916 research outputs found
Hiding the complexity: building a distributed ATLAS Tier-2 with a single resource interface using ARC middleware
Since their inception, Grids for high energy physics have found management of data to be the most challenging aspect of operations. This problem has generally been tackled by the experiment's data management framework controlling in fine detail the distribution of data around the grid and the careful brokering of jobs to sites with co-located data. This approach, however, presents experiments with a difficult and complex system to manage as well as introducing a rigidity into the framework which is very far from the original conception of the grid.<p></p>
In this paper we describe how the ScotGrid distributed Tier-2, which has sites in Glasgow, Edinburgh and Durham, was presented to ATLAS as a single, unified resource using the ARC middleware stack. In this model the ScotGrid 'data store' is hosted at Glasgow and presented as a single ATLAS storage resource. As jobs are taken from the ATLAS PanDA framework, they are dispatched to the computing cluster with the fastest response time. An ARC compute element at each site then asynchronously stages the data from the data store into a local cache hosted at each site. The job is then launched in the batch system and accesses data locally.<p></p>
We discuss the merits of this system compared to other operational models and consider, from the point of view of the resource providers (sites), and from the resource consumers (experiments); and consider issues involved in transitions to this model
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Race Gaps in School Trust: Where They Come from and How to Resolve Them
Trust in American institutions varies widely among adults from different racial-ethnic backgrounds. This brief, from PRC faculty research associate David Yeager and colleagues, demonstrates that unjust treatment causes minority adolescents to lose trust in school, but a respectful "wise feedback" intervention can repair distrust.Population Research Cente
Predicting return to work from health related welfare following low intensity cognitive behaviour therapy
The aim of this study was to identify predictors of return to work in the short and long
term following condition management cognitive-behavioural therapy (CM-CBT). All
participants (N = 3794) were disability welfare claimants, unemployed due to the
presence of a physical or mental health condition. CM-CBT consisted of a seven
session group cognitive-behavioural psychoeducational programme, with participants
followed-up at 3 and 12-30 months. The primary employment outcome measure was
a categorical measure of either returned to work, made progress towards work or
remained on welfare. Results index an incremental progress and return to work rate,
increasing from 34.41 % at short-term follow-up to 53.07 % at long-term follow-up.
Clinically, 17.40 % were classed as recovered following CM-CBT. Reliable
psychological change during CM-CBT predicted successful return to work and
remaining on welfare was associated with psychological regression over time. The
results are discussed in terms of identified methodological weaknesses and the
potential of CBT in enabling return to work for the health related unemployed
Multi-core job submission and grid resource scheduling for ATLAS AthenaMP
AthenaMP is the multi-core implementation of the ATLAS software framework and allows the efficient sharing of memory pages between multiple threads of execution. This has now been validated for production and delivers a significant reduction on the overall application memory footprint with negligible CPU overhead. Before AthenaMP can be routinely run on the LHC Computing Grid it must be determined how the computing resources available to ATLAS can best exploit the notable improvements delivered by switching to this multi-process model. A study into the effectiveness and scalability of AthenaMP in a production environment will be presented. Best practices for configuring the main LRMS implementations currently used by grid sites will be identified in the context of multi-core scheduling optimisation
Decreased expression of the Id3 gene at 1p36.1 in ovarian adenocarcinomas
The molecular events that drive the initiation and progression of ovarian adenocarcinoma are not well defined. We have investigated changes in gene expression in ovarian cancer cell lines compared to an immortalized human ovarian surface epithelial cell line (HOSE) using a cDNA array. We identified 17 genes that were under-expressed and 10 genes that were over-expressed in the cell lines compared to the HOSE cells. One of the genes under-expressed in the ovarian cancer cell lines, Id3, a transcriptional inactivator, was selected for further investigation. Id3 mRNA was expressed at reduced levels in 6 out of 9 ovarian cancer cell lines compared to the HOSE cells while at the protein level, all 7 ovarian cancer cell lines examined expressed the Id3 protein at greatly reduced levels. Expression of Id3 mRNA was also examined in primary ovarian tumours and was found in only 12/38 (32%) cases. A search was conducted for mutations of Id3 in primary ovarian cancers using single stranded conformation polymorphism (SSCP) analysis. Only one nucleotide substitution, present also in the corresponding constitutional DNA, was found in 94 ovarian tumours. Furthermore no association was found between LOH at 1p36 and lack of expression of Id3. These data suggest that Id3 is not the target of LOH at 1p36. © 2001 Cancer Research Campaign http://www.bjcancer.co
Polyvalent diazonium polymers provide efficient protection of oncolytic adenovirus Enadenotucirev from neutralising antibodies while maintaining biological activity in vitro and in vivo
Oncolytic viruses offer many advantages for cancer therapy when administered directly to confined solid tumors. However, the systemic delivery of these viruses is problematic due to host immune response, undesired interactions with blood components and inherent targeting to the liver. Efficacy of systemically administered viruses has been improved by masking viral surface proteins with polymeric materials, through modulation of viral pharmacokinetic profile and accumulation in tumors in vivo. Here we describe a new class of polyvalent reactive based upon poly(N-(2-hydroxypropyl)methacrylamide) (polyHPMA) with diazonium reactive groups and their application in the modification of the chimeric oncolytic virus Enadenotucirev (EnAd). A series of six reactive copolymers with different chain lengths and density of reactive groups was synthesised and used to coat EnAd. Polymer coating was found to be extremely efficient with concentrations as low as 1 mg/mL resulting in complete (>99%) ablation of neutralising antibody binding. Coating efficiency was found to be dependent on both chain length and reactive group density. Coated viruses were found to have reduced transfection activity both in vitro and in vivo with greater protection against neutralising antibodies resulting in lower transgene production. However, in the presence of neutralising antibodies some in vivo transgene expression was maintained for coated virus compared to the uncoated control. Reduction in transgene expression was found to not be solely due to reduced cellular uptake but due to reducing unpackaging of the virus within the cells and reducing replication indicating that polymer coating does not cause permanent inactivation of the virus. These data suggest that virus activity may be modulated by appropriate design of coating polymers while retaining protection against neutralising antibodies
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