Contributions of the ostracode population analysis: paleoenvironmental evolution of the southwestern sector of the Doñana National Park (SW Spain) during the Late Holocene

El análisis de los ostrácodos extraídos en dos testigos tomados en el sector sudoccidental del Parque Nacional de Doñana permite deducir su evolución durante el Holoceno Superior. En los últimos 2.400-2.300 años BP se ha producido la transición desde un lagoon, habitado básicamente por Cyprideis torosa (Jones), Loxoconcha elliptica (Brady) y Leptocythere castanea (Sars), hasta la actual laguna de aguas dulces, con numerosos individuos de Cyprinotus salinus (Brady) y Herpetocypris chevreuxi (Sars). En este período, diversos eventos energéticos (¿tormentas, tsunamis?) han quedado reflejados en un aumento en la proporción de adultos de Cyprideis torosa y en los porcentajes de especies marinas.The ostracode analysis of two cores collected in the southwestern area of the Doñana National Park permits to deduce its evolution during the Late Holocene. In the last 2,400-2,300 years BP, there was a transition from a lagoon, inhabited mainly by Cyprideis torosa (Jones), Loxoconcha elliptica (Brady) and Leptocythere castanea (Sars), to the present-day fresh-water pond, with numerous individuals of Cyprinotus salinus (Brady) and Herpetocypris chevreuxi (Sars). In this period, different energetic events (storms?, tsunamis?) have been deduced from both the higher adult proportions of Cyprideis torosa and the introduction of marine species

Datos fenológicos de floración de algunas especies leñosas de la duna del Faro de Trafalgar (Barbate, Cádiz)

Datos fenológicos de floración de algunas especies leñosas de la duna del Faro de Trafalgar (Barbate, Cádiz). En este trabajo se ha estudiado la composición florística y algunos aspectos del comportamiento fenológico de floración de algunas especies del matorral leñoso existente en una duna fija costera del sur de la Península Ibérica. En la comunidad de vegetación leñosa de la duna del Faro de Trafalgar se desarrollan procesos de floración a lo largo de todo el año, observándose un máximo en primavera (Marzo-Abril), que corresponde a la época de mayor disponibilidad de recursos y climatología más favorable. En el verano se produce una regresión en la producción de flores, aunque sin llegar a desaparecer, hasta alcanzarse otro máximo en otoño, aunque de menor magnitud y duración que en primavera. En los meses invernales muchos matorrales presentan floración, hecho por otra parte frecuente en otras comunidades de matorrales mediterráneos

Ostracods as palaeoenvironmental tracers: evolution of the southern area of the Doñana National Park from the lower Pliocene to recent

El estudio de los materiales geológicos y las asociaciones de ostrácodos presentes en un testigo largo obtenido en el sur del Parque Nacional de Doñana (SO de España) permite inferir una evolución paleoambiental desde medios marinos someros (Plioceno Inferior) hasta un lagoon salobre (Pleistoceno Superior-Holoceno) y la implantación de sistemas eólicos (<1.900 años BP), con un estadio intermedio aluvial durante la mayor parte del Pleistoceno. En el Holoceno Superior, se detecta un evento tsunami- génico caracterizado por la erosión de sedimentos eólicos y su depósito sobre medios submarealesThe analysis of the geological units and the ostracod assemblages of a long core collected in the southern Doñana National Park (SW Spain) permits to deduce an evolution from shallow marine palaeoenvironments (Lower Pliocene) to a brackish lagoon (Upper Pleistocene-Holocene) and the deposit of aeolian sediments (<1900 yr BP), with an intermediate alluvial stage during the Pleistocene. In the Late Holocene, a tsunamigenic event was detected, with the erosion of aeolian sediments and a subsequent deposit on subtidal environment

Digital Wiretap Warrant: Improving the security of ETSI Lawful Interception

Lawful Interception (LI) of data communications is an essential tool for Law Enforcement Agencies (LEA) in order to investigate criminal activities carried out or coordinated by means of Internet. However, the ability to secretly monitor the activities of citizens also has a great impact on civil rights. Therefore, democratic societies must prevent abuse and ensure that LI is only employed in specific cases with justifiable grounds or a probable cause. Nowadays, in many countries each interception must be authorized by a wiretap warrant, usually issued by a judge. However, this wiretap warrant is merely an administrative document that should be checked by the network or service operator before enabling the monitoring of its customers, whose communications are later handed over to a LEA in plaintext. This paper proposes the idea of employing a Digital Wiretap Warrant (DWW), which further protects the civil liberties, security and privacy of LI by ensuring that monitoring devices can only be enabled with a valid DWW, and by encrypting the captured data so only the authorized LEA is able to decrypt those communications. Moreover, in the proposed DWW framework all digital evidence is securely time-stamped and signed, thus guaranteeing that it has not been tampered with, and that a proper chain of custody has been met. In particular this paper proposes how to apply the DWW concept to the lawful interception framework defined by the ETSI LI Technical Committee, and evaluates how the additional security mechanisms could impact the performance and storage costs of a LI platform.The work presented in this paper has been funded by the INDECT project (Ref 218086) of the 7th EU Framework Programme. The authors would also like to acknowledge the Spanish-funded CRAMnet (Grant no. TEC2012-38362-C03-01)

