VideoFlow: Exploiting Temporal Cues for Multi-frame Optical Flow Estimation

We introduce VideoFlow, a novel optical flow estimation framework for videos. In contrast to previous methods that learn to estimate optical flow from two frames, VideoFlow concurrently estimates bi-directional optical flows for multiple frames that are available in videos by sufficiently exploiting temporal cues. We first propose a TRi-frame Optical Flow (TROF) module that estimates bi-directional optical flows for the center frame in a three-frame manner. The information of the frame triplet is iteratively fused onto the center frame. To extend TROF for handling more frames, we further propose a MOtion Propagation (MOP) module that bridges multiple TROFs and propagates motion features between adjacent TROFs. With the iterative flow estimation refinement, the information fused in individual TROFs can be propagated into the whole sequence via MOP. By effectively exploiting video information, VideoFlow presents extraordinary performance, ranking 1st on all public benchmarks. On the Sintel benchmark, VideoFlow achieves 1.649 and 0.991 average end-point-error (AEPE) on the final and clean passes, a 15.1% and 7.6% error reduction from the best-published results (1.943 and 1.073 from FlowFormer++). On the KITTI-2015 benchmark, VideoFlow achieves an F1-all error of 3.65%, a 19.2% error reduction from the best-published result (4.52% from FlowFormer++). Code is released at \url{https://github.com/XiaoyuShi97/VideoFlow}

Development of a New largely scalable in vitro prion propagation method for the production of infectious recombinant prions for high resolution structural studies.

The resolution of the three-dimensional structure of infectious prions at the atomic level is pivotal to understand the pathobiology of Transmissible Spongiform Encephalopathies (TSE), but has been long hindered due to certain particularities of these proteinaceous pathogens. Difficulties related to their purification from brain homogenates of disease-affected animals were resolved almost a decade ago by the development of in vitro recombinant prion propagation systems giving rise to highly infectious recombinant prions. However, lack of knowledge about the molecular mechanisms of the misfolding event and the complexity of systems such as the Protein Misfolding Cyclic Amplification (PMCA), have limited generating the large amounts of homogeneous recombinant prion preparations required for high-resolution techniques such as solid state Nuclear Magnetic Resonance (ssNMR) imaging. Herein, we present a novel recombinant prion propagation system based on PMCA that substitutes sonication with shaking thereby allowing the production of unprecedented amounts of multi-labeled, infectious recombinant prions. The use of specific cofactors, such as dextran sulfate, limit the structural heterogeneity