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Multiple Subject Barycentric Discriminant Analysis (Musubada): How To Assign Scans To Categories Without Using Spatial Normalization, Hervé Abdi, Lynne J. Williams, Andrew C. Connolly, M. Ida Gobbini

Dartmouth Scholarship

We present a new discriminant analysis (DA) method called Multiple Subject Barycentric Discriminant Analysis (MUSUBADA) suited for analyzing fMRI data because it handles datasets with multiple participants that each provides different number of variables (i.e., voxels) that are themselves grouped into regions of interest (ROIs). Like DA, MUSUBADA (1) assigns observations to predefined categories, (2) gives factorial maps displaying observations and categories, and (3) optimally assigns observations to categories. MUSUBADA handles cases with more variables than observations and can project portions of the data table (e.g., subtables, which can represent participants or ROIs) on the factorial maps. Therefore MUSUBADA can …

The Effect Of The Female Athlete Triad On Performance: Both Physiologically And Psychologically, Constance Darlington

Honors Theses

The female athlete triad is a condition that is composed of an interaction of three separate disorders: low energy intake due to the presence of an eating disorder or disordered eating, menstrual dysfunction, such as, oligomenorrhea or amenorrhea, and osteoporosis. Separately, each disorder can affect performance; however, when the disorders are combined, the consequences are magnified. The female triad has a profound effect on an athlete's performance both physiologically and psychologically. The female athlete triad can affect any female athlete; however, it is more prevalent among the athletes that specialize in aesthetic sports or sports that emphasize leanness, for example, …

Septin Phosphorylation And Coiled-Coil Domains Function In Cell And Septin Ring Morphology In The Filamentous Fungus Ashbya Gossypii, Rebecca A. Meseroll, Patricia Occhipinti, Amy S. Gladfelter

Dartmouth Scholarship

Septins are a class of GTP-binding proteins conserved throughout many eukaryotes. Individual septin subunits associate with one another and assemble into heteromeric complexes that form filaments and higher-order structures in vivo. The mechanisms underlying the assembly and maintenance of higher-order structures in cells remain poorly understood. Septins in several organisms have been shown to be phosphorylated, although precisely how septin phosphorylation may be contributing to the formation of high-order septin structures is unknown. Four of the five septins expressed in the filamentous fungus, Ashbya gossypii, are phosphorylated, and we demonstrate here the diverse roles of these phosphorylation sites …

A Novel Method For Comparative Analysis Of Retinal Specialization Traits From Topographic Maps, Bret A. Moore, Jason M. Kamilar, Shaun P. Collin, Olaf R. P. Bininda-Emonds, Nathaniel J. Dominy, Margaret I. Hall, Christopher P. Hessy, Sonke Johnsen, Thomas J. Lisney, Ellis R. Loew, Gillian Moritz

Dartmouth Scholarship

Abstract Vertebrates possess different types of retinal specializations that vary in number, size, shape, and position in the retina. This diversity in retinal configuration has been revealed through topographic maps, which show variations in neuron density across the retina. Although topographic maps of about 300 vertebrates are available, there is no method for characterizing retinal traits quantitatively. Our goal is to present a novel method to standardize information on the position of the retinal specializations and changes in retinal ganglion cell (RGC) density across the retina from published topographic maps. We measured the position of the retinal specialization using two …

The Role Of Rate Of Force Development On Vertical Jump Performance, Christopher Mclellan, Dale Lovell, Gregory Gass

Chris McLellan

The purpose of this study was to examine a) the relationship between rate of force development (RFD) and vertical jump (VJ) performance during a counter movement jump (CMJ), and b) the reliability of RFD recorded during the CMJ and squat jump (SJ) forms of the VJ. Twenty-three physically active men aged 23 ± 3.9 years participated in the study. Subjects completed 3 unloaded CMJ and 3 unloaded SJ in random order on a force plate. The RFD was measured during CMJ and SJ movements with vertical jump displacement (VJD) measured simultaneously during the CMJ only. Subjects incorporated arm swing to …

