Bell inequalities as constraints on unmeasurable correlations

The interpretation of the violation of Bell-Clauser-Horne inequalities is revisited, in relation with the notion of extension of QM predictions to unmeasurable correlations. Such extensions are compatible with QM predictions in many cases, in particular for observables with compatibility relations described by tree graphs. This implies classical representability of any set of correlations , , , and the equivalence of the Bell-Clauser-Horne inequalities to a non void intersection between the ranges of values for the unmeasurable correlation associated to different choices for B. The same analysis applies to the Hardy model and to the "perfect correlations" discussed by Greenberger, Horne, Shimony and Zeilinger. In all the cases, the dependence of an unmeasurable correlation on a set of variables allowing for a classical representation is the only basis for arguments about violations of locality and causality.Comment: Some modifications have been done in order to improve clarity of presentation and comparison with other approache

The MicroBioDiverSar Project: Exploring the Microbial Biodiversity in Ex Situ Collections of Sardinia

In the last decades, biodiversity preservation has gained growing attention and many strategies, laws and regulations have been enacted by governments with this purpose. The Micro-BioDiverSar (MBDS) project, the first one regarding microbiological resources, funded by the Italian Minister of Agricultural, Food and Forestry Policies (Mipaaf) through the Law 194/2015, was aimed at surveying, cataloguing, and managing the microbial resources and the related information of three Sardinian collections (Agris BNSS, Uniss, and Unica). While microorganisms were reordered and inventoried, a federated database, accessible via the web, was designed by the bioinformatician of Ospedale Policlinico San Martino of Genova, according to both international standards and laboratory needs. The resulting MBDS collection boasts a great richness of microbial resources. Indeed, over 21,000 isolates, belonging to over 200 species of bacteria, yeasts, and filamentous fungi isolated from different matrices, mainly food, of animal and vegetable origin, collected in over 50 years, were included in the database. Currently, about 2000 isolates, belonging to 150 species, are available online for both the scientific community and agri-food producers. The huge work done allowed one to know the consistency and the composition of most of the patrimony of the Sardinian microbial collections. Furthermore, the MBDS database has been proposed as a model for other Italian collections that, as the MBDS partners, are part of the Joint Research UnitMIRRI-IT Italian collections network, with the aim of overcoming fragmentation, facing sustainability challenges, and improving the quality of the management of the collections

Role of key-regulator genes in melanoma susceptibility and pathogenesis among patients from South Italy

Background. Several genetic alterations have been demonstrated to contribute to the development and progression of melanoma. In this study, we further investigated the impact of key-regulator genes in susceptibility and pathogenesis of such a disease. Methods. A large series (N = 846) of sporadic and familial cases originating from South Italy was screened for germline mutations in p16CDKN2A, BRCA2, and MC1R genes by DHPLC analysis and automated DNA sequencing. Paired primary melanomas and lymph node metastases from same patients (N = 35) as well as melanoma cell lines (N = 18) were analyzed for somatic mutations in NRAS, BRAF, and p16CDKN2A genes. Results. For melanoma susceptibility, investigations at germline level indicated that p16CDKN2A was exclusively mutated in 16/545 (2.9%) non-Sardinian patients, whereas BRCA2 germline mutations were observed in 4/91 (4.4%) patients from North Sardinia only. Two MC1R germline variants, Arg151Cys and Asp294His, were significantly associated with melanoma in Sardinia. Regarding genetic events involved in melanoma pathogenesis at somatic level, mutually-exclusive mutations of NRAS and BRAF genes were observed at quite same rate (about two thirds) in cultured and in vivo melanomas (either primary or metastatic lesions). Conversely, p16CDKN2A gene alterations were observed at increased rates moving from primary to metastatic melanomas and melanoma cell lines. Activation of the ERK gene product was demonstrated to be consistently induced by a combination of molecular alterations (NRAS/BRAF mutations and p16CDKN2A silencing). Conclusion. Our findings further clarified that: a) mutation prevalence in melanoma susceptibility genes may vary within each specific geographical area; b) multiple molecular events are accumulating during melanomagenesis

