3,087 research outputs found
Spin-Orbit Alignment for the Circumbinary Planet Host Kepler-16 A
Kepler-16 is an eccentric low-mass eclipsing binary with a circumbinary transiting planet. Here, we investigate the
angular momentum of the primary star, based on Kepler photometry and Keck spectroscopy. The primary starâs
rotation period is 35.1 ± 1.0 days, and its projected obliquity with respect to the stellar binary orbit is 1°.6 ± 2°.4. Therefore, the three largest sources of angular momentumâthe stellar orbit, the planetary orbit, and the primaryâs rotationâare all closely aligned. This finding supports a formation scenario involving accretion from a single disk. Alternatively, tides may have realigned the stars despite their relatively wide separation (0.2 AU), a hypothesis that is supported by the agreement between the measured rotation period and the âpseudosynchronousâ period of tidal evolution theory. The rotation period, chromospheric activity level, and fractional light variations suggest a main-sequence age of 2â4 Gyr. Evolutionary models of low-mass stars can match the observed masses and radii of the primary and secondary stars to within about 3%
The History of the Mysterious Eclipses of KH 15D: Asiago Observatory, 1967-1982
We are gathering archival observations to determine the photometric history
of the unique and unexplained eclipses of the pre-main-sequence star KH 15D.
Here we present a light curve from 1967-1982, based on photographic plates from
Asiago Observatory. During this time, the system alternated periodically
between bright and faint states, as observed today. However, the bright state
was 0.9 mag brighter than the modern value, and the fractional variation
between bright and faint states (Delta I = 0.7 mag) was smaller than observed
today (3.5 mag). A possible explanation for these findings is that the system
contains a second star that was previously blended with the eclipsing star, but
is now completely obscured.Comment: Accepted to AJ. 24 pages, 10 figures, 2 tables. v2: Phase error
corrected in figures 8 and 1
Lotte Reinigerâs career in animation and her first full-Ââlength animated film, The Adventures of Prince Achmed
Title from PDF of title page, viewed on May 22, 2015Thesis advisor: Burton
DunbarVitaIncludes bibliographic references (pages 66-76)Thesis (M.A.)--Department of Art and Art History, 2014Lotte Reiniger was the woman responsible for making the worldâs first full-Ââlength animated film, Die Geschichte des Prinzen Achmed (The Adventures of Prince Achmed, 1926). Along with her collaborators, she worked on the film for three years during the era of the Weimar Republic in Germany. The Adventures of Prince Achmed was shown in theatres all over the world including Berlin, France, London, New York, and Tokyo, and was always met with many positive reviews. Reinigerâs career was a long and
prominent one, but her work is virtually unknown outside of animation studies. While there is not a lack of materials written on Reiniger and her work, there is still very little assessment of her accomplishments. The purpose of this thesis is to establish the art historical significance of Reinigerâs career, specifically
that of The Adventures of Prince Achmed. This thesis treats Lotte Reiniger and the artists who collaborated
on her films, their animation techniques, and how their films were made. Reviews from The Adventures of Prince Achmedâs earliest showings and Reinigerâs contemporariesâ assessments of her workmake it clear that she was a brilliant artist. I compare The Adventures of Prince Achmed with other animated films being made at the time, and consider the artists
that have been inspired by Reinigerâs work up to the present in order to more fully assess the impact of the film on historically significant forms of film art.College of Arts and SciencesIntroduction -- Animation: definitions and explanations -- Lotte Reiniger's bibliography -- The Weimar Republic in Germany -- The Arabian Nights and the narrative of the Adventures of Prince Achmend -- The making of The Adventures of Prince Achmed -- The Adventures of Prince Achmed's premiere -- Reiniger's contribution to animation -- Conclusionmonographi
The Populations of Comet-Like Bodies in the Solar system
A new classification scheme is introduced for comet-like bodies in the Solar
system. It covers the traditional comets as well as the Centaurs and
Edgeworth-Kuiper belt objects. At low inclinations, close encounters with
planets often result in near-constant perihelion or aphelion distances, or in
perihelion-aphelion interchanges, so the minor bodies can be labelled according
to the planets predominantly controlling them at perihelion and aphelion. For
example, a JN object has a perihelion under the control of Jupiter and aphelion
under the control of Neptune, and so on. This provides 20 dynamically distinct
categories of outer Solar system objects in the Jovian and trans-Jovian
regions. The Tisserand parameter with respect to the planet controlling
perihelion is also often roughly constant under orbital evolution. So, each
