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Automated Requirements Analysis For A Molecular Watchdog Timer, Samuel J. Ellis, Eric R. Henderson, Titus H. Klinge, James I. Lathrop, Jack H. Lutz, Robyn R. Lutz, Divita Mathur, Andrew S. Miner 2017 Iowa State University

Automated Requirements Analysis For A Molecular Watchdog Timer, Samuel J. Ellis, Eric R. Henderson, Titus H. Klinge, James I. Lathrop, Jack H. Lutz, Robyn R. Lutz, Divita Mathur, Andrew S. Miner

Robyn Lutz

Dynamic systems in DNA nanotechnology are often programmed using a chemical reaction network (CRN) model as an intermediate level of abstraction. In this paper, we design and analyze a CRN model of a watchdog timer, a device commonly used to monitor the health of a safety critical system. Our process uses incremental design practices with goal-oriented requirements engineering, software verification tools, and custom software to help automate the software engineering process. The watchdog timer is comprised of three components: an absence detector, a threshold filter, and a signal amplifier. These components are separately designed and verified, and only then composed ...


Requirements Analysis For A Product Family Of Dna Nanodevices, Robyn R. Lutz, Jack H. Lutz, James I. Lathrop, Titus H. Klinge, Divita Mathur, D. M. Stull, Taylor G. Bergquist, Eric R. Henderson 2017 Iowa State University

Requirements Analysis For A Product Family Of Dna Nanodevices, Robyn R. Lutz, Jack H. Lutz, James I. Lathrop, Titus H. Klinge, Divita Mathur, D. M. Stull, Taylor G. Bergquist, Eric R. Henderson

Robyn Lutz

DNA nanotechnology uses the information processing capabilities of nucleic acids to design self-assembling, programmable structures and devices at the nanoscale. Devices developed to date have been programmed to implement logic circuits and neural networks, capture or release specific molecules, and traverse molecular tracks and mazes. Here we investigate the use of requirements engineering methods to make DNA nanotechnology more productive, predictable, and safe. We use goal-oriented requirements modeling to identify, specify, and analyze a product family of DNA nanodevices, and we use PRISM model checking to verify both common properties across the family and properties that are specific to individual ...


Engineering And Verifying Requirements For Programmable Self-Assembling Nanomachines, Robyn Lutz, Jack Lutz, James Lathrop, Titus Klinge, Eric Henderson, Davita Mathur, Dalia Abo Sheasha 2017 Iowa State University

Engineering And Verifying Requirements For Programmable Self-Assembling Nanomachines, Robyn Lutz, Jack Lutz, James Lathrop, Titus Klinge, Eric Henderson, Davita Mathur, Dalia Abo Sheasha

Robyn Lutz

We propose an extension of van Lamsweerde's goal-oriented requirements engineering to the domain of programmable DNA nanotechnology. This is a domain in which individual devices (agents) are at most a few dozen nanometers in diameter. These devices are programmed to assemble themselves from molecular components and perform their assigned tasks. The devices carry out their tasks in the probabilistic world of chemical kinetics, so they are individually error-prone. However, the number of devices deployed is roughly on the order of a nanomole (a 6 followed by fourteen 0s), and some goals are achieved when enough of these agents achieve ...


Ncbi-Blast Programs Optimization On Xsede Resources For Sustainable Aquaculture, Arun S. Seetharam, Antonio Gomez, Catherine M. Purcell, John R. Hyde, Philip D. Blood, Andrew J. Severin 2017 Iowa State University

Ncbi-Blast Programs Optimization On Xsede Resources For Sustainable Aquaculture, Arun S. Seetharam, Antonio Gomez, Catherine M. Purcell, John R. Hyde, Philip D. Blood, Andrew J. Severin

Andrew Severin

The development of genomic resources of non-model organisms is now becoming commonplace as the cost of sequencing continues to decrease. The Genome Informatics Facility in collaboration with the Southwest Fisheries Science Center (SWFSC), NOAA is creating these resources for sustainable aquaculture in Seriola lalandi. Gene prediction and annotation are common steps in the pipeline to generate genomic resources, which are computationally intense and time consuming. In our steps to create genomic resources for Seriola lalandi, we found BLAST to be one of our most rate limiting steps. Therefore, we took advantage of our XSEDE Extended Collaborative Support Services (ECSS) to ...


