gama pedro Gama - Academia.edu (original) (raw)

Papers by gama pedro Gama

2021 34th SIBGRAPI Conference on Graphics, Patterns and Images (SIBGRAPI), 2021

In this paper, we propose a novel approach for few-shot semantic segmentation with sparse labeled... more In this paper, we propose a novel approach for few-shot semantic segmentation with sparse labeled images. We investigate the effectiveness of our method, which is based on the Model-Agnostic Meta-Learning (MAML) algorithm, in the medical scenario, where the use of sparse labeling and few-shot can alleviate the cost of producing new annotated datasets. Our method uses sparse labels in the meta-training and dense labels in the meta-test, thus making the model learn to predict dense labels from sparse ones. We conducted experiments with four Chest X-Ray datasets to evaluate two types of annotations (grid and points). The results show that our method is the most suitable when the target domain highly differs from source domains, achieving Jaccard scores comparable to dense labels, using less than 2% of the pixels of an image with labels in few-shot scenarios.

a series of events covering a broad spectrum of systems and networks related topics. As a multi-t... more a series of events covering a broad spectrum of systems and networks related topics. As a multi-track event, ICSNC 2012 served as a forum for researchers from the academia and the industry, professionals, standard developers, policy makers and practitioners to exchange ideas. The conference covered fundamentals on wireless, high-speed, mobile and Ad hoc networks, security, policy based systems and education systems. Topics targeted design, implementation, testing, use cases, tools, and lessons learnt for such networks and systems The conference had the following tracks: • WINET: Wireless networks • HSNET: High speed networks • SENET: Sensor networks • MHNET: Mobile and Ad hoc networks • VENET: Vehicular networks • RFID: Radio-frequency identification systems • SESYS: Security systems • MCSYS: Multimedia communications systems • POSYS: Policy-based systems • PESYS: Pervasive education system We welcomed technical papers presenting research and practical results, position papers addre...

— The arising of grid platforms introduced inexpen-sive and highly available computing, storage a... more — The arising of grid platforms introduced inexpen-sive and highly available computing, storage and networking resources. Therefore, in a worldwide trend, institutions aggregate on virtual organizations, registering their resources to the grid and in return accessing a virtually limitless warehouse. This overabundance allowed the emergence of innovative application and business models, delivering the solution to several large-scale problems, as is the case of data processing, storage and sharing in CERN’s Large Hadron Collider Project. In order to allow system administrators to assure resources are employed in a coordinated and secure way, policy mechanisms need to cope with such new models and the increased complexity in resource usage management. However, current grid platforms only provide simple primitives in their authorization modules. By restricting access control mechanisms to ACLs and role-based models, they disregard powerful usage semantics, such as those which are histor...

Revista Portuguesa De Pneumologia, 2014

Arrhythmogenic right ventricular cardiomyopathy, also known as arrhythmogenic right ventricular d... more Arrhythmogenic right ventricular cardiomyopathy, also known as arrhythmogenic right ventricular dysplasia, is a condition in which myocardium is replaced by fibrous or fibrofatty tissue, predominantly in the right ventricle. It is clinically characterized by potentially lethal ventricular arrhythmias, and is a leading cause of sudden cardiac death. Its prevalence is not known exactly but is estimated at approximately 1:5000 in the adult population. Diagnosis can be on the basis of structural and functional alterations of the right ventricle, electrocardiographic abnormalities (including depolarization and repolarization alterations and ventricular arrhythmias) and family history. Diagnostic criteria facilitate the recognition and interpretation of non-specific clinical features of this disease. The authors present a case in which the diagnosis of arrhythmogenic right ventricular cardiomyopathy was prompted by the suspicion of right ventricular disease on transthoracic echocardiograp...

