Reggeon and pion contributions in semi-exclusive diffractive processes at HERA

A detailed analysis of semi-exclusive diffractive processes in e-p DIS at HERA, with the diffractive final states in the forward direction is presented. The contributions of the subleading f_2, \omega, a_2, \rho reggeons and the pion exchanges to the diffractive structure function with the forward proton or neutron are estimated. It is found that the (a_2,\rho) reggeons are entirely responsible for the forward neutron production at x_P < 10^{-3}. The \pi N production in the forward region is estimated using the Deck mechanism. The significance of this reaction for the processes measured at HERA, especially with the leading neutron, is discussed.Comment: Strongly revised version accepted for publication in Phys.Rev.D. Latex, 14 pages with 5 eps figures include

Powikłania leczenia operacyjnego złamań stawowych kości piętowej

Wstęp: Autorzy pracy prezentują zarejestrowane w materiale własnym powikłania leczenia operacyjnego złamań stawowych kości piętowej z wykorzystaniem różnego rodzaju materiałów zespalających. Materiały i metody: Analizowanymi technikami operacyjnymi były zespolenie Westhuesa oraz jego modyfikacja z dodatkową stabilizacją odłamów kostnych drutami Kirschnera, a także przezskórna stabilizacja sposobem Rąpały. Materiał badań obejmuje lata od 1990 do 2012 roku, a stanowi go 82 operowanych, w tym 68 mężczyzn (83%) i 14 kobiet (17%). Analizowane złamania kości piętowej klasyfi kowano w oparciu o podział Essex-Lopresti. Wyniki: Autorzy pracy zwracają uwagę, że najczęściej rejestrowanymi powikłaniami leczenia operacyjnego złamań stawowych kości piętowej w obserwacji wczesnej są powikłania zakrzepowo-zatorowe oraz miejscowy odczyn zapalny skóry w miejscu wprowadzenia do kości materiału zespalającego, a w obserwacji odległej zespół pozakrzepowy i zaburzenia algodystroficzne. Wnioski: Czynnikami sprzyjającymi występowaniu tych powikłań jest morfologia samego złamania, zespolenie odłamów kostnych nadmierną liczbą elementów materiału zespalającego oraz długotrwałe unieruchomienie kończyny operowanej.Introduction: The authors present complications following surgical treatment of intra-articular calcaneus fractures, in regards to the surgical technique employed, based on their own clinical material. Materials and methods: The techniques analyzed included the Westhues’ technique and its modifi cation with additional bone stabilization by Kirschner wires and the percutaneous stabilization by Rapala. The research material covered the years from 1990 to 2012 and consists of 82 operated patients - 68 men (83%) and 14 women (17%). Analyzed calcaneus fractures were divided using the Essex-Lopresti classifi cation. Results: The authors of the article indicate that the most frequently registered complications of surgical treatment of intra-articular calcaneus fractures in early observation were thromboembolic complications and local infl ammatory reactions of the skin at the point of incision and placing the stabilizing material. During the long-term follow-up, the post-thrombotic syndrome and algodystrophic disorders were the most common. Conclusions: Factors contributing to the occurrence of the complications registered were fracture morphology, fixation of bone fragments by an excessive number of stabilizing materials and prolonged immobilization of the operated limb

Czynnościowe wyniki odległe oraz uwarunkowania fizjoterapeutyczne leczenia operacyjnego złamań stawowych kości piętowej

