552 research outputs found
Anomalous high activation energy for creep in nanostructured 3YTZP/Ni cermets
The plastic behavior of cermets based on a 3 mol% yttria-stabilized tetragonal zirconia matrix that incorporates nanometric nickel inclusions (3YTZP/n-Ni), with 2.5, 5 and 10 vol.% of nickel content, has been studied by constant load tests in compression carried out in argon atmosphere. The microstructure of these composites consists of nanometric nickel inclusions homogeneously dispersed into a fine-grained zirconia matrix (about 200 nm). The microstructural and mechanical results obtained show that the creep behavior is controlled by the zirconia matrix as in 3YTZP-based cermets with micrometric Ni inclusions (3YTZP/ÎŒ-Ni); whereas the stress exponent values are similar to those of high-purity monolithic 3YTZPs, anomalous high values of the activation energy have been measured. The ceramic/metal interface plays a crucial role for creep properties; the strong TZP/n-Ni interface matching can be at the origin of these high values of the activation energies for creep.Ministerio de EducaciĂłn y Ciencia MAT2003-04199-CO
Chromospheric polarimetry through multi-line observations of the 850 nm spectral region II: A magnetic flux tube scenario
In this publication we continue the work started in Quintero Noda et al.
(2017) examining this time a numerical simulation of a magnetic flux tube
concentration. Our goal is to study if the physical phenomena that take place
in it, in particular, the magnetic pumping, leaves a specific imprint on the
examined spectral lines. We find that the profiles from the interior of the
flux tube are periodically dopplershifted following an oscillation pattern that
is also reflected in the amplitude of the circular polarization signals. In
addition, we analyse the properties of the Stokes profiles at the edges of the
flux tube discovering the presence of linear polarization signals for the Ca II
lines, although they are weak with an amplitude around 0.5% of the continuum
intensity. Finally, we compute the response functions to perturbations in the
longitudinal field and we estimate the field strength using the weak field
approximation. Our results indicate that the height of formation of the
spectral lines changes during the magnetic pumping process which makes the
interpretation of the inferred magnetic field strength and its evolution more
difficult. These results complement those from previous works demonstrating the
capabilities and limitations of the 850 nm spectrum for chromospheric Zeeman
polarimetry in a very dynamic and complex atmosphere.Comment: 12 pages, 12 figures, 0 tables, MNRAS main journal publicatio
Randomized Phase II Trial of Sapanisertib ± TAK-117 vs. Everolimus in Patients With Advanced Renal Cell Carcinoma After VEGF-Targeted Therapy
MTOR inhibitors; Everolimus; Renal cell carcinomaInhibidores de MTOR; Everolimus; Carcinoma de células renalesInhibidors de MTOR; Everolimus; Carcinoma de cÚl·lules renalsBackground
Sapanisertib, a dual mTORC1/2 inhibitor, may offer more complete inhibition of the PI3K/AKT/mTOR pathway than mTORC1 inhibitors, such as everolimus. This phase II study evaluated the efficacy and safety of single-agent sapanisertib and sapanisertib plus the PI3Kα inhibitor TAK-117, vs. everolimus in patients with advanced clear cell renal cell carcinoma (ccRCC) that had progressed on or after VEGF-targeted therapy.
Materials and Methods
Patients with histologically confirmed, advanced ccRCC were randomized 1:1:1 to receive single-agent everolimus 10 mg once daily, single-agent sapanisertib 30 mg once weekly, or sapanisertib 4 mg plus TAK-117 200 mg, both once daily for 3 days/week, in 28-day cycles. The primary endpoint was progression-free survival (PFS).
Results
Ninety-five patients were treated with everolimus or sapanisertib (n = 32 each), or sapanisertib plus TAK-117 (n = 31). There were no significant differences in PFS among the 3 groups or across any subgroups. Median PFS was 3.8 months with everolimus vs. 3.6 months with sapanisertib (HR, 1.33; 95% CI, 0.75-2.36), and 3.1 months with sapanisertib plus TAK-117 (HR, 1.37; 95% CI, 0.75-2.52). No significant differences in overall survival were seen among groups. Overall response rate was 16.7%, 0%, and 7.1%, respectively. Discontinuations due to treatment-emergent adverse events were 15.6%, 28.1%, and 29.0%.
