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Majority of stroke survivors are left with poorly functioning paretic hands. Current rehabilitation devices have failed to motivate the patients enough to continue rehabilitation exercises. The objective of this project, MIDAS (Multi-sensorial Immersive Dynamic Autonomous System) is a proof of concept by using an immersive system to improve motivation of stroke patients for hand rehabilitation. MIDAS is intended for stroke patients who suffer from light to mild stroke. MIDAS is lightweight and portable. It consists of a hand exoskeleton subsystem, a Virtual Reality (VR) subsystem, and an olfactory subsystem. Altogether, MIDAS engages four out of five senses during rehabilitation. To evaluate the efficacy of MIDAS a pilot study consisting of three sessions is carried out on five stroke affected patients. Subsystems of MIDAS are added progressively in each session. The game environment, sonic effects, and scent released is carefully chosen to enhance the immersive experience. 60% of the scores of user experience are above 40 (out of 56). 96% Self Rehabilitation Motivation Scale (SRMS) rating shows that the participants are motivated to use MIDAS and 87% rating shows that MIDAS is exciting for rehabilitation. Participants experienced elevated motivation to continue stroke rehabilitation using MIDAS and no undesired side effects were reported.

With the possible spacial association to the Fermi/LAT source 3FGL J1330.0-3818, TOL 1326-379 may be the first one that is identified as a gamma-ray emitting Fanaroff-Riley type 0 radio galaxy (FR0 RG). We analyze the ~12 yr Fermi/LAT observation data of this gamma-ray source and examine its association to TOL 1326-379. We show that the gamma-ray source (named as J1331.0-3818) is tentatively detected with a TS value of 28.7, 3FGL J1330.0-3818 is out of the 95% containment of J1331.0-3818, and their positions are spatially separated ~0.2 degr. 4FGL J1331.3-3818 falls into the 68% containment of J1331.0-3818, suggesting that our result agrees with that reported in the Fourth Fermi LAT Source Catalog. TOL 1326-379 is out of the 95% containment of J1331.0-3818, and their positions are spatially separated ~0.4 degr, indicating that the association between J1331.0-3818 and TOL 1326-379 is quite ambiguous. However, we do not find other possible potential radio or X-ray counterpart within the circle centered at J1331.0-3818 with a radius of 0.4 degr. The spectral energy distribution (SED) of TOL 1326-379 shows a bimodal feature as seen in the gamma-ray emitting RGs. We fit the SED with the one-zone leptonic model and find that the average energy spectrum of J1331.0-3818 agrees with the model prediction. Assuming that J1331.0-3818 is an unidentified gamma-ray source, we derive the upper-limit of the gamma-ray flux for TOL 1326-379. It is not tight enough to exclude this possibility with the SED modeling. Based on these results, we cautiously argue that the gamma-ray source J1331.0-3818 is associated with TOL 1326-379 and its jet radiation physic is similar to those gamma-ray emitting RGs., Comment: 14 pages, 6 figures, accepted for publication in RAA

This paper presents a stochastic three-dimensional focused transport simulation of solar energetic particles (SEPs) produced by a data-driven coronal mass ejection (CME) shock propagating through a data-driven model of coronal and heliospheric magnetic fields. The injection of SEPs at the CME shock is treated using diffusive shock acceleration of post-shock suprathermal solar wind ions. A time-backward stochastic simulation is employed to solve the transport equation to obtain the SEP time–intensity profile at any location, energy, and pitch angle. The model is applied to a SEP event on 2020 May 29, observed by STEREO-A close to ∼1 au and by Parker Solar Probe (PSP) when it was about 0.33 au away from the Sun. The SEP event was associated with a very slow CME with a plane-of-sky speed of 337 km s−1 at a height below 6 RS as reported in the SOHO/LASCO CME catalog. We compute the time profiles of particle flux at PSP and STEREO-A locations, and estimate both the spectral index of the proton energy spectrum for energies between ∼2 and 16 MeV and the equivalent path length of the magnetic field lines experienced by the first arriving SEPs. We find that the simulation results are well correlated with observations. The SEP event could be explained by the acceleration of particles by a weak CME shock in the low solar corona that is not magnetically connected to the observers.

Gas electron multiplier(GEM) detector is used in Cosmic Muon Scattering Tomography and neutron imaging in the last decade. In this work, a triple GEM device with an effective readout area of 10 cm X 10 cm is developed, and an experiment of discriminating between cosmic muon and x-ray based on rising time is tested. The energy resolution of GEM detector is tested by 55Fe ray source to prove the GEM detector has a good performance. The analysis of the complete signal-cycles allows to get the rising time and pulse heights. The experiment result indicates that cosmic muon and x-ray can be discriminated with an appropriate rising time threshold.

