We study the effect of an asymmetry on the transport properties of an active Brownian particle. We demonstrate the existence of a critical force or, more generally, of a critical asymmetry that separates parameter regimes of giant diffusion from those with reliable directed transport. We derive a condition for the critical asymmetry by means of an exact expression for the diffusion coefficient and by a simplified discrete picture. A critical asymmetry, as predicted by the simple model, is also found in a detailed model of coupled molecular motors displaying bidirectional motion.
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http://dx.doi.org/10.1103/PhysRevLett.101.190603 | DOI Listing |
J Clin Med
January 2025
Neuromuscular Control Laboratory, Yeungnam University, Gyeongsan-si 38541, Republic of Korea.
: Gait disturbances characterized by asymmetries in lower limb strength and gait patterns are frequently observed in stroke patients, which increases gait variability and fall risk. However, the extent to which lower limb strength asymmetry influences gait asymmetry and variability in this population remains unclear. : This cross-sectional study included 84 participants, comprising stroke survivors and age- and sex-matched healthy older adults.
View Article and Find Full Text PDFRev Med Chil
November 2024
Escuela de Ingeniería Biomédica, Universidad de Valparaíso, Valparaíso, Chile.
Before 1990, Chile showed fewer medical schools, six in total, increasing to 13 by 2000. From then on, there was an explosive increase, reaching 29 faculties or schools by 2024. Medical students increased from 1,816 in 2010 to 3,000 by 2024.
View Article and Find Full Text PDFEntropy (Basel)
January 2025
Department of Condensed Matter Physics, University of Barcelona, Martí i Franquès 1, E-08028 Barcelona, Spain.
Directed networks are essential for representing complex systems, capturing the asymmetry of interactions in fields such as neuroscience, transportation, and social networks. Directionality reveals how influence, information, or resources flow within a network, fundamentally shaping the behavior of dynamical processes and distinguishing directed networks from their undirected counterparts. Robust null models are crucial for identifying meaningful patterns in these representations, yet designing models that preserve key features remains a significant challenge.
View Article and Find Full Text PDFDent J (Basel)
December 2024
Department of Oral Medicine & Pathology and Hospital Dentistry, School of Dentistry, National and Kapodistrian University of Athens (NKUA), Greece 2 Thivon Street, 11527 Athens, Greece.
Burkitt lymphoma (BL) is an aggressive non-Hodgkin lymphoma (NHL), subdivided into endemic, sporadic, and immunodeficiency-associated forms. While jaw lesions are common in endemic BL, they are infrequent in sporadic cases, only rarely constituting the first manifestation of the disease. The aim of this study is to present a rare pediatric case of sporadic BL first manifesting as gingival swellings and tooth hypermobility and provide a review of all the published sporadic BL case reports as the first sign of disease.
View Article and Find Full Text PDFNat Struct Mol Biol
January 2025
Department of Integrative Structural and Computational Biology, Scripps Research, La Jolla, CA, USA.
Transthyretin (TTR) is a natively tetrameric thyroxine transporter in blood and cerebrospinal fluid whose misfolding and aggregation causes TTR amyloidosis. A rational drug design campaign identified the small molecule tafamidis (Vyndamax) as a stabilizer of the native TTR fold, and this aggregation inhibitor is regulatory agency approved for the treatment of TTR amyloidosis. Here we used cryo-EM to investigate the conformational landscape of this 55 kDa tetramer in the absence and presence of one or two ligands, revealing inherent asymmetries in the tetrameric architecture and previously unobserved conformational states.
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