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The ultimate challenge for assisted reproductive technologies (ARTs) is to select the most competent sperm population from a semen sample in an efficient way. In this thesis, we report on an effective sperm sorting microfluidic device that exploits the rheotaxis of sperm and investigates the sperm quality sorted under various flow conditions. Rheotaxis is the ability of a sperm cell to orient itself in the direction of the flow and swim against it. We developed a novel passively driven pumping system that provides a steady flow rate while it requires no external power source. We have also developed another rheotaxis-based microfluidic device that washes out the raw semen sample from any dead or less motile sperm. The device consists of a collection and waste chamber. To evaluate the effect of the shape and height of the collection chamber, we measured the sperm motility and velocity parameters after sorting using varying the shape and height of the collection chamber. We demonstrated that sperm selected with all devices have higher motility, normal morphology, and a fewer degree of DNA fragmentation compared to a control group., 2022, Includes bibliography., Degree granted: Dissertation (Ph.D.)--Florida Atlantic University, 2022., Collection: FAU Electronic Theses and Dissertations Collection

The aim of this thesis is to study the adaption behaviors of self-propelled fish in complex environments. In order to do so, a numerical framework is first developed. In this framework, fish swimming in a viscous incompressible flow is simulated with the immersed boundary--lattice Boltzmann method (IB--LBM). Furthermore, a deep recurrent Q-network (DRQN) is incorporated with the IB--LBM to train the fish model to adapt its motion to optimally achieve a specific task, such as prey capture, rheotaxis and Kármán gaiting. Compared to existing models for fish, this work incorporates the fish position, velocity and acceleration into the state space in the DRQN; and it considers the amplitude and frequency action space as well as the historical effects. This framework makes use of the high computational efficiency of the IB--LBM which is of crucial importance for the effective coupling with learning algorithms. Test cases including point-to-point swimming in quiescent flow and position holding both in a uniform stream and a Kármán vortex street have been conducted to show the effectiveness of the proposed framework. With the proposed method, the effect of vision, superficial neuromast (SN) and canal neuromast (CN) in position holding swimming in a uniform flow are then investigated. It is found that the fish is able to hold position with all those sensory methods. The control with vision is most accurate while the control with CN information is least accurate. In addition, the combination of vision, SN and CN will not improve the control with only vision, but the combination of SN and CN outperforms SN or CN alone. The effect of the undulation frequency on fish's behavior in a Kármán vortex street is finally investigated. Result shows that the swimming is most stable and efficient when the fish is synchronizing its tail-beat frequency with the vortex shedding frequency. Higher undulation frequency will decrease the hydrodynamic efficiency, and lower undulation frequency wi

peer-reviewed, Cation channels of sperm (CatSper) are sperm-specific calcium channels with identified roles in the regulation of sperm function in humans, mice, and horses. We sought to employ a comparative genomics approach to identify conserved CATSPER genes in the bovine genome, and profile their expression in reproductive tissue. We hypothesized that CATSPER proteins expressed in bull testicular tissue mediates sperm hyperactivation and their rheotactic response in the reproductive tract of the cow. Bioinformatic analysis identified all four known CATSPER genes (CATSPER 1-4) in the bovine genome, and profiling by quantitative real-time polymerase chain reaction identified site-specific variation in messenger ribonucleic acid (mRNA) expression for all four genes along the reproductive tract of the bull. Using a novel antibody against CATSPER 1, protein expression was confirmed and localized to the principal piece of bull sperm, in agreement with what has been reported in other species. Subsequent treatment of bull sperm with either the calcium chelator ethylene glycol tetraacetic acid; mibefradil, a specific blocker of CatSper channels in human sperm; or CATSPER1 antibody all significantly inhibited caffeine-induced hyperactivation and the rheotactic response, supporting the concept that the calcium influx occurs via CatSper channels. Taken together, the work here provides novel insights into expression and function of CatSper channels in bull testicular tissue and in the function of ejaculated sperm., peer-reviewed

