•A novel framework is proposed for anomaly detection in videos.•The innovation lies in the combination of prediction and reconstruction methods.•This work is more robust to noise and suitable for ...real-world surveillance videos.•This work outperforms both prediction (baseline) and reconstruction approaches.
Anomaly detection in videos refers to identifying events that rarely or shouldn’t happen in a certain context. Among all existing methods, the idea of reconstruction or future frame prediction is predominant for detecting anomalies. Reconstruction methods try to minimize the reconstruction errors of training data, but cannot guarantee large reconstruction errors for abnormal events. Future frame prediction methods follow the concept that normal events are predictable while abnormal ones are unpredictable. However, the results may drop rapidly since prediction is not robust to the noise in real-world surveillance videos. In this paper, we propose an approach that combines the advantages and balances the disadvantages of these two methods. An end-to-end network is designed to conduct future frame prediction and reconstruction sequentially. Future frame prediction makes the reconstruction errors large enough to facilitate the identification of abnormal events, while reconstruction helps enhance the predicted future frames from normal events. Specifically, we connect two U-Net blocks in the generator. One block works in the form of frame prediction, and the other tries to reconstruct the frames generated by the former block. Experiments over several benchmark datasets demonstrate the superiority of our method over previous state-of-the-art approaches, while running in real-time at 30 frames per second.
An NHC‐catalyzed 3+2 annulations of β‐halocycloenals with isatins upon a dual‐activation mode was developed for the synthesis of tetracyclic 3‐spirooxindoles. DFT calculations were performed for the ...mechanism study of this transformation.
Tetracyclic 3‐spirooxindoles consisted 3,4,5,6‐tetrahydro‐1H‐cyclopentacfuran‐1‐one moieties were synthesized by annulations of β‐halocycloenals with isatins under the catalysis of N‐heterocyclic carbene. DFT calculations were performed for the mechanism study of this reaction.
Non-Markovian spontaneous recovery processes with a time delay (memory) are ubiquitous in the real world. How does the non-Markovian characteristic affect failure propagation in complex networks? We ...consider failures due to internal causes at the nodal level and external failures due to an adverse environment, and develop a pair approximation analysis taking into account the two-node correlation. In general, a high failure stationary state can arise, corresponding to large-scale failures that can significantly compromise the functioning of the network. We uncover a striking phenomenon: memory associated with nodal recovery can counter-intuitively make the network more resilient against large-scale failures. In natural systems, the intrinsic non-Markovian characteristic of nodal recovery may thus be one reason for their resilience. In engineering design, incorporating certain non-Markovian features into the network may be beneficial to equipping it with a strong resilient capability to resist catastrophic failures.
The Cryosphere has been undergoing a worldwide retreat, as seen in the decrease in the areal extent and volume of glaciers and in the areal extent of permafrost. This paper presents a systematic ...examination of the inherent stability changes of glaciers and permafrost caused by warming. Various study results suggest that over the past 30 years, the internal temperature of glaciers and permafrost exhibits an overall accelerating warming trend. The warming rate peaked in the mid-2000s and slowed slightly for several years afterward. In recent years, however, the warming rate has seemed to pick up again. The warming of glaciers and permafrost has exerted great impact on their stability, displayed as intensified melting, increased glacier surging, enlargement of supraglacial lakes, and increased permafrost degradation. Even without a future temperature increase, some glaciers will continue to shrink, and the number of surging glaciers will increase. The transition from low-temperature to high-temperature permafrost is a noticeable warning sign of a comprehensive degradation of permafrost. These results indicate that “warming” glaciers and permafrost will exert significant impacts on the hydrology, ecology, and stability of engineering in cold regions.
