This letter report provides a summary of the authors` views on ARM. ARM is a highly focused program designed to improve understanding of the transport of infrared and solar radiation through the atmosphere. The program pays particular attention to the interaction of radiation with the three phases of water. The goals of ARM are usually articulated in terms of improvements in climate models. The authors agree that ARM can indeed make significant contributions to the understanding of climate change. In addition they believe that the results of the program will have wide applicability to a broad range of problems, including more accurate short-term and seasonal weather forecasting.

  15. 34 CFR 690.66 - Correspondence study.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 34 Education 4 2011-07-01 2011-07-01 false Correspondence study. 690.66 Section 690.66 Education... § 690.66 Correspondence study. (a) An institution calculates the Federal Pell Grant for a payment period for a student in a program of study offered by correspondence courses without terms, but not...

  16. 34 CFR 690.66 - Correspondence study.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 34 Education 4 2014-07-01 2014-07-01 false Correspondence study. 690.66 Section 690.66 Education... § 690.66 Correspondence study. (a) An institution calculates the Federal Pell Grant for a payment period for a student in a program of study offered by correspondence courses without terms, but not...

  17. 34 CFR 690.66 - Correspondence study.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 34 Education 4 2013-07-01 2013-07-01 false Correspondence study. 690.66 Section 690.66 Education... § 690.66 Correspondence study. (a) An institution calculates the Federal Pell Grant for a payment period for a student in a program of study offered by correspondence courses without terms, but not...

  18. 34 CFR 690.66 - Correspondence study.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 34 Education 4 2012-07-01 2012-07-01 false Correspondence study. 690.66 Section 690.66 Education... § 690.66 Correspondence study. (a) An institution calculates the Federal Pell Grant for a payment period for a student in a program of study offered by correspondence courses without terms, but not...

  19. 34 CFR 690.66 - Correspondence study.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 34 Education 3 2010-07-01 2010-07-01 false Correspondence study. 690.66 Section 690.66 Education... Correspondence study. (a) An institution calculates the Federal Pell Grant for a payment period for a student in a program of study offered by correspondence courses without terms, but not including...

  20. 38 CFR 4.24 - Correspondence.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2014-07-01 2014-07-01 false Correspondence. 4.24 Section 4.24 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS SCHEDULE FOR RATING DISABILITIES General Policy in Rating § 4.24 Correspondence. All correspondence relative to the...

  1. 48 CFR 42.401 - Contract correspondence.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Contract correspondence... MANAGEMENT CONTRACT ADMINISTRATION AND AUDIT SERVICES Correspondence and Visits 42.401 Contract correspondence. (a) The contracting officer (or other contracting agency personnel) normally shall (1)...

  2. 38 CFR 4.24 - Correspondence.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2011-07-01 2011-07-01 false Correspondence. 4.24 Section 4.24 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS SCHEDULE FOR RATING DISABILITIES General Policy in Rating § 4.24 Correspondence. All correspondence relative to the...

  3. 38 CFR 4.24 - Correspondence.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Correspondence. 4.24 Section 4.24 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS SCHEDULE FOR RATING DISABILITIES General Policy in Rating § 4.24 Correspondence. All correspondence relative to the...

  4. 48 CFR 836.570 - Correspondence.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 5 2012-10-01 2012-10-01 false Correspondence. 836.570... OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Contract Clauses 836.570 Correspondence. The contracting officer shall insert the clause at 852.236-76, Correspondence, in solicitations...

  5. 48 CFR 42.401 - Contract correspondence.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 1 2012-10-01 2012-10-01 false Contract correspondence... MANAGEMENT CONTRACT ADMINISTRATION AND AUDIT SERVICES Correspondence and Visits 42.401 Contract correspondence. (a) The contracting officer (or other contracting agency personnel) normally shall (1)...

  6. 48 CFR 42.401 - Contract correspondence.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 1 2013-10-01 2013-10-01 false Contract correspondence... MANAGEMENT CONTRACT ADMINISTRATION AND AUDIT SERVICES Correspondence and Visits 42.401 Contract correspondence. (a) The contracting officer (or other contracting agency personnel) normally shall (1)...

