Publications by authors named "Zhiwen Chen"

158 Publications

Inhibition of SIRT1 Limits Self-Renewal and Oncogenesis by Inducing Senescence of Liver Cancer Stem Cells.

J Hepatocell Carcinoma 2021 29;8:685-699. Epub 2021 Jun 29.

Department of Cell Biology, Center for Stem Cell and Medicine, Second Military Medical University (Navy Medical University), Shanghai, People's Republic of China.

Purpose: Cancer stem cells (CSCs) have been considered involving in tumorigenesis, local recurrence, and therapeutic drug resistance of hepatocellular carcinoma (HCC). To investigate novel and effective methods for targeting hepatic CSCs is crucial for a permanent cure of liver cancer.

Methods: The expression level of SIRT1 was detected in CSCs of HCC tissues and cancer cell lines. Expression of CSC markers, the self-renewal and tumorigenic ability of liver CSCs were analyzed with SIRT1 inhibition. Cellular senescence-related markers were used to detect CSCs senescence after inhibition of SIRT1.

Results: SIRT1 was highly expressed in CSCs of HCC cell lines and human HCC tissues. In vitro study revealed that decreasing of SIRT1 level significantly downregulated the stemness-associated genes of liver CSCs and reduced the CSC stemness properties. Also, downregulated SIRT1 suppressed liver CSCs proliferation by decreasing their self-renewal abilities. Furthermore, CSCs with decreased SIRT1 expression showed limited tumorigenicity and formed smaller HCC tumor in vivo. And SIRT1 decreased CSCs became more susceptible to chemotherapeutic drugs. Mechanistically, SIRT1 decreased CSCs became senescence through the activation of p53-p21 and p16 pathway. The data further indicated that the tumor formed from SIRT1-knockdown CSCs exhibited higher senescence-associated β-galactosidase (SA-β-Gal) activity but lower proliferative capacity.

Conclusion: Taken together, these findings pointed that induction of senescence in liver CSCs is an effective tumor suppression method for HCC, and SIRT1 may be served as a promising target for HCC treatment.
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http://dx.doi.org/10.2147/JHC.S296234DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8254544PMC
June 2021

Assessment of habitat change on bird diversity and bird-habitat network of a Coral Island, South China Sea.

BMC Ecol Evol 2021 Jul 6;21(1):137. Epub 2021 Jul 6.

Institute of Evolution and Ecology, School of Life Sciences, Central China Normal University, Wuhan, 430079, Hubei, China.

Background: Understanding how island ecosystems change across habitats is a major challenge in ecological conservation under the conditions of habitat degradation. According to a 2-year investigation on Dong Island of the Paracel Islands, South China Sea, we assessed the roles of different habitats at the species level and community level of birds using topological and network analysis.

Results: In addition to the thousands of Sula sula (a large-sized arboreal seabird) inhabiting the forests, there were 56 other bird species were recorded, representing 23 families and 12 orders, ranging in habitats of wetlands, forests, shrublands, grasslands, and/or beaches. The bird-habitat network had high nestedness, and bird species showed obvious clustering distribution. Integrated topological and network analysis showed that wetlands had a high contribution to species diversity and network structure, and it was a cluster center of migrant birds. Forests and grasslands were species hub and connector respectively, and forests were also the key habitat for residents. Beaches and shrublands were peripherals. The loss of wetlands and forests will result in a sharp reduction of species richness, and even make the S. sula, and most of the resident birds, become locally extinct.

Conclusions: These results suggest that the wetland and forest habitats on the focal island are key important for migrant birds and resident birds respectively, and therefore much more attention should be paid to conservation of the focal island ecosystems.
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http://dx.doi.org/10.1186/s12862-021-01865-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8259361PMC
July 2021

Efficacy and safety of furosemide for prevention of intradialytic hypotension in haemodialysis patients: protocol for a multicentre randomised controlled trial.

BMJ Open 2021 07 5;11(7):e048015. Epub 2021 Jul 5.

Department of Nephrology, West China Hospital, Sichuan University/ West China School of Nursing, Sichuan University, Chengdu, Sichuan, China.

