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The aim of the present study is to quantify the impact that local scale physics of phase change has on the overall heat transfer of the quasi-cubic modular element of an innovative Decay Heat Removal System (DHRS). To evaluate the capabilities of using a solid/liquid phase change material (PCM) to drive passive natural circulation to cool the core of a Sodium-cooled Fast Reactor (SFR), a CFD analysis was carried out using STAR-CCM+. The melting-solidification model that utilizes the Volume- Of-Fluid (VOF) enthalpy-porosity approach proved sufficient when liquid and solid phases are isotropic, homogeneous and remain in thermal equilibrium at the interface, however, demonstrated extreme sensitivity when considering variable density between the phases. A preliminary estimation for the placement of the thermocouples according to the calculations was made for a future experimental study of melting Zamak PCM to measure areas of highly convective motion, hot and cold spots, and the shape of the melting interface

Background and Objective: Several risk factors for the onset of CRPS have been found, but evidence for prognostic factors associated with progression of this condition remains sparse. However, detection and management of these factors are necessary to design secondary prevention strategies. The objective of this systematic review was to identify prognostic factors in adult individuals with early CRPS. Database and Data Treatment: PubMed, Embase, PsycINFO, Cochrane Library, and Scopus, published between Jan 1990 and Nov 2021. Two independent investigators selected cross-sectional and longitudinal studies looking at early (<12 weeks from onset) prognostic factors for pain, CRPS severity score, disability, return to work, or Quality of life. The Quality In Prognostic Studies (QUIPS) tool was used to assess the risk of bias. A qualitative meta-synthesis was performed. Results: Out of 4,652 different articles, six studies met inclusion criteria. We identified 21 early factors associated with poorer prognosis in type I CRPS. We found moderate evidence to support six of them: higher pain intensity, self-rated disability, anxiety, pain-related fear, being a female, and high-energy triggering event. Only two studies had an overall low risk of bias. Conclusions: This study showed an important lack of information on early prognostic factors in CRPS. Only one article investigated the link with psychological characteristics. There is a crucial need of larger studies, with well-defined population using validated measures.

We introduce and describe the 2-category of Grothendieck categories and flat morphisms between them. First, we show that the tensor product of locally presentable linear categories ⊠ restricts nicely to Gr_flat. Then, we characterize exponentiable objects with respect to ⊠: these are the continuous Grothendieck categories. In particular, locally finitely presentable Grothendieck categories are exponentiable. Consequently, we have that, for a quasi-compact quasi-separated scheme X, the category of quasi-coherent sheaves QCoh(X) is exponentiable. Finally, we provide a family of examples and concrete computations of exponentials.

We study fractional variants of the quasi-norms introduced by Brezis, Van Schaftingen, and Yung in the study of the Sobolev space Ẇ1,p. The resulting spaces are identified as a special class of real interpolation spaces of Sobolev-Slobodeckiĭ spaces. We establish the equivalence between Fourier analytic definitions and definitions via difference operators acting on measurable functions. We prove various new results on embeddings and non-embeddings, and give applications to harmonic and caloric extensions. For suitable wavelet bases we obtain a characterization of the approximation spaces for best n-term approximation from a wavelet basis via smoothness conditions on the function; this extends a classical result by DeVore, Jawerth and Popov.

We prove a Tracy-Widom type formula for the generating function of occupancy numbers on several disjoint intervals of the higher order Airy point processes. The formula is related to a new vector-valued Painlevé II hierarchy we define, together with its Lax pair.

Let G be a finite group and U(ZG) the unit group of the integral group ring ZG. We prove a unit theorem, namely a characterization of when U(ZG) satisfies Kazhdan’s property (T), both in terms of the finite group G and in terms of the simple components of the semisimple algebra QG. Furthermore, it is shown that for U(ZG) this property is equivalent to the weaker property FAb (i.e. every subgroup of finite index has finite abelianization), and in particular also to a hereditary version of Serre’s property FA, denoted HFA. More precisely, it is described when all subgroups of finite index in U(ZG) have both finite abelianization and are not a non-trivial amalgamated product. A crucial step for this is a reduction to arithmetic groups SL_n(O), where O is an order in a finite dimensional semisimple Q-algebra D, and finite groups G which have the so-called cut property. For such groups G we describe the simple epimorphic images of QG. The proof of the unit theorem fundamentally relies on fixed point properties and the abelianization of the elementary subgroups En(D) of SL_n(D). These groups are well understood except in the degenerate case of lower rank, i.e. for SL_2(O) with O an order in a division algebra D with a finite number of units. In this setting we determine Serre’s property FA for E_2(O) and its subgroups of finite index. We construct a generic and computable exact sequence describing its abelianization, affording a closed formula for its Z-rank.

Participation at the Workshop "Asymptotics of Quantum Invariants & Volume Conjectures" at the conference "Quantum invariants and low-dimensional topology", San Jose, August 2023.

