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1.
Chemistry ; 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34224191

RESUMO

Fluorophores with emission in the second near-infrared window (NIR-II) have displayed salient advantages for biomedical applications. However, to achieve red-shifted wavelengths, the common strategy by reducing the energy bandgap of fluorophores always leads to compromised fluorescent brightness. Herein, we propose a molecular design concept by "ring-fusion" to modify the acceptor of AIEgen, which can extend the luminous wavelength from NIR-I to NIR-II. The yielded fluorophore (TTQP) with fused acceptor has shown enhanced absorption coefficient with a higher brightness in the nanoparticle formation, as compared to its NIR-I emissive counterpart (TTQ-DP) with the non-fused acceptor. Theoretical calculation further confirms that the ring-fusion action can efficiently promote the rigidity and planarity of the electron-deficient core, leading to a lower reorganization energy and nonradiative decay. The yielded TTQP NPs thus allow sensitive NIR-II fluorescence imaging of vasculature and intestinal inflammation in mice models. Therefore, we anticipate that our work will provide a promising molecular engineering strategy to enrich the library and broaden the application scope of NIR-II fluorophores.

2.
Mol Biotechnol ; 2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34302285

RESUMO

Clusters of regularly interspaced short palindromic repeats (CRISPR)/Cas systems have a powerful ability to edit DNA and RNA targets. However, the need for a specific recognition site, protospacer adjacent motif (PAM), of the CRISPR/Cas system limits its application in gene editing. Some Argonaute (Ago) proteins have endonuclease functions under the guidance of 5' phosphorylated or hydroxylated guide DNA (gDNA). The NgAgo protein might perform RNA gene editing at 37 °C, suggesting its application in mammalian cells; however, its mechanisms are unclear. In the present study, the target of NgAgo in RNA was confirmed in vitro and in vivo. Then, an in vitro RNA cleavage system was designed and the cleavage site was verified by sequencing. Furthermore, NgAgo and gDNA were transfected into cells to cleave an intracellular target sequence. We demonstrated targeted degradation of GFP, HCV, and AKR1B10 RNAs in a gDNA-dependent manner by NgAgo both in vitro and in vivo, but no effect on DNA was observed. Sequencing demonstrated that the cleavage sites are located at the 3' of the target RNA which is recognized by 5' sequence of the gDNA. These results confirmed that NgAgo-gDNA cleaves RNA not DNA. We observed that the cleavage site is located at the 3' of the target RNA, which is a new finding that has not been reported in the past.

3.
Cancer Biol Med ; 2021 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-34302324

RESUMO

OBJECTIVE: In the phase II ALTER-1202 (NCT03059797) trial, anlotinib significantly improved progression-free survival (PFS) and overall survival (OS) in patients with advanced small-cell lung cancer (SCLC) who underwent at least 2 previous chemotherapy cycles, when compared with a placebo group. To identify potential factors for predicting efficacy and prognosis with anlotinib treatment, we analyzed hematological indices at baseline and adverse events (AEs) over the course of anlotinib treatment. METHODS: Data were collected from March 2017 to April 2019 from a randomized, double-blind, placebo-controlled, multicenter, phase II trial of anlotinib. Eligible patients were randomly assigned 2:1 to receive anlotinib or placebo until disease progression, intolerable toxicity, or withdrawal of consent. The patients received anlotinib (12 mg) or an analogue capsule (placebo) orally once daily for 14 days every 3 weeks. The hematological indices at baseline and AEs that occurred in the initial 2 treatment cycles were recorded. The Kaplan-Meier test and Cox regression model were used to assess survival differences. RESULTS: A total of 82 patients (81 patients with complete data) were randomly assigned to receive anlotinib, with 38 receiving a placebo as a control. Multivariate analysis indicated that an elevated neutrophil to lymphocyte ratio > 7.75 and lactate dehydrogenase > 254.65 U/L at baseline were independent risk factors for PFS; basal elevated aspartate aminotransferase > 26.75 U/L, neuron specific enolase > 18.64 ng/mL, and fibrinogen > 4.645 g/L were independent risk factors for OS. During treatment, elevated γ glutamyltransferase and hypophosphatemia were independent predictors for a poor PFS, and elevated γ-glutamyl transferase and hypercholesterolemia were independent factors for OS. CONCLUSIONS: Our study preliminarily defined potential factors that affected the PFS and OS at baseline and during anlotinib treatment in patients with advanced SCLC. Our findings provide a basis for screening the dominant population and for dynamic efficacy monitoring with anlotinib therapy.

