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Carasau bread is a flat bread, typical of Sardinia (Italy). The market of this food product has a large growth potential, and its industry is experiencing a revolution, characterized by digitalization and automation. To monitor the quality of this food product at different manufacturing stages, microwave sensors and devices could be a cost-effective solution. In this framework, knowledge of the microwave response of Carasau dough is required. Thus far, the analysis of the microwave response of Carasau doughs through dielectric spectroscopy has been limited to the dynamics of fermentation. In this work, we aim to perform complex dielectric permittivity measurements up to 8.5 GHz, investigating and modeling the role of water amount, salt and yeast concentrations on the spectra of this food product. A third-order Cole–Cole model was used to interpret the microwave response of the different samples, resulting in a maximum error of 1.58% and 1.60% for the real and imaginary parts of permittivity, respectively. Thermogravimetric analysis was also performed to support the microwave spectroscopy investigation. We found that dielectric properties of Carasau bread doughs strongly depend on the water content. The analysis highlighted that an increase in water quantity tends to increase the bounded water fraction at the expense of the free water fraction. In particular, the free water amount in the dough is not related to the broadening parameter γ2 of the second pole, whereas the bound water weight fraction is more evident in the γ2 and σdc parameters. An increase in electrical conductivity was observed for increasing water content. The microwave spectrum of the real part of the complex permittivity is slightly affected by composition, while large variation in the imaginary part of the complex dielectric permittivity can be identified, especially for frequencies below 4 GHz. The methodology and data proposed and reported in this work can be used to design a microwave sensor for retrieving the composition of Carasau bread doughs through their dielectric signature.

Magnetic biomaterials are multifunctional tools currently under investigation as theranostic platforms for biomedical applications. They can be implanted in bone tissue after bone cancer resection to perform local interstitial hyperthermia treatment. Given the requirements of high quality treatment, the hyperthermia therapy should be performed monitoring the system temperature, to avoid hot spots and control the treatment outcome. It is known that the magnetic properties of such implants vary with temperature. It is hypotesized that the treatment dynamic could be monitored using a microwave monitoring system. The variation of the electromagnetic properties of the biological tissues and the magnetic implant during the therapy would result in a different propagation of the microwave signal. This work investigates the feasibility of using microwaves to non-invasively monitor hyperthermia treatments with a simplified monodimensional propagation model. The forward problem is solved to identify the working frequencies, the matching medium properties and study several candidate materials. By using the numerical solutions from nonlinear and multiphysics simulations of the bone tumor hyperthermia treatment using magnetic scaffolds, the microwave signal propagation dynamic is studied. From our feasibility analysis, we found that it is possible to correlate the average tumor temperature with significant (~20 dB) variations in the transmission coefficient during a typical interstitial hyperthermia session using magnetic scaffolds. Our work brings together, for the first time, the electromagnetic material properties, the physio-pathology and physics of the hyperthermia treatment and the microwave propagation problem, thus paving the route for the development of an innovative theranostic system.

In this paper, a novel multi-layered waveguide-fed slotted cavity antenna array operating in the K-band (i.e., 18–27 GHz) is presented. The antenna is composed of 64 (8 × 8) groups of 2 × 2 subarrays with low profile, and fed by a 1–64 ways waveguide corporate-feed-network. In order to obtain a low sidelobe level (SLL), the Chebyshev power distribution is introduced into the feeding network to accurately taper the power distribution among the subarrays. To realize the amplitude-tapering network, a simple T-junction, which can provide equal phase but unequal power, is used. The antenna array is analyzed and validated by using the finite element method (FEM). Simulation results demonstrate that the proposed antenna array can achieve a broad bandwidth of 21.9%, and a good gain as 29.1 dBi. Additionally, the first SLL can be as small as −28.3 dB and −20 dB in the E-plane and the H-plane, respectively. The overall size of the slotted cavity antenna array is 169.6 × 169.6 × 7.23 mm3.

