Blood-brain barrier disruption by low-frequency ultrasound.
Background and Purpose— A recent study showed a dramatic increase in cerebral hemorrhage comprising atypical locations with low-frequency ultrasound–mediated recombinant tissue plasminogen activator–thrombolysis in humans. Here, we provide a possible explanation for this phenomenon by a side effect observed in a study using the similar ultrasound device. Methods— The study was originally undertaken to investigate by transcranial Doppler sonography, positron emission tomography and perfusion MRI whether transcranial application of wide-field low-frequency ultrasound (300 kHz) improves cerebral hemodynamics in patients with cerebral small vessel disease. Results— Showing no clear positive ef…
Minimally doubled fermions at one loop
Minimally doubled fermions have been proposed as a cost-effective realization of chiral symmetry at non-zero lattice spacing. Using lattice perturbation theory at one loop, we study their renormalization properties. Specifically, we investigate the consequences of the breaking of hyper-cubic symmetry, which is a typical feature of this class of fermionic discretizations. Our results for the quark self-energy indicate that the four-momentum undergoes a renormalization which contains a linearly divergent piece. We also compute renormalization factors for quark bilinears, construct the conserved vector and axial-vector currents and verify that at one loop the renormalization factors of the lat…
„Dopingtalk“ im Internet – Lernmilieus zum Substanzgebrauch im Sport
Soziale Medien tragen in vielerlei Hinsicht dazu bei, dass sich Akteure Identitat verschaffen, vernetzen konnen, kommunizieren und voneinander lernen. Dies gilt im Besonderen auch fur jene Sozialbereiche, in denen abweichendes Verhalten zirkuliert und normalisiert wird. Der Substanzgebrauch im Freizeitsport ist ein solches, vermeintlich anormales soziales Phanomen, das sich nicht nur im kommerziellen Fitnessstudio beobachten lasst. Dopingaffine Internetforen sind das tragende Tableau, uber das der Substanzkonsum im Sport angeboten, weitergetragen, erlernt und auf Dauer gestellt wird. Mit diesem soziologischen Beitrag wird ein Einblick in den „Dopingtalk“ von konsumierenden Anfangern bis zu …