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Resumen Introduccion La cuantificacion del rango de movimiento de la rodilla es una medida clinicamente relevante en el ambito sanitario, ya que su disminucion puede alterar las actividades de la vida diaria. La obtencion de una medida fiable del rango de movimiento nos permite valorar la eficacia de las intervenciones, asi como la gravedad de la enfermedad. Por esto, el objetivo de este estudio fue conocer la fiabilidad intra e interevaluador de un protocolo para el rango de movimiento articular de la rodilla llevado a cabo con un sensor inercial en sujetos asintomaticos. Metodos Se midio el rango de movimiento de 32 rodillas en sujetos asintomaticos, se realizaron 2 sesiones de medicion, una por evaluador, en el mismo dia. En cada sesion se hicieron un total de 8 mediciones (2 medidas para flexion en decubito supino, 2 medidas para extension en decubito supino, 2 medidas para flexion en bipedestacion y 2 para la extension en bipedestacion). Resultados Para la fiabilidad interevaluador se consiguieron buenos resultados con un ICC superior a 0,79 para todos los movimientos. Los datos obtenidos para la fiabilidad intraevaluador en todos los movimientos fueron excelentes (ICC > 0,88). Conclusion Este estudio obtuvo una excelente fiabilidad interevaluador e intraevaluador para los sujetos sanos midiendo con sensores inerciales.

The solar telescope connected to HARPS-N has been observing the Sun since the summer of 2015. Such high-cadence, long-baseline data set is crucial for understanding spurious radial-velocity signals induced by our Sun and by the instrument. On the instrumental side, this data set allowed us to detect sub-\ms\,systematics that needed to be corrected for. The goal of this manuscript is to i) present a new data reduction software for HARPS-N, ii) demonstrate the improvement brought by this new software on the first three years of the HARPS-N solar data set, and iii) release all the obtained solar products, from extracted spectra to precise radial velocities. To correct for the instrumental systematics observed in the data reduced with the current version of the HARPS-N data reduction software (DRS version 3.7), we adapted the newly available ESPRESSO DRS (version 2.2.3) to HARPS-N and developed new optimized recipes for the spectrograph. We then compared the first three years of HARPS-N solar data reduced with the current and new DRS. The most significant improvement brought by the new DRS is a strong decrease in the day-to-day radial-velocity scatter, from 1.27 to 1.07\ms; this is thanks to a more robust method to derive wavelength solutions, but also to the use of calibrations closer in time. The newly derived solar radial-velocities are also better correlated with the chromospheric activity level of the Sun on the long-term, with a Pearson correlation coefficient of 0.93 compared to 0.77 before, which is expected from our understanding of stellar signals. Finally, we also discuss how HARPS-N spectral ghosts contaminate the measurement of the calcium activity index, and present an efficient technique to derive an index free of instrumental systematics. This paper presents a new data reduction software for HARPS-N, and demonstrates its improvements [...], Comment: 20 pages, 15 figures, 2 tables, version accepted for publication in Astronomy and Astrophysics

Ambrosino, F., et al., Millisecond spinning, low-magnetic-field neutron stars are believed to attain their fast rotation in a 0.1–1-Gyr-long phase during which they accrete matter endowed with angular momentum from a low-mass companion star. Despite extensive searches, coherent periodicities originating from accreting neutron star magnetospheres have been detected only at X-ray energies and in ~10% of the currently known systems. Here we report the detection of optical and ultraviolet coherent pulsations at the X-ray period of the transient low-mass X-ray binary system SAX J1808.4−3658, during an accretion outburst that occurred in August 2019. At the time of the observations, the pulsar was surrounded by an accretion disk, displayed X-ray pulsations and its luminosity was consistent with magnetically funnelled accretion onto the neutron star. Current accretion models fail to account for the luminosity of both optical and ultraviolet pulsations; these are instead more likely to be driven by synchro-curvature radiation in the pulsar magnetosphere or just outside of it. This interpretation would imply that particle acceleration can take place even when mass accretion is going on, and opens up new perspectives in the study of coherent optical/ultraviolet pulsations from fast-spinning accreting neutron stars in low-mass X-ray binary systems., A.M.Z. thanks the HST contact scientist, D. Welty (STScI), for constant support in the observation planning and T. Royle (STScI) for checking the scheduling processes. A.M.Z. thanks A. Riley (STIS Team) for the support in the scientific data analysis. A.M.Z. acknowledges the support of the PHAROS COST Action (CA16214) and A. Ridolfi for his help in data analysis. A.M.Z. would also like to thank G. Benevento for comments on draft. F.C.Z. is supported by a Juan de la Cierva fellowship. S.C. and P.D.A. acknowledge support from ASI grant I/004/11/3. D.d.M., A.P. and L.S. acknowledge financial support from the Italian Space Agency (ASI) and National Institute for Astrophysics (INAF) under agreements ASI-INAF I/037/12/0. L.B., D.d.M., T.D.S., A.P. and L.S. acknowledge financial contributions from ASI-INAF agreement no. 2017-14-H.0, INAF main-stream (principal investigator: T. Belloni; principal investigator: A. De Rosa). D.F.T. acknowledges support from grants PGC2018-095512-B-I00, SGR2017-1383 and AYA2017-92402-EXP. L.B and T.D.S. thank A. Marino for useful discussions and acknowledge financial contributions from the HERMES project financed by the Italian Space Agency (ASI) agreement no. 2016/13 U.O. T.D.S. and L.S. acknowledge the iPeska research grant (principal investigator: A. Possenti) funded under the INAF national call Prin-SKA/CTA approved with the Presidential Decree 70/2016. A.P., F.C.Z., and D.T. acknowledge the International Space Science Institute (ISSI-Beijing), which funded and hosted the international team ‘Understanding and Unifying the Gamma-rays Emitting Scenarios in High Mass and Low Mass X-ray Binaries’.

