Effect of parabolic solar energy collectors for water distillation

This research article briefly summarizes the augmentation of condensate output using concentrators. This study compares a single-slope solar still, a compound conical concentrator (CCC) solar still, and a compound parabolic concentrator–tubular solar still (CPC–TSS). The effect of miniaturization of the absorber (increase in the concentration factor) and some modifications in the solar still assembly show a remarkable increase in output. The measured daily yield rate per square meter of absorber area of the single slope solar still, CCC solar still, and CPC–TSS is 2,100, 18,000, and 6,100 ml, respectively. It was found that the CCC solar still provides the maximum yield

Social Interaction in Zebrafish: Effects of Social Isolation on Behaviour, Neurochemistry, and Stress

Characterization and detailed analysis of social behaviour are necessary to further establish zebrafish as a model for developmental disorders such as Autism Spectrum Disorders and Fetal Alcohol Syndrome Disorder. Social isolation has been used as a tool to study regulation of social behaviour in various species before. The purpose of this thesis was to investigate how social isolation (during development or in adulthood) affects subsequent social and non-social behaviours. I also examined neurotransmitter systems associated with social interaction, namely dopamine and serotonin, and stress hormone cortisol, as isolated fish responded to novelty or to social stimuli. I found that life-long developmental isolation increased locomotor activity, and altered responses to social stimuli and dopaminergic metabolite levels. On the other hand, locomotor activity and social responses of socially raised zebrafish remained unchanged after chronic isolation in adulthood, but a reduction in serotonin metabolite levels was found in response to novelty and social interaction. Behavioural and physiological responses of fish isolated in adulthood were also affected by social stimulus type and prior social hierarchy status. Both developmental and chronic adult isolation reduced anxiety-related behaviour, and cortisol levels indicated that long-term social isolation is not stressful in zebrafish. Findings from zebrafish experiments are discussed in light of isolation literature in other social animals. These analyses help establish translationally relevant zebrafish research as a tool to simplify, explore, and understand behaviour and disorders involving social abnormalities in social vertebrates.Ph.D.2019-01-11 00:00:0

Key HPI axis receptors facilitate light adaptive behavior in larval zebrafish

Abstract The vertebrate stress response (SR) is mediated by the hypothalamic–pituitary–adrenal (HPA) axis and contributes to generating context appropriate physiological and behavioral changes. Although the HPA axis plays vital roles both in stressful and basal conditions, research has focused on the response under stress. To understand broader roles of the HPA axis in a changing environment, we characterized an adaptive behavior of larval zebrafish during ambient illumination changes. Genetic abrogation of glucocorticoid receptor (nr3c1) decreased basal locomotor activity in light and darkness. Some key HPI axis receptors (mc2r [ACTH receptor], nr3c1), but not nr3c2 (mineralocorticoid receptor), were required to adapt to light more efficiently but became dispensable when longer illumination was provided. Such light adaptation was more efficient in dimmer light. Our findings show that the HPI axis contributes to the SR, facilitating the phasic response and maintaining an adapted basal state, and that certain adaptations occur without HPI axis activity