  7. 48 CFR 42.401 - Contract correspondence.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Contract correspondence... MANAGEMENT CONTRACT ADMINISTRATION AND AUDIT SERVICES Correspondence and Visits 42.401 Contract correspondence. (a) The contracting officer (or other contracting agency personnel) normally shall (1)...

  8. 48 CFR 836.570 - Correspondence.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 5 2013-10-01 2013-10-01 false Correspondence. 836.570... OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Contract Clauses 836.570 Correspondence. The contracting officer shall insert the clause at 852.236-76, Correspondence, in solicitations...

  9. 48 CFR 836.570 - Correspondence.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Correspondence. 836.570... OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Contract Clauses 836.570 Correspondence. The contracting officer shall insert the clause at 852.236-76, Correspondence, in solicitations...

  10. 76 FR 9338 - List of Correspondence

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-17

    ... of Correspondence AGENCY: Office of Special Education and Rehabilitative Services, Department of Education. ACTION: List of Correspondence from July 1, 2010 through September 30, 2010. SUMMARY: The... publish in the Federal Register a list of correspondence from the U.S. Department of Education...

  11. 48 CFR 42.401 - Contract correspondence.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 1 2014-10-01 2014-10-01 false Contract correspondence... MANAGEMENT CONTRACT ADMINISTRATION AND AUDIT SERVICES Correspondence and Visits 42.401 Contract correspondence. (a) The contracting officer (or other contracting agency personnel) normally shall (1)...

  12. 38 CFR 4.24 - Correspondence.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2012-07-01 2012-07-01 false Correspondence. 4.24 Section 4.24 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS SCHEDULE FOR RATING DISABILITIES General Policy in Rating § 4.24 Correspondence. All correspondence relative to the...

  13. 48 CFR 836.570 - Correspondence.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 5 2014-10-01 2014-10-01 false Correspondence. 836.570... OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Contract Clauses 836.570 Correspondence. The contracting officer shall insert the clause at 852.236-76, Correspondence, in solicitations...

  14. 38 CFR 4.24 - Correspondence.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2013-07-01 2013-07-01 false Correspondence. 4.24 Section 4.24 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS SCHEDULE FOR RATING DISABILITIES General Policy in Rating § 4.24 Correspondence. All correspondence relative to the...

  15. 48 CFR 836.570 - Correspondence.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Correspondence. 836.570... OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Contract Clauses 836.570 Correspondence. The contracting officer shall insert the clause at 852.236-76, Correspondence, in solicitations...

  16. The Continuity of American Letters in "The Scarlet Letter" and "The Beast in the Jungle."

    ERIC Educational Resources Information Center

    Gottschalk, Jane

    1967-01-01

    Fictional works, of different literary periods, which share a common perception of man can be explicated and compared with each other to illustrate a continuing tradition in American literature. Such a basis for comparison exists between Hawthorne's romance, "The Scarlet Letter," which appeared in 1850, and Henry James' fantasy,…

  17. ERP correlates of letter identity and letter position are modulated by lexical frequency

    PubMed Central

    Vergara-Martínez, Marta; Perea, Manuel; Gómez, Pablo; Swaab, Tamara Y.

    2013-01-01

    The encoding of letter position is a key aspect in all recently proposed models of visual-word recognition. We analyzed the impact of lexical frequency on letter position assignment by examining the temporal dynamics of lexical activation induced by pseudowords extracted from words of different frequencies. For each word (e.g., BRIDGE), we created two pseudowords: A transposed-letter (TL: BRIGDE) and a replaced-letter pseudoword (RL: BRITGE). ERPs were recorded while participants read words and pseudowords in two tasks: Semantic categorization (Experiment 1) and lexical decision (Experiment 2). For high-frequency stimuli, similar ERPs were obtained for words and TL-pseudowords, but the N400 component to words was reduced relative to RL-pseudowords, indicating less lexical/semantic activation. In contrast, TL- and RL-pseudowords created from low-frequency stimuli elicited similar ERPs. Behavioral responses in the lexical decision task paralleled this asymmetry. The present findings impose constraints on computational and neural models of visual-word recognition. PMID:23454070

  18. Letter to the editor of TAAP, in response to letter from Anders et al.

    EPA Science Inventory

    To the Editor, Toxicology and Applied Pharmacology: We would like to address the letter to the editor submitted by Anders et al. regarding the substantive issues raised regarding our paper "Evaluation of two different metabolic hypotheses for dichloromethane toxicity using physi...

