Centro Federal Of Educacao Tecnologica Celso Suckow Da Fonseca Cefet Rj

Brazil

Centro Federal Of Educacao Tecnologica Celso Suckow Da Fonseca Cefet Rj

Brazil

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Khan S.,Pontifical Catholic University of Rio de Janeiro | Khan S.,University of Swabi | Miguel E.M.,Pontifical Catholic University of Rio de Janeiro | de Souza C.F.,Pontifical Catholic University of Rio de Janeiro | And 2 more authors.
Sensors and Actuators, B: Chemical | Year: 2017

Kanamycin is an antibiotic from the aminoglycoside class used to treat a myriad of infections. Aminoglycosides enhanced the photoluminescence of the thioglycolic acid modified CdTe quantum dots (TGA-CdTe QDs) following a Langmuir binding isotherm model. Binding constants were calculated indicating strong interactions between surface of nanoparticles and aminoglycosides. For kanamycin, the equilibrium binding constant was of 5.6 × 107 L mol−1. Based on this, a sensitive and selective method was developed for kanamycin determination based on the enhanced photoluminescence of TGA-CdTe QDs. Solid phase extraction with a new molecularly imprinted polymer, made using kanamycin as a template, provided high selectivity towards aminoglycosides. Under adjusted conditions, the two orders of magnitude analytical curve (linearized Langmuir binding isotherm) was constructed from 1.4 × 10−8 mol L−1 (limit of quantification) to 1.6 × 10−6 mol L−1 (8.1–92.8 ng mL−1) of kanamycin sulphate. The proposed procedure was tested for the determination of kanamycin in milk and yellow fever vaccine with recoveries between 86.6 and 93.7%. In addition, the kanamycin effect on TGA-CdTe QDs was also demonstrated under capillary electrophoresis regime, indicating another possibility for selective sensing. © 2017 Elsevier B.V.


Santos C.O.,Centro Federal Of Educacao Tecnologica Celso Suckow Da Fonseca Cefet Rj | Scalon J.D.,Federal University of Lavras | Ozaki V.A.,University of Sao Paulo
Revista de Economia e Sociologia Rural | Year: 2014

The crop insurance sold in Brazil is estimated using the average of the municipal agricultural productivity of the last four or five years. Many researchers believe that using a probabilistic model for the distribution of agricultural productivity is a better methodology for this purpose. This study advocates using the skew-normal distribution as an alternative to the normal distribution to model the distribution of agricultural productivity in Brazil. We analyzed series of corn yield from 1981 to 2007, in 30 counties in Paraná State, Brazil. The skew-normal distribution showed better fits than the normal distribution for the vast majority of the counties, and, consequently, led to better estimates for the expected payment of crop insurance.


da Rocha Henriques F.,Centro Federal Of Educacao Tecnologica Celso Suckow Da Fonseca Cefet Rj | Lovisolo L.,State University of Rio de Janeiro | Rubinstein M.G.,State University of Rio de Janeiro
Eurasip Journal on Wireless Communications and Networking | Year: 2016

When a wireless sensor network (WSN) is employed to monitor environmental data, efficient energy usage is demanded so that the WSN lifetime can be extended. In this context, we propose a distributed energy conservation algorithm (DECA). DECA considers the known past to make predictions on the measurement change over time in order to put sensor nodes into sleep mode, saving energy. Sensor nodes compute their inactivity periods taking into account the inactivity periods of their neighboring nodes. The signals are reconstructed at the sink node, from the sampled values received from sensor nodes. DECA is designed to keep the reconstruction error of the monitored process below a given fraction of its actual value. Since DECA works on the application layer, it can be combined with medium access control and routing protocols to further improve energy management. The proposed algorithm is evaluated with simulations using real data. Results show gains in the network lifetime of up to 1000 % as compared to a WSN without any energy management, while maintaining the error of the reconstructed process at the sink within the desired fraction imposed. Since a strategy for managing the sleeping period in routing nodes is proposed, a metric for evaluating the effects of sleeping periods on network connectivity is also proposed. We have verified that the network connectivity is not impaired by the proposed algorithm, as packet delivery ratios above 90 % were obtained. © 2016, da Rocha Henriques et al.


PubMed | University of Wisconsin - Platteville, Laboratorio Of Biodiversidade Entomologica, Instituto Oswaldo Cruz, Federal University of Paraiba and Centro Federal Of Educacao Tecnologica Celso Suckow Da Fonseca Cefet Rj
Type: Journal Article | Journal: Journal of vector ecology : journal of the Society for Vector Ecology | Year: 2016

We conducted a lab-based comparative study on vector capacity features of two species of triatomines: Triatoma brasiliensis and T. melanica. Both are members of the T. brasiliensis species complex. The former is the most important Chagas disease vector in the northeastern region of Brazil. To date, no transmission via T. melanica has been recorded. Immature insects exhibited distinct intermoult periods without a direct relationship to a given species. Females of T. brasiliensis consumed an average of 1.9 times more meals (mean = 12.92 vs 6.63) and survived for a shorter period (mean =330.8 days) than T. melanica (mean = 365.2 days), probably due to the cost of reproduction (all significant at P<0.05). These data support the idea that T. brasiliensis is more adapted to lab conditions and is more able to infest domiciles than T. melanica. We also found significant distinctions in other features between these species, such as the elapsed time without eating before molting, which was higher for the second, third, and fifth nymph stages of T. melanica. Regarding features analyzed related to vector capacity, insects of all life stages of both species were considered competent to transmit Trypanosoma cruzi because they needed many feedings (mean =1.5-3.82) to moult and because a high proportion (>39%) of insects defecated rapidly (<30 s) after feeding. Overall, results highlight the need to extend vector surveillance to T. melanica.


