Critical state theory for nonparallel flux line lattices in type-II superconductors

Coarse-grained flux density profiles in type-II superconductors with non-parallel vortex configurations are obtained by a proposed phenomenological least action principle. We introduce a functional $C[H(x)]$, which is minimized under a constraint of the kind $J$ belongs to $Delta$ for the current density vector, where $Delta$ is a bounded set. This generalizes the concept of critical current density introduced by C. P. Bean for parallel vortex configurations. In particular, we choose the isotropic case ($Delta$ is a circle), for which the field penetration profiles $H(x,t)$ are derived when a changing external excitation is applied. Faraday's law, and the principle of minimum entropy production rate for stationary thermodynamic processes dictate the evolution of the system. Calculations based on the model can reproduce the physical phenomena of flux transport and consumption, and the striking effect of magnetization collapse in crossed field measurements.Comment: The compiled TeX document length is 10 pages. Two figures (one page each) are also included The paper is accepted for publication in Phys. Rev. Let

Influencia del tiempo de uso de las tecnologías de información y comunicación y subprogramas sobre las habilidades informacionales en estudiantes de la Universidad del Zulia

The purpose of this research was to determine the influence of the time of use of technologies of information and communication and related subprograms in the informational skills of students at the University of the Zulia. The research was developed under a descriptive, field based methodology, with a non-experimental design of the trans-sectional type. The population was made up of 95 students in the economic and social sciences program at the LUZ COL. Nucleus. The sample was obtained by means of the Shiffer formula and made up of a group of 52 students in the subprogram of accounting, 15 students of economy, and 18 students of administration. A random sampling stratified by subprograms was used. For the compilation of information 3 instruments were designed, the first one with 8 simple questions, the second one with 29 questions and a Lickert’s scale with four alternatives, and the third one was an observation sheet. The validation of the instrument was made by three experts in the area and there was no the need to realize a reliability test of the instrument provided that they were questionnaires. The analysis of the information was realized by the statistical program SPSS Version 10, in which tests were realized for the calculations of arithmetic averages and standard deviation, as well as analysis of variance, studies of homogeneity and Tukey comparison tests in order to determine the value of the variables in the study. The results obtained showed an influence of the time of use of TIC across the dimension of frequency of hours per week,and informational skills, specifically in the aspects of access and communication of information, and also they revealed that the subprograms do not influence these skills, where students in the program possess high use of these informational skills.El propósito de esta investigación fue determinar la influencia del tiempo de uso de las tecnologías de información y comunicación y subprogramas sobre las habilidades informacionales en estudiantes de la Universidad del Zulia. La investigación fue desarrollada bajo la metodología descriptiva, de campo, con un diseño no experimental del tipo transeccional descriptivo. La población estuvo conformada por 95 estudiantes del programa de ciencias económicas y sociales del núcleo COL de LUZ. La muestra se obtuvo mediante la fórmula de Shiffer constituyéndose por una muestra de 52 estudiantes del subprograma de contaduría, 15 de economía y 18 de administración. Se utilizó un muestreo aleatorio estratificado por subprogramas. Para la recolección de datos se diseñarón 3 instrumentos, dos cuestionarios y una hoja de observación con su respectiva validación a cargo de tres expertos. El análisis de los datos se realizó a través del programa estadístico SPSS Versión 10, en el cual se realizaron pruebas para los cálculos de media aritmética y desviación estándar, además del análisis de la varianza, estudios de Homogeneidad y pruebas de comparación de Tukey y robustas, con el fin de determinar el valor de las variables en el estudio. Los resultados obtenidos mostraron una influencia del tiempo en el uso de las TIC a través de su dimensión frecuencia de horas a la semana sobre las habilidades informacionales, específicamente en los aspectos de acceso y comunicación de la información, también revelaron que los subprogramas no influyen sobre estas destrezas, donde los estudiantes del programa poseen un uso Alto de las habilidades Informacionale

Experience of the cleft lip and palate clinic at the hospital general de México 2017-2023

Background: The care of cleft lip and palate patients at the general hospital of Mexico has nearly 70 years of experience. Methods: An observational study of a 7-year cohort of resolved cases of cleft lip and palate by the plastic and reconstructive surgery service of the general hospital of Mexico (2017-2023) was conducted. Results: The 121 patients were recorded, with 47 palatoplasties, 44 primary cheiloplasties, 24 secondary cheiloplasties, and 11 veloplasties performed. All patients are evaluated by a multidisciplinary team composed of plastic surgery, dentistry, clinical nutrition, speech therapy, audiology, genetics, and psychology to determine a comprehensive treatment plan. Conclusions: The data reported by the cohort in this work aligns with international reports. The frequency of cases decreased due to the COVID-19 pandemic, but has increased in recent years

