3,027 research outputs found
Kidney Development in Eleutherodactylus coqui With Relation to Edema Syndrome
Vertebrates develop embryonic kidneys before the final adult kidney. Particularly for organisms with aquatic larvae such as frogs, the first embryonic kidney, the pronephros is essential for the larvae\u27s survival. Those larvae with defective or without pronephroi exhibited pronounced edema. Edema is severe swelling of a body part as a result of fluid retention. To date, although the embryonic kidneys have been extensively studied in various model organisms, it has not been studied in Eleutherodactylus coqui. E. coqui is a direct developing frog and lacks a tadpole phase in its life cycle. I examined the kidney development in E. coqui using endogenous alkaline phosphatase staining and histology. From the histology, I found that E. coqui embryos develop a pronephros followed by the mesonephros in normal development. The endogenous alkaline phosphatase staining was a novel finding and a good marker for early pronephric development in E. coqui. The kidney development in E. coqui embryos exhibiting edema was also studied. The key characteristic in the edematous embryos was the large lumens of the tubules. The edematous embryos also had poor limb development. I speculate that the edema in the E. coqui embryos was due to a defective pronephros, however, it is a correlation in the scope of this study and other causal possibilities are considered such as defects in the lymphatic system, the circulatory system and the skin. The possible relations between limb and kidney development is also discussed
Existence of an unbounded branch of the set of solutions for Neumann problems involving the p(x)-Laplacian
MProtect: Operating System Memory Management without Access
Modern operating systems (OSes) have unfettered access to application data,
assuming that applications trust them. This assumption, however, is problematic
under many scenarios where either the OS provider is not trustworthy or the OS
can be compromised due to its large attack surface. Our investigation began
with the hypothesis that unfettered access to memory is not fundamentally
necessary for the OS to perform its own job, including managing the memory. The
result is a system called MProtect that leverages a small piece of software
running at a higher privilege level than the OS. MProtect protects the entire
user space of a process, requires only a small modification to the OS, and
supports major architectures such as ARM, x86 and RISC-V. Unlike prior works
that resorted to nested virtualization, which is often undesirable in mobile
and embedded systems, MProtect mediates how the OS accesses the memory and
handles exceptions. We report an implementation of MProtect called MGuard with
ARMv8/Linux and evaluate its performance with both macro and microbenchmarks.
We show MGuard has a runtime TCB 2~3 times smaller than related systems and
enjoys competitive performance while supporting legitimate OS access to the
user space
Low-temperature synthesis of CuO-interlaced nanodiscs for lithium ion battery electrodes
In this study, we report the high-yield synthesis of 2-dimensional cupric oxide (CuO) nanodiscs through dehydrogenation of 1-dimensional Cu(OH)2 nanowires at 60°C. Most of the nanodiscs had a diameter of approximately 500 nm and a thickness of approximately 50 nm. After further prolonged reaction times, secondary irregular nanodiscs gradually grew vertically into regular nanodiscs. These CuO nanostructures were characterized using X-ray diffraction, transmission electron microscopy, and Brunauer-Emmett-Teller measurements. The possible growth mechanism of the interlaced disc CuO nanostructures is systematically discussed. The electrochemical performances of the CuO nanodisc electrodes were evaluated in detail using cyclic voltammetry and galvanostatic cycling. Furthermore, we demonstrate that the incorporation of multiwalled carbon nanotubes enables the enhanced reversible capacities and capacity retention of CuO nanodisc electrodes on cycling by offering more efficient electron transport paths
Cellular sprayed concrete for simple and economic remixing
The development of various supplementary cementitious materials (SCMs) and chemical admixtures, makes the manufacturing of high-performance shotcrete possible. The most important SCM in high-performance shotcrete is silica fume because of its effect on pumpability, high-strength and durability which lies in its Pozzolanic reaction. Furthermore, the very small particle size of silica fume reacts more quickly than other SCMs and acts as a filler which contributes to the nano-sized porosity occurring in the interfacial transition zone. On the other hand, because of the extremely small particle size of silica fume, it is used as a pre-blended type with a Portland cement for a better distribution of silica fume in concrete. This results in a high cost material. If it is possible to distribute the very fine silica fume in a ready-mixed concrete, this would results in a very simple and an economic way. A very innovative method, which was named as Cellular sprayed concrete, was developed. Cellular sprayed concrete is a process to produce a High-Performance Concrete (HPC) by adding cellular and silica fume in ready-mixed concrete. This method enable to distribute the very fine silica fume in a ready-mixed concrete. This paper describe on the very new and innovative concept and procedures of cellular sprayed concrete
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