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Sulfated polysaccharides (SPs), especially those with immunostimulant effects on shrimp and fish, are bioactive compounds with potential use in aquaculture. In this study, Pacific white shrimp (Penaeus vannamei) were fed diets containing 0%, 0.5%, 1.0%, 1.5%, or 2.0% crude extracts from the microalga Porphyridium cruentum for 30 days. After dietary supplementation, the shrimp were exposed to Vibrio alginolyticus, allowing the assessment of phenoloxidase activity (PO) and total hemocyte count (THC) pre- and post-challenge, as well as shrimp survival rates. Shrimp that received the 1.0% treatment had greater survival (90%) at 48 h post-challenge, while the 0% and 2.0% treatments had survival rates close to 63% in the same period. Furthermore, at 48 h post-challenge, THC was significantly greater (p < 0.05) in the shrimp that received crude extract supplementation compared to that in shrimp of the control group (0%). PO showed a proportional increase according to crude extract inclusion levels. Such dose-dependency in response to PO increases became significantly greater (p < 0.05) in the 2.0% treatment group compared to that in the 0% treatment group in the pre-challenge period and that in the 0% and 0.5% treatment groups in the post-challenge period. These results showed that crude extracts from P. cruentum could be considered immunostimulants by increasing the resistance of P. vannamei exposed to V. alginolyticus, potentially representing a major breakthrough for marine shrimp farming.

An experiment was conducted for eight weeks, in a BFT system, to test different strategies for using effective microorganisms (AEM) in shrimp rearing. For that, five different treatments were tested. The treatments tested were: Control (commercial feed only), AEM in the feed (addition of AEM in the commercial feed), AEM in the water (addition of AEM directly in the rearing water), AEM in the feed and in the water (addition of AEM in the feed simultaneously with the addition of AEM in the water) and MA in the feed (addition of the microbiological activator-MA in the commercial feed, without adding microorganisms to the feed and water). The use of AEM or MA, although it did not affect the growth of the animals, stimulated the digestive process of the animals, allowing the required absorption of nutrients with a smaller intestinal area. Associated with this, the presence of AME or MA stimulated the immunological parameters of the animals and reduced the presence of Vibrio in the gut of the shrimp. The association of these factors meant that the survival of the animals that received the additives in the diet was substantially higher than the animals that did not receive the additives. The AEM supplementation strategies did not differ among themselves, and the producer could opt for the strategy of lower cost and/or less complexity of use, according to each specific case.

This study introduces a novel lifetime distribution originating from the Neyman Type A distribution. We built a Neyman Type A counting process and developed a survival function. Some statistical properties of the new distribution were presented, such as the resulting humped hazard function and its convergence. An accelerated test model structure with Arrhenius law was specified, and the effects of different accelerating stresses were analyzed. The hazard function implied by the model is inversely proportional to the stress, which results in interesting features and provides an efficient approach to describe the lifespan phenomena of some engineering metals and bulbs under low temperatures. The estimation of parameters of the accelerated model by maximum likelihood, mean time to failure, and expected number of failures are discussed in the numerical experiments.

A study was conducted to test the inclusion of Aurantiochytrium sp. meal in the rearing of Penaeus vannamei grown in a clear water system and at a suboptimal temperature of 22 °C. The doses tested were 0 (control), 1, 2, 3, and 4% at a stocking density of 100 shrimp/m3. Rearing was carried out with aeration and individual heaters, and seawater temperature was controlled with a chiller. After nine weeks, shrimp were weighed and hemolymph was collected for hemato-immunological tests, and growth performance were calculated. Shrimp raised at 22 °C and fed a 1% of dietary supplementation of Aurantiochytrium sp. meal were superior in immunological parameters. After the dietary assay, a total of 42 shrimps (10.9 ± 0.06 g) per treatment were infected with White Spot Syndrome Virus (WSSV). They were orally infected with 2.6 ± 106 virus particles per g of the animal, maintained at a suboptimal temperature of 22 °C for 108 h, and acclimated to an optimal temperature of 28 °C for an additional 48 h. At 7 days post infection, surviving shrimp were collected for hemato-immunological analysis. Cumulative mortality results showed that shrimp fed diets containing 3% and 4% Aurantiochytrium sp. meal had higher survival than other treatments when challenged with WSSV.