This work addresses the challenge of deriving a simple but effective multi-physic model useful for the design and simulation of hyperthermia devices for ensuring a high-quality treatment. An existing compact patch antenna working at 434 MHz is re-designed using the proposed methodology. The proposed general approach is used to investigate the specific case of the hyperthermia treatment of abdominal rhabdomyosarcoma. Instead of using patient-specific geometries with discrete vascular tree models, a surface phantom with a continuum 3D blood perfusion model of tumors is used. The geometrical parameters of the antennas are selected to provide a robust design against the variation of the phantom parameters. The effectiveness of the antenna is evaluated simulating the treatment with a recent non-linear multi-physic model, considering the different description of tumor vasculature. A more robust and effective design is obtained, with respect to its previous version. Indeed, the antenna bandwidth is increased with about 7%. The treatment performed using the old version of the antenna lead to unsuccessful results (40 °C after 60 min), whilst the novel robust design could successfully treat the target region. The new version of the patch can withstand a temperature of 42.5 °C for 60 min of treatment. To further enhance the effectiveness of the treatment, the use of a time-modulated power is studied. The proposed model could be extended to different body regions and used to develop an application-oriented design of antennas for hyperthermia treatment.

In this paper we present a blockchain based system for the supply chain management of a particular Italian bread. Goal of the system is to guarantee a transparent and auditable traceability of the Carasau bread where each actor of the supply chain can verify the quality of the products and the conformity to the normative about the hygienic-sanitary conditions along the chain. To realize this system we relied on the Blockchain and the Internet of Thing technologies in order to provide a trustless environment, in which trust is placed in cryptography, in mathematical operations and on the network, and not in public or private companies. Thanks to the use of digital technologies the system aims to reduce the data entry errors and the risk of tampering. Our system is designed so that along the supply chain, the nodes equipped with several sensors directly communicate their data to Raspberry Pi units that elaborate and transmit them to Interplanetary File System and to the Ethereum Blockchain. Furthermore, we designed ad hoc Radio Frequency Identification and Near Field communication tags to shortly supply the proposed system with information about the products and batches. The dedicated RFID tags robustness during on-bread operation was numerically tested. The system will easily allow end consumers to have a transparent view on the whole journey from raw material to purchased final product and a supervisory authority to perform online inspections on the products’ quality and on the good working practices.

In this paper, a microwave imaging approach based on artificial neural networks (ANNs) for neck tumor detection is presented. The aim of this technique is to retrieve the geometric and dielectric properties of the neck to identify the possible presence of tumors, starting from scattered electric field data. A fully-connected neural network is developed to test the feasibility of the proposed approach. Moreover, a numerical model including the main features of a cross section of the neck is specifically designed in order to create a suitable training dataset. Subsequently, for the optimization of the ANN architecture and performance evaluation, a numerical analysis is conducted. A set of simulated cases, based on realistic neck phantoms, is tested to evaluate the robustness of the network. Preliminary results show the possibility to identify and locate neck tumors.

Through the advent of mobile cellular networks the number of radio base stations installed in urban environments has increased exponentially. As a consequence, the level of the electromagnetic (EM) field has increased at the same pace, sometimes approaching the limits set by the national rules. The first step of a compliance test campaign is the field estimation, mainly close to the base stations. In this article, the estimation of EM field generated by UHF base station is presented. A rephrasing of the COST 231 - Walfisch-Ikegami model is used to evaluate the path loss at distances greater than 20 m from the base station. Then, the knowledge of the full antenna pattern allows to estimate the field level. Since antenna manufacturers measure, and publish, only the patterns on the principal planes, an extrapolation procedure is also presented. A measurement campaign in the specific small urban and irregular environments of Dorgali (NU), Cala Gonone (NU) and Lunamatrona (CA), Italy, done in the context of Onde Chiare project, has been used to assess the approach presented here.

Several studies have shown the presence of fluoride levels much higher than the 1.5 mg/L threshold concentration recommended by WHO in the spring waters and wells of the Ethiopian Rift Valley. Available defluoridation techniques can be costly, present complicated technical aspects, and show limited effectiveness. Therefore, it is necessary to devise innovative, sustainable, and effective solutions. This study proposes an alternative method of intervention to the known techniques for removing fluoride from water, particularly suitable for smaller rural communities. In particular, in this work, the possibility to use electromagnetic fields as a physical method for removing the excess fluoride was investigated. The study was carried out by developing a multiphysics model used for studying and envisaging the design of a device. In this framework, the combination of this approach with the use of highly reactive smectite clay was numerically studied. The results obtained, although preliminary, indicate that the proposed system could significantly impoverish the waters of the Rift Valley from fluoride, with the consequence of obtaining a resource suitable for human consumption, in particular for rural communities. However, further theoretical investigations and experimental phases will be necessary to achieve the desired results.

