793 research outputs found
Taxation Law - Federal Income Taxation - Redemptions and Reorganizations
The Courts of Appeals for the Sixth and Ninth Circuits are in conflict on the question of whether section 351 or section 304 of the Internal Revenue Code of 1954 governs a transfer of the stock of a brother corporation to a sister corporation by the common controlling shareholder in return for stock of the sister corporation and cash.
Coates Trust v. Commissioner of Internal Revenue, 480 F.2d 468 (9th Cir.), cert. denied, 94 S. Ct. 551 (1973).
Commissioner of Internal Revenue v. Stickney, 399 F.2d 838 (6th Cir. 1968)
Scintillator light yield measurements with waveform digitizers
The proton light yield of organic scintillators has been measured extensively
in recent years using fast waveform digitizers and large discrepancies exist in
the values reported by different authors. In this letter, we address principles
of digital signal processing that must be considered when conducting
scintillator light yield measurements. Digitized waveform pulse height values
are only proportional to the amount of scintillation light if the temporal
shape of the scintillation pulse is independent of the amount of energy
deposited. This is not the case for scintillation pulses resulting from fast
neutron interactions in organic scintillators. Authors measuring proton light
yield should therefore report pulse integral values and ensure that the
integration length is long enough to capture most of the scintillation light.Comment: 6 pages, 2 figure
Evaluation of Bicanalicular Nasolacrimal Duct Intubation as an Adjunct in Surgical Ectropion Correction.
Background and Objectives: We aimed to analyze and compare the outcomes of conventional ectropion surgery procedures with and without concurrent bicanalicular nasolacrimal duct intubation to identify if the combination of procedures could serve as a novel surgical approach to treat lower eyelid ectropion. Materials and Methods: A retrospective review of all patients who underwent surgical correction for lower eyelid ectropion at the Cantonal Hospital of Aarau between January 2019 and December 2020 was performed. Patient medical records were examined for etiology, surgical correction technique and intra- and postoperative complications. The postoperative punctal position, the pre- and postoperative epiphora and reoperation rate were also documented. Two study groups consisting of cases with isolated and combined procedures were compared, with respect to postoperative punctual and lower lid position. Results: A total of 53 lower eyelids (35 patients) were included in this study. Six months postoperatively, the correct punctum position (p = 0.1188) and improvement of epiphora (p = 0.7739) did not significantly differ between the two groups. More complications were seen in the nasolacrimal duct intubation group (p = 0.0041), which consisted of cheese wiring and one tube dislocation. Conclusion: In our study, bicanalicular nasolacrimal intubation during ectropion surgery does not seem to improve the outcome of ectropion surgery and is, therefore, not recommended on a routine basis
Structural diversity in the type IV pili of multidrug-resistant Acinetobacter
Acinetobacter baumannii is a Gram-negative coccobacillus found primarily in hospital settings that has recently emerged as a source of hospital-acquired infections. A. baumannii expresses a variety of virulence factors, including type IV pili, bacterial extracellular appendages often essential for attachment to host cells. Here, we report the high resolution structures of the major pilin subunit, PilA, from three Acinetobacter strains, demonstrating thatA. baumannii subsets produce morphologically distinct type IV pilin glycoproteins. We examine the consequences of this heterogeneity for protein folding and assembly as well as host-cell adhesion by Acinetobacter. Comparisons of genomic and structural data with pilin proteins from other species of soil gammaproteobacteria suggest that these structural differences stem from evolutionary pressure that has resulted in three distinct classes of type IVa pilins, each found in multiple species
Absolute light yield of the EJ-204 plastic scintillator
The absolute light yield of a scintillator, defined as the number of
scintillation photons produced per unit energy deposited, is a useful quantity
for scintillator development, research, and applications. Yet, literature data
on the absolute light yield of organic scintillators are limited. The goal of
this work is to assess the suitability of the EJ-204 plastic scintillator from
Eljen Technology to serve as a reference standard for measurements of the
absolute light yield of organic scintillators. Four EJ-204 samples were
examined: two manufactured approximately four months prior and stored in
high-purity nitrogen, and two aged approximately eleven years and stored in
