Multimodal Differential Emission Measure in the Solar Corona

The Atmospheric Imaging Assembly (AIA) telescope on board the Solar Dynamics Observatory (SDO) provides coronal EUV imaging over a broader temperature sensitivity range than the previous generations of instruments (EUVI, EIT, and TRACE). Differential emission measure tomography (DEMT) of the solar corona based on AIA data is presented here for the first time. The main product of DEMT is the three-dimensional (3D) distribution of the local differential emission measure (LDEM). While in previous studies, based on EIT or EUVI data, there were 3 available EUV bands, with a sensitivity range $\sim 0.60 - 2.70$ MK, the present study is based on the 4 cooler AIA bands (aimed at studying the quiet sun), sensitive to the range $\sim 0.55 - 3.75$ MK. The AIA filters allow exploration of new parametric LDEM models. Since DEMT is better suited for lower activity periods, we use data from Carrington Rotation 2099, when the Sun was in its most quiescent state during the AIA mission. Also, we validate the parametric LDEM inversion technique by applying it to standard bi-dimensional (2D) differential emission measure (DEM) analysis on sets of simultaneous AIA images, and comparing the results with DEM curves obtained using other methods. Our study reveals a ubiquitous bimodal LDEM distribution in the quiet diffuse corona, which is stronger for denser regions. We argue that the nanoflare heating scenario is less likely to explain these results, and that alternative mechanisms, such as wave dissipation appear better supported by our results.Comment: 52 pages, 18 figure

Parameters identification of HIV dynamic models for HAART treated patients: A comparative study

We present a comparative study of parameters identification of HIV dynamic models for naive patients that are treated with two different HAART (Highly Active Anti-Retroviral Therapy) protocols during a period of 48 weeks. Three HIV models of increasing complexity (in terms of number of state variables and parameters) have been chosen, and for each one the model parameters are computed by solving a nonlinear optimization problem via sequential quadratic programming (SQP). Model parameters are divided into “group dependent”, common to all patients treated with same HAART protocol, and “patient dependent”, specific for each patient, and are estimated in a way that an overall cost function comprising the fitting error of CD4+ concentration and viral load measurements. A preliminary parameter space grid search algorithm is performed in order to find a suitable initial guess for the SQP algorithm. Numerical results indicate that all considered models can give a good matching despite the scarcity of available measurements for each patient, and in this limited situation the minimal model appears to be (slightly) more effective than the other models

Physiological Cybernetics: An Old-Novel Approach for Students in Biomedical Systems

