Formic Acid Ionization and Fragmentation by Multiphoton Absorption

Multiphoton absorption is an intensity dependent nonlinear effect related to the excitation of virtual intermediate states. In the present work, multiphoton ionization and dissociation of the formic acid molecule (HCOOH) by the interaction with photons from 532 Nd: YAG laser at different intensities are discussed, using different carrier gases. The induced fragmentation-ionization patterns show up to 17 fragments and dissociation channels are proposed. Some evidence of small clusters formation and conformational memory from the ratio of the detected products, CO+ and CO2+, on the light of the available results, it is possible to conclude that they arise from trans and cis formic acid. Our results are compared with those obtained in other laboratories under different experimental conditions, some of them show only partial agreement and differences are discussed. Following the Keldysh description it is possible, from our experimental parameters, characterize our results, in the multiphoton absorption regime

Interés terapéutico de las estatinas en el tratamiento de la aterosclerosis

Los inhibidores de la HMG-Co A reductasa o estatinas, son fármacos muy utilizados en el tratamiento de lahipercolesterolemia, ya que consiguen disminuir la concentración plamática de lipoproteína de baja densidad (LDL)regulando la síntesis endógena de colesterol y por tanto, de receptores para LDL.Recientemente se ha comprobado como el tratamiento prolongado con estos fármacos disminuyen la mortalidad ymorbilidad cardiovascular. Este fenómeno puede explicarse por los efectos beneficiosos directos de las estatinas enel desarrollo de la placa de ateroma. Las estatinas disminuyen la proliferación y migración de células de musculaturalisa vascular e inducen apoptosis de estas células. También previenen la oxidación de LDL y la formación de célulasespumosas, reducen la respuesta inflamatoria asociada a la aterosclerosis, normalizan los fenómenos de coagulacióny fibrinolisis y por último mejoran significativamente la función endotelial. Todas estas propiedades parecen estarmediadas compuestos isoprenoides intermediarios de la ruta metabólica de la HMG-Co A reductasa, y son independientesde la concentración de colesterol en el medio.Por tanto, las estatinas también podrían ser utilizadas en enfermedades asociadas a disfunción endotelial independientementede las cifras analíticas de LDL, tal y como sucede en la hipertensión

Therapeutical interest of statins in the treatment of atherosclerosis

Los inhibidores de la HMG-Co A reductasa o estatinas, son fármacos muy utilizados en el tratamiento de la hipercolesterolemia, ya que consiguen disminuir la concentración plamática de lipoproteína de baja densidad (LDL) regulando la síntesis endógena de colesterol y por tanto, de receptores para LDL. Recientemente se ha comprobado como el tratamiento prolongado con estos fármacos disminuyen la mortalidad y morbilidad cardiovascular. Este fenómeno puede explicarse por los efectos beneficiosos directos de las estatinas en el desarrollo de la placa de ateroma. Las estatinas disminuyen la proliferación y migración de células de musculatura lisa vascular e inducen apoptosis de estas células. También previenen la oxidación de LDL y la formación de células espumosas, reducen la respuesta inflamatoria asociada a la aterosclerosis, normalizan los fenómenos de coagulación y fibrinolisis y por último mejoran significativamente la función endotelial. Todas estas propiedades parecen estar mediadas compuestos isoprenoides intermediarios de la ruta metabólica de la HMG-Co A reductasa, y son independientes de la concentración de colesterol en el medio. Por tanto, las estatinas también podrían ser utilizadas en enfermedades asociadas a disfunción endotelial independientemente de las cifras analíticas de LDL, tal y como sucede en la hipertensión.HMG-Co A reductase inhibitors or statins, are widely used drugs in the treatment of hypercholesterolemia. They lower plasmatic concentration of low density lipoprotein (LDL) by regulating cholesterol synthesis and consequently synthesis of LDL receptors. Chronic treatment with these drugs has recently shown to be able to reduce cardiovascular-related morbidity and mortality. This fact could be explained by a direct benefic effect of statins in development of atherosclerotic plaque. Statins reduce vascular smooth muscle cell proliferation and migration , as well as they induce apoptosis of these cells. They also prevent LDL oxidation and foam cell formation, reducing inflammatory response associated to atherosclerosis, normalising coagulation and fibronolysis and improving endothelial function. All these properties seem to be mediated by intermediary isoprenoid compounds from HMG-Co A reductase metabolic pathway and do not depend of cholesterol concentration in the medium. Thus, statins could also be used in the treatment of some diseases associated to endothelial disfunction, independently of analytical LDL values, like hypertension

Search of dark-matter axions in the microwave frequency range with full-wave modal techniques

