ABSTRACT Given the difficulty in machining of hardened steels and the complex geometries commonly observed in injection molds, besides the necessary surface quality to produce plastic parts without defects, an adequate milling strategy must be chosen, which consists in defining not only the cutting parameters and the tool, but also its trajectory. Thus, the present work focuses on investigating the influence of two different cutting strategies in milling process on the surface quality of a convex (constant curvature) surface on two types of material. The quality was evaluated through distinct roughness parameters, which were correlated to the perceived gloss and analyzed in combination with the characteristics of each material, such as hardness and microstructure. From the results obtained after the finishing operation, it was possible to verify the positive influence of the parallel tool path, which led to the lowest values of average Sa and maximum Sz roughness in both steels, VH13IM and VTMPlus, in comparison to the zig-zag tool path. The combination of low roughness values with a homogeneous topographic profile of the surface led to a higher gloss level and mirror effect.

RESUMO Dada a dificuldade em se usinar aços endurecidos e a complexidade das geometrias comumente observadas em moldes de injeção, além da qualidade da superfície necessária para a geração de peças plásticas sem defeitos, uma estratégia adequada de fresamento deve ser escolhida, o que implica na definição não apenas dos parâmetros de corte e da ferramenta, mas também de sua trajetória. Assim, o presente trabalho tem como foco a investigação da influência de duas diferentes estratégias de corte no fresamento sobre a qualidade de uma superfície convexa (de curvatura constante) em dois tipos de materiais. A qualidade foi avaliada a partir de diferentes parâmetros de rugosidade, os quais foram correlacionados com o brilho percebido e analisados juntamente às características de cada material, como dureza e microestrutura. A partir dos resultados encontrados na etapa final de acabamento, foi possível constatar a influência positiva da estratégia de corte em paralelo na obtenção dos menores valores de rugosidade média Sa e máxima Sz em ambos os aços estudados, VH13IM e VTMPlus, em comparação com a estratégia zig-zag. O conjunto de baixos valores de rugosidade com um perfil topográfico homogêneo da superfície levou a um maior brilho e grau de espelhamento.

Resumen La producción de la información, en relación con su calidad dentro de la práctica periodística en general, está supeditada a diversos criterios, como la veracidad de la fuente, la acreditación de los autores, la comprensión del texto y la relevancia de la información, entre otros indicadores. El objetivo del presente trabajo fue desarrollar una escala para evaluar la calidad de la información transmitida por medios de comunicación en Internet. Para ello, se realizaron tres etapas generales: la primera estuvo conformada por 13 estudios, donde, después de un análisis de contenido, se extrajeron las dimensiones o aspectos de la calidad de la información más frecuentemente mencionados. Posteriormente, se procedió a la detección de 35 indicadores, clasificados en 5 dimensiones; en la segunda se obtuvieron 65 ítems, a partir de la clasificación de 5 dimensiones y los 35 indicadores; en la tercera se pilotó el instrumento obtenido, el cual adquirió un formato de lista de verificación integrado por 38 ítems, y con el propósito de determinar la validez de discriminación y la confiabilidad de la escala, se aplicó a una muestra no aleatoria de 100 noticias sobre COVID-19, publicadas en sitios de internet durante el 21 de enero de 2020 y el 31 de julio de 2021. La escala desarrollada permitió evaluar la calidad de la información que se transmite por medios de comunicación electrónicos, por lo que puede ser utilizada para mejorar las prácticas de los encargados de construir el contenido informativo y divulgarlo.

Abstract Information production, regarding its quality within journalistic practice in general, is subject to various criteria, such as the veracity of the source, the accreditation of the authors, the understanding of the text, and the relevance of the information, among other indicators. The objective of the present work was to develop a scale to assess the quality of information broadcasted by media on the Internet. To achieve this goal, three general stages were carried out: the first consisted of 13 studies, where, after a content analysis, the most frequently mentioned quality information dimensions were extracted. Subsequently, 35 indicators classified in 5 dimensions were detected. In the second stage, 65 items were obtained from the classification of 5 dimensions and 35 indicators. In the third stage, the obtained instrument was piloted. The instrument acquired a checklist format made up of 38 items. To determine the discrimination validity and the reliability of the scale, it was applied to a non-random sample of 100 COVID-19 news posted on internet sites from January 21st, 2020, to July 31, 2021. The developed scale allowed the evaluation of the quality of information broadcasted by electronic media, it can therefore be used to improve the practices of those in charge of constructing the informative content and disseminating it.

