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A theoretical model of the evolution of actuarial senescence under environmental stress

H. Watson, A.A. Cohen, C. Isaksson
2015 Experimental Gerontology  
We used a theoretical evolutionary framework to quantify the potential consequences for the evolution of actuarial senescence in response to exposure to simultaneous physiological stressors one versus  ...  In a model in which multiple stressors have additive effects on physiology, species may retain greater capacity to recover, or respond adaptively, to environmental challenges.  ...  Acknowledgements We thank Marco Klein Heerinbrink for helpful discussion concerning mathematical models.  ... 
doi:10.1016/j.exger.2015.08.009 pmid:26335620 pmcid:PMC4710637 fatcat:h5iiwjulqra7nd46xz5dxip72u

Correction of global physiology in resting-state functional near-infrared spectroscopy

Pradyumna Lanka, Heather Bortfeld, Theodore J. Huppert
2022 Neurophotonics  
Results: Consistent with previous work on bivariate correlation models, our results demonstrate that robust statistics and pre-whitening are effective methods to correct for motion artifacts and autocorrelation  ...  Approach: Using numerically simulated RS-fNIRS data, we compared the rates of true and false positives for several connectivity analysis pipelines.  ...  Heather Bortfeld, and a grant from the NIH (Grant No. R01EB028248) to Dr. Theodore Huppert.  ... 
doi:10.1117/1.nph.9.3.035003 pmid:35990173 pmcid:PMC9386281 fatcat:trba3soebbg7plbnj5lvujqqpe

Towards a Generic Tool for Prediction of Meropenem Systemic and Infection-Site Exposure: A Physiologically Based Pharmacokinetic Model for Adult Patients with Pneumonia

Pauline Thémans, Pierre Marquet, Joseph J. Winkin, Flora T. Musuamba
2019 Drugs in RD  
Objective The objective of this study was to develop a physiologically based pharmacokinetic model for meropenem using a retrograde approach, which could serve as a basis for prediction of the systemic  ...  Conclusions We successfully developed a physiologically based pharmacokinetic model for meropenem in adult patients to be used as a basis for prediction of concentrations in different groups of patients  ...  The further advantage of a generic PBPK model is to propose a robust tool for the development of dosing algorithms.  ... 
doi:10.1007/s40268-019-0268-x fatcat:g6pdtargebdb3nin5egx4juzku

Model-based interpretation of cardiac beats by evolutionary algorithms: signal and model interaction

Alfredo I Hernández, Guy Carrault, Fernando Mora, Alain Bardou
2002 Artificial Intelligence in Medicine  
13 This paper presents a new approach for cardiac beat interpretation, based on a direct integration 14 between a model and observed ECG signals.  ...  Physiological knowledge is represented by means of a 15 semi-quantitative model of the cardiac electrical activity.  ...  All the information obtained from the 22 model for each individual l (i.e. time of occurrence of simulated P-waves, simulated action potentials 23for all structures and the ladder diagram) is saved for  ... 
doi:10.1016/s0933-3657(02)00078-7 pmid:12446079 fatcat:l457tksrkzgh7lgup6nrxcenli

The nature of robustness in development

H.F. Nijhout
2002 Bioessays  
A trait is robust to a genetic or environmental variable if its variation is weakly correlated with variation in that variable.  ...  Here we explore how developmental mechanisms determine and alter the correlation structure between genes and the traits they control.  ...  Acknowledgments I am indebted to Mark Rausher for insightful discussions and constructive critiques of early versions of this work.  ... 
doi:10.1002/bies.10093 pmid:12111738 fatcat:bpsbwv63lzckfativqfkn62owi

Regulation of valve interstitial cell homeostasis by mechanical deformation: implications for heart valve disease and surgical repair

Salma Ayoub, Chung-Hao Lee, Kathryn H. Driesbaugh, Wanda Anselmo, Connor T. Hughes, Giovanni Ferrari, Robert C. Gorman, Joseph H. Gorman, Michael S. Sacks
2017 Journal of the Royal Society Interface  
We are developing constitutive models for the exogenously crosslinked tissue and the PS process using a mixture approach based on the reference state evolution of the material subcomponents.  ...  PS is a result of the scission healing of the glutaraldehyde crosslinker, which allows for recrosslinking of the extracellular matrix in the BHV leaflets.  ...  Repair strategies are simulated using the patientspecific and population-averaged models.  ... 
doi:10.1098/rsif.2017.0580 pmid:29046338 fatcat:4pg3mtl5lvhcdfrji5zeomgchq

Faithful Models of Viral Fitness can be Inferred from Mutation Patterns in Viral DNA Sequences Sampled from a Population

Karthik Shekhar, Mehran Kardar, Arup K. Chakraborty
2013 Biophysical Journal  
Genetic robustness is a static property that is unnecessary for homeostasis. It is, however, essential for evolution to occur and seems to coexist with homeostasis in many biological processes.  ...  Here, we find a strong statistical correlation between adaptive homeostasis and genetic robustness in N-node enzymatic networks, providing a foundation for the unitary character of evolutionary fitness  ...  This integration of a metabolic model, which is a bottom up reconstruction from the genome, with single cell proteomics data gives us new insight into the effect of noise on the physiology of cell populations  ... 
doi:10.1016/j.bpj.2012.11.2732 fatcat:33z4mwilyrhzvkbojwdvi2tdxi

Cortical Transformation of Spatial Processing for Solving the Cocktail Party Problem: A Computational Model

