Water-Tank Studies of Separating Flow Over Rough Hills

The present work investigates the lower boundary condition for flows over a steep, rough hill. Simple asymptotic arguments together with the mixing-length hypothesis are used to derive a local analytical solution that is tested against three different flow conditions. In all, 36 velocity profiles are compared with the proposed expression. The experiments were carried out in a water channel and velocity measurements were made through laser Doppler anemometry. The extent of separated flow was made to vary as a function of the roughness and the Reynolds number. The analysis includes regions of attached as well as separated flow. In particular, the solution of Stratford is studied at the points of separation and re-attachment and found to apply equally well in rough walls.     

Role of the Spanish scientific community in the initial assessment and management of the environmental damages caused by the Prestige oil spill

The role of the Spanish scientific community in the initial assessment of the environmental and socioeconomic damages caused by the Prestige oil spill is analysed. A discussion of the reasons for the failures in the response of the scientific community is presented, highlighting that despite the existence of adequate human capital and infrastructures, failures were related to the weakness of the structures and organisational capacity of the scientific institutions and the public administration. Some developments for an effective response to future catastrophes are proposed: (1) oceanographic and ecological models, including scientific and local knowledge; (2) management systems for scientific information; (3) organisational and incentive systems to allow the creation of temporary, large and well-organised multidisciplinary teams; (4) protocols for rapid, “real-time”, damage assessments; and (5) participation of different social groups (NGOs, fishers’ organisations, aquaculture industry or volunteer groups) in plans for the assessment and management of crises.     

Differential gene expression in oyster exposed to sewage

In order to investigate the influence of domestic sewage on the gene expression of Pacific oysters Crassostrea gigas, suppression subtractive hybridization (SSH) method was employed. Oysters were sampled at a farming area and, after 10 days of acclimation in the laboratory, were exposed to untreated domestic sewage diluted 33% for 48 h. Gills of male oysters were excised for total RNA extraction. mRNA was purified and the differential gene expression was analyzed by SSH. We obtained 61 cDNA sequences but only 15 were identified, which includes fatty acid binding protein, multidrug resistance protein, omega glutathione S-transferase, cytochrome P450 isoform CYP356A1, among others. The identified genes are associated with different metabolic functions like biotransformation, membrane transport, aerobic metabolism and translational machinery, evidencing the potential toxic effects elicited by these effluents.     

Effect of outplanting time on commercial cultivation of kelp <Emphasis Type="Italic">Laminaria saccharina</Emphasis> at the southern limit in the Atlantic coast,N.W. Spain

The aim of the study is to examine the influence of the outplanting time on the cultivation of the kelp Laminaria saccharina in the northwestern Spain, close to its southern limit of distribution in the North Atlantic coast. We compared two L. saccharina cultures outplanted in February and December. We found that the starting time of outplanting affects to the yield and the substantiality value, as well as the growth rate. The yield, the substantiality value and the growth rates of L. saccharina sporophytes obtained for the trial outplanted in December were significantly higher than those in February. These results can be mainly explained by the effect of temperature on the growth of L. saccharina sporophytes during cultivation. On the other hand, our results show that even in the southern limit of distribution of L. saccharina, the cultivation of this species was very profitable in high yield and quality.     

Age constraints in the double pulsar system J0737–3039

We investigate the age constraints that can be placed on the double pulsar system using models for the spin-down of the first-born 22.7-ms Pulsar A and the 2.77-s Pulsar B with characteristic ages of 210 and 50 Myr, respectively. Standard models assuming dipolar spin-down of both pulsars suggest that the time since the formation of Pulsar B is ∼50 Myr, that is, close to Pulsar B's characteristic age. However, adopting models which account for the impact of Pulsar A's relativistic wind on Pulsar B's spin-down, we find that the formation of Pulsar B took place either 80 or 180 Myr ago, depending on the interaction mechanism. Formation 80 Myr ago, closer to Pulsar B's characteristic age, would result in the contribution from J0737−3039 to the inferred coalescence rates for double neutron star binaries increasing by 40 per cent. The 180 Myr age is closer to Pulsar A's characteristic age and would be consistent with the most recent estimates of the coalescence rate. The new age constraints do not significantly impact recent estimates of the kick velocity, tilt angle between pre- and post-supernova orbital planes or pre-supernova mass of Pulsar B's progenitor.     

Arecibo timing and single-pulse observations of 17 pulsars

We have analysed the soft X-ray emission in a wide area of the Sculptor supercluster by using overlapping ROSAT Position Sensitive Proportional Counter pointings. After subtraction of the point sources, we have found evidence for extended, diffuse soft X-ray emission. We have investigated the nature of such extended emission through the cross-correlation with the density of galaxies as inferred from the Münster Redshift Survey. In particular, we have analysed the correlation as a function of the temperature of the X-ray emitting gas. We have found a significant correlation of the galaxy distribution only with the softest X-ray emission (0.1 – 0.3 keV) and only for gas temperatures   kT < 0.5 keV  . We have excluded the fact that this soft X-ray diffuse emission, and its correlation with the galaxy distribution, is significantly contributed by unresolved active galactic nuclei, groups of galaxies or individual galaxies. The most likely explanation is that the soft, diffuse X-ray emission is tracing warm–hot intergalactic medium, with temperatures below 0.5 keV, associated with the large-scale structures in the Sculptor supercluster.     

Fish bile as a biomarker for metal exposure

Fish accumulate several trace elements in muscle, gills and liver, however studies also indicate that metals can be excreted through bile. Since metal contamination leads to modifications in bile composition, biliary excretion offers an alternative way to evaluate the presence of trace-elements. Bile is easier to obtain than other organs and presents a simpler matrix, making it easier for chemical pre-treatment. To verify if bile can be useful as a biomonitoring tool for metal contamination, liver and bile trace element concentrations were determined and correlated. The Artificial Neural Networks statistical technique was used to verify if liver trace-element quantification could be substituted by bile analysis. Results show that significant correlations were obtained between trace elements in bile and liver and the ANN validated the hypothesis that certain trace-elements in bile could be utilized instead of liver trace-elements. Further studies in this field are of interest to further validate this biomarker.     

Multi-level geospatial modeling of human exposure patterns and vulnerability indicators

In the context of disaster risk management and in particular for improving preparedness and mitigation of potential impacts, information on socioeconomic characteristics including aspects of situation-specific human exposure and vulnerability is considered vital. This paper provides an overview on available multi-level geospatial information and modeling approaches from global to local scales that could serve as inventory for people involved in disaster-related areas. Concepts and applications related to the human exposure and social vulnerability domains are addressed by illustrating the varying dimensions and contextual implications. Datasets and methods are highlighted that can be applied to assess earthquake-related population exposure, ranging from global and continental-scale population grids (with a focus on recent developments for Europe) to high-resolution functional urban system models and space–time variation aspects. In a further step, the paper elaborates on the integration of social structure on regional scale and the development of aggregative social and economic vulnerability indicators which would eventually enable the differentiation of situation-specific risk patterns. The presented studies cover social vulnerability mapping for selected US federal states in the New Madrid seismic zone as well as the advancement of social vulnerability analysis through integration of additional economic features in the index construction by means of a case study for Turkey’s provinces.