A venting alarm system for cryogenic liquids

Alarm system for cryogenic fluid storage tank

Cognitive outcome and gamma noise power unrelated to neuregulin 1 and 3 variation in schizophrenia

Background Neuregulins are a family of signalling proteins that orchestrate a broad range of cellular responses. Four genes encoding Neuregulins 1–4 have been identified so far in vertebrates. Among them, Neuregulin 1 and Neuregulin 3 have been reported to contribute to an increased risk for developing schizophrenia. We hypothesized that three specific variants of these genes (rs6994992 and rs3924999 for Neuregulin 1 and rs10748842 for Neuregulin 3) that have been related to this illness may modify information processing capacity in the cortex, which would be reflected in electrophysiological parameters (P3b amplitude or gamma noise power) and/or cognitive performance. Methods We obtained DNA from 31 patients with schizophrenia and 23 healthy controls and analyzed NRG1 rs6994992, NRG1 rs3924999 and NRG3 rs10748842 promoter polymorphisms by allelic discrimination with real-time polymerase chain reaction (PCR). We compared cognitive outcome, P300 amplitude parameters and an electroencephalographic measure of noise power in the gamma band between the groups dichotomized according to genotype. Results Contrary to our hypothesis, we could not detect any significant influence of variation in Neuregulin 1/Neuregulin 3 polymorphisms on cognitive performance or electrophysiological parameters of patients with schizophrenia. Conclusions Despite our findings, we cannot discard that other genetic variants and, more likely, interactions between those variants and with genetic variation related to different pathways may still influence cerebral processing in schizophrenia

Late time tails of the massive vector field in a black hole background

We investigate the late-time behavior of the massive vector field in the background of the Schwarzschild and Schwarzschild-de Sitter black holes. For Schwarzschild black hole, at intermediately late times the massive vector field is represented by three functions with different decay law $\Psi_{0} \sim t^{-(\ell + 3/2)} \sin{m t}$, $\Psi_{1} \sim t^{-(\ell + 5/2)} \sin{m t}$, $\Psi_{2} \sim t^{-(\ell + 1/2)} \sin{m t}$, while at asymptotically late times the decay law $\Psi \sim t^{-5/6} \sin{(m t)}$ is universal, and does not depend on the multipole number $\ell$. Together with previous study of massive scalar and Dirac fields where the same asymptotically late-time decay law was found, it means, that the asymptotically late-time decay law $\sim t^{-5/6} \sin{(m t)}$ \emph{does not depend} also \emph{on the spin} of the field under consideration. For Schwarzschild-de Sitter black holes it is observed two different regimes in the late-time decay of perturbations: non-oscillatory exponential damping for small values of $m$ and oscillatory quasinormal mode decay for high enough $m$. Numerical and analytical results are found for these quasinormal frequencies.Comment: one author and new material are adde

Optimization of soliton ratchets in inhomogeneous sine-Gordon systems

Unidirectional motion of solitons can take place, although the applied force has zero average in time, when the spatial symmetry is broken by introducing a potential $V(x)$, which consists of periodically repeated cells with each cell containing an asymmetric array of strongly localized inhomogeneities at positions $x_{i}$. A collective coordinate approach shows that the positions, heights and widths of the inhomogeneities (in that order) are the crucial parameters so as to obtain an optimal effective potential $U_{opt}$ that yields a maximal average soliton velocity. $U_{opt}$ essentially exhibits two features: double peaks consisting of a positive and a negative peak, and long flat regions between the double peaks. Such a potential can be obtained by choosing inhomogeneities with opposite signs (e.g., microresistors and microshorts in the case of long Josephson junctions) that are positioned close to each other, while the distance between each peak pair is rather large. These results of the collective variables theory are confirmed by full simulations for the inhomogeneous sine-Gordon system

Spark Plug Simulation with the Use of Three Types of Fuels in Direct Injection Engines for the Evaluation of Polluting Factors

