Resumo Neste trabalho foi realizado um estudo sobre o comportamento à falha do aço dos conectores de cisalhamento fabricados com recortes regulares retangulares. A equação para a capacidade resistente relacionada à falha do aço da conexão é normalmente tratada na literatura em função da espessura, da resistência ao escoamento da chapa do conector, da repetição geométrica e do fator de forma. O estudo do conector com recorte regular retangular compreendeu a dedução da equação para a falha do aço segundo o critério de von Mises e a comparação dos resultados obtidos com resultados numéricos produzidos para esse trabalho e experimentais provenientes de outros trabalhos. É apresentado o fator de forma encontrado em cada fase do estudo. Além disso, a partir dos resultados numéricos foi possível avaliar a distribuição de tensões sobre o pino de aço do conector e verificar a coerência do modelo mecânico que considera uma seção crítica retilínea e um carregamento uniformemente distribuído devido à pressão do concreto sobre o pino de aço. retangulares espessura trabalhos disso

Abstract In this work, a study was carried out on the steel failure behavior of composite dowel shear connectors with regular rectangular cutoff. The bearing capacity equation related to the steel failure is normally treated in the literature as a function of the thickness, yield strength, geometric repetition and shape coefficient. The connector with regular rectangular cutoff study comprised the deduction of the steel failure equation according to von Mises criterion and the comparison of the results obtained from numerical analysis produced for this work and experimental results from literature. The shape coefficient found in each phase of the study is presented. Furthermore, from the numerical results it was possible to evaluate the stress distribution on the steel dowel and verify the coherence of the mechanical model that considers a straight critical section and a uniformly distributed load due to the concrete pressure on the steel dowel. thickness strength presented Furthermore

Resumo Os pilares mistos preenchidos com concreto (PMPC) podem ter a seção transversal classificada em função da esbeltez local do perfil tubular como sendo: esbelta, semicompacta ou compacta. Embora já existam modelos de cálculo para determinação da força axial resistente dos PMPC com seção tubular esbelta, são escassos os estudos sobre a transferência de forças vindas das vigas conectadas a esses pilares. Este artigo tem como objetivo apresentar o processo de desenvolvimento e validação de um modelo numérico para simular o comportamento dos conectores Crestbond aplicados a (PMPC) de seção tubular esbelta, com base em resultados de experimentos realizados. O modelo numérico apresentado pode ser utilizado para o estudo e projeto da transferência de força em pilares de seção esbelta utilizando conectores em chapa conhecidos como composite dowels.

Abstract The cross-section of concrete-filled steel tube (CFST) columns is classified according to the local slenderness of the steel tube as slender, non-compact, or compact. There are analytical models to determine the axial force of locally slender CFST columns, however studies on load transfer from beams connected to these columns are scarce. This paper presents the process of the development and validation of a numerical model to simulate the behavior of Crestbond connectors applied to CFST columns with slender steel tubes, based on the results of experiments carried out. The numerical model presented can be used for the analysis and design of the load transfer in slender columns using connectors known as composite dowels.

ABSTRACT BACKGROUND: Use of the web for radiological education is an obvious application. Many computer-based teaching materials have been developed over recent years, and e-learning is becoming increasingly popular in medical schools. OBJECTIVE: To assess whether the effectiveness of distance-learning and/or e-learning, m-learning and web-based methods are equivalent to traditional methods. DESIGN AND SETTING: Systematic review of comparative studies of teaching techniques guided by Best Evidence Medical Education. METHODS: A search was carried out in the MEDLINE, EMBASE, Cochrane Library, Tripdatabase, CINAHL and LILACS online databases in April 2020, for original publications in all languages. The following MeSH terms were used: Ultrasonography; Teleradiology; Telemedicine; Education, Medical; Teaching; and Simulation Training; along with the terms e-learning, m-learning and web-based. All eligible studies were assessed using the Kirkpatrick model and Buckley's quality indicators. RESULTS: The search in the databases and a manual search resulted in 4549 articles, of which 16 had sufficient methodological quality for their inclusion. From analysis of these data, it was observed that teaching of ultrasonography using telemedicine methods is similar to the traditional method, except for venous access procedures, for which the studies did not show agreement. CONCLUSION: We found that learning via telemedicine methodologies presents great acceptance among students, besides demonstrating quality similar to the traditional method. Thus, at least at the moment, this has the capacity to serve as an important adjunct in the teaching of ultrasonography. REGISTRATION NUMBER: DOI: 10.17605/OSF.IO/CGUPA at the OPENSCIENCE Framework.

