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Electromagnetic sensors can be exploited to determine properties (i.e., density) of hot mix asphalts (HMAs) by observing the surface polarization effects that occur in the radio frequency range of the electromagnetic spectrum. A challenge is the modeling of electromagnetic sensors, which do not require penetrating probes to perform the measurement. Moreover, core extraction is time consuming and subjected to technical and operator errors. In this paper, in order to model an electromagnetic sensor for HMA density measurement, a finite element code modeling a particular case of study has been exploited. A subsequent objective has been to determine HMA electrical characteristics and their relation with density values obtained with a nonnuclear device evaluating in-place HMA pavement. An experimental plan has been designed. The obtained results demonstrate that the implemented model is able to explain the relationship between density and electrical properties of HMA layers. Practical applications and recommendation have been outlined. DOI: 10.1061/(ASCE)MT.1943-5533.0000088 CE Database subject headings: Finite element method: Probe instruments: Material properties: Asphalts; Mixtures. Author keywords: FEM; Electromagnetic sensor; HMA; Material properties.

Nondestructive testing techniques are more and more exploited in order to quickly and cheaply recognize flaws into the inspected materials. Within this framework, a concern of eddy current tests is the depth of penetration [delta], above all in such applications as the control of steel beams. Thus, an optimal design of exciting coil is strictly required in order to reach as higher 6 as possible. The aim of this paper is first to design, by finite-element analysis, and test by in-lab measurements, a suitable exciting coil. Subsequently, the inverse ill-posed problem for defect characterization, starting from experimental measurements, has been studied and regularized, in order to characterize the depth and the extension of defects. Index Terms--Deep cylindrical defects, eddy current, fluxgate sensor, metallic plates.

Eddy current techniques for nondestructive testing and evaluation (NDT/NDE) of conducting materials is one of most application-oriented field of research within electromagnetics. In this paper, quantitative NDE of corrosion in metallic plates is considered. The inspection method exploits impedance measurements to determine the material loss profile caused by corrosion. Considering the corrosion shape as a function of impedance measurements, it has to be minimized in order to obtain the corrosion profile. In particular, swarm intelligence, characterized by evolutionary computation, has been exploited for the purpose. The proposed approach has been compared with results known in scientific literature both for performances and time consuming, with encouraging results. Index Terms--Corrosion profile reconstruction, eddy current, swarm intelligence.

Development of fast and accurate models of microwave devices and antennas is of paramount importance in computer-aided design and circuit analysis. At this purpose, artificial neural networks (ANNs) have been extensively exploited in technical literature. However, in the last years support vector machines (SVMs) developed by Vapnik are gaining popularity due to many attractive features capable to overcome the limitations connected to ANNs. In this work, support vector regression machines (SVRMs) modelling performances are investigated and compared with ANNs performances by means of several cases of study. Index Terms--Computer-aided design (CAD) modelling, microstrip patch antennas, microstrip radial stubs, support vector regression machines (SVRMs).

Colloidal systems consisting of monodomain superparamagnetic nanoparticles have been used in biomedical applications, such as the hyperthermia treatment for cancer. In this type of colloid, called a nanofluid, the nanoparticles tend to agglomeration. It has been shown experimentally that the nanoparticle coating plays an important role in the nanoparticle dispersion stability and biocompatibility. However, theoretical studies in this field are lacking. In addition, the ways in which the nanoparticle coating influences the magnetic properties of the nanoparticles are not yet understood. In order to fill in this gap, this study presents a numerical simulation model that elucidates how the nanoparticle coating affects the nanoparticle agglomeration tendency as well as the effective magnetic relaxation time of the system. To simulate the self-organization of the colloidal nanoparticles, a stochastic Langevin dynamics method was applied based on the effective Verlet-type algorithm. The Néel magnetic relaxation time was obtained via the Coffey method in an oblique magnetic field, adapted to the local magnetic field on a nanoparticle., (Copyright © 2020, Osaci and Cacciola; licensee Beilstein-Institut.)