A Physiological Trait-Based Approach To Predicting The Responses Of Species To Experimental Climate Warming, Sarah E. Diamond, Lauren M. Nichols, Neil Mccoy, Christopher Hirsch, Shannon L. Pelini, Nathan J. Sanders, Aaron M. Ellison, Nicholas J. Gotelli, Robert R. Dunn

College of Arts and Sciences Faculty Publications

Physiological tolerance of environmental conditions can influence species-level responses to climate change. Here, we used species-specific thermal tolerances to predict the community responses of ant species to experimental forest-floor warming at the northern and southern boundaries of temperate hardwood forests in eastern North America. We then compared the predictive ability of thermal tolerance vs. correlative species distribution models (SDMs) which are popular forecasting tools for modeling the effects of climate change. Thermal tolerances predicted the responses of 19 ant species to experimental climate warming at the southern site, where environmental conditions are relatively close to the ants' upper thermal limits. …

Cold Season Physiology Of Arctic Plants, Jonathan G. Moser

FIU Electronic Theses and Dissertations

The cold season in the Arctic extends over eight to nine months during which ecosystem gas exchange and water balance of arctic plants have been largely unexplored. The overall objective of this thesis was to examine two critical gaps in our knowledge about tundra cold season processes – ecosystem respiration at very low temperatures and water uptake during the winter-spring transition. I determined the temperature response of ecosystem respiration of tundra monoliths down to temperatures as low as can be expected under snow-covered conditions (-15 °C). Temperature responses fit the Arrhenius function well with Q₁₀ values over the range …

A Comparison Of Asynchronous And Synchronous Arm Cranking During The Wingate Test, Dale Lovell, Dale Mason, Elias Delphinus, Christopher Mclellan

Chris McLellan

Purpose: The aim of this study was to compare asynchronous (ASY) arm cranking (cranks at 180° relative to each other) with synchronous (SYN) arm cranking (parallel crank setting) during the 30 s Wingate anaerobic test.

Methods: Thirty-two physically active men (aged 22.1 ± 2.4 y) completed two Wingate tests (one ASY and one SYN) separated by 4 d in a randomized counterbalanced order. The Wingate tests were completed on a modified electromagnetically braked cycle ergometer. Performance measures assessed during the two tests include peak power, mean power, minimum power, time to peak power, rate to fatigue and maximum …

Form And Function Of Clostridium Thermocellum Biofilms, Alexandru Dumitrache, Gideon Wolfaardt, Grant Allen, Steven N. Liss, Lee R. Lynd

Dartmouth Scholarship

The importance of bacterial adherence has been acknowledged in microbial lignocellulose conversion studies; however, few reports have described the function and structure of biofilms supported by cellulosic substrates. We investigated the organization, dynamic formation, and carbon flow associated with biofilms of the obligately anaerobic cellulolytic bacterium Clostridium thermocellum 27405. Using noninvasive, in situ fluorescence imaging, we showed biofilms capable of near complete substrate conversion with a characteristic monolayered cell structure without an extracellular polymeric matrix typically seen in biofilms. Cell division at the interface and terminal endospores appeared throughout all stages of biofilm growth. Using continuous-flow reactors with a rate …

Murine Gammaherpesvirus 68 Lana Acts On Terminal Repeat Dna To Mediate Episome Persistence, Aline C. Habison, Chantal Beauchemin, J. Pedro Simas, Edward J. Usherwood

