Point-and-Shoot All-in-Focus Photo Synthesis from Smartphone Camera Pair

All-in-Focus (AIF) photography is expected to be a commercial selling point for modern smartphones. Standard AIF synthesis requires manual, time-consuming operations such as focal stack compositing, which is unfriendly to ordinary people. To achieve point-and-shoot AIF photography with a smartphone, we expect that an AIF photo can be generated from one shot of the scene, instead of from multiple photos captured by the same camera. Benefiting from the multi-camera module in modern smartphones, we introduce a new task of AIF synthesis from main (wide) and ultra-wide cameras. The goal is to recover sharp details from defocused regions in the main-camera photo with the help of the ultra-wide-camera one. The camera setting poses new challenges such as parallax-induced occlusions and inconsistent color between cameras. To overcome the challenges, we introduce a predict-and-refine network to mitigate occlusions and propose dynamic frequency-domain alignment for color correction. To enable effective training and evaluation, we also build an AIF dataset with 2686 unique scenes. Each scene includes two photos captured by the main camera, one photo captured by the ultrawide camera, and a synthesized AIF photo. Results show that our solution, termed EasyAIF, can produce high-quality AIF photos and outperforms strong baselines quantitatively and qualitatively. For the first time, we demonstrate point-and-shoot AIF photo synthesis successfully from main and ultra-wide cameras.Comment: Early Access by IEEE Transactions on Circuits and Systems for Video Technology 202

Fast Full-frame Video Stabilization with Iterative Optimization

Video stabilization refers to the problem of transforming a shaky video into a visually pleasing one. The question of how to strike a good trade-off between visual quality and computational speed has remained one of the open challenges in video stabilization. Inspired by the analogy between wobbly frames and jigsaw puzzles, we propose an iterative optimization-based learning approach using synthetic datasets for video stabilization, which consists of two interacting submodules: motion trajectory smoothing and full-frame outpainting. First, we develop a two-level (coarse-to-fine) stabilizing algorithm based on the probabilistic flow field. The confidence map associated with the estimated optical flow is exploited to guide the search for shared regions through backpropagation. Second, we take a divide-and-conquer approach and propose a novel multiframe fusion strategy to render full-frame stabilized views. An important new insight brought about by our iterative optimization approach is that the target video can be interpreted as the fixed point of nonlinear mapping for video stabilization. We formulate video stabilization as a problem of minimizing the amount of jerkiness in motion trajectories, which guarantees convergence with the help of fixed-point theory. Extensive experimental results are reported to demonstrate the superiority of the proposed approach in terms of computational speed and visual quality. The code will be available on GitHub.Comment: Accepted by ICCV202

A Whole Cell Assay to Measure Caspase-6 Activity by Detecting Cleavage of Lamin A/C

Caspase-6 is a cysteinyl protease implicated in neurodegenerative conditions including Alzheimer's and Huntington's disease making it an attractive target for therapeutic intervention. A greater understanding of the role of caspase-6 in disease has been hampered by a lack of suitable cellular assays capable of specifically detecting caspase-6 activity in an intact cell environment. This is mainly due to the use of commercially available peptide substrates and inhibitors which lack the required specificity to facilitate development of this type of assay. We report here a 384-well whole-cell chemiluminescent ELISA assay that monitors the proteolytic degradation of endogenously expressed lamin A/C during the early stages of caspase-dependent apoptosis. The specificity of lamin A/C proteolysis by caspase-6 was demonstrated against recombinant caspase family members and further confirmed in genetic deletion studies. In the assay, plasma membrane integrity remained intact as assessed by release of lactate dehydrogenase from the intracellular environment and the exclusion of cell impermeable peptide inhibitors, despite the induction of an apoptotic state. The method described here is a robust tool to support drug discovery efforts targeting caspase-6 and is the first reported to specifically monitor endogenous caspase-6 activity in a cellular context

Ten-eleven translocation protein 1 modulates medulloblastoma progression

Background: Medulloblastoma (MB) is the most common malignant pediatric brain tumor that originates in the cerebellum and brainstem. Frequent somatic mutations and deregulated expression of epigenetic regulators in MB highlight the substantial role of epigenetic alterations. 5-hydroxymethylcytosine (5hmC) is a highly abundant cytosine modification in the developing cerebellum and is regulated by ten-eleven translocation (TET) enzymes. Results: We investigate the alterations of 5hmC and TET enzymes in MB and their significance to cerebellar cancer formation. We show total abundance of 5hmC is reduced in MB, but identify significant enrichment of MB-specific 5hmC marks at regulatory regions of genes implicated in stem-like properties and Nanog-binding motifs. While TET1 and TET2 levels are high in MBs, only knockout of Tet1 in the smoothened (SmoA1) mouse model attenuates uncontrolled proliferation, leading to a favorable prognosis. The pharmacological Tet1 inhibition reduces cell viability and platelet-derived growth factor signaling pathway-associated genes. Conclusions: These results together suggest a potential key role of 5hmC and indicate an oncogenic nature for TET1 in MB tumorigenesis, suggesting it as a potential therapeutic target for MBs