4.
Int J Cardiol ; 2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34311013

RESUMO

Ischemia/reperfusion (I/R) injury is an inevitable process during heart transplant and suppressing I/R injury could greatly improve the survival rate of recipients. Mesenchymal stem cells (MSCs) have positive effects on I/R. We aimed to investigate the mechanisms underlying the protective roles of MSCs in I/R. Both cell model and rat model of myocardial I/R were used. MTT assay and flow cytometry were used to measure cell viability and apoptosis, respectively. QRT-PCR and western blotting were employed to measure levels of lncRNA HCP5 (HLA complex P5), miR-497, apoptosis-related proteins, and insulin-like growth factor (IGF1)/PI3K/AKT pathway. Dual luciferase assay was used to validate interactions of HCP5 and miR-497, miR-497 and IGF1. Echocardiography was performed to evaluate cardiac function of rats. Serum levels of CK-MB and LDH were measured. H&E and Masson staining were used to examine morphology of myocardial tissues. hBMSC-derived exosomes (hBMSC-Exos) increased the viability of cardiomyocytes following hypoxia/reperfusion (H/R) and decreased apoptosis. H/R diminished HCP5 expression in cardiomyocytes while hBMSC-Exos recovered the level. Overexpression of HCP5 in hBMSC-Exos further enhanced the protective effects in H/R while HCP5 knockdown suppressed. HCP5 directly bound miR-497 and miR-497 targeted IGF1. miR-497 mimics or si-IGF1 blocked the effects of HCP5 overexpression. Further, hBMSC-Exos alleviated I/R injury in vivo and knockdown of HCP5 in hBMSC-Exos decreased the beneficial effects. AntagomiR-497 blocked the effects of HCP5 knockdown. HCP5 from hBMSC-Exos protects cardiomyocytes against I/R injury via sponging miR-497 to disinhibit IGF1/PI3K/AKT pathway. These results shed light on mechanisms underlying the protective role of hBMSC-Exos in I/R.

5.
Adv Healthc Mater ; : e2100569, 2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34313004

RESUMO

The endothelial barrier plays an essential role in health and disease by protecting organs from toxins while allowing nutrients to access the circulation. However, it is the major obstacle that limits the delivery of therapeutic drugs to the diseased tissue. Here, it is reported for the first time that near-infrared (NIR) laser pulses can transiently promote the delivery of semiconducting polymer nanoparticles passing the vascular barrier via photoacoustic-effect-induced accumulation, only by the aid of pulse laser irradiation. This strategy enables selective and substantial accumulation of the NIR-absorbing nanoparticles inside specific tissues, implying the discovery of an unprecedented approach for light-controlled nanoparticle delivery. Especially, the nanoparticle delivery in solid tumors by 10-min laser scanning is approximately six times higher than that of the enhanced permeability and retention (EPR) effect in 24 h under current experimental conditions. Further results confirm that this strategy facilitates substantial accumulation of nanoparticles in the mouse brain with intact skull. This approach thus opens a new door for tissue-specific delivery of nanomaterials with an unprecedented level of efficiency and precision.

6.
Elife ; 102021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34313223

RESUMO

Conserved ATP-dependent chromatin remodelers establish and maintain genome-wide chromatin architectures of regulatory DNA during cellular lifespan, but the temporal interactions between remodelers and chromatin targets have been obscure. We performed live-cell single-molecule tracking for RSC, SWI/SNF, CHD1, ISW1, ISW2, and INO80 remodeling complexes in budding yeast and detected hyperkinetic behaviors for chromatin-bound molecules that frequently transition to the free state for all complexes. Chromatin-bound remodelers display notably higher diffusion than nucleosomal histones, and strikingly fast dissociation kinetics with 4-7 s mean residence times. These enhanced dynamics require ATP binding or hydrolysis by the catalytic ATPase, uncovering an additional function to its established role in nucleosome remodeling. Kinetic simulations show that multiple remodelers can repeatedly occupy the same promoter region on a timescale of minutes, implicating an unending 'tug-of-war' that controls a temporally shifting window of accessibility for the transcription initiation machinery.

