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Applied Mathematics

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Full-Text Articles in Life Sciences

Closed-Form Probability Distribution Of Number Of Infections At A Given Time In A Stochastic Sis Epidemic Model.Pdf, Michael Otunuga Sep 2019

Closed-Form Probability Distribution Of Number Of Infections At A Given Time In A Stochastic Sis Epidemic Model.Pdf, Michael Otunuga

Olusegun Michael Otunuga

We study the effects of external fluctuations in the transmission rate of certain diseases and how these affect the distribution of the number of infected individuals over time. To do this, we introduce random noise in the transmission rate in a deterministic SIS model and study how the number of infections changes over time. The objective of this work is to derive and analyze the closed form probability distribution of the number of infections at a given time in the resulting stochastic SIS epidemic model. Using the Fokker-Planck equation, we reduce the differential equation governing the number of infections to …

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Adoption Of Switchgrass Cultivation For Biofuel Under Uncertainty: A Discrete-Time Modeling Approach, Pralhad Burli, Eric Forgoston, Pankaj Lal, Lora Billings, Bernabas Wolde Jul 2017

Adoption Of Switchgrass Cultivation For Biofuel Under Uncertainty: A Discrete-Time Modeling Approach, Pralhad Burli, Eric Forgoston, Pankaj Lal, Lora Billings, Bernabas Wolde

Lora Billings

Production of biofuels from cellulosic sources, such as switchgrass, is being encouraged through mandates, incentives, and subsidies. However, uncertainty in future prices coupled with large establishment costs often inhibit their cultivation. Owing to their inability to incorporate uncertainty and dynamic decision-making, standard discounted cash flow techniques are ineffective for analyzing such investments. We formulate a discrete-time binomial framework to model output prices, allowing us to incorporate price uncertainty, stand age, and variable crop yields into the analytical framework. We analyze the feasibility of investments in switchgrass cultivation under varying price transition paths, evaluate the relationship between risk …

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Adoption Of Switchgrass Cultivation For Biofuel Under Uncertainty: A Discrete-Time Modeling Approach, Pralhad Burli, Eric Forgoston, Pankaj Lal, Lora Billings, Bernabas Wolde Jul 2017

Adoption Of Switchgrass Cultivation For Biofuel Under Uncertainty: A Discrete-Time Modeling Approach, Pralhad Burli, Eric Forgoston, Pankaj Lal, Lora Billings, Bernabas Wolde

Eric Forgoston

Production of biofuels from cellulosic sources, such as switchgrass, is being encouraged through mandates, incentives, and subsidies. However, uncertainty in future prices coupled with large establishment costs often inhibit their cultivation. Owing to their inability to incorporate uncertainty and dynamic decision-making, standard discounted cash flow techniques are ineffective for analyzing such investments. We formulate a discrete-time binomial framework to model output prices, allowing us to incorporate price uncertainty, stand age, and variable crop yields into the analytical framework. We analyze the feasibility of investments in switchgrass cultivation under varying price transition paths, evaluate the relationship between risk …

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Adoption Of Switchgrass Cultivation For Biofuel Under Uncertainty: A Discrete-Time Modeling Approach, Pralhad Burli, Eric Forgoston, Pankaj Lal, Lora Billings, Bernabas Wolde Jul 2017

Adoption Of Switchgrass Cultivation For Biofuel Under Uncertainty: A Discrete-Time Modeling Approach, Pralhad Burli, Eric Forgoston, Pankaj Lal, Lora Billings, Bernabas Wolde

Pankaj Lal

Production of biofuels from cellulosic sources, such as switchgrass, is being encouraged through mandates, incentives, and subsidies. However, uncertainty in future prices coupled with large establishment costs often inhibit their cultivation. Owing to their inability to incorporate uncertainty and dynamic decision-making, standard discounted cash flow techniques are ineffective for analyzing such investments. We formulate a discrete-time binomial framework to model output prices, allowing us to incorporate price uncertainty, stand age, and variable crop yields into the analytical framework. We analyze the feasibility of investments in switchgrass cultivation under varying price transition paths, evaluate the relationship between risk …

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An Agent-Based Modeling Approach To Determine Winter Survival Rates Of American Robins And Eastern Bluebirds, Samuel Iselin, Shannon Segin, Alex Capaldi Dec 2015

An Agent-Based Modeling Approach To Determine Winter Survival Rates Of American Robins And Eastern Bluebirds, Samuel Iselin, Shannon Segin, Alex Capaldi

