Particle-in-cell simulations of Alfv\'en wave parametric decay in a low-beta plasma

We study the parametric decay instability of parallel propagating Alfv\'en wave in a low-beta plasma using one-dimensional fully kinetic simulations. We focus for the first time on the conversion of the energy stored in the initial Alfv\'en wave into particle internal energy, and on its partition between particle species. We show that compressible fluctuations generated by the decay of the pump wave into a secondary ion-acoustic mode and a reflected Alfv\'en wave contribute to the gain of internal energy via two distinct mechanisms. First, the ion-acoustic mode leads nonlinearly to proton trapping and proton phase space mixing, in agreement with previous work based on hybrid simulations. Second, during the nonlinear stage, a compressible front of the fast type develops at the steepened edge of the backward Alfv\'en wave leading to a field-aligned proton beam propagating backwards at the Alfv\'en speed. We find that parametric decay heats preferentially protons, which gain about 50% of the pump wave energy in the form of internal energy. However, we find that electrons are also energized and that they contribute to the total energy balance by gaining 10% of the pump wave energy. By investigating energy partition and particle heating during parametric decay, our results contribute to determine the role of compressible and kinetic effects in wave-driven models of the solar wind

Diez para Dios. El diezmo y su arrendamiento en el Valle de Toluca, 1650 1700

Durante el periodo novohispano, el arrendamiento y la cobranza del diezmo eclesiástico estuvieron ligados íntimamente a la actividad productiva de la tierra, sobre todo a la agricultura y ganadería. El Valle de Toluca fue un bastión importante en el arrendamiento del diezmo, de acuerdo con los protocolos de la Notaría N° 1 de Toluca. En la transacción económica Iglesiaparticulares podemos encontrar hacendados de renombre y/o personas que se prestaban como fiadores para la actividad que redituó ganancias a la Iglesia católica. Para la argumentación de este artículo se consultaron fuentes primarias de archivo, siendo el principal el Archivo General de Notarías del Estado de México, en su sección histórica.Durante el periodo novohispano, el arrendamiento y la cobranza del diezmo eclesiástico estuvieron ligados íntimamente a la actividad productiva de la tierra, sobre todo a la agricultura y ganadería. El Valle de Toluca fue un bastión importante en el arrendamiento del diezmo, de acuerdo con los protocolos de la Notaría N° 1 de Toluca. En la transacción económica Iglesiaparticulares podemos encontrar hacendados de renombre y/o personas que se prestaban como fiadores para la actividad que redituó ganancias a la Iglesia católica. Para la argumentación de este artículo se consultaron fuentes primarias de archivo, siendo el principal el Archivo General de Notarías del Estado de México, en su sección histórica

Violencia de género en precedentes judiciales penales en el distrito judicial de Lima Norte, 2021

La realización de la presente investigación se ha basado en estudiar la Violencia de Género en los precedentes Judiciales Penales de la Corte Superior de Justicia de Lima Norte, teniendo como enfoque – Investigación CUALITATIVA, con un tipo de investigación básica; y, con la finalidad de recabar toda la información necesaria relacionado al tema, se ha recurrido a la entrevista con los operadores de justicia, advirtiéndose que la Violencia de Género afecta a la mujer por su condición de tal, sucesos que se vienen dando a nivel Nacional, sin discriminar los diversos niveles sociales, culturales, siendo una constante, la carencia de recursos económicos, falta de oportunidades laborales a las mujeres, el Machismo imperante en la Sociedad y sobre todo la discriminación hacia la mujer. Aunado a ello, se tiene la poca participación del Estado en dotar a los operadores de justicia encargados de sancionar a los agresores, material logístico, así como la capacitación constante en temas de violencia de género e internalizar y sensibilizar, respecto de frenar todo tipo de violencia hacia la mujer y evitar lo que actualmente se está lamentando – el Feminicidio

Characterisation and optimisation of biosorption of metals by dealginated seaweed.