7.
Mol Immunol ; 137: 155-162, 2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34252709

RESUMO

Naringenin (Nar) is a flavanone that has been suggested to provide human health benefits such as anti-inflammatory, anti-oxidant and anti-cancer properties. However, the mechanisms underlying these benefits are complex and still not fully understood. In this study, we investigated the effect of Nar on the inflammatory response of macrophages and its underlying mechanism. In lipopolysaccharide (LPS)-stimulated human macrophages, Nar inhibited the activation of NF-κB pathway and suppressed the downstream expression of pro-inflammatory factors. In addition, Nar was also able to induce metallothionein 1 G (MT1G) expression, and the inhibitory effects of Nar on the production of pro-inflammatory cytokines was dependent on MT1G. Mechanistically, we found that MT1G-mediated inhibition of pro-inflammatory cytokines responses might be through repressing NF-κB activation via zinc chelation. Overall, this study reveals a novel mechanism of Nar on inflammatory responses, the suppression of NF-κB activation through upregulation of MT1G.

8.
Int J Mol Sci ; 22(14)2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34299179

RESUMO

The exploitation of new methods to control material structure has historically been dominating the material science. The bottom-up self-assembly strategy by taking atom/molecule/ensembles in nanoscale as building blocks and crystallization as a driving force bring hope for material fabrication. DNA-grafted nanoparticle has emerged as a "programmable atom equivalent" and was employed for the assembly of hierarchically ordered three-dimensional superlattice with novel properties and studying the unknown assembly mechanism due to its programmability and versatility in the binding capabilities. In this review, we highlight the assembly strategies and rules of DNA-grafted three-dimensional superlattice, dynamic assembly by different driving factors, and discuss their future applications.

9.
Proc Natl Acad Sci U S A ; 118(30)2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34301883

RESUMO

Tuberous sclerosis complex 1 (Tsc1) is a tumor suppressor that functions together with Tsc2 to negatively regulate the mechanistic target of rapamycin complex 1 (mTORC1) activity. Here, we show that Tsc1 has a critical role in the tight junction (TJ) formation of epithelium, independent of its role in Tsc2 and mTORC1 regulation. When an epithelial cell establishes contact with neighboring cells, Tsc1, but not Tsc2, migrates from the cytoplasm to junctional membranes, in which it binds myosin 6 to anchor the perijunctional actin cytoskeleton to ß-catenin and ZO-1. In its absence, perijunctional actin cytoskeleton fails to form. In mice, intestine-specific or inducible, whole-body Tsc1 ablation disrupts adherens junction/TJ structures in intestine or skin epithelia, respectively, causing Crohn's disease-like symptoms in the intestine or psoriasis-like phenotypes on the skin. In patients with Crohn's disease or psoriasis, junctional Tsc1 levels in epithelial tissues are markedly reduced, concomitant with the TJ structure impairment, suggesting that Tsc1 deficiency may underlie TJ-related diseases. These findings establish an essential role of Tsc1 in the formation of cell junctions and underpin its association with TJ-related human diseases.

10.
Virus Res ; 302: 198498, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34224768

RESUMO

Infectious bursal disease virus (IBDV), the causative agent of infectious bursal disease (IBD), mainly damages the bursa of Fabricius, which is a central immune organ of birds. As an RNA virus, IBDV is prone to mutation owing to a combination of factors including natural selection pressure. In this study, a naturally occurring mutated IBDV associated with bursa damage was identified, IBDV-HeN20-7103 strain, in an infected chicken flock in central China. Its full-length genome was cloned, and sequence analysis showed that the IBDV-HeN20-7103 strain was located along with the attenuated IBDV, which corresponds to genotype A8B1 of the recently proposed classification scheme, on the branch of the phylogenetic tree. The amino acid sequence comparisons further highlighted the specific characteristics of IBDV-HeN20-7103 with mutation H253Q compared to the attenuated strain. Animal experiments showed that IBDV-HeN20-7103 could induce serious bursal lesions without mortality, which revealed a unique cause of disease in this flock. The identification of such a strain reaffirms the complexity of IBDV evolution and prevalence.