Using asymptotics of Toeplitz+Hankel determinants, we establish formulae for the asymptotics of the moments of the moments of the characteristic polynomials of random orthogonal and symplectic matrices, as the matrix-size tends to infinity. Our results are analogous to those that Fahs obtained for random unitary matrices in [14]. A key feature of the formulae we derive is that the phase transitions in the moments of moments are seen to depend on the symmetry group in question in a significant way.

It has long been known that in the absence of electric charges and currents, Maxwell's electromagnetism in 4 dimensional vacuum Minkowski space-time is invariant under SO(2) dual transformations that mix its electric and magnetic fields. Extending this symmetry to include the coupling to electrically charged matter, requires a dual coupling to magnetically charged matter as well, leading to Maxwell equations for SO(2) dual electrodynamics. Based on a doubled ensemble of SO(2) dual 4-vector gauge potentials which does away with the need of Dirac string singularities for magnetic monopoles, a local Lagrangian action principle for SO(2) dual electromagnetism is known, which manifestly displays all the required space-time and internal symmetries, and reduces to the experimentally well established Maxwell electrodynamics in the absence of magnetic charges and currents. Applying the same considerations for the matter action of electrically and magnetically charged point particles, a unique SO(2) dual generalised Lorentz force is identified for SO(2) dual electrodynamics, truly different from the usual SO(2) dual invariant choice motivated by simplicity, but yet made arbitrarily and which does not derive from some action principle. This generalised Lorentz force involves a single real and new coupling constant of unknown value, without the requirement of a Dirac-Schwinger-Zwanziger quantisation condition for electric and magnetic charges of dyons. A physical consequence for SO(2) dual electrodynamics of this coupling constant if nonvanishing, is to open a channel, or portal between the otherwise mutually totally ``dark'' sectors of electric and magnetic charges for electromagnetic interactions.

Objective: This study aimed to evaluate the effect of visual feedback, age and movement repetition on the course of upper limb (UL) precision and kinematics. Methods: Fifty-one healthy participants were asked to perform 25 trials of a reaching task in immersive VR with and without benefiting from visual feedback of their hand. They were instructed to place, as accurately as possible, a controller in the centre of a virtual red cube. For each trial, the error distance (distance between the controller and the cube), a coefficient of linearity (CL), the movement time (MT), and the SPARC (a movement smoothness index) were calculated. Correlations and multivariate analyses of variance were conducted to assess the influence of visual feedback, age and movement repetition on the course of the error distance, SPARC, CL and MT throughout the 25 trials. Results: Visual feedback of the hand significantly influenced UL reaching precision (p<0.001), MT (p=0.044) and SPARC (p<0.001) but not CL. The error distance evolvement was significantly influenced by age (p=0.027) and visual feedback (p<0.001); CL by movement repetition (p<0.001) and age (p=0.013); SPARC by movement repetition (p<0.001), visual feedback of the hand (p<0.001) and age (p=0.015); and MT by visual feedback (p=0.001) and movement repetition (p=0.001) but not by age (p=0.671). Conclusion: Results of this study demonstrated that visual feedback of the hand and age have a significant influence on the course of UL precision and movement smoothness in immersive VR.

In view of the observed flat rotation curves of spiral galaxies and motivated by the simple fact that within newtonian gravity a stationary axisymmetric mass distribution or dark matter vortex of finite extent readily displays a somewhat flattened out velocity rotation curve up to distances comparable to the extent of such a vortex transverse to the galaxy's disk, the possibility that such a flattening out of rotation curves may rather be a manifestation of some stationary axisymmetric space-time curvature of purely gravitational character, without the need of some dark matter particles, is considered in the case of the gravimagnetic dipole carrying opposite NUT charges and in the tensionless limit of its Misner string, as an exact vacuum solution to Einstein's equations. Aiming for a first assessment of the potential of such a suggestion easier than a full fledged study of its geodesics, the situation is analysed within the limits of weak field gravito-electromagnetism and nonrelativistic dynamics. Thereby leading indeed to interesting and encouraging results.

Ressources éducatives libres, Open educational resources, Manuel du cours PHQ615 (Université de Sherbrooke). Cette 3ème édition corrige quelques coquilles, introduit quelques nouveaux problèmes (2.8, 3.2, 4.16, 4.17, 4.18, 4.19, 5.4, 5.6, 7.11) et illustrations. Des questions de fin de chapitre ont été ajoutées. Les sections 2.F et 3.B ont été réaménagées. Des remarques importantes ont été ajoutées dans plusieurs autres sections. Contenu: rappels de relativité restreinte; géométrie riemannienne; principes de la relativité générale; géométrie de Schwarzschild; géométrie de Kerr; ondes gravitationnelles; cosmologie., Rappels de relativité restreinte -- Géométrie riemannienne -- Principes fondamentaux de la relativité générale -- Géométrie de Schwarzschild -- Géométrie de Kerr -- Ondes gravitationnelles -- Cosmologie -- Annexes., 3e édition