Introduction: Intradialytic hypotension (IDH) is a frequent and serious complication of maintaining haemodialysis (HD) patients and associated with subsequent cardiovascular events and higher mortality. Furosemide is commonly used in non-dialysis chronic kidney disease patients and can effectively manage the volume and blood pressure. However, these agents are often discontinued on initiation of dialysis. Two large observational studies have demonstrated that furosemide can lower the rate of IDH episodes. However, there is still no randomised controlled trial (RCT) to investigate the efficacy and safety of furosemide for prevention of IDH in HD patients. The purpose of this study was to assess the efficacy of furosemide in reducing IDH in HD patients with residual renal function.

Methods And Analysis: A two-arm, parallel, multicente RCT will be conducted at 12 hospitals in China. An estimated sample of 560 HD patients will be recruited. Eligible patients will be randomly assigned to treatment group (patients receive oral furosemide 80 mg/day; after a 2-week treatment, if their urine volume is less than 400 mL/day, the dose of furosemide is adjusted to 160 mg/day) and blank control group via a central randomisation system using 1:1 ratio. The primary outcome is the occurrence of IDH. Outcome assessors and data analysts will be blinded and participants will be asked not to reveal their allocation to assessors. The outcome analyses will be performed both on the intention-to-treat, which includes all patients randomised, and per-protocol population, which includes eligible patients who adhere to the planned treatment and follow-ups.

Ethics And Dissemination: The trial protocol has been approved by the Biomedical Research Ethics Committee of West China Hospital of Sichuan University (2019.385)Results will be presented at national and international conferences and published in peer-reviewed journals.

Trial Registration Number: ChiCTR2000039724.
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http://dx.doi.org/10.1136/bmjopen-2020-048015DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8258570PMC
July 2021

Hierarchical CoFe LDH/MOF nanorods array with strong coupling effect grown on carbon cloth enables efficient oxidation of water and urea.

Nanotechnology 2021 Jul 2;32(38). Epub 2021 Jul 2.

School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, People's Republic of China.

Oxygen evolution reaction (OER) and urea oxidation reaction (UOR) play important roles in the fields of hydrogen energy production and pollution treatment. Herein, a facile one-step chemical etching strategy is provided for fabricating one-dimensional hierarchical nanorods array composed of CoFe layered double hydroxide (LDH)/metal-organic frameworks (MOFs) supported on carbon cloth as efficient and stable OER and UOR catalysts. By precisely controlling the etching rate, the ligands from Co-MOFs are partially removed, the corresponding metal centers then coordinate with hydroxyl ions to generate ultrathin amorphous CoFe LDH nanosheets. The resultant CoFe LDH/MOFs catalyst possesses large active surface area, enhanced conductivity and extended electron/mass transfer channels, which are beneficial for catalytic reactions. Additionally, the intimate contact between CoFe LDH and MOFs modulates the local electronic structure of the catalytic active site, leading to enhanced adsorption of oxygen-containing intermediates to facilitate fast electrocatalytic reaction. As a result, the optimized CoFe LDH/MOF-0.06 exhibits superior OER activity with a low overpotential of 276 at a current density of 10 mA cmwith long-term durability. Additionally, it merely requires a voltage of 1.45 V to obtain 10 mA cmin 1 M KOH solution with 0.33 urea and is 56 mV lower than the one in pure KOH. The work presented here may hew out a brand-new route to construct multi-functional electrocatalysts for water splitting, COreduction, nitrogen reduction reactions and so on.
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http://dx.doi.org/10.1088/1361-6528/ac0b65DOI Listing
July 2021

Adaptive Linear Span Network for Object Skeleton Detection.

IEEE Trans Image Process 2021 20;30:5096-5108. Epub 2021 May 20.

Conventional networks for object skeleton detection are usually hand-crafted. Despite the effectiveness, hand-crafted network architectures lack the theoretical basis and require intensive prior knowledge to implement representation complementarity for objects/parts in different granularity. In this paper, we propose an adaptive linear span network (AdaLSN), driven by neural architecture search (NAS), to automatically configure and integrate scale-aware features for object skeleton detection. AdaLSN is formulated with the theory of linear span, which provides one of the earliest explanations for multi-scale deep feature fusion. AdaLSN is materialized by defining a mixed unit-pyramid search space, which goes beyond many existing search spaces using unit-level or pyramid-level features. Within the mixed space, we apply genetic architecture search to jointly optimize unit-level operations and pyramid-level connections for adaptive feature space expansion. AdaLSN substantiates its versatility by achieving significantly higher accuracy and latency trade-off compared with the state-of-the-arts. It also demonstrates general applicability to image-to-mask tasks such as edge detection and road extraction. Code is available at https://github.com/sunsmarterjie/SDL-Skeletongithub.com/sunsmarterjie/SDL-Skeleton.
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http://dx.doi.org/10.1109/TIP.2021.3078079DOI Listing
May 2021

Graphene oxide exhibited positive effects on the growth of L.