Axions, originally proposed to solve the strong Charge-Parity problem of Quantum Chromo-Dynamics theory, emerge now as leading candidates of dark matter. In fact, the search of dark-matter axions in the microwave frequency range has been developed by different research groups during the last twenty years. In this demanding scenario, several microwave passive components (haloscopes) have been designed and fabricated for such axions detection based on the use of cavities and multi-cavities. From an electromagnetic point of view, comercial software (ANSFT HFSS, CST MICROWAVE STUDIO, etc ) has been employed for the design of different kind of haloscopes. In this work we propose to use the BI-RME 3D method (Boundary Integral – Resonant Mode Expansion) as an alternative to analyze the axion-photon coupling existing within an haloscope. This full-wave modal technique has provided interesting wide-band results for the design of new haloscopes

Performance measurement of essential public health functions in three municipalities, Antioquia-Colombia, 2011

ABSTRACT: To measure the performance of the Essential Public Health Functions (ephf) in three municipalities from the Penderisco area of Southwestern Antioquia (a zone encompassing three municipalities: Betulia, Concordia, and Salgar) in 2011. Methodology: we conducted a cross-sectional descriptive study in three municipalities. To this end, we adapted the instrument for measuring ephf for use in Colombia. The instrument was developed by the paho, and we implemented its adapted version locally. The instrument was adjusted to the skills and fields of action of the municipal authorities, the questions that were not relevant for the local context were removed, and the formulas for generating scores and indicators were re-calculated. The instrument was applied to a group of experts in each municipality. Results: in the Penderisco zone, three functions had optimal performance: ephf1, ephf4, ephf2. Additionally, the functions labeled ephf3, ephf5, ephf6, ephf7, ephf8, ephf9, and ephf11 had above average performance. ephf10, in turn, showed minimum performance. Two indicators of development of capacity and infrastructure for public health were classified as weaknesses, namely: knowledge, skills, and mechanisms to review, refine and enforce the regulatory framework and development of institutional research capacity. This is consistent in the three municipalities. Conclusions: In spite of the efforts made by countries to improve the performance of the essential public health functions, development is still budding; the same scenario is seen in the studied municipalities. Few functions had optimal performance and were considered strengths and capacity development and the infrastructure for supporting the development of essential public health functions are weak.RESUMEN: Medir el desempeño de las Funciones Esenciales en Salud Pública (fesp) en tres municipios que corresponden a la zona Penderisco del suroeste antioqueño (Concordia, Betulia y Salgar) en 2011. Metodología: se realizó un estudio descriptivo transversal en los tres municipios. Se adaptó el instrumento de medición de las fesp en el ámbito nacional, elaborado por la ops para aplicarlo localmente, se ajustó a las competencias y campos de acción de las autoridades municipales, se suprimieron preguntas no pertinentes para el nivel y se recalcularon las fórmulas que generaban el puntaje y los indicadores. El instrumento se aplicó a un grupo de expertos en cada municipio. Resultados: en la zona Penderisco, se encontraron tres funciones fesp1, fesp2 y fesp4 con desempeño óptimo. Las fesp3, fesp5, fesp6, fesp7, fesp8, fesp9 y fesp11 con desempeño medio superior y la fesp10 un desempeño mínimo. Dos indicadores de desarrollo de capacidades e infraestructura para la salud pública, fueron clasificados como debilidades, coincidente en los tres municipios: conocimientos, habilidades y mecanismos para revisar, perfeccionar y hacer cumplir el marco regulatorio y el desarrollo de la capacidad institucional de investigación. Conclusiones: a pesar de los esfuerzos realizados por los países para mejorar el desempeño de las fesp, el desarrollo es incipiente con algunas excepciones, este mismo esquema se refleja en los municipios estudiados. Pocas funciones están clasificadas en desempeño óptimo y como fortalezas. El desarrollo de capacidades e infraestructura para soportar el desarrollo de las fesp es débil

Valorización de un aceite residual de alta acidez generado en las industrias de reciclaje de aceites de desecho de cocinas

