Blog updated.

Showing posts with label exams. Show all posts
Showing posts with label exams. Show all posts

Wednesday, December 3, 2014

Stochastic models in medicine and life science (requirement for 2nd year, talk)


Whether we investigate the growth and interactions of an entire population, the evolution of DNA sequences, the inheritance of traits, or the spread of disease, biological systems are marked by change and adaptation [1]. It is often said that biology is going to be the science of the 21st  century as physics was the science of the 20th [3,4]. Computers, and computer science ideas and techniques, are of course an important part of all these scientific and engineering activities [4].
Indeed this represents the challenges in biological modeling compared to traditional branches such as physics. In general the adaptations and changes are much faster than physical systems, what makes the modeling and analysis in most of the cases a formidable task.

When I first read a biology textbook, it was like reading a thriller. Every page brought a new shock. As a physicist, I was used to studying matter that obeys precise mathematical laws. But cells are matter that dances. Structures spontaneously assemble, perform elaborate biochemical functions, and vanish effortlessly when their work is done. Molecules encode and process information virtually without errors, despite the fact that they are under strong thermal noise and embedded in a dense molecular soup. The main message is that biological systems contain an inherent simplicity  [3] .

In the pharmaceutical industry, the incorporation of the disciplines of pharmacokinetics, pharmacodynamics, and drug metabolism (PK/PD/DM) into various drug development processes has been recognized to be extremely important for appropriate compound selection and optimization [2].

Conerstones of my research

1. Introduction
The first year was dedicated to: 1) achieving the minimal requirements in terms of credits; 2) gathering the maximum amount of knowledge. The academic activities was divided into mathematical and biomedical; and master-level disciplines, summer schools, readings, and short courses. The activities was either suggested by the advisors, prof. Palumbo and prof. Manes, or chosen by me. Some of the disciplines was followed on the hope to increase my theoretical background.
2. Master-level disciplines
  • Controllo Ottimo. Prof E De Santis (UAQ): in theory important for optimum regimen design in medical treatments. As result, a talk in the IASI-CNR in June and a paper in the Symposium SIMPEP 2014.
  • Farmacologia Speciale. Prof. R, Maggio (UAQ): this theory supposes to support me next year, drug regimen design. As result, a talk given in the department of Medicine (UAQ) and an awarded paper in SIMPEP 2014, a journal extension was proposed by SIMPEP and a book proposal was submitted;
3. Summer Schools
  • Mathematical Models and Methods for Living Systems: it was a one-intensive week of studies, see http://web.math.unifi.it/users/cime/. Presentation of talk: On the mathematical modeling in gene expression estimation: an initial discussion on PBM and BM;
  • Systems Biology and Systems Medicine: precision Biotechnology and Therapies: this was a one-intensive week of studies and computer simulations, tutorial and lessons. See: http://ucbf.lakecomoschool.org/. Presentation of poster: On the mathematical modeling in gene expression estimation: an initial discussion on PBM and BM;
4. Short courses
  • Software Architecture: theory of how to design better software;
  • Convergence theory for observers: Necessary, and Sufficient conditions: theory on the design of state reconstruction systems;
  • Others: other courses were followed in the hope to find insights and methodologies.
5. Main references used
  • S Lenhart, J T Workman, Optimal Control Applied to biological models, Chapman & Hall/ CRC, Mathematical and Computational Biology Series, 2007;
  • Sara E Rosenbaum, basic pharmacokinetics and pharmacodynamics: an integrated textbook and computer simulations, John Wiley & Sons, 2011.
6. Most significant publications
  • JG Pires, R Maggio, C Manes, P Palumbo, On the importance of pharmacokinetics and pharmacodynamics in engineering sciences as an inter- and multidisciplinary field: an introductory analysis. SIMPEP 2014, Bauru (São Paulo, Brasil), Online: http://www.simpep.feb.unesp.br/anais_simpep.php?e=9
  • JG Pires, C Manes, P Palumbo, On the importance of optimal control theory in engineering sciences as a complementary and supplementary methodology to Operations Research: a case-study analysis. SIMPEP 2014, Bauru (São Paulo, Brasil), Online: http://www.simpep.feb.unesp.br/anais_simpep.php?e=9 

1. Introduction
The year of 2015, second year of the PhD pathway of the abovementioned student, was agreed to be dedicated to researches on the IASI-CNR (Gemelli Ospedale)[1]. The researches will consist of reading literatures and testing models published or propose new ones. The main topics is what we have called "The Big Glucose Model," which boils down to an attempt to enhance already existing mathematical and computational models for studying glucose control, in general the models are based just on insulin, the idea is to gather several different models based on other hormones or bio- molecules considered significant on the alteration of glucose levels in the human blood.
2. Courses to enroll
  • Identificazione dei Modelli e Analisi dei Dati: this is based on state space models;
  • Complementi di Automatica: this is based on kalman filter models and parameter stimation;
3. References
The references were not defined yet, it will be taken from an archive offered by De Gaetano, from the IASI-CNR Gemelli Ospedale.
A starting point could be:
  • P. Palumbo, S. Ditlevsen, A. Bertuzzi, A. De Gaetano, Mathematical modeling of the glucose-insulin system: A review, Mathematical Bioscience, 2013;
  • Ludovic J. Chassin, Malgorzata E. Wilinska, Roman Hovorka. Evaluation of glucose controllers in virtual environment: methodology and sample application, Artificial Intelligence in Medicine (2004) 32, 171—181
4. Final Remarks
Unfortunately a precise agenda for next year is complex, once it depends on my response to the project proposed by Andrea De Gaetano and the success on the research. In the first year I have finished all the prerequisites - two master-level disciplines and 18 credits of ad hoc activities - for avoiding conflicts with this part of my academic cycle.
5. Extra
One paper partially accepted: Biologia Sistêmica: um novo paradigma para as ciências biológicas e exatas “ou” Biologia Sistêmica e Inteligência Computacional. One paper invited to a journal, and three textbooks proposed to publish under invitation.