Wstęp: Autorzy pracy prezentują obserwacje własne z zakresu operacyjnego leczenia złamań stawowych kości piętowej z zastosowaniem przezskórnych zespoleń małoinwazyjnych w skojarzeniu ze zunifikowanym autorskim programem fizjoterapii. Materiały i metody: Są nimi zespolenie Westhuesa oraz jego modyfikacja z dodatkową stabilizacją odłamów kostnych drutami Kirschnera, a także przezskórna stabilizacja sposobem Rąpały. Materiał badań obejmuje lata 1990- 2012, a stanowi go 82 operowanych, w tym 68 mężczyzn (83%) i 14 kobiet (17%). Analizowane złamania kości piętowej klasyfikowano stosując podział Essex-Lopresti, a do oceny wyników czynnościowych w obserwacji odległej posłużono się kryteriami Creighton-Nebraska. Wyniki: Wśród mężczyzn z rozpoznanym złamaniem typu "języka", u których zastosowano zespolenie odłamów kostnych sposobem Westhuesa, wyniki dobre odnotowano u 12 operowanych, czyli u 17,6%, oraz wyniki zadowalające u pozostałych 7, czyli u 10,3%. W grupie kobiet leczonych z powodu złamań stawowych kości piętowej typu „języka” sposobem Westhuesa odnotowano wyniki dobre u 2 operowanych, czyli u 14,3%, oraz wynik zły u jednej z nich, co stanowi 7,1%. Wnioski: Na podstawie analizy zebranego materiału autorzy pracy skłaniają się do stwierdzenia, że wymienione zespolenia odłamów kostnych są jedynie z pozoru małoinwazyjne, a powikłane zwłaszcza powikłaniami skojarzonymi u większości operowanych prowadzą w obserwacji odległej do niekorzystnych wyników czynnościowych.Introduction: The authors present their own observations of the surgical treatment of articular calcaneal fractures using a minimally invasive percutaneous fixation in combination with the unifi ed self-developed physiotherapy program. Material and methods: The analyzed techniques include the Westhues’ technique and its modifi cation with additional stabilization of the bone fragments with Kirschner wires, as well as transdermal stabilization by Rąpała. The research material comprises 82 patients with intraarticular fractures - 68 men (83%) and 14 women (17%) treated surgically between 1990 and 2012. The analyzed calcaneus fractures were divided by Essex-Lopresti scale and evaluation of functional outcome at follow-up was based on the Creighton-Nebraska criteria. Results: Men with the "tongue type" fracture treated using the Westhues’ technique had good functional outcomes in 12 cases (17.6%) and acceptable in 7 cases (10.3%). Women with the “tongue type” fracture treated using the Westhues’ technique had good functional outcomes in 2 cases (14.3%) and in one case, poor (7.1%). Conclusions: After analysis of the material, the authors claim that minimally invasive techniques are not really minimally invasive, taking the observed complications into consideration in most of the patients, which lead to the poor functional outcome at long term follow-ups

Do investors see through mistakes in reported earnings?

This study investigates whether investors see through materially misstated earnings, and whether they anticipate earnings restatements. For firms that restate at least one annual report, we find that investors are misled by mistakes in reported earnings at the time of initial earnings announcements. Investors react positively to the component of the favorable earnings surprise that will subsequently be restated, and attach the same valuation to it as to the true earnings surprise. We also find that investors anticipate the subsequent downward restatements and start marking stock prices down several months before a restatement announcement, so that the full impact of a restatement is about three times as large as the initial announcement effect. Overall our findings indicate that although investors anticipate restatements several months before its announcement, they are misled by misstated earnings for several years and therefore would benefit from better quality of financial information

EdgeAISim: A Toolkit for Simulation and Modelling of AI Models in Edge Computing Environments

To meet next-generation Internet of Things (IoT) application demands, edge computing moves processing power and storage closer to the network edge to minimize latency and bandwidth utilization. Edge computing is becoming increasingly popular as a result of these benefits, but it comes with challenges such as managing resources efficiently. Researchers are utilising Artificial Intelligence (AI) models to solve the challenge of resource management in edge computing systems. However, existing simulation tools are only concerned with typical resource management policies, not the adoption and implementation of AI models for resource management, especially. Consequently, researchers continue to face significant challenges, making it hard and time-consuming to use AI models when designing novel resource management policies for edge computing with existing simulation tools. To overcome these issues, we propose a lightweight Python-based toolkit called EdgeAISim for the simulation and modelling of AI models for designing resource management policies in edge computing environments. In EdgeAISim, we extended the basic components of the EdgeSimPy framework and developed new AI-based simulation models for task scheduling, energy management, service migration, network flow scheduling, and mobility support for edge computing environments. In EdgeAISim, we have utilized advanced AI models such as Multi-Armed Bandit with Upper Confidence Bound, Deep Q-Networks, Deep Q-Networks with Graphical Neural Network, and Actor-Critic Network to optimize power usage while efficiently managing task migration within the edge computing environment. The performance of these proposed models of EdgeAISim is compared with the baseline, which uses a worst-fit algorithm-based resource management policy in different settings. Experimental results indicate that EdgeAISim exhibits a substantial reduction in power consumption, highlighting the compelling success of power optimization strategies in EdgeAISim. The development of EdgeAISim represents a promising step towards sustainable edge computing, providing eco-friendly and energy-efficient solutions that facilitate efficient task management in edge environments for different large-scale scenarios