category can be further sub-divided according to the Tisserand parameter. The
dynamical evolution of comets, however, is dominated not by the planets nearest
at perihelion or aphelion, but by the more massive Jupiter. The comets are
separated into four categories -- Encke-type, short-period, intermediate and
long-period -- according to aphelion distance. The Tisserand parameter
categories now roughly correspond to the well-known Jupiter-family comets,
transition-types and Halley-types. In this way, the nomenclature for the
Centaurs and Edgeworth-Kuiper belt objects is based on, and consistent with,
that for comets.Comment: MNRAS, in press, 11 pages, 6 figures (1 available as postscript, 5 as
gif). Higher resolution figures available at
http://www-thphys.physics.ox.ac.uk/users/WynEvans/preprints.pd
Complementary and Alternative Medicine Use at a Comprehensive Cancer Center
Background. Complementary and alternative medicine (CAM) use is common among cancer patients, but the majority of CAM studies do not specify the time periods in relation to cancer diagnoses. We sought to define CAM use by cancer patients and investigate factors that might influence changes in CAM use in relation to cancer diagnoses. Methods. We conducted a cross-sectional survey of adults diagnosed with breast, prostate, lung, or colorectal cancer between 2010 and 2012 at the Lineberger Comprehensive Cancer Center. Questionnaires were sent to 1794 patients. Phone calls were made to nonrespondents. Log binomial/Poisson regressions were used to investigate the association between cancer-related changes in CAM use and conversations about CAM use with oncology providers. Results. We received 603 (33.6 %) completed questionnaires. The mean age (SD) was 64 (11) years; 62% were female; 79% were white; and 98% were non-Hispanic. Respondents reported the following cancer types: breast (47%), prostate (27%), colorectal (14%), lung (11%). Eighty-nine percent reported lifetime CAM use. Eighty-five percent reported CAM use during or after initial cancer treatment, with category-specific use as follows: mind-body medicine 39%, dietary supplements 73%, body-based therapies 30%, and energy medicine 49%. During treatment CAM use decreased for all categories except energy medicine. After treatment CAM use returned to pretreatment levels for most CAMs except chiropractic. Initiation of CAM use after cancer diagnosis was positively associated with a patient having a conversation about CAM use with their oncology provider, mainly driven by patient-initiated conversations. Conclusions. Consistent with previous studies, CAM use was common among our study population. Conversations about CAM use with oncology providers appeared to influence cessation of mind-body medicine use after cancer diagnosis
Pushover analysis of reinforced concrete structures applied to blast load using different plastic hinge models
The current work developed a modified pushover method using the Dynamic Load Factor DLF concept to give reasonable results compared to the more complex and time-consuming method (i.e., the non-linear time history method). A charge of 100 kg TNT is assumed to explode at different stand-off distances to cover the three blast design ranges of the (UFC 340-02) Code. The values of (DLF) were checked by applying them to the value of the blast load at the stand-off distances range between (10-70m). The results of the modified pushover method approached that of nonlinear time history with differences not exceeding (11.8%) and (4%) for maximum displacement and shear force, respectively. The DLF was suggested to be constant and equal (2.5) for the (high-pressure) design range and (1) for the (very-low pressure) design range. A formula was proposed for the (low-pressure) design range to simulate the descending values from (2.5) to (1). The prior plastic hinge models proposed by other researchers (Hawraa 2019 and Samer 2020) were used to explore the more realistic structural response to blast loads compared to the standard model of ASCE41-17. Both models of the plastic hinge demonstrated a Collapse Prevention (CP) performance at the (high-pressure) design range. However, the ASCE model indicated that more columns failed in this range. Considering the ASCE 41-17 and proposed approaches, the building performance at the (low-pressure) design range corresponds to the CP and Immediate Occupancy (IO) categories. Some plastic hinges were found when using the proposed plastic hinge model, but the number was nearly identical to that obtained using the ASCE method. The structure did not go beyond the elastic behavior if the proposed plastic hinge model is used in the (very low-pressure) design range. In the same design range, the structure performance lies within the (IO) category concerning the ASCE model. Generally, the suggested plastic hinge approach has been deemed sturdy due to being developed using the blast load and considered more dependable than those of ASCE41-17, which is acceptable for seismic events
Steroids for acute COPD - but for how long?
