scholarly journals OpenLoops 2

Author(s):  
Federico Buccioni ◽  
Jean-Nicolas Lang ◽  
Jonas M. Lindert ◽  
Philipp Maierhöfer ◽  
Stefano Pozzorini ◽  
...  

Abstract We present the new version of OpenLoops, an automated generator of tree and one-loop scattering amplitudes based on the open-loop recursion. One main novelty of OpenLoops 2 is the extension of the original algorithm from NLO QCD to the full Standard Model, including electroweak (EW) corrections from gauge, Higgs and Yukawa interactions. In this context, among several new features, we discuss the systematic bookkeeping of QCD–EW interferences, a flexible implementation of the complex-mass scheme for processes with on-shell and off-shell unstable particles, a special treatment of on-shell and off-shell external photons, and efficient scale variations. The other main novelty is the implementation of the recently proposed on-the-fly reduction algorithm, which supersedes the usage of external reduction libraries for the calculation of tree–loop interferences. This new algorithm is equipped with an automated system that avoids Gram-determinant instabilities through analytic methods in combination with a new hybrid-precision approach based on a highly targeted usage of quadruple precision with minimal CPU overhead. The resulting significant speed and stability improvements are especially relevant for challenging NLO multi-leg calculations and for NNLO applications.

2016 ◽  
Vol 28 (04) ◽  
pp. 1650026
Author(s):  
K. Rouhollahi ◽  
M. Emadi Andani ◽  
S. M. Karbassi ◽  
M. Mojiri

Deep brain stimulation (DBS) is one of the most effective neurosurgical procedures to reduce Parkinsons tremor. The conventional method of DBS is open loop stimulation of one area of basal ganglia (BG). On the other hand, existing feedback causes the reduction of additional stimulatory signal delivered to the brain which results in the reduction of the side effects caused by the excessive stimulation intensity. Actually, the stimulatory intensity of the controllers is reduced proportionally by the reduction of hands tremor, which is in fact the intended rehabilitation of the disease. The meaningful objective of this study is to design an architecture of controllers to decrease three criteria. The first one is the hand’s tremor, the second one is the level of delivered stimulation signal to brain in disease condition and the third one is the ratio of the level of delivered stimulation signal in health condition to disease condition. In order to achieve these objectives, a new architecture of a closed loop control system to stimulate two areas of BG at the same time is presented. One area (STN: subthalamic nucleus) is stimulated with a state feedback (SF) controller (pole placement method) and the other area (GPi: globus pallidus internal) is stimulated with a partial state feedback controller (PSFC). Considering these criteria, the results illustrate that stimulating two areas leads to a suitable performance. Simulation results show that the PSF and SF controllers are robust enough to the variations of the system parameters. Moreover, we are able to estimate the parameters of BG model in real time; it is a valuable method to update the time variable parameters of this model.


Author(s):  
Niles Eldredge

My intention in this and the following chapter is simply to clarify what a few of the better known architects of the synthesis actually had to say about how the entire spectrum of genes through phyla really fits together. I have chosen books rather than a potpourri of articles from the (possibly) more “technical” scientific literature, for precisely this reason: it is in the books that we find the coherent, integrated statements. And each of the four books singled out for particularly close analysis—Genetics and the Origin of Species (Dobzhansky 1937a); Genetics and the Origin of Species second edition (Dobzhansky 1941); Systematics and the Origin of Species (Mayr 1942); and Tempo and Mode in Evolution (Simpson 1944)—is a truly coherent, though not necessarily smoothly linear, argument. In each, some parts seem more vital to the flow of argument than others, but it is clear to the reader from the outset that each is a complete book and not a disjointed melange of unrelated ideas. Then, too, the contents of each author’s papers are to a great extent reflected in the respective books. It is apparent, for example, that Dobzhansky was publishing a variety of papers in the 1930s (many were in his “Genetics of Natural Populations” series republished in a single volume in 1981 by Lewontin et al.) which he liberally drew upon for illustrative material in Genetics and the Origin of Species. The other sorts of papers Dobzhansky was publishing seem to be byproducts of his thinking and research for the various editions of his book. Examples are his papers on species definitions (1935) and isolating mechanisms (1937b) and his theory of the origin of isolating mechanisms by reinforcement (1940). The choice of the four particular books for special treatment in this volume needs further comment. I have omitted such nonconformist works as Robson and Richards (1936), Willis (1940), and Goldschmidt (1940) precisely because they have been almost universally considered as falling outside the limits of the synthesis. The main historical effect of such books (especially Goldschmidt’s) seems to have been as irritants.


Author(s):  
Elisa Benetti ◽  
Gianluca Mazzini

Computer science and telecommunications are increasingly important in society and this leads also public administrations to take advantage of ICT, in order to communicate with citizens in a more rapid and simpler way than the complex and paper-based bureaucracy of the past. While on the one hand the use of these technologies responds to the duty of any public institution to involve the largest number of addressees, on the other hand, society must also consider the limitations of these technologies. Firstly not everybody is so familiar in their use. Moreover, the digital administration thus becomes virtual, accessible only through technological devices and not present in a physical location, and is therefore essential to ensure full coverage of the territory, which is currently not always possible. The main novelty of this paper is the implementation of an automated system capable of adapting different types of government services to multiple communication media. The joint exploitation of multiple technologies allows to use the strengths of one of them when are found the limits of another, making this multichannel modality the solution to the requirement of ICT in public administration.


