170,287 research outputs found
El Diccionario valenciano-castellano (1851) de Josep Escrig i la proposta de recuperació del model ortogràfic tradicional
No full textThe Valencian-Castilian dictionary by Josep Escrig, Diccionario valenciano-castellano (1851), has been one of the most condemned works in the history of the Catalan lexicography. However, current studies have shown that most of the expressed opinions about it are the result of prejudices, and reveal a questionable rigour in the research. In this paper, we aim at commenting on the traditional orthographical proposal of Josep Escrig’s dictionary (1851), which represents an additional merit of this work and comes to reassert its value.El Diccionario valenciano-castellano (1851) de Josep Escrig ha estat una de les obres més vituperades en les distintes investigacions sobre la història de la lexicografia catalana. Ara bé, diversos estudis actuals mostren que moltes d’aquestes idees són fruit de prejudicis i amaguen un examen de l’obra poc rigorós. En aquest article comentarem la proposta ortogràfica tradicional del diccionari de Josep Escrig (1851), un mèrit més de l’obra que contribueix a refermar-ne els valors
DMT Optimal Cooperative Protocols with Destination-Based Selection of the Best Relay
No full textWe design a cooperative protocol in the context of wireless mesh networks in order to increase the reliability of wireless links. Destination terminals ask for cooperation when they fail in decoding data frames transmitted by source terminals. In that case, each destination terminal D calls a specific relay terminal B with a signaling frame to help its transmission with source terminal S. To select appropriate relays, destination terminals maintain tables of relay terminals, one for each possible source address. These tables are constituted by passively overhearing ongoing transmissions. Hence, when cooperation is needed between S and D, and when a relay B is found by terminal D in the relay table associated with terminal S, the destination terminal sends a negative acknowledgment frame that contains the address of B. When the best relay B has successfully decoded the source message, it sends a copy of the data frame to D using a selective decode-andforward transmission scheme. The on-demand approach allows maximization of the spatial multiplexing gain and the cooperation of the best relay allows maximization of the spatial diversity order. Hence, the proposed protocol achieves optimal diversitymultiplexing trade-off performance. Moreover, this performance is achieved through a collision-free selection process
Splitting algorithm for DMT optimal cooperative MAC protocols in wireless mesh networks
No full textA cooperative protocol for wireless mesh networks is proposed in this paper. The protocol implements both on-demand relaying and a selection of the best relay terminal so only one terminal is relaying the source message when cooperation is needed. Two additional features are also proposed. The best relay is selected with a splitting algorithm. This approach allows fast relay selection within less than three time-slots, on average. Moreover, a pre-selection of relay candidates is performed prior to the splitting algorithm. Only terminals that are able to improve the direct path are pre-selected. So efficient cooperation is now guaranteed. We prove that this approach is optimal in terms of diversity-multiplexing trade-off. The protocol has been designed in the context of Nakagami-mfading channels. Simulation results show that the performance of the splitting algorithm does not depend on channel statistics
Caracterización fenotípica y molecular de las neuropatías hereditarias en la infancia y la adolescencia
No full textANTECEDENTES: La mayoría de las polineuropatías en la infancia son genéticamente determinadas, estimándose alrededor del 70-90% del total de neuropatías. Este grupo de neuropatías hereditarias (NH) comprende las NH tipo Charcot-Marie-Tooth y los síndromes hereditarios complejos bien sean enfermedades neurodegenerativas o errores innatos del metabolismo en los que la polineuropatía es una de sus características. La literatura médica es escasa en estudios de neuropatías hereditarias en población pediátrica, lo que puede ser atribuible a la escasez de programas nacionales e internacionales de bases de datos y escalas uniformes de evaluación pediátricas de aplicación generalizada.
OBJETIVOS: El objetivo principal es la caracterización genética y fenotípica de una serie de pacientes menores de 20 años con NH incluyendo la búsqueda de nuevos genes causantes. Los objetivos secundarios son: determinar la variabilidad de la gravedad de los distintos tipos de NH y estimar la sensibilidad de la escala CMTPedS como medida de progresión en las distintas NH.
