A Headspace Solid Phase Microextraction (HS-SPME) method for the chromatographic determination of alkylpyrazines in cocoa samples

A Headspace Solid Phase Microextraction (HS-SPME) procedure for isolation and determination of alkylpyrazines in cocoa liquor, using Gas Chromatography with Flame Ionization Detection (GC-FID) for the separation and detection of the analytes, is presented here. The HS-SPME operational conditions were optimized using extractions of samples spiked with known amounts of alkylpyrazines typically found on cocoa products. The maximum extraction efficiency was obtained using SPME fibers coated with 65 µm Carbowax/divinylbenzene. Additionally, the best results were achieved with extraction temperature of 60 ºC, 15 min of sample/headspace equilibration time and 45 min extraction time. It was also observed that suspending the samples in saturated aqueous NaCl solution during extractions resulted in a significant increment on the peak areas. This procedure was found to be effective to determine the so-called pyrazinic ratios (quotient between peak areas of alkylpyrazines), which are useful as quality parameters for cocoa liquor.Um procedimento de Microextração em Fase Sólida em Headspace (HS-SPME) para isolamento e determinação de alquilpirazinas em liquor de cacau, usando Cromatografia Gasosa com Detecção por Ionização em Chama (GC-FID) é apresentado aqui. As condições operacionais de HS-SPME foram otimizadas usando extrações de amostras fortificadas com quantidades conhecidas de alquilpirazinas tipicamente encontradas em derivados de cacau. A eficiência máxima de extração foi obtida com fibras de SPME recobertas com 65 µm de Carbowax/divinilbenzeno. Em adição, os melhores resultados foram obtidos usando 60 ºC como temperatura de extração, 15 min como tempo de equilíbrio amostra/headspace e 45 min como tempo de extração. Observou-se também que o uso de solução aquosa saturada de NaCl para suspender as amostras durante as extrações resultou em um incremento significativo nas áreas dos picos. Este procedimento se mostrou efetivo para a determinação das razões pirazínicas (quocientes entre as áreas dos picos de alquilpirazinas), que são úteis como parâmetros de qualidade para liquor de cacau.267271Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Measurement of the K_L \to \pi\mu\nu form factor parameters with the KLOE detector

Using 328 pb^{-1}of data collected at DAFNE corresponding to $\sim$ 1.8 million $K_L\to \pi\mu\nu$ decays, we have measured the $K_{\mu 3}$ form factor parameters. The structure of the $K-\pi$ vector-current provides information about the dynamics of the strong interaction; its knowledge is necessary for evaluation of the phase-space integral required for measuring the CKM matrix element $V_{us}$ and for testing lepton universality in kaon decays. Using a new parametrization for the vector and scalar form factors, we find $\lambda_+$=\pt(25.7\pm 0.6),-3, and $\lambda_0$=\pt(14.0\pm 2.1),-3,. Our result for $\lambda_0$, together with recent lattice calculations of $f_\pi$, $f_K$ and $f(0)$, satisfies the Callan-Trieman relatio

