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Articles 31 - 60 of 163

Full-Text Articles in Life Sciences

Effects Of Size, Caudal Autotomy, And Predator Kairomones On The Foraging Behavior Of Alleghany Mountain Dusky Salamanders (Desmognathus Ochrophaeus), Emilia A.R. Gildemeister, Wesley I. Payette, Aaron M. Sullivan Jan 2017

Effects Of Size, Caudal Autotomy, And Predator Kairomones On The Foraging Behavior Of Alleghany Mountain Dusky Salamanders (Desmognathus Ochrophaeus), Emilia A.R. Gildemeister, Wesley I. Payette, Aaron M. Sullivan

Faculty Publications - Department of Biological & Molecular Science

Prey must balance the conflicting demands of foraging and defensive behavior. Foraging under the threat of predation may be further complicated among species that engage in caudal autotomy, the loss of a portion of the tail at preformed breakage planes, because the tail may serve as an important energy storage organ and contribute to motility, culminating in a trade-off between foraging and predator avoidance. As a result of the advantages conferred by the presence of a tail, individuals that have recently undergone autotomy may be more motivated to forage despite elevated levels of threat indicated by predator kairomones. We used …


Collidoscope: An Improved Tool For Computing Collisional Cross Sections With The Trajectory Method, Simon A. Ewing, Micah T. Donor, Jesse W. Wilson, James S. Prell Jan 2017

Collidoscope: An Improved Tool For Computing Collisional Cross Sections With The Trajectory Method, Simon A. Ewing, Micah T. Donor, Jesse W. Wilson, James S. Prell

Faculty Publications - Department of Biological & Molecular Science

Ion Mobility-Mass Spectrometry (IM-MS) can be a powerful tool for determining structural information about ions in the gas phase, from small covalent analytes to large, unfolded, and/or denatured proteins and complexes. For large biomolecular ions, which may have a wide variety of possible gas-phase conformations and multiple charge sites, quantitative, physically explicit modeling of collisional cross sections (CCSs) for comparison to IMS data can be challenging and time-consuming. We present a “trajectory method” (TM) based CCS calculator, named “Collidoscope”, which utilizes parallel processing and optimized trajectory sampling, and implements both He and N2 as collision gas options. Also included is …


Beneficial Aerodynamic Effect Of Wing Scales On The Climbing Flight Of Butterflies, Nathan Slegers, Michael Heilman, Jacob Cranford, Amy Lang, John Yoder, Maria Laura Habegger Jan 2017

Beneficial Aerodynamic Effect Of Wing Scales On The Climbing Flight Of Butterflies, Nathan Slegers, Michael Heilman, Jacob Cranford, Amy Lang, John Yoder, Maria Laura Habegger

Faculty Publications - Biomedical, Mechanical, and Civil Engineering

It is hypothesized that butterfly wing scale geometry and surface patterning may function to improve aerodynamic efficiency. In order to investigate this hypothesis, a method to measure butterfly flapping kinematics optically over long uninhibited flapping sequences was developed. Statistical results for the climbing flight flapping kinematics of 11 butterflies, based on a total of 236 individual flights, both with and without their wing scales, are presented. Results show, that for each of the 11 butterflies, the mean climbing efficiency decreased after scales were removed. Data was reduced to a single set of differences of climbing efficiency using are paired t …


Toward An Improved Conceptual Understanding Of North American Tree Species Distributions, Paige E. Copenhaver-Parry Jan 2017

Toward An Improved Conceptual Understanding Of North American Tree Species Distributions, Paige E. Copenhaver-Parry

Faculty Publications - Department of Biological & Molecular Science

Species distributions have often been assumed to represent climatic limitations, yet recent evidence has challenged these assumptions and emphasized the potential importance of biotic interactions, dispersal limitation, and disturbance. Despite significant investigation into these factors, an integrated understanding of where and when they may be important is lacking. Here, we review evidence for the factors underlying the historical and contemporary distributions of North American tree species and argue that a cohesive conceptual framework must be informed by an understanding of species ecological and evolutionary history. We further demonstrate that available evidence offers little indication of a significant, independent influence of …


