3,849 research outputs found
Sex-related differences in motor learning and performance
Gender differences have been shown across many domains, and motor skills are no exception. One of the most robust findings is a significant sex difference in throwing accuracy, which reflects the advantage of men in targeting abilities. However, little is known about the basis of this difference. To try to dissect possible mechanisms involved in this difference, here we tested for gender variations in a prism adaptation throwing task. We tested 154 subjects in a visuomotor prism adaptation task that discriminates between motor performance, visuomotor adaptation and negative aftereffects. Our results corroborate men's significant better throwing accuracy, although there were no adaptation differences between genders. In contrast, women showed significant larger negative aftereffects, which could be explained by a larger contribution of spatial alignment. These results suggest that different learning mechanisms, like strategic calibration and spatial alignment, may have different contributions in men and women
Promoting light hydrocarbons yield by catalytic hydrodechlorination of residual chloromethanes using palladium supported on zeolite catalysts
Gas catalytic hydrodechlorination (HDC) of trichloromethane (TCM) and dichloromethane (DCM) was analyzed using Pd (1 wt.%) on different zeolites as catalysts. The aim of this study was to know the surface properties of the catalysts and reaction conditions that promote the yield to light hydrocarbons in this reaction. Five different zeolite supports were used from three commercial zeolites (KL, L-type; NaY, Faujasite; H-MOR, Mordenite). KL and NaY were submitted to ionic exchange treatments in order to increase their acidity and analyze the effect of the acidity in the activity and selectivity of the HDC reaction. Exchanged zeolites (HL and HY) showed the highest Pd dispersion due to their higher surface acidity. The best TCM/DCM conversion and selectivity to light hydrocarbons was obtained using the two non-exchanged zeolite-catalysts, KL and NaY. Low surface acidity seems to be the key aspect to promote the formation of light hydrocarbons. The formation of these products is favored at high reaction temperatures and low H2: chloromethane ratios. KL showed the highest selectivity to olefins (60%), although with a lower dechlorination degree. Non-exchanged NaY catalyst showed high selectivity to paraffins (70% and 95% for the HDC of DCM and TCM, respectively)Authors gratefully acknowledge financial support from FEDER/Ministerio de Ciencia, Innovación y Universidades—Agencia Estatal de Investigación/ CTM2017-85498-R. C. Fernández Ruiz acknowledges MINECO for his research gran
Assessing the effectiveness of marine nature‐based solutions with climate risk assessments
Abstract
Prospective risks from climate change impacts in ocean and coastal systems are urging the implementation of nature‐based solutions (NBS). These are climate‐resilient strategies to maintain biodiversity and the delivery of ecosystem services, contributing to the adaptation of social‐ecological systems and the mitigation of climate‐related impacts. However, the effectiveness of measures like marine restoration or conservation is not exempt from the impacts of climate change, and the degree to which they can sustain biodiversity and ecosystem services remains unknown. Such uncertainty, together with the slow pace of implementation, causes decision‐makers and societies to demand a better understanding of NBS effects. To address this gap, in this study, we use the risk mitigation capacity of marine NBS as a proxy for their effectiveness while providing a toolset for the implementation of the method. The method considers environmental data and relies on expert elicitation, allowing us to go beyond current practice to evaluate the effectiveness of NBS in reducing habitat or species risks under different future socio‐political and climate‐change scenarios. As a result, we present a ready‐to‐use tool, and supporting materials, for the implementation of the Climate Risk Assessment method and an illustrative example considering the application of the NBS “nature‐inclusive harvesting” in two shellfisheries. The method works as a rapid assessment that guarantees comparability across sites and species due to its low data or resource demand, so it can be widely incorporated to adaptation policies across the marine realm.Agencia Estatal de Investigación | Ref. PID2021-127092OB-I00Universidade de Vigo/CISU
Acute-Stress Biomarkers in Three Octopodidae Species After Bottom Trawling
Several Octopodidae species have a great potential for the diversification of worldwide aquaculture. Unfortunately, the lack of stress-related biomarkers in this taxon results an obstacle for its maintenance in conditions where animal welfare is of paramount relevance. In this study, we made a first approach to uncover physiological responses related to fishing capture in Eledone moschata, Eledone cirrhosa, and Octopus vulgaris. Captured octopus from all three species were individually maintained in an aquaculture system onboard of oceanographic vessel in south-western waters of Europe. Haemolymph plasma and muscle were collected in animals at the moment of capture, and recovery was evaluated along a time-course of 48 h in Eledone spp., and 24 h for O. vulgaris. Survival rates of these species captured in spring and autumn were evaluated. Physiological parameters such as plasma pH, total CO2, peroxidase activity, lysozyme, hemocyanin, proteases, pro-phenoloxidase, anti-proteases, free amino acids, lactate and glucose levels, as well as muscle water percentage, free amino acids, lactate, glycogen and glucose values were analyzed. The immune system appears to be compromised in these species due to capture processes, while energy metabolites were mobilized to face the acute-stress situation, but recovery of all described parameters occurs within the first 24 h after capture. Moreover, this situation exerts hydric balance changes, as observed in the muscle water, being these responses depending on the species assessed. In conclusion, three Octopodidae species from south-western waters of Europe have been evaluated for stress-related biomarkers resulting in differentiated mechanisms between species. This study may pave the way to further study the physiology of stress in adult octopuses and develop new methodologies for their growth in aquaculture conditions
