Life Sciences Commons^™

Regenerative Ionic Currents And Bistability, Gregory D. Conradi Smith

Arts & Sciences Book Chapters

What every neuroscientist should know about the mathematical modeling of excitable cells. Combining empirical physiology and nonlinear dynamics, this text provides an introduction to the simulation and modeling of dynamic phenomena in cell biology and neuroscience. It introduces mathematical modeling techniques alongside cellular electrophysiology. Topics include membrane transport and diffusion, the biophysics of excitable membranes, the gating of voltage and ligand-gated ion channels, intracellular calcium signalling, and electrical bursting in neurons and other excitable cell types. It introduces mathematical modeling techniques such as ordinary differential equations, phase plane, and bifurcation analysis of single-compartment neuron models. With analytical and computational problem …

A Likelihood Ratio Test For Changes In Homeolog Expression Bias, Ronald D. Smith, Taliesin J. Kinser, Gregory D. Conradi Smith, Joshua R. Puzeyn

Arts & Sciences Articles

Background

Gene duplications are a major source of raw material for evolution and a likely contributor to the diversity of life on earth. Duplicate genes (i.e., homeologs, in the case of a whole genome duplication) may retain their ancestral function, sub- or neofunctionalize, or be lost entirely. A primary way that duplicate genes evolve new functions is by altering their expression patterns. Comparing the expression patterns of duplicate genes gives clues as to whether any of these evolutionary processes have occurred.

Results

We develop a likelihood ratio test for the analysis of the expression ratios of duplicate genes across two …

Trpm4 Ion Channels In Pre-Bo¨Tzinger Complex Interneurons Are Essential For Breathing Motor Pattern But Not Rhythm, Marina Cristina D. Picardo, Yae K. Sugimura, Kaitlyn E. Dorst, Prajkta S. Kallurkar, Victoria T. Akins, Xingru Ma, Ryoichi Teruyama, Romaine Guinamard, Kaiwen Kam, Margaret Saha, Christopher A. Del Negro

Arts & Sciences Articles

Inspiratory breathing movements depend on pre-Bötzinger complex (preBötC) interneurons that express calcium (Ca2+)-activated nonselective cationic current (ICAN) to generate robust neural bursts. Hypothesized to be rhythmogenic, reducing ICAN is predicted to slow down or stop breathing; its contributions to motor pattern would be reflected in the magnitude of movements (output). We tested the role(s) of ICAN using reverse genetic techniques to diminish its putative ion channels Trpm4 or Trpc3 in preBötC neurons in vivo. Adult mice transduced with Trpm4-targeted short hairpin RNA (shRNA) progressively decreased the tidal volume of breaths yet surprisingly increased breathing frequency, often followed by gasping and …

One Fish, Two Fish, Red Fish, Whose Fish? Subjects: Life Science, Environmental Science, Marine / Ocean Science, Shelby White

Reports

This activity invites students to assume the role of various stakeholders in fisheries management and actively discuss the influence of economics, ecology and human interactions in decision-making.

Students will demonstrate their argument for/against a certain regulation by participating as a specific stakeholder (i.e. commercial fisher, recreational fisher, scientists/researcher, environmental group, management agency, and citizen). Students will recognize that stakeholders tend to advocate based on their individual needs, often making it difficult for proposed policies to satisfy the needs of all stakeholders and achieve sustainability goals.

Expedition Sediments: Mud's Journey Through The Watershed. Subjects: Earth Science / Environmental Science Grades: 9-12, Jessie Turner

Reports

Expedition Sediments is a game-in-a-lesson that allows students to explore the movement of sediments through watersheds by moving around the classroom. This lesson explores how grains of estuarine mud and sand move throughout estuaries and coastal regions, with a focus on processes surrounding a highly populated estuary such as the Chesapeake Bay. By the end of the lesson, students will be able to explain how sediments are transported through an estuary, graph sediment residence times in different locations, and compare the timescales of different sediment transport processes.

Sequence Csi: The Nitrogen Cycle. Subjects: Life Science, Environmental Science, Marine/Ocean Science - Grades: 9-12, Stephanie Wilson

Reports

This lesson invites students to work together to identify a mystery DNA sample using state of the art biotechnology.

After identifying the organism, they can work with another group of students to hypothesize about how the different organisms are related to one another. Students will learn that the samples are connected through the nitrogen cycle! This gives students an introduction to scientific molecular techniques and environmental nitrogen cycling.

Invasive Species Research In Compensatory Wetland Mitigation: Investigating Plant Community Composition And Environmental Correlates With Three Invasive Plants, Dakota Hunter

Dissertations, Theses, and Masters Projects

Invasive plant species can alter natural communities and degrade ecosystem function, yet the factors influencing species invasion are poorly understood. Understanding how environmental factors affect plant invasion on compensatory wetland mitigation sites would allow wetland managers to approach invasive species management using a proactive approach (prior to invasion), thus minimizing the likelihood of invasive plants colonizing the system and degrading ecosystem function. In Chapter 1, I introduce the concepts and relevant literature used repeatedly in my project. In Chapter 2, I examine which key environmental factors are associated with altered plant community structure and invasive species prevalence on compensatory wetland …

Investigating The Functions Of Wetlands, Chesapeake Bay National Estuarine Research Reserve In Virginia

Reports

Grade level: 2-5

Subject area: Life Science

Students will perform two experiments using models of wetlands to learn about the ability of wetlands to prevent erosion, control flooding, and soak up pollutants. They will apply this knowledge in an activity using metaphors to describe a wetland.There is also an outdoor activity that may be added to teach students about a particular type of wetland, the saltmarsh, and adaptations for plants that live in those environments

Culturing Echinoderm Larvae Through Metamorphosis, Jason Hodin, Andreas Hayland, Annie Mercier, Bruno Pernet, David L. Cohen, Jean-Francois Hamel, Jonathan D. Allen, Justin S. Mcalister, Maria Byrne, Sophie B. George

Arts & Sciences Book Chapters

Echinoderms are favored study organisms not only in cell and developmental biology, but also physiology, larval biology, benthic ecology, population biology and paleontology, among other fields. However, many echinoderm embryology labs are not well-equipped to continue to rear the post-embryonic stages that result. This is unfortunate, as such labs are thus unable to address many intriguing biological phenomena, related to their own cell and developmental biology studies, that emerge during larval and juvenile stages. To facilitate broader studies of post-embryonic echinoderms, we provide here our collective experience rearing these organisms, with suggestions to try and pitfalls to avoid. Furthermore, we …