1,172 research outputs found
Wellenspiel : Dancing Wavelets
https://digitalcommons.library.umaine.edu/mmb-ps/1708/thumbnail.jp
The Essence of Philosophy
Wilhelm Dilthey (1833-1911), the great German humanist, remained a towering figure in Europe long into the twentieth century. Published in 1954, this translation by Stephen A. Emery and William T. Emery was the first English translation of Dilthey's "Das Wesen der Philosophie" (1907) as well as his first work to be translated completely into English, making Dilthey accessible to scholars of the English-speaking world
Stripes: Why hole rich lines are antiphase domain walls?
For stripes of hole rich lines in doped antiferromagnets, we investigate the
competition between anti-phase and in-phase domain wall ground state
configurations. We argue that a phase transition must occure as a function of
the electron/hole filling fraction of the domain wall. Due to {\em transverse}
kinetic hole fluctuations, empty domain walls are always anti-phase. At
arbitrary electron filling fraction () of the domain wall (and in
particular for as in LaNdSrCuO), it is essential to
account also for the transverse magnetic interactions of the electrons and
their mobility {\em along} the domain wall.
We find that the transition from anti-phase to in-phase stripe domain wall
occurs at a critical filling fraction , for any value of
. We further use our model to estimate the spin-wave
velocity in a stripe system. Finally, relate the results of our microscopic
model to previous Landau theory approach to stripes.Comment: 11 pages, 3 figure
Higher Rates of Head Contacts, Body Checking, and Suspected Injuries in Ringette Than Female Ice Hockey:Time to Ring in Opportunities for Prevention
Objective: Ringette is a popular team ice sport in Canada, primarily played by females. Bodychecking is prohibited at all levels of play. This study used video-analysis to evaluate physical contact (PC), head contact (HC), and suspected injury and concussion incidence rates (IR) in youth ringette. Study Design: Cross-sectional. Subjects: Youth ringette players from the 2021-2022 season playing in the U16 (ages 14-15) or U19 (ages 16-18) age groups (A or AA levels). Games were filmed from regular season, provincials, and nationals (AA only). Observation Technique: Game video-recordings were analyzed using Dartfish video-analysis software. Validated criteria were used to assess trunk PC intensity (levels 1-3=lower-intensity PC, levels 4-5=higher-intensity bodychecking), HC type (HC1=direct player-to-player, HC2=indirect), suspected injury (concussion, non-concussion), and penalty enforcement. Outcome Measures: Multivariable Poisson regression analyses (adjusted for cluster by teamgame, offset by game-minutes) were used to estimate PC, HC, and suspected injury and concussion IRs. Incidence rate ratios (IRR) were used to compare IR across age groups, levels of play, and game types. Proportions of bodychecks and HC1s penalized were reported. Results: Seventy-eight team-games were included (U16 n=40, U19 n=38; A n=30, AA n=48; regular season n=30, provincials n=32, nationals n=16). The overall bodychecking IR was 17.34/100 team-minutes (95% CI:14.80-20.33), HC 19.09/100 team-minutes (95% CI:16.7421.78), suspected injury 1.53/100 team-minutes (95% CI:1.13-2.09), and suspected concussion 0.74/100 team-minutes (95% CI:0.48-1.13). Only 29% (95% CI:24.97-32.59) of bodychecks and 7% (95% CI:4.76-9.70) of HC1s were penalized. No differences were found in bodychecking, HCs, or suspected injury and concussion IRs between age groups or levels of play. Bodychecking IRs were 64% (IRR=1.64; 95% CI:1.13-2.39) higher in provincials and 24% (IRR=1.24; 95% CI:1.02-1.50) higher in nationals than regular season games. A 31% (IRR=0.69; 95% CI:0.49-0.97) lower rate of HCs was reported in national games compared to provincial games. Bodychecking was the most common mechanism for concussion (70%) and nonconcussion injuries (67%), with concussions most often associated with HC2s (62.5%). Conclusions: Bodychecking and HC1 IRs were high among youth ringette players, despite rules prohibiting them. Future research should target prevention strategies aimed to reduce HC1s and bodychecking to reduce injury and concussion IRs in youth ringette
High rates of bodychecking, head conatcts, and suspected injuries found in youth ringette through video analysis.
Objective: Ringette is a popular team ice sport in Canada, primarily played by females. Bodychecking is prohibited at all levels of play. This study used video-analysis to evaluate physical contact (PC), head contact (HC), and suspected injury and concussion incidence rates (IR) in youth ringette. Study Design: Cross-sectional. Subjects: Youth ringette players from the 2021-2022 season playing in the U16 (ages 14-15) or U19 (ages 16-18) age groups (A or AA levels). Games were filmed from regular season, provincials, and nationals (AA only). Observation Technique: Game video-recordings were analyzed using Dartfish video-analysis software. Validated criteria were used to assess trunk PC intensity (levels 1-3=lower-intensity PC, levels 4-5=higher-intensity bodychecking), HC type (HC1=direct player-to-player, HC2=indirect), suspected injury (concussion, non-concussion), and penalty enforcement. Outcome Measures: Multivariable Poisson regression analyses (adjusted for cluster by teamgame, offset by game-minutes) were used to estimate PC, HC, and suspected injury and concussion IRs. Incidence rate ratios (IRR) were used to compare IR across age groups, levels of play, and game types. Proportions of bodychecks and HC1s penalized were reported. Results: Seventy-eight team-games were included (U16 n=40, U19 n=38; A n=30, AA n=48; regular season n=30, provincials n=32, nationals n=16). The overall bodychecking IR was 17.34/100 team-minutes (95% CI:14.80-20.33), HC 19.09/100 team-minutes (95% CI:16.7421.78), suspected injury 1.53/100 team-minutes (95% CI:1.13-2.09), and suspected concussion 0.74/100 team-minutes (95% CI:0.48-1.13). Only 29% (95% CI:24.97-32.59) of bodychecks and 7% (95% CI:4.76-9.70) of HC1s were penalized. No differences were found in bodychecking, HCs, or suspected injury and concussion IRs between age groups or levels of play. Bodychecking IRs were 64% (IRR=1.64; 95% CI:1.13-2.39) higher in provincials and 24% (IRR=1.24; 95% CI:1.02-1.50) higher in nationals than regular season games. A 31% (IRR=0.69; 95% CI:0.49-0.97) lower rate of HCs was reported in national games compared to provincial games. Bodychecking was the most common mechanism for concussion (70%) and nonconcussion injuries (67%), with concussions most often associated with HC2s (62.5%). Conclusions: Bodychecking and HC1 IRs were high among youth ringette players, despite rules prohibiting them. Future research should target prevention strategies aimed to reduce HC1s and bodychecking to reduce injury and concussion IRs in youth ringette
Phase separation at all interaction strengths in the t-J model
We investigate the phase diagram of the two-dimensional t-J model using a
recently developed Green's Function Monte Carlo method for lattice fermions. We
use the technique to calculate exact ground-state energies of the model on
large lattices. In contrast to many previous studies, we find the model phase
separates for all values of J/t. In particular, it is unstable at the hole
dopings and interaction strengths at which the model was thought to describe
the cuprate superconductors.Comment: Revtex, 4 pages, 3 figures. Some minor changes were made to the text
and figures, and some references were adde
- …