The recently proposed combination of the valence-space in-medium similarity renormalization group (VS-IMSRG) with the density matrix renormalization group (DMRG) offers a scalable and flexible ...many-body approach for strongly correlated open-shell nuclei. We use the VS-DMRG to investigate the low-lying spectroscopy of N=50 isotones, which are characteristic for their transition between single-particle and collective excitations. We also study electromagnetic transitions and show the advantage of the VS-DMRG to capture the underlying physics more efficiently, with significantly improved convergence compared to state-of-the-art shell-model truncations. Combined with an analysis of quantum information measures, this further establishes the VS-DMRG as a valuable method for ab initio calculations of nuclei.
We investigate the effects of two-body currents on magnetic dipole moments of medium-mass and heavy nuclei using the valence-space in-medium similarity renormalization group with chiral effective ...field theory interactions and currents. Focusing on near doubly magic nuclei from oxygen to bismuth, we have found that the leading two-body currents globally improve the agreement with experimental magnetic moments. Moreover, our results show the importance of multishell effects for Ca 41 , which suggest that the Z = N = 20 gap in Ca 40 is not as robust as in Ca 48 . The increasing contribution of two-body currents in heavier systems is explained by the operator structure of the center-of-mass dependent Sachs term. Published by the American Physical Society 2024
Since the 26 December 2004 Indian Ocean tsunami, the role of mangrove forests as natural defenses protecting coastal communities from tsunami disaster has been highlighted. However, some mangrove ...forests were destroyed by that tsunami. They are expected to have lost their protective functions. In this study, we develop a fragility function to assess the mangrove trees' vulnerability, expressed as the damage probability of mangrove trees, based on field surveys and numerical modeling of the 2004 Indian Ocean tsunami in Banda Aceh, Indonesia. Based on the fragility function, we reconstruct a numerical model of tsunami inundation including the performance of mangrove forests in terms of reducing tsunami damage. The model reveals that a 10 year old mangrove forest in a 500 m wide area can reduce a tsunami's hydrodynamic force by approximately 70% for an incident wave of 3.0 m inundation depth and a wave period of 40 min at the shoreline. The model also shows, for a tsunami inundation depth of greater than 4 m, that a 10 year old mangrove forest would be mostly destroyed and that it would lose its force reduction capacity. Moreover, approximately 80% of a 30 year old mangrove forest would survive a 5 m tsunami and absorb 50% of the tsunami's hydrodynamic force.
We previously found an inverse relationship between sialidase Neu1 expression and metastatic potential of marine cancer cells. To elucidate the mechanism underlying the cellular events, the human ...sialidase gene NEV1 was overexpressed or silenced in colon cancer HT-29 cells. When NEU1-overexpressing cells were injected transsplenically into mice, in vivo liver metastasis was significantly reduced. NEU1 suppressed cell migration, invasion and adhesion in vitro, whereas the silencing resulted in the opposite. One of the major molecular changes by NEU1 was decreased sialylation of integrin β4, assessed by PNA-and MAL-II-lectin blotting of immunoprecipitates with anti-integrin β4 antibody. The desialylation was accompanied by decreased phosphorylation of the integrin followed by attenuation of focal adhesion kinase and Erk1/2 pathway. Moreover, NEU1 caused downregulation of matrix metalloproteinase-7, overexpression of which is associated with cancer metastasis. Treatment of the cells with Ga1NAc-α-O-benzyl, an inhibitor of O-glycosylation, showed increased PNA-positive integrin β4 with its decreased phosphorylation, indicating that sialic acid removal from the integrin O-glycans results in the decreased phosphorylation. Biotinylation and immunofluorescence staining exhibited some NEU1 molecules to be at the cell surface accessible to the integrin. These results suggest that NEU1 is important in regulation of integrin β4-mediated signaling, leading to suppression of metastasis. doi:10.1038/onc.2008.471; published online 19 January 2009 Keywords: sialidase; integrin (34; sialic acid; metastasis; invasion; MMP-7
We present converged ab initio calculations of structure factors for elastic spin-dependent WIMP scattering off all nuclei used in dark matter direct-detection searches: ^{19}F, ^{23}Na, ^{27}Al, ...^{29}Si, ^{73}Ge, ^{127}I, and ^{129,131}Xe. From a set of established two- and three-nucleon interactions derived within chiral effective field theory, we construct consistent WIMP-nucleon currents at the one-body level, including effects from axial-vector two-body currents. We then apply the in-medium similarity renormalization group to construct effective valence-space Hamiltonians and consistently transformed operators of nuclear responses. Combining the recent advances of natural orbitals with three-nucleon forces expressed in large spaces, we obtain basis-space converged structure factors even in heavy nuclei. Generally results are consistent with previous calculations but large uncertainties in ^{127}I highlight the need for further study.
