Glándulas de la sal en Maledictosuchus riclaensis (Metriorhynchidae, Thalattosuchia) del Calloviense de la Península Ibérica.

Maledictosuchus riclaensis es un metriorrínquido del Calloviense de la Península Ibérica. Los metriorrinquidos son un grupo de crocodilomorfos marinos que desarrollaron numerosas adaptaciones al medio marino pelágico. Además de adaptaciones morfológicas, desarrollaron glándulas de la sal hipertrofiadas, lo cual implica un alto grado de especialización. Estas glándulas se han descrito en dos especies de metriorrínquidos. Las glándulas de la sal se encargan de controlar el balance de la concentración de sales en el organismo. Al tratarse de tejidos blandos su preservación es muy poco frecuente. La tomo- grafía computarizada ha alcanzado en los últimos años gran importancia en la investigación paleontológica, ya que permite la visualización y estudio de las estructuras internas de los huesos y su digitalización en 3D, de una forma no invasiva y sin poner en riesgo al ejemplar. El holotipo de Maledictosuchus riclaensis consiste en un cráneo muy bien preservado y tres vértebras. Una tomografía computarizada del cráneo reveló la presencia de glándulas de la sal hipertrofiadas en este taxón

Ultra-fast relaxation of electrons in wide-gap dielectrics

Low-energy electrons scattered in the conduction band of a dielectric solid should behave like Bloch electrons and will interact with perturbations of the atomic lattice, i.e. with phonons. Thus the phonon-based description of low-energy scattering within an energy band structure of a solid bears certain advantages against common free-electron scattering mechanisms. Moreover, the inelastic scattering is described by the dielectric energy loss function. With these collective scattering models we have performed the simulation of excited electron relaxation and attenuation in the insulator SiO2. After excitation to a mean initial energy of several eV their energy relaxation occurs within a short time interval of 200 fs to full thermalization. There is a very rapid impact ionization cooling connected with cascading of electrons at the beginning during the first 10 fs, followed by much slower attenuation due to phonon losses in wide-gap dielectrics and insulators

Large-Mass Ultra-Low Noise Germanium Detectors: Performance and Applications in Neutrino and Astroparticle Physics

A new type of radiation detector, a p-type modified electrode germanium diode, is presented. The prototype displays, for the first time, a combination of features (mass, energy threshold and background expectation) required for a measurement of coherent neutrino-nucleus scattering in a nuclear reactor experiment. The device hybridizes the mass and energy resolution of a conventional HPGe coaxial gamma spectrometer with the low electronic noise and threshold of a small x-ray semiconductor detector, also displaying an intrinsic ability to distinguish multiple from single-site particle interactions. The present performance of the prototype and possible further improvements are discussed, as well as other applications for this new type of device in neutrino and astroparticle physics (double-beta decay, neutrino magnetic moment and WIMP searches).Comment: submitted to Phys. Rev.

Prevalence and Prognostic Influence of Peripheral Arterial Disease in Patients ≥40 Years Old Admitted into Hospital Following an Acute Coronary Event

AbstractObjectiveA significant proportion of patients with ischemic heart disease have associated peripheral arterial disease (PAD), but many are asymptomatic and this condition remains underdiagnosed. We aimed to study the prevalence of PAD in patients with an acute coronary syndrome (ACS) and to evaluate its influence in hospital clinical outcomes.MethodsThe PAMISCA register is a prospective, multicenter study involving patients ≥40 years old with ACS admitted to selected Spanish hospitals. All patients had their ankle-brachial index (ABI) measured between days 3 and 7 after the ischemic event.Results1410 ACS patients (71.4% male) were included. PAD determined by ABI was documented in 561 patients (39.8%). Factors independently related to PAD were age (OR: 1.04; 95% CI: 1.03–1.06; p<0.001), smoking (OR: 1.88; 95% CI: 1.41–2.49; p<0.0001), diabetes (OR: 1.30; 95% CI: 1.02–1.65; p<0.05), previous cardiac disease (OR: 1.54; 95% CI: 1.22–1.95; p<0.001) and previous cerebrovascular disease (OR: 1.90; 95% CI: 1.28–2.80; p<0.001). Following the ACS, an ABI≤0.90 was associated with increased cardiovascular mortality (OR: 5.45; 95% CI: 1.16–25.59; p<0.05) and a higher risk of cardiovascular complications.ConclusionThe prevalence of PAD in patients ≥40 years presenting with ACS is high and it is associated with increased cardiovascular risk

Algorithm and performance of a clinical IMRT beam-angle optimization system

This paper describes the algorithm and examines the performance of an IMRT beam-angle optimization (BAO) system. In this algorithm successive sets of beam angles are selected from a set of predefined directions using a fast simulated annealing (FSA) algorithm. An IMRT beam-profile optimization is performed on each generated set of beams. The IMRT optimization is accelerated by using a fast dose calculation method that utilizes a precomputed dose kernel. A compact kernel is constructed for each of the predefined beams prior to starting the FSA algorithm. The IMRT optimizations during the BAO are then performed using these kernels in a fast dose calculation engine. This technique allows the IMRT optimization to be performed more than two orders of magnitude faster than a similar optimization that uses a convolution dose calculation engine.Comment: Final version that appeared in Phys. Med. Biol. 48 (2003) 3191-3212. Original EPS figures have been converted to PNG files due to size limi

An overview on the natural enemies of Rhynchophorus palm weevils, with focus on R. ferrugineus.

