Publications by authors named "R R Chacon"

We study dynamical localization in an ultracold atom confined in an optical lattice that is simultaneously shaken by two competing pulsatile modulations with different amplitudes, periods, and waveforms. The effects of finite-width time pulses, modulation waveforms, and commensurable and incommensurable driving periods are investigated. We describe a particularly complex scenario and conclude that dynamical localization can survive, or even increase, when a periodic modulation is replaced by a quasiperiodic one of equal amplitude.

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Purpose: Breast cancer remains a major public health challenge worldwide, and understanding the trends and changes in breast cancer diagnosis and treatment over time is crucial for improving patient outcomes and guiding public health strategies. The Argentine Society of Mastology has maintained a comprehensive Breast Cancer Registry that provides valuable data for analyzing these trends.

Materials And Methods: This retrospective analysis of the Breast Cancer Registry database evaluated changes in stages at the time of surgery, patterns of surgical care, and factors associated with higher stage diagnoses in patients with breast cancer in Argentina from January 2000 to December 2019.

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An energy-based theory of autoresonance in driven dissipative chains of coupled generic oscillators is discussed on the basis of a variational principle concerning the energy functional. The theory is applied to chains of delayed Duffing-Ueda oscillators and the equations that together govern the autoresonance forces and solutions are derived and solved analytically for generic values of parameters and initial conditions, including the case of quenched time-delay disorder. Remarkably, the presence of retarded potentials with time-delayed feedback drastically modify the autoresonance scenario preventing the growth of the energy oscillation over specific regions of the parameter space.

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Marek's disease is caused by , commonly known as Marek's disease virus (MDV). This pathogen infects various bird species resulting in a range of clinical manifestations. The gene, which is crucial for oncogenesis, has been extensively studied, but molecular investigations of MDV in noncommercial South American birds are limited.

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Chicken Parvovirus (ChPV) belongs to the genus and is implicated in enteric diseases like runting-stunting syndrome (RSS) in poultry. In RSS, chicken health is affected by diarrhea, depression, and increased mortality, causing significant economic losses in the poultry industry. This study aimed to characterize the ChPV genomes detected in chickens with RSS through a metagenomic approach and compare the molecular and evolutionary characteristics within the species.

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