Author(s):  
Roberto Strada ◽  
Alberto Oldani

Electro-hydraulic elevators are widely used systems, especially in low level buildings, due to their very good ratio between power generation and dynamic response. Generally, the goal of an elevator system is just to reach the floor with a precision enough to be comfortable for the passengers, without the need to follow a specific law of motion; hence an open-loop control system could be enough. Otherwise such a kind of solution reduces the number of components, bringing down the costs of production. On the other hand a complete knowledge of the mechanical system’s behaviour is required. In this work we deal with the analysis of the behaviour of a commercial hydraulic elevator driven by an open loop control that monitors the downstream pressure of the proportional valve supplying the cylinder. At the end of the paper, a closed loop solution based on the pressure measurement and on the motion time is proposed.


2017 ◽  
Vol 35 (15_suppl) ◽  
pp. e17541-e17541
Author(s):  
Naser Al-Rajhi ◽  
Hussein Soudy ◽  
Shamayel Mohammed ◽  
Hatem Khoja ◽  
Hazem Ghebeh

e17541 Background: The prevalence of Nasopharyngeal Carcinoma (NPC) is higher in Saudi Arabia compared to western countries. Genetic susceptibility and/or environmental factors (like infection with Epstein-Barr virus) contribute to the development of this tumor. There is a lack of information on the expression of markers related to the immune response in Saudi NPC patients. Methods: Here we report on profiling of two cohorts of NPC cases from patients treated at King Faisal specialist hospital & Research cneter (KFSH&RC) using the most relevant immune markers. The first cohort included 54 patients with local NPC while the other cohort included 25 cases of metastatic NPC at presentation. Immunostaining was done using Ventana benchmark fully automated system. Two anatomical pathologists (SM & HK) scored the NPC cases for CD3+ infiltrating lymphocytes (TIL), and their sub-fractions co-staining for CD8, FOXP3 and/or PD-1. On the other hand, PDL1 expression was assessed on tumor cells. Statistical analysis was done using JUMP Pro 13 software. Results: There was an induction of membranous PDL1 expression on tumor cells of 70 and 64% in local and metastatic cases respectively. Interestingly, there was a significant number of cases with cytoplasmic expression of PDL1 (46% of local and 36% metastatic cases) in addition to the membranous expression. PD-1 was over-expressed (on ≥ 10% of TIL) in 52% and 68% of local and metastatic cases respectively. FOXP3+ T-cells were abundant in the tumor tissues as 78% of cases had ≥10% of their infiltrating CD3+ T-cells co-staining for nuclear FOXP3. Finally, CD8 were an abundant fraction of total CD3+ infiltrating T-cells in more than 60% and 78% of Local and metastatic cohorts respectively. Correlation of the above studied immune markers with patients clinical outcome shows statistically significant correlation (p = 0.008) between low CD3+ T-cell infiltration in tumor tissues at diagnosis and the relapse of the disease. Conclusions: PDL1 is upregulated, FOXP3+ T-regs are abundant, only the low intensity of CD3+ lymphocytes could predict for higher chances of relapse. These preliminary profiling data provide the basis for future immunotherapy trials for NPC in KFSH&RC


Significance The Kremlin is saying nothing, but seems unlikely to approve an extension and has not initiated the legislation needed for this. Ending the treaty will annul Tatarstan's claim to unique political and economic sovereignty, although its real autonomy has been greatly eroded over the last decade. Impacts Abandoning the Tatarstan treaty may signal a new Kremlin impetus for greater centralisation and a unitary state. Tatarstan will retain its position as a wealthy donor region. Regional leaders will resent the special treatment given to Crimea and Chechnya at the other end of the economic spectrum.


2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Vladimir Kuksa

The propagators of unstable particles are considered in framework of the convolution representation. Spectral function is found for a special case when the propagator of scalar unstable particle has Breit-Wigner form. The expressions for the dressed propagators of unstable vector and spinor fields are derived in an analytical way for this case. We obtain the propagators in modified Breit-Wigner forms which correspond to the complex-mass definition.


2007 ◽  
Vol 3 (S246) ◽  
pp. 251-255
Author(s):  
A. Tanikawa ◽  
T. Fukushige

AbstractWe performed N-body simulations of star clusters with primordial binaries using a new code, GORILLA. It is based on Makino and Aarseth (1992)'s integration scheme on GRAPE, and includes a special treatment for relatively isolated binaries. Using the new code, we investigated effects of hardness of primordial binaries on whole evolution of the clusters. We simulated seven N=16384 equal-mass clusters containing 10% (in mass) primordial binaries whose binding energies are 1, 3, 10, 30, 100, 300, and 1000kT, respectively. Additionally, we also simulated a cluster without primordial binaries and that in which all binaries are replaced by stars with double mass, as references of soft and hard limits, respectively. We found that, in both soft (≤ 3kT) and hard (≥ 1000kT) limits, clusters experiences deep core collapse and shows gravothermal oscillations. On the other hands, in the intermediate hardness (10-300kT), the core collapses halt halfway due an energy releases of the primordial binaries.


2012 ◽  
Vol 102 (3) ◽  
pp. 269-276 ◽  
Author(s):  
Sergio D. Hilário ◽  
Márcia de F. Ribeiro ◽  
Vera L. Imperatriz-Fonseca

Flight activity of foragers of four colonies of Plebeia remota (Holmberg, 1903) was registered from December 1998 to December 1999, using an automated system (photocells and PLC system). The colonies originated from two different regions: Cunha, state of São Paulo, and Prudentópolis, state of Paraná, Brazil. Flight activity was influenced by different climatic factors in each season. In the summer, the intensity of the correlations between flight activity and climatic factors was smaller than in the other seasons. During the autumn and winter, solar radiation was the factor that most influenced flight activity, while in the spring, this activity was influenced mainly by temperature. Except in the summer, the various climatic factors similarly influenced flight activity of all of the colonies. Flight activity was not affected by geographic origin of the colonies. Information concerning seasonal differences in flight activity of P. remota will be useful for prediction of geographic distribution scenarios under climatic changes.


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