METODOLOGÍA: Se trata de un estudio descriptivo longitudinal de 3 años de duración de una serie hospitalaria reclutados y valorados de forma prospectiva entre septiembre 2017 y septiembre de 2020 en la Unidad de Enfermedades Neuromusculares y Neuropediatría del Hospital Universitario y Politécnico La Fe (Valencia, España). Se incluyeron solo los pacientes que tenían menos de 20 años en el momento del inicio del estudio y contaban con un diagnóstico definitivo de neuropatía periférica de origen genético, aunque no se conociese el defecto genético causal tanto los casos índices como los secundarios (algún progenitor o hermano/a afectos). Los pacientes fueron estudiados desde el punto de vista clínico, neurofisiológico, de neuroimagen, de discapacidad (con la escala CMTPedS) y genético siguiendo los protocolos reflejados en la presente tesis.
Para el estudio centrado en la utilidad de la escala CMTPedS en las formas motoras puras, se contó además con la aportación de pacientes por parte del grupo de investigación en neuropatías hereditarias en edades pediátricas de The Children’s Hospital at Westmead (NSW, Australia). Los criterios de inclusión y exclusión que debían cumplir los pacientes procedentes de estos dos centros eran los mismos.
RESULTADOS: Se estudió un total de 110 pacientes con NH que en el momento del inicio tenían menos de 20 años. La mayoría pertenecen a la cohorte de pacientes remitidos al Hospital Universitario y Politécnico La Fe mientras que 8 de ellos fueron aportados por The Children’s Hospital at Westmead. De los 102 pacientes procedentes del Hospital Universitario y Politécnico La Fe, tres presentaron un fenotipo tan único y compartían el mismo genotipo TRMT5 que fueron descritos en un extenso trabajo aparte (Argente-Escrig et al., 2022). Así pues, 99 pacientes fueron los reflejados en el trabajo Argente-Escrig et al., 2021a. De estos 99 (59 hombres), 14 debutaron con neuropatía motora hereditaria distal (NHMd) y 85 debutaron con una forma sensitivomotora (NHSM) con 2/3 de subtipo desmielinizantes (Argente-Escrig et al., 2021a). El diagnóstico genético se logró en el 79,5% de las familias, con una tasa de detección de mutaciones en las formasdesmielinizantes (88,7%) y axonales (89,5%), significativamente mayor que en las familias NHMd (18,2%). CMT1A fue el subtipo más frecuente (n = 37), seguido de los que tienen mutaciones heterocigóticas en los genes GDAP1 (n = 9) o GJB1 (n = 8). Se identificaron mutaciones en otros 15 genes, incluyendo una nueva variante patogénica en el gen ATP1A1 (Argente-Escrig et al., 2021a).
La cohorte de 22 pacientes con NHMd (13 mujeres) de 19 familias procedió de los dos centros universitarios (Argente-Escrig et al., 2021b). 14 personas fueron sintomáticas en el primer año de vida. La discapacidad intelectual estuvo presente en 6 individuos y se observaron signos de motoneurona superior en 8. Se encontraron variantes patogénicas en 9 familias, más frecuentemente en BICD2 (BICD2-4, DYNC1H1-2,MFN2-2, GARS1-1). Se identificó una nueva variante patogénica en el gen GARS1 (Argente-Escrig et al., 2021b).
La CMTpedS detectó una progresión significativa de la enfermedad en todos los subtipos genéticos de NHSM (Argente-Escrig et al., 2021a), a un ritmo de 1,84 (±3,7) durante 1 año (p < 0,0005, n = 62) y una tasa de 3,6 (± 4,4: p < 0,0005, n = 45) a los 2 años. También se detectó un empeoramiento significativo para CMT1A al año (1,7 ± 3,6, p < 0,05) y a los 2 años (4,2 ± 4,3, p < 0,0005). En las NHMd, la puntuación total de la CMTPedS a lo largo de 1 año se deterioró, en promedio, 1,5 puntos (DE 3,7) o 9% (n = 12), con variabilidad significativa en la tasa de progresión dentro de la cohorte (Argente-Escrig et al., 2021b).
