Faculty Opinions recommendation of Desynchronization rate in cell populations: mathematical modeling and experimental data.

The hydrodynamic and thermal state in the contact zone of the layers of a bimetallic product obtained by pouring liquid iron onto a solid steel billet, which changes in time and is responsible for the strength of the diffusion joint and the geometric parameters of the transition layer, has been investigated. Simplified analytical dependences, mathematical modeling data and experimental results of the liquid phase existence time in the contact zone based on research of the melt velocities during pouring and changes in the thermal field are presented. It is shown that simplified calculations data coincide in order and are close in values to the calculations of mathematical modeling and experimental data, which makes it possible to use them for preliminary rough estimates by technologists and metallurgists.

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A Model for Otolith Dynamic Response with a Viscoelastic Gel Layer

Journal of Vestibular Research ◽

10.3233/ves-1991-1205 ◽

1991 ◽

Vol 1 (2) ◽

pp. 139-151

Author(s):

J.W. Grant ◽

J.R. Cotton

Keyword(s):

Mathematical Modeling ◽

Experimental Data ◽

Equations Of Motion ◽

Otolith Organs ◽

Major Contributor ◽

Viscoelastic Solid ◽

Gel Layer ◽

Element System ◽

Experimental Data Analysis ◽

Finite Difference Techniques

The otolith organs were modeled mathematically as a 3-element system consisting of a viscous endolymph fluid in contact with a rigid otoconial layer that is attached to the skull by a gel layer. The gel layer was considered to be a viscoelastic solid, and was modeled as a simple Kelvin material. The governing differential equations of motion were derived and nondimensionalized, yielding 3 nondimensional parameters: nondimensional density, nondimensional viscosity, and nondimensional elasticity. The equations were solved using finite difference techniques on a digital computer. By comparing the model’s response with previous experimental research, values for the nondimensional parameters were found. The results indicate that the inclusion of viscous and elastic effects in the gel layer are necessary for the model to produce otoconial layer deflections that are consistent with physiologic displacements. Future experimental data analysis and mathematical modeling effects should include viscoelastic gel layer effects, as this is a major contributor to system damping and response.

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Mathematical Modeling of Colloidal Ultrafiltration: a Method for Estimation Ultrafiltration Flux Using Experimental Data and Computer Simulations

Membranes and Membrane Processes ◽

10.1007/978-1-4899-2019-5_49 ◽

1986 ◽

pp. 497-505

Author(s):

R. Lundqvist ◽

R. von Schalien

Keyword(s):

Mathematical Modeling ◽

Experimental Data ◽

Computer Simulations

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Inspiring Online Collaborative STEM Learning

MRS Advances ◽

10.1557/adv.2016.362 ◽

2016 ◽

Vol 1 (56) ◽

pp. 3727-3733

Author(s):

Scott A. Sinex ◽

Theodore L. Chambers ◽

Joshua B. Halpern

Keyword(s):

Mathematical Modeling ◽

Experimental Data ◽

General Chemistry ◽

High School Teachers ◽

Informal Education ◽

Student Feedback ◽

Stem Learning ◽

School Teachers ◽

Undergraduate Level ◽

Collaborative Skills

ABSTRACTEducators are advocating a variety of 21st century technologies to increase student engagement and prepare them for the modern workplace. As part of this effort this paper describes the development of several introductory laboratory activities which enhance online collaborative skills in the context of group collaborations. The experiments mostly deal with measurement and error in the context of mathematical modeling. They inculcate online collaborative skills including group writing, collection of experimental data, student feedback, and assessment using forms, spreadsheets with data pooling, real-time graphing/computations, and discussions using chat. These are all available in Google Drive, a free cloudbased application. We have also introduced student collaborative-pair computational spreadsheet assignments, and results of two projects in general chemistry are presented. Building formative assessment into these activities allows for immediate adjustment to instruction. This approach could be used from middle school through the undergraduate level. It can be implemented both in informal education or formal classroom settings by enhancing interactions with remote partners. Student evaluations have been very positive for the variety of activities, as well as from workshop feedback from high school teachers.

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Theoretical Basis for the Measurement of Small Differences in the Length of the Cell Cycle between Two Cell Populations

The Open Biology Journal ◽

10.2174/1874196700902010095 ◽

2009 ◽

Vol 2 (1) ◽

pp. 95-100

Author(s):

Juan Sebastian Yakisich

Keyword(s):

Experimental Data ◽

Cell Cycle ◽

Theoretical Basis ◽

Cycle Length ◽

Cell Populations ◽

Experimental Variability ◽

Cell Strains ◽

Novel Strategy ◽

Cell Cycle Length

The length of the cell cycle (TC) is a tight regulated process and is important for proper development and homeostasis. Although several methods are available for estimating the duration of the cell cycle, it is difficult to determinate small differences of TC between two different cell populations due to biological and/or experimental variability. A novel strategy based in co-cultivation of two cell strains followed by a series of dilution and propagation of the culture will allow the quantification of very small differences in the length of two cell populations at resolution levels not possible at present with current methods. This is achieved by a separation of the endpoint variable measured to compare between two cell populations. The theoretical basis of this approach is discussed in the context of published experimental data and simulation of idealized experiments using virtual strains of different cell cycle length.