Crispr-Cas9 Nuclear Dynamics And Target Recognition In Living Cells, Hanhui Ma, Li-Chun Tu, Ardalan Naseri, Maximiliaan Huisman, Shaojie Zhang, David Grünwald, Thoru Pederson 2017 University of Massachusetts Medical School

Crispr-Cas9 Nuclear Dynamics And Target Recognition In Living Cells, Hanhui Ma, Li-Chun Tu, Ardalan Naseri, Maximiliaan Huisman, Shaojie Zhang, David Grünwald, Thoru Pederson

David Grünwald

The bacterial CRISPR-Cas9 system has been repurposed for genome engineering, transcription modulation, and chromosome imaging in eukaryotic cells. However, the nuclear dynamics of clustered regularly interspaced short palindromic repeats (CRISPR)-associated protein 9 (Cas9) guide RNAs and target interrogation are not well defined in living cells. Here, we deployed a dual-color CRISPR system to directly measure the stability of both Cas9 and guide RNA. We found that Cas9 is essential for guide RNA stability and that the nuclear Cas9-guide RNA complex levels limit the targeting efficiency. Fluorescence recovery after photobleaching measurements revealed that single mismatches in the guide RNA seed ...


Estimation Of The True Evolutionary Distance Under The Fragile Breakage Model., Nikita Alexeev, Max A Alekseyev 2017 George Washington University

Estimation Of The True Evolutionary Distance Under The Fragile Breakage Model., Nikita Alexeev, Max A Alekseyev

Computational Biology Institute

BACKGROUND: The ability to estimate the evolutionary distance between extant genomes plays a crucial role in many phylogenomic studies. Often such estimation is based on the parsimony assumption, implying that the distance between two genomes can be estimated as the rearrangement distance equal the minimal number of genome rearrangements required to transform one genome into the other. However, in reality the parsimony assumption may not always hold, emphasizing the need for estimation that does not rely on the rearrangement distance. The distance that accounts for the actual (rather than minimal) number of rearrangements between two genomes is often referred to ...


Isolation And Comparative Genomic Analysis Of Final Third Of Satis Genome, Kelly Hartigan, Nicole Curnutt, Matthew McDermut 2017 Washington University in St. Louis

Isolation And Comparative Genomic Analysis Of Final Third Of Satis Genome, Kelly Hartigan, Nicole Curnutt, Matthew Mcdermut

Undergraduate Research Symposium Posters

A highly novel Streptomyces phage, Satis, was isolated from a direct environmental sample collected from outside Danforth House on the Washington University campus. Satis infects bacterial species Streptomyces lividans producing pinpoint, cloudy plaques less than 1mm in diameter. Electron microscope data shows rare atypical physical features. Rather than the common octahedral capsid shape, Satis has a prolate head with visible cross-linked hexagonal protein structure and average measurements of 285 nm by 47 nm with a long, flexible tail measuring 268 nm. Upon sequencing, it was found that Satis contains the longest phage genome discovered to date through the SEA-PHAGE program ...


