Efficient Parallel Multi-way Merging on Heterogeneous Multi-core Cluster

ABSTRACT A variety of large-scale diffuse radio structures have been identified in many clusters with the advent of new state-of-the-art facilities in radio astronomy. Among these diffuse radio structures, radio mini-halos are found in the central regions of cool core clusters. Their origin is still unknown and they are challenging to discover; less than 30 have been published to date. Based on new VLA observations, we confirmed the mini-halo in the massive strong cool core cluster PKS 0745−191 (z = 0.1028) and discovered one in the massive cool core cluster MACS J1447.4+0827 (z = 0.3755). Furthermore, using a detailed analysis of all known mini-halos, we explore the relation between mini-halos and active galactic nucleus (AGN) feedback processes from the central galaxy. We find evidence of strong, previously unknown correlations between mini-halo radio power and X-ray cavity power, and between mini-halo and the central galaxy radio power related to the relativistic jets when spectrally decomposing the AGN radio emission into a component for past outbursts and one for ongoing accretion. Overall, our study indicates that mini-halos are directly connected to the central AGN in clusters, following previous suppositions. We hypothesize that AGN feedback may be one of the dominant mechanisms giving rise to mini-halos by injecting energy into the intra-cluster medium and reaccelerating an old population of particles, while sloshing motion may drive the overall shape of mini-halos inside cold fronts. AGN feedback may therefore not only play a vital role in offsetting cooling in cool core clusters, but may also play a fundamental role in re-energizing non-thermal particles in clusters.

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Ein Konzept für die Leistungsanalyse von Multi-core Cluster-Computern

PIK - Praxis der Informationsverarbeitung und Kommunikation ◽

10.1515/pik-2014-0012 ◽

2014 ◽

Vol 0 (0) ◽

Author(s):

Heinz Kredel ◽

Hans Günther Kruse ◽

Sabine Richling

Keyword(s):

Core Cluster

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Validity Evidence for the Medical Student Core Physical Examination

10.21203/rs.3.rs-699718/v1 ◽

2021 ◽

Author(s):

Todd Guth ◽

Yoon Soo Park ◽

Janice Hanson ◽

Rachel Yudkowsky

Keyword(s):

Medical Students ◽

Clinical Skills ◽

Validity Evidence ◽

Clinical Experiences ◽

Colorado School ◽

The Core ◽

University Of Colorado ◽

School Of Medicine ◽

Core Cluster ◽

Cut Score

Abstract Background The Core Physical Exam (CPE) has been proposed as a set of key physical exam (PE) items for teaching and assessing PE skills in medical students, and as the basis of a Core + Cluster curriculum. Beyond the initial development of the CPE and proposal of the CPE and the Core + Cluster curriculum, no additional validity evidence has been presented for use of the CPE to teach or assess PE skills of medical students. As a result, a modified version of the CPE was developed by faculty at the University of Colorado School of Medicine (UCSOM) and implemented in the school’s clinical skills course in the context of an evolving Core + Cluster curriculum. Methods Validity evidence for the 25-item University of Colorado School of Medicine (UCSOM) CPE was analyzed using longitudinal assessment data from 366 medical students (Classes of 2019 and 2020), obtained from September 2015 through December 2019. Using Messick's unified validity framework, validity evidence specific to content, response process, internal structure, relationship to other variables, and consequences was gathered. Results Content and response process validity evidence included expert content review and rater training. For internal structure, a generalizability study phi coefficient of 0.258 suggests low reliability for a single assessment due to variability in learner performance by occasion and CPE items. Correlations of performance on the UCSOM CPE with other PE assessments were low, ranging from .00-.34. Consequences were explored through determination of a pass-fail cut score. Following a modified Angoff process, clinical skills course directors selected a consensus pass-fail cut score of 80% as a defensible and practical threshold for entry into precepted clinical experiences. Conclusions Validity evidence supports the use of the UCSOM CPE as an instructional strategy for teaching PE skills and as a formative assessment of readiness for precepted clinical experiences. The low generalizability coefficient suggests that inferences about PE skills based on the UCSOM CPE alone should be made with caution, and that the UCSOM CPE in isolation should be used primarily as a formative assessment.