Data acquisition and monitoring for the KLOE detector

none77siThe Data Acquisition system for the KLOE experiment, presently running at the Laboratori Nazionali di Frascati DAPhiNE collider, has been designed to sustain an acquisition throughput of 50 Mbyte/s for an event rate of 10 kHz. its two major components are the front end data readout, based on custom buses, and a complex network of computers and storage devices hosting a set of distributed processes. The end result is a seamless data transport from the readout system to the storage library, accompanied by concurrent on line calibrations and data quality control.openA. ALOISIO; F. AMBROSINO; S. CAVALIERE; F. CEVENINI; C. DI DONATO; A. DORIA; D. FIORE; L. MEROLA; G. PIROZZI; G. SARACINO; M. ANTONELLI; F. BOSSI; P. CIAMBRONE; P. DE SIMONE; S. DELL'AGNELLO; M.L. FERRER; G. FINOCCHIARO; C. FORTI; C. GATTI; S. GIOVANNELLA; W. GRANDEGGER; G. LANFRANCHI; B. MARTINI; W. MEI; S. MISCETTI; M. MOULSON; F. MURTAS; M. PALUTAN; L. PASSALACQUA; F. PELUCCHI; P. SANTANGELO; B. SCIASCIA; I. SFILIGOI; J. SHAN; T. SPADARO; P. VALENTE; Y ZHOU; C. BINI; V. BOCCI; G. CABIBBO; R. CALOI; A. CARDINI; E. DE LUCIA; A. DI DOMENICO; P. GAUZZI; E. PASQUALUCCI; M. PASSASEO; D. PICCA; L. PONTECORVO; E. VALENTE; S. VENEZIANO; P. BRANCHINI; E. GRAZIANI; A. PASSERI; A. FERRARI; E. SPIRITI; C. STANESCU; L. TORTORA; M. CASARSA; G. CATALDI; E. GORINI; M. PRIMAVERA; A. VENTURA; G. DE ROBERTIS; P. GUARNACCIA; A. DENIG; CHEN-CHENG KUO; S. MULLER; B. VALERIANI; S. DI FALCO; M. INCAGLI; G. VENANZONI; R. MESSI; L. PACCIANI; E. SANTOVETTI; J. LEE-FRANZINI; M. MARTEMIANOVA., Aloisio; F., Ambrosino; S., Cavaliere; F., Cevenini; C., DI DONATO; A., Doria; D., Fiore; L., Merola; G., Pirozzi; G., Saracino; M., Antonelli; F., Bossi; P., Ciambrone; P., DE SIMONE; S., Dell'Agnello; M. L., Ferrer; G., Finocchiaro; C., Forti; C., Gatti; S., Giovannella; W., Grandegger; G., Lanfranchi; B., Martini; W., Mei; S., Miscetti; M., Moulson; F., Murtas; M., Palutan; L., Passalacqua; F., Pelucchi; P., Santangelo; B., Sciascia; I., Sfiligoi; J., Shan; T., Spadaro; P., Valente; Y., Zhou; C., Bini; V., Bocci; G., Cabibbo; R., Caloi; A., Cardini; E., DE LUCIA; A., DI DOMENICO; P., Gauzzi; E., Pasqualucci; M., Passaseo; D., Picca; L., Pontecorvo; E., Valente; S., Veneziano; P., Branchini; E., Graziani; A., Passeri; A., Ferrari; E., Spiriti; C., Stanescu; L., Tortora; M., Casarsa; G., Cataldi; Gorini, Edoardo; Primavera, Margherita; Ventura, Andrea; G., DE ROBERTIS; P., Guarnaccia; A., Denig; CHEN CHENG, Kuo; S., Muller; B., Valeriani; S., DI FALCO; M., Incagli; G., Venanzoni; R., Messi; L., Pacciani; E., Santovetti; J., LEE FRANZINI; M., Martemiano

Measurements of Higgs boson production and couplings in diboson final states with the ATLAS detector at the LHC

Measurements are presented of production properties and couplings of the recently discovered Higgs boson using the decays into boson pairs, H →γ γ, H → Z Z∗ →4l and H →W W∗ →lνlν. The results are based on the complete pp collision data sample recorded by the ATLAS experiment at the CERN Large Hadron Collider at centre-of-mass energies of √s = 7 TeV and √s = 8 TeV, corresponding to an integrated luminosity of about 25 fb−1. Evidence for Higgs boson production through vector-boson fusion is reported. Results of combined fits probing Higgs boson couplings to fermions and bosons, as well as anomalous contributions to loop-induced production and decay modes, are presented. All measurements are consistent with expectations for the Standard Model Higgs boson

Standalone vertex finding in the ATLAS muon spectrometer

A dedicated reconstruction algorithm to find decay vertices in the ATLAS muon spectrometer is presented. The algorithm searches the region just upstream of or inside the muon spectrometer volume for multi-particle vertices that originate from the decay of particles with long decay paths. The performance of the algorithm is evaluated using both a sample of simulated Higgs boson events, in which the Higgs boson decays to long-lived neutral particles that in turn decay to bbar b final states, and pp collision data at √s = 7 TeV collected with the ATLAS detector at the LHC during 2011