LOCNES (LOw-Cost NIR Extended Solar telescope) is a solar telescope installed at the TNG (Telescopio Nazionale Galileo). It feeds the light of the Sun into the NIR spectrograph GIANO-B through a 40-m patch of optical fibers. LOCNES has been designed to obtain high signal-to-noise ratio spectra of the Sun as a star with an accurate wavelength calibration through molecular-band cells. This is an entirely new area of investigation that will provide timely results to improve the search of telluric planets with NIR spectrographs such as iSHELL, CARMENES, and GIANO-B. We will extract several disc-integrated activity indicators and average magnetic field measurements for the Sun in the NIR. Eventually, they will be correlated with both the RV of the Sun-as-a -star and the resolved images of the solar disc in visible and NIR. Such an approach will allow for a better understanding of the origin of activity-induced RV variations in the two spectral domains and will help in improving the techniques for their corrections. In this paper, we outline the science drivers for the LOCNES project and its first commissioning results.

During the last few years we have been working on a modernization plan for the Telescopio Nazionale Galileo (TNG) Control System1,2. On October 2019 we had the opportunity to execute the first step of this process. The telescope was going to be stopped for one month due to M1 mirror being aluminized, so we could change the azimuth control system, that had been thoroughly tested during the summer, with no additional observational time loss. In this paper we present the new control system based on the CompactRIO platform from National Instruments, the switching process between the old and the new control systems, and a performance comparison between them.

Stellar magnetic activity produces time-varying distortions in the photospheric line profiles of solar-type stars. These lead to systematic errors in high-precision radial-velocity measurements, which limit efforts to discover and measure the masses of low-mass exoplanets with orbital periods of more than a few tens of days. We present a new data-driven method for separating Doppler shifts of dynamical origin from apparent velocity variations arising from variability-induced changes in the stellar spectrum. We show that the autocorrelation function (ACF) of the cross-correlation function used to measure radial velocities is effectively invariant to translation. By projecting the radial velocities on to a subspace labelled by the observation identifiers and spanned by the amplitude coefficients of the ACF's principal components, we can isolate and subtract velocity perturbations caused by stellar magnetic activity. We test the method on a 5-year time sequence of 853 daily 15-minute observations of the solar spectrum from the HARPS-N instrument and solar-telescope feed on the 3.58-m Telescopio Nazionale Galileo. After removal of the activity signals, the heliocentric solar velocity residuals are found to be Gaussian and nearly uncorrelated. We inject synthetic low-mass planet signals with amplitude $K=40$ cm s$^{-1}$ into the solar observations at a wide range of orbital periods. Projection into the orthogonal complement of the ACF subspace isolates these signals effectively from solar activity signals. Their semi-amplitudes are recovered with a precision of $\sim~6.6$ cm s$^{-1}$, opening the door to Doppler detection and characterization of terrestrial-mass planets around well-observed, bright main-sequence stars across a wide range of orbital periods., 19 pages, 15 figures, accepted 2 May 2021 for publication in MNRAS

Context. The existence of hot Jupiters is still not well understood. Two main channels are thought to be responsible for their current location: a smooth planet migration through the protoplanetary disk or the circularization of an initial highly eccentric orbit by tidal dissipation leading to a strong decrease in the semimajor axis. Different formation scenarios result in different observable effects, such as orbital parameters (obliquity and eccentricity) or frequency of planets at different stellar ages. Aims. In the context of the GAPS Young Objects project, we are carrying out a radial velocity survey with the aim of searching and characterizing young hot-Jupiter planets. Our purpose is to put constraints on evolutionary models and establish statistical properties, such as the frequency of these planets from a homogeneous sample. Methods. Since young stars are in general magnetically very active, we performed multi-band (visible and near-infrared) spectroscopy with simultaneous GIANO-B + HARPS-N (GIARPS) observing mode at TNG. This helps in dealing with stellar activity and distinguishing the nature of radial velocity variations: stellar activity will introduce a wavelength-dependent radial velocity amplitude, whereas a Keplerian signal is achromatic. As a pilot study, we present here the cases of two known hot Jupiters orbiting young stars: HD 285507 b and AD Leo b. Results. Our analysis of simultaneous high-precision GIARPS spectroscopic data confirms the Keplerian nature of the variation in the HD 285507 radial velocities and refines the orbital parameters of the hot Jupiter, obtaining an eccentricity consistent with a circular orbit. Instead, our analysis does not confirm the signal previously attributed to a planet orbiting AD Leo. This demonstrates the power of the multi-band spectroscopic technique when observing active stars., With funding from the Spanish government through the "María de Maeztu Unit of Excellence" accreditation (MDM-2017-0737)

The design of the next generation of β-stabilized γ-TiAl based alloys as structural materials for high-temperature applications in aircraft engines requires the precise knowledge of the mobility of defects in the ordered β o phase. To reach this goal a Mo-rich prototype alloy has been specifically produced and investigated. The mobility of defects, between 600 K and 1635 K, has been studied by mechanical spectroscopy. The internal friction spectra show a relaxation peak P1 (at 1130 K for 1 Hz) superimposed to a high-temperature background. We demonstrate that the relaxation peak is taking place inside the β o phase and measure an activation energy of E P1 = 3.55 ± 0.05 eV. An atomistic model is additionally proposed to explain this relaxation peak, which is attributed to a Zener-like mechanism of stress-induced Mo-Mo dipoles reorientation by exchange with a vacancy, and consequently the measured activation energy corresponds to the one for Mo diffusion in the β o phase.

Advanced intermetallic γ-TiAl based alloys, which solidify via the disordered β phase, such as the TNM+ alloy, are considered as most promising candidates for structural applications at high temperatures in aero and automotive industries, where they are applied increasingly. Particularly creep resistant microstructures required for high-temperature application, i.e. fine fully lamellar microstructures, can be attained via two-step heat-treatments. Thereby, an increasing creep resistance is observed with decreasing lamellar interface spacing. Once lamellar structures reach nano-scaled dimensions, deformation mechanisms are altered dramatically. Hence, this study deals with a detailed characterization of the elevated temperature deformation phenomena prevailing in nano-lamellar TiAl alloys by the use of tensile creep experiments and mechanical spectroscopy. Upon creep exposure, microstructural changes occur in the lamellar structure, which are analyzed by the comparative utilization of X-ray diffraction, scanning and transmission electron microscopy as well as atom probe tomography. Creep activation parameters determined by mechanical characterization suggest the dominance of dislocation climb by a jog-pair formation process. The dislocations involved in deformation are, in nano-lamellar TiAl alloys, situated at the lamellar interfaces. During creep exposure the precipitation of βo phase and ζ-silicide particles is observed emanating from the α2 phase, which is due to the accumulation of Mo and Si at lamellar interfaces.

