1,590 research outputs found

    Gradient‐enhanced TROSY described with Cartesian product operators

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    TROSY, Transverse Relaxation Optimized Spectroscopy, was developed more than a decade ago. Since that time, the 15 N‐ 1 H HSQC‐TROSY experiment has become the standard “fingerprint” correlation spectrum for proteins of high molecular weight. In addition, its implementation in protein triple resonance experiments has pushed the boundaries of NMR assignment up to about 100 kDa, making NMR a highly relevant technique in structural biology. TROSY exploits the dipole‐CSA cross‐correlated relaxation properties of the NH system and selects for the narrowest of the HSQC J‐correlation quartet in both dimensions. The original publications and reviews of TROSY use shift operators and/or single transition product operators to describe the TROSY coherence pathways selections. In this review, we offer a familiar Cartesian product operator approach to comprehensively describe all of the events in the modern TROSY pulse sequence such as multiplet selection, gradient coherence selection, gradient quadrature, and sensitivity enhancement. © 2011 Wiley Periodicals, Inc. Concepts Magn Reson Part A 38: 280–288, 2011.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/88024/1/20228_ftp.pd

    Auditory Training of the Deaf

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    In recent years, educators of the deaf have begun to realize the tremendous importance of auditory training in the life of the deaf child. Auditory training for a child with a hearing impairment, involves making the best use of his residual hearing. It involves learning to listen - to use to a maximum the hearing that he possesses in minimum, to get the most from the least, to hear with deaf ears!\u27 The deaf child must learn to take full advantage of the sound clues available to him and his training in school must be well integrated into his total curriculum

    The impact of mergers on relaxed X-ray clusters - III. Effects on compact cool cores

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    (Abridged) We use the simulations presented in Poole et al. 2006 to examine the effects of mergers on compact cool cores in X-ray clusters. We propose a scheme for classifying the morphology of clusters based on their surface brightness and entropy profiles. Three dominant morphologies emerge: two hosting compact cores and central temperatures which are cool (CCC systems) or warm (CWC systems) and one hosting extended cores which are warm (EWC systems). We find that CCC states are disrupted only after direct collisions between cluster cores in head-on collisions or during second pericentric passage in off-axis mergers. By the time they relax, our remnant cores have generally been heated to warm core (CWC or EWC) states but subsequently recover CCC states. The only case resulting in a long-lived EWC state is a slightly off-axis 3:1 merger for which the majority of shock heating occurs during the accretion of a low-entropy stream formed from the disruption of the secondary's core. Compression prevents core temperatures from falling until after relaxation thus explaining the observed population of relaxed CWC systems with no need to invoke AGN feedback. The morphological segregation observed in the L_x-T_x and beta-r_c scaling relations is reflected in our simulations as well. However, none of the cases we have studied produce sufficiently high remnant central entropies to account for the most under-luminous EWC systems observed. Lastly, systems which initially host central metallicity gradients do not yield merger remnants with flat metallicity profiles. Taken together, these results suggest that once formed, compact core systems are remarkably stable against disruption from mergers. It remains to be demonstrated exactly how the sizable observed population of extended core systems was formed.Comment: 19 pages, 8 figures, submitted for publication in MNRA

    XMM-Newton study of the lensing cluster of galaxies CL0024+17

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    We present a detailed gravitational mass measurement based on the XMM-Newton imaging spectroscopy analysis of the lensing cluster of galaxies CL0024+17 at z=0.395. The emission appears approximately symmetric. However, on the scale of r~3.3' some indication of elongation is visible in the northwest-southeast (NW-SE) direction from the hardness ratio map (HRM). Within 3', we measure a global gas temperature of 3.52\pm0.17 keV, metallicity of 0.22\pm0.07, and bolometric luminosity of 2.9\pm0.1 \times 10^{44} h^{-2}_{70} erg/s. We derive a temperature distribution with an isothermal temperature of 3.9 keV to a radius of 1.5' and a temperature gradient in the outskirts (1.3<r<3'). Under the assumption of hydrostatic equilibrium, we measure gravitational mass and gas mass fraction to be M_{200}=2.0\pm0.3 \times 10^{14} h_{70}^{-1} M_{\odot} and f_{\rm gas}=0.20\pm0.03 h^{-3/2}_{70} at r_{200}=1.05 h^{-1}_{70} Mpc using the observed temperature profile. The complex structure in the core region is the key to explaining the discrepancy in gravitational mass determined from XMM-Newton X-ray observations and HST optical lensing measurements.Comment: 16 pages, 12 figures, to appear in A&