The present work has as main objective the use of a biofuel (Ecopaís) in a direct injection vehicle, it is an option to reduce damage to health and the environment, for this a static thermal simulation will be done in the spark plug, to compare the results of the aforementioned software using On Board tests, in a 1500 cc engine. The measurements of the emission factors of CO, HC and NOx gases will be considered in a route established in the city of Quito from 2399 to 2870 meters above sea level. The interaction of the element is carried out in the ANSYS Academic program which is 14977 nodes and 7523 elements to be studied with automatic meshing, obtaining that the Ecopaís and Ecopaís + Ferox fuels have the highest heat flow with a 5% divergence compared to the Extra fuel + Ferox. There is a significant reduction in pollutant emissions of 3% of CO with the use of Ecopaís in comparison to Extra + Ferox fuel, in the case of HC, Ecopaís and Ecopaís + Ferox fuels with 3% lower emissions compared to Extra fuel + Ferox, and in NOx, fuels that have Extra + Ferox and Ecopaís + Ferox solid additives are 3 and 3.5% lower compared to Ecopaís fuel, respectively. Keywords: biofuel, termal, on board, ferox, emission factors. Resumen El presente trabajo tiene como objetivo fundamental la utilización de un biocombustible (Ecopaís) en un vehículo de inyección directa, es una opción para disminuir daños a la salud y al medio ambiente, para ello se hará una simulación térmica estática en la bujía de encendido, para comparar los resultados del mencionado software mediante pruebas On Board, en un motor de 1500 cc. Las mediciones de los factores de emisión de gases de CO, HC y NOx, se contemplará en una ruta establecida en la ciudad de Quito de 2399 hasta 2870 m.s.n.m. La interacción del elemento se realiza en el programa ANSYS Academic que es de 14977 nodos y 7523 elementos a estudiar con el mallado automático, obteniendo que los combustibles Ecopaís y Ecopaís+Ferox tienen el mayor flujo de calor con una divergencia del 5% en comparación del combustible Extra + Ferox. Se evidencia una reducción significativa de emisiones contaminantes del 2.5% del CO con el uso del Ecopaís en comparación del combustible Extra + Ferox, en el caso de HC los combustibles Ecopaís y Ecopaís + Ferox con un 1% menor en emisiones en comparación al combustible Extra + Ferox, y en el NOx los combustibles que tienen aditivo sólido Extra+Ferox y Ecopaís+Ferox son menores en un 6 y 4% con respecto al combustible Ecopaís respectivamente. Palabras clave: biocombustible, térmica, on board, ferox, factores de emisiones

Hypocrea lixii y Trichoderma asperellum como agentes bioreguladores de Alternaria solani y Corynespora cassiicola en condiciones de laboratorio e invernadero

El cultivo de tomate (Lycopersicon esculentum Mill) en Ecuador de acuerdo a datos estadísticos del MAGAP/SIGAGRO reportan que la superficie sembrada en 2010 fue 2037 ha con producción de 43.025 Tm. Este cultivo es afectado por varios fitopatógenos de suelo y foliares que provocan pérdidas en el rendimiento, aumento en los costos de producción por efectos de control, estudios precedentes reportan que en la provincia de Manabí los productores invierten alrededor del 50% del costo de inversión en labores de combate de plagas, con promedios de 23 aplicaciones durante el ciclo de producción. Por otra parte, se ha observado que utilizan con productos extremadamente y altamente tóxicos hasta 24 horas antes de cosechar y en ciertos casos inclusive durante la misma, esto trae como consecuencia daños en la salud de personas que laboran en campo y de los consumidores, al agroecosistema; por lo que es necesario buscar alternativas amigables con la naturaleza entre ellos hongos antagonistas que reducen en forma natural el inóculo de fitopatógenos. Las enfermedades más importantes en las provincias de Guayas y Santa Elena es el tizón temprano o lancha temprana y la mancha corinespora. El tizón temprano causado por Alternaria solani es una enfermedad muy destructiva en áreas donde la humedad es alta; afecta al follaje, tallos y frutos, puede causar daños severos al cultivo en cualquier etapa del desarrollo. Los síntomas iniciales son pequeñas lesiones de color negro parduzco que aparece en hojas más viejas, el tejido que rodea la lesión toma un color amarillo; los puntos necróticos aumentan rápidamente de tamaño y cuando su diámetro es de 6 mm o más pueden distinguirse anillos concéntricos en la zona de color castaño claro. Las lesiones en el tallo de las plántulas son pequeños, oscuros y ligeramente hundidos, pero pueden aumentar de tamaño para formar lesiones circulares o alargadas con anillos concéntricos pronunciados quedando el centro de coloración más clara. La infección ocurre en la intersección al cáliz o al tallo. Tanto en estado verde o maduro; a menudo el fruto se cae y puede causar del 30-50% de frutos inmaduros

