We show that it is possible for fermion condensation of the Nambu-Jona-Lasinio type to induce a nonsingular bounce that smoothly connects a phase of slow contraction to a phase of expansion. A chiral condensate-a nonzero vacuum expectation value of the spinor bilinear ⟨Ψ[over ¯]Ψ⟩-can form spontaneously after a slow contraction phase smooths and flattens the universe and the Ricci curvature exceeds a critical value. In this approach, a high density of spin-aligned free fermions is not required, which avoids the problem of generating a large anisotropy and initiating chaotic mixmaster behavior during the bounce phase.
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http://dx.doi.org/10.1103/PhysRevLett.131.091001 | DOI Listing |
Front Physiol
January 2025
Liberal Arts Department, American University of the Middle East, Egaila, Kuwait.
Introduction: The aim of the present study was to investigate the effects of eccentric phase tempo in squats on hypertrophy, strength, and contractile properties of the quadriceps femoris (QF) muscle.
Methods: Eighteen participants (10 males and 8 females, age 24.0 ± 1.
Hernia
January 2025
The Swedish Institute for Health Economics, Svartmangatan 18, Stockholm, 111 29, Sweden.
Purpose: Small-bites suturing technique for laparotomy closure is now recommended as the standard of care. However, uptake of the practice remains slow. A medical technology called the SutureTOOL has been developed which can facilitate implementation of small-bites.
View Article and Find Full Text PDFVision (Basel)
January 2025
Centre Gilles Gaston Granger, UMR 7304 Centre National de la Recherche Scientifique, Aix Marseille Université, 13621 Aix-en-Provence, France.
The appearance of an object triggers an orienting gaze movement toward its location. The movement consists of a rapid rotation of the eyes, the saccade, which is accompanied by a head rotation if the target eccentricity exceeds the oculomotor range and by a slow eye movement if the target moves. Completing a previous report, we explain the numerous points that lead to questioning the validity of a one-to-one correspondence relation between measured physical values of gaze or head orientation and neuronal activity.
View Article and Find Full Text PDFJ Physiol Sci
January 2025
Department of Frontier Health Sciences, Graduate School of Human Health Sciences, Tokyo Metropolitan University, 7-2-10 Higashiogu, Arakawa-Ku, 116-8551, Tokyo, Japan. Electronic address:
Actin linked regulatory mechanisms are known to contribute contraction/relaxation in smooth muscle. In order to clarify whether modulation of polymerization/depolymerization of actin filaments affects relaxation process, we examined the effects of cytochalasin D on relaxation process by Ca removal after Ca-induced contraction of β-escin skinned (cell membrane permeabilized) taenia cecum and carotid artery preparations from guinea pigs. Cytochalasin D, an inhibitor of actin polymerization, significantly suppressed the force during relaxation both in skinned taenia cecum and carotid artery.
View Article and Find Full Text PDFInt J Gen Med
January 2025
Department of Cardiology, The First People's Hospital of Yibin, Yibin, Sichuan, People's Republic of China.
Objective: To investigate the correlation between premature ventricular contraction (PVC) frequency and heart rate (HR) in Chinese adults, with an emphasis on sex-specific differences in clinical characteristics.
Patients And Methods: This retrospective study analyzed 24-hour Holter monitoring data from 478 inpatients at the First People's Hospital of Yibin between January 2021 and December 2022. The inclusion criteria were age ≥18 years, ≥20 hours of Holter recording, frequent PVCs (≥ 500 PVCs), and complete clinical profiles.
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