Biogeochemical modeling at mass extinction boundaries

The causes of major mass extinctions is a subject of considerable interest to those concerned with the history and evolution of life on earth. The primary objectives of the proposed plan of research are: (1) to develop quantitative time-dependent biogeochemical cycle models, coupled with an ocean atmosphere in order to improve the understanding of global scale physical, chemical, and biological processes that control the distribution of elements important for life at times of mass extinctions; and (2) to develop a comprehensive data base of the best available geochemical, isotopic, and other relevant geologic data from sections across mass extinction boundaries. These data will be used to constrain and test the biogeochemical model. These modeling experiments should prove useful in: (1) determining the possible cause(s) of the environmental changes seen at bio-event boundaries; (2) identifying and quantifying little-known feedbacks among the oceans, atmosphere, and biosphere; and (3) providing additional insights into the possible responses of the earth system to perturbations of various timescales. One of the best known mass extinction events marks the Cretaceous/Tertiary (K/T) boundary (66 Myr ago). Data from the K/T boundary are used here to constrain a newly developed time-dependent biogeochemical cycle model that is designed to study transient behavior of the earth system. Model results predict significant fluctuations in ocean alkalinity, atmospheric CO2, and global temperatures caused by extinction of calcareous plankton and reduction in the sedimentation rates of pelagic carbonates and organic carbon. Oxygen-isotome and other paleoclimatic data from K/T time provide some evidence that such climatic fluctuations may have occurred, but stabilizing feedbacks may have acted to reduce the ocean alkalinity and carbon dioxide fluctuations

Strong ground motion in southern Portugal due to the 1755 Lisbon earthquake

The strong earthquake (M=8.8) that struck a large part of the Iberian Peninsula and Northern Morocco on November 1, 1755, was caused by the motion along a fault which localisation and spatial extent are still uncertain. According to recent numerical modelling of tsunami wave travel times, it seems that the tsunamigenic fault may be lo- cated off the southwestern coast of Portugal. Multi-channel seismic profiles in the area showed the existence of large submarine hills of tectonic origin, 100 km offshore Cabo de São Vincente, and led to the identification of active faults that may be responsible for the earthquake. E3D, a finite-difference seismic wave propagation code, is used to implement various source rupture scenarios. Based on available geophysical data and geological evidences, we propose a 3D velocity model of the upper mantle, crust, and sedimentary cover, for south Portugal and the adjacent Atlantic area. The model is constrained thanks to data available from recent instrumental earthquakes. We are able to test several possibilities, and to compare synthetic ground motion obtained onshore with historical evaluations of seismic intensity. Directivity of the source, as well as site effects, may explain the particular distribution of strong ground motion observations

The recent 2007 Portugal earthquake (Mw=6.1) in the seismotectonic context of the SW Atlantic area

An event of magnitude Mw 6.1(EMSC) occurred on 12/02/2007 at 10:35 UTC off coast of South-Western Portugal. The earthquake had its epicentre in the eastern Horseshoe Abyssal Plain, at 175 km South-West of San Vicente Cape (Figure 1). This earthquake is the largest earthquake since the great instrumental earthquake, Ms=8.0 (USGS), occurred on February 28th, 1969 in the same epicentral area. This earthquake was followed by four small aftershocks with magnitude less or equal to 3.5. There has been no reported damage associated to the event since habitated regions are too far away from the epicentre. This event has been widely felt in Portugal, particularly in the Algarve Region (I=IV – IM information), Southern Spain and Western Morocco and up to 700 km away of the epicentre (Salamanca, Madrid) (EMSC report in http://www.emsc-csem.org)

Universal Decoherence in Solids

Symmetry implications for the decoherence of quantum oscillations of a two-state system in a solid are studied. When the oscillation frequency is small compared to the Debye frequency, the universal lower bound on the decoherence due to the atomic environment is derived in terms of the macroscopic parameters of the solid, with no unknown interaction constants.Comment: 4 pages, no figure

Electric properties of granitic rocks

The objective of this work is to clarify the role of water content on the charge trans- port mechanisms of different granitic rocks. The mineralogical content of the rocks will also be taken into account. From the electrical point of view these materials are rather insulating porous media where charge injection creates different phenomena like build-up charges, space charge limited currents, surface effects and other behav- iors that resemble much a variety of oxides, like AlO

Detection and Quantification of Grass and Olea Airborne Pollen Allergens in Outdoor Air Samples and its Correlation with Pollen Counts

