1,317 research outputs found
Mathematical modeling of bovine brucellosis control by vaccination
As fêmeas bovinas, por sua importância na transmissão e na manutenção da brucelose, constituÃram o alvo dos inquéritos do Programa Nacional de Controle e Erradicação da Brucelose e da Tuberculose Animal. Com base em informações obtidas em unidades federativas onde foram realizados inquéritos sorológicos e observadas prevalências de animais acima de 2%, elaborou-se um modelo para simular a dinâmica da brucelose em rebanhos bovinos formados exclusivamente por fêmeas, analisando o efeito de estratégias de vacinação. Para baixa cobertura vacinal, da ordem de 30%, o tempo para reduzir a prevalência a 2%, valor adotado como referência, pode ser longo, aproximando-se do dobro do tempo necessário para uma cobertura mais alta, de 90%. De acordo com o modelo, o tempo para reduzir a prevalência a 1% ou 2%, que permitam passar à fase de erradicação, pode chegar a uma década. Recomenda-se a intensificação do esforço para a vacinação de fêmeas, procurando atingir alta cobertura vacinal.Due to the important role played by female bovines in the transmission and maintenance of brucellosis, they were the target of the serological surveys of the Brazilian National Program for the Control and Eradication of Bovine Brucellosis and Tuberculosis. Based on the information obtained in Brazilian states, where the serological surveys were carried out and prevalences higher than 2% were observed, a model to simulate the dynamics of brucellosis in herds of female bovines was developed to analyze the effects of vaccination strategies. For low vaccination coverage (around 30%), the time to reduce the prevalence to 2%, adopted as a reference, may be long, approximately twice as long as the time observed for a higher coverage (90%). According to the model, the time to reduce the prevalence to levels of 1% or 2%, adequate to start the eradication phase, may reach a decade. It is recommended an intensification of the effort to vaccinate females, aiming at attaining high vaccination coverage.FAPESPCNPqMAPA Ministério da Agricultura, Pecuária e Abasteciment
Prediction models for Arabica coffee beverage quality based on aroma analyses and chemometrics
AbstractIn this work, soft modeling based on chemometric analyses of coffee beverage sensory data and the chromatographic profiles of volatile roasted coffee compounds is proposed to predict the scores of acidity, bitterness, flavor, cleanliness, body, and overall quality of the coffee beverage. A partial least squares (PLS) regression method was used to construct the models. The ordered predictor selection (OPS) algorithm was applied to select the compounds for the regression model of each sensory attribute in order to take only significant chromatographic peaks into account.The prediction errors of these models, using 4 or 5 latent variables, were equal to 0.28, 0.33, 0.35, 0.33, 0.34 and 0.41, for each of the attributes and compatible with the errors of the mean scores of the experts. Thus, the results proved the feasibility of using a similar methodology in on-line or routine applications to predict the sensory quality of Brazilian Arabica coffee
Study of the kinematics of a high-course steering system
30th International Conference on Flexible Automation and Intelligent Manufacturing (FAIM2021)
15-18 June 2021, Athens, GreeceIn a context of mobility disruption, due to the accelerated growth of new technologies and sustainability policies, a new class of vehicles is emerging, depending on the type and its function, requiring new technologies suited to its goal. The autonomous modular platforms emerged, in this scenario, to reduce the time of placing electric vehicles on the market, the complexity of the supply and the total cost of production of the vehicle. To facilitate and adapt maneuverability of vehicles to the future challenges of mobility, this paper presents the study of different solutions for a steering system integrated in a modular platform already existing, that enables the vehicles 360° and 90° movements. The difficulty of developing this project is to find a mechanism that meets all kinematic requirements, without compromising the other systems of control and stability of the movement. Thus, considering the parameters of traction and suspension, possible solutions are developed, subsequently tested with the use of the SolidWorks software. Finally, it is concluded that of the solutions tested, the most satisfactory is the one that presents the best kinematic characteristics allied to the smallest course, despite being one of the solutions with more components.info:eu-repo/semantics/publishedVersio
Nutritional composition and bioactivity of Umbilicus rupestris (Salisb.)Dandy: An underexploited edible wild plant
