3,645 research outputs found
Contact-allergy time
The most commonly used techniques for the in vivo evaluation of the cellular
immune response include intracutaneous testing with microbial recall antigens
or sensitization with neoantigens. The reliability of these tests for the individual
patient usually is low due to the lack of standardization and quantification.
Moreover only the efferent branch of the immune response can be judged.
The dinitrochlorobenzene-contact allergy time (DNCB-CAT) is a quantitative
approach for the assessment of the cellular immune response. 2% DNCBointment
is applied on the upper arm in a 1 cm2 area. On the following days
patch-testing with 0.05% DNCB-ointment is done on the homolateral forearm
in alternating localizations till an allergic contact dermatitis reaction appears.
As assessed in patients with malignant melanoma (MM, n=\\5) and with
lymphoproliferative disorders (LD, η = 25), the DNCB-CAT correlates with
the age of the patients and can be expressed by a formula given by the age
(years) χ factor (MM = 0.16; LD = 0.17) + constant figure (MM = 5.5;
LD = 4.3). There was no significant difference between the two groups or subgroups
investigated.
By DNCB-CAT quantitative analysis of the cellular immune response in
vivo is possible. It is an appropriate model for further investigations of the
cellular immunity under different clinical, histological, prognostic, and therapeutic
aspects
From Troubled Ground to Common Ground : The Locust Grove African- American Cemetery Restoration Project: A Case Study of Service-Learning and Community History
This article chronicles a movement to restore Shippensburg, Pennsylvania\u27s Locust Grove Cemetery, a historic African-American burial ground. The cemetery faced persistent troubles exacerbated by changing demographics in the surrounding neighborhood, its caretakers\u27 limited resources, and the community\u27s history of racial discrimination. Beginning in 2003, Shippensburg University applied history students assisted with research, grant writing, and interpretative materials. By 2005, a community coalition formed that built on the students\u27 efforts, ultimately mobilizing the resources needed to finish the restoration. This case study illustrates the complex dynamics of a community preservation campaign and ways Public History programs can support such efforts
A skewer survey of the Galactic halo from deep CFHT and INT images
We study the density profile and shape of the Galactic halo using deep
multicolour images from the MENeaCS and CCCP projects, over 33 fields selected
to avoid overlap with the Galactic plane. Using multicolour selection and PSF
homogenization techniques we obtain catalogues of F stars (near-main sequence
turnoff stars) out to Galactocentric distances up to 60kpc. Grouping nearby
lines of sight, we construct the stellar density profiles through the halo in
eight different directions by means of photometric parallaxes. Smooth halo
models are then fitted to these profiles. We find clear evidence for a
steepening of the density profile power law index around R=20 kpc, from -2.50
+- 0.04 to -4.85 +- 0.04, and for a flattening of the halo towards the poles
with best-fit axis ratio 0.63 +- 0.02. Furthermore, we cannot rule out a mild
triaxiality (w>=0.8). We recover the signatures of well-known substructure and
streams that intersect our lines of sight. These results are consistent with
those derived from wider but shallower surveys, and augur well for upcoming,
wide-field surveys of comparable depth to our pencil beam surveys.Comment: 14 pages, 8 figures, 6 table
The dynamics of z~1 clusters of galaxies from the GCLASS survey
We constrain the internal dynamics of a stack of 10 clusters from the GCLASS
survey at 0.87<z<1.34. We determine the stack cluster mass profile M(r) using
the MAMPOSSt algorithm of Mamon et al., the velocity anisotropy profile beta(r)
from the inversion of the Jeans equation, and the pseudo-phase-space density
profiles Q(r) and Qr(r), obtained from the ratio between the mass density
profile and the third power of the (total and, respectively, radial) velocity
dispersion profiles of cluster galaxies. Several M(r) models are statistically
acceptable for the stack cluster (Burkert, Einasto, Hernquist, NFW). The total
mass distribution has a concentration c=r200/r-2=4.0-0.6+1.0, in agreement with
theoretical expectations, and is less concentrated than the cluster
stellar-mass distribution. The stack cluster beta(r) is similar for passive and
star-forming galaxies and indicates isotropic galaxy orbits near the cluster
center and increasingly radially elongated with increasing cluster-centric
distance. Q(r) and Qr(r) are almost power-law relations with slopes similar to
