9,325 research outputs found
Zero kinetic energy-pulsed field ionization and resonance enhanced multiphoton ionization photoelectron spectroscopy: Ionization dynamics of Rydberg states in HBr
The results of rotationally resolved resonance enhanced multiphoton ionization photoelectron spectroscopy and zero kinetic energyâpulsed field ionization studies on HBr via various rotational levels of the F^â1Î_2 and f^â3Î_2 Rydberg states are reported. These studies lead to an accurate determination of the lowest ionization threshold as 94â098.9±1 cm^(â1). Observed rotational and spinâorbit branching ratios are compared to the results of ab initio calculations. The differences between theory and experiment highlight the dominant role of rotational and spinâorbit interactions for the dynamic properties of the highân Rydberg states involved in the pulsed field ionization process
Surgery using plasma energy for deep endometriosis: A quality of life assessment
OBJECTIVE: The principal objective of our study was to assess women\u27s quality of life (QoL) after surgery for Deep Endometriosis (DE), according to the surgical technique used.
MATERIAL AND METHODS: Qualitative single-center survey in the department of obstetrics and gynecology, Angers University Hospital Center, France. All women who underwent surgery for DE from January 2011 to December 2015 were contacted by phone. The Endometriosis Health Profile-5 score was used to assess QoL before and after the surgery. Fifty-two women (response rate=86%) were included and classified into 3 groups according to the surgical technique used: simple shaving, shaving exclusively or in part by plasma vaporization (plasma), and resection.
RESULTS: The 3 groups were comparable for surgical history, preoperative QoL score, and characteristics of endometriotic lesions (size and site). All DE symptoms and QoL scores improved significantly after the surgery, all techniques combined (P<0.01). QoL scores for women who had plasma shaving or complete resection were significantly higher than those for women with simple shaving (respectively, 375 [225-800] and 450 [-50 to 725] vs 275 [-100 to 600]; P=0.04). Self-image significantly improved only in the plasma group (P=0.03). The complete resection group had longer hospitals stays than the other groups (P=0.001), as well as a higher surgical revision rate (23% vs 0%; P=0.02).
CONCLUSION: Plasma and complete resection improved QoL similarly for women with DE, both more than shaving alone. The advantage of plasma vaporization lies in the lesser morbidity and better self-image, both better than in women with resection
Tuning the exciton g-factor in single InAs/InP quantum dots
Photoluminescence data from single, self-assembled InAs/InP quantum dots in
magnetic fields up to 7 T are presented. Exciton g-factors are obtained for
dots of varying height, corresponding to ground state emission energies ranging
from 780 meV to 1100 meV. A monotonic increase of the g-factor from -2 to +1.2
is observed as the dot height decreases. The trend is well reproduced by sp3
tight binding calculations, which show that the hole g-factor is sensitive to
confinement effects through orbital angular momentum mixing between the
light-hole and heavy-hole valence bands. We demonstrate tunability of the
exciton g-factor by manipulating the quantum dot dimensions using pyramidal InP
nanotemplates
Development and Characterisation of a Gas System and its Associated Slow-Control System for an ATLAS Small-Strip Thin Gap Chamber Testing Facility
A quality assurance and performance qualification laboratory was built at
McGill University for the Canadian-made small-strip Thin Gap Chamber (sTGC)
muon detectors produced for the 2019-2020 ATLAS experiment muon spectrometer
upgrade. The facility uses cosmic rays as a muon source to ionise the quenching
gas mixture of pentane and carbon dioxide flowing through the sTGC detector. A
gas system was developed and characterised for this purpose, with a simple and
efficient gas condenser design utilizing a Peltier thermoelectric cooler (TEC).
The gas system was tested to provide the desired 45 vol% pentane concentration.
For continuous operations, a state-machine system was implemented with alerting
and remote monitoring features to run all cosmic-ray data-acquisition
associated slow-control systems, such as high/low voltage, gas system and
environmental monitoring, in a safe and continuous mode, even in the absence of
an operator.Comment: 23 pages, LaTeX, 14 figures, 4 tables, proof corrections for Journal
of Instrumentation (JINST), including corrected Fig. 8b
Treatment of endometriosis by aromatase inhibitors: efficacy and side effects
The recent demonstration that aromatase is expressed at higher levels in endometriosis implants than in normal endometrium has led to pilot studies using inhibitor aromatasis in patients with endometriosis. We conducted a systematic review of the literature and studied the efficacy of aromatase inhibitors on endometriosis. There were seventeen studies (case reports/series) evaluating outcomes of aromatase inhibitors. Studies suggest that aromatase inhibitors alone or co-administered with progestins, oral contraceptives or gonadotrophin releasing hormone (GnRH) agonist could reduce pain and endometriosis. There is only one randomized controlled trial comparing aromatase inhibitor+GnRH agonist and GnRH agonist and one study with eighty patients. Side-effects profiles of aromatase inhibitor regimens are favorable; it does not appear a significant bone loss. Aromatase inhibitors seem to have a promising effect on endometriosis but randomized controlled trials are needed to prove their effects and their safety
How does the substrate affect the Raman and excited state spectra of a carbon nanotube?
We study the optical properties of a single, semiconducting single-walled
carbon nanotube (CNT) that is partially suspended across a trench and partially
supported by a SiO2-substrate. By tuning the laser excitation energy across the
E33 excitonic resonance of the suspended CNT segment, the scattering
intensities of the principal Raman transitions, the radial breathing mode
(RBM), the G-mode and the D-mode show strong resonance enhancement of up to
three orders of magnitude. In the supported part of the CNT, despite a loss of
Raman scattering intensity of up to two orders of magnitude, we recover the E33
excitonic resonance suffering a substrate-induced red shift of 50 meV. The peak
intensity ratio between G-band and D-band is highly sensitive to the presence
of the substrate and varies by one order of magnitude, demonstrating the much
higher defect density in the supported CNT segments. By comparing the E33
resonance spectra measured by Raman excitation spectroscopy and
photoluminescence (PL) excitation spectroscopy in the suspended CNT segment, we
observe that the peak energy in the PL excitation spectrum is red-shifted by 40
meV. This shift is associated with the energy difference between the localized
exciton dominating the PL excitation spectrum and the free exciton giving rise
to the Raman excitation spectrum. High-resolution Raman spectra reveal
substrate-induced symmetry breaking, as evidenced by the appearance of
additional peaks in the strongly broadened Raman G band. Laser-induced line
shifts of RBM and G band measured on the suspended CNT segment are both linear
as a function of the laser excitation power. Stokes/anti-Stokes measurements,
however, reveal an increase of the G phonon population while the RBM phonon
population is rather independent of the laser excitation power.Comment: Revised manuscript, 20 pages, 8 figure
Characterisation of Bioglass based foams developed via replication of natural marine sponges
A comparative characterisation of Bioglass based scaffolds for bone tissue engineering applications developed via a replication technique of natural marine sponges as sacrificial template is presented, focusing on their architecture and mechanical properties. The use of these sponges presents several advantages, including the possibility of attaining higher mechanical properties than those scaffolds made by foam replica method (up to 4 MPa) due to a decrease in porosity (68-76%) without affecting the pore interconnectivity (higher than 99%). The obtained pore structure possesses not only pores with a diameter in the range 150-500 mm, necessary to induce bone ingrowth, but also pores in the range of 0-200 mm, which are requested for complete integration of the scaffold and for neovascularisation. In this way, it is possible to combine the main properties that a three-dimensional scaffold should have for bone regeneration: interconnected and high porosity, adequate mechanical properties and bioactivity
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