Severe plastic deformation (SPD) frequently induces phase transformations like decomposition of supersaturated solid solution, dissolution of precipitates, amorphization, nanocrystallization etc. Such diffusive phase transitions are combined with SPD-driven accelerated mass transfer. Displacive (or martensitic) phase transitions can also take place and in combination with diffusive ones have not been investigated in depth in severely deformed materials. The goal of this work is to investigate the combination of displacive (austenite↔martensite) and diffusive (decomposition of supersaturated solid solution) phase transitions in two different Cu–Al–Ni shape memory alloys under the influence of high-pressure torsion (HPT). After homogenization in the one-phase (austenitic) β-area of Cu–Al–Ni phase diagram and quenching, the first alloy was in martensitic state (mainly β′3 martensite with a small amount of γ′3 martensite), and the second one remained austenitic (β3 phase). The HPT of these alloys led to the precipitation of α1-phase in the first case and γ1-phase in the second one (as if they were annealed at an effective temperature Teff = 620 ± 20 °C). As a result of precipitation, the matrix in the first alloy was enriched and in the second one depleted in Al. After HPT, both alloys contained mainly β′3 martensite with a certain amount of γ′3 martensite. Thus, the HPT-driven diffusive transformations (precipitation of α1-and γ1-phase) influence the followed displacive (martensitic) transformation. Simultaneously, a dramatic grain refinement is obtained and the reported results open new possibilities to investigate the superelastic and shape memory effects in nanostructured Cu–Al–Ni alloys.

Supplemental Digital Content is available in the text., Objectives: To compare the outcomes of sepsis management using protocol-based therapy versus non-protocolized care, assessed over 10 years. Design: Retrospective cohort study, analyzed longitudinally with risk-adjusted control charts, referenced against hospital- and unit-level programs or interventions. Setting: Private, tertiary teaching hospital ICU in the Philippines. Patients: Nine-hundred fifty adult patients (19 yr old or older) diagnosed with severe sepsis or septic shock, using 2001 consensus definitions, admitted to the ICU from September 2007 to August 2017. Interventions: Three iterations of a standard clinical pathway (including early antibiotics, prescribed fluid resuscitation, and hemodynamic management) versus concurrent non-protocolized care. Measurements and Main Results: Seven-hundred sixty patients were in the protocol-based care group versus 190 in the non-protocolized care group. Protocol-based management was associated with lower hospital mortality (28.4% vs 44.7%; p = 0.00) and ICU mortality (24.2% vs 31.6%; p = 0.038). There were no differences in ICU or hospital length-of-stay, mechanical ventilator days, or vasoactive days. Risk-Adjusted Cumulative Sum and Risk-Adjusted Exponentially Weighted Moving Average control charts showed that a survival advantage was achieved after 1 year and was sustained over the duration of the study. Conclusions: Protocol-based management was associated with sustained improvements in the survival of sepsis patients over 10 years in this hospital setting, after a run-in period of 1 year. Hospital- and unit-level interventions may have measurable impacts on the efficacy of sepsis clinical pathways.

(Abridged) We perform a detailed study of the main optical activity indicators (Ca II H & K, Balmer lines, Na I D$_{\rm 1}$ D$_{\rm 2}$, and He I D$_{\rm 3}$) measured for the Sun using the data provided by the HARPS-N solar-telescope feed at the Telescopio Nazionale Galileo. The value of the solar rotation period is found in all the activity indicators, with the only exception being H$\delta$. The derived values vary from 26.29 days (H$\gamma$ line) to 31.23 days (He I). From an analysis of sliding periodograms we find that in most of the activity indicators the spectral power is split into several "bands" of periods around 26 and 30 days, that might be explained by the migration of active regions between the equator and a latitude of $\sim$ 30$^{\circ}$, spot evolution or a combination of both effects. In agreement with previous works a typical lifetime of active regions of $\sim$ ten rotation periods is inferred from the pooled variance diagrams. We find that H$\alpha$, H$\beta$, H$\gamma$, H$\epsilon$, and He I show a significant correlation with the S index. Significant correlations between the contrast, bisector span, and the heliocentric radial velocity with the activity indexes are also found. We show that the full width at half maximum, the bisector, and the disc-integrated magnetic field correlate with the radial velocity variations. The correlation of the S index and H$\alpha$ changes with time, increasing with larger sun spot numbers and solar irradiance. A similar tendency with the S index - radial velocity correlation is also present in the data. Our results are consistent with a scenario in which higher activity favours the correlation between the S index and the H$\alpha$ activity indicators and between the S index and radial velocity variations., Comment: Accepted by Astronomy & Astrophysics

Cu-Al-based shape memory alloys are firm candidates to be used up to 473 K. The main limiting aspect is the activation of diffusion processes in the metastable austenite phase, which drive the alloy decomposition. In the present work the study of short-distance diffusion processes has been approached by internal friction. A relaxation peak has been found in the metastable beta (D0(3)) phase of a Cu-Al-Be shape memory alloy, around 500 K (at 1 Hz), with an activation energy of E-a = 138 +/- 0.05 eV. An atomic mechanism of elastic dipoles Antisite-Vacancy reorientation, involving stress-assisted short distance Cu-atoms diffusion, has been proposed. (C) 2016 Elsevier B.V. This work was supported by the European H2020 Project REACT, Grant No 640241, and the Spanish Ministry MINECO projects, MAT2012-36421 and CONSOLIDER-INGENIO 2010 CSD2009-00013, as well as by the Consolidated Research Group IT-1090-16 from the Education Department and the project ELKARTEK ACTIMAT, KK-2015/0000094, from the Industry Department of the Basque Government.