Para o desenvolvimento de projetos de engenharia, a seleção adequada de materiais é fundamental, principalmente no que diz respeito às suas propriedades mecânicas. Em aplicações práticas, essas propriedades podem ser significativamente afetadas, devido à degradação que os materiais podem sofrer em serviço. Na exposição ao meio externo, uma degradação que pode ocorrer é aquela causada pela incidência da radiação ultravioleta (UV). Esse tipo de radiação tem energia suficiente para quebrar as cadeias dos materiais poliméricos. Assim, é importante estudar os efeitos causados pela radiação UV no comportamento desta classe de materiais. Para simular essa exposição, muitas vezes são usadas câmaras de degradação padronizadas. No entanto, esse equipamento geralmente é vendido com alto custo. Sem equipamentos que simulem a radiação ultravioleta, muitos projetos de pesquisa ficam inviáveis. Neste trabalho, pretende-se apresentar um projeto de câmara UV utilizando lâmpadas UV de baixo custo para a degradação de materiais compósitos. Além de ser mais acessível, a câmara permite uma degradação acelerada suficiente para realizar pesquisas acadêmicas experimentais sobre a degradação UV em materiais poliméricos.

Um procedimento comum na Engenharia de Confiabilidade é calcular a probabilidade de sobrevivência de um sistema em série. Utiliza-se esta formulação para calcular a confiabilidade de um equipamento com múltiplos modos de falha independentes. No entanto, perde-se a hipótese de independência entre os componentes do sistema quando se tem modos de falha correlacionados. Neste trabalho, foi utilizada uma distribuição de probabilidade bivariada, a distribuição de Gumbel, para calcular o custo de garantia de um produto sujeito a dois modos de falha não independentes. As funções densidade de probabilidade conjunta e de confiabilidade foram apresentadas e as equações de custo sob três diferentes políticas foram desenvolvidas a partir deste modelo. Um algoritmo foi desenvolvido para calcular o tempo médio para a falha supondo que a ocorrência de qualquer um dos modos de falha faça com que o cliente reivindique a garantia. Por fim, alguns exemplos numéricos e gráficos dos custos de diferentes políticas são apresentados.

ABSTRACT Nile tilapia (Oreochromis niloticus) has an opportunistic omnivorous feeding behavior and studies have demonstrated the consumption of microorganisms by the species from bioflocs, especially in the early phases of life. One may thus assume that when reared in biofloc systems, there may be a reduction in the feeding rates in the Nile tilapia nursery system when compared to the ponds. This study evaluated the effects of different feeding management options in Nile tilapia nurseries in a biofloc system. A total of 700 fingerlings (2.37 ± 0.55 g) were stocked in 20 experimental units (100 L) and inoculated with mature biofloc for the evaluation of five different feeding management options. After 49 days, it was observed that the higher feed rates caused an increase in nitrogen compounds and solids in the water, worsening the feed conversion rate. Furthermore, the excess feed supplied to the tilapia in the biofloc caused a reduction in the utilization of protein nitrogen, an increase in the liver and visceral fat, in addition to an increase in the production of solids and consumption of alkalinizer by fish biomass. On the other hand, low feeding rates cause a decrease in the growth and uniformity of the tilapia juveniles. Taking the results into consideration, it is recommended to use the feed management option proposed in treatment TC (26% below the highest feed rate) in the tilapia nursery in the biofloc system.

A ressurgência da febre amarela em vários estados brasileiros, a partir de 2017, demandou a investigação da qualidade das informações sobre a enfermidade nos textos e imagens de livros didáticos de biologia do ensino médio aprovados pelo Programa Nacional do Livro Didático 2018. As imagens foram analisadas quanto ao valor didático, segundo a Teoria Cognitiva da Aprendizagem Multimídia e os textos de acordo com a pertinência de informações sobre os Determinantes Sociais da Saúde e coerência com os Guias de Doenças Infecciosas e Parasitárias e de Vigilância em Saúde, do Ministério da Saúde. Apenas 9/26 imagens analisadas apresentaram valor didático. As informações nos textos sobre a doença eram fragmentadas, reducionistas e descontextualizadas, desconsiderando as implicações das condições socioeconômica, cultural, histórica e política, e as responsabilidades de todos no processo saúde-doença. Esses dados apontam a necessidade de atualização dos textos e melhoria da qualidade das imagens referentes a febre amarela nos livros didáticos.