Hovering In The Heat: Effects Of Environmental Temperature On Heat Regulation In Foraging Hummingbirds, Don R. Powers, Kathleen M. Langland, Susan M. Wethington, Sean D. Powers, Catherine H. Graham, Bret W. Tobalske Jan 2017

Hovering In The Heat: Effects Of Environmental Temperature On Heat Regulation In Foraging Hummingbirds, Don R. Powers, Kathleen M. Langland, Susan M. Wethington, Sean D. Powers, Catherine H. Graham, Bret W. Tobalske

Faculty Publications - Department of Biological & Molecular Science

At high temperature (greater than 40°C) endotherms experience reduced passive heat dissipation (radiation, conduction and convection) and increased reliance on evaporative heat loss. High temperatures challenge flying birds due to heat produced by wing muscles. Hummingbirds depend on flight for foraging, yet inhabit hot regions. We used infrared thermography to explore how lower passive heat dissipation during flight impacts body-heat management in broad-billed (Cynanthus latirostris, 3.0 g), black-chinned (Archilochus alexandri, 3.0 g), Rivoli’s (Eugenes fulgens, 7.5 g) and blue-throated (Lampornis clemenciae, 8.0 g) hummingbirds in southeastern Arizona and calliope hummingbirds (Selasphorus calliope, 2.6 g) in Montana. Thermal gradients driving passive …


Fluorescence Induction Of Photosynthetic Bacteria, G. Spika, M. Kis, James L. Smart, P. Maroti Jan 2017

Fluorescence Induction Of Photosynthetic Bacteria, G. Spika, M. Kis, James L. Smart, P. Maroti

Faculty Publications - Department of Biological & Molecular Science

The kinetics of bacteriochlorophyll fluorescence in intact cells of the purple nonsulfur bacterium Rhodobacter sphaeroides were measured under continuous and pulsed actinic laser diode (808 nm wavelength and maximum 2 W light power) illumination on the micro- and millisecond timescale. The fluorescence induction curve was interpreted in terms of a combination of photochemical and triplet fluorescence quenchers and was demonstrated to be a reflection of redox changes and electron carrier dynamics. By adjustment of the conditions of single and multiple turnovers of the reaction center, we obtained 11 ms–1 and 120 μs–1 for the rate constants of cytochrome c2 3+ …


Using Whole-Group Metabolic Rate And Behaviour To Assess The Energetics Of Courtship In Red-Sided Garter Snakes, Christopher R. Friesen, Don Powers, Robert T. Mason Jan 2017

Using Whole-Group Metabolic Rate And Behaviour To Assess The Energetics Of Courtship In Red-Sided Garter Snakes, Christopher R. Friesen, Don Powers, Robert T. Mason

Faculty Publications - Department of Biological & Molecular Science

Reproductive effort is an important aspect of life history as reproductive success is arguably the most important component of fitness. Males tend to compete for access to females and, in the process, expend their energetic capital on mate searching, maleemale competition and courtship rather than directly on offspring. Red-sided garter snakes, Thamnophis sirtalis parietalis, are an exceptional model for studying energetic costs of courtship and mating as they fast during the spring mating season, which segregates the cost of energy acquisition from the cost of courtship and mating. However, measuring an individual male's metabolic rate during courtship is complicated by …


Species Interactions Weakly Modify Climate-Induced Tree Co-Occurrence Patterns, Paige E. Copenhaver-Parry Jan 2017

Species Interactions Weakly Modify Climate-Induced Tree Co-Occurrence Patterns, Paige E. Copenhaver-Parry

Faculty Publications - Department of Biological & Molecular Science

Aims: Species distributions are hypothesized to be underlain by a complex association of processes that span multiple spatial scales including biotic interactions, dispersal limitation, fine-scale resource gradients and climate. Species disequilibrium with climate may reflect the effects of non-climatic processes on species distributions, yet distribution models have rarely directly considered non-climatic processes. Here, we use a Joint Species Distribution Model (JSDM) to investigate the influence of non-climatic factors on species co-occurrence patterns and to directly quantify the relative influences of climate and alternative processes that may generate correlated responses in species distributions, such as species interactions, on tree co-occurrence patterns. …


