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Cardiac contractility modulation (CCM) is a novel device-based therapy used in patients with HFrEF. CCM therapy is associated with an improvement in exercise tolerance, increased quality of life, reduced HF hospitalizations, and reverse remodelling of the left ventricle in patients with HFrEF. In this case, we report the clinical benefit of CCM in an older patient with advanced HFrEF due to ischemic dilated cardiomyopathy with frequent heart failure-related hospitalizations and poor quality of life despite optimal medical therapy.

Introduction: The central nervous system is the generator of the dynamic balance between cholinergic and noradrenergic activity. Different behavioral tendencies are observed in subjects with prevalent parasympatic tone (defense strategy, energy sparing, dissociation) compared to those with sympathic one (relational interaction, high energy expenditure). These responses may influence susceptibility and vulnerability to diseases. The aim of our study was to examine cardiovascular function from the heart to the periphery by 24 hours detection of both heart and pulse rate in cerebrovascular conditions. Materials and Methods: We recruited 113 Acute Ischaemic Syndromes (AIS, age 73,43 sd 12,34), 32 Chronic Cerebro-Vascular Diseases (CCVD, age 75,95 sd 8,06), 30 Other Neurological Diseases (OND, age 50,09 sd 15,05). Cardiovascular reactivity (CR) was defined by beat indices, ratio (R) or difference (D) between higher maximal or minimal heart rate (HR) on higher maximal or minimal pulse rate (PR). A value < 1 or > 1 were considered as negative (NCR) or positive CR (PCR), respectively. Results: Max PR was significantly higher in CCVD and AIS compared to OND. Max CR was lower in CCVD and AIS compared to OND. Increased levels of glycosylated hemoglobin, cardiac biomarkers, abnormal findings at Holter ECG and Echocardiography were particularly observed in case of NCR. Conclusions: NCR may interfere with normal activity of daily living. Higher Hachinski ischaemic scores in these patients point out a higher ischaemic load. Moreover, NCR identified a category of acute patients with worst outcomes, requiring prompt intensive care because of higher risk of complications and mortality. Our observations may be useful for better choosing among therapeutical options, planning rehabilitation and health enhancing physical activity in aging. Moreover, they may reduce the risk of injuries for training overload in athletes.

Quality control is of great importance in food industry, both for the evaluation of product characteristics and to avoid the occurrence of foreign bodies contamination in packaged items. With respect to the inspections against possible contaminants inside the product, different technologies are currently adopted along production chain lines. However, the number of accidents involving low density objects remains very large. To overcome this limitation, the use of electromagnetic technologies has been recently proposed. In this work, the synergic use of terahertz and microwaves technologies is proposed, so to provide high resolution images and in-depth inspections of different scenarios, including low density materials. A focus study on sugar samples is considered, reporting both its broadband characterization at microwaves and preliminary terahertz imaging to evaluate the integrity of the packaging. Ongoing research is devoted to the development and validation of a microwave device for monitoring food products along the production line.

Magnetic nanoparticles-aided microwave imaging is an emerging modality for the diagnosis of early stage tumors. It exploits the possibility of modulating the response at microwaves of magnetic nanoparticles, employed as contrast agent selectively accumulated into the tumor. In this paper, we describe the results of an experimental study aimed at establishing the actual detection limits of the approach, namely the minimum amount of magnetic nanoparticles to be delivered for a reliable imaging. The assessment is carried out on breast phantoms made of ex-vivo minced pig tissues and using commercially available magnetic nanoparticles. The results show that it is possible to detect amounts of magnetic nanoparticles between 2 and 7 mg, dispersed in a volume of about one cubic centimeter, depending on the breast type. While such quantities are already consistent with those currently reachable via active selective targeting, an in-depth analysis of the results allows to identify strategies to further lower the detection limits up to four times, by refining the measurement set-up and setting the amplitude of the polarizing magnetic field modulating the nanoparticle response to a suitable value.

