Sistemas de predistorsión-linealización para enlaces ópticos

Ante el aumento de la demanda de conectividad de una sociedad cada vez más basada en las comunicaciones, la nueva generación de redes de transmisión apuesta claramente por la preeminencia de las tecnologías ópticas. No solo las redes troncales sino también en el acceso al hogar y en la alimentación de antenas de telefonía móvil y satélite. En este contexto en este TFC se diseñarán, se construirán y se medirán las prestaciones de circuitos de radiofrecuencia de predistorsión en el emisor y de ecualización en el receptor para la optimización de enlaces con amplificación óptica y detección directa en el receptor

Communicative context, expectations, and adaptation in prosodic production and comprehension

It is generally assumed that prosodic cues that provide linguistic information are driven primarily by the linguistic content of an utterance. However, research has shown that information from different levels of language often interact and affect the production and comprehension of an utterance (e.g., Brown-Schmidt, 2009; Remez, 1981; Ganong, 1980). If prosody operates in a similar manner to other levels of language, speakers and listeners should be sensitive to things such as communicative context, sentence structure, and listener expectations. This paper explores this possibility through a variety of studies. Part 1 investigates whether speakers have the capacity to adjust subtle acoustic-phonetic properties of the prosodic signal when they find themselves in contexts in which accurate communication is important. Thus, we examine whether the communicative context, in addition to discourse structure, modulates prosodic choices when speakers produce acoustic prominence. We manipulated the discourse status of target words in the context of a highly communicative task (i.e., working with a partner to solve puzzles in the computer game Minecraft), and in the context of a less communicative task more typical of psycholinguistic experiments (i.e., picture description). Speakers in the more communicative task produced prosodic cues to discourse structure that were more discriminable than those in the less communicative task. In a second experiment, we found that the presence or absence of a conversational partner drove some, but not all, of these effects. Together, these results suggest that speakers can modulate the prosodic signal in response to the communicative and social context. Part 2 investigates whether listener expectations influence the processing of intonational boundaries. In a boundary detection task, we manipulated a) the strength of cues to the presence of a boundary and b) whether or not a location in the sentence was a plausible location for an intonational boundary to occur given the syntactic structure. In Experiment 1, listeners are instructed to report where they heard disfluencies, even though there were no disfluencies present in the recordings. Listeners report hearing disfluencies at the locations that had intonational boundaries, and they are equally likely to report them in licensed and unlicensed locations for boundaries. This suggests that listeners can interpret prosodic cues to boundaries as disfluencies, and that their expectations as to where disfluencies might occur are more flexible than they are for where boundaries might occur. Experiment 2 makes use of a 2 trial version of the boundary detection paradigm to investigate whether listeners who reported hearing boundaries at unlicensed locations in previous studies (Buxó-Lugo & Watson, 2016) had done so because of adaptation to new types of input. The results replicate previous studies, and find no evidence for adaptation having occurred throughout those experiments. Lastly, we propose 2 studies to investigate whether listeners can adapt to new mappings between prosodic and syntactic structure

Application of a floating well concept to a latch-up-free, low-cost, smart power high-side switch technology

The aim of this brief is to present an original design methodology that permits implementing latch-up-free smart power circuits on a very simple, cost-effective technology. The basic concept used for this purpose is letting float the wells of the MOS transistors most susceptible to initiate latch-up

Metabolic effects of dialyzate glucose in chronic hemodialysis: results from a prospective, randomized crossover trial

