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Chemical Uptake by Organisms
Published in J. Mark Parnis, Donald Mackay, Multimedia Environmental Models, 2020
Apparently, the chemical passively diffuses into the fish via the gills into the circulating blood and then into other tissues, taking the same route as oxygen. In the laboratory, it is usual to expose a fish to a constant water concentration for a period of time during which the concentration in the fish should rise from zero to CF according to the integrated version of the differential equation with CF initially zero and CW constant: CF=(k1k2)CW[1−exp(−k2t)]
An Experimental Investigation of Aquatic Propulsion using Undulating Fins
Published in P. C. Thomas, Vishal John Mathai, Geevarghese Titus, Emerging Technologies for Sustainability, 2020
Albin Sunny, Allen Issac, Alfred Biju, Jerry Babu, George Sebastian
Most aquatic vertebrates achieve undulatory propulsion [1] by sending alternating waves down the body towards the tip of the tail. These waves cause the body to oscillate sinusoidally and create a jet in the wake and hence a forward force, namely thrust. Undulatory swimming is a highly effective [2] means of continuous locomotion by aquatic vertebrates. This study concerns the robotic emulation of the propulsion mechanism of the weakly electric knifefish from the Amazon Basin, the black ghost (Apteronotus Albifrons). The fish hunts and navigates [3] in geometrically complex environment of Amazon Basin Rivers. The Black Ghost Knife fish propels [4] by sending sinusoidal waves from the head or tail, the direction of wave motion depends on the mode of motion i.e. forward or backward swimming. Undulatory motion helps them to swim smoothly through the turbulent water currents with higher efficiency. While observing Black Ghost Knife fish, counter waves are also seen at the tail portion. For example, during forward swimming, the wave travels from head to tail portion of the fish, which produces a forward reactive force and drives the fish forward. During forward swimming, a low amplitude wave was also seen traveling from tail to head to overcome the disturbances in the water. The fish also generate sinusoidal waves of equal amplitude from the head and the tail portion to hover-staying [5] stationary with active stabilization against perturbations.
Fish School Search Algorithm
Published in A Vasuki, Nature-Inspired Optimization Algorithms, 2020
Fish are vertebrate aquatic animals that can be found in almost all waterbodies, from flowing streams to lakes and deep oceans. More than 30,000 diversified species of fish have been identified, and they are available in plenty in all types of waterbodies. They use underwater acoustics to communicate with members of their own species. Fish are one of the main sources of food for the human race while some varieties are used for ornamental purposes. Fish are supposed to be ‘cold-blooded’ because their body temperature changes with the ambient temperature of water. Fish have a streamlined body for swimming that is covered with scales, with multiple pairs of fins and gills for breathing. The size of fish varies from the tiny fish less than 10 mm in length to the big sharks that are 16 to 20 m in length. Fish have jaws for eating, and they feed on plants and other organisms, and the bigger fish sometimes feed on the smaller fish. Fish reproduce by laying eggs that are either hatched outside or nourished inside.
Acid and enzymatic extraction of collagen from Atlantic cod (Gadus Morhua) swim bladders envisaging health-related applications
Published in Journal of Biomaterials Science, Polymer Edition, 2020
Rita O. Sousa, Ana L. Alves, Duarte Nuno Carvalho, Eva Martins, Catarina Oliveira, Tiago H. Silva, Rui L. Reis
The main part of the fish by-products resulting from the fisheries and food processing industries is still directed for fish silage, fishmeal and oil production, mainly used for animal feed [3,4]. Nevertheless, cod by-products have already been used, for example, for the extraction of collagen [5,6] and fish leather production from skin, the extraction of calcium phosphates such as hydroxyapatite from bones [7], the isolation of enzymes from liver, as well as other valuable compounds from viscera or muscle [4]. In this project, swim bladders were removed from salt-cured cod (Gadus morhua) and used to extract fish protein - collagen. The swim bladder or air bladder is an internal gas-filled organ that contributes to the ability of many bony fish (but not cartilaginous fish) to control their buoyancy, avoiding the waste of energy in swimming. Additionally, the swim bladder functions as a resonating chamber, to produce or receive sound and it is evolutionarily homologous to the lungs [8,9]. The swim bladder consists of three main layers: tunica externa, submucosa, and mucosa. The tunica externa is composed of a dense layer of connective tissue [9], being a potential source for the production of collagen.
Biomarkers as tools to assess the chronic toxicity of ammonia in the juvenile Mugil cephalus
Published in Chemistry and Ecology, 2018
Mei Jiang, Lei Li, Xinqiang Shen
The outcome of chemical exposure is dependent on the capability and efficiency of biotransformation and elimination processes. All the processes need additional energy to support their functioning. Therefore, assessing the activity of enzymes involved in the pathways of cell energy production may provide valuable information [6]. Na+-K+-ATPase exists extensively in aquatic animals and participates in essential biochemical processes, including energy metabolism, material transport, and oxidatve phosphorylation [7]. Na+-K+-ATPase enzyme in the basolateral membrane of branchial cells is closely associated with NH3–N excretion and plays an important role in reducing NH3–N buildup in the haemolymph, thereby minimising toxic effects of NH3 during environmental NH3 exposure [8]. Gills are used by fish to breathe, excrete ammonia, and regulate osmotic pressure. Na+-K+-ATPase is an enzyme present in the membrane of chloride cells and organelles of gills. Na+-K+-ATPase serves an important function in osmotic regulation [9].
Evolvement rule and hydrodynamic effect of fluid field around fish-like model from starting to cruising
Published in Engineering Applications of Computational Fluid Mechanics, 2020
Xue Gang, Liu Yanjun, Si Weiwei, Xue Yifan, Guo Fengxiang, Li Zhitong
A fish can move up and down by adjusting its density through its swim bladder. We also paid attention to the effect of the fluid field with various fish-like model densities. We kept the envelope volume of the fish-like model unchanged, and changed the shell density of the model. Then, the average density of the model would be changed. We defined to represent the relative density of the fish-like model, as: where denotes the shell density of the fish-like model, and denotes the density of fluid around the model.