705 research outputs found

    Structure of 55Sc and development of the N=34 subshell closure

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    The low-lying structure of 55^{55}Sc has been investigated using in-beam γ\gamma-ray spectroscopy with the 9^{9}Be(56^{56}Ti,55^{55}Sc+γ\gamma)XX one-proton removal and 9^{9}Be(55^{55}Sc,55^{55}Sc+γ\gamma)XX inelastic-scattering reactions at the RIKEN Radioactive Isotope Beam Factory. Transitions with energies of 572(4), 695(5), 1539(10), 1730(20), 1854(27), 2091(19), 2452(26), and 3241(39) keV are reported, and a level scheme has been constructed using γγ\gamma\gamma coincidence relationships and γ\gamma-ray relative intensities. The results are compared to large-scale shell-model calculations in the sdsd-pfpf model space, which account for positive-parity states from proton-hole cross-shell excitations, and to it ab initio shell-model calculations from the in-medium similarity renormalization group that includes three-nucleon forces explicitly. The results of proton-removal reaction theory with the eikonal model approach were adopted to aid identification of positive-parity states in the level scheme; experimental counterparts of theoretical 1/21+1/2^{+}_{1} and 3/21+3/2^{+}_{1} states are suggested from measured decay patterns. The energy of the first 3/23/2^{-} state, which is sensitive to the neutron shell gap at the Fermi surface, was determined. The result indicates a rapid weakening of the N=34N=34 subshell closure in pfpf-shell nuclei at Z>20Z>20, even when only a single proton occupies the πf7/2\pi f_{7/2} orbital

    Shape evolution in 116,118 Ru: Triaxiality and transition between the O(6) and U(5) dynamical symmetries

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    116Ru and 118Ru have been studied via β-delayed γ-ray spectroscopy of nuclei produced in fragmentation reactions at the Radioactive Ion-Beam Factory (RIBF) facility. Level schemes with positive-parity states up to spin J=6 have been constructed. The re

    PTTG1-interacting protein (PTTG1IP/PBF) predicts breast cancer survival

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    Background: PTTG1-interacting protein (PTTG1IP) is an oncogenic protein, which participates in metaphase-anaphase transition of the cell cycle through activation of securin (PTTG1). PTTG1IP promotes the shift of securin from the cell cytoplasm to the nucleus, allowing the interaction between separase and securin. PTTG1IP overexpression has been previously observed in malignant disease, e.g. in breast carcinoma. However, the prognostic value of PTTG1IP in breast carcinoma patients has not previously been revealed.Methods: A total of 497 breast carcinoma patients with up to 22-year follow-up were analysed for PTTG1IP and securin immunoexpression. The results were evaluated for correlations with the clinical prognosticators and patient survival.Results: In our material, negative PTTG1IP immunoexpression predicted a 1.5-fold risk of breast cancer death (p = 0.02). However, adding securin immunoexpression to the analysis indicated an even stronger and independent prognostic power in the patient material (HR = 2.5, p < 0.0001). The subcellular location of securin was found with potential prognostic value also among the triple-negative breast carcinomas (n = 96, p = 0.052).Conclusions: PTTG1IP-negativity alone and in combination with high securin immunoexpression indicates a high risk of breast cancer death, resulting in up to 14-year survival difference in our material

    Central Pb+Pb Collisions at 158 A GeV/c Studied by Pion-Pion Interferometry

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    Two-particle correlations have been measured for identified negative pions from central 158 AGeV Pb+Pb collisions and fitted radii of about 7 fm in all dimensions have been obtained. A multi-dimensional study of the radii as a function of kT is presented, including a full correction for the resolution effects of the apparatus. The cross term Rout-long of the standard fit in the Longitudinally CoMoving System (LCMS) and the vl parameter of the generalised Yano-Koonin fit are compatible with 0, suggesting that the source undergoes a boost invariant expansion. The shapes of the correlation functions in Qinv and Qspace have been analyzed in detail. They are not Gaussian but better represented by exponentials. As a consequence, fitting Gaussians to these correlation functions may produce different radii depending on the acceptance of the experimental setup used for the measurement.Comment: 13 pages including 10 figure

    Search for Disoriented Chiral Condensates in 158 AGeV Pb+Pb Collisions

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    The restoration of chiral symmetry and its subsequent breaking through a phase transition has been predicted to create regions of Disoriented Chiral Condensates (DCC). This phenomenon has been predicted to cause anomalous fluctuations in the relative production of charged and neutral pions in high-energy hadronic and nuclear collisions. The WA98 experiment has been used to measure charged and photon multiplicities in the central region of 158 AGeV Pb+Pb collisions at the CERN SPS. In a sample of 212646 events, no clear DCC signal can be distinguished. Using a simple DCC model, we have set a 90% C.L. upper limit on the maximum DCC production allowed by the data.Comment: 20 Pages, LaTeX, uses elsart.cls, 8 eps figures included, submitted to Physics Letters

    Bcl-2 protein family: Implications in vascular apoptosis and atherosclerosis

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    Apoptosis has been recognized as a central component in the pathogenesis of atherosclerosis, in addition to the other human pathologies such as cancer and diabetes. The pathophysiology of atherosclerosis is complex, involving both apoptosis and proliferation at different phases of its progression. Oxidative modification of lipids and inflammation differentially regulate the apoptotic and proliferative responses of vascular cells during progression of the atherosclerotic lesion. Bcl-2 proteins act as the major regulators of extrinsic and intrinsic apoptosis signalling pathways and more recently it has become evident that they mediate the apoptotic response of vascular cells in response to oxidation and inflammation either in a provocative or an inhibitory mode of action. Here we address Bcl-2 proteins as major therapeutic targets for the treatment of atherosclerosis and underscore the need for the novel preventive and therapeutic interventions against atherosclerosis, which should be designed in the light of molecular mechanisms regulating apoptosis of vascular cells in atherosclerotic lesions

    A multilab study of bilingual infants: Exploring the preference for infant-directed speech

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    From the earliest months of life, infants prefer listening to and learn better from infant-directed speech (IDS) than adult-directed speech (ADS). Yet, IDS differs within communities, across languages, and across cultures, both in form and in prevalence. This large-scale, multi-site study used the diversity of bilingual infant experiences to explore the impact of different types of linguistic experience on infants’ IDS preference. As part of the multi-lab ManyBabies project, we compared lab-matched samples of 333 bilingual and 385 monolingual infants’ preference for North-American English IDS (cf. ManyBabies Consortium, in press (MB1)), tested in 17 labs in 7 countries. Those infants were tested in two age groups: 6–9 months (the younger sample) and 12–15 months (the older sample). We found that bilingual and monolingual infants both preferred IDS to ADS, and did not differ in terms of the overall magnitude of this preference. However, amongst bilingual infants who were acquiring North-American English (NAE) as a native language, greater exposure to NAE was associated with a stronger IDS preference, extending the previous finding from MB1 that monolinguals learning NAE as a native language showed a stronger preference than infants unexposed to NAE. Together, our findings indicate that IDS preference likely makes a similar contribution to monolingual and bilingual development, and that infants are exquisitely sensitive to the nature and frequency of different types of language input in their early environments
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