Automatic Development and Adaptation of Concise Nonlinear Models for System Identification

Mathematical descriptions of natural and man-made processes are the bedrock of science, used by humans to understand, estimate, predict and control the natural and built world around them. The goal of system identification is to enable the inference of mathematical descriptions of the true behavior and dynamics of processes from their measured observations. The crux of this task is the identification of the dynamic model form (topology) in addition to its parameters. Model structures must be concise to offer insight to the user about the process in question. To that end, this dissertation proposes three methods to improve the ability of system identification to identify succinct nonlinear model structures. The first is a model structure adaptation method (MSAM) that modifies first principles models to increase their predictive ability while maintaining intelligibility. Model structure identification is achieved by this method despite the presence of parametric error through a novel means of estimating the gradient of model structure perturbations. I demonstrate MSAM\u27s ability to identify underlying nonlinear dynamic models starting from linear models in the presence of parametric uncertainty. The main contribution of this method is the ability to adapt the structure of existing models of processes such that they more closely match the process observations. The second method, known as epigenetic linear genetic programming (ELGP), conducts symbolic regression without a priori knowledge of the form of the model or its parameters. ELGP incorporates a layer of genetic regulation into genetic programming (GP) and adapts it by local search to tune the resultant model structures for accuracy and conciseness. The introduction of epigenetics is made simple by the use of a stack-based program representation. This method, tested on hundreds of dynamics problems, demonstrates the ability of epigenetic local search to improve GP by producing simpler and more accurate models. The third method relies on a multidimensional GP approach (M4GP) for solving multiclass classification problems. The proposed method uses stack-based GP to conduct nonlinear feature transformations to optimize the clustering of data according to their classes. In comparison to several state-of-the-art methods, M4GP is able to classify test data better on several real-world problems. The main contribution of M4GP is its demonstrated ability to combine the strengths of GP (e.g. nonlinear feature transformations and feature selection) with the strengths of distance-based classification. MSAM, ELGP and M4GP improve the identification of succinct nonlinear model structures for continuous dynamic processes with starting models, continuous dynamic processes without starting models, and multiclass dynamic processes without starting models, respectively. A considerable portion of this dissertation is devoted to the application of these methods to these three classes of real-world dynamic modeling problems. MSAM is applied to the restructuring of controllers to improve the closed-loop system response of nonlinear plants. ELGP is used to identify the closed-loop dynamics of an industrial scale wind turbine and to define a reduced-order model of fluid-structure interaction. Lastly, M4GP is used to identify a dynamic behavioral model of bald eagles from collected data. The methods are analyzed alongside many other state-of-the-art system identification methods in the context of model accuracy and conciseness

Analysis of Score-Level Fusion Rules for Deepfake Detection

Deepfake detection is of fundamental importance to preserve the reliability of multimedia communications. Modern deepfake detection systems are often specialized on one or more types of manipulation but are not able to generalize. On the other hand, when properly designed, ensemble learning and fusion techniques can reduce this issue. In this paper, we exploit the complementarity of different individual classifiers and evaluate which fusion rules are best suited to increase the generalization capacity of modern deepfake detection systems. We also give some insights to designers for selecting the most appropriate approach

REAÇÕES DE CRIANÇAS E ADOLESCENTES SUBMETIDOS À ANALGESIA TÓPICA LOCAL NA PUNÇÃO VENOSA PERIFÉRICA.

El objeto del estudio es la reacción del cliente sometido a analgesia tópica local en el período anterior, durante y después de la punción venosa periférica. El objetivo es conocer estas reacciones y evaluar la eficacia de la medicina. Fue utilizado el método cualitativo y los instrumentos para la producción de los datos fueron la observación participante y la entrevista semiestructurada. El lugar fue el Hospital de Día Pediátrico en el Hospital dos Servidores do Estado. Los sujetos son 12 clientes de 5 a 18 años que con sus cuidadores habían sido informados de las etapas del procedimiento. Antes de la punción, el 84% de los sujetos dijeron que tenían miedo del procedimiento, el 16% había demostrado tranquilidad y había dicho no sentir miedo. Durante la punción el 58% había cooperado, mientras que el 42% había necesitado la contención física por la madre. Después del procedimiento, 100% hablaron no haber sentido dolor. Se concluye que tiene eficacia la analgesia, pero que los períodos pre y trans-punción habían sido traumáticos. El razonamiento inductivo nos ha hecho reflexionar sobre la necesidad de evaluar los factores causales que habían llevado a niños a la sensación de miedo y a necesitar de la contención física por la madre, incluso después de haber recibido las explicaciones de la enfermera sobre el procedimiento.O objeto de estudo é a reação do cliente submetido à analgesia tópica local, nos períodos pré, trans e pós-punção venosa periférica. O objetivo é conhecer estas reações e avaliar a eficácia do medicamento. Foi utilizada a abordagem qualitativa e os instrumentos para produção dos dados foram a observação participante e entrevista semi-estruturada. O cenário foi o Hospital Dia Pediátrico do Hospital dos Servidores do Estado. Os sujeitos são 12 clientes de 5 à 18 anos que com seus cuidadores foram informados sobre as etapas do procedimento. Antes da punção 84% dos sujeitos verbalizaram medo do procedimento, 16% demonstraram tranqüilidade e disseram não sentir medo. Durante a punção 58% cooperaram, enquanto 42% necessitaram de contenção física pela mãe. Após o procedimento 100% verbalizaram não terem sentido dor. Conclui-se que há eficácia na analgesia, mas que os períodos pré e trans-punção foram traumáticos. O raciocínio indutivo nos fez refletir que há necessidade de avaliarmos os fatores causais que levaram as crianças a sentir medo e necessitarem de contenção física pela mãe, mesmo após receberem as explicações da enfermeira sobre o procedimento