Physiol Mol Biol Plants 2021 Apr 7;27(4):815-824. Epub 2021 Apr 7.

Institute of Carbon Materials Science, Shanxi Datong University, Datong, 037009 Shanxi Province People's Republic of China.

There is increasing evidence for graphene associated plant growth promotion, however, the chronic effects of soil-applied graphene remain largely unexplored. The present study investigated the morphological, physiological and biochemical responses of graphene oxide (GO) on L. over the concentration range of 0-100 mg/L for four months. Our results demonstrated that GO, with the best efficiency at 50 mg/L, could enhance the photosynthetic capacity of leaves, increase the yield and morphological characters of root and leaf, improve the nutrient (protein and amino acid) contents of leaf, without reducing the content of the main bioactive compound aloin. Compared with leaves, the effect of GO on root growth was more obvious. Although the electrolyte leakage and MDA content were raised at high concentrations, GO treatment did not increase the root antioxidant enzymes activity or decrease the root vigor, which excluding typical stress response. Furthermore, injection experiments showed that the GO in vivo did not change the plant growth state obviously. Taken together, our study revealed the role of GO in promoting growth by stimulating root growth and photosynthesis, which would provide theory basis for GO application in agriculture and forestry.

Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-021-00979-3.
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http://dx.doi.org/10.1007/s12298-021-00979-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8055783PMC
April 2021

A Comparative Study of Deep Neural Network-Aided Canonical Correlation Analysis-Based Process Monitoring and Fault Detection Methods.

IEEE Trans Neural Netw Learn Syst 2021 Apr 22;PP. Epub 2021 Apr 22.

Multivariate analysis is an important kind of method in process monitoring and fault detection, in which the canonical correlation analysis (CCA) makes use of the correlation change between two groups of variables to distinguish the system status and has been greatly studied and applied. For the monitoring of nonlinear dynamic systems, the deep neural network-aided CCA (DNN-CCA) has received much attention recently, but it lacks a general definition and comparative study of different network structures. Therefore, this article first introduces four deep neural network (DNN) models that are suitable to combine with CCA, and the general form of DNN-CCA is given in detail. Then, the experimental comparison of these methods is conducted through three cases, so as to analyze the characteristics and distinctions of CCA aided by each DNN model. Finally, some suggestions on method selection are summarized, and the existed open issues in the current DNN-CCA form and future directions are discussed.
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http://dx.doi.org/10.1109/TNNLS.2021.3072491DOI Listing
April 2021

Analysis of mRNA expression differences in bladder cancer metastasis based on TCGA datasets.

J Int Med Res 2021 Mar;49(3):300060521996929

Department of Urology, the First Affiliated Hospital of the Third Military Medical University, Chongqing, China.

Objective: To investigate the metastatic mechanism of muscle invasive bladder cancer (MIBC), which accounts for approximately 30% of all bladder cancer cases, and is a considerable medical problem with high metastatic and mortality rates.

Methods: The mRNA levels of patients with metastatic MIBC and nonmetastatic MIBC from The Cancer Genome Atlas dataset were compared. An integrated bioinformatics analysis was performed of the differentially expressed genes (DEGs), and analyses of Gene Ontology, Kyoto Encyclopaedia of Genes and Genomes pathway, protein-protein interaction, and survival were performed to investigate differences between metastatic and nonmetastatic MIBC.

Results: Data from 264 patients were included (131 with, and 133 without, metastasis). A total of 385 significantly DEGs were identified, including 209 upregulated genes and 176 downregulated genes. Based on results using the STRING database and the MCODE plugin of Cytoscape software, two clusters were obtained. Moreover, two genes were identified that may be valuable for prognostic analysis: Keratin 38, type I () and Histone cluster 1, H3f ().