Political Economy - Development: Political Institutions eJournal, 2019

Portuguese Abstract: Esse livro e um dos muitos resultados de um projeto chamado Escola de Formac... more Portuguese Abstract: Esse livro e um dos muitos resultados de um projeto chamado Escola de Formacao Publica – EFp. Atualmente em sua 22a turma, a EFp e um programa de iniciacao cientifica anual para graduandos de Direito, oferecido pela Sociedade Brasileira de Direito Publico – sbdp e, desde 2015, apoiado pela FGV Direito SP e seu Grupo Publico. Nessa obra, reunimos algumas das principais pesquisas produzidas por alunos da EFp entre os anos de 2014 a 2017, em que o pano de fundo e a democracia e seus desafios juridicos. Aqui, os desafios sao de tres ordens: i) intervencao judicial na dinâmica eleitoral; ii) desafios do controle sobre a gestao publica; e iii) reformas normativas no sistema democratico. English Abstract: This book is one of many results of a project entitled School of Public Education - “Escola de Formacao Publica – EFp”. Currently in its 22nd class, EFp is an annual scientific initiation program for Law graduates offered by Brazilian society of Public Law -"Soci...

Recent investments on distribution automation (supported on telecontrol and voltage-time automati... more Recent investments on distribution automation (supported on telecontrol and voltage-time automatic function) contributed to considerable improvement of the quality of service for electric distribution in Portugal. Presently, 3.500 automated distribution devices are installed on the 60.000 km of overhead medium voltage (MV) lines. These are broadly categorized in two types: OCR1, load break switches with actuators and telecommunications that provide dispatchers remote operation and monitoring capability; OCR2, devices with fault interrupting capability, designed to operate automatically based on voltage sensors and timers. The OCR2 also has telecommunication capabilities like the OCR1. This paper provides a description of the OCR3 pilot project, presenting an overview on the implementation, the pilot network and its architecture, examples of the behaviour of the OCR3 in real situations occurred on EDP Distribuicao MV network, results and conclusions.

Arquivos Brasileiros De Cardiologia, 2010

Miocardio nao compactado (MCNC) e uma cardiopatia congenita rara, resultado da falha na compactac... more Miocardio nao compactado (MCNC) e uma cardiopatia congenita rara, resultado da falha na compactacao do miocardio, levando a persistencia de trabeculacoes numerosas e profundas, comunicantes com a cavidade ventricular. Tem como principais manifestacoes clinicas: insuficiencia cardiaca, eventos arritmicos (supraventriculares ou ventriculares) e episodios de embolismo arterial. Apresenta-se o caso de um cidadao brasileiro residente em Portugal internado por infarto agudo do miocardio, do qual resultou disfuncao sistolica severa do ventriculo esquerdo. No decorrer do estudo diagnosticou-se MCNC. Descreve-se a apresentacao clinica, ecocardiografica (bidimensional e tridimensional), imagem de ressonância magnetica nuclear (RMN) e ventriculografia. Discutem-se os criterios diagnosticos e opcoes terapeuticas.

A 69-year-old man, with a history of hypertension, dyslipidemia, stroke in 1995 and left thoracic... more A 69-year-old man, with a history of hypertension, dyslipidemia, stroke in 1995 and left thoracic-abdominal trauma in 1999 resulting in hemopneumothorax after being hit by an ox, was referred for cardiology consultation following the incidental finding on thoracic-abdominal computed tomography (CT) of an extensive area (54 mm×36 mm×20 mm) of irregular, linear calcifications located posteriorly high in the pericardial sac (Figure 1). Transthoracic and transesophageal echocardiography and thoracic CT angiography were performed to clarify whether the calcification was intravascular or extravascular and to exclude a tumor. The echocardiogram showed a rounded mass with calcified walls attached to and slightly compressing the left atrium and the coronary sulcus of the lateral and anterior walls, with apparent fibrocalcification of the myocardium of the basal segment of the lateral wall, which was thinner, hyperechogenic and akinetic (Figure 2). CT angiography showed the lesion high in the...

2019 XV Workshop de Visão Computacional (WVC), 2019

The identification of bridges in major infrastructure works is crucial to provide information abo... more The identification of bridges in major infrastructure works is crucial to provide information about the status of these constructions and support possible decision-making processes. Typically, this identification is performed by human agents that must detect the bridges into large-scale datasets, analyzing image by image, a time-consuming task. In this paper, we propose a novel tool to perform bridge detection and identification in large-scale remote sensing datasets. This tool implements a deep learning-based algorithm, the Faster R-CNN (Regions with CNN features), a technique that is the current state-of-the-art for many object detection and identification applications. Since deep training usually requires a lot of data, we also created a bridge image dataset, composed of remote sensing images from around the globe. The proposed tool was encapsulated into an ArcGIS plugin in order to facilitate its use by non-programmer users.