Wiener in a seminal book (Wiener, 1948) associated the ancient Greek word ‘κυβερνητικος’ to the control of physiological systems. “Thus, as far back as four years ago, the group of scientists about Dr. Rosenblueth and myself had already become aware of the essential unity of the set of problems centering about communication, control and statistical mechanics, whether in the machine or in the living tissue. [...] We have decided to call the entire field [...] by the name Cybernetics, which we form from the Greek κυβερνητης or steersman. In choosing this term, we wish to recognize that the first significant paper on feed-back mechanisms is an article on governors, which was published by Clerk Maxwell in 1868 and that governor is derived from a Latin corruption of κυβερνητης. We also wish to refer to the fact that the steering engines of a ship are indeed one of the earliest and best developed forms of feed-back mechanisms.” The increasing knowledge in each sector of science led to a huge diversification of scientific research, especially in a borderline sector like cybernetics applied to physiological systems. A first problem to solve was the following: let’s suppose that two groups, one with a control engineering experience and the other one with a medical background (e.g., physicians), decide to cooperate, because they strongly believe that a joined research could be useful for developing mathematical and statistical models. Usually physicians do not have enough time to study and apply advanced modelling. Wiener approached the communication between scientists belonging to different disciplines: “If a physiologist, who knows no mathematics, works together with a mathematician, who knows no physiology, the one will be unable to state his problem in terms that the other can manipulate, and the second will be unable to put the answers in any form that the first can understand. [...] The mathematician need not have the skill to conduct a physiological experiment, but he must have the skill to understand one, to criticize one, and to suggest one. The physiologist need not be able to prove a certain mathematical theorem, but he must be able to grasp its physiological significance and to tell the mathematician for what he should look.” A correct interaction in terms of a clear communication and reciprocal comprehension of the objectives of the research activity between groups with different competences is a crucial aspect in any interdisciplinary research. In 2003 at the University of Pisa it was decided to introduce a new course for undergraduate students in biomedical engineering, based on the Wiener ‘utopia’, in order to teach a novel discipline useful for helping biomedical students to communicate and cooperate effectively with physicians. We named this new course as Physiological Cybernetics, remembering the old Wiener definition. The organization of this course was a difficult task, and it required to gain experience in order to integrate so different disciplines and to produce a common language between students in biomedical engineer and physicians. At a first glance this attempt seemed to be too ambitious, because the different approaches of biomedical engineers with respect to physicians seemed incompatible and even the languages of the two groups were so different to remember the Babel tower… A great deal of effort and attention was required to produce appealing and stimulating lectures, but after many years we can affirm that this challenge is successful, especially for the enthusiastic answers of the students: their number was increasing year after year (about seventy students per year are now attending the course). A strict and trusted cooperation between different groups of physicians is growing up and several groups of physicians belonging to different medical fields are going to join us for new interactions. The aim of this chapter is to describe how the approach to physiological cybernetics has led to integrate academic lessons with research activities. To be more specific, the basic idea of Physiological Cybernetics was to search for models able to emulate physiological systems based on the feedback theory and/or the system theory. In fact, recently, the widespread use of friendly software packages for modelling, along with the development of powerful identification and control techniques has led to a renewed interest in control (Khoo, 2011; Hoppensteadt & Peskin, 2002; Cobelli & Carson, 2008) and identification (Westwick & Kearney, 2003) of physiological systems. Unfortunately physiological systems are intrinsically time variant and highly non linear. Moreover, an effective balance of the model complexity is a difficult task: low order models are usually too simple to be useful, on the other hand high order models are too complex for simulation purposes and they have too many unknown parameters to be identified. Each model selected for investigation was studied by a group of biomedical students supervised by physicians. Each model required several iterations and reformulations, due to the continuous adjustment of the research objectives, changing their final horizon, because of the gap between experimental data and theoretical models, so that the answers to the doubts and questions were continuously moving with the obtained partial results. A final goal of the research was to apply a mathematical framework for helping medical diagnostic techniques and for testing new therapeutic protocols. The procedure of model extraction followed two main pathways: the first one (pathway A) led to a formulation of a mathematical model usually based on differential equations and on an as deep as possible insight into physiological mechanisms (Marmarelis, 2004; Ottesen et al., 2004; Edelstein-Keshet, 2005; Jones et al., 2009) via a physical description of the system. The second one (pathway B) was founded on a model description based on a black-box and data-driven identification (Westwick & Kearney, 2003; Cobelli & Carson, 2008), usually leaving to stochastic models with a parametric or non-parametric structure (Ljung, 1987), depending on the a-priori knowledge of constitutive laws governing the observed system. In this paper we will describe two examples of research activity based on the Physiological Cybernetics, both of them addressed to produce a biomedical framework for predicting the effects of therapeutic actions, but following the two different pathways. The first example follows a statistical non parametric approach, the second one a mathematical model based on differential equations