Objective : Differential diagnosis of persistent migrating hip pain in adolescents is wide. Furthermore, non-traumatic causes of hip pain may be revealed by a traumatic episode. Material / Patients and Methods : We report the case of a 16-year-old boy who developed right hip pain within few days following a bike fall. After one week, he presented to the emergency department with isolated pain at right hip flexion. Conventional radiography was normal. He was discharged with rest and non-steroidal anti-inflammatory drug. A pelvic MRI was performed six week after the fall. It revealed major edema of the femoral head and neck, with heterogeneous enhancement following gadolinium injection. Two weeks later, the patient presented to our consultation with a one-week progressive pain of the left hip. There was no right hip complaint anymore. The patient also reported increased fatigue. Physical examination was normal for the right hip, but revealed a severe, painful, limitation of the flexion and internal rotation of the left hip. Hip ultrasonography and fluoroscopy showed mild left hip effusion. Blood analysis revealed severe hyperleucocytosis, with normal formula. Results : A bone marrow biopsy revealed chronic myeloid leukemia with presence of clonal (9:22) translocation (Philadelphia chromosom). Imatinib, a tyrosine kinase inhibitor, was initiated after complete work-up. Hip pain subsequently disappeared and cytologic remission was rapidly achieved. The child is currently in maintenance therapy. Discussion - Conclusion : This case emphasizes the importance of considering (1) non-traumatic causes of pain in front of atypical post-traumatic pain (2) bone marrow infiltration when facing migrant or persistent inflammatory hip pain.

Fibromyalgia is associated with a premorbid hyperactivity. This study examines how contextual and personality factors contribute to premorbid hyperactivity. A total of 45 patients completed questionnaires. The results show that the number of children and the basic bodily needs neglect (and their interaction) explain nearly 50 percent of the variance of hyperactivity. The neglect toward bodily needs completely mediates the relation between self-oriented perfectionism and hyperactivity. This study suggests that hyperactivity itself would not have a pathological value, but that the neglect of basic bodily needs would represent a vulnerability factor in a hyperactive premorbid lifestyle in fibromyalgia patients.

The fourth catalog of active galactic nuclei (AGNs) detected by the Fermi Gamma-ray Space Telescope Large Area Telescope (4LAC) between 2008 August 4 and 2016 August 2 contains 2863 objects located at high Galactic latitudes (|b| > 10°). It includes 85% more sources than the previous 3LAC catalog based on 4 yr of data. AGNs represent at least 79% of the high-latitude sources in the fourth Fermi-Large Area Telescope Source Catalog (4FGL), which covers the energy range from 50 MeV to 1 TeV. In addition, 344 gamma-ray AGNs are found at low Galactic latitudes. Most of the 4LAC AGNs are blazars (98%), while the remainder are other types of AGNs. The blazar population consists of 24% Flat Spectrum Radio Quasars (FSRQs), 38% BL Lac-type objects, and 38% blazar candidates of unknown types (BCUs). On average, FSRQs display softer spectra and stronger variability in the gamma-ray band than BLQLacs do, confirming previous findings. All AGNs detected by ground-based atmospheric Cerenkov telescopes are also found in the 4LAC.

We report on the observations of gamma-ray burst (GRB) 190114C by the Fermi Gamma-ray Space Telescope and the Neil Gehrels Swift Observatory. The prompt gamma-ray emission was detected by the Fermi GRB Monitor (GBM), the Fermi Large Area Telescope (LAT), and the Swift Burst Alert Telescope (BAT) and the long-lived afterglow emission was subsequently observed by the GBM, LAT, Swift X-ray Telescope (XRT), and Swift UV Optical Telescope. The early-time observations reveal multiple emission components that evolve independently, with a delayed power-law component that exhibits significant spectral attenuation above 40 MeV in the first few seconds of the burst. This power-law component transitions to a harder spectrum that is consistent with the afterglow emission observed by the XRT at later times. This afterglow component is clearly identifiable in the GBM and BAT light curves as a slowly fading emission component on which the rest of the prompt emission is superimposed. As a result, we are able to observe the transition from internal-shock- to external-shock-dominated emission. We find that the temporal and spectral evolution of the broadband afterglow emission can be well modeled as synchrotron emission from a forward shock propagating into a wind-like circumstellar environment. We estimate the initial bulk Lorentz factor using the observed high-energy spectral cutoff. Considering the onset of the afterglow component, we constrain the deceleration radius at which this forward shock begins to radiate in order to estimate the maximum synchrotron energy as a function of time. We find that even in the LAT energy range, there exist high-energy photons that are in tension with the theoretical maximum energy that can be achieved through synchrotron emission from a shock. These violations of the maximum synchrotron energy are further compounded by the detection of very high-energy (VHE) emission above 300 GeV by MAGIC concurrent with our observations. We conclude that the obs