Alex Capaldi

American Robins (Turdus migratorius) and Eastern Bluebirds (Sialia sialis) are two species of migratory thrushes that breed in Northwest Indiana but historically are uncommon during the winter season. These trends have changed recently, and both species are seen more abundantly during the winter. Recently invaded non-native fruiting plants continue to provide nutrients for the birds throughout the winter and may contribute to the increased avian populations during that time. To measure the effect these food sources contribute to thrush wintering habits, we created an agent-based computer model to simulate the birds' movement in Northwest Indiana along …

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Predicting Invasion Rates For Phragmites Australis, Rachel Nydegger, Jacob Duncan, James A. Powell Jun 2015

Predicting Invasion Rates For Phragmites Australis, Rachel Nydegger, Jacob Duncan, James A. Powell

Jacob P Duncan

In wetlands of Utah and southern Idaho as well as estuaries of the east coast, the ten-foot tall invasive grass Phragmites australis can be found near waterways, where it outcompetes native plants and degrades wildlife habitat. Phragmites australis is an obligate out-crossing plant that can spread sexually through seed disper- sal, or asexually via stolons and rhi- zomes (Kettenring and Mock 2012). Small patches are usually a single genetic individual, spreading vegetatively (and slowly) via runners; when patches become genetically diverse viable seeds are produced and invasion rates can be increase by an order of magnitude (Kettenring et al. 2011)

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Project-Based Collaborative Innovation For The Igeneration, James Gerry, Carl Heine May 2015

Project-Based Collaborative Innovation For The Igeneration, James Gerry, Carl Heine

Carl Heine

Social media provides powerful opportunities to create new learning communities. Online, project-based activities reach today's iGen students in ways they learn best, maximizing interaction and individualization through the use of free Web technologies such as CoolHub.IMSA. Discover ways to use networing tools to transform teaching and learning at your school.

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Multistrain Infections In Metapopulations, Sydney Garmer, Rachel Lynn, Dan Rossi, Alex Capaldi Dec 2014

Multistrain Infections In Metapopulations, Sydney Garmer, Rachel Lynn, Dan Rossi, Alex Capaldi

Alex Capaldi

Viruses and bacteria responsible for infectious diseases often mutate and are carried between geographical regions. We consider a mathematical model which begins to account for these factors. We assume two disjoint populations that only occasionally co-mingle and two strains of a disease present in these populations. Of interest are the equations describing the dynamics of this system, the conditions under which epidemics will occur, and the long term behavior of the system under various initial conditions. We fi#12;nd general conditions
under which a state of disease-free equilibrium is stable. Additionally, we #12;find existence of a biologically relevant equilibrium where two …

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Investigating Anthropogenic Mammoth Extinction With Mathematical Models, Michael Frank, Anneliese Slaton, Teresa Tinta, Alex Capaldi Dec 2014

Investigating Anthropogenic Mammoth Extinction With Mathematical Models, Michael Frank, Anneliese Slaton, Teresa Tinta, Alex Capaldi

Alex Capaldi

One extinction hypothesis of the Columbian mammoth (Mammuthus columbi), called overkill, theorizes that early humans overhunted the animal. We employ two different approaches to test this hypothesis mathematically: analyze the stability of the equilibria of a 2D ordinary differential equations (ODE) system and develop a metapopulation differential equations model. The 2D ODE system is a modified predator-prey model that also includes migration. The metapopulation model is a spatial expansion of the first model on a rectangular grid. Using this metapopulation system, we model the migration of humans into North America and the response in the mammoth population. These approaches show …

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Modelling And Parameter Identification For A Nonlinear Time-Delay System In Microbial Batch Fermentation, Chongyang Liu Dec 2012

Modelling And Parameter Identification For A Nonlinear Time-Delay System In Microbial Batch Fermentation, Chongyang Liu

Chongyang Liu

Mathematical modelling and parameter identification of a microbial batch fermentation process is considered in this paper. In view of the existence of time delays, a nonlinear time-delay system is firstly proposed to formulate the fermentation process. Some important properties are also discussed. Taking the errors between the computational values and the experimental data as the cost function, a parameter identification model subject to continuous state constraints and parameter constraints is then presented. To seek the optimal time delay and the optimal kinetic parameters, an improved differential evolution algorithm in conjunction with the constraint transcription technique is developed. Finally, numerical results …

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Statistical Research For The Kearny Marsh, Manfred Minimair, Juliana Newman Mar 2012

Statistical Research For The Kearny Marsh, Manfred Minimair, Juliana Newman

Manfred Minimair

Experimental data about the biological environment of the Kearny marsh, New Jersey, USA, is studied.