Identification Of Conserved Gene Structures And Carboxy-Terminal Motifs In The Myb Gene Family Of Arabidopsis And Oryza Sativa L. Ssp. Indica, Cizhong Jiang, Xun Gu, Thomas Peterson 2017 Iowa State University

Identification Of Conserved Gene Structures And Carboxy-Terminal Motifs In The Myb Gene Family Of Arabidopsis And Oryza Sativa L. Ssp. Indica, Cizhong Jiang, Xun Gu, Thomas Peterson

Thomas Peterson

Background Myb proteins contain a conserved DNA-binding domain composed of one to four repeat motifs (referred to as R0R1R2R3); each repeat is approximately 50 amino acids in length, with regularly spaced tryptophan residues. Although the Myb proteins comprise one of the largest families of transcription factors in plants, little is known about the functions of most Myb genes. Here we use computational techniques to classify Myb genes on the basis of sequence similarity and gene structure, and to identify possible functional relationships among subgroups of Myb genes from Arabidopsis and rice (Oryza sativa L. ssp. indica). Results This study analyzed ...


Using Mathematical Models Of Biological Processes In Genome-Wide Association Studies Of Psychiatric Disorders, Amy Cochran 2017 University of Michigan-Ann Arbor

Using Mathematical Models Of Biological Processes In Genome-Wide Association Studies Of Psychiatric Disorders, Amy Cochran

Biology and Medicine Through Mathematics Conference

No abstract provided.


Generation Of Tandem Direct Duplications By Reversed-Ends Transposition Of Maize Ac Elements, Jianbo Zhang, Tao Zuo, Thomas A. Peterson 2017 Iowa State University

Generation Of Tandem Direct Duplications By Reversed-Ends Transposition Of Maize Ac Elements, Jianbo Zhang, Tao Zuo, Thomas A. Peterson

Thomas Peterson

Tandem direct duplications are a common feature of the genomes of eukaryotes ranging from yeast to human, where they comprise a significant fraction of copy number variations. The prevailing model for the formation of tandem direct duplications is non-allelic homologous recombination (NAHR). Here we report the isolation of a series of duplications and reciprocal deletions isolated de novo from a maize allele containing two Class II Ac/Ds transposons. The duplication/deletion structures suggest that they were generated by alternative transposition reactions involving the termini of two nearby transposable elements. The deletion/duplication breakpoint junctions contain 8 bp target site ...


Automated Requirements Analysis For A Molecular Watchdog Timer, Samuel J. Ellis, Eric R. Henderson, Titus H. Klinge, James I. Lathrop, Jack H. Lutz, Robyn R. Lutz, Divita Mathur, Andrew S. Miner 2017 Iowa State University

Automated Requirements Analysis For A Molecular Watchdog Timer, Samuel J. Ellis, Eric R. Henderson, Titus H. Klinge, James I. Lathrop, Jack H. Lutz, Robyn R. Lutz, Divita Mathur, Andrew S. Miner

Eric Henderson

Dynamic systems in DNA nanotechnology are often programmed using a chemical reaction network (CRN) model as an intermediate level of abstraction. In this paper, we design and analyze a CRN model of a watchdog timer, a device commonly used to monitor the health of a safety critical system. Our process uses incremental design practices with goal-oriented requirements engineering, software verification tools, and custom software to help automate the software engineering process. The watchdog timer is comprised of three components: an absence detector, a threshold filter, and a signal amplifier. These components are separately designed and verified, and only then composed ...


Requirements Analysis For A Product Family Of Dna Nanodevices, Robyn R. Lutz, Jack H. Lutz, James I. Lathrop, Titus H. Klinge, Divita Mathur, D. M. Stull, Taylor G. Bergquist, Eric R. Henderson 2017 Iowa State University

Requirements Analysis For A Product Family Of Dna Nanodevices, Robyn R. Lutz, Jack H. Lutz, James I. Lathrop, Titus H. Klinge, Divita Mathur, D. M. Stull, Taylor G. Bergquist, Eric R. Henderson

Eric Henderson

DNA nanotechnology uses the information processing capabilities of nucleic acids to design self-assembling, programmable structures and devices at the nanoscale. Devices developed to date have been programmed to implement logic circuits and neural networks, capture or release specific molecules, and traverse molecular tracks and mazes. Here we investigate the use of requirements engineering methods to make DNA nanotechnology more productive, predictable, and safe. We use goal-oriented requirements modeling to identify, specify, and analyze a product family of DNA nanodevices, and we use PRISM model checking to verify both common properties across the family and properties that are specific to individual ...