A sludge fraction is obtained from the industries which recycle cooking oil and this sludge contains a large amount of oil with an extremely high acidity ( > 60%). In this work, we propose a scheme for methyl ester production from this residual oil consisting of the esterification of the free fatty acids followed by the transesterification of the remaining triglycerides. Esterifications were carried out with different methanol:oil molar ratios, and various catalysts in different weight ratios. The results revealed that homogeneous catalysts produced higher yields than heterogeneous ones in the esterification reaction. With the aim of improving the process, a previous triglyceride hydrolysis was assayed using lipases from Candida rugosa. Finally, the 3-stage process was performed under the most favorable conditions for each stage obtaining 84% wt. fatty acid methyl esters, which shows the potential of this residual oil as a source of biodiesel.En las industrias de recogida y reciclado de aceites de fritura usados se obtiene una fracción de lodos que contiene un gran porcentaje de aceite con un extremadamente alto índice de acidez ( > 60%). En este trabajo proponemos un esquema de producción de ésteres metílicos basado en la esterificación de los ácidos grasos libres seguida de la transesterificación de los triglicéridos remanentes. Las esterificaciones se llevaron a cabo usando diferentes relaciones molares metanol:aceite y diversos catalizadores en diferentes concentraciones en peso. Los resultados ilustraron que los catalizadores homogéneos alcanzaron mayores rendimientos en la esterificación que los catalizadores heterogéneos. Para mejorar el proceso, se probó una hidrólisis previa con lipasas de Candida rugosa. Finalmente, se llevó a cabo el proceso con las 3 etapas, en las condiciones más favorables de cada una de ellas, obteniendo un 84% en peso de ésteres metílicos, lo que muestra el potencial de este aceite residual como fuente de biodiésel

2D magnetic domain wall ratchet: The limit of submicrometric holes

The study of ratchet and crossed-ratchet effects in magnetic domain wall motion through 2D arrays of asymmetric holes is extended in this article to the submicrometric limit in hole size (small size regime). Therefore, the gap has been closed between the 2D ratchets in the range of tens-of-micrometers (large size regime) and the small size regime 1D ratchets based on nanowires. The combination of Kerr microscopy, X-ray PhotoEmission Electron Microscopy and micromagnetic simulations has allowed a full magnetic characterisation of both the domain wall (DW) propagation process over the whole array and the local DW morphology and pinning at the holes. It is found that the 2D small size limit is driven by the interplay between DW elasticity and half vortex propagation along hole edges: as hole size becomes comparable to DW width, flat DW propagation modes are favoured over kinked DW propagation due to an enhancement of DW stiffness, and pinned DW segments adopt asymmetric configurations related with Néel DW chirality. Nevertheless, both ratchet and crossed-ratchet effects have been experimentally found, and we propose a new ratchet/inverted-ratchet effect in the submicrometric range driven by magnetic fields and electrical currents respectively

Origin, genomic diversity and microevolution of the clostridium difficile b1/nap1/rt027/st01 strain in costa rica, chile, honduras and mexico

Indexación: Scopus.Clostridium difficile B1/NAP1/RT027/ST01 has been responsible for outbreaks of antibiotic-associated diarrhoea in clinical settings worldwide and is associated with severe disease presentations and increased mortality rates. Two fluoroquinolone-resistant (FQR) lineages of the epidemic B1/NAP1/RT027/ST01 strain emerged in the USA in the early 1990s and disseminated trans continentally (FQR1 and FQR2). However, it is unclear when and from where they entered Latin America (LA) and whether isolates from LA exhibit unique genomic features when compared to B1/NAP1/RT027/ST01 isolates from other regions of the world. To answer the first issue we compared whole-genome sequences (WGS) of 25 clinical isolates typed as NAP1, RT027 or ST01 in Costa Rica (n=16), Chile (n=5), Honduras (n=3) and Mexico (n=1) to WGS of 129 global isolates from the same genotype using Bayesian phylogenomics. The second question was addressed through a detailed analysis of the number and type of mutations of the LA isolates and their mobile resistome. All but two B1/NAP1/RT027/ST01 isolates from LA belong to the FQR2 lineage (n=23, 92 %), confirming its widespread distribution. As indicated by analysis of a dataset composed of 154 WGS, the B1/NAP1/RT027/ST01 strain was introduced into the four LA countries analysed between 1998 and 2005 from North America (twice) and Europe (at least four times). These events occurred soon after the emergence of the FQR lineages and more than one decade before the first report of the detection of the B1/NAP1/RT027/ST01 in LA. A total of 552 SNPs were identified across all genomes examined (3.8–4.3 Mb) in pairwise comparisons to the R20291 reference genome. Moreover, pairwise SNP distances were among the smallest distances determined in this species so far (0 to 55). Despite this high level of genomic conservation, 39 unique SNPs (7 %) in genes that play roles in the infection process (i.e. slpA) or antibiotic resistance (i.e. rpoB, fusA) distinguished the LA isolates. In addition, isolates from Chile, Honduras and Mexico had twice as many antibiotic resistance genes (ARGs, n=4) than related isolates from other regions. Their unique set of ARGs includes a cfr-like gene and tetM, which were found as part of putative mobile genetic elements whose sequences resemble undescribed integrative and conjugative elements. These results show multiple, independent introductions of B1/NAP1/RT027/ ST01 isolates from the FQR1 and FQR2 lineages from different geographical sources into LA and a rather rapid accumulation of distinct mutations and acquired ARG by the LA isolates.https://www.microbiologyresearch.org/content/journal/mgen/10.1099/mgen.0.00035