Identification of a founder BRCA2 mutation in Sardinia

Sardinian population can be instrumental in defining the molecular basis of cancer, using the identity-by-descent method. We selected seven Sardinian breast cancer families originating from the northern-central part of the island with multiple affected members in different generations. We genotyped 106 members of the seven families and 20 control nuclear families with markers flanking BRCA2 locus at 13q12–q13. The detection of a common haplotype shared by four out of seven families (60%) suggests the presence of a founder BRCA2 mutation. Direct sequencing of BRCA2 coding exons of patients carrying the shared haplotype, allowed the identification of a ‘frame-shift’ mutation at codon 2867 (8765delAG), causing a premature termination-codon. This mutation was found in breast cancer patients as well as one prostate and one bladder cancer patient with shared haplotype. We then investigated the frequency of 8765delAG in the Sardinian breast cancer population by analysing 270 paraffin-embedded normal tissue samples from breast cancer patients. Five patients (1.7%) were found to be positive for the 8765delAG mutation. Discovery of a founder mutation in Sardinia through the identity-by-descent method demonstrates that this approach can be applied successfully to find mutations either for breast cancer or for other types of tumours. © 2000 Cancer Research Campaig

Measurement of the Helicity Fractions of W Bosons from Top Quark Decays Using Fully Reconstructed top-antitop Events with CDF II

We present a measurement of the fractions F_0 and F_+ of longitudinally polarized and right-handed W bosons in top quark decays using data collected with the CDF II detector. The data set used in the analysis corresponds to an integrated luminosity of approximately 318 pb -1. We select ttbar candidate events with one lepton, at least four jets, and missing transverse energy. Our helicity measurement uses the decay angle theta*, which is defined as the angle between the momentum of the charged lepton in the W boson rest frame and the W momentum in the top quark rest frame. The cos(theta*) distribution in the data is determined by full kinematic reconstruction of the ttbar candidates. We find F_0 = 0.85 +0.15 -0.22 (stat) +- 0.06 (syst) and F_+ = 0.05 +0.11 -0.05 (stat) +- 0.03 (syst), which is consistent with the standard model prediction. We set an upper limit on the fraction of right-handed W bosons of F_+ < 0.26 at the 95% confidence level.Comment: 11 pages, 2 figures, submitted to Phys. Rev.

Cytological and histological diagnosis of lung cancer in Sardinia and Italy in the 1990s

Background. Up to 30-50% of all lung cancer cases remain without cyto-histological characterisation. The aim of our study was to evaluate retrospectively the proportion of histological and/or cytological diagnosis in patients with lung cancer in Sardinia. Methods. Data was gathered by consulting the hospital registers and case notes of individual patients released from hospital with a diagnosis of Lung Cancer at all medical centres throughout Sardinia. In gathering patients' data, we focused our attention on cytological and histological procedures through which allowed the lung cancer was diagnosed. Cancer Registries data was utilised to compare our data with national and Sassari province data. Results. From 1991 to 1996 there was a total of 3146 lung cancer patients registered in Sardinia. 1902 patients (60.5%) had a histological diagnosis, 142 patients (4.5%) a cytological diagnosis while in 1102 patients (35%) the diagnosis was performed without any pathological validation. Conclusions. Our study has shown that lung cancer diagnosis is supported by pathological verification in 65% of cases while in remaining 35% of patients the diagnosis is based only on clinical and radiological reports. In Italy data from Cancer Registries report the percentage of cyto- histological diagnosis to be 70% with the percentage of cytological diagnosis being higher than in Sardinia

Measurement of σ(Λb)/σ(B0)×BR(Λb→Λcπ−)/BR(B0→D+π−)\sigma(\Lambda_b)/\sigma(B^0) \times BR(\Lambda_b\to\Lambda_c\pi^-) / BR(B^0\to D^+\pi^-) in ppˉp\bar{p} Collisions at s=1.96\sqrt{s}=1.96 TeV

