Anomalous entropy-driven kinetics of dislocation nucleation.

The kinetics of dislocation reactions, such as dislocation multiplication, controls the plastic deformation in crystals beyond their elastic limit, therefore critical mechanisms in a number of applications in materials science. We present a series of large-scale molecular dynamics simulations that shows that one such type of reactions, the nucleation of dislocation at free surfaces, exhibit unconventional kinetics, including unexpectedly large nucleation rates under compression, very strong entropic stabilization under tension, as well as strong non-Arrhenius behavior. These unusual kinetics are quantitatively rationalized using a variational transition state theory approach coupled with an efficient numerical scheme for the estimation of vibrational entropy changes.

Dispersal of influenza virus populations within the respiratory tract shapes their evolutionary potential.

Viral infections are characterized by dispersal from an initial site to secondary locations within the host. How the resultant spatial heterogeneity shapes within-host genetic diversity and viral evolutionary pathways is poorly understood. Here, we show that virus dispersal within and between the nasal cavity and trachea maintains diversity and is therefore conducive to adaptive evolution, whereas dispersal to the lungs gives rise to population heterogeneity.

A survey of lip lesions diagnosed in a single institution: A clinicopathological study.

Background: The aim of this study was to assess the clinicopathological features of lip lesions diagnosed in a single Oral Pathology service in Brazil.

Material And Methods: It was a cross-sectional study based on secondary data. Between 2000 and 2019, all lip lesions diagnosed in an Oral Pathology service in Brazil were analyzed.

Cyclodehydrogenation of molecular nanographene precursors catalyzed by atomic hydrogen.

Atomically precise synthesis of graphene nanostructures on semiconductors and insulators has been a formidable challenge. In particular, the metallic substrates needed to catalyze cyclodehydrogenative planarization reactions limit subsequent applications that exploit the electronic and/or magnetic structure of graphene derivatives. Here, we introduce a protocol in which an on-surface reaction is initiated and carried out regardless of the substrate type.

Genomic Evolution of the SARS-CoV-2 Omicron Variant in Córdoba, Argentina (2021-2022): Analysis of Uncommon and Prevalent Spike Mutations.

Understanding the evolutionary patterns and geographic spread of SARS-CoV-2 variants, particularly Omicron, is essential for effective public health responses. This study focused on the genomic analysis of the Omicron variant in Cordoba, Argentina from 2021 to 2022. Phylogenetic analysis revealed the dominant presence of BA.