Caracterización y Simulación de un Diodo Schottky de Microondas
Presentado en el XXVIII Simposium Nacional de la Unión Científica Internacional de Radio. URSI 2013, Santiago de Compostela, 11 al 13 de septiembre de 2013.Microwave diode models included in commercial simulators use a large set of parameters, so they are often difficult to set up in order to match the actual response of a specific device. In this paper a simple model for a zero-bias microwave Schottky diode is presented. Noise characteristics are determined by measurements and then incorporated to the large signal model offered by the manufacturer in the diode datasheet. Using this model a diode power detector in large signal operation is simulated with commercial software, achieving excellent agreement with the measurement results, both in terms of power sensitivity and noise spectrum.Consejería de Economía, Innovación, Ciencia y Empleo de la Junta de Andalucía, mediante el proyecto P09-TIC-5268. Universidad de Málaga - Campus de Excelencia Internacional Andalucía Tec
Does Socioeconomic Status Influence the Risk of Subclinical Atherosclerosis?: A Mediation Model
BACKGROUND: Socioeconomic status (SES)-education, income level, and occupation-is associated with cardiovascular risk. OBJECTIVES: This study aimed to investigate the association between SES and subclinical atherosclerosis and the potential mechanisms involved. METHODS: SES, lifestyle habits (smoking, dietary patterns, physical activity, and hours of sleep), traditional risk factors, and subclinical atherosclerosis extent were prospectively assessed in 4,025 individuals aged 40 to 54 years without known cardiovascular disease enrolled in the PESA (Progression of Early Subclinical Atherosclerosis) study. After factors associated with atherosclerosis were identified, a multiple mediation model was created to quantify the effect of SES on subclinical atherosclerosis as explained by lifestyle behaviors. RESULTS: Although education level was significantly associated with the presence of atherosclerosis, no differences were found according to income level in this population. Participants with lower education presented with a higher risk of generalized atherosclerosis than those with higher education (odds ratio: 1.46; 95% confidence interval: 1.15 to 1.85; p = 0.002). Lifestyle behaviors associated with both education level and atherosclerosis extent were: smoking status, number of cigarettes/day, and dietary pattern, which explained 70.5% of the effect of SES on atherosclerosis. Of these, tobacco habit (smoking status 35% and number of cigarettes/day 32%) accounted for most of the explained differences between groups, whereas dietary pattern did not remain a significant mediator in the multiple mediation model. CONCLUSIONS: Despite the relative economic homogeneity of the cohort, lower education level is associated with increased subclinical atherosclerosis, mainly mediated by the higher and more frequent tobacco consumption. Smoking cessation programs are still needed, particularly in populations with lower education level.The PESA study is cofunded equally by the Fundación Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain; and Banco Santander, Madrid, Spain. The study also receives funding from the Institute of Health Carlos III (PI15/02019) and the European Regional Development Fund. The CNIC is supported by the Ministry of Economy, Industry and Competitiveness and the Pro CNIC Foundation, and is a Severo Ochoa Center of Excellence (SEV-2015-0505). This work is part of a project that has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No707642; and from the American Heart Association under grantnumber14SFRN20490315. Dr. Bueno has received research funding from the Instituto de Salud Carlos III (PIE16/00021), AstraZeneca, Bristol-Myers Squibb, Janssen, and Novartis; has received consulting fees from Abbott, AstraZeneca, Bayer, Bristol-Myers Squibb-Pfizer, and Novartis; and has received speaking fees or support for attending scientific meetings from AstraZeneca, Bayer, Bristol-Myers Squibb-Pfizer, Ferrer, Novartis, Servier, and MEDSCAPE-the heart.org.S
Aprendizaje de la programación guiado por los errores de compilación
Los errores de programación y en concreto los de
tiempo de compilación siempre han sido un área de
interés en el campo de la enseñanza de la
programación. Esto lo demuestran los distintos
artículos que aparecen periódicamente en congresos
de docencia de la informática, tanto nacionales como
internacionales. Estos estudios se basan en la relación
entre errores de programación y carencias
conceptuales o malas prácticas de programación, y
orientar a los docentes en las áreas y conceptos de
programación que se tendrían que reforzar en la
enseñanza de la programación. Sin embargo, estos
estudios se realizan siempre fuera del proceso de
aprendizaje de los estudiantes, con lo cual sólo se
extraen conclusiones generales para posteriores
cursos y sin poder proporcionar una realimentación
real e individualizada a los alumnos.