The ability of dealginated seaweed, a waste material derived from the commercial processing of seaweed for alginate production, to remove cadmium, lead, nickel, copper, chromium, silver, aluminium and gold from solution was determined. Metal sorption was found to be rapid (90% removal within 5 minutes), achieving a residual concentration of 0.9 mg L[-1] after 1 h contact time from an initial solution concentration of 10 mg L[-1]. The binding of metal by dealginate was found to be pH dependent, optimal sorption occurring at around pH 6-8 for cadmium, lead, nickel, copper and chromium and pH 3-4 for aluminium and gold respectively, suggesting an ion exchange mechanism. Determination of a molar ratio in the displacement of calcium by cadmium on dealginate supported the presence of an ion-exchange relationship, since the displacement of approximately 1 mol of calcium by 1 mol of cadmium was observed.The sorption data was best fitted in the ion exchange approximation as opposed to the Langmuir model. The binding capacities were found to be 1.2, 0.5, 1.6, 0.8, 1.2, 0.4, 0.9 and 0.4 mmol g-1 for cadmium, lead, nickel, copper, chromium, silver, aluminium and gold respectively. The ion exchange constants were calculated to be 3.3 x 10[-6], 4.1 x 10[-6], 6.2 x 10[-6], 1.8 x 10[-6], 2.3 x 10[-6], 2.4 x 10[-7],8 x 10[-10] for cadmium, lead, nickel, copper, chromium, silver and aluminium. The values of the capacities and ion exchange constants showed affinity of the biosorbent to specific metals. The identification of the binding sites on the surface of dealginated seaweed was investigated by a number of techniques. Potentiometric titration revealed three distinct pKa values, the first having a similar value to carboxyl groups, the second being comparable with that of saturated thiols and amines and the third similar to sulphonate groups. Esterification of the dealginate resulted in the subsequent reduction in metal sorption, indicating that carboxyl groups are largely responsible for sorption except in the case of aluminium and gold, where 40-60% of the metal remained in solution after modification of the surface. Evidence of the FT-IR spectra confirmed the presence of carboxyl groups in untreated dealginate, while the number of carboxyl groups was markedly reduced in the esterified sample.The occurrence of other mechanisms apart from ion exchange was suggested by the FT-IR spectrum for aluminium and gold. ESEM images of the surface of dealginated seaweed showed the algae cell structure still present in large areas. X-ray maps revealed the presence of silver, aluminium and gold associated with sulphur atoms on the dealginate surface. EXAFS results showed that cadmium, lead, copper and silver were bound to the dealginate through oxygen atoms, possibly from carboxylate groups. Evidence of gold reduction from Au (III) to Au(l) and Au(O) was also confirmed by the bond distance calculated for this metal.Methods for the on-line preconcentration of cadmium, chromium, copper and lead and chemical speciation of Cr[3+] and CrO[4][2-] using a microcolumn packed with dealginated seaweed were developed. Effective column capacities were 4.0, 8.7, 9.4 and 8.5 mumol L[-1] for cadmium, chromium, copper and lead, respectively. The application of the method was extended to the determination of zinc, cobalt, mercury, scandium, strontium, vanadium, arsenic, selenium, manganese and antimony. The analytical procedures developed for metal preconcentration and chromium speciation were validated by analyses of two Lake Ontario reference materials, TMDA 51.2 and TMDA 54.2 and a synthetic seawater sample. The findings of this study demonstrated that the sorption of metal by dealginate is mainly due to an ion-exchange mechanism. The binding capacities of the biosorbent for the elements studied were adequate for trace analysis and the use of dealginate was shown to be a cheaper alternative to synthetic resins

Enfoque actuarial del impacto económico en México de la prueba “Evaluación Nacional del Logro Académico en Centros Escolares (ENLACE)” para el periodo 2006-2013.

El presente documento desarrolla un tema que actualmente ha causado gran cantidad de opiniones críticas, la Evaluación Nacional del Logro en los Centros Escolares (ENLACE), una evaluación educativa considerada como referente del nivel de desempeño de la población estudiantil en educación básica y media superior, la cual permitía a los padres de familia o tutores detectar las áreas de oportunidad y mejora en el aprovechamiento escolar de sus hijos, así como las asignaturas que requieren mayor atención; el problema es que para el presente año la aplicación de la prueba fue suspendida temporalmente para su revisión y fortalecimiento generando todo tipo de comentarios hacia las autoridades por parte de la opinión pública, los cuales exigían que se aplicara porque les proporcionaba alto contenido informativo que permitía a las autoridades la toma de decisiones de mejora en materia educativa

A discordance analysis in manual labelling of urban mobile laser scanning data used for deep learning based semantic segmentation

