187,135 research outputs found

    The BOSS Emission-Line Lens Survey. III. : Strong Lensing of Lyα\alpha Emitters by Individual Galaxies

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    We introduce the Baryon Oscillation Spectroscopic Survey (BOSS) Emission-Line Lens Survey (BELLS) for GALaxy-Lyα\alpha EmitteR sYstems (BELLS GALLERY) Survey, which is a Hubble Space Telescope program to image a sample of galaxy-scale strong gravitational lens candidate systems with high-redshift Lyα\alpha emitters (LAEs) as the background sources. The goal of the BELLS GALLERY Survey is to illuminate dark substructures in galaxy-scale halos by exploiting the small-scale clumpiness of rest-frame far-UV emission in lensed LAEs, and to thereby constrain the slope and normalization of the substructure-mass function. In this paper, we describe in detail the spectroscopic strong-lens selection technique, which is based on methods adopted in the previous Sloan Lens ACS (SLACS) Survey, BELLS, and SLACS for the Masses Survey. We present the BELLS GALLERY sample of the 21 highest-quality galaxy--LAE candidates selected from 1.4×106\approx 1.4 \times 10^6 galaxy spectra in the BOSS of the Sloan Digital Sky Survey III. These systems consist of massive galaxies at redshifts of approximately 0.5 strongly lensing LAEs at redshifts from 2--3. The compact nature of LAEs makes them an ideal probe of dark substructures, with a substructure-mass sensitivity that is unprecedented in other optical strong-lens samples. The magnification effect from lensing will also reveal the structure of LAEs below 100 pc scales, providing a detailed look at the sites of the most concentrated unobscured star formation in the universe. The source code used for candidate selection is available for download as a part of this release.Comment: 14 pages, 5 figures, accepted for publication in the ApJ (ApJ, 824, 86). Minor edits to match the ApJ published versio

    The assessment of hemineglect syndrome with cancellation tasks. A comparison between the bells test and the Apples test

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    Unilateral spatial neglect (USN) is a frequent consequence of acquired brain injury, especially following right hemisphere damage. Traditionally, unilateral spatial neglect is assessed with cancellation tests such as the Bells test. Recently, a new cancellation test, the Apples test, has been proposed. The present study aims at comparing the accuracy of these two tests in detecting hemispatial neglect, on a sample of 56 right hemisphere stroke patients with a diagnosis of USN. In order to evaluate the agreement between the Apples and Bells tests, Cohen's kappa and McNemar's test were used to assess differences between the two methods of evaluation. Poor agreement and statistically significant differences emerged between the Apples and Bells tests. Overall, the Apples test was significantly more sensitive than the Bells test in detecting USN. Based on these results, the use of the Apples test for peripersonal neglect assessment is therefore highly recommende

    Partial frequencies and Chladni’s law in church bells

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    The rim partials of a church bell (those with an antinode at the soundbow) generate the strike pitch or perceived note of the bell. The spacing in frequency of the higher rim partials has an important effect on the tonal quality of the bell. Investigations into the partial frequencies of 2752 bells, both bronze and steel, of a wide variety of dates, founders and sizes, show a simple and unexpected relationship between the frequencies of the rim partials. This relationship explains why attempts to tune the higher rim partials independently have failed. A modified version of Chladni’s law provides insight into the musical relationship of the partials, and predicts the partials of individual bells well, but fails to give a simple model of the spacing between the partials seen in bells with different profiles

    Glasbury man made Clyro bells

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    [From Introduction] There must have been great excitement in Clyro in 1708. The existing four bells in St Michael's Church were recast by Henry Williams, the bell founder from Glasbury, into a ring of five bells. The work was apparently paid for by the owners of two of the great houses in the parish: Cabalva and Lloyney. Little is known of the four bells that existed in Clyro before Williams began his work, although they appear to have been larger than the five bells cast from their metal. The four bells swung side by side in a wooden frame in the tower of the church. This frame was altered in 1708 to accommodate bells of smaller dimensions and a fifth bell pit was added at right angles to the others.Colin Lewis was Professor of Geography at Rhodes University, Grahamstown, South Africa from 1989 until his retirement at the end of 2007. In 1990, with the strong support of the incumbent Vice-Chancellor, Dr Derek Henderson, he instigated the Certificate in Change Ringing (Church Bell Ringing) in the Rhodes University Department of Music and Musicology - the first such course to be offered in Africa. Since that date he has lectured in the basic theory, and taught the practice of change ringing. He is the Ringing Master of the Cathedral of St Michael and St George, Grahamstown, South Africa

    Manufacture of bells

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    Bakalářská práce s názvem „Výroba zvonů” obsahuje základní informace o historickém vývoji zvonů, akustických vlastnostech zvonů a jednotlivých procesech provázejících jejich výrobu. V práci jsou podrobně popsány jednotlivé fáze výroby a zařízení, které jsou k jejich vykonání nezbytná. V textu je také pojednáno o materiálech, které jsou pro výrobu zvonů používány. Nejvíce je v této části pojednáváno o zvonovině, neboť se jedná o nejlepší a nejpoužívanější materiál pro tyto účely.The bachelor thesis titled „Manufacture of bells” contains basic information about the historical development of bells, acoustic characteristics of the bells and particular processes accompanying their production. There are in detail particular phases of production and necessary equipment described in this work. The text also deals with the materials that are used for bells manufacturing. The analysis of the bell metal is the most discussed issue in this part, since it is the best and most widely used material for these purposes.
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