Finalmente, se fenotipa en profundidad las neuropatías asociadas a dos genes distintos: FGD4 y TRMT5. Los dos pacientes hermanos portadores de las variantes patogénicas c.514delG (p.Ala172Glnfs*28) y c.2211dupA (Ala738Serfs*5) en el gen FGD4 debutaron en la adolescencia y mostraron un fenotipo muy leve a diferencia de lo publicado previamente (Argente-Escrig et al., 2019). La proteína truncada p.Ala738Serfs*5 puede haber conservado parcialmente la actividad de FGD4 ya que se conservan los principales dominios funcionales. Las mutaciones recesivas en el gen TRMT5 en tres pacientes procedentes de tres familias distintas se asociaron con un fenotipo no descrito previamente (Argente-Escrig et al., 2022). Se presentaron con retraso global del desarrollo, neuropatía desmielinizante de predominio sensitivo de inicio congénito o infantil, signos piramidales, ataxia cerebelosa leve y ausencia de un perfil bioquímico compatible con una deficiencia de OXPHOS. El análisis patológico rutinaria de músculo y nervio en estos pacientes resultó aparentemente normal mientras que el estudio ultraestructural estaba claramente alterado.
CONCLUSIONES: Nuestra serie pediátrica presenta características diferenciadoras con otras cohortes descritas por la mayor proporción de portadores heterocigotos en el gen GDAP1. La afectación del tracto piramidal y la cognitiva son frecuentes en las formas motoras puras en la edad pediátrica. Se confirmó la progresión de las NHSM a los dos años de seguimiento medida con la CMTPedS, y como novedad se detectó que la CMTPedS es sensible al cambio también en el primer año de seguimiento de las NHSM. Los presentes datos apoyan a la escala CMTPedS como una medida de discapacidad sensible a la progresión al año también en las formas motoras y nuestro estudio apunta a que la CMTpedS se puede adaptar a los pacientes con formas motoras. El fenotipado en profundidad y el exhaustivo análisis genético realizado nos ayudan a comprender los mecanismos patogénicos asociados a las diferentes variantes y su influencia en el fenotipo final. Las muestras ultraestructurales de músculos y nervios pueden indicar una etiología mitocondrial en casos en que las imágenes histopatológicas de rutina parecen normales.BACKGROUND: Most polyneuropathies in childhood are genetically determined, with an estimated 70-90% of all neuropathies. Inherited peripheral neuropathies (IPN) include Charcot-Marie-Tooth disease and complex hereditary syndromes, whether they are neurodegenerative diseases or inborn errors of metabolism in which polyneuropathy is one of their characteristics. Medical literature is scarce on studies of IPN in the pediatric population, which may be attributable to the short supply of national and international database programs and uniform pediatric evaluation scales for general application.
OBJECTIVES: The main objective is the genetic and phenotypic characterization of a series of IPN patients under 20 years of age, including the search for new causative genes. The secondary objectives are the following: to determine the variability of the severity of the different types of IPN and to estimate the sensitivity of the CMTPedS scale as a measure of progression in the different IPN.
METHODS: This is a 3-year longitudinal descriptive study of a hospital-based series prospectively recruited and assessed between September 2017 and September 2020 in the Neuromuscular Diseases and Child Neurology Unit of the Hospital Universitario y Politécnico La Fe (Valencia, Spain). Only patients who were under 20 years of age at the start of the study and had a definitive diagnosis of peripheral neuropathy of genetic origin were included, even if the causal genetic defect was not known, both in index cases and in secondary cases (either parent or affected sibling). Patients were studied from the clinical, neurophysiological, neuroimaging, disability (with the CMTPedS scale) and genetic perspective following the protocols reflected in this thesis.
The research group on inherited neuropathies at The Children's Hospital at Westmead (NSW, Australia) contributed with patients with pure motor IPN for the study on the utility of the CMTPedS scale in pure motor forms. The inclusion and exclusion criteria that patients from these two centers had to meet were the same.