Rhynchophorus palm weevils are large insects belonging to the family Dryophthoridae. All Rhynchophorus species are polyphagous and have a similar life history but some are major pests because of the serious economic damage they cause, in particular to several species of the family Arecaceae. Here we review the natural enemies of Rhynchophorus species in both their native and introduced regions of the world, to assess the possibility of biological control of this taxon. Moreover, particular attention is paid to the well-studied and harmful species Rhynchophorus ferrugineus, about which more information is available, and to its natural enemies in the Mediterranean region, because the impact of this pest in this recently colonized area is particularly remarkable and also the recent trend in species management is looking for indigenous natural enemies. More than 50 natural enemies have been reported to attack Rhynchophorus species, even if most of them are associated to R. ferrugineus (Olivier), highlighting the lack of information on the other species of the genus. Pros and cons of all the biological control agents are then discussed: among the considered organisms, fungi are noteworthy to be considered for inclusion in integrated pest management programs. Overall, our overview underlines the need to increase knowledge on natural enemies of all the species of the genus Rhynchophorus, to isolate more virulent strains and to determine the optimum conditions for the actions of the biocontrol agents

Studies on the coastal ecology and management of the Nabq Protected Area, South Sinai, Egypt.

The dopaminergic system provides the basis for the interaction between motivation and cognition. It is triggered by the possibility of obtaining rewards to initiate the neurobehavioral adaptations necessary to achieve them by directing the information from motivational circuits to cognitive and action circuits. In drug addiction, the altered dopamine (DA) modulation of the meso-cortico-limbic reward circuitry, such as the prefrontal cortex (PFC), underlies the disproportionate motivational value of drug use at the expense of other nondrug reinforcers and the user''s loss of control over his/her drug intake. We examine how the magnitude of the reward affects goal-directed processes in healthy control (HC) subjects and abstinent cocaine dependent (ACD) patients by using functional magnetic resonance imaging (fMRI) during a counting Stroop task with blocked levels of monetary incentives of different magnitudes (€0, €0.01, €0.5, €1 or €1.5). Our results showed that increasing reward magnitude enhances (1) performance facilitation in both groups; (2) left dorsolateral prefrontal cortex (DLPFC) activity in HC and left superior occipital cortex activity in ACD; and (3) left DLPFC and left putamen connectivity in ACD compared to HC. Moreover, we observed that (4) dorsal striatal and pallidum activity was associated with craving and addiction severity during the parametric increases in the monetary reward. In conclusion, the brain response to gradients in monetary value was different in HC and ACD, but both groups showed improved task performance due to the possibility of obtaining greater monetary rewards

Mutational Analysis of the Cyanobacterial Nitrogen Regulator PipX

PipX provides a functional link between the cyanobacterial global transcriptional regulator NtcA and the signal transduction protein PII, a protein found in all three domains of life as integrators of signals of the nitrogen and carbon balance. PipX, which is toxic in the absence of PII, can form alternative complexes with NtcA and PII and these interactions are respectively stimulated and inhibited by 2-oxoglutarate, providing a mechanism by which PII can modulate expression at the NtcA regulon. Structural information on PipX-NtcA complexes suggests that PipX coactivates NtcA controlled genes by stabilizing the active conformation of NtcA bound to 2-oxoglutarate and by possibly helping recruit RNA polymerase. To get insights into PipX functions, we perform here a mutational analysis of pipX informed by the structures of PipX-PII and PipX-NtcA complexes and evaluate the impact of point mutations on toxicity and gene expression. Two amino acid substitutions (Y32A and E4A) were of particular interest, since they increased PipX toxicity and activated NtcA dependent genes in vivo at lower 2-oxoglutarate levels than wild type PipX. While both mutations impaired complex formation with PII, only Y32A had a negative impact on PipX-NtcA interactions

Molecular features of new Peach Latent Mosaic Viroid variants suggest that recombination may have contributed to the evolution of this infectious RNA.

peer reviewe

Magnetic PiezoBOTs: a microrobotic approach for targeted amyloid protein dissociation

Piezoelectric nanomaterials have become increasingly popular in the field of biomedical applications due to their high biocompatibility and ultrasound-mediated piezocatalytic properties. In addition, the ability of these nanomaterials to disaggregate amyloid proteins, which are responsible for a range of diseases resulting from the accumulation of these proteins in body tissues and organs, has recently gained considerable attention. However, the use of nanoparticles in biomedicine poses significant challenges, including targeting and uncontrolled aggregation. To address these limitations, our study proposes to load these functional nanomaterials on a multifunctional mobile microrobot This microrobot is designed by coating magnetic and piezoelectric barium titanate nanoparticles on helical biotemplates, allowing for the combination of magnetic navigation and ultrasound-mediated piezoelectric effects to target amyloid disaggregation. Our findings demonstrate that acoustically actuated PiezoBOTs can effectively reduce the size of aggregated amyloid proteins by over 80% in less than 10 minutes by shortening and dissociating constituent amyloid fibrils. Moreover, the PiezoBOTs can be easily magnetically manipulated to actuate the piezocatalytic nanoparticles to specific amyloidosis-affected tissues or organs, minimizing side effects. These biocompatible PiezoBOTs offer a promising non-invasive therapeutic approach for amyloidosis diseases by targeting and breaking down protein aggregates at specific organ or tissue sites