J. Dong, H. S. Colburn, K. Sen
2016 eNeuro  
We present the model network along with testable experimental paradigms as a starting point for understanding the transformation and organization of spatial information from midbrain to cortex.  ...  monitoring of a broader acoustic space when there is no competition.  ...  Lateral inhibition in the model can account for the spatial tuning and spatial segregation properties of recorded units. a-c, Left, Model structure. Center, Simulated spatial grid.  ... 
doi:10.1523/eneuro.0086-15.2015 pmid:26866056 pmcid:PMC4745179 fatcat:z3ekexknejdqjaiujuecvd6c2e

Breiman's two cultures: You don't have to choose sides [article]

Andrew C. Miller, Nicholas J. Foti, Emily B. Fox
2021 arXiv   pre-print
This dichotomy overlooks a third set of models - mechanistic models derived from scientific theories (e.g., ODE/SDE simulators).  ...  Breiman's classic paper casts data analysis as a choice between two cultures: data modelers and algorithmic modelers.  ...  For example, health applications present a number of issues that frustrate the formation of robust predictions and inferences.  ... 
arXiv:2104.12219v1 fatcat:ne5f73yrqfftxlwv7vgb6ybhte

Breiman's Two Cultures: You Don't Have to Choose Sides

Andrew C. Miller, Nicholas J. Foti, Emily B. Fox
2021 Observational Studies  
This dichotomy overlooks a third set of models -mechanistic models derived from scientific theories (e.g., ODE/SDE simulators).  ...  Breiman's classic paper casts data analysis as a choice between two cultures: data modelers and algorithmic modelers.  ...  For example, health applications present a number of issues that frustrate the formation of robust predictions and inferences.  ... 
doi:10.1353/obs.2021.0003 fatcat:omebjty3i5afrlmpve7fmo6zti

Estimating Interval Process Models for Type 1 Diabetes for Robust Control Design

Harald Kirchsteiger, Giovanna Castillo Estrada, Stephan Pölzer, Eric Renard, Luigi del Re
2011 IFAC Proceedings Volumes  
The model together with the parameter intervals can be used for robust control design.  ...  The model is able to simulate the glucose concentration in blood and uses the information of carbohydrate content of the breakfast and the administered insulin injections as inputs.  ...  As a first step towards such a model, we concentrate to model the breakfast data of a given population.  ... 
doi:10.3182/20110828-6-it-1002.03770 fatcat:3obmlrorofazdigpl23ftymvau

Heterogenity in Protein Copy Numbers induces Metabolic Variability in Modeled E. coli Populations

Piyush Labhsetwar, John Cole, Elijah Roberts, Nathan Price, Zaida Luthey-Schulten
2013 Biophysical Journal  
This integration of a metabolic model, which is a bottom up reconstruction from the genome, with single cell proteomics data gives us new insight into the effect of noise on the physiology of cell populations  ...  We performed simulations of a discrete molecular quasispecies model that reveals the essential role of immune pressure in driving viral evolution on its intrinsic fitness landscape.  ... 
doi:10.1016/j.bpj.2012.11.2731 fatcat:yln5gg4okbg4rn2tg7pgnnssdi

A positive feedback at the cellular level promotes robustness and modulation at the circuit level

Julie Dethier, Guillaume Drion, Alessio Franci, Rodolphe Sepulchre
2015 Journal of Neurophysiology  
We show that this slow positive feedback is required to endow the network rhythm with physiological modulation and robustness properties.  ...  Dethier J, Drion G, Franci A, Sepulchre R. A positive feedback at the cellular level promotes robustness and modulation at the circuit level.  ...  Dethier is supported by the Fonds de la Recherche Scientifique-FNRS (Belgian Fund for Scientific Research). G.  ... 
doi:10.1152/jn.00471.2015 pmid:26311181 pmcid:PMC4620135 fatcat:pzoyjdddjff47b6vkxfolgitza

Comprehensive Uncertainty Quantification and Sensitivity Analysis for Cardiac Action Potential Models

Pras Pathmanathan, Jonathan M. Cordeiro, Richard A. Gray
2019 Frontiers in Physiology  
); (iii) used a single "hyper-parameter" to study increasing levels of parameter uncertainty; (iv) performed UQ and SA for a range of model-derived quantities with physiological relevance; and (v) present  ...  This approach allowed us to demonstrate that, for this model, the simulated AP is fully robust to low levels of parameter uncertainty - to our knowledge the first time this has been shown of any cardiac  ...  the need for a model output are not robust to the input uncertainty.  ... 
doi:10.3389/fphys.2019.00721 pmid:31297060 pmcid:PMC6607060 fatcat:fmfwe2gsifej7fpaw3s5gypbku

A positive feedback at the cellular level promotes robustness and modulation at the circuit level [article]

Julie Dethier, Guillaume Drion, Alessio Franci, Rodolphe Sepulchre
2014 arXiv   pre-print
This study thereby identifies an essential cellular property to be retained at the network level in modeling network robustness and modulation.  ...  We show that this slow- positive feedback is necessary and sufficient to endow the network rhythm with physiological modulation and robustness properties.  ...  We simulated a sixteen-neuron network with two populations, with a different noise source for each neuron ( Figure 5 ). The results are consistent with the robustness against parameter variability.  ... 
arXiv:1409.6338v2 fatcat:p2dn6gzmj5gyhb6va6rhh3nrmy
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