Self-similarity of single-channel transmission for electron transport in nanowires

We demonstrate that the single-channel transmission in the resonance tunneling regime exhibits self-similarity as a function of the nanowire length and the energy of incident electrons. The self-similarity is used to design the nonlinear transformation of the nanowire length and energy which, on the basis of known values of transmission for a certain region on the energy-length plane, yields transmissions for other regions on this plane. Test calculations with a one-dimensional tight-binding model illustrate the described transformations. Density function theory based transport calculations of Na atomic wires confirm the existence of the self-similarity in the transmission

Aspectos de la respuesta inmune innata en las infecciones intramamarias causadas por Staphylococcus aureus en bovinos

ResumenStaphylococcus aureus es el principal agente causante de mastitis bovina en Argentina y en el mundo. Esta bacteria ocasiona infecciones crónicas que generan importantes pérdidas a los productores y la industria lechera. El objetivo de este artículo es caracterizar los mecanismos que intervienen en la infección causada por S. aureus en la glándula mamaria bovina, evaluando dos aspectos diferentes del proceso infeccioso: por un lado, lo vinculado con la respuesta inmune innata por parte del hospedador, y por otro, la capacidad de la bacteria para evadir el sistema inmune e interactuar con diferentes tipos celulares. La exploración de la interacción de S. aureus con el sistema inmune de la glándula mamaria bovina permitirá identificar blancos para delinear nuevas alternativas preventivas o curativas, que contribuyan a evitar o eliminar las infecciones causadas por este organismo.AbstractStaphylococcus aureus is the pathogen most frequently isolated from bovine mastitis worldwide, causing chronic intramammary infections that limit profitable dairying. The objective of this article is to characterize the mechanisms involved in S. aureus mammary gland infections considering two different aspects of the infectious process; on the one hand, the aspects involved in the host innate immune response and on the other hand, the capacity of this organism to evade the immune system and interact with different cell types. The exploration of S. aureus interactions with the immune response of bovine mammary gland will help identify targets to outline new preventive or curative alternatives for intramammary infections caused by this organism

Management and Productivity of Key Integrated Crop-Livestock Systems in Uruguay: The Palo a Pique Long-Term Experiment’s Third Phase

Integrated Crop Livestock Systems (ICLSs) use productive diversification as a strategy to improve productivity and land use efficiency. Pasture Crop Rotations are a part of ICLSs and imply a pasture phase included in the sequence of crops. The main reasons to include pastures in crop systems are low productivity of natural grasslands and increased crop yield after a pasture phase. Our objective was to analyze the productivity indicators and management of four ICLSs that combine crop and livestock production, with data collected over a 3 y period (2019–2022). The experimental site was The Palo a Pique (Treinta y Tres, Uruguay) long-term experiment installed in 1995, located in the subtropical climate zone and on Oxyaquic Argiudolls soils (3% average slope). Systems evaluated were CC (continuous cropping), SR (two years idem CC, two years of pastures), LR (two years idem CC, four years of pastures) and FR (continuous pasture with Tall Fescue). Liveweight (LW) production, grain production and dry matter (DM) production were evaluated. Liveweight production was higher in CC and SR (426 and 418 kg LW/ha) than in LR (369 kg LW/ha) and FR (310 kg LW/ha). DM production was higher in FR and SR (6867 and 5763 kg DM/ha/year) than in LR (5399 kg DM/ha/year) and CC (5206 kg DM/ha/year). Grain production was 10%, 16% and 9% lower in soybean, wheat and sorghum in CC

Detailed Interstellar Polarimetric Properties of the Pipe Nebula at Core Scales

We use R-band CCD linear polarimetry collected for about 12000 background field stars in 46 fields of view toward the Pipe nebula to investigate the properties of the polarization across this dark cloud. Based on archival 2MASS data we estimate that the surveyed areas present total visual extinctions in the range 0.6 < Av < 4.6. While the observed polarizations show a well ordered large scale pattern, with polarization vectors almost perpendicularly aligned to the cloud's long axis, at core scales one see details that are characteristics of each core. Although many observed stars present degree of polarization which are unusual for the common interstellar medium, our analysis suggests that the dust grains constituting the diffuse parts of the Pipe nebula seem to have the same properties as the normal Galactic interstellar medium. Estimates of the second-order structure function of the polarization angles suggest that most of the Pipe nebula is magnetically dominated and that turbulence is sub-Alvenic. The Pipe nebula is certainly an interesting region where to investigate the processes prevailing during the initial phases of low mass stellar formation.Comment: 20 pages, 23 figures, Accepted for The Astrophysical Journa

HLA-Associated viral mutations are common in human immunodeficiency virus type 1 elite controllers

Elite controllers (EC) of human immunodeficiency virus type 1 (HTV-1) maintain viremia below the limit of detection without antiretroviral treatment. Virus-specific cytotoxic CD8+ T lymphocytes are believed to play a crucial role in viral containment, but the degree of immune imprinting and compensatory mutations in EC is unclear. We obtained plasma gag, pol, and nef sequences from HLA-diverse subjects and found that 30 to 40% of the predefined HLA-associated polymorphic sites show evidence of immune selection pressure in EC., compared to approximately 50% of the sites in chronic progressors. These data indicate ongoing viral replication and escape from cytotoxic T lymphocytes are present even in strictly controlled HTV-1 infection