Conclusion: The and genes may be important in metastasis of MIBC.
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http://dx.doi.org/10.1177/0300060521996929DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8020247PMC
March 2021

Characterization of cotton ARF factors and the role of GhARF2b in fiber development.

BMC Genomics 2021 Mar 22;22(1):202. Epub 2021 Mar 22.

National Key Laboratory of Plant Molecular Genetics and National Center for Plant Gene Research, Institute of Plant Physiology and Ecology/CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 200032, China.

Background: Cotton fiber is a model system for studying plant cell development. At present, the functions of many transcription factors in cotton fiber development have been elucidated, however, the roles of auxin response factor (ARF) genes in cotton fiber development need be further explored.

Results: Here, we identify auxin response factor (ARF) genes in three cotton species: the tetraploid upland cotton G. hirsutum, which has 73 ARF genes, and its putative extent parental diploids G. arboreum and G. raimondii, which have 36 and 35 ARFs, respectively. Ka and Ks analyses revealed that in G. hirsutum ARF genes have undergone asymmetric evolution in the two subgenomes. The cotton ARFs can be classified into four phylogenetic clades and are actively expressed in young tissues. We demonstrate that GhARF2b, a homolog of the Arabidopsis AtARF2, was preferentially expressed in developing ovules and fibers. Overexpression of GhARF2b by a fiber specific promoter inhibited fiber cell elongation but promoted initiation and, conversely, its downregulation by RNAi resulted in fewer but longer fiber. We show that GhARF2b directly interacts with GhHOX3 and represses the transcriptional activity of GhHOX3 on target genes.

Conclusion: Our results uncover an important role of the ARF factor in modulating cotton fiber development at the early stage.
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http://dx.doi.org/10.1186/s12864-021-07504-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7986310PMC
March 2021

Graph Convolutional Network-Based Method for Fault Diagnosis Using a Hybrid of Measurement and Prior Knowledge.

IEEE Trans Cybern 2021 Mar 12;PP. Epub 2021 Mar 12.

Deep-neural network-based fault diagnosis methods have been widely used according to the state of the art. However, a few of them consider the prior knowledge of the system of interest, which is beneficial for fault diagnosis. To this end, a new fault diagnosis method based on the graph convolutional network (GCN) using a hybrid of the available measurement and the prior knowledge is proposed. Specifically, this method first uses the structural analysis (SA) method to prediagnose the fault and then converts the prediagnosis results into the association graph. Then, the graph and measurements are sent into the GCN model, in which a weight coefficient is introduced to adjust the influence of measurements and the prior knowledge. In this method, the graph structure of GCN is used as a joint point to connect SA based on the model and GCN based on data. In order to verify the effectiveness of the proposed method, an experiment is carried out. The results show that the proposed method, which combines the advantages of both SA and GCN, has better diagnosis results than the existing methods based on common evaluation indicators.
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http://dx.doi.org/10.1109/TCYB.2021.3059002DOI Listing
March 2021

A Single-Side Neural Network-Aided Canonical Correlation Analysis With Applications to Fault Diagnosis.

IEEE Trans Cybern 2021 Mar 11;PP. Epub 2021 Mar 11.

Recently, canonical correlation analysis (CCA) has been explored to address the fault detection (FD) problem for industrial systems. However, most of the CCA-based FD methods assume both Gaussianity of measurement signals and linear relationships among variables. These assumptions may be improper in some practical scenarios so that direct applications of these CCA-based FD strategies are arguably not optimal. With the aid of neural networks, this work proposes a new nonlinear counterpart called a single-side CCA (SsCCA) to enhance FD performance. The contributions of this work are four-fold: 1) an objective function for the nonlinear CCA is first reformulated, based on which a generalized solution is presented; 2) for the practical implementation, a particular solution of SsCCA is developed; 3) an SsCCA-based FD algorithm is designed for nonlinear systems, whose optimal FD ability is illustrated via theoretical analysis; and 4) based on the difference in FD results between two test statistics, fault diagnosis can be directly achieved. The studies on a nonlinear three-tank system are carried out to verify the effectiveness of the proposed SsCCA method.
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http://dx.doi.org/10.1109/TCYB.2021.3060766DOI Listing
March 2021

Synergistic vacancy defects and mechanical strain for the modulation of the mechanical, electronic and optical properties of monolayer tungsten disulfide.

