Observation of the B(s)(0)→η'η' Decay

The first observation of the B(s)(0)→η'η' decay is reported. The study is based on a sample of proton-proton collisions corresponding to 3.0  fb(-1) of integrated luminosity collected with the LHCb detector. The significance of the signal is 6.4 standard deviations. The branching fraction is measured to be [3.31±0.64(stat)±0.28(syst)±0.12(norm)]×10(-5), where the third uncertainty comes from the B(±)→η'K(±) branching fraction that is used as a normalization. In addition, the charge asymmetries of B(±)→η'K(±) and B(±)→ϕK(±), which are control channels, are measured to be (-0.2±1.3)% and (+1.7±1.3)%, respectively. All results are consistent with theoretical expectations.

Measurement of CP Violation in B0→J/ψK{S}^{0} Decays

Measurements are presented of the CP violation observables S and C in the decays of B(0) and Bover ¯]0 mesons to the J/ψK(S)(0) final state. The data sample corresponds to an integrated luminosity of 3.0  fb(-1) collected with the LHCb experiment in proton-proton collisions at center-of-mass energies of 7 and 8 TeV, and contains a total of 41 560 selected B^{0} and B[over ¯]^{0} decays. The analysis of the time evolution of these decays yields S=0.731±0.035(stat)±0.020(syst) and C=-0.038±0.032(stat)±0.005(syst). In the standard model, S equals sin(2β) to a good level of precision. The values are consistent with the current world averages and with the standard model expectations.

Measurement of the [Formula: see text] production cross-section in proton-proton collisions via the decay [Formula: see text]

The production of the [Formula: see text] state in proton-proton collisions is probed via its decay to the [Formula: see text] final state with the LHCb detector, in the rapidity range [Formula: see text] and in the meson transverse-momentum range [Formula: see text]. The cross-section for prompt production of [Formula: see text] mesons relative to the prompt [Formula: see text] cross-section is measured, for the first time, to be [Formula: see text] at a centre-of-mass energy [Formula: see text] using data corresponding to an integrated luminosity of 0.7 fb[Formula: see text], and [Formula: see text] at [Formula: see text] using 2.0 fb[Formula: see text]. The uncertainties quoted are, in order, statistical, systematic, and that on the ratio of branching fractions of the [Formula: see text] and [Formula: see text] decays to the [Formula: see text] final state. In addition, the inclusive branching fraction of [Formula: see text]-hadron decays into [Formula: see text] mesons is measured, for the first time, to be [Formula: see text], where the third uncertainty includes also the uncertainty on the [Formula: see text] inclusive branching fraction from [Formula: see text]-hadron decays. The difference between the [Formula: see text] and [Formula: see text] meson masses is determined to be [Formula: see text].

Search for long-lived particles decaying to jet pairs

A search is presented for long-lived particles with a mass between 25 and 50 [Formula: see text] and a lifetime between 1 and 200[Formula: see text] in a sample of proton-proton collisions at a centre-of-mass energy of [Formula: see text] TeV, corresponding to an integrated luminosity of 0.62 [Formula: see text], collected by the LHCb detector. The particles are assumed to be pair-produced by the decay of a standard model-like Higgs boson. The experimental signature of the long-lived particle is a displaced vertex with two associated jets. No excess above the background is observed and limits are set on the production cross-section as a function of the long-lived particle mass and lifetime.

Measurement of Bc+ Production in Proton-Proton Collisions at √[s]=8 TeV

Production of Bc+ mesons in proton-proton collisions at a center-of-mass energy of 8 TeV is studied with data corresponding to an integrated luminosity of 2.0  fb-1 recorded by the LHCb experiment. The ratio of production cross sections times branching fractions between the Bc+→J/ψπ+ and B+→J/ψK+ decays is measured as a function of transverse momentum and rapidity in the regions 0<pT<20  GeV/c and 2.0<y<4.5. The ratio in this kinematic range is measured to be (0.683±0.018±0.009)%, where the first uncertainty is statistical and the second systematic.