ABSTRACT The fulfillment of physiological performance criteria that lead to the proper structural and functional connection between bone and implant, called osseointegration, is closely related to the surface characteristics of the biomaterial, which depend on the processes involved in its manufacture. Thus, the present work aims to expand the understanding about the influence of machining conditions on the surface integrity of commercially pure titanium grade 4 and Ti-6Al-4V ELI components submitted to the milling operation. Therefore, from a complete factorial design 2³, the type of tool, the machined titanium alloy and the cutting speed were selected as influencing factors. Three different roughness parameters were used as response variables on the surface state, namely: mean roughness (Ra), asymmetry (Rsk) and flatness (Rku) of the profile. The analysis of variance (ANOVA) indicated that the tool corresponds to the main influencing factor of this study, being significant over all response variables. The machined titanium alloy was also shown to have an influence on the results of mean roughness, while the cutting speed exhibited a significant influence both on the average roughness and on the asymmetry parameter. Precisely in relation to skewness, it is noteworthy that the different tools used produced consistently opposite results, that is: while one tool model resulted in a surface with wide peaks and deep valleys, the other model resulted in shallow and wide valleys. Thus, it is considered quite likely that the use of geometry tools and different materials will affect the biomaterial's response in terms of cell viability.

RESUMO O atendimento a critérios de desempenho fisiológicos que conduzem à devida conexão estrutural e funcional entre osso e implante, denominada osseointegração, está intimamente relacionado às características superficiais do biomaterial, as quais dependem dos processos envolvidos em sua fabricação. Assim sendo, o presente trabalho visa ampliar o entendimento acerca da influência de condições de usinagem sobre a integridade superficial de componentes em titânio comercialmente puro grau 4 e Ti-6Al-4V ELI submetidos à operação de fresamento. Para tanto, a partir de um planejamento fatorial completo 23, foram selecionados como fatores de influência o tipo de ferramenta, a liga de titânio usinada e a velocidade de corte. Foram utilizadas como variáveis de resposta sobre o estado de superfície três parâmetros de rugosidade distintos, a saber: rugosidade média (Ra), assimetria (Rsk) e achatamento (Rku) do perfil. A análise de variância (ANOVA) indicou que a ferramenta corresponde ao principal fator de influência desse estudo, sendo significativa sobre todas as variáveis de resposta. A liga de titânio usinada também se mostrou influente sobre os resultados de rugosidade média, enquanto a velocidade de corte exibiu influência significativa tanto sobre a rugosidade média quanto sobre o parâmetro de assimetria. Justamente com relação ao skewness, destaca-se que as diferentes fresas empregadas produziram resultados consistentemente opostos, isto é: enquanto um modelo de ferramenta resultou em uma superfície com picos alargados e vales profundos, o outro modelo resultou em vales rasos e largos. Dessa forma, considera-se bastante provável que a utilização de ferramentas de geometria e materiais distintos venha afetar a resposta do biomaterial em termos de viabilidade celular.

Resumen Introducción: El comportamiento de locomoción de un organismo implica la integración de aspectos como la simetría corporal, los sistemas sensorial y locomotor. Además, varios factores ecológicos parecen estar relacionados con las características de la locomoción, como la estrategia de alimentación, las tendencias migratorias, la respuesta a los depredadores y competidores y el estrés ambiental. Objetivo: Analizar el patrón general de locomoción y la influencia de la simetría corporal en la locomoción y enderezamiento de la estrella de mar Asterina stellifera. Métodos: Realizamos experimentos de laboratorio en acuarios en presencia / ausencia de corriente de agua y en superficie horizontal y vertical. Resultados: La velocidad es similar a la velocidad en otras especies de tamaño similar. Tanto la velocidad como la linealidad del desplazamiento fueron independientes del tamaño corporal individual. Una corriente de agua conduce a una velocidad de desplazamiento mayor y a trayectorias más rectas, pero no hay reotaxis: una corriente de agua no afecta el patrón de locomoción. La velocidad y la linealidad del desplazamiento fueron independientes del tamaño corporal individual. El patrón de desplazamiento aquí descrito puede ser una adaptación de organismos que presentan densas poblaciones en comunidades con alta abundancia de presas, como es el caso de A. stellifera. Conclusiones: Al igual que otros asteroides, esta especie no mostró un plano de simetría Anterior / Posterior durante la locomoción o el movimiento de enderezamiento: no tiende a la bilateralidad.

