Ultra low range sidelobe level pulse compression waveform design for spaceborne meteorological radars.

Meteorological measurements from spaceborne radars present several advantages over current passive techniques, due to the radar capability to discriminate backscattered energy in range. However, the system configuration imposes stringent design requirements in order to guarantee cloud and rain detectability, in particular on the radar waveform. Since power is severely restricted on board a satellite, it is necessary to achieve an efficient range resolution with low transmitted power requirements. Pulse compression theory solves the previous conflicting demand, but the transmitted signal needs to be carefully designed in order to allow the significantly large dynamic range (between 60 and 80 dB depending on the type of meteorological target) needed to carry out the measurements. Several pulse compression range sidelobe reduction techniques of differing natures have been investigated and reported in the literature during the past 50 years. A detailed survey of the most relevant range sidelobe supression procedures has been carried out in order to identify the most suitable frequency modulation candidates which are potentially capable of meeting the stringent specifications of spaceborne radar meteorology. Novel pulse compression waveform design techniques have also been developed, employing linear FM predistortion functions and asymmetric frequency modulation laws, which provide excellent performance in terms of range sidelobe level (below -60 dB) and Doppler tolerance. Different options for the provision of a rain mode for the RA-2 Radar Altimeter (due to fly on European Space Agency ENVISAT satellite) are described, based on altimetry linear FM full-deramp technique concepts. Finally, amplitude modulated pulse compression waveform design alternatives are analysed for the MACSIM radar (Millimetre wave Active Cloud Structure Imaging Mission, European Space Agency Pre Phase A Study), which allow to measure different type of clouds within the Mission required radiometric resolution accuracy

In the shoes of accounting students: Perceptions of the skills needed for a successful career

Students are an important stakeholder group in higher education institutions (HEIs). This paper aims to examine students’ perceptions of the most important skills for a successful career in the accounting profession, and to identify how these perceptions vary among students with different academic profiles. Focusing on undergraduate and masters students, the analysis of the data indicate that perceptions differ according to students’ educational accounting profiles (level of education, professional experience, and business school excellence). The results show that students are clearly aware of the skill sets required by recruiters, but assign them varying levels of importance. The results have practical implications for academia (enhancing the perceived skills to meet objectives), recruiters (contributing to shaping the skills of aspirants), and students (matching their views with that of industry requirements).info:eu-repo/semantics/acceptedVersio

Approach of a class of discontinuous dynamical systems of fractional order: existence of the solutions

In this letter we are concerned with the possibility to approach the existence of solutions to a class of discontinuous dynamical systems of fractional order. In this purpose, the underlying initial value problem is transformed into a fractional set-valued problem. Next, the Cellina's Theorem is applied leading to a single-valued continuous initial value problem of fractional order. The existence of solutions is assured by a P\'{e}ano like theorem for ordinary differential equations of fractional order.Comment: accepted IJBC, 5 pages, 1 figur

Impaired hypoglycaemia awareness in early pregnancy increases risk of severe hypoglycaemia in the mid-long term postpartum irrespective of breastfeeding status in women with type 1 diabetes

Information regarding the postpartum period in women with type 1 diabetes (T1D) is scarce. We aim to evaluate the relation of impaired hypoglycaemia awareness (IAH) in early pregnancy and breastfeeding status (its presence and duration) with severe postpartum hypoglycaemia (SH).Retrospective cohort study of women with T1D followed during pregnancy between 2012 and 2019. Data on SH were recorded before and during pregnancy. IAH was evaluated at the first antenatal visit. Data on breastfeeding and the long-term postpartum period were collected by questionnaire and from medical records.A total of 89 women with T1D were included with a median follow-up after pregnancy of 19.2 [8.7-30.5] months. Twenty-eight (32%) women had IAH at the first antenatal visit. At discharge, 74 (83%) started breastfeeding during a median of 8 [4.4-15] months. A total of 18 (22%) women experienced ≥1 SH during postpartum. The incidence of SH significantly increased from pregestational to the gestational and post-partum period (0.09, 0.15 and 0.25 episodes/patient-year, respectively). Postpartum SH rates were comparable in breastfeeding and non-breastfeeding women (21.4% vs. 25%, respectively, p>0.05). Clarke test score at the first antenatal visit was associated with postpartum SH (for each 1-point increase: OR 1.53; 95% CI, 1.06-2.21) adjusted for confounders. No other diabetes and pregnancy-related variables were identified as predictors of SH in this period.SH are common in the long-term postpartum period independently of breastfeeding. Assessing IAH in early pregnancy could identify those at an increased risk of SH in the postpartum period.Copyright © 2022 SEEN and SED. Published by Elsevier España, S.L.U. All rights reserved

Pulsed Radiofrequency Rhizotomy of the Genicular Nerves of the Knee Guided by Radioscopy and Ultrasonography: Step-By-Step Technique