Dartmouth Scholarship

Murine gammaherpesvirus 68 (MHV68) ORF73 (mLANA) has sequence homology to Kaposi’s sarcoma-associated herpesvirus (KSHV) latency-associated nuclear antigen (LANA). LANA acts on the KSHV terminal repeat (TR) elements to mediate KSHV episome maintenance. Disruption of mLANA expression severely reduces the ability of MHV68 to establish latent infection in mice, consistent with the possibility that mLANA mediates episome persistence. Here we assess the roles of mLANA and MHV68 TR (mTR) elements in episome persistence. mTR-associated DNA persisted as an episome in latently MHV68-infected tumor cells, demonstrating that the mTR elements can serve as a cis-acting element for MHV68 episome maintenance. In some …

Minor Pilins Of The Type Iv Pilus System Participate In The Negative Regulation Of Swarming Motility, S L. Kuchma, E. F. Griffin, G. A. O'Toole

Dartmouth Scholarship

Pseudomonas aeruginosa exhibits distinct surface-associated behaviors, including biofilm formation, flagellum-mediated swarming motility, and type IV pilus-driven twitching. Here, we report a role for the minor pilins, PilW and PilX, components of the type IV pilus assembly machinery, in the repression of swarming motility. Mutating either the pilW or pilX gene alleviates the inhibition of swarming motility observed for strains with elevated levels of the intracellular signaling molecule cyclic di-GMP (c-di-GMP) due to loss of BifA, a c-di-GMP-degrading phosphodiesterase. Blocking PilD peptidase-mediated processing of PilW and PilX renders the unprocessed proteins defective for pilus assembly but still functional in c-di-GMP-mediated swarming …

Modulation Of Cardiac Pacemaker Channels By Tyrosine Phosphorylation, Jianying Huang

Graduate Theses, Dissertations, and Problem Reports

Encoded by hyperpolarization-activated cyclic nucleotide-gated (HCN) channels, the cardiac pacemaker current If is a major determinant of diastolic depolarization in sinus node myocytes and has a key role in the origin of heart beat. My dissertation consists of two chapters, focusing on the modulation of If and HCN channels by tyrosine phosphorylation, which is maintained by a fine balance between tyrosine kinases and phosphatases. Chapter 1 aims to investigate the role of Src tyrosine kinases in the regulation of sinus node If and HCN channels; Chapter 2 explores the modulation of ventricular If and HCN channels by a family of …

C-Peptide Improves Hyperglycemia-Induced Endothelial Redox Balance By Preventing Mitochondrial Oxidative Stress And Enhancing Nadph Synthesis, Himani Vejandla

Graduate Theses, Dissertations, and Problem Reports

C-peptide, a by-product of insulin biosynthesis, has been shown to ameliorate diabetes-induced renal impairment. Yet, the mechanisms underlying this protective benefit remain unclear. Our studies have shown that C-peptide improved renal peritubular capillary blood flow and reduced vascular oxidants. NADPH (reduced nicotinamide adenine dinucleotide phosphate), appears to be critical to this effect via the actions of numerous vasoprotective systems. Further, our experiments in type I diabetic mice resulted in a significant reduction in renal endothelial NADPH that is subsequently restored with C-peptide. We hypothesized that C-peptide provides protection to renal cortical endothelial cells during type I diabetes by restoring the …

Genetic Basis For Thermal Tolerance In Two Different Strains Of Rainbow Trout (Oncorhynchus Mykiss): Case Western And Kamloops, Paola Reale

Graduate Theses, Dissertations, and Problem Reports

This thesis examines the thermal tolerance based on how expression of Heat Shock Protein (HSP) 70 and HSP90 differ between two different strains of rainbow trout (Oncorhynchus mykiss), the Case Western strain and the Kamloops strain, and determines if cortisol levels affect HSP expression in red blood cells. The Case Western strain is considered the only warm water trout, only recently was any aspect of its thermal tolerance quantified. Porto (2012) determined critical thermal maxima (CTM) for the Case Western strain and found it to be about 0.15 °C higher than the Kamloops strain. This thesis is comprised of three …

Physiological And Genetic Changes In Poplar During Mycorrhizal Colonization Under Phosphorus Limitation, Shalaka Desai