Measurement of the top quark-pair production cross section with ATLAS in pp collisions at \sqrt{s}=7\TeV

A measurement of the production cross-section for top quark pairs(\ttbar) in $pp$ collisions at \sqrt{s}=7 \TeV is presented using data recorded with the ATLAS detector at the Large Hadron Collider. Events are selected in two different topologies: single lepton (electron $e$ or muon $\mu$) with large missing transverse energy and at least four jets, and dilepton ($ee$, $\mu\mu$ or $e\mu$) with large missing transverse energy and at least two jets. In a data sample of 2.9 pb-1, 37 candidate events are observed in the single-lepton topology and 9 events in the dilepton topology. The corresponding expected backgrounds from non-\ttbar Standard Model processes are estimated using data-driven methods and determined to be $12.2 \pm 3.9$ events and $2.5 \pm 0.6$ events, respectively. The kinematic properties of the selected events are consistent with SM \ttbar production. The inclusive top quark pair production cross-section is measured to be \sigmattbar=145 \pm 31 ^{+42}_{-27} pb where the first uncertainty is statistical and the second systematic. The measurement agrees with perturbative QCD calculations.Comment: 30 pages plus author list (50 pages total), 9 figures, 11 tables, CERN-PH number and final journal adde

Measurement of the top quark pair cross section with ATLAS in pp collisions at √s=7 TeV using final states with an electron or a muon and a hadronically decaying τ lepton

A measurement of the cross section of top quark pair production in proton-proton collisions recorded with the ATLAS detector at the Large Hadron Collider at a centre-of-mass energy of 7 TeV is reported. The data sample used corresponds to an integrated luminosity of 2.05 fb -1. Events with an isolated electron or muon and a τ lepton decaying hadronically are used. In addition, a large missing transverse momentum and two or more energetic jets are required. At least one of the jets must be identified as originating from a b quark. The measured cross section, σtt-=186±13(stat.)±20(syst.)±7(lumi.) pb, is in good agreement with the Standard Model prediction

Hunt for new phenomena using large jet multiplicities and missing transverse momentum with ATLAS in 4.7 fb−1 of √s=7 TeV proton-proton collisions

Results are presented of a search for new particles decaying to large numbers of jets in association with missing transverse momentum, using 4.7 fb−1 of pp collision data at s√=7TeV collected by the ATLAS experiment at the Large Hadron Collider in 2011. The event selection requires missing transverse momentum, no isolated electrons or muons, and from ≥6 to ≥9 jets. No evidence is found for physics beyond the Standard Model. The results are interpreted in the context of a MSUGRA/CMSSM supersymmetric model, where, for large universal scalar mass m 0, gluino masses smaller than 840 GeV are excluded at the 95% confidence level, extending previously published limits. Within a simplified model containing only a gluino octet and a neutralino, gluino masses smaller than 870 GeV are similarly excluded for neutralino masses below 100 GeV

Biallelic loss-of-function mutation in NIK causes a primary immunodeficiency with multifaceted aberrant lymphoid immunity

Primary immunodeficiency disorders enable identification of genes with crucial roles in the human immune system. Here we study patients suffering from recurrent bacterial, viral and Cryptosporidium infections, and identify a biallelic mutation in the MAP3K14 gene encoding NIK (NF- B-inducing kinase). Loss of kinase activity of mutant NIK, predicted by in silico analysis and confirmed by functional assays, leads to defective activation of both canonical and non-canonical NF- B signalling. Patients with mutated NIK exhibit B-cell lymphopenia, decreased frequencies of class-switched memory B cells and hypogammaglobulinemia due to impaired B-cell survival, and impaired ICOSL expression. Although overall T-cell numbers are normal, both follicular helper and memory T cells are perturbed. Natural killer (NK) cells are decreased and exhibit defective activation, leading to impaired formation of NK-cell immunological synapses. Collectively, our data illustrate the non-redundant role for NIK in human immune responses, demonstrating that loss-of-function mutations in NIK can cause multiple aberrations of lymphoid immunity