Search results for " groups"
showing 10 items of 1018 documents
1-(v,3,r) designs and the equation x+y+z=0 in finite abelian groups
2009
Let (G, +) be a finite abelian group with more than three elements and let B_3 be the family of all the unordered triples {x,y,z} of distinct elements of G such that x+y+z=0. We show that (G, B_3) is a 1-(v,3,r) design if and only if G is either an elementary abelian 3-group or the direct sum of Z/2Z with an elementary abelian 3-group. We also characterize the groups containing at least an element that does not belong to any triple in B_3
Magic informationally complete POVMs with permutations
2017
Eigenstates of permutation gates are either stabilizer states (for gates in the Pauli group) or magic states, thus allowing universal quantum computation [M. Planat and Rukhsan-Ul-Haq, Preprint 1701.06443]. We show in this paper that a subset of such magic states, when acting on the generalized Pauli group, define (asymmetric) informationally complete POVMs. Such IC-POVMs, investigated in dimensions $2$ to $12$, exhibit simple finite geometries in their projector products and, for dimensions $4$ and $8$ and $9$, relate to two-qubit, three-qubit and two-qutrit contextuality.
Increase in finishers and improvement of performance of masters runners in the Marathon des Sables
2013
Saskia Carolin Jampen,1 Beat Knechtle,1,2 Christoph Alexander Rüst,1 Romuald Lepers,3 Thomas Rosemann11Institute of General Practice and for Health Services Research, University of Zurich, Zurich, Switzerland; 2Gesundheitszentrum St Gallen, St Gallen, Switzerland; 3INSERM U1093, Faculty of Sport Sciences, University of Burgundy, Dijon, FranceAim: The aim of the study was to examine finisher and performance trends of ultrarunners in the Marathon des Sables, the world's largest multistage ultramarathon.Methods: The age and running speed was analyzed for 6945 finishes of 909 women and 6036 men between 2003 and 2012 at the Marathon des Sables covering about 240 km in the Morocc…
Differences in Participation and Performance Trends in Age Group Half and Full Marathoners
2014
International audience; Recent studies investigated participation and performance trends in age group half marathoners and full marathoners for a single event. The present study investigated participation and performance trends in age group athletes in all half marathons and full marathons held in a single country during a given period of time. Changes in running performance and age of 226,754 half marathoners and 86,419 full marathoners competing in Switzerland between 2000 and 2010 were analyzed using linear regression analyses. The number of half marathoners increased (P < 0.01) from 2000 to 2010 for both men (+231%) and women (+299%). In contrast, the number of male and female full mara…
Master runners dominate 24-h ultramarathons worldwide—a retrospective data analysis from 1998 to 2011
2013
Abstract Background The aims of the present study were to examine (a) participation and performance trends and (b) the age of peak running performance in master athletes competing in 24-h ultra-marathons held worldwide between 1998 and 2011. Methods Changes in both running speed and the age of peak running speed in 24-h master ultra-marathoners (39,664 finishers, including 8,013 women and 31,651 men) were analyzed. Results The number of 24-h ultra-marathoners increased for both women and men across years (P < 0.01). The age of the annual fastest woman decreased from 48 years in 1998 to 35 years in 2011. The age of peaking running speed remained unchanged across time at 42.5 ± 5.2 years f…
Finisher and performance trends in female and male mountain ultramarathoners by age group
2013
Christoph Alexander R&uuml;st,1 Beat Knechtle,1,2 Evelyn Eichenberger,1 Thomas Rosemann,1 Romuald Lepers31Institute of General Practice and for Health Services Research, University of Zurich, Zurich, 2Gesundheitszentrum St Gallen, St Gallen, Switzerland; 3French Institute of Health and Medical Research, Faculty of Sport Sciences, University of Burgundy, Dijon, FranceBackground: This study examined changes according to age group in the number of finishers and running times for athletes in female and male mountain ultramarathoners competing in the 78 km Swiss Alpine Marathon, the largest mountain ultramarathon in Europe and held in high alpine terrain.Methods: The association between age …
Analysis of participation and performance in athletes by age group in ultramarathons of more than 200 km in length
2013
Matthias Zingg,1 Beat Knechtle,1,2 Christoph A R&uuml;st,1 Thomas Rosemann,1 Romuald Lepers3 1Institute of General Practice and Health Services Research, University of Zurich, Zurich, Switzerland; 2Gesundheitszentrum St Gallen, St Gallen, Switzerland; 3INSERM U1093, Faculty of Sport Sciences, University of Burgundy, Dijon, France Background: Participation and performance trends for athletes by age group have been investigated for marathoners and ultramarathoners competing in races up to 161 km, but not for longer distances of more than 200 km. Methods: Participation and performance trends in athletes by age group in the Badwater (217 km) and Spartathlon (246 km) races were compared from…
On presentations for mapping class groups of orientable surfaces via Poincaré's Polyhedron theorem and graphs of groups
2021
The mapping class group of an orientable surface with one boundary component, S, is isomorphic to a subgroup of the automorphism group of the fundamental group of S. We call these subgroups algebraic mapping class groups. An algebraic mapping class group acts on a space called ordered Auter space. We apply Poincaré's Polyhedron theorem to this action. We describe a decomposition of ordered Auter space. From these results, we deduce that the algebraic mapping class group of S is a quotient of the fundamental group of a graph of groups with, at most, two vertices and, at most, six edges. Vertex and edge groups of our graph of groups are mapping class groups of orientable surfaces with one, tw…
„Wir wussten, dass es schwierig wird, doch damit haben wir nicht gerechnet!“ Erfahrungen beim Studieneinschluss von Krebspatient*innen mit Migrations…
2021
Zusammenfassung Hintergrund Der Prozess des Studieneinschlusses von Teilnehmenden ist ein wichtiger Bestandteil und oftmals aufwendiger Arbeitsschritt in wissenschaftlichen Forschungsprojekten. Aufgrund unterschiedlicher finanzieller, organisatorischer und ethischer Rahmenbedingungen stellt die fristgerechte Gewinnung von Teilnehmenden haufig eine Herausforderung dar. In diesem Beitrag berichten wir uber unsere Erfahrungen hinsichtlich des Studieneinschlusses, die wir im Projekt „Psychoonkologische Versorgung von Krebspatienten mit Migrationshintergrund – eine Mixed-Methods-Studie“ (POM) gemacht haben. Methode Die Gewinnung von Teilnehmenden erfolgte uber ambulante hamato-onkologische Schwe…
Automorphisms of 2–dimensional right-angled Artin groups
2007
We study the outer automorphism group of a right-angled Artin group AA in the case where the defining graph A is connected and triangle-free. We give an algebraic description of Out.AA/ in terms of maximal join subgraphs in A and prove that the Tits’ alternative holds for Out.AA/. We construct an analogue of outer space for Out.AA/ and prove that it is finite dimensional, contractible, and has a proper action of Out.AA/. We show that Out.AA/ has finite virtual cohomological dimension, give upper and lower bounds on this dimension and construct a spine for outer space realizing the most general upper bound. 20F36; 20F65, 20F28