Hemos creado un sistema, denominado COLMENA
que se integra con el entorno de desarrollo integrado
para recopilar información sobre el análisis estático,
errores de compilación y warnings, que los
estudiantes generan durante un ejercicio de
programación. Además, esta información sobre
errores se visualiza a los usuarios clasificada por
familias de errores, sesiones de prácticas y alumnos.
Permitiendo al profesor realizar un seguimiento
completamente personalizado, para un grupo o un
alumno concreto. Por otra parte, facilita la
documentación de los distintos errores, estableciendo
una relación de estos con los conceptos de
programación y buenas prácticas relacionadas.
Además, permite a los alumnos darse cuenta de los
errores que cometen con más frecuencia y reforzar el
conocimiento de estos.
A través de esta herramienta, por tanto, se consigue
un flujo de intercambio de información que puede
ayudar a profesores y alumnos en la mejora del
proceso enseñanza-aprendizaje, y así perfeccionar
explícitamente detalles sobre pautas de programación
o conceptos relativos a la misma que antes no se
apreciaban o conocer la evolución de los errores de
un grupo a lo largo de una asignatura.SUMMARY -- Studies on errors in programming activities have
always been considered relevant among scientific
communities. Thus, different approaches are explored
every year in national and international conferences
about programming teaching and learning. All of
these studies deal with the relationship between
programming errors and bad habits in programming,
in order to generate guidance for teachers in concepts
where their students fail. However, these kinds of
studies are conducted outside the students' natural
programming process, which prevents teachers from
receiving a feedback report in real-time.
We have created an eclipse plug-in, called COLMENA,
whose purpose is to recover compilation
errors and warnings generated by the students during
programming lessons. Moreover, this information is
displayed in a specific portal where students can
retrieve information about the errors, their solutions
and different reports about individual and collective
information, such as specific groups or sessions
inside a subject. Students have the possibility to learn
about the solution to their most common errors in the
system or their top-10 error list.
Through COLMENA, we aim to assist teachers and
students with programming tips and ideas that generate
less errors and improve the teacher-learning
process. This kind of information, previously discarded,
allows us to gain a new perspective about the
problems that users have in a specific practical lesson
or in a whole subject
Human parietal reach region primarily encodes intrinsic visual direction, not extrinsic movement direction, in a visual motor dissociation task.
Posterior parietal cortex (PPC) participates in the planning of visuospatial behaviors, including reach movements, in gaze-centered coordinates. It is not known if these representations encode the visual goal in retinal coordinates, or the movement direction relative to gaze. Here, by dissociating the intrinsic retinal stimulus from the extrinsic direction of movement, we show that PPC employs a visual code. Using delayed pointing and event-related functional magnetic resonance imaging, we identified a cluster of PPC regions whose activity was topographically (contralaterally) related to the direction of the planned movement. We then switched the normal visual-motor spatial relationship by adapting subjects to optical left/right reversing prisms. With prisms, movement-related PPC topography reversed, remaining tied to the retinal image. Thus, remarkably, the PPC region in each hemisphere now responded more for planned ipsilateral pointing movements. Other non-PPC regions showed the opposite world- or motor-fixed pattern. These findings suggest that PPC primarily encodes not motor commands but movement goals in visual coordinates
Exergy as a measure of sustainable retrofitting of buildings
This study presents a novel optimization methodology for choosing optimal building retrofitting strategies based on the concept of exergy analysis. The study demonstrates that the building exergy analysis may open new opportunities in the design of an optimal retrofit solution despite being a theoretical approach based on the high performance of a Carnot reverse cycle. This exergy-based solution is different from the one selected through traditional efficient retrofits where minimizing energy consumption is the primary selection criteria. The new solution connects the building with the reference environment, which acts as “an unlimited sink or unlimited sources of energy”, and it adapts the building to maximize the intake of energy resources from the reference environment. The building hosting the School of Architecture at the University of Navarra has been chosen as the case study building. The unique architectural appearance and bespoke architectural characteristics of the building limit the choices of retrofitting solutions; therefore, retrofitting solutions on the façade, roof, roof skylight and windows are considered in multi-objective optimization using the jEPlus package. It is remarkable that different retrofitting solutions have been obtained for energy-driven and exergy-driven optimization, respectively. Considering the local contexts and all possible reference environments for the building, three “unlimited sinks or unlimited sources of energy” are selected for the case study building to explore exergy-driven optimization: the external air, the ground in the surrounding area and the nearby river. The evidence shows that no matter which reference environment is chosen, an identical envelope retrofitting solution has been obtaine
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