Phys Chem Chem Phys 2021 Mar;23(10):6298-6308

Department of Materials Science and Engineering, University of Toronto, Toronto, ON M5S 3E4, Canada. and Department of Mechanical and Industrial Engineering, University of Toronto, Toronto, ON M5S 3G8, Canada.

Monolayer transition metal dichalcogenides (TMDs) are the potential candidate materials in nanoelectronic and optoelectronic applications due to their unique physical and chemical properties. Although both defect and strain greatly alter the structural, physical and chemical properties of monolayer TMDs, the defective monolayer TMDs under applied strain have not been adequately studied. In this paper, the synergistic effects of sulfur vacancy defects and mechanical strain on the mechanical, electronic and optical properties of monolayer tungsten disulfide (WS2) have been systematically studied using first principles density functional theory. The results indicate that the sulfur vacancy formation energy increases linearly with increasing sulfur vacancy concentration under different strains. The strain energy and stress of monolayer WS2 with different sulfur vacancy concentrations increase with increasing applied strain in the strain range of -10% to 10%. The band gap of monolayer WS2 decreases with increasing sulfur vacancy concentration under different strains. Moreover, compared with unstrained conditions, 5% compressive strain increases the band gap at a larger vacancy concentration and the case is just opposite at a smaller vacancy concentration, while 5% tensile strain decreases the band gap. The band gap of monolayer WS2 with different sulfur vacancy concentrations firstly increases and then shrinks with increasing applied strain under compressive strain, whereas it decreases monotonically under tensile strain in the strain range of -10% to 10%. In the visible-light wavelength region, the out-of-plane absorption coefficient under different strains increases with increasing sulfur vacancy concentration. Furthermore, 5% compressive strain enhances the absorption coefficient and 5% tensile strain decreases the absorption coefficient. Hence, the synergistic effects of sulfur vacancy defects and mechanical strain in monolayer TMDs can open new avenues for their applications in nanoelectronic and optoelectronic devices.
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http://dx.doi.org/10.1039/d0cp06336cDOI Listing
March 2021

Comparative analysis of codon usage between and mitochondrial genomes.

Mitochondrial DNA B Resour 2020 Jun 17;5(3):2500-2506. Epub 2020 Jun 17.

Department of Ecology, Evolution and Organismal Biology, Iowa State University, Ames, IA, USA.

and mitochondrial genomes were analyzed to understand the factors shaping codon usage. While most analyses of codon usage suggest minimal to no bias, nucleotide composition, specifically GC content, was significantly correlated with codon usage. In general, both mitochondrial genomes favor codons that end in A or U, with a secondary preference for pyrimidine rich codons. These observations are similar to previous reports of codon usage in cotton nuclear genomes, possibly suggestive of a general bias spanning genomic compartment. Although evidence for codon usage bias is weak for most genes, we identified six genes (i.e. , , , , and ) with significant nonrandom codon usage. In general, we find multiple factors that influence cotton mitochondrial genome codon usage, which may include selection in a subset of genes.
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http://dx.doi.org/10.1080/23802359.2020.1780969DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7782173PMC
June 2020

How does mass transfer influence electrochemical carbon dioxide reduction reaction? A case study of Ni molecular catalyst supported on carbon.

Chem Commun (Camb) 2021 Feb 13;57(11):1384-1387. Epub 2021 Jan 13.

School of Chemical Engineering, Dalian University of technology, Dalian, 116024, China.

A series of heterogeneous molecular catalysts by immobilizing nickel(ii) phthalocyanine (NiPc) onto different carbon supports were constructed to study the influence of the catalyst's microstructure on the performance of electrochemical carbon dioxide reduction reaction (CORR). The microporous structure of the electrocatalysts could influence CO transfer and therefore change the CO concentration at the surface of the catalyst, which singnificantly impacted the CORR performance.
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http://dx.doi.org/10.1039/d0cc07466gDOI Listing
February 2021

Electroreduction of nitrogen to ammonia on nanoporous gold.

Nanoscale 2021 Jan;13(3):1717-1722

Automobile Materials, Ministry of Education, and School of Materials Science and Engineering, Jilin University, Changchun 130022, China.