Abstract Introduction: The locomotion behavior of an organism involves the integration of aspects like body symmetry, sensory and locomotor systems. Furthermore, various ecological factors seem to be related to locomotion characteristics, such as foraging strategy, migration trends, response to predators and competitors, and environmental stress. Objective: To analyze locomotion and the influence of body symmetry in the crawling and righting movements of the sea star Asterina stellifera. Methods: We carried out laboratory experiments in aquariums in the presence/absence of water current and on a horizontal and vertical surface. Results: The speed is similar to speed in other species of similar size. Both the speed and linearity of displacement were independent of individual body size. A water current leads to faster crawling and straight paths, but there is no rheotaxis: streams do not affect locomotion. Speed and linearity of displacement were independent of individual body size. The displacement pattern described here may be an adaptation of organisms that present dense populations in communities with high prey abundance, as is the case of A. stellifera. Conclusions: Like other asteroids, this species did not show an Anterior/Posterior plane of symmetry during locomotion, or righting movement: it does not tend to bilaterality.

Resumen Introducción: Los casiduloides desempeñan un papel destacado en la historia evolutiva de los equinoides porque probablemente son el grupo ancestral de clipeasteroides. Algunas especies existentes son inquietantes y raras en el medio ambiente. En consecuencia, no existen estudios sobre su mantenimiento en laboratorio. Objetivo: Establecer un sistema de acuario eficiente para C. mitis, endémica de Brasil, para estudios ontogenéticos. Métodos: Se construyeron cuatro sistemas de acuarios, con 3 réplicas cada uno: (1) con flujo de agua de mar [F]; (2) con flujo de agua de mar e inyección de aire en el sedimento [FA]; (3) sin flujo de agua de mar pero con inyección de aire en el sedimento [A]; y (4) sin flujo de agua de mar ni inyección de aire en el sedimento [C]. Cada acuario experimental (tres por tratamiento) tenía dos adultos. Cada uno de los dos conjuntos de experimentos duró aproximadamente 60 días. Resultados: Observamos una baja mortalidad en los primeros 30 días en todos los sistemas y, después de 30 días, fue mayor en aquellos con aire bombeado al sedimento (sistema A en el primer conjunto de experimentos y sistema FA en el segundo). Conclusiones: Para experimentos de 30 días, nuestros cuatro sistemas son adecuados. Para períodos más largos, recomendamos acuarios con flujo de agua de mar y sin bombas de aire en el sedimento.

Abstract Introduction: Cassiduloids play a prominent role in echinoid evolutionary history because they probably are the ancestral group of clypeasteroids. Some extant species are brooding and rare in the environment. Consequently, there are no studies on their maintenance in the laboratory. Objective: Establish an efficient aquarium system for C. mitis, endemic to Brazil, for ontogenetic studies. Methods: Four aquarium systems were built, with 3 replicates each one: (1) with seawater flow [F]; (2) with seawater flow and air injection into sediment [FA]; (3) without seawater flow but with air injection into the sediment [A]; and (4) without both seawater flow and air injection into the sediment [C]. Each experimental aquarium (three per treatment) had two adults. Each of the two sets of experiments lasted about 60 days. Results: We observed low mortality in the first 30 days in all systems and, after 30 days, it was higher in those with air-pumped into the sediment (system A in the first set of experiments, and system FA in the second one). Conclusions: For experiments lasting 30 days, our four systems are suitable. For longer periods, we recommend aquaria with seawater flow and without air-pumps into the sediment.