We consider the odd analogue of the category of Soergel bimodules. In the odd case and already for two variables, the transposition bimodule cannot be merged into the generating Soergel bimodule, forcing one into a monoidal category with a larger Grothendieck ring compared to the even case. We establish biadjointness of suitable functors and develop graphical calculi in the 2-variable case for the odd Soergel category and the related singular Soergel 2-category. We describe the odd analogue of the Rouquier complexes and establish their invertibility in the homotopy category. For three variables, the absence of a direct sum decomposition of the tensor product of generating Soergel bimodules presents an obstacle for the Reidemeister III relation to hold in the homotopy category.

We present results of an all-sky search for continuous gravitational waves which can be produced by spinning neutron stars with an asymmetry around their rotation axis, using data from the third observing run of the Advanced LIGO and Advanced Virgo detectors. Four different analysis methods are used to search in a gravitational-wave frequency band from 10 to 2048 Hz and a first frequency derivative from −10−8 to 10−9 Hz/s. No statistically-significant periodic gravitational-wave signal is observed by any of the four searches. As a result, upper limits on the gravitational-wave strain amplitude h0 are calculated. The best upper limits are obtained in the frequency range of 100 to 200 Hz and they are ∼1.1×10−25 at 95\% confidence-level. The minimum upper limit of 1.10×10−25 is achieved at a frequency 111.5 Hz. We also place constraints on the rates and abundances of nearby planetary- and asteroid-mass primordial black holes that could give rise to continuous gravitational-wave signals.

Based on the conservation-dissipation formalism proposed by Zhu and collaborators we formulate a general version of the Israel-Stewart theory for relativistic fluid dynamics with bulk viscosity. Our generalization consists in allowing for a wide range of dependence of the entropy density on the bulk viscosity. We show the existence of Godunov-Boillat variables for this model. By known properties of systems possessing such variables, this provides an alternative proof of the recently established existence of solutions for the Israel-Stewart theory locally in time, and a proof that entropy production is positive across weak Lax shocks.

Background After a stroke, experts recommend regular monitoring and kinematic assessments of patients to objectively measure motor recovery. With the rise of new technologies and increasing needs for neurorehabilitation, an interest in virtual reality has emerged. In this context, we have developed an immersive virtual reality version of the Box and Block Test (BBT-VR). The aim of this study was to assess the concurrent validity of the BBT-VR among patients with stroke and healthy participants. Methods Twenty-three healthy participants and 22 patients with stroke were asked to perform the classical Box and Block Test (BBT) and BBT-VR three times with both hands. Concurrent validity was assessed through correlations between these two tests and reliability of the BBT-VR through correlation on test–retest. Usability of the BBT-VR was also evaluated with the System Usability Scale. Hand kinematic data extracted from controller’s 3D position allowed to compute mean velocity (Vmean), peak velocity (Vpeak) and smoothness (SPARC). Results Results showed strong correlations between the number of blocks displaced with the BBT and the BBT-VR among patients with stroke for affected (r = 0.89; p < 0.001) and less-affected hands (r = 0.76; p < 0.001) and healthy participants for dominant (r = 0.58; p < 0.01) and non-dominant hands (r = 0.68; p < 0.001). Reliability for test–retest was excellent (ICC > 0.8; p < 0.001) and usability almost excellent (System Usability Scale = 79 ± 12.34%). On average participants moved between 30 and 40% less blocks during the BBT-VR than during the BBT. Healthy participants demonstrated significantly higher kinematic measures (Vmean = 0.22 ± 0.086 ms−1; Vpeak = 0.96 ± 0.341 ms−1; SPARC = − 3.31 ± 0.862) than patients with stroke (Vmean = 0.12 ± 0.052 ms−1; Vpeak = 0.60 ± 0.202 ms−1; SPARC = − 5.04[− 7.050 to − 3.682]). Conclusion The BBT-VR is a usable, valid and reliable test to assess manual dexterity, providing kinematic parameters, in a populat

We prove a derived version of the Gabriel–Popescu theorem in the framework of dg-categories and t-structures. This exhibits any pretriangulated dg-category with a suitable t-structure (such that its heart is a Grothendieck abelian category) as a t-exact localization of a derived dg-category of dg-modules. We give an original proof based on a generalization of Mitchell’s argument in "A quick proof of the Gabriel-Popesco theorem" that involves derived injective objects. As an application, we provide a short proof of the fact that derived categories of Grothendieck abelian categories have a unique dg-enhancement.