  19. Integration of letters and speech sounds in the human brain.

    PubMed

    van Atteveldt, Nienke; Formisano, Elia; Goebel, Rainer; Blomert, Leo

    2004-07-22

    Most people acquire literacy skills with remarkable ease, even though the human brain is not evolutionarily adapted to this relatively new cultural phenomenon. Associations between letters and speech sounds form the basis of reading in alphabetic scripts. We investigated the functional neuroanatomy of the integration of letters and speech sounds using functional magnetic resonance imaging (fMRI). Letters and speech sounds were presented unimodally and bimodally in congruent or incongruent combinations. Analysis of single-subject data and group data aligned on the basis of individual cortical anatomy revealed that letters and speech sounds are integrated in heteromodal superior temporal cortex. Interestingly, responses to speech sounds in a modality-specific region of the early auditory cortex were modified by simultaneously presented letters. These results suggest that efficient processing of culturally defined associations between letters and speech sounds relies on neural mechanisms similar to those naturally evolved for integrating audiovisual speech.

  20. Letter report: Cold crucible melter assessment

    SciTech Connect

    Elliott, M.L.

    1996-03-01

    One of the activities of the PNL Vitrification Technology Development (PVTD) Project is to assist the Tank Waste Remediation Systems (TWRS) Program in determining which melter systems should be performance tested for potential implementation in the high-level waste (HLW) vitrification plant. The Richland Operations Office (RL) has recommended that the Cold Crucible Melter (CCM) be evaluated as a candidate ``next generation`` melter. As a result, the CCM System Evaluation cost account was established under the PVTD Project so that the CCM could be initially assessed on a high-priority basis. This letter report summarizes a brief initial review and assessment of the CCM. Using the recommendations made in this document, Westinghouse Hanford Company (WHC) and RL will make a decision regarding the urgency of performance testing the CCM. If the decision is favorable, a subcontract will be negotiated for performance testing of a CCM using Hanford HLW simulants in a pilot-scale facility. Because of the aggressive nature of the schedule, the CCM evaluation was not rigorous. The evaluation consisted of a literature review and interviews with proponents of the technology during a recent trip to France. This letter report summarizes the evaluation and makes recommendations regarding further work in this area.

  1. Insights from letter position dyslexia on morphological decomposition in reading.

    PubMed

    Friedmann, Naama; Gvion, Aviah; Nisim, Roni

    2015-01-01

    We explored morphological decomposition in reading, the locus in the reading process in which it takes place and its nature, comparing different types of morphemes. We assessed these questions through the analysis of letter position errors in readers with letter position dyslexia (LPD). LPD is a selective impairment to letter position encoding in the early stage of word reading, which results in letter migrations (such as reading "cloud" for "could"). We used the fact that migrations in LPD occur mainly in word-interior letters, whereas exterior letters rarely migrate. The rationale was that if morphological decomposition occurs prior to letter position encoding and strips off affixes, word-interior letters adjacent to an affix (e.g., signs-signs) would become exterior following affix-stripping and hence exhibit fewer migrations. We tested 11 Hebrew readers with developmental LPD and 1 with acquired LPD in 6 experiments of reading aloud, lexical decision, and comprehension, at the single word and sentence levels (compared with 25 age-matched control participants). The LPD participants read a total of 12,496 migratable words. We examined migrations next to inflectional, derivational, or bound function morphemes compared with migrations of exterior letters. The results were that root letters adjacent to inflectional and derivational morphemes were treated like middle letters, and migrated frequently, whereas root letters adjacent to bound function morphemes patterned with exterior letters, and almost never migrated. Given that LPD is a pre-lexical deficit, these results indicate that morphological decomposition takes place in an early, pre-lexical stage. The finding that morphologically complex nonwords showed the same patterns indicates that this decomposition is structurally, rather than lexically, driven. We suggest that letter position encoding takes place before morphological analysis, but in some cases, as with bound function morphemes, the complex word is re

