657 research outputs found
Surveyor ejecta detector model ML 256-1 and 185-1 and Surveyor ejecta detector ground support equipment model ML 260-1 Final engineering report
Engineering analyses on Surveyor lunar dust particle detector instrumentation, and ground support equipmen
Understanding and reducing the disaster risk of landslide-induced tsunamis: a short summary of the panel discussion in the World Tsunami Awareness Day Special Event of the Fifth World Landslide Forum
A World Tsunami Awareness Day Special Event was held in hybrid mode on 5 November 2021, during the Fifth World Landslide Forum, in Kyoto, Japan. In this context, a panel discussion was organized across America, Europe, and Asia, with the goal to better understand and reduce the disaster risk of landslide-induced tsunamis, consistent with the Kyoto Landslide Commitment 2020. This article presents a short summary of this panel discussion
Identification and functional analysis of pistil self-incompatibility factor HT-B of Petunia
Gametophytic self-incompatibility (GSI) in Solanaceae, Rosaceae, and Plantaginaceae is controlled by a multiallelic S-locus. The specificities of pistil and pollen are controlled by separate S-locus genes, S-RNase and SLF/SFB, respectively. Although the S-specificity is determined by the S-locus genes, factors located outside the S-locus are also required for expression of GSI. HT-B is one of the pistil non-S-factors identified in Nicotiana and Solanum, and encodes a small asparagine/aspartate-rich extracellular protein with unknown biochemical function. Here, HT-B was cloned from Petunia and characterized. The structural features and expression pattern of Petunia HT-B were very similar to those of Nicotiana and Solanum. Unlike other solanaceous species, expression of HT-B was also observed in self-compatible Petunia species. RNA interference (RNAi)-mediated suppression of Petunia HT-B resulted in partial breakdown of GSI. Quantitative analysis of the HT-B mRNA accumulation in the transgenics showed that a 100-fold reduction is not sufficient and a >1000-fold reduction is required to achieve partial breakdown of GSI
Electronic structure near the 1/8-anomaly in La-based cuprates
We report an angle resolved photoemission study of the electronic structure
of the pseudogap state in \NdLSCO ( K). Two opposite dispersing Fermi
arcs are the main result of this study. The several scenarios that can explain
this observation are discussed.Comment: A high-resolution version can be found at
http://lns.web.psi.ch/lns/download/Pockets/arXiv.pd
Spectroscopic evidence for preformed Cooper pairs in the pseudogap phase of cuprates
Angle-resolved photoemission on underdoped LaSrCuO
reveals that in the pseudogap phase, the dispersion has two branches located
above and below the Fermi level with a minimum at the Fermi momentum. This is
characteristic of the Bogoliubov dispersion in the superconducting state. We
also observe that the superconducting and pseudogaps have the same d-wave form
with the same amplitude. Our observations provide direct evidence for preformed
Cooper pairs, implying that the pseudogap phase is a precursor to
superconductivity
Origins of large critical temperature variations in single layer cuprates
We study the electronic structures of two single layer superconducting
cuprates, TlBaCuO (Tl2201) and
(BiPb)(SrLa)CuO (Bi2201) which
have very different maximum critical temperatures (90K and 35K respectively)
using Angular Resolved Photoemission Spectroscopy (ARPES). We are able to
identify two main differences in their electronic properties. First, the shadow
band that is present in double layer and low T single layer cuprates
is absent in Tl2201. Recent studies have linked the shadow band to structural
distortions in the lattice and the absence of these in Tl2201 may be a
contributing factor in its T.Second, Tl2201's Fermi surface (FS)
contains long straight parallel regions near the anti-node, while in Bi2201 the
anti-nodal region is much more rounded. Since the size of the superconducting
gap is largest in the anti-nodal region, differences in the band dispersion at
the anti-node may play a significant role in the pairing and therefore affect
the maximum transition temperature.Comment: 6 pages, 5 figures,1 tabl
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