Nigerian Psychoactive Alcoholic Herbal Mixture Impacts Behavioural Performance and Caused Brain Biochemical and Histopathological Alterations in Mice

Psychoactive alcoholic herbal mixture is popularly consumed because of the belief on its stimulant and curative effects. This study investigated the neurobehavioral, biochemical and histopathological consequences following its single and repeated co-administration with ethanol to mice. Mice were assessed for sensorimotor, anxiety and memory functions following acute and repeated administration of alcohol herbal mixture (AHM). Alterations in brain acetylcholineterase, nitrite, reduced glutathione (GSH) and malondialdehyde levels were assessed in striatum, prefrontal cortex (PFC) and hippocampus. Neuronal cells counts were determined in the prefrontal cortex and hippocampal tissues. In the acute study, AHM significantly impaired locomotor activity and motor coordination in mice. Repeated administration of AHM and AHM combined with ethanol caused significant impairment of locomotor and motor coordination, increased anxiety-like behavior and impaired memory in mice. Acetylcholinesterase activity was significantly increased in the PFC while nitrite level was elevated in the striatum and PFC. There was significant elevation of malondialdehyde and depletion of GSH in all brain regions as well as reduced neuronal cell counts in the PFC and hippocampus. This study showed evidences of behavioral perturbation and brain biochemical changes in mice, hence repeated consumption of alcoholic herbal mixture might produce substance-attributable harm and quicken neurodegenerative diseases in humans

A Review of Thermal Conductivity Models for Nanofluids

Nanofluids, as new heat transfer fluids, are at the center of attention of researchers, while their measured thermal conductivities are more than for conventional heat transfer fluids. Unfortunately, conventional theoretical and empirical models cannot explain the enhancement of the thermal conductivity of nanofluids. Therefore, it is important to understand the fundamental mechanisms as well as the important parameters that influence the heat transfer in nanofluids. Nanofluids’ thermal conductivity enhancement consists of four major mechanisms: Brownian motion of the nanoparticle, nanolayer, clustering, and the nature of heat transport in the nanoparticles. Important factors that affect the thermal conductivity modeling of nanofluids are particle volume fraction, temperature, particles size, pH, and the size and property of nanolayer. In this paper, each mechanism is explained and proposed models are critically reviewed. It is concluded that there is a lack of a reliable hybrid model that includes all mechanisms and influenced parameters for thermal conductivity of nanofluids. Furthermore, more work needs to be conducted on the nature of heat transfer in nanofluids. A reliable database and experimental data are also needed on the properties of nanoparticles.http://www.tandfonline.com/loi/uhte202016-09-30hb201