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The Effects Of 24 Weeks Of Resistance Training With Simultaneous Elastic And Free Weight Loading On Muscular Performance Of Novice Lifters, Todd C. Shoepe, David A. Ramirez, Robert J. Rovetti, David R. Kohler, Hawley C. Almstedt Aug 2011

The Effects Of 24 Weeks Of Resistance Training With Simultaneous Elastic And Free Weight Loading On Muscular Performance Of Novice Lifters, Todd C. Shoepe, David A. Ramirez, Robert J. Rovetti, David R. Kohler, Hawley C. Almstedt

Hawley Almstedt

The purpose of this investigation was to assess the effectiveness of variable resistance as provided through elastic plus free weight techniques in college aged males and females. Twenty novice lifters were randomly assigned to a traditional free weight only (6 males and 5 females) or elastic band plus free weight group (5 males and 5 females) and 9 more normally active controls (5 males and 4 females), were recruited to maintain normal activity for the duration of the study. No differences existed between control, free weight and elastic band at baseline for age, body height, body mass, body mass index, …

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The Effects Of 24 Weeks Of Resistance Training With Simultaneous Elastic And Free Weight Loading On Muscular Performance Of Novice Lifters, Todd C. Shoepe, David A. Ramirez, Robert J. Rovetti, David R. Kohler, Hawley C. Almstedt Aug 2011

The Effects Of 24 Weeks Of Resistance Training With Simultaneous Elastic And Free Weight Loading On Muscular Performance Of Novice Lifters, Todd C. Shoepe, David A. Ramirez, Robert J. Rovetti, David R. Kohler, Hawley C. Almstedt

Robert J. Rovetti

The purpose of this investigation was to assess the effectiveness of variable resistance as provided through elastic plus free weight techniques in college aged males and females. Twenty novice lifters were randomly assigned to a traditional free weight only (6 males and 5 females) or elastic band plus free weight group (5 males and 5 females) and 9 more normally active controls (5 males and 4 females), were recruited to maintain normal activity for the duration of the study. No differences existed between control, free weight and elastic band at baseline for age, body height, body mass, body mass index, …

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The Effects Of 24 Weeks Of Resistance Training With Simultaneous Elastic And Free Weight Loading On Muscular Performance Of Novice Lifters, Todd C. Shoepe, David A. Ramirez, Robert J. Rovetti, David R. Kohler, Hawley C. Almstedt Aug 2011

The Effects Of 24 Weeks Of Resistance Training With Simultaneous Elastic And Free Weight Loading On Muscular Performance Of Novice Lifters, Todd C. Shoepe, David A. Ramirez, Robert J. Rovetti, David R. Kohler, Hawley C. Almstedt

Todd Shoepe

The purpose of this investigation was to assess the effectiveness of variable resistance as provided through elastic plus free weight techniques in college aged males and females. Twenty novice lifters were randomly assigned to a traditional free weight only (6 males and 5 females) or elastic band plus free weight group (5 males and 5 females) and 9 more normally active controls (5 males and 4 females), were recruited to maintain normal activity for the duration of the study. No differences existed between control, free weight and elastic band at baseline for age, body height, body mass, body mass index, …

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Is The Curvature Of The Flagellum Involved In The Apparent Cooperativity Of The Dynein Arms Along The "9+2" Axoneme?, Christian Cibert, Andrei Ludu Jun 2010

Is The Curvature Of The Flagellum Involved In The Apparent Cooperativity Of The Dynein Arms Along The "9+2" Axoneme?, Christian Cibert, Andrei Ludu

Andrei Ludu

In a recent study [Cibert, 2008. Journal of Theoretical Biology, 253, 74-89], by assuming that the walls of microtubules are involved in cyclic compression/dilation equilibriums as a consequence of their cyclic curvature of the axoneme, it was proposed that local adjustments of spatial frequencies of both dynein arms and beta-tubulin monomers facing series create propagation of joint probability waves of interaction (JPI) between these two necessary partners. Modeling the occurrence of these interactions along the entire length of an axoneme between each outer doublet pair (without programming any cooperative dialog between the molecular complexes) and the cyclic attachment of two …

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Modeling In Microbial Batch Culture And Its Parameter Identification, Zhaohua Gong, Chongyang Liu, Enmin Feng Nov 2009

Modeling In Microbial Batch Culture And Its Parameter Identification, Zhaohua Gong, Chongyang Liu, Enmin Feng

