A model for structural defects in nanomagnets

A model for describing structural pointlike defects in nanoscaled ferromagnetic materials is presented. Its details are explicitly developed whenever interacting with a vortex-like state comprised in a thin nanodisk. Among others, our model yields results for the vortex equilibrium position under the influence of several defects along with an external magnetic field in good qualitative agreement with experiments. We also discuss how such defects may affect the vortex motion, like its gyrotropic oscillation and dynamical polarization reversal.Comment: 8 pages, resubmitted to Journal of Applied Physic

Study of the quality of fruits of the Hylocereusundatus (Haw) Britton Rose and Hylocereusmegalanthus(K. Schum ex Vaupel) Ralf Baue (Red and Yellow Pitahaya) during the maturationperiod

In this work, the organoleptic and sensorial characteristics were determined, as well as the maturation pattern of the yellow and red pitahaya fruits grown in Ecuador. Several fruit quality indexes were evaluated for 15 days from the moment of harvest, such as: weight loss, dry matter, total soluble solids, titratable acidity, exocarp coloration and maturity relationship and related damages by attack of biotic agents. The results indicated that in storage conditions with a temperature of 25 ± 1 ° C, the red pitahaya presents a gradual loss of fruit quality up to nine days; after this period serious fungal damage to the fruit that affects its commercial quality begins. The yellow pitahaya has a time of storage that can reach up to 15 days, although the fruit looks externally dehydrated and aged; however internally the fruit maintains its quality for consumption. It presents organosensitive standards of quality and resistance to microbiological agents superior to those of the red pitahaya. Due to the behavior of the fruit in the various variables evaluated in this study, strong evidences are presented that suggest to consider it as a species of non-climacteric respiration

Alterações na composição química do milho devido ao carunchamento.

Milho BR-201 foi submetido a infestacao artificial por caruncho (Sitophilus zeamais) obtendo-se quatro lotes com diferentes niveis de carunchamento (1,79; 10,27; 17,49 e 38,15%). Em cada amostras foram retiradas e submetidas a analise proximal. Determinou-se nas amostras o teor de aminoacidos, energia bruta, densidade, micotoxinas e a presenca de insetos ou suas partes. Foi observado um aumento linear na materia seca, fibra bruta e cinzas e variacao quadratica na proteina bruta, extrato etereo, energia bruta, extrato nao nitrogenado e densidade dos graos. Nao se detectou a presenca de micotoxinas e insetos ou suas partes. Alteracoes na composicao aminoacidica foi observada

Valores de energia digestível, metabolizável e do coeficiente de digestibilidade dos nutrientes do milho em diferentes níveis de carunchamento.

Milho BR-201 foi submetido a infestacao artificial por caruncho (Sitophilus zeamais) obtendo-se quatro lotes em diferentes niveis de carunchamento (1,79%, 10,27%; 17,49% e 38,15%). Quinze suinos machos castrados foram distribuidos em um delineamento inteiramente casualizado em tres repeticoes por tratamento. As racoes experimentais foram compostas por uma racao referencia e quatro racoes compostas de 75% da racao referencia e 25% do milho a ser estudado. A elevacao do nivel de carunchamento do milho reduziu o nivel de energia digestivel e o coeficiente de digestibilidade do extrato etereo do milho, mas nao alterou o coeficiente de digestibilidade da proteina bruta, da fibra bruta e da energia metabolizavel

Multimessenger Characterization of Markarian 501 during Historically Low X-Ray and γ-Ray Activity

