Experimental Demonstration of Dual Polarization Nonlinear Frequency Division Multiplexed Optical Transmission System

Multi-eigenvalues transmission with information encoded simultaneously in both orthogonal polarizations is experimentally demonstrated. Performance below the HD-FEC limit is demonstrated for 8-bits/symbol 1-GBd signals after transmission up to 207 km of SSMF

Collision of ductal adenocarcinoma and neuroendocrine tumor of the pancreas: a case report and review of the literature

Background: Simultaneous occurrence of exocrine and neuroendocrine tumors of the pancreas is very infrequent. We report a patient with an endocrine tumor in the pancreatic-duodenal area and extensive exocrine carcinoma involving the whole pancreas. Case presentation: A 69-year-old woman was hospitalized in May 2016 for epigastric pain and weight loss. Her past medical history revealed an undefined main pancreatic duct dilation that was subsequently confirmed at CT scan (23 mm) and endoscopic ultrasound. There was no evidence of pancreatic masses, but the cephalic portion of the main pancreatic duct presented hypoechoic nodules. A diagnosis of the main-duct intraductal papillary mucinous neoplasm was made, and the patient underwent total pancreatectomy. Pathological examination showed a collision tumor constituted by a ductal adenocarcinoma involving the whole pancreas and a neuroendocrine tumor located in the duodenal peripancreatic wall and the head of the pancreas. There was one peripancreatic lymph node metastasis from the ductal adenocarcinoma and eight node metastases from the neuroendocrine tumor. These findings suggested a diagnosis of collision of neuroendocrine and ductal adenocarcinomas of the pancreas. The postoperative course was uneventful. Conclusions: The coexistence of pancreatic endocrine and exocrine tumors is very uncommon. When present, problems in differential diagnosis may arise between mixed exocrine-endocrine carcinoma or the collision of separate tumors

Dual polarization nonlinear Fourier transform-based optical communication system

New services and applications are causing an exponential increase in internet traffic. In a few years, current fiber optic communication system infrastructure will not be able to meet this demand because fiber nonlinearity dramatically limits the information transmission rate. Eigenvalue communication could potentially overcome these limitations. It relies on a mathematical technique called "nonlinear Fourier transform (NFT)" to exploit the "hidden" linearity of the nonlinear Schr\"odinger equation as the master model for signal propagation in an optical fiber. We present here the theoretical tools describing the NFT for the Manakov system and report on experimental transmission results for dual polarization in fiber optic eigenvalue communications. A transmission of up to 373.5 km with bit error rate less than the hard-decision forward error correction threshold has been achieved. Our results demonstrate that dual-polarization NFT can work in practice and enable an increased spectral efficiency in NFT-based communication systems, which are currently based on single polarization channels

Iniciativa de arquivos abertos como nova forma de comunicação científica

The Great innovations that information and communication technologies brought revolutionized possibilities of communication among scientists, above all, to disseminate and share results of researches. A group of researchers from United States and Europa has been developed a set of standard, tecnologies solutions and ideals to promote open access, to make feasible and to stimulate web publishing through models of business and self-supporting. This "subversive" proposal, named of The Open Archives Initiative – OAI, stimules wide distribution and visibility of the papers deposits there without fee to promote fair use in benefit of science, on the contrary commercial periodicals, in which scientist must to pay to use information. From among the models developed through OAI, will be distached eprints repositories, that is based on self-archiving, tranparency in spontaneous peer review and constitution of new versions to the same paper through those peer reviews. Will be present Arena Cientifica, a proposal of discipline repository to Communications Sciences based in this specific model from OAI. This projetc is a result of research of doctor thesis

Resoluçâo de problemas matemáticos no ensino fundamental

Neste trabalho, apresentamos os resultados do primeiro ano de uma pesquisa experimental e longitudinal que investiga a resolução de problemas matemáticos por estudantes dos anos iniciais do Ensino Fundamental de uma escola pública no sul do Brasil. O objetivo é buscar o aprimoramento no desempenho dos alunos dos anos iniciais do Ensino Fundamental em resolução de problemas matemáticos aditivos e multiplicativos, qualificando a prática docente a partir de estratégias de formação continuada de seus professores. A comparação do desempenho dos estudantes no pré-teste e no pós-teste evidenciou avanços significativos em todas as séries, exceto no 6º ano do Ensino Fundamental

Estratégias para implementação de repositórios da UNIRIO

This paper refers to the project of creation of repositories UNIRIO. It aims to describe the process of developing this initiative by the theoretical reference and the applied methodologies. The project will be implemented by three digital repositories: institutional, disciplinary and experimental, which will constitute a fertile field for study, research and development of professional practices, as well academic and outreach activities that allows high level studies

From the movements to the movement: The importance of the social, popular and syndical movements in the constitution of the teacher's political identity

Este artigo resulta de pesquisa que investigou a importância dos movimentos social, político e sindical na constituição da identidade política docente. Respaldada na abordagem qualitativa, o trabalho apoiou-se no levantamento bibliográfico e documental, em entrevistas narrativas e observações-participantes. A questão que fomentou o estudo foi: Como a formação, dentro dos movimentos social, popular e sindical, associada à formação sindical, às greves e às paralisações, contribuiu para a constituição da identidade política docente? Constatou-se que a constituição política dos professores entrevistados se iniciou nos movimentos social e popular e amadureceu no movimento sindical. Tal fato, aliado à práxis, possibilitou-lhes a luta e a defesa por uma educação pública com qualidade socialThe article results from a research that investigated the importance of social, political and syndical movements in the constitution of teacher’s political identity. Based on qualitative approach, this paper is supported by a bibliographic research, interviews and participant-observations. The question here is how education background inside social, popular and syndical movements, associated to syndical education, to strikes and to stoppages contributed to the constitution of the teacher’s political identity? It can be concluded that the interviewers’ political background began in the social and popular movement and matured in the syndical movement. That fact associated to praxis resulted in the fight and defense of a public education with social qualit