Resumo Contexto O ultrassom contrastado por microbolhas (CMUS) é uma modalidade diagnóstica de acurácia bem demonstrada por estudos internacionais para seguimento de reparo endovascular do aneurisma de aorta abdominal (EVAR). Não existem, no entanto, estudos nacionais focados nesse método de seguimento. Objetivos O objetivo deste estudo foi relatar a experiência inicial com CMUS em um hospital terciário, traçando uma comparação dos achados do CMUS com o ultrassom Doppler convencional (USGD), com o intuito de verificar se a adição de contraste ao protocolo padrão de controle ultrassonográfico incorreu alteração nos achados. Métodos Entre 2015 e 2017, 21 pacientes em seguimento de EVAR foram submetidos ao USGD seguido de CMUS. Foram avaliados os achados de exame referentes à identificação de complicações, bem como à capacidade de identificação da origem da endofuga. Resultados Entre os 21 casos avaliados, 10 complicações foram evidenciadas no total: sete pacientes apresentaram endofuga (33,3%); dois pacientes apresentaram estenose em ramo de endoprótese (9,52%); e um paciente apresentou dissecção em artéria ilíaca externa (4,76%). Em 21 pacientes avaliados, o uso combinado dos métodos identificou 10 casos de complicações pós-EVAR. Em seis dos sete casos de endofugas (85,71%), o uso dos métodos combinados foi capaz de identificar a origem. O USGD isolado falhou na identificação da endofuga em dois casos (28,5%), identificando achados duvidosos em outros dois casos (28,5%), que obtiveram definição diagnóstica após associação do CMUS. Conclusões O CMUS é uma técnica de fácil execução, a qual adiciona subsídios ao seguimento de EVAR infrarrenal.

Abstract Background Microbubble contrast enhanced ultrasound (CEUS) is an accurate diagnostic method for follow-up after endovascular abdominal aortic aneurysm repair (EVAR) that has been well-established in international studies. However, there are no Brazilian studies that focus on this follow-up method. Objectives The objective of this study was to report initial experience with CEUS at a tertiary hospital, comparing the findings of CEUS with those of conventional Doppler ultrasound (DUS), with the aim of determining whether addition of contrast to the standard ultrasonographic control protocol resulted in different findings. Methods From 2015 to 2017, 21 patients in follow-up after EVAR underwent DUS followed by CEUS. The findings of these examinations were analyzed in terms of identification of complications and their capacity to identify the origin of endoleaks. Results There was evidence of complications in 10 of the 21 cases examined: seven patients exhibited endoleaks (33.3%); two patients exhibited stenosis of a branch of the endograft (9.52%); and one patient exhibited a dissection involving the external iliac artery (4.76%). In the 21 patients assessed, combined use of both methods identified 10 cases of post-EVAR complications. In six of the seven cases of endoleaks (85.71%), use of the methods in combination was capable of identifying the origin of endoleakage. DUS alone failed to identify endoleaks in two cases (28.5%) and identified doubtful findings in another two cases (28.5%), in which diagnostic definition was achieved after employing CEUS. Conclusions CEUS is a technique that is easy to perform and provides additional support for follow-up of infrarenal EVAR.

ABSTRACT Genetic variation and population structure of the sea star Coscinasterias tenuispina were investigated using allozyme electrophoresis (seven polymorphic loci out of nine sampled) at seven sites on the coast of Rio de Janeiro State. Observed values of heterozygosity's were high (HOBS = 0.31 – 0.53), although similar to those found for others marine invertebrates. Departures from Hardy-Weinberg expectations were found only for one locus in three populations. No evidence of linkage disequilibrium was found among any loci for any population. The genetic identities vary from 0.882 to 0.988. The average θ was low and insignificant statistically (θ = 0.017). Furthermore, Bayesian analysis of population partitioning showed that the highest LnP(D) value was achieved for K = 1. These results do not corroborate any effect by upwelling limiting gene flow among the analyzed populations or the hypothesis that the strong sex ratio imbalance previously recorded to Itaipu population has been maintained by asexual reproduction.