11.
Artigo em Inglês | MEDLINE | ID: mdl-34259984

RESUMO

PURPOSE: Systemic hypertension may induce adverse hypertrophy of the left cardiac ventricle. Pathological cardiac hypertrophy is a common cause of heart failure. We investigated the significance of ferroptosis repressor xCT in hypertrophic cardiomyopathy. METHODS: xCT expression in angiotensin II (Ang II)-treated mouse hearts and rat cardiomyocytes was determined using qRT-PCR and Western blotting. Cardiac hypertrophy was induced by Ang II infusion in xCT knockout mice and their wildtype counterparts. Blood pressure, cardiac pump function, and pathological changes of cardiac remodeling were analyzed in these mice. Cell death, oxidative stress, and xCT-mediated ferroptosis were examined in Ang II-treated rat cardiomyocytes. RESULTS: After Ang II infusion, xCT was downregulated at day 1 but upregulated at day 14 at both mRNA and protein levels. It was also decreased in Ang II-treated cardiomyocytes, but not in cardiofibroblasts. Inhibition of xCT exacerbated cardiomyocyte hypertrophy and boosted the levels of ferroptosis biomarkers Ptgs2, malondialdehyde, and reactive oxygen species induced by Ang II, while overexpression of xCT opposed these detrimental effects. Furthermore, knockout of xCT aggravated Ang II-mediated mouse cardiac fibrosis, hypertrophy, and dysfunction. Ferrostatin-1, a ferroptosis inhibitor, alleviated the exacerbation of cardiomyocyte hypertrophy caused by inhibiting xCT in cultured rat cells or ablating xCT in mice. CONCLUSION: xCT acts as a suppressor in Ang II-mediated cardiac hypertrophy by blocking ferroptosis. Positive modulation of xCT may therefore represent a novel therapeutic approach against cardiac hypertrophic diseases.

12.
Integr Zool ; 2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34254452

RESUMO

Gasterophilus spp. have been found to be widespread in reintroduced Przewalski's horses in the Kalamaili Nature Reserve (Northwest China). However, data on the annual variation in Gasterophilus infections are lacking. To analyze the epidemiological features and determine the cause of the annual variation in Gasterophilus infections, we treated 110 Przewalski's horses with ivermectin and collected Gasterophilus larvae from fecal samples each winter from 2007 to 2019. All 110 Przewalski's horses studied were found to be infected by Gasterophilus spp., and a total of 141,379 larvae were collected. Six species of Gasterophilus were identified with the following prevalence: G. pecorum (100%), G. nasalis (96.36%), G. nigricornis (94.55%), G. haemorrhoidalis (56.36%), G. intestinalis (59.09%), and G. inermis (3.64%). The mean infection intensity of Gasterophilus spp. larvae in Przewalski's horses was 1,285 ± 653. G. pecorum (92.96 ± 6.71%) was the most abundant species. The intensity of Gasterophilus spp. (r = -0.561, p < 0.046) was significantly correlated with winter precipitation. Our findings confirmed that, in the Kalamaili Nature Reserve, gasterophilosis is a severe parasitic disease in Przewalski's horses. Winter precipitation at the beginning of the year can indirectly affect the intensity and composition of Gasterophilus spp. in Przewalski's horses at the end of the year. Therefore, the water-related ecological regulation should be carried out to help reduce the parasite infection of Przewalski's horses. This article is protected by copyright. All rights reserved.

13.
IEEE Trans Cybern ; PP2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34236980

RESUMO

Multiview subspace clustering (MVSC) leverages the complementary information among different views of multiview data and seeks a consensus subspace clustering result better than that using any individual view. Though proved effective in some cases, existing MVSC methods often obtain unsatisfactory results since they perform subspace analysis with raw features that are often of high dimensions and contain noises. To remedy this, we propose a self-guided deep multiview subspace clustering (SDMSC) model that performs joint deep feature embedding and subspace analysis. SDMSC comprehensively explores multiview data and strives to obtain a consensus data affinity relationship agreed by features from not only all views but also all intermediate embedding spaces. With more constraints being cast, the desirable data affinity relationship is supposed to be more reliably recovered. Besides, to secure effective deep feature embedding without label supervision, we propose to use the data affinity relationship obtained with raw features as the supervision signals to self-guide the embedding process. With this strategy, the risk that our deep clustering model being trapped in bad local minima is reduced, bringing us satisfactory clustering results in a higher possibility. The experiments on seven widely used datasets show the proposed method significantly outperforms the state-of-the-art clustering methods. Our code is available at https://github.com/kailigo/dmvsc.git.

