2005 — 2008 |
Thompson, Joseph |
N/AActivity Code Description: No activity code was retrieved: click on the grant title for more information |
Collaborative Research. Ontogenetic Changes in Swimming Squid: An Integrative Examination of Jet Structure and Muscular Mechanics @ Franklin and Marshall College
PROJECT ABSTRACTCollaborative Research. Ontogenetic Changes in Swimming Squid: An Integrative Examination of Jet Structure and Muscular Mechanics
Ian K. Bartol (Old Dominion University), Joseph T. Thompson (Saint Joseph's University), and Paul S. Krueger (Southern Methodist University)
Squids are versatile swimmers, having the ability to hover in one spot, change direction or orientation rapidly with apparent ease, and ascend/descend almost vertically. Although squids have fins and arms that are used to varying degrees for propulsion, stability, and maneuverability, it is the pulsed jet that is the foundation of the locomotive system. Pulsed jets in squids, which differ from the more familiar undulatory locomotion of fishes, aquatic reptiles, and aquatic mammals, are generated by alternately filling an internal mantle cavity with water and ejecting that water by powerful mantle contractions through a maneuverable funnel. Pulsed jetting is used by squids of remarkably different sizes, from hatchlings that are only a few millimeters in length to adults that may grow as large as 18 m. Over this wide size range, the physics of fluids plays an important role in the evolution of various jet features (e.g., characteristic vortices known as vortex rings) that are central to propulsive swimming performance. This collaborative project investigates how fluid mechanical constraints shape swimming strategies and muscular mechanics in squid of different life history stages, with the ultimate goal of assessing how propulsive efficiency changes with size. To accomplish this, jet flows, body movements, and muscle properties will be examined in two species of squids, the brief squid Lolliguncula brevis and the oval squid Sepioteuthis lessoniana. These squids, which vary in total length from < 1 cm as hatchlings to >15 cm as adults, will be trained to swim in a flow tank (i.e., an aquatic "treadmill") containing water seeded with light-reflective particles. As particle-laden water is expelled from the funnel, it will be illuminated with lasers and videotaped so that the jet velocity can be determined using a technique known as digital particle image velocimetry (DPIV). These DPIV data will provide direct measurements of jet features and propulsive efficiency. Multiple video cameras positioned on a motorized rail system will be used to collect high-resolution images of the mantle and funnel as the squids swim, providing valuable data on swimming behavior. Because the contractile properties of the mantle change with size and have direct effects on jet flows, detailed measurements of isolated bundles of mantle muscle also will be made using standard muscle mechanical techniques. The integration of DPIV, swimming footage, and muscle mechanical data promises to broaden our understanding of propulsive efficiency in jet-propelled organisms, especially at low size ranges where little is known about the jet mechanism, and provide insight into the evolution of ontogenetic changes in musculoskeletal support systems. These data are relevant not only for biological investigators but also for engineers and designers of emerging technologies, such as synthetic jets and pulsed-jet micro-vehicles. This project will engage undergraduate and graduate students in interdisciplinary research. It will also facilitate minority student involvement, either through direct participation in experiments or through educational development in local public schools and aquariums.
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0.943 |
2010 — 2014 |
Thompson, Joseph |
N/AActivity Code Description: No activity code was retrieved: click on the grant title for more information |
Rui: Collaborative Research. Non-Uniform Distribution of Muscle Fiber Strain in Squid Mantle Muscle: Implications For Musculoskeletal System Structure, Function, and Evolution. @ Franklin and Marshall College
RUI: COLLABORATIVE RESEARCH. Non-uniform distribution of muscle fiber strain in squid mantle muscle: implications for musculoskeletal system structure, function, and evolution.
Joseph T. Thompson (Franklin & Marshall College) and William M. Kier (University of North Carolina), Co-PIs.
