12,259 research outputs found
Optical off-nuclear spectra of quasar hosts and radio galaxies
We present optical (~3200A to ~9000A) off-nuclear spectra of 26 powerful
active galaxies in the redshift range 0.1 < z < 0.3, obtained with the Mayall
and William Herschel 4-meter class telescopes. The sample consists of
radio-quiet quasars, radio-loud quasars (all with -23 > M_V > -26) and radio
galaxies of Fanaroff & Riley Type II (with extended radio luminosities and
spectral indices comparable to those of the radio-loud quasars). The spectra
were all taken approximately 5 arcseconds off-nucleus, with offsets carefully
selected so as to maximise the amount of galaxy light falling into the slit,
whilst simultaneously minimising the amount of scattered nuclear light. The
majority of the resulting spectra appear to be dominated by the integrated
stellar continuum of the underlying galaxies rather than by light from the
non-stellar processes occurring in the active nuclei, and in many cases a 4000A
break feature can be identified. The individual spectra are described in
detail, and the importance of the various spectral components is discussed.
Stellar population synthesis modelling of the spectra will follow in a
subsequent paper (Nolan et al. 2000).Comment: 23 pages, LaTeX, uses MNRAS style file, incorporates 71 postscript
figures, to be published in MNRAS. Contact author: [email protected]
Enantioselective synthesis and application to the allylic imidate rearrangement of amine-coordinated palladacycle catalysts of cobalt sandwich complexes
The reaction of (η5-(N,N-dimethylaminomethyl)cyclopentadien-yl)(η4-tetraphenylcyclobutadiene)cobalt with sodium tetrachloropalladate and (R)-N-acetylphenylalanine gave planar chiral palladacycle di-μ-chloridebis[(η5-(Sp)-2-(N,N-dimethylaminomethyl)cyclopentadienyl,1-C,3′-N)(η4-tetraphenylcyclobutadiene)cobalt]dipalladium [(Sp)-Me2-CAP-Cl] in 92 % ee and 64 % yield. Enantiopurity (>98 % ee) was achieved by purification of the monomeric (R)-proline adducts and conversion back to the chloride dimer. Treatment with AgOAc gave (Sp)-Me2-CAP-OAc which was applied to asymmetric transcyclopalladation (up to 78 % ee). The (R)-N-acetylphenylalanine mediated palladation methodology was applicable also to the corresponding N,N-diethyl (82 % ee, 39 % yield) and pyrrolidinyl (>98 % ee, 43 % yield) cobalt sandwich complexes. A combination of 5 mol % of the latter [(Sp)-Pyrr-CAP-Cl] and AgNO3 (3.8 equiv) is a catalyst for the allylic imidate rearrangement of an (E)-N-aryltrifluoroacetimidate (up to 83 % ee), and this catalyst system is also applicable to the rearrangement of a range of (E)-trichloroacetimidates (up to 99 % ee). This asymmetric efficiency combined with the simplicity of catalyst synthesis provides accessible solutions to the generation of non-racemic allylic amine derivatives
Priority Information Needs for Band-tailed Pigeons, Zenaida Doves, White-tipped Doves and Scaly-naped Pigeons
Table of Contents
Executive Summary............................i
Introduction............................1
Status of band-tailed pigeons, Zenaida doves, white-tipped doves and scaly-naped pigeons............................2
Priority Information Needs............................7
Priority 1. Reliable demographics of band-tailed pigeons............................8
Priority 2. Association of food availability with abundance and distribution of band-tailed pigeons............................9
Priority 3. Status assessment of white-tipped doves in south Texas to determine distribution, population abundance and biology............................10
Priority 4. Population and harvest data collected annually for Zenaida doves and scaly-naped pigeons............................11
Priority 5. Adaptive harvest strategy for Zenaida doves and scaly-naped pigeons............................12
Measuring Success............................13
Literature Cited............................14
Appendix A: 2010 Strategy Development Participants............................16
Figure 1. Distribution of Pacific Coast and Interior band-tailed pigeons in North America............................2
Figure 2. Abundance indices for the Pacific Coast and Interior populations of band-tailed pigeons based on results from the North American Breeding Bird Survey and the Mineral Site Survey............................3
Figure 3. Distribution of white-tipped doves in North and Central America............................4
Figure 4. Trend in estimated white-tipped doves harvested per hunter and per hunter-day during the September 4-day special white-winged dove season in the Lower Rio Grande Valley of Texas, 1986–2009............................5
Figure 5. Estimated density of scaly-naped pigeons on Puerto Rico in 1986 –2010............................6
Figure 6. Estimated density of Zenaida doves on Puerto Rico in 1986 –2010............................
The idea of moral panic – ten dimensions of dispute
This paper explores the open and contested concept of moral panic over its 40-year history, exploring the contributions made by the concept’s key originators, as well as contemporary researchers. While most moral panic researchers are critical, humanist, interpretivist, interventionist and qualitative, this paper highlights ten areas of productive dispute within and around the meaning of moral panic theory’s ‘common sense’. Such diversity of interpretation creates multiple possibilities for convergent and divergent theorization and research within a supposedly singular conceptual framework. This lack of closure and consequent diversity of political standpoints, intellectual perspectives and fields of empirical focus, rather than representing the weakness of the concept of moral panic, reflects and contributes to its successful diffusion, escalation and innovation
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