PubMed | Centro Federal Of Educacao Tecnologica Celso Suckow Da Fonseca Cefet Rj and Pontifical Catholic University of Rio de Janeiro
Type: | Journal: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy | Year: 2016

Flavonoids are polyphenols that help the maintenance of health, aiding the prevention of diseases. In this work, CdTe QDs coated with 3-mercaptopropionic acid (3MPA), with an average size of 2.7nm, were used as photoluminescence probe for flavonoids in different conditions. The interaction between 14 flavonoids and QDs was evaluated in aqueous dispersions in the absence and in the presence of cetyltrimethylammonium bromide (CTAB). To establish a relationship between photoluminescence quenching and the concentration of flavonoids, the Stern-Volmer model was used. In the absence of CTAB, the linear ranges for quercetin, morin and rutin were from 5.010


PubMed | Centro Federal Of Educacao Tecnologica Celso Suckow Da Fonseca Cefet Rj and Pontifical Catholic University of Rio de Janeiro
Type: | Journal: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy | Year: 2016

Gentamicin is an antibiotic indicated to treat mastitis in dairy cattle and for the treatment of bacterial resistance in the context of hospital infections. The effect caused by gentamicin on the optical properties of gold nanoparticles aqueous dispersions were used to develop quantitative methods to determine this antibiotic. Two different aqueous dispersions, one containing spherical Au nanoparticles (AuNPs) and the other containing Au nanorods (AuNRs), had their conditions adjusted to enable a stable and sensitive response towards gentamicin. The use of AuNPs, with measurement at 681nm of the rising coupling plasmon band, enabled a limit of detection (LOD) of 0.4ngmL


de Almeida Guimaraes V.,Federal University of Fluminense | de Almeida Guimaraes V.,Centro Federal Of Educacao Tecnologica Celso Suckow Da Fonseca Cefet Rj | Leal Junior I.C.,Federal University of Fluminense
Journal of Cleaner Production | Year: 2016

Performance assessment of urban passenger transport is relevant since it causes economic, environmental and social impacts. Thus, this paper proposes a structured method to assess and evaluate the performance of passenger transport systems. Assuming that an eco-efficiency analysis is a step toward sustainability, we applied the method in a Brazilian case considering eco-efficiency measures, to show its potential as a tool to support decisions. We concluded that neither the most used alternative nor the one with the highest capacity attained the best eco-efficient performance, which can be explained by the low occupancy rates. Focusing on the latter, we propose some actions - based on the Brazilian and international literature - that can be implemented to improve its performance. © 2016 Elsevier Ltd.


Monteiro A.F.,Federal University of Fluminense | Monteiro A.F.,Centro Federal Of Educacao Tecnologica Celso Suckow Da Fonseca Cefet Rj | Loques O.,Federal University of Fluminense
Proceedings - Symposium on Computer Architecture and High Performance Computing | Year: 2016

This work presents a model for managing Virtual Application Servers (VAS) on cluster-based web servers. In addition to providing energy savings, our model has linear scalability and defines a default processing virtual web server, known as Quantum Virtual Machine (QVM). A set of QVM performs a Logical Web Server (LWS), which operates in a flexible manner, changing its performance and power consumption depending on the workload of the applications. Concepts of agile VAS clone, co-allocation of VAS in the same core, and Dynamic Voltage and Frequency Scaling (DVFS) are used in the model, enabling rapid configuration actions and a fine-grained QoS control. The experiments evaluate the effectiveness of the proposed model by means of power consumption reduction and QoS violation as compared to the Linux CPU governors and state-of-the-art approaches based on optimization. The results show our model conserves up to 51.8% of the energy required by a cluster designed for peak workload scenario, with a negligible impact on the applications performance. © 2015 IEEE.


The creation of the Brazilian Network of Comprehensive Occupational Health Care (Renast) in 2002 led to the appearance and increase of Reference Centers for Occupational Health (Cerest) in Brazil. In the North Fluminense Region, Cerest was inaugurated in 2006 and resulted from the transformation of the former Occupational Health Program of the city of Campos dos Goytacazes. In the broader context of the history of Occupational Health Programs in Brazil and the creation of Renast, this research analyzes the setting up of this Cerest in Campos in the State of Rio de Janeiro. In line with Foucault, it examines the specificity of its relations of provenance and emergence, conducting a review of the trajectory of the Occupational Health Program in the city in question. Documentary analysis, participant observation and interviews with Cerest team members were used as research tools. The survey revealed some political and social trouble spots. The results show that Cerest has a history of isolation and marginalization in the region's political and institutional structure. It acts continuously with a predominant logic of care since its inception, but it has faced serious political obstacles over the course of time in the implementation of actions to promote occupational health.


Monteiro A.F.,Federal University of Fluminense | Monteiro A.F.,Centro Federal Of Educacao Tecnologica Celso Suckow Da Fonseca Cefet Rj | Loques O.,Federal University of Fluminense
2014 IEEE International Conference on Cluster Computing, CLUSTER 2014 | Year: 2014

This paper presents the Quantum Mapper (QMapper), a model for managing Virtual Application Servers (VAS) on cluster-based web servers. In addition to providing energy savings and maintenance of the QoS of the cluster applications, the QMapper has linear scalability and defines a small-capacity processing virtual web server, known as Quantum VAS (QVAS). A QVAS operates in a flexible manner, changing its performance and power consumption depending on the workload. The results show that our model conserves up to 39% of the energy required by a cluster designed for peak workload scenario, with a negligible impact on the applications performance. © 2014 IEEE.

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