ABSTRACT BACKGROUND: Augmented reality (AR) involves digitally overlapping virtual objects onto physical objects in real space so that individuals can interact with both at the same time. AR in medical education seeks to reduce surgical complications through high-quality education. There is uncertainty in the use of AR as a learning tool for interventional radiology procedures. OBJECTIVE: To compare AR with other learning methods in interventional radiology. DESIGN AND SETTING: Systematic review of comparative studies on teaching techniques. METHODS: We searched the Cochrane Library, MEDLINE, Embase, Tripdatabase, ERIC, CINAHL, SciELO and LILACS electronic databases for studies comparing AR simulation with other teaching methods in interventional radiology. This systematic review was performed in accordance with PRISMA and the BEME Collaboration. Eligible studies were evaluated using the quality indicators provided in the BEME Collaboration Guide no. 11, and the Kirkpatrick model. RESULTS: Four randomized clinical trials were included in this review. The level of educational evidence found among all the papers was 2B, according to the Kirkpatrick model. The Cochrane Collaboration tool was applied to assess the risk of bias for individual studies and across studies. Three studies showed an improvement in teaching of the proposed procedure through AR; one study showed that the participants took longer to perform the procedure through AR. CONCLUSION: AR, as a complementary teaching tool, can provide learners with additional skills, but there is still a lack of studies with a higher evidence level according to the Kirkpatrick model. SYSTEMATIC REVIEW REGISTRATION NUMBER: DOI 10.17605/OSF.IO/ACZBM in the Open Science Framework database.

Resumo 24. A fibromatose ovariana é uma entidade benigna rara que afeta mulheres jovens, sendo caracterizada microscopicamente pela proliferação de células fusiformes e abundante matriz de colágeno. Por apresentar um quadro clínico e radiológico semelhante à de outras neoplasias mais comuns, a fibromatose ovariana deve ser diferenciada destas. No quadro clínico, a mulher apresenta dor abdominal, irregularidade menstrual e, por vezes, hirsutismo e virilização. No estudo de ressonância magnética, as lesões de fibromatose ovárica demonstram sinal hipointenso nas sequências ponderadas de T1 e T2 e o “sinal da coroa negra”. Uma vez feito o diagnóstico, deve realizar-se preferencialmente um tratamento conservador, a fim de preservar a fertilidade e função ovárica.

Abstract 19. Ovarian fibromathosis is a benign rare disorder that affects young women and is characterized microscopically by spindle cell proliferation and abundant collagen matrix. It may present similar clinical and radiological findings as other neoplasms. The clinical presentation may include abdominal pain, menstrual irregularity and possibly hirsutism and virilization. Magnetic resonance will show a hypointense signal on T1 and T2 weighted images and the black wreath sign. Once the diagnosis is established, conservative treatment with the objective of preserving fertility and ovarian function should be preferred.

