Analysis of the influence of the líbero in different phases of game in volleyball

El objetivo del estudio fue analizar la participación y la influencia del jugador líbero en la fase de ataque y en la fase de defensa en voleibol masculino de alto nivel. La muestra de estudio estuvo compuesta por 1101 acciones de juego de recepción y defensa, de los cuatro equipos masculinos mejor clasificados en los JJOO de Pekin 2008. Las variables consideradas en el estudio fueron: clasificación del equipo, jugador receptor/defensa, zona de recepción/defensa, eficacia de recepción/defensa, eficacia de la colocación, zona de ataque/contraataque, tiempo de ataque/contraataque, eficacia de ataque/contraataque. La medida de dichas variables se realizó mediante la observación sistemática, indirecta y externa. Se recurrió a la estadística descriptiva y, posteriormente, se utilizaron técnicas de estadística inferencial, basada en tablas de contingencia, valores de Chi-cuadrado y V de Cramer. Los resultados mostraron que, en la fase de defensa, hubo asociaciones significativas entre: el jugador que defiende y la zona de defensa, predominando la defensa del líbero en zona 5; el jugador que defiende y la eficacia de la defensa, siendo mejorada por parte del líbero; el jugador que defiende y la zona de contraataque, incrementándose los ataques por zona 6 cuando defiende el líberoThe aim of the study was to analyse the libero’s participation and their influence in the attack and defence phases in men's elite volleyball. The sample of this study was composed by 1101 pass and defence game actions of the four highest-placed teams in the 2008 Beijing Olympic Games. The study’s variables include team classification, receiving/defending player, pass/defence zone, pass/defence effectiveness, setting effectiveness, attack/counterattack zone, attack/counterattack time, and attack/counterattack effectiveness. These variables were measured by both indirect and external systematic observation. A descriptive statistical study was used, followed by inferential statistical techniques based on contingency tables, Chi-square tests, and Cramer's V values. The results revealed that there were significant associations during the defensive stage of the game between the defending player and the defensive phase, the libero’s defence predominating in zone 5; the defending player and defence efficiency, which is improved by the libero; the defending player and counterattack, as attacks increased in zone 6 when the libero was defendin

Realtime local navigation for the blind: detection of lateral doors and sound interface

Worldwide there are about 285 million visually impaired persons, of which 39 million are blind and the others have low vision. Almost all systems designed to assist them are quite complex and expensive, but most blind persons do not have advanced technical assistance and they are rather poor. We are therefore developing a low-cost navigation aid which can be afforded by almost all blind persons: basically, the ultimate goal is to use only a mobile phone with a built-in camera. This aid complements the white cane, it is easily portable, and it is not a hindrance when walking with the cane. The system will have an easy and intuitive interface, yet providing assistance in local and global navigation in realtime. In this paper we present the progress concerning local navigation. Path and obstacle detection just beyond the reach of the cane is now supplemented by detection of doors in corridors. This is necessary for localization, i.e., for developing a better impression of the environment and for finding a specific room. A sophisticated sound interface can assist the user for centering on paths like sidewalks and corridors, alerting to looming obstacles for avoiding them

Adaptation and convergence in circadian‐related genes in Iberian freshwater fish

The circadian clock is a biological timing system that improves the ability of organisms to deal with environmental fluctuations. At the molecular level it consists of a network of transcription-translation feedback loops, involving genes that activate (bmal and clock - positive loop) and repress expression (cryptochrome (cry) and period (per) - negative loop). This is regulated by daily alternations of light but can also be affected by temperature. Fish, as ectothermic, depend on the environmental temperature and thus are good models to study its integration within the circadian system. Here, we studied the molecular evolution of circadian genes in four Squalius freshwater fish species, distributed across Western Iberian rivers affected by two climatic types with different environmental conditions (e.g., light and temperature). S. carolitertii and S. pyrenaicus inhabit the colder northern region under Atlantic climate type, while S. torgalensis, S. aradensis and some populations of S. pyrenaicus inhabit the warmer southern region affected by summer droughts, under Mediterranean climate type.info:eu-repo/semantics/publishedVersio

