737 research outputs found
Collision of adenocarcinoma and gastrointestinal stromal tumour (GIST) in the stomach: report of a case
A 78-year-old woman was diagnosed with a proximal gastric adenocarcinoma and underwent an elective D2 total gastrectomy with splenectomy. Subsequent histopathology revealed the presence of another tumour at the gastric antrum. This was a small benign gastrointestinal stromal tumour (GIST) mixed with gastric adenocarcinoma cells similar to those of the main gastric tumour i.e. a collision tumour. The literature has only few previous reports of this very rare association. It is not known whether this synchronicity is incidental or there is a causative factor inducing the development of tumours of different histotypes in the same organ. Pathologists, oncologists and surgeons should be aware of this interesting condition
Adjacent thoracic lymph node metastases originating from two separate primary cancers: case report
Reported is an unusual case of adjacent thoracic lymph nodes demonstrating metastases from two different primary malignancies. A 51 year-old woman with a previous history of bilateral breast cancer underwent a radical gastro-oesophagectomy for adenocarcinoma of the lower third of the oesophagus. The resection specimen demonstrated breast and oesophageal metastases in adjacent thoracic lymph nodes. Mechanisms for this phenomenon, including the known local immune suppression on lymphoid cells by oesophageal carcinoma cells, are discussed
Study of Gluon versus Quark Fragmentation in and Events at \sqrt{s}=10 GeV
Using data collected with the CLEO II detector at the Cornell Electron
Storage Ring, we determine the ratio R(chrg) for the mean charged multiplicity
observed in Upsilon(1S)->gggamma events, to the mean charged multiplicity
observed in e+e- -> qqbar gamma events. We find R(chrg)=1.04+/-0.02+/-0.05 for
jet-jet masses less than 7 GeV.Comment: 15 pages, postscript file also available through
http://w4.lns.cornell.edu/public/CLN
Performance of the CMS Cathode Strip Chambers with Cosmic Rays
The Cathode Strip Chambers (CSCs) constitute the primary muon tracking device
in the CMS endcaps. Their performance has been evaluated using data taken
during a cosmic ray run in fall 2008. Measured noise levels are low, with the
number of noisy channels well below 1%. Coordinate resolution was measured for
all types of chambers, and fall in the range 47 microns to 243 microns. The
efficiencies for local charged track triggers, for hit and for segments
reconstruction were measured, and are above 99%. The timing resolution per
layer is approximately 5 ns
The search for transient astrophysical neutrino emission with IceCube-DeepCore
We present the results of a search for astrophysical sources of brief transient neutrino emission using IceCube and DeepCore data acquired between 2012 May 15 and 2013 April 30. While the search methods employed in this analysis are similar to those used in previous IceCube point source searches, the data set being examined consists of a sample of predominantly sub-TeV muon-neutrinos from the Northern Sky (-5 degrees < delta < 90 degrees) obtained through a novel event selection method. This search represents a first attempt by IceCube to identify astrophysical neutrino sources in this relatively unexplored energy range. The reconstructed direction and time of arrival of neutrino events are used to search for any significant self-correlation in the data set. The data revealed no significant source of transient neutrino emission. This result has been used to construct limits at timescales ranging from roughly 1 s to 10 days for generic soft-spectra transients. We also present limits on a specific model of neutrino emission from soft jets in core-collapse supernovae
Determining neutrino oscillation parameters from atmospheric muon neutrino disappearance with three years of IceCube DeepCore data
We present a measurement of neutrino oscillations via atmospheric muon
neutrino disappearance with three years of data of the completed IceCube
neutrino detector. DeepCore, a region of denser instrumentation, enables the
detection and reconstruction of atmospheric muon neutrinos between 10 GeV and
100 GeV, where a strong disappearance signal is expected. The detector volume
surrounding DeepCore is used as a veto region to suppress the atmospheric muon
background. Neutrino events are selected where the detected Cherenkov photons
of the secondary particles minimally scatter, and the neutrino energy and
arrival direction are reconstructed. Both variables are used to obtain the
neutrino oscillation parameters from the data, with the best fit given by
and
(normal mass hierarchy assumed). The
results are compatible and comparable in precision to those of dedicated
oscillation experiments.Comment: 10 pages, 7 figure
The IceCube Neutrino Observatory - Contributions to ICRC 2015 Part II: Atmospheric and Astrophysical Diffuse Neutrino Searches of All Flavors
Papers on atmospheric and astrophysical diffuse neutrino searches of all
flavors submitted to the 34th International Cosmic Ray Conference (ICRC 2015,
The Hague) by the IceCube Collaboration.Comment: 66 pages, 36 figures, Papers submitted to the 34th International
Cosmic Ray Conference, The Hague 2015, v2 has a corrected author lis
Flavor Ratio of Astrophysical Neutrinos above 35 TeV in IceCube
A diffuse flux of astrophysical neutrinos above has been
observed at the IceCube Neutrino Observatory. Here we extend this analysis to
probe the astrophysical flux down to and analyze its flavor
composition by classifying events as showers or tracks. Taking advantage of
lower atmospheric backgrounds for shower-like events, we obtain a shower-biased
sample containing 129 showers and 8 tracks collected in three years from 2010
to 2013. We demonstrate consistency with the
flavor ratio at Earth
commonly expected from the averaged oscillations of neutrinos produced by pion
decay in distant astrophysical sources. Limits are placed on non-standard
flavor compositions that cannot be produced by averaged neutrino oscillations
but could arise in exotic physics scenarios. A maximally track-like composition
of is excluded at , and a purely shower-like
composition of is excluded at .Comment: 8 pages, 3 figures. Submitted to PR
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