Sexual Dimorphism in Rissoides Pallidus (Giesbrecht) (Crustacea, Stomatopoda)

EnThirteen morphometric characters of Rissoides pallidus (Giesbrecht), a small stomatopod crustacean, were measured from 34 males and 32 females. The specimens were collected by means of bottom trawlers on the upper continental slope of the North Tyrrhenian Sea (mid-western Mediterranean Sea). Comparisons of the slopes between sexes indicated no significant difference in all studied dependent parameters (Y) with carapace length (X), except antennular length and scaphocerite width which were significantly longer and larger in females than in males, respectively. The hierarchical cluster analysis was also performed to identify similarity or dissimilarity among the morphometric characters measured. The biometric relationships considered in this work may prove useful during studies of feeding habits, and to reconstruct the size and biomass of the individuals of this small mantis shrimp from the remains of its exoskeleton.ItTredici caratteri morfometrici sono stati misurati in 34 maschi e 32 femmine di Rissoides pallidus (Giesbrecht), un piccolo crostaceo stomatopode. Gli esemplari sono stati raccolti per mezzo di motopescherecci che operano sulla scarpata continentale superiore del Mar Tirreno settentrionale (Mediterraneo occidentale). La comparazione del parametro b delle regressioni nei due sessi non ha mostrato alcuna differenza significativa tra tutti i parametri indagati, ad esclusione della lunghezza delle antennule e della larghezza dello scafocerite che rispettivamente sono risultati significativamente più lunghe e più larghe nelle femmine che nei maschi. È stata eseguita anche un’analisi di agglomerazione al fine di identificare similarità o dissimilarità tra i caratteri morfometrici utilizzati. Le relazioni biometriche considerate in questo lavoro possono risultare utili negli studi di alimentazione poiché dai resti degli individui di questo piccolo stomatopode è possibile risalire alla loro taglia e relativa biomassa

room and window geometry influence for daylight harvesting maximization effects on energy savings in an academic classroom

Abstract Lighting systems have a fundamental role for the overall buildings energy consumption. Therefore, remarkable efforts are required for optimizing the lighting systems energy use and for finding new daylight harvesting solutions. In this paper, the impacts on daylight harvesting provided by different room and window geometries and their effects on energy savings are presented. An academic classroom with only one window is chosen as case study and it is supposed that the window orientation is modified according to the four cardinal points. A climate-based approach was chosen for the multiple simulations, carried out via DIVA software, by assuming: square and rectangular classroom geometries with the same total area; square and rectangular window shapes having Window to Floor Ratios (WFRs) equal to 8% and 12%; two different dimmable lighting systems, in order to quantify the energy savings, by considering fluorescent and LED dimmable lamps. The daylight analysis, performed by evaluating both the Daylight Factor (DF) and the Daylight Autonomy (DA), showed that room and window geometries have high influence on daylight harvesting maximization, allowing remarkable energy savings (up to 48.5%) with respect to non-dimmable lighting system. In particular, the best energy result, equal to 467.5 kWh/yr, was obtained with rectangular room and window geometries coupled with LED lamps and WFR equal to 12%

Struktura dna, veličina čestica sedimenta i makrobentoska zajednica u eksploatiranim i ne-eksploatiranim područjima srednjeg Jadrana (Italija)

Studies performed in Italy for assessing the effects of fishing activities have been largely confined to the Adriatic Sea. They mostly investigated effects of experimentally induced impacts. The objective of this study was to compare a commercial fishing ground with an area in which no fishing was conducted. The two areas were less than 2 km apart and close to a gas platform in the central Adriatic. Seabed morphology, sediment grain size, and macrobenthic community composition were investigated. There were clear physical effects on the seabed morphology, mostly as a consequence of the trawling passage. Strong and unequivocal signs of disturbance were not detected from the grain size analysis but there was a major spatial variability of sediment distribution. There were signs of stress in the macrobenthic community, i.e., reduction of complexity and diversity, increased variability of distributional patterns, and fewer large longlived species in the fished area.Talijanske studije za utvrđivanje utjecaja ribolovnih aktivnosti bile su uglavnom usmjerene na Jadransko more istražujući učinke pretežito tijekom eksperimentalnih potega. Cilj ove studije je usporedba područja izložena gospodarskom ribolovu i područja koja se gospodarski ne iskorištavaju. Dva istraživana područja su smještena 2 km od plinske platforme u srednjem Jadranu. Istraživani su: struktura morskog dna, veličina i struktura sedimenta, te makrobentoske zajednice. Jasno je uočljiv fizički učinak na strukturu morskog dna, uglavnom kao posljedica prolaska koća. Nisu utvrđeni jaki i jasni znakovi poremećaja u veličini čestica sedimenta, ali je utvrđena značajna prostorna varijabilnost u distribuciji sedimenta. U eksploatiranom području nađeni su znakovi stresa u makrobentoskoj zajednici tj. poremećaj u kompleksnosti i raznolikosti, povećane varijabilnosti u raspostranjenosti i manji broj velikih i dugoživućih vrsta

Trayectoria a largo plazo de algunas especies de Elasmobranquios en los mares de Toscana (Mediterráneo noroccidental) a través de 50 años de datos de captura