those predicted from numerical simulations of dark matter halos. Combined with
results obtained for lower-z clusters we determine the dynamical evolution of
galaxy clusters, and compare it with theoretical predictions. We discuss
possible physical mechanisms responsible for the differential evolution of
total and stellar mass concentrations, and of passive and star-forming galaxy
orbits [abridged].Comment: 12 pages, 7 figures. Version accepted for publication in A&A after
minor modification
Finding halo streams with a pencil-beam survey: new wraps in the Sagittarius stream
We use data from two CFHT-MegaCam photometric pencil-beam surveys in the g'
and the r' bands to measure distances to the Sagittarius, the Palomar 5 and the
Orphan stream. We show that, using a cross-correlation algorithm to detect the
turnoff point of the main sequence, it is possible to overcome the main
limitation of a two-bands pencil-beam survey, namely the lack of adjacent
control-fields that can be used to subtract the foreground and background stars
to enhance the signal on the colour-magnitude diagrams (CMDs). We describe the
cross-correlation algorithm and its implementation. We combine the resulting
main sequence turnoff points with theoretical isochrones to derive photometric
distances to the streams. Our results (31 detections on the Sagittarius stream
and one each for the Palomar 5 and the Orphan streams) confirm the findings by
previous studies, expand the distance trend for the Sagittarius faint southern
branch and, for the first time, trace the Sagittarius faint branch of the
northern-leading arm out to 56 kpc. In addition, they show evidence for new
substructure: we argue that these detections trace the continuation of the
Sagittarius northern-leading arm into the southern hemisphere, and find a
nearby branch of the Sagittarius trailing wrap in the northern hemisphere.Comment: 16 pages, 15 figures, 2 table
Nanoparticle characterization: What to measure?
What to measure? is a key question in nanoscience, and it is not straightforward to address as different physicochemical properties define a nanoparticle sample. Most prominent among these properties are size, shape, surface charge, and porosity. Today researchers have an unprecedented variety of measurement techniques at their disposal to assign precise numerical values to those parameters. However, methods based on different physical principles probe different aspects, not only of the particles themselves, but also of their preparation history and their environment at the time of measurement. Understanding these connections can be of great value for interpreting characterization results and ultimately controlling the nanoparticle structure–function relationship. Here, the current techniques that enable the precise measurement of these fundamental nanoparticle properties are presented and their practical advantages and disadvantages are discussed. Some recommendations of how the physicochemical parameters of nanoparticles should be investigated and how to fully characterize these properties in different environments according to the intended nanoparticle use are proposed. The intention is to improve comparability of nanoparticle properties and performance to ensure the successful transfer of scientific knowledge to industrial real‐world applications
Efficient VLSI Implementation of Soft-input Soft-output Fixed-complexity Sphere Decoder
Fixed-complexity sphere decoder (FSD) is one of the most promising techniques for the implementation of multipleinput multiple-output (MIMO) detection, with relevant advantages in terms of constant throughput and high flexibility of parallel architecture. The reported works on FSD are mainly based on software level simulations and a few details have been provided on hardware implementation. The authors present the study based on a four-nodes-per-cycle parallel FSD architecture with several examples of VLSI implementation in 4 × 4 systems with both 16-quadrature amplitude modulation (QAM) and 64-QAM modulation and both real and complex signal models. The implementation aspects and details of the architecture are analysed in order to provide a variety of performance-complexity trade-offs. The authors also provide a parallel implementation of loglikelihood- ratio (LLR) generator with optimised algorithm to enhance the proposed FSD architecture to be a soft-input softoutput (SISO) MIMO detector. To the authors best knowledge, this is the first complete VLSI implementation of an FSD based SISO MIMO detector. The implementation results show that the proposed SISO FSD architecture is highly efficient and flexible, making it very suitable for real application
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