ABSTRACT. Paracentrotus gaimardi is a sea urchin reaching a maximum of 42 mm of diameter. It presents five morphotypes in sympatry characterized by their distinctive spine colors (e.g., green, black, gray, brown and rose). P. gaimardi is considered as a vulnerable species and it is included on the list of endangered species of the Brazilian coastline. In this work, allozyme electrophoresis was used to study the genetic variation among the five color morphotypes, from two different geographic locations along the coast of Rio de Janeiro State: Itaipu and Prainha, both in sympatry and allopatry. The underlying null hypothesis is that the different spine colors that define the morphotypes, represent only intraspecific variation of P. gaimardi. Eight polymorphic loci (Cat, a-Est-1, a-Est-2, Mdh, Pep, Pgi, Pgm and Xod) were assayed. Departures from Hardy-Weinberg equilibrium were tested at each locus in each morphotype from each locality. P. gaimardi species showed high levels of genetic variation (0.171-0.343) in accordance with the patterns observed for marine invertebrates. Diagnostic loci were not found among any of the five morphotypes and neither for the different geographic locations. A U-Mann Whitney test showed values significantly lower in sympatry than in allopatry for both Nei’s Geneti c Identities and 2 x 2 9 F-statistics. Furthermore, performance of AMOVA analysis considering hierarchical levels of individuals indicates that the differences in genetic variation are sorted among collection sites rather than color morphotypes.

RESUMEN. Paracentrotus gaimardi es un pequeño erizo de mar que presenta un diámetro máximo de 42 mm. Este erizo presenta cinco morfotipos en simpatría caracterizados por sus distintivas espinas coloreadas (e.g., verde, negra, gris, café y rosa). P. gaimardi es considerada una especie vulnerable y está incluida en el listado de especies en peligro de la costa brasilera. En este trabajo se usaron caracteres aloenzimáticos para estudiar la variación genética entre cinco morfotipos de color, en dos localidades geográficas diferentes de la costa del Estado de Río de Janeiro: Itaipu y Prainha, ambas en simpatría y alopatría. La hipótesis nula analizada fue: si las diferentes espinas de color definen los morfotipos, representan solamente una variación intraespecífica de P. gaimardi. Ocho loci polimórficos (Cat, a-Est-1, a-Est-2, Mdh, Pep, Pgi, Pgm and Xod) fueron examinados. Las salidas del equilibrio de Hardy-Weinberg fueron examinadas en cada locus para cada morfotipo en cada localidad. P. gaimardi presenta grandes niveles de variación genética (0,171-0,343), lo cual concuerda con los parámetros observados para invertebrados marinos. No se encontró ningún loci diagnóstico en ninguno de los cinco morfotipos para ninguna de las áreas geográficas. La prueba del U-Mann Whitney mostró valores con baja significancia en simpatría y alopatría para las identidades genéticas de Nei y la prueba de 2x2 9 F. Adicionalmente, un análisis de AMOVA sugirió niveles jerárquicos para los individuos, indicando que las diferencias genéticas están organizadas alrededor de los sitios de colecta, más que en los morfotipos de color.

OBJECTIVE: The purpose of this study was to evaluate the effectiveness of contrast-enhanced ultrasound with a second-generation contrast agent in distinguishing between occlusion and pseudo-occlusion of the cervical internal carotid artery, comparing it with that of conventional Doppler ultrasound and the gold standard, computed tomography angiography. METHOD: Between June 2006 and June 2012, we screened 72 symptomatic vascular surgery outpatients at a public hospital. Among those patients, 78 cervical internal carotid arteries were previously classified as occluded by Doppler ultrasound (without contrast). The patients were examined again with Doppler ultrasound, as well as with contrast-enhanced ultrasound and computed tomography angiography. The diagnosis was based on the presence or absence of flow. RESULTS: Among the 78 cervical internal carotid arteries identified as occluded by Doppler ultrasound, occlusion was confirmed by computed tomography angiography in only 57 (73.1%), compared with 59 (77.5%) for which occlusion was confirmed by contrast-enhanced ultrasound (p>0.5 vs. computed tomography angiography). Comparing contrast-enhanced ultrasound with Doppler ultrasound, we found that the proportion of cervical internal carotid arteries classified as occluded was 24.4% higher when the latter was used (p<0.001). CONCLUSIONS: We conclude that, in making the differential diagnosis between occlusion and pseudo-occlusion of the cervical internal carotid artery, contrast-enhanced ultrasound with a second-generation contrast agent is significantly more effective than conventional Doppler ultrasound and is equally as effective as the gold standard (computed tomography angiography). Our findings suggest that contrast-enhanced ultrasound could replace computed tomography angiography in this regard.