"Steroids for acute COPD--but for how long? Not only was a shorter course of glucocorticoid therapy as effective as a 14-day regimen, but there was no difference in the time to next exacerbation."Prescribe a 5-day regimen of glucocorticoid therapy for acute chronic obstructive pulmonary disease (COPD) exacerbations; the shorter course of treatment appears to be as effective as a 14-day regimen
Nonlinear interactions with an ultrahigh flux of broadband entangled photons
We experimentally demonstrate sum-frequency generation (SFG) with entangled
photon-pairs, generating as many as 40,000 SFG photons per second, visible even
to the naked eye. The nonclassical nature of the interaction is exhibited by a
linear intensity-dependence of the nonlinear process. The key element in our
scheme is the generation of an ultrahigh flux of entangled photons while
maintaining their nonclassical properties. This is made possible by generating
the down-converted photons as broadband as possible, orders of magnitude wider
than the pump. This approach is readily applicable for other nonlinear
interactions, and may be applicable for various quantum-measurement tasks.Comment: 4 pages, 2 figures, Accepted to Phys. Rev. Let
Political Culture and Gambling Policy: A Cross-National Study
This paper seeks to find relationships between political culture and policy making on gambling in four jurisdictions, including Nevada and California, two adjacent U.S. States, and also in Great Britain and Israel. While the stages of political culture have not advanced to a tightly knit theory from which an array of testable hypotheses can flow, the concept can be helpful in understanding policy developments in gambling across national borders. Though this discussion leans toward the academic style, it offers a practical approach to cultural sensitivity that casino operatives should consider when expanding to divergent populations in new host communities, to avoid policy backlashes that may be detrimental to their gaming financial operations
Fission yeast sec3 bridges the exocyst complex to the actin cytoskeleton.
The exocyst complex tethers post-Golgi secretory vesicles to the plasma membrane prior to docking and fusion. In this study, we identify Sec3, the missing component of the Schizosaccharomyces pombe exocyst complex (SpSec3). SpSec3 shares many properties with its orthologs, and its mutants are rescued by human Sec3/EXOC1. Although involved in exocytosis, SpSec3 does not appear to mark the site of exocyst complex assembly at the plasma membrane. It does, however, mark the sites of actin cytoskeleton recruitment and controls the organization of all three yeast actin structures: the actin cables, endocytic actin patches and actomyosin ring. Specifically, SpSec3 physically interacts with For3 and sec3 mutants have no actin cables as a result of a failure to polarize this nucleating formin. SpSec3 also interacts with actin patch components and sec3 mutants have depolarized actin patches of reduced endocytic capacity. Finally, the constriction and disassembly of the cytokinetic actomyosin ring is compromised in these sec3 mutant cells. We propose that a role of SpSec3 is to spatially couple actin machineries and their independently polarized regulators. As a consequence of its dual role in secretion and actin organization, Sec3 appears as a major co-ordinator of cell morphology in fission yeast.This work was supported
by Cancer Research UK (T. T.)
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