Review of Play and Preisach Models for Hysteresis in Magnetic Materials.

This paper studies the properties of the Preisach model and the play model, and compare their similarities. Both are history-dependent hysteresis models that are used to model magnetic hysteresis. They are described as discrete sums of simple hysteresis operators but can easily be reformulated as integral equations of continuous distribution functions using either a Preisach weight distribution function or a play distribution function. The models are mostly seen as phenomenological or mathematical tools but can also be related to friction-like pinning of domain-wall motions, where Rayleigh's law of magnetic hysteresis can be seen as the simplest case on either the play model or the Preisach model. They are poor at modeling other domain behavior, such as nucleation-driven hysteresis. Yet another hysteresis model is the stop model, which can be seen as the inverted version of the play model. This type of model has advantages for expressions linked to energy and can be related to Steinmetz equation of hysteresis losses. The models share several mathematical properties, such as the congruency property and wiping-out property, and both models have a history of dependence that can be described by the series of past reversal points. More generally, it is shown that the many models can be expressed as Preisach models, showing that they can be treated as subcategories of the Preisach type models. These include the play model, the stop model and also the alternative KP-hysteron model.

Impact of Early Relational Trauma on Psychic Processes: Implications for Treatment of vulnerable Children and Families / Impacto do Trauma Relacional Precoce nos Processos Psíquicos em Famílias Vulneráveis: Implicações para o Tratamento de Crianças e Famílias

ABSTRACT Numerous works and clinical research conducted in various institutions have cast fresh light on the notion of trauma and have contributed to the emergence of the concept of early relational trauma. Early relational trauma is a form of trauma rendered complex by the multiplicity of its sources and its modes of expression. Its main features are often attachment and acting-out disturbances. In families where such trauma occurs, links could sometimes be perverted and form a narcissistic configuration. This mode of functioning, organized around negativity, impacts the plurality of psychic processes and interferes with the treatment approaches of multidisciplinary teams. In order to promote a multifocal approach to care tailored to differences in situations, educational and socio-judicial practitioners.

RESUMO Inúmeros trabalhos e pesquisas clínicas realizados em diversas instituições trouxeram à luz a noção de trauma e contribuíram para o surgimento do conceito de trauma relacional precoce. O trauma relacional precoce é uma forma de trauma complexo pela multiplicidade de suas fontes e seus modos de expressão. Suas principais características são frequentemente distúrbios de apego e atuação. Nas famílias onde ocorre tal trauma que às vezes pode ser pervertido em configurações narcísicas, esse modo de funcionamento organizado em torno da negatividade impacta a pluralidade do psíquico e interfere nas abordagens de tratamento das equipes multidisciplinares. Para promover uma abordagem multifocal de cuidados adaptados às diferenças de situações, profissionais de educação e sócio judiciais.

Modeling Marek's disease virus transmission: A framework for evaluating the impact of farming practices and evolution.

Marek's disease virus (MDV) is a pathogen of chickens whose control has twice been undermined by pathogen evolution. Disease ecology is believed to be the main driver of this evolution, yet mathematical models of MDV disease ecology have never been confronted with data to test their reliability. Here, we develop a suite of MDV models that differ in the ecological mechanisms they include. We fit these models with maximum likelihood using iterated filtering in 'pomp' to data on MDV concentration in dust collected from two commercial broiler farms. We find that virus dynamics are influenced by between-flock variation in host susceptibility to virus, shedding rate from infectious birds, and cleanout efficiency. We also find evidence that virus is reintroduced to farms approximately once per month, but we do not find evidence that virus sanitization rates vary between flocks. Of the models that survive model selection, we find agreement between parameter estimates and previous experimental data, as well as agreement between field data and the predictions of these models. Using the set of surviving models, we explore how changes to farming practices are predicted to influence MDV-associated condemnation risk (production losses at slaughter). By quantitatively capturing the mechanisms of disease ecology, we have laid the groundwork to explore the future trajectory of virus evolution.