Serafino Zappacosta: An Enlightened Mentor and Educator

With this article, the authors aim to honor the memory of Serafino Zappacosta, who had been their mentor during the early years of their career in science. The authors discuss how the combination of Serafino Zappacosta's extraordinary commitment to teaching and passion for science created a fostering educational environment that led to the creation of the “Ruggero Ceppellini Advanced School of Immunology.” The review also illustrates how the research on the MHC and the inspirational scientific context in the Zappacosta's laboratory influenced the authors' early scientific interests, and subsequent professional work as immunologists

Clinical and Epidemiological Study on Tubercular Uveitis in a Tertiary Eye Care Centre in Italy

PURPOSE: To describe frequency, clinical characteristics, and visual prognosis of tubercular uveitis (TBU) in a nonendemic country. METHODS: We retrospectively reviewed 3743 charts of patients with endogenous uveitis visited from 2008 to 2018 at a tertiary referral centre in Rome, Italy. We included immunocompetent patients with diagnosis of TBU. Patients were divided in two groups: patients with history of uveitis without a previous diagnosis of TBU (group A) and patients at their first episode of TB uveitis (group B). RESULTS: TBU was diagnosed in 28 (0.75%) out of 3743 patients. Twelve (42.9%) patients came from tuberculosis endemic areas. All patients received specific antitubercular treatment (ATT) and were evaluated for a mean follow-up of 3.2 ± 2.9 years. Group A showed a greater number of ocular complications when compared with group B. ATT was effective in reducing the frequency of recurrences of uveitis in patients of group B. CONCLUSION: Intraocular inflammation can be the first manifestation of tuberculosis. Our data highlight that early diagnosis and specific treatment of TBU may allow to decrease recurrences and to improve visual outcomes

Superdense massive galaxies in the Nearby Universe

Superdense massive galaxies (r_e~1 kpc; M~10^{11} Msun) were common in the early universe (z>1.5). Within some hierarchical merging scenarios, a non-negligible fraction (1-10%) of these galaxies is expected to survive since that epoch retaining their compactness and presenting old stellar populations in the present universe. Using the NYU Value-Added Galaxy Catalog from the SDSS Data Release 6 we find only a tiny fraction of galaxies (~0.03%) with r_e<1.5 kpc and M_*>8x10^{10} Msun in the local Universe (z<0.2). Surprinsingly, they are relatively young (~2 Gyr) and metal-rich ([Z/H]~0.2). The consequences of these findings within the current two competing size evolution scenarios for the most massive galaxies ("dry" mergers vs "puffing up" due to quasar activity) are discussed.Comment: Accepted for publication in ApJ Letters; 3 figure

High-density neutrophils in MGUS and multiple myeloma are dysfunctional and immune-suppressive due to increased STAT3 downstream signaling

To understand neutrophil impairment in the progression from MGUS through active MM, we investigated the function of mature, high-density neutrophils (HDNs), isolated from peripheral blood. In 7 MM, 3 MGUS and 3 healthy subjects by gene expression profile, we identified a total of 551 upregulated and 343 downregulated genes in MM-HDN, involved in chemokine signaling pathway and FC-gamma receptor mediated phagocytosis conveying in the activation of STAT proteins. In a series of 60 newly diagnosed MM and 30 MGUS patients, by flow-cytometry we found that HDN from MM, and to a lesser extend MGUS, had an up-regulation of the inducible FcγRI (also known as CD64) and a down-regulation of the constitutive FcγRIIIa (also known as CD16) together with a reduced phagocytic activity and oxidative burst, associated to increased immune-suppression that could be reverted by arginase inhibitors in co-culture with lymphocytes. In 43 consecutive newly-diagnosed MM patients, who received first-line treatment based on bortezomib, thalidomide and dexamethasone, high CD64 could identify at diagnosis patients with inferior median overall survival (39.5 versus 86.7 months, p = 0.04). Thus, HDNs are significantly different among healthy, MGUS and MM subjects. In both MGUS and MM neutrophils may play a role in supporting both the increased susceptibility to infection and the immunological dysfunction that leads to tumor progression

The prognostic value of the myeloid-mediated immunosuppression marker Arginase-1 in classic Hodgkin Lymphoma

Neutrophilia is hallmark of classic Hodgkin Lymphoma (cHL), but its precise characterization remains elusive. We aimed at investigating the immunosuppressive role of high-density neutrophils in HL