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Association between ALS and retroviruses: evidence from bioinformatics analysis

BMC Bioinformatics ◽

10.1186/s12859-019-3249-8 ◽

2019 ◽

Vol 20 (S24) ◽

Author(s):

Jon P. Klein ◽

Zhifu Sun ◽

Nathan P. Staff

Keyword(s):

Protein Interaction ◽

Drug Targets ◽

Large Scale ◽

Bioinformatics Analysis ◽

Enrichment Analysis ◽

Protein Interaction Networks ◽

Interaction Networks ◽

Pathway Enrichment Analysis ◽

Protein Database ◽

Core Cluster

Abstract Background Emerging evidence suggests retroviruses play a role in the pathophysiology of amyotrophic lateral sclerosis (ALS). Specifically, activation of ancient viral genes embedded in the human genome is theorized to lead to motor neuron degeneration. We explore whether connections exist between ALS and retroviruses through protein interaction networks (PIN) and pathway analysis, and consider the potential roles in drug target discovery. Protein database and pathway/network analytical software including Ingenuity Pathway BioProfiler, STRING, and CytoScape were utilized to identify overlapping protein interaction networks and extract core cluster (s) of retroviruses and ALS. Results Topological and statistical analysis of the ALS-PIN and retrovirus-PIN identified a shared, essential protein network and a core cluster with significant connections with both networks. The identified core cluster has three interleukin molecules IL10, Il-6 and IL-1B, a central apoptosis regulator TP53, and several major transcription regulators including MAPK1, ANXA5, SQSTM1, SREBF2, and FADD. Pathway enrichment analysis showed that this core cluster is associated with the glucocorticoid receptor singling and neuroinflammation signaling pathways. For confirmation purposes, we applied the same methodology to the West Nile and Polio virus, which demonstrated trivial connectivity with ALS, supporting the unique connection between ALS and retroviruses. Conclusions Bioinformatics analysis provides evidence to support pathological links between ALS and retroviral activation. The neuroinflammation and apoptotic regulation pathways are specifically implicated. The continuation and further analysis of large scale genome studies may prove useful in exploring genes important in retroviral activation and ALS, which may help discover new drug targets.

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Nuclear structure properties of spin-1/2 heavy nuclei within the relativistic cluster model

International Journal of Modern Physics E ◽

10.1142/s0218301320500263 ◽

2020 ◽

Vol 29 (05) ◽

pp. 2050026

Author(s):

Keivan Darooyi Divshali ◽

Mohammad Reza Shojaei

Keyword(s):

Nuclear Structure ◽

Beta Decay ◽

Ground State ◽

Cluster Model ◽

Heavy Nuclei ◽

Core Cluster ◽

Phenomenological Potential ◽

The Stability ◽

Uvarov Method ◽

Structure Properties

[Formula: see text]C is a beta decay isotope, its beta decay is very slow reflecting the stability of this nucleus and emitted from medium and heavy mass nuclei. The [Formula: see text]C result is in excellent agreement with the favored ground-state-to-ground-state transition according to the cluster model of Blendowske et al. We study nuclear structure properties of spin-1/2 heavy nuclei in the relativistic core-cluster model, that its cluster is [Formula: see text]C. According to this model for spin-1/2 heavy nuclei and for obtaining its wave function, we solve the Dirac equation with the new phenomenological potential by parametric Nikiforov–Uvarov method and then calculate the binding energy and charge radius.

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Data Perturbation Independent Diagnosis and Validation of Breast Cancer Subtypes Using Clustering and Patterns

Cancer Informatics ◽

10.1177/117693510600200006 ◽

2006 ◽

Vol 2 ◽

pp. 117693510600200 ◽

Cited By ~ 6

Author(s):

G. Alexe ◽

G.S. Dalgin ◽

R. Ramaswamy ◽

C. Delisi ◽

G. Bhanot

Keyword(s):

Breast Cancer ◽

Data Perturbation ◽

Luminal A ◽

Cancer Subtypes ◽

Luminal B ◽

Molecular Stratification ◽

Core Cluster ◽

Therapeutic Decisions ◽

Disease Subtypes

Molecular stratification of disease based on expression levels of sets of genes can help guide therapeutic decisions if such classifications can be shown to be stable against variations in sample source and data perturbation. Classifications inferred from one set of samples in one lab should be able to consistently stratify a different set of samples in another lab. We present a method for assessing such stability and apply it to the breast cancer (BCA) datasets of Sorlie et al. 2003 and Ma et al. 2003. We find that within the now commonly accepted BCA categories identified by Sorlie et al. Luminal A and Basal are robust, but Luminal B and ERBB2+ are not. In particular, 36% of the samples identified as Luminal B and 55% identified as ERBB2+ cannot be assigned an accurate category because the classification is sensitive to data perturbation. We identify a “core cluster” of samples for each category, and from these we determine “patterns” of gene expression that distinguish the core clusters from each other. We find that the best markers for Luminal A and Basal are (ESR1, LIV1, GATA-3) and (CCNE1, LAD1, KRT5), respectively. Pathways enriched in the patterns regulate apoptosis, tissue remodeling and the immune response. We use a different dataset (Ma et al. 2003) to test the accuracy with which samples can be allocated to the four disease subtypes. We find, as expected, that the classification of samples identified as Luminal A and Basal is robust but classification into the other two subtypes is not.

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