93 research outputs found
Magneto-optical effects in interacting localized and propagating surface plasmon modes
We report that the effect of an external magnetic field on the propagation of surface plasmons can be effectively modified through the coupling between localized (LSP) and propagating (SPP) surface plasmons. When these plasmon modes do not interact, the main effect of the magnetic field is a modification of the wavevector of the SPP mode, leaving the LSP virtually unaffected. Once both modes start to interact, there is a strong variation of the magnetic field induced modification of the SPP dispersion curve and, simultaneously, the LSP mode becomes sensitive to the magnetic field.This work was supported by the EU (NMP3-SL- 2008-214107-Nanomagma), the Spanish MICINN (“MAGPLAS” MAT2008-06765-C02-01/NAN and “FUNCOAT” CONSOLIDER INGENIO 2010 CSD2008-00023), the Comunidad de Madrid (“NANOBIOMAGNET” S2009/MAT-1726 and “MICROSERES-CM” S2009/TIC-1476), and CSIC (“CRIMAFOT” PIF08-016-4). We thank A. Cebollada and J. M. García-Martín for growing and characterizing the Au/Co/Au trilayers and reading this manuscript, and R. Quidant and G.Badenes for fruitful discussions.Peer reviewe
The ongoing volcanic eruption of El Hierro, Canary Islands
El Hierro, the youngest of the Canary Islands (Spain), is no stranger to hazards associated with volcanic activity or to efforts to minimize the effects of these hazards on local communities. As early as 1793, administrative records of El Hierro indicate that a swarm of earthquakes was felt by locals; fearing a greater volcanic catastrophe, the first evacuation plan of an entire island in the history of the Canaries was prepared. The 1793 eruption was probably submarine with no appreciable consequences other than that the earthquakes were felt [Carracedo, 2008]; over the next roughly 215 years the island was seismically quiet. Yet seismic and volcanic activity are expected on this youngest Canary Island due to its being directly above the presumed location of the Canary Island hot spot, a mantle plume that feeds upwelling magma just under the surface, similar to the Hawaiian Islands. Because of this known geologic activity, the Spanish Instituto Geogrfco Nacional (IGN) has managed geophysical monitoring of the island since the beginning of the 1990s.Peer Reviewe
The 2011 submarine volcanic eruption in El Hierro (Canary Islands)
Forty years after the Teneguía Volcano (La Palma, 1971), a submarine eruption took place off the town of La Restinga, south of El Hierro, the smallest and youngest island of the Canarian Archipelago. Precursors allowed an early detection of the event and its approximate location, suggesting it was submarine. Uncertainties derived from insufficient scientific information available to the authorities during the eruption, leading to disproportionate civil protection measures, which had an impact on the island's economy-based primarily on tourism-while residents experienced extra fear and distress. © 2012 Blackwell Publishing Ltd, The Geologists' Association & The Geological Society of London.Peer Reviewe
The 2011 submarine volcanic eruption in El Hierro (Canary Islands)
Forty years after the Teneguía Volcano (La Palma, 1971), a submarine eruption took place off the town of La Restinga, south of El Hierro, the smallest and youngest island of the Canarian Archipelago. Precursors allowed an early detection of the event and its approximate location, suggesting it was submarine. Uncertainties derived from insufficient scientific information available to the authorities during the eruption, leading to disproportionate civil protection measures, which had an impact on the island's economy-based primarily on tourism-while residents experienced extra fear and distress. © 2012 Blackwell Publishing Ltd, The Geologists' Association & The Geological Society of London.Peer Reviewe
Tunable magneto-photonic response of nickel nanostructures
In this letter, we present both experimental and numerical studies of the magneto-optical (MO) properties of nickel infiltrated opals. Ni can show interesting MO properties that can be controlled by nanostructuration through colloidal crystals templating. Nanostructuration allows the coupling of light to surface plasmon modes of Ni, and a clear dependence of the MO response as a function of the structural parameters of the template has been observed. This dependence can be used in future tunable devices such as switchers or MO modulators. © 2011 American Institute of Physics.This work has been partially supported by EU FP7 (NoE Nanophotonics 4 Energy Grant No. 248855 and NMP3-SL-2008-214107-Nanomagma); the CSIC PIF08-016, the Spanish MICINN (CSD2007-0046-Nanolight.es, CSD2008-00023-Funcoat, MAT2009-07841-GLUSFA, MAT2008-06765-C02-01/NAN-MAGPLAS) and Comunidad de Madrid (S2009/MAT-1756-PHAMA and S2009/TIC–1476- MICROSERES).Peer Reviewe