Vernacular architecture and written sources: the case study of the Tronto Valley

[EN] Medieval archaeology has developed very effective instruments for investigating the smaller rural settlements and local production and construction techniques, on which the documentary sources are scarcely fluent. However, documents assure precise hints or general references to which archaeologists do not give up. In the same way, the most abundant, although indirect institutional sources, and the technical literature, from the Modern Age to the nineteenth century, are very useful to understand this kind of construction, with local materials and according to local models and practices – widespread in rural Europe until the early twentieth century. The historic villages of the upper Tronto Valley, near Ascoli Piceno, can offer a good example in a territory devastated by the 2016 earthquake in which material sources have been heavily depleted. The documents - although discontinuous - often explain constructive choices. The nineteenth-century literature describes the territory in a transformation phase, still based on the scarce local resources, and returns the mentality and the expectations of the contemporaries. Literature and documents contribute to consolidating the role of the built heritage as a historical source, highlighting both the cultural depth and the nature of housing resources that characterize the individual buildings and villages.Facchi, E.; Grimoldi, A.; Landi, AG. (2022). Vernacular architecture and written sources: the case study of the Tronto Valley. En Proceedings HERITAGE 2022 - International Conference on Vernacular Heritage: Culture, People and Sustainability. Editorial Universitat Politècnica de València. 255-262. https://doi.org/10.4995/HERITAGE2022.2022.1432125526

Resolución alternativa de conflictos y participación de los sujetos que lo integran

Los sistemas y herramientas que se utilizan para implementar la mediación, deben permitir que las partes participen en el procedimiento, comprendan las características del mismo y se manifiesten responsablemente para poder decidir sus controversias en forma autónoma. Una vez que las partes dejen de ser meros engranajes del sistema de resolución, se diluya su simple posición de “conflictivas” y se transformen en potenciales dadores de valor en relación al problema concreto y a la comunidad en la que interactúan, las mismas ocuparán una posición preponderante desde el punto de vista teórico y práctico.Systems and legal techniques used to implement mediation must allow parties to get involved in the procedure, understand its characteristics, and to act in a responsibly way in order to decide their disputes in an autonomous manner. Once the parties are no longer considered mere gears of the resolution system, their simple position of "conflicted parties" is diluted and they are transformed in potential givers of value regarding the specific conflict and the community in which they interact; only then, parties will occupy a prominent position from the theoretical and the practical point of view

Sexual violence against adolescents and young adults and parenting

Objetivo: Verificar a prevalência de adolescentes e adultos jovens vítimas de violência sexual, e a relação entre estilos parentais e a ocorrência de violência sexual. Métodos: Foram entrevistados estudantes universitários, matriculados nos cursos de Medicina, Biomedicina, Fonoaudiologia e Enfermagem, do Campus São Paulo, da Universidade Federal de São Paulo, menores de 25 anos, em 2016 e 2017. Foram utilizados os instrumentos: questionários de perfil, de comportamento e de avaliação de nível socioeconômico, para caracterizar a amostra (Abep-2014); Inventário de Estilos Parentais (IEP) – consiste em sete práticas educativas (monitoria positiva, comportamento moral, negligência, monitoria negativa, punição inconsistente, disciplina relaxada, abuso físico e psicológico) e questionário sobre exposição a eventos traumatizantes (Quesi) – com/sem abuso. O trabalho foi aprovado pelo Comitê de Ética em Pesquisa do Hospital São Paulo, Unifesp, nº 1572/05. A análise estatística inicial foi descritiva e inferencial, para aplicar a Regressão Logística Multivariada e avaliar fatores de risco para violência sexual associados aos estilos parentais. Resultados: De 861 alunos, 71 (8,24%) foram vítimas de violência sexual, 52 (73,23%) do sexo feminino. O Inventário de Estilos Parentais mostra que, em vítimas de violência sexual, há predomínio dos estilos menos protetivos (p=0,002), com maiores escores nas práticas: punição inconsistente (p=0,003), negligência (p=0,001), monitoria negativa (p=0,017) e abuso físico (p<0,001). A regressão logística mostra que a chance de um indivíduo ser vítima aumenta 11% a cada aumento de um escore de negligência, e 23,4% a cada aumento do escore de abuso físico. Quanto à monitoria positiva, a chance de um indivíduo ser vítima reduz 10% a cada aumento de um escore (p=0,009). Conclusões: Os estilos parentais influenciam diretamente a possibilidade de ocorrência de abuso sexual – monitoria positiva é fator protetor, enquanto negligência e abuso físico (punição) aumentam o risco de o indivíduo ser vítima.Objective: To verify the prevalence of adolescents and young adults victims of sexual violence and the relationship between parenting styles and the occurrence of sexual violence. Methods: We interviewed university students under 25 years old enrolled in the Medicine, Biological Sciences, Speech Therapy and Nursing courses at the São Paulo Campus of the Federal University of São Paulo, in 2016 and 2017. The following instruments were used: profile, behavioral and socio-economic level questionnaires to characterize the sample (Abep-2014); Parenting Styles Inventory (PSI) - consisting of seven educational practices (positive monitoring, moral behavior, neglect, negative monitoring, inconsistent punishment, relaxed discipline, physical and psychological abuse); questionnaire on exposure to traumatic events (Quesi) - with/without abuse. The study was approved by the Research Ethics Committee of Hospital São Paulo, Unifesp, nº 1572/05. The initial statistical analysis was descriptive and inferential in order to apply the Multivariate Logistic Regression and to evaluate risk factors for sexual violence associated with parenting. Results: Among 861 students, 71 (8.24%) were victims of sexual violence, 52 (73.23%) being female. The Parenting Styles Inventory shows that there is a prevalence among victims of sexual violence of less protective styles (p=0.002), with highest scores in the following practices: inconsistent punishment (p=0,003), neglect (p=0.001), negative monitoring (p=0.017) and physical abuse (p=0.001). Logistic regression shows that the chance of an individual becoming a victim increases by 11% with each increase in the neglect score and 23.4% with each increase in the physical abuse score. The chance of an individual being a victim is reduced by 10% with each increase of the positive monitoring score (p=0.009). Conclusions: Parenting style directly influences the occurrence of sexual abuse: positive monitoring is a protective factor, whereas physical neglect and abuse (punishment) increase the risk of being a victim