Solo reflorestado sob irrigação por gotejamento com efluentes tratados de abatedouro de aves

[Abstract] The disposal of treated effluents on soil is the main final use of wastewater in Brazil. Although this practice can promote improvements of some soil attributes, there is a need for monitoring in order to ensure that potential environmental impacts are not harmful. Thus, the purpose of this study was to evaluate the effects of treated effluent from a poultry slaughterhouse on the chemical attributes of an Oxisols, in Matelândia-PR, Brazil under drip irrigation. The soil attributes P, K, Fe, Cu, Zn, Mn, pH in CaCl2, H + Al, Al, Ca, Mg, cation exchange capacity (CEC), and percent base saturation (V) were evaluated under four effluent application rates, 0, 100, 200 and 300 m³ ha-1 d-1 with treated effluents on three successive sampling dates. As main results it was observed that high irrigation rates increased soil phosphorus and potassium concentrations. In addition, an association between the increase of soil potential acidity and exchangeable acidity was detected, although pH did not vary significantly either between treatments or between sampling dates.[Resumo] A disposição de efluentes tratados sobre o solo pode ser considerada o principal destino final de águas residuárias no Brasil. Embora possa promover melhorias em relação a alguns atributos do solo, esta prática precisa ser monitorada para garantir que os impactos ambientais não sejam negativos. Assim, objetivou-se com este trabalho avaliar os efeitos da disposição, por gotejamento, do efluente tratado de um abatedouro de aves sobre os atributos químicos de um Latossolo, em Matelândia, PR. Os atributos do solo: P, K, Fe, Cu, Zn, Mn, pH em CaCl2, H + Al, Al, Ca, Mg, capacidade de troca catiônica (CTC), saturação por bases foram avaliados sob quatro taxas de irrigação, 0, 100, 200 e 300 m³ ha-1 d-1, com efluentes tratados em três datas sucessivas de amostragem. Como principais resultados observou-se que as altas taxas de aplicação do efluente praticadas, influenciaram no incremento das concentrações de fósforo e potássio no solo. Além disso, pôde-se observar uma relação entre o aumento da acidez potencial e acidez trocável, mesmo que o pH não tenha variado tanto nem entre os tratamentos nem entre as ocasiões de coletas de dados

GRB 221009A: A light dark matter burst or an extremely bright Inverse Compton component?

Gamma-ray bursts (GRBs) have been considered as potential very high-energy photon emitters due to the large amount of energy released as well as the strong magnetic fields involved in their jets. However, the detection of TeV photons is not expected from bursts beyond a redshift of $z\gtrsim 0.1$ due to their attenuation with the extragalactic background light (EBL). For these reasons, the recent observation of photons with energies of 18 and 251 TeV from GRB 221009A (z=0.151) last October 9th, 2022 has challenged what we know about the TeV-emission mechanisms and the extragalactic background. In order to explain the TeV observations, recent works exploring candidates of dark matter have started to appear. In this paper, we discuss the required conditions and limitations within the most plausible scenario, synchrotron-self Compton (SSC) radiation in the GRB afterglow, to interpret the one 18-TeV photon observation besides the EBL. To avoid the Klein-Nishina effect, we find an improbable value of the microphysical magnetic parameter below $10^{-6}$ for a circumburst medium value $> 1{\rm cm^{-3}}$ (expected in the collapsar scenario). Therefore, we explore possible scenarios in terms of ALPs and dark photon mechanisms to interpret this highly-energetic photon and we discuss the implications in the GRB energetics. We find that the ALPs and dark photon scenarios can explain the 18 TeV photon but not the 251 TeV photon.Comment: 15 pages, 5 figures, 4 table

Reduction of optical crosstalk in SiPMs due to coupled light guides and investigation of other properties demonstrated with the SensL MicroFJ-60035-TSV

The optical coupling of light guides to Silicon Photomultipliers (SiPMs) influences the probability for optical crosstalk. Measurements of the crosstalk probability and the relative gain of 122 SiPMs of type SensL MicroFJ-60035-TSV are presented. Semi-conductor photo sensors have replaced photo multiplier tubes in numerous applications featuring single-photon resolution, insensitivity to magnetic fields, higher robustness and enhanced photo detection efficiency at lower operation voltage and lower costs. Light guides are used to increase the comparably small photo sensitive area of SiPMs. Their optical coupling changes the surface conditions of the sensor and influences the probability for crosstalk photons to leave the sensor without inducing secondary breakdowns. This study compares properties of sensors that are optically coupled to light guides with bare sensors, operated at nominal bias voltage. It demonstrates, that the optical coupling to a light guide significantly reduces the crosstalk probability of the measured sensors

