33 research outputs found

    Influence of Reynolds number on theoretical models for trailing vortices

    Get PDF
    We conduct direct numerical simulations for a NACA0012 airfoil at Reynolds numbers (Re) ranging from 300 to 7000 to determine the wake behavior behind this wing profile. We characterize the structure of the wing-tip vortex, finding a reasonable agreement with experimental results at Re=7000. In addition, we model the trailing vortex theoretically, thus obtaining the parameters for Batchelor’s and Moore and Saffman’s models. We compare the results of the best fitting for the axial vorticity and the azimuthal velocity, finding only small discrepancies. The main contribution of this research work is to study the evolution of these theoretical parameters as function of the Reynolds number. We observe that the wake becomes unstable at Re ≈1200, in agreement with previous results. These instabilities in the wake behind the wing produce a change in the trend of theoretical parameters (keywords: vortex dynamics, trailing vortices, theoretical models).Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Natural course of septo-optic dysplasia: Retrospective analysis of 20 cases

    Full text link
    Introducción. La displasia septoóptica (DSO) es la combinación variable de signos de disgenesia de línea media cerebral, hipoplasia de nervios ópticos y disfunción hipotálamo-hipofisaria, asociándose, a veces, con un espectro variado de malformaciones de la corteza cerebral. Objetivo. Describir la evolución natural y los hallazgos de neuroimagen en una serie de 20 pacientes diagnosticados. Pacientes y métodos. Se revisan de forma retrospectiva las características epidemiológicas, clínicas y neurroradiológicas de 20 pacientes consecutivos diagnosticados de DSO entre enero de 1985 y enero de 2010. Se analizaron los datos de tomografía computarizada, resonancia magnética craneal, electroencefalograma, potenciales evocados visuales, valoración oftalmológica, cariotipo y estudio endocrinológico. En siete pacientes, se realizó estudio del gen Homeobox HESX1. Resultados. El 60% de los casos presentaba antecedentes patológicos en el primer trimestre de gestación, con las ecografías fetales normales. Clínicamente, destacaban manifestaciones visuales (85%), alteraciones endocrinas (50%), retraso mental (60%) y crisis epilépticas (55%). Un 55% se asociaba a anomalías de migración neuronal. En un 45%, la DSO era el único hallazgo de neuroimagen. Se realizó cariotipo a todos, siendo normal. El gen HESX1 fue positivo en dos de los siete casos estudiados (ambos con DSO aislada). Ninguno con mutación en el gen HESX1 presentaba consanguinidad familiar. No se realizó estudio genético a los padres. Conclusiones. La DSO debe clasificarse como un síndrome malformativo heterogéneo, que asocia múltiples anomalías cerebrales, oculares, endocrinas y sistémicas. Las formas más graves se asocian con anomalías de la migración neuronal y de la organización cortical (AU)Introduction. Septo-optic dysplasia (SOD) is the variable combination of signs of dysgenesis of the midline of the brain, hypoplasia of the optic nerves and hypothalamus-pituitary dysfunction, which is sometimes associated with a varied spectrum of malformations of the cerebral cortex. Aims. To describe the natural history and neuroimaging findings in a series of 20 diagnosed patients. Patients and methods. We review the epidemiological, clinical and neuroimaging characteristics of 20 consecutive patients diagnosed with SOD between January 1985 and January 2010. Data obtained from computerised tomography, magnetic resonance imaging of the head, electroencephalogram, visual evoked potentials, ophthalmological evaluation, karyotyping and endocrinological studies were analysed. In seven patients, a study of the gene Homeobox HESX1 was conducted. Results. Pathological antecedents in the first three months of gestation were presented by 60% of the cases, with normal results in the foetal ultrasound scans. Clinically, the most striking features were visual manifestations (85%), endocrine disorders (50%), mental retardation (60%) and epileptic seizures (55%). Fifty-five per cent were associated to abnormal neuronal migration. In 45%, SOD was the only finding in the neuroimaging scans. Karyotyping was performed in all cases, the results being normal. Gene HESX1 was positive in two of the seven cases studied (both with isolated SOD). None of those with mutation in gene HESX1 presented familial consanguinity. No gene study was conducted with the parents. Conclusions. SOD must be classified as a heterogeneous malformation syndrome, which is associated to multiple brain, ocular, endocrine and systemic anomalies. The most severe forms are associated with abnormal neuronal migration and cortical organisation (AU

    Chitosan as a Tool for Sustainable Development: A Mini Review

    Get PDF
    New developments require innovative ecofriendly materials defined by their biocompatibility, biodegradability, and versatility. For that reason, the scientific society is focused on biopolymers such as chitosan, which is the second most abundant in the world after cellulose. These new materials should show good properties in terms of sustainability, circularity, and energy consumption during industrial applications. The idea is to replace traditional raw materials with new ecofriendly materials which contribute to keeping a high production rate but also reducing its environmental impact and the costs. The chitosan shows interesting and unique properties, thus it can be used for different purposes which contributes to the design and development of sustainable novel materials. This helps in promoting sustainability through the use of chitosan and diverse materials based on it. For example, it is a good sustainable alternative for food packaging or it can be used for sustainable agriculture. The chitosan can also reduce the pollution of other industrial processes such as paper production. This mini review collects some of the most important advances for the sustainable use of chitosan for promoting circular economy. Hence, the present review focuses on different aspects of chitosan from its synthesis to multiple applications.Author wants to thank the Erasmus+ KA107 scholarship

