High-Fidelity sEMG Signals Recorded by an on-Skin Electrode Based on AgNWs for Hand Gesture Classification Using Machine Learning.

The human forearm is one of the most densely distributed parts of the human body, with the most irregular spatial distribution of muscles. A number of specific forearm muscles control hand motions. Acquiring high-fidelity sEMG signals from human forearm muscles is vital for human-machine interface (HMI) applications based on gesture recognition. Currently, the most commonly used commercial electrodes for detecting sEMG or other electrophysiological signals have a rigid nature without stretchability and cannot maintain conformal contact with the human skin during deformation, and the adhesive hydrogel used in them to reduce skin-electrode impedance may shrink and cause skin inflammation after long-term use. Therefore, developing elastic electrodes with stretchability and biocompatibility for sEMG signal recording is essential for developing HMI. Here, we fabricated a nanocomposite hybrid on-skin electrode by infiltrating silver nanowires (AgNWs), a one-dimensional (1D) nano metal material with conductivity, into polydimethylsiloxane (PDMS), a silicone elastomer with a similar Young's modulus to that of the human skin. The AgNW on-skin electrode has a thickness of 300 µm and low sheet resistance of 0.481 ± 0.014 Ω/sq and can withstand the mechanical strain of up to 54% and maintain a sheet resistance lower than 1 Ω/sq after 1000 dynamic strain cycles. The AgNW on-skin electrode can record high signal-to-noise ratio (SNR) sEMG signals from forearm muscles and can reflect various force levels of muscles by sEMG signals. Besides, four typical hand gestures were recognized by the multichannel AgNW on-skin electrodes with a recognition accuracy of 92.3% using machine learning method. The AgNW on-skin electrode proposed in this study has great potential and promise in various HMI applications that employ sEMG signals as control signals.

Increasing sensitivity of coal analysis by gamma-albedo method.

The article deals with the methodological features of the gamma-albedo method and ways to increase sensitivity of measuring the coal ash content. On the basis of the developed mathematical model the inverse nature of sensitivity of the method is studied depending on the energy of primary gamma radiation. The need for a differentiated account of the nature of scattering that allows using a selective filter as a means of increasing sensitivity is revealed. It is shown that the qualitatively different nature of changing the mass coefficients of coherent and incoherent scattering of gamma radiation from its energy and effective atomic number allows increasing sensitivity of ash measurement according to the value of the ratio of coherently and incoherently scattered gamma radiation intensities. There is given the comparison of the sensitivity data for various modifications of the gamma-albedo method.

Express measurement of solid fuel ash content by nuclear gamma-method.

The methodological features of determining the ash content in coal using scattered gamma radiation are considered in the present study. Theoretical and experimental studies have shown that the integral intensity of secondary (scattered and fluorescent) radiation can serve as an instrumental signal depending on the quality of coal. To achieve a more unambiguous relationship between the integral radiation intensity and the ash content in coal of variable material composition, a compensation technique has been proposed consisting in artificial attenuating secondary radiation. The laws governing the integral intensity of radiation depending on the inverse thickness of the filter are studied, and the results are found to be invariant with variations in the ash composition. A model has been developed to optimize the filtering parameters of secondary radiation by considering the regularity of changes in the filter inversion thickness depending on the ash content.

Comparative Evaluation of ß-Catenin and E-Cadherin Expression in Liquid Aspiration Biopsy Specimens of Thyroid Nodules.

We compared the results of gene molecular and immunocytochemical studies of ß-catenin and E-cadherin in different variants of nodular thyroid disease (nodular colloid goiter, follicular thyroid adenocarcinoma, papillary thyroid cancer) and revealed changes of the function of the E-cadherin/ß-catenin complex leading to switching from adhesion function of ß-catenin in nodular colloid goiter to predominantly transcriptional activity in papillary carcinoma. The results confirm the important role of disturbances in E-cadherin-ß-catenin interactions in the mechanisms of malignant transformation of follicular epithelium.

[A rare combination of systemic scleroderma, sarcoidosis and psoriasis at advanced age].

We report a rare combination of systemic sclerosis, sarcoidosis, psoriatic arthritis and diverticulosis with severe complications in a 41-year-old male who has been treated by a rheumatologist since 10 years of age.