Conclusion
Sapanisertib with or without TAK-117 was less tolerable and did not improve efficacy vs. everolimus in patients with advanced ccRCC who had relapsed after or were refractory to VEGF-targeted therapies. Dual mTORC1/2 inhibition may not be an effective therapeutic approach for these patients.This article is supported by Takeda Development Center Americas, Inc., Lexington, MA, USA
Chromospheric polarimetry through multi-line observations of the 850 nm spectral region III: Chromospheric jets driven by twisted magnetic fields
We investigate the diagnostic potential of the spectral lines at 850 nm for
understanding the magnetism of the lower atmosphere. For that purpose, we use a
newly developed 3D simulation of a chromospheric jet to check the sensitivity
of the spectral lines to this phenomenon as well as our ability to infer the
atmospheric information through spectropolarimetric inversions of noisy
synthetic data. We start comparing the benefits of inverting the entire
spectrum at 850 nm versus only the Ca II 8542 A spectral line. We found a
better match of the input atmosphere for the former case, mainly at lower
heights. However, the results at higher layers were not accurate. After several
tests, we determined that we need to weight more the chromospheric lines than
the photospheric ones in the computation of the goodness of the fit. The new
inversion configuration allows us to obtain better fits and consequently more
accurate physical parameters. Therefore, to extract the most from multi-line
inversions, a proper set of weights needs to be estimated. Besides that, we
conclude again that the lines at 850 nm, or a similar arrangement with Ca II
8542 A plus Zeeman sensitive photospheric lines, poses the best observing
configuration for examining the thermal and magnetic properties of the lower
solar atmosphere.Comment: 14 pages, 11 figure
Grade 3/4 Adverse Event Costs of Immuno-oncology Combination Therapies for Previously Untreated Advanced Renal Cell Carcinoma
Advanced renal cell carcinoma; Adverse event cost; Nivolumab plus cabozantinibCarcinoma de células renales avanzado; Coste de eventos adversos; Nivolumab mås cabozantinibCarcinoma de cÚl·lules renals avançat; Cost d'esdeveniments adversos; Nivolumab més cabozantinibBackground
Despite 4 approved combination regimens in the first-line setting for advanced renal cell carcinoma (aRCC), adverse event (AE) costs data are lacking.
Materials and Methods
A descriptive analysis on 2 AE cost comparisons was conducted using patient-level data for the nivolumab-based therapies and published data for the pembrolizumab-based therapies. First, grade 3/4 AE costs were compared between nivolumabâ
+â
ipilimumab vs. nivolumabâ
+â
cabozantinib vs. pembrolizumabâ
+â
axitinib using data from the CheckMate 214 (median follow-up [mFU]: 13.1 months), CheckMate 9ER (mFU: 12.8 months), and KEYNOTE-426 (mFU: 12.8 months) trials, respectively. Second, grade 3/4 AE costs were compared between nivolumabâ
+â
ipilimumab vs. nivolumabâ
+â
cabozantinib vs. pembrolizumabâ
+â
lenvatinib using data from the CheckMate 214 (mFU: 26.7 months), CheckMate 9ER (mFU: 23.5 months), and KEYNOTE-581 (mFU: 26.6 months) trials, respectively. Per-patient costs for all-cause and treatment-related grade 3/4 AEs with corresponding any-grade AE ratesâ
â„â
20% were calculated based on the Healthcare Cost and Utilization Project database and inflated to 2020 US dollars.
