Intrinsic charm in a matched general-mass scheme

The FONLL general-mass variable-flavour number scheme provides a framework for the matching of a calculation in which a heavy quark is treated as a massless parton to one in which the mass dependence is retained throughout. We describe how the usual formulation of FONLL can be extended in such a way that the heavy quark parton distribution functions are freely parameterized at some initial scale, rather than being generated entirely perturbatively. We specifically consider the case of deep-inelastic scattering, in view of applications to PDF determination, and the possible impact of a fitted charm quark distribution on $F_2^c$ is assessed.Comment: 16 pages, 5 figures. Final version, to be published in Physics Letters B. Typo in eq 13 corrected, minor clarifications adde

Comparison between Conventional and Non-Conventional Computer Methods to Define Antiknock Properties of Fuel Mixtures

Research Octane Number (RON) is one of the primary indicators for the determination of the resistance of gasoline fuels to autoignition. This parameter is usually determined with a test procedure involving a standardized engine that requires expensive hardware and time-consuming tests. In this work, a set of different methods with which to determine the RON of gasoline fuel surrogates is presented, considering only computer simulations, which allows to reduce both cost and time for the evaluation. A palette of 11 chemical species has been chosen as the basis for the surrogates’ database, which will be investigated in the work, allowing the representation of the complex chemical formulation of fuels in an easier way. A simplified zero-dimensional engine model of the standard variable compression ratio is used to provide pressure and temperature, then employed to calculate RON. This is done first by means of existing methods, and then by introducing new processes concerning a simplified chemical reactor built on kinetic schemes. Finally, these different methodologies are tested against a molar weighted sum of RONs of each chemical specie, allowing to have a criterion for comparison and evaluating their real prediction capabilities

Parton distributions: determining probabilities in a space of functions

We discuss the statistical properties of parton distributions within the framework of the NNPDF methodology. We present various tests of statistical consistency, in particular that the distribution of results does not depend on the underlying parametrization and that it behaves according to Bayes' theorem upon the addition of new data. We then study the dependence of results on consistent or inconsistent datasets and present tools to assess the consistency of new data. Finally we estimate the relative size of the PDF uncertainty due to data uncertainties, and that due to the need to infer a functional form from a finite set of data.Comment: 11 pages, 8 figures, presented by Stefano Forte at PHYSTAT 2011 (to be published in the proceedings

Minimally invasive management of a symptomatic case of Zinner’s syndrome: Laparoscopic seminal vesiculectomy and ipsilateral nephroureterectomy

Introduction: Zinner syndrome is a rare developmental anomaly of the Wolffian (mesonephric) duct which is characterized by a triad of obstruction of the ejaculatory duct, the ipsilateral seminal vesicle cyst, and the ipsilateral renal agenesis. Usually is totally asymptomatic, however it can also determine symptoms such as lower urinary tract symptoms, perineal pain, ejaculatory disorders such as painful ejaculation or hematospermia, and infertility. Case report: We present a case of a 51 years old men with a 3-year history of lower urinary tract symptoms, perineal pain, obstructed defecation, recurrent urinary tract infections and infertility. CT scan showed a voluminous cystic neoformation of the left seminal vesicle, hypoplasia of the left kidney and ipsilateral ureteronephrosis. The mass was removed using laparoscopic “en block” seminal vesiculectomy with associated ipsilateral nephroureterectomy. No post-operative complications occurred. At 2-month post-operative control the patient reported an improvement of urinary and rectal symptoms

Large primary leiomyosarcoma of the seminal vesicle: A case report and literature revision

Primary Leiomyosarcoma of the seminal vesicle is a very rare condition. We report a case of a 74-year-old man with a tumour detected by rectal symptoms with pelvic pain and dysuria at ultrasonography. Computed tomography and magnetic resonance imaging suggest an origin in the left seminal vesicle and did not show a clear cleavage plan with the rectum and a right hydroureteronephrosis was also present. A radical vesiculo-cystoprostatectomy with ileal conduit and bilateral pelvic lymphadenectomy was performed, a sigmoidectomy with end colostomy was performed also. Pathological examination showed a high grade (G3) leiomyosarcoma of the seminal vesicle