Arquivos Brasileiros de Cardiologia, 2016

Background: Heart failure (HF) is a highly prevalent syndrome. Although the long-term prognostic ... more Background: Heart failure (HF) is a highly prevalent syndrome. Although the long-term prognostic factors have been identified in chronic HF, this information is scarcer with respect to patients with acute HF. despite available data in the literature on longterm prognostic factors in chronic HF, data on acute HF patients are more scarce. Objectives: To develop a predictor of unfavorable prognostic events in patients hospitalized for acute HF syndromes, and to characterize a group at higher risk regarding their clinical characteristics, treatment and outcomes. Methods: cohort study of 600 patients admitted for acute HF, defined according to the European Society of Cardiology criteria. Primary endpoint for score derivation was defined as all-cause mortality and / or rehospitalization for HF at 12 months. For score validation, the following endpoints were used: all-cause mortality and / or readmission for HF at 6, 12 and 24 months. The exclusion criteria were: high output HF; patients with acute myocardial infraction, acute myocarditis, infectious endocarditis, pulmonary infection, pulmonary artery hypertension and severe mitral stenosis. Results: 505 patients were included, and prognostic predicting factors at 12 months were identified. One or two points were assigned according to the odds ratio (OR) obtained (p < 0.05). After the total score value was determined, a 4-point cutoff was determined for each ROC curve at 12 months. Two groups were formed according to the number of points, group A < 4 points, and group B = 4 points. Group B was composed of older patients, with higher number of comorbidities and predictors of the combined endpoint at 6, 12 and 24 months, as linearly represented in the survival curves (Log rank). Conclusions: This risk score enabled the identification of a group with worse prognosis at 12 months.

Acta Médica Portuguesa, 2016

Adults with chronic immunosuppressive conditions are at an increased risk for Streptococcus agala... more Adults with chronic immunosuppressive conditions are at an increased risk for Streptococcus agalactiae endocarditis, which is typically characterized by acute onset, presence of large vegetations, rapid valvular destruction and frequent complications. We report a rare case of a 74 years old man presenting with fever, renal infarction, ischemic stroke and uveitis. Infective endocarditis was diagnosed and Streptococcus agalactiae was isolated in blood cultures. A multiple myeloma Ig G-K was also diagnosed. The infective endocarditis was successfully treated with a course of benzylpenicillin and gentamicin. The authors highlight the severity of vascular embolic disease present in this case and the diagnostic challenge. They also intend to remind about the association between Streptococcus agalactiae endocarditis and chronic diseases, despite its low reported prevalence.

Geologia Colombiana, Jan 20, 2012

Revista Portuguesa De Cardiologia, 2009

Journal of Investigative Medicine, 2007

Cardiac involvement is found in approximately 5% of patients with sarcoidosis. The course of the ... more Cardiac involvement is found in approximately 5% of patients with sarcoidosis. The course of the disease is variable, ranging from benign arrhythmias to high-degree heart block or sudden death, and diagnosis is difficult. Endomyocardial biopsy can confirm the diagnosis but the diagnostic yield of the procedure is low because of the uneven distribution of the granulomatous process. Cardiac sarcoidosis should be presumed in patients with known sarcoidosis who develop arrhythmias, conduction disease, heart failure or ECG abnormalities. The authors present a case report and brief review of cardiac sarcoidosis.

