133 research outputs found

    Extreme wave events in the southeastern Iberia coast: Blocks and megablocks as an indicator of tsunamis or extreme storms

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    Whilst the SW coast of the Iberian Peninsula has a significant record of extreme wave events (EWE), mostly associated with tsunamis, the Mediterranean coast offers a smaller record of these events, although some historical tsunamis with limited impact have been cited on the coast. In general, these studies have been based on the geological record of detrital sequences of sands and silts. In this case, we have focused on the study of coastal deposits of blocks and megablocks in Cope, Murcia (SE of Iberian Peninsula). Here, blocks greater than 1 m and located up to 4 masl were generated by an EWE associated to either a tsunamis or great storm. An unmanned aerial vehicle (drone) has been utilized to perform aerial photogrammetry, which complemented terrestrial photogrammetry of higher resolution.This has been processed to develop a 3D model of the terrain and obtain the dimensional and spatial parameters of these blocks. Different models have been used to calculate potential tsunami wave heights and scale of storms capable of generating such deposits (Nott, 2003; Engel and May, 2012). The results confirm the process of generating force required to generate the block ridges at this site

    An analytical solver for the multi-group two-dimensional neutron-diffusion equation by integral transform techniques

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    In this work, we present an analytical solver for neutron diffusion in a rectangular two-dimensional geometry by a two-step integral transform procedure. To this end, we consider a regionwise homogeneous problem for two energy groups, i.e. fast and thermal neutrons, respectively. Each region has its specific physical properties, specified by cross-sections and diffusion constants. The problem is set up by two coupled bi-dimensional diffusion equations in agreement with general perturbation theory. These are solved by integral transforms Laplace transform and generalized integral transform technique yielding analytical expressions for the scalar neutron fluxes. The solutions for neutron fluxes are presented for fast and thermal neutrons in the four regions

    Structural basis for the enhanced activity of cyclic antimicrobial peptides:The case of BPC194

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    AbstractWe report the molecular basis for the differences in activity of cyclic and linear antimicrobial peptides. We iteratively performed atomistic molecular dynamics simulations and biophysical measurements to probe the interaction of a cyclic antimicrobial peptide and its inactive linear analogue with model membranes. We establish that, relative to the linear peptide, the cyclic one binds stronger to negatively charged membranes. We show that only the cyclic peptide folds at the membrane interface and adopts a β-sheet structure characterised by two turns. Subsequently, the cyclic peptide penetrates deeper into the bilayer while the linear peptide remains essentially at the surface. Finally, based on our comparative study, we propose a model characterising the mode of action of cyclic antimicrobial peptides. The results provide a chemical rationale for enhanced activity in certain cyclic antimicrobial peptides and can be used as a guideline for design of novel antimicrobial peptides

    Amidated and ibuprofen-conjugated kyotorphins promote neuronal rescue and memory recovery in cerebral hypoperfusion dementia model

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    Copyright © 2016 Sá Santos, Santos, Pinto, Ramu, Heras, Bardaji, Tavares and Castanho. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.Chronic brain ischemia is a prominent risk factor for neurological dysfunction and progression for dementias, including Alzheimer's disease (AD). In rats, permanent bilateral common carotid artery occlusion (2VO) causes a progressive neurodegeneration in the hippocampus, learning deficits and memory loss as it occurs in AD. Kyotorphin (KTP) is an endogenous antinociceptive dipeptide whose role as neuromodulator/neuroprotector has been suggested. Recently, we designed two analgesic KTP-derivatives, KTP-amide (KTP-NH2) and KTP-NH2 linked to ibuprofen (IbKTP-NH2) to improve KTP brain targeting. This study investigated the effects of KTP-derivatives on cognitive/behavioral functions (motor/spatial memory/nociception) and hippocampal pathology of female rats in chronic cerebral hypoperfusion (2VO-rat model). 2VO-animals were treated with KTP-NH2 or IbKTP-NH2 for 7 days at weeks 2 and 5 post-surgery. After behavioral testing (week 6), coronal sections of hippocampus were H&E-stained or immunolabeled for the cellular markers GFAP (astrocytes) and NFL (neurons). Our findings show that KTP-derivatives, mainly IbKTP-NH2, enhanced cognitive impairment of 2VO-animals and prevented neuronal damage in hippocampal CA1 subfield, suggesting their potential usefulness for the treatment of dementia.Funding was provided by the Portuguese Agency Fundação para a Ciência e a Tecnologia SFRH/BPD/79542/2011 fellowship)info:eu-repo/semantics/publishedVersio

    Oscilaciones eustáticas e implicaciones climáticas en el tránsito Neógeno-Cuaternario en la isla de Sal (archipiélago de Cabo Verde)

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    Solution pipes interpreted as a cryptokarst separate large-scale cross-bedded megaforms of shallowmarine calcarenites deposited at the Neogene-Quatemary transition in Cape Verde Islands. This implies that depositional phases were followed by subaerial exposure of the cemented calcarenites during subsequent falls of sea level, and accumulation of unconsolidated eolianites which supported a vegetal cover that promoted the cryptokarst. The process was repeated several times. A widespread, more recent karstification with red silty clay filling of voids may represent the aridification of climate at the beginning oi the Quaternary and the increased supply of Saharan dust by Trade Winds