A simple shower and matching algorithm

We present a simple formalism for parton-shower Markov chains. As a first step towards more complete uncertainty bands, we incorporate a comprehensive exploration of the ambiguities inherent in such calculations. To reduce this uncertainty, we then introduce a matching formalism which allows a generated event sample to simultaneously reproduce any infrared safe distribution calculated at leading or next-to-leading order in perturbation theory, up to sub-leading corrections. To enable a more universal definition of perturbative calculations, we also propose a more general definition of the hadronization cutoff. Finally, we present an implementation of some of these ideas for final-state gluon showers, in a code dubbed VINCIA.Comment: 32 pages, 6 figure

The colour dipole approach to small-x processes

We explain why it is possible to formulate a wide variety of high energy (small-x) photon-proton processes in terms of a universal dipole cross section and compare and contrast various parameterizations of this function that exist in the literature.Comment: 6 pages, latex, 2 figures. Contribution to Durham Collider Workshop (Sept 99) proceeding

Constrained MC for QCD evolution with rapidity ordering and minimum kT

With the imminent start of LHC experiments, development of phenomenological tools, and in particular the Monte Carlo programs and algorithms, becomes urgent. A new algorithm for the generation of a parton shower initiated by the single initial hadron beam is presented. The new algorithm is of the class of the so called ``constrained MC'' type algorithm (an alternative to the backward evolution MC algorithm), in which the energy and the type of the parton at the end of the parton shower are constrained (predefined). The complete kinematics configurations with explicitly constructed four momenta are generated and tested. Evolution time is identical with rapidity and minimum transverse momentum is used as an infrared cut-off. All terms of the leading-logarithmic approximation in the DGLAP evolution are properly accounted for. In addition, the essential improvements towards the so-called CCFM/BFKL models are also properly implemented. The resulting parton distributions are cross-checked up to the 0.1% precision level with the help of a multitude of comparisons with other MC and non-MC programs. We regard these tests as an important asset to be exploited at the time when the presented MC will enter as a building block in a larger MC program for W/Z production process at LHC.Comment: Submitted to Computer Physics Communication

Markovian MC simulation of QCD evolution at NLO level with minimum k_T

We present two Monte Carlo algorithms of the Markovian type which solve the modified QCD evolution equations at the NLO level. The modifications with respect to the standard DGLAP evolution concern the argument of the strong coupling constant alpha_S. We analyze the z - dependent argument and then the k_T - dependent one. The evolution time variable is identified with the rapidity. The two algorithms are tested to the 0.05% precision level. We find that the NLO corrections in the evolution of parton momentum distributions with k_T - dependent coupling constant are of the order of 10 to 20%, and in a small x region even up to 30%, with respect to the LO contributions.Comment: 32 pages, 9 pdf figure

Investigating the high energy QCD approaches for prompt photon production at the LHC

We investigate the rapidity and transverse momentum distributions of the prompt photon production at the CERN LHC energies considering the current perturbative QCD approaches for this scattering process. Namely, we compare the predictions from the usual NLO pQCD calculations to the the color dipole formalism, using distinct dipole cross sections. Special attention is paid to parton saturation models at high energies, which are expected to be important at the forward rapidities in pp collisions at the LHC.Comment: Contribution to the proceedings of the 3rd International Conference on Hard and Electro-Magnetic Probes of High-Energy Nuclear Collisions (Hard Probes 2008), 8-14 June 2008, Illa da Toxa (Galicia-Spain). Talk presented by M.V.T. Machad