991 research outputs found
Carryless Arithmetic Mod 10
We investigate what arithmetic would look like if carry digits into other
digit position were ignored, so that 9 + 4 = 3, 5 + 5 = 0, 9 X 4 = 6, 5 X 4 =
0, and so on. For example, the primes are now 21, 23, 25, 27, 29, 41, 43, 45,
47, ... .Comment: 7 pages. To the memory of Martin Gardner (October 21, 1914 -- May 22,
2010). Revised version (with a number of small improvements), July 7 201
Indefinite Morse 2-functions; broken fibrations and generalizations
A Morse 2-function is a generic smooth map from a smooth manifold to a
surface. In the absence of definite folds (in which case we say that the Morse
2-function is indefinite), these are natural generalizations of broken
(Lefschetz) fibrations. We prove existence and uniqueness results for
indefinite Morse 2-functions mapping to arbitrary compact, oriented surfaces.
"Uniqueness" means there is a set of moves which are sufficient to go between
two homotopic indefinite Morse 2-functions while remaining indefinite
throughout. We extend the existence and uniqueness results to indefinite, Morse
2-functions with connected fibers.Comment: 74 pages, 41 figures; further errors corrected, some exposition
added, other exposition improved, following referee's comment
Toric self-dual Einstein metrics as quotients
We use the quaternion Kahler reduction technique to study old and new
self-dual Einstein metrics of negative scalar curvature with at least a
two-dimensional isometry group, and relate the quotient construction to the
hyperbolic eigenfunction Ansatz. We focus in particular on the
(semi-)quaternion Kahler quotients of (semi-)quaternion Kahler hyperboloids,
analysing the completeness and topology, and relating them to the self-dual
Einstein Hermitian metrics of Apostolov-Gauduchon and Bryant.Comment: 30 page
Le rassemblement : rhétorique de l'onirisme appliquée à une création cinématographique
Dans le cadre de la maîtrise en communication de l'UQAM, j'ai décidé de me pencher sur la transposition du rêve au cinéma, et ce, par l'intermédiaire d'un mémoire-création consistant en la rédaction d'un scénario de long-métrage à forte teneur onirique. M'intéressant davantage à la dimension syntaxique que sémantique du rêve, l'approche privilégiée fut celle de la rhétorique où j'ai cherché tout d'abord à identifier les principales figures du rêve et à en approfondir le fonctionnement pour les appliquer par la suite à une création. Composé de trois chapitres, ce document d'accompagnement au scénario de long-métrage Le Rassemblement (dont vous trouverez une copie au volume II de ce mémoire) consiste en un retour sur les différents enjeux à la fois théoriques et créatifs qui sont intervenus lors du processus d'écriture. Le premier chapitre servira à mettre en contexte l'histoire proposée alors que seront exposées les diverses intentions à la fois formelles et thématiques sous-jacentes à l'écriture de ce scénario. Ainsi, il sera possible de constater que cette histoire est née tout d'abord d'une volonté d'expérimentation de l'onirisme au niveau formel à laquelle est venu se greffer par la suite un désir d'exploitation de certaines thématiques. Ensuite, le deuxième chapitre se concentrera plus particulièrement sur la rhétorique de l'onirisme. Ainsi, après avoir analysé à partir des théories freudiennes sur le rêve la composition des principales figures de ce dernier, en l'occurrence, la condensation et le déplacement, nous examinerons leur transposition au cinéma. En ce sens, avant de passer à notre propre travail de transposition, nous analyserons tout d'abord comment la condensation et le déplacement ont pu se retrouver à l'intérieur d'oeuvres cinématographiques oniriques déjà existantes à partir de l'analyse d'un corpus de trois films, soit Lost Highway, Being John Malkovich et Mulholland Drive. Suite à cela, viendra donc l'analyse de notre propre travail de transposition où nous constaterons que l'utilisation de la rhétorique du rêve dans le scénario Le Rassemblement ne s'est pas fait dans la seule optique de l'installation de procédés stylistiques, mais qu'elle est venue influencer directement des aspects importants du récit, tels que l'installation des thématiques et la composition de la structure narrative. Puis, pour terminer, le troisième et dernier chapitre consistera en un retour sur notre démarche d'écriture où nous regarderons l'évolution de l'histoire à travers les principales étapes de ce cheminement qui a mené\ud