Proposal # IOS-0950827
Abstract
The hollow, cylindrical shape of the bodies and muscular organs of soft-bodied invertebrate animals is well suited to functions in skeletal support, movement and locomotion. This ubiquitous shape, however, may incur a previously unrecognized cost - large non-uniformities in shortening among the muscle cells arranged circumferentially around the body. Such non-uniformities pose serious problems for the muscles, connective tissues, and neural control systems of the muscular organ, and may force muscle cells in some regions of the body wall to operate with reduced mechanical efficiency during locomotion and movement. We have identified a hollow cylindrical muscular organ, the mantle of squids, in which circumferential muscle cells at different locations likely produce different amounts of force, shorten at different velocities, and generate different amounts of mechanical work during a single contraction of the tubular body. We will use morphological, electromyographic, and biomechanical approaches to investigate these potential problems and identify mechanisms in the skeletal support system of the mantle that may mitigate them. The results of our work promise to reveal new general principles of function for skeletal support systems, not just for soft-bodied invertebrates but for all animals with cylindrical muscular organs. Our research will provide opportunities for undergraduate and graduate students from diverse ethnic backgrounds to learn experimental techniques in kinematics, muscle physiology, and microscopy. Furthermore, our student participants will gain experience in the collaborative and integrative nature of science as they work in teams with peers from different institutions to collect and analyze data, and present the results of their work at national and local scientific conferences.
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0.903 |
2011 — 2014 |
Thompson, Joseph |
N/AActivity Code Description: No activity code was retrieved: click on the grant title for more information |
Eager: Collaborative Research: a New Integrated Quantitative Metrics Approach For Identifying Coordinated Gaits in Swimming Animals @ Franklin and Marshall College
Quantitative assessment of animal swimming performance is essential to gaining an understanding the ability of aquatic species to compete in and withstand changes in their environment. A thorough understanding of swimming performance requires quantifying both the motion of the propulsors and the resulting fluid flow. For the myriad aquatic animals that use them, the ability to quantify simultaneously fluid flows produced by their various propulsors is constrained by the current methodological approaches that measure flow in only two dimensions. In this project, the investigators propose a novel 3D approach for studying swimming animals. They will focus on the two separate, but coordinated, propulsive systems of squid (jets and fins) as follows: (1) collect 3D data of the complete fluid flow (wake) generated by swimming squid (both fin and jet wakes simultaneously) and 3D kinematic data of the swimming motion; (2) apply new mathematical tools to quantitatively distinguish between hydrodynamic and kinematic patterns (i.e., gaits) based on their physical features; and (3) evaluate the propulsive performance (i.e., thrust and efficiency) associated with gaits identified in step 2. This quantitative approach will illuminate the selective pressures driving the structure, mechanics, and dynamics of the musculoskeletal system that powers and supports the propulsors. This research holds great promise for developing a universal framework for gait identification in any swimmer or flyer, especially those employing multiple propulsors, and thus may potentially transform current methods for studying locomotion. Beyond the field of biology, this quantitative, 3D approach could provide a valuable framework for engineers of bioinspired propulsion systems, who may be seeking improved propulsive performance in compact designs similar to what nature offers. Finally, the collaborative interdisciplinary nature of this project will allow undergraduate and graduate students with diverse backgrounds in physiology, biomechanics, and engineering to interact and acquire training in cutting edge technologies.
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0.903 |
2016 — 2020 |
Thompson, Joseph |
N/AActivity Code Description: No activity code was retrieved: click on the grant title for more information |
Collaborative Research: Hydrodynamic and Muscular Mechanical Investigation of Maneuverability in Cephalopods Throughout Ontogeny @ Franklin and Marshall College
Squids and cuttlefishes are impressive swimmers, having the ability to hover, change direction rapidly, and even swim forward and backward with ease. The key to their locomotive prowess is coordination among their pulsed jet, flapping fins, and flexible arms, but little is presently known about how these units work together throughout these animals' lives as they encounter different physical environments, change developmentally, and experience dissimilar ecosystems. This project focuses on understanding how the jet, fins, and arms operate in concert to produce the necessary forces for exceptional turning, both in terms of muscle capabilities and hydrodynamics, in squid and cuttlefish of different developmental stages (hatchlings to adults). This work will involve cutting edge 3D flow visualization approaches, high-speed video analysis, and advanced mathematical tools that highlight the essential components of high-performance turns. This project promises to (1) advance our understanding of how highly maneuverable marine animals navigate through their complex habitats and (2) reveal key performance characteristics, structures, and behaviors that can be integrated potentially into the design of mechanical bio-inspired systems, such as autonomous underwater vehicles, to improve their turning/docking capabilities. This project incorporates a number of outreach projects, including demonstrations in local schools, participation in robotics competitions, development of web-based tutorials and summer camps, and presentations at aquariums and museums.
