150 research outputs found

    Experimental assessment of the performance of two marine coatings to curb biofilm formation of microfoulers

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    Biofilms formed on submerged marine surfaces play a critical role in the fouling process, causing increased fuel consumption, corrosion, and high maintenance costs. Thus, marine biofouling is a major issue and motivates the development of antifouling coatings. In this study, the performance of two commercial marine coatings, a foul-release silicone-based paint (SilRef) and an epoxy resin (EpoRef), was evaluated regarding their abilities to prevent biofilm formation by Cyanobium sp. and Pseudoalteromonas tunicata (common microfoulers). Biofilms were developed under defined hydrodynamic conditions to simulate marine settings, and the number of biofilm cells, wet weight, and thickness were monitored for 7 weeks. The biofilm structure was analyzed by confocal laser scanning microscopy (CLSM) at the end-point. Results demonstrated that EpoRef surfaces were effective in inhibiting biofilm formation at initial stages (until day 28), while SilRef surfaces showed high efficacy in decreasing biofilm formation during maturation (from day 35 onwards). Wet weight and thickness analysis, as well as CLSM data, indicate that SilRef surfaces were less prone to biofilm formation than EpoRef surfaces. Furthermore, the efficacy of SilRef surfaces may be dependent on the fouling microorganism, while the performance of EpoRef was strongly influenced by a combined effect of surface and microorganism.This research was funded by Base Funding - UIDB/00511/2020 of the Laboratory for Process Engineering, Environment, Biotechnology, and Energy - LEPABE - funded by national funds through the FCT/MCTES (PIDDAC), “CVMAR+i - Industrial Innovation and Marine Biotechnology Valorization” project, funded by INTERREG V Espanha Portugal (POCTEP) (0302_CVMAR_I_1_P), and UIDB/04423/2020 and UIDP/04423/2020 (CIIMAR). The research work was also supported by UIDB/04046/2020 and UIDP/04046/2020 research units grants, Portugal (to BioISI). R.T.-S. thanks the receipt of a junior researcher fellowship from the Project PTDC/BII-BIO/29589/2017 POCI-01-0145-FEDER-029589 funded by FEDER funds through COMPETE2020 - Programa Operacional Competitividade e Internacionalização (POCI) and by national funds (PIDDAC) through FCT/MCTES. L.C.G. thanks the Portuguese Foundation for Science and Technology (FCT) for the financial support of her work contract through the Scientific Employment Stimulus-Individual Call-[CEECIND/01700/2017]. Atomic force microscopy technique was performed at the Biointerface and Nanotechnology i3S Scientific Platform with the assistance of Manuela Brás

    Avaliação do curso de Engenharia Florestal

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    O relatório resulta do trabalho de avaliação ao curso de Engenharia Florestal levado a cabo pela equipa de Auto-Avaliação da Escola Superior Agrária de Castelo Branco. Esta equipa, designada pelo conselho científico com a finalidade de proceder a todas as solicitações de avaliação tanto dos cursos como da instituição, é basicamente composta por um coordenador e um elemento de cada unidade departamental. Decorrente do tipo de curso que se está a avaliar juntam-se à equipa os respectivos coordenadores do curso e um relator. Além deste elementos participaram também neste trabalho um representante dos alunos (designado pela associação de estudantes) e dois funcionários representantes do pessoal administrativo e do pessoal não docente. Em termos metodológicos optou-se pelo seguimento do guião proposto pelo CNAVES, tendo-se recolhido informação de diversos modos: pesquisa documental e bases de dados nos serviços administrativos, inquéritos auto administrados a alunos, docentes e funcionários, inquérito postal aos diplomados e entrevistas directas às entidades empregadoras. Uma vez recolhida e tratada a informação procedeu-se à sua análise crítica tendo como referência os trabalhos de avaliação que até então decorreram relativamente à Escola e ao curso de Produção Florestal que antecedeu o actual curso de Engenharia Florestal