ambient air. The scintillator response was measured using a large-area
avalanche photodiode calibrated using low energy -ray and X-ray
sources. The product of the quantum efficiency of the photodetector and light
collection efficiency of the housing was characterized using an
experimentally-benchmarked optical photon simulation. The average absolute
light yield of the fresh samples, 9100 400 photons per MeV, is lower than
the manufacturer-reported value of 10400 photons per MeV. Moreover, the aged
samples demonstrated significantly lower light yields, deviating from the
manufacturer specification by as much as 26\%. These results are consistent
with recent work showcasing environmental aging in plastic scintillators and
suggest that experimenters should use caution when deploying plastic
scintillators in photon counting applications.Comment: 12 pages, 9 figure
Measurement of proton light yield of water-based liquid scintillator
The proton light yield of liquid scintillators is an important property in
the context of their use in large-scale neutrino experiments, with direct
implications for neutrino-proton scattering measurements and the discrimination
of fast neutrons from inverse beta-decay coincidence signals. This work
presents the first measurement of the proton light yield of a water-based
liquid scintillator (WbLS) formulated from 5% linear alkyl benzene (LAB), at
energies below 20 MeV, as well as a measurement of the proton light yield of a
pure LAB + 2 g/L 2,5-diphenyloxazole (PPO) mixture (LABPPO). The measurements
were performed using a double time-of-flight method and a pulsed neutron beam
from the 88-Inch Cyclotron at Lawrence Berkeley National Laboratory. The proton
light yields were measured relative to that of a 477 keV electron. The relative
proton light yield of WbLS was approximately 3.8% lower than that of LABPPO,
itself exhibiting a relative proton light yield higher than previous
measurements of an analogous anoxic sample. The observed quenching is not
compatible with the Birks model for either material, but is well described with
the addition of Chou's bimolecular quenching term.Comment: 14 pages, 11 figure
Measurement of Proton Light Yield of Water-based Liquid Scintillator
The proton light yield of liquid scintillators is an important property in the context of their use in large-scale neutrino experiments, with direct implications for neutrino-proton scattering measurements and the discrimination of fast neutrons from inverse β-decay coincidence signals. This work presents the first measurement of the proton light yield of a water-based liquid scintillator (WbLS) formulated from 5% linear alkyl benzene (LAB), at energies below 20 MeV, as well as a measurement of the proton light yield of a pure LAB + 2 g/L 2,5-diphenyloxazole (PPO) mixture (LABPPO). The measurements were performed using a double time-of-flight method and a pulsed neutron beam from the 88-Inch Cyclotron at Lawrence Berkeley National Laboratory. The proton light yields were measured relative to that of a 477 keV electron. The relative proton light yield of WbLS was approximately 3.8% lower than that of LABPPO, itself exhibiting a relative proton light yield 15–20% higher than previous measurements of an analogous anoxic sample. The observed quenching is not compatible with the Birks model for either material, but is well described with the addition of Chou’s bimolecular quenching term. © 2023, The Author(s)
Comparison of the ICare® rebound tonometer with the Goldmann tonometer in a normal population
The aim of this study was to evaluate the accuracy of measurement of intraocular pressure (IOP) using a new induction/impact rebound tonometer (ICare) in comparison with the Goldmann applanation tonometer (AT). The left eyes of 46 university students were assessed with the two tonometers, with induction tonometry being performed first. The ICare was handled by an optometrist and the Goldmann tonometer by an ophthalmologist. In this study, statistically significant differences were found when comparing the ICare rebound tonometer with applanation tonometry (AT) (p < 0.05). The mean difference between the two tonometers was 1.34 +/- 2.03 mmHg (mean +/- S.D.) and the 95% limits of agreement were +/-3.98 mmHg. A frequency distribution of the differences demonstrated that in more than 80% of cases the IOP readings differed by <3 mmHg between the ICare and the AT. In the present population the ICare overestimates the IOP value by 1.34 mmHg on average when compared with Goldmann tonometer. Nevertheless, the ICare tonometer may be helpful as a screening tool when Goldmann applanation tonometry is not applicable or not recommended, as it is able to estimate IOP within a range of +/-3.00 mmHg in more than 80% of the populatio
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