Observation of two new Ξ(b)(-) baryon resonances

Two structures are observed close to the kinematic threshold in the Ξ(b)(0)π(-) mass spectrum in a sample of proton-proton collision data, corresponding to an integrated luminosity of 3.0  fb(-1), recorded by the LHCb experiment. In the quark model, two baryonic resonances with quark content bds are expected in this mass region: the spin-parity J(P)=(1/2)(+) and J(P)=(3/2)(+) states, denoted Ξ(b)('-) and Ξ(b)(*-). Interpreting the structures as these resonances, we measure the mass differences and the width of the heavier state to be m(Ξ(b)('-))-m(Ξ(b)(0))-m(π(-))=3.653±0.018±0.006  MeV/c(2), m(Ξ(b)(*-))-m(Ξ(b)(0))-m(π(-))=23.96±0.12±0.06  MeV/c(2), Γ(Ξ(b)(*-))=1.65±0.31±0.10  MeV, where the first and second uncertainties are statistical and systematic, respectively. The width of the lighter state is consistent with zero, and we place an upper limit of Γ(Ξ(b)('-))<0.08  MeV at 95% confidence level. Relative production rates of these states are also reported.

Precision measurement of CP violation in B(S)(0)→J/ΨK+K- decays

The time-dependent CP asymmetry in B(s)(0)→J/ψK+K- decays is measured using pp collision data, corresponding to an integrated luminosity of 3.0  fb-1, collected with the LHCb detector at center-of-mass energies of 7 and 8 TeV. In a sample of 96,000 B(s)(0)→J/ψK+K- decays, the CP-violating phase ϕs is measured, as well as the decay widths ΓL and ΓH of the light and heavy mass eigenstates of the B(s)(0)-B[over ¯]s0 system. The values obtained are ϕs=-0.058±0.049±0.006  rad, Γs≡(ΓL+ΓH)/2=0.6603±0.0027±0.0015  ps-1, and ΔΓs≡ΓL-ΓH=0.0805±0.0091±0.0032  ps-1, where the first uncertainty is statistical and the second, systematic. These are the most precise single measurements of those quantities to date. A combined analysis with Bs0→J/ψπ+π- decays gives ϕs=-0.010±0.039  rad. All measurements are in agreement with the standard model predictions. For the first time, the phase ϕs is measured independently for each polarization state of the K+K- system and shows no evidence for polarization dependence.

Measurement of the semileptonic CP asymmetry in B0-B[over ¯]0 mixing

The semileptonic CP asymmetry in B0-B[over ¯]0 mixing, a(sl)(d), is measured in proton-proton collision data, corresponding to an integrated luminosity of 3.0  fb-1, recorded by the LHCb experiment. Semileptonic B0 decays are reconstructed in the inclusive final states D-μ+ and D*-μ+, where the D- meson decays into the K+π-π- final state and the D*- meson into the D[over ¯]0(→K+π-)π- final state. The asymmetry between the numbers of D(*)-μ+ and D(*)+μ- decays is measured as a function of the decay time of the B0 mesons. The CP asymmetry is measured to be a(sl)(d)=(-0.02±0.19±0.30)%, where the first uncertainty is statistical and the second systematic. This is the most precise measurement of a(sl)(d) to date and is consistent with the prediction from the standard model.

Precision measurement of the mass and lifetime of the Ξb⁻ baryon

We report on measurements of the mass and lifetime of the Ξ(b)⁻ baryon using about 1800 Ξ(b)⁻ decays reconstructed in a proton-proton collision data set corresponding to an integrated luminosity of 3.0  fb⁻¹ collected by the LHCb experiment. The decays are reconstructed in the Ξ(b)⁻→Ξ(c)⁰π⁻, Ξ(c)⁰→pK⁻K⁻π⁺ channel and the mass and lifetime are measured using the Λ(b)⁰→Λ(c)⁺π⁻ mode as a reference. We measure M(Ξ(b)⁻)-M(Λ(b)⁰)=178.36±0.46±0.16  MeV/c², (τ(Ξ(b)⁻)/τ(Λ(b)⁰)=1.089±0.026±0.011, where the uncertainties are statistical and systematic, respectively. These results lead to a factor of 2 better precision on the Ξ(b)⁻ mass and lifetime compared to previous best measurements, and are consistent with theoretical expectations.