[1] CNR-IASI - Laboratorio di Biomatematica, UCSC – Largo A. Gemelli 8, 00168, Roma, Italy, Ph: +39 06 30155389       Fax: +39 06 3057845




Suggestion: Access the video from Youbube, then you will see a set of correlated videos, which can be very helpful. See scheme below.
Accessing Youtube from the current blog

Friday, October 10, 2014

Optimal Control in life sciences and medicine

Cover for the slides

Abstract: Optimal Control Applied to Life Sciences
Life Sciences might be seen as the connections between medicine, biology, mathematics, physics, and computer sciences. Further, optimal control might be defined as the extension of static optimization, or even as some comments, the new face of Variational Calculus.


In this talk we present several examples from life sciences analyzed with the support of optimal control. We might apply basically three approaches to optimal control problems, with their own weaknesses and strengthens: the Pontryagin’s Maximum Principle, Dynamic Programming, or Static Optimization. All the problems treated here were analyzed by the Pontryagin’s Maximum Principle.


The problems are solved using numerical schemes implemented in a computer. Topping the bill, we present two cases from a paper on process of publication: phototherapy for infants affected by neonatal jaundice and Feed-Forward Loop Network. We leave as future works comparisons with other approaches such as dynamic programming, or works on constraints on state space. Furthermore, we have concentrated on continuous-deterministic problems.  
 Keywords: Life Sciences, applied optimal control, numerical schemes, Runge-Kutta Method, forward-backward sweep method. 

Full PDF:

 
General Scheme for the numerical simulations

Scheme for the several ways to tackle numerically problems in optimal control theory

flowchart for the algorithms used in the numerical simulations

numerical simulations for the neonatal jaundice photo-therapy using optimal control theory


PS. I was biased mainly by

LENHART, S.; WORKMAN, J. T, Optimal Control Applied to biological models, Chapman & Hall/ CRC, Mathematical and Computational Biology Series, 2007.


See that is also a nice reference: 


Sebastian Anița, Viorel Arnăutu, Vincenzo Capasso, An introduction to optimal control problems in life sciences and economics: from mathematical models to numerical simulation with Matlab®, Modeling and Simulation in Science, Engineering and Technology, Birkhäuser, 2011. 

See Suzanne Lenhart homepage for several codes in Matlab. See that the codes are built independently of Matlab, they can be easily adapted to other languages.

 See for a simplified version of the codes used, in Portugal: 

 

Thursday, October 9, 2014

On the design of a molecular dynamics based model for studying receptor-receptor interactions: Systems Biology, Molecular Dynamics, and biomechanics



Content

Introduction

Methodological procedures

Theoretical Background

Receptors

Dimerization and ligand binding

Bioinformatics and mathematical modelling

G-protein-coupled receptor dynamics

The receptor–dimer cooperativity index

Single-molecule imaging revealed dynamic GPCR dimerization

Proposed model

Conclusions and Final remarks

References 

Download the full text: PDF.

Introduction

The pharmaceutical industries is likely to be amongst the most important and controversy ones. Issues present on the industries vary from misuse of advances such as not allowing drugs to reach the consumers or even manipulation of results. However, with no doubt , this is an extreme active area. Hot topics at the moment are: Systems Biology, Systems (bio) Medicine, P4 Medicine, and Systems Pharmacology.



The several scale to studying matter, from a physics viewpoint and from a biological viewpoint. For physics what matters is size rather organization. For physics the brain and a stone of the same size and mass is the same thing, but for biology one is a miracle of life and the second is a chunk of matter, useless.

 
The several levels of organization from human to genes, each level can be homeland for modeling, approaches that mixture them are in general called multiscales approaches


Scheme depicting the importance of receptors. A distal region can be controlled due to the concept of ligand and receptors




scheme for the methodology proposed for developing the software. the sphere supposes to represent the cell surface, whereas the dots are the dimers, or even monomers, that is, any clusters that can be considered a point, a node.



Videos used on the talk

  

This video was produced in 2012 in Gdansk as a warming up exercise in Continuous and Discrete simulations, taught by prof. Sergey Kshevetskii
Theoretical Physics Department of Immanuel Kant Russian
State University. The model is simple, just several particles in a box, with a potential between them, they are given an initial kick, there is no dissipation. 

This video was produced in Gdansk, as part of the lesson in classical simulations, by Winczewski Szymon, see Necking (nanowire)