1,493 research outputs found
Quantum Isometries of the finite noncommutative geometry of the Standard Model
We compute the quantum isometry group of the finite noncommutative geometry F
describing the internal degrees of freedom in the Standard Model of particle
physics. We show that this provides genuine quantum symmetries of the spectral
triple corresponding to M x F where M is a compact spin manifold. We also prove
that the bosonic and fermionic part of the spectral action are preserved by
these symmetries.Comment: 29 pages, no figures v3: minor change
Ground states and excited states of hypernuclei in Relativistic Mean Field approach
Hypernuclei have been studied within the framework of Relativistic Mean Field
theory. The force FSU Gold has been extended to include hyperons. The effective
hyperon-nucleon and nucleon-nucleon interactions have been obtained by fitting
experimental energies in a number of hypernuclei over a wide range of mass.
Calculations successfully describe various features including hyperon
separation energy and single particle spectra of single-\Lambda hypernuclei
throughout the periodic table. We also extend this formalism to double-\Lambda
hypernuclei.Comment: 16 pages,3 figure
Target discovery focused approaches to overcome bottlenecks in the exploitation of antimycobacterial natural products
Tuberculosis is a major global health hazard. The search for new antimycobacterials has focused on such as screening combinational chemistry libraries or designing chemicals to target predefined pockets of essential bacterial proteins. The relative ineffectiveness of these has led to a reappraisal of natural products for new antimycobacterial drug leads. However, progress has been limited, we suggest through a failure in many cases to define the drug target and optimize the hits using this information. We highlight methods of target discovery needed to develop a drug into a candidate for clinical trials. We incorporate these into suggested analysis pipelines which could inform the research strategies to accelerate the development of new drug leads from natural products
FINITE ELEMENT SIMULATION OF LCF BEHAVIOUR OF SA 333 C-MN STEEL
Finite Element simulation to characterize the LCF behavior of Sa 333 C-Mn Steel is studied in this paper. Experiment and Finite Element simulation are done together. LCF parameters of the material are calibrated and tuned from the experimental results. Non linear version of Ziegler kinematic hardening material model is used to address the stable hysteresis cycles of the material. Cyclic hardening phenomenon is addressed by introducing cyclic hardening in the material model. The elastic plastic FE code ABAQUS is used for finite element simulation of LCF behavior. The plastic modulus formulation with zeigler kinematic hardening rule and exponential isotropic hardening rule has been used for simulation. Using the incremental plasticity theories the cyclic plastic stress-strain responses were analyzed and the results obtained from FE simulations have been compared with the experimental results at different strain amplitudes. Variation of cyclic yield stress with strain amplitudes has also been studied in this paper
Evaluation of Important Treatment Parameters in Supraphysiological Thermal Therapy of Human Liver Cancer HepG2 Cells
This study was aimed at simulating the effect of various treatment parameters like heating rate (HR), peak temperature (PT) and hold/total treatment time on the viability of human liver cancer HepG2 cells subjected to different thermal therapy conditions. The problem was approached by investigating the injury kinetics obtained using experimentally measured viability of the cells, heated to temperatures of 50–70°C for 0–9 min at HRs of 100, 200, 300 and 525°C min(−1). An empirical expression obtained between the activation energy (E) and HR was extended to obtain the E values over a broad range of HRs from 5 to 600°C min(−1) that mimic the actual conditions encountered in a typical thermal therapy protocol. Further, the effect of the HR (5–600°C min(−1)) and PT (50–85°C) on the cell survival was studied over a range of hold times. A significant drop in survival from 90% to 0% with the simultaneous increase in HR and PT was observed as the hold time increased from 0 to 5 min. For complete cell death, the hold time increased with the increase in the HR for a given PT, while the total time showed presence of minima for 60, 65 and 70°C at HRs of 50, 100 and 200°C min(−1), respectively
Distributed usability evaluation of the Pennsylvania Cancer Atlas
<p>Abstract</p> <p>Background</p> <p>The Pennsylvania Cancer Atlas (PA-CA) is an interactive online atlas to help policy-makers, program managers, and epidemiologists with tasks related to cancer prevention and control. The PA-CA includes maps, graphs, tables, that are dynamically linked to support data exploration and decision-making with spatio-temporal cancer data. Our Atlas development process follows a user-centered design approach. To assess the usability of the initial versions of the PA-CA, we developed and applied a novel strategy for soliciting user feedback through multiple distributed focus groups and surveys. Our process of acquiring user feedback leverages an online web application (e-Delphi). In this paper we describe the PA-CA, detail how we have adapted e-Delphi web application to support usability and utility evaluation of the PA-CA, and present the results of our evaluation.</p> <p>Results</p> <p>We report results from four sets of users. Each group provided structured individual and group assessments of the PA-CA as well as input on the kinds of users and applications for which it is best suited. Overall reactions to the PA-CA are quite positive. Participants did, however, provide a range of useful suggestions. Key suggestions focused on improving interaction functions, enhancing methods of temporal analysis, addressing data issues, and providing additional data displays and help functions. These suggestions were incorporated in each design and implementation iteration for the PA-CA and used to inform a set of web-atlas design principles.</p> <p>Conclusion</p> <p>For the Atlas, we find that a design that utilizes linked map, graph, and table views is understandable to and perceived to be useful by the target audience of cancer prevention and control professionals. However, it is clear that considerable variation in experience using maps and graphics exists and for those with less experience, integrated tutorials and help features are needed. In relation to our usability assessment strategy, we find that our distributed, web-based method for soliciting user input is generally effective. Advantages include the ability to gather information from users distributed in time and space and the relative anonymity of the participants while disadvantages include less control over when and how often participants provide input and challenges for obtaining rich input.</p
Generalized Holographic Cosmology
We consider general black hole solutions in five-dimensional spacetime in the
presence of a negative cosmological constant. We obtain a cosmological
evolution via the gravity/gauge theory duality (holography) by defining
appropriate boundary conditions on a four-dimensional boundary hypersurface.
The standard counterterms are shown to renormalize the bare parameters of the
system (the four-dimensional Newton's constant and cosmological constant). We
discuss the thermodynamics of cosmological evolution and present various
examples. The standard brane-world scenarios are shown to be special cases of
our holographic construction.Comment: 15 pages, 5 figure
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