The electrochemical reduction of nitrogen (N2) to ammonia (NH3) has attracted attention as an emerging alternative to the traditional Haber-Bosch process to synthesize NH3. Unfortunately, electrocatalytic N2 reduction processes are still very inefficient. Here we report three-dimensional nanoporous gold (NPG) as an efficient and stable electrocatalyst for the N2 reduction reaction at room temperature and atmospheric pressure. NPG can deliver a high NH3 yield rate of 45.7 μg h-1 mg-1cat. and a high faradaic efficiency of 3.41% at an ultralow potential of -0.10 V versus the reversible hydrogen electrode, in 0.1 M HCl solution. These values are much higher than those obtained for most of the reported electrocatalysts under similar experimental conditions. Structural characterization and density functional theory calculations reveal that the excellent electrocatalytic activity of NPG mainly results from the high density of geometrically required surface steps and kinks.
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http://dx.doi.org/10.1039/d0nr07362hDOI Listing
January 2021

Influence of graphene on the multiple metabolic pathways of Zea mays roots based on transcriptome analysis.

PLoS One 2021 4;16(1):e0244856. Epub 2021 Jan 4.

Key Laboratory of National Forest and Grass Administration for the Application of Graphene in Forestry, Institute of Carbon Materials Science, Shanxi Datong University, Datong, P.R. China.

Graphene reportedly exerts positive effects on plant root growth and development, although the corresponding molecular response mechanism remains to be elucidated. Maize seeds were randomly divided into a control and experimental group, and the roots of Zea mays L. seedlings were watered with different concentrations (0-100 mg/L) of graphene to explore the effects and molecular mechanism of graphene on the growth and development of Z. mays L. Upon evaluating root growth indices, 50 mg/L graphene remarkably increased total root length, root volume, and the number of root tips and forks of maize seedlings compared to those of the control group. We observed that the contents of nitrogen and potassium in rhizosphere soil increased following the 50 mg/L graphene treatment. Thereafter, we compared the transcriptome changes in Z. mays roots in response to the 50 mg/L graphene treatment. Transcriptional factor regulation, plant hormone signal transduction, nitrogen and potassium metabolism, as well as secondary metabolism in maize roots subjected to graphene treatment, exhibited significantly upregulated expression, all of which could be related to mechanisms underlying the response to graphene. Based on qPCR validations, we proposed several candidate genes that might have been affected with the graphene treatment of maize roots. The transcriptional profiles presented here provide a foundation for deciphering the mechanism underlying graphene and maize root interaction.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0244856PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7781479PMC
January 2021

A Review of Intelligent Fault Diagnosis for High-Speed Trains: Qualitative Approaches.

Entropy (Basel) 2020 Dec 22;23(1). Epub 2020 Dec 22.

CRRC Changchun Railway Vehicles Co., Ltd., Changchun 130062, China.

For ensuring the safety and reliability of high-speed trains, fault diagnosis (FD) technique plays an important role. Benefiting from the rapid developments of artificial intelligence, intelligent FD (IFD) strategies have obtained much attention in the field of academics and applications, where the qualitative approach is an important branch. Therefore, this survey will present a comprehensive review of these qualitative approaches from both theoretical and practical aspects. The primary task of this paper is to review the current development of these qualitative IFD techniques and then to present some of the latest results. Another major focus of our research is to introduce the background of high-speed trains, like the composition of the core subsystems, system structure, etc., based on which it becomes convenient for researchers to extract the diagnostic knowledge of high-speed trains, where the purpose is to understand how to use these types of knowledge. By reasonable utilization of the knowledge, it is hopeful to address various challenges caused by the coupling among subsystems of high-speed trains. Furthermore, future research trends for qualitative IFD approaches are also presented.
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http://dx.doi.org/10.3390/e23010001DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7822053PMC
December 2020

Deletion of pksA attenuates the melanogenesis, growth and sporulation ability and causes increased sensitivity to stress response and antifungal drugs in the human pathogenic fungus Fonsecaea monophora.

Microbiol Res 2021 Mar 5;244:126668. Epub 2020 Dec 5.