ABSTRACT BACKGROUND: A positive real-time reverse-transcriptase polymerase chain reaction (RT-PCR) for SARS CoV-2, from nasopharyngeal swabs, is the current gold standard diagnostic test for this virus and has sensitivity of 60-70%. Some studies have demonstrated a significant number of false-negative RT-PCR tests while displaying significant tomographic findings, in the early days of symptoms of COVID-19. OBJECTIVE: To compare accuracy between RT-PCR and computed tomography (CT) for detecting COVID-19 in the first week of its symptoms during the pandemic. DESIGN AND SETTING: Systematic review of comparative studies of diagnostic accuracy within the Evidence-based Health Program of a federal university in São Paulo (SP), Brazil. METHODS: A systematic search of the relevant literature was conducted in the PubMed, EMBASE, Cochrane Library, CINAHL and LILACS databases, for articles published up to June 6, 2020, relating to studies evaluating the diagnostic accuracy of RT-PCR and chest CT for COVID-19 diagnoses. The QUADAS 2 tool was used for methodological quality evaluation. RESULTS: In total, 1204 patients with COVID-19 were evaluated; 1045 had tomographic findings while 755 showed positive RT-PCR for COVID-19. RT-PCR demonstrated 81.4% sensitivity, 100% specificity and 92.3% accuracy. Chest CT demonstrated 95.3% sensitivity, 43.8% specificity and 63.3% accuracy. CONCLUSION: The high sensitivity and detection rates shown by CT demonstrate that this technique has a high degree of importance in the early stages of the disease. During an outbreak, the higher prevalence of the condition increases the positive predictive value of CT. REGISTRATION NUMBER: DOI: 10.17605/OSF.IO/UNGHA in the Open Science Framework.

Resumo Introdução: o poliorquidismo é uma patologia incomum, contando cerca de 200 casos na literatura mundial. Relato de caso: relatamos um caso de poliorquidismo em um paciente do sexo masculino de 16 anos, diagnosticado por ultrassom e confirmado por ressonância magnética. Discussão: na maioria dos casos apresentados, há um testículo supranumérico, mas há relatos de mais de três, até cinco testículos, com gônadas supranuméricas em ambos os lados do escroto. O diagnóstico geralmente é feito no final da puberdade, aliás, com massa escrotal indolor ou no pronto-socorro, apresentando torção de todo o hemiscroto ou somente do testículo supranumerário, e o diagnóstico diferencial deve ser feito com cisto epididimário e espermatocele, além de outros massas extratesticulares (hidroceles, varicoceles, lipomas, tumores) e massas paratesticulares (hérnias, cálculos escrotais). Após a avaliação clínica inicial, o ultrassom é a primeira linha do exame subsidiário. A ressonância magnética é muito útil se o diagnóstico por ultrassom não for certo. Os testículos supranumerários têm as mesmas características de ressonância magnética que os testículos normais (intensidade do sinal intermediário nas imagens ponderadas em T1 e alta intensidade do sinal nas imagens ponderadas em T2).

Abstract Introduction: polyorchidism is an unusual pathology, about 200 cases in the world literature. Case report: we reported a case of polyorchidism in a 16-year-old male patient diagnosed by ultrasound and confirmed by magnetic resonance imaging. Discussion: most of the cases presented, there is a supernumerary testis, but there are reports on more than three, up to five testicles with supranumerical gonads on both sides of the scrotum. The diagnosis is usually performed in late puberty, incidentally, with a painless scrotal mass or at the emergency room, presenting a testicular torsion of the whole hemiscrotum or supernumerary testisalone, and the differential diagnosis should be made with epididymal cyst and spermatocele, besides other extra-testicular masses (hydroceles, varicoceles, lipomas, tumors.) and para-testicular masses (hernias, scrotal calculi). After the initial clinical evaluation, ultrasound is the first line subsidiary exam. Magnetic Resonance Imaging is very helpful, just in case the ultrasound diagnosis is uncertain. The supernumerary testishave the same Magnetic Resonance Imaging characteristics as the normal testes (intermediate signal intensity on T1- weighted images and high signal intensity on T2-weighted images).

