Topological phases of graphene-Kagome systems.

The growing skill in the synthesis processes of new materials has intensified the interest in exploring the properties of systems modeled by more complex lattices. Two-dimensional super-honeycomb lattices, have been investigated in metallic organic frameworks. They turned out as a significant route to the emergence of localized electronic responses manifested as flat bands in their structure with topological isolating behavior. A natural inquiry is a complete analysis of their topological phases in the presence of electronic correlation effects. Here we analyze the electron-electron correlation effects via Hubbard mean-field approximation on the topological phases of 2D and quasi-1D graphene-Kagome lattices. The 2D spin conductivity phase's diagrams describe metallic, trivial, and topological insulating behaviors, considering different energy coupling and electronic occupations. Our results pave the way to smart-engineered nanostructured devices with relevant applications in spintronics and transport responses.

Insulinoma: A retrospective study analyzing the differences between benign and malignant tumors.

BACKGROUND/OBJECTIVES: Insulinoma is a rare pancreatic tumor and, usually, a benign disease but can be a malignant one and, sometimes, a highly aggressive disease. The aim of this study was to determine differences between benign and malignant tumors. METHODS: Retrospective study of 103 patients with insulinoma treated in a tertiary center. It was analyzed demographic, clinical, laboratory, localization and histologic analysis of tumor and follow up data of subjects in order to identify differences between individuals benign and malignant disease. RESULTS: Almost all patients (87%) had a benign tumor and survival rates of 100% following pancreatic tumor surgery. Those with malignant tumors (13%) have a poor prognosis, 77% insulinoma-related deaths over a period of 1-300 months after the diagnosis with a survival rate of 24% in five years. The following factors are associated with an increased risk of malignant disease: duration of symptoms < 24 months, fasting time for the occurrence of hypoglycemia < 8 h, blood plasma insulin concentration ≥ 28 µU/mL and C-peptide ≥ 4.0 ng/mL at the glycemic nadir and tumor size ≥ 2.5 cm. CONCLUSIONS: Our data help to base the literature about these tumors, reinforcing that although insulinoma is usually a single benign and surgically treated neoplasia, the malignant one is difficult to treat. We highlight the data that help predict a malignancy behavior of tumor and suggest a long follow up after diagnosis in these cases.

Emergency planning for hazardous industrial areas: a Brazilian case study.

One of the characteristics of modern industrial development is the emergence of a new typology of accidents whose effects can be spread, in space as well as in time, well beyond the borders of the installations where they occur, sometimes impacting the local population and the environment in a catastrophic fashion. This is the result of a number of factors that have changed the risk profile of modern industrial activities. For a number of reasons, the developing countries have proved to be more vulnerable to industrial disasters. Three of the most catastrophic industrial accidents--Bhopal, San Juan de Ixhuatepec, and Cubatão--occurred in developing countries, claiming thousands of lives. During the 1970s and 1980s the higher degree of public visibility of industrial hazards as a result of serious accidents, led to the creation, especially in the more industrialized countries, of regulations for greater control over industrial activities, either by means of new laws or by updating existing legislation. Some of these regulations were designed to improve the response to accidents with potential impacts outside the industrial sites. This article attempts to describe the current status and identify the shortcomings of off-site emergency planning for hazardous industrial areas in Brazil. The most important problems are the lack of specific legislation and the absence of awareness and active participation of public authorities. The experience of an off-site emergency planning process for a Brazilian industrial area is presented. This experience illustrates how difficult it is to prepare and implement emergency planning processes in an industrializing country.

[Surgical findings in 260 cases of basilar impression and/or Arnold-Chiari malformation]. / Achados cirúrgicos em 260 casos de impressão basilar e/ou malformação de Arnold-Chiari.

The surgical findings observed in a series of 260 patients with craniovertebral anomaly are presented. There were 29 (11.1%) patients only with basilar impression, 18 (6.9%) cases of pure Arnold-Chiari malformation and 213 (81.9%) cases of basilar impression associated with Chiari malformation. The surgical findings on bone, dura-mater, nervous tissue and blood vessels of this region are reported.