Chongyang Liu

In this paper, the nonlinear dynamical system of batch fermentation is investigated in the bioconversion of glycerol to 1,3-propanediol(1,3-PD) by Klebsiella pneumoniae. Taking account of the kinetic behavior and experimental results in the batch cultures, we propose a two-stage dynamical system to formulate the fermentation process. Then some properties of the proposed system are proved. In view of the big errors between observations and numerical simulation results, we subsequently establish a parameter identification model to identify parameters in the system. The identifiability of the model is also discussed. Finally, in order to find the optimal parameters of the identification model, …

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Multiple Loci Within The Major Histocompatibility Complex Confer Risk Of Psoriasis, Bing-Jian Feng, Liang-Dan Sun, Razieh Soltani-Arabshahi, Anne M. Bowcock, Rajan P. Nair, Philip Stuart, James T. Elder, Steven J. Schrodi, Ann B. Begovich, Goncalo R. Abecasis, Xue-Jun Zhang, Kristina P. Callis Duffin, Gerald G. Krueger, David E. Goldgar Jul 2009

Multiple Loci Within The Major Histocompatibility Complex Confer Risk Of Psoriasis, Bing-Jian Feng, Liang-Dan Sun, Razieh Soltani-Arabshahi, Anne M. Bowcock, Rajan P. Nair, Philip Stuart, James T. Elder, Steven J. Schrodi, Ann B. Begovich, Goncalo R. Abecasis, Xue-Jun Zhang, Kristina P. Callis Duffin, Gerald G. Krueger, David E. Goldgar

Steven J Schrodi

Psoriasis is a common inflammatory skin disease characterized by thickened scaly red plaques. Previously we have performed a genome-wide association study (GWAS) on psoriasis with 1,359 cases and 1,400 controls, which were genotyped for 447,249 SNPs. The most significant finding was for SNP rs12191877, which is in tight linkage disequilibrium with HLA-Cw*0602, the consensus risk allele for psoriasis. However, it is not known whether there are other psoriasis loci within the MHC in addition to HLA-C. In the present study, we searched for additional susceptibility loci within the human leukocyte antigen (HLA) region through in-depth analyses of the GWAS data; …

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Genome-Wide Scan Reveals Association Of Psoriasis With Il-23 And Nf-B Pathways, Rajan P. Nair, Kristina C. Duffin, Cynthia Helms, Jun Ding, Philip E. Stuart, David Goldgar, Johann E. Gudjonsson, Yun Li, Trilokraj Tejasvi, Bing-Jiag Feng, Andreas Ruether, Stefan Schreiber, Michael Weichenthal, Dafna Gladman, Proton Rahman, Steven J. Schrodi, Sampath Prahalad, Stephen L. Guthery, Judith Fischer, Wilson Liao, Pui-Yan Kwok, Alan Menter, G Mark Lathrop, Carol A. Wise, Ann B. Begovich, John J. Voorhees, James T. Elder, Gerald G. Krueger, Anne M. Bowcock, Goncalo R. Abecasis Dec 2008

Genome-Wide Scan Reveals Association Of Psoriasis With Il-23 And Nf-B Pathways, Rajan P. Nair, Kristina C. Duffin, Cynthia Helms, Jun Ding, Philip E. Stuart, David Goldgar, Johann E. Gudjonsson, Yun Li, Trilokraj Tejasvi, Bing-Jiag Feng, Andreas Ruether, Stefan Schreiber, Michael Weichenthal, Dafna Gladman, Proton Rahman, Steven J. Schrodi, Sampath Prahalad, Stephen L. Guthery, Judith Fischer, Wilson Liao, Pui-Yan Kwok, Alan Menter, G Mark Lathrop, Carol A. Wise, Ann B. Begovich, John J. Voorhees, James T. Elder, Gerald G. Krueger, Anne M. Bowcock, Goncalo R. Abecasis

Steven J Schrodi

Psoriasis is a common immune-mediated disorder that affects the skin, nails and joints. To identify psoriasis susceptibility loci, we genotyped 438,670 SNPs in 1,409 psoriasis cases and 1,436 controls of European ancestry. We followed up 21 promising SNPs in 5,048 psoriasis cases and 5,041 controls. Our results provide strong support for the association of at least seven genetic loci and psoriasis (each with combined P < 5 10-8). Loci with confirmed association include HLA-C, three genes involved in IL-23 signaling (IL23A, IL23R, IL12B), two genes that act downstream of TNF- and regulate NF-B signaling (TNIP1, TNFAIP3) and two genes involved in the modulation of Th2 immune responses (IL4, IL13). Although the proteins encoded in these loci are known to interact biologically, we found no evidence for epistasis between associated SNPs. Our results expand the catalog of genetic loci implicated in psoriasis susceptibility and suggest priority targets for study in other auto-immune disorders.