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Data Mining and Optimize TCM Prescription Compatibility Based on WDS-PLS

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.687-691.1385 ◽

2014 ◽

Vol 687-691 ◽

pp. 1385-1388

Author(s):

Zhuo Wang ◽

Bin Nie ◽

Ri Yue Yu

Keyword(s):

Mathematical Modeling ◽

Experimental Data ◽

Data Mining ◽

Regression Coefficient ◽

Uniform Design ◽

Herbal Medicines ◽

Data Standardization ◽

Modeling Data ◽

Pls Method ◽

Original Formula

Data mining and optimize traditional Chinese medicine (TCM) prescription compatibility based on wavelet denoise spectral and partial least squares (WDS-PLS). Method: First of all, experimental design: with reference to the original formula, the herbal medicines in a prescription designed nine formula based on mixing uniform design; Secondly, obtain experimental data and data standardization; Finally, mathematical modeling, data mining and optimize TCM prescription compatibility base on WDS-PLS.Results: gain the regression coefficient and equation, VIP sorting, loadings Bi plot, and seek out the optimized direction of the prescription. Conclusion: the method data mining and optimize the compatibility of the dachengqi decoction is feasible and effective.

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MATHEMATICAL MODELING OF IMMUNE-INFLAMMATORY REACTION IN ACUTE PNEUMONIA

Journal of Biological System ◽

10.1142/s021833909500040x ◽

1995 ◽

Vol 03 (02) ◽

pp. 429-439 ◽

Cited By ~ 7

Author(s):

S. G. RUDNEV ◽

A. A. ROMANYUKHA

Keyword(s):

Mathematical Modeling ◽

Experimental Data ◽

Mathematical Model ◽

Immune Response ◽

Sensitivity Analysis ◽

Inflammatory Reaction ◽

Humoral Immune ◽

Disease Characteristics ◽

Acute Pneumonia ◽

Lung Resistance

Using ordinary differential equations, we propose a mathematical model describing an “averaged” dynamics of variables involved in which some parameters are shown to be important characteristics of lung resistance. The model consists of modified D.A. Lauffenburger’s mathematical model for inflammatory reaction in lungs, and the model of humoral immune response (G. I. Marchuk). Coefficients are identified against clinical and experimental data. We attempt to elucidate some disease characteristics in terms of sensitivity analysis of model solutions with respect to parameters variations.

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Evidence for heterogeneous subsarcolemmal Na+ levels in rat ventricular myocytes

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00637.2018 ◽

2019 ◽

Vol 316 (5) ◽

pp. H941-H957 ◽

Cited By ~ 4

Author(s):

J. Skogestad ◽

G. T. Lines ◽

W. E. Louch ◽

O. M. Sejersted ◽

I. Sjaastad ◽

...

Keyword(s):

Mathematical Modeling ◽

Experimental Data ◽

Cardiac Myocytes ◽

Ventricular Myocytes ◽

Homogeneous Model ◽

Cardiac Contractility ◽

Channel Activation ◽

Internal Solution ◽

Rat Ventricular Myocytes ◽

Quiescent Cells

The intracellular Na+ concentration ([Na+]) regulates cardiac contractility. Previous studies have suggested that subsarcolemmal [Na+] is higher than cytosolic [Na+] in cardiac myocytes, but this concept remains controversial. Here, we used electrophysiological experiments and mathematical modeling to test whether there are subsarcolemmal pools with different [Na+] and dynamics compared with the bulk cytosol in rat ventricular myocytes. A Na+ dependency curve for Na+-K+-ATPase (NKA) current was recorded with symmetrical Na+ solutions, i.e., the same [Na+] in the superfusate and internal solution. This curve was used to estimate [Na+] sensed by NKA in other experiments. Three experimental observations suggested that [Na+] is higher near NKA than in the bulk cytosol: 1) when extracellular [Na+] was high, [Na+] sensed by NKA was ~6 mM higher than the internal solution in quiescent cells; 2) long trains of Na+ channel activation almost doubled this gradient; compared with an even intracellular distribution of Na+, the increase of [Na+] sensed by NKA was 10 times higher than expected, suggesting a local Na+ domain; and 3) accumulation of Na+ near NKA after trains of Na+ channel activation dissipated very slowly. Finally, mathematical models assuming heterogeneity of [Na+] between NKA and the Na+ channel better reproduced experimental data than the homogeneous model. In conclusion, our data suggest that NKA-sensed [Na+] is higher than [Na+] in the bulk cytosol and that there are differential Na+ pools in the subsarcolemmal space, which could be important for cardiac contractility and arrhythmogenesis. NEW & NOTEWORTHY Our data suggest that the Na+-K+-ATPase-sensed Na+ concentration is higher than the Na+ concentration in the bulk cytosol and that there are differential Na+ pools in the subsarcolemmal space, which could be important for cardiac contractility and arrhythmogenesis. Listen to this article’s corresponding podcast at https://ajpheart.podbean.com/e/heterogeneous-sodium-in-ventricular-myocytes/ .

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