Enhanced Parallel Generation of Tree Structures for the Recognition of 3D Images

Segmentations of a digital object based on a connectivity criterion at n-xel or sub-n-xel level are useful tools in image topological analysis and recognition. Working with cell complex analogous of digital objects, an example of this kind of segmentation is that obtained from the combinatorial representation so called Homological Spanning Forest (HSF, for short) which, informally, classifies the cells of the complex as belonging to regions containing the maximal number of cells sharing the same homological (algebraic homology with coefficient in a field) information. We design here a parallel method for computing a HSF (using homology with coefficients in Z/2Z) of a 3D digital object. If this object is included in a 3D image of m1 × m2 × m3 voxels, its theoretical time complexity order is near O(log(m1 + m2 + m3)), under the assumption that a processing element is available for each voxel. A prototype implementation validating our results has been written and several synthetic, random and medical tridimensional images have been used for testing. The experiments allow us to assert that the number of iterations in which the homological information is found varies only to a small extent from the theoretical computational time.Ministerio de Economía y Competitividad MTM2016-81030-

Finitely fibered Rosenthal compacta and trees

We study some topological properties of trees with the interval topology. In particular, we characterize trees which admit a 2-fibered compactification and we present two examples of trees whose one-point compactifications are Rosenthal compact with certain renorming properties of their spaces of continuous functions.Comment: Small changes, mainly in the introduction and in final remark

First observations and magnitude measurement of Starlink's Darksat

Measure the Sloan g' magnitudes of the Starlink's STARLINK-1130 (Darksat) and 1113 LEO communication satellites and determine the effectiveness of the Darksat darkening treatment at 475.4\,nm. Two observations of the Starlink's Darksat LEO communication satellite were conducted on 2020/02/08 and 2020/03/06 using a Sloan r' and g' filter respectively. While a second satellite, STARLINK-1113 was observed on 2020/03/06 using a Sloan g' filter. The initial observation on 2020/02/08 was a test observation when Darksat was still manoeuvring to its nominal orbit and orientation. Based on the successful test observation, the first main observation was conducted on 2020/03/06 along with an observation of the second Starlink satellite. The calibration, image processing and analysis of the Darksat Sloan g' image gives an estimated Sloan g' magnitude of $7.46\pm0.04$ at a range of 976.50\,km. For STARLINK-1113 an estimated Sloan g' magnitude of $6.59\pm0.05$ at a range of 941.62\,km was found. When scaled to a range of 550\,km and corrected for the solar and observer phase angles, a reduction by a factor of two is seen in the reflected solar flux between Darksat and STARLINK-1113. The data and results presented in this work, show that the special darkening coating used by Starlink for Darksat has darkened the Sloan g' magnitude by $0.77\pm0.05$\,mag, when the range is equal to a nominal orbital height (550\,km). This result will serve members of the astronomical community modelling the satellite mega-constellations, to ascertain their true impact on both the amateur and professional astronomical communities. Concurrent and further observations are planned to cover the full optical and NIR spectrum, from an ensemble of instruments, telescopes and observatories.Comment: Accepted for publication in A&A Letters. 5 pages, 2 figures and 4 table