à ce scénario de long-métrage intitulé Le Rassemblement. ______________________________________________________________________________ MOTS-CLÉS DE L’AUTEUR : Rhétorique, Onirisme, Cinéma, Scénarisation
GPU enabled real-time optical frequency comb spectroscopy and photonic readout
We describe a GPU-enabled approach for real-time optical frequency comb
spectroscopy in which data is recorded, Fourier transformed, normalized, and
fit at data rates up to 2.2 GB/s. As an initial demonstration we have applied
this approach to rapidly interrogate the motion of an optomechanical
accelerometer through the use of an electro-optic frequency comb. However, we
note that this approach is readily amenable to both self-heterodyne and dual
comb spectrometers for molecular spectroscopy as well as photonic readout where
the approach's agility, speed, and simplicity are expected to enable future
improvements and applications
Oligoclonal bands increase the specificity of MRI criteria to predict multiple sclerosis in children with radiologically isolated syndrome
Radiologically isolated syndrome; Children; Multiple sclerosisSÃndrome radiològicament aïllat; Nens; Esclerosi múltipleSÃndrome radiológicamente aislado; Niños; Esclerosis múltipleBACKGROUND:
Steps towards the development of diagnostic criteria are needed for children with the radiologically isolated syndrome to identify children at risk of clinical demyelination.
OBJECTIVES:
To evaluate the 2005 and 2016 MAGNIMS magnetic resonance imaging criteria for dissemination in space for multiple sclerosis, both alone and with oligoclonal bands in cerebrospinal fluid added, as predictors of a first clinical event consistent with central nervous system demyelination in children with radiologically isolated syndrome.
METHODS:
We analysed an international historical cohort of 61 children with radiologically isolated syndrome (≤18 years), defined using the 2010 magnetic resonance imaging dissemination in space criteria (Ped-RIS) who were followed longitudinally (mean 4.2 ± 4.7 years). All index scans also met the 2017 magnetic resonance imaging dissemination in space criteria.
RESULTS:
Diagnostic indices (95% confidence intervals) for the 2005 dissemination in space criteria, with and without oligoclonal bands, were: sensitivity 66.7% (38.4-88.2%) versus 72.7% (49.8-89.3%); specificity 83.3% (58.6-96.4%) versus 53.9% (37.2-69.9%). For the 2016 MAGNIMS dissemination in space criteria diagnostic indices were: sensitivity 76.5% (50.1-93.2%) versus 100% (84.6-100%); specificity 72.7% (49.8-89.3%) versus 25.6% (13.0-42.1%).
CONCLUSIONS:
Oligoclonal bands increased the specificity of magnetic resonance imaging criteria in children with Ped-RIS. Clinicians should consider testing cerebrospinal fluid to improve diagnostic certainty. There is rationale to include cerebrospinal fluid analysis for biomarkers including oligoclonal bands in planned prospective studies to develop optimal diagnostic criteria for radiologically isolated syndrome in childre
In flight calibration of the ISGRI camera
ISGRI, the IBIS low energy camera (15 keV - 1 MeV) on board INTEGRAL, is the
first large CdTe gamma-ray imager in orbit. We present here an overview of the
ISGRI in-flight calibrations performed during the first months after launch. We
discuss the stability of the camera as well as the CdTe pixels response under
cosmic radiation. The energy calibra tions were done using lead and tungsten
fluorescence lines and the calibration unit. Thermal effects
and charge correction algorithm are discussed, and the resulting energy
resolution is presented. The ISGRI background spatial and spectral
non-uniformity is also described, and some image correction results are
presented
Oral versus intravenous high-dose methylprednisolone for treatment of relapses in patients with multiple sclerosis (COPOUSEP)
