1,569 research outputs found
On the solar origin of the 200 y Suess wiggles: Evidence from thermoluminescence in sea sediments
In order to understand the origin of the Suess wiggles, present in the tree ring 14C record, we have studied the thermoluminescence (TL) of a shallow-water Ionian sea core, in an attempt to provide a record of an indicator
responding to the solar output more promptly than 14C in tree rings. The spectral content of the TL and radiocarbon records is very similar; neverthless, in addition to the 207 y Suess wave (A43.6% ), the TL record shows the second harmonic (103.5 y; A42.4% ), in phase with the envelope of the 11 y solar cycles. This result, obtained by different spectral methods, in particular by Superposition of Epochs (SE) and by Singular Spectrum Analysis (SSA), strongly supports the solar origin of the 200 y Suess wiggles
The three-body recombination of a condensed Bose gas near a Feshbach resonance
In this paper, we study the three-body recombination rate of a homogeneous
dilute Bose gas with a Feshbach resonance at zero temperature. The ground state
and excitations of this system are obtained. The three-body recombination in
the ground state is due to the break-up of an atom pair in the quantum
depletion and the formation of a molecule by an atom from the broken pair and
an atom from the condensate. The rate of this process is in good agreement with
the experiment on Na in a wide range of magnetic fields.Comment: 10 pages, 2 figures, to be published in Phys. Rev.
Multiphysics analyses of the effect of package on the performances of PMUT transducers
The paper deals with the multiphysics modeling of piezoelectric micromachined ultrasound transducers (PMUT), that can be used in several practical applications. The model accounts for the multiple couplings between the mechanical fields and the electric and acoustic ones. The numerical solution has been sought by means of the finite element method, for the special case of axial symmetry. The model has been validated with reference to experimental data, that have been obtained by the Authors. The numerical procedure has been applied to carry out a parametric analysis of the effect of package, to extract a set of design guidelines
CP-odd static electromagnetic properties of the W gauge boson and the t quark via the anomalous tbW coupling
In the framework of the electroweak chiral Lagrangian, the one-loop induced
effects of the anomalous coupling, which includes both left- and
right-handed complex components, on the static electromagnetic properties of
the boson and the quark are studied. The attention is focused mainly on
the CP-violating electromagnetic properties. It is found that the
anomalous coupling can induce both CP-violating moments of the boson,
namely, its electric dipole () and magnetic quadrupole
() moments. As far as the quark is concerned, a potentially
large electric dipole moment can arise due to the anomalous
coupling. The most recent bounds on the left- and right-handed parameters from
meson physics lead to the following estimates e-cm and e-cm, which
are 7 and 14 orders of magnitude larger than the standard model (SM)
predictions, whereas may be as large as e-cm, which is about 8
orders of magnitude larger than its SM counterpart.Comment: This paper has been merged with hep-ph/0612171 for publication in
Physical Review
Costs of managing adverse events in the treatment of first-line metastatic renal cell carcinoma: Bevacizumab in combination with interferon-α2a compared with sunitinib
Background: Bevacizumab plus interferon-α2a (IFN) prolongs progression-free survival to>10 months, which is comparable with sunitinib as first-line treatment of metastatic renal cell carcinoma (RCC). The two regimens have different tolerability profiles; therefore, costs for managing adverse events may be an important factor in selecting therapy.Methods: Costs of managing adverse events affecting patients with metastatic RCC eligible for treatment with bevacizumab plus IFN or sunitinib were evaluated using a linear decision analytical model. Management costs were calculated from the published incidence of adverse events and health-care costs for treating adverse events in the United Kingdom, Germany, France and Italy.Results: Adverse event management costs were higher for sunitinib than for bevacizumab plus IFN. The average cost per patient for the management of grade 3-4 adverse events was markedly lower with bevacizumab plus IFN compared with sunitinib in the United Kingdom (\[euro]1475 vs \[euro]804), Germany (\[euro]1785 vs \[euro]1367), France (\[euro]2590 vs \[euro]1618) and Italy (\[euro]891 vs \[euro]402). The main cost drivers were lymphopaenia, neutropaenia, thrombocytopaenia, leucopaenia and fatigue/asthaenia for sunitinib; and proteinuria, fatigue/asthaenia, bleeding, anaemia and gastrointestinal perforation for bevacizumab plus IFN.Conclusion: The costs of managing adverse events are lower for bevacizumab plus IFN than for sunitinib. The potential for cost savings should be considered when selecting treatments for RCC