Exploring The Interaction Of Drosophila Tdp-43 And The Type Ii Voltage-Gated Calcium Channel, Cacophony, In Regulating Motor Function And Behavior, Kayly M. Lembke, David B. Morton Jan 2017

Exploring The Interaction Of Drosophila Tdp-43 And The Type Ii Voltage-Gated Calcium Channel, Cacophony, In Regulating Motor Function And Behavior, Kayly M. Lembke, David B. Morton

Faculty Publications - Department of Biological & Molecular Science

Amyotrophic lateral sclerosis (ALS) is the most common adult onset motor neurodegenerative disease. The cause of the disease remains obscure, and as such there is no effective treatment or cure. Amyotrophic lateral sclerosis and other neurodegenerative diseases are frequently characterized by dysfunction of the RNA-binding protein, TDP-43. Using model systems to understand the mechanisms underlying TDP-43 dysfunction should accelerate identification of therapeutic targets. A recent report has shown that motor defects caused by the deletion of the Drosophila TDP-43 ortholog, tbph, are not driven by changes in the physiology at the neuromuscular junction. Rather, defective motor burst rhythmicity and coordination, …


Restoration Of Motor Defects Caused By Loss Of Drosophila Tdp-43 By Expression Of The Voltage-Gated Calcium Channel, Cacophony, In Central Neurons, Kayly M. Lembke, David B. Norton, Charles Scudder Jan 2017

Restoration Of Motor Defects Caused By Loss Of Drosophila Tdp-43 By Expression Of The Voltage-Gated Calcium Channel, Cacophony, In Central Neurons, Kayly M. Lembke, David B. Norton, Charles Scudder

Faculty Publications - Department of Biological & Molecular Science

Defects in the RNA-binding protein, TDP-43, are known to cause a variety of neurodegenerative diseases, including amyotrophic lateral sclerosis and frontotemporal lobar dementia. A variety of experimental systems have shown that neurons are sensitive to TDP-43 expression levels, yet the specific functional defects resulting from TDP-43 dysregulation have not been well described. Using the Drosophila TDP-43 ortholog TBPH, we previously showed that TBPH-null animals display locomotion defects as third instar larvae. Furthermore, loss of TBPH caused a reduction in cacophony, a Type II voltage-gated calcium channel, expression and that genetically restoring cacophony in motor neurons in TBPH mutant animals was …


Extended Protein Ions Are Formed By The Chain Ejection Model In Chemical Supercharging Electrospray Ionization, Micah T. Donor, Simon A. Ewing, Muhammad A. Zenaidee, William A. Donald, James S. Prell Jan 2017

Extended Protein Ions Are Formed By The Chain Ejection Model In Chemical Supercharging Electrospray Ionization, Micah T. Donor, Simon A. Ewing, Muhammad A. Zenaidee, William A. Donald, James S. Prell

Faculty Publications - Department of Biological & Molecular Science

Supercharging electrospray ionization can be a powerful tool for increasing charge states in mass spectra and generating unfolded ion structures, yet key details of its mechanism remain unclear. The structures of highly extended protein ions and the mechanism of supercharging were investigated using ion mobility-mass spectrometry. Head-to-tail-linked polyubiquitins (Ubq1−11) were used to determine size and charge state scaling laws for unfolded protein ions formed by supercharging while eliminating amino acid composition as a potential confounding factor. Collisional cross section was found to scale linearly with mass for these ions and several other monomeric proteins, and the maximum observed charge state …


Rhebi Expression In Embryonic And Postnatal Mouse, Qi Tian, James L. Smart, Joachim H. Clement, Yingming Wang, Alex Derkatch, Harald Schubert, Michael V. Danilchik, Daniel L. Marks, Lev M. Fedorov May 2016