Identification of an Elusive Spliceogenic MYBPC3 Variant in an Otherwise Genotype-Negative Hypertrophic Cardiomyopathy Pedigree
Case report[Abstract] The finding of a genotype-negative hypertrophic cardiomyopathy (HCM) pedigree with several affected members indicating a familial origin of the disease has driven this study to discover causative gene variants. Genetic testing of the proband and subsequent family screening revealed the presence of a rare variant in the MYBPC3 gene, c.3331-26T>G in intron 30, with evidence supporting cosegregation with the disease in the family. An analysis of potential splice-altering activity using several splicing algorithms consistently yielded low scores. Minigene expression analysis at the mRNA and protein levels revealed that c.3331-26T>G is a spliceogenic variant with major splice-altering activity leading to undetectable levels of properly spliced transcripts or the corresponding protein. Minigene and patient mRNA analyses indicated that this variant induces complete and partial retention of intron 30, which was expected to lead to haploinsufficiency in carrier patients. As most spliceogenic MYBPC3 variants, c.3331-26T>G appears to be non-recurrent, since it was identified in only two additional unrelated probands in our large HCM cohort. In fact, the frequency analysis of 46 known splice-altering MYBPC3 intronic nucleotide substitutions in our HCM cohort revealed 9 recurrent and 16 non-recurrent variants present in a few probands (≤ 4), while 21 were not detected. The identification of non-recurrent elusive MYBPC3 spliceogenic variants that escape detection by in silico algorithms represents a challenge for genetic diagnosis of HCM and contributes to solving a fraction of genotype-negative HCM cases.This article was funded by Secretaria Xeral de Investigación e Desenvolvemento, Xunta de Galicia, GRC ED431C 2018/38. Open access funding provided by Health in CodeXunta de Galicia; ED431C 2018/3
Biochemical and structural characterization of a novel thermophilic esterase EstD11 provide catalytic insights for the HSL family
[Abstract]: A novel esterase, EstD11, has been discovered in a hot spring metagenomic library. It is a thermophilic and thermostable esterase with an optimum temperature of 60 C. A detailed substrate preference analysis of EstD11 was done using a library of chromogenic ester substrate that revealed the broad substrate specificity of EstD11 with significant measurable activity against 16 substrates with varied chain length, steric hindrance, aromaticity and flexibility of the linker between the carboxyl and the alcohol moiety of the ester. The tridimensional structures of EstD11 and the inactive mutant have been determined at atomic resolutions. Structural and bioinformatic analysis, confirm that EstD11 belongs to the family IV, the hormone-sensitive lipase (HSL) family, from the α/β-hydrolase superfamily. The canonical a/b hydrolase domain is completed by a cap domain, composed by two subdomains that can unmask of the active site to allow the substrate to enter. Eight crystallographic complexes were solved with different substrates and reaction products that allowed identification of the hot-spots in the active site underlying the specificity of the protein. Crystallization and/or incubation of EstD11 at high temperature provided unique information on cap dynamics and a first glimpse of enzymatic activity in vivo. Very interestingly, we have discovered a unique Met zipper lining the active site and the cap domains that could be essential in pivotal aspects as thermo-stability and substrate promiscuity in EstD11Ministerio de Ciencia e Innovación; BFU2017-90030-
Oral particle uptake and organ targeting drives the activity of amphotericin B nanoparticles
There are very few drug delivery
systems that target key organs
via the oral route, as oral delivery advances normally address gastrointestinal
drug dissolution, permeation, and stability. Here we introduce a nanomedicine
in which nanoparticles, while also protecting the drug from gastric
degradation, are taken up by the gastrointestinal epithelia and transported
