Research progress, new features, and version release announcements

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• November 2018
  Our member symposium at ESA in Vancouver, Density Dependence, Community Genetics, and Resistance Evolution, was a great time thanks to all the interesting folks presenting. Talks ranged from empirical measurement of density-dependent survival to theoretical studies of effects on resistance evolution and the consequences of different modeling approaches. You can view the presentations by Jeannette Martinez and Nick Friedenberg in the downloads section of our IRM page.
   

• September 2018
  The member symposium at the upcoming  Entomological Society of America conference in Vancouver, BC, Density Dependence, Community Genetics, and Resistance Evolution has shaped up to be a great collection of speakers addressing the fundamentals of understanding and leveraging density dependence for insect resistance management. Presentations will include empirical ecological studies, evolutionary modeling, and new gene drive technology.
   

• February 2018
  The 2018 Entomology conference in Vancouver, BC, should be great. Nick Friedenberg, Mike Caprio, and Jeannette Martinez are organizing a member symposium on density dependence and resistance evolution. Nick will talk about the challenge of linking models with experimental data on density dependent survival.
   

• December 2017
  Look for a new paper featuring modeling backed by RAMAS IRM.

  • Martinez, J.C., M.A. Caprio, and N.A. Friedenberg. 2018. Density dependence and growth rate: evolutionary effects on resistance development to Bt (Bacillus thuringiensis). Journal of Economic Entomology 111: 382-390.

  • Request reprint
     

• November 2017
  Nick Friedenberg attended the 2017 national conference of the Entomological Society of America and presented results from a collaboration with Jeannette Martinez of EPA and Michael Caprio of Mississippi State University. The study included simulations of a hypothetical insect pest using Dr. Martinez's model. Results were validated by reproducing the model in RAMAS IRM. The research explored the influence of density dependence and population growth rate on resistance evolution. Findings suggest that these ecological characteristics should be given as much consideration as trait efficacy when developing a resistance management plan.
   

• April 2017
  We participated in the 2017 onRamp Insurance Conference in Chicago, IL. We are exploring whether crop insurers could help promote better resistance management compliance by using RAMAS IRM to price resistance risk.
   

• October 2016
  We had a great time giving our workshop on IRM at the 2016 Student Conference on Conservation Science, held at the American Museum of Natural History in New York City. Participants got an overview of  issues and concepts in insect resistance management. We also used RAMAS IRM to illustrate how models are used to address the main questions in the field, using the example of structured versus blended refuge. Participants will get a one-month license to explore the program on their own. As in past years, Applied Biomathematics helped with poster judging and provided free copies of its conservation software as prizes for the best quantitative poster and oral presentation.
   

• September 2016
  Applied Biomathematics welcomes Vincent Keenan, a visiting scholar from the University of Liverpool. Keenan, who's work centers on the dynamics of range expansions and ecological invasions, will help to implement optimized numerical methods for the simulation of dispersal.
  
  Nick Friedenberg attended the International Congress of Entomology this month to present work using RAMAS IRM to investigate whether it is safe to use simple gene pool models in models of resistance governed by two or more loci. This question is particularly important as the number of Bt traits in the landscape increases and individual plants express pyramids of two or more traits. The results generally suggest caution when using gene pool models. By neglecting the presence of linkage disequilibrium under strong selection, they may overestimate the time to resistance by as much as 300%. However, under biologically reasonable combinations of toxicity to susceptible and heterozygotic pests, the overestimation error is typically less than 50%. As pyramids become more complex, gene pool models may be more appropriate, giving lower error especially for mid- to low-dose traits in combination. However, redundancy among traits can greatly increase the degree to which gene pool models overestimate durability. Slides for the presentation can be obtained from the Downloads section of the RAMAS IRM page.
  
  Nick also collaborated on a study of resistance hotspot remediation with Jeannette Martinez and Michael Caprio of Mississippi State University. Martinez presented this follow-up to the group's oral paper given last year at the 2015 annual conference of the Entomological Society of America. Slides for the 2015 talk can be obtained from the Downloads section of the RAMAS IRM page.
   

• June 2016
  Applied Biomathematics congratulates Senior Scientist Nick Friedenberg for procuring a Phase II Small Business Innovation Research award from USDA-NIFA. The grant supports research and development leading to an expansion in the number of genes RAMAS IRM can simulate, along with other additions to the program and validation through reproduction of published models.
   

• March 2016
  We are preparing to offer a workshop on RAMAS IRM at the 2016 Student Conference on Conservation Science, held at the American Museum of Natural History in New York City. Participants will receive an overview of  issues and concepts in insect resistance management. We will use RAMAS IRM to illustrate how models are used to address the main questions in the field. Participants will get a one-month license to explore the program on their own. As in past years, Applied Biomathematics will help with poster judging and will provide free copies of its conservation software for the best quantitative poster and oral presentation. We encourage graduate students in conservation biology not to miss this energetic meeting.
   

• November 2015
  Nick Friedenberg used a development version of RAMAS IRM to contribute model results for his presentation this year at the Entomology conference. Coauthors Janneatte Martinez and Michael Caprio provided independent modeling on remediation of resistance for the symposium, "Worldwide Resistance to Bt-toxins: Causes, Consequences, Cures?".
   

