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Designing a multifunctional nanomaterial is always considered as a biggest concern in the field of nanomedicine which aims to promote versatile action in a single use from tracking to therapeutics. Therefore, metallic nanoparticles are well exploited as a major platform with the assemblage of surface modifications which can be effectively engaged for plenty of applications. Here, in this work, we have successfully amalgamated gold coated magnetite core-shell nanoparticles along with bio-functionalization of folic acid and doxorubicin to explore its possibility as a distinct nanocargo for cancer nanotheranostics. This unique combination of both magnetic and optical properties makes its function to be more precise. For example, in case of in-vitro drug-release studies more than 75% of drug moieties are released at acidic pH 5.4 and exactly fitting in first order rate kinetics. As gold shell retains the superparamagnetic nature of the core it exhibited high r2 values, and because of large relaxivities (r2/r1) ratio, they are confirmed as T2-weighted contrast agent by MRI. Finally, under microwave of 2.45 GHz exhibited enough heat which can induce both apoptosis & necrosis leading to cell death. Thus, we conclude that our nanoparticle can be a multitool for diagnosis and therapeutics for various human diseases.

The aim of this study is to assess the suitability of a micro-processing unit of motion analysis (MPUMA), for monitoring, reproducing, and tracking upper limb movements. The MPUMA is based on an inertial measurement unit, a 16-bit digital signal controller and a customized algorithm. To validate the performance of the system, simultaneous recordings of the angular trajectory were performed with a video-based motion analysis system. A test of the flexo-extension of the shoulder joint during the active elevation in a complete range of 120º of the upper limb was carried out in 10 healthy volunteers. Additional tests were carried out to assess MPUMA performance during upper limb tracking. The first, a 3D motion reconstruction of three movements of the shoulder joint (flexo-extension, abduction-adduction, horizontal internal-external rotation), and the second, an upper limb tracking online during the execution of three movements of the shoulder joint followed by a continuous random movement without any restrictions by using a virtual model and a mechatronic device of the shoulder joint. Experimental results demonstrated that the MPUMA measured joint angles that are close to those from a motion-capture system with orientation RMS errors less than 3º.

High intensity focused ultrasound is a thermal therapy method used to treat malignant tumors and other medical conditions. Focused ultrasound concentrates acoustic energy at a focal zone. There, temperature rises rapidly over 56 °C to provoke tissue necrosis. Device performance depends on its fabrication placing computational modeling as a powerful tool to anticipate experimentation results. Finite element method allows modeling of multiphysics systems. Therefore, induced heating was modeled considering the acoustic field produced by a concave radiator excited with electric potentials from 5 V to 20 V. Nonlinear propagation was neglected and a linear response between the acoustic fields and pressure distribution was obtained. Finally, the results showed that acoustic propagation and heating models should be improved and validated with experimental measurements.

Diabetes mellitus has become a global healthcare issue with incidence levels growing exponentially each year. Diabetic foot is one of the complications related with the ailment, and if it is not attended in time, it can progressively deteriorate to a condition that necessitates foot amputation. This study aimed to establish a non-invasive monitoring system for diabetic foot. This proposed system detects and classifies temperature differences in foot sole zones as ulcerous if >2.2 °C and necrotic if The system proposed in this paper combines step-by-step and end-to-end algorithms that compensate for the limitations in data and, at the same time, enhance performance. It uses deep-learning techniques to segment visible-spectrum images using a retrained Mask R-CNN model, which is adjusted with 141 images to segment foot soles. These results are used over the temperature matrix in order to isolate the foot sole temperatures. The visualisation and classification methods use step-by-step algorithms with comparisons of homologous foot sole regions, convolutions with a two-dimensional (2D) Gaussian function, filters that process and compare areas of 1.5 cm2 over each foot sole, and a thermal threshold to differentiate ulcerous from necrotic zones. The results illustrated a detection accuracy of 90% for ulcers and 88% for necrosis, while the labelled areas had an error of 7.05% and 10%, respectively. These results demonstrated that the system is capable of successfully detecting and visualising the specific temperature differences over samples under an uncontrolled environment.

