Influence of the starting temperature of calorimetric measurements on the accuracy of determined magnetocaloric effect

Availability of a restricted heat capacity data range has a clear influence on the accuracy of calculated magnetocaloric effect, as confirmed by both numerical simulations and experimental measurements. Simulations using the Bean-Rodbell model show that, in general, the approximated magnetocaloric effect curves calculated using a linear extrapolation of the data starting from a selected temperature point down to zero kelvin deviate in a non-monotonic way from those correctly calculated by fully integrating the data from near zero temperatures. However, we discovered that a particular temperature range exists where the approximated magnetocaloric calculation provides the same result as the fully integrated one. These specific truncated intervals exist for both first and second order phase transitions and are the same for the adiabatic temperature change and magnetic entropy change curves. The effect of this truncated integration in real samples was confirmed using heat capacity data of Gd metal and Gd5Si2Ge2 compound measured from near zero temperatures

Nanostructuring as a Procedure to Control the Field Dependence of the Magnetocaloric Effect

In this work, the field dependence of the magnetocaloric effect of Gd bulk samples has been enhanced through nanostructuring of the material. Nanostructuring consists in multilayers preparation by alternative rf-sputtering deposition of Gd layers and Ti spacers onto glass substrates. The results obtained for the multilayers were compared to those obtained for the Gd bulk. Assuming a power law for the field dependence of the magnetic entropy change (ΔSM ∝ Hn), higher field dependences close to the transition in a wider temperature range are obtained for the multilayer material (n = 1.0) with respect to the bulk counterpart (n = 0.78). The effect of a Curie temperature distribution in the multilayer material (due to variations of the layer thickness) has been studied through numerical simulations to explain the observed field dependence of the magnetocaloric effect, obtaining a remarkable agreement between experiments and results. © 2016 Elsevier Ltd.This work was supported by the Spanish MINECO and EU- FEDER (projects MAT2013-45165-P and MAT2016-77265-R ), the PAI of the Regional Government of Andalucía, and the Ministry of Education and Science of the Russian Federation (Project No. 2582 ). L.M. Moreno-Ramírez acknowledges a FPU fellowship from the Spanish MECD. Selected measurements were performed at SGIker service of UPV-EHU. We thank A. Larrañaga for excellent technical support

Manual Moodle 3.1 para el profesor

El presente manual es el fruto del trabajo y la experiencia de los técnicos del Gabinete de Tele-Educación de la Universidad Politécnica de Madrid que desde el año 2005 vienen gestionando y prestando soporte a la herramienta Moodle para toda nuestra comunidad universitaria. Se trata de una actualización del manual realizado en 2012 para la versión 2.2. Anteriormente, este equipo realizó un manual para el profesor adaptado hasta la versión 1.9. Ese manual tenía como partida el libro “Using Moodle” y se completó con la documentación existente en su momento y las aportaciones del personal de nuestro equipo. Para tener una visión general de la información de este manual, siga leyendo la descripción que se presenta a continuación

Manual Moodle 2.4 para el profesor

El presente manual es el fruto del trabajo y la experiencia de los técnicos del Gabinete de Tele-Educación de la Universidad Politécnica de Madrid que desde el año 2005 vienen gestionando y prestando soporte a la herramienta Moodle para toda la comunidad universitaria. Se trata de una actualización del manual realizado en 2012 para la versión 2.2. Anteriormente, este equipo realizó un manual para el profesor adaptado hasta la versión 1.9. Ese manual tenía como partida el libro “Using Moodle” y se completó con la documentación existente en su momento y las aportaciones del personal de nuestro equipo. Para tener una visión general de la información de este manual, siga leyendo la descripción que se presenta a continuación

Manual Moodle 2.6 para el profesor

El presente manual es el fruto del trabajo y la experiencia de los técnicos del Gabinete de Tele-Educación de la Universidad Politécnica de Madrid que desde el año 2005 vienen gestionando y prestando soporte a la herramienta Moodle para toda la comunidad universitaria. Se trata de una actualización del manual realizado en 2012 para la versión 2.2. Anteriormente, este equipo realizó un manual para el profesor adaptado hasta la versión 1.9. Ese manual tenía como partida el libro “Using Moodle” y se completó con la documentación existente en su momento y las aportaciones del personal de nuestro equipo. Para tener una visión general de la información de este manual, siga leyendo la descripción que se presenta a continuación