Challenges in Complex Systems Science

FuturICT foundations are social science, complex systems science, and ICT. The main concerns and challenges in the science of complex systems in the context of FuturICT are laid out in this paper with special emphasis on the Complex Systems route to Social Sciences. This include complex systems having: many heterogeneous interacting parts; multiple scales; complicated transition laws; unexpected or unpredicted emergence; sensitive dependence on initial conditions; path-dependent dynamics; networked hierarchical connectivities; interaction of autonomous agents; self-organisation; non-equilibrium dynamics; combinatorial explosion; adaptivity to changing environments; co-evolving subsystems; ill-defined boundaries; and multilevel dynamics. In this context, science is seen as the process of abstracting the dynamics of systems from data. This presents many challenges including: data gathering by large-scale experiment, participatory sensing and social computation, managing huge distributed dynamic and heterogeneous databases; moving from data to dynamical models, going beyond correlations to cause-effect relationships, understanding the relationship between simple and comprehensive models with appropriate choices of variables, ensemble modeling and data assimilation, modeling systems of systems of systems with many levels between micro and macro; and formulating new approaches to prediction, forecasting, and risk, especially in systems that can reflect on and change their behaviour in response to predictions, and systems whose apparently predictable behaviour is disrupted by apparently unpredictable rare or extreme events. These challenges are part of the FuturICT agenda

Effect of graphene oxide on bacteria and peripheral blood mononuclear cells

"Background Driven by the potential biological applications of graphene, many groups have studied the response of cells exposed to graphene oxide (GO). In particular, investigations of bacteria indicate that there are 2 crucial parameters, which so far have only been investigated separately: GO size and exposure methodology. Our study took into account both parameters. We carefully characterized the samples to catalog sizes and structural properties, and tested different exposure methodologies: exposure in saline solution and in the presence of growth media. Furthermore, we performed experiments with peripheral blood mononuclear cells exposed to our GO materials. Methods Atomic force microscopy, scanning electron microscopy, Raman spectroscopy, X-ray photoelectron spectroscopy and transmission electron microscopy were used to characterize the morphology and composition of different samples of GO: GO-H2O, GO-PBS and GO-MG. Our samples had 2D sizes of ?100 nm (GO-H2O and GO-PBS) and >2 µm (GO-MG). We tested antibacterial activity and cytotoxicity toward peripheral blood mononuclear cells of 3 different GO samples. Results A size-dependent growth inhibition of Escherichia coli (DH5 ?) in suspension was found, which proved that this effect depends strongly on the protocol followed for exposure. Hemocompatibility was confirmed by exposing peripheral blood mononuclear cells to materials for 24 hours; viability and apoptosis tests were also carried out. Conclusions Our experiments provide vital information for future applications of GO in suspension. If its antibacterial properties are to be potentiated, care should be taken to select 2D sizes in the micrometer range, and exposure should not be carried out in the presence of grow media.

Gramine derivatives targeting Ca2+ channels and Ser/Thr phosphatases: A new dual strategy for the treatment of neurodegenerative diseases

This document is the unedited author's version of a Submitted Work that was subsequently accepted for publication in Journal of Medicinal Chemistry , copyright © American Chemical Society after peer review. To access the final edited and published work, see http://pubs.acs.org/doi/abs/10.1021/acs.jmedchem.6b00478We describe the synthesis of gramine derivatives and their pharmacological evaluation as multipotent drugs for the treatment of Alzheimer’s disease. An innovative multitarget approach is presented, targeting both voltage-gated Ca2+ channels, classically studied for neurodegenerative diseases, and Ser/Thr phosphatases, which have been marginally aimed, even despite their key role in protein τ dephosphorylation. Twenty-five compounds were synthesized, and mostly their neuroprotective profile exceeded that offered by the head compound gramine. In general, these compounds reduced the entry of Ca2+ through VGCC, as measured by Fluo-4/AM and patch clamp techniques, and protected in Ca2+ overload-induced models of neurotoxicity, like glutamate or veratridine exposures. Furthermore, we hypothesize that these compounds decrease τ hyperphosphorylation based on the maintenance of the Ser/Thr phosphatase activity and their neuroprotection against the damage caused by okadaic acid. Hence, we propose this multitarget approach as a new and promising strategy for the treatment of neurodegenerative diseasesThis work was supported by the following grant: Proyectos de Investigación en Salud (PI13/00789, IS Carlos III). R.L.C is granted by Universidad Autónoma de Madri