679 research outputs found

    Guided Unfoldings for Finding Loops in Standard Term Rewriting

    Full text link
    In this paper, we reconsider the unfolding-based technique that we have introduced previously for detecting loops in standard term rewriting. We improve it by guiding the unfolding process, using distinguished positions in the rewrite rules. This results in a depth-first computation of the unfoldings, whereas the original technique was breadth-first. We have implemented this new approach in our tool NTI and compared it to the previous one on a bunch of rewrite systems. The results we get are promising (better times, more successful proofs).Comment: Pre-proceedings paper presented at the 28th International Symposium on Logic-Based Program Synthesis and Transformation (LOPSTR 2018), Frankfurt am Main, Germany, 4-6 September 2018 (arXiv:1808.03326

    The 2mrad horizontal crossing angle IR layout for a TeV ILC

    Full text link
    The current status of the 2mrad crossing angle layout for the ILC is reviewed. The scheme developed in the UK and France is described and the performance discussed for a TeV machine. Secondly, the scheme developed at SLAC and BNL is then studied and modified for a TeV machine. We find that both schemes can handle the higher energy beam with modifications, and share many common features.Comment: The proceedings of the 2005 International Linear Collider Workshop, March 2005. 4 pages, 5 figure

    A New Beam Delivery System (BDS) for the TESLA Linear Collider

    Get PDF
    An overview of the proposed new BDS for the TESLA linear collider is presented. Several major changes have been incorporated since the publication of the TESLA Conceptual Design Report (CDR) [1]. The most notable of these modifications are: incorporation of the photonbasedpositron source upstream of the interaction point (IP), i.e. at the exit of the electron linac; a new concept for the collimation system, including integration of the emittance measurement section; an increase in the length of the final telescope, which, together with a new spent beam extraction line, allows for cleaner extraction of both the spent electron (positron) beam and the beamstrahlung photons

    Colchicine therapy in acute coronary syndrome patients acts on caspase-1 to suppress NLRP3 inflammasome monocyte activation

    Get PDF
    Inflammasome activation, with subsequent release of pro-inflammatory cytokines interleukin-1β (IL-1β) and IL-18, has recently been implicated in atherosclerosis-associated inflammation. This study aims to assess in acute coronary syndrome (ACS) patients (1) inflammasome activation in circulating monocytes and (2) whether short-term oral colchicine, a recognized anti-inflammatory agent that has been shown to be cardio-protective in clinical studies, might acutely suppress inflammasome-dependent inflammation. ACS patients (n=21) were randomized to oral colchicine (1 mg followed by 0.5 mg 1 h later) or no treatment, and compared with untreated healthy controls (n=9). Peripheral venous blood was sampled pre- (day 1) and 24 h post- (day 2) treatment. Monocytes were cultured and stimulated with ATP. Analysis of key inflammasome markers was performed by ELISA. IL-1β secretion increased by 580.4% (P<0.01) in ACS patients compared with controls but only with ATP stimulation. Untreated ACS patients secreted significantly higher levels of IL-18 compared with healthy controls independent of ATP stimulation (P<0.05). Colchicine treatment in ACS patients markedly reduced intracellular and secreted levels of IL-1β compared with pre-treatment levels (P<0.05 for both), as well as significantly reducing pro-caspase-1 mRNA levels by 57.7% and secreted caspase-1 protein levels by 30.2% compared with untreated patients (P<0.05 for both). Monocytes from ACS patients are ‘primed’ to secrete inflammasome-related cytokines and short-term colchicine acutely and markedly suppresses monocyte caspase-1 activity, thereby reducing monocyte secretion of IL-1β

    Efficient Set Sharing Using ZBDDs

    Get PDF
    Set sharing is an abstract domain in which each concrete object is represented by the set of local variables from which it might be reachable. It is a useful abstraction to detect parallelism opportunities, since it contains definite information about which variables do not share in memory, i.e., about when the memory regions reachable from those variables are disjoint. Set sharing is a more precise alternative to pair sharing, in which each domain element is a set of all pairs of local variables from which a common object may be reachable. However, the exponential complexity of some set sharing operations has limited its wider application. This work introduces an efficient implementation of the set sharing domain using Zero-suppressed Binary Decision Diagrams (ZBDDs). Because ZBDDs were designed to represent sets of combinations (i.e., sets of sets), they naturally represent elements of the set sharing domain. We show how to synthesize the operations needed in the set sharing transfer functions from basic ZBDD operations. For some of the operations, we devise custom ZBDD algorithms that perform better in practice. We also compare our implementation of the abstract domain with an efficient, compact, bit set-based alternative, and show that the ZBDD version scales better in terms of both memory usage and running time