of the in vitro propagated prions and makes possible, for the first time, the generation of infectious and likely homogeneous samples in sufficient quantities for studies with high-resolution structural techniques as demonstrated by the preliminary ssNMR spectrum presented here. Overall, we consider that this new method named Protein Misfolding Shaking Amplification (PMSA), opens new avenues to finally elucidate the three-dimensional structure of infectious prions

In Vitro Amplification of Misfolded Prion Protein Using Lysate of Cultured Cells

Protein misfolding cyclic amplification (PMCA) recapitulates the prion protein (PrP) conversion process under cell-free conditions. PMCA was initially established with brain material and then with further simplified constituents such as partially purified and recombinant PrP. However, availability of brain material from some species or brain material from animals with certain mutations or polymorphisms within the PrP gene is often limited. Moreover, preparation of native PrP from mammalian cells and tissues, as well as recombinant PrP from bacterial cells, involves time-consuming purification steps. To establish a convenient and versatile PMCA procedure unrestricted to the availability of substrate sources, we attempted to conduct PMCA with the lysate of cells that express cellular PrP (PrPC). PrPSc was efficiently amplified with lysate of rabbit kidney epithelial RK13 cells stably transfected with the mouse or Syrian hamster PrP gene. Furthermore, PMCA was also successful with lysate of other established cell lines of neuronal or non-neuronal origins. Together with the data showing that the abundance of PrPC in cell lysate was a critical factor to drive efficient PrPSc amplification, our results demonstrate that cell lysate in which PrPC is present abundantly serves as an excellent substrate source for PMCA

Epigenetic dominance of prion conformers

Although they share certain biological properties with nucleic acid based infectious agents, prions, the causative agents of invariably fatal, transmissible neurodegenerative disorders such as bovine spongiform encephalopathy, sheep scrapie, and human Creutzfeldt Jakob disease, propagate by conformational templating of host encoded proteins. Once thought to be unique to these diseases, this mechanism is now recognized as a ubiquitous means of information transfer in biological systems, including other protein misfolding disorders such as those causing Alzheimer's and Parkinson's diseases. To address the poorly understood mechanism by which host prion protein (PrP) primary structures interact with distinct prion conformations to influence pathogenesis, we produced transgenic (Tg) mice expressing different sheep scrapie susceptibility alleles, varying only at a single amino acid at PrP residue 136. Tg mice expressing ovine PrP with alanine (A) at (OvPrP-A136) infected with SSBP/1 scrapie prions propagated a relatively stable (S) prion conformation, which accumulated as punctate aggregates in the brain, and produced prolonged incubation times. In contrast, Tg mice expressing OvPrP with valine (V) at 136 (OvPrP-V136) infected with the same prions developed disease rapidly, and the converted prion was comprised of an unstable (U), diffusely distributed conformer. Infected Tg mice co-expressing both alleles manifested properties consistent with the U conformer, suggesting a dominant effect resulting from exclusive conversion of OvPrP-V136 but not OvPrP-A136. Surprisingly, however, studies with monoclonal antibody (mAb) PRC5, which discriminates OvPrP-A136 from OvPrP-V136, revealed substantial conversion of OvPrP-A136. Moreover, the resulting OvPrP-A136 prion acquired the characteristics of the U conformer. These results, substantiated by in vitro analyses, indicated that co-expression of OvPrP-V136 altered the conversion potential of OvPrP-A136 from the S to the otherwise unfavorable U conformer. This epigenetic mechanism thus expands the range of selectable conformations that can be adopted by PrP, and therefore the variety of options for strain propagation

Search for a light CP -odd Higgs boson in radiative decays of J /ψ

none406siWe search for a light Higgs boson A0 in the fully reconstructed decay chain of J/ψ→γA0, A0→μ+μ- using (225.0±2.8)×106 J/ψ events collected by the BESIII experiment. The A0 is a hypothetical CP-odd light Higgs boson predicted by many extensions of the Standard Model including two spin-0 doublets plus an extra singlet. We find no evidence for A0 production and set 90% confidence-level upper limits on the product branching fraction B(J/ψ→γA0)×B(A0→μ+μ-) in the range of (2.8-495.3)×10-8 for 0.212≤mA0≤3.0 GeV/c2. The new limits are five times below our previous results, and the nature of the A0 is constrained to be mostly singlet.noneAblikim, M.; Achasov, M.N.; Ai, X.C.; Albayrak, O.; Albrecht, M.; Ambrose, D.J.; Amoroso, A.; An, F.F.; An, Q.; Bai, J.Z.; Baldini Ferroli, R.; Ban, Y.; Bennett, D.W.; Bennett, J.V.; Bertani, M.; Bettoni, D.; Bian, J.M.; Bianchi, F.; Boger, E.; Boyko, I.; Briere, R.A.; Cai, H.; Cai, X.; Cakir, O.; Calcaterra, A.; Cao, G.F.; Cetin, S.A.; Chang, J.F.; Chelkov, G.; Chen, G.; Chen, H.S.; Chen, H.Y.; Chen, J.C.; Chen, M.L.; Chen, S.J.; Chen, X.; Chen, X.R.; Chen, Y.B.; Cheng, H.P.; Chu, X.K.; Cibinetto, G.; Dai, H.L.; Dai, J.P.; Dbeyssi, A.; Dedovich, D.; Deng, Z.Y.; Denig, A.; Denysenko, I.; Destefanis, M.; De