Detection and Quantification of Grass and Olea Airborne Pollen Allergens in Outdoor Air Samples and its Correlation with Pollen Counts R Ferro1*, R Ribeiro1*, MR Martins1,2, AT Caldeira1,3, E Caeiro6, CM Antunes1,5 & R Brandão2,4 and the HIALINE working group7 1Dep. of Chemistry, University of Evora, Portugal; 2Mediterranean Inst. Crop and Environment Sciences, Univ.Evora, Portugal; 3Centro Química, University of Évora, Portugal; 4Dep. Biology, University of Evora; 5Center for NeuroSciences and Cell Biology-University of Coimbra, Portugal; 6Soc.Portuguesa Alergol.Imunologia Clínica , Portugal 7 M. Thibaudon, France, M. Smith, United Kingdom, C. Galan, Spain R. Albertini, Italy, L. Grewling, Poland, G. Reese, Germany, A. Rantio-Lehtimäki, Finland, S. Jäger and U. Berger, Austria, M. Sofiev, Finland, I. Sauliene, Lithuania, L. Cecchi, Italy Presenting author: [email protected] tel: +351 266760889 Introduction: Allergic respiratory diseases broken out after an exposure to airborne pollen, as asthma and allergic rhinitis, are deeply increasing and they represent one of the major public health problems nowadays, affecting about 40% of European population. In Portugal, grass and Olea europaea pollen are certainly one of the main sources of athmospheric aeroallergens and as such, one of the main causes of respiratory allergy. For these reasons, it is useful the development of new strategies for prevention and treatment of these pathologies. The execution of aerobiological analysis including pollen calendars and/or immunoassays for the detection and quantification of allergens which could forecast the allergenic potential of the athmosphere are quite relevant since they would contribute to develop prevention measures of allergic respiratory diseases. The aim of this study was to evaluate the putative correlation between the concentration of some of the major allergens of and with their pollen counts. Methodology: On a meteorological platform at the town center of Evora (south Portugal), ambient air was sampled at 800L/min with a Chemvol high-volume cascade impactor equipped with stages PM>10µm, 10 µm>PM>2.5µm. The polyurethane impacting substrate was extracted with 0.1M NH4HCO3, pH8.1, supplemented with 0.1% BSA. The major pollen allergens from grass Phleum p 5 and olive Ole e 1 were determined with allergen specific ELISA´s. Airborne pollen of and Olea europaea simultaneously monitored with a Burkard Seven Day Recording Volumetric Spore Trap* , between the 30th of April and the 8th of July of 2009. Both samplers were placed side-by-side with air input at the same level. Results: During the pollen season of 2009, high values of grass pollen were recorded between May 2th and June 1 th. It was also observed that the air content of Phl p5 or Ole e1 aeroallergens were directly correlated with airborne pollen counts of Poaceae and Oleaceae, respectively. Conclusions: These results suggest that the directly quantification of aeroallergens may contribute, together with pollen counts of air samples, to define the allergic risk with higher precision. Acknowledgments: This study is integrated in the european project HIALINE (Executive Agency for Health and Consumers under grant agreement No 2008 11 07

Thrombus aspiration in patients with ST-elevation myocardial infarction: results of a national registry of interventional cardiology.

BACKGROUND: We aimed to evaluate the impact of thrombus aspiration (TA) during primary percutaneous coronary intervention (P-PCI) in 'real-world' settings. METHODS: We performed a retrospective study, using data from the National Registry of Interventional Cardiology (RNCI 2006-2012, Portugal) with ST-elevation myocardial infarction (STEMI) patients treated with P-PCI. The primary outcome, in-hospital mortality, was analysed through adjusted odds ratio (aOR) and 95% confidence intervals (95%CI). RESULTS: We assessed data for 9458 STEMI patients that undergone P-PCI (35% treated with TA). The risk of in-hospital mortality with TA (aOR 0.93, 95%CI:0.54-1.60) was not significantly decreased. After matching patients through the propensity score, TA reduced significantly the risk of in-hospital mortality (OR 0.58, 95%CI:0.35-0.98; 3500 patients). CONCLUSIONS: The whole cohort data does not support the routine use of TA in P-PCI, but the results of the propensity-score matched cohort suggests that the use of selective TA may improve the short-term risks of STEMI.info:eu-repo/semantics/publishedVersio

Minimal coupling method and the dissipative scalar field theory

Quantum field theory of a damped vibrating string as the simplest dissipative scalar field investigated by its coupling with an infinit number of Klein-Gordon fields as the environment by introducing a minimal coupling method. Heisenberg equation containing a dissipative term proportional to velocity obtained for a special choice of coupling function and quantum dynamics for such a dissipative system investigated. Some kinematical relations calculated by tracing out the environment degrees of freedom. The rate of energy flowing between the system and it's environment obtained.Comment: 15 pages, no figur

Exact Solution of a Boundary Conformal Field Theory

We study the conformal field theory of a free massless scalar field living on the half line with interactions introduced via a periodic potential at the boundary. An SU(2) current algebra underlies this system and the interacting boundary state is given by a global SU(2) rotation of the left-moving fields in the zero-potential (Neumann) boundary state. As the potential strength varies from zero to infinity, the boundary state interpolates between the Neumann and the Dirichlet values. The full S-matrix for scattering from the boundary, with arbitrary particle production, is explicitly computed. To maintain unitarity, it is necessary to attribute a hidden discrete ``soliton'' degree of freedom to the boundary. The same unitarity puzzle occurs in the Kondo problem, and we anticipate a similar solution.Comment: harvmac and epsf, 36 pages with 5 figures; v2: the version which appeared in NPB including a Note Added on the band structure of open string

SEISMO-ELECTROMAGNETIC PHENOMENA IN TECTONICALLY ACTIVE REGIONS

This work presents a research plan that aims to monitor seismo-electromagnetic signals in seismic active regions. Two effects will be considered: electromagnetic field emissions and radio broadcastings. Our study will be focused in the analysis of low magnitude earthquakes almost completely disregarded in literature. We aim to collect novel seismo-electromagnetic emission data emerging from seismic activity. We expect to address the time variation of electromagnetic properties of the crust in relation with the strain field and complement it with the development of proper models. Experimental studies based on the electrical properties of rocks will also be done aiming the understanding of pressure stimulated currents and voltages that produce detectable electromagnetic radiation and can be a cause for seismo-electromagnetic signals