On Providing Metro Ethernet Services over Transparent WDM Optical Rings

The long list of benefits (especially cost and capacity) of Ethernet LANs has made the IEEE, the ITU-T, and the Metro Ethernet Forum define the requirements for taking Ethernet beyond the local area, toward the metropolitan region. In addition, the ever-increasing traffic demands of new applications and users can only be met by the huge bandwidth capacity provided by optical fibers. This work studies how to provide metro Ethernet services over transparent tunable-transmitter fixed-receiver WDM optical ring networks. A new adaptation layer of ME to WDM is proposed, and its benefits and drawbacks are studied. It is shown that such a transparent WDM ring network can be seen as a logical full-mesh topology by the upper ME layer, thus reducing to one the number of optical-electronic-optical conversions per unicast frame. Additionally, two different approaches are proposed in the case of broadcast/multicast traffic, since this may bring scalability difficulties in ring topologies.The work described in this article was carried out with the support of the Building the Future Optical Network in Europe (BONE) project, a Network of Excellence funded by the European Commission through the 7th ICT-Framework Programme. Additionally, the authors are thankful for the support of the T2C2 (grant TIN2008-06739C04-01) and MEDIANET (grant S2009/TIC-1468) projects for the development of this work.European Community's Seventh Framework ProgramPublicad

A Bloom Filter-Based Monitoring Station for a Lawful Interception Platform

Lawful Interception (LI) is a fundamental tool in today's Police investigations.Therefore, it is important to make it as quickly and securely as possible as well as a reasonable cost per suspect. This makes traffic capture in aggregation links quite attractive, although this implies high wirespeeds which require the use of specific hardware-based architectures. This paper proposes a novel Bloom Filter-based monitoring station architecture for efficient packet capture in aggregation links. With said Bloom filter, we filter out most of the packets in the link and capture only those belonging to lawful interception wiretaps. Next, we present an FPGA-based implementation of said architecture and obtain the maximum capture rate achievable by injecting traffic through four parallel Gigabit Ethernet lines. Finally, we identify the limitations of our current design and suggest the possibility of further extending it to higher wirespeeds.- Best Paper AwardThe work presented in this paper has been funded by the INDECT project grant number FP7-ICT-218086, and the Spanish CramNet project (grant no. TEC2012-38362-C03-01).European Community's Seventh Framework Progra

Study of a hybrid OCDMA-WDM segmented ring for metropolitan area networks

Proceeding of: 12th International Conference on High Performance Switching and Routing, Cartagena, Spain, July 4-6, 2011Optical Code Division Multiple Access (OCDMA) techniques have shown outstanding capabilities in the sharing of optical media, in particular in access networks. However, OCDMA systems may suffer from Multiple Access Interference (MAI) and other kinds of noise when many users access the shared media simultaneously, increasing the BER (Binary Error Rate) to unacceptable levels, that is, a situation at which all combined signals interfere and are lost. This work proposes a mixed OCDMA and Tunable Transmitter- Fixed Receiver (TT-FR) WDM and ring architecture at which the ring is split into small-size segments to limit the probability of MAI. Essentially, every segment in the ring has got two hub nodes (on the segment’s head and tail) which forwards inter-segment traffic to other hub nodes on dedicated home wavelengths, thus making use of WDM. The access media inside the segment is shared between the nodes by means of OCDMA, and code reuse is possible on different segments. Our performance analysis shows how to split a given ring into segments in order to minimise the BER due to multiple users accessing the network and allow for high bit-rates for a given traffic load. In addition, we analyse the possibility of introducing Forward Error Correction (FEC) at a moderate overhead cost to improve performance.The work described in this paper was carried out with the support of the BONE project (“Building the Future Optical Network in Europe”), a Network of Excellence funded by the European Commission through the 7th ICT-Framework Programme. Additionally, the authors would like to thank the support of the T2C2 Spanish project (under code TIN2008-06739-C04-01) and the Greencom UC3M-CAM project under code (CCG10-UC3M/TIC-5624).Publicad

Accelerated and natural carbonation of concretes with internal curing and shrinkage/viscosity modifiers