The strongest therapeutic effects in ultrasonic physiotherapy are mainly produced at the first centimeters, i.e. close to the applicator surface and, in general, only in the near-field zone. The acoustic field produced in practice by this type of transducers differs from the classical models because the vibration distribution on the real transducer surfaces is non-uniform. However, neither models using uniform distribution, nor those using typical non-uniform distribution patterns for the source accurately represent the radiation of this kind of transducers. Although this therapy is widely used and many efforts have been made in experimentally studying the patterns of ultrasound radiation produced during physiotherapy applications (IEC-61689, 1998), additional modeling researches still would be needed in order to achieve improved models giving field patterns closer to the measured ultrasonic results. In this paper, acoustic patterns produced from two source radiation functions are proposed and evaluated for field modeling of physiotherapy applicators. Both the functions are approximations to the pressure distribution measured close to the emitting surface and they are based on the modulation of the classical simply-supported function using either sinusoidal or Bessel-type distributions. The simply-supported function is accounted for the radiator-fixing condition and the modulation function simulates the complex vibration distribution of this kind of transducer. The modulator Bessel function is based on reports about Bessel-type vibration distributions found in piezoelectric disk resonators. The use of a selected sinusoidal segment represents another analytical option for obtaining an approximated behavior of the measured data in a real applicator. Both the field models are implemented using the finite element method (FEM) to obtain the numerical solution of wave equation at each point in the radiated space. The solution is reached by considering axisymmetric radiation in attenuation-free media. The results indicate the viability of applying an adequate model for acoustic field calculation by simulating the radiating distribution on the emitting surface as either sinusoidal or Bessel-modulated functions. Models using both the functions describe reasonably real behaviors, but those based on Bessel functions are better correlated with the measurements. The results for three commercial applicators indicate the possibility of representing, with adequate verisimilitude, the acoustic field radiated by physiotherapy ultrasound transducers using linear combinations of Bessel profiles describing the radiation source.

This paper introduces electronic tongue systems for remote environmental monitoring applications. This new approach in the chemical sensor field consists of the use of an array of non-specific sensors coupled with a multivariate calibration tool which may form a node of a sensor network. In our work, the proposed arrays were made up of potentiometric sensors based on polymeric membranes, and the subsequent cross-response processing was based on a multilayer artificial neural network model. Two cases are described: the environmental monitoring of ammonium pollutant plus alkaline ions at different measuring sites in the states of Mexico and Hidalgo (Mexico), and the monitoring of heavy metals (Cu^2^+, Pb^2^+, Zn^2^+ and Cd^2^+) in open air waste streams and rivers heading down the Gulf of Mexico.

During hyperthermia treatments, for determining internal temperature by using non-invasive ultrasound estimation, it is necessary to know some tissue ultrasonic characteristics around the hyperthermia range. The aim of this work was to determine in detail the changes of some ultrasonic properties (velocity and attenuation) of muscle, fat and liver tissues in the specific range of 26 °C to 50 °C. We proposed an experimental setup which allows minimizing the expansion effects in the biological samples. The ultrasonic signal passes through tissue and it is reflected by a 1-mm needle arrangement, inserted in the tissue sample. The results in the propagation speed behaviour, for the three studied tissues, appear to be quasi-linear with temperature changes. The attenuation coefficients are also presented for different temperatures.

Optimization of efficiency in hyperthermia requires a precise and non-invasive estimation of internal distribution of temperature. Although there are several research trends for ultrasonic temperature estimation, efficient equipments for its use in the clinical practice are not still available. The main objective of this work was to research about the limitations and potential improvements of previously reported signal processing options in order to identify research efforts to facilitate their future clinical use as a thermal estimator. In this document, we have a critical analysis of potential performance of previous ultrasonic research trends for temperature estimation inside materials, using different processing techniques proposed in frequency, time and phase domains. It was carried out in phantom with scatterers, assessing at their specific applicability, linearity and limitations in hyperthermia range. Three complementary evaluation indexes: technique robustness, Mat-lab processing time and temperature resolution, with specific application protocols, were defined and employed for a comparative quantification of the behavior of the techniques. The average increment per degrees C and mm was identified for each technique (3 KHz/ degrees C in the frequency analysis, 0.02 rad/ degrees C in the phase domain, while increments in the time domain of only 1.6 ns/ degrees C were found). Their linearity with temperature rising was measured using linear and quadratic regressions and they were correlated with the obtained data. New improvements in time and frequency signal processing in order to reveal the potential thermal and spatial resolutions of these techniques are proposed and their subsequent improved estimation results are shown for simulated and measured A-scans registers. As an example of these processing novelties, an excellent potential resolution of 0.12 degrees C into hyperthermia range, with near-to-linear frequency dependence, could be achieved. Specifically defined "numerical" and physical multi-scatter phantoms are described, which mimic ultrasound velocity in tissues of about 1560 m/s @ 35 degrees C and have a quasi-uniform internal scattering structure designed to assure standard signal patterns adequate for processing comparisons in the same time and sound velocity conditions for all the techniques analyzed, and to obtain easily repeatable multi-pulse echo-patterns. A perfect lineal dependence (100% of correlation coefficient) between the unitary average increment measured by each technique and temperature rising was observed while working with simulated A-scan registers, where all the parameters are under an accurate control. Nevertheless a very small quadratic tendency appeared in the results obtained from experimental echo registers, which are more similar to a real tissues case. It would be an interesting future work to analyze the behavior of these techniques in real tissues in order to confirm or reject this light quadratic tendency. Finally, new methods were detailed and applied in order to precisely quantify the advantages of each estimation technique; their respective intrinsic limitations were also underlined.