Magneto-responsive biomaterials can play a key role in several biomedical applications, from therapeutic to diagnostic. Despite the several efforts for synthesizing and characterizing bioceramics doped with magnetic ions or polymers loaded with magnetic nanoparticles, there is lack of mathematical and numerical models capable of filling the gap between nanomaterial science and engineering. This work reviews and propose numerical, multiphysics models for studying the use of magnetic scaffolds for the hyperthermia treatment of bone tumors and for magnetically targeted drug delivery.

The effectiveness and the quality of the hyperthermia treatment of bone tumors using magnetic implants can be improved. To date, several biocompatible biomaterials loaded with magnetic nanoparticles have been manufactured and characterized. However, the intrinsic parameters of the so-called magnetic scaffolds are not tuned to perform an optimum hyperthermia treatment. This work, for the firs time, deals with the theoretical modeling of bone tumor hyperthermia using magnetic scaffolds. The goal is to investigate the heating abilities of a synthetic, virtual set of potential implants. The analysis is oriented in identifying the most essential features and relevant parameters for providing unique, useful feedbacks, form an electromagnetic engineering point of view, to material scientists and clinicians.

To avoid high recurrence rate, the hyperthermia treatment (HT) of bone tumors after surgical intervention was investigated. Innovative magnetic biomaterials can be used as thermoseeds to perform local thermal therapy. This work copes with the multiphysic modeling of the HT of residual Osteosarcoma (OS) cells using the so-called magnetic scaffolds. The goal is to develop a model that can serve as a tool to plan an accurate, safe, and high-quality treatment. Therefore, the electromagneto-thermal problem of radio-frequency heating is solved to determine the spatial and temporal evolution of the temperature field in a simplified 2-D geometry of proximal humerus. Different assumptions about the nonuniformity of the external magnetic field are verified. The possibility of nonideal distribution of magnetic nanoparticles in the biomaterial is accounted for the first time. The pattern of the magnetic field and of the induced electric field is studied. Moreover, the spatio-temporal evolution of temperature is investigated in the different cases. With these improvements to the state-of-the-art model of the HT of bone tumors, it was possible to identify the field parameter which allows to deliver the therapeutic thermal dose to OS cells.

Body channel communication (BCC) is a data transmission technique which uses the human body as communication channel. The availability of mathematical and physical models which can cope with the channel description is an open issue in the literature. In this work, a finite periodic transmission line model to describe the human body as transmission medium is proposed. Bio-impedentiometric measurements from 1 kHz and 1 MHz are carried out to estimate model parameters. The developed model has been validated with measurements carried out with a ground-referred and low-complexity system called Live Wire. A ±3% error for communication distances ranging from 20 to 150 cm was found. This contribution proposes a distributed model which can be used as framework for the design and for enhancing the performances of body channel communication systems.

Nowadays, the use of CubeSats for telecommunications and interplanetary missions is ever-increasing, thanks to their appealing low-cost character, as well as the space environment, which poses challenging multiphysics constraints on the antenna design. In this framework, the use of Ka-band for communication is explored. We present the design of a stacked patch antenna working across the down- and uplink Ka-bands. Materials and geometry of the radiator have been selected by accounting for the trade-off between electromagnetic, thermal and mechanical requirements. The design of the antenna is performed with a particle swarm optimization algorithm developed to control the bandwidth and matching. A bandwidth of 5.53@33.185 GHz has been obtained, with a gain around 8 dB. Furthermore, a multiphysics thermal analysis is performed to verify the operational stability of the optimized array, mounted on a 1 U satellite, in a case-study mission. The temperature patterns in the array are evaluated during the orbital period, and the influence of the operative temperature on the antenna responses and gain was considered. We found that the thermal loads can affect the antenna matching. However, thanks to the optimized design, the proposed stacked antenna can operate from −100 $^{\circ }$ C to 100 $^{\circ }$ C, with an almost constant gain. Finally, following a damage-tolerant approach, the level of mechanical deformation, which could be induced on the communication system, was studied. The stress analysis reveals that the stacked geometry can be used in a space mission. From the investigation of the strain and displacement field, we found a negligible impact on the antenna performance.

A microwave imaging approach for the diagnosis of neck diseases is proposed in this paper. Specifically, the case study of cervical myelopathy has been considered. The developed technique aims at retrieving the distributions of the dielectric properties of a cross section of the neck, from which information about the spinal canal size can be extracted. To this end, a new hybrid inversion procedure exploiting a qualitative delay-and-sum method together with a conjugate-gradient-like scheme developed in Lebesgue spaces has been used. The feasibility of the approach has been assessed by means of a prototype of measurement system equipped with ten bowtie-like antennas and using a simplified phantom. Preliminary experimental results are reported.