The lateral line sense organ in fish detects fluid flow around its body, and is used to perform a wide variety of behaviors such as rheotaxis, wall-following, prey detection, and obstacle and predator avoidance. Currently there are no equivalent engineering analogues that can sense fluid flow perturbation to determine location of obstacles and demonstrate closed loop obstacle avoidance. In this dissertation we examine the potential and limitations of this sensor system with respect to obstacle detection, avoidance and rheotaxis. This dissertation presents the development of a novel bioinspired flow-based perception scheme for small and wide-field objects, design and development of a strain sensor system and a robust controller for closed loop demonstration of rheotaxis and small and wide field object detection and avoidance. Potential flow based models are developed for the above mentioned problems of interest. As the modeling technique is approximate, the uncertainties due to modeling and effect of rotation rate are accounted for and used in the synthesis of a robust H$_\infty$ control system. The perturbation signals are spatially decomposed using wide and small-field integration techniques to arrive at information regarding objects in the environment. A high-fidelity, computational fluid dynamic closed-loop simulation is carried out by interfacing control codes with an off-the-shelf software to demonstrate behaviors of rheotaxis, wall-following, tunnel centering and unstructured wide-field obstacle avoidance. A bio-inspired hair array sensor and its corresponding signal conditioning electronics were developed for detecting flow perturbations related to the behaviors of interest. The sensors that were manufactured were strain based and involved the use of micro and macro fabrication approaches. An instrumentation amplifier-based system was developed for signal conditioning. The hair array sensors along with the signal conditioning electronics weighed about 10 gms

A fundamental problem in biology is understanding how and why things group together. Collective behavior is observed on all organismic levels - from cells and slime molds, to swarms of insects, flocks of birds, and schooling fish, and in mammals, including humans. The long-term goal of this research is to understand the functions and mechanisms underlying collective behavior in groups. This dissertation focuses on shoaling (aggregating) fish. Shoaling behaviors in fish confer foraging and anti-predator benefits through social cues from other individuals in the group. However, it is not fully understood what information individuals receive from one another or how this information is propagated throughout a group. It is also not fully understood how the environmental conditions and perturbations affect group behaviors. The specific research objective of this dissertation is to gain a better understanding of how certain social and environmental factors affect group behaviors in fish. I focus on two ecologically relevant decision-making behaviors: (i) rheotaxis, or orientation with respect to a flow, and (ii) startle response, a rapid response to a perceived threat. By integrating behavioral and engineering paradigms, I detail specifics of behavior in giant danio Devario aequipinnatus (McClelland 1893), and numerically analyze mathematical models that may be extended to group behavior for fish in general, and potentially other groups of animals as well. These models that predict behavior data, as well as generate additional, testable hypotheses. One of the primary goals of neuroethology is to study an organism's behavior in the context of evolution and ecology. Here, I focus on studying ecologically relevant behaviors in giant danio in order to better understand collective behavior in fish. The experiments in this dissertation provide contributions to fish ecology, collective behavior, and biologically-inspired robotics.

This study summarizes laboratory swim studies of two species of Asian carp, 36-334 mm total length, and suggests ways that swimming performance data can be used to contain these invasive species. Bighead carp (Hypophthalmichthys nobilis) and silver carp (H. molitrix) are native to China but are now established and spreading throughout North America. Following their introduction in the Lower Mississippi River in the 1980s, both species have dispersed upriver towards the Great Lakes and laterally into floodplain wetlands and tributaries (Kolar et al. 2007). Their diets overlap highly with those of native planktivorous fishes (Sampson et al. 2009). Because they consume large quantities of food representing a wide variety of taxa (Jennings 1988), selectively digesting and egesting viable algae (Pongruktham et al. 2010), they can alter food webs and increase trophic competition (Pegg et al. 2009), reducing the robustness (condition) of native fishes like gizzard shad (Dorosoma cepedianum), bigmouth buffalo (Ictiobus cyprinellus) (Irons et al. 2007), and possibly paddlefish (Polyodon spathula) (Varble et al. 2007). Predicting rates and likelihood of carp dispersal and containing populations with hydraulic barriers (or other types of barriers) are options for managers, but quantitative data are required on swimming performance of carp.