International audience; This work focuses on brain stroke imaging via microwave technology. In particular, the open issue of monitoring patients after stroke onset is addressed here in order to provide clinicians with a tool to control the effectiveness of administered therapies during the follow-up period. In this paper, a novel prototype is presented and characterized. The device is based on a low-complexity architecture which makes use of a minimum number of properly positioned and designed antennas placed on a helmet. It exploits a differential imaging approach and provides 3D images of the stroke. Preliminary experiments involving a 3D phantom filled with brain tissue-mimicking liquid confirm the potential of the technology in imaging a spherical target mimicking a stroke of a radius equal to 1.25 cm.

Brain stroke is one of the most common diseases worldwide. Magnetic resonance imaging and computerized tomography are currently the two most assessed and reliable diagnostic tools, of great support to the clinicians. However, these devices are costly, time consuming and not portable, so that they are not appropriate for bedside monitoring. Hence, there is an increasing worldwide interest to develop complementary techniques to continuously monitor a patient after the stroke onset. In this paper, we report about the experimental testing of a novel device able to monitor cerebrovascular diseases, whose realization is based on microwave imaging technology. A 2-D version of the device has been fully experimentally tested and its 3-D version is under development.

Magnetic nanoparticles (MNP) enhanced microwave imaging could provide an effective approach for an early stage diagnosis of breast cancer, if encouraging results coming from accurate and realistic numerical studies are confirmed by an experimental proof of concept framework. To this end, an ad hoc laboratory setup has been designed and built up to verify the possibility of detecting the low signal scattered by MNP when embedded into a simplified but realistic breast phantom. This paper describes the developed measurement setup and the results coming from a first run of experiments, which confirm the possibility to detecting realistic amounts of accumulated nanoparticles. Moreover, the experimental results analysis allows addressing the future developments required to determine the ultimate detection limits of the technique, giving relevant information to plan the preclinical assessment.

This paper deals with the optimal synthesis of sum or difference patterns radiated by an array of fixed geometry. The aim is to establish the most general class of arrays for which such synthesis can be reduced to a linear programming problem, extending and completing previous results regarding uniformly spaced (linear and planar) arrays. It is shown that such a class consists of the centrosymmetric arrays, whose element patterns are either equal or Hermitian symmetric with respect to the center of symmetry. The optimal solutions are also Hermitian symmetric and the corresponding patterns are real. Furthermore, it is shown that the above class of arrays coincides with that of the arrays capable of radiating real patterns. Some numerical examples are provided to give an idea of the geometries and the synthesis problems to which the achieved result successfully applies and of the achievable computational advantage.

This paper presents the design of a novel low-complexity microwave imaging system for monitoring brain stroke. In particular, the design is concerned with the determination of the optimal layout of the antennas array, namely, minimum number, positions, and polarization of the radiating elements, enabling the acquisition of an amount of data such to assure a reliable imaging. This goal is achieved by adopting a rigorous design procedure based on the inspection of the singular value decomposition of the relevant discretized scattering operator and taking into account the actual dynamics and signal-to-noise ratio of the measurement system. The design is first carried out in the case of ideal dipoles and then extended and assessed for actual printed monopole antennas, developed for the imaging system. The resulting system is a helmet equipped with 24 antennas, whose performances have been numerically validated in terms of both spatial resolution and reconstruction capabilities, by employing full-wave numerical simulations, realistic 3-D phantoms of the human head, and an accurate modeling of the actual antennas employed in the system.

Magnetic nanoparticles have been recently proposed as a contrast agent for breast cancer microwave imaging. In this communication, we report on the ongoing activities aiming at the feasibility validation of magnetic nanoparticles enhanced microwave imaging. In particular, we discuss the results of some experiments, carried out to deal with the factors that influence the detection limits of the technique. Previous experiments have shown that a major limitation to the minimum amount of contrast agent that can be appreciated is due to the instrumental drift, which cannot be overcome by simply averaging the measurements. In addition, owing to the low level of the useful signal, possible magnetic effects arising from the system and the involved media can become relevant and impair the measurements. In the following, we deal with these aspects and present the results of a first set of experiments aimed at assessing the detection capabilities of the technique.