Department of Dermatology and Venerology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China; Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China. Electronic address:

Fonsecaea monophora, which is very similar to Fonsecaea pedrosoi in morphological features, has been commonly misdiagnosed as F. pedrosoi. Like F. pedrosoi, F. monophora has been also identified as a predominant pathogen of Chromoblastomycosis (CBM). Melanin has been recognized as a virulence factor in several fungi, however, it is still largely unknown about the biological role of melanin and how melanin is synthesized in F. monophora. In this study, we identified two putative polyketide synthase genes (pks), AYO21_03016 (pksA) and AYO21_10638, by searching against the genome of F. monophora. AYO21_03016 and AYO21_10638 were further targeted disrupted by Agrobacterium tumefaciens-mediated transformation (ATMT). We discovered that pksA gene was the major polyketide synthase required for melanin synthesis in F. monophora, rather than AYO21_10638. Phenotypic analysis showed that, knocking out of the pksA gene attenuated melanogenesis, growth rate, sporulation ability and virulence of F. monophora, as compared with wild-type and complementation strain (pksA-C). Furthermore, the ΔpksA mutant was confirmed to be more sensitive to the oxidative stress, extreme pH environment, and antifungal drugs including itraconazole (ITC), terbinafine (TER), and amphotericin B (AMB). Taken together, these findings enabled us to comprehend the role of pksA in regulating DHN-melanin pathway and its effect on the biological function of F. monophora.
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http://dx.doi.org/10.1016/j.micres.2020.126668DOI Listing
March 2021

Round ligament suspending treatment in orthotopic ileal-neobladder after radical cystectomy in women: a single-centre prospective randomised trial.

BJU Int 2021 Aug 11;128(2):187-195. Epub 2020 Dec 11.

Department of Urology, Urology Institute of PLA, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China.

Objectives: To compare the occurrence of emptying dysfunction between surgical techniques for orthotopic neobladder suspended with round ligament (rONB) and the standard procedure (sONB).

Patients And Methods: A prospective randomised controlled trial was performed in a single centre of female patients undergoing creation of an ONB using rONB or sONB. Patients were followed for ≥24 months after ONB. The primary endpoints were significant post-void residual urine volume (sPVR) and need for clean intermittent catheterisation (CIC) at 24 months postoperatively. The secondary endpoints included early and late complications, urodynamic profile, and ONB continence.

Results: Between January 2011 and October 2017, the trial enrolled 85 patients, of whom 82 were randomised. A total of 41 patients had a rONB and 41 a sONB. At 24 months, 17 of the 37 patients with a sONB and nine of the 39 patients with a rONB had a sPVR. The cumulative risk of a sPVR was significantly lower in the rONB group (23.1%) vs the sONB group (45.9%) (hazard ratio [HR] 0.43, 95% confidence interval [CI], 0.19-0.96; P = 0.040). In all, 15 of the 37 patients with a sONB and four of the 39 patients with a rONB needed CIC. The cumulative risk of requiring CIC was significantly lower in the rONB group (10.3%) vs the sONB group (40.5%) (HR 0.22, 95% CI 0.07-0.67; P = 0.008) at 24 months. Multivariable Cox regression analysis also showed that the rONB type was an independently protective factor for sPVR and CIC. The rates of early (0-90 days) and late complication (>90 days) were 54.1% and 13.5% in the sONB group, and 64.1% and 10.3% in the rONB group, respectively. There were no significant differences in complications, urodynamic profile or ONB continence. A major limitation is the small sample size at a single centre.

Conclusion: Posterior support with round ligament for an ONB significantly improved the emptying of the ONB and resulted in a reduced need for CIC. The surgical modification is a feasible and safe technique without additional complication-related surgeries.
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http://dx.doi.org/10.1111/bju.15306DOI Listing
August 2021

Transition metal-N embedded black phosphorus carbide as a high-performance bifunctional electrocatalyst for ORR/OER.

Nanoscale 2020 Sep 8;12(36):18721-18732. Epub 2020 Sep 8.

Department of Materials Science and Engineering, University of Toronto, Toronto, Ontario M5S 3E4, Canada.. and Department of Mechanical and Industrial Engineering, University of Toronto, Toronto, Ontario M5S 3G8, Canada.

