Anisotropy of third-order structure functions in MHD turbulence

The measure of the third-order structure function, Y, is employed in the solar wind to compute the cascade rate of turbulence. In the absence of a mean field B0=0, Y is expected to be isotropic (radial) and independent of the direction of increments, so its measure yields directly the cascade rate. For turbulence with mean field, as in the solar wind, Y is expected to become more two dimensional (2D), that is, to have larger perpendicular components, loosing the above simple symmetry. To get the cascade rate one should compute the flux of Y, which is not feasible with single-spacecraft data, thus measurements rely upon assumptions about the unknown symmetry. We use direct numerical simulations (DNS) of magneto-hydrodynamic (MHD) turbulence to characterize the anisotropy of Y. We find that for strong guide field B0=5 the degree of two-dimensionalization depends on the relative importance of shear and pseudo polarizations (the two components of an Alfv\'en mode in incompressible MHD). The anisotropy also shows up in the inertial range. The more Y is 2D, the more the inertial range extent differs along parallel and perpendicular directions. We finally test the two methods employed in observations and find that the so-obtained cascade rate may depend on the angle between B0 and the direction of increments. Both methods yield a vanishing cascade rate along the parallel direction, contrary to observations, suggesting a weaker anisotropy of solar wind turbulence compared to our DNS. This could be due to a weaker mean field and/or to solar wind expansion.Comment: Some text editing and typos corrected, 13 pages, 6 figures, to be published in Ap

Fuzzy Line Bundles, the Chern Character and Topological Charges over the Fuzzy Sphere

Using the theory of quantized equivariant vector bundles over compact coadjoint orbits we determine the Chern characters of all noncommutative line bundles over the fuzzy sphere with regard to its derivation based differential calculus. The associated Chern numbers (topological charges) arise to be non-integer, in the commutative limit the well known integer Chern numbers of the complex line bundles over the 2-sphere are recovered.Comment: Latex2e, 13 pages, 1 figure. This paper continues and supersedes math-ph/0103003. v2: Typos correcte

Line intensity enhancements in stellar coronal X-ray spectra due to opacity effects

Context. The I(15.01 A)/I(16.78 A) emission line intensity ratio in Fe XVII has been reported to deviate from its theoretical value in solar and stellar X-ray spectra. This is attributed to opacity in the 15.01 A line, leading to a reduction in its intensity, and was interpreted in terms of a geometry in which the emitters and absorbers are spatially distinct. Aims. We study the I(15.01 A)/I(16.78 A) intensity ratio for the active cool dwarf EV Lac, in both flare and quiescent spectra. Methods. The observations were obtained with the Reflection Grating Spectrometer on the XMM-Newton satellite. The emission measure distribution versus temperature reconstruction technique is used for our analysis. Results. We find that the 15.01 A line exhibits a significant enhancement in intensity over the optically thin value. To our knowledge, this is the first time that such an enhancement has been detected on such a sound statistical basis. We interpret this enhancement in terms of a geometry in which the emitters and absorbers are not spatially distinct, and where the geometry is such that resonant pumping of the upper level has a greater effect on the observed line intensity than resonant absorption in the line-of-sight.Comment: accepted for publication in A&

Potential Use of Papaya Flower Extract (Carica papaya Linn) for Aedes Aegypti Larvicide

Introduction: Temefos as a larvicide to prevent dengue hemorrhagic fever is known to be resistant to Aedes aegypti larvae in several regions in Indonesia. Therefore, alternative larvicides are needed. Papaya plants are one of the alternative solutions as papaya flowers contain secondary metabolite compounds that can kill Aedes aegypti larvae. This study aimed to determine the potential of papaya flower extract to be an Aedes aegypti larvicide.Methods : This study was a true experimental study with a posttest-only control group design, with 6 treatment groups namely 1%, 5%, 10%, 15%, and 20% extract concentrations (Experimental Group) and distilled water (Control Group). The experiment was repeated 4 times with a testing time of 24 hours. A total 600 Aedes aegypti instar larvae III/IV were used. Larvae toxicity was analyzed using Probit Analysis to determine the value of Lethal Concentration (LC) and Lethal Time (LT) and the Kruskall-Wallis test to determine the differences of larval deaths in each experimental group. Results: Results showed that the highest and the lowest average larval mortality was at 20% concentration (25 larvae) and 1% concentration (14.75 larvae), respectively.  and values were 4.84% and 10.39%, while values of five concentrations were 115.74, 24.24, 23.41, 25.24, and 16.55 hours and values of five concentrations were 241.95, 29.42, 26.20, 32.24, and 24.48 hours. There was a difference in the number of larval deaths after 24 hours of treatment in the experimental group (p-value = 0.011).Conclusion: Papaya flower extract has the potential to be an Aedes aegypti larvicide with 20% concentration as the optimum dose. However, phytochemical screening needs to be done to determine the dominant papaya flower compounds act as Aedes aegypti larvicides.