Lactate dehydrogenases (LDHs) are tetrameric enzymes of therapeutic relevance for cancer therapy due to their important implications in cancer cell metabolism. LDH active site inhibition suffers from different drawbacks due to several features such as high cellular concentration and a shared active site among the dehydrogenase family. Conversely, targeting the LDH oligomeric state is an exciting strategy that could provide a suitable alternative to active-site inhibition. In the present study, we developed a biophysical screening cascade to probe the LDHs tetrameric interface. Using nanoscale differential fluorimetry (nanoDSF) as a primary screening method, we identified a series of hits that destabilize the tetrameric protein. From this primary screening, we validated selected hits using saturation transfer difference nuclear magnetic resonance (STD NMR) and microscale thermophoresis (MST) as a combination of orthogonal biophysical techniques. Finally, we characterized the validated hits and demonstrated that they specifically interact at the tetrameric interface of LDH-1 and LDH-5 and can inhibit the LDH tetramerization process. Overall, this work provides a convenient method for screening ligands at the LDH tetrameric interface and has identified promising hits suitable for further optimization. We believe that this biophysical screening cascade, especially the use of (nano)DSF, could be extended to other homomeric proteins.

Background: The MyotonPro is a portable device for measuring biomechanical and viscoelastic properties in superficial soft tissues. The aims of this study are firstly to validate the MyotonPro compared to a reliable gold-standard frame and secondly to observe the influence of MyotonPro measurement on the total wrist viscoelasticity. Methods: Three silicone polymers with different elastic properties were assessed with the MyotonPro and with a reference rheometer (Universal Tribometer Mod). Then, a free oscillations method was used to measure the passive elastic and viscous stiffness of the wrist and compared to MyotonPro forearm measurements. Results: A one-way ANOVA demonstrated the validity of the MyotonPro's stiffness (p = 0.001), decrement (p < 0.001), and relaxation (p = 0.008) parameters for measuring the elastic stiffness (k) of the three polymers. The MyotonPro parameters demonstrated excellent reliability on the forearm. Proximal and distal anterior myofascial measurements of the MyotonPro were moderately correlated to the elastic stiffness (p = 0.0027–0.0275, absolute r = from 0.270 to 0.375) of the wrist while the postero-distal myofascial tissues of the forearm demonstrated a moderate correlation with the viscous stiffness of the wrist (p = 0.0096–0.0433, absolute r = from 0.257 to 0.326). Discussion: The MyotonPro is a valid device for measuring elastic stiffness as well as a portable, affordable, and easy-to-use tool for quantifying the biomechanical properties and viscoelasticity of myofascial tissue in healthy subjects.

Revue de l’importance de l’activité physique, son impact sur la santé en parallèle aux effets néfastes de la sédentarité, le grand fléau de notre époque. Dans ce contexte s’insère le plan d’action de l’Organisation Mondiale de la Santé pour promouvoir l’activité physique. La présentation couvrira les principaux éléments de ce plan d’action. Finalement, nous sommes intimement liés à la nature à tout point de vue. La présentation passera en revue les dernières évidences sur l’importance de l’activité physique en pleine nature. Chaque élément sera mis sous le prisme du rôle des professionnels de la santé.

The letter reports an observational study, which our group has undertaken, to evaluate the effect of the Covid-19 lockdown among individuals with a spinal cord injury in Belgium. The primary focus of the study was the impact of the lockdown on physical activity levels, as the literature shows that individuals with a physical disability, such as spinal cord injury, particularly benefit from physical activity. The report was written in accordance to the STROBE guidelines.

Only a few data associated to wearability of facemask during exercise are available in children. The aim of the study was to evaluate the effect of wearing a facemask on perceived exertion (primary aim), dyspnea, physical performance, and cardiorespiratory response during a submaximal exercise test in children aged between 8 and 12 years. This study was performed in 2021 in healthy volunteer children from 8 to 12 years. They performed prospectively two 1-min sit-to-stand tests (STST), with or without a surgical facemask. The perceived exertion (modified Borg scale), dyspnea (Dalhousie scale), heart rate, and pulsed oxygen saturation were recorded before and after STST. The STST measured the submaximal performance. Thirty-eight healthy children were recruited (8-9 years: n = 19 and 10-11 years: n = 19). After the STST, the perceived exertion increased with or without a facemask (8-9 years group: + 1 [0.6; 1.4] and + 1.6 [1.0; 2.1] - 10-11 years group: + 1.3 [0.7; 1.8] and + 1.9 [1.3; 2.6]) and it was higher with the facemask. The difference between the two conditions in perceived exertion was not clinically relevant in any group (mBorgf: 0.56 pts and 0.68 pts, respectively). The different domains of dyspnea assessed with Dalhousie scale were not influenced by the facemask. The submaximal performance measured by the STST was not changed by the mask whatever the age group. The cardio-respiratory demand was not clinically modified.Conclusion: The surgical facemask had no impact on dyspnea, cardiorespiratory parameters, and exercise performance during a short submaximal exercise in healthy children.