We present the first observation of the baryon decay $\Lambda_b\to\Lambda_c\pi^-$ followed by $\Lambda_c\to p K^-\pi^+$ in 106 pb-1 of $p\bar{p}$ collisions at $\sqrt{s} = 1.96$ TeV in the CDF experiment. In order to reduce systematic error, the measured rate for $\Lambda_b$ decay is normalized to the kinematically similar meson decay $B^0\to D^+\pi^-$ followed by $D^+\to\pi^+K^-\pi^+$. We report the ratio of production cross sections ($\sigma$) times the ratio of branching fractions (BR) for the momentum region integrated above $p_T > 6$ GeV/c and pseudorapidity range $|\eta| < 1.3$: $\sigma(p\bar{p}\to \Lambda_b X) / \sigma (p\bar{p}\to B^0 X) \times BR(\Lambda_b\to\Lambda_c\pi^-) / BR(B^0\to D^+\pi^-) = 0.82 \pm 0.08(stat) \pm 0.11(syst) \pm 0.22 (BR(\Lambda_c\to p K^-\pi^+))$.Comment: Submitted to Phys.Rev.Let

Measurement of the Lambda_b Lifetime in Lambda_b --> J/psi Lambda0 in p-pbar Collisions at sqrt(s)=1.96 TeV

We report a measurement of the Lambda_b lifetime in the exclusive decay Lambda_b --> J/psi Lambda0 in p-pbar collisions at sqrt(s) = 1.96 TeV using an integrated luminosity of 1.0 fb^{-1} of data collected by the CDF II detector at the Fermilab Tevatron. Using fully reconstructed decays, we measure tau(Lambda_b) = 1.593 ^{+0.083}_{-0.078} (stat.) +- 0.033 (syst.) ps. This is the single most precise measurement of tau(Lambda_b) and is 3.2 sigma higher than the current world average.Comment: 7 Pages, 2 Figures, 1 Table. Submitted to Phys. Rev. Let

Precision measurement of the top quark mass from dilepton events at CDF II

We report a measurement of the top quark mass, M_t, in the dilepton decay channel of $t\bar{t}\to b\ell'^{+}\nu_{\ell'}\bar{b}\ell^{-}\bar{\nu}_{\ell}$ using an integrated luminosity of 1.0 fb^{-1} of p\bar{p} collisions collected with the CDF II detector. We apply a method that convolutes a leading-order matrix element with detector resolution functions to form event-by-event likelihoods; we have enhanced the leading-order description to describe the effects of initial-state radiation. The joint likelihood is the product of the likelihoods from 78 candidate events in this sample, which yields a measurement of M_{t} = 164.5 \pm 3.9(\textrm{stat.}) \pm 3.9(\textrm{syst.}) \mathrm{GeV}/c^2, the most precise measurement of M_t in the dilepton channel.Comment: 7 pages, 2 figures, version includes changes made prior to publication by journa

Measurement of the Ratios of Branching Fractions B(Bs -> Ds pi pi pi) / B(Bd -> Dd pi pi pi) and B(Bs -> Ds pi) / B(Bd -> Dd pi)

Using 355 pb^-1 of data collected by the CDF II detector in \ppbar collisions at sqrt{s} = 1.96 TeV at the Fermilab Tevatron, we study the fully reconstructed hadronic decays B -> D pi and B -> D pi pi pi. We present the first measurement of the ratio of branching fractions B(Bs -> Ds pi pi pi) / B(Bd -> Dd pi pi pi) = 1.05 pm 0.10 (stat) pm 0.22 (syst). We also update our measurement of B(Bs -> Ds pi) / B(Bd -> Dd pi) to 1.13 pm 0.08 (stat) pm 0.23 (syst) improving the statistical uncertainty by more than a factor of two. We find B(Bs -> Ds pi) = [3.8 pm 0.3 (stat) pm 1.3 (syst)] \times 10^{-3} and B(Bs -> Ds pi pi pi) = [8.4 pm 0.8 (stat) pm 3.2 (syst)] \times 10^{-3}.Comment: 7 pages, 2 figure