  2. Insights from letter position dyslexia on morphological decomposition in reading

    PubMed Central

    Friedmann, Naama; Gvion, Aviah; Nisim, Roni

    2015-01-01

    We explored morphological decomposition in reading, the locus in the reading process in which it takes place and its nature, comparing different types of morphemes. We assessed these questions through the analysis of letter position errors in readers with letter position dyslexia (LPD). LPD is a selective impairment to letter position encoding in the early stage of word reading, which results in letter migrations (such as reading “cloud” for “could”). We used the fact that migrations in LPD occur mainly in word-interior letters, whereas exterior letters rarely migrate. The rationale was that if morphological decomposition occurs prior to letter position encoding and strips off affixes, word-interior letters adjacent to an affix (e.g., signs-signs) would become exterior following affix-stripping and hence exhibit fewer migrations. We tested 11 Hebrew readers with developmental LPD and 1 with acquired LPD in 6 experiments of reading aloud, lexical decision, and comprehension, at the single word and sentence levels (compared with 25 age-matched control participants). The LPD participants read a total of 12,496 migratable words. We examined migrations next to inflectional, derivational, or bound function morphemes compared with migrations of exterior letters. The results were that root letters adjacent to inflectional and derivational morphemes were treated like middle letters, and migrated frequently, whereas root letters adjacent to bound function morphemes patterned with exterior letters, and almost never migrated. Given that LPD is a pre-lexical deficit, these results indicate that morphological decomposition takes place in an early, pre-lexical stage. The finding that morphologically complex nonwords showed the same patterns indicates that this decomposition is structurally, rather than lexically, driven. We suggest that letter position encoding takes place before morphological analysis, but in some cases, as with bound function morphemes, the complex word

  3. A Roman correspondence: George Ent and Cassiano dal Pozzo, 1637-55.

    PubMed

    Cook, Alan

    2005-01-22

    George Ent (FRS 1663), a distinguish physician, was in Rome in 1636, visited the notable collector Cassiano dal Pozzo and saw his Paper Museum. After he returned to London he carried on a correspondence with Cassiano in letters of more than ordinary interest. Cassiano had sent Ent specimens of fossil wood and a table made from fossil wood. They had come from the estates at Acquasparta belonging to Prince Federico Cesi, the founder of the Accademia dei Lincie. The specimens and the table were shown to early meetings of The Royal Society and had a significant part in the developing debate on the origin of fossils. The letters also record exchanges of books between London and Rome. Among medical matters there is news of William Harvey and his works.

  4. From numbers to letters: feedback regularization in visual word recognition.

    PubMed

    Molinaro, Nicola; Duñabeitia, Jon Andoni; Marìn-Gutièrrez, Alejandro; Carreiras, Manuel

    2010-04-01

    Word reading in alphabetic languages involves letter identification, independently of the format in which these letters are written. This process of letter 'regularization' is sensitive to word context, leading to the recognition of a word even when numbers that resemble letters are inserted among other real letters (e.g., M4TERI4L). The present study investigates the electrophysiological correlates of number-to-letter regularization by means of the masked priming paradigm: target words (MATERIAL) were preceded by fully alphabetic primes (MATERIAL), primes with letter-like numbers (M4T3R14L), or primes with unrelated numbers (M7T6R28L). ERPs revealed three subsequent effects. Around 150 ms the unrelated numbers condition elicited a positive effect, compared to the other two conditions, in the occipital electrodes. Then, target words preceded by primes with numbers elicited a more negative N200 in the same electrodes compared to the fully alphabetic condition. Finally, both alphabetic primes and letter-like numbers elicited a posterior positive component peaking around 260 ms compared to unrelated numbers. Source analysis for each electrophysiological effect revealed a similar early increase of activity in the left occipito-temporal pathway for alphabetic primes and primes with letter-like numbers. Around 200 ms, the orthographic interference due to the numerical values correlated with an increase of activity in parietal areas; finally, a recursive effect in the left occipital cortex was found, reflecting abstract letter activation. These results indicate that direct feedback interaction from word units strongly influences the activation of the letter units at a format-independent abstract level.