Background. There is no agreement concerning dialyzate glucose concentration in hemodialysis (HD) and 100 and 200 mg/dL (G100 and G200) are frequently used. G200 may result in diffusive glucose flux into the patient, with consequent hyperglycemia and hyperinsulinism, and electrolyte alterations, in particular potassium (K) and phosphorus (P). This trial compared metabolic effects of G100 versus G200. Methods. Chronic HD patients participated in this randomized, single masked, controlled crossover trial (www.clinicaltrials.gov: #NCT00618033) consisting of two consecutive 3-week segments with G100 and G200, respectively. Intradialytic serum glucose (SG) and insulin concentrations (SI) were measured at 0, 30, 60, 120, 180, 240 min and immediately post-HD; P and K were measured at 0, 120, 180 min and post-HD. Hypoglycemia was defined as an SG <70 mg/dL. Mean SG and SI were computed as area under the curve divided by treatment time. Results. Fourteen diabetic and 15 non-diabetic subjects were studied. SG was significantly higher with G200 as compared to G100, both in diabetic {G200: 192.8 ± 48.1 mg/dL; G100: 154.0 ± 27.3 mg/dL; difference 38.8 [95% confidence interval (CI): 21.2-56.4] mg/dL; P < 0.001} and non-diabetic subjects [G200: 127.0 ± 11.2 mg/dL; G100 106.5 ± 10.8 mg/dL; difference 20.6 (95% CI: 15.3-25.9) mg/dL; P < 0.001]. SI was significantly higher with G200 in non-diabetic subjects. Frequency of hypoglycemia, P and K serum levels, interdialytic weight gain and adverse intradialytic events did not differ significantly between G100 and G200. Conclusion. G200 may exert unfavorable metabolic effects in chronic HD patients, in particular hyperglycemia and hyperinsulinism, the latter in non-diabetic subject

Localization of brain networks engaged by the sustained attention to response task provides quantitative markers of executive impairment in amyotrophic lateral sclerosis

Objective: To identify cortical regions engaged during the sustained attention to response task (SART) and characterize changes in their activity associated with the neurodegenerative condition amyotrophic lateral sclerosis (ALS). Methods: High-density electroencephalography (EEG) was recorded from 33 controls and 23 ALS patients during a SART paradigm. Differences in associated event-related potential peaks were measured for Go and NoGo trials. Sources active during these peaks were localized, and ALS-associated differences were quantified. Results: Go and NoGo N2 and P3 peak sources were localized to the left primary motor cortex, bilateral dorsolateral prefrontal cortex (DLPFC), and lateral posterior parietal cortex (PPC). NoGo trials evoked greater bilateral medial PPC activity during N2 and lesser left insular, PPC and DLPFC activity during P3. Widespread cortical hyperactivity was identified in ALS during P3. Changes in the inferior parietal lobule and insular activity provided very good discrimination (AUROC > 0.75) between patients and controls. Activation of the right precuneus during P3 related to greater executive function in ALS, indicative of a compensatory role. Interpretation: The SART engages numerous frontal and parietal cortical structures. SART–EEG measures correlate with specific cognitive impairments that can be localized to specific structures, aiding in differential diagnosis

Variabilité des techniques de récolte et traitement des céréales dans l'occident méditerranéen au Néolithique ancien et moyen : facteurs environnementaux, économiques et sociaux

La reconstitution des techniques agricoles préhistoriques constitue un élément fondamental pour lacompréhension du processus d'expansion de l'agriculture en Méditerranée occidentale. Dans le cadred'un projet européen rassemblant des tracéologues et des carpologues espagnols et français, nousavons, dans une première phase, étudié les méthodes de récolte des céréales pratiquées durant leNéolithique en Espagne et dans le Sud de la France, du Néolithique ancien au Néolithique moyen.L'étude des outils de récolte a permis de distinguer trois aires distinctes. Le Sud-Est de l'Espagne estcaractérisé par des faucilles courbes avec des éléments insérés obliquement dans le manche. EnCatalogne, Languedoc et Provence, la majorité des faucilles sont constituées de longues lamesemmanchées parallèlement au manche, mais d'autres modèles existent. En Espagne cantabrique, lescéréales étaient récoltées sans faucille. Nos travaux en cours explorent différents facteurs pouvantexpliquer cette variabilité : conditions environnementales, types de céréales cultivées, finalitéstechniques et alimentaires de la culture des céréales, techniques de conservation des céréales, rôle del'agriculture céréalière dans l'économie, dynamiques historiques de l'expansion et de l'adoption desinnovations néolithiques