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A Fine Mapping Theorem To Refine Results From Association Genetics Studies, Steven J. Schrodi Dec 2008

A Fine Mapping Theorem To Refine Results From Association Genetics Studies, Steven J. Schrodi

Steven J Schrodi

No abstract provided.

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A Large-Scale Rheumatoid Arthritis Genetic Study Identifies Association At Chr 9q33.2, Steven J. Schrodi May 2007

A Large-Scale Rheumatoid Arthritis Genetic Study Identifies Association At Chr 9q33.2, Steven J. Schrodi

Steven J Schrodi

No abstract provided.

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Using Math In Cell Biology: A Tale Of Two Channel Types, Borbala Mazzag Mar 2007

Using Math In Cell Biology: A Tale Of Two Channel Types, Borbala Mazzag

Borbala Mazzag

No abstract provided.

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Computational Modeling Of Calcium Dynamics Near Heterogeneous Release Sites, Borbala Mazzag, Zachary Cooper, Michael Greenwood Dec 2006

Computational Modeling Of Calcium Dynamics Near Heterogeneous Release Sites, Borbala Mazzag, Zachary Cooper, Michael Greenwood

Borbala Mazzag

Background: Calcium is known to play an important role in many physiological
processes, such as egg fertilization and heart muscle functions.
Several recent theoretical studies ([4], [1]) investigated calcium dynamics
near so-called release sites – clusters of calcium-regulated channels on
the intracellular calcium stores. Interest in the synchronized openings of
channels within a release site has increased because these openings are
thought to be the building blocks of global calcium events.
Methods: We conduct computational studies of the effect of heterogeneity
in the make-up of the release site on the resulting calcium dynamics.
We introduce heterogeneity into the model of …

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The Localized Dynamics Of A Ca2+Channel (30-Minute Talk), Borbala Mazzag, Christoper Tignanelli, Gregory D. Smith Aug 2006

The Localized Dynamics Of A Ca2+Channel (30-Minute Talk), Borbala Mazzag, Christoper Tignanelli, Gregory D. Smith

Borbala Mazzag

No abstract provided.

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Graduate Colloquium, Borbala Mazzag Aug 2005

Graduate Colloquium, Borbala Mazzag

Borbala Mazzag

No abstract provided.

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Using Math In Cell Biology How Do Calcium Channels Work?, Borbala Mazzag Feb 2004

Using Math In Cell Biology How Do Calcium Channels Work?, Borbala Mazzag

Borbala Mazzag

No abstract provided.

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A Model For Shear Stress Sensing And Transmission In Vascular Endothelial Cells, Borbala Mazzag, John S. Tamaresis, Abdul Barakat May 2003

A Model For Shear Stress Sensing And Transmission In Vascular Endothelial Cells, Borbala Mazzag, John S. Tamaresis, Abdul Barakat

Borbala Mazzag

 Arterial endothelial cell (EC) responsiveness to flow is essential for normal vascular function and plays a role in the development of atherosclerosis. EC flow responses may involve sensing of the mechanical stimulus at the cell surface with subsequent transmission via cytoskeleton to intracellular transduction sites. We had previously modeled flow-induced deformation of EC-surface flow sensors represented as viscoelastic materials with standard linear solid behavior (Kelvin bodies). In the present article, we extend the analysis to arbitrary networks of viscoelastic structures connected in series and/or parallel. Application of the model to a system of two Kelvin bodies in parallel reveals that …

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A Mathematical Model Of Bacterial Aerotaxis, Borbala Mazzag, Alex Mogilner Sep 2002

A Mathematical Model Of Bacterial Aerotaxis, Borbala Mazzag, Alex Mogilner

Borbala Mazzag

No abstract provided.

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Mathematical Models In Biology, Borbala Mazzag Dec 2001

Mathematical Models In Biology, Borbala Mazzag

Borbala Mazzag

No abstract provided.

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Reflexive Autopoietic Systems Theory, Kent D. Palmer Dec 1999

Reflexive Autopoietic Systems Theory, Kent D. Palmer

Kent D. Palmer

Exploring the Meta-systems of Emergent Worlds

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