Results
Per-patient all-cause grade 3/4 AE costs for nivolumabâ
+â
ipilimumab vs. nivolumabâ
+â
cabozantinib vs. pembrolizumabâ
+â
axitinib were 4508 vs. 741 vs. 4440 over ~12.8 months of FU. For nivolumabâ
+â
ipilimumab vs. nivolumabâ
+â
cabozantinib vs. pembrolizumabâ
+â
lenvatinib, per-patient all-cause grade 3/4 AE costs were 5800 vs. 863 vs. 5030 over ~26.6 months of FU.
Conclusion
Patients with aRCC treated with first-line nivolumab-based therapies had lower grade 3/4 all-cause and treatment-related AE costs than pembrolizumab-based therapies, suggesting a more favorable cost-benefit profile.This study was funded by Bristol Myers Squibb
Temporal Trends in Grade 3/4 Adverse Events and Associated Costs of Nivolumab Plus Cabozantinib Versus Sunitinib for Previously Untreated Advanced Renal Cell Carcinoma
Advanced Renal Cell Carcinoma; Adverse Events; NivolumabCarcinoma de células renales avanzado; Eventos adversos; NivolumabCarcinoma de cÚl·lules renals avançat; Esdeveniments adversos; NivolumabBackground and Objectives
Novel immunotherapy-based combination treatments have drastically improved clinical outcomes for previously untreated patients with advanced/metastatic renal cell carcinoma (aRCC). This study aimed to assess the temporal trends in grade 3/4 adverse event (AE) rates and associated costs of nivolumab plus cabozantinib combination therapy versus sunitinib monotherapy in previously untreated patients with aRCC.
Methods
Individual patient data from the CheckMate 9ER trial (nivolumab plus cabozantinib: N = 320; sunitinib: N = 320) were used to calculate the proportion of patients experiencing grade 3/4 AEs. AE unit costs were obtained from the United States (US) 2017 Healthcare Cost and Utilization Project (HCUP) and inflated to 2020 US dollars. Per-patient-per-month (PPPM) all-cause and treatment-related grade 3/4 AE costs over 18-months, temporal trends, and top drivers of AE costs were evaluated in both treatment arms.
Results
Overall, the proportion of patients experiencing grade 3/4 AEs decreased over time, with the highest rates observed in the first 3 months for the nivolumab plus cabozantinib and sunitinib arms. Compared with sunitinib, nivolumab plus cabozantinib was associated with consistently lower average all-cause AE costs PPPM [month 3: 3097 (p 0.05); month 18: 1755 (p > 0.05)]. Over 18 months, metabolism and nutrition disorders (182), and general disorders and administration site conditions (443), blood and lymphatic system disorders (177) were the costliest in the sunitinib arm. Trends of treatment-related AE costs were consistent with all-cause AE costs.
Conclusions
Nivolumab plus cabozantinib was associated with lower costs of grade 3/4 AE management PPPM than sunitinib, which accumulated over the 18-month study period
Defensive Strategy and Player Sex Impact Heart-Rate Responses During Games-Based Drills in Professional Basketball
[EN] Purpose: Games-based drills (GBD) are the predominant form of training stimulus prescribed to male and female basketball
players. Despite being readily manipulated during GBD, the impact of defensive strategy on the sex-specific demands of GBD
remains unknown. Therefore, the aim of this study was to quantify and compare the heart-rate (HR) responses experienced during
5v5 GBD using different defensive strategies (man-to-man defense vs zone defense [ZD] formations) according to player sex.