Blavigator: a navigation aid for blind persons

Blavigator (blind navigator) is a vision aid for blind and visuaIIy impaired persons. It supports local navigation by detecting waIkable paths in the immediate vicinity of the user. It guides the user for centering on the path

Analysis of the equilibrium distribution of Ligands in Heterogeneous Media – Approaches and pitfalls

The equilibrium distribution of small molecules (ligands) between binding agents in heterogeneous media is an important property that determines their activity. Heterogeneous systems containing proteins and lipid membranes are particularly relevant due to their prevalence in biological systems, and their importance to ligand distribution, which, in turn, is crucial to ligand’s availability and biological activity. In this work, we review several approaches and formalisms for the analysis of the equilibrium distribution of ligands in the presence of proteins, lipid membranes, or both. Special attention is given to common pitfalls in the analysis, with the establishment of the validity limits for the distinct approaches. Due to its widespread use, special attention is given to the characterization of ligand binding through the analysis of Stern–Volmer plots of protein fluorescence quenching. Systems of increasing complexity are considered, from proteins with single to multiple binding sites, from ligands interacting with proteins only to biomembranes containing lipid bilayers and membrane proteins. A new formalism is proposed, in which ligand binding is treated as a partition process, while considering the saturation of protein binding sites. This formalism is particularly useful for the characterization of interaction with membrane proteins.info:eu-repo/semantics/publishedVersio

Analysis of the Equilibrium Distribution of Ligands in Heterogeneous Media–Approaches and Pitfalls

The equilibrium distribution of small molecules (ligands) between binding agents in heterogeneous media is an important property that determines their activity. Heterogeneous systems containing proteins and lipid membranes are particularly relevant due to their prevalence in biological systems, and their importance to ligand distribution, which, in turn, is crucial to ligand’s availability and biological activity. In this work, we review several approaches and formalisms for the analysis of the equilibrium distribution of ligands in the presence of proteins, lipid membranes, or both. Special attention is given to common pitfalls in the analysis, with the establishment of the validity limits for the distinct approaches. Due to its widespread use, special attention is given to the characterization of ligand binding through the analysis of Stern–Volmer plots of protein fluorescence quenching. Systems of increasing complexity are considered, from proteins with single to multiple binding sites, from ligands interacting with proteins only to biomembranes containing lipid bilayers and membrane proteins. A new formalism is proposed, in which ligand binding is treated as a partition process, while considering the saturation of protein binding sites. This formalism is particularly useful for the characterization of interaction with membrane proteins

Transforming ideas and developing entrepreneurship skills in computing sciences and informatics engineering courses

This paper presents an approach on entrepreneurship education which helps to turn ideas into Minimum Viable Products (MVP) and to capacitate students to become entrepreneurs. In this approach, we integrate development and management project to different business models. Students acquire, in addition to technical competencies, skills on market knowledge and business modeling. This approach has been applied for several years in an informatics engineering course and suggests a set of activities on 18 weeks. Teachers’ perceptions and students’ opinions were collected through direct observations and using a questionnaire in order to evaluate the process behind this pedagogical project which goes beyond the walls of the university. Most of the students are satisfied with the process since they develop projects that have a good fit with the market needs and opportunities and some of them are close to creating a startup.(undefined

Wearable inertial sensor system towards daily human kinematic gait analysis: benchmarking analysis to MVN BIOMECH

This paper presents a cost- and time-effective wearable inertial sensor system, the InertialLAB. It includes gyroscopes and accelerometers for the real-time monitoring of 3D-angular velocity and 3D-acceleration of up to six lower limbs and trunk segment and sagittal joint angle up to six joints. InertialLAB followed an open architecture with a low computational load to be executed by wearable processing units up to 200 Hz for fostering kinematic gait data to third-party systems, advancing similar commercial systems. For joint angle estimation, we developed a trigonometric method based on the segments’ orientation previously computed by fusion-based methods. The validation covered healthy gait patterns in varying speed and terrain (flat, ramp, and stairs) and including turns, extending the experiments approached in the literature. The benchmarking analysis to MVN BIOMECH reported that InertialLAB provides more reliable measures in stairs than in flat terrain and ramp. The joint angle time-series of InertialLAB showed good waveform similarity (>0.898) with MVN BIOMECH, resulting in high reliability and excellent validity. User-independent neural network regression models successfully minimized the drift errors observed in InertialLAB’s joint angles (NRMSE < 0.092). Further, users ranked InertialLAB as good in terms of usability. InertialLAB shows promise for daily kinematic gait analysis and real-time kinematic feedback for wearable third-party systems.This work has been supported in part by the Fundação para a Ciência e Tecnologia (FCT) with the Reference Scholarship under Grant SFRH/BD/108309/2015 and SFRH/BD/147878/2019, by the FEDER Funds through the Programa Operacional Regional do Norte and national funds from FCT with the project SmartOs under Grant NORTE-01-0145-FEDER-030386, and through the COMPETE 2020—Programa Operacional Competitividade e Internacionalização (POCI)—with the Reference Project under Grant POCI-01-0145-FEDER-006941