The inclusion of edible wild plants in human diet has been receiving an increasing attention, as they represent an
easily accessible source of nutrients, vitamins and antioxidants. In this work, the leaves of Umbelicus rupestris
(Salisb.) Dandy, an edible species for which only scarce data is available in literature, were thoroughly evaluated
for its nutritional profile, chemical characterization and bioactive properties. Being considered a succulent plant,
the leaves revealed a very high content of moisture, with several beneficial compounds, including omega-3
polyunsaturated fatty acids, tocopherols and different polyphenols. A total of twelve flavonoids, three phenolic
acids and one phenylpropanoid glucoside were identified in the decoction and/or hydroethanolic extracts, with
most of them being described for the first time in this plant. Both extracts showed antioxidant activity and
potential to inhibit some of the assayed bacteria, while not presenting cytotoxic effects on a non-tumour primary
cell culture.The authors are grateful to the Foundation for Science and
Technology FCT, Portugal) and FEDER under Programme PT2020 for
financial support to CIMO (UID/AGR/00690/2019). L. Barros, R.C.
Calhelha, and A. Fernandes thank national funding by FCT, P.I.,
through the institutional scientific employment program-contract. For
their contracts. This work was also funded by FEDER-Interreg España-
Portugal programme through the project 0377_Iberphenol_6_E.info:eu-repo/semantics/publishedVersio
Epidemiological status of bovine brucellosis in the Federal District, Brazil
Realizou-se um estudo para caracterizar a situação epidemiológica da brucelose bovina no Distrito Federal (DF). No total foram amostrados 2.019 animais, provenientes de 278 propriedades. Em cada propriedade visitada aplicou-se um questionário epidemiológico para verificar o tipo de exploração e as práticas de criação e sanitárias que poderiam estar associadas ao risco de infecção pela doença. O protocolo utilizado foi o da triagem com o teste do antÃgeno acidificado tamponado e a confirmação dos positivos com o teste do 2-mercaptoetanol. O rebanho foi considerado positivo quando pelo menos um animal foi reagente à s duas provas sorológicas. A prevalência no DF foi de 2,5% [1,0-5,1%] para propriedades e de 0,16% [0,04-0,28%] para animais. Em razão dos resultados encontrados, que permitem pensar em estratégias de erradicação, recomenda-se que o DF intensifique o diagnóstico de brucelose, tanto na forma de testes sorológicos sistemáticos como pela introdução de mecanismos de detecção rápida em laticÃnios, em ambos os casos a fim de aumentar o número de propriedades certificadas como livres da doença e melhorar a sensibilidade do sistema de vigilância ativa.A study to characterize the epidemiological status of brucellosis was carried out in the Federal District of Brazil. A total of 2,019 serum samples from 278 herds were collected. In each herd, it was applied an epidemiological questionnaire focused on herd traits as well as husbandry and sanitary practices that could be associated with the risk of infection. The serum samples were screened for antibodies against Brucella spp. by the Rose-Bengal Test (RBT), and all positive sera were re-tested by the 2-mercaptoethanol test (2-ME). The herd was considered positive if at least one animal was positive on both RBT and 2-ME tests. Herd prevalence was estimated as 2.5% [1.0-5.1%] whereas animal prevalence was 0.16% [0.04-0.28%]. Given these results, that may warrant the implementation of eradication strategies, there is a case for intensifying the serological testing in the Federal District, coupled with the introduction of rapid detection methods by the dairy industries, with a view to increasing the number of accredited free herds and improving the sensitivity of the surveillance system..FAPESPCNPqSEAP-DFMAPA Ministério da Agricultura, Pecuária e Abasteciment
Analytical characterization of the aroma of Tinta Negra Mole red wine: Identification of the main odorants compounds
A method for the simultaneous determination of major and minor volatiles composition in different types (dry, medium dry, sweet and medium sweet) of a young Tinta Negra Mole (TNM) monovarietal red wine from 2003 harvest has been validated. Wine samples preparation includes a dichloromethane liquid–liquid extraction followed by concentration under a nitrogen atmosphere. The extracted fraction was analysed by gas chromatography–mass spectrometry and give quantitative information for more than 86 analytes whose concentration range from few μg l−1 to 259.1 mg l−1. The method enables high recovery of volatile compounds in wine good linearity with (r2) values higher than 0.980 and good sensitivity. The limits of detection range from 0.003 to 0.534 mg l−1 and limits of quantification from 0.009 to 1.170 mg l−1.