Engineering And Verifying Requirements For Programmable Self-Assembling Nanomachines, Robyn Lutz, Jack Lutz, James Lathrop, Titus Klinge, Eric Henderson, Davita Mathur, Dalia Abo Sheasha 2017 Iowa State University

Engineering And Verifying Requirements For Programmable Self-Assembling Nanomachines, Robyn Lutz, Jack Lutz, James Lathrop, Titus Klinge, Eric Henderson, Davita Mathur, Dalia Abo Sheasha

Eric Henderson

We propose an extension of van Lamsweerde's goal-oriented requirements engineering to the domain of programmable DNA nanotechnology. This is a domain in which individual devices (agents) are at most a few dozen nanometers in diameter. These devices are programmed to assemble themselves from molecular components and perform their assigned tasks. The devices carry out their tasks in the probabilistic world of chemical kinetics, so they are individually error-prone. However, the number of devices deployed is roughly on the order of a nanomole (a 6 followed by fourteen 0s), and some goals are achieved when enough of these agents achieve ...


Complex Dna Nanostructures From Oligonucleotide Ensembles, Divita Mathur, Eric R. Henderson 2017 Iowa State University

Complex Dna Nanostructures From Oligonucleotide Ensembles, Divita Mathur, Eric R. Henderson

Eric Henderson

The first synthetic DNA nanostructures were created by self-assembly of a small number of oligonucleotides. Introduction of the DNA origami method provided a new paradigm for designing and creating two- and three-dimensional DNA nanostructures by folding a large single-stranded DNA and ‘stapling’ it together with a library of oligonucleotides. Despite its power and wide-ranging implementation, the DNA origami technique suffers from some limitations. Foremost among these is the limited number of useful single-stranded scaffolds of biological origin. This report describes a new approach to creating large DNA nanostructures exclusively from synthetic oligonucleotides. The essence of this approach is to replace ...


Programmable Dna Nanosystem For Molecular Interrogation, Davita Mathur, Eric R. Henderson 2017 United States Naval Research Laboratory

Programmable Dna Nanosystem For Molecular Interrogation, Davita Mathur, Eric R. Henderson

Eric Henderson

We describe a self-assembling DNA-based nanosystem for interrogating molecular interactions. The nanosystem contains a rigid supporting dumbbell-shaped frame, a cylindrical central core, and a mobile ring that is coaxial with the core. Motion of the ring is influenced by several control elements whose force-generating capability is based on the transition of single-stranded DNA to double-stranded DNA. These forces can be directed to act in opposition to adhesive forces between the ring and the frame thereby providing a mechanism for molecular detection and interrogation at the ring-frame interface. As proof of principle we use this system to evaluate base stacking adhesion ...


Hybridization Dynamics Of A Newly Discovered Parrotfish Swarm In The Tropical Eastern Pacific, Robert Barron 2017 Bowdoin College

Hybridization Dynamics Of A Newly Discovered Parrotfish Swarm In The Tropical Eastern Pacific, Robert Barron

Honors Projects

Hybrid zones and their dynamics are important in the understanding of the genetic basis of reproductive isolation and speciation. This study seeks to investigate the hybridization dynamics of a Scarus hybrid swarm within the Tropical Eastern Pacific (TEP) that includes four phenotypically distinct species: S. perrico, S. ghobban, S. rubroviolaceus, and S. compressus. Genetic and population structure analyses of four nuclear loci and a mitochondrial locus revealed that one of the four species, S. compressus, was the result of two different hybrid crosses: S. perricoS. rubroviolaceus and S. perricoS. ghobban. A NewHybrids model indicated that most of the ...


