Video compression algorithms are widely used to reduce the huge size of video data, but they also introduce unpleasant visual artifacts due to the lossy compression. In order to improve the quality ...of the compressed videos, we proposed a deep non-local Kalman network for compression artifact reduction. Specifically, the video restoration is modeled as a Kalman filtering procedure and the decoded frames can be restored from the proposed deep Kalman model. Instead of using the noisy previous decoded frames as temporal information, the less noisy previous restored frame is employed in a recursive way, which provides the potential to generate high quality restored frames. In the proposed framework, several deep neural networks are utilized to estimate the corresponding states in the Kalman filter and integrated together in the deep Kalman filtering network. More importantly, we also exploit the non-local prior information by incorporating the spatial and temporal non-local networks for better restoration. Our approach takes the advantages of both the model-based methods and learning-based methods, by combining the recursive nature of the Kalman model and powerful representation ability of neural networks. Extensive experimental results on the Vimeo-90k and HEVC benchmark datasets demonstrate the effectiveness of our proposed method.
Large-scale deep soil desiccation has occurred in the Loess Plateau caused by large-scale introduced vegetation rehabilitation over many years. Consequently, this occurrence has raised concerns among ...scholars regarding the obstacles to plant succession that may result from deep soil desiccation following large-scale artificial vegetation construction. In order to answer the question of whether vegetation can be replanted and water can be restored in the deep dry soil environment in this region, large soil columns in the field were used to simulate dry soil in the 0–1000 cm layer. Some soil columns were planted with Robinia pseudoacacia, Caragana korshinskii, alfalfa (Medicago sativa L.), jujube (Zizyphus jujuba Mill.), and Poa annua, while other columns were covered with stones, branches, ground cloth, and white plastic film. Bare soil columns were used as the control treatment (CK). Dynamic changes of soil water in the 0–1000 cm soil layer of the soil columns were regularly observed, and five years (2014–2018) of continuous observation data were analyzed. The results showed that: (1) Under the condition of severe desiccation of the deep soil layer in the semi-arid loess region of China, reintroducing plants can be successful, and the reintroduced plants can grow normally depending on the amount of local precipitation; (2) Due to the different water consumption amounts of reintroduced plants, a new soil water balance can emerge in the dry soil layer. Plants with high water consumption planted on dry soil can result in more severe soil desiccation, while plants with low water consumption planted on dry soil can alleviate soil desiccation. (3) The use of soil surface mulching had a strong effect on soil water restoration, with the order of effectiveness for soil desiccation remediation being white plastic film > ground cloth > branches ≈ stones > control (CK). In particular, the use of white plastic film can transform severely desiccated soil in the 0–640 cm layer into a non-desiccated state. These research findings directly address long-standing concerns of ecologists regarding plant succession and soil water restoration in deep desiccated soil, and can serve as a reference for the sustainable development of ecological construction in the Loess Plateau of China.
•Large soil columns were used to simulate dry soil in the 0–1000 cm layer (DSL).•Replanting deep-rooted vegetation in the DSL can grow normally, relying on natural precipitation.•The shallow-rooted plants can alleviate the drying status in DSL.•The white plastic film can transform severely desiccated soil into a non-desiccated state.
Video frame interpolation aims to improve users' watching experiences by generating high-frame-rate videos from low-frame-rate ones. Existing approaches typically focus on synthesizing intermediate ...frames using high-quality reference images. However, the captured reference frames may suffer from inevitable spatial degradations such as motion blur, sensor noise, etc. Few studies have approached the joint video enhancement problem, namely synthesizing high-frame-rate and high-quality results from low-frame-rate degraded inputs. In this paper, we propose a unified optimization framework for video frame interpolation with spatial degradations. Specifically, we develop a frame interpolation module with a pyramid structure to cyclically synthesize high-quality intermediate frames. The pyramid module features adjustable spatial receptive field and temporal scope, thus contributing to controllable computational complexity and restoration ability. Besides, we propose an inter-pyramid recurrent module to connect sequential models to exploit the temporal relationship. The pyramid module integrates the recurrent module, thus can iteratively synthesize temporally smooth results. And the pyramid modules share weights across iterations, thus it does not expand the model's parameter size. Our model can be generalized to several applications such as up-converting the frame rate of videos with motion blur, reducing compression artifacts, and jointly super-resolving low-resolution videos. Extensive experimental results demonstrate that our method performs favorably against state-of-the-art methods on various video frame interpolation and enhancement tasks.
Frame rate up conversion (FRUC) can improve the visual quality by interpolating new intermediate frames. However, high frame rate videos by FRUC are confronted with more bitrate consumption or ...annoying artifacts of interpolated frames. In this paper, a novel integration framework of FRUC and high efficiency video coding (HEVC) is proposed based on rate-distortion optimization, and the interpolated frames can be reconstructed at encoder side with low bitrate cost and high visual quality. First, joint motion estimation (JME) algorithm is proposed to obtain robust motion vectors, which are shared between FRUC and video coding. What's more, JME is embedded into the coding loop and employs the original motion search strategy in HEVC coding. Then, the frame interpolation is formulated as a rate-distortion optimization problem, where both the coding bitrate consumption and visual quality are taken into account. Due to the absence of original frames, the distortion model for interpolated frames is established according to the motion vector reliability and coding quantization error. Experimental results demonstrate that the proposed framework can achieve 21% ~ 42% reduction in BDBR, when compared with the traditional methods of FRUC cascaded with coding.
