https://www.selleckchem.com/products/tp0427736-hcl.html There are unrevealed factors that bring about the performance variations of resistive switching devices. In this work, Pt/CeOx/Pt devices prepared by magnetron sputtering showed rectification in their asymmetrical current-voltage (I-V) curves during voltage sweeps. X-ray photoelectron spectroscopy (XPS) showed that the deposited CeOx film had an inhomogeneous composition, and more oxygen vacancies existed in CeOx near the top electrode. The asymmetrical resistance change of the Pt/CeOx/Pt devices can be explained by the presence of more charged oxygen vacancies in CeOx near the top electrode, along with the Schottky conduction mechanism. This work reveals that the compositional inhomogeneity is inevitable in the magnetron sputtering of oxide targets like CeO2 and can be an important source of device-to-device and cycle-to-cycle variations of memristors.Retinal ganglion cells (RGCs), the retina's output neurons, encode visual information through spiking. The RGC receptive field (RF) represents the basic unit of visual information processing in the retina. RFs are commonly estimated using the spike-triggered average (STA), which is the average of the stimulus patterns to which a given RGC is sensitive. Whereas STA, based on the concept of the average, is simple and intuitive, it leaves more complex structures in the RFs undetected. Alternatively, spike-triggered covariance (STC) analysis provides information on second-order RF statistics. However, STC is computationally cumbersome and difficult to interpret. Thus, the objective of this study was to propose and validate a new computational method, called spike-triggered clustering (STCL), specific for multimodal RFs. Specifically, RFs were fit with a Gaussian mixture model, which provides the means and covariances of multiple RF clusters. The proposed method recovered bipolar stimulus patterns in the RFs of ON-OFF cells, while the STA identified only ON and OFF RG