Graduate Theses, Dissertations, and Problem Reports

Poplar species and hybrids are intensively cultivated as renewable sources of biomass because of their rapid growth, extensive genetic variation and ease of propagation. However, the physiological mechanisms underlying soil stress resistance within these poplar species and hybrids are not yet understood. With the recent sequencing of the poplar genome, the use of this species in physiological stress resistance studies may help elucidate the underlying basis of stress resistance in a woody species. Further, although symbiotic mycorrhizal associations have farreaching ecological significance in forest ecosystems, our understanding of the influences of the association on the genetic basis of environmental stress …

Epoxide-Mediated Cifr Repression Of Cif Gene Expression Utilizes Two Binding Sites In Pseudomonas Aeruginosa, Alicia E. Ballok, Christopher D. Bahl, Emily L. Dolben, Allia K. Lindsay, Jessica D. St. Laurent, Deborah Hogan, Dean Madden, George A. O'Toole

Dartmouth Scholarship

Pseudomonas aeruginosa secretes an epoxide hydrolase virulence factor that reduces the apical membrane expression of ABC transporters such as the cystic fibrosis transmembrane conductance regulator (CFTR). This virulence factor, named CFTR inhibitory factor (Cif), is regulated by a TetR-family, epoxide-responsive repressor known as CifR via direct binding and repression. We identified two sites of CifR binding in the intergenic space between cifR and morB, the first gene in the operon containing the cif gene. We have mapped these binding sites and found they are 27 bp in length, and they overlap the -10 and +1 sites of both the cifR …

Rapid Inversion: Running Animals And Robots Swing Like A Pendulum Under Ledges, Jean-Michel Mongeau, Brian Mcrae, Ardian Jusufi, Paul Birkmeyer, Aaron M. Hoover, Ronald Fearing, Robert J. Full

Aaron M. Hoover

Escaping from predators often demands that animals rapidly negotiate complex environments. The smallest animals attain relatively fast speeds with high frequency leg cycling, wing flapping or body undulations, but absolute speeds are slow compared to larger animals. Instead, small animals benefit from the advantages of enhanced maneuverability in part due to scaling. Here, we report a novel behavior in small, legged runners that may facilitate their escape by disappearance from predators. We video recorded cockroaches and geckos rapidly running up an incline toward a ledge, digitized their motion and created a simple model to generalize the behavior. Both species ran …

Multivoxel Patterns In Face-Sensitive Temporal Regions Reveal An Encoding Schema Based On Detecting Life In A Face, Christine E. Looser, Jyothi S. Guntupalli, Thalia Wheatley

Dartmouth Scholarship

More than a decade of research has demonstrated that faces evoke prioritized processing in a ‘core face network’ of three brain regions. However, whether these regions prioritize the detection of global facial form (shared by humans and mannequins) or the detection of life in a face has remained unclear. Here, we dissociate form-based and animacy-based encoding of faces by using animate and inanimate faces with human form (humans, mannequins) and dog form (real dogs, toy dogs). We used multivariate pattern analysis of BOLD responses to uncover the representational similarity space for each area in the core face network. Here, we …

Testing Crayfish Evolutionary Hypotheses With Phylogenetic Methods, Jesse W. Breinholt

Theses and Dissertations

This dissertation focuses on increasing the understanding of the evolution processes that have contributed to the diversification of freshwater crayfish. Chapter one estimates the divergence time of the three crayfish families and tests the hypothesis that diversification is tied to the break-up of Pangaea, Gondwanna, and Laurasia. I find that the families of crayfish diverged prior to or in association with the break-up of the three super continents. Chapter two addresses the evolutionary history of the genus Cambarus, using molecular data to test hypotheses of relationships based on chela and carapace morphology. The results provide evidence that the morphology used …

Imaging Prior Information In The Brain, Scott Gorlin, Ming Meng, Jitendra Sharma, Hiroki Sugihara

