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Genetic modification to restore cell functions in the brain can be performed through the delivery of biomolecules in a minimally invasive manner into live neuronal cells within brain tissues. However, conventional nanoscale needles are too short (lengths of ~10 µm) to target neuronal cells in ~1‐mm‐thick brain tissues because the neuronal cells are located deep within the tissue. Here, we report the use of nanoscale‐tipped wire (NTW) arrays with diameters

Transluminal attenuation gradient (TAG) is expected as a noninvasive assessment of the functional significance of a stenosis, and has reported relatively high diagnostic performance. TAG measures the gradient of intraluminal radiological attenuation from the ostium at the first pass of the injected contrast agent; therefore, replacement of fluid by jet flow from a stenosis with gradually increasing contrast agent concentration should be investigated. We performed a phantom experiment and ALE fluid-structure interaction finite element simulation on pulsatile flow through a bifurcated flexible tube system with a stenosis. Experiment and simulation showed good agreement with temporal change of flow rate, pressure, and radius under 1 Hz square pulsatile flow. We varied Young modulus and rate of stenosis with 1 Hz sinusoidal input. Young modulus had little effect on the distribution of total flow, but a changed flow rate waveform and faster maximal velocity in the stenosis was observed with a smaller Young modulus. Then we simulated convection of particle tracers generated at the inlet, imitating a gradual increase in contrast agent with 80% and 95% stenosis. With 80% stenosis, axially symmetric flow resulted in reproductive tracer distributions; however, with 95% stenosis, the direction of jet flow from the stenosis and of subsequent helical flow varied every beat, suggesting this variation might lower sensitivity of TAG.

We detected all components of the deformation potential constants of 4H-SiC by first-principles calculations and developed a method to estimate the stress distribution in 4H-SiC power devices by Finite Element Method (FEM) and Raman spectroscopy. The values of bA1, aE2, and bE2 obtained by calculations agreed well with experimental results, while those of aA1, bE1, and cE2 were about 45% larger. The relationship between phonon frequency and stress was nonlinear as shear stress increased. The multistep FEM analysis reproducing the manufacturing process is also conducted. The stress distribution was converted to the Raman shift and compared with results of micro-Raman spectroscopy. Except for the interface between SiC and the electrode, the analysis results agreed well with the experimental results. It was found that a compressive stress of about 200 MPa at the SiC/electrode interface and a resolved shear stress of about 20 MPa at the epilayer/substrate interface were generated. [ABSTRACT FROM AUTHOR]