8,781 research outputs found
New Aspects of Thromboangiitis obliterans (von Winiwarter-Buerger's Disease)
The existence of thromboangiitis obliterans as a clinical entity has been a matter of debate for many years. In contrast to other immunovasculitides there is no organ involvement while peripheral vessels are affected. Heavy smokers under 40 years of age have a high predisposition for the disease. The cerebral form shows relapsing brain infarctions which can be visualized in CCT while panarteriography remains negative. Apart from unspecific inflammatory signs in blood and CSF there are distinctive laboratory findings proving the autoimmunological character of von Winiwarter-Buerger's disease. In the serum anti-elastin antibodies, IgE and anticollagen antibody activity are detectable. In 3 patients the authors detected specific immunohistochemical findings in a biopsy specimen of the temporal artery. In addition to platelet-inhibiting substances corticoids in acute and azathioprine in chronic treatment becomes necessary
Measurement of the elastic scattering cross section of neutrons from argon and neon
Background: The most significant source of background in direct dark matter
searches are neutrons that scatter elastically from nuclei in the detector's
sensitive volume. Experimental data for the elastic scattering cross section of
neutrons from argon and neon, which are target materials of interest to the
dark matter community, were previously unavailable. Purpose: Measure the
differential cross section for elastic scattering of neutrons from argon and
neon in the energy range relevant to backgrounds from (alpha,n) reactions in
direct dark matter searches. Method: Cross-section data were taken at the
Triangle Universities Nuclear Laboratory (TUNL) using the neutron
time-of-flight technique. These data were fit using the spherical optical
model. Results: The differential cross section for elastic scatting of neutrons
from neon at 5.0 and 8.0 MeV and argon at 6.0 MeV was measured. Optical-model
parameters for the elastic scattering reactions were determined from the best
fit to these data. The total elastic scattering cross section for neon was
found to differ by 6% at 5.0 MeV and 13% at 8.0 MeV from global optical-model
predictions. Compared to a local optical-model for 40Ar, the elastic scattering
cross section was found to differ from the data by 8% at 6.0 MeV. Conclusions:
These new data are important for improving Monte-Carlo simulations and
background estimates for direct dark matter searches and for benchmarking
optical models of neutron elastic scattering from these nuclei
Floor Mapping: A Novel Method of Integrating Anatomical Structure with Immunological Function
Session - Assessment (Abstract)This free journal suppl. entitled: Special Issue: Abstracts of the 13th Asia Pacific Medical Education Conference (APMEC) ... 2016The Biomedical Common Year 1 occurs prior to admission to the
medical programme. Students achieving a grade point average
over 6.0 are eligible for an admissions interview. The research
question of the study was, âIf students have a definite interest in
becoming a future doctor in their premedical course, does this
relate to their levels of motivation, competitiveness, perceived
stress, quality of life and grade attainment?â A total of 1369
students who completed a high stakes biosciences assessment
were asked to disclose their grade (converted to a numerical
value) and to complete the Motivated Strategies for Learning
Questionnaire, a World Health Organisation Quality Of Life
(QoL) questionnaire, Perceived Stress Scale, and Revised
Competitiveness Index. To explore differences between those
students who aimed to be doctors vs those who did not, a binary
logistic regression was conducted. Twenty five percent of students
participated in the research. Significant predictors of course
intention (medicine; other) were academic attainment, perceived
stress, and physical and environmental QoL. Post hoc analyses
revealed that perceived stress and physical QoL were moderating
variables. Students with an intention to become a doctor tend to
attain higher grades and have better environmental quality of life
scores. This may indicate that students who are admitted into
medical school gain higher grades but also likely come from
more affluent and well-resourced backgrounds. Physical health
problems and perceived stress are likely to moderate the impact
of grade achievement, environmental QoL, competition and
motivation.link_to_OA_fulltex
Dust rings and filaments around the isolated young star V1331 Cygni
We characterize the small and large scale environment of the young star V1331
Cygni with high resolution HST/WFPC2 and Digitized Sky Survey images. In
addition to a previously known outer dust ring (~30'' in diameter), the
HST/WFPC2 scattered light image reveals an inner dust ring for the first time.
This ring has a maximum radius of 6.5'' and is possibly related to a molecular
envelope. Large-scale optical images show that V1331 Cyg is located at the tip
of a long dust filament linking it to the dark cloud LDN 981. We discuss the
origin of the observed dust morphology and analyze the object's relation to its
parent dark cloud LDN 981. Finally, based on recent results from the
literature, we investigate the properties of V1331 Cyg and conclude that in its
current state the object does not show suffcient evidence to be characterized
as an FU Ori object.Comment: 15 pages ApJ preprint style including 3 figures, accepted for
publication in ApJ (Feb. 2007
Nonlinear propagation of planet-generated tidal waves
The propagation and evolution of planet-generated density waves in
protoplanetary disks is considered. The evolution of waves, leading to the
shock formation and wake dissipation, is followed in the weakly nonlinear
regime. The local approach of Goodman & Rafikov (2001) is extended to include
the effects of surface density and temperature variations in the disk as well
as the disk cylindrical geometry and nonuniform shear. Wave damping due to
shocks is demonstrated to be a nonlocal process spanning a significant fraction
of the disk. Torques induced by the planet could be significant drivers of disk
evolution on timescales of the order 1-10 Myr even in the absence of strong
background viscosity. A global prescription for angular momentum deposition is
developed which could be incorporated into the study of gap formation in a
gaseous disk around the planet.Comment: AASTeX, 26 pages, 4 figures, 1 table, submitted to Ap
Very Low-Mass Objects in the Coronet Cluster: The Realm of the Transition Disks
We present optical and IR spectra of a set of low-mass stars and brown dwarfs
in the Coronet cluster (aged ~1Myr), obtained with the multifiber spectrograph
FLAMES/VLT and IRS/Spitzer. The optical spectra reveal spectral types between
M1 and M7.5, confirm the youth of the objects (via Li 6708 A absorption), and
show the presence of accretion (via Halpha) and shocks (via forbidden line
emission). The IRS spectra, together with IR photometry from the IRAC/MIPS
instruments on Spitzer and 2MASS, confirm the presence of IR excesses
characteristic of disks around ~70% of the objects. Half of the disks do not
exhibit any silicate emission, or present flat features characteristic of large
grains. The rest of the disks show silicate emission typical of amorphous and
crystalline silicate grains a few microns in size. About 50% of the objects
with disks do not show near-IR excess emission, having "transitional" disks,
according to their classical definition. This is a very high fraction for such
a young cluster. The large number of "transitional" disks suggests lifetimes
comparable to the lifetimes of typical optically thick disks. Therefore, these
disks may not be in a short-lived phase, intermediate between Class II and
Class III objects. The median spectral energy distribution of the disks in the
Coronet cluster is also closer to a flat disk than observed for the disks
around solar-type stars in regions with similar age. The differences in the
disk morphology and evolution in the Coronet cluster could be related to fact
that these objects have very late spectral types compared to the solar-type
stars in other cluster studies. Finally, the optical spectroscopy reveals that
one of the X-ray sources is produced by a Herbig Haro object in the cloud.Comment: 51 pages, 13 figures, 10 table
Sampling forages for best use
"You can improve your livestock feeding program by using reliable forage analyses to plan and balance rations. However, laboratory analyses are only useful if the sample represents what your animals will eat."--First page.Jimmy C. Henning and Norman R. Risner (Agronomy Department)New 7/88/75
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