Rhebi Expression In Embryonic And Postnatal Mouse, Qi Tian, James L. Smart, Joachim H. Clement, Yingming Wang, Alex Derkatch, Harald Schubert, Michael V. Danilchik, Daniel L. Marks, Lev M. Fedorov

Faculty Publications - Department of Biological & Molecular Science

Ras homolog enriched in brain (RHEB1) is a member within the superfamily of GTP-binding proteins encoded by the RAS oncogenes. RHEB1 is located at the crossroad of several important pathways including the insulin-signaling pathways and thus plays an important role in different physiological processes. To understand better the physiological relevance of RHEB1 protein, the expres- sion pattern of RHEB1 was analyzed in both embryonic (at E3.5–E16.5) and adult (1-month old) mice. RHEB1 immu- nostaining and X-gal staining were used for wild-type and Rheb1 gene trap mutant mice, respectively. These inde- pendent methods revealed similar RHEB1 expression pat- terns during both …


Three-Dimensional Simulation For Fast Forward Flight Of A Calliope Hummingbird, Jialei Song, Bret W. Tobalske, Don Powers, Tyson Hedrick, Haoxiang Luo May 2016

Three-Dimensional Simulation For Fast Forward Flight Of A Calliope Hummingbird, Jialei Song, Bret W. Tobalske, Don Powers, Tyson Hedrick, Haoxiang Luo

Faculty Publications - Department of Biological & Molecular Science

We present a computational study of flapping-wing aerodynamics of a calliope hummingbird (Selasphorus calliope) during fast forward flight. Three-dimensional wing kinematics were incorporated into the model by extracting time-dependent wing position from high-speed videos of the bird flying in a wind tunnel at 8.3 m s−1. The advance ratio, i.e. the ratio between flight speed and average wingtip speed, is around one. An immersed-boundary method was used to simulate flow around the wings and bird body. The result shows that both downstroke and upstroke in a wingbeat cycle produce significant thrust for the bird to overcome …


Scale-Dependent Contributions Of Abiotic And Biotic Factors To Tree Species Composition Patterns In The Us Rocky Mountains, Paige E. Copenhaver-Parry May 2016

Scale-Dependent Contributions Of Abiotic And Biotic Factors To Tree Species Composition Patterns In The Us Rocky Mountains, Paige E. Copenhaver-Parry

Faculty Publications - Department of Biological & Molecular Science

Scale-dependence is recognized as a ubiquitous feature of ecological systems. Ecologists have traditionally hypothesized a hierarchy of factors affecting the composition of ecological communities, with biotic interactions exerting a dominant influence at fine spatial scales, and abiotic factors such as climate driving patterns at broad spatial scales. However, the role of biotic interactions at macroecological scales has been increasingly questioned, with many ecologists hypothesizing that biotic interactions may have discernable effects on species distributions. Here, I evaluate the relative effects of climate and species interactions on composition patterns of tree species in the US Rocky Mountains. At fine spatial scales, …


Rheb1 Expression In Embryonic And Postnatal Mouse, Qi Tian, James L. Smart, Joachim H. Clement, Yingming Wang, Alex Derkatch, Harald Schubert, Michael V. Danilchik, Daniel L. Marks, Lev M. Federov May 2016

Rheb1 Expression In Embryonic And Postnatal Mouse, Qi Tian, James L. Smart, Joachim H. Clement, Yingming Wang, Alex Derkatch, Harald Schubert, Michael V. Danilchik, Daniel L. Marks, Lev M. Federov

Faculty Publications - Department of Biological & Molecular Science

Ras homolog enriched in brain (RHEB1) is a member within the superfamily of GTP-binding proteins encoded by the RAS oncogenes. RHEB1 is located at the crossroad of several important pathways including the insulin-signaling pathways and thus plays an important role in different physiological processes. To understand better the physiological relevance of RHEB1 protein, the expres-sion pattern of RHEB1 was analyzed in both embryonic (at E3.5–E16.5) and adult (1-month old) mice. RHEB1 immu-nostaining and X-gal staining were used for wild-type and Rheb1 gene trap mutant mice, respectively. These inde-pendent methods revealed similar RHEB1 expression pat-terns during both embryonic and postnatal developments. …