Mori, F.; Ding, Y.; Dong, C.; Dong, J.; Dong, L.Y.; Dong, M.Y.; Dou, Z.L.; Du, S.X.; Duan, P.F.; Fan, J.Z.; Fang, J.; Fang, S.S.; Fang, X.; Fang, Y.; Fava, L.; Feldbauer, F.; Felici, G.; Feng, C.Q.; Fioravanti, E.; Fritsch, M.; Fu, C.D.; Gao, Q.; Gao, X.L.; Gao, X.Y.; Gao, Y.; Gao, Z.; Garzia, I.; Goetzen, K.; Gong, W.X.; Gradl, W.; Greco, M.; Gu, M.H.; Gu, Y.T.; Guan, Y.H.; Guo, A.Q.; Guo, L.B.; Guo, Y.; Guo, Y.P.; Haddadi, Z.; Hafner, A.; Han, S.; Harris, F.A.; He, K.L.; Held, T.; Heng, Y.K.; Hou, Z.L.; Hu, C.; Hu, H.M.; Hu, J.F.; Hu, T.; Hu, Y.; Huang, G.M.; Huang, G.S.; Huang, J.S.; Huang, X.T.; Huang, Y.; Hussain, T.; Ji, Q.; Ji, Q.P.; Ji, X.B.; Ji, X.L.; Jiang, L.W.; Jiang, X.S.; Jiang, X.Y.; Jiao, J.B.; Jiao, Z.; Jin, D.P.; Jin, S.; Johansson, T.; Julin, A.; Kalantar-Nayestanaki, N.; Kang, X.L.; Kang, X.S.; Kavatsyuk, M.; Ke, B.C.; Kiese, P.; Kliemt, R.; Kloss, B.; Kolcu, O.B.; Kopf, B.; Kornicer, M.; Kühn, W.; Kupsc, A.; Lange, J.S.; Lara, M.; Larin, P.; Leng, C.; Li, C.; Li, Cheng; Li, D.M.; Li, F.; Li, F.Y.; Li, G.; Li, H.B.; Li, J.C.; Li, Jin; Li, K.; Li, K.; Li, Lei; Li, P.R.; Li, T.; Li, W.D.; Li, W.G.; Li, X.L.; Li, X.M.; Li, X.N.; Li, X.Q.; Li, Z.B.; Liang, H.; Liang, Y.F.; Liang, Y.T.; Liao, G.R.; Lin, D.X.; Liu, B.J.; Liu, C.X.; Liu, D.; Liu, F.H.; Liu, Fang; Liu, Feng; Liu, H.B.; Liu, H.H.; Liu, H.H.; Liu, H.M.; Liu, J.; Liu, J.B.; Liu, J.P.; Liu, J.Y.; Liu, K.; Liu, K.Y.; Liu, L.D.; Liu, P.L.; Liu, Q.; Liu, S.B.; Liu, X.; Liu, Y.B.; Liu, Z.A.; Liu, Zhiqing; Loehner, H.; Lou, X.C.; Lu, H.J.; Lu, J.G.; Lu, Y.; Lu, Y.P.; Luo, C.L.; Luo, M.X.; Luo, T.; Luo, X.L.; Lyu, X.R.; Ma, F.C.; Ma, H.L.; Ma, L.L.; Ma, Q.M.; Ma, T.; Ma, X.N.; Ma, X.Y.; Maas, F.E.; Maggiora, M.; Mao, Y.J.; Mao, Z.P.; Marcello, S.; Messchendorp, J.G.; Min, J.; Mitchell, R.E.; Mo, X.H.; Mo, Y.J.; Morales Morales, C.; Muchnoi, N. Yu.; Muramatsu, H.; Nefedov, Y.; Nerling, F.; Nikolaev, I.B.; Ning, Z.; Nisar, S.; Niu, S.L.; Niu, X.Y.; Olsen, S.L.; Ouyang, Q.; Pacetti, S.; Pan, Y.; Patteri, P.; Pelizaeus, M.; Peng, H.P.; Peters, K.; Pettersson, J.; Ping, J.L.; Ping, R.G.; Poling, R.; Prasad, V.; Qi, M.; Qian, S.; Qiao, C.F.; Qin, L.Q.; Qin, N.; Qin, X.S.; Qin, Z.H.; Qiu, J.F.; Rashid, K.H.; Redmer, C.F.; Ripka, M.; Rong, G.; Rosner, Ch.; Ruan, X.D.; Santoro, V.; Sarantsev, A.; Savrié, M.; Schoenning, K.; Schumann, S.; Shan, W.; Shao, M.; Shen, C.P.; Shen, P.X.; Shen, X.Y.; Sheng, H.Y.; Song, W.M.; Song, X.Y.; Sosio, S.; Spataro, S.; Sun, G.X.; Sun, J.F.; Sun, S.S.; Sun, Y.J.; Sun, Y.Z.; Sun, Z.J.; Sun, Z.T.; Tang, C.J.; Tang, X.; Tapan, I.; Thorndike, E.H.; Tiemens, M.; Ullrich, M.; Uman, I.; Varner, G.S.; Wang, B.; Wang, B.L.; Wang, D.; Wang, D.Y.; Wang, K.; Wang, L.L.; Wang, L.S.; Wang, M.; Wang, P.; Wang, P.L.; Wang, S.G.; Wang, W.; Wang, W.P.; Wang, X.F.; Wang, Y.D.; Wang, Y.F.; Wang, Y.Q.; Wang, Z.; Wang, Z.G.; Wang, Z.H.; Wang, Z.Y.; Weber, T.; Wei, D.H.; Wei, J.B.; Weidenkaff, P.; Wen, S.P.; Wiedner, U.; Wolke, M.; Wu, L.H.; Wu, Z.; Xia, L.; Xia, L.G.; Xia, Y.; Xiao, D.; Xiao, H.; Xiao, Z.J.; Xie, Y.G.; Xiu, Q.L.; Xu, G.F.; Xu, L.; Xu, Q.J.; Xu, X.P.; Yan, L.; Yan, W.B.; Yan, W.C.; Yan, Y.H.; Yang, H.J.; Yang, H.X.; Yang, L.; Yang, Y.; Yang, Y.Y.; Ye