The synthesis and characterization of MgO-ZrO₂ heterostructures are examined in this work. To promote the creation of nanowires, the Si substrate is first covered with a catalyst layer of various Au thicknesses. Sputtering is used to achieve this deposition. After that, chemical vapor deposition (CVD) with a Au catalyst layer is used to create MgO nanowire arrays on the silicon substrate. Second, MgO/ZrO₂ Core–shell Nanowire Arrays are created by applying ZrO₂ layers to the surface of MgO nanowires of different diameters using chemical vapor deposition (CVD) procedures. The presence of both magnesium oxide (MgO) and zirconium dioxide (ZrO₂) in their oxidized forms was shown by the detailed characterization of the MgO-ZrO₂ core–shell nanowire samples utilizing a variety of methods. Phase formation, mechanical homogeneity, optical characteristics, and topographical structure and roughness were all thoroughly examined at various stresses. MgO hardness values ranged from 1.4 to 3.2 GPa, whereas MgO-ZrO₂ ranged from 0.38 to 1.2 GPa. The I–V parameter study was a further step in the examination of the heterostructure’s electrical properties. The structural, morphological, optical, mechanical, and electrical properties of the MgO-ZrO₂ heterostructure were all thoroughly described using these techniques.

Tinnitus is thought to be caused by damage to the auditory and nonauditory system due to exposure to loud noise, aging, or other etiologies. However, at present, the exact neurophysiological basis of chronic tinnitus remains unknown. To explore whether the function of the limbic system is disturbed in tinnitus, the hippocampus was selected, which plays a vital role in learning and memory. The hippocampal function was examined with a learning and memory procedure. For this purpose, sodium salicylate (NaSal) was used to create a rat animal model of tinnitus, evaluated with prepulse inhibition behavior (PPI). The acquisition and retrieval abilities of spatial memory were measured using the Morris water maze (MWM) in NaSal-treated and control animals, followed by observation of c-Fos and delta-FosB protein expression in the hippocampal field by immunohistochemistry. To further identify the neural substrate for memory change in tinnitus, neurogenesis in the subgranular zone of the dentate gyrus (DG) was compared between the NaSal group and the control group. The results showed that acquisition and retrieval of spatial memory were impaired by NaSal treatment. The expression of c-Fos and delta-FosB protein was also inhibited in NaSal-treated animals. Simultaneously, neurogenesis in the DG was also impaired in tinnitus animals. In general, our data suggest that the hippocampal system (limbic system) may play a key role in tinnitus pathology.

Kisspeptin is one of the fundamental regulators of the neuroendocrine reproductive axis. We hypothesized that the expression of hypothalamic kisspeptin, kisspeptin receptor (KISS1R) and GnRH underlies the seasonal changes of reproduction in Rhesus monkey. We examined the expression of kisspeptin, KISS1R and GnRH (mRNA and protein levels) in the medio-basal hypothalamus (MBH) of adult male rhesus monkeys maintained under free ranging conditions during breeding (BS; January; N = 3) and non-breeding season (NBS, July; n=3). Cerebrospinal fluid (CSF) was collected (four samples collected at 30 min interval/animal from the lumbar vertebrae) for the determination of kisspeptin during BS (November) and NBS (July) along with the determination of peripheral testosterone levels by using specific RIA. A significant increase in the relative mRNA expression of kisspeptin (P < 0.01), KISS1R (P < 0.0005) and GnRH (P < 0.0001) in the MBH was observed during the breeding season. The number of kisspeptin cell bodies significantly increased in the arcuate nucleus (ARC) during the BS (P < 0.0001). The number of GnRH, KISS1R positive, KISS1R positive GnRH cell bodies and contacts between the GnRH and kisspeptin cell bodies were significantly increased (P < 0.01; P < 0.01, P < 0.001 and P < 0.01, respectively) in the BS. The CSF kisspeptin levels (P < 0.0001), peripheral testosterone concentrations (P < 0.0001) and paired testis weight (P < 0.0001) were also increased during the BS monkeys. In conclusion, present study suggested that seasonal changes in the reproductive activity in higher nonhuman-primates are associated with alteration in the hypothalamic kisspeptin system.