Hypertension is regarded as the most prominent risk factor for cardiovascular diseases, which have become a primary cause of death, and recent research has demonstrated that chronic inflammation is ...involved in the pathogenesis of hypertension. Both innate and adaptive immunity are now known to promote the elevation of blood pressure by triggering vascular inflammation and microvascular remodeling. For example, as an important part of innate immune system, classically activated macrophages (M1), neutrophils, and dendritic cells contribute to hypertension by secreting inflammatory cy3tokines. In particular, interferon-gamma (IFN-γ) and interleukin-17 (IL-17) produced by activated T lymphocytes contribute to hypertension by inducing oxidative stress injury and endothelial dysfunction. However, the regulatory T cells and alternatively activated macrophages (M2) may have a protective role in hypertension. Although inflammation is related to hypertension, the exact mechanisms are complex and unclear. The present review aims to reveal the roles of inflammation, immunity, and oxidative stress in the initiation and evolution of hypertension. We envisage that the review will strengthen public understanding of the pathophysiological mechanisms of hypertension and may provide new insights and potential therapeutic strategies for hypertension.
Guest-dependent dynamics having both crystal contraction and expansion upon inclusion of various guests is uncovered in a 3D covalent organic framework (COF) prepared with a facile and scalable ...method. A molecular-level understanding of how the framework adjusts the node geometry and molecular configuration to perform significant contraction and large amplitude expansion are resolved through synchrotron in-house powder X-ray diffraction (PXRD) and Rietveld refinements. We found that the COF adopts a contracted phase at ambient conditions upon capturing moisture and is also adaptive upon inclusion of organic solvents, which is highlighted by a large crystal expansion (as large as 50% crystallographic volume increment and a 3-fold channel size enlargement). With this new knowledge of the structural adaptability, the diverse responses and coherent switchability are thereby presented to pave the way to rational design and deliberate control of dynamic COFs.
•A toe-like structure (TLS) is proposed for low-frequency vibration isolation.•The structure is obtained by imitating toe with nonlinear stiffness and damping.•Adjustable low resonant frequency and ...beneficial damping effect can be obtained.•It provides a feasible way for passive vibration isolation in low frequency band.
Inspired by the cushioning effect of the felid paws in contact with the ground, a novel bio-inspired toe-like structure (TLS) is developed and systematically studied for low-frequency vibration isolation. The TLS consists of two rods with different length (as phalanxes) and a linear spring (as muscle). Based on Hamiltonian principle, the dynamic model is established considering spring deformation and joint rotation damping. The derived equivalent stiffness reveals that the proposed TLS possesses favorable high static and low dynamic stiffness (HSLDS) characteristics in a wide displacement range. Besides, displacement transmissibility suggests that the proposed TLS isolator has low resonance frequency and can effectively isolate base excitation at low frequencies. Comprehensive parameter analysis shows that the inherent nonlinearities in stiffness and damping is conductive to vibration isolation and can be designed/adjusted on demand by selecting suitable structural parameters. This flexibility gives TLS advantages and great potential in extensive engineering applications when subjected to variable vibration loads. A prototype is fabricated and tested for a comprehensive recognize of its advantageous vibration isolation performance in low frequency band. The vibration with excitation frequency higher than 3 Hz can be effectively isolated. This novel bio-inspired TLS provides a feasible approach to passive vibration control and isolation in low frequency band.