Real-world efficacy and safety of nivolumab in previously-treated metastatic renal cell carcinoma, and association between immune-related adverse events and survival: the Italian expanded access program
Background: The Italian Renal Cell Cancer Early Access Program was an expanded access program that allowed access to nivolumab, for patients (pts) with metastatic renal cell carcinoma (mRCC) prior to regulatory approval. Methods: Pts with previously treated advanced or mRCC were eligible to receive nivolumab 3 mg/kg every 2 weeks. Pts included in the analysis had received ≥1 dose of nivolumab and were monitored for drug-related adverse events (drAEs) using CTCAE v.4.0. Immune-related (ir) AEs were defined as AEs displaying a certain, likely or possible correlation with immunotherapy (cutaneous, endocrine, hepatic, gastro-intestinal and pulmonary). The association between overall survival (OS) and irAEs was assessed, and associations between variables were evaluated with a logistic regression model. Results: A total of 389 pts were enrolled between July 2015 and April 2016. Overall, the objective response rate was 23.1%. At a median follow-up of 12 months, the median progression-free survival was 4.5 months (95% CI 3.7-6.2) and the 12-month overall survival rate was 63%. Any grade and grade 3-4 drAEs were reported in 124 (32%) and 27 (7%) of pts, respectively, and there were no treatment-related deaths. Any grade irAEs occurred in 76 (20%) of patients, 8% cutaneous, 4% endocrine, 2% hepatic, 5% gastro-intestinal and 1% pulmonary. Of the 22 drAEs inducing treatment discontinuation, 10 (45%) were irAEs. Pts with drAEs had a significantly longer survival than those without drAEs (median OS 22.5 versus 16.4 months, p = 0.01). Pts with irAEs versus without irAEs had a more significant survival benefit (median OS not reached versus 16.8 months, p = 0.002), confirmed at the landmark analysis at 6 weeks. The occurrence of irAEs displayed a strong association with OS in univariable (HR 0.48, p = 0.003) and multivariable (HR 0.57, p = 0.02) analysis. Conclusions: The appearance of irAEs strongly correlates with survival benefit in a real-life population of mRCC pts treated with nivolumab
Casimir-like tunneling-induced electronic forces
We study the quantum forces that act between two nearby conductors due to
electronic tunneling. We derive an expression for these forces by calculating
the flux of momentum arising from the overlap of evanescent electronic fields.
Our result is written in terms of the electronic reflection amplitudes of the
conductors and it has the same structure as Lifshitz's formula for the
electromagnetically mediated Casimir forces. We evaluate the tunneling force
between two semiinfinite conductors and between two thin films separated by an
insulating gap. We discuss some applications of our results.Comment: 8 pages, 3 figs, submitted to Proc. of QFEXT'05, to be published in
J. Phys.
Combined use of x-ray fluorescence microscopy, phase contrast imaging for high resolution quantitative iron mapping in inflamed cells
X-ray fluorescence microscopy (XRFM) is a powerful technique to detect and localize elements in cells. To derive information useful for biology and medicine, it is essential not only to localize, but also to map quantitatively the element concentration. Here we applied quantitative XRFM to iron in phagocytic cells. Iron, a primary component of living cells, can become toxic when present in excess. In human fluids, free iron is maintained at 10-18 M concentration thanks to iron binding proteins as lactoferrin (Lf). The iron homeostasis, involving the physiological ratio of iron between tissues/secretions and blood, is strictly regulated by ferroportin, the sole protein able to export iron from cells to blood. Inflammatory processes induced by lipopolysaccharide (LPS) or bacterial pathoge inhibit ferroportin synthesis in epithelial and phagocytic cells thus hindering iron export, increasing intracellular iron and bacterial multiplication. In this respect, Lf is emerging as an important regulator of both iron and inflammatory homeostasis. Here we studied phagocytic cells inflamed by bacterial LPS and untreated or treated with milk derived bovine Lf. Quantitative mapping of iron concentration and mass fraction at high spatial resolution is obtained combining X-ray fluorescence microscopy, atomic force microscopy and synchrotron phase contrast imaging
- …
