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Stefan Knecht

Bio: Stefan Knecht is an academic researcher from ETH Zurich. The author has contributed to research in topics: Density functional theory & Lateralization of brain function. The author has an hindex of 74, co-authored 277 publications receiving 19979 citations. Previous affiliations of Stefan Knecht include University of Düsseldorf & University of Strasbourg.


Papers
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Journal ArticleDOI
08 Jun 1995-Nature
TL;DR: A very strong direct relationship is reported between the amount of cortical reorganization and the magnitude of phantom limb pain (but not non-painful phantom phenomena) experienced after arm amputation, indicating that phantom-limb pain is related to, and may be a consequence of, plastic changes in primary somatosensory cortex.
Abstract: Although phantom-limb pain is a frequent consequence of the amputation of an extremity, little is known about its origin. On the basis of the demonstration of substantial plasticity of the somatosensory cortex after amputation or somatosensory deafferentation in adult monkeys, it has been suggested that cortical reorganization could account for some non-painful phantom-limb phenomena in amputees and that cortical reorganization has an adaptive (that is, pain-preventing) function. Theoretical and empirical work on chronic back pain has revealed a positive relationship between the amount of cortical alteration and the magnitude of pain, so we predicted that cortical reorganization and phantom-limb pain should be positively related. Using non-invasive neuromagnetic imaging techniques to determine cortical reorganization in humans, we report a very strong direct relationship (r = 0.93) between the amount of cortical reorganization and the magnitude of phantom limb pain (but not non-painful phantom phenomena) experienced after arm amputation. These data indicate that phantom-limb pain is related to, and may be a consequence of, plastic changes in primary somatosensory cortex.

1,692 citations

Journal ArticleDOI
01 Dec 2000-Brain
TL;DR: The results clearly demonstrate that the relationship between handedness and language dominance is not an artefact of cerebral pathology but a natural phenomenon.
Abstract: In most people the left hemisphere of the brain is dominant for language. Because of the increased incidence of atypical right-hemispheric language in left-handed neurological patients, a systematic association between handedness and dominance has long been suspected. To clarify the relationship between handedness and language dominance in healthy subjects, we measured lateralization directly by functional transcranial Doppler sonography in 326 healthy individuals using a word-generation task. The incidence of right-hemisphere language dominance was found to increase linearly with the degree of left-handedness, from 4% in strong right-handers (handedness = 100) to 15% in ambidextrous individuals and 27% in strong left-handers (handedness = -100). The relationship could be approximated by the formula: f1.gif" BORDER="0">. These results clearly demonstrate that the relationship between handedness and language dominance is not an artefact of cerebral pathology but a natural phenomenon.

1,370 citations

Journal ArticleDOI
Kestutis Aidas1, Celestino Angeli2, Keld L. Bak3, Vebjørn Bakken4, Radovan Bast5, Linus Boman6, Ove Christiansen3, Renzo Cimiraglia2, Sonja Coriani7, Pål Dahle8, Erik K. Dalskov, Ulf Ekström4, Thomas Enevoldsen9, Janus J. Eriksen3, Patrick Ettenhuber3, Berta Fernández10, Lara Ferrighi, Heike Fliegl4, Luca Frediani, Kasper Hald11, Asger Halkier, Christof Hättig12, Hanne Heiberg13, Trygve Helgaker4, Alf C. Hennum14, Hinne Hettema15, Eirik Hjertenæs16, Stine Høst3, Ida-Marie Høyvik3, Maria Francesca Iozzi17, Brannislav Jansik18, Hans-Jørgen Aa. Jensen9, Dan Jonsson, Poul Jørgensen3, Johanna Kauczor19, Sheela Kirpekar, Thomas Kjærgaard3, Wim Klopper20, Stefan Knecht21, Rika Kobayashi22, Henrik Koch16, Jacob Kongsted9, Andreas Krapp, Kasper Kristensen3, Andrea Ligabue23, Ola B. Lutnæs24, Juan Ignacio Melo25, Kurt V. Mikkelsen26, Rolf H. Myhre16, Christian Neiss27, Christian B. Nielsen, Patrick Norman19, Jeppe Olsen3, Jógvan Magnus Haugaard Olsen9, Anders Osted, Martin J. Packer9, Filip Pawłowski28, Thomas Bondo Pedersen4, Patricio Federico Provasi29, Simen Reine4, Zilvinas Rinkevicius5, Torgeir A. Ruden, Kenneth Ruud, Vladimir V. Rybkin20, Paweł Sałek, Claire C. M. Samson20, Alfredo Sánchez de Merás30, Trond Saue31, Stephan P. A. Sauer26, Bernd Schimmelpfennig20, Kristian Sneskov11, Arnfinn Hykkerud Steindal, Kristian O. Sylvester-Hvid, Peter R. Taylor32, Andrew M. Teale33, Erik I. Tellgren4, David P. Tew34, Andreas J. Thorvaldsen3, Lea Thøgersen35, Olav Vahtras5, Mark A. Watson36, David J. D. Wilson37, Marcin Ziółkowski38, Hans Ågren5 
TL;DR: Dalton is a powerful general‐purpose program system for the study of molecular electronic structure at the Hartree–Fock, Kohn–Sham, multiconfigurational self‐consistent‐field, Møller–Plesset, configuration‐interaction, and coupled‐cluster levels of theory.
Abstract: Dalton is a powerful general-purpose program system for the study of molecular electronic structure at the Hartree-Fock, Kohn-Sham, multiconfigurational self-consistent-field, MOller-Plesset, confi ...

