Selective Segment Initialization: Exploiting NVRAM to Reduce Device Startup Latency

Abstract-We propose Selective Segment Initialization (SSI) to exploit NVRAM to reduce the device startup latency. SSI locates a kernel binary image in byte-addressable NVRAM and boots the system using this image, eliminating the need to load it from storage. SSI also eliminates the process of decompressing and relocating the OS kernel image in embedded linux system. The key technical ingredients of SSI are precisely identifying the kernel segments where contents are updated in the course of booting and selectively reloading only these sections each time the system reboots. The fresh copy of the sections can be maintained in NVRAM, NAND flash, NOR flash, etc. SSI reduced the size of the kernel binary image loaded from storage into memory by 90% and reduced the overall device startup time by 54%. This approach can be used not only for cold boot (with NVRAM) but also for warm boot, in which the contents of DRAM persist across the system restart

Role of TGFbeta2 in cardiac neural crest cells

Neural crest cells (NC) are multi-potent cells which originate in the dorsal neural tube and migrate to the mammalian heart during embryonic development. Defective migration of NC results in defects in the outflow tract region of the heart at birth (i.e., congenital heart defects, CHD). In this project, genetically engineered mice embryos with selected loss of transforming growth factor beta2 (TGFβ2) gene in the NC (i.e., Tgfb2 CKO) were used and compared with wildtype (i.e., normal TGFβ2 gene) to determine the role of TGFβ2 in NC migration and heart development. The NC were genetically tagged (by combining with mT/mG+/- reporter transgenic mice) by a green-fluorescent protein (GFP) in both Tgfb2 CKO and wildtype embryos to track NC migration and quantification in the heart during embryonic development. Fluorescent microscopic images of serial tissue sections of multiple embryos (three or more embryos/group) from Tgfb2 CKO and wildtype embryos. These images were captured by using GFP filters (green color) in a fluorescent microscope. The amount of GFP fluorescence (green color) was quantified by NIH Image J (Fiji) software. The data showed that the number of GFP-positive NC was significantly increased, and more NC were present in both outflow tract and inflow tract regions in Tgfb2 CKO embryos. In conclusion, the results indicate that TGFβ2 is required for a controlled cardiac NC migration, survival, and proliferation in the heart during embryonic development. This information will lead to a better understanding of the mechanisms involved in congenital heart disease

Effect of Wildfires on Embryonic Development

Wildland Urban Interface (WUI) is “an area where human made structures and infrastructure are in or adjacent to areas prone to wildfire. The purpose of this project is to determine if WUI fires can cause birth defects. Zebrafish (Danio rerio) is an excellent animal model to study the effect of environmental agents and toxins. The hypothesis is that If I treat the zebrafish embryos with the ashes from the WUI Fires, then the embryos will develop birth defects. I used ash samples from Vegetation Fire (rich in Iron) and two types of Structure Fires (rich in zinc and rich in titanium). These ash samples were dissolved in water (2mg/10mL). Each ash sample (200 uL) or water (negative control) was added in a petri dish containing equal number of zebrafish eggs (n = 19) in 4 mL water. Embryonic development was observed daily under a stereozoom light microscope. The results showed that 100% control embryos were normal and born and their hearts were normal. Ash samples rich in Iron (Fe) (Vegetation Fire) and Zinc (Zn) (Structure Fire) developed normally until birth. Ash sample rich in titanium (Ti) (Structure Fire) resulted in delayed embryonic development and 70% of the embryos died before birth. Although the remaining 30% embryos survived past birth, the newborn zebrafish showed abnormal heart. Thus, my experiment revealed that a direct exposure to titanium-rich structure fire ash can pose significant health hazards to life. Bibliography: The Chemistry of Fires at the Wildland-Urban Interface. The National Academies Press. https://doi.org/10.17226/26460