We investigated whether cerebrovascular disease contributes to neurodegeneration and clinical phenotype in dementia with Lewy bodies (DLB). Regional cortical thickness and subcortical gray matter ...volumes were estimated from structural magnetic resonance imaging (MRI) in 165 DLB patients. Cortical and subcortical infarcts were recorded and white matter hyperintensities (WMHs) were assessed. Subcortical only infarcts were more frequent (13.3%) than cortical only infarcts (3.1%) or both subcortical and cortical infarcts (2.4%). Infarcts, irrespective of type, were associated with WMHs. A higher WMH volume was associated with thinner orbitofrontal, retrosplenial, and posterior cingulate cortices, smaller thalamus and pallidum, and larger caudate volume. A higher WMH volume was associated with the presence of visual hallucinations and lower global cognitive performance, and tended to be associated with the absence of probable rapid eye movement sleep behavior disorder. Presence of infarcts was associated with the absence of parkinsonism. We conclude that cerebrovascular disease is associated with gray matter neurodegeneration in patients with probable DLB, which may have implications for the multifactorial treatment of probable DLB.
UCATS (the UAS Chromatograph for Atmospheric Trace Species) was
designed and built for observations of important atmospheric trace gases
from unmanned aircraft systems (UAS) in the upper troposphere ...and lower
stratosphere (UTLS). Initially it measured major chlorofluorocarbons (CFCs)
and the stratospheric transport tracers nitrous oxide (N2O) and sulfur
hexafluoride (SF6), using gas chromatography with electron capture
detection. Compact commercial absorption spectrometers for ozone (O3)
and water vapor (H2O) were added to enhance its capabilities on
platforms with relatively small payloads. UCATS has since been reconfigured
to measure methane (CH4), carbon monoxide (CO), and molecular hydrogen
(H2) instead of CFCs and has undergone numerous upgrades to its
subsystems. It has served as part of large payloads on stratospheric UAS
missions to probe the tropical tropopause region and transport of air into
the stratosphere; in piloted aircraft studies of greenhouse gases,
transport, and chemistry in the troposphere; and in 2021 is scheduled to
return to the study of stratospheric ozone and halogen compounds, one of its
original goals. Each deployment brought different challenges, which were
largely met or resolved. The design, capabilities, modifications, and some
results from UCATS are shown and described here, including changes for
future missions.
Experiments have recently been conducted at the National Ignition Facility utilizing inertial confinement fusion capsule ablators that are 175 and 165 μm in thickness, 10% and 15% thinner, ...respectively, than the nominal thickness capsule used throughout the high foot and most of the National Ignition Campaign. These three-shock, high-adiabat, high-foot implosions have demonstrated good performance, with higher velocity and better symmetry control at lower laser powers and energies than their nominal thickness ablator counterparts. Little to no hydrodynamic mix into the DT hot spot has been observed despite the higher velocities and reduced depth for possible instability feedthrough. Early results have shown good repeatability, with up to 1/2 the neutron yield coming from α-particle self-heating.
Cilia and flagella are microtubule-based structures nucleated by modified centrioles termed basal bodies. These biochemically complex organelles have more than 250 and 150 polypeptides, respectively. ...To identify the proteins involved in ciliary and basal body biogenesis and function, we undertook a comparative genomics approach that subtracted the nonflagellated proteome of
Arabidopsis from the shared proteome of the ciliated/flagellated organisms
Chlamydomonas and human. We identified 688 genes that are present exclusively in organisms with flagella and basal bodies and validated these data through a series of in silico, in vitro, and in vivo studies. We then applied this resource to the study of human ciliation disorders and have identified
BBS5, a novel gene for Bardet-Biedl syndrome. We show that this novel protein localizes to basal bodies in mouse and
C. elegans, is under the regulatory control of
daf-19, and is necessary for the generation of both cilia and flagella.
Dark matter particles could be superheavy, provided their lifetime is much longer than the age of the Universe. Using the sensitivity of the Pierre Auger Observatory to ultrahigh energy neutrinos and ...photons, we constrain a specific extension of the Standard Model of particle physics that meets the lifetime requirement for a superheavy particle by coupling it to a sector of ultralight sterile neutrinos. Our results show that, for a typical dark coupling constant of 0.1, the mixing angle θ m between active and sterile neutrinos must satisfy, roughly, θ m ≲ 1.5 × 10 − 6 ( M X / 10 9 GeV ) − 2 for a mass M X of the dark-matter particle between 10 8 GeV and 10 11 GeV . Published by the American Physical Society 2024
Pilot whalesGlobicephalaspp. have long been thought to be deep divers, yet little information is available on dive depths. During August 1999 we obtained detailed dive data from suction-cup-attached ...time-depth recorder/VHF radio tags deployed on 5 long-finned pilot whalesG. melas. Pilot whales were tagged for short periods (average 5 h ind.–1) in deep (>2000 m) waters of the Ligurian Sea, off the NW coast of Italy. During the day all 5 whales spent their time in the top 16 m of the water column, and visible surface activities consisted primarily of rest and social behaviors. Tags remained attached after dark on 2 whales and shortly after sunset both whales made several deep dives (max. 360 and 648 m). Velocity on these deep dives was greater than during shallow dives either during the day or at night, suggesting that these deep dives function primarily for foraging. Our results confirm the supposition that long-finned pilot whales can dive deep, particularly within 2 h after sunset, which is the time that vertically migrating prey become more readily available as they move closer to the surface.
Due to the introduction of new broadband services, individual line data rates are expected to exceed 100 Gb/s in the near future. To operate at these high speeds, new optical signal processing ...techniques will have to be developed. This paper will demonstrate that two-photon absorption in a specially designed semiconductor microcavity is an ideal candidate for optical signal processing applications such as autocorrelation, sampling, and demultiplexing in high-speed wavelength-division-multiplexed (WDM) and hybrid WDM/optical time-division-multiplexed networks.
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