Vertical-axis rotations and deformation along the active strike-slip El Tigre Fault (Precordillera of San Juan,Argentina) assessed through palaeomagnetism and anisotropy of magnetic susceptibility

International Journal of Earth Sciences - Palaeomagnetic data from poorly consolidated to non-consolidated late Cenozoic sediments along the central segment of the active El Tigre Fault...     

Influence of relative density and stress level on the bearing capacity of sands

A finite element approach is presented to determine the bearing capacity of shallow footings on silica sand deposits. The approach can take into account the effects of relative density and stress level on the shear strength of granular soil and is applicable to a fairly large effective stress range. The strength of sand is characterized by a non-linear Mohr–Coulomb criterion which depends on maximum and critical friction angles, widely used parameters in engineering practice. The results of analysis indicate that this approach yields reliable predictions of bearing capacity and, in particular, it can model the volumetric behaviour of the soil at failure.     

Deep sea diapirs and bottom simulating reflector in Fairway Basin (SW Pacific)

A recent swath-bathymetry and geophysical survey of the R/V L'Atalante in the Fairway Basin between Australia and New Caledonia allowed to confirm the Cretaceous age of the creation of the basin by continental stretching. This first stage of opening of the Fairway Basin is associated with the deposition of a continuous salt/mud layer feeding today numerous diapirs, some of them piercing the 3 to 4 km thick sedimentary cover and reaching the seafloor. In close link with this salt/mud layer a Bottom Simulating Reflector indicator of gas hydrates level occupies a 70000 km² surface at about 500 to 600 m-depth beneath the sea floor. The coexistence of both BSR and diapirs suggests a thermogenic better than biogenic origin for the gas hydrates horizon.     

Life cycle of Marphysa sanguinea (Polychaeta: Eunicidae) in the Venice Lagoon (Italy)

The life cycle of a brackish water population of Marphysa sanguinea (Polychaeta Eunicidae), from the Venice Lagoon (Italy), was investigated from April 1993 to August 1994. Marphysa sanguinea is a large‐sized gonochoric species with annual iteroparous strategy and synchronous spawning at population level. The sex‐ratio was close to 1:1. There were no morphological differences between males and females and spawning occurred without epitokal metamorphosis. The gonadial activity was maximum during summer period in both sexes. From May to September in the females, the greater number of immature oocytes could be observed; starting from November immature oocytes decreased and progressively those with a wider diameter increased in number. Spawning took place in April–May and generally not all eggs were spawned, a small proportion being kept as a reserve material for the following gamete production. The pelagic phase (trochophore and metatrochophore stages) was short (2–3 days). The reduction in the dispersal phase, together with the development of a strong anterior musculature, brought to an early acquisition of the benthic habit, which was attained with the construction of the mucous tube inside of which the larva lived. The results highlighted that colonization of brackish environments took place thanks to morphological and physiological features that allow this species to live in a sediment layer characterized by the stability of the physical and chemical characteristics of the substratum.     

Modeling IR spectral energy distributions: a?pilot study of?starburst parameters and silicate absorption curves for some GOALS galaxies

This paper describes a pilot study into the spectral energy distribution (SED) fitting and the derivation of physical parameters for 19 galaxies observed as part of the Great Observatories All-sky LIRG Survey (GOALS) survey as observed with the Spitzer Space Telescope. For this we have used the pan-spectral fitting tools developed in a series of papers by Dopita and his co-workers. We show that the standard Lee and Draine ??astronomical silicate?? model cannot provide a good fit to the silicate absorption features as observed in the heavily dust-extinguished (A _V??50 mag.) starbursts. We have derived an empirical fit to the ??starburst silicate?? absorption in these objects. This absorption curve is consistent with the silicate grains being systematically larger in starburst environments than in the local Galactic interstellar medium. We demonstrate the sensitivity of the SED fitting to each of the fitted parameters, and derive these parameters for those galaxies which do not have an embedded AGN. This technique is simple and provides reasonably robust and uniform parameters for the starburst, especially as far as the star formation rate, population of old stars, compactness of the starburst region and total foreground extinction are concerned. However, the chemical abundances and the optical extinction cannot be reliably determined by this analysis, and optical SEDs will also be required to provide a complete characterization of the starburst region and of the surrounding galaxy.     