  5. NEESPI focus issues in Environmental Research Letters

    NASA Astrophysics Data System (ADS)

    Norman, Julian; Groisman, Pavel; Soja, Amber J.

    2010-05-01

    In 2007 and 2009 Environmental Research Letters published focus issues (edited by Pavel Groisman and Amber J Soja) made up of work carried out by NEESPI participants. Here, we present the content of those focus issues as an invaluable resource for researchers working in the NEESPI study area. The first of the two issues, published in 2007 with title 'Northern Hemisphere High Latitude Climate and Environmental Change', presents a diverse collection of articles that are assembled into five groups devoted to studies of climate and hydrology, land cover and land use, the biogeochemical cycle and its feedbacks, the cryosphere, and human dimensions. The second issue, published in 2009, with title 'Climatic and Environmental Change in Northern Eurasia' presents diverse, assorted studies of different aspects of contemporary change, representing the diversity of climates and ecosystems across Northern Eurasia.

  6. Boscovich: scientist and man of letters

    NASA Astrophysics Data System (ADS)

    Proverbio, E.

    Ruggiero Giuseppe Boscovich (1711-1781) is known as one of the most important scientists of the second half of XVIII century, but he was active also as a man of letters, especially through an abundant production of poems in Latin verse. We try to interpret these two, apparently antinomic, aspects of his character in the framework of the culture of his epoch, in which science and literary productions were not considered as two separate or opposite fields, but only two different aspects of human knowledge. In particular we review the field of his poetic production in which this fundamental unity of knowledge is most evident, namely his poems with didactic-scientific subjects, which are examples of high-level popularization of the latest progresses in science (in particular astronomy and Newtonian physics) by means of elegant Latin verse.

  7. Cultural Framing: Foreign Correspondents and Their Work.

    ERIC Educational Resources Information Center

    Starck, Kenneth; Villanueva, Estela

    With the notion of cultural framing as a theoretical backdrop, a study examined the role of culture in the work of foreign correspondents. The aim was to explore cultural aspects of international news reporting that may suggest avenues for more systematic inquiry into the role of culture in the work of the foreign correspondent. Of 75 examined…

  8. 32 CFR 845.11 - Correspondence.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 6 2013-07-01 2013-07-01 false Correspondence. 845.11 Section 845.11 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE CLAIMS AND LITIGATION COUNSEL FEES AND OTHER EXPENSES IN FOREIGN TRIBUNALS § 845.11 Correspondence. Judge advocates who advise...

  9. 32 CFR 845.11 - Correspondence.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 6 2011-07-01 2011-07-01 false Correspondence. 845.11 Section 845.11 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE CLAIMS AND LITIGATION COUNSEL FEES AND OTHER EXPENSES IN FOREIGN TRIBUNALS § 845.11 Correspondence. Judge advocates who advise...

  10. 32 CFR 845.11 - Correspondence.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 6 2014-07-01 2014-07-01 false Correspondence. 845.11 Section 845.11 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE CLAIMS AND LITIGATION COUNSEL FEES AND OTHER EXPENSES IN FOREIGN TRIBUNALS § 845.11 Correspondence. Judge advocates who advise...

  11. 32 CFR 845.11 - Correspondence.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 6 2010-07-01 2010-07-01 false Correspondence. 845.11 Section 845.11 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE CLAIMS AND LITIGATION COUNSEL FEES AND OTHER EXPENSES IN FOREIGN TRIBUNALS § 845.11 Correspondence. Judge advocates who advise...

  12. 32 CFR 845.11 - Correspondence.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 6 2012-07-01 2012-07-01 false Correspondence. 845.11 Section 845.11 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE CLAIMS AND LITIGATION COUNSEL FEES AND OTHER EXPENSES IN FOREIGN TRIBUNALS § 845.11 Correspondence. Judge advocates who advise...

  13. Computer Networking with the Victorian Correspondence School.

    ERIC Educational Resources Information Center

    Conboy, Ian

    During 1985 the Education Department installed two-way radios in 44 remote secondary schools in Victoria, Australia, to improve turn-around time for correspondence assignments. Subsequently, teacher supervisors at Melbourne's Correspondence School sought ways to further augument audio interactivity with computer networking. Computer equipment was…

  14. Teaching by Correspondence. UNESCO Source Book.

    ERIC Educational Resources Information Center

    Erdos, Renee F.