    Optimizing The Inspection Routine For The Detection Of Electrical Energy Theft In Aes Eletropaulo In São Paulo, Brazil

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    This work describes the development of a non-invasive and low-cost process that allows for the improvement of the energy theft inspection routine, increasing the field inspection team productivity and reducing the customer's embarrassment in cases where no irregularity is found. This new process is based on the development of an electronic Ah meter device that can be installed on the customer's pole input connections to the power lines. Using the recorded Ah value in the device, it is possible to estimate, within a margin of error, the energy consumption of the customer during a small period, typically one week. This energy value is compared to the customer's regular energy meter reading for the same period. A comprehensive statistical study performed with a database of more than 80000 customers in distribution area of the utility company AES Eletropaulo in São Paulo, Brazil concludes that the comparison between these readings can clearly indicate when tampered or defective meters are found.728089Depuru, S., Wang, L., Devabhaktuni, V., Gudi, N., Measures and setbacks for controlling electricity theft (2010) IEEE North American Power Symposium-NAPS(2009) Bureau for Economic Growth, Agriculture and Trade, , U. S. Agency for International Development Washington, D. C., Transforming Electricity Consumers into Customers: Case Study of a Slum Electrification and Loss Reduction Project in São Paulo, BrazilOnat, N., Transmission and distribution losses of Turkey's power system (2010) Proceedings of the 4th WSEAS Conference on Advances in Energy Planning, Environmental Education and Renewable Energy SourcesSmith, T., Electricity theft comparative analysis (2003) Energy Policy, 32, pp. 2067-2076Fitch, M., Graham, C., (2000) Electricity and Gas Theft, , Centre for Utility Consumer Law, University of Leicester, UKKenny, C., Soreide, T., (2008) Grand Corruption in Utilities, , World Bank Policy Research Working Paper 4805Sarpa, C., (2008) Electricity Theft and Non-payment: Impact on the sa Generation Capacity Crisis, , Yelland, Conference PaperOnat, N., Techno-economic analysis of illegal electricity usage in Turkey and policy proposals (2010) WSEAS Transactions on Power Systems, 3, pp. 213-222Stajic, Z., Janjic, A., Simendic, Z., Power quality and electrical energy losses as a key drivers for smart grid platform development (2011) Proceedings of the 15th WSEAS International Conference on Systems - Recent Researches in System Science, pp. 417-422Kadurek, P., Blom, J., Cobben, J., Kling, W., Theft detection and smart metering practices and expectations in the Netherlands (2010) Innovative Smart Grid Technologies Conference Europe (ISGT Europe) IEEE PESOliveira-De Jesus, P., Alvarez, M., De Ponce Leao, M., Yusta, J., A novel approach to evaluate incremental transmission losses (2009) WSEAS Transactions on Power Systems, 1, pp. 12-21Ghajar, R.F., Khalife, J., Cost/benefit analysis of an AMR system to reduce electricity theft and maximize revenues for Électricité du Liban (2003) Applied Energy, 76 (1-3), pp. 25-37. , DOI 10.1016/S0306-2619(03)00044-8Nagi, J., Mohammad, A., Yap, K., Tiong, S., Ahmed, S., Non-technical loss analysis for detection of electricity theft using support vector machines (2008) Proceedings of the 2nd IEEE International Conference on Power and Energy (PECon 08), pp. 907-912(2008) MSP430FE42x Mixed Signal Microcontroller Data-sheet, , Texas Instruments(2011) CC2550 Low-cost Low-power 2.4 GHz RF Transmitter Data-Sheet, , Texas InstrumentsMorais, F., (2011) Development of an Electronic Wireless RMS Current Meter for Applications in Detection of Electrical Energy Theft, , M. Sc. Thesis in Electrical Engineering, Faculty of Computer and Electrical Engineering, University of Campinas, BrazilPomilio, J., Deckmann, S., Characterization and compensation of harmonics and reactive power of residential and commercial loads (2007) IEEE Transactions on Power Delivery,

