Introducción

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Foraminíferos bentónicos del Cretácico Superior de la Cuenca Vascocantábrica, Norte de España

Se han estudiado los foraminíferos bentónicos del margen continental septentrional de la Placa Ibérica durante el Cretácico Superior (Cuenca Vascocantábrica). Un corte estratigráfi co realizado que abarca desde depósitos carbonatados de rampa interna con foraminíferos bentónicos de gran tamaño (columnas de Sobrón y Losavalle) hasta las alternancias margo-calizas de carácter hemipelágico (columnas de Villasana y Murguía) y las arcillas y margas pelágicas (columna de Galarreta-Gordoa y sondeo Urbasa-2) ha permitido estudiar la distribución de los foraminíferos bentónicos. La morfología funcional y el estilo de vida de los foraminíferos puede utilizarse para determinar su posición original en la rampa carbonatada y determinar tendencias de somerización y profundización hacia techo en las secuencias sedimentarias. El análisis secuencial de los depósitos de la rampa carbonatada del Cretácico Superior de la Cuenca Vascocantábrica se ha visto claramente mejorado utilizando los datos paleoecológicos de los foraminíferos bentónicos. La contrastación de la abundancia de foraminíferos bentónicos con el modelo de paleopendiente del Cretácico Superior ha permitido estimar el rango paleobatimétrico de vida de muchas especies de foraminíferos bentónicos en la cuenca Vascocantábrica

Foraminíferos bentónicos y paleoambientes del Jurásico Inferior y Medio de la zona occidental de la Cuenca Vasco-Cantábrica (norte de España)

Se estudian los foraminíferos bentónicos de edad Jurásico Inferior y Medio de la zona occidental de la Cuenca Vasco Cantábrica (secciones de Tudanca, Aguilar de Campoó y Barrios de Villadiegos). Se han reconocido cinco asociaciones de foraminíferos bentónicos, cada una de las cuales está relacionada con un paleoambiente trófi co específi co producido por condicionantes paleoceanográfi cos y por variaciones relativas del nivel del mar. La asociación Astacolus-Lingulina tiene lugar en depósitos transgresivos de alta energía del Sinemuriense inferior. La asociación Laevidentalina-Eoguttulina es característica de los depósitos transgresivos y bien oxigenados del Pliensbachiense. La asociación Ammobaculites-Reinholdella aparece en los depósitos anóxicos a poco oxigenados de edad Pliensbachiense, Toarciense y Calloviense. La asociación Saracenaria-Pseudolamarckina está relacionada con los depósitos de plataforma de baja energía de edad Aaleniense a Calloviense inferior. Y por último, la asociación Marginulina-Citharina caracteriza los sedimentos de alta energía del Aaleniense al Calloviense inferior. Los foraminíferos bentónicos muestran también variaciones en relación con la edad y con los cambios en el paleoambiente en función de los ciclos transgresivos-regresivos

Non-Adiabatic Electronic and Vibrational Ring-Opening Dynamics resolved with Attosecond Core-Level Spectroscopy

Non-adiabatic dynamics and conical intersections play a central role in the chemistry of most polyatomic molecules, ranging from isomerization to heterocyclic ring opening and avoided photo-damage of DNA. Studying the underpinning correlated dynamics of electronic and nuclear wave packets is a major challenge in real-time and, many times involves optically dark transient states. We show that attosecond core-level spectroscopy reveals the pathway dynamics of neutral furan across its conical intersections and dark states. Our method measures electronic-nuclear correlations to detect the dephasing of electronic coherence due to nuclear motion and identifies the ring-opened isomer as the dominant product. These results demonstrate the efficacy of attosecond core level spectroscopy as a potent method to investigate the real-time dynamics of photochemical reaction pathways in complex molecular systems

