Edad y crecimiento de Barbus graellsii Steindachner, 1866 y Chondrostoma miegii, Steindachner, 1866 (Pisces, Cyprinidae) en el río Cinca (cuenca hidrográfica del Ebro, NE España)

The age and growth of two endemic cyprinids from the lberian peninsula were studied for one year in a stretch of the Cinca River. There were caught by electrofishing 279 individuals of B. graellsii and 189 individuals of Ch. miegii. lmmature specimens of both species were not caught probably due to their migratory behaviour during the reproductive period. B. graellsii presented a maximum of 11 age classes in both sexes. Female Ch. miegii live for 8 years and males seven years. Growth was allometric in B. graellsii specimens whereas Ch. miegii showed isometric growth. Females were longer than males in both species. B. graellsii females showed higher growth rates than males whereas Ch. miegii showed similar growth rates between sexes. B. graellsii males showed a significant increase in condition before the reproductive period and a decrease in condition during this period, while females only showed a significant decrease in condition in July. Ch. miegii females presented dynamics of condition very similar to B. graellsii males. Key words: Age, Growth, Cyprinidae, Barbus graellsii, Chondrostoma miegii.The age and growth of two endemic cyprinids from the lberian peninsula were studied for one year in a stretch of the Cinca River. There were caught by electrofishing 279 individuals of B. graellsii and 189 individuals of Ch. miegii. lmmature specimens of both species were not caught probably due to their migratory behaviour during the reproductive period. B. graellsii presented a maximum of 11 age classes in both sexes. Female Ch. miegii live for 8 years and males seven years. Growth was allometric in B. graellsii specimens whereas Ch. miegii showed isometric growth. Females were longer than males in both species. B. graellsii females showed higher growth rates than males whereas Ch. miegii showed similar growth rates between sexes. B. graellsii males showed a significant increase in condition before the reproductive period and a decrease in condition during this period, while females only showed a significant decrease in condition in July. Ch. miegii females presented dynamics of condition very similar to B. graellsii males. Key words: Age, Growth, Cyprinidae, Barbus graellsii, Chondrostoma miegii.The age and growth of two endemic cyprinids from the lberian peninsula were studied for one year in a stretch of the Cinca River. There were caught by electrofishing 279 individuals of B. graellsii and 189 individuals of Ch. miegii. lmmature specimens of both species were not caught probably due to their migratory behaviour during the reproductive period. B. graellsii presented a maximum of 11 age classes in both sexes. Female Ch. miegii live for 8 years and males seven years. Growth was allometric in B. graellsii specimens whereas Ch. miegii showed isometric growth. Females were longer than males in both species. B. graellsii females showed higher growth rates than males whereas Ch. miegii showed similar growth rates between sexes. B. graellsii males showed a significant increase in condition before the reproductive period and a decrease in condition during this period, while females only showed a significant decrease in condition in July. Ch. miegii females presented dynamics of condition very similar to B. graellsii males. Key words: Age, Growth, Cyprinidae, Barbus graellsii, Chondrostoma miegii

Edad, crecimiento y reproducción de Gobio gobio L. (Pisces, Cyprinidae) en un tramo regulado del río Segura (SE de España)