Most activities of daily life (ADL) require cooperative bimanual movements. A unilateral stroke may severely impair bimanual ADL. How patients with stroke (re)learn to coordinate their upper limbs (ULs) is largely unknown. The objectives are to determine whether patients with chronic supratentorial stroke could achieve bimanual motor skill learning (bim-MSkL) and to compare bim-MSkL between patients and healthy individuals (HIs). Twenty-four patients and ten HIs trained over 3 consecutive days on an asymmetrical bimanual coordination task (CIRCUIT) implemented as a serious game in the REAplan® robot. With a common cursor controlled by coordinated movements of the ULs through robotic handles, they performed as many laps as possible (speed constraint) on the CIRCUIT while keeping the cursor within the track (accuracy constraint). The primary outcome was a bimanual speed/accuracy trade-off (biSAT), we used a bimanual coordination factor (biCO) and bimanual forces (biFOP) for the secondary outcomes. Several clinical scales were used to evaluate motor and cognitive functions. Overall, the patients showed improvements on biSAT and biCO. Based on biSAT progression, the HI achieved a larger bim-MSkL than the patients with mild to moderate impairment (Fugl-Meyer Assessment Upper Extremity (FMA-UE): 28-55, n = 15) but not significantly different from those with minimal motor impairment (FMA-UE: 66, n = 9). There was a significant positive correlation between biSAT evolution and the FMA-UE and Stroke Impact Scale. Both HI and patients with chronic stroke training on a robotic device achieved bim-MSkL, although the more impaired patients were less efficient. Bim-MSkL with REAplan® may be interesting for neurorehabilitation after stroke. ClinicalTrial.gov identifier: NCT03974750. Registered 05 June 2019. https://clinicaltrials.gov/ct2/show/NCT03974750?cond=NCT03974750&draw=2&rank=1.

INTRODUCTION: Ankle arthropathy is highly prevalent among people with haemophilia (PwH), even with prophylaxis, and leads to pain and disability. Mechanisms and consequences of painful symptoms related to ankle arthropathy have not been extensively studied. METHODS: A consecutive sample of 30 adult PwH was included (60 ankles). Ankle structure was assessed with magnetic resonance imaging (IPSG-MRI) and ultrasound (HEAD-US). The HJHS 2.1 assessed function of ankles and knees. Physical functioning was assessed with the Timed Up and Go test, the 2-Minute Walking Test and activity limitations with the HAL questionnaire. Health-related quality of life was evaluated using the EQ-5D-5L questionnaire. Overall pain severity was examined using the Brief Pain Inventory questionnaire and ankle pain intensity with a visual analogue scale. Pressure pain thresholds with an algometer assessed pain sensitivity. Spearman correlations were used to calculate interrelations between joint structure, function and pain. RESULTS: Twenty-five PwH (83%) reported ≥1 painful joint, with 67% reporting the ankle as most painful joint. MRI-confirmed abnormalities were seen in 76% of talocrural and 55% of subtalar joints. HEAD-US abnormalities were seen in 93% of the ankles. A large variation was seen in pain sensitivity at the ankle. While moderate to high correlations were observed between ankle structure and HJHS, no meaningful correlations were found between MRI-scores and pain intensity or sensitivity. CONCLUSIONS: Structural joint damage is present in many ankles but is not related to pain in PwH. Further studies should consider somatosensory nervous system dysfunction in PwH as contributing factor to painful ankle arthropathy.

It is currently unknown whether motor skill learning (MSkL) with the paretic upper limb is possible during the acute phase after stroke and whether lesion localization impacts MSkL. Here, we investigated MSkL in acute (1-7 days post) stroke patients compared with healthy individuals (HIs) and in relation to voxel-based lesion symptom mapping. Twenty patients with acute stroke and 35 HIs were trained over 3 consecutive days on a neurorehabilitation robot measuring speed, accuracy, and movement smoothness variables. Patients used their paretic upper limb and HI used their nondominant upper limb on an MSkL task involving a speed/accuracy trade-off. Generalization was evaluated on day 3. All patients underwent a 3-dimensional magnetic resonance imaging used for VSLM. Most patients achieved MSkL demonstrated by day-to-day retention and generalization of the newly learned skill on day 3. When comparing raw speed/accuracy trade-off values, HI achieved larger MSkL than patients. However, relative speed/accuracy trade-off values showed no significant differences in MSkL between patients and HI on day 3. In patients, MSkL progression correlated with acute motor and cognitive impairments. The voxel-based lesion symptom mapping showed that acute vascular damage to the thalamus or the posterior limb of the internal capsule reduced MSkL. Despite worse motor performance for acute stroke patients compared with HI, most patients were able to achieve MSkL with their paretic upper limb. Damage to the thalamus and posterior limb of the internal capsule, however, reduced MSkL. These data show that MSkL could be implemented into neurorehabilitation during the acute phase of stroke, particularly for patients without lesions to the thalamus and posterior limb of the internal capsule. URL: https://www. gov; Unique identifier: NCT01519843.