Maneuvering in the aquatic environment is a significant component of routine swimming, with proficient maneuvering being essential for predator avoidance, prey capture, and navigation. Despite its importance, understanding of the biomechanics of maneuvering behaviors is limited. An investigation of maneuvering performance in three morphologically distinct species of cephalopods is proposed here. The investigation explores three broad questions: (1) how are the fins, arms, and funnel-jet complex used in concert to maximize turning performance in adult cephalopods; (2) do the relative importance of turning rate and turning radius change over ontogeny and are fewer turning modes observed in young cephalopods; and (3) do fin, arm, and funnel musculoskeletal mechanics change over ontogeny and are such changes associated with differences in maneuvering? These questions will be addressed by collecting measurements of 3D high-speed kinematics and 2D/3D hydrodynamics of wake flows; performing mathematical analyses to quantitatively identify and categorize turning patterns; and measuring both the dynamic passive and active length-force relationship and maximum shortening velocity of muscle fibers that drive the movements used during turning and jet vectoring. The proposed work will: (1) provide data on how an ecologically important marine animal coordinates its novel dual-mode system (jet and fins) and arms to achieve high turning performance, (2) highlight the essential kinematic and hydrodynamic elements of turns, (3) offer insights into how maneuvering capabilities change over a broad ontogenetic range, and (4) provide novel data on the muscle properties of muscular hydrostatic organs and their role in turning.
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0.903 |
2017 — 2019 |
Badea, Alexandra (co-PI) [⬀] Colton, Carol Anne [⬀] Gottschalk, William Kirby Lutz, Michael William Thompson, Joseph Wilbur Williams, Christina L (co-PI) [⬀] |
R01Activity Code Description: To support a discrete, specified, circumscribed project to be performed by the named investigator(s) in an area representing his or her specific interest and competencies. R56Activity Code Description: To provide limited interim research support based on the merit of a pending R01 application while applicant gathers additional data to revise a new or competing renewal application. This grant will underwrite highly meritorious applications that if given the opportunity to revise their application could meet IC recommended standards and would be missed opportunities if not funded. Interim funded ends when the applicant succeeds in obtaining an R01 or other competing award built on the R56 grant. These awards are not renewable. |
Sex and Apoe Genotype Interact to Alter Immune Regulated Metabolism in Ad
Biological sex and APOE genotype are now well known to impact the susceptibility to Alzheimer's disease (AD). However, although well studied, the underlying mechanisms that facilitate AD pathology in females compared to males or, in individuals expressing an APOE4/4 compared to an APOE3/3 genotype, remain unknown. Our preliminary data clearly indicate that the immune response to disease is one principal point of commonality between male/female differences, APOE genotype and AD. Both estrogen levels and APOE genotype alter ?activation status? of brain microglia, thereby impacting brain inflammation. The presence of estrogen is commonly shown to be anti-inflammatory, acting to maintain acquired immune privilege and restrict pro-inflammatory responses. The presence of the APOE4 gene allele in females superimposes an enhanced response to infectious pathogens through its effects on estrogen receptor activation and through APOE4-mediated changes in regulation of immunity. These interactions between inflammation and biological sex and inflammation and APOE genotype have become extremely important to understand in more detail because of the strong, increasing data demonstrating a direct involvement of inflammation in the onset and progression of AD. In this proposal we will establish mouse models that enable a direct comparison of AD- like pathology between male and female mice that will also carry a human APOE3 or APOE4 gene allele (in place of the mouse APOE gene alleles) and will represent either familial or sporadic AD. Baseline morphological and biochemical/gene data will be collected at specific ages from each mouse strain and will serve as base line comparisons to establish male/female differences, APOE and biological sex-regulated APOE- based differences. The relationship of these base line values with age will be correlated to established AD pathologies. Our preliminary data strongly implicate a evolutionary significant metabolic pathway involving arginine/ornithine utilization that is regulated by immunity and is both biological sex and APOE genotype specific. This pathway will be examined in detail using heavy isotope labeling and LC/MS to trace and define specific pathway differences between models. Finally, the impact of estrogen loss (equivalent to the induction of menopause in human women) on the baseline data and the specific pathway analyses will be used to better understand how age related loss of estrogen impacts AD-like pathology.
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0.928 |