RESULTS: A total of 110 patients with IPN who were under 20 years old at onset were studied. Most belonged to the cohort of patients referred to Hospital Universitario y Politécnico La Fe, while 8 of them were contributed by The Children's Hospital at Westmead. Of the 102 patients from the Hospital Universitario y Politécnico La Fe, three presented such a unique phenotype and shared the same TRMT5 genotype that they were described in an extensive separate study (Argente-Escrig et al., 2022). Thus, 99 patients were reflected in the study Argente-Escrig et al., 2021a. Of these 99 (59 male), 14 presented with distal hereditary motor neuropathy (dHMN) and 85 had a sensorimotor form with 2/3 of the demyelinating subtype (Argente-Escrig et al., 2021a). Genetic diagnosis was achieved in 79.5% of families, with a detection rate of mutations in demyelinating forms (88.7%) and axonal forms (89.5%), significantly higher than in dHMN families (18.2%). CMT1A was the most frequent subtype (n = 37), followed by those with heterozygous mutations in the GDAP1(n = 9) or GJB1 (n = 8) genes. Mutations in another 15 genes were identified, including a new pathogenic variant in the ATP1A1 gene (Argente-Escrig et al., 2021a).
The cohort of 22 dHMN patients (13 female) from 19 families came from the two teaching hospitals (Argente-Escrig et al., 2021b). 14 people were symptomatic in the first year of life. Intellectual disability was present in 6 individuals and upper motor neuron signs were seen in 8. Pathogenic variants were found in 9 families, most frequently in BICD2 (BICD2-4, DYNC1H1-2, MFN2-2, GARS1-1). A new pathogenic variant in the GARS1gene was identified (Argente-Escrig et al., 2021b).
The CMTpedS detected significant disease progression in all sensorimotor genetic subtypes (Argente-Escrig et al., 2021a), at a rate of 1.84 (±3.7) over 1 year (p < 0.0005, n = 62) and a rate of 3.6 (± 4.4: p < 0.0005, n = 45) at 2 years. Significant worsening was also detected for CMT1A at 1 year (1.7 ± 3.6, p < 0.05) and at 2 years (4.2 ± 4.3, p < 0.0005). In the dHMN, the CMTPedS total score over 1 year deteriorated, on average, 1.5 points (SD 3.7) or 9% (n = 12), with significant variability in the rate of progression within 1 year of follow-up (Argente-Escrig et al., 2021b).
Finally, neuropathies associated with two different genes are phenotyped in depth: FGD4 and TRMT5. The two sibling patients who were carriers of the pathogenic variants c.514delG (p.Ala172Glnfs*28) and c.2211dupA (Ala738Serfs*5) in the FGD4 gene had their onset in adolescence and showed a very mild phenotype in contrast to what was previously published (Argente -Escrig et al., 2019). The p.Ala738Serfs*5 truncated protein may have partially conserved FGD4 activity since the main functional domains are preserved. Recessive mutations in the TRMT5 gene in three patients from three different families were associated with a phenotype not previously described (Argente-Escrig et al., 2022). They presented with global developmental delay, predominantly sensory demyelinating neuropathy of congenital or infantile onset, pyramidal signs, mild cerebellar ataxia, and no biochemical profile consistent with OXPHOS deficiency. The routine pathological analysis of muscle and nerve in these patients was apparently normal while the ultrastructural study was clearly abnormal.
CONCLUSIONS: Our pediatric series presents differentiating characteristics with other cohorts by the higher proportion of heterozygous carriers in the GDAP1 gene. Pyramidal tract and cognitive involvement are frequent in the pure motor forms in the pediatric population. The progression of the sensorimotor forms was confirmed at two years of follow-up measured with the CMTPedS, and as a novelty it was detected that the CMTPedS is sensitive to change also in the first year of follow-up. The present data support the CMTPedS scale as a measure of disability sensitive to progression at one year also in motor forms, and our study suggests that a scale modelled on CMTPedS might be useful for pediatric patients with motor forms. The in-depth phenotyping and exhaustive genetic analysis carried out help us to understand the pathogenic mechanisms associated with the different variants and their influence on the final phenotype. Ultrastructural muscle and nerve specimens may point to a mitochondrial etiology in cases where routine histopathologic imaging appears normal
Density-based uncertainty quantification in a generalized Logistic-type model
No full textThis work has been supported by the Spanish Agencia Estatal de Investigacion (AEI) and Fondo Europeo de Desarrollo Regional (FEDER UE) grant ID2020-115270GB-I00.Bevia-Escrig, V.; Burgos-Simon, C.; Cortés, J.; Villanueva Micó, RJ. (2021). Density-based uncertainty quantification in a generalized Logistic-type model. Universitat Politècnica de València. 1-6. https://riunet.upv.es/handle/10251/182200S1
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Mitomycin C in highly myopic eyes - Author reply
No full textOphthalmology. 2005 Feb;112(2):208-18; discussion 219.
