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In multiple sclerosis, while remarkable progress has been accomplished to control the inflammatory component of the disease, repair of demyelinated lesions is still an unmet need. Despite encouraging results generated in experimental models, several candidates favouring or promoting remyelination have not reached the expected outcomes in clinical trials. One possible reason for these failures is that, in most cases, during preclinical testing, efficacy was evaluated on histology only, while functional recovery had not been assessed. We have generated a Xenopus laevis transgenic model Tg(mbp:GFP-NTR) of conditional demyelination in which spontaneous remyelination can be accelerated using candidate molecules. Xenopus laevis is a classic model for in vivo studies of myelination because tadpoles are translucent. We reasoned that demyelination should translate into loss of sensorimotor functions followed by behavioural recovery upon remyelination. To this end, we measured the swimming speed and distance travelled before and after demyelination and during the ongoing spontaneous remyelination and have developed a functional assay based on the visual avoidance of a virtual collision. Here we show that alteration of these functional and clinical performances correlated well with the level of demyelination and that histological remyelination, assayed by counting in vivo the number of myelinating oligodendrocytes in the optic nerve, translated in clinical–functional recovery. This method was further validated in tadpoles treated with pro-remyelinating agents (clemastine, siponimod) showing that increased remyelination in the optic nerve was associated with functional improvement. Our data illustrate the potential interest of correlating histopathological parameters and functional–clinical parameters to screen molecules promoting remyelination in a simple in vivo model of conditional demyelination.

The influence of reflective Bragg gratings that are formed in an active medium due to the spatial periodic modulation of gain on the spectral properties of lasing are investigated by an example of a pulsed Nd : YAG laser. It is shown that, at a certain choice of the formation regime of reflective gratings of gain, the lasing bandwidth can be reduced by a factor of 3 – 5, with a corresponding increase in the pulse energy and significant improvement of spatial beam quality.

A single-phase physico-mathematical model of a high-speed waterjet forming process that uses the underwater abrasive waterjet cutting technology while an abrasive-liquid flow under a pressure ranging from 60 to 80 MPa passes through the jet-forming path of a mobile abrasive waterjet machine has been developed. The results of a numerical experiment are presented. It has been shown that the main structural parameters of the internal profile of the jet-forming element (the profile of the focusing cavity, diameter and length of the output-channel) influence the geometric and kinematic parameters of the formed jet and the consumption of the hydro-abrasive suspension.

Се-doped (Pb,Gd)3(Al,Ga)5O12 single crystalline garnet films were grown using liquid-phase epitaxy from four series of supercooled PbO–B2O3-based melt solutions on Gd3Ga5O12 and Gd3Al2.26Ga2.74O12 single crystal substrates. The optical and scintillation properties of the epitaxial garnet films were studied. The 5d-4f emission of Ce3+ ions within 450–650 nm was observed. The highest pulsed cathodoluminescence yield and scintillation yield values under 133Ba excitation for the Pb0.01Ce0.02Gd2.97Al3.13Ga1.87O12 film were 43,100 photons/MeV and 20,000 photons/MeV, respectively. The pulsed cathodoluminescence decay times of the film were 1.8 (1%), 24 (25%), and 60 ns (74%), and the scintillation decay times were 3.9 (7%) and 43.6 ns (93%). Because of the rapid decay and high light yield, Се-doped (Pb,Gd)3(Al,Ga)5O12 garnet films can be used in X-ray scintillators for different applications, such as homeland security.

Drafting in Magic the Gathering is a sub-game within a larger trading card game, where several players progressively build decks by picking cards from a common pool. Drafting poses an interesting problem for game and AI research due to its large search space, mechanical complexity, multiplayer nature, and hidden information. Despite this, drafting remains understudied, in part due to a lack of high-quality, public datasets. To rectify this problem, we present a dataset of over 100,000 simulated, anonymized human drafts collected from Draftsim.com. We also propose four diverse strategies for drafting agents, including a primitive heuristic agent, an expert-tuned complex heuristic agent, a Naive Bayes agent, and a deep neural network agent. We benchmark their ability to emulate human drafting, and show that the deep neural network agent outperforms other agents, while the Naive Bayes and expert-tuned agents outperform simple heuristics. We analyze the accuracy of AI agents across the timeline of a draft, and describe unique strengths and weaknesses for each approach. This work helps to identify next steps in the creation of humanlike drafting agents, and can serve as a benchmark for the next generation of drafting bots.

Escape behaviors, orienting reflexes, and social behaviors in

We demonstrate an instrument for high-precision measurements of parts manufactured with selective laser sintering systems. Operation concept is based on obtaining digital holograms of the surfaces of each layer of the part in the process of layer-by-layer sintering with subsequent processing of the obtained data and reconstruction of the internal structure and external surface of the part. Limitations of accuracy, field of view and spatial resolution are demonstrated. We demonstrate a system with less than 10 µm altitude spatial resolution with further improvement up to 1 µm. Field of view obtained is 300 mm2. Surface spatial resolution up to 100 µm is demonstrated. Compactability of system allows it to be installed in many laser sintering systems.

In the present paper, we experimentally study the diffusive dynamics in ensembles of self-propelled and self-rotating bristle-bots. Considering the dependence of the system dynamics on the packing density of robots as well as on the friction between individual robots, we show that the friction slightly affects the diffusive dynamics but leads to a significant change in the jamming transition corresponding to the formation of rigid clusters of robots.

In teaching, the best exam questions are those that seem simple at first but can lead to deep and nuanced conversations. Similarly, to probe brain development, we should look for behaviors that are easy to evoke and quantify, but that are demanding, malleable, and inherently variable. Visual collision avoidance is an example of such a behavior; it is ecologically relevant, robust, and easy to record, but also nuanced and shaped by the sensory history of the animal. Here we describe how to set up a visual avoidance assay and how to use it to test sensory processing and sensorimotor transformations in the vertebrate brain.

We substantiate the recommendations for improving the efficiency of hydro- and hydroabrasive cutting of the honeycomb structures that are widely used in aircraft and rockets, obtained by numerical solving of the spatial dynamic problem with allowance for the physico-mechanical and kinematic parameters of a high-speed jet, the physico-mechanical and structural parameters of the treated honeycomb structure, and the parameters of the technological treatment (feeding and the impact angle of the jet with the face surface of the blanks). A physico-mathematical model and a method of numerical analysis of the process have been developed. The influence of the above parameters on the quality of the surfaces of the treated blanks is illustrated. The results of the calculations are compared with the experimental data.