Method: HR was recorded in 11 professional male and 10 professional female basketball players while performing 5v5 GBD
with different defensive strategies (man-to-man defense or ZD). HR-based training load was also calculated using the summated
heart-rate zones model. Results: During man-to-man defense, mean HR (η2p
= .02), relative time (in percentage) spent working at
90% to 100% maximal HR (η2p
= .03), and summated heart-rate zones (η2p
= .02) were greater (P < .05) in female players
compared with males. During ZD, higher (P < .01) peak HR (η2p
= .07), mean HR (η2p
= .11), relative and absolute (in minutes)
time spent working at 80% to 89% maximal HR (η2p
= .03 and .03, respectively) and 90% to 100% maximal HR (η2p
= .12 and .09,
respectively), and summated heart-rate zones (η2p
= .19) were observed in female players compared with males. Conclusions:
The defensive strategy employed during 5v5 full-court GBD influences HR responses and training load differently according to
sex, where female players experience higher HR responses than males, especially when ZD are adopted. Basketball coaching
staff can use these findings for the precise manipulation of team defenses during GBD to elicit desired cardiovascular stress on
players
Bose-Einstein condensate dark matter phase transition from finite temperature symmetry breaking of Klein-Gordon fields
In this paper the thermal evolution of scalar field dark matter particles at
finite cosmological temperatures is studied. Starting with a real scalar field
in a thermal bath and using the one loop quantum corrections potential, we
rewrite Klein-Gordon's (KG) equation in its hydrodynamical representation and
study the phase transition of this scalar field due to a Z_2 symmetry breaking
of its potential. A very general version of a nonlinear Schr\"odinger equation
is obtained. When introducing Madelung's representation, the continuity and
momentum equations for a non-ideal SFDM fluid are formulated, and the
cosmological scenario with the SFDM described in analogy to an imperfect fluid
is then considered where dissipative contributions are obtained in a natural
way.Additional terms appear compared to those obtained in the classical version
commonly used to describe the \LambdaCDM model, i.e., the ideal fluid. The
equations and parameters that characterize the physical properties of the
system such as its energy, momentum and viscous flow are related to the
temperature of the system, scale factor, Hubble's expansion parameter and the
matter energy density. Finally, some details on how galaxy halos and smaller
structures might be able to form by condensation of this SF are given.Comment: Substantial changes have been made to the paper, following the
referees recommendations. 16 pages. Published in Classical and Quantum
Gravit
Moving Magnetic Features around a Pore
Spectropolarimetric observations from Sunrise II/IMaX obtained in June 2013
are used for a statistical analysis to determine the physical properties of
moving magnetic features (MMFs) observed near a pore. MMFs of the same and
opposite polarity with respect to the pore are found to stream from its border
at an average speed of 1.3 km s and 1.2 km s respectively, with
mainly same-polarity MMFs found further away from the pore. MMFs of both
polarities are found to harbor rather weak, inclined magnetic fields.
Opposite-polarity MMFs are blue-shifted, while same-polarity MMFs do not show
any preference for up- or downflows. Most of the MMFs are found to be of
sub-arcsecond size and carry a mean flux of 1.2 Mx.Comment: 8 pages, 4 figures, accepted for publication in ApJ
Maximum Entropy Limit of Small-scale Magnetic Field Fluctuations in the Quiet Sun
The observed magnetic field on the solar surface is characterized by a very
complex spatial and temporal behavior. Although feature-tracking algorithms
have allowed us to deepen our understanding of this behavior, subjectivity
plays an important role in the identification and tracking of such features. In
this paper, we continue studies Gorobets, A. Y., Borrero, J. M., & Berdyugina,
S. 2016, ApJL, 825, L18 of the temporal stochasticity of the magnetic field on
the solar surface without relying either on the concept of magnetic features or
on subjective assumptions about their identification and interaction. We
propose a data analysis method to quantify fluctuations of the line-of-sight
magnetic field by means of reducing the temporal field's evolution to the
regular Markov process. We build a representative model of fluctuations
converging to the unique stationary (equilibrium) distribution in the long time
limit with maximum entropy. We obtained different rates of convergence to the
equilibrium at fixed noise cutoff for two sets of data. This indicates a strong
influence of the data spatial resolution and mixing-polarity fluctuations on
the relaxation process. The analysis is applied to observations of magnetic
fields of the relatively quiet areas around an active region carried out during
the second flight of the Sunrise/IMaX and quiet Sun areas at the disk center
from the Helioseismic and Magnetic Imager on board the Solar Dynamics
Observatory satellite.Comment: 11 pages, 5 figures, The Astrophysical Journal Supplement Series
(accepted
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