99 research outputs found
Paleogeografía sísmica de zonas costeras en la Península Ibérica: su impacto en el análisis de terremotos antiguos e históricos en España
This paper presents three examples of ancient earthquakes occurring in coastal areas of the S and SE of the Iberian Peninsula (218 BC, AD 40-60 and AD 1048) with the aim of illustrating the use of geological and archaeological data in their macroseismic characterization. Historical information for ancient earthquakes that occurred in Spain prior to the 10th century is scarce or non-existent. This paper shows that the current state of knowledge on palaeoseismology and archaeoseismology on these ancient events clearly exceeds the existing historical information allowing the increase of macroseismic information points by using the ESI-07 scale (Environmental Seismic Intensity). Consequently, the geologic analyses of ancient earthquakes contribute to their understanding and parametric evaluations, and improve further advances in seismic hazard assessments. The most significant issue outlined in the present paper is the analysis of the ancient palaeogeography of the affected areas. The studied examples analysed were located in open estuarine areas that have been filled by fluvial sediments or anthropogenic fills over time. The effects of the 218 BC earthquake-tsunami event in the Gulf of Cadiz are analysed in estuarine areas, and especially in the ancient Roman Lagus Ligustinus (Guadalquivir Depression marshes); the effects of the earthquake in AD 40-60 is analysed in the old Roman city of Baelo Claudia located in the Bolonia Bay (Strait of Gibraltar); and the effects of the earthquake of AD 1048on the ancient Sinus Ilicitanus (Bajo Segura Depression) during Muslim times. Descriptions from Roman and Arabic geographers are cross-checked with existing palaeogeographic models based on geological data. This type of analysis results in ancient macroseismic scenarios for the interpretation of theoretical distributions of intensities and environmental effects supporting the concept of “seismic palaeogeography” proposed in this paperEl presente trabajo recoge tres ejemplos de terremotos antiguos (218 AC, 40-60 AD y 1048 AD) ocurridos en zonas litorales del S y SO de la Península Ibérica con la intención de ilustrar el uso de datos geológicos y ar¬queológicos en la caracterización macrosísmica de los mismos. En la mayor parte de los sísmos ocurridos con anterioridad al siglo X d.C. la información documental histórica que se posee es muy escasa o inexistente. El presente trabajo muestra que el actual estado de conocimiento en paleosismología y arqueosismologia sobre este tipo de terremotos sobrepasa con creces la información documental histórica, permitiendo la multiplica¬ción de los puntos de información macrosísmica mediante el uso de la escala ESI-07 (Environmental Seismic Intensity). Consecuentemente, el análisis geológico de los terremotos antiguos mejora su conocimiento y análisis paramétrico, permitiendo avanzar la evaluación de la peligrosidad sísmica de las zonas afectadas. El aspecto que se pone de especial relieve en este trabajo es el análisis de la paleogeografía existente en la antigüedad, ya que todas las zonas (afectadas) analizadas en este trabajo corresponden a zonas estuarinas abiertas que se han ido rellenado por aportes fluviales o de forma artificial con el tiempo. Se analizan los efectos del terremoto de 218 AC en las zonas estuarinas del Golfo de Cádiz y muy especialmente en el antiguo Lacus Ligustinus (marismas del Guadalquivir) durante época romana; los efectos del terremoto de 40-60 AD en la antigua Bahía de Baelo Claudia (Estrecho de Gibraltar); y los efectos del terremoto de 1048 AD en el antiguo Sinus ilicitanus (Depresión del Bajo Segura) durante época musulmana. Se han cotejado descripciones de geógrafos romanos y árabes con modelos basados en datos geológicos. Este tipo de análisis ha permitido generar antiguos escenarios macrosísmicos basados en la paleogeografía y reinterpretar las distribuciones teóricas de intensidades y los efectos ambientales de los terremotos estudiados que es a lo que se refiere el concepto de “paleogeografía sísmica” propuesto en este trabajoThis work has been funded by the Spanish-FEDER research projects CGL2012-37281 C02.01 (QTECTBETICA-USAL), CGL2012-33430 (CSIC) and CGL2013-42847-R (UNED
Molecular Gastronomy in Spain
[EN] Beyond the overwhelming international success of Ferrán Adria, Spain has been one of the countries with a more active implication in molecular gastronomy as a scientific discipline but also in the use of ingredients, technologies, and equipment from the scientificand technological universe in the culinary area. Nowadays, this is a well-established discipline in Spain, with a number of research groups covering related topics, several companies commercializing appliances and additives worldwide, and renowned
international chefs and many restaurants and companies committed
to the collaboration with scientists for facing the future of
