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Pollution
Published in Brian D. Fath, Sven E. Jørgensen, Megan Cole, Managing Global Resources and Universal Processes, 2020
Vera Lucia S.S. de Castro, Paola Poli
Both chronic and acute contamination of watershed by pesticides dissolved or adsorbed to soil particles can affect aquatic organisms. Pesticide toxicity may occur in a broad range of non-target aquatic organisms, both in plants from microalgae to macrophytes and in animals from microinvertebrates to fish predators. The possible effects of pesticide exposure on fish are of interest because of the position of fish in the food chain and because early life stages of fish have been shown to be highly sensitive to pollutants. Genotoxicity assessment in fish has been highlighted since the implications of the genotoxic effects are impacting on fitness traits such as reproductive success, genetic patterns, and subsequent population dynamics.[29]
Introduction to AI-Based Control
Published in Jitendra R. Raol, Ramakalyan Ayyagari, Control Systems, 2020
Jitendra R. Raol, Ramakalyan Ayyagari
Continuing the analogy of natural selection in biological evolution, the fitness function is like the habitat to which organisms adapt. It is the only step in the algorithm that determines how the chromosomes will change over time, and can mean the difference between finding the optimal solution and finding no solutions at all. Kinnear4 explains that the fitness function is the only chance that you have to communicate your intentions to the powerful process that genetic programming represents. Moreover, the fitness function must be more sensitive than just detecting what is a “good” chromosome versus a “bad” chromosome: it needs to accurately score the chromosomes based on a range of fitness values, so that a somewhat complete solution can be distinguished from a more complete solution. It is important to consider which partial solutions should be favored over other partial solutions because that will determine the direction in which the whole population moves.
Evolutionary Computation and Swarm Intelligence
Published in Soumya D. Mohanty, Swarm Intelligence Methods for Statistical Regression, 2018
Biological evolution of species is nothing but an optimization algorithm that moves the genetic makeup of a population of organisms towards higher fitness in their environment. The elementary picture of evolution, which is more than sufficient for our purpose, is that individuals in a species have variations in their genetic code that is brought about by mutation and gene mixing through sexual reproduction. Over multiple generations, the process of natural selection operates on the population to weed out individuals with genetic traits that result in lower fitness. Individuals with higher fitness in any given generation have a better chance at surviving and go on to produce offsprings that share the beneficial genetic trait. This results in the advantageous genetic trait gradually spreading throughout the population.
Increasing cannabis use and importance as an environmental contaminant mixture and associated risks to exposed biota: A review
Published in Critical Reviews in Environmental Science and Technology, 2022
Emily K. C. Kennedy, Genevieve A. Perono, Dion B. Nemez, Alison C. Holloway, Philippe J. Thomas, Robert Letcher, Chris Marvin, Jorg Stetefeld, Jake Stout, Oliver Peters, Vince Palace, Gregg Tomy
Behavioral changes have been observed in Δ9-THC exposed zebrafish during which the ability of the fish to locate food in a maze was impaired following acute exposure to a 100 nM solution of Δ9-THC (Ruhl et al., 2014). Other studies have reported alterations in swimming behaviors in zebrafish exposed to Δ9-THC (30 mg/L and 50 mg/L) which resulted in a shift from top-swimming to slow bottom swimming (Stewart & Kalueff, 2014). Carty et al. (2018) tested the behavioral effects of both Δ9-THC and CBD and found that when exposed to low concentrations of cannabinoids, 0.3 mg/L (Δ9-THC) and 0.07 mg/L (CBD) zebrafish larvae were more active during dark periods when compared to controls but at higher concentrations of 1.25 mg/L (Δ9-THC) and 0.1-0.3 mg/L (CBD) hypolocomotion was observed (Carty et al., 2018). Behaviors strongly related to overall fitness like reproductive effort, feeding and predator/prey relationships, when altered, can have detrimental effects on individuals and eventually the ecosystem as a whole (Brodin et al., 2014; Scott & Sloman, 2004). Because cannabinoids exert their effects by interacting directly with the central nervous system, and because the CNS coordinates behavior, such alterations may be an important factor in cannabinoid toxicity to aquatic organisms. More research and studies are warranted in e.g. other fish species, to address these knowledge gaps.
Optimal Deep Neural Network-Based Model for Answering Visual Medical Question
Published in Cybernetics and Systems, 2022
Karim Gasmi, Ibtihel Ben Ltaifa, Gaël Lejeune, Hamoud Alshammari, Lassaad Ben Ammar, Mahmood A. Mahmood
This is also true of GA, which uses a finite length of string coding for each solution’s parameters in the search problem. Each string represents a person, and the fitness value of each individual increases its power during the course of survival. Evolutionary performance improves with higher fitness values. A generation is made up of a certain number of people. Every generation, parents are chosen based on their fitness values, and strings of children are then generated via a variety of genetic operators. The new generation is created with the help of their computed fitness levels. As long as a certain threshold is reached, the process is repeated. When a population’s average fitness increases over time, it reflects an improvement in overall quality of life.
An improved hybrid self-inertia weight adaptive particle swarm optimization algorithm with local search
Published in Engineering Optimization, 2019
Arfan Ali Nagra, Fei Han, Qing Hua Ling
For the evaluation of extrema tracking, the performance of the proposed inertia weight dynamic tested functions is generated using the moving peaks benchmark (MPB). MPB is a widely used benchmark problem proposed by Branke (1999). The parameters applied to MPB are given in Table 3. The ability of PSO with different inertia weight strategies in extrema tracking is measured through the current error and offline error. The method that is used for detecting environmental changes is to re-evaluate the global best particle before updating the global best particle. A fitness change indicates that an environmental change has occurred.