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- ItemSomente MetadadadosA Comparative Study On Regression Approaches For Event Detection In Instagram(Universidade Federal de São Paulo (UNIFESP), 2017-11-30) Santos, Elder Donizetti Dos [UNIFESP]; Faria, Fabio Augusto [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)With the advancement of the use of web-based applications and mobile device technologies, in particular, online social networks, many approaches have been proposed in the literature using it as the source of information. Online social networks like Instagram have more than 700 million users who, together, create over 300 million new content every day. All of this data can be used, for instance, to detect real-world events. Such events can be defined as a car accident, a natural disaster, a riot, a political affair, among others. In order to do that, algorithms need to manage massive, rapidly changing and fast arriving data streams made of text, images, and videos. It also involves challenges such as the lack of a labeled database to analyze the effectiveness of applied techniques that can be reused by other researchers and the need for an approach that adapts to the constant changes in the flow of information. However, existing approaches are often either limited or not suitable for new data sources like Instagram. In this sense, this work provides contributions in the area of event detection for online social networks. As a first contribution a review on how the task of event detection has been approached by researchers since its inception in the 1990’s is presented. The second contribution is an introduction to the behavior and volume characteristics of Instagram posts modeled as time series. Then, a comparative study of different regression techniques for time series prediction is conducted by applying a preprocessing step and algorithms such as Support Vector Regression (SVR), Multilayer Perceptron (MLP), Autoregressive Integrated Moving Averages (ARIMA), Classification and Regression Trees (CART) and K-Nearest Neighbors (KNN). As a result, it is demonstrated how a simple yet efficient approach can be used to detect events in social networks. Trying to overcome some of the challenges mentioned, as a third contribution, a semi-supervised learning approach is proposed using time series correlations. Experimental studies have shown that time series from different sub-regions with similar characteristics can be used to generalize knowledge and predict the occurrence of an event. Moreover, it is demonstrated that the proposed approach is a good alternative to the Gaussian Process Regression (GPR) used in the literature since the approach based on time series correlations provides good results using much less computing resources than GPR. In addition to the main contributions cited, the entire dataset used in this thesis with more than 180 thousand manually labeled Instagram posts is publicly available.
- ItemSomente MetadadadosO Despertar Do Lótus - Terceira Coisa E Vivência De Si Em Ibn `Arabí(Universidade Federal de São Paulo (UNIFESP), 2017-07-20) Johnson, Sandra Regina Benato [UNIFESP]; Iskandar, Jamil Ibrahim [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)This work develops the concept of third thing in Ibn ‘Arabī as the sense of Identity anchored in the experience of self and daily living. Considering the simultaneous affirmation of every correlate pair, we treat the personal pronominal relations from the point of view of notions such as receptivity, transitivity, and analogy which the Sheikh establishes between the Necessary Being and the Perfect Human Being. This allows us to search for the fundamental philosophical principles of the Science of Barāzikh, here named Psicosofia, and how to actualize it as a kind of individuation’s hermeneutics and dynamics of interaction in the process of Reality.
- ItemSomente MetadadadosImproved detection of incipient vascular changes by a biotechnological platform combining post mortem MRI in situ with neuropathology(Elsevier B.V., 2009-08-15) Grinberg, Lea Tenenholz; Amaro Junior, Edson; Silva, Alexandre Valotta da [UNIFESP]; Silva, Rafael Emidio da; Sato, Joao Ricardo; Santos, Denis Dionizio dos; Pacheco, Silmara de Paula; Lucena Ferretti, Renata Eloah de; Paraizo Leite, Renata Elaine; Pasqualucci, Carlos Augusto; Teipel, Stefan J.; Flatz, Wilhelm H.; Heinsen, Helmut; Brazilian Aging Brain Study Grp; Univ Wurzburg; Universidade de São Paulo (USP); Inst Israelita Ensino & Pesquisa Albert Einstein; Universidade Federal de São Paulo (UNIFESP); Universidade Federal do ABC (UFABC); Univ Rostock; Univ MunichThe histopathological counterpart of white matter hyperintensities is a matter of debate. Methodological and ethical limitations have prevented this question to be elucidated.We want to introduce a protocol applying state-of-the-art methods in order to solve fundamental questions regarding the neuroimaging-neuropathological uncertainties comprising the most common white matter hyperintensities [WMHs] seen in aging. By this protocol, the correlation between signal features in in situ, post mortem MRI-derived methods, including DTI and MTR and quantitative and qualitative histopathology can be investigated. We are mainly interested in determining the precise neuroanatomical substrate of incipient WMHs. A major issue in this protocol is the exact co-registration of small lesion in a tridimensional coordinate system that compensates tissue deformations after histological processing.The protocol is based on four principles: post mortem MRI in situ performed in a short post mortem interval, minimal brain deformation during processing, thick serial histological sections and computer-assisted 3D reconstruction of the histological sections.This protocol will greatly facilitate a systematic study of the location, pathogenesis, clinical impact, prognosis and prevention of WMHs. (C) 2009 Elsevier B.V. All rights reserved.