Flight Mechanics And Control Of Escape Manoeuvres In Hummingbirds. I. Flight Kinematics, Bo Cheng, Bret W. Tobalske, Donald R. Powers, Tyson L. Hedrick, Susan M. Wethington, George T.C. Chiu, Xinyan Deng Jan 2016

Flight Mechanics And Control Of Escape Manoeuvres In Hummingbirds. I. Flight Kinematics, Bo Cheng, Bret W. Tobalske, Donald R. Powers, Tyson L. Hedrick, Susan M. Wethington, George T.C. Chiu, Xinyan Deng

Faculty Publications - Department of Biological & Molecular Science

Hummingbirds are nature’s masters of aerobatic manoeuvres. Previous research shows that hummingbirds and insects converged evolutionarily upon similar aerodynamic mechanisms and kinematics in hovering. Herein, we use three-dimensional kinematic data to begin to test for similar convergence of kinematics used for escape flight and to explore the effects of body size upon manoeuvring. We studied four hummingbird species in North America including two large species (magnificent hummingbird, Eugenes fulgens, 7.8 g, and blue-throated hummingbird, Lampornis clemenciae, 8.0 g) and two smaller species (broad-billed hummingbird, Cynanthus latirostris, 3.4 g, and black-chinned hummingbirds Archilochus alexandri, 3.1 g). Starting from a steady hover, …


1-65-S-Algal Blooms: Algal Blooms Threatening Lake Chapala, R. Corban Harwood Jan 2016

1-65-S-Algal Blooms: Algal Blooms Threatening Lake Chapala, R. Corban Harwood

Faculty Publications - Department of Mathematics

This modeling scenario investigates the massive algal blooms that struck Lake Chapala, Mexico, starting in 1994. After reading a summary of articles written on the incidents, students are guided through the process of creating a first order differential equation from a verbal model of the factors and analyze the nonautonomous ODE using direction field, parameter evaluation, and exact solution computation to fully describe the population behavior. Students are expected to be familiar with the separable method and direction fields. Students will learn building and improving a model from qualitative descriptions, nondimensionalization, evaluating parameters, and how to use DFIELD software to …


Exploring Agricultural Production Systems And Their Fundamental Components With System Dynamics Modelling, Jeffrey P. Walters, David W. Archer, Gretchen F. Sassenrath, John R. Hendrickson, Jon D. Hanson, John M. Halloran, Peter Vadas, Vladimir J. Alarcon Jan 2016

Exploring Agricultural Production Systems And Their Fundamental Components With System Dynamics Modelling, Jeffrey P. Walters, David W. Archer, Gretchen F. Sassenrath, John R. Hendrickson, Jon D. Hanson, John M. Halloran, Peter Vadas, Vladimir J. Alarcon

Faculty Publications - Biomedical, Mechanical, and Civil Engineering

Agricultural production in the United States is undergoing marked changes due to rapid shifts in consumer demands, input costs, and concerns for food safety and environmental impact. Agricultural production systems are comprised of multidimensional components and drivers that interact in complex ways to influence production sustainability. In a mixed-methods approach, we combine qualitative and quantitative data to develop and simulate a system dynamics model that explores the systemic interaction of these drivers on the economic, environmental and social sustainability of agricultural production. We then use this model to evaluate the role of each driver in determining the differences in sustainability …


Winter Conditions Influence Biological Responses Of Migrating Hummingbirds, Catherine H. Graham, Sarah R. Supp, Donald R. Powers, Pieter Beck, Marisa C. W. Lim, Anusha Shankar, Scott Goetz, Susan M. Wethington Jan 2016

Winter Conditions Influence Biological Responses Of Migrating Hummingbirds, Catherine H. Graham, Sarah R. Supp, Donald R. Powers, Pieter Beck, Marisa C. W. Lim, Anusha Shankar, Scott Goetz, Susan M. Wethington

