El Efecto de la Edad Relativa (RAE) en el fútbol profesional español masculino y femenino: temporada 2016 – 2017.

El efecto de la edad relativa (Relative Age Effect, RAE) ha sido, y sigue siendo, motivo de estudio desde hace muchos años, afectando tanto al ámbito educativo como al deportivo, en el que intervienen aspectos de carácter económico, social y psicológico entre otros, que pueden ser decisivos a la hora del desarrollo y maduración del individuo. El objetivo del presente estudio es comprobar si se produce un efecto de la edad relativa en la Liga de Fútbol Profesional española (LFP), tanto en la primera división masculina (Liga Santander) como en la primera división femenina (Liga Iberdrola), teniendo en cuenta que el corte de edad actual para la formación de las categorías es el del año natural. El análisis ha incluido a todos los futbolistas de la primera división española masculina de la temporada 2016-2017, con un total de 484 jugadores distribuidos entre los 20 equipos que conforman la Liga Santander, así como a todas las futbolistas de la primera división española femenina de la temporada 2016-2017, siendo un total de 361 jugadoras distribuidas en 16 equipos, que son los que conforman la Liga Iberdrola. El resultado del estudio confirma un importante efecto de la edad relativa en el fútbol profesional en España, siendo mayor en la liga masculina, donde el 61,98% de los futbolistas han nacido en el primer semestre del año, mientras que en la liga femenina disminuye, aunque se mantiene por encima de la mitad, siendo el 53,74% de las futbolistas las que nacieron en el primer semestre del año. Además se ha realizado el estudio del efecto de la edad relativa llevando a cabo una diferenciación por nacionalidad y posición en el terreno de juego de ambas competiciones, de los cuales se han obtenido resultados muy significativos.pre-print1119 K

Agrupaciones demersales y bentónicas de los fondos arrastrables del mar de alborán (mediterráneo occidental)

The composition and abundance of megabenthic fauna caught by the commercial trawl fleet in the Alboran Sea were studied. A total of 28 hauls were carried out at depths ranging from 50 to 640 m. As a result of a hierarchical classification analysis four assemblages were detected: (1) the outer shelf group (50-150 m), characterised by Octopus vulgaris and Cepola macrophthalma; (2) the upper slope group (151-350 m), characterised by Micromesistius poutassou, with Plesionika heterocarpus and Parapenaeus longirostris as secondary species; (3) the middle slope group (351-640 m), characterised by M. poutassou, Nephrops norvegicus and Caelorhincus caelorhincus, and (4) the small seamount Seco de los Olivos (310-360 m), characterised by M. poutassou, Helicolenus dactylopterus and Gadiculus argenteus, together with Chlorophthalmus agassizi, Stichopus regalis and Palinurus mauritanicus. The results also revealed significantly higher abundances in the Seco de los Olivos seamount, probably related to a higher food availability caused by strong localised currents and upwellings that enhanced primary production. Although depth proved to be the main structuring factor, others such as sediment type and food availability also appeared to be important. Differences between shelf and slope assemblages could be in part related to a greater dependence on benthic resources in the former and a higher use of planktonic resources in the latter.Se estudia la composición y abundancia de la fauna capturada por barcos comerciales de arrastre en el mar de Alborán. Se llevaron a cabo 28 lances a profundidades comprendidas entre los 50 y los 640 m. El análisis de clasificación jerárquica dio como resultado cuatro agrupaciones: (1) plataforma externa (50-150 m) caracterizada por las especies Octopus vulgaris y Cepola macrophthalma, (2) talud superior (151-350 m), caracterizada por Micromesistius poutassou, con Plesionika heterocarpus y Parapenaeus longirostris como especies secundarias, (3) talud medio (351-640 m) caracterizada por M. poutassou, Nephrops norvegicus y Caelorhincus caelorhincus, y (4) el monte submarino Seco de los Olivos (310- 360 m), donde M. poutassou, Helicolenus dactylopterus y Gadiculus argenteus son las especies más características, junto a otras como Chlorophthalmus agassizii, Stichopus regalis y Palinurus mauritanicus. Los resultados revelan una abundancia de megafauna significativamente mayor en Seco de los Olivos, probablemente relacionada con una mayor disponibilidad de alimento provocada por las fuertes corrientes y afloramientos que tienen lugar en la zona, y que generan un aumento en la producción primaria. Aunque la profundidad constituye el principal factor estructurante de las comunidades, también son importantes el tipo de sedimento y la disponibilidad de alimento. Las diferencias encontradas entre las comunidades de plataforma y de talud podrían estar en parte relacionadas con una mayor dependencia de los recursos bentónicos en la primera, y un mayor aprovechamiento de los recursos planctónicos en la segunda.