In the present work we have studied the high-temperature shape memory alloys based on the Ru-Nb system by using two mechanical spectrometers working in temperature ranges from 200 to 1450ºC and -150 to 900ºC. We have studied internal friction peaks linked to the martensitic transformations in the range from 300 to 1200ºC. In addition, we have evidenced another internal friction peak at lower temperature than the transformations peaks, which apparently exhibits the behaviour of a thermally activated relaxation peak, but in fact is a strongly time-dependent peak. We have carefully studied this peak and discussed its microscopic origin, concluding that it is related to the interaction of some structural defects with martensite interfaces. Finally, we perform a complete analysis of the whole internal friction spectrum, taking into account the possible relationship between the time-dependent peak and the martensitic transformation behaviour.

International audience; In many Ni-based superalloys, dynamic strain aging (DSA) generates an inhomogeneous plastic deformation resulting in jerky flow known as the Portevin--Le Chatelier (PLC) effect. This phenomenon has a deleterious effect on the mechanical properties and, at high temperature, is related to the diffusion of substitutional solute atoms toward the core of dislocations. However, the question about the nature of the atomic species responsible for the PLC effect at high temperature still remains open. The goal of the present work is to answer this important question; to this purpose, three different 718-type and a 625 superalloy were studied through a nonconventional approach by mechanical spectroscopy. The internal friction (IF) spectra of all the studied alloys show a relaxation peak P718 (at 885 K for 0.1 Hz) in the same temperature range, 700 K to 950 K, as the observed PLC effect. The activation parameters of this relaxation peak have been measured, Ea(P718){\thinspace}={\thinspace}2.68{\thinspace}{\textpm}{\thinspace}0.05 eV, $\tau$0{\thinspace}={\thinspace}2{\textperiodcentered}10-15 {\textpm} 1 s as well as its broadening factor $\beta${\thinspace}={\thinspace}1.1. Experiments on different alloys and the dependence of the relaxation strength on the amount of Mo attribute this relaxation to the stress-induced reorientation of Mo-Mo dipoles due to the short distance diffusion of one Mo atom by exchange with a vacancy. Then, it is concluded that Mo is the atomic species responsible for the high-temperature PLC effect in 718 superalloy

Context. Stellar activity is currently challenging the detection of young planets via the radial velocity (RV) technique. Aims. We attempt to definitively discriminate the nature of the RV variations for the young active K5 star BD+20 1790, for which visible (VIS) RV measurements show divergent results on the existence of a substellar companion. Methods. We compare VIS data with high precision RVs in the near infrared (NIR) range by using the GIANO - B and IGRINS spectrographs. In addition, we present for the first time simultaneous VIS-NIR observations obtained with GIARPS (GIANO - B and HARPS - N) at Telescopio Nazionale Galileo (TNG). Orbital RVs are achromatic, so the RV amplitude does not change at different wavelengths, while stellar activity induces wavelength-dependent RV variations, which are significantly reduced in the NIR range with respect to the VIS. Results. The NIR radial velocity measurements from GIANO - B and IGRINS show an average amplitude of about one quarter with respect to previously published VIS data, as expected when the RV jitter is due to stellar activity. Coeval multi-band photometry surprisingly shows larger amplitudes in the NIR range, explainable with a mixture of cool and hot spots in the same active region. Conclusions. In this work, the claimed massive planet around BD+20 1790 is ruled out by our data. We exploited the crucial role of multi- wavelength spectroscopy when observing young active stars: thanks to facilities like GIARPS that provide simultaneous observations, this method can reach its maximum potential., 12 pages, 7 figures

GIARPS (GIAno and haRPS) is a project devoted to have on the same focal station of the Telescopio Nazionale Galileo (TNG) both high resolution spectrographs, HARPS-N (VIS) and GIANO-B (NIR), working simultaneously. This could be considered the first and unique worldwide instrument providing cross-dispersed echelle spectroscopy at a resolution of 50,000 in the NIR range and 115,000 in the VIS and over in a wide spectral range (0.383-2.45 μm) in a single exposure. The science case is very broad, given the versatility of such an instrument and its large wavelength range. A number of outstanding science cases encompassing mainly extra-solar planet science starting from rocky planets search and hot Jupiters to atmosphere characterization can be considered. Furthermore both instruments can measure high precision radial velocities by means the simultaneous thorium technique (HARPS-N) and absorbing cell technique (GIANO-B) in a single exposure. Other science cases are also possible. GIARPS, as a brand new observing mode of the TNG started after the moving of GIANO-A (fiber fed spectrograph) from Nasmyth-A to Nasmyth-B where it was re-born as GIANO-B (no more fiber feed spectrograph). The official Commissioning finished on March 2017 and then it was offered to the community. Despite the work is not finished yet. In this paper we describe the preliminary scientific results obtained with GIANO-B and GIARPS observing mode with data taken during commissioning and first open time observations.

The quality of SiFAP (Silicon Fast Astronomical Photometer) at the TNG has already shown its ability to easily detect optical pulses from transitional millisecond pulsars and from other slower neutron stars. Up to now the photometer based on Silicon Photo Multipliers manufactured by Hamamatsu Photonics (MPPC, Multi Pixel Photon Counter) was mounted (on and manually aligned with) a MOS mask at the F/11 focal plane of the telescope. In order to have a more versatile instrument with the possibility to remotely center and point several targets during the night we have decided to build a new mechanical support for the MPPCs and mount it on the Namsyth Interface (NI), where originally OIG and later GIANO were hosted. The MPPC module devoted to observe the target will be placed at the center of the FoV (on-axis), while the reference signal will be collected from a peripheral star in the FoV (Field of view) by means of the MPPC module that will be set at this position by a combination of a linear stage movement and a derotator angle. At the same time we have introduced the option for a polarimetric mode, with a 3rd MPPC module and a polarizing cube beam-splitter that separates the states between this and the on axis MPPC. SiFAP has been developed with 3 independent custom electronic chains for data acquisition, exploiting the 3 different outputs (analog, digital, USB pre-processed) provided by the MPPCs modules. The electronic chain fed by the analog output is able to tag a single photon ToA (Time of Arrival) with a time resolution of 25 ns, while the remaining electronic chains can integrate the signal into time bins from 100 ms down to 20 μs. The absolute time is provided by a GPS unit with a time resolution of 25 ns at 50% of the rising edge of the 1PPS (1 Pulse Per Second) signal which is linked to the UTC (Universal Time Coordinated). Apart from the versatility with the remotely controlled on sky configuration of the MPPCs, the mounting of SiFAP2 at the NI allows for a permanent hosting of the instrument, readily available for observations. The new polarimetric mode will then offer other scientific opportunities that have not been explored so far in high-temporal resolution astronomy.