    Developmentally appropriate practice in the 21st century

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    Developmentally appropriate practice (DAP) is a set of early childhood curricular recommendations published by the National Association for the Education of Young Children (NAEYC). DAP was introduced in the United States in the late 1980s through Bredekamp’s (1987) seminal work, “Developmentally Appropriate Practice in Early Childhood Programs Serving Children from Birth through Age 8.” Since the initial publication, DAP has been widely accepted as the standard for early childhood educational practice in the United States and in Westernized countries around the world. Whereas proponents of DAP assert its positive influence on children, those more critical of DAP question whether it supports experiences for all young children equally. The aim of this chapter is to (a) describe a developmentally appropriate practice and its theoretical underpinnings, (b) to describe the conceptualization of the child and the role of the adult in DAP, and (c) to synthesize critiques of and recommended changes to DAP

    The physics of galactic winds driven by active galactic nuclei

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    Active galactic nuclei (AGN) drive fast winds in the interstellar medium of their host galaxies. It is commonly assumed that the high ambient densities and intense radiation fields in galactic nuclei imply short cooling times, thus making the outflows momentum-conserving. We show that cooling of high-velocity, shocked winds in AGN is in fact inefficient in a wide range of circumstances, including conditions relevant to ultra-luminous infrared galaxies (ULIRGs), resulting in energy-conserving outflows. We further show that fast energy-conserving outflows can tolerate a large amount of mixing with cooler gas before radiative losses become important. For winds with initial velocity v_in>~10,000 km s^-1, as observed in ultra-violet and X-ray absorption, the shocked wind develops a two-temperature structure. While most of the thermal pressure support is provided by the protons, the cooling processes operate directly only on the electrons. This significantly slows down inverse Compton cooling, while free free cooling is negligible. Slower winds with v_in~1,000 km s^-1, such as may be driven by radiation pressure on dust, can also experience energy-conserving phases but under more restrictive conditions. During the energy-conserving phase, the momentum flux of an outflow is boosted by a factor ~v_in/2v_s by work done by the hot post-shock gas, where v_s is the velocity of the swept-up material. Energy-conserving outflows driven by fast AGN winds (v_in~0.1c) may therefore explain the momentum fluxes Pdot>>L_AGN/c of galaxy-scale outflows recently measured in luminous quasars and ULIRGs. Shocked wind bubbles expanding normal to galactic disks may also explain the large-scale bipolar structures observed in some systems, including around the Galactic Center, and can produce significant radio, X-ray, and gamma-ray emission. [Abridged]Comment: 20 pages, 8 figures. MNRAS, in pres

    Addressing race and racism in early childhood: Challenges and opportunities

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    This chapter draws on developmental intergroup theory, parental ethnic-racial socialization literature, anti-bias curricula, and prejudice intervention studies to address the appropriateness of discussing race and racism in early childhood settings. Existing literature about teacher discussions surrounding race and racism is reviewed, best practices are shared, and the need for more research in this area is highlighted. The construct of parental ethnic-racial socialization is mapped onto early childhood anti-bias classroom practices. The chapter also outlines racial ideologies of teachers, specifically anti-bias and colorblind attitudes, and discusses how these ideologies may manifest in classroom practices surrounding race and racism. Colorblind ideology is problematized and dissected to show that colorblind practices may harm children. Young children’s interpretations of race and racism, in light of children’s cognitive developmental level, are discussed. Additionally, findings from racial prejudice intervention studies are applied to teaching. Early literacy practices surrounding race and racism are outlined with practical suggestions for teachers and teacher educators. Moreover, implications of teacher practices surrounding race and racism for children’s development, professional development, and teacher education are discussed

    Deformations of quantum field theories on spacetimes with Killing vector fields

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    The recent construction and analysis of deformations of quantum field theories by warped convolutions is extended to a class of curved spacetimes. These spacetimes carry a family of wedge-like regions which share the essential causal properties of the Poincare transforms of the Rindler wedge in Minkowski space. In the setting of deformed quantum field theories, they play the role of typical localization regions of quantum fields and observables. As a concrete example of such a procedure, the deformation of the free Dirac field is studied.Comment: 35 pages, 3 figure

    How the Kano model contributes to Kansei engineering in services

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    Recent studies show that products and services hold great appeal if they are attractively designed to elicit emotional feelings from customers. Kansei engineering (KE) has good potential to provide a competitive advantage to those able to read and translate customer affect and emotion in actual product and services. This study introduces an integrative framework of the Kano model and KE, applied to services. The Kano model was used and inserted into KE to exhibit the relationship between service attribute performance and customer emotional response. Essentially, the Kano model categorises service attribute quality into three major groups (must-be [M], one-dimensional [O] and attractive [A]). The findings of a case study that involved 100 tourists who stayed in luxury 4- and 5-star hotels are presented. As a practical matter, this research provides insight on which service attributes deserve more attention with regard to their significant impact on customer emotional needs. Statement of Relevance: Apart from cognitive evaluation, emotions and hedonism play a big role in service encounters. Through a focus on delighting qualities of service attributes, this research enables service providers and managers to establish the extent to which they prioritise their improvement efforts and to always satisfy their customer emotions beyond expectation. Keywords: Kansei engineering, emotional feelings, Kano model, service
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