1,212 citations

Journal ArticleDOI
TL;DR: BDNF and two of the catecholamines seem to be mediators by which physical exercise improves learning, and vocabulary learning was 20 percent faster after intense physical exercise as compared to the other two conditions.

702 citations

Journal ArticleDOI
TL;DR: The OpenMolcas environment is described and features unique to simulations of spectroscopic and magnetic phenomena such as the exact semiclassical description of the interaction between light and matter, various X-ray processes, magnetic circular dichroism and properties are described.
Abstract: In this Article we describe the OpenMolcas environment and invite the computational chemistry community to collaborate. The open-source project already includes a large number of new developments realized during the transition from the commercial MOLCAS product to the open-source platform. The paper initially describes the technical details of the new software development platform. This is followed by brief presentations of many new methods, implementations, and features of the OpenMolcas program suite. These developments include novel wave function methods such as stochastic complete active space self-consistent field, density matrix renormalization group (DMRG) methods, and hybrid multiconfigurational wave function and density functional theory models. Some of these implementations include an array of additional options and functionalities. The paper proceeds and describes developments related to explorations of potential energy surfaces. Here we present methods for the optimization of conical intersections, the simulation of adiabatic and nonadiabatic molecular dynamics, and interfaces to tools for semiclassical and quantum mechanical nuclear dynamics. Furthermore, the Article describes features unique to simulations of spectroscopic and magnetic phenomena such as the exact semiclassical description of the interaction between light and matter, various X-ray processes, magnetic circular dichroism, and properties. Finally, the paper describes a number of built-in and add-on features to support the OpenMolcas platform with postcalculation analysis and visualization, a multiscale simulation option using frozen-density embedding theory, and new electronic and muonic basis sets.

559 citations


Cited by
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Journal ArticleDOI
06 Jun 1986-JAMA
TL;DR: The editors have done a masterful job of weaving together the biologic, the behavioral, and the clinical sciences into a single tapestry in which everyone from the molecular biologist to the practicing psychiatrist can find and appreciate his or her own research.
Abstract: I have developed "tennis elbow" from lugging this book around the past four weeks, but it is worth the pain, the effort, and the aspirin. It is also worth the (relatively speaking) bargain price. Including appendixes, this book contains 894 pages of text. The entire panorama of the neural sciences is surveyed and examined, and it is comprehensive in its scope, from genomes to social behaviors. The editors explicitly state that the book is designed as "an introductory text for students of biology, behavior, and medicine," but it is hard to imagine any audience, interested in any fragment of neuroscience at any level of sophistication, that would not enjoy this book. The editors have done a masterful job of weaving together the biologic, the behavioral, and the clinical sciences into a single tapestry in which everyone from the molecular biologist to the practicing psychiatrist can find and appreciate his or