Plants evolved intracellular immune receptors that belong to the NOD-like receptor (NLR) family to recognize the presence of pathogen-derived effector proteins. NLRs possess an N-terminal ...Toll-like/IL-1 receptor (TIR) or a non-TIR domain some of which contain coiled coils (CCs), a central nucleotide-binding (NB-ARC) domain, and a C-terminal leucine-rich repeat (LRR). Activation of NLR proteins results in a rapid and high-amplitude immune response, eventually leading to host cell death at the infection site, the so-called hypersensitive response. Despite their important contribution to immunity, the exact mechanisms of NLR activation and signaling remain unknown and are likely heterogenous. We undertook a detailed structure-function analysis of the plasma membrane (PM)-localized CC NLR Resistance to Pseudomonas syringae pv. maculicola 1 (RPM1) using both stable transgenic Arabidopsis and transient expression in Nicotiana benthamiana. We report that immune signaling is induced only by activated full-length PM-localized RPM1. Our interaction analyses demonstrate the importance of a functional P-loop for in planta interaction of RPM1 with the small host protein RPM1-interacting protein 4 (RIN4), for constitutive preactivation and postactivation self-association of RPM1 and for proper PM localization. Our results reveal an additive effect of hydrophobic conserved residues in the CC domain for RPM1 function and RPM1 self-association and their necessity for RPM1–RIN4 interaction. Thus, our findings considerably extend our understanding of the mechanisms regulating NLR activation at, and signaling from, the PM.
Two diphosphine-protected superatom gold selenido nanoclusters, Au
8
Se
2
(dppm)
4
2+
(SD/Au8a
, dppm = Ph
2
PCH
2
PPh
2
) and Au
8
Se
2
(dppe)
4
2+
(SD/Au8b
, dppe = Ph
2
P(CH
2
)
2
PPh
2
), were ...obtained by the reduction of Au(SMe
2
)Cl in the presence of Ph
3
PSe as the selenium ion releasing agents. Both can be regarded as “superatoms” with 1S
2
configuration based on the spherical Jellium model. Despite the same metal-ligand binding motifs on the surface and the intrinsic
C
2
molecular symmetry, the configurations of Au
8
Se
2
kernels in them are different in terms of Au-Au bonded metallic frameworks.
SD/Au8a
displays a heart-shaped core +
exo
type structure (Au
4
tetrahedron core + two
exo
Au
2
Se units), whereas the two
exo
Au
2
Se counterparts in
SD/Au8b
are additionally locked by an obvious Au-Au bond, forming a distorted hexagonal Au
6
ring with two capping AuSe units appended above and below it. Consequently, they showed different photophysical properties as reflected by their electronic absorption and emission spectra. Especially, both
SD/Au8a
and
SD/Au8b
exhibit blue-shifted thermochromic luminescence upon cooling from 293 to 83 K but the latter exhibits anomalous emission intensity evolution trends due to the occurrence of temperature-induced phase transition as revealed by varied-temperature crystallographic analyses. This work not only clearly illustrates the significance of ligands on tuning the kernel structure but also provides two rarely comparable examples for better understanding of the structure-property relationship of gold nanoclusters.
In order to recognize the different operating conditions of a distributed and complex electromechanical system in the process industry, this work proposed a novel method of condition recognition by ...combining complex network theory with phase space reconstruction. First, a condition-space with complete information was reconstructed based on phase space reconstruction, and each condition in the space was transformed into a node of a complex network. Second, the limited penetrable visibility graph method was applied to establish an undirected and un-weighted complex network for the reconstructed condition-space. Final- ly, the statistical properties of this network were calculated to recognize the different operating conditions. A case study of a real chemical plant was conducted to illustrate the analysis and application processes of the proposed method. The results showed that the method could effectively recognize the different conditions of electromechanical systems. A complex electro- mechanical system can be studied from the systematic and cyber perspectives, and the relationship between the network struc- ture property and the system condition can also be analyzed by utilizing the proposed method.
Intercellular communication in adjacent cell layers determines cell fate and polarity, thus orchestrating tissue specification and differentiation. Here we use the maize stomatal apparatus as a model ...to investigate cell fate determination. Mutations in ZmBZU2 (bizui2, bzu2) confer a complete absence of subsidiary cells (SCs) and normal guard cells (GCs), leading to failure of formation of mature stomatal complexes. Nuclear polarization and actin accumulation at the interface between subsidiary mother cells (SMCs) and guard mother cells (GMCs), an essential pre-requisite for asymmetric cell division, did not occur in Zmbzu2 mutants. ZmBZU2 encodes a basic helix-loop-helix (bHLH) transcription factor, which is an ortholog of AtMUTE in Arabidopsis (BZU2/ZmMUTE). We found that a number of genes implicated in stomatal development are transcriptionally regulated by BZU2/ZmMUTE. In particular, BZU2/ZmMUTE directly binds to the promoters of PAN1 and PAN2, two early regulators of protodermal cell fate and SMC polarization, consistent with the low levels of transcription of these genes observed in bzu2-1 mutants. BZU2/ZmMUTE has the cell-to-cell mobility characteristic similar to that of BdMUTE in Brachypodium distachyon. Unexpectedly, BZU2/ZmMUTE is expressed in GMC from the asymmetric division stage to the GMC division stage, and especially in the SMC establishment stage. Taken together, these data imply that BZU2/ZmMUTE is required for early events in SMC polarization and differentiation as well as for the last symmetrical division of GMCs to produce the two GCs, and is a master determinant of the cell fate of its neighbors through cell-to-cell communication.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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