    Myofascial Trigger Points, Pain, Disability, and Sleep Quality in Patients with Chronic Nonspecific Low Back Pain

    Get PDF
    [EN] Objective: To investigate the difference in the presence of trigger points (TrPs) between patients with chronic nonspecific low back pain (LBP) and healthy people, and to determine the relationship of TrPs with the intensity of ongoing pain, disability, and sleep quality. Design: A cross-sectional study. Setting: The role of TrPs in LBP has not been determined. Patients: Forty-two patients with nonspecific LBP (50% women), aged 23-55 years old, and 42 age- and sex-matched controls participated. Outcome measures: TrPs were bilaterally explored within the quadratus lumborum, iliocostalis lumborum, psoas, piriformis, gluteus minimus, and gluteus medius muscles in a blinded design. TrPs were considered active if the subject recognized the local and referred pain as familiar symptoms, and TrPs were considered latent if the pain was not recognized as a familiar symptom. Pain measures were collected with a numerical pain rate scale, disability was assessed with the Roland-Morris questionnaire, and sleep quality was determined with the Pittsburgh Sleep Quality Index. Results: Patients with nonspecific LBP exhibited a greater disability and worse sleep quality than healthy controls (P < 0.001). Patients with nonspecific LBP exhibited a mean of 3.5 ± 2.3 active TrPs. Further, patients with nonspecific LBP showed a greater (P < 0.001) number of latent TrPs (mean: 2.0 ± 1.5) than healthy controls (mean: 1.0 ± 1.5). Active TrPs in the quadratus lumborum, iliocostalis lumborum, and gluteus medius muscles were the most prevalent in patients with nonspecific LBP. A greater number of active TrPs was associated with higher pain intensity (rs = 0.602; P < 0.001) and worse sleep quality (rs = 0.338; P = 0.03). Conclusions: The local and referred pain elicited by active TrPs in the back and hip muscles contributes to pain symptoms in nonspecific LBP. Patients had higher disability and worse sleep quality than controls. The number of active TrPs was associated with pain intensity and sleep quality. It is possible that a complex interaction among these factors is present in patients with nonspecific LBP

    Concentration Effect over Thermoresponse Derived from Organometallic Compounds of Functionalized Poly(N-isopropylacrylamide-co-dopamine Methacrylamide)

    Get PDF
    The functionalization of smart polymers is opening a new perspective in catalysis, drug carriers and biosensors, due to the fact that they can modulate the response regarding conventional devices. This smart response could be affected by the presence of organometallic complexes in terms of interactions which could affect the physical chemical properties. In this sense, the thermoresponsive behavior of copolymers based on N-isopropylacrylamide (NIPAM) could be affected due to the presence of hydrophobic groups and concentration effect. In this work, the functionalization of a copolymer based on NIPAM and dopamine methacrylamide with different amounts of bis(cyclopentadienyl)titanium (IV) dichloride was carried out. The resulting materials were characterized, showing a clear idea about the mechanism of functionalization through FTIR spectroscopy. The thermoresponsive behavior was also studied for various polymeric solutions in water by UV&#8211;vis spectroscopy and calorimetry. The hydrophobic interactions promoted by the organometallic complex could affect the transition associated with the lower critical solution temperature (LCST), specifically, the segments composed by pure NIPAM. That fact would explain the reduction of the width of the LCST-transition, contrary to what could be expected. In addition, the hydrophobicity was tested by the contact angle and also DNA interactions.The authors want to thank the funding obtained from Ministerio de Ciencia, Innovación y Universidades (MCIU), Agencia Estatal de Investigación (AEI) and Fondo Europeo de Desarrollo Regional (FEDER, UE) through the project: PGC2018-095364-B-I00