The time series of elasmobranch catch rates off the Tuscany coasts (NW Mediterranean) were investigated by means of min/max auto-correlation factor analysis in order to estimate variations in population abundance and evaluate the influence of environmental and anthropogenic factors. The analyses highlighted a general decreasing trend in the catch rates of sharks and skates from 1961 to the mid-1990s, mainly influenced by the increase in fishing effort. Since the 1990s, the EU Common Fishery Policy for the Mediterranean has promoted the reduction of fishing fleets through incentives to vessel demolition. The Porto S. Stefano trawl fleet has decreased by about 50%, leading to a decrease in fishing effort which seemed to be the most relevant factor affecting the increasing trend shown by the catch rates of Galeus melastomus, Scyliorhinus canicula and skates from 1991 to 2009. The elasmobranch assemblage did not undergo major shifts but the weighted frequency of occurrence shows that elasmobranchs were more frequent in the past. Particular caution should be paid in interpreting the recent rebound of some species as an early sign of recovery: trawl survey data and landing data show that over the last 50 years elasmobranch fauna have undergone a drastic decline and that recent rebounds are still far from a recovery to historical levels.Se investigaron las series históricas de datos de captura de algunas especies de Elasmobranquios en los mares de Toscana (Mediterráneo noroccidental), por medio del análisis de auto-correlación factorial MAFA, con el fin de evaluar las variaciones en la abundancia de poblaciones y la influencia de factores ambientales y antropogénicos. Los análisis permitieron poner en relieve una tendencia a la disminución, a partir de 1961 hasta la mitad de los años 1990, de las tasas de captura de las especies de tiburones y rayas demersales. Esta disminución parece ser debida principalmente al aumento del esfuerzo pesquero. Sin embargo, desde 1990 capacidad y actividad pesquera mostraron una tendencia a la disminución, como resultado de la Política Pesquera Común de la UE para el Mediterráneo. La flota de arrastre de Porto Santo Stefano disminuyó en un 50%; esta reducción parece ser el factor más importante que produjo un aumento en los indices de abundancia relativa de Galeus melastomus, Scyliorhinus canicula y de las rayas, desde 1991 a 2009. Sin embargo la composición en especies de los Elasmobranquios no ha mostrado evidentes cambios en el tiempo, a pesar de muchas especies que han sufrido una disminución en la frecuencia de occurrencia. Por lo tanto, la interpretación de estos resultados como señal de recuperación de las poblaciones de elasmobranquios, necesita de una precaución especial. De hecho durante los últimos 50 años la fauna de elasmobranquios en el Mediterráneo ha sufrido una drástica reducción y todavía no se está observando ninguna considerable señal de recuperación

Discards of the Western Mediterranean trawl fleets

We present a quantitative analysis of the composition (commercialized catch and corresponding discard) of trawl catches, in seven ports of the western Mediterranean. Discards are defined here as the fraction of the catch from the haul that is returned to the sea by the fishermen, because it does not have commercial value. A sampling programme on board commercial was performed from June 1995 to June 1996. The hauls were sampled for the collection of the total catch in weight, by species, for the commercial and discarded fractions separately. The factors of stratification considered were in all the ports, depth, with three strata, stratum A (350 m), to which factor for two types of gear in the Porto Santo Stefano or two classes of vessel power in Vilanova were added. The results obtained have allowed to characterize the commercial and discards fractions. The discarded biomass always constituted an important fraction of the total catch. However, the discard of species with high commercial interest was very low or nilPublicado

Inferring relationships between pairs of individuals from locus heterozygosities

BACKGROUND: The traditional exact method for inferring relationships between individuals from genetic data is not easily applicable in all situations that may be encountered in several fields of applied genetics. This study describes an approach that gives affordable results and is easily applicable; it is based on the probabilities that two individuals share 0, 1 or both alleles at a locus identical by state. RESULTS: We show that these probabilities (z(i)) depend on locus heterozygosity (H), and are scarcely affected by variation of the distribution of allele frequencies. This allows us to obtain empirical curves relating z(i)'s to H for a series of common relationships, so that the likelihood ratio of a pair of relationships between any two individuals, given their genotypes at a locus, is a function of a single parameter, H. Application to large samples of mother-child and full-sib pairs shows that the statistical power of this method to infer the correct relationship is not much lower than the exact method. Analysis of a large database of STR data proves that locus heterozygosity does not vary significantly among Caucasian populations, apart from special cases, so that the likelihood ratio of the more common relationships between pairs of individuals may be obtained by looking at tabulated z(i )values. CONCLUSIONS: A simple method is provided, which may be used by any scientist with the help of a calculator or a spreadsheet to compute the likelihood ratios of common alternative relationships between pairs of individuals

Heparin Strongly Enhances the Formation of β2-Microglobulin Amyloid Fibrils in the Presence of Type I Collagen

The tissue specificity of fibrillar deposition in dialysis-related amyloidosis is most likely associated with the peculiar interaction of beta2-microglobulin (beta2-m) with collagen fibers. However, other co-factors such as glycosaminoglycans might facilitate amyloid formation. In this study we have investigated the role of heparin in the process of collagen-driven amyloidogenesis. In fact, heparin is a well known positive effector of fibrillogenesis, and the elucidation of its potential effect in this type of amyloidosis is particularly relevant because heparin is regularly given to patients subject to hemodialysis to prevent blood clotting. We have monitored by atomic force microscopy the formation of beta2-m amyloid fibrils in the presence of collagen fibers, and we have discovered that heparin strongly accelerates amyloid deposition. The mechanism of this effect is still largely unexplained. Using dynamic light scattering, we have found that heparin promotes beta2-m aggregation in solution at pH 6.4. Morphology and structure of fibrils obtained in the presence of collagen and heparin are highly similar to those of natural fibrils. The fibril surface topology, investigated by limited proteolysis, suggests that the general assembly of amyloid fibrils grown under these conditions and in vitro at low pH is similar. The exposure of these fibrils to trypsin generates a cleavage at the C-terminal of lysine 6 and creates the 7-99 truncated form of beta2-m (DeltaN6beta2-m) that is a ubiquitous constituent of the natural beta2-m fibrils. The formation of this beta2-m species, which has a strong propensity to aggregate, might play an important role in the acceleration of local amyloid deposition