Dartmouth Scholarship

In making sense of the visual world, the brain's processing is driven by two factors: the physical information provided by the eyes (“bottom-up” data) and the expectancies driven by past experience (“top-down” influences). We use degraded stimuli to tease apart the effects of bottom-up and top-down processes because they are easier to recognize with prior knowledge of undegraded images. Using machine learning algorithms, we quantify the amount of information that brain regions contain about stimuli as the subject learns the coherent images. Our results show that several distinct regions, including high-level visual areas and the retinotopic cortex, contain more information …

The Conundrum Of Functional Brain Networks: Small-World Efficiency Or Fractal Modularity, Lazaros K. Gallos, Mariano Sigman, Hernán A. Makse

Publications and Research

The human brain has been studied at multiple scales, from neurons, circuits, areas with well-defined anatomical and functional boundaries, to large-scale functional networks which mediate coherent cognition. In a recent work, we addressed the problem of the hierarchical organization in the brain through network analysis. Our analysis identified functional brain modules of fractal structure that were inter-connected in a small-world topology. Here, we provide more details on the use of network science tools to elaborate on this behavior. We indicate the importance of using percolation theory to highlight the modular character of the functional brain network. These modules present a …

Corneal Replication Is An Interferon Response-Independent Bottleneck For Virulence Of Herpes Simplex Virus 1 In The Absence Of Virion Host Shutoff, Tracy J. Pasieka, Vineet D. Menachery, Pamela C. Rosato, David A. Leib

Dartmouth Scholarship

Herpes simplex viruses lacking the virion host shutoff function (Δvhs) are avirulent and hypersensitive to type I and type II interferon (IFN). In this study, we demonstrate that even in the absence of IFN responses in AG129 (IFN-αβγR^−/−) mice, Δvhs remains highly attenuated via corneal infection but is fully virulent via intracranial infection. The data demonstrate that the interferon-independent inherent replication defect of Δvhs has a significant impact upon peripheral replication and neuroinvasion.

The Effects Of Aerobic Exercise Training On Arterial Stiffness In The Metabolic Syndrome, Brian Lee Reger

Graduate Theses, Dissertations, and Problem Reports

Background: Arterial dysfunction, due in part to arterial stiffening, is recognized as a surrogate end point for cardiovascular disease (CVD) and predicts the risk of future CV events. The metabolic syndrome (MetS) is a clustering of risk factors associated with increased stiffening and carotid artery thickening. Aerobic exercise is a well-established therapy that reduces CV events, and has proven to be an effective intervention against arterial stiffening and pathological wall remodeling in the healthy, hypertensive, and diabetic population.;Aims: The purpose of this thesis was to examine the impact of aerobic exercise training on arterial stiffness and wall remodeling in MetS …

Bisphenol A Alters The Function And Expression Of Bk Channels In Vascular Smooth Muscle Through Membrane And Nuclear Signals, Shinichi Asano

Graduate Theses, Dissertations, and Problem Reports

Bisphenol A (BPA) exposure has recently become a public health concern, and the safety of the utilization of BPA has attracted the attention of the scientific community, politicians, and the general population. Although BPA is banned from baby products in a few countries because infants and young children are particularly susceptible to endocrine disruption, recent studies have consistently indicated the association between urinary BPA concentration and cardiovascular diseases in adults. Therefore, adult exposure to this xenoestrogen is becoming a healthcare issue that cannot be ignored. We selected large conductance Ca2+/voltage sensitive potassium (BK) channels as one of the target proteins …

The Nation Before Taste: The Challenges Of American Culinary History, Andrew P. Haley

Faculty Publications

Food is material and familiar, and because it is, we are often overconfident about our ability to understand the culinary past. It is easy to believe that if we can discover the recipe for some forgotten dish, the history of the dish becomes intelligible. When it does not, it tempts those who consume culinary history to impose modern sensibilities on our predecessors. The Nation before Taste" argues that historians and museum curators must be especially vigilant when presenting the history of food. Reviewing a series of historical challenges that stemmed from studying the United States in the late nineteenth and …