We study the broadband emission of Mrk 501 using multiwavelength observations from 2017 to 2020 performed with a multitude of instruments, involving, among others, MAGIC, Fermi's Large Area Telescope (LAT), NuSTAR, Swift, GASP-WEBT, and the Owens Valley Radio Observatory. Mrk 501 showed an extremely low broadband activity, which may help to unravel its baseline emission. Nonetheless, significant flux variations are detected at all wave bands, with the highest occurring at X-rays and very-high-energy (VHE) 3-rays. A significant correlation (>3σ) between X-rays and VHE 3-rays is measured, supporting leptonic scenarios to explain the variable parts of the emission, also during low activity. This is further supported when we extend our data from 2008 to 2020, and identify, for the first time, significant correlations between the Swift X-Ray Telescope and Fermi-LAT. We additionally find correlations between high-energy 3-rays and radio, with the radio lagging by more than 100 days, placing the 3-ray emission zone upstream of the radio-bright regions in the jet. Furthermore, Mrk 501 showed a historically low activity in X-rays and VHE 3-rays from mid-2017 to mid-2019 with a stable VHE flux (>0.2 TeV) of 5% the emission of the Crab Nebula. The broadband spectral energy distribution (SED) of this 2 yr long low state, the potential baseline emission of Mrk 501, can be characterized with one-zone leptonic models, and with (lepto)-hadronic models fulfilling neutrino flux constraints from IceCube. We explore the time evolution of the SED toward the low state, revealing that the stable baseline emission may be ascribed to a standing shock, and the variable emission to an additional expanding or traveling shock. © 2023. The Author(s). Published by the American Astronomical Society

Multi-messenger characterization of Mrk 501 during historically low X-ray and γ\gamma-ray activity

We study the broadband emission of Mrk 501 using multi-wavelength observations from 2017 to 2020 performed with a multitude of instruments, involving, among others, MAGIC, Fermi-LAT, NuSTAR, Swift, GASP-WEBT, and OVRO. Mrk 501 showed an extremely low broadband activity, which may help to unravel its baseline emission. Nonetheless, significant flux variations are detected at all wavebands, with the highest occurring at X-rays and very-high-energy (VHE) $\gamma$-rays. A significant correlation ($>$3$\sigma$) between X-rays and VHE $\gamma$-rays is measured, supporting leptonic scenarios to explain the variable parts of the emission, also during low activity. This is further supported when we extend our data from 2008 to 2020, and identify, for the first time, significant correlations between Swift-XRT and Fermi-LAT. We additionally find correlations between high-energy $\gamma$-rays and radio, with the radio lagging by more than 100 days, placing the $\gamma$-ray emission zone upstream of the radio-bright regions in the jet. Furthermore, Mrk 501 showed a historically low activity in X-rays and VHE $\gamma$-rays from mid-2017 to mid-2019 with a stable VHE flux ($>$0.2 TeV) of 5% the emission of the Crab Nebula. The broadband spectral energy distribution (SED) of this 2-year-long low-state, the potential baseline emission of Mrk 501, can be characterized with one-zone leptonic models, and with (lepto)-hadronic models fulfilling neutrino flux constraints from IceCube. We explore the time evolution of the SED towards the low-state, revealing that the stable baseline emission may be ascribed to a standing shock, and the variable emission to an additional expanding or traveling shock.Comment: 56 pages, 30 figures, 14 tables, submitted. Corresponding authors are L. Heckmann, D. Paneque, S. Gasparyan, M. Cerruti, and N. Sahakya

Extrusión de almidones de fuentes no convencionales para la producción de almidón resistente

Se aislaron almidones de frutos verdes de plátano (Musa paradisiaca L.) y mango (Manguifera indica L.), sometidos a un proceso de extrusión en un equipo de un sólo tornillo, para obtener un producto con alto contenido de almidón resistente (AR), el cual es un ingrediente nutraceútico utilizado en la industria de alimentos. Se usó un diseño experimental central compuesto, con tres variables independientes (temperatura, contenido de humedad y velocidad del tornillo), para conocer su efecto sobre el contenido de AR. Los almidones nativos de plátano y mango tuvieron una pureza mayor de 90%, con 37% de amilosa en el almidón de plátano y 27.5% en el almidón de mango. Ello no influyó la formación de AR, que fue 5.7% para el almidón de plátano (con más amilosa) y para el almidón de mango fue 9.7%. La formación de AR dentro del extrusor para el almidón de plátano fue afectada positivamente por la temperatura, e inversamente por la humedad. Para el almidón de mango la humedad no presentó un efecto significativo sobre la formación de AR. La validación con los modelos matemáticos mostró una alta predicción de la formación de AR en el extrusor (más de 90%). La extrusión puede ser un proceso para producir un producto con mayor contenido de AR que su almidón nativo