Higher Order and Secondary Hochschild Cohomology

In this note we give a generalization for the higher order Hochschild cohomology and show that the secondary Hochschild cohomology is a particular case of this new construction

Measured electron contribution to Shuttle plasma environment: Abbreviated update

The differential energy spectra of electrons between 1 and 100 eV were measured by an electron spectrometer flown on an early shuttle. This energy range was scanned in 64 incremental steps with a resolution of 7%. The most striking feature that was observed throughout these spectra was a relatively flat distribution of the higher energy electrons out to 100 eV. This is in contrast to normal ambient spectra which consistently show a rapid decline in quantitative flux beyond 50 to 55 eV. The lower energy (1 to 2 eV) end of these spectra showed steep thermal trails comparable to normal ambient spectral structure. In general, daytime fluxes were significantly higher than those obtained during nighttime measurements. Quantitative flux excursions which may possibly be associated with thruster firing were frequently observed. Spectral structure suggestive of the N2 vibrational excitation energy loss mechanism was also seen in the data from some measurement periods. Examples of these spectra are shown and possible correlations are discussed

Our Heritage, the Soil

PDF pages: 2

High-contrast imaging of Sirius~A with VLT/SPHERE: Looking for giant planets down to one astronomical unit

Sirius has always attracted a lot of scientific interest, especially after the discovery of a companion white dwarf at the end of the 19th century. Very early on, the existence of a potential third body was put forward to explain some of the observed properties of the system. We present new coronagraphic observations obtained with VLT/SPHERE that explore, for the very first time, the innermost regions of the system down to 0.2" (0.5 AU) from Sirius A. Our observations cover the near-infrared from 0.95 to 2.3 $\mu$m and they offer the best on-sky contrast ever reached at these angular separations. After detailing the steps of our SPHERE/IRDIFS data analysis, we present a robust method to derive detection limits for multi-spectral data from high-contrast imagers and spectrographs. In terms of raw performance, we report contrasts of 14.3 mag at 0.2", ~16.3 mag in the 0.4-1.0" range and down to 19 mag at 3.7". In physical units, our observations are sensitive to giant planets down to 11 $M_{Jup}$ at 0.5 AU, 6-7 $M_{Jup}$ in the 1-2 AU range and ~4 $M_{Jup}$ at 10 AU. Despite the exceptional sensitivity of our observations, we do not report the detection of additional companions around Sirius A. Using a Monte Carlo orbital analysis, we show that we can reject, with about 50% probability, the existence of an 8 $M_{Jup}$ planet orbiting at 1 AU. In addition to the results presented in the paper, we provide our SPHERE/IFS data reduction pipeline at http://people.lam.fr/vigan.arthur/ under the MIT license.Comment: 16 pages, 10 figures, accepted for publication in MNRA

Better Pastures for Ohio Livestock

PDF pages: 3

Students use of laptops in large lecture classes: distraction, partial attention or productive use

http://editlib.org/p/34929ED-Media. World Conference on Educational Multimedia, Hypermedia & Telecommunications. Proceedings, 2010, v. 2010 n. 1, p. 2136-2141An increasing number of students are bringing personal laptops to their classes and are using laptops during lectures. This increasing use of personal mobile devices has been described as a shift from e-learning (electronic learning) to m-learning (mobile learning). However, a large debate on the appropriateness of the use of laptops in class has emerged. Many teachers describe that students use laptops for surfing the net, emailing, downloading software and using chat forums during class rather than paying attention to the lecture. This paper reports on the use of laptops in a large lecture class of 650+ students and describes a pilot project that introduced an innovative system that was designed to both focus the attention of students during the class and engage them with the course material outside of class. Educational implications and next steps will be discussed.postprin

Method of and means for testing a tape record/playback system

A tape record/playback system was tested by first deriving an analog test signal and a band-limited digital reference signal from a pseudo-noise sequence generator driven by a clock signal. It recorded the signals on respective tracks of the system during operation in a record mode. During the playback mode of operation of the system, a delayed analog reference signal without time base variations was reconstructed from the played back reference signal. It was compared with the played back test signal in order to obtain an error signal that was a measure of the performance of the system

Hydrogen thermal conductivity at temperatures from 2000 to 4000 deg F Final report

Hydrogen thermal conductivity at temperatures from 2000 to 4600 deg

Approaches to teaching and technology use among international award winning university teachers

There is wide-spread acknowledgement of the benefits of well thought out online learning opportunities that provide students with active learning environments that extend the classroom space. This paper reports on the approaches to teaching in general, and in particular approaches to the use of technology, by award winning university faculty in Canada, Australia and Hong Kong. Findings indicate that the majority of these award winning teachers adopted an approach to teaching that was student centered and focused on changing the students’ conceptions of the material being studied, rather than an approach that was information focused. While technology as a tool to provide information resources was a part of their repertoire, their use of technology extended beyond content delivery to provide activities and resources for active learning. Examples of how they incorporated technology for active learning will be provided.postprintThe World Conference on Educational Multimedia, Hypermedia & Telecommunications (EDMEDIA 2010), Toronto, Canada, 28 June-2 July 2010. In Proceedings of EDMEDIA, 2010, n. 1, p. 2565-257

Compact steep-spectrum sources from the S4 sample

We present the results of 5-GHz observations with the VLA A-array of a sample of candidate Compact Steep Spectrum sources (CSSs) selected from the S4 survey. We also estimate the symmetry parameters of high-luminosity CSSs selected from different samples of radio sources, and compare these with the larger sources of similar luminosity to understand their evolution and the consistency of the CSSs with the unified scheme for radio galaxies and quasars. The majority of CSSs are likely to be young sources advancing outwards through a dense asymmetric environment. The radio properties of CSSs are found to be consistent with the unified scheme, in which the axes of the quasars are observed close to the line of sight, while radio galaxies are observed close to the plane of the sky.Comment: accepted for publication in mnras; 8 pages, figure 1 with 21 images, and two additional figures; 2 table