Point-of-care (PoC) diagnostics for bacterial detection offer tremendous prospects for public health care improvement. However, such tools require the complex combination of the following ...performances: rapidity, selectivity, sensitivity, miniaturization and affordability. To meet these specifications, this paper presents a new selectivity method involving lysostaphin together with a CMOS-compatible impedance sensor for genus-specific bacterial detection. The method enables the sample matrix to be directly flown on the polydopamine-covered sensor surface without any pre-treatment, and considerably reduces the background noise. Experimental proof-of-concept, explored by simulations and confirmed through a setup combining simultaneous optical and electrical real-time monitoring, illustrates the selective and capacitive detection of Staphylococcus epidermidis in synthetic urine also containing Enterococcus faecium. While providing capabilities for miniaturization and system integration thanks to CMOS compatibility, the sensors show a detection limit of ca. 10(8) (CFU/mL).min in a 1.5 μL microfluidic chamber with an additional setup time of 50 min. The potentials, advantages and limitations of the method are also discussed.
•Image processing methods for surface functionalization characterization were developed.•Functionalized sensors were characterized by confocal fluorescence microscopy.•Functionalization protocols ...were compared based on binding molecule efficiency.•Image processing allows a quantitative analysis of functionalization efficiency.•Homogeneity, coverage, stability, robustness and reproducibility were evaluated.
This work describes the development of a characterization method for biofunctionalized surfaces and its use for biosensor applications. The method is based on the processing of fluorescence images obtained by confocal microscopy. It retrieves quantitative data about the quantity and distribution of surface bound biomolecules, used to improve a biosensor performances in terms of specificity and sensitivity. Two biofunctionalization protocols were compared using the developed tools based on the fluorescence intensity, the surface coverage and the homogeneity of repartition of the fluorescence. In addition, the stability of the layer under flow, as well as the reproducibility and robustness of the protocols were evaluated.
Simulated annealing: a proof of convergence Granville, V.; Krivanek, M.; Rasson, J.-P.
IEEE transactions on pattern analysis and machine intelligence,
06/1994, Volume:
16, Issue:
6
Journal Article
Peer reviewed
We prove the convergence of the simulated annealing procedure when the decision to change the current configuration is blind of the cost of the new configuration. In case of filtering binary images, ...the proof easily generalizes to other procedures, including that of Metropolis. We show that a function Q associated with the algorithm must be chosen as large as possible to provide a fast rate of convergence. The worst case (Q constant) is associated with the "blind" algorithm. On the other hand, an appropriate Q taking sufficiently high values yields a better rate of convergence than that of Metropolis procedure.< >
Hemispherical photonic crystals found in species like Papilio blumei and Cicendella chinensis have inspired new applications like anti-counterfeiting devices and gas sensors. In this work, we ...investigate and compare four different ways to micro fabricate such hemispherical cavities: using colloids as template, by wet (HNA) or dry (XeF2) isotropic etching of silicon and by electrochemical etching of silicon. The shape and the roughness of the obtained cavities have been discussed and the pros/cons for each method are highlighted.
This article provides suggestions and ideas on the use of magnetic observatories to observe the stability of the gyromagnetic ratio of the proton and the electron in order to detect the effects of ...new fundamental physics and cosmology. The idea consist in long continuous recording of the signals Overhauser and optical pumping K magnetometers. Such systems can be highly effective network for forecasting earthquakes due to highest long term sensitivity.
Abstract
This report covers results of the long-term research directed at developing an absolute vector proton magnetometer based on the switching of bias magnetic fields. The distinctive feature is ...the attempt of the installation of a miniature Overhauser sensor and optimized Garret solenoid directly on the telescope of the theodolite. Thus this design (Declination Inclination Modulus Overhauser magnetometer: DIMOVER) will complement the universally recognised DIflux absolute device by adding full vector measurement capability. Preliminary designs, which also can be interesting to the experts in vector proton magnetometers, are presented.
In experiments, observations are often modelled as a noisy signal. If the signal is embedded in an additive Gaussian noise, its estimation is often done by finding a wavelet basis that concentrates ...the signal energy over few coefficients and by thresholding the noisy coefficients. However, in many problems of physics, the recorded data are not modelled by Gaussian noise but as the realisation of a Poisson process. In this case, a method of general Poisson process filtering is used. This widens the Gaussian noise filtering and is operated by a kind of frequency-and-
time hard thresholding of Haar wavelet coefficients. Not only the detail coefficients are thresholded but also the coefficients related to the rough approximation. Because of the distribution of the wavelet coefficients, a pair of thresholds is proposed for each coefficient. This filtering is illustrated with spectra from different experiments.
The knowledge transfer project called "Magnetic Valley" that was launched in 2009 is presented below. This project is funded by the Belgian government to investigate and develop products and services ...that will improve the socio-economic development in the area around the "Centre de Physique du Globe de l'IRM".
Abstract
We present the overall strategy used to upgrade 9 former USSR observatories to INTERMAGNET standards. The following aspects are discussed: application for funding to the INTAS European ...ad-hoc agency, choice of observatories to upgrade, choice of the instrumentation to purchase and to install, calibration of the instrumentation and used standards, back-ups, installation of the instrumentation and observatory real estate upgrade, acquisition and communication, training of the observers and documentation, evaluation of the upgrades and management of the project. Several observatories were successfully upgraded and we expect their INTERMAGNET certification soon.
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