279 research outputs found
Multiobjective optimization to a TB-HIV/AIDS coinfection optimal control problem
We consider a recent coinfection model for Tuberculosis (TB), Human
Immunodeficiency Virus (HIV) infection and Acquired Immunodeficiency Syndrome
(AIDS) proposed in [Discrete Contin. Dyn. Syst. 35 (2015), no. 9, 4639--4663].
We introduce and analyze a multiobjective formulation of an optimal control
problem, where the two conflicting objectives are: minimization of the number
of HIV infected individuals with AIDS clinical symptoms and coinfected with
AIDS and active TB; and costs related to prevention and treatment of HIV and/or
TB measures. The proposed approach eliminates some limitations of previous
works. The results of the numerical study provide comprehensive insights about
the optimal treatment policies and the population dynamics resulting from their
implementation. Some nonintuitive conclusions are drawn. Overall, the
simulation results demonstrate the usefulness and validity of the proposed
approach.Comment: This is a preprint of a paper whose final and definite form is with
'Computational and Applied Mathematics', ISSN 0101-8205 (print), ISSN
1807-0302 (electronic). Submitted 04-Feb-2016; revised 11-June-2016 and
02-Sept-2016; accepted for publication 15-March-201
Optimal Control and Sensitivity Analysis of a Fractional Order TB Model
A Caputo fractional-order mathematical model for the transmission dynamics of
tuberculosis (TB) was recently proposed in [Math. Model. Nat. Phenom. 13
(2018), no. 1, Art. 9]. Here, a sensitivity analysis of that model is done,
showing the importance of accuracy of parameter values. A fractional optimal
control (FOC) problem is then formulated and solved, with the rate of treatment
as the control variable. Finally, a cost-effectiveness analysis is performed to
assess the cost and the effectiveness of the control measures during the
intervention, showing in which conditions FOC is useful with respect to
classical (integer-order) optimal control.Comment: This is a preprint of a paper whose final and definite form is with
'Statistics Opt. Inform. Comput.', Vol. 7, No 2 (2019). See
[http://www.IAPress.org]. Submitted 09/Sept/2018; Revised 10/Dec/2018;
Accepted 11/Dec/2018. arXiv admin note: text overlap with arXiv:1801.09634,
arXiv:1810.0690
Disease diagnosis in smart healthcare: Innovation, technologies and applications
To promote sustainable development, the smart city implies a global vision that merges artificial intelligence, big data, decision making, information and communication technology (ICT), and the internet-of-things (IoT). The ageing issue is an aspect that researchers, companies and government should devote efforts in developing smart healthcare innovative technology and applications. In this paper, the topic of disease diagnosis in smart healthcare is reviewed. Typical emerging optimization algorithms and machine learning algorithms are summarized. Evolutionary optimization, stochastic optimization and combinatorial optimization are covered. Owning to the fact that there are plenty of applications in healthcare, four applications in the field of diseases diagnosis (which also list in the top 10 causes of global death in 2015), namely cardiovascular diseases, diabetes mellitus, Alzheimer’s disease and other forms of dementia, and tuberculosis, are considered. In addition, challenges in the deployment of disease diagnosis in healthcare have been discussed
A multiobjective optimization approach to statistical mechanics
Optimization problems have been the subject of statistical physics
approximations. A specially relevant and general scenario is provided by
optimization methods considering tradeoffs between cost and efficiency, where
optimal solutions involve a compromise between both. The theory of Pareto (or
multi objective) optimization provides a general framework to explore these
problems and find the space of possible solutions compatible with the
underlying tradeoffs, known as the {\em Pareto front}. Conflicts between
constraints can lead to complex landscapes of Pareto optimal solutions with
interesting implications in economy, engineering, or evolutionary biology.
Despite their disparate nature, here we show how the structure of the Pareto
front uncovers profound universal features that can be understood in the
context of thermodynamics. In particular, our study reveals that different
fronts are connected to different classes of phase transitions, which we can
define robustly, along with critical points and thermodynamic potentials. These
equivalences are illustrated with classic thermodynamic examples.Comment: 14 pages, 8 figure
Clustering Algorithms: Their Application to Gene Expression Data
Gene expression data hide vital information required to understand the biological process that takes place in a particular organism in relation to its environment. Deciphering the hidden patterns in gene expression data proffers a prodigious preference to strengthen the understanding of functional genomics. The complexity of biological networks and the volume of genes present increase the challenges of comprehending and interpretation of the resulting mass of data, which consists of millions of measurements; these data also inhibit vagueness, imprecision, and noise. Therefore, the use of clustering techniques is a first step toward addressing these challenges, which is essential in the data mining process to reveal natural structures and iden-tify interesting patterns in the underlying data. The clustering of gene expression data has been proven to be useful in making known the natural structure inherent in gene expression data, understanding gene functions, cellular processes, and subtypes of cells, mining useful information from noisy data, and understanding gene regulation. The other benefit of clustering gene expression data is the identification of homology, which is very important in vaccine design. This review examines the various clustering algorithms applicable to the gene expression data in order to discover and provide useful knowledge of the appropriate clustering technique that will guarantee stability and high degree of accuracy in its analysis procedure
Optimal strategies for fighting persistent bugs
Some microbial organisms are known to randomly slip into and out of
hibernation, irrespective of environmental conditions [1]. In a (genetically)
uniform population a typically very small subpopulation becomes metabolically
inactive whereas the majority subpopulation remains active and grows. Bacteria
such as E. coli, Staphylococcus aureus (MRSA-superbug), Mycobacterium
tuberculosis, and Pseudomonas aeruginosa [1-3] show persistence. It can render
bacteria less vulnerable in adverse environments [1, 4, 5] and their effective
eradication through medication more difficult [2, 3, 6]. Here we show that
medication treatment regimes may have to be modified when persistence is taken
into account and characterize optimal approaches assuming that the total
medication dose is constrained. The determining factors are cumulative
toxicity, eradication power of the medication and bacterial response
timescales. Persistent organisms have to be fought using tailored eradication
strategies which display two fundamental characteristics. Ideally, the
treatment time should be significantly longer than in the case of persistence
with the medication uniformly spread out over time; however, if treatment time
has to be limited, then the application of medication has to be concentrated
towards the beginning and end of the treatment. These findings deviate from
current clinical practice, and may therefore help to optimize and simplify
treatments. Our use of multi-objective optimization [7] to map out the optimal
strategies can be generalized to other related problems.Comment: 6 pages, 6 figure
Literature Review - the vaccine supply chain
Vaccination is one of the most effective ways to prevent the outbreak of an infectious disease. This medical intervention also brings about many logistical quest
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