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Grid Interoperation with ARC middleware for the CMS experiment

Erik Edelmann, Laurence Field, Jaime Frey, Michael Grønager, Kalle Happonen, Daniel Johansson, Josva Kleist, Jukka Klem, Jesper Koivumäki, Tomas Lindén, Antti Pirinen, Di Qing
2010 Journal of Physics, Conference Series  
The Compact Muon Solenoid (CMS) is one of the general purpose experiments at the CERN Large Hadron Collider (LHC). CMS computing relies on different grid infrastructures to provide computational and storage resources. The major grid middleware stacks used for CMS computing are gLite, Open Science Grid (OSG) and ARC (Advanced Resource Connector). Helsinki Institute of Physics (HIP) hosts one of the Tier2 centers for CMS computing. CMS Tier2 centers operate software systems for data transfers
more » ... DEx), Monte Carlo production (ProdAgent) and data analysis (CRAB). In order to provide the Tier2 services for CMS, HIP uses tools and components from both ARC and gLite grid middleware stacks. Interoperation between grid systems is a challenging problem and HIP uses two different solutions to provide the needed services. The first solution is based on gLiteARC grid level interoperability. This allows to use ARC resources in CMS without modifying the CMS application software. The second solution is based on developing specific ARC plugins in CMS software.
doi:10.1088/1742-6596/219/6/062016 fatcat:wbohu2mdkbczlh3twgszwzkfee

Investigations of the Navβ1b sodium channel subunit in human ventricle; functional characterization of the H162P Brugada syndrome mutant

Lei Yuan, Jussi T. Koivumäki, Bo Liang, Lasse G. Lorentzen, Chuyi Tang, Martin N. Andersen, Jesper H. Svendsen, Jacob Tfelt-Hansen, Molly Maleckar, Nicole Schmitt, Morten S. Olesen, Thomas Jespersen
2014 American Journal of Physiology. Heart and Circulatory Physiology  
Brugada syndrome (BrS) is a rare inherited disease that can give rise to ventricular arrhythmia and ultimately sudden cardiac death. Numerous loss-of-function mutations in the cardiac sodium channel Nav1.5 have been associated with BrS. However, few mutations in the auxiliary Na v␤1-4 subunits have been linked to this disease. Here we investigated differences in expression and function between Nav␤1 and Nav␤1b and whether the H162P/ Na v␤1b mutation found in a BrS patient is likely to be the
more » ... erlying cause of disease. The impact of Nav␤ subunits was investigated by patch-clamp electrophysiology, and the obtained in vitro values were used for subsequent in silico modeling. We found that Na v␤1b transcripts were expressed at higher levels than Nav␤1 transcripts in the human heart. Nav␤1 and Nav␤1b coexpressed with Nav1.5 induced a negative shift on steady state of activation and inactivation compared with Nav1.5 alone. Furthermore, Nav␤1b was found to increase the current level when coexpressed with Nav1.5, Nav␤1b/ H162P mutated subunit peak current density was reduced by 48% (Ϫ645 Ϯ 151 vs. Ϫ334 Ϯ 71 pA/pF), V1/2 steady-state inactivation shifted by Ϫ6.7 mV (Ϫ70.3 Ϯ 1.5 vs. Ϫ77.0 Ϯ 2.8 mV), and time-dependent recovery from inactivation slowed by Ͼ50% compared with coexpression with Na v␤1b wild type. Computer simulations revealed that these electrophysiological changes resulted in a reduction in both action potential amplitude and maximum upstroke velocity. The experimental data thereby indicate that Nav␤1b/H162P results in reduced sodium channel activity functionally affecting the ventricular action potential. This result is an important replication to support the notion that BrS can be linked to the function of Nav␤1b and is associated with loss-of-function of the cardiac sodium channel. Brugada syndrome; electrophysiology; sodium current; ventricular arrhythmia; computer simulation THE NA V 1.5 ION CHANNEL PROTEIN, encoded by SCN5A, forms the ␣-subunit of the cardiac voltage-gated sodium current (I Na ). Mutations in SCN5A have been shown to play a central role in several cardiac rhythm disorders, including Brugada syndrome (BrS), long QT Syndrome (LQTS), conduction
doi:10.1152/ajpheart.00405.2013 pmid:24561865 fatcat:dbtrtahjqfhl5ktqzz3fwl22lm

Distributed Analysis in CMS

Alessandra Fanfani, Anzar Afaq, Jose Afonso Sanches, Julia Andreeva, Giusepppe Bagliesi, Lothar Bauerdick, Stefano Belforte, Patricia Bittencourt Sampaio, Ken Bloom, Barry Blumenfeld, Daniele Bonacorsi, Chris Brew (+67 others)
2010 Journal of Grid Computing  
The CMS experiment expects to manage several Pbytes of data each year during the LHC programme, distributing them over many A. Fanfani et al. location for physics analysis to support a wide community with thousands potential users. This represents an unprecedented experimental challenge in terms of the scale of distributed computing resources and number of user. An overview of the computing architecture, the software tools and the distributed infrastructure is reported. Summaries of the
more » ... ce in establishing efficient and scalable operations to get prepared for CMS distributed analysis are presented, followed by the user experience in their current analysis activities.
doi:10.1007/s10723-010-9152-1 fatcat:jvs2ccg7r5em7b3vringhmobye