Tratado de re militari hecho a manera de dialogo... entre... Don Gonçalo Fernandez de Cordoua... y Don Pedro Manrrique de Lara...

Copia digital. Madrid : Ministerio de Cultura. Subdirección General de Coordinación Bibliotecaria, 2009Encabezamiento tomado de Peeters Fontainas, II, 1157Marca en port. y 2H\b4\s vSign.: A-Z\p4\s, 2A-2H\p4\sError de fol. a partir de h. 35Port. con orla tipLas h. pleg. son cuadros con formaciones de tropas hechos con letras y pequeños grabs. xi

The Newman-Janis Algorithm, Rotating Solutions and Einstein-Born-Infeld Black Holes

A new metric is obtained by applying a complex coordinate trans- formation to the static metric of the self-gravitating Born-Infeld monopole. The behaviour of the new metric is typical of a rotating charged source, but this source is not a spherically symmetric Born-Infeld monopole with rotation. We show that the structure of the energy-momentum tensor obtained with this new metric does not correspond to the typical structure of the energy momentum tensor of Einstein-Born-Infeld theory induced by a rotating spherically symmetric source. This also show, that the complex coordinate transformations have the interpretation given by Newman and Janis only in space-time solutions with linear sources

Dietary antioxidant intake is inversely associated with 2,3-dinor oxylipin metabolites, the major excreted oxylipins in overweight and obese subjects

Cardiometabolic disease risk factors, including obesity, insulin resistance, high blood pressure, and dyslipidemia, are associated with elevated oxidative stress biomarkers like oxylipins. Increased adiposity by itself induces various isomers of this oxidized lipid family, while dietary polyphenols show benefits in its regulation. Previously, we showed that specific co-abundant microorganisms characterized the gut microbiota of Colombians and associated differentially with diet, lifestyle, obesity, and cardiometabolic health status, which led us to hypothesize that urinary oxylipins would reflect the intensity of oxidative metabolism linked to gut microbiota dysbiosis. Thus, we selected a convenience sample of 105 participants (age: 40.2 ± 11.9 years, 47.6% women), grouped according to microbiota, cardiometabolic health status, and body mass index (BMI); and evaluated 33 urinary oxylipins by HPLC-QqQ-MS/MS (e.g., isoprostanes, prostaglandins, and metabolites), paired with anthropometry and blood chemistry information and dietary antioxidants estimated from a 24-h food recall. In general, oxylipins did not show differences among individuals who differed in gut microbiota. While the unmetabolized oxylipin levels were not associated with BMI, the total content of oxylipin metabolites was highest in obese and cardiometabolically abnormal subjects (e.g., insulin resistant), mainly by prostaglandin-D (2,3-dinor-11β-PGF) and 15-F-IsoPs (2,3-dinor-15-F-IsoP and 2,3-dinor-15-epi-15-F-IsoP) metabolites. The total polyphenol intake in this cohort was 1070 ± 627 mg/day. After adjusting for body weight, the polyphenol intake was significantly higher in lean than overweight and showed an inverse association with dinor-oxylipin levels in principal component analysis. These results suggest that the 2,3-dinor-oxylipins could be more specific biomarkers associated with BMI than their parent oxylipins and that are sensitive to be regulated by dietary antioxidants.The authors thank the volunteers who agreed to participate in this study, the Colombian Ministry of science, technology, and innovation (Minciencias; grant number 832-2018), and Grupo Empresarial Nutresa. They also thank the Ibero-American Programme for Science, Technology and Development (CYTED) – Action 112RT0460 CORNUCOPIA networ

Desarrollo de una metodología para el análisis de residuos de plaguicidas en leches mediante cromatografía líquida acoplada a espectrometría de masas

Se desarrolló un método multirresiduo para el análisis de plaguicidas en leche mediante el empleo de cromatografía líquida acoplada a espectrometría de masas. Se estudiaron diferentes variaciones al método de extracción QuEChERS utilizando siete diferentes fases extractantes, dos sales amortiguadoras, tres concentraciones de ácido fórmico en la fase extractante y cuatro tiempos de ultrasonido. De los 58 plaguicidas analizados solo tiociclam y tiodicarb presentaron porcentajes de recuperación inferiores al 70%. Los mejores porcentajes de recuperación y menores coeficientes de variación se obtuvieron empleando el buffer de citrato y acetonitrilo con ácido fórmico al 0,5% como extractante. Por otro lado, no se observaron diferencias estadísticas (P > 0,05) a los tiempos de ultrasonido evaluados. Finalmente, se encontró que el método aplicado es preciso y exacto para el análisis de residuos de plaguicidas de diferentes grupos químicos como: azoles, organofosforados, bencimidazoles, carbamatos, entre otros.It was developed a multi-residue method for determining pesticides of different physicochemical characteristics presents on milk. The extraction process is based on the QuEChERS method and determination of the compounds was performed using ultra performance liquid chromatography coupled to mass spectrometry. Also, were evaluated seven different phases of extraction, the effect of different times of ultrasound and three concentrations of formic acidon the extraction process. The repeatability of the method results indicated that for most of the compounds showed coefficients of variation below 10%. Furthermore, it was found that there were no statistical differences (P> 0.05) at different times of ultrasound evaluation. Finally, it was found that the developed method is precise and accurate for the analysis of pesticide residues from different chemical groups such as azoles, organophosphorus, benzimidazoles, carbamates, among others