Measurement of the CP-violating phase ϕs in Bs(0)→Ds(+)Ds(-) decays

We present a measurement of the CP-violating weak mixing phase ϕs using the decay Bs(0)→Ds(+)Ds(-) in a data sample corresponding to 3.0 fb(-1) of integrated luminosity collected with the LHCb detector in pp collisions at center-of-mass energies of 7 and 8 TeV. An analysis of the time evolution of the system, which does not use the constraint |λ|=1 to allow for the presence of CP violation in decay, yields ϕs=0.02±0.17(stat)±0.02(syst)  rad, |λ|=0.91(-0.15)(+0.18)(stat)±0.02(syst). This result is consistent with the standard model expectation.

Observation of overlapping spin-1 and spin-3 D0K- resonances at mass 2.86 GeV/c2

The resonant substructure of B(s)(0) → D(0)K(-)π(+) decays is studied using a data sample corresponding to an integrated luminosity of 3.0 fb(-1) of pp collision data recorded by the LHCb detector. An excess at m(D(0)K(-))≈ 2.86 GeV/c(2) is found to be an admixture of spin-1 and spin-3 resonances. Therefore, the D(sJ)*(2860)(-) state previously observed in inclusive e(+)e(-) → D(0)K(-)X and pp → D(0)K(-)X processes consists of at least two particles. This is the first observation of a heavy flavored spin-3 resonance, and the first time that any spin-3 particle has been seen to be produced in B decays. The masses and widths of the new states and of the D(s2)*(2573)(-) meson are measured, giving the most precise determinations to date.

First observation of a baryonic Bc+ decay

A baryonic decay of the B(c)(+) meson, B(c)(+) → J/ψppπ(+), is observed for the first time, with a significance of 7.3 standard deviations, in pp collision data collected with the LHCb detector and corresponding to an integrated luminosity of 3.0 fb(-1) taken at center-of-mass energies of 7 and 8 TeV. With the B(c)(+) → J/ψπ(+) decay as the normalization channel, the ratio of branching fractions is measured to be B(B(c)(+) → J/ψppπ(+))/B(B(c)(+) → J/ψπ(+)) = 0.143(-0.034)(+0.039)(stat) ± 0.013(syst). The mass of the B(c)(+) meson is determined as M(B(c)(+) = 6274.0 ± 1.8(stat) ± 0.4(syst) MeV/c(2), using the B(c)(+) → J/ψppπ(+) channel.

Digital configurable instrument for emulation of signals from radiation detectors

The paper presents a digital instrument characterized by a specially designed architecture that is able to emulate in real time signals from a generic radiation detection system. The instrument is not a pulse generator of recorded shapes but a synthesizer of random pulses compliant to programmable statistics for height and starting time of events. Completely programmable procedures for emulation of noise, disturbances, and reference level variation are implemented.

Towards An Improvement of Hospital Services and Streamlining of Health Care Costs: The DRG Analysis in Italy

The term Diagnosis-related Group (DRG) refers to a classification system used to assess hospital services with the aim of a better management of health care costs and improving performance. The DRG system focuses on the utilization of resources, and is not concerned with the specific type of care provided to the patient. This system highlights any diseconomies and eventual critical aspects of the hospital system. This article, starting from the history of heath care financing in Italy and pointing out the difficulty to define the "quality" of health care services, describes the variables used to evaluate correctly hospital performance based on the DRG system. These include Average Length of Stay, Average Daily Patient Load, Comparative Performance Index, and Case Mix Index.

P01-248-Theory of mind, moral judgments and neuropsychological functioning in patients with bipolar disorders

Introduction

Several studies revealed that cognitive functioning in BPD are impaired not only in the acute phase but over time (Mur et al., 2008). On Theory of Mind (ToM) recent studies found a impairment of this ability in remitted patients, supporting the theory that ToM deficits are trait-dependent (Bora et al., 2009) in contrast with another study that suggest a partially dependence(Wolf et al. 2010).

Objectives

We explored: a) ToM in BPD investigating two cognitive processes: emotional recognition, second order beliefs attribution; b) Moral judgments in BPD; c) possible effects of neuropsychological functioning on ToM task and moral dilemmas.