Positron Emission Tomography (PET) using time-of-flight information, which can greatly improve the quality of the reconstructed image, has recently become an exciting topic. In this work, 3.2mm*3.2mm*25mm finger-like LYSO crystals were used to make a 5*5 array, coupled to the Hamamatsu H8500 photomultiplier tube (PMT) as a detector. A fast leading-edge discriminator was designed for the LYSO-H8500 detector. Average coincidence time resolution FWHM of 330 ps was obtained for the LYSO detector with a reference BaF2 detector, whose time resolution for 511 keV {\gamma}-rays was FWHM 150 ps. Time resolution FWHM of 294 ps was calculated for the LYSO detector, and coincidence time resolution of FHWM 415 ps can be expected for two identical LYSO detectors.

Successful phase-matching methods for Third Harmonics Generation (THG) include phase-matching in birefringent crystal and quasi-phase-matching (QPM) in crystal with periodically poled domains. However, these methods are not feasible in some isotropic materials (e.g. fused silica and photosensitive silicate glass). It was known that volume-grating in isotropic materials can independently generate frequency-converted waves. One of disadvantages of single-layer volume-grating is that the brightness of harmonic emission can not be enhanced by increasing the grating thickness. In this paper, a THG device with stratified sub-gratings was designed to enhance THG in isotropic materials: several sub-gratings were arranged parallel, and the grating-figures misalignment between neighboring sub-gratings was pre-fabricated. In terms of extension of interaction length in THG, our multi-layer sub-grating is formally equivalent to the multi-layer periodically poled crystal (e.g. lithium niobate) in conventional QPM approach. According to the calculation results, the N-layer (N >2) can, in principle, generate TH output intensity of N*N times stronger than single-layer volume-grating does, also compared to N times stronger than N-layer without figures-misalignment. The effect of random fabrication error in grating thickness on normalized conversion efficiency was discussed.

In this work we investigate the effects of the littlest Higgs model (LHM) up to the QCD next-to-leading order (NLO) on the $Z^0H^0$ associated production at the CERN Large Hadron Collider (LHC). We study the dependences of the leading order and NLO QCD corrected integrated cross sections for this process on the factorization/renormalization scale and the LHM parameters. We also provide the distributions of the transverse momenta of final decay products $\mu^-$ and $\tau^-$. Our results show that the heavy neutral gauge bosons $Z_H$ and $A_H$ could induce significant discrepancies from the standard model predictions. It is found that when the LHM parameters are taken as $c=0.5$, $c^{\prime}=0.22$, $f=4 TeV$ and $\mu=(M_H+M_Z)/2$, the effects at the $\sqrt{s}=14 TeV$ LHC from the heavy neutral gauge boson are about 12.83% and 10.37% to the leading order and NLO QCD corrected integrated cross sections, respectively. We also conclude that the NLO QCD corrections at the $\sqrt{s}=14 TeV$ LHC can obviously reduce the scale uncertainty of the integrated cross section, and significantly enhance the differential cross sections of $p_T^{\mu^-}$ and $p_T^{\tau^-}$. It demonstrates that the precision measurement of the $Z^0H^0$ associated production process at the LHC could provide the clue of the LHM physics., Comment: 26 pages, 11 figures

We present model calculations of the transport processes of solar energetic particles in the corona and interplanetary medium for two events detected by Parker Solar Probe near its second perihelion on 2019 April 2 and April 4. In the 2019 April 2 event, the <100 keV proton differential intensity measured by the ISOIS EPI-Lo instrument increased by more than a factor of 10 above the pre-event intensity, whereas the ~1 MeV proton differential intensity detected by the EPI-Hi instrument did not show any intensity enhancement. In the 2019 April 4 event, the ~1 MeV proton intensity showed an increase of more than a factor of 100 above the pre-event intensity, but the <100 keV proton intensity enhancement was rather low and gradual. The observational fact that only the 2019 April 4 event displayed a high-energy intensity enhancement indicates that the associated acceleration process in the second event was more energetic than the first event. However, the gradual and low enhancement of the low-energy proton intensity in the second event is at odds with the scenario. In this paper, we investigate the injection and transport processes of protons in the corona and interplanetary magnetic fields with numerical model simulations. Our model calculations suggest that the gradual and low rise of the low-energy protons in the April 4 event was probably due to the different diffusion conditions in these two events and the fact that the spacecraft was moving away from the source region during these two events.