Infrared Laser Driven Double Proton Transfer. An Optimal Control Theory Study

Laser control of ultrafast double proton transfer is investigated for a two-dimensional model system describing stepwise and concerted transfer pathways. The pulse design has been done by employing optimal control theory in combination with the multiconfiguration time-dependent Hartree wave packet propagation. The obtained laser fields correspond to multiple pump-dump pulse sequences. Special emphasis is paid to the relative importance of stepwise and concerted transfer pathways for the driven wave packet and its dependence on the parameters of the model Hamiltonian as well as on the propagation time. While stepwise transfer is dominating in all cases considered, for high barrier systems concerted transfer proceeding via tunneling can make a contribution.Comment: 9 figure

Molecular isomerization and fragmentation of polyatomic molecules controlled by inner-valence recollision-ionization

Control over various fragmentation reactions of a series of polyatomic molecules (acetylene, ethylene, 1,3-butadiene) by the optical waveform of intense few-cycle laser pulses is demonstrated experimentally. We show both experimentally and theoretically that the responsible mechanism is inelastic ionization from inner-valence molecular orbitals by recolliding electron wave packets

Enhanced ionization of acetylene in intense laser pulses is due to energy upshift and field coupling of multiple orbitals

Synopsis We describe a new enhanced ionization mechanism for polyatomic molecules. It works via a significant energy up-shift of valence orbitals for stretched bonds and a strong concomitant increase in the coupling between multiple molecular orbitals

Pyrimidoquinazolinophenanthroline Opens Next Chapter in Design of Bridging Ligands for Artificial Photosynthesis **

The synthesis and detailed characterization of a new Ru polypyridine complex containing a heteroditopic bridging ligand with previously unexplored metal‐metal distances is presented. Due to the twisted geometry of the novel ligand, the resultant division of the ligand in two distinct subunits leads to steady state as well as excited state properties of the corresponding mononuclear Ru(II) polypyridine complex resembling those of prototype [Ru(bpy) 3 ] 2+ (bpy=2,2'‐bipyridine). The localization of the initially optically excited and the nature of the long‐lived excited states on the Ru‐facing ligand spheres is evaluated by resonance Raman and fs‐TA spectroscopy, respectively, and supported by DFT and TDDFT calculations. Coordination of a second metal (Zn or Rh) to the available bis‐pyrimidyl‐like coordination sphere strongly influences the frontier orbitals, apparent by, for example, luminescence quenching. Thus, the new bridging ligand motif offers electronic properties, which can be adjusted by the nature of the second metal center. Using the heterodinuclear Ru−Rh complex, visible light‐driven reduction of NAD + to NADH was achieved, highlighting the potential of this system for photocatalytic applications

Degradation of Bradykinin by Neutral Endopeptidase (EC 3.4.24.11) in Cultured Human Endothelial Cells

Peer Reviewe

Magnetic nanoparticles interact and pass an in vitro co-culture blood-placenta barrier model

Magnetic nanoparticles are interesting tools for biomedicine. Before application, critical prerequisites have to be fulfilled. An important issue is the contact and interaction with biological barriers such as the blood-placenta barrier. In order to study these processes in detail, suitable in vitro models are needed. For that purpose a blood-placenta barrier model based on the trophoblast-like cell line BeWo and primary placenta-derived pericytes was established. This model was characterized by molecular permeability, transepithelial electrical resistance and cell-cell-contact markers. Superparamagnetic iron oxide nanoparticles (SPIONs) with cationic, anionic or neutral surface charge were applied. The localization of the nanoparticles within the cells was illustrated by histochemistry. The time-dependent passage of the nanoparticles through the BeWo/pericyte barrier was measured by magnetic particle spectroscopy and atomic absorption spectroscopy. Cationically coated SPIONs exhibited the most extensive interaction with the BeWo cells and remained primarily in the BeWo/pericyte cell layer. In contrast, SPIONs with neutral and anionic surface charge were able to pass the cell layer to a higher extent and could be detected beyond the barrier after 24 h. This study showed that the mode of SPION interaction with and passage through the in vitro blood-placenta barrier model depends on the surface charge and the duration of treatmen