467 research outputs found
Concerning the quark condensate
A continuum expression for the trace of the massive dressed-quark propagator
is used to explicate a connection between the infrared limit of the QCD Dirac
operator's spectrum and the quark condensate appearing in the operator product
expansion, and the connection is verified via comparison with a lattice-QCD
simulation. The pseudoscalar vacuum polarisation provides a good approximation
to the condensate over a larger range of current-quark masses.Comment: 7 pages, LaTeX2e, revtex
The 20-Ne(p,n)20-Na Reaction at 120 MeV
This work was supported by the National Science Foundation Grant NSF PHY 81-14339 and by Indiana Universit
The Liverpool Statement 2005: Priorities for the European Union/United States Spiral Computed Tomography Collaborative Group
The Liverpool Statement 2005 was developed at the Fourth International Lung Cancer Molecular Biomarkers Workshop in Liverpool (October 27-29, 2005) and focused on the priorities for the European Union/United States (EU-US) Spiral Computed Tomography (CT) Collaborative Group. The application of spiral CT technology for early lung cancer screening has gained enormous momentum in the past 5 years. The EU-US Spiral CT Collaboration was initiated in 2001 in Liverpool, and subsequent meetings throughout Europe have resulted in the development of collaborative protocols and minimal data sets that provide a mechanism for the different trial groups to work together, with the ultimate aim to pool results. Considerable progress has been made with major national screening trials in the U.S. and Europe, which include IELCAP, NLST, and NELSON. The major objective of this international collaboration is the planned cross-analysis of the individual studies after they are reported. The EU-US researchers have agreed to a number of long-term objectives and to explore strategic areas for harmonization of complementary investigations
Flavin Fluorescence Dynamics and Photoinduced Electron Transfer in Escherichia coli Glutathione Reductase
Experimental Facilities Development
This research was sponsored by the National Science Foundation Grant NSF PHY 87-1440
Role of bulk and of interface contacts in the behaviour of model dimeric proteins
Some dimeric proteins first fold and then dimerize (three--state dimers)
while others first dimerize and then fold (two--state dimers). Within the
framework of a minimal lattice model, we can distinguish between sequences
obeying to one or to the other mechanism on the basis of the partition of the
ground state energy between bulk than for interface contacts. The topology of
contacts is very different for the bulk than for the interface: while the bulk
displays a rich network of interactions, the dimer interface is built up a set
of essentially independent contacts. Consequently, the two sets of interactions
play very different roles both in the the folding and in the evolutionary
history of the protein. Three--state dimers, where a large fraction of the
energy is concentrated in few contacts buried in the bulk, and where the
relative contact energy of interface contacts is considerably smaller than that
associated with bulk contacts, fold according to a hierarchycal pathway
controlled by local elementary structures, as also happens in the folding of
single--domain monomeric proteins. On the other hand, two--state dimers display
a relative contact energy of interface contacts which is larger than the
corresponding quantity associated with the bulk. In this case, the assembly of
the interface stabilizes the system and lead the two chains to fold. The
specific properties of three--state dimers acquired through evolution are
expected to be more robust than those of two--state dimers, a fact which has
consequences on proteins connected with viral diseases
An Integrated TCGA Pan-Cancer Clinical Data Resource to Drive High-Quality Survival Outcome Analytics
For a decade, The Cancer Genome Atlas (TCGA) program collected clinicopathologic annotation data along with multi-platform molecular profiles of more than 11,000 human tumors across 33 different cancer types. TCGA clinical data contain key features representing the democratized nature of the data collection process. To ensure proper use of this large clinical dataset associated with genomic features, we developed a standardized dataset named the TCGA Pan-Cancer Clinical Data Resource (TCGA-CDR), which includes four major clinical outcome endpoints. In addition to detailing major challenges and statistical limitations encountered during the effort of integrating the acquired clinical data, we present a summary that includes endpoint usage recommendations for each cancer type. These TCGA-CDR findings appear to be consistent with cancer genomics studies independent of the TCGA effort and provide opportunities for investigating cancer biology using clinical correlates at an unprecedented scale. Analysis of clinicopathologic annotations for over 11,000 cancer patients in the TCGA program leads to the generation of TCGA Clinical Data Resource, which provides recommendations of clinical outcome endpoint usage for 33 cancer types
Editor's Choice - Infective Native Aortic Aneurysms: A Delphi Consensus Document on Terminology, Definition, Classification, Diagnosis, and Reporting Standards.
There is no consensus regarding the terminology, definition, classification, diagnostic criteria, and algorithm, or reporting standards for the disease of infective native aortic aneurysm (INAA), previously known as mycotic aneurysm. The aim of this study was to establish this by performing a consensus study.
The Delphi methodology was used. Thirty-seven international experts were invited via mail to participate. Four two week Delphi rounds were performed, using an online questionnaire, initially with 22 statements and nine reporting items. The panellists rated the statements on a five point Likert scale. Comments on statements were analysed, statements revised, and results presented in iterative rounds. Consensus was defined as ≥ 75% of the panel selecting "strongly agree" or "agree" on the Likert scale, and consensus on the final assessment was defined as Cronbach's alpha coefficient > .80.
All 38 panellists completed all four rounds, resulting in 100% participation and agreement that this study was necessary, and the term INAA was agreed to be optimal. Three more statements were added based on the results and comments of the panel, resulting in a final 25 statements and nine reporting items. All 25 statements reached an agreement of ≥ 87%, and all nine reporting items reached an agreement of 100%. The Cronbach's alpha increased for each consecutive round (round 1 = .84, round 2 = .87, round 3 = .90, and round 4 = .92). Thus, consensus was reached for all statements and reporting items.
This Delphi study established the first consensus document on INAA regarding terminology, definition, classification, diagnostic criteria, and algorithm, as well as reporting standards. The results of this study create essential conditions for scientific research on this disease. The presented consensus will need future amendments in accordance with newly acquired knowledge
- …