Faculty Publications - Department of Biological & Molecular Science

Conserving biological diversity given ongoing environmental changes requires the knowledge of how organisms respond biologically to these changes; however, we rarely have this information. This data deficiency can be addressed with coordinated monitoring programs that provide field data across temporal and spatial scales and with process-based models, which provide a method for predicting how species, in particular migrating species that face different conditions across their range, will respond to climate change. We evaluate whether environmental conditions in the wintering grounds of broad-tailed hummingbirds influence physiological and behavioral attributes of their migration. To quantify winter ground conditions, we used operative temperature …


The Relative Influences Of Climate And Competition On Tree Growth Along Montane Ecotones In The Rocky Mountains, Paige E. Copenhaver-Parry, Ellie Cannon Jan 2016

The Relative Influences Of Climate And Competition On Tree Growth Along Montane Ecotones In The Rocky Mountains, Paige E. Copenhaver-Parry, Ellie Cannon

Faculty Publications - Department of Biological & Molecular Science

Distribution shifts of tree species are likely to be highly dependent upon population performance at distribution edges. Understanding the drivers of aspects of performance, such as growth, at distribution edges is thus crucial to accurately predicting responses of tree species to climate change. Here, we use a Bayesian model and sensitivity analysis to partition the effects of climate and crowding, as a metric of competition, on radial growth of three dominant conifer species along montane ecotones in the Rocky Mountains. These ecotones represent upper and lower distribution edges of two species, and span the distribution interior of the third species. …


Do Community-Level Models Account For The Effects Of Biotic Interactions? A Comparison Of Community-Level And Species Distribution Modeling Of Rocky Mountain Conifers, Paige E. Copenhaver-Parry, Shannon Albeke, Daniel B. Tinker Jan 2016

Do Community-Level Models Account For The Effects Of Biotic Interactions? A Comparison Of Community-Level And Species Distribution Modeling Of Rocky Mountain Conifers, Paige E. Copenhaver-Parry, Shannon Albeke, Daniel B. Tinker

Faculty Publications - Department of Biological & Molecular Science

Community-level models (CLMs) aim to improve species distribution modeling (SDM) methods by attempting to explicitly incorporate the influences of interacting species. However, the ability of CLMs to appropriately account for biotic interactions is unclear. We applied CLM and SDM methods to predict the distributions of three dominant conifer tree species in the U.S. Rocky Mountains and compared CLM and SDM predictive accuracy as well as the ability of each approach to accurately reproduce species co-occurrence patterns. We specifically evaluated the performance of two statistical algorithms, MARS and CForest, within both CLM and SDM frameworks. Across all species, differences in SDM …


Flight Mechanics And Control Of Escape Manoeuvres In Hummingbirds. Ii. Aerodynamic Force Production, Flight Control And Performance Limitations, Bo Cheng, Bret W. Tobalske, Donald R. Powers, Tyson L. Hedrick, Yi Wang, Susan M. Wethington, George T.C. Chiu, Xinyan Deng Jan 2016

Flight Mechanics And Control Of Escape Manoeuvres In Hummingbirds. Ii. Aerodynamic Force Production, Flight Control And Performance Limitations, Bo Cheng, Bret W. Tobalske, Donald R. Powers, Tyson L. Hedrick, Yi Wang, Susan M. Wethington, George T.C. Chiu, Xinyan Deng

Faculty Publications - Department of Biological & Molecular Science

The superior manoeuvrability of hummingbirds emerges from complex interactions of specialized neural and physiological processes with the unique flight dynamics of flapping wings. Escape manoeuvring is an ecologically relevant, natural behaviour of hummingbirds, from which we can gain understanding into the functional limits of vertebrate locomotor capacity. Here, we extend our kinematic analysis of escape manoeuvres from a companion paper to assess two potential limiting factors of the manoeuvring performance of hummingbirds: (1) muscle mechanical power output and (2) delays in the neural sensing and control system. We focused on the magnificent hummingbird (Eugenes fulgens, 7.8 g) and the black-chinned …