    Factors associated with false-negative cervical cytopathological results

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    Purpose: to evaluate whether factors related to the adequacy of the sample, cell pattern and cytomorphological criteria are associated with false-negative (FN) results of cervical cytopathology during routine examinations. Methods: this is a case-control study in which the study group included 100 cytopathologic smears with FN results detected during systematic internal quality control consisting of 100% rapid review. For each FN result detected, two smears with a true-positive diagnosis were identified by the same cytotechnician and these constituted the control group, making a total sample size of 300 smears. The variables were established in accordance with the criteria defined for the analysis of sample adequacy, cell pattern and cytomorphological analyzed criteria. The results were evaluated using bivariate analysis and logistic regression with stepwise variable selection criteria expressed in OR (95%). Results: the number of atypical cells, the appearance of nuclear chromatin, and the distribution and presentation of atypical cells in the smear were the variables that showed the greatest risk for FN results with OR of 9.6, 4.2, 4.4, and 3.6, respectively. Inflammatory processes and the presence of blood in the smear were also identified as variables that influence the risk of FN results. Conclusions: the majority of the factors associated with FN results are dependent on the conditions and techniques of sample collection, since in the majority of cases, the lesion may not be adequately represented in the smear. Confounding factors such as blood and inflammatory processes may also impair analysis. With respect to cytomorphological alterations, thin chromatin strand was the variable that indicated the greatest risk of FN results.Verificar se, no escrutínio de rotina, fatores relacionados com a adequabilidade da amostra, padrão celular e critérios citomorfológicos estão associados a resultados falso-negativos (FN) dos exames citopatológicos. Métodos: trata-se de um estudo caso-controle, no qual o grupo de casos incluiu 100 esfregaços citopatológicos com um resultado FN que foi detectado pela sistemática de controle interno da qualidade com revisão rápida de 100%. Para cada resultado FN detectado foram identifi cados,pelo mesmo citotécnico, dois esfregaços com um diagnóstico verdadeiro-positivo e este grupo foi considerado controle, totalizando uma casuística de 300 esfregaços. As variáveis analisadas foram estabelecidas de acordo com os critérios defi nidos para a análise da adequabilidade da amostra, padrão celular e critérios citomorfológicos. Os resultados foram avaliados por análise bivariada e regressão logística com critério de seleção de variáveis stepwise e expressos em OR (95%). Resultados: o número de células atípicas, aspecto da cromatina nuclear, distribuição e apresentação de células atípicas no esfregaço apresentaram risco maior para resultados FN, com OR de 9,6; 4,2; 4,4 e 3,6, respectivamente. Processo infl amatório e presença de sangue no esfregaço mostraram também risco para os resultados FN. Conclusões: a maioria dos fatores associados à liberação de um resultadoFN é dependente das condições e técnicas de coleta de material, pois, em grande parte, a lesão pode não estar adequadamente representada no esfregaço, e também fatores obscurecedores como sangue e processo infl amatório podem prejudicar a análise. Quanto às alterações citomorfológicas, cromatina fi na foi a característica que apresentou maior risco para resultados FN288479485To evaluate whether factors related to the adequacy of the sample, cell pattern and cytomorphological criteria are associated with false-negative (FN) results of cervical cytopathology during routine examinations. Methods: this is a case-control study in which the study group included 100 cytopathologic smears with FN results detected during systematic internal quality control consisting of 100% rapid review. For each FN result detected, two smears with a true-positive diagnosis were identified by the same cytotechnician and these constituted the control group, making a total sample size of 300 smears. The variables were established in accordance with the criteria defined for the analysis of sample adequacy, cell pattern and cytomorphological analyzed criteria. The results were evaluated using bivariate analysis and logistic regression with stepwise variable selection criteria expressed in OR (95%). Results: the number of atypical cells, the appearance of nuclear chromatin, and the distribution and presentation of atypical cells in the smear were the variables that showed the greatest risk for FN results with OR of 9.6, 4.2, 4.4, and 3.6, respectively. Inflammatory processes and the presence of blood in the smear were also identified as variables that influence the risk of FN results. Conclusions: the majority of the factors associated with FN results are dependent on the conditions and techniques of sample collection, since in the majority of cases, the lesion may not be adequately represented in the smear. Confounding factors such as blood and inflammatory processes may also impair analysis. With respect to cytomorphological alterations, thin chromatin strand was the variable that indicated the greatest risk of FN result