Newly Discovered Global Temperature Structures in the Quiet Sun at Solar Minimum

Magnetic loops are building blocks of the closed-field corona. While active region loops are readily seen in images taken at EUV and X-ray wavelengths, quiet Sun loops are seldom identifiable and therefore difficult to study on an individual basis. The first analysis of solar minimum (Carrington Rotation 2077) quiet Sun (QS) coronal loops utilizing a novel technique called the Michigan Loop Diagnostic Technique (MLDT) is presented. This technique combines Differential Emission Measure Tomography (DEMT) and a potential field source surface (PFSS) model, and consists of tracing PFSS field lines through the tomographic grid on which the Local Differential Emission Measure (LDEM) is determined. As a result, the electron temperature Te and density Ne at each point along each individual field line can be obtained. Using data from STEREO/EUVI and SOHO/MDI, the MLDT identifies two types of QS loops in the corona: so-called "up" loops in which the temperature increases with height, and so-called "down" loops in which the temperature decreases with height. Up loops are expected, however, down loops are a surprise, and furthermore, they are ubiquitous in the low-latitude corona. Up loops dominate the QS at higher latitudes. The MLDT allows independent determination of the empirical pressure and density scale heights, and the differences between the two remain to be explained. The down loops appear to be a newly discovered property of the solar minimum corona that may shed light on the physics of coronal heating. The results are shown to be robust to the calibration uncertainties of the EUVI instrument.Comment: Accepted for publication in The Astrophysical Journal, waiting for the full biblio inf

Static sensitivity of whole-room indirect calorimeters

Whole-room indirect calorimeters (WRIC) are accurate tools to precisely measure energy metabolism in humans via calculation of oxygen consumption and carbon dioxide production. Yet, overall accuracy of metabolic measurements relies on the validity of the theoretical model for gas exchange inside the WRIC volume in addition to experimental and environmental conditions that contribute to the uncertainty of WRIC outcome variables. The aim of this study was to quantitatively study the static sensitivity of a WRIC operated in a push configuration and located at the laboratories of the University Hospital of Pisa with the goal to identify the experimental conditions required to reach the best degree of accuracy for outcome metabolic measurements. Herein we demonstrate that achieving a fractional concentration of carbon dioxide inside the WRIC&gt;0.2% at the steady state conditions allows to obtain a relative uncertainty &lt;5% for the outcome metabolic measurement