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Mateusz Szymanski, Robert Porter
ELECTROCHEMICAL IMMUNOASSAY FOR CARDIAC MARKERS WITH MAGNETIC PARTICLES AS A SOLID PHASE AND SILVER NANOPARTICLES AS AN ELECTROACTIVE BIO-LABEL

This paper introduces a novel electrochemical detection method for measuring the formation of an immunological complex. The described electrochemical immunoassay consists of several consecutive steps. First the sample is mixed with silver colloid and magnetic particles both previously conjugated to appropriate antibodies. The analyte from the sample binds to both silver and magnetic beads forming a sandwich immunocomplex: magnetic particle – analyte – silver nanoparticle. That complex is separated from the sample with the use of magnetic field and then washed to remove any unbound silver nanoparticle. The bound silver nanoparticles are dissolved electrochemically into silver ions. This process is extensively investigated and the detailed mechanism of nanoparticles dissolution is presented. After the silver dissolution the released silver ions Ag+ are detected with anodic stripping voltammetry (ASV) and the ASV signal of silver oxidation is proportional to the analyte concentration. This approach allows for fast detection of cardiac markers like myoglobin and troponin in low volume, turbid samples with the detection limit of 200 and 150 pg/mL respectively.

Erik Molino Minero Re, Mariano López, Antoni Mànuel, Alfonso Carlosena, Xavier Roset
AN EVALUATION OF A SIMPLE DYNAMICAL MODEL FOR IMPACTS BETWEEN RIGID OBJECTS

The main purpose of this work is to propose a dynamical model for simulating the response of different metallic objects when impacted by another rigid body. In addition, a methodology for estimating the model parameters is presented and discussed. Results from real experiments shows that by assuming certain characteristics on impacting objects, the dynamic model can reproduce the transient dynamics during contact time.

Giovanni Battista Rossi, Birgitta Berglund
MEASUREMENT RELATED TO HUMAN PERCEPTION AND INTERPRETATION – STATE OF THE ART AND CHALLENGES

Measurement of characteristics related to human perception and interpretation is discussed. After a review of the historical framework current research activities are surveyed, on the basis of the authors' experience in European projects and coordination actions. Then future research needs and challenges are addressed.

Ludovít Kolláth, Martin Halaj, Eva Kureková
POSITIONING ACCURACY OF NON-CONVENTIONAL PRODUCTION MACHINES

The paper deals with machines employing parallel-kinematics structures (PKS). They represent a relatively new generation of machine tools. Depending on the number of struts, the machines are referred to as hexapod or tripod machines. Such machines offer several advantages comparing to the conventional machine tools with serial kinematics, such as high flexibility, high stiffness, and high accuracy. It is very suitable for High-Speed-Machining (HSM), light machining and has received a wide interesting in manufacture industry. To achieve a desired positioning accuracy and stability, the static and dynamic properties of the machine must be searched and mathematically described. The calculation of the estimate of positioning deviation, including respective uncertainty and covariances, is much more complicated task comparing to the serial kinematics.

Vaclav Papez, Jaroslav Roztocil, Stanislav Dado
SINE WAVE SIGNAL SOURCES FOR TESTING HIGH-SPEED HIGH-RESOLUTION A/D CONVERTERS

The paper deals with conception of a sine wave signal generation for dynamic testing high-speed (1 MSa/s to 100 MSa/s) analog-to-digital converters with high-resolution (14 to 20 bits). An oscillator designed with respect to minimal phase noise is described.

Cleonilson Protásio de Souza, Cláudio Leão Torres, Raimundo C. S. Freire, Francisco M. de Assis
ADC FUNCTIONAL TESTING USING ARTIFICIAL IMMUNE SYSTEMS

Artificial immune systems have been considered one of the most promising nature-inspired technique used for novelty detection systems, optimization, identification, etc. One of the main tools of these systems is the Negative-Selection Algorithm that is based on the natural self-nonself discrimination which has made possible the body distinguish any foreign cell from the body's self cell. In this work, it is used the Negative-Selection Algorithm to perform functional testing of analog-to-digital converter. In this way, the evaluation of the converter is performed by a set of immune-based detectors which can detect faulty output responses. Using the immune-based detector set, experimental results have been shown the effectiveness of the proposed method.

L. Zamora-Peredo, M. Hernández-Sustaita, Ivan C. Hernández, V. H. Méndez-García, M. López-López
PRELIMINARY EVALUATION OF QUANTUM HALL EFFECT DEVICES BY PHOTOREFLECTANCE SPECTROSCOPY

Internationally, an electrical resistance standard is based on quantum Hall effect devices and, usually, these are based in AlGaAs/GaAs heterostructures. In this work we report the study of a set of quantum Hall effect devices by photoreflectance spectroscopy at 300 K. An optical signal associated to the electric field build in the 2DEG region was found and it was used to identify the samples with superior electron mobility. With this study, is possible to offer an excellent nondestructive method before to make electrical contacts and magnetoresistance measurements.

Bruno Andò, Salvatore Baglio, Angela Beninato, Giorgio Fallica, Vincenzo Marletta, Nicola Pitrone
ANALYSIS AND DESIGN OF INDUCTIVE BIOSENSORS FOR MAGNETIC IMMUNO ASSAY

In this paper an inductive integrated sensor for biomedical applications is investigated through analytical models and numerical simulations such to obtain an optimized device design. This biosensor addressed here is based on the use of magnetic particles that suitably coated act as markers of the bio-molecule to be detected. The sensing principle of the device is related to the magnetic field thickening determined by the presence of magnetic particles in the active device area. An accurate finite element numerical simulation is therefore necessary to optimize the sensor performances; simulations have been performed by representing the magnetic particles with an equivalent volume having the same magnetic properties. The simulations have allowed analysing the influence of the different device parameters on the sensor response. An optimized design procedure has been therefore sketched and the results are reported in this paper.

Vladimir Vujicic, Ivan Župunski, Zoran Mitrovic, M. Sokola
MEASUREMENT IN A POINT VERSUS MEASUREMENT OVER AN INTERVAL

The paper reviews and discusses two strategies of digital measurements: measurement in a point and measurement over an interval. The first strategy, widely employed, has represented the backbone in measurement evolution and has become a standard method. For high accuracy measurements, it presents demanding requirements on technology regarding processing of measured signals. The second strategy, recently developed, carries clear advantages in three challenging areas of measurement theory and practice: measurement at high frequencies, measurement of noisy signals and measurements that require high linearity and high accuracy. These three advantages can be combined, as can be seen in the reviewed literature. This paper highlights the most important characteristics of the two measurement strategies.

Rüdiger Kessel, Raghu N. Kacker
CORRELATION IN UNCERTAINTY OF MEASUREMENT - A DISCUSSION OF STATE OF THE ART TECHNIQUES

The Guide to the expression of uncertainty has been around for 15 years and has been widely adopted by science and industry. Over time more and more complex measurements are evaluated based on these principles. As a consequence the correlation between quantities has become an important issue in the evaluation of measurement uncertainty. In this paper we will give an overview about covariance and correlation and the different state of the art techniques to handle them during the uncertainty evaluation. We will discuss the handling of observations by extending the well known calculus for the degrees of freedom for correlated cases. Next we will discuss the difficulties and limitations in handling correlations with Monte Carlo simulations together with a practical algorithm to ensure that correlation matrixes are positive semi-definite.

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