Resumo O objetivo deste estudo foi determinar a acurácia diagnóstica da ultrassonografia e da eletroneuromiografia para o diagnóstico da fasciculação e comparar suas taxas de detecção. Foram realizadas buscas nas bases de dados eletrônicas Cochrane Library, MEDLINE, Embase e Lilacs, para estudos que avaliam a acurácia diagnóstica e as taxas de detecção da ultrassonografia e eletroneuromiografia. As ferramentas Quality Assessment of Diagnostic Accuracy Studies, versão 2, e RTI item bank foram utilizadas para avaliação da qualidade do método. A ultrassonografia, tanto de 10 s quanto de 30 s, apresentou taxa de detecção superior à eletroneuromiografia em todos os músculos avaliados. A avaliação da taxa de detecção por pacientes não apresentou diferença significativa entre a ultrassonografia de 10 s e 30 s. A acurácia da ultrassonografia de 10 s nos músculos foi de 70%, enquanto nos pacientes foi de 85%. Já na ultrassonografia de 30 s, a acurácia nos pacientes foi de 82%. A ultrassonografia apresentou taxas de detecção superiores à eletroneuromiografia, independentemente do tempo de sua avaliação e dos músculos avaliados.

Abstract The objective of this study was to determine the diagnostic accuracy of ultrasound and electromyography for the detection of fasciculation in patients with amyotrophic lateral sclerosis and to compare detection rates between the two methods. By searching the Cochrane Library, MEDLINE, Excerpta Medica, and Latin-American and Caribbean Health Sciences Literature databases, we identified studies evaluating the diagnostic accuracy and fasciculation detection rates of ultrasound and electromyography. The Quality Assessment of Diagnostic Accuracy Studies, version 2, and RTI item bank tools were used for the evaluation of methodological quality. Ultrasound, for 10 s or 30 s, had a higher detection rate than did electromyography in all muscles evaluated. The overall detection rate (in patients) did not differ significantly between ultrasound for 10 s and ultrasound for 30 s. The accuracy of ultrasound for 10 s was 70% in muscles and 85% in patients. The accuracy of ultrasound for 30 s was 82% in patients. Ultrasound provided detection rates superior to those achieved with electromyography, independent of the examination time and muscles evaluated.

As hérnias inguinais são uma patologia comum, com uma incidência estimada de 20 casos por 1.000 nados-vivos, sendo a forma mais comum de hérnia da parede abdominal. Este problema afecta os rapazes cerca de seis vezes mais do que as raparigas. O canal de Nuck é uma protrusão tubular do peritoneu no sexo feminino, através do anel inguinal interno, seguindo o ligamento redondo e com extensão até ao lábio vaginal. O canal de Nuck está patente em até 90% dos recém-nascidos, sendo mais prevalentes nos recém-nascidos prematuros e apresentando uma tendência para o seu encerramento espontâneo ao longo do primeiro ano de vida. Apresentamos um caso de uma menina de 6 anos com uma hérnia do canal de Nuck contendo o ovário, diagnosticada por ecografia. De acordo com a literatura, existem menos de duas dezenas de estudos ecográficos publicados que descrevem o encarceramento ovárico neste tipo de hérnias.

Inguinal hernias are a common pathology, with an estimated incidence of 20 cases per 1,000 live births, constituting the most common form of hernias of the abdominal wall. This problem affects boys about six times more often than girls. The canal of Nuck in the female is a protrusion, tubular fold of the peritoneum through the internal inguinal ring, following the round ligament and extending to the labia. The canal of Nuck is patent in up to 90% of newborns, with an increased prevalence in prematures and a tendency to spontaneously close over the first year of life. We report a case of a six-year-old girl with an ovary containing canal of Nuck hernia diagnosed by ultrasonography. According to the present literature, there are less than twenty ultrasonographic published studies which report ovary containing canal of Nuck hernias.

Abstract We report the case of a 23-year-old immunocompetent patient who presented at the emergency department of a Brazilian hospital with epigastric pain and fever. After an investigation that included a computed tomography scan and upper gastrointestinal endoscopy with biopsy, a diagnosis of mucormycosis was established. The patient exhibited favorable progress after surgery and antifungal therapy. Mucormycosis is a rare condition that usually affects immunocompromised patients, with a high mortality rate of up to 85%. Correct diagnosis and fast initiation of therapy are required to ensure improved patient prognosis.