In the present work we have studied a high temperature Ru-50Nb (at.%) shape memory alloy using a mechanical spectrometer able to work in the temperature range from 473 to 1723 K. We have investigated two internal friction peaks, as well as the dynamic modulus variation, linked to the martensitic transformations in the range from 573 K to 1473 K. In addition, we have evidenced another internal friction peak P LT at lower temperature than the transformation peaks, which apparently exhibits the behaviour of a thermally activated relaxation peak. However, we show that this peak is not a relaxation one because it exhibits a strongly time-dependent behaviour. We have carefully analysed this peak and discussed its microscopic origin, concluding that it is related to the interaction of some structural defects with martensite interfaces.

High-pressure torsion has been successfully applied to polycrystalline Cu–Al–Ni shape memory alloys that had been prepared by a powder metallurgy methodology. The samples before and after high-pressure torsion were characterized by optical and electron microscopy and differential scanning calorimetry. After high-pressure torsion the alloys became ultra-fine grained and the present phases were identified.

A 4x4 array of square cross-section micro-pillars was milled by focused ion beam technique on an [001] Cu-Al-Ni shape memory alloy single crystal. All pillars in the array were tested in nano-compression using an instrumented nanoindenter. The micro-pillars superelastic response was tested over hundreds cycles on all pillars and over thousands on two randomly selected pillars. Superelastic behavior was evaluated from its load-depth curves individually using the loss factor as evaluation parameter in the 200th cycle. Recoverable and reproducible superelastic behavior has been observed during the long-term cycling tests and the mean loss factor was 0.16. These results open the door for the design of devices that could be integrated in MEMS technology with a good reliability.

A novel shape memory alloy (SMA) has been developed as an alternative to currently available alloys. This alloy, commercially known by its proprietary brand SMARQ, shows a higher working range of temperatures with respect to the SMA materials used until now in actuators, limited to environment temperatures below 90 °C. SMARQ is a high temperature SMA (HTSMA) based on a fully European material technology and production processes, which allows the manufacture of high quality products, with tuneable transformation temperatures up to 200 °C. Both, material and production processes have been evaluated for its use in space applications. A full characterization test campaign has been completed in order to obtain the material properties and check its suitability to be used as active material in space actuators. In order to perform the functional characterization of the material, it has been considered as the key element of a basic SMA actuator, consisting in the SMA wire and the mechanical and electrical interfaces. The functional tests presented in this work have been focused on the actuator behavior when heated by means of an electrical current. Alloy composition has been adjusted in order to match a transition temperature (As) of +145 °C, which satisfies the application requirements of operating temperatures in the range of −70 and +125 °C. Details of the tests and results of the characterization test campaign, focused in the material unique properties for their use in actuators, will be presented in this work. Some application examples in the field of space mechanisms and actuators, currently under development, will be summarized as part of this work, demonstrating the technology suitability as active material for space actuators.

An advanced intermetallic γ-TiAl-based alloy containing Nb and Mo has been studied to understand the microscopic mechanisms taking place during thermal treatments carried out to adjust a fine, nearly lamellar microstructure. The evolution of the microstructure has been characterized by high-energy X-ray diffraction and electron microscopy, while the atomistic mechanisms of defect mobility have been studied through internal friction and dynamic modulus measurements. An internal friction relaxation peak has been observed at about 1050 K (for 1 Hz) in the initial oversaturated α2-Ti3Al phase, whose intensity strongly decreases after precipitation of the γ-TiAl laths. The activation parameters of this relaxation have been measured, Hact = 3.1 ± 0.05 eV, τ0 = 8.3 × 10−17 s and β = 1.3, and the relaxation is attributed to a point defect mechanism taking place inside the supersaturated α2-Ti3Al phase. A new Zener-like atomistic model based on stress-induced reorientation of Al–VTi–Al dipoles has been developed to explain the observed relaxation, resolving the controversy concerning the relaxation peak at 1050 K present in many γ-TiAl-based alloys. Precipitation of the γ-lamellae has also been considered as being responsible for the dynamic modulus hardening and, additionally, for another contribution to the internal friction at higher temperature than the described relaxation. Finally, the theoretical Debye equations as a function of temperature, for both internal friction and dynamic modulus, have been applied, using the measured activation parameters, to perform a deconvolution of the relaxation and precipitation contributions. The obtained results agree well with the experimental ones at different frequencies, allowing a global interpretation of the involved atomic processes.

In situ neutron diffraction is used to study the strain relaxation on a single crystal and other powdered Cu-Al-Ni shape memory alloys (SMAs) around martensitic transformation temperatures. This work is focused on the analysis of the strain evolution along the temperature memory effect appearing in these alloys after partial thermal transformations. A careful study of the influence of partial cycling on the neutron diffraction spectra in the martensitic phase is presented. Two different effects are observed, the d-spacing position shift and the narrowing of various diffraction peaks, along uncompleted transformation cycles during the thermal reverse martensitic transformation. These changes are associated with the relaxation of the mechanical stresses elastically stored around the martensitic variants, due to the different self-accommodating conditions after uncompleted transformations. The evolution of the stresses is measured through the strain relaxation, which is accessible by neutron diffraction. The observed effects and the measured strain relaxations are in agreement with the predictions of the model proposed to explain this behavior in previous calorimetric studies. In addition, the thermal expansion coefficients of both martensite and austenite phases were measured. The neutron experiments have allowed a complete description of the strains during martensitic transformation, and the obtained conclusions can be extrapolated to other SMA systems.In situ neutron diffraction is used to study the strain relaxation on a single crystal and other powdered Cu-Al-Ni shape memory alloys (SMAs) around martensitic transformation temperatures. This work is focused on the analysis of the strain evolution along the temperature memory effect appearing in these alloys after partial thermal transformations. A careful study of the influence of partial cycling on the neutron diffraction spectra in the martensitic phase is presented. Two different effects are observed, the d-spacing position shift and the narrowing of various diffraction peaks, along uncompleted transformation cycles during the thermal reverse martensitic transformation. These changes are associated with the relaxation of the mechanical stresses elastically stored around the martensitic variants, due to the different self-accommodating conditions after uncompleted transformations. The evolution of the stresses is measured through the strain relaxation, which is accessible by neutron diffraction. The...