Drift And Activity Responses Of Black Flies (Simulium Vittatum) In The Field: Influences Of Tactile And Injury-Released Stimuli From Simulated Predation, Aaron M. Sullivan, Elyse C. Johnson Jan 2016

Drift And Activity Responses Of Black Flies (Simulium Vittatum) In The Field: Influences Of Tactile And Injury-Released Stimuli From Simulated Predation, Aaron M. Sullivan, Elyse C. Johnson

Faculty Publications - Department of Biological & Molecular Science

Prey must manage threat from many types of predators; therefore, selection should favor sensory mechanisms that allow the refinement of defensive behavior. To assess responses to tactile and chemical stimuli related to predation, we observed drift and activity of larval black flies ( Simulium vittatum) to simulated predator contact intended to imitate benthic and drift predators as well as a combination of tactile and injury-released stimuli. In the field, larvae responded to tactile stimuli applied to the head with a higher frequency of curling and posterior abdominal segments with a higher frequency of drifting. Additionally, chemical cues from injured conspecifics …


Multiple Evolutionary Origins Of Ubiquitous Cu2+ And Zn2+ Binding In The S100 Protein Family, Lucas C. Wheeler, Micah T. Donor, James S. Prell, Michael J. Harms Jan 2016

Multiple Evolutionary Origins Of Ubiquitous Cu2+ And Zn2+ Binding In The S100 Protein Family, Lucas C. Wheeler, Micah T. Donor, James S. Prell, Michael J. Harms

Faculty Publications - Department of Biological & Molecular Science

The S100 proteins are a large family of signaling proteins that play critical roles in biology and disease. Many S100 proteins bind Zn2+, Cu2+, and/or Mn2+ as part of their biological functions; however, the evolutionary origins of binding remain obscure. One key question is whether divalent transition metal binding is ancestral, or instead arose independently on multiple lineages. To tackle this question, we combined phylogenetics with biophysical characterization of modern S100 proteins. We demonstrate an earlier origin for established S100 subfamilies than previously believed, and reveal that transition metal binding is widely distributed across the tree. Using isothermal titration calorimetry, …


Heat Dissipation During Hovering And Forward Flight In Hummingbirds, Don Powers, Bret W. Tobalske, J. Keaton Wilson, Keeley R. Corder Dec 2015

Heat Dissipation During Hovering And Forward Flight In Hummingbirds, Don Powers, Bret W. Tobalske, J. Keaton Wilson, Keeley R. Corder

Faculty Publications - Department of Biological & Molecular Science

Flying animals generate large amounts of heat, which must be dissipated to avoid overheating. In birds, heat dissipation is complicated by feathers, which cover most body surfaces and retard heat loss. To understand how birds manage heat budgets during flight, it is critical to know how heat moves from the skin to the external environment. Hummingbirds are instructive because they fly at speeds from 0 to more than 12ms−1, during which they transit from radiative to convective heat loss. We used infrared thermography and particle image velocimetry to test the effects of flight speed on heat loss from specific body …


Algae Population Self-Replenishment, R. Corban Harwood Jan 2015

Algae Population Self-Replenishment, R. Corban Harwood

Faculty Publications - Department of Mathematics

This modeling scenario investigates the massive algal blooms that struck Lake Chapala, Mexico, in 1994. After reading a summary of news articles on the incident, students create an ODE system model from a verbal description of the factors, visualize this system using an executable Java applet (PPLANE) to predict overall behavior, and then analyze the nonlinear system using the Jacobian matrix, eigenvalues, phase plane, and feasibility conditions on parameters to fully describe the system behavior. Students are expected to be familiar with systems of differential equations, equilibria, jacobian matrices, and eigenvalues. Students will learn modeling from qualitative descriptions, nondimensionalization, applying …