Abstract In many parts of the world, corrosion of reinforcing steel in concrete induced by carbonation of the concrete continues to be a major durability concern. This paper investigates the accelerated and natural carbonation resistance of a set of seven concretes, specifically evaluating the effects of internal curing and/or shrinkage/viscosity modifiers on carbonation resistance. In addition to five different ordinary portland cement (OPC) concretes, two concretes containing 20 % of a Class F fly ash as replacement for cement on a mass basis are also evaluated. For all seven concrete mixtures, a good correlation between accelerated (lab) and natural (field) measured carbonation coefficients is observed. Conversely, there is less correlation observed between the specimens’ carbonation resistance and their respective 28 days compressive strengths, with the mixtures containing the shrinkage/viscosity modifier specifically exhibiting an anomalous behavior of higher carbonation resistance at lower strength levels. For both the accelerated and natural exposures, the lowest carbonation coefficients are obtained for two mixtures, one containing the shrinkage/viscosity modifier added in the mixing water and the other containing a solution of the same admixture used to pre-wet fine lightweight aggregate. Additionally, the fly ash mixtures exhibited a significantly higher carbonation coefficient in both exposures than their corresponding OPC concretes

Geomorphology and recent geological evolution of Pan de Azúcar National Park coastal sector (northern Chile)

El análisis geomorfológico del borde costero del Parque Nacional de Pan de Azúcar (Chile) permite describir varias etapas en su evolución geológica reciente, principalmente controladas por el clima, las variaciones del nivel del mar y el alzamiento de la Cordillera de la Costa. Las primeras fases se refieren a los episodios de formación de tres generaciones de terrazas marinas, mientras que la última etapa involucra el Presente Interglacial, el establecimiento del nivel del mar actual, la formación del acantilado marino holoceno y el desarrollo de formas activas, con predominio del modelado eólico y fluvial/aluvial sobre este segmento litoral del sur del desierto de Atacama. Se describe, por primera vez en la zona, la formación de una terraza marina baja, aflorante próxima al nivel del mar actual, fechada en ~44000 años, asociada con la alta parada marina del MIS-3. Esta datación corrobora el inicio de un ciclo de levantamiento tectónico acelerado, con tasas de elevación ~1 m/ka, recientemente propuesto para el norte de Chile y que continuaría hasta el presenteThe geomorphological analysis of the coastal sector of Pan de Azúcar National Park (Chile) allows describing several stages in its recent geological evolution, mainly controlled by the climate, variations in the sea-level and the uplift of the Cordillera de la Costa. The first phases refer to the formation of three generations of marine terraces, while the last stage involves the Present Interglacial, the establishment of the current sea-level, the formation of the Holocene marine cliff and the development of active forms, with predominance of the eolian and fluvial/alluvial processes on this coastal segment of the southern Atacama Desert. For the first time, the occurrence of a low marine terrace that crops out near current sea-level is described in the study area. It has been dated in ~44000 years and associated with the MIS-3 highstand. This age corroborates the beginning of a cycle of accelerated tectonic uplift, with rates of ~ 1 m/ka, recently proposed for northern Chile that would continue until toda

Possible morpho-sedimentary evidence of the 1922 Atacama tsunami in the Pan de Azúcar National Park (northern Chile)

El gran terremoto de 1922 de Atacama es uno de los mayores eventos sísmicos del siglo XX en el límite de subducción entre las placas de Nazca y Sudamérica. Los principales daños provocados por el tsunami asociado ocurrieron en el litoral del norte de Chile. En la ciudad de Chañaral, una de la más afectadas, se alcanzó una cota máxima de inundación de 9 m sobre el nivel del mar y una inundación horizontal de 200 m. En este trabajo se aborda el estudio del registro geológico de este evento en el Parque Nacional Pan de Azúcar, 10 km al norte de esta ciudad portuaria, donde se describen formas erosivas y campos de bloques a cotas topográficas por encima de la zona de acción de temporales de invierno. Este trabajo resalta la necesidad de profundizar en el análisis de depósitos de grano grueso en sistemas costeros áridos para la identificación del registro de tsunamis, donde su potencial de preservación es bajo y sus evidencias tienden a aparecer enmascaradas en el paisaje litoralThe 1922 Atacama Earthquake is one of the largest megathrust earthquakes of the 20th century in the limit between the Nazca and South American plates. The main damages of the associated tsunami occurred in the coast of northern Chile. In the city of Chañaral, one of the most affected, a maximum flood height of 9 m above sea level and a horizontal inundation of 200 m were reached. The aim of this study is to analyze the geological record of this event in Pan de Azúcar National Park, 10 km north of this port city, where erosive forms and boulder fields have been described evidencing the wave action on the nearshore at heights above the winter storms. This work highlights the need to deepen in the study of the coarse-grain deposits in arid coastal systems to identify the record of tsunamis where their preservation potential is low, and their evidence is masked in the littoral landscap