Osteoarthritis (OA) of the knee is highly prevalent and causes pain, stiffness, and harms the quality of life of millions of patients. Scientific evidence about radiofrequency ablation or rhizotomy of genicular nerves has been presented with increasing frequency in the literature for the treatment of chronic pain related to knee OA as an alternative to total knee arthroplasty. The main indication for this procedure is symptomatic OA unresponsive to conservative treatment, regardless of the disease evolution, although more common indications are in Kellgren-Lawrence grade III or IV, in post-total knee arthroplasty residual pain without an identified cause, in patients with comorbidities and high surgical risk, and those who do not want to undergo surgery. The aim of this study is to describe the step-by-step rhizotomy technique with pulsed radiofrequency of the 3 genicular nerves, guided by radioscopy and ultrasonography.info:eu-repo/semantics/publishedVersio

Los problemas de pronunciación del español en hablantes cuya lengua base es el búlgaro

Este estudio tiene como objetivo averiguar los distintos problemas de pronunciación que presentan los hablantes cuya lengua base es el búlgaros al aprender el español como lengua extranjera. Cabe destacar que la investigación se ha centrado en analizar los errores de tipo segmental. A raíz de ello, en el trabajo se menciona la importancia de la competencia fonético-fonológica dentro del campo de la enseñanza de lenguas extranjeras y se muestra una visión del tratamiento de los errores de pronunciación desde finales del siglo XIX hasta la actualidad. Asimismo, se propone un análisis contrastivo búlgaro-español que servirá de base para el estudio de los datos obtenidos.Aquest estudi té com a objectiu conèixer els diferents problemes de pronunciació que presenten els parlants natius de búlgar alhora d'aprendre l'espanyol com a llengua estrangera. Cal destacar que la investigació s'ha centrat en analitzar els errors de tipus segmental. A partir d'això, en el treball s'esmenta la importància de la competència fonètico-fonològica dins del camp de l'ensenyament de llengües estrangeres i es mostra una visió del tractament dels errors de pronunciació des de finals del segle XIX fins a l'actualitat. Així mateix, es proposa una anàlisi contrastiva búlgar-espanyol que serveix de base per l'estudi de les dades obtingude

Variación léxica y semántica cognitiva : las designaciones de las actividades lúdicas en los atlas lingüísticos

El presente trabajo de investigación tiene como objetivo principal el estudio del léxico del campo semántico de los juegos, en concreto, de dos de las actividades lúdicas que aparecen en todos los atlas lingüísticos publicados para el español europeo (ALEA ALEICan, ALeCMan, ALEANR, ALECant y ALCyL) y que presentan un alto grado de variación designativa, llevar a cuestas y llevar a hombros. El examen individual de los conceptos se ha realizado desde una perspectiva motivacional, dialectal y cognitiva. El análisis multidisciplinar ha permitido obtener una visión global de los datos a través de la cual se han determinado los mecanismos y motivos lingüístico-cognitivos que generan la variación léxica.El present treball de recerca té com a objectiu principal l'estudi del lèxic del camp semàntic dels jocs, en concret, de dues de les activitats lúdiques que apareixen en tots els atles lingüístics publicats en l'espanyol europeu (ALEA ALEICan, ALeCMan, ALEANR, ALECant y ALCyL) i que presenten un alt grau de variació geolèxica, llevar cuestas i llevar a hombros. L'anàlisi individual dels dos conceptes s'ha realitzat des d'una perspectiva motivacional, dialectal i cognitiva. L'anàlisi multidisciplinari ha permès obtenir una visió global de les dades a través de la qual s'han determinat els mecanismes i motius lingüístics y cognitius que generen la variació lèxica

Correlation between human ether-a-go-go-related gene channel inhibition and action potential prolongation

Background and Purpose: Human ether-a-go-go-related gene (hERG; Kv11.1) channel inhibition is a widely accepted predictor of cardiac arrhythmia. hERG channel inhibition alone is often insufficient to predict pro-arrhythmic drug effects. This study used a library of dofetilide derivatives to investigate the relationship between standard measures of hERG current block in an expression system and changes in action potential duration (APD) in human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs). The interference from accompanying block of Cav1.2 and Nav1.5 channels was investigated along with an in silico AP model. Experimental Approach: Drug-induced changes in APD were assessed in hiPSC-CMs using voltage-sensitive dyes. The IC50 values for dofetilide and 13 derivatives on hERG current were estimated in an HEK293 expression system. The relative potency of each drug on APD was estimated by calculating the dose (D150) required to prolong the APD at 90% (APD90) repolarization by 50%. Key Results: The D150 in hiPSC-CMs was linearly correlated with IC50 of hERG current. In silico simulations supported this finding. Three derivatives inhibited hERG without prolonging APD, and these compounds also inhibited Cav1.2 and/or Nav1.5 in a channel state-dependent manner. Adding Cav1.2 and Nav1.2 block to the in silico model recapitulated the direction but not the extent of the APD change. Conclusions and Implications: Potency of hERG current inhibition correlates linearly with an index of APD in hiPSC-CMs. The compounds that do not correlate have additional effects including concomitant block of Cav1.2 and/or Nav1.5 channels. In silico simulations of hiPSC-CMs APs confirm the principle of the multiple ion channel effects