La sección está compuesta por 109 m de biomicritas wackestone, lodolitas carbonosas fosilíferas y... more La sección está compuesta por 109 m de biomicritas wackestone, lodolitas carbonosas fosilíferas y liditas diagenéticas, con intercalaciones de láminas de posibles bentonitas, las cuales son agrupadas en dos segmentos: el inferior (70 m), que se divide en los niveles I, II y III y el superior (39 m), que incluye los niveles IV y V. La bioestratigrafía de la Formación La Frontera, permite establecer una edad Cenomaniano tardío-Turoniano medio. Históricamente y desde el punto de vista litoestratigráfico, la Formación La Frontera ha sido interpretada de diversas maneras, por lo que una revisión a este nivel se hace necesaria. La secuencia carece de complicaciones estructurales, presenta una buena exposición de sus contactos inferior, con la Formación Pacho, y superior, con la Formación Conejo y en ella aflora toda la sucesión estratigráfica equivalente a la descrita en la literatura. Con base en lo anterior y teniendo en cuenta que no existe una adecuada designación y descripción del estratotipo de la unidad, ubicado

El estudio preliminar de una serie de afloramientos del Cretácico inferior en los sectores de Vil... more El estudio preliminar de una serie de afloramientos del Cretácico inferior en los sectores de Villa de Leyva, y Vélez-Chipatá (Boyacá-Santander, Colombia) permitió la identificación de una proporción elevada del foraminífero bentónico calcáreo Epistomina caracolla (ROEMER), en niveles de composición bioesparítica para la parte media de la Formación Paja. Los foraminíferos bentónicos en todos estos puntos se encuentran asociados a los géneros de amonoideos Pseudohaploceras, Pedioceras, Nicklesia, Buergliceras y Karsteniceras, cuya presencia conjunta con los foraminíferos indica una edad de Barremiano inferior. El análisis micropaleontológico y petrográfico de estos niveles calcáreos muestra características muy similares y la presencia homogénea de la asociación fósil encontrada hace que se consideren estos niveles calcáreos como un "bioevento" con posible relevancia estratigráfica dentro de la Formación Paja. La baja diversidad en los foraminíferos bentónicos podría indicar un ambiente anóxico, fuertemente conectado a la línea de costa y a condiciones hipersalinas. El hecho de que la macrofauna se encuentre dispuesta en forma caótica ayuda a soportar esa conclusión.

Revista Portuguesa de Cardiologia, 2015

A utilização de sistemas de computação em grelha permitiu revolucionar a partilha e optimização d... more A utilização de sistemas de computação em grelha permitiu revolucionar a partilha e optimização de recursos heterogéneos entre entidades distintas. Em paralelo, estes sistemas introduziram também inúmeras vulnerabilidades de segurança, associadas aos sistemas distribuídos no geral, e aos sistemas em grelha em particular, a queé necessário fazer face. Apresentamos neste artigo uma análise dos aspectos de segurança que consideramos mais relevantes para sistemas de computação em grelha, como a autenticação dos utilizadores e recursos, a autorização nos acessos, a delegação de privilégios e a comunicação entre nós. Complementamos ainda essa análise com a avaliação das arquitecturas de segurança das plataformas existentes, quando aplicável. Pretendemos contribuir para a consciencialização da importância da segurança nas plataformas de computação em grelha, contribuindo para a evolução deste tipo de sistemas. Globus Certificados x509 Consh Mecanismos Locais Gridbank Certificados x509 EDG Certificados x509 Nordugrid Certificados x509 JXTA Certificados x509 Crisis Certificados x509 Condor Certificados x509 NASA IPG Certificados x509 Legion Certificados x509 Alchemi Username / password Unicore Certificados x509 IGENV Certificados x509

Revista portuguesa de cardiologia : orgão oficial da Sociedade Portuguesa de Cardiologia = Portuguese journal of cardiology : an official journal of the Portuguese Society of Cardiology, 2009

Left ventricular noncompaction (LVNC) is a rare congenital disease caused by an arrest in normal ... more Left ventricular noncompaction (LVNC) is a rare congenital disease caused by an arrest in normal myocardial embryogenesis, leading to persistence of numerous prominent trabeculations that communicate with the left ventricle. It was first described as a congenital condition affecting children, but several cases have been reported of late presentation. The main clinical manifestations are congestive heart failure, arrhythmias (supraventricular or ventricular) and systemic embolism. We present the case of a 51-year-old patient brought to our emergency department after an episode of symptomatic ventricular flutter requiring electrical cardioversion. Two-dimensional echocardiography with color Doppler suggested the diagnosis and the three-dimensional echocardiogram revealed the deep trabeculations typical of LVNC.