    Determinants of Use of Intermittent Preventive Treatment of Malaria in Pregnancy: Jinja, Uganda

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    BACKGROUND: Maternal malaria is associated with serious adverse pregnancy outcomes. One recommended means of preventing malaria during pregnancy is intermittent preventive therapy (IPTp) with sulfadoxine/pyrimethamine (SP). We sought to identify determinants of preventive use of SP during pregnancy among recently pregnant women in Uganda. Additionally, we characterized the timing of and indications for the administration of SP at antenatal care (ANC) visits and missed opportunities for SP administration. METHODOLOGY/PRINCIPAL FINDINGS: Utilizing a population-based random sample, we interviewed 500 women living in Jinja, Uganda who had been pregnant in the past year. Thirty-eight percent (192/500) of women received SP for the treatment of malaria and were excluded from the analysis of IPTp-SP. Of the remaining women, 275 (89.3%) reported at least two ANC visits after the first trimester and had an opportunity to receive IPTp-SP according to the Ugandan guidelines, but only 86 (31.3%) of these women received a full two-dose course of IPTp. The remaining 189 (68.7%) women missed one or more doses of IPTp-SP. Among the 168 women that were offered IPTp, 164 (97.6%) of them took the dose of SP. CONCLUSIONS/SIGNIFICANCE: Use of IPTp in Uganda was found to be far below target levels. Our results suggest that women will take SP for IPTp if it is offered during an ANC visit. Missed opportunities to administer IPTp-SP during ANC were common in our study, suggesting provider-level improvements are needed

    Catalogue of the geological and environmental effects of earthquakes in Spain in the ESI-2007 Macroseismic Scale and their application to paleoseismology

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    Este trabajo resume la contribución del grupo de trabajo español sobre efectos geológicos y ambientales de los terremotos en la elaboración de la escala macrosísmica ESI-2007 promovida por la subcomisión de paleosismología de INQUA. En la actualidad se han clasificado 20 eventos sísmicos, 7 instrumentales y 13 históricos. La mayoría se encuentran incluidos en los catálogos sísmicos existentes salvo dos de los que sólo existen evidencias en el registro geológico o arqueológico (Tobarra y Baelo Claudia). Se han catalogado un total de 103 efectos geológicos para los eventos mencionados, de los cuales 32 se han implementado en la base de datos EEE de INQUA. Los datos recogidos en el presente catálogo cubren intensidades desde VI a X de la escala convencional MSK, con magnitudes (Ms) asociadas entre 4,3 y 6,7. En los eventos analizados las intensidades ESI-07 estimadas provisionalmente resultan similares a las MSK y se sitúan entre uno o dos grados por encima de las intensidades EMS correspondientes.This work summarizes the contribution of the Spanish working group on the Earthquake Environmental Effects (EEE) for their implementation in the ESI-2007 macroseismic Intensity Scale promoted by the INQUA Subcomission on Paleoseismology. At present the Spanish working group has classified a total amount of 20 seismic events, 7 of them instrumental earthquakes and the other 13 historical ones. While two of the historical ones are only evidenced by geological, geomorphological (Tobarra, Albacete) and archaeological data (Baelo Claudia,, Cádiz), the rest are well documented in historical sources and existing seismic catalogues. From the bulk 103 site locality effects cataloged a total of 32 EEE files have been completed, which have been already implemented in the EEE INQUA data-base. The Spanish data cover intensity degrees from VI to X of the conventional MSK Scale, with associated magnitudes (Ms) from 4.3 to 6.7. The analysed events result in estimated ESI-07 intensities similar to that of the MSK conventional scale, but one or two degrees higher than those resulting from the EMS scale estimations.Depto. de Geodinámica, Estratigrafía y PaleontologíaFac. de Ciencias GeológicasTRUEpu

    KAP Degradation by Calpain Is Associated with CK2 Phosphorylation and Provides a Novel Mechanism for Cyclosporine A-Induced Proximal Tubule Injury

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    The use of cyclosporine A (CsA) is limited by its severe nephrotoxicity that includes reversible vasoconstrictor effects and proximal tubule cell injury, the latter associated whith chronic kidney disease progression. The mechanisms of CsA-induced tubular injury, mainly on the S3 segment, have not been completely elucidated. Kidney androgen-regulated protein (KAP) is exclusively expressed in kidney proximal tubule cells, interacts with the CsA-binding protein cyclophilin B and its expression diminishes in kidneys of CsA-treated mice. Since we reported that KAP protects against CsA toxicity in cultured proximal tubule cells, we hypothesized that low KAP levels found in kidneys of CsA-treated mice might correlate with proximal tubule cell injury. To test this hypothesis, we used KAP Tg mice developed in our laboratory and showed that these mice are more resistant to CsA-induced tubular injury than control littermates. Furthermore, we found that calpain, which was activated by CsA in cell cultures and kidney, is involved in KAP degradation and observed that phosphorylation of serine and threonine residues found in KAP PEST sequences by protein kinase CK2 enhances KAP degradation by calpain. Moreover, we also observed that CK2 inhibition protected against CsA-induced cytotoxicity. These findings point to a novel mechanism for CsA-induced kidney toxicity that might be useful in developing therapeutic strategies aimed at preventing tubular cell damage while maintaining the immunosuppressive effects of CsA
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