In this work we overview the extrinsic size-effects on the martensitic transformation reported in the literature by nano compression tests in micro and sub-micrometer pillars, as well as by in situ superelastic tests at the transmission electron microscope. Three different size-effects are described: The increase of the critical stress for superelasticity at nano scale, the decrease of the stress for recovery during the reverse stress-induced martensitic transformation at micro and nano scale and finally the change of the selection rule for the martensitic variants promoted at micro and nano scale. New results are presented to illustrate the behavior of these size-effects and the microscopic origin of such effects is discussed. A consistent interpretation is given and explained for each one of the reported size-effects on the martensitic transformation.

Among the different Cu-based shape memory alloys, the Cu–Al–Be family exhibits a particular technological interest for intermediate and low temperature applications. In this work we studied the martensitic transformation behavior of Cu–Al–Be single crystalline shape memory alloys with three different concentrations. The influence of four specific thermal treatments of quenching and aging on the transformation temperatures has been studied by differential scanning calorimetry and compared with similar studies by mechanical spectroscopy. The analysis of the influence of thermal treatments on the martensitic transformation behavior allows optimize a treatment useful for all the alloys transforming between 200 K and 400 K, avoiding both stabilization and precipitation. In addition, an anomalous jerky behavior has been reported for the alloy with low transformation temperatures, which is discussed in terms of the possible mechanisms.

Among active materials, shape memory alloys are well recognized for their work output density. Because of that, these alloys have attracted much attention to be used in micro/nano electromechanical systems. In the present work, the electron beam evaporation technique has been used to growth, by a multilayer method, two shape memory alloy thin films with different Cu–Al–Ni composition. Multilayers have been further thermally treated to produce the alloys by solid solution diffusion. The produced multilayers have been characterized and the presence of the martensite phase in the obtained thin films was studied. Furthermore, the influence of two different coatings onto the Si substrates, namely Si/SiO 2 and Si/Si 3 N 4 , was investigated. Mechanically stable, not detaching from the substrates, Cu–Al–Ni shape memory alloy thin films, about 1 micrometre thick, showing a martensitic transformation have been produced.

Objective To develop a score to predict mortality in patients with bloodstream infections (BSIs) due to carbapenemase-producing Enterobacteriaceae (CPE). Patients and Methods A multinational retrospective cohort study (INCREMENT project) was performed from January 1, 2004, through December 31, 2013. Patients with clinically relevant monomicrobial BSIs due to CPE were included and randomly assigned to either a derivation cohort (DC) or a validation cohort (VC). The variables were assessed on the day the susceptibility results were available, and the predictive score was developed using hierarchical logistic regression. The main outcome variable was 14-day all-cause mortality. The predictive ability of the model and scores were measured by calculating the area under the receiver operating characteristic curve. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were calculated for different cutoffs of the score. Results The DC and VC included 314 and 154 patients, respectively. The final logistic regression model of the DC included the following variables: severe sepsis or shock at presentation (5 points); Pitt score of 6 or more (4 points); Charlson comorbidity index of 2 or more (3 points); source of BSI other than urinary or biliary tract (3 points); inappropriate empirical therapy and inappropriate early targeted therapy (2 points). The score exhibited an area under the receiver operating characteristic curve of 0.80 (95% CI, 0.74-0.85) in the DC and 0.80 (95% CI, 0.73-0.88) in the VC. The results for 30-day all-cause mortality were similar. Conclusion A validated score predictive of early mortality in patients with BSIs due to CPE was developed. Trial Registration clinicaltrials.gov Identifier: NCT01 764490. © 2016 Mayo Foundation for Medical Education and Research

Weevils are members of the beetle family, Curculionidae, which comprises approximately 4,600 genera and 51,000 species (Oberprieler et al. 2007). In Mexico, more than 2,300 species have been reported and 6.5% and 40.5% of the genera and species, respectively, are endemic (Anderson & O'Brien 1996). Most weevils are phytophagous during both larval and adult stages (Marvaldi & Lanteri 2005). The genus Rhyssomatus includes more than 150 Neotropical and Nearctic species, many of which are of agricultural importance (Viale 1951; Viale & Thomas 1954; Santos et al. 2001). In Costa Rica, the presence of a Rhyssomatus, nr. R. subcostatus Fahraeus, was observed attacking yam (Ipomoea spp.; Solanales: Convalvulaceae) crops, while in Argentina R. subtilis Fiedler was recently reported attacking soybean (Glycine max (L.) Merr.; Fabales: Fabaceae) (Viale 1951; Viale & Thomas 1954; Socfas et al. 2009). In Mexico, 27 species of Rhyssomatus have been reported (Kissinger 1962; O'Brien & Wibmer, 1982; Maes & O'Brien 1990; Salas-Araiza et al. 2001; Mor rone et al. 2002); but none has been considered as an agricultural pest. Soybean is widely planted in Mexico, and in 2011 the surface area dedicated to the soybean crop was 167,925 ha, with a production of 183, 9811, mainly in the states of Tamaulipas, San Lu is Potosi, Chiapas, Veracruz and Campeche (SIAP 2012). However, no information is available of Rhyssomatus on soybean. Therefore, this paper reports for the first time, R. nigerrimus attacking soybean crops in northern and southern Mexico. It also presents notes on its field bioecology. For the last 3 yr through pest monitoring in soybean crops in the municipality of Altamira, Tamaulipas, Mexico, in the "Brecha de Corpus" zone and in El Manzano, Tapachula, Chiapas, the presence of a black weevil that attacks soybean in both vegetative and reproductive stages has been detected. In the 2009 spring-summer crop in southern Tamaulipas, the weevil was observed to cause considerable damage to pods on approxi mately 1800 ha of soybean. Considerable damage caused by this weevil has also been detected on approximately 3,000 ha of soybean crops in Tapa chula, Chiapas. In both places the weevils dam aged up to 48% of the pods, and the damage was distributed uniformly throughout the soybean crop. Recently, in 2011, the weevil was found in volunteer soybean plants in areas where soybean had been cultivated in the municipality of Ebano, San Luis Potosi.

