This paper revises the response of freshwater ostracods to different environmental conditions and anthropogenic impacts, with a worldwide overview of the potential use of these microcrustaceans as bioindicators and several examples of applications in different scenarios. The development of either a single species or an ostracod assemblage is influenced by physical-chemical properties of waters (salinity, temperature, pH, dissolved oxygen), hydraulic conditions, bottom grain sizes or sedimentation rates. In addition to population and community changes, morphological and geochemical changes can also be detected in the ostracod carapace, which serves as a tracer of the water quality. All these features permit to delimit the spatial effects of urban sewages, mining effluents, agricultural wastes, watershed deforestation or road building. These data are the basis for the palaeoenvironmental reconstruction of cores, with an interesting application to archaeology. In addition, favourable results of recently developed bioassays, coupled with an important variability of local assemblages under changing conditions in both waters and sediments, suggest that these microcrustaceans may included between the most promising sentinels groups in freshwater areas. These microcrustaceans show high sensitivity to pesticides, herbicides, heavy metal pollution and oil inputs.

Roots are highly plastic and can acclimate to heterogeneous and stressful conditions. However, there is little knowledge of the effect of moisture gradients on the mechanisms controlling root growth orientation and branching, and how this mechanism may help plants to avoid drought responses. The aim of this study was to isolate mutants of Arabidopsis thaliana with altered hydrotropic responses. Here, altered hydrotropic response 1 ( ahr1 ), a semi-dominant allele segregating as a single gene mutation, was characterized. ahr1 directed the growth of its primary root towards the source of higher water availability and developed an extensive root system over time. This phenotype was intensified in the presence of abscisic acid and was not observed if ahr1 seedlings were grown in a water stress medium without a water potential gradient. In normal growth conditions, primary root growth and root branching of ahr1 were indistinguishable from those of the wild type (wt). The altered hydrotropic growth of ahr1 roots was confirmed when the water-rich source was placed at an angle of 45° from the gravity vector. In this system, roots of ahr1 seedlings grew downward and did not display hydrotropism; however, in the presence of cytokinins, they exhibited hydrotropism like those of the wt, indicating that cytokinins play a critical role in root hydrotropism. The ahr1 mutant represents a valuable genetic resource for the study of the effects of cytokinins in the differential growth of hydrotropism and control of lateral root formation during the hydrotropic response.

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Summary Microgrids (MGs) are widely increasing to manage unequal electrical load requirements based on the infrastructure. The goal of this article is to manage energy in a centralized controller multimicrogrid (MMG) system operated at islanded mode. Renewable energy fluctuations in MG due to weather conditions build oscillation in MG operation modes. To solve this, a three‐stage energy management MMG system is proposed. The proposed system is composed of operating mode prediction by measuring the weather conditions. In islanded mode, energy management is incorporated using a two‐round fuzzy‐based speed (TRFS) algorithm followed by evolutionary game theory and status updating by Markov chain. The TRFS algorithm takes into account voltage, frequency, power factor, total harmonic distortion, and loss of produced power probability parameters. The parallel processing of the TRFS algorithm reduces processing time, then a Stackelberg game with a quasi‐oppositional symbiotic organisms search approach is carried out for power exchange. Markov chain based future prediction of MG states ensures detection of MG operating mode along with weather changes. Simulations are developed in MATLAB Simulink, and their outcomes show better performance than previous work whose results are evaluated in terms of load and generator output at two modes, power generated at individual MG and exchanged power.

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