An epidemiological model with voluntary quarantine strategies governed by evolutionary game dynamics

During pandemic events, strategies such as social distancing can be fundamental to curb viral spreading. Such actions can reduce the number of simultaneous infections and mitigate the disease spreading, which is relevant to the risk of a healthcare system collapse. Although these strategies can be suggested, their actual implementation may depend on the population perception of the disease risk. The current COVID-19 crisis, for instance, is showing that some individuals are much more prone than others to remain isolated, avoiding unnecessary contacts. With this motivation, we propose an epidemiological SIR model that uses evolutionary game theory to take into account dynamic individual quarantine strategies, intending to combine in a single process social strategies, individual risk perception, and viral spreading. The disease spreads in a population whose agents can choose between self-isolation and a lifestyle careless of any epidemic risk. The strategy adoption is individual and depends on the perceived disease risk compared to the quarantine cost. The game payoff governs the strategy adoption, while the epidemic process governs the agent's health state. At the same time, the infection rate depends on the agent's strategy while the perceived disease risk depends on the fraction of infected agents. Results show recurrent infection waves, which were seen in previous epidemic scenarios with quarantine. Notably, the risk perception is found to be fundamental for controlling the magnitude of the infection peak, while the final infection size is mainly dictated by the infection rates. Low awareness leads to a single and strong infection peak, while a greater disease risk leads to shorter, although more frequent, peaks. The proposed model spontaneously captures relevant aspects of a pandemic event, highlighting the fundamental role of social strategies

A feasibility study with survival in swine model

Transrectal access still has some unsolved issues such as spatial orientation, infection, access and site closure. This study presents a simple technique to perform transcolonic access with survival in a swine model series. A new technique for NOTES perirectal access to perform retroperitoneoscopy, peritoneoscopy, liver and lymphnode biopsies was performed in 6 pigs, using Totally NOTES technique. The specimens were extracted transanally. The flexible endoscope was inserted through a posterior transmural incision and the retrorectal space. Cultures of bacteria were documented for the retroperitoneal space and intra abdominal cavity after 14 days. Rectal site was closed using non-absorbable sutures. There was no bowel cleansing, nor preoperative fasting. The procedures were performed in 6 pigs through transcolonic natural orifice access using available endoscopic flexible instruments. All animals survived 14 days without complications, and cultures were negative. Histopathologic examination of the rectal closure site showed adequate healing of suture line and no micro abscesses. The results of feasibility and safety of experimental Transcolonic NOTES potentially brings new frontiers and future wider applications for minimally invasive surgery. The treatment of colorectal, abdominal and retroperitoneal diseases through a flexible Perirectal NOTES Access (PNA) is a promising new approach

Cardiovascular assessment of diabetic patients

INTRODUCTION: Type 2 diabetes is a cardiovascular disease. The morbidity and mortality among these patients are primarily due to cardiovascular diseases. There are many guidelines regarding clinical evaluation of cardiovascular disease in those patients. Implementation of these guidelines has been an argued subject. Our objective in this paper is to describe what basal cardiovascular evaluation has been carried out at a specialized university Diabetes Center. SUBJECTS AND METHODS: Data were collected from February to October 2006 of 121 type 2 diabetes individuals who were enrolled at the Diabetes Center of Federal University of São Paulo. We analyzed the type of cardiovascular disease evaluation that they had been submitted in the year that preceded the consultation. RESULTS: We have observed a high prevalence of several other cardiovascular risk factors in this population. The cardiovascular evaluations during this period has shown 36% of the patients had not been submitted to any cardiovascular test, 17% had been submitted to resting electrocardiogram and 27% of the patients had been submitted to exercise test. Rest echocardiogram, pharmacologic stress echocardiogram, myocardial perfusion scintigraphy, and coronary angiography have been carried out in a much lesser ratio. CONCLUSION: Our data has shown the variability and limitations on boarding diagnosing of DAC in university environment patients and point us the necessity of constructing defined and directed directives for the peculiarities of the Brazilian population and health system.INTRODUÇÃO: Baseado no conhecimento atual sobre o diabetes tipo 2 (DM), considerado como um estado de doença cardiovascular, várias diretrizes surgem no intuito de sugerir uma avaliação cardiovascular rotineira nesses indivíduos, na tentativa de se detectar precocemente a doença arterial coronariana (DAC). Neste trabalho, objetivamos descrever qual avaliação cardiovascular basal fora realizada em um período de seguimento dos mesmos, dentro de um centro universitário especializado no tratamento de diabetes, adequado para a realidade brasileira. SUJEITOS E MÉTODOS: Anotamos dados clínicos do prontuário de 121 pacientes portadores de DM tipo 2 atendidos no Centro de Diabetes da Universidade Federal de São Paulo (UNIFESP) e confrontamos com o tipo de avaliação cardiovascular a que os mesmos haviam sido submetidos no ano que precedia a consulta. RESULTADOS: Observamos que na população estudada havia uma alta prevalência de outros fatores de risco cardiovasculares associados. Quanto às avaliações cardiovasculares realizadas no período, cerca de 36% dos pacientes não realizaram nenhum teste cardiológico, 17% foram submetidos ao eletrocardiograma de repouso e 27% dos pacientes foram submetidos ao teste ergométrico. Exames como ecocardiograma em repouso ou sob stress farmacológico, cintilografia de perfusão do miocárdio e cinecoronariografia foram realizados em menor proporção. CONCLUSÃO: Nossos dados mostraram a variabilidade e limitações na forma de abordagem diagnóstica de DAC de pacientes acompanhados em ambiente universitário e nos apontam para a necessidade de construir diretrizes mais bem definidas e dirigidas para as peculiaridades da população e sistema de saúde brasileiros.Universidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Centro de DiabetesUNIFESP, EPM, Centro de DiabetesSciEL