Labelled point clouds are crucial to train supervised Deep Learning (DL) methods used for semantic segmentation. The objective of this research is to quantify discordances between the labels made by different people in order to assess whether such discordances can influence the success rates of a DL based semantic segmentation algorithm. An urban point cloud of 30 m road length in Santiago de Compostela (Spain) was labelled two times by ten persons. Discordances and its significance in manual labelling between individuals and rounds were calculated. In addition, a ratio test to signify discordance and concordance was proposed. Results show that most of the points were labelled accordingly with the same class by all the people. However, there were many points that were labelled with two or more classes. Class curb presented 5.9% of discordant points and 3.2 discordances for each point with concordance by all people. In addition, the percentage of significative labelling differences of the class curb was 86.7% comparing all the people in the same round and 100% comparing rounds of each person. Analysing the semantic segmentation results with a DL based algorithm, PointNet++, the percentage of concordance points are related with F-score value in R2 = 0.765, posing that manual labelling has significant impact on results of DL-based semantic segmentation methods.Xunta de Galicia | Ref. ED481B-2019-061Ministerio de Ciencia e Innovación | Ref. PID2019-105221RB-C43Ministère de l’Economie of the G. D. of Luxembourg | Ref. SOLSTICE 2019-05-030-24Universidade de Vigo/CISU

Editorial: Human rights and inequity in health access of Central American Migrants

Frontiers in Public Health is very pleased to publish this journal issue focusing on the health access of immigrants. Contributions to this journal issue include five articles that rely on different methodologies while focusing on diverse geographic world regions and target populations. This editorial summarizes these features while also highlighting the unique contributions of each article

Molecular Analysis of Activation-Induced Cytidine Deaminase Gene in Immunoglobulin-E Deficient Patients

Understanding how class switch recombination (CSR) is regulated to produce immunoglobulin E (IgE) has become fundamental because of the dramatic increase in the prevalence of IgE-mediated hypersensitivity reactions. CSR requires the induction of the enzyme AICDA in B cells. Mutations in AICDA have been linked to Hyper-IgM syndrome (HIGM2), which shows absence of switching to IgE as well as to IgG and IgA. Although isolated IgE deficiency is a rare entity, here we show some individuals with normal serum IgM, IgG, and IgA levels that had undetectable total serum IgE levels. We have analyzed the AICDA gene in these individuals to determine if there are mutations in AICDA that could lead to selective IgE deficiency. Conformational sensitive gel electrophoresis (CSGE) and sequencing analysis of AICDA coding sequences demonstrated sequence heterogeneity due to 5923A/G and 7888C/T polymorphisms, but did not reveal any novel mutation that might explain the selective IgE deficit

Realistic correction of sky-coloured points in Mobile Laser Scanning point clouds

The enrichment of the point clouds with colour images improves the visualisation of the data as well as the segmentation and recognition processes. Coloured point clouds are becoming increasingly common, however, the colour they display is not always as expected. Errors in the colouring of point clouds acquired with Mobile Laser Scanning are due to perspective in the camera image, different resolution or poor calibration between the LiDAR sensor and the image sensor. The consequences of these errors are noticeable in elements captured in images, but not in point clouds, such as the sky. This paper focuses on the correction of the sky-coloured points, without resorting to the images that were initially used to colour the whole point cloud. The proposed method consists of three stages. First the region of interest where the erroneously coloured points are accumulated, is selected. Second, the sky-coloured points are detected by calculating the colour distance in the Lab colour space to a sample of the sky-colour. And third, the colour of the sky-coloured detected points is restored from the colour of the nearby points. The method is tested in ten real case studies with their corresponding point clouds from urban and rural areas. In two case studies, sky-coloured points were assigned manually and the remaining eight case studies, the sky-coloured points are derived from the acquisition errors. The algorithm for sky-coloured points detection obtained an average F1-score of 94.7%. The results show a correct reassignment of colour, texture, and patterns, while improving the point cloud visualisation.Financiado para publicación en acceso aberto: Universidade de Vigo/CISUGXunta de Galicia | Ref. ED481B-2019-061Xunta de Galicia | Ref. ED431C 2020/01Agencia Estatal de Investigación | Ref. PID2019-105221RB-C43Agencia Estatal de Investigación | Ref. PID2019-108816RB-I0