Photography and photogrammetry have recently become among the most widespread and preferred visualisation methods for the representation of small objects and artefacts. People want to see the past, not only know about it; and the ability to visualise objects into virtually realistic representations is fundamental for researchers, students and educators. Here, we present two new methods, the 'Small Object and Artefact Photography' ('SOAP') and the 'High Resolution "DIY" Photogrammetry' ('HRP') protocols. The 'SOAP' protocol involves the photographic application of modern digital techniques for the representation of any small object. The 'HRP' protocol involves the photographic capturing, digital reconstruction and three-dimensional representation of small objects. These protocols follow optimised step-by-step explanations for the production of high-resolution two- and three-dimensional object imaging, achievable with minimal practice and access to basic equipment and softwares. These methods were developed to allow anyone to easily and inexpensively produce high-quality images and models for any use, from simple graphic visualisations to complex analytical, statistical and spatial analyses.

Este artigo avalia a relação entre risco de demanda e abandono contratual de concessões rodoviárias à luz de recentes alterações na regulamentação brasileira. O abandono contratual é uma flexibilidade gerencial existente em contratos desse tipo e pode agregar valor ao projeto, uma vez que o concessionário deve ser indenizado pelos investimentos realizados, independente da origem da rescisão. A teoria das opções reais foi utilizada para modelagem da opção de abandono da concessão da BR-381-262/MG/ES. A partir do fluxo de caixa esperado para o projeto, ainda em fase de licitação, e dados históricos de outras concessões sobre o risco de demanda, o modelo binomial foi aplicado para precificação da opção. Nessas condições, verificou-se que a opção agrega valor substancial ao projeto, em torno de R$ 2,6 bilhões. Este trabalho contribui para um melhor entendimento sobre a relação entre as incertezas envolvidas, o abandono do projeto e o valor agregado criado. É importante ter conhecimento prévio sobre a questão do abandono contratual para definições de valores de indenizações para estruturação de provisões.

The unrestricted consumption of fossil fuels negatively impacts the economic, social and environmental aspects, observed from a sustainable perspective. Therefore, it is necessary to develop and adopt skills that enable the monitoring and mitigation of risks to the environment. In view of this, we propose a method with multiple approaches emphasizing a three-dimensional perspective of energy consumption by diesel engines, which represent one of the main pollutants emitters in transport. As a methodology, fuzzy logic was adopted, together with a recognition system, in order to mitigate the uncertainties inherent to the applied data. The procedure was applied to the city of Rio de Janeiro, Brazil, with information collected from seven toll plazas and a radar with volumetric counting. The results indicate a good adherence of the sustainability index to real cases, allowing a better observation of changes in environmental criteria and a more efficient inspection in the application of good practices, in addition to enabling greater participation of society in the inspection and adoption of environmental criteria in transport.

Sulfated polysaccharides (SPs), especially those with immunostimulant effects on shrimp and fish, are bioactive compounds with potential use in aquaculture. In this study, Pacific white shrimp (Penaeus vannamei) were fed diets containing 0%, 0.5%, 1.0%, 1.5%, or 2.0% crude extracts from the microalga Porphyridium cruentum for 30 days. After dietary supplementation, the shrimp were exposed to Vibrio alginolyticus, allowing the assessment of phenoloxidase activity (PO) and total hemocyte count (THC) pre- and post-challenge, as well as shrimp survival rates. Shrimp that received the 1.0% treatment had greater survival (90%) at 48 h post-challenge, while the 0% and 2.0% treatments had survival rates close to 63% in the same period. Furthermore, at 48 h post-challenge, THC was significantly greater (p < 0.05) in the shrimp that received crude extract supplementation compared to that in shrimp of the control group (0%). PO showed a proportional increase according to crude extract inclusion levels. Such dose-dependency in response to PO increases became significantly greater (p < 0.05) in the 2.0% treatment group compared to that in the 0% treatment group in the pre-challenge period and that in the 0% and 0.5% treatment groups in the post-challenge period. These results showed that crude extracts from P. cruentum could be considered immunostimulants by increasing the resistance of P. vannamei exposed to V. alginolyticus, potentially representing a major breakthrough for marine shrimp farming. [ABSTRACT FROM AUTHOR]

This study introduces a novel lifetime distribution originating from the Neyman Type A distribution. We built a Neyman Type A counting process and developed a survival function. Some statistical properties of the new distribution were presented, such as the resulting humped hazard function and its convergence. An accelerated test model structure with Arrhenius law was specified, and the effects of different accelerating stresses were analyzed. The hazard function implied by the model is inversely proportional to the stress, which results in interesting features and provides an efficient approach to describe the lifespan phenomena of some engineering metals and bulbs under low temperatures. The estimation of parameters of the accelerated model by maximum likelihood, mean time to failure, and expected number of failures are discussed in the numerical experiments. [ABSTRACT FROM AUTHOR]