Reduction of pollutants emissions on si engines : accomplishments with efficiency increase

This paper presents an experimental study aiming to identify the means to minimize the reduction of the overall performance of a gasoline engine when employing the Exhaust- Gas Recirculation (EGR) technique that reduces NOx emissions. The increase of the compression ratio and turbocharging was evaluated as a mean to recover the original performance. The formation of pollutants and the engine performance were verified at full and partial loads. The results show that the combination of exhaust gas recirculation with turbocharger or through an increase of the compression ratio enhance the relation between the engine performance and the emission of NO. However, the turbocharger seemed to be more sensitive to the negative effects of the EGR technology

Organizational climate assessment using the paraconsistent decision method

The present study aims to show a model of organisational climate assessment through the integration of success codes and the Paraconsistent Decision Method. In this way, contributing to a previous scenario analysis that can return a more precise feedback of the organisational culture conditions of the organisation.(3ortugal

Deep reefs are not refugium for shallow-water fish communities in the southwestern Atlantic

Unidad de excelencia María de Maeztu CEX2019-000940-M1. The deep reef refugia hypothesis (DRRH) predicts that deep reef ecosystems may act as refugium for the biota of disturbed shallow waters. Because deep reefs are among the most understudied habitats on Earth, formal tests of the DRRH remain scarce. If the DRRH is valid at the community level, the diversity of species, functions, and lineages of fish communities of shallow reefs should be encapsulated in deep reefs. 2. We tested the DRRH by assessing the taxonomic, functional, and phylogenetic diversity of 22 Brazilian fish communities between 2 and 62 m depth. We partitioned the gamma diversity of shallow (30 m) into independent alpha and beta components, accounted for species' abundance, and assessed whether beta patterns were mostly driven by spatial turnover or nestedness. 3. We recorded 3,821 fishes belonging to 85 species and 36 families. Contrary to DRRH expectations, only 48% of the species occurred in both shallow and deep reefs. Alpha diversity of rare species was higher in deep reefs as expected, but alpha diversity of typical and dominant species did not vary with depth. Alpha functional diversity was higher in deep reefs only for rare and typical species, but not for dominant species. Alpha phylogenetic diversity was consistently higher in deep reefs, supporting DRRH expectations. 4. Profiles of taxonomic, functional, and phylogenetic beta diversity indicated that deep reefs were not more heterogeneous than shallow reefs, contradicting expectations of biotic homogenization near sea surface. Furthermore, pairwise beta-diversity analyses revealed that the patterns were mostly driven by spatial turnover rather than nestedness at any depth. 5. Conclusions. Although some results support the DRRH, most indicate that the shallow-water reef fish diversity is not fully encapsulated in deep reefs. Every reef contributes significantly to the regional diversity and must be managed and protected accordingly