Objectives: The nutraceutical approach to the management of metabolic syndrome (MetS) might be a promising strategy in the prevention of cardio-metabolic risk. Low-dose bergamot-derived polyphenolic fraction (BPF) has been proven effective in patients with MetS, as demonstrated by a concomitant improvement in lipemic and glycemic profiles. The present study was aimed to further explore, in a sample of subjects receiving second generation antipsychotics (SGAs), the effects on body weight and metabolic parameters of a low dose of BPF (500 mg/day) administered for 60 days. Methods: Twenty-eight outpatients treated with SGAs assumed BPF at single daily dose of 500 mg/day for 60 days. Body weight, BMI, fasting levels of glucose, total cholesterol, high density lipoprotein cholesterol, low density lipoprotein cholesterol and triglycerides were determined; moreover, Brief Psychiatric Rating Scale (BPRS) was administered. Results: Low-dose BPF administration did not change clinical and metabolic parameters, as well as clinical symptoms in the study sample. At the end of the trial, among completers ( n = 24) only nine patients (37.5%) reached an LDL reduction >0 but <50%. Conclusions: Our results demonstrate that patients treated with SGAs may need higher BPF doses for obtaining the positive effects on body weight and metabolic parameters previously found in the general population at lower doses.

Background: Nanoparticles can be used in biomedical applications, such as contrast agents for magnetic resonance imaging, in tumor therapy or against cardiovascular diseases. Single-domain nanoparticles dissipate heat through susceptibility losses in two modes: Néel relaxation and Brownian relaxation., Results: Since a consistent theory for the Néel relaxation time that is applicable to systems of interacting nanoparticles has not yet been developed, we adapted the Coffey theoretical model for the Néel relaxation time in external magnetic fields in order to consider local dipolar magnetic fields. Then, we obtained the effective relaxation time. The effective relaxation time is further used for obtaining values of specific loss power (SLP) through linear response theory (LRT). A comparative analysis between our model and the discrete orientation model, more often used in literature, and a comparison with experimental data from literature have been carried out, in order to choose the optimal magnetic parameters of a nanoparticle system., Conclusion: In this way, we can study effects of the nanoparticle concentration on SLP in an acceptable range of frequencies and amplitudes of external magnetic fields for biomedical applications, especially for tumor therapy by magnetic hyperthermia.

The systematic use of nondestructive testing assumes a remarkable importance where on-line manufacturing quality control is associated with the maintenance of complex equipment. For this reason, nondestructive testing and evaluation (NDT/NDE), together with accuracy and precision of measurements of the specimen, results as a strategic activity in many fields of industrial and civil interest. It is well known that nondestructive research methodologies are able to provide information on the state of a manufacturing process without compromising its integrity and functionality. Moreover, exploitation of algorithms with a low computational complexity for detecting the integrity of a specimen plays a crucial role in real-time work. In such a context, the production of carbon fiber resin epoxy (CFRP) is a complex process that is not free from defects and faults that could compromise the integrity of the manufactured specimen. Ultrasonic tests provide an effective contribution in identifying the presence of a defect. In this work, a fuzzy similarity approach is proposed with the goal of localizing and classifying defects in CFRP in terms of a sort of distance among signals (measure of ultrasonic echoes). A field-programmable gate array (FPGA)-based board will be also presented which implements the described algorithms on a hardware device. The good performance of the detection and classification achieved assures the comparability of the results with the results obtained using heuristic techniques with a higher computational load.

Purpose: Oxcarbazepine (OZC) is a second-generation antiepileptic drug (AED) that also may be used as a mood stabilizer. Unlike carbamazepine (CBZ), which is an inducer of the cytochrome P-450 isoforms and may accelerate the elimination of several therapeutic agents, OXC seems to have only a modest inducing action. The aim of this investigation was to evaluate the effect of a treatment with OXC on plasma concentrations of the new antipsychotics risperidone and olanzapine., Methods: OXC, at a dosage of 900-1,200 mg/day, was administered for 5 consecutive weeks to 25 outpatients, 10 men and 15 women, aged 25 to 64 years, with bipolar or schizoaffective disorder. Twelve patients were stabilized on risperidone therapy (2-6 mg/day) and 13 on olanzapine (5-20 mg/day). Steady-state plasma concentrations of risperidone and its active metabolite 9-hydroxyrisperidone (9-OH-risperidone) and olanzapine were measured by high-pressure liquid chromatography (HPLC) before addition of OXC and after 5 weeks from the start of adjunctive treatment., Results: OXC caused only minimal and no significant changes in the mean plasma levels of risperidone (from 5.6 +/- 3.6 ng/ml at baseline to 4.8 +/- 2.6 ng/ml at week 5), 9-OH-risperidone (from 23.6 +/- 7.5 to 24.7 +/- 7.4 ng/ml), and olanzapine (from 26.5 +/- 5.7 ng/ml at baseline to 27.8 +/- 5.1 ng/ml). OXC coadministration with either risperidone or olanzapine was well tolerated., Conclusions: Our findings indicate that OXC does not affect the elimination of risperidone and olanzapine, thus confirming its weak inducing effect on hepatic drug-metabolizing enzymes.