Superelastic nanocompression tests are performed on different micropillars milled by focused ion beam from [0 0 1]-oriented single crystals of Cu–Al–Ni shape memory alloys. Over hundreds of cycles such micropillars exhibit reproducible superelastic behavior with complete recovery at stresses around 300 MPa and stress-induced transformation strains above 5%. Upon cycling, the critical stress to induce the transformation decreases, and the transformation strain increases, both signatures of a training effect which is analyzed here in terms of the microscopic mechanisms controlling the nucleation, growth and recovery of the martensite plates. The mechanical hysteresis is characterized through the energy dissipated during closed superelastic cycles, and its evolution during cycling is discussed. The superelastic cycling of the micropillars is also found to depend on the strain rate. The highest strain rate studied here, 10−1 s−1, is found to impinge upon the nucleation and growth kinetics of γ 3 ′ and β 3 ′ martensites, with the result that the mechanical hysteresis and transformation strain are reduced. Finally, specific cycling tests have been conducted at increasing maximum loads to analyze the limit for plastic deformation of the micropillar, which happens between 500 and 700 MPa.

The temperature memory effects (TME) in shape memory alloys (SMA), which appear after incomplete reverse martensitic transformations, strongly modify the kinetics of successive heating runs. In the present work, these TME have been studied in Cu–Al–Ni alloys by adiabatic calorimetry and optical microscopy. The influence of the different martensitic crystallographic structures, the size of the martensite variants, the physical state of the sample, as well as the number of previous partial cycles are discussed. New results in powdered samples are compared with those obtained in single crystals. The analysis of the experimental data within the frame of a simple thermodynamic model suggests the presence of a high number of martensite plates, which permits a continuous distribution of the elastic energy throughout the crystal, as a necessary condition for these thermal effects. Their knowledge is of paramount importance to improve the reliability of SMA devices.

Stress-induced martensite nucleation and further growing, in Cu–Al–Ni shape memory alloys, have been studied during in situ superelastic tests in the transmission electron microscope. Two kinds of martensite, β 3 ′ and γ 3 ′ , are induced and can coexist under stress, both exhibiting in a high density of stacking faults. The interface plane and the orientation relationships between the different variants of such martensites have been determined, and the atomic configurations of the lattices across the interface have been described. Finally, in light of the results, selection rules for the stress-induced promoted martensites at the nano-scale have been established, being determined by the shear direction and the basal plane of the martensite lattice.

The study of anelastic relaxation by means of mechanical spectroscopy gives a unique insight into the mechanisms of defect mobility, and provides crucial information for the development of new intermetallic materials. In this work, a new high-temperature mechanical spectrometer, working up to 1800 K, is used to perform such study in order to better understand the underlying processes controlling plasticity in an advanced Fe-38% Al intermetallic. The measured internal friction spectra, as a function of temperature for different frequencies, show one internal friction peak at about 1100 K with a background increasing exponentially with temperature up to 1350 K. In this work we apply a model that gives a consistent description of the high-temperature internal friction background in order to obtain the parameters characterizing the involved relaxation processes: Hact = 5.4 ± 0.2 eV and τ0 = 1.4 × 10−19 s. This apparent activation energy of the high-temperature background is compared with results in the literature obtained by creep tests and discussed in terms of the possible microscopic mechanisms. Moreover, the subtraction of the obtained background allowed a more precise measure of the activation enthalpy for the 1100 K relaxation peak: Hpeak = 2.98 ± 0.02 eV. We conclude that the mechanisms operating in this temperature range should be related to those controlling creep in these materials.

The phase transformation and nanoindentation response as a function of crystallinity of NiTi thin films were assessed. A phase change was detectable in samples with 1% crystallization. Measured mechanical properties indicate that the films soften with crystallization. Films partway through crystallization presented a bimodal response: crystalline regions had moduli similar to fully crystallized films; and amorphous regions had larger moduli (larger than as-deposited amorphous films) attributable to structural relaxation. A modified Voigt model describes the evolution of the modulus in crystallizing films.

A single crystal with a selected composition of a Cu–Al–Ni shape memory alloy, undergoing two martensitic phase transformations when cooling from the common parent phase, β 3 → β 3 ′ + γ 3 ′ , has been studied by adiabatic calorimetry. As the coexistence of two different martensites has a strong influence on the transformation kinetics, both the forward and the reverse phase martensitic transformation have been carefully studied by means of very low thermal rate dynamic thermograms. Temperature memory effects have been observed in the β 3 ′ transformation but not in the γ 3 ′ one. Finally, radiation-cooling procedures were used to study the forward transformation and showed the interaction between the two types of martensite variants on the nucleation processes. This last technique was found useful to evaluate the latent heat released at each individual nucleation event, throughout the transformation progress. The consequent sample self-heating alters this process, which dramatically affects the β 3 ′ / γ 3 ′ ratio and the final martensitic state.

New high-damping metal matrix composites have been developed, by embedding powders of Cu–Al–Ni shape memory alloys with two different metallic matrices (In–10 wt.%Sn and In–Sn eutectic alloys). The damping properties have been characterized using a sub-resonant torsion pendulum. High damping values were obtained in a wide range of temperature. In the present work, the influence of the matrix and the shape memory alloy particles, on the damping properties of the composites, is studied and discussed. A synergetic effect from both contributions, matrix and particles, was observed.

The martensitic transformation kinetics during partial cycling and the so-called “hammer” effect has been carefully characterized in Cu–Al–Ni shape memory alloys. These temperature memory effects were measured by adiabatic calorimetry and analyzed within the frame of a new thermodynamic model. A straightforward study of the nucleation processes explains on quantitative grounds the shift of the reverse transformation to higher temperatures and the presence of a secondary Cp peak associated to these phenomena. The optical observations support the calorimetric results. Finally, the release of the elastic energy in the martensitic state due to the different thermal cycles has been determined.