Tagging of Haliotis tuberculata in the natural environment and regular observations during several periods showed that the movements of this species is slight. During one year, 32% of the tagged population did not move and the mean range of movement was 6.7 m for moving individuals. There is a seasonal trend in the movements which appears to be higher in autumn. No relation was found between movements and growth but mobility decreased with the size of individuals. The migration of a population is oriented toward the direction of swell and main currents., Le suivi régulier d'ormeaux marqués, dans le milieu naturel et à différentes échelles de temps, montre qu'Haliotis tuberculata est une espèce peu mobile. Pendant un an, 32 % des individus sont restés stationnaires et l'amplitude moyenne du déplacement des spécimens mobiles a été de 6,7 m. Le taux de déplacement, maximal en automne, suit un cycle saisonnier. 1.1 n'existe pas de relation entre la croissance et la mobilité ; par contre, cette dernière diminue avec l'âge des ormeaux. La migration d'une population est orientée selon la direction d'où proviennent les houles et les principaux courants.

Tagging of Haliotis tuberculata in the natural environment and regular observations during several periods showed that the movements of this species is slight. During one year, 32% of the tagged population did not move and the mean range of movement was 6.7 m for moving individuals. There is a seasonal trend in the movements which appears to be higher in autumn. No relation was found between movements and growth but mobility decreased with the size of individuals. The migration of a population is oriented toward the direction of swell and main currents., Le suivi régulier d'ormeaux marqués, dans le milieu naturel et à différentes échelles de temps, montre qu'Haliotis tuberculata est une espèce peu mobile. Pendant un an, 32 % des individus sont restés stationnaires et l'amplitude moyenne du déplacement des spécimens mobiles a été de 6,7 m. Le taux de déplacement, maximal en automne, suit un cycle saisonnier. 1.1 n'existe pas de relation entre la croissance et la mobilité ; par contre, cette dernière diminue avec l'âge des ormeaux. La migration d'une population est orientée selon la direction d'où proviennent les houles et les principaux courants.

Tagging of Haliotis tuberculata in the natural environment and regular observations during several periods showed that the movements of this species is slight. During one year, 32% of the tagged population did not move and the mean range of movement was 6.7 m for moving individuals. There is a seasonal trend in the movements which appears to be higher in autumn. No relation was found between movements and growth but mobility decreased with the size of individuals. The migration of a population is oriented toward the direction of swell and main currents., Le suivi régulier d'ormeaux marqués, dans le milieu naturel et à différentes échelles de temps, montre qu'Haliotis tuberculata est une espèce peu mobile. Pendant un an, 32 % des individus sont restés stationnaires et l'amplitude moyenne du déplacement des spécimens mobiles a été de 6,7 m. Le taux de déplacement, maximal en automne, suit un cycle saisonnier. 1.1 n'existe pas de relation entre la croissance et la mobilité ; par contre, cette dernière diminue avec l'âge des ormeaux. La migration d'une population est orientée selon la direction d'où proviennent les houles et les principaux courants.

Tagging of Haliotis tuberculata in the natural environment and regular observations during several periods showed that the movements of this species is slight. During one year, 32% of the tagged population did not move and the mean range of movement was 6.7 m for moving individuals. There is a seasonal trend in the movements which appears to be higher in autumn. No relation was found between movements and growth but mobility decreased with the size of individuals. The migration of a population is oriented toward the direction of swell and main currents., Le suivi régulier d'ormeaux marqués, dans le milieu naturel et à différentes échelles de temps, montre qu'Haliotis tuberculata est une espèce peu mobile. Pendant un an, 32 % des individus sont restés stationnaires et l'amplitude moyenne du déplacement des spécimens mobiles a été de 6,7 m. Le taux de déplacement, maximal en automne, suit un cycle saisonnier. 1.1 n'existe pas de relation entre la croissance et la mobilité ; par contre, cette dernière diminue avec l'âge des ormeaux. La migration d'une population est orientée selon la direction d'où proviennent les houles et les principaux courants.