Polynomial identities and noncommutative versal torsors

To any cleft Hopf Galois object, i.e., any algebra H[t] obtained from a Hopf algebra H by twisting its multiplication with a two-cocycle t, we attach two "universal algebras" A(H,t) and U(H,t). The algebra A(H,t) is obtained by twisting the multiplication of H with the most general two-cocycle u formally cohomologous to t. The cocycle u takes values in the field of rational functions on H. By construction, A(H,t) is a cleft H-Galois extension of a "big" commutative algebra B(H,t). Any "form" of H[t] can be obtained from A(H,t) by a specialization of B(H,t) and vice versa. If the algebra H[t] is simple, then A(H,t) is an Azumaya algebra with center B(H,t). The algebra U(H,t) is constructed using a general theory of polynomial identities that we set up for arbitrary comodule algebras; it is the universal comodule algebra in which all comodule algebra identities of H[t] are satisfied. We construct an embedding of U(H,t) into A(H,t); this embedding maps the center Z(H,t) of U(H,t) into B(H,t) when the algebra H[t] is simple. In this case, under an additional assumption, A(H,t) is isomorphic to B(H,t) \otimes_{Z(H,t)} U(H,t), thus turning A(H,t) into a central localization of U(H,t). We work out these constructions in full detail for the four-dimensional Sweedler algebra.Comment: 39 page

Improving Harmonic Measurements with Instrument Transformers: a Comparison Among Two Techniques

The measurement of harmonics is essential in modern power systems in order to perform distortion level assessment, disturbances source detection and mitigation, etc. In this context, the role of Instrument Transformers (ITs) is crucial, as they are key elements in every power systems measuring instrument. However, inductive ITs, which are still the most widely used, suffer from both a filtering behavior due to their dynamics and from nonlinear effects due to their iron core. The target of this paper is to deeply analyze the performance of two digital signal processing techniques, recently proposed in literature, aimed at mitigating their nonlinear behavior: they are SINDICOMP and the compensation of harmonic distortion through polynomial modeling in the frequency domain. Their performance in improving the measurement of voltage harmonics are analyzed through numerical simulations, by adopting waveforms that can be typically encountered in power systems during normal operating conditions

Genetic characterization of South Spain Boar

The wild boar, a cinegetic species of Iberian Peninsula, has numerous sub-populations of Sus scrofa mediterraneus. Doñana National Park is the most important biological reserves in Spain and the largest protected area with great ecological diversity, distributed on three basic types of ecosystems: sand dunes, beaches and marshes. Here live together a variety of species: mammals, birds, reptiles, fishes... and, among them, the wild boar. In order to determine the genetic diversity, also in comparison with other Spanish populations, we studied 25 microsatellite pigs markers and found genetic variation within and among populations by analysis of heterozygosity (0.53), number of alleles (5.60), deviation by HW equili-brium and Fis index (0.02).El jabalí de interés cinegético en la península Ibérica, cuenta con numerosas sub-poblaciones de Sus scrofa mediterraneus. El Parque Nacional Doñana es la reserva biológica más importante de España y la mayor superficie protegida con gran diversidad ecológica distribuida en tres tipos básicos de ecosistemas: dunas, playas y marismas en los que cohabita gran variedad de mamíferos, aves, reptiles, peces.... entre los que se cuentan poblaciones de jabalí. Para conocer su diversidad genética, en comparación con otras poblaciones españolas, se han estudiado 25 marcadores microsatélites porcinos y se ha determinado la variación genética dentro y entre poblaciones mediante el análisis de la heterocigosis (0,53), número de alelos (5,60), desviación del equilibrio de HW y Fis (0,02)

Prototipo de un dispositivo para la medición automática de señales fisiológicas para asistir al diagnóstico y seguimiento de pacientes con COVID-19

This article describes the design, construction and preliminary results of a device to automate the measurement of physiological signals to assist in the diagnosis and monitoring of COVID-19. The device uses a system to controlling linear actuators to turn on/off certified biomedical instruments, in addition to algorithms for image recognition of displays with measurements of temperature, oxygen saturation, pressure and heart rate. The system also includes a mobile application, which receives data in real time and creates a database for medical evaluation. Results obtained with the device have demonstrated to provide a high percentage of efficiency in the data acquisition. After several trials with users, SUS and PSSUQ tests were applied to allow verifying the users’ feedback regarding the satisfaction and usability of the prototype, with high score, showing the good acceptance of the device from the users.En el presente artículo se describe el diseño, construcción y resultados preliminares de un dispositivo para automatizar la medición de señales fisiológicas para asistir el diagnóstico y seguimiento de la COVID-19. El dispositivo utiliza un sistema para controlar actuadores lineales para encender/apagar instrumentos biomédicos certificados, además de algoritmos para el reconocimiento de imágenes de las pantallas de los instrumentos con mediciones de temperatura, saturación de oxígeno, presión arterial y frecuencia cardiaca. El sistema incluye también una aplicación móvil que recibe los datos de las mediciones a tiempo real y crea una base de datos para realizar una evaluación médica. Los resultados obtenidos demuestran un alto porcentaje de eficiencia en la adquisición de las mediciones. Después de hacer varias pruebas con usuarios, las evaluaciones SUS y PSSUQ permitieron verificar resultados satisfactorios respecto a la satisfacción y usabilidad del prototipo, demostrando la aceptación del dispositivo

Architettura stateless con uso di Singularity per il porting degli applicativi WRF-4.1.5 e BOLAM

Viene proposta una tecnologia stateless per il porting dei prodotti della ricerca su piattaforme Infrastucture As A Service (IAAS), centrata sull'uso di container basati sulla tecnologia Singularity

Chimbo-2020

Questo technical report costituisce una guida per la creazione e manutenzione della catena modellistica CHIMBO-2020 sviluppata da ISAC a partire dal 2017. Le corse operative attualmente attive e generate quotidianamente con la attuale versione di questo sistema modellistico sono: - CHIMBO @ CNR - ISAC - CHIMBO @ ARPA Sicili