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Observations of the J = 2→1 transitions of <sup>12</sup>C<sup>16</sup>O and <sup>12</sup>C<sup>18</sup>O towards galactic H II regions
Observations are reported of the J = 2→1 transitions of CO and 12C18O at 230 and 219 GHz respectively from a number of galactic sources. A map of the central 1/2° × 1/2° of the Orion A molecular cloud is presented. The spectra are interpreted to derive molecular densities and abundance ratios in the molecular clouds observed
NLO prescription for unintegrated parton distributions
We show how parton distributions unintegrated over the parton transverse
momentum, k_t, may be generated, at NLO accuracy, from the known integrated
(DGLAP-evolved) parton densities determined from global data analyses. A few
numerical examples are given, which demonstrate that sufficient accuracy is
obtained by keeping only the LO splitting functions together with the NLO
integrated parton densities. However, it is important to keep the precise
kinematics of the process, by taking the scale to be the virtuality rather than
the transverse momentum, in order to be consistent with the calculation of the
NLO splitting functions.Comment: 20 pages, 8 figures. v2: version to appear in Eur. Phys. J.
Dark Matter and Baryon Fraction at the Virial Radius in Abell 2256
We combine ASCA and ROSAT X-ray data to constrain the radial dark matter
distribution in the primary cluster of A2256, free from the isothermality
assumption. Both instruments indicate that the temperature declines with
radius. The region including the central galaxy has a multicomponent spectrum,
which results in a wide range of allowed central temperatures. We find that the
secondary subcluster has a temperature and luminosity typical of a rich
cluster; however, the ASCA temperature map shows no signs of an advanced
merger. It is therefore assumed that the primary cluster is in hydrostatic
equilibrium. The data then require dark matter density profiles steeper than
rho ~ r^-2.5 in its outer part. Acceptable models have a total mass within
r=1.5 Mpc (the virial radius) of 6.0+-1.5 10^14 Msun at the 90% confidence,
about 1.6 times smaller than the mass derived assuming isothermality. Near the
center, dark matter profiles with and without central cusps are consistent with
the data. Total mass inside the X-ray core (r=0.26 Mpc) is 1.28+-0.08 10^14
Msun, which exceeds the isothermal value by a factor of 1.4. Although the
confidence intervals above may be underestimates since they do not include
possible asymmetry and departures from hydrostatic equilibrium, the behavior of
the mass distribution, if applicable to other clusters, can bring into better
agreement X-ray and lensing mass estimates, but aggravate the ``baryon
catastrophe''. The observed considerable increase in the gas content with
radius, not anticipated by simulations, may imply that a significant fraction
of thermal gas energy comes from sources other than gravity and merger shocks.Comment: Added dynamic argument against advanced merger. Latex, 10 pages, 3
figures; uses emulateapj.sty. ApJ in pres
Report of committee studying failure reporting in the SAGE and experimental subsectors
Includes: introduction; present failure reporting methods; reports proposed; analysis of status and failure reports; plan of action; conclusion; appendices; and references.Recommendations of the committee studying failure reporting, appointed at a meeting on 14 June 1955
New parton distributions in fixed flavour factorization scheme from recent deep-inelastic-scattering data
We present our QCD analysis of the proton structure function
to determine the parton distributions at the next-to-leading order (NLO). The
heavy quark contributions to , with = , have been
included in the framework of the `fixed flavour number scheme' (FFNS). The
results obtained in the FFNS are compared with available results such as the
general-mass variable-flavour-number scheme (GM-VFNS) and other prescriptions
used in global fits of PDFs. In the present QCD analysis, we use a wide range
of the inclusive neutral-current deep-inelastic-scattering (NC DIS) data,
including the most recent data for charm , bottom , longitudinal
structure functions and also the reduced DIS cross sections
from HERA experiments. The most recent HERMES data for
proton and deuteron structure functions are also added. We take into account
ZEUS neutral current DIS inclusive jet cross section data from HERA
together with the recent Tevatron Run-II inclusive jet cross section data from
CDF and D{\O}. The impact of these recent DIS data on the PDFs extracted from
the global fits are studied. We present two families of PDFs, {\tt KKT12} and
{\tt KKT12C}, without and with HERA `combined' data sets on DIS. We
find these are in good agreement with the available theoretical models.Comment: 23 pages, 26 figures and 4 tables. V3: Only few comments and
references added in the replaced version, results unchanged. Code can be
found at http://particles.ipm.ir/links/QCD.ht
The thermal ecology of some Colias butterfly larvae
The thermal ecology of Colias butterfly larvae has been studied, using simple modifications of previous thermistor implantation technology. Like their adults, these larvae rely on a repertoire of thermoregulatory behavior to control body temperature in relation to external heat sources and sinks. They neither heat nor cool by metabolic means. They display narrow, well-marked body temperature ranges for their major activity, feeding. These are 10–15 °C lower than the maximum activity temperatures of the adults. Also in contrast to the adults, the locations of the larval activity maxima differ by several degrees C between the taxa studied. In each taxon studied the rate of feeding reaches a maximum in a body temperature range corresponding roughly to the temperature range maximizing the occurrence of feeding. The overall larval growth rate is maximized under constant temperature regimes corresponding to the maximum feeding range. A qualitative model for larval activity in the field in relation to daily temperature changes is constructed and apparently supported in its essentials. These results are discussed in relation to other aspects of larval ecology, notably predator pressure, and some speculation on their meaning for larval metabolic organization is raised.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47110/1/359_2004_Article_BF00694570.pd
Genomic Organization, Splice Variants and Expression of CGMl, a CD66-related Member of the Carcinoembryonic Antigen Gene Family
The tumor marker carcinoembryonic antigen (CEA) belongs to a family of proteins which are composed of one immunogiobulin variable domain and a varying number of immunoglobulin constant-like domains. Most of the membrane-bound members, which are anchored either by a glycosylphosphatidylinositol moiety or a transmembrane domain, have been shown to convey cell adhesion in vitro. Here we describe two splice variants of CGMI. a transmembrane member of the CEA family without immunoglobulin constant.like domains. CGM1a and CGM1c contain cytopiasmic domains of 71 and 31 amino acids, respectively, The cytoplasmic region of CGM1a is encoded by four exons (Cyt1-Cyt4). Differential splicing of the Cyt1 exon (53 bp)..
A view through a window: Social relations, material objects and locality
In this article the authors ask what it would mean to think sociologically about the window as a specific material and symbolic object. Drawing on qualitative analysis of a series of comparative interviews with residents in three different streets in a diverse local area of Glasgow, they explore what the use and experience of windows tells us about their respondents’ very different relationships to the places where they live. On the one hand, the window, as a material feature of the home, helps us grasp the lived reality of class inequality and how such inequality shapes people’s day-to-day experience. On the other hand, windows are symbolically charged objects, existing at the border of the domestic and public world. For this reason, they feature in important ways in local debates over the appearance, ownership and conservation of the built environment. The article explores these struggles, and shows what they reveal about the construction of belonging in the neighbourhood, a process which is both classed and racialised at one and the same time.ESR
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