We observed a conductive filament in CBRAM (conductive bridging RAM) during switching operations by in-situ TEM (transmission electron microscopy) method. A vertically stacked-type CBRAM is popular ...for TEM observation, however, we used a lateral-type CBRAM (Cu-WOX-Cu CBRAM) for clearer TEM observations. In a Set operation (resistive switching from the high resistance state (HRS) to the low resistance state (LRS)), a conductive filament grew from a cathode to an anode and increase of Cu in the cathode was observed. After the Set operation, a Reset operation (resistive switching from LRS to HRS) was observed in the opposite voltage polarity to the former Set but big structural changes were not seen. The growth direction of Cu conductive filament and increase of Cu in the cathode after the Set can be explained by a proposed switching model of CBRAM (conductive filament model).
The performance of a muon radiography system designed to image the inner structure of a nuclear plant located at a distance of 64 m is evaluated. We conclude that there is an absence of fuel in the ...pressure vessel during the measurement period and profile the fuel material placed in the storage pool. The obtained data also demonstrate the sensitivity of the system to water-level changes in the reactor well and the dryer-separator pool. It is expected that the system could easily reconstruct a 2 m cubic fuel object. By operating multiple systems, typically four identical systems, viewing the reactor from different directions simultaneously, detection of a 1 m cubic object should also be achievable within a period of a few months.
We have investigated the crystal growth of single-phase MnSi
1.75−
x
by a temperature gradient solution growth (TGSG) method using Ga and Sn as solvents and MnSi
1.7
alloy as the solute, and measured ...the thermoelectric properties of the resulting crystals. Single-phase Mn
11
Si
19
and Mn
4
Si
7
crystals were grown successfully using Ga and Sn as solvents, respectively. The typical size of a grown ingot of Mn
11
Si
19
was 2 mm to 4 mm in thickness and 12 mm in diameter, whereas Mn
4
Si
7
had polyhedral shape with dimensions in the range of several millimeters. The single-phase Mn
11
Si
19
has good electrical conduction (
ρ
= 0.89 × 10
−3
Ω cm to 1.09 × 10
−3
Ω cm) compared with melt-grown multiphase higher-manganese silicide (HMS) crystals. The Seebeck coefficient, power factor, and thermal conductivity were 77
μ
V K
−1
to 85
μ
V K
−1
, 6.7
μ
W cm
−1
K
−2
to 7.2
μ
W cm
−1
K
−2
, and 0.032 W cm
−1
K
−1
, respectively, at 300 K.
We propose a new method of spin squeezing of atomic spin, based on the interactions between atoms and off-resonant light which are known as paramagnetic Faraday rotation and the fictitious magnetic ...field of light. Since the projection process, squeezed light, or special interactions among the atoms are not required in this method, it can be widely applied to many systems. The attainable range of the squeezing parameter is zeta greater, similarS(-2/5), where S is the total spin, which is limited by additional fluctuations imposed by coherent light and the spherical nature of the spin distribution.
Hypoxia-inducible factor-1 (HIF-1) is a ubiquitously expressed oxygen-regulated transcription factor composed of α and β subunits. HIF-1 activates transcription of various genes including those ...involved in metastatic tumor growth. In the present study, HIF-1α expression in tumor-bearing mouse liver was examined after inoculation of tumor cells into portal vein. We found that tumor-bearing liver showed greatly increased HIF-1α expression. Plasmid DNA (pDNA) expressing short hairpin RNA targeting HIF-1α (pshHIF-1α) was effective in suppressing protein expression of HIF-1α in vitro. Intravenous injection of pshHIF-1α by hydrodynamics-based procedure reduced the HIF-1α protein expression in both normal and tumor cells and tumor cell number in the liver. Pre-injection of pshHIF-1α to mice, by which pDNA was delivered only to liver cells, not to tumor cells, was also effective in reducing the number of tumor cells inoculated 3 days after pDNA injection. These findings indicate that HIF-1α expression is increased in normal liver cells as well as tumor cells, and HIF-1α expression plays an important role in tumor progression. Use of the RNA interference (RNAi) of HIF-1 is an effective strategy for inhibiting tumor cell growth, and both tumor and normal cells can be the target for RNAi-based anticancer treatment.
The existing non-destructive inspection method employed for concrete structures uses high energy X-rays to detect internal flaws in concrete structures and iron reinforcing rods. In addition to this ...conventional method, the authors are developing an innovative inspection system that uses a mobile compact linac-driven neutron source that utilizes neutron backscattering, to measure the moisture distribution in concrete structures and estimate the corrosion probability distribution of iron reinforcing rods.
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