Multisite Phosphorylation Provides an Effective and Flexible Mechanism for Switch-Like Protein Degradation

Phosphorylation-triggered degradation is a common strategy for elimination of regulatory proteins in many important cell signaling processes. Interesting examples include cyclin-dependent kinase inhibitors such as p27 in human and Sic1 in yeast, which play crucial roles during the G1/S transition in the cell cycle. In this work, we have modeled and analyzed the dynamics of multisite-phosphorylation-triggered protein degradation systematically. Inspired by experimental observations on the Sic1 protein and a previous intriguing theoretical conjecture, we develop a model to examine in detail the degradation dynamics of a protein featuring multiple phosphorylation sites and a threshold site number for elimination in response to a kinase signal. Our model explains the role of multiple phosphorylation sites, compared to a single site, in the regulation of protein degradation. A single-site protein cannot convert a graded input of kinase increase to much sharper output, whereas multisite phosphorylation is capable of generating a highly switch-like temporal profile of the substrate protein with two characteristics: a temporal threshold and rapid decrease beyond the threshold. We introduce a measure termed temporal response coefficient to quantify the extent to which a response in the time domain is switch-like and further investigate how this property is determined by various factors including the kinase input, the total number of sites, the threshold site number for elimination, the order of phosphorylation, the kinetic parameters, and site preference. Some interesting and experimentally verifiable predictions include that the non-degradable fraction of the substrate protein exhibits a more switch-like temporal profile; a sequential system is more switch-like, while a random system has the advantage of increased robustness; all the parameters, including the total number of sites, the threshold site number for elimination and the kinetic parameters synergistically determine the exact extent to which the degradation profile is switch-like. Our results suggest design principles for protein degradation switches which might be a widespread mechanism for precise regulation of cellular processes such as cell cycle progression

Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory

The Auger Engineering Radio Array (AERA) is part of the Pierre Auger Observatory and is used to detect the radio emission of cosmic-ray air showers. These observations are compared to the data of the surface detector stations of the Observatory, which provide well-calibrated information on the cosmic-ray energies and arrival directions. The response of the radio stations in the 30 to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of the incoming electric field. For the latter, the energy deposit per area is determined from the radio pulses at each observer position and is interpolated using a two-dimensional function that takes into account signal asymmetries due to interference between the geomagnetic and charge-excess emission components. The spatial integral over the signal distribution gives a direct measurement of the energy transferred from the primary cosmic ray into radio emission in the AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air shower arriving perpendicularly to the geomagnetic field. This radiation energy -- corrected for geometrical effects -- is used as a cosmic-ray energy estimator. Performing an absolute energy calibration against the surface-detector information, we observe that this radio-energy estimator scales quadratically with the cosmic-ray energy as expected for coherent emission. We find an energy resolution of the radio reconstruction of 22% for the data set and 17% for a high-quality subset containing only events with at least five radio stations with signal.Comment: Replaced with published version. Added journal reference and DO

Measurement of the Radiation Energy in the Radio Signal of Extensive Air Showers as a Universal Estimator of Cosmic-Ray Energy

We measure the energy emitted by extensive air showers in the form of radio emission in the frequency range from 30 to 80 MHz. Exploiting the accurate energy scale of the Pierre Auger Observatory, we obtain a radiation energy of 15.8 \pm 0.7 (stat) \pm 6.7 (sys) MeV for cosmic rays with an energy of 1 EeV arriving perpendicularly to a geomagnetic field of 0.24 G, scaling quadratically with the cosmic-ray energy. A comparison with predictions from state-of-the-art first-principle calculations shows agreement with our measurement. The radiation energy provides direct access to the calorimetric energy in the electromagnetic cascade of extensive air showers. Comparison with our result thus allows the direct calibration of any cosmic-ray radio detector against the well-established energy scale of the Pierre Auger Observatory.Comment: Replaced with published version. Added journal reference and DOI. Supplemental material in the ancillary file

Measurement of the cosmic ray spectrum above 4×10184{\times}10^{18} eV using inclined events detected with the Pierre Auger Observatory

A measurement of the cosmic-ray spectrum for energies exceeding $4{\times}10^{18}$ eV is presented, which is based on the analysis of showers with zenith angles greater than $60^{\circ}$ detected with the Pierre Auger Observatory between 1 January 2004 and 31 December 2013. The measured spectrum confirms a flux suppression at the highest energies. Above $5.3{\times}10^{18}$ eV, the "ankle", the flux can be described by a power law $E^{-\gamma}$ with index $\gamma=2.70 \pm 0.02 \,\text{(stat)} \pm 0.1\,\text{(sys)}$ followed by a smooth suppression region. For the energy ($E_\text{s}$) at which the spectral flux has fallen to one-half of its extrapolated value in the absence of suppression, we find $E_\text{s}=(5.12\pm0.25\,\text{(stat)}^{+1.0}_{-1.2}\,\text{(sys)}){\times}10^{19}$ eV.Comment: Replaced with published version. Added journal reference and DO

Estudio cualitativo sobre decisión vocacional

El estudio cualitativo sobre decisión vocacional reúne los resultados del análisis realizado a estudiantes que participaron de la estrategia Monitores Líderes del Plan Digital Itagüí y que están cerca de finalizar los estudios de secundaria. La exploración buscó identificar los factores incidentes en la decisión sobre los planes de estudio, además de las posibles tendencias y áreas de profundización frente al tema de decisión vocacional