This paper presents a novel approach to microwave hyperthermia exploiting magnetic nanoparticles as focusing agents, and reports the results of a 2D numerical study aimed at preliminarily assessing its effectiveness. The approach exploits magnetic nanoparticles, locally supplied to the tumor, to induce, through an external polarizing magnetic field, a detectable variation of its magnetic contrast. This variation is exploited to determine the excitations of the antenna array focusing the electromagnetic energy on the tumor. The advantage is that the synthesis of the excitations does not require any information neither on the geometry nor on the electromagnetic properties of the treated region, thus achieving totally blind field focusing. The magnetic nature of the magnetic nanoparticles contrast has required the development of an ad-hoc synthesis strategy, which, together with the use of magnetic nanoparticles, represents the novelty of the approach.

Magnetic nanoparticles (MNP) enhanced microwave imaging has been recently proposed as a tool to pursue the diagnostics of breast cancer in an effective and reliable way. By means of a numerical analysis carried out under realistic conditions, this letter aims at assessing the measurement dynamic range (i.e., the measurement resolution), in terms of tumor size, nanoparticles concentration, and working frequency, required for an apparatus based on this diagnostic approach.

In the framework of medical applications of microwaves, magnetic nanoparticles enhanced microwave imaging represents a promising diagnostic modality. As a matter of fact, it merges the safety, low-cost and portability of microwave technology with the increased specificity enabled by the selective targeting capability of magnetic nanoparticles. In particular, a key ingredient of this technique is the possibility of modulating the response of nanoparticles in the microwave range by means of an external polarizing magnetic field. To this end, the amplitudes of the polarizing field have to be properly set, in order to achieve optimal performances. In this communication, we present an experimental study aimed at optimizing the working conditions in terms of field strength of a ultra-wide band radar system for detecting a magnetic nanoparticle induced contrast.

This paper proposes a new formula for the operator $\mathcal {K}$ given by the product of the radiation operator by its adjoint. The formula expresses $\mathcal {K}$ by means of a surface integral, extended to the boundary of the source domain, rather than a volume integral, extended to the whole source domain, as entailed by its mathematical definition. As a result, the computation of $\mathcal {K}$ becomes much less onerous than the computation based on its mathematical definition. An immediate application of the derived formula is the fast computation of the singular value decomposition of the radiation operator, through to the fast computation of $\mathcal {K}$ . Some possible implications of the derived formula for $\mathcal {K}$ are also discussed. Finally, numerical examples are provided as proof of the validity and effectiveness of the formula.

The use of contrast agents is gaining a huge interest in microwave imaging (MWI) of breast cancer [1]–[3] in order to discriminate the response of cancerous tissues from that of the surrounding healthy tissue, and so to reduce the occurrence of false negatives arising from the low contrast between the electric properties of cancerous and fibro-glandular tissues [4]. To this end, magnetic nanoparticles (MNPs) represent a viable and effective choice [5], [6]. Indeed, they are allowed for clinical use and can be functionalized with biological molecules able to selectively bind to cancerous cells. Moreover, the microwave magnetic response of the MNPs can be properly modulated by applying an external polarizing magnetic field (PMF), without significantly influencing the response of the surrounding healthy tissue. As a result, by exploiting a proper differential measurement strategy, one can separate the response of the background from that of the MNPs (i.e., the “useful” signal), which, if present, is unambiguously associated to the presence of a malignant lesion [5].

A new technique, exploiting magnetic nanoparticles as contrast agent, has been recently proposed for microwave breast cancer imaging. As human tissues are non magnetic, the adoption of a magnetic contrast agent, able to selectively target tumoral cells, represents an effective means to increase diagnostic reliability. Although the effectiveness of the new technique has been fully assessed through realistic and accurate numerical simulations, an experimental proof-of-concept is still needed to set the ground for a subsequent pre-clinical stage. In this communication, we present the first results of such an experimental validation, performed with an ad hoc designed laboratory set-up and exploiting a realistic (although simplified) breast phantom.

