19,322 research outputs found
EU DataGRID testbed management and support at CERN
In this paper we report on the first two years of running the CERN testbed
site for the EU DataGRID project. The site consists of about 120 dual-processor
PCs distributed over several testbeds used for different purposes: software
development, system integration, and application tests. Activities at the site
included test productions of MonteCarlo data for LHC experiments, tutorials and
demonstrations of GRID technologies, and support for individual users analysis.
This paper focuses on node installation and configuration techniques, service
management, user support in a gridified environment, and includes
considerations on scalability and security issues and comparisons with
"traditional" production systems, as seen from the administrator point of view.Comment: Talk from the 2003 Computing in High Energy and Nuclear Physics
(CHEP03), La Jolla, Ca, USA, March 2003, 7 pages, LaTeX. PSN THCT00
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Innovative Approaches to Emergency Medical Services Fellowship Challenges
Introduction: Since the development of an Accreditation Council of Graduate Medical Education (ACGME)-accredited emergency medical services (EMS) fellowship, there has been little published literature on effective methods of content delivery or training modalities. Here we explore a variety of innovative approaches to the development and revision of the EMS fellowship curriculum.Methods: Three academic, university-based ACGME-accredited EMS fellowship programs each implemented an innovative change to their existing training curricula. These changes included the following: a novel didactic curriculum delivery modality and evaluation; implementation of a distance education program to improve EMS fellows’ rural EMS experiences; and modification of an existing EMS fellowship curriculum to train a non-emergency medicine physician.Results: Changes made to each of the above EMS fellowship programs addressed unique challenges, demonstrating areas of success and promise for more generalized implementation of these curricula. Obstacles remain in tailoring the described curricula to the needs of each unique institution and system.Conclusion: Three separate curricula and program changes were implemented to overcome specific challenges and achieve educational goals. It is our hope that our shared experiences will enable others in addressing common barriers to teaching the EMS fellowship core content and share similar innovative approaches to educational challenges
Slave-boson approach to the metallic stripe phases with large unit cells
Using a rotationally invariant version of the slave-boson approach in spin
space we analyze the stability of stripe phases with large unit cells in the
two-dimensional Hubbard model. This approach allows one to treat strong
electron correlations in the stripe phases relevant in the low doping regime,
and gives results representative of the thermodynamic limit. Thereby we resolve
the longstanding controversy concerning the role played by the kinetic energy
in stripe phases. While the transverse hopping across the domain walls yields
the largest kinetic energy gain in the case of the insulating stripes with one
hole per site, the holes propagating along the domain walls stabilize the
metallic vertical stripes with one hole per two sites, as observed in the
cuprates. We also show that a finite next-nearest neighbor hopping can tip
the energy balance between the filled diagonal and half-filled vertical
stripes, which might explain a change in the spatial orientation of stripes
observed in the high cuprates at the doping .Comment: 16 pages, 14 figure
Decreased expression of p57KIP2mRNA in human bladder cancer
To identify targets of genetic and epigenetic alterations on chromosome 11p15.5 in human bladder cancer, expression of the imprinted KIP2, IGF2 and H19 genes was studied by quantitative RT-PCR in 24 paired samples of urothelial carcinomas and morphologically normal mucosa obtained by cystectomy, and in bladder carcinoma cell lines. The most frequent alteration in tumour tissue was decreased expression of KIP2 identified in 9/24 (37%) specimens. Decreased IGF2 and H19 mRNA levels were found in five (21%) and three (13%) tumours, respectively. One tumour each overexpressed IGF2 and H19. Loss of H19 expression was only found associated with loss of KIP2 expression, whereas decreased expression of IGF2 mRNA occurred independently. Almost all bladder carcinoma cell lines showed significant changes in the expression of at least one gene with diminished expression of KIP2 mRNA as the most frequent alteration. IGF2 mRNA levels were diminished in several lines, but increased in others. The KIP2 gene could be an important target of genetic and epigenetic alterations in bladder cancer affecting the maternal chromosome 11p15.5. However, reminiscent of the situation in Wilms’ tumours, expression of the IGF2 gene on the paternal chromosome can also be disturbed in bladder cancers. © 2000 Cancer Research Campaig
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