Fica claro que em sismos recentes, as falhas em Componentes Não Estruturais (CNE) envolvem impactos econômicos e de operações severas nos sistemas de infraestrutura. Em um estudo recente, acerca do risco sísmico, incluiu-se o estudo do comportamento dos CNEs. Neste estudo foi utilizado espectros de piso, derivados de cenários sísmicos, utilizando parâmetros de deslocamento, velocidade e aceleração, com a finalidade de entender as demandas que os CNEs poderiam estar sujeitos. Além do mais, foram utilizadas algumas técnicas para determinar as propriedades dinâmicas de alguns 9 CNEs considerados como importantes para o funcionamento de um edifício de serviços.

In recent earthquakes it has become clear that, in addition to the safety related aspects of the seismic performance of Non Structural Componets (NSC), the economic impact of the poor or marginal performance of them can be very severe. In this paper, a seismic risk assessment study conducted as part of a major project included the evaluation of the performance of NSCs. The response spectra from the earthquake scenarios are used to compute floor response spectra (acceleration, velocity and displacement) in order to gain a better understanding of the demands experienced by NSCs.

En sismos recientes ha quedado claro que las fallas en Componentes No Estructurales (CNE) involucran impactos económico y de operación severos en los sistemas de infraestructura. En un estudio reciente, acerca del riesgo sísmico, se incluyó el estudio del comportamiento de los CNEs. En este estudio se utilizaron espectros de piso, derivados de escenarios sísmicos, en donde se utilizaron parámetros de desplazamiento, velocidad y aceleración, con el fin de entender las demandas a las que podrían estar sujetas los CNEs. Se utilizaron además algunas técnicas para determinar las propiedades dinámicas de algunos CNEs considerados como importantes para el funcionamiento de un edificio de servicios.

A distribuição espacial dos bivalves e sua relação com a granulometria e os teores de matéria orgânica e silte-argila foram estudados no Saco do Céu. Obteve-se amostras de fauna e sedimento em 39 estações nos meses de janeiro e julho de 1992, utilizando-se um busca-fundo de Petersen de 0,1 m2. O sedimento variou de areia fina a areia grossa. Foram quantificadas 19 espécies sendo que 14 ocorreram nos dois períodos do ano. Os fundos de areia média e fina no verão e areia grossa no inverno apresentaram os maiores valores de diversidade e uma maior heterogeneidade estrutural. Evidenciou-se a existência de uma comunidade dominada por Anomalocardia brasiliana em fundos grossos e outra dominada por Corbula caribaea em fundos finos, ricos em matéria orgânica. Ambas distribuíram-se em contínuo, ao longo de um gradiente sedimentológico.

The spatial distribution of bivalve molluscs and its relation to granulometry and to the percentage of organic matter and silt-clay were studied in the Saco do Céu Inlet. Bivalves and samples of sediment were collected in 39 stations, in January and July 1992, using a 0.1 m2 Petersen grab. The type of sediment varied from very fine to coarse sand. Nineteen species of bivalves were quantified, 14 of which were present in the two periods of the year. The highest diversity was found in medium and fine sand in summer and in coarse sand in winter. These bottoms presented a greater structural heterogeneity. A community dominated by Corbula caribaea was distinguished in fine bottoms with relative high content of organic matter, whereas another community dominated by Anomalocardia brasiliana occurred in coarser bottoms. Both communities were distributed in continuum along a sediment gradient.