Purpose: This paper presents a numerical study aiming at assessing the effectiveness of a recently proposed optimisation criterion for determining the optimal operative conditions in magnetic nanoparticle hyperthermia applied to the clinically relevant case of brain tumours. Materials and methods: The study is carried out using the Zubal numerical phantom, and performing electromagnetic–thermal co-simulations. The Pennes model is used for thermal balance; the dissipation models for the magnetic nanoparticles are those available in the literature. The results concerning the optimal therapeutic concentration of nanoparticles, obtained through the analysis, are validated using experimental data on the specific absorption rate of iron oxide nanoparticles, available in the literature. Results: The numerical estimates obtained by applying the criterion to the treatment of brain tumours shows that the acceptable values for the product between the magnetic field amplitude and frequency may be two to four times larger than the safety threshold of 4.85 × 108A/m/s usually considered. This would allow the reduction of the dosage of nanoparticles required for an effective treatment. In particular, depending on the tumour depth, concentrations of nanoparticles smaller than 10 mg/mL of tumour may be sufficient for heating tumours smaller than 10 mm above 42 °C. Moreover, the study of the clinical scalability shows that, whatever the tumour position, lesions larger than 15 mm may be successfully treated with concentrations lower than 10 mg/mL. The criterion also allows the prediction of the temperature rise in healthy tissue, thus assuring safe treatment. Conclusions: The criterion can represent a helpful tool for planning and optimising an effective hyperthermia treatment.

The paper deals with Magnetic NanoParticle Hyperthermia and presents some results of an extensive numerical study aiming at assessing the effectiveness of a recently proposed criterion for the optimal choice of the magnetic field and nanoparticle features, with reference to the clinically relevant case of brain tumors and exploiting 3D realistic models of human head.

Magnetic nanoparticle enhanced microwave imaging has been recently proposed as an effective strategy to monitor breast cancer. In this communication, we describe the ongoing activities concerned with a first experimental feasibility assessment of this technique. Such an activity aims at providing a proof-of-concept in realistic working conditions and it is obviously necessary to proceed towards the stage of pre-clinical trials.

The paper suggests a novel blind focusing approach for microwave hyperthermia. The idea is to exploit a contrast variation induced in the diseased tissue for the synthesis of the excitations of the antenna array employed for the field focusing, by performing a differential scattering measurement. In particular, the excitation vector is set as the right singular vector associated to the largest singular value of the differential scattering data matrix, obtained as the difference of the scattering matrixes measured, by the antenna array itself, before and after the contrast change. The approach is computationally effective and totally blind, not requiring any a priori knowledge on the electric and geometric features of the region hosting the target and on its spatial location with respect to the antenna array.

Magnetic nanoparticles (MNP) enhanced microwave imaging (MWI) has been recently proposed as an effective technique for breast cancer monitoring. In this communication, we discuss some issues related to the actual feasibility of a device for MNP enhanced MWI, such as the required dynamic range and the system's optimization in terms of antennas' typology and positioning.

The communication deals with Microwave Imaging (MWI) of breast cancer and aims at investigating the feasibility of an approach, recently proposed, which exploits Magnetic Nanoparticles (MNP) as magnetic contrast agents selectively delivered to the tumor. The numerical study herein presented is mainly devoted to test the reconstruction capabilities of the approach in quasi realistic conditions. To this purpose, 3D anthropomorphic breast phantom and an experimental characterization of the MNP response have been considered.

This communication deals with a recently proposed methodology for breast cancer diagnosis. Such a strategy is based on the joint use of microwaves, as a non-invasive and non-toxic tool to probe cancer lesions, and of Magnetic NanoParticles (MNP). These latter are used as a biocompatible contrast agent able to selectively enhance the response of cancerous tissues by modifying their magnetic permeability. Key aspects of the strategy are the possibility to modulate the magnetic response of MNP by using a polarizing magnetic field and the capabilities of avoiding ambiguities in discriminating between cancerous and healthy tissues. This contribution aims at providing a feasibility assessment of this new methodology in quasi realistic conditions. To this purpose, a numerical analysis has been carried out, in which the MNP behavior has been modeled according to the results of an experimental characterization and the imaging problem has been simulated by considering malignant lesions lying into an anthropomorphic 3D breast phantom.

The paper deals with Magnetic NanoParticle Hyperthermia and aims at assessing the effectiveness of an optimization criterion for the choice of the exposure conditions and nanoparticle characteristics, recently proposed by some of the authors, in the more realistic case of electrically and thermally inhomogeneous tissues. Numerical results are reported, showing the effectiveness of the criterion in the case of spherical tumor embedded in multi-layered tissues of cylindrical shape