International audienceSummaryBackground High doses of intravenous methylprednisolone are recommended to treat relapses in patients with multiple sclerosis, but can be inconvenient and expensive. We aimed to assess whether oral administration of high-dose methylprednisolone was non-inferior to intravenous administration. Methods We did this multicentre, double-blind, randomised, controlled, non-inferiority trial at 13 centres for multiple sclerosis in France. We enrolled patients aged 18–55 years with relapsing-remitting multiple sclerosis who reported a relapse within the previous 15 days that caused an increase of at least one point in one or more scores on the Kurtzke Functional System Scale. With use of a computer-generated randomisation list and in blocks of four, we randomly assigned (1:1) patients to either oral or intravenous methylprednisolone, 1000 mg, once a day for 3 days. Patients, treating physicians and nurses, and data and outcome assessors were all masked to treatment allocation, which was achieved with the use of saline solution and placebo capsules. The primary endpoint was the proportion of patients who had improved by day 28 (decrease of at least one point in most affected score on Kurtzke Functional System Scale), without need for retreatment with corticosteroids, in the per-protocol population. The trial was powered to assess non-inferiority of oral compared with intravenous methylprednisolone with a predetermined non-inferiority margin of 15%. This trial is registered with ClinicalTrials.gov, number NCT00984984. Findings Between Jan 29, 2008, and June 14, 2013, we screened 200 patients and enrolled 199. We randomly assigned 100 patients to oral methylprednisolone and 99 patients to intravenous methylprednisolone with a mean time from relapse onset to treatment of 7·0 days (SD 3·6) and 7·4 days (3·9), respectively. In the per-protocol population, 66 (81%) of 82 patients in the oral group and 72 (80%) of 90 patients in the intravenous group achieved the primary endpoint (absolute treatment difference 0·5%, 90% CI −9·5 to 10·4). Rates of adverse events were similar, but insomnia was more frequently reported in the oral group (77 [77%]) than in the intravenous group (63 [64%]). Interpretation Oral administration of high-dose methylprednisolone for 3 days was not inferior to intravenous administration for improvement of disability scores 1 month after treatment and had a similar safety profile. This finding could have implications for access to treatment, patient comfort, and cost, but indication should always be properly considered by clinicians. Funding French Health Ministry, Ligue Française contre la SEP, Tev
QSO Absorbing Galaxies at z<~1: Deep Imaging and Spectroscopy in the Field of 3C 336
We present very deep WFPC2 images and FOS spectroscopy from the Hubble Space
Telescope (HST) together with numerous supporting ground-based observations of
the field of the quasar 3C 336 (). The observations are designed
to investigate the nature of galaxies producing metal line absorption systems
in the spectrum of the QSO. Along a single line of sight, we find at least 6
metal line absorption systems (of which 3 are newly discovered) ranging in
redshift from 0.317 to 0.892. Through an extensive program of optical and IR
imaging, QSO spectroscopy, and faint galaxy spectroscopy, we have identified 5
of the 6 metal line absorption systems with luminous (L_K > 0.1 L*_K) galaxies.
These have morphologies ranging from very late-type spiral to S0, and exhibit a
wide range of inclination and position angles with respect to the QSO
sightline. The only unidentified absorber, despite our intensive search, is a
damped Lyman system at . Analysis of the absorption
spectrum suggests that the metal abundances ([Fe/H]) in this system are
similar to those in damped systems at , and to the two other damped
systems for which abundances have been determined at . We have found no
examples of intrinsically faint galaxies () at small impact
parameters that might have been missed as absorber candidates in our previous
ground-based imaging and spectroscopic programs on MgII absorbing galaxies.
There are no bright galaxies (L > 0.1 L_K) within 50h^{-1} kpc which do not
produce detectable metal lines (of Mg II 2796, 2803 and/or C IV 1548, 1550) in
the QSO spectrum. All of these results generally support the inferences which
we have previously reached from a larger survey for absorption-selected
galaxies at z\simlt 1.Comment: 32 pages latex (AAS v4.0 style). 8 Postscript figures (including HST
plate) available at ftp://astro.caltech.edu/users/ccs/3c336_figs.ps.gz .
Submitted to Ap
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