Behaviour of NBD-head group labelled phosphatidylethanolamines in POPC bilayers: a molecular dynamics study

A complete homologous series of fluorescent phosphatidylethanolamines (diCnPE), labelled at the head group with a 7-nitrobenz-2-oxa-1,3-diazo-4-yl(NBD) fluorophore and inserted in 1-palmitoyl, 2-oleoyl-snglycero- 3-phosphocholine (POPC) bilayers, was studied using atomistic molecular dynamics simulations. The longer-chained derivatives of NBD-diCnPE, with n = 14, 16, and 18, are commercially available, and widely used as fluorescent membrane probes. Properties such as location of atomic groups and acyl chain order parameters of both POPC and NBD-diCnPE, fluorophore orientation and hydrogen bonding, membrane electrostatic potential and lateral diffusion were calculated for all derivatives in the series. Most of these probes induce local disordering of POPC acyl chains, which is on the whole counterbalanced by ordering resulting from binding of sodium ions to lipid carbonyl/glycerol oxygen atoms. An exception is found for NBD-diC16PE, which displays optimal matching with POPC acyl chain length and induces a slight local ordering of phospholipid acyl chains. Compared to previously studied fatty amines, acyl chain-labelled phosphatidylcholines, and sterols bearing the same fluorescent tag, the chromophore in NBD-diCnPE locates in a similar region of the membrane (near the glycerol backbone/carbonyl region) but adopts a different orientation (with the NO2 group facing the interior of the bilayer). This modification leads to an inverted orientation of the P–N axis in the labelled lipid, which affects the interface properties, such as the membrane electrostatic potential and hydrogen bonding to lipid head group atoms. The implications of this study for the interpretation of the photophysical properties of NBD-diCnPE (complex fluorescence emission kinetics, differences with other NBD lipid probes) are discussed

Different Citrus rootstocks present high dissimilarities in their antioxidant activity and vitamins content according to the ripening stage

“Lane Late” sweet orange grafted on six different citrus rootstocks and grown in the Guadalquivir valley (Seville, Spain) were picked at different ripening stages in two consecutive seasons to characterize their antioxidant activity (free radicals scavenging activity, reducing power and lipid peroxidation inhibition) and quantify their main antioxidant compounds (vitamin E and vitamin C). Linear discriminant analysis and 2-way ANOVA were applied to compare the effects induced by citrus rootstock and ripening stage. The results showed that differences in antioxidant activity and related compounds are mainly dependent on the citrus rootstock, despite ripening stage had also some particular effects. Changes observed in 2012 showed less marked differences among the citrus rootstock. Nevertheless, Cleopatra rootstock showed the highest antioxidant activity in both years, indicating that an increase in its cultivation might be a good solution to sweet orange farmers. Concerning the ripening stage, samples collected in January presented higher vitamin contents, while those collected in April showed higher antioxidant activity. This result allows deciding the harvesting period according to the desired effect.Foundation for Science and Technology (FCT, Portugal) for financial support to the research center CIMO (strategic project PEst-OE/AGR/UI0690/2011), J.C.M. Barreira grant (SFRH/BPD/72802/2010) and L. Barros researcher contract under “Programa Compromisso com Ciência - 2008”. And Vanessa Cardeñosa is grateful to IFAPA for the fellowship obtained for the development of her PhD thesis