74,210 research outputs found
Photoelectric energy spectrometer Patent
Spectrometer using photoelectric effect to obtain spectral dat
Friends with Benefits: Redefining Personal Gain in Insider Trading Under Salman v. United States
Since Congress has not enacted a statute outlawing insider trading, or the trading of securities based on non-public information, outright, courts have struggled to define what constitutes insider trading. The Supreme Court held that a fiduciary duty was breached when the insider privy to the information receives a “personal benefit.” This Commentary analyzes a pending Supreme Court case, Salman v. United States, which addresses whether pecuniary gain is needed to constitute the personal benefit necessary for insider trading, or if certain relationships are enough for the tip to inherently create a personal benefit for the insider. The author argues that a “personal benefit” can occur when there is (1) a quid pro quo or (2) the relationship between insider and tippee is intimate enough to automatically lead to a benefit for the insider. This conclusion follows Supreme Court precedent and is consistent with the policies for outlawing insider trading
Photochromism of dihydroquinolines
Reversible photochromic reactions, in which absorption spectrum of chemical compound may be shifted by application of visible or ultraviolet light, and then returned to original state by heating, are observed for certain members of 1,2-dihydroquinoline family. Structural formulas for colorless and colored states are given
Analysis of solar panel effect on louver performance
Mathematical analysis of solar panel effect on temperature control of spacecraft in solar heat environmen
X-rays from the Eclipsing Millisecond Pulsar PSR J1740-5340 in the Globular Cluster NGC 6397
The millisecond pulsar PSR J1740-5340 in the globular cluster NGC 6397 shows
radio eclipses over ~40% of its binary orbit. A first Chandra observation
revealed indications for the X-ray flux being orbit dependent as well. In this
work we analysed five data sets of archival Chandra data taken between 2000 and
2007 in order to investigate the emission across the pulsar's binary orbit.
Utilizing archival Chandra observations of PSR J1740-5340, we have performed a
systematic timing and spectral analysis of this binary system. Using a
chi-square-test the significance for intra-binary orbital modulation is found
to be between 88.5% and 99.6%, depending on the number of phase bins used to
construct the light curve. Applying the unbiased statistical Kolmogorov-Smirnov
(KS) test did not indicate any significant intra-binary orbital modulation,
though. However, comparing the counting rates observed at different epochs a
flux variability on times scales of days to years is indicated. The possible
origin of the X-ray emission is discussed in a number of different scenarios.Comment: 5 pages, 4 figures. Accepted for publication in Astronomy and
Astrophysic
Molecular and functional characterization of gap junctions in the avian inner ear.
To analyze the fundamental role of gap junctions in the vertebrate inner ear, we examined molecular and functional characteristics of gap junctional communication (GJC) in the auditory and vestibular system of the chicken. By screening inner ear tissues for connexin isoforms using degenerate reverse transcription-PCR, we identified, in addition to chicken Cx43 (cCx43) and the inner-ear-specific cCx30, an as yet uncharacterized connexin predicted to be the ortholog of the mammalian Cx26. In situ hybridization indicated that cCx30 and cCx26 transcripts were both widely expressed in the cochlear duct and utricle in an overlapping pattern, suggesting coexpression of these isoforms similar to that in the mammalian inner ear. Immunohistochemistry demonstrated that cCx43 was present in gap junctions connecting supporting cells of the basilar papilla, in which its immunofluorescence colocalized with that of cCx30. However, cCx43 was absent from supporting cell gap junctions of the utricular macula. This variation in the molecular composition of gap junction plaques coincided with differences in the functional properties of GJC between the auditory and vestibular sensory epithelia. Fluorescence recovery after photobleaching, adapted to examine the diffusion of calcein in inner ear explants, revealed asymmetric communication pathways among supporting cells in the basilar papilla but not in the utricular macula. This study supports the hypothesis that the coexpression of Cx26/Cx30 is unique to gap junctions in the vertebrate inner ear. Furthermore, it demonstrates asymmetric GJC within the supporting cell population of the auditory sensory epithelium, which might mediate potassium cycling and/or intercellular signaling
Acoustic source location in a jet-blown flap using a cross-correlation technique
The acoustic source strength distribution in a turbulent flow field was measured for two far field microphones at 45 deg above and below the plane of the flap surface. A processed signal from an inclined hot-film anemometry probe was cross correlated with the signal from the appropriate far field microphone. The contribution made by the sources associated with the fluctuating pressure on the flap surface to the sound received at far field microphone was estimated by cross correlating the processed signals of microphones which were embedded in the flap surface with the far field microphone signals. In addition, detailed fluid dynamic measurements were made in the flow field of the jet flap using dual sensor hot-film anemometry probes
Variational analysis of self-focusing of intense ultrashort pulses in gases
By using perturbation theory we derive an expression for the electrical field
of a Gaussian laser pulse propagating in a gas medium. This expression is used
as a trial solution in a variational method to get quasianalytical solutions
for the width, intensity and self-focusing distance of ultrashort pulse. The
approximation gives an improved agreement with results of numerical simulations
for a broad range of values of the input power of the pulse than previous
analytical results available in the literature.Comment: 19 pages, 8 figure
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