Manual Moodle 2.8 para el profesor

El presente manual es el fruto del trabajo y la experiencia de los técnicos del Gabinete de Tele-Educación de la Universidad Politécnica de Madrid que desde el año 2005 vienen gestionando y prestando soporte a la herramienta Moodle para toda nuestra comunidad universitaria. Se trata de una actualización del manual realizado en 2012 para la versión 2.2. Anteriormente, este equipo realizó un manual para el profesor adaptado hasta la versión 1.9. Ese manual tenía como partida el libro “Using Moodle” y se completó con la documentación existente en su momento y las aportaciones del personal de nuestro equipo. Para tener una visión general de la información de este manual, siga leyendo la descripción que se presenta a continuación. Contenido del Manual Antes de empezar, se realiza un acercamiento a Moodle 2.8 para el profesor que ha utilizado versiones anteriores, ya que algunos aspectos presentan importantes cambios. A continuación, el contenido se divide en cuatro grandes bloques

Calculating a Drop in Carbon Emissions in the Strait of Gibraltar (Spain) from Domestic Shipping Traffic Caused by the COVID-19 Crisis

As a consequence of the COVID-19 pandemic, the Spanish government declared a State of Emergency, and domestic passenger ship traffic was restricted in Spanish ports. This manuscript presents scenarios of emissions from domestic shipping traffic in the seas of the Strait of Gibraltar (Spain) over three months of the COVID-19 pandemic. Emissions were estimated for only 90 days of the pandemic, and two scenarios were studied: emissions while vessels were berthed at the Algeciras Port and emissions as a consequence of the interruption of passenger ship transportation in the Strait of Gibraltar. To this end, the authors' own model was used, which has near zero uncertainties. This model was used for the first time in this study and takes into account both meteorological and sea condition parameters, as well as the efficiency of the propulsion system. The manuscript concentrates on the emissions of greenhouse gases (GHGs), nitrogen oxides (NOx), sulphur oxides (SOx), carbon dioxide (CO2), and particulate matter (PM) from six Ro-Pax ships that ceased to operate. The main finding is that as a consequence of the pandemic, reductions of up to 12% were found in the Strait of Gibraltar in all the pollutants and GHGs when taking into account all international traffic, while the decrease in emissions from domestic traffic only reached 51%

Transient Changes in the Plasma of Astrocytic and Neuronal Injury Biomarkers in COVID-19 Patients without Neurological Syndromes

The levels of several glial and neuronal plasma biomarkers have been found to increase during the acute phase in COVID-19 patients with neurological symptoms. However, replications in patients with minor or non-neurological symptoms are needed to understand their potential as indicators of CNS injury or vulnerability. Plasma levels of glial fibrillary acidic protein (GFAP), neurofilament light chain protein (NfL), and total Tau (T-tau) were determined by Single molecule array (Simoa) immunoassays in 45 samples from COVID-19 patients in the acute phase of infection [moderate (n = 35), or severe (n = 10)] with minor or non-neurological symptoms; in 26 samples from fully recovered patients after ~2 months of clinical follow-up [moderate (n = 23), or severe (n = 3)]; and in 14 non-infected controls. Plasma levels of the SARS-CoV-2 receptor, angiotensin-converting enzyme 2 (ACE2), were also determined by Western blot. Patients with COVID-19 without substantial neurological symptoms had significantly higher plasma concentrations of GFAP, a marker of astrocytic activation/injury, and of NfL and T-tau, markers of axonal damage and neuronal degeneration, compared with controls. All these biomarkers were correlated in COVID-19 patients at the acute phase. Plasma GFAP, NfL and T-tau levels were all normalized after recovery. Recovery was also observed in the return to normal values of the quotient between the ACE2 fragment and circulating full-length species, following the change noticed in the acute phase of infection. None of these biomarkers displayed differences in plasma samples at the acute phase or recovery when the COVID-19 subjects were sub-grouped according to occurrence of minor symptoms at re-evaluation 3 months after the acute episode (so called post-COVID or "long COVID"), such as asthenia, myalgia/arthralgia, anosmia/ageusia, vision impairment, headache or memory loss. Our study demonstrated altered plasma GFAP, NfL and T-tau levels in COVID-19 patients without substantial neurological manifestation at the acute phase of the disease, providing a suitable indication of CNS vulnerability; but these biomarkers fail to predict the occurrence of delayed minor neurological symptoms

Ultrasonic evidence of an uncorrelated cluster formation temperature in manganites with first-order magnetic transition at T_C

Ultrasonic attenuation and phase velocity measurements have been carried out in the ferromagnetic perovskites La_{2/3}Ca_{1/3}MnO_3 and La_{2/3}Sr_{1/3}MnO_3. Data show that the transition at the Curie temperature, T_C, changes from first- to second-order as Sr replaces Ca in the perovskite. The compound with first-order transition shows also another transition at a temperature T* > T_C. We interpret the temperature window T_C < T < T* as a region of coexistence of a phase separated regime of metallic and insulating regions, in the line of recent theoretical proposals.Comment: 4 pages, 2 figure