A nondestructive diagnostic method based on swept-frequencyultrasound transmission-reflection measurements

A nondestructive diagnostic technique is proposed to measure depth and thickness of unwanted inclusions inside laminate-type materials (gaps, delaminations, and cracks, for example). The method is based on the frequency-domain analysis of transmission and reflection coefficient measured on the material under test when it is irradiated by a CW ultrasound beam whose frequency varies over a suitable frequency range. By measuring the frequency distance between two adjacent minima in the attenuation and reflection coefficients the thickness and depth of the inclusion can be obtained. A practical implementation of the technique is suggested, and the first experimental results obtained by a laboratory setup are reported     

A State of the Art of Antioxidant Properties of Curcuminoids in Neurodegenerative Diseases

Neurodegenerative diseases represent a set of pathologies characterized by an irreversible and progressive, and a loss of neuronal cells in specific areas of the brain. Oxidative phosphorylation is a source of energy production by which many cells, such as the neuronal cells, meet their energy needs. Dysregulations of oxidative phosphorylation induce oxidative stress, which plays a key role in the onset of neurodegenerative diseases such as Alzheimer’s disease (AD), Parkinson’s disease (PD), and amyotrophic lateral sclerosis (ALS). To date, for most neurodegenerative diseases, there are no resolute treatments, but only interventions capable of alleviating the symptoms or slowing the course of the disease. Therefore, effective neuroprotection strategies are needed. In recent years, natural products, such as curcuminoids, have been intensively explored and studied for their therapeutic potentials in several neurodegenerative diseases. Curcuminoids are, nutraceutical compouns, that owen several therapeutic properties such as anti-oxidant, anti-inflammatory and neuroprotective effects. In this context, the aim of this review was to provide an overview of preclinical and clinical evidence aimed to illustrate the antioxidant effects of curcuminoids in neurodegenerative diseases. Promising results from preclinical studies encourage the use of curcuminoids for neurodegeneration prevention and treatment.     

Analysis of the Electromagnetic Interaction Between a Resonator and a Lossy Dielectric Body as a First Theoretical Approach to Noninvasive Heart Movement Detection

In this paper the electromagnetic interaction between a resonator and a lossy dielectric body is examined by means of a simple model suitable for computer simulation; the body was assumed to have a revolution form and the resonator was electromagnetic coupled to the body by its inductive element constituted by a planar circular or spiral coil. On the basis of the model a computer program was derived which allows a simple numerical evaluation of the variation in the resonant frequency caused by the interaction mentioned above.     

A Procedure to Detect Flaws inside Large Sized Marble Blocks by Ultrasound

In the stone and marble industry there is considerable interest in the possibility of using ultrasound diagnostic techniques for non-destructive testing of large sized blocks in order to detect internal flaws such as faults, cracks, and fissures. In this paper we propose a specific diagnostic procedure for non-invasive, non-destructive quality control of marble blocks. Finally, the structure of a measuring set up specifically designed for in-field use is described and the experimental results are reported and discussed.     

A planar applicator for measuring surface dielectric constant ofmaterials

An applicator is described which allows the surface dielectric constant of a body to be measured simply by putting the device upon the body itself and by measuring the resulting capacitance value using a hand-held portable capacitance meter. The performances of the sensor were first verified by testing materials with known dielectric properties. Its particular use in measuring the dielectric constant of ceramic materials, plastic materials and of commonly used marbles and stones was then considered. Such application may be of interest in the case where the surface dielectric constant of marble and stone can be related to alterations of the external layer of these materials caused by atmospheric pollutants     

Microwave-assisted photochemical reactor for the online oxidative decomposition and determination of p-hydroxymercurybenzoate and its thiolic complexes by cold vapor generation atomic fluorescence detection

