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Introduction
Published in Guangming Xie, Xingwen Zheng, Bionic Sensing with Artificial Lateral Line Systems for Fish-Like Underwater Robots, 2022
Lateral line system (LLS) is a sensory system which can be found in most species of fish. The major unit of lateral line is neuromast, which is a mechanoreceptive organ enabling fish to respond to mechanical changes in water. It consists of two kinds of neuromasts, namely, superficial neuromasts and canal neuromasts. Superficial neuromasts are situated on the surface of fish skin, while canal neuromasts are enclosed in subepidermal canals [1]. It has been demonstrated that fish can effectively detect flow velocity and pressure in the surrounding flow field using LLS [2]. Based on this characteristic, LLS serves functions in varieties of flow-aided fish behaviors, such as rheotaxis (which specifically refers to turning to face into an oncoming current), obstacle avoidance, schooling, and prey localization [3, 4].
Use of Physiological and Biochemical Measures in Pollution Biology
Published in Alan G. Heath, Water Pollution and Fish Physiology, 2018
Various schemes for detecting body movement have been devised using photocells or movement transducers (discussed in Chapter 12), but there has been only a limited attempt to automate this kind of data gathering (Smith and Bailey, 1988). A different type of bodily activity is the ability to maintain position in a slowly moving current of water (sometimes referred to as rheotaxis). Automated systems have been developed utilizing photocells at the rear of the swimming chamber to detect when the fish loses rheotaxis in response to a toxicant entering the water (Poels, 1977). A 2-year test of a rheotaxis system in The Netherlands successfully detected six alarms produced by increased pollutants in the river and one false alarm (Balk et al., 1994).
Water Ecology
Published in Frank R. Spellman, The Science of Water, 2020
Current in streams is the outstanding feature of streams and the major factor limiting the distribution of organisms. The current is determined by the steepness of the bottom gradient, the roughness of the streambed, and the depth and width of the streambed. The current in streams has promoted many special adaptations by stream organisms. Odum (1971) lists these adaptations as follows (see Figure 6.18): Attachment to a firm substrate: Attachment is to stones, logs, leaves, and other underwater objects such as discarded tires, bottles, pipes, etc. Organisms in this group are primarily composed of the primary producer plants and animals, such as green algae, diatoms, aquatic mosses, caddisfly larvae, and freshwater sponges.The use of hooks and suckers: These organisms have the unusual ability to remain attached and withstand even the strongest rapids. Two Diptera larvae Simulium and Blepharocera are examples.A sticky undersurface: Snails and flatworms are examples of organisms that are able to use their sticky undersurfaces to adhere to underwater surfaces.Flattened and streamlined bodies: All macroconsumers have streamlined bodies, i.e., the body is broad in front and tapers posteriorly to offer minimum resistance to the current. All nektons such as fish, amphibians, and insect larvae exhibit this adaptation. Some organisms have flattened bodies, which enable them to stay under rocks and in narrow places. Examples are water penny, a beetle larva, mayfly, and stonefly nymphs.Positive rheotaxis (rheo: current; taxis: arrangement): An inherent behavioral trait of stream animals (especially those capable of swimming) is to orient themselves upstream and swim against the current.Positive thigmotaxis (thigmo: touch, contact): Another inherent behavior pattern for many stream animals is to cling close to a surface or keep the body in close contact with the surface. This is the reason that stonefly nymphs (when removed from one environment and placed into another) will attempt to cling to just about anything, including each other.
Hydrodynamic behaviors of self-propelled sperms in confined spaces
Published in Engineering Applications of Computational Fluid Mechanics, 2022
Ao Li, Yu-Xiao Luo, Yuan Liu, Yuan-Qing Xu, Fang-Bao Tian, Yong Wang
In the next, the rheotaxis is discussed. In the fertilization process, it is crucial for a sperm to follow the right way to the egg. This makes the sperm have to perform upward swimming, that is, the phenomenon of rheotaxis. It is a fascinating topic that how the sperm to distinguish the flow direction. Some recent studies indicated that the flow shear near the wall is the primary causation of rheotaxis, and the rheotaxis is essentially a passive phenomenon (Zhang et al., 2016) (Ishimoto, 2017). In this paper, we focus on the rheotaxis of the sperm population.
Hydrodynamic study of sperm swimming near a wall based on the immersed boundary-lattice Boltzmann method
Published in Engineering Applications of Computational Fluid Mechanics, 2020
Qiong-Yao Liu, Xiao-Ying Tang, Duan-Duan Chen, Yuan-Qing Xu, Fang-Bao Tian
The third is the mechanism study on the navigation of human sperm. People found that the capacitated sperm was able to perform a targeted migration; this is called sperm navigation. Up to now, three typical sperm navigation patterns had been reported for human sperms. They are the chemotaxis, the thermotaxis, and the rheotaxis. The chemotaxis is that the sperm tends to migrate along the gradient direction of chemokine concentration(Bohmer et al., 2005). The recent research of chemotaxis focused mainly on the pathway of chemical signals in the sperm body(Teves et al., 2009) and the biochemical reaction mechanism(Lishko et al., 2011). The research indicated that continuous rising of the progesterone concentration could activate the Ca2+ pathway inside the sperm tail, and then resulted in an exciting movement to the egg. The thermotaxis is that the sperm tends to migrate from a low-temperature region to a high-temperature region. By studying the temperature difference between the two ends of the rabbit oviduct before and at ovulation, people found that the temperature difference at ovulation was much larger than that before ovulation. This result implies that a larger temperature difference between the two ends of the oviduct may benefit the sperm migrating to the egg(Bahat et al., 2005). As for human sperm, it was found that the thermotaxis could occur in a wide temperature scope of 29-41°C (Boryshpolets et al., 2015). The rheotaxis is that the sperm can adjust its motion by perceiving the flow direction in the ambient fluid (Bretherton & Lord Rothschild, 1961; Kantsler et al., 2014). People found that the capacitated human sperm tended to swim upstream against the current in the low-speed flow, and tended to accumulate at the wall surface if the flow speed grows up to a large level(Ishimoto & Gaffney, 2015). Moreover, in a finite scope of flow speed, a countercurrent swimming sperm will change its ongoing direction if the flow direction is converted, it is considered as a passive physical process(Omori & Ishikawa, 2016; Zhang et al., 2016). In recent years, the motor mechanism in sperm navigation attracted increasing attention in the field of sperm motility. It is closely related to the male reproductive health, and also involves rich unknown mechanisms of the biochemical signal conditioning, the structural dynamics, and the fluid-structure interaction. Therefore, the movement mechanism in sperm navigation has become a research spot of great significance.