    Avaliação do curso de Engenharia de das Ciências Agrárias - Opção Engenharia Rural

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    O presente relatório resulta do trabalho de avaliação ao curso de Engenharia das Ciências Agrárias opção Engenharia Rural levado a cabo pela equipa de Auto-Avaliação da Escola Superior Agrária. Esta equipa, designada pelo conselho científico com a finalidade de proceder a todas as solicitações de avaliação tanto dos cursos como da instituição, é basicamente composta por um coordenador e um elemento de cada unidade departamental. Conforme o curso que se está a avaliar juntam-se à equipa o respectivo coordenador de curso e colaboradores na compilação do relatório. Além destes elementos participaram também neste trabalho um representante dos alunos (designado pela associação de estudantes) e dois funcionários representantes do pessoal administrativo e do pessoal não docente. Em termos metodológicos optou-se pelo seguimento mais ou menos fiel do guião proposto pelo CNAVES, tendo-se recolhido informação de diversos modos: pesquisa documental e bases de dados nos serviços administrativos, inquéritos auto administrados a alunos, docentes e funcionários, inquérito postal aos diplomados e entrevistas directas (por telefone) às entidades empregadoras. Uma vez recolhida e tratada a informação procedeu-se à sua análise crítica tendo como referência os trabalhos de avaliação que até então decorreram relativamente na Escola

    Angiotensin-converting enzyme inhibitor protects against cisplatin nephrotoxicity by modulating kinin B1 receptor expression and aminopeptidase P activity in mice

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    Cisplatin is a highly effective chemotherapeutic agent. However, its use is limited by nephrotoxicity. Enalapril is an angiotensin I-converting enzyme inhibitor used for the treatment of hypertension, mainly through the reduction of angiotensin II formation, but also through the increase of kinins half-life. Kinin B1 receptor is associated with inflammation and migration of immune cells into the injured tissue. We have previously shown that the deletion or blockage of kinin B1 and B2 receptors can attenuate cisplatin nephrotoxicity. In this study, we tested enalapril treatment as a tool to prevent cisplatin nephrotoxicity. Male C57Bl/6 mice were divided into 3 groups: control group; cisplatin (20 mg/kg i.p) group; and enalapril (1.5 mg;kg i.p) + cisplatin group. The animals were treated with a single dose of cisplatin and euthanized after 96 h. Enalapril was able to attenuate cisplatin-induced increase in creatinine and urea, and to reduce tubular injury and upregulation of apoptosis-related genes, as well as inflammatory cytokines in circulation and kidney. The upregulation of B1 receptor was blocked in enalapril + cisplatin group. Carboxypeptidase M expression, which generates B1 receptor agonists, is blunted by cisplatin + enalapril treatment. The activity of aminopeptidase P, a secondary key enzyme able to degrade kinins, is restored by enalapril treatment. These findings were confirmed in mouse renal epithelial tubular cells, in which enalaprilat (5 μM) was capable of decreasing tubular injury and inflammatory markers. We treated mouse renal epithelial tubular cells with cisplatin (100 μM), cisplatin+enalaprilat and cisplatin+enalaprilat+apstatin (10 μM). The results showed that cisplatin alone decreases cell viability, cisplatin plus enalaprilat is able to restore cell viability, and cisplatin plus enalaprilat and apstatin decreases cell viability. In the present study, we demonstrated that enalapril prevents cisplatin nephrotoxicity mainly by preventing the upregulation of B1 receptor and carboxypeptidase M and the increased concentrations of kinin peptides through aminopeptidase activity restoration
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