Intérêt de la réalité virtuelle dans la rééducation des cérébro-lésés. Quelles évidences ?

Background: To plan treatment and measure patients’ recovery, frequent and time-bounded functional assessments are recommended after a stroke. With the increasing needs for neurorehabilitation, new technological technics such as virtual reality have emerged. To answer these needs, we developed an immersive virtual reality version of the Action Research Arm Test (ARAT-VR). Objective: This study aimed to assess the validity, test-retest reliability and usability of the ARAT-VR among individuals with stroke, healthcare professionals and healthy control subjects (HCS). Methods: Thirty individuals with stroke, ten healthcare professionals and 25 HCS were recruited. Content validity was assessed by asking healthcare professionals to compare the difficulty of the movements performed during the ARAT-VR in comparison to the classical Action Research Arm Test (ARAT). Concurrent validity was measured through correlation between the ARAT-VR and ARAT scores. A third of individuals with stroke and HCS were reseen in a convenient delay to measure test-retest reliability. Usability was measured thanks to the System Usability Scale. Results: On average, healthcare professionals estimated that virtual tasks movements’ difficulty was comparable to those of the classical ARAT expect for the items involving marbles. When assessing paretic hands, strong correlations were found (r = 0.84) between classical ARAT and ARAT-VR scores. Test-retest reliability (ICC = 0.99; p < 0.001) and usability (SUS = 82.5 [75 - 90]) were found to be excellent. Conclusion: The ARAT-VR is a valid, reliable and usable tool holding potential to increase assessment’s frequency and remote evaluation among individuals with stroke.

Serious Game in Stroke Rehabilitation

Introduction: The primary aim of this work was to summarize and compare the effects of active rehabilitation assisted by new technologies (virtual reality (VR), robot-assisted therapy (RAT) and telerehabilitation (TR)) on upper limb motor function and everyday living activity during the subacute and chronic phases of stroke. The secondary aims were to compare the effects of these technologies according to the intervention design (in addition to or in substitution of conventional therapy), the duration of active rehabilitation and the severity of patients' motor impairments. Evidence acquisition: Several databases, namely Pubmed, Scopus, Embase and Cochrane Library, were searched. Studies were included if they were meta-analyses with a moderate to high level of confidence (assessed with AMSTAR-2) that compared the effects of a new technology promoting active rehabilitation to that of a conventional therapy program among patients with stroke. Network meta-analyses were conducted to compare the effects of the new technologies. Evidence synthesis: Eighteen different meta-analyses were selected and fifteen included in the quantitative analysis. In total these 15 meta-analyses were based on 189 different randomized controlled trials. VR (SMD≥0.25; p<0.05), RAT (SMD≥0.29; p≤0.29) and TR (SMD≥-0.08; p≤0.64) were found to be at least as effective as conventional therapy. During the subacute phase, RAT's greatest effect was observed for patients with severe-moderate impairments whereas VR and TR's greatest effects were observed for patients with mild impairments. During the chronic phase, the highest effects were observed for patients with mild impairments, for all studies technologies. Network meta-analyses showed that VR and RAT were both significantly superior to TR in improving motor function during the chronic phase but revealed no significant difference between VR, RAT and TR effectiveness on both motor function (during the subacute phase) and activity (during both chro

Fredholm determinants associated to deformations of the Airy kernel are closely connected to the solution to the Kardar‐Parisi‐Zhang (KPZ) equation with narrow wedge initial data, and they also appear as largest particle distributions in models of positive‐temperature free fermions. We show that logarithmic derivatives of the Fredholm determinants can be expressed in terms of a 2 × 2 Riemann‐Hilbert problem, and we use this to derive asymptotics for the Fredholm determinants. As an application of our result, we derive precise lower tail asymptotics for the solution of the KPZ equation with narrow wedge initial data, refining recent results by Corwin and Ghosal.

In this paper we study handlebody versions of classical diagram algebras, most prominently, handlebody versions of Temperley-Lieb, blob, Brauer/BMW, Hecke and Ariki-Koike algebras. Moreover, motivated by Green-Kazhdan-Lusztig's theory of cells, we reformulate the notion of (sandwich, inflated or affine) cellular algebras. We explain this reformulation and how all of the above algebras are part of this theory.

We consider a general class of exactness properties on a finitely complete category, all of which can be expressed as the condition that a certain morphism in a diagram is a strong epimorphism. For each such exactness property, we characterize finitely bicomplete categories having the property by restricting the condition to those diagrams built from only one object in the category via a left Kan extension. In the regular context, this generalizes the theory of approximate co-operations introduced by D. Bourn and Z. Janelidze. As an application, we deduce from this a characterization of (essentially) algebraic categories satisfying such a given exactness property. The pointed version of these exactness properties is also studied.