    Predicting and understanding the stability of G-quadruplexes

    Get PDF
    Motivation: G-quadruplexes are stable four-stranded guanine-rich structures that can form in DNA and RNA. They are an important component of human telomeres and play a role in the regulation of transcription and translation. The biological significance of a G-quadruplex is crucially linked with its thermodynamic stability. Hence the prediction of G-quadruplex stability is of vital interest

    Evaluation of Luminosity Reduction in the ILC Head-on Scheme from Parasitic Collisions

    Get PDF
    online : http://cern.ch/AccelConf/p07/PAPERS/THPMN008.PDFInternational audienceAn interaction region with head-on collisions is being developed for the ILC as an alternative to the base line 14 mrad crossing angle design, motivated by simpler beam manipulations upstream of the interaction point (IP) and a more favourable configuration for the detector and physics analysis. The design of the post-collision beam line in this scheme involves however a number of technological challenges, one of which is the strength requirement for the electrostatic separators (ES) placed immediately after the final doublet to extract the spent beam. In this paper, we examine in detail the main mechanism behind this requirement, the multi-beam kink instability, which results from the long-range beam-beam forces at the parasitic crossings after the bunches have been extracted. Our analysis uses realistic bunch distributions, the Guinea-Pig program to treat beam-beam effects at the interaction point and the DIMAD program to track the disrupted beam distributions in the postcollision beam line

    Investigation of microstructure defects in EUROFER97 under He⁺/Fe³⁺ dual ion beam irradiation

    Get PDF
    Fusion like conditions for reduced activation ferritic/martensitic steels in the first wall are simulated with single Fe3+ and He+/Fe3+ dual ion beam irradiation of EUROFER97 at the Jannus laboratory, CEA Saclay, introducing a damage of 16 dpa and a helium content up to 260 appm. The samples are irradiated at temperatures of 330 °C, 400 °C and 500 °C. The quantitative determination of size distribution and density of dislocation loops is obtained using weak-beam dark-field imaging mode. Burgers vectors of a02〈111〉 are observed for the majority of dislocation loops at irradiation temperatures of 330 °C and 400 °C. At 500 °C no dislocation loops are found. The impact of single and dual ion beam irradiation on mechanical properties is determined by means of nanoindentation. An increase in nano-hardness of up to 35% due to irradiation was measured at samples irradiated at 400 °C. A kinetic rate model is applied for the description of nucleation and evolution of helium bubbles and compared with the experimental results. Evaluating the rate model with help of TEM-results for size and density of bubbles indicates the nucleation scheme as the main source for quantitative disagreement between the model and irradiation. Keywords: Radiation effects, Ion irradiation, Cluster dynamics, Fusion, Helium bubbles, RAFM steel

    Loops under Strategies ... Continued

    Full text link
    While there are many approaches for automatically proving termination of term rewrite systems, up to now there exist only few techniques to disprove their termination automatically. Almost all of these techniques try to find loops, where the existence of a loop implies non-termination of the rewrite system. However, most programming languages use specific evaluation strategies, whereas loop detection techniques usually do not take strategies into account. So even if a rewrite system has a loop, it may still be terminating under certain strategies. Therefore, our goal is to develop decision procedures which can determine whether a given loop is also a loop under the respective evaluation strategy. In earlier work, such procedures were presented for the strategies of innermost, outermost, and context-sensitive evaluation. In the current paper, we build upon this work and develop such decision procedures for important strategies like leftmost-innermost, leftmost-outermost, (max-)parallel-innermost, (max-)parallel-outermost, and forbidden patterns (which generalize innermost, outermost, and context-sensitive strategies). In this way, we obtain the first approach to disprove termination under these strategies automatically.Comment: In Proceedings IWS 2010, arXiv:1012.533
    corecore