Mitomycin C modulation of corneal wound healing after photorefractive keratectomy in highly myopic eyes.
Gambato C, Ghirlando A, Moretto E, Busato F, Midena E.
SourceRefractive Surgery Service and Antimetabolite Therapy Research Unit, Department of Ophthalmology, University of Padova, Padova, Italy.
Abstract
PURPOSE: To evaluate the role of topical mitomycin C in corneal wound healing (CWH) after photorefractive keratectomy (PRK) in highly myopic eyes.
DESIGN: Prospective, double-masked, randomized clinical trial.
PARTICIPANTS: Seventy-two eyes of 36 patients affected by high (>7 diopters) myopia.
METHODS: In each patient, one eye was randomly assigned to PRK with intraoperative topical 0.02% mitomycin C application, and the fellow eye was treated with a placebo. Postoperatively, mitomycin C-treated eyes received artificial tears (3 times daily, tapered in 3 months), whereas the fellow eye was treated with fluorometholone sodium 2% and artificial tears (3 times daily, tapered in 3 months).
MAIN OUTCOME MEASURES: Uncorrected visual acuity (UCVA) and best-corrected visual acuity (BCVA), contrast sensitivity, manifest refraction, and biomicroscopy. Contrast sensitivity was determined using the Pelli-Robson chart. Corneal confocal microscopy documented CWH.
RESULTS: Mean follow-up was 18 months (range, 12-36). No side effects or toxic effects were documented. At 12-month follow-up examination, UCVAs (logarithm of the minimum angle of resolution) were 0.4+/-0.48 and 0.5+/-0.53 (P = .03) in mitomycin C-treated eyes and corticosteroid-treated eyes, respectively. At 1 year, corneal haze developed in 20% of corticosteroid-treated eyes, versus 0% of mitomycin C-treated eyes. At 12, 24, and 36 months, corneal confocal microscopy showed activated keratocytes and extracellular matrix significantly more evident in untreated eyes (Ps = 0.004, 0.024, and 0.046, respectively).
CONCLUSION: Topical intraoperative application of 0.02% mitomycin C can reduce haze formation in highly myopic eyes undergoing PRK.
Comment in
Ophthalmology. 2006 Feb;113(2):357; author reply 357-8
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Optimal Cooperative MAC Protocol with Efficient Selection of Relay Terminals
No full textA new cooperative protocol is proposed in the context of wireless mesh networks. The protocol implements ondemand
cooperation, i.e. cooperation between a source terminal
and a destination terminal is activated only when needed. In that case, only the best relay among a set of available terminals is re-transmitting the source message to the destination terminal. This typical approach is improved using three additional features. First, a splitting algorithm is implemented to select the best relay. This ensures a fast selection process. Moreover, the duration of the selection process is now completely characterized.
Second, only terminals that improve the outage probability of the direct link are allowed to participate to the relay selection. By this means, inefficient cooperation is now avoided. Finally, the destination terminal discards the source message when it fails to decode it. This saves processing time since the destination terminal does not need to combine the replicas of the source message: the one from the source terminal and the one from the best relay. We prove that the proposed protocol achieves an optimal performance in terms of Diversity-Multiplexing Tradeoff
(DMT)
On-Demand Cooperation MAC Protocols with Optimal Diversity-Multiplexing Tradeoff
No full textThis paper presents access protocols with optimal Diversity-Multiplexing Tradeoff (DMT) performance in the context of IEEE 802.11-based mesh networks. The protocols are characterized by two main features: on-demand cooperation and selection of the best relay terminal. The on-demand characteristic refers to the ability of a destination terminal to ask for cooperation when it fails in decoding the message transmitted by a source terminal. This approach allows maximization of the spatial multiplexing gain. The selection of the best relay terminal allows maximization of the diversity order. Hence, the optimal DMT curve is achieved with these protocols
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