Phenotypic traits such as ornaments and armaments are generally shaped by sexual selection, which often favours larger and more elaborate males compared to females. But can sexual selection also influence the brain? Previous studies in vertebrates report contradictory results with no consistent pattern between variation in brain structure and the strength of sexual selection. We hypothesize that sexual selection will act in a consistent way on two vertebrate brain regions that directly regulate sexual behaviour: the medial preoptic nucleus (MPON) and the ventromedial hypothalamic nucleus (VMN). The MPON regulates male reproductive behaviour whereas the VMN regulates female reproductive behaviour and is also involved in male aggression. To test our hypothesis, we used high‐resolution magnetic resonance imaging combined with traditional histology of brains in 14 dragon lizard species of the genus Ctenophorus that vary in the strength of precopulatory sexual selection. Males belonging to species that experience greater sexual selection had a larger MPON and a smaller VMN. Conversely, females did not show any patterns of variation in these brain regions. As the volumes of both these regions also correlated with brain volume (BV) in our models, we tested whether they show the same pattern of evolution in response to changes in BV and found that the do. Therefore, we show that the primary brain nuclei underlying reproductive behaviour in vertebrates can evolve in a mosaic fashion, differently between males and females, likely in response to sexual selection, and that these same regions are simultaneously evolving in concert in relation to overall brain size.

In this work, hydrophobic of modified SiO2 coating for self cleaning material were prepared by dip-coating methods and solvothermal manual. SiO2 was successfully prepared from silica sand by purified followed sol-gel methods. Tetraetoxysilane (TEOS) and Hexamethyldisilanze (HMDS) were used as surface chemical modification agents with varied mass of SiO2, which were 1, 2, 3, and 4 g. X-ray fluorescence spectrometer (XRF) , X-ray powder diffraction (XRD), Particle size analyzer (PSA), Ultraviolet–visible spectrophotometer (UV-Vis), and Water contact angle (WCA) were employed to investigate the element composition, crystal structure, size of particles, transparency, and hydrophobicity of coating. The results indicated that modified SiO2 coatings has hydrophobic feature as self cleaning material (WCA > 90˚) for indium tin oxide (ITO) glass.

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Agar hydrogel is used for tissue mimicking phantom in magnetic resonance imaging studies. The spin-lattice relaxation time, T1 as an important parameter in Magnetic Resonance Imaging measurement was observed. The T1-value represents how fast the net spin magnetization vector recovers to its equilibrium after generation of magnetic field. To explore mechanical properties of agar, shear modulus was examined using a dynamic mechanical analyser. The relation between mechanical properties and spin-lattice relaxation time of agar hydrogel is discussed.