912 research outputs found
Polarization dOTF: on-sky focal plane wavefront sensing
The differential Optical Transfer Function (dOTF) is a focal plane wavefront
sensing method that uses a diversity in the pupil plane to generate two
different focal plane images. The difference of their Fourier transforms
recovers the complex amplitude of the pupil down to the spatial scale of the
diversity. We produce two simultaneous PSF images with diversity using a
polarizing filter at the edge of the telescope pupil, and a polarization camera
to simultaneously record the two images. Here we present the first on-sky
demonstration of polarization dOTF at the 1.0m South African Astronomical
Observatory telescope in Sutherland, and our attempt to validate it with
simultaneous Shack-Hartmann wavefront sensor images.Comment: 11 pages, 9 figures, Proc. SPIE Vol. 991
Size dependence of the photoinduced magnetism and long-range ordering in Prussian blue analog nanoparticles of rubidium cobalt hexacyanoferrate
Nanoparticles of rubidium cobalt hexacyanoferrate
(RbCo[Fe(CN)]HO) were synthesized using different
concentrations of the polyvinylpyrrolidone (PVP) to produce four different
batches of particles with characteristic diameters ranging from 3 to 13 nm.
Upon illumination with white light at 5 K, the magnetization of these particles
increases. The long-range ferrimagnetic ordering temperatures and the coercive
fields evolve with nanoparticle size. At 2 K, particles with diameters less
than approximately 10 nm provide a Curie-like magnetic signal.Comment: 10 pages, 6 figures in text, expanded text and dat
Circuital Analysis of Cylindrical Structures Applied to the Electromagnetic Resolution of Resonant Cavities
Search for the magnetic field of the O7.5 III star xi Persei
Cyclical wind variability is an ubiquitous but as yet unexplained feature
among OB stars. The O7.5 III(n)((f)) star xi Persei is the brightest
representative of this class on the Northern hemisphere. As its prominent
cyclical wind properties vary on a rotational time scale (2 or 4 days) the star
has been already for a long time a serious magnetic candidate. As the cause of
this enigmatic behavior non-radial pulsations and/or a surface magnetic field
are suggested. We present a preliminary report on our attempts to detect a
magnetic field in this star with high-resolution measurements obtained with the
spectropolarimeter Narval at TBL, France during 2 observing runs of 5 nights in
2006 and 5 nights in 2007. Only upper limits could be obtained, even with the
longest possible exposure times. If the star hosts a magnetic field, its
surface strength should be less than about 300 G. This would still be enough to
disturb the stellar wind significantly. From our new data it seems that the
amplitude of the known non-radial pulsations has changed within less than a
year, which needs further investigation.Comment: 2 pages, 6 figures, contributed poster at IAU Symposium 259 "Cosmic
Magnetic Fields: from Planets, to Stars and Galaxies", Tenerife, Spain,
November 3-7, 200
Evidence of low dose effects of the antidepressant fluoxetine and the fungicide prochloraz on the behavior of the keystone freshwater invertebrate Gammarus pulex
Blue Dots Team Transits Working Group Review
Transiting planet systems offer an unique opportunity to observationally
constrain proposed models of the interiors (radius, composition) and
atmospheres (chemistry, dynamics) of extrasolar planets. The spectacular
successes of ground-based transit surveys (more than 60 transiting systems
known to-date) and the host of multi-wavelength, spectro-photometric follow-up
studies, carried out in particular by HST and Spitzer, have paved the way to
the next generation of transit search projects, which are currently ongoing
(CoRoT, Kepler), or planned. The possibility of detecting and characterizing
transiting Earth-sized planets in the habitable zone of their parent stars
appears tantalizingly close. In this contribution we briefly review the power
of the transit technique for characterization of extrasolar planets, summarize
the state of the art of both ground-based and space-borne transit search
programs, and illustrate how the science of planetary transits fits within the
Blue Dots perspective.Comment: 9 pages, 3 figures, to be published in the proceedings (ASP Conf.
Ser.) of the "Pathways Towards Habitable Planets" conference, held in
Barcelona (14-18 Sep 2009
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
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
Perceptions of French and Creole Among First-Generation Adult Haitian English Language Learners
Context: Due to a unique combination of factors, outdoor athletes in the Southeastern United States are at high risk of lightning deaths and injuries. Lightning detection methods are available to minimize lightning strike victims.
Objective: Becoming aware of the risk factors that predispose athletes to lightning strikes and determining the most reliable detection method against hazardous weather will enable Certified Athletic Trainers to develop protocols that protect athletes from injury.
Data Sources: A comprehensive literature review of Medline and Pubmed using key words: lightning, lightning risk factors, lightning safety, lightning detection, and athletic trainers and lightning was completed.
Data Synthesis: Factors predisposing athletes to lighting death or injury include: time of year, time of day, the athlete’s age, geographical location, physical location, sex, perspiration level, and lack of education and preparedness by athletes and staff. Although handheld lightning detectors have become widely accessible to detect lightning strikes, their performance has not been independently or objectively confirmed. There is evidence that these detectors inaccurately detect strike locations by recording false strikes and not recording actual strikes.
Conclusions: Lightning education and preparation are two factors that can be controlled. Measures need to be taken by Certified Athletic Trainers to ensure the safety of athletes during outdoor athletics. It is critical for athletic trainers and supervising staff members to become fully aware of the risks of lightning strikes in order to most effectively protect everyone under their supervision. Even though lightning detectors have been manufactured in an attempt to minimize death and injuries due to lightning strikes, none of the detectors have been proven to be 100% effective. Educating coaches, athletes, and parents on the risks of lightning and the detection methods available, while implementing an emergency action plan for lightning safety, is crucial to ensure the well being of the student-athlete population
Engage D2.6 Annual combined thematic workshops progress report (series 2)
The preparation, organisation and conclusions from the thematic challenge workshops, two ad hoc technical workshops, a technical session on data and a MET/ENV workshop held in 2019 and 2020 are described. Partly due to Covid-19, two of the 2020 thematic challenge workshops scheduled to take place at the end of 2020 were re-scheduled to January 2021. We also report on the preparation for these two workshops, while the conclusions will be included in the next corresponding deliverable
- …