Stem Cell Therapy Enhances Motor Activity of Triceps Surae Muscle in Mice with Hereditary Peripheral Neuropathy

Impaired motor and sensory functions are the main features of Charcot–Marie–Tooth disease. Mesenchymal stem cell (MSCs) therapy is one of the possible treatments for this disease. It was assumed that MSCs therapy can improve the contractile properties of the triceps surae (TS) muscles in mice with hereditary peripheral neuropathy. Murine adipose-derived mesenchymal stromal cells (AD-MSCs) were obtained for transplantation into TS muscles of FVB-C-Tg(GFPU)5Nagy/J mice. Three months after AD-MSCs transplantation, animals were subjected to electrophysiological investigations. Parameters of TS muscle tension after intermittent high frequency electrical sciatic nerve stimulations were analyzed. It was found that force of TS muscle tension contraction in animals after AD-MSCs treatment was two-time higher than in untreated mice. Normalized values of force muscle contraction in different phases of electrical stimulation were 0.3 ± 0.01 vs. 0.18 ± 0.01 and 0.26 ± 0.03 vs. 0.13 ± 0.03 for treated and untreated animals, respectively. It is assumed that the two-fold increase in TS muscle strength was caused by stem cell therapy. Apparently, AD-MSCs therapy can promote nerve regeneration and partial restoration of muscle function, and thus can be a potential therapeutic agent for the treatment of peripheral neuropathies.     

Effect of Inlet Diameter on the Performance of a Filtering Hydrocyclone Separator

An innovative hydrocyclone was designed, in which a conical filtering wall replaces the conical section, producing another liquid stream leaving the equipment, besides underflow and overflow streams. The influence of the inlet diameter of a filtering hydrocyclone was analyzed by an experimental and computational fluid dynamics study. Data from conventional hydrocyclones of the same configurations were also obtained. Under identical operating conditions and geometry, the filtering hydrocyclone presented a better performance than the conventional device. Under the experimental conditions evaluated, an about twofold increase in inlet diameter reduces the Euler number significantly.     

Resonant phenomena in laser excitation of surface waves on solids

Excitation of surface waves by a moving laser beam has been studied both theoretically and experimentally. Using periodic surface structures as an example, it is demonstrated that the type of excited wave and the rate of its growth depend resonantly on the beam velocity. Experimental data show that resonant excitation of different periodic surface structures can change the spatial distribution of the absorbed laser energy     

Optimization of Design and Performance of Solid‐Liquid Separators: A Thickener Hydrocyclone

Studies on hydrocyclones have evolved over recent years and various configurations of this device have been proposed in the literature for different purposes. Herein, an innovative geometrical configuration of hydrocyclones was developed by means of the response surface technique, combined with an optimization algorithm and supported by a computational fluid dynamics complementary study. The results obtained with these optimization techniques were validated by experimental data. The optimized hydrocyclone configuration is characterized by low energy consumption, i.e., low Euler number, with a small underflow‐to‐throughput ratio and can be used as a thickener hydrocyclone.     

Long‐duration fully autonomous operation of rotorcraft unmanned aerial systems for remote‐sensing data acquisition

Recent applications of unmanned aerial systems (UAS) to precision agriculture have shown increased ease and efficiency in data collection at precise remote locations. However, further enhancement of the field requires operation over long periods of time, for example, days or weeks. This has so far been impractical due to the limited flight times of such platforms and the requirement of humans in the loop for operation. To overcome these limitations, we propose a fully autonomous rotorcraft UAS that is capable of performing repeated flights for long‐term observation missions without any human intervention. We address two key technologies that are critical for such a system: full platform autonomy to enable mission execution independently from human operators and the ability of vision‐based precision landing on a recharging station for automated energy replenishment. High‐level autonomous decision making is implemented as a hierarchy of master and slave state machines. Vision‐based precision landing is enabled by estimating the landing pad's pose using a bundle of AprilTag fiducials configured for detection from a wide range of altitudes. We provide an extensive evaluation of the landing pad pose estimation accuracy as a function of the bundle's geometry. The functionality of the complete system is demonstrated through two indoor experiments with duration of 11 and 10.6 hr, and one outdoor experiment with a duration of 4 hr. The UAS executed 16, 48, and 22 flights, respectively, during these experiments. In the outdoor experiment, the ratio between flying to collect data and charging was 1–10, which is similar to past work in this domain. All flights were fully autonomous with no human in the loop. To our best knowledge, this is the first research publication about the long‐term outdoor operation of a quadrotor system with no human interaction.     

An examination of effects of solidification parameters on permeability of a mushy zone in castings

A model describing the development of dendritic structure and the resulting gradient of flow resistance to interdendritic liquid is presented. The Hagen–Pousielle version of D’Arcy’s equation for flow through a porous structure is developed as a function of cooling rate and liquid volume fraction. Applied to finite elements in a unidirectionally cooled casting model, permeability gradient, feeding flow-rate required to prevent porosity, and mushy-zone liquid pressure drop at this flow rate are evaluated for the simple Fe–2Cr–0.5C and Al–5Cu castings exhibiting asymptotic and linear temperature profiles, respectively. The model shows permeability of the dendritic structure in the mushy zone dropping sharply, approaching the root of solidification front (solidus). Also shown is the effect of relative magnitude of primary and secondary arm spacing. If secondary dendrite arm spacing approaches primary arm spacing, the permeability for flow normal to primary dendrite arms approaches or even surpasses the permeability for flow parallel to primary dendrite arms.     

Metric classification of early Parkinsonism in the space of electroencephalographic features

This paper considers the problem of metric classification of early Parkinsonism in the feature space of multi-channel signals of electroencephalography (EEG). The electroencephalography feature space includes both spectral characteristics and features of rhythmic disorganization. A model of logistic regression for the classification of early Parkinsonism is studied. The model was trained on the data obtained from the experimental EEG studies in a group of patients in the 1st stage of Parkinson’s disease and a control group of subjects. Analysis of the classification logistic model was carried out using the data from 38 subjects, including 22 subjects from the control group and 16 patients in the first stage of Parkinson’s disease. Dependencies of the recall on the functional value for the control group and the patients and classification accuracies are calculated.