Effects Of Environmental Enrichment Strategies On Behavior And Production Performance Of Broiler Breeder Chickens Reared At Elevated Temperatures, Oluwatoyin Bukunmi Adeniji

Masters Theses

Enriched housing systems are embraced as better alternatives to bare housing systems for table egg laying hens. However, attention is presently turning to the meat type (broiler breeder) laying hens. Hence, this experiment investigated the effects of perch structures and sharp sand on behavior, physiology, and production performance of broiler breeder chickens reared under elevated temperatures.

Two hundred and eighty eight broiler breeder females and 48 males (Cobb 500) at 21-weeks-old were assigned to their respective treatments in two different rooms. One room was maintained at 23°C to mimic a thermoneutral environment while the second room cycled between 23°C and …

Mitogen Activated Protein Kinase Phosphatase-1 Prevents The Development Of Tactile Sensitivity In A Rodent Model Of Neuropathic Pain, Christian Ndong, Russell P. Landry, Joyce A. Deleo, Edgar A. Romero-Sandoval

Dartmouth Scholarship

Neuropathic pain due to nerve injury is one of the most difficult types of pain to treat. Following peripheral nerve injury, neuronal and glial plastic changes contribute to central sensitization and perpetuation of mechanical hypersensitivity in rodents. The mitogen activated protein kinase (MAPK) family is pivotal in this spinal cord plasticity. MAPK phosphatases (MKPs) limit inflammatory processes by dephosphorylating MAPKs. For example, MKP-1 preferentially dephosphorylates p-p38. Since spinal p-p38 is pivotal for the development of chronic hypersensitivity in rodent models of pain, and p-p38 inhibitors have shown clinical potential in acute and chronic pain patients, we hypothesize that induction of …

Predicting Ecosystem Shifts Requires New Approaches That Integrate The Effects Of Climate Change Across Entire Systems., Bayden D. Russell, Christopher D.G. Harley, Thomas Wernberg, Nova Mieszkowska, Stephen Widdicombe, Jason M. Hall-Spencer, Sean D. Connell

School of Biological and Marine Sciences

Most studies that forecast the ecological consequences of climate change target a single species and a single life stage. Depending on climatic impacts on other life stages and on interacting species, however, the results from simple experiments may not translate into accurate predictions of future ecological change. Research needs to move beyond simple experimental studies and environmental envelope projections for single species towards identifying where ecosystem change is likely to occur and the drivers for this change. For this to happen, we advocate research directions that (i) identify the critical species within the target ecosystem, and the life stage(s) most …

Skin Morphology And Humoral Non-Specific Defense Parameters Of Mucus And Plasma In Rainbow Trout, Coho And Atlantic Salmon, M. Fast, N. Ross, Ahmed Mustafa, D. Sims, J. Burka

Ahmed Mustafa Dr.

No abstract provided.

A Fap46 Mutant Provides New Insights Into The Function And Assembly Of The C1d Complex Of The Ciliary Central Apparatus, Jason M. Brown, Christen G. Dipetrillo, Elizabeth F. Smith, George B. Witman

Dartmouth Scholarship

Virtually all motile eukaryotic cilia and flagella have a '9+2' axoneme in which nine doublet microtubules surround two singlet microtubules. Associated with the central pair of microtubules are protein complexes that form at least seven biochemically and structurally distinct central pair projections. Analysis of mutants lacking specific projections has indicated that each may play a unique role in the control of flagellar motility. One of these is the C1d projection previously shown to contain the proteins FAP54, FAP46, FAP74 and FAP221/Pcdp1, which exhibits Ca(2+)-sensitive calmodulin binding. Here we report the isolation and characterization of a Chlamydomonas reinhardtii null mutant for …