This work describes a voltammetric electronic tongue, in which the quantitative information contained in voltammograms obtained from amperometric sensors is firstly extracted employing the discrete wavelet transform (DWT) and then processed employing artificial neural networks (ANNs). The analytical case studied is the direct determination of the oxidizable aminoacids tryptophan, cysteine and tyrosine, and its application in the direct measurement of these amino acids in animal feed samples. A conventional voltammetry cell with a Pt working electrode is the experimental set-up and differential pulse voltammetry the selected technique. Due to the complexity of the obtained signals, the DWT pre-treatment was needed in order to eliminate noise components and compress voltammograms by selecting and extracting significant information. The ANN was subsequently used to model the system departing from the reduced information, and obtaining the concentrations of the considered species. Best results were obtained when using two hidden layers in a backpropagation neural network trained with the Bayesian regularization algorithm.

Because stable chronic recordings of electromyographic (EMG) signals are being required in the clinical practice, electrical impedance in the electrode–skin interface and the electrode–muscle location, must be maintained unmodified. However, because of some factors, these requirements have not been completely fulfilled. Implantable electrodes represent an alternative solution to inherent problems associated with conventional surface electrodes. In this work, an in vivo evaluation of the impedance of implanted electrodes developed for chronic recordings in rabbit is presented. The fibrous tissue formed around the implanted electrodes and affixation maintain the electrode in location. Two types of electrode configuration were evaluated: bipolar and multipolar. Seven months after implantation of the bipolar electrode, values of impedance were stable. In contrast, impedance at low frequency (0.5 and 1.0 Hz) of the multipolar configuration did not achieve stability.

Histological studies were carried out to evaluate long-term tissue biocompatibility of implanted materials which are commonly used to fabricate ISFET-devices sensitive to pH. Silicon nitride was the ion-sensitive material. Three experimental series were performed. The first consisting of three rabbits and the second of eight, both during 7 days of implantation, and the third consisting of four animals for 8 weeks of implantation. Teflon containers were used to limit movements of the samples. Glass was used as a control material and a P -type semiconductor with a deposited 900 Angstroms layer of silicon nitride was used as the experimental sample. Biocompatibility was assessed through the study of the local inflammatory response and by performing a differential count of the cells accumulated in the implanted chambers that contained the glass or the silicon nitride deposit. There were no significant differences between the local tissue reaction, either acute or chronic one, to the control or the experimental materials. These results suggest that silicon nitride has an adequate biocompatibility for a period of time that makes these sensors suitable for long-term and continuous in vivo measurements.

A new fabrication method for ion-sensitive field-effect transistors (ISFETs) with back contacts has been developed. The connections between the drain and the source diffusions and the back contacts are achieved by diffusing impurities from both sides of the wafer, until a conductive path has been formed through the thickness of the wafer. After these conductive paths are built, an FET structure is constructed on the front face of the chip. The back access allows for a clean face where the chemically active gate is placed. This contrasts with more traditional devices where the gate and the contacts are placed on the same face of the transistor. It is also set apart from devices featuring back contacts with anisotropically etched pits that require a different processing laboratory separated from the main clean-room facilities. The aim of the present work is to produce ISFET-based chemical sensors with back contacts featuring a clean technology using standard silicon foundry facilities. These sensors are more compact, easier to encapsulate and with a longer lifetime when compared to devices produced with more traditional structures.