Altered supraspinal motor networks in survivors of poliomyelitis: a cortico-muscular coherence study

Objective Poliomyelitis results in changes to the anterior horn cell. The full extent of cortical network changes in the motor physiology of polio survivors has not been established. Our aim was to investigate how focal degeneration of the lower motor neurons (LMN) in infancy/childhood affects motor network connectivity in adult survivors of polio. Methods Surface electroencephalography (EEG) and electromyography (EMG) were recorded during an isometric pincer grip task in 25 patients and 11 healthy controls. Spectral signal analysis of cortico-muscular (EEG-EMG) coherence (CMC) was used to identify the cortical regions that are functionally synchronous and connected to the periphery during the pincer grip task. Results A pattern of CMC was noted in polio survivors that was not present in healthy individuals. Significant CMC in low gamma frequency bands (30–47 Hz) was observed in frontal and parietal regions. Conclusion These findings imply a differential engagement of cortical networks in polio survivors that extends beyond the motor cortex and suggest a disease-related functional reorganisation of the cortical motor network. Significance This research has implications for other similar LMN conditions, including spinal muscular atrophy (SMA). CMC has potential in future clinical trials as a biomarker of altered function in motor networks in post-polio syndrome, SMA, and other related conditions

Functional Recovery and Serum Angiogenin Changes According to Intensity of Rehabilitation Therapy After Stroke

Angiogenina; Terapia intensiva; RehabilitaciónAngiogenin; Intensive therapy; RehabilitationAngiogenina; Teràpia intensiva; RehabilitacióBackground: Rehabilitation is still the only treatment available to improve functional status after the acute phase of stroke. Most clinical guidelines highlight the need to design rehabilitation treatments considering starting time, intensity, and frequency, according to the tolerance of the patient. However, there are no homogeneous protocols and the biological effects are under investigation. Objective: To investigate the impact of rehabilitation intensity (hours) after stroke on functional improvement and serum angiogenin (ANG) in a 6-month follow-up study. Methods: A prospective, observational, longitudinal, and multicenter study with three cohorts: strokes in intensive rehabilitation therapy (IRT, minimum 15 h/week) vs. conventional therapy (NO-IRT, <15 h/week), and controls subjects (without known neurological, malignant, or inflammatory diseases). A total of seven centers participated, with functional evaluations and blood sampling during follow-up. The final cohort includes 62 strokes and 43 controls with demographic, clinical, blood samples, and exhaustive functional monitoring. Results: The median (IQR) number of weekly hours of therapy was different: IRT 15 (15–16) vs. NO-IRT 7.5 (5–9), p < 0.01, with progressive and significant improvements in both groups. However, IRT patients showed earlier improvements (within 1 month) on several scales (CAHAI, FMA, and FAC; p < 0.001) and the earliest community ambulation achievements (0.89 m/s at 3 months). There was a significant difference in ANG temporal profile between the IRT and NO-IRT groups (p < 0.01). Additionally, ANG was elevated at 1 month only in the IRT group (p < 0.05) whereas it decreased in the NO-IRT group (p < 0.05). Conclusions: Our results suggest an association of rehabilitation intensity with early functional improvements, and connect the rehabilitation process with blood biomarkers.NG-R holds a VHIR fellowship and MO-G a Joan Margarit VHIR fellowship. Research grants: from the Instituto de Salud Carlos III and European Regional Development Funds (PI16/00981, PI19/00186, RD16/0019/0021, and RD16/0019/0008), 2017-SGR-1427 program from the Generalitat de Catalunya-AGAUR, and Clinical Translational Program for Regenerative Medicine in Catalonia (P-CMR [C])