The method allows satisfactory determination of more than 80 compounds in the TNM red wines. These wines are characterized by a high content of higher alcohols, ethyl esters, fatty acids and lactones. The levels of sulphur compounds in Tinta Negra Mole medium sweet wines are very low, but they have the highest concentration of carbonyl compounds. Quantitative analysis of the main odorants followed by the determination of aroma index allow us elucidate the aroma of these varieties. On the basis of their odour description and odour threshold, the most powerful odorants of Tinta Negra Mole wines were tentatively established
Tuberculosis determined by Mycobacterium bovis in captive waterbucks (Kobus ellipsiprymnus) in São Paulo, Brazil
Two waterbucks from São Paulo Zoo Foundation exhibited respiratory symptoms in July 2004. After euthanasia, granulommas in lungs and mediastinic lymph nodes were observed. Acid-fast bacilli isolated were identified as Mycobacterium bovis spoligotype SB0121 by PRA and spoligotyping. They were born and kept in the same enclosure with the same group, without any contact to other species housed in the zoo. This is the first detailed description of M. bovis infection in Kobus ellipsiprymnus.FAPES
Ferromagnetism and Canted Spin Phase in AlAs/GaMnAs Single Quantum Wells: Monte Carlo Simulation
The magnetic order resulting from a confinement-adapted
Ruderman-Kittel-Kasuya-Yosida indirect exchange between magnetic moments in the
metallic phase of a AlAs/Ga(1-x)Mn(x)As quantum well is studied by Monte Carlo
simulation. This coupling mechanism involves magnetic moments and carriers
(holes), both coming from the same Mn(2+) ions. It leads to a paramagnetic, a
ferromagnetic, or a canted spin phase, depending on the carrier concentration,
and on the magnetic layer width. It is shown that high transition temperatures
may be obtained.Comment: 7 figure
Tailoring Ca3Co4O9 microstructure and performances using a transient liquid phase sintering additive
et al.A flexible, adaptable, economical and easily scalable processing route, allowing microstructural control, is presented. It involves classical solid state sintering method and addition of liquid promoting compound. Controlled porosity and high thermoelectric performance have been attained in CaCoO by KCO additions, drastically improving the sintering procedure. KCO behaves as transient liquid phase, providing microstructural benefits, vanishing during sintering. Electrical resistivity was improved by enhanced grains connectivity and growth. Significant increase in Seebeck coefficient at high temperatures has been produced while lattice thermal conductivity was unaffected. The best ZT value, estimated at 800°C, assuming the thermal conductivity value at 140°C, is 0.35 for 5wt.% KCO samples. These values are significantly higher than that obtained in highly-dense textured materials at the same temperature. The results suggest that this approach is very effective for preparing highly-performing CaCoO-based thermoelectric materials with relatively high porosity to control thermal conductivity.The authors wish to thank the MINECO-FEDER (MAT2013-46505-C3-1-R) and Gobierno de Aragón-Fondo Social Europeo (Research Groups T12 and T87) for financial support. This research was also partially supported by FCT, Portugal (IF/00302/2012 and PEst-C), project RECI/CTM-CER/0336/2012 co-financed by FEDER, QREN reference COMPETE: FCOMP-01-0124-FEDER-027465, and the projects financed by national funds through the FCT/MEC: UID/CTM/50025/2013, UID/CTM/50011/2013.Peer Reviewe
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