• July 2015
  RAMAS IRM 2.1.4 released.

  Revised Hardy-Weinberg option verified to produce the same result as the full gametotypic algorithm for single-locus models, even with complex adult life history. This version also introduces automatic updates.
   

• June 2015
  RAMAS IRM 2.1.2 released.

  In addition to bug fixes, the generational time step has now been completely implemented. Selection of this option causes phenological information to be ignored, allowing a mechanism to quickly test the sensitivity of model results to the often complex parameterization of adult life history.
   

• May 2015
  Applied Biomathematics has received a Phase I SBIR award from USDA-NIFA to expand the capabilities of RAMAS IRM.
   

• March 2015
  RAMAS IRM 2.1.1 released. Refuge location can now be fixed, randomized, or alternating. Density dependence options now include the Maynard Smith and Slatkin (1973) function, which is a form used commonly in IRM modeling papers (e.g., Crowder and Onstad 2005; Pan, et al. 2011). Density dependence can also be set to only occur above a specified population density, as is suggested for western corn rootworm (Hibbard, et al. 2010). Minor bug fixes to the interface improve stability for complicated life histories.
   

• December 2014
  RAMAS IRM 2.1 released. This version introduces significant performance gains for landscapes that are large relative to dispersal distance. Version 2.1 also addresses a number of bugs in the 2.0 release.
   

• September 2014
  RAMAS IRM 2.0 is now available. Version 2.0 inherits the upgraded features of 1.1, including 4 loci, fitness costs for resistance, and the ability to convert between common modeling approaches with a single click. Completely new for 2.0 is an extensive list of inputs for specifying adult phenology, including the timing of mating, dispersal, and oviposition as well as sex- and genotype-specific developmental delays. On a technical level, the program now preserves information on natal environment for accurate crop-specific phenology and fecundity of dispersing females in multi-crop landscapes. Version 2.0 also features sex-specific dispersal distances.
   

• March 2014
  Pricing announced for RAMAS IRM, including affordable academic site licensing and special student prices to encourage use in undergraduate education and graduate research.
   

• February 2014
  A new version of RAMAS IRM is coming! New features include 4 loci, fitness costs for resistance, and a suite of controls for converting between common modeling approaches with a single click. Look for RAMAS IRM version 1.1 on sale soon.
   

• Febraury 2014
  Applied Biomathematics is collaborating with Michael Caprio (Project Lead, Mississippi State), Joe Spencer (University of Illinois), and Tom Sappington (USDA). The project integrates resistance models with new data on short- and long-distance corn rootworm movement.
   

• November 2013
  The NIMBioS investigative workshop on modeling pesticide resistance evolution was a success. Organized by Nicholas Friedenberg of Applied Biomathematics and David Crowder of Washington State University, the workshop was co-funded by NSF, USDA, and Homeland Security through the National Institute for Mathematical and Biological Synthesis. The workshop drew a diverse group of participants at all career stages from academia and industry for a two-day intensive discussion of resistance modeling. View some of the presentations online here.
   

• November 2013
  Nicholas Friedenberg presents at the Entomological Society of America annual conference in Austin, TX. "The surprising importance of modeling abundance when assessing PIP durability." The talk explores how the scale of density dependence affects adaptive rates through modification of relative fitness. Concepts are demonstrated using results from RAMAS IRM.
   

• November 2013
  Kevin Shoemaker presents at the Entomological Society of America annual conference in Austin, TX. "Assessing durability of Bt crops where insect resistance genes are linked." The talk reviews important published work demonstrating how linkage decreases the durability of pyramided pesticides. But Kevin goes further, using RAMAS IRM to show that gene pool models in common use, where the population is assumed to be in Hardy-Weinberg equilibrium after mating, can drastically overestimate the durability of pyramids even when genes are unlinked.
   

• August 2013
  The NIMBioS investigative workshop on modeling pesticide resistance evolution has a new blog.
   

• July 2013
  New features in RAMAS IRM: 1) turn your abundance-based model into a frequency-based model with one click of the mouse. 2) Embed calls to RAMAS IRM in other programs or scripts, such as R, Matlab, or Java. Model parameters and output are available via XML.
   

• June 2013
  Evolution 2013: Simulations run in RAMAS IRM suggest that the rate of adaptation to Bt crops is driven by the absolute, not relative, fitness of heterozygotes in abundance-based models.
   

• June 2013
  The NIMBioS investigative workshop on pesticide resistance is now open for applications. The application deadline is August 12, 2013. For more information about the workshop and how to apply, click here.
   

• April 2013
  Pesticide resistance workshop announced. Nicholas Friedenberg of Applied Biomathematics and David Crowder of Washington State University won approval for their workshop proposal to the National Institute for Mathematical and Biological Synthesis. The workshop will be held in the fall of 2013.
   

• February 2013
  The beta is now available! Download a free evaluation copy and help guide the development of RAMAS IRM with your feedback.
   

• November 2012
  RAMAS IRM unveiled at Entomology 2012 in Knoxville, TN.

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