680 research outputs found
Application of Evaporation Method Using Two Tensiometers for Determining Unsaturated Hydraulic Conductivity beyond Tensiometric Range
Accurate determination of unsaturated hydraulic conductivity in low pressure head range is critical for predicting evaporation rate under localized irrigation or root water uptake under drought stress conditions. We proposed a relatively low cost and fast laboratory method to simultaneously determine water retention and hydraulic conductivity functions across a wide range of pressure heads. The method is quite similar to conventional evaporation method using two tensiometers. In addition to tensiometer readings, the proposed method uses water content profile at the end and cumulative evaporation. Experimental results for three soils with different textures showed that inversely optimized hydraulic conductivity functions agreed with K-data measured with the steady state evaporation method, indicating the reliability of the proposed method. The hydraulic conductivity functions fitted for K-data obtained by tensiometer readings with Campbell’s K(θ) function also agreed well with the reference K-data for two of the three soils, but largely deviated from those for the third soil. This indicates the importance of actual measurement of K(θ) in low pressure head range
Direct observation of the current oscillation in a dc SQUID
学術論文 (Article)journal articl
NMR and NQR study of pressure-induced superconductivity and the origin of critical-temperature enhancement in the spin-ladder cuprate SrCaCuO
Pressure-induced superconductivity was studied for a spin-ladder cuprate
SrCaCuO using nuclear magnetic resonance (NMR) under
pressures up to the optimal pressure 3.8 GPa. Pressure application leads to a
transitional change from a spin-gapped state to a Fermi-liquid state at
temperatures higher than . The relaxation rate shows
activated-type behavior at an onset pressure, whereas Korringa-like behavior
becomes predominant at the optimal pressure, suggesting that an increase in the
density of states (DOS) at the Fermi energy leads to enhancement of .
Nuclear quadrupole resonance (NQR) spectra suggest that pressure application
causes transfer of holes from the chain to the ladder sites. The transfer of
holes increases DOS below the optimal pressure. A dome-shaped versus
pressure curve arises from naive balance between the transfer of holes and
broadening of the band width
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Huntingtin-lowering strategies for Huntington's disease.
INTRODUCTION: Huntington's disease (HD) is an incurable, autosomal dominant neurodegenerative disease caused by an abnormally long polyglutamine tract in the huntingtin protein. Because this mutation causes disease via gain-of-function, lowering huntingtin levels represents a rational therapeutic strategy. AREAS COVERED: We searched MEDLINE, CENTRAL, and other trial databases, and relevant company and HD funding websites for press releases until April 2020 to review strategies for huntingtin lowering, including autophagy and PROTACs, which have been studied in preclinical models. We focussed our analyses on oligonucleotide (ASOs) and miRNA approaches, which have entered or are about to enter clinical trials. EXPERT OPINION: ASO and mRNA approaches for lowering mutant huntingtin protein production and strategies for increasing mutant huntingtin clearance are attractive because they target the cause of disease. However, questions concerning the optimal mode of delivery and associated safety issues remain. It is unclear if the human CNS coverage with intrathecal or intraparenchymal delivery will be sufficient for efficacy. The extent that one must lower mutant huntingtin levels for it to be therapeutic is uncertain and the extent to which CNS lowering of wild-type huntingtin is safe is unclear. Polypharmacy may be an effective approach for ameliorating signs and symptoms and for preventing/delaying onset and progression
The degree of aqueous alteration of nine CM chondrites estimated from mineralogy and chemical variations of matrix.
第2回極域科学シンポジウム/第34回南極隕石シンポジウム 11月17日(木) 国立国語研究所 2階講
A quantitative model for IcR product in d-wave Josephson junctions
We study theoretically the Josephson effect in d-wave superconductor /
diffusive normal metal /insulator/ diffusive normal metal/ d-wave
superconductor (D/DN/I/DN/D) junctions. This model is aimed to describe
practical junctions in high- cuprate superconductors, in which the product
of the critical Josephson current () and the normal state resistance ()
(the so-called product) is very small compared to the prediction
of the standard theory. We show that the product in D/DN/I/DN/D
junctions can be much smaller than that in d-wave superconductor / insulator /
d-wave superconductor junctions and formulate the conditions necessary to
achieve large product in D/DN/I/DN/D junctions. The proposed
theory describes the behavior of products quantitatively in
high- cuprate junctions.Comment: 4 pages, 6 figure
Experimental observation of the crystallization of a paired holon state
A new excitation is observed at 201 meV in the doped-hole ladder cuprate
SrCuO, using ultraviolet resonance Raman scattering with
incident light at 3.7 eV polarized along the direction of the rungs. The
excitation is found to be of charge nature, with a temperature independent
excitation energy, and can be understood via an intra-ladder pair-breaking
process. The intensity tracks closely the order parameter of the charge density
wave in the ladder (CDW), but persists above the CDW transition
temperature (), indicating a strong local pairing above .
The 201 meV excitation vanishes in LaCaCuO,
and LaCaCuO which are samples with no holes in the
ladders. Our results suggest that the doped holes in the ladder are composite
bosons consisting of paired holons that order below .Comment: Accepted for publication in Physical Review Letters (4 figures
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