Spanish gastronomyThe authors would like to thank the Ministerio de Ciencia e Innovación (Spain) for funding the Collaborative Network “INDAGA” (AGL2007-28589- E/ALI; AGL2009-05765-E), which enabled their collaboration.García Segovia, P.; Garrido, MD.; Vercet Tormo, A.; Arboleya, JC.; Fiszman Dal Santo, S.; Martínez Monzó, J.; Laguarda, S.... (2014). Molecular Gastronomy in Spain. Journal of Culinary Science and Technology. 12(4):279-293. https://doi.org/10.1080/15428052.2014.914813S27929312
Sea level and climate changes during OIS 5e in the Western Mediterranean
Palaeontological, geomorphological and sedimentological data supported by isotopic dating on Oxygen
Isotopic Stage (OIS) 5e deposits from the Spanish Mediterranean coast, are interpreted with the aim of
reconstructing climatic instability in the Northern Hemisphere. Data point to marked climatic instability
during the Last Interglacial (OIS 5e), with a change in meteorological conditions and, consequently, in the
sedimentary environment. The oolitic facies generated during the first part of OIS 5e (ca. 135 kyr) shift into
reddish conglomeratic facies during the second part (ca. 117 kyr). Sea surface Temperature (SST) and salinity
are interpreted mainly on the basis of warm Senegalese fauna, which show chronological and spatial
differential distribution throughout the Western Mediterranean. Present hydrological and meteorological
conditions are used also as modern analogues to reconstruct climatic variability throughout the Last
Interglacial, and this variability is interpreted within the wider framework of the North Atlantic record. All
the available data indicate an increase in storminess induced by an increase in the influence of northwesterlies,
a slight drop of SST in the northern Western Mediterranean, and an important change in
meteorological conditions at the end of OIS 5e (117 kyr). These changes correlate well with the decrease in
summer insolation and with the climatic instability recorded in North Atlantic high latitudes
Drilling Predation on Serpulid Polychaetes (Ditrupa arietina) from the Pliocene of the Cope Basin, Murcia Region, Southeastern Spain
We report quantitative analyses of drilling predation on the free-living, tube-dwelling serpulid polychaete Ditrupa arietina from the Cope Cabo marine succession (Pliocene, Spain). Tubes of D. arietina are abundant in the sampled units: 9 bulk samples from 5 horizons yielded ∼5925 specimens of D. arietina. Except for fragmentation, tubes were well preserved. Complete specimens ranged from 3.1 to 13.4 mm in length and displayed allometric growth patterns, with larger specimens being relatively slimmer. Drilled Ditrupa tubes were observed in all samples. Drillholes, identified as Oichnus paraboloides, were characterized by circular to elliptical outline (drillhole eccentricity increased with its diameter), parabolic vertical profile, outer diameter larger than inner diameter, penetration of one tube wall only, narrow range of drill-hole sizes, and non-random (anterior) distribution of drillholes. A total of 233 drilled specimens were identified, with drilling frequencies varying across horizons from 2.7% to 21% (3.9% for pooled data). Many tube fragments were broken across a drillhole suggesting that the reported frequencies are conservative and that biologically-facilitated (drill-hole induced) fragmentation hampers fossil preservation of complete serpulid tubes. No failed or repaired holes were observed. Multiple complete drillholes were present (3.9%). Drilled specimens were significantly smaller than undrilled specimens and tube length and drill-hole diameter were weakly correlated. The results suggest that drillholes were produced by a size-selective, site-stereotypic predatory organism of unknown affinity. The qualitative and quantitative patterns reported here are mostly consistent with previous reports on recent and fossil Ditrupa and reveal parallels with drilling patterns documented for scaphopod mollusks, a group that is ecologically and morphologically similar to Ditrupa. Consistent with previous studies, the results suggest that free-dwelling serpulid polychaetes are preyed upon by drilling predators and may provide a viable source of data on biotic interactions in the fossil record
Sea level changes during the last and present interglacials in Sal Island (Cape Verde archipelago)
Last interglacial and Holocene deposits are particularly well developed in the southern parts of Sal Island (Cape
Verde Archipelago). They primarily consist of low-elevation (≤2 m above sea level [a.s.l.]) marine deposits
made of a basal conglomerate embedded in carbonate mud, passing upwards to calcarenites. All deposits
contain an abundant fauna with corals, algae and molluscs with Strombus latus Gmelin and accompanying
warm water species of the “Senegalese” fauna. Small scale geomorphological mapping with detailed
morphosedimentary analysis revealed lateral facies changes and imbricate (offlapping) structures that suggest
small-scale oscillations of paleo-sealevels during high sea stand intervals. U-series measurements (in coral
fragments) allowed unequivocal identification of Marine Isotope Substage (MIS) 5.5 units, but were not
precise enough to date the sea level oscillations of the interval. However, geomorphological data and
sedimentary facies analysis suggest a double sea level highstand during the peak of the last interglacial.