Assessment of Vulnerability Caused by Earthquake Disasters Based on DEA: A Case Study of County-Level Units in Chinese Mainland

Earthquake activity can generate huge energy in a short period of time, bringing enormous risks to people’s lives and property safety. This poses a great challenge to regional sustainable development. Meanwhile, due to the complex mechanism, seismic activity is difficult to accurately predict. Therefore, it is of great significance to explore how to reduce earthquake disaster losses from the perspective of human society. In this study, we use vulnerability to reflect the relative impact of earthquake disasters on different counties. The vulnerability caused by earthquakes is calculated with the data envelopment analysis (DEA) method. We use CCR and BCC models to further decompose vulnerability into pure technology vulnerability and scale vulnerability. This study analyzes 69 earthquake disasters that occurred in the Chinese mainland from 2013 to 2020 and explores the influencing factors of pure technology vulnerability from both quantitative and qualitative perspectives. Three main conclusions are drawn. First, four factors, including the added value of the secondary industry, gross domestic product (GDP) per capita, investment density of fixed assets and energy released by earthquakes, have a significant impact on the pure technical vulnerability of counties caused by earthquake disasters. Second, in the samples under consideration, the average vulnerability of the regions with an earthquake magnitude below 5.0 is higher than that of the regions with an earthquake magnitude between 5.0 and 6.0. There are deficiencies in organization, management and facilities in regions with a small earthquake risk. Third, through qualitative analysis, it is shown that the seismic function of buildings affects the vulnerability of counties facing earthquake disasters. The results of the research can provide decision makers with new insights into earthquake prevention and disaster reduction management

Synthesis of TiB2/Ti(C,N) cermet by RSPS: formation mechanism, shrinkage behavior, and mechanical properties

TiB2/Ti(C,N) cermet was prepared by reactive spark plasma sintering from the Co-Ti-BN-C-carbide powder compact. The formation mechanism and shrinkage behavior were studied. Results showed that Ti(C,N) was produced by the diffusion of C atoms into a preformed TiN. TiN-forming reaction was exothermic, which would lead to the occurrence of deep macropores and an abnormal expansion phenomenon. With increasing temperature, the macropores became increasingly shallow. Eventually, they disappeared through the viscous flow and dissolution-reaction-precipitation mechanisms. This behavior was primarily responsible for sintering densification. Among various carbide additives, TaC displayed the optimal effect. The hardness and fracture toughness of cermet reached 1917.4 HV and 8.81 MPa m−1/2. The reason was the formation of a black core/gray rim structure by the diffusion of heavy elements in liquid into the Ti(C,N). Results from the present work could offer a deep understanding of reactive spark plasma sintering, and would be beneficial for the development of Ti(C,N)-based cermet

Antibacterial Vancomycin@ZIF-8 Loaded PVA Nanofiber Membrane for Infected Bone Repair

Bone substitutes with strong antibacterial properties and bone regeneration effects have an inherent potential in the treatment of severe bone tissue infections, such as osteomyelitis. In this study, vancomycin (Van) was loaded into zeolitic imidazolate framework-8 (ZIF-8) to prepare composite particles, which is abbreviated as V@Z. As a pH-responsive particle, ZIF-8 can be cleaved in the weak acid environment caused by bacterial infection to realize the effective release of drugs. Then, V@Z was loaded into polyvinyl alcohol (PVA) fiber by electrospinning to prepare PVA/V@Z composite bone filler. The drug-loading rate of V@Z was about 6.735%. The membranes exhibited super hydrophilicity, water absorption and pH-controlled Van release behavior. The properties of anti E. coli and S. aureus were studied under the pH conditions of normal physiological tissues and infected tissues (pH 7.4 and pH 6.5, respectively). It was found that the material had good surface antibacterial adhesion and antibacterial property. The PVA/V@Z membrane had the more prominent bacteria-killing effect compared with the same amount of single antibacterial agent containing membrane such as ZIF-8 or Van loaded PVA, and the antibacterial rate was up to 99%. The electrospun membrane had good biocompatibility and can promote MC3T3-E1 cell spreading on it