1,015 research outputs found
Fluxtube model atmospheres and Stokes V zero-crossing wavelengths
First results of the inversion of Stokes I and V profiles from plage regions
near disk center are presented. Both low and high spatial resolution spectra of
FeI 6301.5 and FeI 6302.5 A obtained with the Advanced Stokes Polarimeter (ASP)
have been considered for analysis. The thin flux tube approximation,
implemented in an LTE inversion code based on response functions, is used to
describe unresolved magnetic elements. The code allows the simultaneous and
consistent inference of all atmospheric quantities determining the radiative
transfer with the sole assumption of hydrostatic equilibrium. By considering
velocity gradients within the tubes we are able to match the full ASP Stokes
profiles. The magnetic atmospheres derived from the inversion are characterized
by the absence of significant motions in high layers and strong velocity
gradients in deeper layers. These are essential to reproduce the asymmetries of
the observed profiles. Our scenario predicts a shift of the Stokes V
zero-crossing wavelengths which is indeed present in observations made with the
Fourier Transform Spectrometer.Comment: To appear in ApJ Letters (1997) (in press
Distribución temporal del tamaño de los molariformes de Ursus spelaeus Ros.-Hein.ibérico
[Abstract] This paper deals with a metrical comparison of cheek-teeth length of Ursus spelaeus Ros.-Hein.Iberian population representatives
83 Bronchopulmonary infection/colonization in cystic fibrosis: results from a Spanish multicenter study
A study of the capabilities for inferring atmospheric information from high-spatial-resolution simulations
In this work, we study the accuracy that can be achieved when inferring the
atmospheric information from realistic numerical magneto-hydrodynamic
simulations that reproduce the spatial resolution we will obtain with future
observations made by the 4m class telescopes DKIST and EST. We first study
multiple inversion configurations using the SIR code and the Fe I transitions
at 630 nm until we obtain minor differences between the input and the inferred
atmosphere in a wide range of heights. Also, we examine how the inversion
accuracy depends on the noise level of the Stokes profiles. The results
indicate that when the majority of the inverted pixels come from strongly
magnetised areas, there are almost no restrictions in terms of the noise,
obtaining good results for noise amplitudes up to 1 of . At
the same time, the situation is different for observations where the dominant
magnetic structures are weak, and noise restraints are more demanding.
Moreover, we find that the accuracy of the fits is almost the same as that
obtained without noise when the noise levels are on the order of
1of . We, therefore, advise aiming for noise values on the
order of or lower than 5 of if observers seek reliable
interpretations of the results for the magnetic field vector reliably. We
expect those noise levels to be achievable by next-generation 4m class
telescopes thanks to an optimised polarisation calibration and the large
collecting area of the primary mirror.Comment: 14 pages, 13 figure
Bathyal megabenthic assemblages in the SE Iberian Peninsula (Western Mediterranean Sea)
The Iberian SE is an interesting transition and connectivity zone between the Alboran Sea and the Algerian-Balearic basin. It hosts important deep water fisheries targeting mostly red shrimp (Aristeus antennatus). The area comprises a complex system of tectonic canyons (Mazarron Escarpment), seamounts, knolls and hills (Palos, Planazo, Plis-Plas), and pockmark fields (Acosta et al., 2013). Few studies have been conducted on the bathyal megabenthos, unlike in the neighbouring Chella Bank (De la Torriente et al. 2018) and Balearic Islands (Massuti et al. 2022). The LIFE IP Intemares project is filling this gap
The energy of waves in the photosphere and lower chromosphere: 1. Velocity statistics
Acoustic waves are one of the primary suspects besides magnetic fields for
the chromospheric heating process to temperatures above radiative equilibrium
(RE). We derived the mechanical wave energy as seen in line-core velocities to
obtain a measure of mechanical energy flux with height for a comparison with
the energy requirements in a semi-empirical atmosphere model. We analyzed a
1-hour time series and a large-area map of Ca II H spectra on the traces of
propagating waves. We analyzed the velocity statistics of several spectral
lines in the wing of Ca II H, and the line-core velocity of Ca II H. We
converted the velocity amplitudes into volume and mass energy densities. For
comparison, we used the increase of internal energy necessary to lift a RE
atmosphere to the HSRA temperature stratification. We find that the velocity
amplitude grows in agreement with linear wave theory and thus slower with
height than predicted from energy conservation. The mechanical energy of the
waves above around z~500 km is insufficient to maintain the chromospheric
temperature rise in the semi-empirical HSRA model. The intensity variations of
the Ca line core (z~1000 km) can be traced back to the velocity variations of
the lowermost forming spectral line considered (z~ 250 km). The chromospheric
intensity, and hence, (radiation) temperature variations are seen to be induced
by passing waves originating in the photosphere.Comment: 13 pages, 15 figures + 2 pages Appendix, 5 figures, submitted to A &
Symptom and Quality of Life Improvement in LUX-Lung 8, an Open-Label Phase III Study of Second-Line Afatinib Versus Erlotinib in Patients With Advanced Squamous Cell Carcinoma of the Lung After First-Line Platinum-Based Chemotherapy