14.
Oncogene ; 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34282273

RESUMO

Hepatocellular carcinoma (HCC) is an extremely metastatic tumor. Sialic acids (SAs) are associated with cancer development and metastasis. NEU4 is a sialidase that removes SAs from glycoconjugates, while the function of the NEU4 in HCC has not been clearly explored. In our research, we found the NEU4 expression was significantly down-regulated in HCC tissues, which was correlated with high grades and poor outcomes of HCC. The NEU4 expression could be regulated by histone acetylation. In the functional analysis of NEU4, the cell motility was inhibited when NEU4 was overexpressed, and restored when NEU4 expression was down-regulated. Similarly, NEU4 over-expressed HCC cells showed less metastasis in athymic nude mice. Further study revealed that NEU4 could inhibit cell migration by enzymatic decomposition of SAs. Our results verified a NEU4 active site (NEU4E235) and overexpressing inactivates NEU4E235A that weakens the inhibition ability to cell migration. Further, 70 kinds of specific interacting proteins of NEU4 including CD44 were identified through mass spectrum. Moreover, the α2,3-linked SAs on CD44 were decreased and the hyaluronic acid (HA) binding ability was increased when NEU4 over-expressed or activated. Additionally, the mutation of CD44 with six N-glycosylation sites showed less sensibility to NEU4 on cell migration compared with wild-type CD44. In summary, our results revealed the mechanism of low expression of NEU4 in HCC and its inhibitory effect on cell migration by removal of SAs on CD44, which may provide new treatment strategies to control the motility and metastasis of HCC.

15.
BMJ Open ; 11(7): e047148, 2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34215606

RESUMO

INTRODUCTION: Chronic heart failure (CHF) is a serious and advanced stage of various cardiovascular diseases and portends poor prognosis. An increase in clinical studies has reported the effectiveness of traditional Chinese medicine (TCM). For example, intravenous Chinese medicine can significantly improve cardiac function and biomarkers in patients with CHF. However, there exists inconsistency, lack of practicality and unclear reporting of outcomes in these clinical trials causing difficulty in the comparison of results across similar studies during data synthesis. A core outcome set (COS) can help in the standardisation of outcomes reported across studies from the same healthcare area. The aim of this study is to develop a COS on TCM for CHF (COS-TCM-CHF) to reduce heterogeneity in reporting and improve quality assessment in clinical trials to support data synthesis in addressing the effectiveness of TCM treatment. METHODS AND ANALYSIS: This study will include constructing an outcome pool which will identify potential outcomes through systematic reviews of TCM randomised clinical trials, two clinical registry databases, semi-structured interviews of patients and the clinicians' questionnaire. According to the characteristics of TCM and a taxonomy recommended by the Core Outcome Measures in Effectiveness Trials (COMET) initiative, all outcomes in the outcome pool will be classified into different domains. A preliminary list of outcomes which will then be used in the Delphi survey is generated using a certain criteria based on the length of the pool. The Delphi survey will include two rounds with seven key stakeholder groups to select candidate items for a consensus meeting. A final COS-TCM-CHF will be developed at a face-to-face consensus meeting involving representatives from the different stakeholders. ETHICS AND DISSEMINATION: Ethical approval of this study has been granted by Evidence-based Medicine Centre of Tianjin University of Traditional Chinese Medicine Research Ethics Committee (TJUTCMEC201200002). We will disseminate our research findings of the final COS on the website of Chinese Clinical Trials for Core Outcome Set, with open access publications and present at international conferences to reach a wide range of knowledge users. TRIAL REGISTRATION NUMBER: http://www.comet-initiative.org/studies/details/1486.

16.
Artigo em Inglês | MEDLINE | ID: mdl-34263414

RESUMO

Delayed subglottic stenosis (SGS) is an unusual complication. Here, we report a particular case of delayed SGS. A 17-year-old female suffered extensive injuries including severe neck trauma in a car accident, and complained of dyspnea after 30 days. Tracheal stenosis was observed by fiber optic bronchoscopy, but no specific treatment was administered to the patient. While being transferred to a tertiary hospital 3 days later, the patient fell into deep coma due to hypoxia, and died of hypoxic-ischemic encephalopathy and severe pulmonary infection in the intensive care unit (ICU) 58 days later. Postmortem autopsy and pathological investigation revealed tracheal stenosis 3.0 cm below the vocal cords with a diameter of 0.5 cm, which was caused by a cricoid cartilage fracture, fibrous tissue proliferation and inflammatory cell infiltration. We believed that external forces caused the cricoid fracture and mucosal damage, and after a month of fibrous repair, scar tissue formed the stenosis and caused her death. This report describes a rare condition in which slowly progressive intralaryngeal stenosis formation after external neck trauma could cause asphyxial death in a previously asymptomatic adult.

