The synergy of perceptual psychology, technology, and neuroscience can be used to comprehend how virtual reality affects cognition of human brain. Numerous studies have used neuroimaging modalities to assess the cognitive state and response of the brain with various external stimulations. The virtual reality-based devices are well known to incur visual, auditory, and haptic induced perceptions. Neurophysiological recordings together with virtual stimulations can assist in correlating humans’ physiological perception with response in the environment designed virtually. The effective combination of these two has been utilized to study human behavior, spatial navigation performance, and spatial presence, to name a few. Moreover, virtual reality-based devices can be evaluated for the neurophysiological correlates of cognition through neurophysiological recordings. Challenges exist in the integration of real-time neuronal signals with virtual reality-based devices, and enhancing the experience together with real-time feedback and control through neuronal signals. This article provides an overview of neurophysiological correlates of cognition as revealed by virtual reality experience, together with a description of perception and virtual reality-based neuromodulation, various applications, and existing challenges in this field of research.

The electronic package interconnects electronic signals from one area to another and package delamination is a serious problem in the configuration of materials. This study focused on decreasing the delamination of the low-profile fine pitch ball grid array (LFBGA) and plastic ball grid array (PBGA) packages in terms of polymer thermal issue, metal bonding and bonding mechanisms. PBGA and LFBGA are a very common type of packaging processes in the electronics industry. The present study dealt first with delamination of the LFBGA packaging, through characterization and determination of physical and chemical properties such as surface roughness, surface energy, and contact angle. The relationship between surface roughness and delamination was verified through various roughness bonding experiments. In addition, the surface energy was determined by measuring the contact angle after cleaning the metal surface of Cu, Ni and Cr with Ar + O₂ gas, and, this gas plasma treatment was applied to enhance the adhesive properties. The compositions of the surface were analyzed through an X-ray photoelectron spectroscopy (XPS). Also, the delamination issue between the corner of the heat sink cap and the epoxy resin was observed for delamination of the LFBGA packaging. Further, this study analyzed the PBGA packaging process through the finite element analysis simulation software ANSYS. To improve the heat sink cap delamination issue of the PBGA, a new chamfer design of the corner seat was streamlined to decrease the stress value and delamination. Besides, the simulation results demonstrated that the stress value reduced after increasing the shoulder length. The results implicate that the stress value is inversely proportional to the shoulder width and the chamfer radius. This study demonstrated that the optimization in design was able reduce the delamination phenomena in configuration material.

Researchers have promoted the use of polymer microspheres in medical engineering and biotechnology, such as embedded drug delivery with polylactic acid microspheres. Polycaprolactone (PCL) is a kind of semi-crystalline polymer, which can be utilized in many varieties of organic solvent. Therefore, PCL has been used as a controlled-release drug carrier for long-term treatment. This study focuses on the fabrication process of biodegradable PCL microcarriers with uniform and controllable particle size (size range is ∼5–100 μm) via an emulsion-solvent evaporation process with ultrasonic micro-droplet atomization technology. Through ultrasonic atomization, micro-droplets of PCL solution were sprayed out directly with highly uniform particle size. The oil micro-droplets of PCL were collected with an aqueous stream in an emulsion process to form a water–oil–water emulsion. The ultrasonic atomizer assisting the emulsification process was adjusted via the stirring equipment to enhance the particle size uniformity. As a result, PCL micro-droplets were sprayed into aqueous solution due to the vertical flow field made by the stirring equipment. The yield rates of PCL microcarriers were improved effectively. Moreover, the cancer pharmaceutical doxorubicin (DOX) was added into the process to obtain drug-loaded microcarriers. The drug-loading efficiency in this process was ∼42.2%, and the encapsulation efficiency of the microcarriers was ∼3.21%. Further, we performed docking and MD simulations of the polycaprolactone–doxorubicin hydrochloride interaction that showed their binding affinity and later validated potential inhibitors. Additionally, we have successfully established the dynamic behavior of an entire biochemical pathway in the presence of polycaprolactone with doxorubicin hydrochloride, using a systems biology approach.

Correction for ‘PCL–DOX microdroplets: an evaluation of the enhanced intracellular delivery of doxorubicin in metastatic cancer cells via in silico and in vitro approaches’ by Aman Chandra Kaushik et al., New J. Chem., 2019, DOI: 10.1039/c9nj01902b.