The digitalization challenges and high quality standards offered by Industry 4.0 to the traditional bread manufacturing sector calls for engineering solutions, such as wireless sensors network (WSN). In this work it is presented the long-term test and statistical analysis of the improvement of the hardware and software modules of an existing WSN for Carasau bread industry.

Magnetic biomaterials are powerful multifunctional tools in theranostic. They can be remotely controlled by an external magnetic field. When a radiofrequency field is used, the magnetic nano- or microparticles embedded in the biomaterial dissipate heat, which can be used for therapeutic purposes. Hyperthermia treatment of deep- seated tumors, such as bone cancers, can extensively benefit from the use of such class of magnetic responsive biomaterials. Therefore, in this work it is presented the numerical analysis of the hyperthermia treatment of secondary bone tumors performed using a magnetic hydroxyapatite prosthesis.

The estimation of the field levels generated by radio base stations set in urban environment is still urgent need and a relevant issue for the compliance to national regulations and for propagation concerns. This work copes with the estimation of electromagnetic field generated by UHF base stations in peculiar urban scenarios. To account for irregular geometries and to deal with the propagation in hilly town, the COST 231-Walfisch-Ikegami model is modified and rephrased in order to evaluate the path loss at distances greater than 20 meters from the base station in such peculiar urban environments. Measurements were carried out in the small urban and irregular built-up areas of Dorgali (NU), Cala Gonone (NU) and Lunamatrona (CA), Italy, to validate the model.

The exact and unambiguous knowledge of the dielectric and thermal properties of biological tissues, as well as tissue-mimicking phantoms, is of fundamental importance for the design of all types of microwave systems for both diagnostic and therapeutic purposes that have been taking place in recent years. Several research groups around the world have been studying the dielectric and thermal properties of biological tissues for several years and numerous databases have been proposed. This paper presents some preliminary results about a cross study on the dielectric and thermal properties of known solutions, in order to tune the measurement systems for the future analysis on more sophisticated tissue-mimicking mixtures. As an example of the possible set of measurements intended for such a study, two different setups are discussed. First, the impact on dielectric measurements of the system calibration temperature $(23^{\circ}\mathrm{C}$ and $80^{\circ}\mathrm{C})$, for a 0.1M NaCl solution, representative of tissues with an high water content, is outlined in the frequency range 0.5–30 GHz. Then, the thermal properties of sunflower oil, representative of tissues with a low water content, are characterized in a temperature range from $35^{\circ}\mathrm{C}$ to $45^{\circ}\mathrm{C}$.

This article deals with the numerical modeling of the multiphysics investigation of an electric-field-based device for the defluoridation of Ethiopian water to mitigate fluorosis while satisfying the World Health Organization quality requirement for potable water. A tubular reactor with metallic parallel plates, connected to a static voltage source, exerts an electric force on the ion in solution, attracting it to the electrodes. Meanwhile, the ion is drifted by the laminar water flow which, in turn, allows us to separate and collect the F $^{-}$ -rich stream from the potable one. In this system, the electrostatic problem and the mass transport are coupled according to the highly nonlinear modified Poisson–Nernst–Planck–Stokes equations system. Therefore, carefully modeling the dielectric permittivity, the ionic diffusivity, and mobility as function of fluoride concentration and temperature, the set of operating parameters to ensure the highest fluoride removal from Ethiopian thermal water is identified.

Magnetic resonance imaging (MRI) has the clinical potential of helping diagnosis in providing to doctors structural and functional information of several neurological disorders. In this study, we proposed a new method based on the elaboration of MR-Images and functional Magnetic Resonace Images (fMRI), combined with the explotation of Mini Mental Score Examination (MMSE) to discriminate Alzheimer’s Disease (AD) by control subjects using Support Vector Machine (SVM) classification. 69 subjects from the Alzheimer’s disease Neuroimaging Initiative (ADNI) open database, 33 AD patients and 36 healthy controls (HC), were analyzed. The use of a unimodal approach led to unsatisfactory results, whereas the multimodal approach, i.e., the combination of MRI, fMRI, and MMSE features, provided an accuracy of 95.65%, a specificity of 97.22%, and a sensibility of 93.39%.