INTRODUCTION: In the phase III LUX-Lung 8 trial, afatinib significantly improved progression-free survival (PFS) and overall survival (OS) versus erlotinib in patients with squamous cell carcinoma (SCC) of the lung progressing during or after platinum-based chemotherapy. Patient-reported outcomes (PROs) and health-related quality of life (QoL) in these patients are presented. PATIENTS AND METHODS: Patients (n = 795) were randomized 1:1 to oral afatinib (40 mg/d) or erlotinib (150 mg/d). PROs were collected (baseline, every 28 days until progression, 28 days after discontinuation) using the European Organization for Research and Treatment of Cancer QoL questionnaire and lung cancer-specific module. The percentage of patients improved during therapy, time to deterioration (TTD), and changes over time were analyzed for prespecified lung cancer-related symptoms and global health status (GHS)/QoL. RESULTS: Questionnaire compliance was 77.3% to 99.0% and 68.7% to 99.0% with afatinib and erlotinib, respectively. Significantly more patients who received afatinib versus erlotinib experienced improved scores for GHS/QoL (36% vs. 28%; P = .041) and cough (43% vs. 35%; P = .029). Afatinib significantly delayed TTD in dyspnea (P = .008) versus erlotinib, but not cough (P = .256) or pain (P = .869). Changes in mean scores favored afatinib for cough (P = .0022), dyspnea (P = .0007), pain (P = .0224), GHS/QoL (P = .0320), and all functional scales. Differences in adverse events between afatinib and erlotinib, specifically diarrhea, did not affect GHS/QoL. CONCLUSION: In patients with SCC of the lung, second-line afatinib was associated with improved prespecified disease-related symptoms and GHS/QoL versus erlotinib, complementing PFS and OS benefits with afatinib
Models and Observations of Sunspot Penumbrae
The mysteries of sunspot penumbrae have been under an intense scrutiny for
the past 10 years. During this time, some models have been proposed and
refuted, while the surviving ones had to be modified, adapted and evolved to
explain the ever-increasing array of observational constraints. In this
contribution I will review two of the present models, emphasizing their
contributions to this field, but also pinpointing some of their inadequacies to
explain a number of recent observations at very high spatial resolution. To
help explaining these new observations I propose some modifications to each of
them. These modifications bring those two seemingly opposite models closer
together into a general picture that agrees well with recent 3D
magneto-hydrodynamic simulations.Comment: 9 pages, 1 color figure. Review talk to appear in the proceedings of
the International Workshop of 2008 Solar Total Eclipse: Solar Magnetism,
Corona and Space Weather--Chinese Space Solar Telescope Scienc
LanderPick, a Remote Operated Trawled Vehicle to cost-effectively deploy and recover lightweight oceanographic landers.
Landers are modular structures equipped with miscellaneous sensors and monitoring equipment which are positioned directly on the seabed to operate autonomously for a defined timeframe. A drawback of landers intended to operate for prolonged periods in the deep ocean is the high cost of recovery systems, typically depending on buoyancy modules plus expendable ballast, or requiring ROVs assistance. LanderPick concept consists of the design of a specific trawled vehicle to deploy and recover lightweight oceanographic landers not provided with recovery elements, but having a capture mesh that facilitates their hitching. The LanderPick vehicle is technically a ROTV (Remote Operated Trawled Vehicle) controlled through a standard coaxial electromechanical cable that allows real-time control from the vessel. Navigation is enabled by a low-light high-definition camera, aided by spotlights and laser pointers. Small propellers aid in the final precision approach maneuvers. A mechanical release allows the precise placement at the sea bottom of landers carried as a payload, as well as their recovery by means of a triple hook. First sea missions of the system were carried out successfully in 2021 in southern Biscay. A 4-month deployment of a lander array equipped with current-meters along an energetic canyon axis provided unprecedented detail in the progression of the internal tidal bore. Short (48-hours) deployments of a fully-instrumented lander, including lapse-time image and baits in a deep seamount summit within a marine protected area, provided insights on the biodiversity of a unique ecosystem. The LanderPick novel approach to cost-effectively and precisely deploy and recover lightweight oceanographic landers allows to conceive (i) monitoring systems based on the deployment of arrays or fleets of low-cost landers and (ii) experiments associated with deep habitats such as coral reefs in which it is necessary to locate landers with great precision
LanderPick, a Remote Operated Trawled Vehicle to cost-effectively deploy and recover lightweight oceanographic landers.
Landers are modular structures equipped with miscellaneous sensors and monitoring equipment which are positioned directly on the seabed to operate autonomously for a defined timeframe. A drawback of landers intended to operate for prolonged periods in the deep ocean is the high cost of recovery systems, typically depending on buoyancy modules plus expendable ballast, or requiring ROVs assistance. LanderPick concept consists of the design of a specific trawled vehicle to deploy and recover lightweight oceanographic landers not provided with recovery elements, but having a capture mesh that facilitates their hitching. The LanderPick vehicle is technically a ROTV (Remote Operated Trawled Vehicle) controlled through a standard coaxial electromechanical cable that allows real-time control from the vessel. Navigation is enabled by a low-light high-definition camera, aided by spotlights and laser pointers. Small propellers aid in the final precision approach maneuvers. A mechanical release allows the precise placement at the sea bottom of landers carried as a payload, as well as their recovery by means of a triple hook. First sea missions of the system were carried out successfully in 2021 in southern Biscay. A 4-month deployment of a lander array equipped with current-meters along an energetic canyon axis provided unprecedented detail in the progression of the internal tidal bore. Short (48-hours) deployments of a fully-instrumented lander, including lapse-time image and baits in a deep seamount summit within a marine protected area, provided insights on the biodiversity of a unique ecosystem. The LanderPick novel approach to cost-effectively and precisely deploy and recover lightweight oceanographic landers allows to conceive (i) monitoring systems based on the deployment of arrays or fleets of low-cost landers and (ii) experiments associated with deep habitats such as coral reefs in which it is necessary to locate landers with great precision
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