Transcriptomic Effects Of Dispersed Oil In A Non-Model Decapod Crustacean, Hernan Vazquez-Miranda, Brent Thoma, Juliet Wong, Darryl Felder, Keith A. Crandall, Heather Bracken-Grissom 2017 George Washington University

Transcriptomic Effects Of Dispersed Oil In A Non-Model Decapod Crustacean, Hernan Vazquez-Miranda, Brent Thoma, Juliet Wong, Darryl Felder, Keith A. Crandall, Heather Bracken-Grissom

Computational Biology Institute

Background. Oil spills are major environmental disasters. Dispersants help control spills, as they emulsify oil into droplets to speed bioremediation. Although dispersant toxicity is controversial, the genetic consequences and damages of dispersed oil exposure are poorly understood. We used RNA-seq to measure gene expression of flatback mudcrabs (Eurypanopeus depressus, Decapoda, Brachyura, Panopeidae) exposed to dispersed oil.

Methods. Our experimental design included two control types, oil-only, and oil-dispersant treatments with three replicates each. We prepared 100 base pair-ended libraries from total RNA and sequenced them in one Illumina HiSeq2000 lane. We assembled a reference transcriptome with all replicates per treatment, assessed ...


Using Imputation As A Method Of Improving Genetic Data Analysis, Kimberly Diaz Perez 2017 Georgia State University

Using Imputation As A Method Of Improving Genetic Data Analysis, Kimberly Diaz Perez

Georgia State Undergraduate Research Conference

No abstract provided.


Dna Barcoding Analysis Of Seafood Accuracy In Washington, D.C. Restaurants, David Stern, Eduardo Castro Nallar, Jason Rathod, Keith A. Crandall 2017 George Washington University

Dna Barcoding Analysis Of Seafood Accuracy In Washington, D.C. Restaurants, David Stern, Eduardo Castro Nallar, Jason Rathod, Keith A. Crandall

Computational Biology Institute

In Washington D.C., recent legislation authorizes citizens to test if products are properly represented and, if they are not, to bring a lawsuit for the benefit of the general public. Recent studies revealing the widespread phenomenon of seafood substitution across the United States make it a fertile area for consumer protection testing. DNA barcoding provides an accurate and cost-effective way to perform these tests, especially when tissue alone is available making species identification based on morphology impossible. In this study, we sequenced the 5′ barcoding region of the Cytochrome Oxidase I gene for 12 samples of vertebrate and invertebrate ...


Involvement Of A Putative Intercellular Signal-Recognizing G Protein-Coupled Receptor In The Engulfment Of Salmonella By The Protozoan Tetrahymena, P. N. Agbedanu, M. T. Brewer, T. A. Day, M. J. Kimber, K. L. Anderson, S. K. Rasmussen, M. A. Rasmussen, S. A. Carlson 2017 Iowa State University

Involvement Of A Putative Intercellular Signal-Recognizing G Protein-Coupled Receptor In The Engulfment Of Salmonella By The Protozoan Tetrahymena, P. N. Agbedanu, M. T. Brewer, T. A. Day, M. J. Kimber, K. L. Anderson, S. K. Rasmussen, M. A. Rasmussen, S. A. Carlson

Matthew T. Brewer

In an effort to investigate the molecular basis of protozoa engulfment-mediated hypervirulence of Salmonella in cattle, we evaluated protozoan G protein-coupled receptors (GPCRs) as transducers of Salmonella engulfment by the model protozoanTetrahymena. Our laboratory previously demonstrated that non-pathogenic protozoa (including Tetrahymena) engulf Salmonella and then exacerbate its virulence in cattle, but the mechanistic details of the phenomenon are not fully understood. GPCRs were investigated since these receptors facilitate phagocytosis of particulates byTetrahymena, and a GPCR apparently modulates bacterial engulfment for the pathogenic protozoan Entamoeba histolytica. A database search identified three putative Tetrahymena GPCRs, based on sequence homologies and ...


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