to the lung, liver, and spleen, thus selectively enhancing drug bioavailability
in these target organs and diminishing kidney exposure (relevant to
nephrotoxic drugs). Our work demonstrates, for the first time, that
oral particle uptake and translocation to specific organs may be used
to achieve a beneficial therapeutic response. We have illustrated
this using amphotericin B, a nephrotoxic drug encapsulated within <i>N</i>-palmitoyl-<i>N</i>-methyl-<i>N</i>,<i>N</i>-dimethyl-<i>N</i>,<i>N</i>,<i>N</i>-trimethyl-6-<i>O</i>-glycol chitosan
(GCPQ) nanoparticles, and have evidenced our approach in three separate
disease states (visceral leishmaniasis, candidiasis, and aspergillosis)
using industry standard models of the disease in small animals. The
oral bioavailability of AmB-GCPQ nanoparticles is 24%. In all disease
models, AmB-GCPQ nanoparticles show comparable efficacy to parenteral
liposomal AmB (AmBisome). Our work thus paves the way for others to
use nanoparticles to achieve a specific targeted delivery of drug
to key organs via the oral route. This is especially important for
drugs with a narrow therapeutic index
Bouncing Spallation Bombs During the 2021 La Palma Eruption, Canary Islands, Spain
Incandescent pyroclasts of more than 64 mm in diameter erupted from active volcanoes are known as bombs and pose a significant hazard to life and infrastructure. Volcanic ballistic projectile hazard assessment normally considers fall as the main transport process, estimating its intensity from bomb location and impact cratering. We describe ballistically ejected bombs observed during the late October 2021 episode of eruption at La Palma (Canary Islands) that additionally travelled downhill by rolling and bouncing on the steep tephra-dominated cone. These bouncing bombs travelled for distances >1 km beyond their initial impact sites, increasing total travel distance by as much as 100%. They left multiple impact craters on their travel path and frequently spalled incandescent fragments on impact with substrate, leading to significant fire hazard for partially buried trees and structures far beyond the range of ballistic transport. We term these phenomena as bouncing spallation bombs. The official exclusion zone encompassed this hazard at La Palma, but elsewhere bouncing spallation bombs ought to be accounted for in risk assessment, necessitating awareness of an increased hazard footprint on steep-sided volcanoes with ballistic activity
The 2021 eruption of the Cumbre Vieja volcanic ridge on La Palma, Canary Islands
Almost exactly half a century after the eruption of the Teneguía Volcano on La Palma (26 October to 28 November 1971), a new eruption occurred on the island and lasted for 85 days from 19 September until 13 December 2021. This new eruption opened a volcanic vent complex on the western flank of the Cumbre Vieja rift zone, the N-S elongated polygenetic volcanic ridge that has developed on La Palma over the last c. 125 ka. The Cumbre Vieja ridge is the volcanically active region of the island and the most active one of the Canary Islands, hosting half of all the historically recorded eruptive events in the archipelago. The 2021 La Palma eruption has seen no direct loss of human life, thanks to efficient early detection and sensible management of the volcanic crisis by the authorities, but more than 2800 buildings and almost 1000 hectares of plantations and farmland were affected by lava flows and pyroclastic deposits. Satellite surveillance enabled accurate mapping of the progressive buildup of the extensive and complex basaltic lava field, which together with monitoring of gas emissions informed the timely evacuation of local populations from affected areas. Lava flows that reached the sea constructed an extensive system of lava deltas and platforms, similar to events during earlier historical eruptions such as in 1712, 1949 and 1971. Long-term challenges in the aftermath of the eruption include protection of drainage systems from potential redistribution of tephra during high rainfall events, the use of the large surplus quantities of ash in reconstruction of buildings and in agriculture, and the crucial concerns of where and how rebuilding should and could occur in the aftermath of the eruption. Finally, there remain strong financial concerns over insurance for properties consumed or damaged by the eruption in the light of future volcanic hazards from the Cumbre Vieja volcanic ridge.Peer reviewe
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