MIS 5.5 age deposits occur at Sal and the Canary Islands at low topographic elevations, between 1 and 2 masl.
However, these values are lower than the elevations measured for the correlative terraces outcropping at the
western tropical Atlantic islands, widely considered to be tectonically stable.
Combining the results in this paper with earlier investigations of the “Senegalese” fauna distribution as far
north as the Mediterranean basin, it is suggested that the last-interglacial oceanic temperatures in this basin, as
well as the temperatures in other islands of the Eastern Atlantic and the coasts of Morocco, were warmer than
modern temperatures
Prediction of Antibacterial Activity from Physicochemical Properties of Antimicrobial Peptides
Consensus is gathering that antimicrobial peptides that exert their antibacterial action at the membrane level must reach a local concentration threshold to become active. Studies of peptide interaction with model membranes do identify such disruptive thresholds but demonstrations of the possible correlation of these with the in vivo onset of activity have only recently been proposed. In addition, such thresholds observed in model membranes occur at local peptide concentrations close to full membrane coverage. In this work we fully develop an interaction model of antimicrobial peptides with biological membranes; by exploring the consequences of the underlying partition formalism we arrive at a relationship that provides antibacterial activity prediction from two biophysical parameters: the affinity of the peptide to the membrane and the critical bound peptide to lipid ratio. A straightforward and robust method to implement this relationship, with potential application to high-throughput screening approaches, is presented and tested. In addition, disruptive thresholds in model membranes and the onset of antibacterial peptide activity are shown to occur over the same range of locally bound peptide concentrations (10 to 100 mM), which conciliates the two types of observations
Group B streptococcus infection during pregnancy and infancy: estimates of regional and global burden.
BACKGROUND: Group B streptococcus (GBS) colonisation during pregnancy can lead to invasive GBS disease (iGBS) in infants, including meningitis or sepsis, with a high mortality risk. Other outcomes include stillbirths, maternal infections, and prematurity. There are data gaps, notably regarding neurodevelopmental impairment (NDI), especially after iGBS sepsis, which have limited previous global estimates. In this study, we aimed to address this gap using newly available multicountry datasets. METHODS: We collated and meta-analysed summary data, primarily identified in a series of systematic reviews published in 2017 but also from recent studies on NDI and stillbirths, using Bayesian hierarchical models, and estimated the burden for 183 countries in 2020 regarding: maternal GBS colonisation, iGBS cases and deaths in infants younger than 3 months, children surviving iGBS affected by NDI, and maternal iGBS cases. We analysed the proportion of stillbirths with GBS and applied this to the UN-estimated stillbirth risk per country. Excess preterm births associated with maternal GBS colonisation were calculated using meta-analysis and national preterm birth rates. FINDINGS: Data from the seven systematic reviews, published in 2017, that informed the previous burden estimation (a total of 515 data points) were combined with new data (17 data points) from large multicountry studies on neurodevelopmental impairment (two studies) and stillbirths (one study). A posterior median of 19·7 million (95% posterior interval 17·9-21·9) pregnant women were estimated to have rectovaginal colonisation with GBS in 2020. 231 800 (114 100-455 000) early-onset and 162 200 (70 200-394 400) late-onset infant iGBS cases were estimated to have occurred. In an analysis assuming a higher case fatality rate in the absence of a skilled birth attendant, 91 900 (44 800-187 800) iGBS infant deaths were estimated; in an analysis without this assumption, 58 300 (26 500-125 800) infant deaths from iGBS were estimated. 37 100 children who recovered from iGBS (14 600-96 200) were predicted to develop moderate or severe NDI. 40 500 (21 500-66 200) maternal iGBS cases and 46 200 (20 300-111 300) GBS stillbirths were predicted in 2020. GBS colonisation was also estimated to be potentially associated with considerable numbers of preterm births. INTERPRETATION: Our analysis provides a comprehensive assessment of the pregnancy-related GBS burden. The Bayesian approach enabled coherent propagation of uncertainty, which is considerable, notably regarding GBS-associated preterm births. Our findings on both the acute and long-term consequences of iGBS have public health implications for understanding the value of investment in maternal GBS immunisation and other preventive strategies. FUNDING: Bill & Melinda Gates Foundation
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