- ItemSomente MetadadadosQuality of life and physical limitations in primary brain tumor patients(Springer, 2011-12-01) Gazzotti, Mariana Rodrigues [UNIFESP]; Malheiros, Suzana Maria Fleury [UNIFESP]; Alith, Marcela Batan [UNIFESP]; Nascimento, Oliver [UNIFESP]; Santoro, Ilka Lopes [UNIFESP]; Jardim, José Roberto [UNIFESP]; Vidotto, Milena Carlos [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)To correlate quality of life (QoL) and physical limitations in histological proven primary brain tumor patients using a battery of generic, disease-specific and symptom questionnaires.Thirty patients with primary brain tumors were selected from a neuro-oncology outpatient clinic. the FACT-Br Functional Assessment of Cancer Therapy-Brain (specific quality of life questionnaire for patients with brain tumors), SF-36 (generic quality of life questionnaire), HADS (anxiety and depression), and Barthel Index (functionality scale) were answered by the patients at the same interview.The Barthel index did not demonstrate correlation with any subscale of the FACT-Br questionnaire. the HADS had a negative correlation with all FACT-Br subscales and its total score. the SF-36 had a significant weak to moderate correlation with the FACT-Br questionnaire.Considering that the FACT-Br is a quick specific questionnaire, it can be a valuable and simple option in evaluating QoL in brain tumor patients with good functional capacity.
- ItemSomente MetadadadosSocio-environmental conditions and geographical variability of asthma prevalence in Northeast Brazil(Elsevier B.V., 2009-05-01) Franco, Jackeline Motta; Gurgel, Ricardo; Solé, Dirceu [UNIFESP]; Franca, Vera Lucia; Brabin, Bernard; Brazilian ISAAC Grp; Univ Fed Sergipe; Universidade Federal de São Paulo (UNIFESP); Univ LiverpoolBackground: This study aims to evaluate the association between environmental and socio-economic conditions with asthma prevalence in the eight ISAAC centres in North-East Brazil.Methods: Estimates on occurrence, severity and medical diagnoses of asthma in the previous 12 months were compared using environmental and socioeconomic indicators. Associations were assessed using simple linear regression and Pearson correlation coefficient.Results: There was no difference in asthma prevalence between centres. Active asthma prevalence increased with increasing water privation, and this would explain 62% of the observed prevalence. Median temperature increase was inversely related to active asthma (r = 0.81; p < 0.05). There was a positive association between latitude and active asthma prevalence (r = 0.82; p < 0.005), a negative association between severe asthma and yearly medium temperature (r = -0.89; p < 0.05), and a positive association with latitude (r = 0.78; p < 0.05).Conclusion: Relation between the tropical weather and high prevalence of asthma was not confirmed. There were associations with water privation and latitude. (c) 2008 SEICAP. Published by Elsevier Espana, S.L. All rights reserved.
- ItemSomente MetadadadosTwo Thyroid Stimulating Hormone assays correlated in clinical practice show disagreement in subclinical hypothyroidism patients(Pergamon-Elsevier Science Ltd, 2018) Silva, Valdelena Alessandra da; Almeida, Robson Jose de; Cavalcante, Marcele Pimenta; Pereira Junior, Lucio Antonio; Reis, Francine Machado; Pereira, Mariana Fabbris; Kasamatsu, Teresa Sayoko [UNIFESP]; Camacho, Cleber P.Thyroid Stimulating Hormone (TSH) levels are related to the pituitary gland's ability to detect thyroid hormone concentration. Many studies have analyzed the correlation between TSH and T4, demonstrating a complex system correlation. This complex system may vary among different TSH levels and patients. Objectives: The main purpose of this study is to assess the correlation and agreement of serum TSH measured with two assays in different settings. Design & methods: We evaluated healthy individuals as well as subclinical or overt hypothyroid patients. Eighty participants had TSH levels measured by Cobas Roche Elecsys 600 (Roche Diagnostics) and Abbott Architect I 2000 (Abbott Diagnostics). The TSH methods correlations were established with Pearson's correlation, and the strength of the agreement was determined by the McBride scale. The paired Student's t-test was applied to evaluate TSH values from both methods. The one-sample t-test was used to evaluate the difference between TSH values. The agreement was also assessed by a Bland-Altman plot. A regression analysis was applied to the correlation between TSH and T4. Results: There was a significant difference in TSH values measured by the two methods (p < 0.01). Our results demonstrated a poor correlation for TSH in the euthyroid (r: 0.888, p < 0.01) and the subclinical hypothyroid (r: 0.886, p < 0.01) range. The Bland-Altman plot demonstrates that the majority of the TSH values fell between the lines of equality. There were few differences in the values in the normal upper range and slightly above that range (from a TSH: 3.25 to 6.36 mUI/L). The level of correlation between TSH assays remains high in all scenarios for age (r >= 0.951), BMI (r >= 0.962), anti-TPO antibodies (r: 0.977) or levothyroxine use (r: 0.970). Conclusions: TSH measurement is essential to access thyroid function. Although the overall agreement between the methods is substantial, there was a poor agreement in the normal upper range and close above. The disagreement observed reinforces the difficulty in using different assays in clinical practice. The better correlation with fT4 and the reference range used by Cobas assay allowed the best clinical performance.