7,009 research outputs found

    The genealogy of judgement: towards a deep history of academic freedom

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    The classical conception of academic freedom associated with Wilhelm von Humboldt and the rise of the modern university has a quite specific cultural foundation that centres on the controversial mental faculty of 'judgement'. This article traces the roots of 'judgement' back to the Protestant Reformation, through its heyday as the signature feature of German idealism, and to its gradual loss of salience as both a philosophical and a psychological concept. This trajectory has been accompanied by a general shrinking in the scope of academic freedom from the promulgation of world-views to the offering of expert opinion

    A Walking Silicon Robot

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    The goal of this project was to design and implement a MEMS process for the creation of a walking silicon robot using the equipment available at RIT. An attempt was carried out to create a mobility system based on the thermal expansion of polyimide joints as demonstrated by Ebefors. The designed process was successfully implemented through the oxidation of the joint surfaces. Issues with the Al resistor and polyimide lithography prevented the successful completion of the rest of the process

    A 193 nm Deep-UV Lithography System Using a Line-Narrowed ArF Excimer Laser

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    A small field refractive projection system for operation at the 193.3 nm wavelength of a spectrally narrowed ArF excimer laser is being constructed. The 1 mm field, 20X system operates with a variable objective lens numerical aperture from 0.30 to 0.60, variable partial coherence, and control over illumination fill and mask tilt. A 30 W maximum power ArF excimer laser has been spectrally line-narrowed through incorporation of tilted Fabry-Perot etalons into the laser cavity, allowing linewidths on the order of7 cm\u27 (26 pm) with one etalon and 0.5 cm1 (2pm) with two etalons. This work reports laser line narrowing and lens performance results. Simulations of aerial image intensity distributions from lens aberration data will be presented for 0.25 and 0.20 micron geometry

    Comparison of Scalar and Vector Diffraction Modelling for Deep-UV Lithography

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    As deep-UV projection system complexity increases to pursue 0.25 micron resolution, the adequacy of diffraction theory using scalar models is of concern. Approximations that are suitable for low NA reduction systems do not hold true for higher NAs. Furthermore, scalar models treat all illumination as polarized perpendicular to the plane of incidence. Feature interaction effects from the polarized radiation of an excimer laser both in a projection system and within a photoresist film cannot be accounted for. Vector diffraction theory has been utilized more appropriately for modelling in these situations, but deviations of scalar predictions from those made with vector models do not warrant abandonment. This paper will describe investigations into scalar and vector diffraction modelling for 248 nm lithography. An experimental design approach was used to study the effects and interactions of coherence, polarization, and numerical aperture on a resist feature response. An exposure latitude response to achieve 1 0% linewidth control with +1- 0.3 micron of defocus was utilized. Both vector and scalar diffraction models were used to simulate process runs. Experimental comparisons were made using a variable NA, variable coherence deep-UV projection system, adapted for control of polarization at the aperture of the mask. Exposure latitude response surfaces are presented, along with details on isolated process runs

    Bostonia. Volume 11

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    Founded in 1900, Bostonia magazine is Boston University's main alumni publication, which covers alumni and student life, as well as university activities, events, and programs

    Nuclear Theory and Science of the Facility for Rare Isotope Beams

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    The Facility for Rare Isotope Beams (FRIB) will be a world-leading laboratory for the study of nuclear structure, reactions and astrophysics. Experiments with intense beams of rare isotopes produced at FRIB will guide us toward a comprehensive description of nuclei, elucidate the origin of the elements in the cosmos, help provide an understanding of matter in neutron stars, and establish the scientific foundation for innovative applications of nuclear science to society. FRIB will be essential for gaining access to key regions of the nuclear chart, where the measured nuclear properties will challenge established concepts, and highlight shortcomings and needed modifications to current theory. Conversely, nuclear theory will play a critical role in providing the intellectual framework for the science at FRIB, and will provide invaluable guidance to FRIB's experimental programs. This article overviews the broad scope of the FRIB theory effort, which reaches beyond the traditional fields of nuclear structure and reactions, and nuclear astrophysics, to explore exciting interdisciplinary boundaries with other areas. \keywords{Nuclear Structure and Reactions. Nuclear Astrophysics. Fundamental Interactions. High Performance Computing. Rare Isotopes. Radioactive Beams.Comment: 20 pages, 7 figure

