arXiv subjects

Pablo Abuin

Publications and source records attributed to Pablo Abuin.

4 recordsLinked to original sources

arXiv2021

Optimal control strategies to tailor antivirals for acute infectious diseases in the host

Several mathematical models in SARS-CoV-2 have shown how target-cell model can help to understand the spread of the virus in the host and how potential candidates of antiviral treatments can help to control the virus. Concepts as equilibrium and stability show to be crucial to qualitatively determine the best alternatives to schedule drugs, according to effectivity in inhibiting the virus infection and replication rates. Important biological events such as rebounds of the infections (when antivirals are incorrectly interrupted) can also be explained by means of a dynamic study of the target-cell model. In this work, a full characterization of the dynamical behavior of the target-cell models under control actions is made and, based on this characterization, the optimal fixed-dose antiviral schedule that produces the smallest amount of dead cells (without viral load rebounds) is computed. Several simulation results - performed by considering real patient data - show the potential benefits of both, the model characterization and the control strategy.

math.OC↗

arXiv2020

Dynamical Characterization of Antiviral Effects in COVID-19

Mathematical models describing SARS-CoV-2 dynamics and the corresponding immune responses in patients with COVID-19 can be critical to evaluate possible clinical outcomes of antiviral treatments. In this work, based on the concept of virus spreadability in the host, antiviral effectiveness thresholds are determined to establish whether or not a treatment will be able to clear the infection. In addition, the virus dynamic in the host -- including the time-to-peak and the final monotonically decreasing behavior -- is chracterized as a function of the treatment initial time. Simulation results, based on nine real patient data, show the potential clinical benefits of a treatment classification according to patient critical parameters. This study is aimed at paving the way for the different antivirals being developed to tackle SARS-CoV-2.

math.DS↗

arXiv2020

Characterization of SARS-CoV-2 Dynamics in the Host

While many epidemiological models have being proposed to understand and handle COVID-19, too little has been invested to understand how the virus replicates in the human body and potential antiviral can be used to control the replication cycle. In this work, using a control theoretical approach, validated mathematical models of SARS-CoV-2 in humans are properly characterized. A complete analysis of the main dynamic characteristic is developed based on the reproduction number. The equilibrium regions of the system are fully characterized, and the stability of such a regions, formally established. Mathematical analysis highlights critical conditions to decrease monotonically SARS-CoV-2 in the host, such conditions are relevant to tailor future antiviral treatments. Simulation results show the potential benefits of the aforementioned system characterization.

math.DS↗

arXiv2014

On planetary torque signals and sub-decadal frequencies in the discharges of large rivers

We explore the arguments presented in the past linking changes in the angular momentum $modulus$, $|{\bf L}|$, of the Sun's barycentric orbit, with the discharges of Po River in Europe and Paran\'a River in South America, looking for any evidence regarding to a possible underlying physical mechanism. We clarify the planetary effect on solar torque presenting new analyses and results; we also improve prior results on Paran\'a River's cycles finding significant spectral lines around 6.5 yr, 7.6 yr, 8.7 yr, and 10.4 yr. We show that the truly important dynamical parameter in this issue is the {\it vectorial} planetary torque. Moreover, following the variations of ${\bf L}$ respect to the Sun's spin axis of rotation (i.e., a LS relationship), we found virtually the same Paran\'a River discharge peaks: 6.3 yr, 7.7 yr, 8.6 yr and 9.9 yr. An analisys based on Magnitude Squared Coherence and Wavelet Coherence between Paran\'a River discharge and our LS relationship shows significant, although intermittently, coherence near 8-yr periodicities. Wavelet Coherence also shows big and significant regions of coherence inside 12-19 yr band. Our results ruled out classical tidal effects in this problem; but suggest that, if these rivers are trully related to solar barycentric motion, the physical origin of this connection might be related to a working solar spin-orbit interaction.

astro-ph.EP↗