7,563 citations

Journal ArticleDOI
TL;DR: The recommended quantity and quality of exercise for developing and maintaining Cardiorespiratory and Muscular Fitness, and Flexibility in healthy adults is discussed in the position stand of the American College of Sports Medicine (ACSM) Position Stand.
Abstract: The purpose of this Position Stand is to provide guidance to professionals who counsel and prescribe individualized exercise to apparently healthy adults of all ages. These recommendations also may apply to adults with certain chronic diseases or disabilities, when appropriately evaluated and advised by a health professional. This document supersedes the 1998 American College of Sports Medicine (ACSM) Position Stand, "The Recommended Quantity and Quality of Exercise for Developing and Maintaining Cardiorespiratory and Muscular Fitness, and Flexibility in Healthy Adults." The scientific evidence demonstrating the beneficial effects of exercise is indisputable, and the benefits of exercise far outweigh the risks in most adults. A program of regular exercise that includes cardiorespiratory, resistance, flexibility, and neuromotor exercise training beyond activities of daily living to improve and maintain physical fitness and health is essential for most adults. The ACSM recommends that most adults engage in moderate-intensity cardiorespiratory exercise training for ≥30 min·d on ≥5 d·wk for a total of ≥150 min·wk, vigorous-intensity cardiorespiratory exercise training for ≥20 min·d on ≥3 d·wk (≥75 min·wk), or a combination of moderate- and vigorous-intensity exercise to achieve a total energy expenditure of ≥500-1000 MET·min·wk. On 2-3 d·wk, adults should also perform resistance exercises for each of the major muscle groups, and neuromotor exercise involving balance, agility, and coordination. Crucial to maintaining joint range of movement, completing a series of flexibility exercises for each the major muscle-tendon groups (a total of 60 s per exercise) on ≥2 d·wk is recommended. The exercise program should be modified according to an individual's habitual physical activity, physical function, health status, exercise responses, and stated goals. Adults who are unable or unwilling to meet the exercise targets outlined here still can benefit from engaging in amounts of exercise less than recommended. In addition to exercising regularly, there are health benefits in concurrently reducing total time engaged in sedentary pursuits and also by interspersing frequent, short bouts of standing and physical activity between periods of sedentary activity, even in physically active adults. Behaviorally based exercise interventions, the use of behavior change strategies, supervision by an experienced fitness instructor, and exercise that is pleasant and enjoyable can improve adoption and adherence to prescribed exercise programs. Educating adults about and screening for signs and symptoms of CHD and gradual progression of exercise intensity and volume may reduce the risks of exercise. Consultations with a medical professional and diagnostic exercise testing for CHD are useful when clinically indicated but are not recommended for universal screening to enhance the safety of exercise.

7,223 citations

Journal ArticleDOI
TL;DR: Estimates of expected health outcomes for larger societies are included, where data exist, and the level of evidence and the strength of recommendation of particular treatment options are weighed and graded according to pre-defined scales.
Abstract: Guidelines summarize and evaluate all currently available evidence on a particular issue with the aim of assisting physicians in selecting the best management strategy for an individual patient suffering from a given condition, taking into account the impact on outcome, as well as the risk–benefit ratio of particular diagnostic or therapeutic means. Guidelines are no substitutes for textbooks. The legal implications of medical guidelines have been discussed previously. A large number of Guidelines have been issued in recent years by the European Society of Cardiology (ESC) as well as by other societies and organizations. Because of the impact on clinical practice, quality criteria for development of guidelines have been established in order to make all decisions transparent to the user. The recommendations for formulating and issuing ESC Guidelines can be found on the ESC Web Site (http://www.escardio.org/guidelines-surveys/esc-guidelines/about/Pages/rules-writing.aspx). In brief, experts in the field are selected and undertake a comprehensive review of the published evidence for management and/or prevention of a given condition. A critical evaluation of diagnostic and therapeutic procedures is performed, including assessment of the risk–benefit ratio. Estimates of expected health outcomes for larger societies are included, where data exist. The level of evidence and the strength of recommendation of particular treatment options are weighed and graded according to pre-defined scales, as outlined in Tables 1 and 2 . View this table: Table 1 Classes of recommendations View this table: Table 2 Levels of evidence The experts of the writing panels have provided disclosure statements of all relationships they may have that might be perceived as real or potential sources of conflicts of interest. These disclosure forms are kept on file at the European Heart House, headquarters of the ESC. Any changes in conflict of interest that arise during the writing period must be notified to the ESC. The Task Force report received its entire financial support from …

5,329 citations

Journal ArticleDOI
01 Nov 2016-Europace
TL;DR: The Task Force for the management of atrial fibrillation of the European Society of Cardiology has been endorsed by the European Stroke Organisation (ESO).
Abstract: The Task Force for the management of atrial fibrillation of the European Society of Cardiology (ESC) Developed with the special contribution of the European Heart Rhythm Association (EHRA) of the ESC Endorsed by the European Stroke Organisation (ESO)

5,255 citations