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Charneca A.,Instituto Superior Of Engineering Of Lisbon | Karmali A.,Instituto Superior Of Engineering Of Lisbon | Vieira M.,Polytechnic Institute of Lisbon
Sensors and Actuators, B: Chemical | Year: 2015

Abstract Glucose monitoring in vivo is a crucial issue for gaining new understanding of diabetes. Glucose binding protein (GBP) fused to two fluorescent indicator proteins (FLIP) was used in the present study such as FLIP-glu- 3.2 mM. Recombinant Escherichia coli whole-cells containing genetically encoded nanosensors as well as cell-free extracts were immobilized either on inner epidermis of onion bulb scale or on 96-well microtiter plates in the presence of glutaraldehyde. Glucose monitoring was carried out by Förster Resonance Energy Transfer (FRET) analysis due the cyano and yellow fluorescent proteins (ECFP and EYFP) immobilized in both these supports. The recovery of these immobilized FLIP nanosensors compared with the free whole-cells and cell-free extract was in the range of 50-90%. Moreover, the data revealed that these FLIP nanosensors can be immobilized in such solid supports with retention of their biological activity. Glucose assay was devised by FRET analysis by using these nanosensors in real samples which detected glucose in the linear range of 0-24 mM with a limit of detection of 0.11 mM glucose. On the other hand, storage and operational stability studies revealed that they are very stable and can be re-used several times (i.e. at least 20 times) without any significant loss of FRET signal. To author's knowledge, this is the first report on the use of such immobilization supports for whole-cells and cell-free extract containing FLIP nanosensor for glucose assay. On the other hand, this is a novel and cheap high throughput method for glucose assay. © 2015 Elsevier B.V.


Fernandes J.P.,Instituto Superior Of Engineering Of Lisbon | Lopes E.M.D.,Instituto da Soldadura e Qualidade | Maneta V.,Alstom
Journal of Engineering for Gas Turbines and Power | Year: 2010

Demand for power is growing everyday, mainly due to emerging economies in countries such as China, Russia, India, and Brazil. During the last 50 years steam pressure and temperature in power plants have been continuously raised to improve thermal efficiency. Recent efforts to improve efficiency leads to the development of a new generation of heat recovery steam generator, where the Benson once-through technology is applied to improve the thermal efficiency. The main purpose of this paper is to analyze the mechanical behavior of a high pressure superheater manifold by applying finite element modeling and a finite element analysis with the objective of analyzing stress propagation, leading to the study of damage mechanism, e.g., uniaxial fatigue, uniaxial creep for life prediction. The objective of this paper is also to analyze the mechanical properties of the new high temperature resistant materials in the market such as 2Cr Bainitic steels (T/P23 and T/P24) and also the 9-12Cr Martensitic steels (T/P91, T/P92, E911, and P/T122). For this study the design rules for construction of power boilers to define the geometry of the HPSH manifold were applied. © 2010 by ASME.


MacHado V.M.,Center for Innovation in Electric and Energy Engineering | Borges J.,Instituto Superior Of Engineering Of Lisbon | De Sousa J.,Instituto Superior Of Engineering Of Lisbon
Studies in Applied Electromagnetics and Mechanics | Year: 2010

This paper is a contribution to the magnetic field evaluation due to overhead power lines. The soil correction terms, based on Carson's solution, are included in their complete form and are evaluated resorting to numerical techniques. Results for the magnetic induction field are presented for a typical high voltage power transmission line. Comparisons are made with empirical data as well as with results obtained using other numerical methods. © 2010 The authors and IOS Press. All rights reserved.

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