High-damping materials have attracted much attention to solve problems such as acoustic pollution, nano-scale vibration isolations in electronic industry, vibration damping in civil engineering, etc. Shape memory alloys (SMAs), which intrinsically present high-damping capacity, are considered as alternative materials to the traditionally used polymeric ones, because they present better mechanical properties at moderate temperatures. A new kind of high-damping metal matrix composites has been produced by embedding a relatively high amount (approximately 60 vol.%) of Cu–Al–Ni SMA particles with metallic matrices (In, In + Sn). The damping properties have been characterized by mechanical spectroscopy, using an inverted torsion pendulum, as a function of temperature (150–400 K), frequency (0.01–3 Hz), and strain amplitude (2 × 10 −5 to 8 × 10 −5 ). The materials exhibit internal friction higher than 0.5 in a relatively wide temperature range. The ability of matching the temperature of maximum damping, through the composition of the SMA, opens new possibilities for designing high-damping materials for specific applications.

A new sub-resonant inverted torsion pendulum has been used to measure the internal friction and dynamic modulus of an Fe–38 at.% Al alloy as a function of temperature from 600 to 1350 K and constant oscillating frequency ranging from 0.01 to 3 Hz. Two internal friction peaks and a background increasing exponentially with temperature were observed. Both peaks overlap and have different shifts to lower temperatures with decreasing frequency indicating different involved relaxation mechanisms. We measured the activation parameters of the main peak. Finally we applied a recently proposed model to remove the high-temperature internal friction background and perform a spectra de-convolution to find the parameters characterizing both relaxations. The mechanisms responsible for both relaxations are discussed.

Shape memory alloys undergo a martensitic transformation, where thermomechanical properties are basically controlled by the austenite–martensite interphases, exhibiting complex orientation relationships and irrational habit planes. They are usually determined by the phenomenological theory. In this work an experimental study of nine different habit planes and orientation relationships is first realized. Then, an analysis of the interphases in the reciprocal space shows that they cannot be univocally determined by the usual two-dimensional edge-to-edge matching method. Finally, we propose a new method, based on the three-dimensional edge-to-edge matching of dense planes across the interface, to determine the habit planes and the orientation relationships. This method requires only one selected area diffraction pattern on the edge-on interface and a three-dimensional simulation of the reciprocal lattices of both structures. The habit planes determined on CuAlNi by this method agree with the values proposed by the phenomenological theory.

A thermodynamic study, based on high-sensitivity adiabatic calorimetry, of the martensitic transformation undergone by Cu–Al–Ni shape memory alloys is presented. From the specific heat data, the thermodynamic function values, and in particular the crystal free energy, as functions of temperature, have been obtained. These results have permitted a careful estimation of the phase transformation temperatures of each β3′ martensite plate as a function of its stored elastic energy. Within this frame, the distribution density of the elastic energy states in the martensitic phase is directly derived from the specific heat data. It also permits a simple analysis of the nucleation processes and gives a convincing explanation of the temperature memory effects.

Resumen Introduccion Las enfermedades dermatologicas representan un porcentaje importante de los motivos de consulta en Atencion Primaria. En nuestro ambito la creciente demanda de consulta y la consecuente aparicion de listas de espera hace necesario establecer algun tipo de criterio para una adecuada derivacion. Pretendemos en este estudio describir las caracteristicas de la derivacion desde los centros de Atencion Primaria a las consultas de Dermatologia, asi como la correlacion existente entre el motivo de consulta y el diagnostico dermatologico final. Material y metodos Se recogen los datos de 3.164 pacientes atendidos por primera vez en nuestras consultas de Dermatologia, durante 1998, clasificandose segun el centro de Atencion Primaria de procedencia y el motivo de consulta. Se realiza un estudio de concordancia entre el motivo de consulta y el diagnostico dermatologico final, averiguando para cada caso el valor predictivo positivo, la sensibilidad diagnostica y el indice de concordancia kappa. Resultados La concordancia diagnostica global ha sido del 65,52 %. Se detecta por parte del medico de Atencion Primaria un sobrediagnostico de las enfermedades por papilomavirus y una sensibilidad diagnostica muy baja en patologias como el carcinoma basocelular y las queratosis seborreicas. Conclusiones Se hace necesario insistir en la formacion de los medicos de Atencion Primaria, en una adecuada derivacion desde los centros de Atencion Primaria y en potenciar un buen modelo de interconsulta con el especialista.

Resumen Introduccion Se ha observado en los ultimos anos un aumento en la poblacion inmigrante que acude a nuestras consultas. Pretendemos describir en el presente estudio las caracteristicas epidemiologicas dermatologicas de este grupo de poblacion en el area de salud del Hospital Miguel Servet de Zaragoza. Material y metodos Se han recogido los datos de los pacientes inmigrantes atendidos en nuestras consultas de Dermatologia durante el ano 2004. Los diagnosticos dermatologicos se han codificado segun el ICD-9-CM. El estudio estadistico se ha realizado con el programa SPSS, el gestor de base de datos Access y la hoja de calculo Excel. Resultados Se han atendido un total de 706 pacientes inmigrantes, lo que supone el 4% aproximado del total de primeras visitas, apreciandose una mayor frecuencia de mujeres, con diferencias significativas. La edad media es de 31 anos, sin que se aprecien diferencias significativas entre ambos sexos. Ecuador, Colombia, Rumania, Marruecos, Gambia, Guinea y Senegal son por este orden los paises de origen que con mas frecuencia se han detectado entre nuestros pacientes. Las enfermedades dermatologicas mas frecuentes en este grupo de poblacion han sido las de origen infeccioso, sobre todo micosis, siguiendo las de origen viral y las piodermitis asi como las enfermedades de transmision sexual, apreciandose en todas ellas una incidencia superior a la de la poblacion autoctona. Conclusiones Se hace necesario un adecuado conocimiento de la patologia dermatologica en este grupo de poblacion con el fin de realizar tanto un correcto diagnostico y tratamiento como de desarrollar medidas de prevencion de enfermedades importadas.