Citizen-Science Data Provides New Insight Into Annual And Seasonal Variation In Migration Patterns, S R. Supp, Frank A. La Sorte, Tina A. Cormier, Marisa C. W. Lim, Donald R. Powers, Susan M. Wethington, Scott Goetz, Catherine H. Graham Jan 2015

Citizen-Science Data Provides New Insight Into Annual And Seasonal Variation In Migration Patterns, S R. Supp, Frank A. La Sorte, Tina A. Cormier, Marisa C. W. Lim, Donald R. Powers, Susan M. Wethington, Scott Goetz, Catherine H. Graham

Faculty Publications - Department of Biological & Molecular Science

Current rates of global environmental and climate change pose potential challenges for migratory species that must cope with or adapt to new conditions and different rates of change across broad spatial scales throughout their annual life cycle. North American migratory hummingbirds may be especially sensitive to changes in environment and climate due to their extremely small body size, high metabolic rates, and dependence on nectar as a main resource. We used occurrence information from the eBird citizen-science database to track migratory movements of five North American hummingbird species (Archilochus alexandri, A. colubris, Selasphorus calliope, S. platycercus, and S. rufus) across …


Size Dependence In Non-Sperm Ejaculate Production Is Reflected In Daily Energy Expenditure And Resting Metabolic Rate, Christopher R. Friesen, Donald R. Powers, Paige E. Copenhaver-Parry, Robert T. Mason Jan 2015

Size Dependence In Non-Sperm Ejaculate Production Is Reflected In Daily Energy Expenditure And Resting Metabolic Rate, Christopher R. Friesen, Donald R. Powers, Paige E. Copenhaver-Parry, Robert T. Mason

Faculty Publications - Department of Biological & Molecular Science

The non-sperm components of an ejaculate, such as copulatory plugs, can be essential to male reproductive success. But the costs of these ejaculate components are often considered trivial. In polyandrous species, males are predicted to increase energy allocation to the production of non-sperm components, but this allocation is often condition dependent and the energetic costs of their production have never been quantified. Red-sided garter snakes (Thamnophis sirtalis parietalis) are an excellent model with which to quantify the energetic costs of non-sperm components of the ejaculate as they exhibit a dissociated reproductive pattern in which sperm production is temporally disjunct from …


A Simple Bioluminescent Method For Measuring D-Amino Acid Oxidase Activity, T. Spencer Bailey, Micah T. Donor, Sean P. Naughton, Michael D. Pluth Jan 2015

A Simple Bioluminescent Method For Measuring D-Amino Acid Oxidase Activity, T. Spencer Bailey, Micah T. Donor, Sean P. Naughton, Michael D. Pluth

Faculty Publications - Department of Biological & Molecular Science

D-Amino acid oxidase (DAO) plays important roles in regulating D-amino acid neurotransmitters and was recently identified as a key enzyme integral to hydrogen sulfide production from D-Cys. We report here the development of a simple biocompatible, bioluminescent method for measuring DAO activity based on the highly selective condensation of D-Cys with 6-hydroxy-2-cyanobenzothiazole (CBT-OH) to form D-luciferin.


Strad Pseudokinases Regulate Axogenesis And Lkb1 Stability, Biliana O. Veleva-Rotse, James L. Smart, Annette F. Baas, Benjamin Edmonds, Zi-Ming Zhao, Allyson Brown, Lillian R. Klug, Kelly Hansen, Gabrielle Rielly, Alexandria P. Gardner, Krishnaveni Subbiah, Eric A. Gaucher, Hans Clevers, Anthony P. Barnes Mar 2014

Strad Pseudokinases Regulate Axogenesis And Lkb1 Stability, Biliana O. Veleva-Rotse, James L. Smart, Annette F. Baas, Benjamin Edmonds, Zi-Ming Zhao, Allyson Brown, Lillian R. Klug, Kelly Hansen, Gabrielle Rielly, Alexandria P. Gardner, Krishnaveni Subbiah, Eric A. Gaucher, Hans Clevers, Anthony P. Barnes

Faculty Publications - Department of Biological & Molecular Science

No abstract provided.