Bythocaris cosmetops (Decapoda: Caridea: Hippolytidae) in the western Mediterranean Sea

The capture of the species Bythocaris cosmetops in the Alboran Sea (southern Spain, western Mediterranean Sea), previously known from only two specimens from the Atlantic, Sierra Leone (south-west Africa) and the northern Bay of Biscay (north-west Europe), represents the first record of the genus and species in the Mediterranean Sea and Iberian Peninsula (south-west Europe). New data on morphology, biology and habitat are provided and discussed.Postprint0,000

Damage assessment and survival estimates in the wedge clam (Donax trunculus) caught by mechanical dredging in the northern Alboran Sea

This paper describes the impact of dredging on populations of the wedge clam (Donax trunculus) at two sites along the northern Alboran coast. Damage was assessed by quantifying shell and foot damage on commercial clams caught with mechanical dredges. Survival experiments were carried out to assess their survival capacity after 24 h purification treatment and 72 h cold storage, which represents an issue of great interest for fisheries research, management and marketing. Overall, 2.4% of wedge clams suffered any type of damage, including chipped edges and scratched valves. Higher proportions of shell-damaged individuals were positively correlated to bottom features (e.g. gravel content in sediment). Moreover, higher towing speed significantly increased shell damage. Analyses of shell damage areas revealed that the anterior dorsal and ventral parts of the shell are the most vulnerable to dredging. A total of 15.9% of individuals showed damage on the foot, which seems not to affect their survival. The incidence of foot damage was mostly linked to sublethal predation, reflected in a positive correlation between the proportion of foot-damaged individuals and biomass of decapod crustaceans in the fishing ground. Finally, D. trunculus exhibited very low mortality rates after 24 h purification treatment (0.2–0.4%) and 72 h cold storage (0.3–3.2%). The survival rate at the end of the experiment was high (>96%), with the highest mortality observed 96 h after the fishing day. No correlations were found between mortality rates and bottom type or towing speed.Postprin

First substantiated record of Raja asterias Delaroche, 1809 (Elasmobranchii: Rajiformes: Rajidae) in the Gulf of Cádiz, North-eastern Atlantic

The Mediterranean starry ray, Raja asterias, considered endemic in the Mediterranean, has recently been reported by other authors from Atlantic fisheries in southern Portugal and northern Morocco. There has been, however, no substantiated record of the species outside the Mediterranean. This fact and the easiness of confusion of R. asterias with other species have probably prevented those records from being taken into account in the recent catalogue of North Atlantic elasmobranchs species, in the assessment of the population status of this species, and in recent annotated global checklists of chondrichthyans. In our study, a specimen of R. asterias was collected from the Gulf of Cádiz and its species identity was assessed based on morphological and molecular methods. The presently reported finding constitutes a substantiated record of R. asterias from the Atlantic. Based on this record, previously reported catches of the Mediterranean starry ray in the Atlantic should be confirmed, and if so, these populations should be included in future assessments of this vulnerable species and in the description of its geographic distributionVersión del editor0,54

The evaluation of surface diffusion coefficients of gold and platinum atoms at electrochemical interfaces from combined STM-SEM imaging and electrochemical techniques

A simple method is presented for measuring the surface diffusion coefficients of Au and Pt atoms at electrodispersed electrodes of the same metals in contact with 0.5M H2SO4. The technique is based upon the time dependence of the surface roughness factor of electrodispersed metal overlayers. The method requires a model for the surface roughness of the metal structure. The model is deduced from microscopic measurements by a STM integrated into a conventional SEM microscope. This allows the relationship between the roughness factor and the area of the surface structure to be obtained. For Au and Pt in contact with an electrolyte solution, the values of our diffusion coefficients are higher than those reported in vacuum at the same temperature.Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas (INIFTA)Facultad de Ciencias Exacta

An approach to the spatial distribution of fishing effort in the Gulf of Cadiz.

The spatial distribution of the fishing effort exerted by the trawl fleet of Isla Cristina port (Huelva, Spain) is simulated by means of an application (FAST) for Geographic Information Systems (ArcView), which can offer results just with limited input data. The simulation were carried out with three input variables: depth, distance from fishing grounds to port and the fishing laws in force in the area. The results obtained from two simulations tested match up the effort distribution detected in the area for both the fleet as a whole and a given segment of the same.Postprin

INFORME CAMPAÑA ARSA 1115

Durante los días de 30 de octubre al 12 de noviembre del 2015 se ha llevado a cabo la campaña con arte de arrastre de fondo ARSA-1115. La zona prospectada ha correspondido a la zona de plataforma y talud continental de la parte española del Golfo de Cádiz, comprendida entre el meridiano 7º 20’ W, o la frontera con Portugal, el paralelo 36º 15’ N, entre las isóbatas de 15 y 800 m, siendo su límite inferior la distancia de 6 millas a la costa. La campaña se realizó a bordo del B/O "Miguel Oliver", siendo el objetivo previsto la estimación de los índices de abundancia (número y biomasa), de las especies demersales de mayor interés pesquero, así como de la fauna asociada a ellas