Body channel communication (BCC) is a technique for data transmission exploiting the human body as communication channel. Even though it was pioneered about 25 years ago, the identification of a good electrical model behind its functioning is still an open research question. The proposed distributed model can then serve as a supporting tool for the design, allowing to enhance the performances of any BCC system. A novel finite periodic transmission line model was developed to describe the human body as transmission medium. According to this model, for the first time, the parasitic capacitance between the transmitter and the receiver is assumed to depend on their distance. The parameters related to the body and electrodes are acquired experimentally by fitting the bio-impedentiometric measurements, in the range of frequencies from 1 kHz to 1 MHz, obtaining a mean absolute error lower than 4° and 30Ω for the phase angle and impedance modulus, respectively. The proposed mathematical framework has been successfully validated by describing a ground-referred and low-complexity system called Live Wire, suitable as supporting tool for visually impaired people, and finding good agreement between the measured and the calculated data, marking a ±3% error for communication distances ranging from 20 to 150 cm. In this work we introduced a new circuital approach, for capacitive-coupling systems, based on finite periodic transmission line, capable to describe and model BCC systems allowing to optimize the performances of similar systems.

This works claims to define, via numerical simulations, magnetic field parameters to perform an effective in situ bone tumor hyperthermia treatment using magnetic scaffolds. A Cole-Cole model to describe the frequency response of the magnetic susceptibility of nanoparticles embedded in novel magnetic biomaterials is explored. The heating phenomenon is investigated, considering both the ischemic and inflamed state of the fracture gap at the bone/implants interface. Both Osteosarcoma and Fibrosarcoma tumors are analyzed. Magnetic hydroxyapatite and poly-ϵ-caprolactone scaffolds are investigated. From the thermal analysis, it is found that the fracture behaves as a resistance to heat conduction, and therefore, strength and frequency of external magnetic field has to be tuned to perform the treatment taking the fracture status into account. Moreover, numerical experiments indicate that low perfused Fibrosarcoma can be treated using moderate-strength field, whereas more intense external fields are required to treat strongly vascularized Osteosarcoma without damaging healthy bone tissue. Magnetic hydroxyapatite stands out to be the best performing and versatile material to treat both tumors. These simulations can be regarded as a starting point to analyze possible clinical use of magnetic scaffolds for in situ bone hyperthermia.

Agriculture is facing the challenge of increasing the quality of food production with environmentally friendly and health compatible processes featuring limited use of chemicals. The elimination of pathogens and harmful biological agents still remains a fundamental requirement. Therefore, soil physical disinfestation and disinfection represent a promising approach to a sustainable and profitable agriculture. For this reason, a cheap and selective method based on microwave power is proposed. Microwave soil disinfection is based on increasing the soil and, consequently, the pathogens temperature, by radiating the system with microwaves and maintaining the temperature over a threshold value for a sufficient time. This work deals with the nonlinear modeling of electromagnetic and heating phenomena involved in the soil disinfection. Thus, the feasibility of the proposed approach is demonstrated in a realistic case and an optimal design process is derived for any kind of soil.

Microwave hyperthermia is focused on raising the temperature of cancerous tissues a few degrees above the norm, in order to induce cellular death within the tumor but avoiding excessive heating of normal tissues, at the same time. The success of this therapy is based on the concurrence of different physics processes tied to the electromagnetic radiation, to the fluid dynamic and to the bio-heat transfer. However, the characteristics of the tumor play an important role in the delivery of the therapy. In this work an optimum design of microwave hyperthermia treatment, from a numerical point of view, is presented, taking into account the multi-physic coupling and a blood perfusion model of a muscle tissue tumor.

This work deals with the non-linear and multiphysic modeling of the hyperthermia treatment of bone tumors using novel biomaterials loaded with magnetic nanoparticles. The possible treatment of Osteosarcoma tumor with magnetic hydroxyapatite and poly-caprolactone doped with magnetite nanoparticles are analyzed. During the procedure, the materials and tissue physical properties modifies due to the heating, implying a coupled solution of thermal and electromagnetic equations. In the present study a numerical model, implemented using a commercial finite element software, is developed to include the intrinsic non-linearities of the hyperthermia multiphysic treatment. Therefore, an accurate in silico analysis is performed to identify the strength and frequency of the external magnetic field which would ensure an effective therapy, evaluated using the thermal dose damage analysis.