161 research outputs found

    Integrated calcareous nannofossil biostratigraphy and magnetostratigraphy from the uppermost marine Eocene deposits of the southeastern Pyrenean foreland basin : evidences for marine Priabonian deposition

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    An integrated magneto-biostratigraphic study, based on calcareous nannofossils, was carried out on the Eocene uppermost marine deposits of the southeastern Pyrenean foreland basin. The study was performed along six sections of the upper portion of Igualada Formation, cropping out in the Vic area. Common late Middle/Upper Eocene nannofossil assemblages allow recognizing, within a normal magnetozone or immediately below, the FO of Istmolithus recurvus, which identifies the base of NP19 Zone, in the Priabonian. This event occurs within C16n.2n magnetozone in several oceanic and Mediterranean sections, which allows the correlation of the normal magnetozone in the Vic area to chron C16n.2n. This challenges previous magnetostratigraphic interpretations in the Vic area that correlated the uppermost marine sediments to chron C17n. The estimated age for the FO of I. recurvus is 36 Ma and collectively with the magnetostratigraphic data indicates that the uppermost marine sediments in the basin are of Priabonian age. The new results indicate that the entire chronology of the marine strata needs reassessment. The thickness of chron C16n.2n varies from 45 m in the Collsuspina area (southern sector) to about 270-290 m in the Sant Bartomeu del Grau area (northern sector), which is indicative of a marked asymmetry in the basin deposition

    Hybrid Particle-Field Molecular Dynamics Under Constant Pressure

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    Hybrid particle-field methods are computationally efficient approaches for modelling soft matter systems. So far applications of these methodologies have been limited to constant volume conditions. Here, we reformulate particle-field interactions to represent systems coupled to constant external pressure. First, we show that the commonly used particle-field energy functional can be modified to model and parameterize the isotropic contributions to the pressure tensor without interfering with the microscopic forces on the particles. Second, we employ a square gradient particle-field interaction term to model non-isotropic contributions to the pressure tensor, such as in surface tension phenomena. This formulation is implemented within the hybrid particle-field molecular dynamics approach and is tested on a series of model systems. Simulations of a homogeneous water box demonstrate that it is possible to parameterize the equation of state to reproduce any target density for a given external pressure. Moreover, the same parameterization is transferable to systems of similar coarse-grained mapping resolution. Finally, we evaluate the feasibility of the proposed approach on coarse-grained models of phospholipids, finding that the term between water and the lipid hydrocarbon tails is alone sufficient to reproduce the experimental area per lipid in constant-pressure simulations, and to produce a qualitatively correct lateral pressure profile.Comment: 24 pages, 7 figure

    Turner Syndrome Mosaicism 45,X/46,XY with Genital Ambiguity and Duchenne Muscular Dystrophy:Translational Approach of a Rare Italian Case

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    Turner syndrome (gonadal dysgenesis with short stature and sterility) is characterized by chromosomal karyotype 45,X in 50% of cases or by mosaicism (45,X/46,XX and 45,X/46,XY) in 30–40% or X structural defects (deletions, long arm isochromosome, ring chromosome). When mosaic Turner syndrome (TS) occurs with a Y chromosome, there may be ambiguous genitalia. Duchenne muscular dystrophy (DMD) is an inherited neuromuscular disease with an X-Linked recessive pattern of inheritance that predominantly affects males, while females are usually asymptomatic. DMD has also been observed in groups of females affected by TS, not homozygous for the mutation. Here, we report a case of an Indian neonate born with ambiguous genitalia diagnosed prenatally by ultrasound who had a karyotype of 45,X/46,XY and who also had Duchenne muscular dystrophy caused by a de novo mutation in the DMD gene. Physical examination was normal without the typical dysmorphic features of TS with the exception of the genitourinary system showing ambiguous genitalia. Gender was assigned as female. At the age of three years, she had increasing difficulty walking, running, jumping and climbing stairs, proximal upper and lower extremity muscle weakness and a positive Gowers’ sign. In addition, the serum creatine kinase (CK) value was over 30X the upper limit of normal. This study shows that DMD can occur in females with TS having 45,X/46,XY mosaicism and that this coexistence should be considered in women affected by TS who start to develop potential typical symptoms such as motor or developmental delay

    Laryngopharyngeal reflux diagnosis in obstructive sleep apnea patients using the pepsin salivary test

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    Background: To investigate the presence of laryngopharyngeal reflux in patients with obstructive sleep apnea (OSA) employing the salivary pepsin concentration method. To compare the results of pepsin concentration with the severity of the pathology. Methods: Seventy-five OSA patients (44 males, 31 females) were enrolled in the study. For each patient, the AHI (apnea–hypopnea index) and the BMI (body mass index) were initially evaluated. All the patients enrolled were assessed using the reflux symptom index (RSI) and the reflux finding score (RFS) in order to perform a clinical diagnosis of laryngopharyngeal reflux. In all patients a salivary sample was taken to estimate the presence of pepsin and its concentration. Results: The incidence of LPR (laryngopharyngeal reflux) in OSA patients, evaluated using the salivary pepsin concentration test (PEP-test), was found to be 32% of cases. Linear regression testing did not show any correlation between AHI and pepsin concentration in salivary samples (p = 0.1). Conclusion: A high number of patients with OSA seem to show positivity for salivary pepsin, correlated to an LPR. There does not appear to be a correlation between the severity of apnea and the grade of salivary pepsin reflux. On the other hand, direct correlation between BMI and the value of pepsin in salivary specimens was observed

    A Novel Smad7 Genetic Variant Mapping on the Genomic Region Targeted by Mongersen Is Associated with Crohn's Disease

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    Down-regulation of Smad7 with a specific Smad7 antisense (AS) oligonucleotide-containing oral drug (Mongersen) was effective in pre-clinical studies and initial clinical trials in Crohn's disease (CD) patients. A recent phase 3 trial was discontinued due to an apparent inefficacy of the drug, but factors contributing to the failure of this study remain unknown. Here, we analysed the frequency in CD of rs144204026 C/T single nucleotide polymorphism (SNP), which maps on the corresponding region targeted by the Smad7 AS contained in the Mongersen formulation and examined whether such a variant allele affects the ability of Smad7 AS to knockdown Smad7

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

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    A measurement of the production cross-section for top quark pairs(\ttbar) in pppp 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 ee or muon μ\mu) with large missing transverse energy and at least four jets, and dilepton (eeee, μμ\mu\mu or eμe\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±3.912.2 \pm 3.9 events and 2.5±0.62.5 \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

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

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    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
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