Open charm meson production at LHC

We discuss charm production at the LHC. The production of single $c \bar c$ pairs is calculated in the $k_t$-factorization approach. We use Kimber-Martin-Ryskin unintegrated gluon distributions in the proton. The hadronization is included with the help of Peterson fragmentation functions. Transverse momentum and pseudorapidity distributions of charmed mesons are presented and compared to recent results of the ALICE, LHCb and ATLAS collaborations. Furthermore we discuss production of two pairs of $c \bar c$ within a simple formalism of double-parton scattering (DPS). Surprisingly large cross sections, comparable to single-parton scattering (SPS), are predicted for LHC energies. We discuss perspectives how to identify the double scattering contribution. We predict much larger cross section for large rapidity distance between charm quarks from different hard parton scatterings compared to single scattering.Comment: 5 pages, 4 figures, talk given by R. Maciula at the MESON2012 - 12th International Workshop on Meson Production, Properties and Interaction, 31 May - 5 June 2012, Krakow, Polan

D-meson decay constants and a check of factorization in non-leptonic B-decays

We compute the vector meson decay constants fD*, fDs* from the simulation of twisted mass QCD on the lattice with Nf = 2 dynamical quarks. When combining their values with the pseudoscalar D(s)-meson decay constants, we were able (i) to show that the heavy quark spin symmetry breaking effects with the charm quark are large, fDs*/fDs = 1.26(3), and (ii) to check the factorization approximation in a few specific B-meson non-leptonic decay modes. Besides our main results, fD* = 278 \pm 13 \pm 10 MeV, and fDs* = 311 \pm 9 MeV, other phenomenologically interesting results of this paper are: fDs*/fD* = 1.16 \pm 0.02 \pm 0.06, fDs*/fD = 1.46 \pm 0.05 \pm 0.06, and fDs/fD* = 0.89 \pm 0.02 \pm 0.03. Finally, we correct the value for B(B0 \rightarrow D+ pi-) quoted by PDG, and find B(B0 \rightarrow D+ pi-) = (7.8 \pm 1.4) \times 10-7. Alternatively, by using the ratios discussed in this paper, we obtain B(B0 \rightarrow D+ pi-) = (8.3 \pm 1.0 \pm 0.8)\times10-7.Comment: 16 pages, 4 eps figure

The photon PDF from high-mass Drell Yan data at the LHC

Achieving the highest precision for theoretical predictions at the LHC requires the calculation of hard-scattering cross-sections that include perturbative QCD corrections up to (N)NNLO and electroweak (EW) corrections up to NLO. Parton distribution functions (PDFs) need to be provided with matching accuracy, which in the case of QED effects involves introducing the photon parton distribution of the proton, $x\gamma(x,Q^2)$. In this work a determination of the photon PDF from fits to recent ATLAS measurements of high-mass Drell-Yan dilepton production at $\sqrt{s}=8$ TeV is presented. This analysis is based on the xFitter framework, and has required improvements both in the APFEL program, to account for NLO QED effects, and in the aMCfast interface to account for the photon-initiated contributions in the EW calculations within MadGraph5_aMC@NLO. The results are compared with other recent QED fits and determinations of the photon PDF, consistent results are found

Co-targeting PIM and PI3K/mTOR using multikinase inhibitor AUM302 and a combination of AZD-1208 and BEZ235 in prostate cancer

PIM and PI3K/mTOR pathways are often dysregulated in prostate cancer, and may lead to decreased survival, increased metastasis and invasion. The pathways are heavily interconnected and act on a variety of common efectors that can lead to the development of resistance to drug inhibitors. Most current treatments exhibit issues with toxicity and resistance. We investigated the novel multikinase PIM/PI3K/mTOR inhibitor, AUM302, versus a combination of the PIM inhibitor, AZD-1208, and the PI3K/mTOR inhibitor BEZ235 (Dactolisib) to determine their impact on mRNA and phosphoprotein expression, as well as their functional efcacy. We have determined that around 20% of prostate cancer patients overexpress the direct targets of these drugs, and this cohort are more likely to have a high Gleason grade tumour (≥Gleason 8). A co-targeted inhibition approach ofered broader inhibition of genes and phosphoproteins in the PI3K/mTOR pathway, when compared to single kinase inhibition. The preclinical inhibitor AUM302, used at a lower dose, elicited a comparable or superior functional outcome compared with combined AZD-1208 +BEZ235, which have been investigated in clinical trials, and could help to reduce treatment toxicity in future trials. We believe that a co-targeting approach is a viable therapeutic strategy that should be developed further in pre-clinical studies

Risk Factors for Serious Bacterial Infection in Febrile Young Infants in a Community Referral Hospital

Differentiation of serious bacterial infection (SBI) from self-limiting viral illness in febrile infants younger than three months is a significant challenge for clinicians. We aimed to assess the risk factors for SBI in febrile infants. Data were obtained from 221 infants younger than three months who visited a single community referral hospital for fever and underwent a complete sepsis workup between August 2003 and July 2006. The causes of fever were febrile illness without a documented cause (FISDC, 65%), urinary tract infection (UTI, 12%), aseptic meningitis (12%), bacteremia (4%), bacterial meningitis (2%). Cerebrospinal fluid enterovirus polymerase chain reaction was positive in 28% of FISDC and 48% of aseptic meningitis cases. When UTI was excluded, the risk factors for SBI were 1) C-reactive protein (CRP) level of ≥1.87 mg/dL and 2) fevers of ≥38.9℃. The specificity and negative predictive values of risk factors 1) and 2) for the diagnosis of SBI were 94% and 95%, respectively. We concluded that enteroviral infection may be a major cause of febrile episodes in infants younger than three months. If UTI could be excluded, the presence of CRP levels ≥1.87 mg/dL and fevers of ≥38.9℃ can be used as criteria to rule out SBI in these infants