Mass measurements continue to provide invaluable information for elucidating nuclear structure and scenarios of astrophysical interest. The transition region between the Z=20 and 28 proton shell ...closures is particularly interesting due to the onset and evolution of nuclear deformation as nuclei become more neutron-rich. This provides a critical testing ground for emerging ab-initio nuclear structure models. Here, we present high-precision mass measurements of neutron-rich chromium isotopes using the sensitive electrostatic Multiple-Reflection Time-Of-Flight Mass Spectrometer (MR-TOF-MS) at TRIUMF's Ion Trap for Atomic and Nuclear Science (TITAN) facility. Our high-precision mass measurements of 59,61−63Cr confirm previous results, and the improved precision in measurements of 64−65Cr refine the mass surface beyond N=40. With the ab initio in-medium similarity renormalization group, we examine the trends in collectivity in chromium isotopes and give a complete picture of the N=40 island of inversion from calcium to nickel.
Summary
Background
Taxanes are the current first‐line treatment for advanced cutaneous angiosarcoma (CAS) for patients who are considered difficult to treat with doxorubicin owing to advanced age or ...comorbidity. However, no effective second‐line therapy for such patients has been established.
Methods
We designed a single‐arm prospective observational study of eribulin mesylate (ERB) administered at a dose of 1·4 mg m−2 on days 1 and 8 in a 21‐day cycle. Patients with advanced CAS who were previously treated with a taxane and were scheduled to begin ERB treatment were enrolled. The primary endpoint was overall survival (OS) and the secondary endpoints were response rate (RR), progression‐free survival (PFS) and toxicity assessment.
Results
We enrolled a total of 25 patients. The median OS and PFS were 8·6 months and 3·0 months, respectively. The best overall RR was 20% (five of 25). In total, 16 grade 3/4 severe adverse events (SAEs) occurred; however, all patients recovered. Patients who achieved partial response or stable disease as best response had longer OS than those with progressive disease (median OS not reached and 3·3 months, respectively; P < 0·001). Patients who did not experience SAEs showed longer OS than those who did (median OS 18·8 months and 7·5 months, respectively; P < 0·05). Patients with distant metastasis had shorter median OS than those with locoregional disease, but without statistically significant difference.
Conclusions
ERB showed a promising RR and is a potential candidate for second‐line treatment for patients with CAS, after treatment with taxanes. However, owing to the occurrence of SAEs in over half of the participants, caution should be exercised regarding ERB use in elderly patients.
What is already known about this topic?
Taxanes are the current first‐line treatment for patients with advanced cutaneous angiosarcoma (CAS) who are considered difficult to treat with doxorubicin owing to advanced age or comorbidity.
No effective therapy for taxane‐resistant CAS has been established thus far.
Eribulin suppresses microtubule polymerization and elicits an antitumour effect similar to that of taxanes.
What does this study add?
In our single‐arm prospective observational study to evaluate the efficacy of eribulin for treating patients with advanced CAS who previously received taxanes, the median overall survival and progression‐free survival were 8·6 and 3·0 months, respectively.
Response rates at weeks 7, 13 and 25 were 20%, 17% and 14%, respectively.
Although 16 grade 3/4 severe adverse events occurred, all patients recovered.
Eribulin showed a promising response rate and is a potential candidate for second‐line treatment in CAS after taxane treatment.
Linked Comment: Smrke and Benson. Br J Dermatol 2020; 183:797–798.
What is already known about this topic?
Taxanes are the current first‐line treatment for patients with advanced cutaneous angiosarcoma (CAS) who are considered difficult to treat with doxorubicin owing to advanced age or comorbidity.
No effective therapy for taxane‐resistant CAS has been established thus far.
Eribulin suppresses microtubule polymerization and elicits an antitumour effect similar to that of taxanes.
What does this study add?
In our single‐arm prospective observational study to evaluate the efficacy of eribulin for treating patients with advanced CAS who previously received taxanes, the median overall survival and progression‐free survival were 8·6 and 3·0 months, respectively.
Response rates at weeks 7, 13 and 25 were 20%, 17% and 14%, respectively.
Although 16 grade 3/4 severe adverse events occurred, all patients recovered.
Eribulin showed a promising response rate and is a potential candidate for second‐line treatment in CAS after taxane treatment.
Linked Comment: Smrke and Benson. Br J Dermatol 2020; 183:797–798.
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