Staying cool in a changing climate: Reaching vulnerable populations during heat events

The frequency and intensity of hot weather events are expected to increase globally, threatening human health, especially among the elderly, poor, and chronically ill. Current literature indicates that emergency preparedness plans, heat health warning systems, and related interventions may not be reaching or supporting behavior change among those most vulnerable in heat events. Using a qualitative multiple case study design, we comprehensively examined practices of these populations to stay cool during hot weather (“cooling behaviors”) in four U.S. cities with documented racial/ethnic and socio-economic disparities and diverse heat preparedness strategies: Phoenix, Arizona; Detroit, Michigan; New York City, New York; and Philadelphia, Pennsylvania. Based on semi-structured in-depth interviews we conducted with 173 community members and organizational leaders during 2009–2010, we assessed why vulnerable populations do or do not participate in health-promoting behaviors at home or in their community during heat events, inquiring about perceptions of heat-related threats and vulnerability and the role of social support. While vulnerable populations often recognize heat's potential health threats, many overlook or disassociate from risk factors or rely on experiences living in or visiting warmer climates as a protective factor. Many adopt basic cooling behaviors, but unknowingly harmful behaviors such as improper use of fans and heating and cooling systems are also adopted. Decision-making related to commonly promoted behaviors such as air conditioner use and cooling center attendance is complex, and these resources are often inaccessible financially, physically, or culturally. Interviewees expressed how interpersonal, intergenerational relationships are generally but not always protective, where peer relationships are a valuable mechanism for facilitating cooling behaviors among the elderly during heat events. To prevent disparities in heat morbidity and mortality in an increasingly changing climate, we note the implications of local context, and we broadly inform heat preparedness plans, interventions, and messages by sharing the perspectives and words of community members representing vulnerable populations and leaders who work most closely with them.     

Constraining and enabling factors to using long-term climate information in decision-making

We carry out a structured review of the peer-reviewed literature to assess the factors that constrain and enable the uptake of long-term climate information in a wide range of sectoral investment and planning decisions. Common applications of long-term climate information are shown to relate to urban planning and infrastructure, as well as flood and coastal management. Analysis of the identified literature highlights five categories of constraints: disconnection between users and producers of climate information, limitations of climate information, financial and technical constraints, political economy and institutional constraints and finally psycho-social constraints. Five categories of enablers to the uptake of long-term climate information in decision-making are also identified: collaboration and bridge work, increased accessibility of climate information, improvement in the underlying science, institutional reform and windows of opportunity for building trust.

Policy relevance

Our review suggests that stand-alone interventions aimed at promoting the uptake of climate information into decision-making are unlikely to succeed without genuine and sustained relationships between producers and users. We also highlight that not every decision requires consideration of long-term climate information for successful outcomes to be achieved. This is particularly the case in the context of developing countries, where the immediacy of development challenges means that decision makers often prioritize short-term interventions. Care should therefore be taken to ensure that information is targeted towards investments and planning decisions that are relevant to longer-term timescales.     

Is the toxic dinoflagellate Ostreopsis cf. ovata harmful to Mediterranean benthic invertebrates? Evidences from ecotoxicological tests with the polychaete Dinophilus gyrociliatus

Toxicity tests were performed exposing the polychaete Dinophilus gyrociliatus to seawater samples containing the toxic dinoflagellate Ostreopsis cf. ovata. Experiments were carried out twice in mid summer, when O. cf. ovata bloomed, and twice in late summer, when the dinoflagellate density declined. Each time, four treatments were considered: original sample; reference sample, which always contained 200 O. cf. ovata?cells?ml(-1); filtered-seawater sample; artificial seawater (control). All the time, almost all worms survived in the controls and filtered-seawater treatments. In mid summer, the mortality of worms in the treatments containing O. cf. ovata was high and density-dependent. On the other hand, mortality in groups exposed to the original and reference samples collected in late summer was negligible. The high per cell toxicity of O. cf. ovata during mid summer could represent an allelopathic response. The test with D.?gyrociliatus appears to be a promising tool for assessing the ecological risk of toxic dinoflagellate blooms.