17.
Carbohydr Polym ; 269: 118248, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34294285

RESUMO

The differences in the source and structure of xylans make them have various biological activities. However, due to their inherent structural limitations, the various biological activities of xylans are far lower than those of commercial drugs. Currently, several types of molecular modification methods have been developed to address these limitations, and many derivatives with specific biological activity have been obtained. Further research on structural characteristics, structure-activity relationship and mechanism of action is of great significance for the development of xylan derivatives. Therefore, the major molecular modification methods of xylans are introduced in this paper, and the primary structure and conformation characteristics of xylans and their derivatives are summarized. In addition, the biological activity and structure-activity relationship of the modified xylans are also discussed.

18.
Mol Plant ; 2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34303025

RESUMO

Soybean mosaic virus (SMV) causes severe yield losses and seed quality reduction in soybean (Glycine max) production worldwide. Rsc4 from cultivar Dabaima is a dominant genetic locus for SMV resistance, and its mapping interval contains three Nucleotide-binding domain Leucine-rich Repeat containing (NLR) candidates (Rsc4-1, Rsc4-2, and Rsc4-3). The NLR-type resistant proteins were considered as important intracellular pathogen sensors in the previous studies. In this research, based on transient expression assay in Nicotiana benthamiana leaves, we found that the longest transcript of Rsc4-3 is sufficient to induce resistance response to SMV; and CRISPR/Cas9-mediated Rsc4-3 knockout in resistant cultivar Dabaima compromised the resistance. These indicate that Rsc4-3 confers resistance to SMV. Interestingly, Rsc4-3 encodes a cell wall localized NLR-type resistant protein (Rsc4-3). The internal polypeptide region responsible for apoplastic targeting of Rsc4-3 and the putative palmitoylation sites on the N-terminus are essential for the resistance response. Furthermore, we showed that viral-encoded cylindrical inclusion (CI) protein partially localizes to the cell wall and can interact with Rsc4-3. Virus-driven or transient expression of CI protein of avirulent SMV strains is enough to induce resistance response in the presence of Rsc4-3, suggesting that CI is the avirulent gene for Rsc4-3 mediated resistance. Our work exhibited a case of NLR recognizing virus in the apoplast and provided a simple and effective method for identifying resistant genes against SMV infection.

19.
Artigo em Inglês | MEDLINE | ID: mdl-34242167

RESUMO

Image denoising is a classical topic yet still a challenging problem, especially for reducing noise from the texture information. Feature scaling (e.g., downscale and upscale) is a widely practice in image denoising to enlarge receptive field size and save resources. However, such a common operation would lose some visual informative details. To address those problems, we propose fast and accurate image denoising via attention guided scaling (AGS). We find that the main informative feature channel and visual primitives during the scaling should keep similar. We then propose to extract the global channel-wise attention to maintain main channel information. Moreover, we propose to collect global descriptors by considering the entire spatial feature. And we then distribute the global descriptors to local positions of the scaled feature, based on their specific needs. We further introduce AGS for adversarial training, resulting in a more powerful discriminator. Extensive experiments show the effectiveness of our proposed method, where we clearly surpass all the state-of-the-art methods on most popular synthetic and real-world denoising benchmarks quantitatively and visually. We further show that our network contributes to other high-level vision applications and improves their performances significantly.

20.
Phys Rev E ; 103(6-1): 063001, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34271621

RESUMO

Controllable wrinkling of dielectric elastomer (DE) sheets is often applied to achieve some special applications such as diffraction gratings, optical sensors, soft actuators, and adjustable wetting surfaces. It is required to precisely predict and control the threshold voltage and wavelength of wrinkling. In view of the weakness of loss of tension criterion, a nonlinear plate theory considering the bending energy of DE sheet is utilized to investigate the wrinkling phenomenon in a prestretched DE sheet with striped electrodes. The results show that the threshold voltage of wrinkling is bigger than the corresponding voltage obtained from loss of tension, which results from the fact that the bending energy has a certain inhibiting effect on wrinkling of the DE sheet. Furthermore, the threshold voltage and wavelength of wrinkling can be effectively regulated by controlling prestretch. The striped electrodes can also effectively control the threshold voltage and wavelength. Especially, there exists an optimal width ratio of electrode corresponding to the lowest threshold voltage. The proposed method can be used to predict and control the behavior of wrinkling in the engineering applications of DE structures.

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