    This resource book contains practical advice on all aspects of correspondence study, contributed by countries in which correspondence teaching has become an integral adjunct to the regular educational system. Included are discussions of school organization; writing, editing, and correction of studies; cost of production of materials; school…

  15. The correspondence between Winkler and Monakow during World War I.

    PubMed

    Koehler, Peter J; Jagella, Caroline

    2015-01-01

    The correspondence (1907-1930) between two leading European neurologists, Cornelis Winkler (1855-1941) and Constantin von Monakow (1853-1930), has been preserved in Amsterdam and Zurich. For this paper, letters exchanged during World War I were studied. Professional as well as personal issues were discussed. An international neurology meeting in Berne in September 1914 had to be cancelled due to the war. They hoped that (neuro)scientists would remain politically neutral, continue scientific cooperation, and even be able to influence the course of the war. Winkler and Monakow tried to continue their work on the International Brain Atlas. Although living in neutral countries (The Netherlands and Switzerland), they observed that their practice and scientific work suffered from war conditions. While Winkler continued his activities as a neurologist, Monakow, affected emotionally, experienced a change in scientific interest toward psychoneurology. He used his diaschisis concept, originally an explanation for transient phenomena in stroke, as a metaphor for the social and cultural effects of the war. He directly related cultural development and brain science, bringing in his own emotions, which resulted in the first of several publications on the relations between biology, brain science, and culture.

  16. Groupwise surface correspondence using particle filtering

    NASA Astrophysics Data System (ADS)

    Li, Guangxu; Kim, Hyoungseop; Tan, Joo Kooi; Ishikawa, Seiji

    2015-03-01

    To obtain an effective interpretation of organic shape using statistical shape models (SSMs), the correspondence of the landmarks through all the training samples is the most challenging part in model building. In this study, a coarse-tofine groupwise correspondence method for 3-D polygonal surfaces is proposed. We manipulate a reference model in advance. Then all the training samples are mapped to a unified spherical parameter space. According to the positions of landmarks of the reference model, the candidate regions for correspondence are chosen. Finally we refine the perceptually correct correspondences between landmarks using particle filter algorithm, where the likelihood of local surface features are introduced as the criterion. The proposed method was performed on the correspondence of 9 cases of left lung training samples. Experimental results show the proposed method is flexible and under-constrained.

  17. Feelings...the Way to Better Letter Writing.

    ERIC Educational Resources Information Center

    Memphis State Univ., TN. Early Childhood Education Center.

    This booklet provides guidelines to produce effective, responsive business letter writing, which promotes public relations, gives plain answers to questions, clearly states requests for additional information, and increases office efficiency and economy. Four major characteristics of such letters are discussed: (1) brevity and the avoidance of…

  18. 14 CFR 136.3 - Letters of Authorization.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...) AIR CARRIERS AND OPERATORS FOR COMPENSATION OR HIRE: CERTIFICATION AND OPERATIONS COMMERCIAL AIR TOURS AND NATIONAL PARKS AIR TOUR MANAGEMENT National Air Tour Safety Standards § 136.3 Letters of Authorization. Operators subject to this subpart who have Letters of Authorization may use the...

  19. Editorial: acceptance criteria and editorial procedures for Optics Letters.

    PubMed

    Zhang, Xi-Cheng; Andersen, Peter E; Justus, Brian L; Galtarossa, Andrea

    2014-09-01

    Optics Letters Editors strive to provide timely reviews and decisions for authors while bringing top quality papers to the optics community. The purpose of this editorial is to explain Optics Letters' acceptance criteria and editorial procedures. Our hope is that greater transparency concerning the decision-making process will increase understanding as well as acceptance of our criteria and procedures.

  20. 50 CFR 216.178 - Renewal of Letters of Authorization.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 10 2012-10-01 2012-10-01 false Renewal of Letters of Authorization. 216.178 Section 216.178 Wildlife and Fisheries NATIONAL MARINE FISHERIES SERVICE, NATIONAL OCEANIC AND... comment on renewals of Letters of Authorization are restricted to: (1) New cited information and...