Aims

The principal aim is to investigate the domain specificity of ToM and Moral sense, studying selective impairments.

Method

A total of 20 patients with bipolar I disorder were tested and 20 healthy controls. We use a complete neuropsychological assessment, two ToM tasks (Eyes test, Sullivan's stories) and we added two moral dilemmas to asses moral judgment Results: We found ToM deficits in BDP, with a multiple correlation between ToM and neuropsychological functioning. Also we found for the first time a impairment on personal moral dilemma, with a correlation between emotional recognition and moral judgments.

Conclusion

Patients with BPD are impaired in ToM partially independent of other cognitive dysfunctions and in moral reasoning.

High-linearity analog-to-digital acquisition board for photon-timing applications

Nowadays a wide range of scientific applications require the detection of very weak and fast luminescence signals in the time domain. Single molecule spectroscopy, diffuse optical tomography, time-resolved emission spectra are only a few examples among them. Advanced time-correlated single photon counting, that relies on multidetector and multidimensional acquisition, reveals itself as a powerful technique to gather deeper insight into various photochemical and biological processes. In this paper we present a high-speed, high-linearity A/D acquisition board that is designed as a building block for a compact, low-cost, multidetector acquisition system for photon-timing experiments. The prototype has been experimentally tested and the results fully comply the goal design specifications.

Antibiotic effects on SO4(2-) uptake in human erythrocytes

The erythrocyte is a cell highly exposed to oxygen pressure that, in turn, provokes oxidative stress involving loss of SH-groups, cell shrinkage by activation of K(+)-Cl(-) cotransport (KCC) and membrane destabilization which plays an important role in the premature haemolysis of red blood cells (RBCs). Oxidative stress provoked by chemicals frequently occurs in human erythrocytes. The aim of this study was to test whether the antibiotics alter the redox state and investigate their influences on band 3 protein that is involved in the facilitated electro neutral exchange of Cl(-) for HCO(3)(-) across the membrane of mammalian erythrocytes. Normal erythrocytes were treated with some antibiotics and thiol oxidizing agent N-ethylmaleimide (NEM) and tested for sulphate uptake, K(+) efflux and for glutathione (GSH) concentration as an index of oxidative stress. The rate constant of SO(4)(=) uptake measured in erythrocytes treated with antibiotics as well as NEM was decreased with respect to control cells as a result of band 3 SH-groups oxidation or the stress-induced K(+)-Cl(-) symport-mediated cell shrinkage. In fact, this hypothesis was verified by increased K(+) efflux and decreased GSH values measured in treated erythrocytes compared to controls.

Activation of the ER stress gene gadd153 by hepatitis C virus sensitizes cells to oxidant injury

HCV induces endoplasmic reticulum (ER) stress which correlates with transcriptional induction of ER stress genes. Previously, we reported that expression of HCV structural proteins activates the ER stress and pro-apoptotic gene gadd153 which plays a relevant role in cell death induced by oxidative stress. In the present study, using human hepatic cell lines Huh7 carrying a full-length HCV replicon, we demonstrated that replication and expression of the complete set of HCV proteins were associated with elevated expression of gadd153. Analysis of gadd153 promoter activity revealed that both the ATF4 and the ATF6 pathways, which are typically induced during ER stress response, contribute to the induction of gadd153 in HCV replicon cells. Activation of the ATF4 pathway was confirmed by identification of increased levels of ATF4 protein in replicon cells. Importantly, we showed that, following H2O2 treatment, gadd153 gene reached higher levels of expression in replicon cells. Consistent with the marked induction of the pro-apoptotic gene gadd153, HCV replicon cells showed an increased vulnerability to oxidant injury. Treatment of replicon cells with a specific small interfering RNA, targeted to gadd153 gene, reduced basal expression of gadd153 and decreased cell death following H2O2. These findings suggest that gadd153 may play a major role in sensitivity of HCV replicon cell to oxidative stress.

Abnormal cobalamin-dependent transmethylation in AIDS-associated myelopathy

BACKGROUND

White matter vacuolization of the spinal cord is common in patients with AIDS and may lead to clinical manifestations of myelopathy. The pathogenesis of AIDS-associated myelopathy (AM) is unknown and may be related to metabolic abnormalities rather than to direct HIV infection. The striking pathologic similarity between AM and the vacuolar myelopathy associated with vitamin B(12) deficiency suggests that abnormal metabolism of the B(12)-dependent transmethylation pathway may be important in the pathogenesis of AM.