The age, growth and reproduction of Gobio gobio, were studied during a period of two years in a section of the Segura River regulated by the effect of a small upstream hydroelectric power station. A total of 254 specimens were caught monthly by electrofishing. The studied population showed a maximum of six age classes in females (0+–5+) and five in males (1+–5+). All females were mature at 2+ age class, whereas only 62.5% 2+ males showed mature gonads. During the studied period, both sexes showed maximum values of Gonadosomatic Index in May and spawn was different between the two studied periods. Compared with other populations, the studied population from a regulated locality is characterized by a non–seasonal body condition cycle and low captures of juvenile fish (0+, 1+) probably due to the effect of washing produced by drastic and unpredictable flow changes.La edad, crecimiento y reproducción de Gobio gobio, ha sido estudiada a lo largo de dos años en un tramo del río Segura regulado por una pequeña central hidroeléctrica. Mediante pesca eléctrica fueron capturados, mensualmente, un total de 254 ejemplares. Las hembras presentaron seis clases de edad (0+–5+) mientras que los machos presentaron cinco clases (1+–5+). Todas las hembras de clase de edad 2+ resultaron maduras mientras que los machos 2+ resultaron maduros en un 62,5% de los casos. Durante el periodo de estudio, ambos sexos presentaron los máximos valores del Índice Gonadosomático durante los meses de mayo aunque el desove resultó diferente entre los dos periodos estudiados. En comparación con otras poblaciones, la población estudiada en un tramo regulado del río se caracteriza por no presentar un ciclo estacional en la condición somática y bajas capturas de ejemplares juveniles (0+, 1+) debido, probablemente, al efecto de lavado provocado por los drásticos e impredecibles cambios en el caudal

Response of C(60) and C(n) to ultrashort laser pulses

Journals published by the American Physical Society can be found at http://journals.aps.org/In this paper we introduce a method for realistic simulations of nonadiabatic processes, including the interaction of light with matter. Calculations of the response Of C(60) and carbon chains to laser pulses demonstrate that even rather subtle features are correctly described. For example, in C(60) the pentagonal-pinch models dominant at low fluence, the breathing mode is dominant at high fluence, and dimers are preferentially emitted during photofragmentation. In carbon chains, on the other hand, trimers tend to be broken off. After collisional fragmentation, the remnants of a C(60) molecule tend to reform their bonds, yielding new 5, 6, or 7 membered rings

Rule reactivation and capture errors in goal directed behaviour

In everyday life people may act automatically, following "unwanted" lines of action which are triggered by contextual cues and may interfere with current goals. Such occurrences are known as "capture errors" in reference to errors that occur when a more salient behaviour takes place when a similar, but less salient, action was intended. Clinical neuropsychological studies suggest that reactivation of previous rules may play an important role in behavioural interference, but such reactivation has been little studied in normal subjects and simple experimental tasks. In the present study we develop this theme, presenting data on 4 subjects who spontaneously showed capture errors in verbal fluency tasks, and developing a new experimental paradigm specifically designed to elicit such interference in normal subjects. In the new paradigm, 101 normal subjects performed a simple series of working memory tasks, including occasional stimuli whose answer matched both the current and the previous rule. We found that normal controls indeed tend to commit more mistakes after the presentation of a stimulus whose answer is consistent with a current and preceding rule. In this case, however, the errors produced are not necessarily associated with a shift back to the old rule, suggesting that rule reactivation leads to a more general interference effect. We discuss the importance of our data from both theoretical and clinical perspectives

Amphibians in the Region of Murcia (SE Iberian peninsula): conservation status and priority areas

The conservation status of amphibian species was studied in the Region of Murcia, taking into consideration 10 variables concerning their biology and distribution. The results obtained show that the amphibian species exposed to the highest risk of extinction in the study area are those with long larval development and a restricted distribution range. According to this species classification, an index is proposed for assessing areas whose conservation is of the highest priority. In the Region of Murcia, most of these areas are located in the main mountain systems, primarily confined to the northwest. Regional Parks and proposed priority conservation areas overlap by only about 12%. The current isolation of these areas makes it necessary to undertake habitat restoration programmes to ensure their interconnection

Molecular dynamics study of the fragmentation of silicon doped fullerenes

Tight binding molecular dynamics simulations, with a non orthogonal basis set, are performed to study the fragmentation of carbon fullerenes doped with up to six silicon atoms. Both substitutional and adsorbed cases are considered. The fragmentation process is simulated starting from the equilibrium configuration in each case and imposing a high initial temperature to the atoms. Kinetic energy quickly converts into potential energy, so that the system oscillates for some picoseconds and eventually breaks up. The most probable first event for substituted fullerenes is the ejection of a C2 molecule, another very frequent event being that one Si atom goes to an adsorbed position. Adsorbed Si clusters tend to desorb as a whole when they have four or more atoms, while the smaller ones tend to dissociate and sometimes interchange positions with the C atoms. These results are compared with experimental information from mass abundance spectroscopy and the products of photofragmentation.Comment: Seven two-column pages, six postscript figures. To be published in Physical Review