We define renormalised energies for maps that describe the first-order asymptotics of harmonic maps outside of singularities arising due to obstructions generated by the boundary data and the mutliple connectedness of the target manifold. The constructions generalise the definition by Bethuel et al. (Ginzburg–Landau vortices, progress in nonlinear differential equations and their applications, vol 13, Birkhäuser, Boston, 1994) for the circle. In general, the singularities are geometrical objects and the dependence on homotopic singularities can be studied through a new notion of synharmony. The renormalised energies are showed to be coercive and Lipschitz-continuous. The renormalised energies are associated to minimising renormalisable singular harmonic maps and minimising configurations of points can be characterised by the flux of the stress–energy tensor at the singularities. We compute the singular energy and the renormalised energy in several particular cases.

We construct a new infinite family of ideal triangulations and H-triangulations for the complements of twist knots, using a method originating from Thurston. These triangulations provide a new upper bound for the Matveev complexity of twist knot complements. We then prove that these ideal triangulations are geometric. The proof uses techniques of Futer and the second author, which consist in studying the volume functional on the polyhedron of angle structures. Finally, we use these triangulations to compute explicitly the partition function of the Teichmüller TQFT and to prove the associated volume conjecture for all twist knots, using the saddle point method.

The mainstay of hemophilia treatment is to prevent bleeding through regular long-term prophylaxis and to control acute breakthrough bleeds. Various treatment options are currently available for prophylaxis, and treatment decision-making is a challenging and multifaceted process of identifying the most appropriate option for each patient. A multidisciplinary expert panel convened to develop a practical, patient-oriented algorithm to facilitate shared treatment decision-making between clinicians and patients. Key variables were identified, and an algorithm proposed based on five variables: bleeding phenotype, musculoskeletal status, treatment adherence, venous access, and lifestyle. A complementary, patient-focused preference tool was also hypothesized, with the aim of exploring individual patients' priorities, preferences, and goals. It is hoped that the proposed algorithm and the hypothesized patient preference tool will assist in selecting a treatment for each patient that is as efficient as possible in preventing bleeds while also accounting for the patient's expectations and priorities.

Upper limb loss alters individuals’ private and professional life. Prosthetic devices are thus a solution to supply the missing upper limb segments. Nevertheless, commercial prostheses are often unaffordable, or inaccessible, to underprivileged individuals (e.g., no health insurance, low incomes, warzone). Among potential affordable alternatives, additive manufacturing, commonly “3D printing”, has been increasingly employed. This technology offers higher availability and accessibility, and can produce complex geometrical and highly customized products, which are essential features for prostheses manufacturing. Therefore, this study aims to portray an overview of reliable open-source upper limb 3D-printed prostheses currently available. We thus searched the scientific literature and online repositories hosting 3D-printable designs. We extracted data relative to mechanical and kinematic properties, 3D printing process and efficacy for each device. We found six studies implementing open-source 3DP upper limb prostheses and twenty-five open-source designs from online databases meeting selection criteria. Devices’ technical specifications were not systematically reported. In conclusion, though open-source 3D-printed upper limb prostheses can perform some functional tasks and grasps, and are widely employed to supply limb differences, further research is mandatory to validate their usage and to prove their clinical efficacy. More guidelines are required to unify contributions from private makers and non-governmental organizations with scientific groups.

First-principle simulations are at the heart of the high-energy physics research program. They link the vast data output of multi-purpose detectors with fundamental theory predictions and interpretation. This review illustrates a wide range of applications of modern machine learning to event generation and simulation-based inference, including conceptional developments driven by the specific requirements of particle physics. New ideas and tools developed at the interface of particle physics and machine learning will improve the speed and precision of forward simulations, handle the complexity of collision data, and enhance inference as an inverse simulation problem. Note: Contribution to Snowmass 2021

We present an algorithm to evaluate multiloop Feynman integrals with an arbitrary number of internal massive lines, with the masses being in general complex-valued, and its implementa- tion in the Mathematica package SeaSyde. The implementation solves by series expansions the system of differential equations satisfied by the Master Integrals. At variance with respect to other existing codes, the analytical continuation of the solution is performed in the complex plane associated to each kinematical invariant. We present the results of the evaluation of the Master Integrals relevant for the NNLO QCD-EW corrections to the neutral-current Drell-Yan processes.

We obtain uniform asymptotics for deformed Airy kernel determinants, which arise in models of finite temperature free fermions and which characterize the narrow wedge solution of the Kardar-Parisi-Zhang equation. The asymptotics for the determinants yield uniform initial data for an associated family of solutions to the Korteweg-de Vries equation, and uniform lower tail asymptotics for the narrow wedge solution of the Kardar-Parisi-Zhang equation.

Interest of virtual reality to assess and rehabilitate motor impairments after stroke