7,634 research outputs found
Protocol for electrophysiological monitoring of carotid endarterectomies.
Near zero stroke rates can be achieved in carotid endarterectomy (CEA) surgery with selective shunting and electrophysiological neuromonitoring. though false negative rates as high as 40% have been reported. We sought to determine if improved training for interpretation of the monitoring signals can advance the efficacy of selective shunting with electrophysiological monitoring across multiple centers, and determine if other factors could contribute to the differences in reports. Processed and raw beta band (12.5-30 Hz) electroencephalogram (EEG) and median and tibial nerve somatosensory evoked potentials (SSEP) were monitored in 668 CEA cases at six surgical centers. A decrease in amplitude of 50% or more in any EEG or SSEP channel was the criteria for shunting or initiating a neuroprotective protocol. A reduction of 50% or greater in the beta band of the EEG or amplitude of the SSEP was observed in 150 cases. No patient showed signs of a cerebral infarct after surgery. Selective shunting based on EEG and SSEP monitoring can reduce CEA intraoperative stroke rate to a near zero level if trained personnel adopted standardized protocols. We also found that the rapid administration of a protective stroke protocol by attending anesthesiologists was an important aspect of this success rate
The Apparent Anomalous, Weak, Long-Range Acceleration of Pioneer 10 and 11
Recently we reported that radio Doppler data generated by NASA's Deep Space
Network (DSN) from the Pioneer 10 and 11 spacecraft indicate an apparent
anomalous, constant, spacecraft acceleration with a magnitude cm s, directed towards the Sun (gr-qc/9808081). Analysis of
similar Doppler and ranging data from the Galileo and Ulysses spacecraft
yielded ambiguous results for the anomalous acceleration, but it was useful in
that it ruled out the possibility of a systematic error in the DSN Doppler
system that could easily have been mistaken as a spacecraft acceleration. Here
we present some new results, including a critique suggestions that the
anomalous acceleration could be caused by collimated thermal emission. Based
partially on a further data for the Pioneer 10 orbit determination, the data
now spans January 1987 to July 1998, our best estimate of the average Pioneer
10 acceleration directed towards the Sun is cm
s.Comment: Latex, 7 pages and 2 figures. Invited talk at the XXXIV-th Rencontres
de Moriond Meeting on Gravitational Waves and Experimental Gravity. Les Arcs,
Savoi, France (January 23-30,1999). Corrected typo
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Odorant Inhibition in Mosquito Olfaction.
How chemical signals are integrated at the peripheral sensory system of insects is still an enigma. Here we show that when coexpressed with Orco in Xenopus oocytes, an odorant receptor from the southern house mosquito, CquiOR32, generated inward (regular) currents when challenged with cyclohexanone and methyl salicylate, whereas eucalyptol and fenchone elicited inhibitory (upward) currents. Responses of CquiOR32-CquiOrco-expressing oocytes to odorants were reduced in a dose-dependent fashion by coapplication of inhibitors. This intrareceptor inhibition was also manifested in vivo in fruit flies expressing the mosquito receptor CquiOR32, as well in neurons on the antennae of the southern house mosquito. Likewise, an orthologue from the yellow fever mosquito, AaegOR71, showed intrareceptor inhibition in the Xenopus oocyte recording system and corresponding inhibition in antennal neurons. Inhibition was also manifested in mosquito behavior. Blood-seeking females were repelled by methyl salicylate, but repellence was significantly reduced when methyl salicylate was coapplied with eucalyptol
Constraining Cosmology With the CMB LIM-Nulling Convergence
Lensing reconstruction maps from the cosmic microwave background (CMB)
provide direct observations of the matter distribution of the universe without
the use of a biased tracer. Such maps, however, constitute projected
observables along the line of sight that are dominated by their low-redshift
contributions. To cleanly access high-redshift information, Maniyar et al.
showed that a linear combination of lensing maps from both CMB and line
intensity mapping (LIM) observations can exactly null the low-redshift
contribution to CMB lensing convergence. In this paper we explore the
scientific returns of this nulling technique. We show that LIM-nulling
estimators can place constraints on standard CDM plus neutrino mass
parameters that are competitive with traditional CMB lensing. Additionally, we
demonstrate that as a clean probe of the high-redshift universe, LIM-nulling
can be used for model-independent tests of cosmology beyond CDM and as
a probe of the high-redshift matter power spectrum.Comment: 20 pages, 14 figure
A New Probe of the High-z BAO scale: BAO tomography With CMB LIM-Nulling Convergence
Standard rulers such as the baryon acoustic oscillation (BAO) scale serve as
workhorses for precision tests of cosmology, enabling distance measurements
that probe the geometry and expansion history of our Universe. Aside from BAO
measurements from the cosmic microwave background (CMB), most standard ruler
techniques operate at relatively low redshifts and depend on biased tracers of
the matter density field. In a companion paper, we explored the scientific
reach of nulling estimators, where CMB lensing convergence maps are
cross-correlated with linear combinations of similar maps from line intensity
mapping (LIM) to precisely null out the low-redshift contributions to CMB
lensing. We showed that nulling estimators can be used to constrain the high
redshift matter power spectrum and showed that this spectrum exhibits
discernible BAO features. Here we propose using these features as a standard
ruler at high redshifts that does not rely on biased tracers. Forecasting such
a measurement at , we find that next-generation instruments will be
able to constrain the BAO scale to percent-level precision at , while
our futuristic observing scenario can constrain the BAO scale to
precision. This constitutes a fundamentally new kind of BAO measurement during
early epochs in our cosmic history.Comment: 6 pages, 4 figures. arXiv admin note: text overlap with
arXiv:2309.0647
Anderson et al. Reply (to the Comment by Murphy on Pioneer 10/11)
We conclude that Murphy's proposal (radiation of the power of the main-bus
electrical systems from the rear of the craft) can not explain the anomalous
Pioneer acceleration.Comment: LaTex, 3 pages, Phys. Rev. Lett. (to be published
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