Operating System Influence on VLSI Radiation Resistance

The article presents a comparative analysis of radiation resistance levels of complex-functional VLSI when using an operating system (OS) for software development in comparison with the traditional approach based on a superloop. The applied OSs and objects of the research are presented. The features of the program code for functional control tests when using and not using OS are described. Algorithms of conducting experiments in the studies of absorbed dose affects and dose rate effects are presented. Comparisons were made of radiation resistance levels to total ionizing dose (TID) effects and dose rate effects in the presence and in the absence of OS. The obtained results of studies on TID effects demonstrate that the presence of OS can change the radiation resistance level up to ~30% both up and down compared to the traditional case in the absence of OS. Based on the results of dose rate effects studies, it was concluded that the use of OS can reduce the level of fault-tolerant operation by 43% compared to the case in the absence of OS. The results also show that the type of OS also affects the fault-tolerant operation level. Possible explanations of difference in radiation resistance levels are proposed. Directions for futher research are outlined

MEMORY CHIPS AND UNITS RADIATION TOLERANCE DEPENDENCE ON SUPPLY VOLTAGE DURING IRRADIATION AND TEST

In this work we investigate the influence of various memory chips supply voltage on their sensitivity to the radiation environment. The main physical mechanisms responsible for radiation-induced degradation at nominal, increased, and decreased supply voltage values are discussed. It is demonstrated that, depending on supply voltage value during irradiation and subsequent testing, device's tolerance to data corruption effects in memory circuits, single event latch-up (SEL) and hard errors induced by ionizing radiation can vary significantly. We also give some recommendations to perform radiation tests

Characterization of cerebral blood flow dynamics with multiscale entropy

Based on the laser speckle contrast imaging (LSCI) and the multiscale entropy (MSE), we study in this work the blood flow dynamics at the levels of cerebral veins and the surrounding network of microcerebral vessels. We discuss how the phenylephrine-related acute peripheral hypertension is reflected in the cerebral circulation and show that the observed changes are scale-dependent, and they are significantly more pronounced in microcerebral vessels, while the macrocerebral dynamics does not demonstrate authentic inter-group distinctions. We also consider the permeability of blood–brain barrier (BBB) and study its opening caused by sound exposure. We show that alterations associated with the BBB opening can be revealed by the analysis of blood flow at the level of macrocerebral vessels

Abstracts from the 20th International Symposium on Signal Transduction at the Blood-Brain Barriers

https://deepblue.lib.umich.edu/bitstream/2027.42/138963/1/12987_2017_Article_71.pd

Optical coherent tomography and fluorescent microscopy for the study of meningeal lymphatic systems

The development of novel technologies for the imaging of meningeal lymphatic vessels is one of the amazing trends of biophotonics thanks to discovery of brain lymphatics over several years ago. However, there is the limited technologies exist for the study of lymphatics in vivo because lymphatic vessels are transparent with a low speed flow of lymph. Here we demonstrate the successful application of fluorescent microscopy for the imaging of lymphatic system in the mouse brain in vivo

Photodynamic opening of the blood-brain barrier and pathways of brain clearing

A new application of the photodynamic treatment (PDT) is presented for the opening of blood-brain barrier (BBB) and the brain clearing activation that is associated with it, including the use of gold nanoparticles as emerging photosensitizer carriers in PDT. The obtained results clearly demonstrate 2 pathways for the brain clearing: (1) using PDT-opening of BBB and intravenous injection of FITC-dextran we showed a clearance of this tracer via the meningeal lymphatic system in the subdural space; (2) using optical coherence tomography and intraparenchymal injection of gold nanorods, we observed their clearance through the exit gate of cerebral spinal fluid from the brain into the deep cervical lymph node, where the gold nanorods were accumulated. These data contribute to a better understanding of the cerebrovascular effects of PDT and shed light on mechanisms, underlying brain clearing after PDT-related opening of BBB, including clearance from nanoparticles as drug carriers