, M.; Ye, M.H.; Yin, J.H.; Yu, B.X.; Yu, C.X.; Yu, J.S.; Yuan, C.Z.; Yuan, W.L.; Yuan, Y.; Yuncu, A.; Zafar, A.A.; Zallo, A.; Zeng, Y.; Zeng, Z.; Zhang, B.X.; Zhang, B.Y.; Zhang, C.; Zhang, C.C.; Zhang, D.H.; Zhang, H.H.; Zhang, H.Y.; Zhang, J.J.; Zhang, J.L.; Zhang, J.Q.; Zhang, J.W.; Zhang, J.Y.; Zhang, J.Z.; Zhang, K.; Zhang, L.; Zhang, X.Y.; Zhang, Y.; Zhang, Y.H.; Zhang, Y.N.; Zhang, Y.T.; Zhang, Yu; Zhang, Z.H.; Zhang, Z.P.; Zhang, Z.Y.; Zhao, G.; Zhao, J.W.; Zhao, J.Y.; Zhao, J.Z.; Zhao, Lei; Zhao, Ling; Zhao, M.G.; Zhao, Q.; Zhao, Q.W.; Zhao, S.J.; Zhao, T.C.; Zhao, Y.B.; Zhao, Z.G.; Zhemchugov, A.; Zheng, B.; Zheng, J.P.; Zheng, W.J.; Zheng, Y.H.; Zhong, B.; Zhou, L.; Zhou, X.; Zhou, X.K.; Zhou, X.R.; Zhou, X.Y.; Zhu, K.; Zhu, K.J.; Zhu, S.; Zhu, S.H.; Zhu, X.L.; Zhu, Y.C.; Zhu, Y.S.; Zhu, Z.A.; Zhuang, J.; Zotti, L.; Zou, B.S.; Zou, J.H.Ablikim, M.; Achasov, M. N.; Ai, X. C.; Albayrak, O.; Albrecht, M.; Ambrose, D. J.; Amoroso, A.; An, F. F.; An, Q.; Bai, J. Z.; Baldini Ferroli, R.; Ban, Y.; Bennett, D. W.; Bennett, J. V.; Bertani, M.; Bettoni, D.; Bian, J. M.; Bianchi, F.; Boger, E.; Boyko, I.; Briere, R. A.; Cai, H.; Cai, X.; Cakir, O.; Calcaterra, A.; Cao, G. F.; Cetin, S. A.; Chang, J. F.; Chelkov, G.; Chen, G.; Chen, H. S.; Chen, H. Y.; Chen, J. C.; Chen, M. L.; Chen, S. J.; Chen, X.; Chen, X. R.; Chen, Y. B.; Cheng, H. P.; Chu, X. K.; Cibinetto, G.; Dai, H. L.; Dai, J. P.; Dbeyssi, A.; Dedovich, D.; Deng, Z. Y.; Denig, A.; Denysenko, I.; Destefanis, M.; De Mori, F.; Ding, Y.; Dong, C.; Dong, J.; Dong, L. Y.; Dong, M. Y.; Dou, Z. L.; Du, S. X.; Duan, P. F.; Fan, J. Z.; Fang, J.; Fang, S. S.; Fang, X.; Fang, Y.; Fava, L.; Feldbauer, F.; Felici, G.; Feng, C. Q.; Fioravanti, E.; Fritsch, M.; Fu, C. D.; Gao, Q.; Gao, X. L.; Gao, X. Y.; Gao, Y.; Gao, Z.; Garzia, I.; Goetzen, K.; Gong, W. X.; Gradl, W.; Greco, M.; Gu, M. H.; Gu, Y. T.; Guan, Y. H.; Guo, A. Q.; Guo, L. B.; Guo, Y.; Guo, Y. P.; Haddadi, Z.; Hafner, A.; Han, S.; Harris, F. A.; He, K. L.; Held, T.; Heng, Y. K.; Hou, Z. L.; Hu, C.; Hu, H. M.; Hu, J. F.; Hu, T.; Hu, Y.; Huang, G. M.; Huang, G. S.; Huang, J. S.; Huang, X. T.; Huang, Y.; Hussain, T.; Ji, Q.; Ji, Q. P.; Ji, X. B.; Ji, X. L.; Jiang, L. W.; Jiang, X. S.; Jiang, X. Y.; Jiao, J. B.; Jiao, Z.; Jin, D. P.; Jin, S.; Johansson, T.; Julin, A.; Kalantar Nayestanaki, N.; Kang, X. L.; Kang, X. S.; Kavatsyuk, M.; Ke, B. C.; Kiese, P.; Kliemt, R.; Kloss, B.; Kolcu, O. B.; Kopf, B.; Kornicer, M.; Kühn, W.; Kupsc, A.; Lange, J. S.; Lara, M.; Larin, P.; Leng, C.; Li, C.; Li, Cheng; Li, D. M.; Li, F.; Li, F. Y.; Li, G.; Li, H. B.; Li, J. C.; Li, Jin; Li, K.; Li, K.; Li, Lei; Li, P. R.; Li, T.; Li, W. D.; Li, W. G.; Li, X. L.; Li, X. M.; Li, X. N.; Li, X. Q.; Li, Z. B.; Liang, H.; Liang, Y. F.; Liang, Y. T.; Liao, G. R.; Lin, D. X.; Liu, B. J.; Liu, C. X.; Liu, D.; Liu, F. H.; Liu, Fang; Liu, Feng; Liu, H. B.; Liu, H. H.; Liu, H. H.; Liu, H. M.; Liu, J.; Liu, J. B.; Liu, J. P.; Liu, J. Y.; Liu, K.; Liu, K. Y.; Liu, L. D.; Liu, P. L.; Liu, Q.; Liu, S. B.; Liu, X.; Liu, Y. B.; Liu, Z. A.; Liu, Zhiqing; Loehner, H.; Lou, X. C.; Lu, H. J.; Lu, J. G.; Lu, Y.; Lu, Y. P.; Luo, C. L.; Luo, M. X.; Luo, T.; Luo, X. L.; Lyu, X. R.; Ma, F. C.; Ma, H. L.; Ma, L. L.; Ma, Q. M.; Ma, T.; Ma, X. N.; Ma, X. Y.; Maas, F. E.; Maggiora, M.; Mao, Y. J.; Mao, Z. P.; Marcello, S.; Messchendorp, J. G.; Min, J.; Mitchell, R. E.; Mo, X. H.; Mo, Y. J.; Morales Morales, C.; Muchnoi, N. Y. u.; Muramatsu, H.; Nefedov, Y.; Nerling, F.; Nikolaev, I. B.; Ning, Z.; Nisar, S.; Niu, S. L.; Niu, X. Y.; Olsen, S. L.; Ouyang, Q.; Pacetti, S.; Pan, Y.; Patteri, P.; Pelizaeus, M.; Peng, H. P.; Peters, K.; Pettersson, J.; Ping, J. L.; Ping, R. G.; Poling, R.; Prasad, V.; Qi, M.; Qian, S.; Qiao, C. F.; Qin, L. Q.; Qin, N.; Qin, X. S.; Qin, Z. H.; Qiu, J. F.; Rashid, K. H.; Redmer, C. F.; Ripka, M.; Rong, G.; Rosner, C. h.; Ruan, X. D.; Santoro, V.; Sarantsev, A.; Savrie', Mauro; Schoenning, K.; Schumann, S.; Shan, W.; Shao, M.; Shen, C. P.; Shen, P. X.; Shen, X. Y.; Sheng, H. Y.; Song, W. M.; Song, X. Y.; Sosio, S.; Spataro, S.; Sun, G. X.; Sun, J. F.; Sun, S. S.; Sun, Y. J.; Sun, Y. Z.; Sun, Z. J.; Sun, Z. T.; Tang, C. J.; Tang, X.; Tapan, I.; Thorndike, E. H.; Tiemens, M.; Ullrich, M.; Uman, I.; Varner, G. S.; Wang, B.; Wang, B. L.; Wang, D.; Wang, D. Y.; Wang, K.; Wang, L. L.; Wang, L. S.; Wang, M.; Wang, P.; Wang, P. L.; Wang, S. G.; Wang, W.; Wang, W. P.; Wang, X. F.; Wang, Y. D.; Wang, Y. F.; Wang, Y. Q.; Wang, Z.; Wang, Z. G.; Wang, Z. H.; Wang, Z. Y.; Weber, T.; Wei, D. H.; Wei, J. B.; Weidenkaff, P.; Wen, S. P.; Wiedner, U.; Wolke, M.; Wu, L. H.; Wu, Z.; Xia, L.; Xia, L. G.; Xia, Y.; Xiao, D.; Xiao, H.; Xiao, Z. J.; Xie, Y. G.; Xiu, Q. L.; Xu, G. F.; Xu, L.; Xu, Q. J.; Xu, X. P.; Yan, L.; Yan, W. B.; Yan, W. C.; Yan, Y. H.; Yang, H. J.; Yang, H. X.; Yang, L.; Yang, Y.; Yang, Y. Y.; Ye, M.; Ye, M. H.; Yin, J. H.; Yu, B. X.; Yu, C. X.; Yu, J. S.; Yuan, C. Z.; Yuan, W. L.; Yuan, Y.; Yuncu, A.; Zafar, A. A.; Zallo, A.; Zeng, Y.; Zeng, Z.; Zhang, B. X.; Zhang, B. Y.; Zhang, C.; Zhang, C. C.; Zhang, D. H.; Zhang, H. H.; Zhang, H. Y.; Zhang, J. J.; Zhang, J. L.; Zhang, J. Q.; Zhang, J. W.; Zhang, J. Y.; Zhang, J. Z.; Zhang, K.; Zhang, L.; Zhang, X. Y.; Zhang, Y.; Zhang, Y. H.; Zhang, Y. N.; Zhang, Y. T.; Zhang, Yu; Zhang, Z. H.; Zhang, Z. P.; Zhang, Z. Y.; Zhao, G.; Zhao, J. W.; Zhao, J. Y.; Zhao, J. Z.; Zhao, Lei; Zhao, Ling; Zhao, M. G.; Zhao, Q.; Zhao, Q. W.; Zhao, S. J.; Zhao, T. C.; Zhao, Y. B.; Zhao, Z. G.; Zhemchugov, A.; Zheng, B.; Zheng, J. P.; Zheng, W. J.; Zheng, Y. H.; Zhong, B.; Zhou, L.; Zhou, X.; Zhou, X. K.; Zhou, X. R.; Zhou, X. Y.; Zhu, K.; Zhu, K. J.; Zhu, S.; Zhu, S. H.; Zhu, X. L.; Zhu, Y. C.; Zhu, Y. S.; Zhu, Z. A.; Zhuang, J.; Zotti, L.; Zou, B. S.; Zou, J. H