METHODS

The authors compared S-adenosyl-methionine (SAM), methionine, homocysteine, and glutathione in serum and CSF of 15 patients with AM vs. 13 HIV-infected controls without myelopathy (HWM). They also compared the results with a non-HIV--infected reference population (NC). All patients had normal B(12), folate, and methylmalonic acid levels.

RESULTS

There was a decrease in CSF SAM in the AM group compared with the HWM group (p < 0.0001) and the NC group (p < 0.0001). CSF SAM in the HWM group was also lower than that in the NC group (p = 0.015). Serum methionine was also reduced in serum of the myelopathic group compared with the NC group (p = 0.006).

CONCLUSIONS

AM is associated with an abnormality of the vitamin B(12)-dependent transmethylation pathway.

AIDS and AIDS-treatment neuropathies

AIDS and AIDS-treatment neuropathies are common in individuals infected with HIV. As patients live longer due to improved antiretroviral therapies, the impact of painful neuropathy on patients' lives may increase. Several antiretroviral medications are known to cause toxic neuropathy in AIDS patients; but this may be outweighed by the beneficial effects of viral suppression. Current theories on the pathogenesis of AIDS neuropathies include mitochondrial toxicity secondary to gamma-DNA polymerase inhibition and subsequent abnormal mitochondrial DNA synthesis. Treatment of AIDS neuropathies is directed toward relief of symptoms, however, new evidence suggests that aggressive antiretroviral therapy may also be effective.

Mutagenesis of hepatitis C virus E1 protein affects its membrane-permeabilizing activity

The E1 glycoprotein of hepatitis C virus is a transmembrane glycoprotein with a C-terminal anchor domain. When expressed in Escherichia coli, E1 induces a change in membrane permeability that is toxic to the bacterial cell. The C-terminal hydrophobic region (aa 331-383) of E1 is mainly responsible for membrane association and for inducing changes in membrane permeability. These observed changes are similar to those produced in E. coli by influenza virus M2, human immunodeficiency virus gp41 and poliovirus 3AB proteins, whose hydrophobic domains are thought to cause pore formation in biological membranes. To further characterize the activity of E1 at a molecular level, the membrane-permeabilizing ability of a second internal hydrophobic region (aa 262-291) was examined by expressing different deletion mutants of E1 in an E. coli system that is widely used for analysing membrane-active proteins from other animal viruses. Moreover, highly conserved amino acids in the C-terminal hydrophobic region were mutated to identify residues that are critical for inducing changes in membrane permeability. Analysis of cell growth curves of recombinant cultures and membrane-permeability assays revealed that synthesis of this fragment increased the flux of small compounds through the membrane and caused progressive cell lysis, suggesting that this domain has membrane-active properties. Furthermore, analysis of C-terminal mutants indicated that the conserved amino acids Arg(339), Trp(368) and Lys(370) play a critical role in protein function, as both cell lysis and changes in membrane permeability induced by the wild-type clone could be blocked by substitutions in these positions.

[Experience at a branch center of the National HIV Protease Inhibitor Registry]

In the present study we show our experience as one of the Centers (center 006) of the Italian Index of Protease Inhibitors (PI). In this multicentric, observational study we studied HIV-positive naive patients for antiretroviral therapy with protease inhibitors. From 8/1/97 to 31/1/98 in our department 64 patients were enrolled and followed up through an electronic medical sheet in order to evaluate efficacy, tolerability, toxicity and compliance of treatment with PI. Our results show a reduction in AIDS-related mortality and a decrease in AIDS defining diseases: in particular data show an increase in CNS pathologies in comparison with other opportunistic events. Moreover, in patients non complaints to therapy, the progression of the disease was more frequent. The side effects more frequently observed during PI treatment were hypertrigliceridaemia and lipodystrophy; gynaecomastia and hyperprolactinaemia were even present, perhaps as expression of direct metabolic action of HAART therapy.