We extend the formalism of self-consistent Green's function theory to include three-body interactions and apply it to isotopic chains around oxygen for the first time. The third-order algebraic ...diagrammatic construction equations for two-body Hamiltonians can be exploited upon defining system-dependent one- and two-body interactions coming from the three-body force, and, correspondingly, dropping interaction-reducible diagrams. The Koltun sum rule for the total binding energy acquires a correction due to the added three-body interaction. This formalism is then applied to study chiral two- and three-nucleon forces evolved to low momentum cutoffs. The binding energies of nitrogen, oxygen, and fluorine isotopes are reproduced with good accuracy and demonstrate the predictive power of this approach. Leading order three-nucleon forces consistently bring results close to the experiment for all neutron rich isotopes considered and reproduce the correct driplines for oxygen and nitrogen. The formalism introduced also allows us to calculate form factors for nucleon transfer on doubly magic systems.
The recently confirmed neutron-shell closure at N=32 has been investigated for the first time below the magic proton number Z=20 with mass measurements of the exotic isotopes (52,53)K, the latter ...being the shortest-lived nuclide investigated at the online mass spectrometer ISOLTRAP. The resulting two-neutron separation energies reveal a 3 MeV shell gap at N=32, slightly lower than for 52Ca, highlighting the doubly magic nature of this nuclide. Skyrme-Hartree-Fock-Bogoliubov and ab initio Gorkov-Green function calculations are challenged by the new measurements but reproduce qualitatively the observed shell effect.
Single nucleon pickup reactions were performed with a 18.1 MeV/nucleon (14)O beam on a deuterium target. Within the coupled reaction channel framework, the measured cross sections were compared to ...theoretical predictions and analyzed using both phenomenological and microscopic overlap functions. The missing strength due to correlations does not show significant dependence on the nucleon separation energy asymmetry over a wide range of 37 MeV, in contrast with nucleon removal data analyzed within the sudden-eikonal formalism.
Overexpression of the transmembrane sialomucin podocalyxin, which is known to play a role in lumen formation during polarized epithelial morphogenesis, is an independent indicator of poor prognosis ...in a number of epithelial cancers, including those that arise in the breast. Therefore, we set out to determine if podocalyxin plays a functional role in breast tumor progression.
MCF-7 breast cancer cells, which express little endogenous podocalyxin, were stably transfected with wild type podocalyxin for forced overexpression. 4T1 mammary tumor cells, which express considerable endogenous podocalyxin, were retrovirally transduced with a short hairpin ribonucleic acid (shRNA) targeting podocalyxin for stable knockdown. In vitro, the effects of podocalyxin on collective cellular migration and invasion were assessed in two-dimensional monolayer and three-dimensional basement membrane/collagen gel culture, respectively. In vivo, local invasion was assessed after orthotopic transplantation in immunocompromised mice.
Forced overexpression of podocalyxin caused cohesive clusters of epithelial MCF-7 breast tumor cells to bud off from the primary tumor and collectively invade the stroma of the mouse mammary gland in vivo. This budding was not associated with any obvious changes in histoarchitecture, matrix deposition or proliferation in the primary tumour. In vitro, podocalyxin overexpression induced a collective migration of MCF-7 tumor cells in two-dimensional (2-D) monolayer culture that was dependent on the activity of the actin scaffolding protein ezrin, a cytoplasmic binding partner of podocalyxin. In three-dimensional (3-D) culture, podocalyxin overexpression induced a collective budding and invasion that was dependent on actomyosin contractility. Interestingly, the collectively invasive cell aggregates often contained expanded microlumens that were also observed in vivo. Conversely, when endogenous podocalyxin was removed from highly metastatic, but cohesive, 4T1 mammary tumor cells there was a decrease in collective invasion in three-dimensional culture.
Podocalyxin is a tumor cell-intrinsic regulator of experimental collective tumor cell invasion and tumor budding.
The model of Nambu and Jona-Lasinio has been extensively used to model the possible occurrence of quark matter in the core of compact stars. While based entirely on similar physical assumptions, ...previous studies have been performed using a variety of model versions, differing in both the number of active quark flavors and the structure of the quark-quark interaction. We discuss the results of our systematic analysis, designed to clarify the role of the vector and instanton-induced interactions in determining the properties of hybrid stars. The results of our calculations, carried out using a state-of-the-art description of the hadronic phase, show that the instanton-induced interaction does not affect the stiffness of the quark matter equation of state, whereas the effect of the repulsive vector interaction is sizable. However, no values of the corresponding coupling constants allow for the formation of a stable core of quark matter.
High grade serous ovarian tumors often metastasize transperitoneally, a process that begins when small tumor nodules de-adhere and are released into the fluid of the abdominal cavity where they float ...freely to reach new sites on the peritoneal wall. Podocalyxin, a small anti-adhesive sialomucin, has been shown to contribute to non-adhesive membrane domain formation in some epithelia and is overexpressed in a variety of cancers. We therefore assessed podocalyxin expression on a previously characterized tissue microarray and found that 87% (169/194) of high grade serous epithelial ovarian carcinomas were positive for podocalyxin. In addition, cell surface localization of podocalyxin was associated with a significant decrease in disease-free survival in these tumors. When podocalyxin was force-expressed in serous ovarian carcinoma-derived OVCAR-3 cells it was targeted to the cell surface and it decreased the adhesion of these cells to mesothelial monolayers, fibronectin and immobilized β1 integrin-binding antibodies. This decrease in adhesion was associated with a modest decrease in cell surface β1 integrin. In monolayer culture, podocalyxin was targeted to the free, apical domains of OVCAR-3 cells and it appeared to decrease β1 integrin levels on the attached basolateral domains of the same cells. Furthermore, in 3-dimensional basement membrane gel culture, the cells formed small, cohesive nodules and podocalyxin localized to membrane domains at the cell–basement membrane interface. Therefore, podocalyxin’s ability to facilitate the formation of non-adhesive membrane domains may contribute to the formation of free-floating high grade serous tumor nodules during the initial steps of transperitoneal metastasis.
Aim of this literature overview was to analyze the diagnostic procedures of hidden caries lesions and to present a restorative protocol.
A literature overview was performed in order to evaluate ...hidden caries etiological hypothesis and the reported prevalence. The diagnostic procedure is performed with the aid of an intra-oral fluorescence based camera and the restorative procedure is completed with the use of a novel bisphenol-A free composite.
Non cavitated occlusal caries lesions prevalence is high in young adults population. Diagnosis of hidden caries requires both high sensitivity and specificity.
The novel diagnostic and restorative protocol showed to be highly effective in hidden caries assessment and restoration.
Advances in the self-consistent Green's function approach to finite nuclei are discussed, including the implementation of three-nucleon forces and the extension to the Gorkov formalism. We report ...results on binding energies in the nitrogen and fluorine isotopic chains, as well as spectral functions of super(22)O. The application to medium-mass open-shell systems is illustrated by separation energy spectra of two argon isotopes, which are compared to one-neutron removal experiments.
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