The first occurrence of Cobitis paludica (de Buen, 1930) in the Segura River Basin (SE Iberian Peninsula)

The aim of the present report is to describe the establishment of viable populations of Cobitis paludica (de Buen, 1930) in the Segura River Basin. We found two isolated populations: one located in the upper part of the Segura River and the mouth of its tributary, the Zumeta River, and another in the Mundo River, between the Talave and Camarillas reservoirs. We hypothesised that the introduction of this species may be attributable to the deliberate or accidental introduction by anglers or fish translocation from the Tajo-Segura interbasin water transfer system. C. paludica is a threatened endemic fish species from the Iberian Peninsula, and it exhibits sharply declining populations. Therefore, further investigation is needed to assess the genetic origin of the populations reported in this report and to monitor the population trends to determine the population status and the appropriate management plan in the Segura River Basin.El presente trabajo constituye la primera referencia al establecimiento de poblaciones viables de Cobitis paludica (de Buen, 1930) en la cuenca del río Segura. Se han detectado dos poblaciones separadas geográficamente: una localizada en la zona alta del río Segura y la desembocadura del río Zumeta, y otra en el río Mundo, entre los embalses de Talave y Camarillas. Su presencia puede ser debida a la introducción deliberada o accidental por parte de los pescadores, o a la translocación de ejemplares a través del trasvase Tajo-Segura. C. paludica es una especie amenazada endémica de la Península Ibérica cuyas poblaciones se encuentran actualmente en declive. En este sentido, es necesario realizar estudios genéticos que confirmen el origen de estas poblaciones y desarrollar protocolos de seguimiento para establecer su estado poblacional y el plan de gestión de esta especie en la cuenca del río Segura

Variability in population traits of a sentinel iberian fish in a highly modified mediterranean-type river

Human pressures on water resources have been suggested as a driver of biological traits that induce changes in native fish populations. This study highlighted the interplay between environmental stress factors, mostly related to flow regulation, and the longitudinal river gradient in biological traits such as the growth, size structure and somatic condition of a sentinel fish, Luciobarbus sclateri. We found an increase in size-related metrics and somatic condition at population levels associated with downstream reaches, although fragmentation and habitat alteration, flow regime alteration and the abundance of non-native fish were also significantly involved in their variability. Age-related parameters and growth were only explained by flow regime alterations and the abundance of non-native fish species. The high plasticity observed in L. sclateri population traits suggests that this is a key factor in the species adaptability to resist in a strongly altered Mediterranean river basin. However, the interplay of multiple stressors plays an important role in fish population dynamics and could induce complex responses that may be essential for long-term monitoring in sentinel species

INVENTARIO FAUNÍSTICO DE LOS QUIRONÓMIDOS (DIPTERA, CHIRONOMIDAE) DE EL RÍO MUNDO (ALBACETE). ESPAÑA

For each season of one year, a drift data sample was taken from a single locality of the Mundo River (Segura Basin, Albacete province). 43 chironomid species were identified. All species are new for Albacete province and two species (Orthocladius pedestris and Virgatanytarsus albisutus) are new for Spain.Por primera vez se presenta un listado de 43 especies de quironómidos para el Río Mundo (Cuenca del Río Segura en Albacete) obtenido a partir de muestras de deriva tomadas en las cuatro estaciones del año. Las 43 especies de quironómidos citadas son nuevas para esta provincia y dos de ellas (Orthocladius pedestris y Virgatanytarsus albisutus) son nuevas citas para España