Massively Parallel Computing and the Search for Jets and Black Holes at the LHC

Massively parallel computing at the LHC could be the next leap necessary to reach an era of new discoveries at the LHC after the Higgs discovery. Scientific computing is a critical component of the LHC experiment, including operation, trigger, LHC computing GRID, simulation, and analysis. One way to improve the physics reach of the LHC is to take advantage of the flexibility of the trigger system by integrating coprocessors based on Graphics Processing Units (GPUs) or the Many Integrated Core (MIC) architecture into its server farm. This cutting edge technology provides not only the means to accelerate existing algorithms, but also the opportunity to develop new algorithms that select events in the trigger that previously would have evaded detection. In this article we describe new algorithms that would allow to select in the trigger new topological signatures that include non-prompt jet and black hole--like objects in the silicon tracker.Comment: 15 pages, 11 figures, submitted to NIM

First Evaluation of the CPU, GPGPU and MIC Architectures for Real Time Particle Tracking based on Hough Transform at the LHC

Recent innovations focused around {\em parallel} processing, either through systems containing multiple processors or processors containing multiple cores, hold great promise for enhancing the performance of the trigger at the LHC and extending its physics program. The flexibility of the CMS/ATLAS trigger system allows for easy integration of computational accelerators, such as NVIDIA's Tesla Graphics Processing Unit (GPU) or Intel's \xphi, in the High Level Trigger. These accelerators have the potential to provide faster or more energy efficient event selection, thus opening up possibilities for new complex triggers that were not previously feasible. At the same time, it is crucial to explore the performance limits achievable on the latest generation multicore CPUs with the use of the best software optimization methods. In this article, a new tracking algorithm based on the Hough transform will be evaluated for the first time on a multi-core Intel Xeon E5-2697v2 CPU, an NVIDIA Tesla K20c GPU, and an Intel \xphi\ 7120 coprocessor. Preliminary time performance will be presented.Comment: 13 pages, 4 figures, Accepted to JINS

British American Tobacco and the "insidious impact of illicit trade'' in cigarettes across Africa

Objectives: To provide an overview of the complicity of British American Tobacco (BAT) in the illicit trade of cigarettes across the African continent in terms of rationale, supply routes and scale.Methods: Analysis of internal BAT documents and industry publications.Results: BAT has relied on illegal channels to supply markets across Africa since the 1980s. Available documents suggest smuggling has been an important component of BAT's market entry strategy in order to gain leverage in negotiating with governments for tax concessions, compete with other transnational tobacco companies, circumvent local import restrictions and unstable political and economic conditions and gain a market presence. BAT worked through distributors and local agents to exploit weak government capacity to gain substantial market share in major countries.Conclusions: Documents demonstrate that the complicity of BAT in cigarette smuggling extends to Africa, which includes many of the poorest countries in the world. This is in direct conflict with offers by the company to contribute to stronger international cooperation to tackle the illicit tobacco trade.</p

Remodeler Catalyzed Nucleosome Repositioning: Influence of Structure and Stability

The packaging of the eukaryotic genome into chromatin regulates the storage of genetic information, including the access of the cell’s DNA metabolism machinery. Indeed, since the processes of DNA replication, translation, and repair require access to the underlying DNA, several mechanisms, both active and passive, have evolved by which chromatin structure can be regulated and modified. One mechanism relies upon the function of chromatin remodeling enzymes which couple the free energy obtained from the binding and hydrolysis of ATP to the mechanical work of repositioning and rearranging nucleosomes. Here, we review recent work on the nucleosome mobilization activity of this essential family of molecular machines

Structural Relationships between the Exshaw Thrust and Heart Mountain syncline, Exshaw, Alberta

Displacement transfer between faults and folds has been extensively documented in the Rocky Mountains as an explanation for structural variability along strike producing seemingly similar overall shortenings. A series of subparallel imbricate thrusts and an associated syncline in the Southern Canadian Front ranges at Heart Mountain has been mapped at a scale of 1:16,667. Megascopic, mesoscopic and microscopic evidence supports the contention that the folding observed at Heart Mountain occurred synchronously with thrusting as the result of displacement transfer from the adjacent thrust. Numerical dynamic analyses (NDA) suggest that twinning of calcite grains occurred very early in the deformational history in response to a regional stress field orientation of 246/03, 340/02, and 159/84 for o 1, o2 , and 03 respectively in the Exshaw plate. Megascopic and mesoscopic fabrics indicate similar results. Ambiguous NDA results for the Heart Mountain Syncline are explained using neutral surface folding theories rather than flexural slip theories generally proposed for folding within the Front Ranges. Neutral surface folds are consistent with the deformational model (displacement transfer) proposed. An orthogonal fracture system is pervasive throughout the thesis area. Observations indicate that fractures are oriented parallel and perpendicular to the strike of the Rocky Mountains. Their development is inferred to have taken place in the same regional stress field thought to be responsible for twinning, with fracture opening occurring after the relaxation of tectonic stresses and the removal of substantial amounts of overburden. ThesisBachelor of Science (BSc

A partitioned model order reduction approach to rationalise computational expenses in multiscale fracture mechanics

We propose in this paper an adaptive reduced order modelling technique based on domain partitioning for parametric problems of fracture. We show that coupling domain decomposition and projection-based model order reduction permits to focus the numerical effort where it is most needed: around the zones where damage propagates. No \textit{a priori} knowledge of the damage pattern is required, the extraction of the corresponding spatial regions being based solely on algebra. The efficiency of the proposed approach is demonstrated numerically with an example relevant to engineering fracture.Comment: Submitted for publication in CMAM

A computationally efficient reduced order model to generate multi-parameter fluid-thermal databases

A reduced order model (ROM) is proposed to generate multi-parameter databases of some fluid-thermal problems, using a combination of proper orthogonal decomposition, a gradient-like method, and a continuation method. The resulting ROM greatly reduces the CPU time required by slower methods based on genetic algorithm formulations. As a byproduct, the number of required snapshots is also reduced, which yields an additional improvement of the computational efficiency. The work presented in this article aims to facilitate the use of ROMs in industrial environments, in which time is a very important asset. The methodology is illustrated with the non-isothermal flow past a backward-facing step in the laminar regime, which is a representative problem, related to the engineering design of micro-heat sinks

Student gender modulates the intersection of calculus proficiency and calculus self-efficacy in an introductory electricity and magnetism course

We assessed changes in calculus proficiency and calculus self-efficacy in a second semester course of introductory physics focused on electricity and magnetism. While all students demonstrated an increase in calculus proficiency, including a possible improvement in calculus transfer to physics, women displayed larger gains than men. Conversely, men showed larger gains in calculus self-efficacy. When combined, these data suggest that student identity modulates the correlation between a student's calculus abilities and their perception or self-evaluation of those abilities. These data highlight a potential contributing factor to gender-related differences in physics self-efficacy as well as the complexity of addressing those differences