Colorectal cancer (CRC) is one of the most common digestive tract tumors worldwide. Catalpol exerts inhibitory effects on the progression of several cancer types by regulating microRNAs (miRs). ...However, the precise role and carcinostatic mechanism of catalpol on CRC cells are poorly understood which limits the application of catalpol treatment. In the present study, miR‑34a and sirtuin 1 (SIRT1) expression levels were detected in CRC tissues and CRC cell lines by RT‑qPCR. Computational software analysis, luciferase assays and western blotting were used to demonstrate the downstream target of miR‑34a in CRC cells. Effects of catalpol on cell viability, apoptosis, autophagic flux and the miR‑34a/SIRT1 axis in the CRC cells were assessed by CCK‑8 assay, flow cytometry, electron microscopy and western blotting, respectively. Whether the miR‑34a/SIRT1 axis participated in catalpol‑mediated autophagy and apoptosis was investigated. The effects of catalpol on the miR‑34a/SIRT1 axis and malignant behavior were evaluated in a rat model of azoxymethane (AOM)‑induced CRC. It was revealed that miR‑34a expression levels were significantly decreased while SIRT1 was overexpressed in most of the CRC tissues and all the CRC cell lines. Clinically, a low level of miR‑34a was correlated with poor clinicopathological characteristics in CRC patients. Catalpol reduced cell viability, suppressed autophagy, promoted apoptosis, and regulated the expression of SIRT1 by inducing miR‑34a in vitro and in vivo. The autophagy‑inhibiting effect of catalpol may be a mechanism to promote apoptosis of CRC cells. miR‑34a mimic transfection resulted in autophagy‑suppressive activity similar to that of catalpol, while the miR‑34a inhibitor attenuated the antiautophagic effects of catalpol. In conclusion, miR‑34a is involved in regulating catalpol‑mediated autophagy and malignant behavior by directly inhibiting SIRT1 in CRC.
Remote photoplethysmography (rPPG) is a non-contact measurement method for estimating heart rate, which has great application potential in medical ward monitoring and remote physiological health ...monitoring. Existing methods for measuring remote physiological signals are susceptible to different degrees of light changes, head movements, and other conditions. In this paper, we design a multi-scale physiological signal feature extraction module (MPSFE) and a plug-and-play time difference global attention module (TDGAM). The MPSFE module extracts different degrees of 3-dimensional convolution of shallow features in the early stage. It obtains more robust semantic information while ensuring the complete position and detailed information to enhance the accuracy and generalization ability of the model. The TDGAM module combines temporal differential convolution with spatial attention and channel attention to enhance the network's localization of the region of interest (ROI) in the case of light changes and head movement. We conduct many experiments on the three datasets, UBFC-rPPG, COHFACE, and PURE. The results shows that our modules significantly improves the accuracy of heart rate measurement.
The mechanism underlying breast cancer stem cell (BCSCs) characteristics remains to be fully elucidated. Accumulating evidence implies that long noncoding RNAs (lncRNAs) play a pivotal role in ...regulating BCSCs stemness.
LncRNA LUCAT1 expression was assessed in breast cancer tissues (n = 151 cases) by in situ hybridization. Sphere-formation assay and colony formation assay were used to detect cell self-renewal and proliferation, respectively. RNA immunoprecipitation, RNA pull down and luciferase reporter assays were used to identify LUCAT1 and TCF7L2 as the direct target of miR-5582-3p. The activity of the Wnt/β-catenin pathway was analyzed by TOP/FOP-Flash reporter assays, western blot and immunohistochemistry (IHC).
This study found LUCAT1 expression was related to tumor size (p = 0.015), lymph node metastasis (p = 0.002) and TNM staging (p < 0.001). High LUCAT1 expression indicated a shorter overall survival (p = 0.006) and disease-free survival (p = 0.011). Furthermore, LUCAT1 was more expressed in BCSCs than in breast cancer cells (BCCs) by lncRNA microarray chips. LUCAT1 up-regulation promoted proliferation of BCCs, while LUCAT1 down-regulation inhibited self-renewal of BCSCs. MiR-5582-3p was directly bound to LUCAT1 and TCF7L2 and negatively regulated their expression. LUCAT1 affected Wnt/β-catenin pathway.
LUCAT1 might be a significant biomarker to evaluate prognosis in breast cancer. LUCAT1 increased stem-like properties of BCCs and stemness of BCSCs by competitively binding miR-5582-3p with TCF7L2 and enhancing the Wnt/β-catenin pathway. The LUCAT1/miR-5582-3p/TCF7L2 axis provides insights for regulatory mechanism of stemness, and new strategies for clinical practice.
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