    Nuevos fármacos antiepilépticos en Pediatría

    Get PDF
    Se estima que unos 70 millones de personas padecen epilepsia a nivel mundial de los cuales más de la mitad son niños, en los que la prevalencia estimada se sitúa en torno al 0,5-0,8%. Aunque existen diversas terapias, el tratamiento de la epilepsia se basa mayoritariamente en fármacos, que en función de su año de comercialización se clasifican como de primera, segunda o tercera generación. En el presente artículo se revisan las principales características de los fármacos antiepilépticos de última generación (lacosamida, acetato de eslicarbazepina, brivaracetam, perampanel, retigabina, everolimus y cannabidiol) que, con excepción de la retigabina (ya no está comercializada), se consideran seguros y efectivos en población pediátrica. El everolimus y el cannabidiol tienen indicaciones muy concretas (esclerosis tuberosa, síndrome de Dravet y síndrome de Lennox Gastaut) mientras que el resto están indicados en el manejo de crisis de origen focal en niños a partir de 4 años. Estas nuevas moléculas han sido desarrolladas para aportar un perfil farmacocinético y de tolerancia superior a los fármacos previamente disponibles y es previsible que a medida que aumente su uso, se vaya perfilando y ampliando su verdadero potencial. Además, por primera vez en epileptología pediátrica, se ha utilizado la extrapolación de datos de efectividad en adultos (junto con estudios de seguridad y farmacocinética específicos en población pediátrica), para acelerar la aprobación de uso en población infantil.It is estimated that about 70 million people all over the world suffer from epilepsy, half of which are children, in whom the prevalence is around 0.5 to 0.8%. Although there are several therapies, the treatment of epilepsy is based mainly on drugs, which, depending on the year of coming onto the market are classified as first, second, or third generation. In this article, a description is presented on the main characteristics of the latest generation of antiepileptic drugs (lacosamide, eslicarbazepine acetate, brivaracetam, perampanel, retigabine, everolimus and cannabidiol). These, with the exception of retigabine (is not yet on the market), are considered safe and effective in the paediatric population. Everolimus and cannabidiol have very specific indications (tuberous sclerosis, Dravet syndrome, and Lennox Gastaut syndrome), while the rest are indicated in the management of seizures of focal origin in children from 4 years-old. These new molecules have been developed in order to provide a pharmaceutical profile and tolerance superior to the previously available drugs, and it is forecast that as their use increases, their true potential and profile will widen. Furthermore, for the first time in Paediatric Epileptology,the extrapolation ofthe efficacy data in adults have been used (together with specific safety and pharmacokinetic studies in the paediatric population), in order to speed up their approval for use in the child population

    Paradigmatic de novo GRIN1 variants recapitulate pathophysiological mechanisms underlying GRIN1-related disorder clinical spectrum

    Get PDF
    Background: GRIN-related disorders (GRD), the so-called grinpathies, is a group of rare encephalopathies caused by mutations affecting GRIN genes (mostly GRIN1, GRIN2A and GRIN2B genes), which encode for the GluN subunit of the N-methyl D-aspartate (NMDA) type ionotropic glutamate receptors. A growing number of functional studies indicate that GRIN-encoded GluN1 subunit disturbances can be dichotomically classified into gain- and loss-of-function, although intermediate complex scenarios are often present. Methods: In this study, we aimed to delineate the structural and functional alterations of GRIN1 disease-associated variants, and their correlations with clinical symptoms in a Spanish cohort of 15 paediatric encephalopathy patients harbouring these variants. Results: Patients harbouring GRIN1 disease-associated variants have been clinically deeplyphenotyped. Further, using computational and in vitro approaches, we identified different critical checkpoints affecting GluN1 biogenesis (protein stability, subunit assembly and surface trafficking) and/or NMDAR biophysical properties, and their association with GRD clinical symptoms. Conclusions: Our findings show a strong correlation between GRIN1 variants-associated structural and functional outcomes. This structural-functional stratification provides relevant insights of genotypephenotype association, contributing to future precision medicine of GRIN1-related encephalo

    Circulating carotenoids are associated with favorable lipid and fatty acid profiles in an older population at high cardiovascular risk

    Get PDF
    Carotenoid intake has been reported to be associated with improved cardiovascular health, but there is little information on actual plasma concentrations of these compounds as biomarkers of cardiometabolic risk. The objective was to investigate the association between circulating plasma carotenoids and different cardiometabolic risk factors and the plasma fatty acid profile. This is a cross-sectional evaluation of baseline data conducted in a subcohort (106 women and 124 men) of an ongoing multi-factorial lifestyle trial for primary cardiovascular prevention. Plasma concentrations of carotenoids were quantified by liquid chromatography coupled to mass spectrometry. The associations between carotenoid concentrations and cardiometabolic risk factors were assessed using regression models adapted for interval-censored variables. Carotenoid concentrations were cross-sectionally inversely associated with serum triglyceride concentrations [-2.79 mg/dl (95% CI: -4.25, -1.34) and -5.15 mg/dl (95% CI: -7.38, -2.93), p-values = 0.0002 and <0.00001 in women and men, respectively], lower levels of plasma saturated fatty acids [-0.09% (95% CI: -0.14, -0.03) and -0.15 % (95% CI: -0.23, -0.08), p-values = 0.001 and 0.0001 in women and men, respectively], and higher levels of plasma polyunsaturated fatty acids [(0.12 % (95% CI: -0.01, 0.25) and 0.39 % (95% CI: 0.19, 0.59), p-values = 0.065 and 0.0001 in women and men, respectively] in the whole population. Plasma carotenoid concentrations were also associated with higher plasma HDL-cholesterol in women [0.47 mg/dl (95% CI: 0.23, 0.72), p-value: 0.0002], and lower fasting plasma glucose in men [-1.35 mg/dl (95% CI: -2.12, -0.59), p-value: 0.001]. Keywords: Mediterranean diet; PREDIMED-plus study; cardiovascular health; liquid chromatography; mass spectrometry; plasma carotenoids

    Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

    Full text link
    The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality
    corecore