Unified Gas-kinetic Wave-Particle Methods III: Multiscale Photon Transport

In this paper, we extend the unified gas-kinetic wave-particle (UGKWP) method to the multiscale photon transport. In this method, the photon free streaming and scattering processes are treated in an un-splitting way. The duality descriptions, namely the simulation particle and distribution function, are utilized to describe the photon. By accurately recovering the governing equations of the unified gas-kinetic scheme (UGKS), the UGKWP preserves the multiscale dynamics of photon transport from optically thin to optically thick regime. In the optically thin regime, the UGKWP becomes a Monte Carlo type particle tracking method, while in the optically thick regime, the UGKWP becomes a diffusion equation solver. The local photon dynamics of the UGKWP, as well as the proportion of wave-described and particle-described photons are automatically adapted according to the numerical resolution and transport regime. Compared to the $S_n$ -type UGKS, the UGKWP requires less memory cost and does not suffer ray effect. Compared to the implicit Monte Carlo (IMC) method, the statistical noise of UGKWP is greatly reduced and computational efficiency is significantly improved in the optically thick regime. Several numerical examples covering all transport regimes from the optically thin to optically thick are computed to validate the accuracy and efficiency of the UGKWP method. In comparison to the $S_n$ -type UGKS and IMC method, the UGKWP method may have several-order-of-magnitude reduction in computational cost and memory requirement in solving some multsicale transport problems.Comment: 27 pages, 15 figures. arXiv admin note: text overlap with arXiv:1810.0598

Can the Black Lives Matter Movement Reduce Racial Disparities? Evidence from Medical Crowdfunding

Using high-frequency donation records from a major medical crowdfunding site and careful difference-in-difference analysis, we demonstrate that the 2020 BLM surge decreased the fundraising gap between Black and non-Black beneficiaries by around 50\%. The reduction is largely attributed to non-Black donors. Those beneficiaries in counties with moderate BLM activities were most impacted. We construct innovative instrumental variable approaches that utilize weekends and rainfall to identify the global and local effects of BLM protests. Results suggest a broad social movement has a greater influence on charitable-giving behavior than a local event. Social media significantly magnifies the impact of protests

Lack of evidence for involvement of TonEBP and hyperosmotic stimulus in induction of autophagy in the nucleus pulposus.

Nucleus pulposus (NP) cells reside in a physiologically hyperosmotic environment within the intervertebral disc. TonEBP/NFAT5 is an osmo-sensitive transcription factor that controls expression of genes critical for cell survival under hyperosmotic conditions. A recent report on NP and studies of other cell types have shown that hyperosmolarity triggers autophagy. However, little is known whether such autophagy induction occurs through TonEBP. The goal of this study was to investigate the role of TonEBP in hyperosmolarity-dependent autophagy in NP. Loss-of-function studies showed that autophagy in NP cells was not TonEBP-dependent; hyperosmolarity did not upregulate autophagy as previously reported. NP tissue of haploinsufficient TonEBP mice showed normal pattern of LC3 staining. NP cells did not increase LC3-II or LC3-positive puncta under hyperosmotic conditions. Bafilomycin-A1 treatment and tandem mCherry-EGFP-LC3B reporter transfection demonstrated that the autophagic flux was unaffected by hyperosmolarity. Even under serum-free conditions, NP cells did not induce autophagy with increasing osmolarity. Hyperosmolarity did not change the phosphorylation of ULK1 by mTOR and AMPK. An ex vivo disc organ culture study supported that extracellular hyperosmolarity plays no role in promoting autophagy in the NP. We conclude that hyperosmolarity does not play a role in autophagy induction in NP cells

INTERVENTION EFFECT OF SENSORY INTEGRATION TRAINING ON THE BEHAVIORS AND QUALITY OF LIFE OF CHILDREN WITH AUTISM

Background: Autism is a widespread developmental disorder that occurs mostly among children. Children with autism are prone to problematic behaviors due to their deficiencies in language communication and social development. Thus, children with a high degree of autism suffer lower life satisfaction. Moreover, sensory integration dysfunction is closely related to autism. Therefore, the effect of Sensory Integration Training (SIT) on the behaviors and quality of life of children with autism was explored in this study. Subjects and methods: From September 2017 to December 2018, 108 patients from Fuzhou Fourth Hospital and Xiangtan Fifth Hospital were included in the intervention group (group A) and the control group (group B), with 54 members in each group. The 54 members in group B, with an average age of 5.18±2.94, received routine treatment. In addition to the same routine treatment, the members in group B also received sensory integration training and physical exercise intervention, which lasted for three months. The Childhood Autism Rating Scale (CARS) and Autism Behavior Checklist (ABC) were used before and after the intervention experiment to evaluate the curative effect. Results: After the treatment, statistically significant differences were observed in the CARS and ABC scores (P<0.05); the total effective rate was 86.11% in group A and 64.10% in group B. The difference in the CARS score was statistically significant (P<0.05), whereas the difference in the ABC score was also statistically significant (P<0.05). In general, the difference in CARS is statistically significant. Specifically, group A is better than group B, t=3.492, df=73, and bilateral P=0.001<0.01. Conclusions: SIT intervention had a certain effect on autism and is of great value for the future development of SIT courses or intervention programs for children with autism

Efficient Synchronization for GPGPU

High-performance General Purpose Graphics processing units (GPGPUs) have exposed bottlenecks in synchronizations of threads and cores. The massively parallel computing cores and complex hierarchies of threads present new challenges for synchronizations at different granularities. Performance of GPU is hindered by inefficient global and local synchronizations. I propose hardware-software cooperative frameworks for efficient synchronization of GPGPU to address the following issues. To provide efficient global synchronization (Gsync), an API with direct hardware support is proposed. The GPU cores are synchronized by an on-chip Gsync controller. Partial context switch is employed to guarantee deadlock-free execution. The proposed Gsync avoids expensive API calls and alleviates data thrashing. Prioritized warp scheduling is used to increase the overlap of context switch with kernel execution. To efficiently exploit the inherent parallelism of producer-consumer problems, a flexible wait-signal scheme is proposed at thread-block level. I propose dedicated APIs to express fine-grained static and dynamic dependencies with hardware support. The proposed scheme can accelerate wavefront, graph and machine learning applications. The architectural design of on-chip wait-signal controller eliminates busy wait loop and long-latency memory operations. I also propose thread block dispatch scheduling to address the problem of load imbalance and large context switch overhead. To reduce stall due to synchronizations, a synchronization-aware warp scheduling is proposed to coordinate multiple warp schedulers upon synchronization events. Both performance and hardware utilization are improved by resolving the barrier sooner