1,506 research outputs found
Taxation—City Sales Tax—Liability of Vendor
W. T. Grant Company v. Joseph, 2 N.Y.2d 196, 159 N.Y.S.2d 150 (1957)
Decedent\u27s Estates—Charitable Bequests—Liberal Construction
In re Ablett\u27s Will, 3 N.Y.2d 261, 165 N.Y.S.2d 63 (1957); In re Perkin\u27s Will, 3 N.Y.2d 281, 165 N.Y.S.2d 77 (1937); In re Bishop\u27s Will, 3 N.Y.2d 294, 165 N.Y.S.2d 86 (1957)
Bose-Einstein condensation at constant temperature
We present a novel experimental approach to Bose-Einstein condensation by
increasing the particle number of the system at almost constant temperature. In
particular the emergence of a new condensate is observed in multi-component F=1
spinor condensates of 87-Rb. Furthermore we develop a simple rate-equation
model for multi-component BEC thermodynamics at finite temperature which well
reproduces the measured effects.Comment: 4 pages, 3 figures, RevTe
A laser-driven target of high-density nuclear polarized hydrogen gas
We report the best figure-of-merit achieved for an internal nuclear polarized
hydrogen gas target and a Monte Carlo simulation of spin-exchange optical
pumping. The dimensions of the apparatus were optimized using the simulation
and the experimental results were in good agreement with the simulation. The
best result achieved for this target was 50.5% polarization with 58.2% degree
of dissociation of the sample beam exiting the storage cell at a hydrogen flow
rate of atoms/s.Comment: Accepted as a Rapid Communication article in Phys. Rev.
Midodrine as a Countermeasure for Post-Spaceflight Orthostatic Hypotension
One possible mechanism for post-spaceflight orthostatic hypotension, which affects approximately 30% of astronauts after short duration shuttle missions, is inadequate norepinephrine release during upright posture. We performed a two phased study to determine the effectiveness of an alpha1-adrenergic agonist, midodrine, as a countermeasure to post-spaceflight orthostatic hypotension. The first phase of the study examined the landing day orthostatic responses of six veteran astronauts after oral midodrine (10 mg) administered on the ground within approximately two hours of wheel stop. One female crewmember exhibited orthostatic hypotension in a previous flight but not after midodrine. Five male crewmembers, who did not exhibit orthostatic hypotension during previous flights, also did not show signs of orthostatic hypotension after midodrine. Additionally, phase one showed that midodrine did not cause hypertension in these crewmembers. In the second phase of this study, midodrine is ingested inflight (near time of ignition, TIG) and orthostatic responses are determined immediately upon landing via an 80 degree head-up tilt test performed on the crew transport vehicle (CTV). Four of ten crewmembers have completed phase two of this study. Two crewmembers completed the landing day tilt tests, while two tests were ended early due to presyncopal symptoms. All subjects had decreased landing day stroke volumes and increased heart rates compared to preflight. Midodrine appears to have increased total peripheral resistance in one crewmember who was able to complete the landing day tilt test. The effectiveness of midodrine as a countermeasure to immediate post-spaceflight orthostatic hypotension has yet to be determined; interpretation is made more difficult due to low subject number and the lack of control subjects on the CTV
Lower Limb Venous Compliance is Different Between Men and Women Following 60 Days of Head-Down Bedrest but Is Not Associated with Venoconstriction Dysfunction
Space flight-induced orthostatic intolerance (OI) is more prevalent in female (F) than male (M) astronauts. The mechanisms explaining the higher incidence of OI in F are unclear. We tested the hypothesis that venous compliance would be higher in F more than M following 6 deg head-down bed rest (BR) and would be associated with constrictor dysfunction. Using 2-D ultrasound, dorsal hand (DHV) and dorsal foot (DFV) vein compliances were determined in 24 subjects (10 F, 14 M; 35 +/- 1 yr) by measuring mean diameter response to increasing congestion pressure (0, 20, 30, and 40 mmHg) before and after 60 d of BR. Constrictor function was assessed by intravenous infusions of Ketorolac (KE; 1.5 ig/min) Phenylephrine (PE; 3160 ng/min), and L-NMMA (50 ig/min). The effects of BR between F vs. M and hand vs. foot were determined using mixed-effects linear regression. DFV but not DHV compliance changed in response to BR (p=0.012). Mean DFV increased significantly (0.903 mm to 1.191mm) in F but decreased in M (1.353 mm to 1.154 mm). DFV constrictor response was not different between sexes in response to BR (KE; p=0.647, PE; p=0.717, and L-NMMA; p=0.825). These BR data suggest that the higher incidence of OI in F astronauts may be related to increased lower limb venous compliance, contributing to blood pooling upon standing. Notably, changes to DFV compliance was not accompanied by impaired constrictor function
Laser frequency stabilization to a single ion
A fundamental limit to the stability of a single-ion optical frequency
standard is set by quantum noise in the measurement of the internal state of
the ion. We discuss how the interrogation sequence and the processing of the
atomic resonance signal can be optimized in order to obtain the highest
possible stability under realistic experimental conditions. A servo algorithm
is presented that stabilizes a laser frequency to the single-ion signal and
that eliminates errors due to laser frequency drift. Numerical simulations of
the servo characteristics are compared to experimental data from a frequency
comparison of two single-ion standards based on a transition at 688 THz in
171Yb+. Experimentally, an instability sigma_y(100 s)=9*10^{-16} is obtained in
the frequency difference between both standards.Comment: 15 pages, 5 figures, submitted to J. Phys.
Ultra-precise measurement of optical frequency ratios
We developed a novel technique for frequency measurement and synthesis, based
on the operation of a femtosecond comb generator as transfer oscillator. The
technique can be used to measure frequency ratios of any optical signals
throughout the visible and near-infrared part of the spectrum. Relative
uncertainties of for averaging times of 100 s are possible. Using a
Nd:YAG laser in combination with a nonlinear crystal we measured the frequency
ratio of the second harmonic at 532 nm to the fundamental at
1064 nm, .Comment: 4 pages, 4 figure
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