PENGARUH PENGGUNAAN METODE PEMBELAJARAN KOOPERATIF MAKE A MATCH TERHADAP

bstract: The purpose of this research is to looking for the influence of the using Cooperative learning type make a match to the student’s achievment. This research uses experiment method. The population is all students of 5 grade elementary school Wonogiri Wonogiri. The sample was selected using stratified cluster random sampling. The data resources focused in the achievement learning that gotten by pretest and posttest using questions test that had trough the research of validity, reability, difficulty index and ability of differentiation of question test. The pre-analytic of data are test of balance, normality test, and homogenity test. The technique of analytic of data that used to hipotesis test is t test. The result of the research can be concluded that there is a positif influence of using cooperative learning type make a match to the student’s achievement (t calculate > t table=56,691>2,00). Abstrak: Tujuan penelitian ini adalah untuk mengetahui pengaruh metode pembelajaran kooperatif make a match terhadap hasil belajar IPS. Penelitian ini menggunakan metode eksperimen. Populasi penelitian ini adalah siswa kelas 5 SDN Wonogiri, Wonogiri. Teknik pengambilan sampel yang digunakan adalah stratified cluster random sampling. Sumber data difokuskan pada proses belajar dan hasil belajar yang diperoleh melalui pretest dan posttest dengan instrument soal yang telah melalui uji validitas, reabilitas, indeks kesukaran dan daya pembeda soal. Uji prasyarat analisis menggunakan uji keseimbangan, uji normalitas, uji homogenitas. Sedangkan teknik analisis data sebagai uji hipotesis memakai uji t. Hasil dari penelitian ini dapat disimpulkan ada pengaruh yang positif signifikan model pembelajaran kooperatif Make a Match terhadap hasil belajar IPS (t hitung > t tabel =56,691>2,00). Kata Kunci: Pembelajaran Kooperatif, Make a Matc

On the Impact of NMC Data on NLO and NNLO Parton Distributions and Higgs Production at the Tevatron and the LHC

We discuss the impact of the treatment of NMC structure function data on parton distributions in the context of the NNPDF2.1 global PDF determination at NLO and NNLO. We show that the way these data are treated, and even their complete removal, has no effect on parton distributions at NLO, and at NNLO has an effect which is below one sigma. In particular, the Higgs production cross-section in the gluon fusion channel is very stable.Comment: 12 pages, 8 figures. Discussion extended to NNLO, and paper accordingly rewritten altogether. Several further small improvements, including new comparison plots to SLAC and NMC dat

Building physically-based models for assessing rainfall-induced shallow landslide hazard at the catchment scale : the case study of the Sorrento Peninsula (Italy)

The assessment of rainfall-induced shallow landslide hazard at the catchment scale poses significant challenge. Traditional empirical approaches for landslide hazard assessment often assume that conditions having caused failure in the past won't change in the future. This assumption may not hold in a climate change scenario. Physically-based models (PBMs) therefore represent the natural approach to include changing climate effects. PBMs would in principle require the combination of a 3-D mechanical and water-flow model. However, a full 3-D finite element model at the catchment scale, with relatively small elements required to capture the pore-water pressure gradients, would have a significant computational cost. For this reason, simplifications to the mechanical (i.e. infinite slope) and water-flow model (i.e. 1-D or hybrid 3-D) are introduced, often based on a-priori assumptions and not corroborated by experimental evidence. The paper presents a methodology to build a PBM in a bottom-up fashion based on geological surveys and geotechnical investigation. The PBM is initially set as simple as possible and then moved to a higher level of complexity if the model is not capable of simulating past landslide events. The approach is presented for the case study of Sorrento Peninsula and two main landslides events recorded during winter 1996-1997

Reweighting NNPDFs: the W lepton asymmetry

We present a method for incorporating the information contained in new datasets into an existing set of parton distribution functions without the need for refitting. The method involves reweighting the ensemble of parton densities through the computation of the chi-square to the new dataset. We explain how reweighting may be used to assess the impact of any new data or pseudodata on parton densities and thus on their predictions. We show that the method works by considering the addition of inclusive jet data to a DIS+DY fit, and comparing to the refitted distribution. We then use reweighting to determine the impact of recent high statistics lepton asymmetry data from the D0 experiment on the NNPDF2.0 parton set. We find that the D0 inclusive muon and electron data are perfectly compatible with the rest of the data included in the NNPDF2.0 analysis and impose additional constraints on the large-x d/u ratio. The more exclusive D0 electron datasets are however inconsistent both with the other datasets and among themselves, suggesting that here the experimental uncertainties have been underestimated.Comment: 36 pages, 22 figures: errors in Eqns.12,36,37 corrected and parts of Figs.1,6,10,13,15,19 replace