We developed a photochemical method for the online oxidation of p-hydroxymercurybenzoate (PHMB), an organic mercury species widely used for mercaptan and thiolic compound labeling. The method is based on a fully integrated online UV/microwave (MW) photochemical reactor for the digestion of PHMB, followed by cold vapor generation atomic fluorescence spectrometry (CVG-AFS) detection. The MW/UV process led to the quantitative conversion of PHMB and thiol-PHMB complexes to Hg(II), with a yield between 91% and 98%, without using chemical oxidizing reagents and avoiding the use of toxic carcinogenic compounds. This reaction was followed by the reduction of Hg(II) to Hg(0), performed in a knitted reaction coil with NaBH(4) solution, and AFS detection in an Ar/H(2) miniaturized flame. The low MW power applied (18 W) allowed us to keep constant the temperature of the photochemical reactor (21 ± 1 °C), using a flowing water bath. This avoided peak widening due to diffusion processes generally occurring at high temperatures and in the additional cooling coil. This method has been applied to the determination of thiols in human plasma, blood, and wine.     

Microstrip system for voltage-controlled phase equalisation for microwaves

A group-delay reflective-mode microwave equaliser is proposed. The required delay is obtained combining several voltagecontrolled circulator-coupled elementary cells. For an assigned phase response, the circuit is designed by an interactive program. Experimental results are reported relative to L band systems with constant and linear delay.     

High-throughput screening of protein surface activity via flow injection analysis-pH gradient-dynamic surface tension detection

Using flow injection analysis (FIA), a pH gradient is blended in real time with a protein sample as the pH-dependent protein surface activity is measured by a dynamic surface tension detector (FIA-pH-DSTD). This instrumental system was developed as a high-throughput method for the screening of protein surface activity at the air/liquid interface as a function of pH. This method utilizes the continuous flow, drop-based dynamic surface tension detector in combination with flow injection sample introduction and blending of a steady-state concentration of protein sample with a pH gradient ranging from pH 2.0 to pH 11.5. Dynamic surface tension is measured through the differential pressure across the air/liquid interface of repeatedly growing and detaching drops. Continuous surface tension measurement is achieved for each eluting drop of 2-s length (2 muL), providing insight into both the kinetic and thermodynamic behaviors of molecular orientation processes at the liquid/air interface. Three-dimensional data are obtained, with surface tension first converted to surface pressure, which is collected as a function of elution time versus drop time. In FIA-pH-DSTD, a commercial pH probe is used to measure pH during elution time, enabling surface pressure throughout drop time to be subsequently plotted as a function of eluting pH. An automated DSTD calibration procedure and data analysis method is applied, which allows simultaneous use of two different solvents, permitting real-time dynamic surface tension data to be obtained. The method was applied to the analysis of 14 commercial purified proteins, yielding characteristic features of surface activity as a function of pH. The reproducibility of the measurement and selectivity advantage of the DSTD was shown for the analysis of serum albumins from various mammalian sources. Several applications were also suggested and discussed in order to show the potential of the method for protein and food chemistry studies and in the study of protein-polymer interactions.     

Efficacy of Sulforaphane in Neurodegenerative Diseases

Sulforaphane (SFN) is a phytocompound belonging to the isothiocyanate family. Although it was also found in seeds and mature plants, SFN is mainly present in sprouts of many cruciferous vegetables, including cabbage, broccoli, cauliflower, and Brussels sprouts. SFN is produced by the conversion of glucoraphanin through the enzyme myrosinase, which leads to the formation of this isothiocyanate. SFN is especially characterized by antioxidant, anti-inflammatory, and anti-apoptotic properties, and for this reason, it aroused the interest of researchers. The aim of this review is to summarize the experimental studies present on Pubmed that report the efficacy of SFN in the treatment of neurodegenerative disease, including Alzheimer’s disease (AD), Parkinson’s disease (PD), and multiple sclerosis (MS). Therefore, thanks to its beneficial effects, SFN could be useful as a supplement to counteracting neurodegenerative diseases.     

An ultrasound-based simple noninvasive procedure for abrasive slurries efficiency control

Slurries are widely used in industry. Correct usage always requires granulometric measurements. Several methods are available, but the most attractive ones are on-line, noninvasive ultrasound based techniques. In this paper a simple procedure is proposed that refers to the use of abrasive slurries in sawing processes. The procedure uses ultrasound attenuation measurements to optimize the process efficiency by the on-line granulometric characterization of the abrasive slurry itself.