    Vasopressin/serotonin interactions in the anterior hypothalamus control aggressive behavior in golden hamsters

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    Studies in several species of rodents show that arginine vasopressin (AVP) acting through a V1A receptor facilitates offensive aggression, i.e., the initiation of attacks and bites, whereas serotonin (5-HT) acting through a 5-HT1B receptor inhibits aggressive responding. One area of the CNS that seems critical for the organization of aggressive behavior is the basolateral hypothalamus, particularly the anterior hypothalamic region. The present studies examine the neuroanatomical and neurochemical interaction between AVP and 5-HT at the level of the anterior hypothalamus (AH) in the control of offensive aggression in Syrian golden hamsters. First, specific V1A and 5-HT1B binding sites in the AH are shown by in vitro receptor autoradiography. The binding for each neurotransmitter colocalizes with a dense field of immunoreactive AVP and 5-HT fibers and putative terminals. Putative 5-HT synapses on AVP neurons in the area of the AH are identified by double-staining immunocytochemistry and laser scanning confocal microscopy. These morphological data predispose a functional interaction between AVP and 5-HT at the level of the AH. When tested for offensive aggression in a resident/intruder paradigm, resident hamsters treated with fluoxetine, a selective 5-HT reuptake inhibitor, have significantly longer latencies to bite and bite fewer times than vehicle-treated controls. Conversely, AVP microinjections into the AH significantly shorten the latency to bite and increase biting attacks. The action of microinjected AVP to increase offensive aggression is blocked by the pretreatment of hamsters with fluoxetine. These data suggest that 5-HT inhibits fighting, in part, by antagonizing the aggression-promoting action of the AVP system

    APS Neutrino Study: Report of the Neutrino Astrophysics and Cosmology Working Group

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    In 2002, Ray Davis and Masatoshi Koshiba were awarded the Nobel Prize in Physics ``for pioneering contributions to astrophysics, in particular for the detection of cosmic neutrinos.'' However, while astronomy has undergone a revolution in understanding by synthesizing data taken at many wavelengths, the universe has only barely been glimpsed in neutrinos, just the Sun and the nearby SN 1987A. An entire universe awaits, and since neutrinos can probe astrophysical objects at densities, energies, and distances that are otherwise inaccessible, the results are expected to be particularly exciting. Similarly, the revolution in quantitative cosmology has heightened the need for very precise tests that depend on the effects of neutrinos, and prominent among them is the search for the effects of neutrino mass, since neutrinos are a small but known component of the dark matter. In this report, we highlight some of the key opportunties for progress in neutrino astrophysics and cosmology, and the implications for other areas of physics

    Elastic constants of beta-eucryptite: A density functional theory study

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    The five independent elastic constants of hexagonal β\beta-eucryptite have been determined using density functional theory (DFT) total energy calculations. The calculated values agree well, to within 15%, with the experimental data. Using the calculated elastic constants, the linear compressibility of β\beta-eucryptite parallel to the c-axis, χc\chi_c, and perpendicular to it, χa\chi_a, have been evaluated. These values are in close agreement to those obtained from experimentally known elastic constants, but are in contradiction to the direct measurements based on a three-terminal technique. The calculated compressibility parallel to the c-axis was found to positive as opposed to the negative value obtained by direct measurements. We have demonstrated that χc\chi_c must be positive and discussed the implications of a positive χc\chi_c in the context of explaining the negative bulk thermal expansion of β\beta-eucryptite.Comment: 3 eps figures, submitted for publicatio

    The measurement of low pay in the UK labour force survey

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    Consideration of the National Minimum Wage requires estimates of the distribution of hourly pay. The UK Labour Force Survey (LFS) is a key source of such estimates. The approach most frequently adopted by researchers has been to measure hourly earnings from several questions on pay and hours. The Office for National Statistics is now applying a new approach, based on an alternative more direct measurement introduced in March 1999. These two measures do not produce identical values and this paper investigates sources of discrepancies and concludes that the new variable is more accurate. The difficulty with using the new variable is that it is only available on a subset of respondents. An approach is developed in which missing values of the new variable are replaced by imputed values. The assumptions underlying this imputation approach and results of applying it to LFS data are presented. The relation to weighting approaches is also discussed
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