Designing highly active electrocatalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is an important challenge in energy conversion and storage technology. In this work, based on computational screening over doping of 23 kinds of transition metals (TMs), we use first-principles study to explore the ORR and OER activity of TM-N embedded black phosphorus carbide monolayer (b-PC). The results show that its catalytic performance highly depends on the number of electrons in the d orbital and the number of valence electrons of introduced TM atom. Moreover, we found that Co-N-bPC (η = 0.31 V; η = 0.22 V), Rh-N-bPC (η = 0.33 V; η = 0.62 V), and Ir-N-bPC (η = 0.21 V; η = 0.21 V) can be promising candidates as bifunctional catalysts for both the ORR and OER and can be comparable or superior to TM-N-graphene in terms of overpotential. They experience no structural distortion at 500 K. Moreover, the exfoliation energy of b-PC is lower than that of graphene, and these three promising candidates show much lower formation energy than TM-N-graphene. Our study provides a systematical method for designing and developing high performance 2D material-based single atom catalysts (SACs) beyond graphene.
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http://dx.doi.org/10.1039/d0nr03339aDOI Listing
September 2020

Survival after radical cystectomy for bladder cancer: Multicenter comparison between minimally invasive and open approaches.

Asian J Urol 2020 Jul 14;7(3):291-300. Epub 2020 Jun 14.

Department of Urology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China.

Objective: To investigate oncological outcomes in patients with bladder cancer who underwent minimally invasive radical cystectomy (MIRC) or open radical cystectomy (ORC).

Methods: We identified patients with bladder cancer who underwent radical cystectomy (RC) in 13 centers of the Chinese Bladder Cancer Consortium (CBCC). Perioperative outcomes were compared between MIRC and ORC. The influence of surgical approaches on overall survival (OS) and cancer-specific survival (CSS) in the entire study group and subgroups classified according to pathologic stage or lymph node (LN) status was assessed with the log-rank test. Multivariable Cox proportional hazard models were used to evaluate the association among OS, CSS and risk factors of interest.

Results: Of 2 098 patients who underwent RC, 1 243 patients underwent MIRC (1 087 laparoscopic RC and 156 robotic-assisted RC, respectively), while 855 patients underwent ORC. No significant differences were noted in positive surgical margin rate and 90-day postoperative mortality rate. MIRC was associated with less estimated blood loss, more LN yield, higher rate of neobladder diversion, longer operative time, and longer length of hospital stay. There was no significant difference in OS and CSS according to surgical approaches (=0.653, and 0.816, respectively). Subgroup analysis revealed that OS and CSS were not significantly different regardless of the status of extravesical involvement or LN involvement. Multivariable Cox regression analyses showed that the surgical approach was not a significant predictor of OS and CSS.

Conclusions: Our study showed that MIRC was comparable to conventional ORC in terms of OS and CSS.
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http://dx.doi.org/10.1016/j.ajur.2020.06.002DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7385523PMC
July 2020

Early use of endotoxin absorption by oXiris in abdominal septic shock: A case report.

Medicine (Baltimore) 2020 Jul;99(28):e19632

Department of Nephrology, West China Hospital, Sichuan University, 37 Guo Xue Xiang, Chengdu, Sichuan, 610041, China.

Rationale: Septic shock leads to multiple organ failure and increases mortality rate. We reported a critical patient with abdominal septic shock, which was the first case successfully treated with continuous renal replacement therapy (CRRT) and a newly designed endotoxin removal device oXiris in mainland China.

Patient Concerns: A 51-year-old man developed gastric ulcer perforation after resection of a benign peritoneal tumor and had a second abdominal surgery. His blood pressure decreased to 70/40 mm Hg with oliguria, requiring large doses of noradrenaline and intravenous fluid for resuscitation. The abdominal cavity was not sutured after the second open surgery due to severe abdominal infection and distention. His leukocyte count was over 30109/L, while the blood lactic acid was 12.5 mmol/L and procalcitonin (PCT) was >100 ng/mL.

Diagnosis: Since the bacterial culture of peritoneal exudate showed positive with Enterobacter aerogenes and Pseudomonas aeruginosa after the second surgery, and the patient had severe low blood pressure, hyoxemia and oliguria, combined with the laboratory tests results, he was diagnosed with Gram-negative related septic shock, acute kidney injury, and multiple organ dysfunction.

Interventions: CRRT with oXiris membrane was performed for 80hours and followed by AN69 ST membranes during the subsequent 27 days. Antibiotics together with other medical treatment were applied to the patient in the meantime.

Outcomes: At the end of 80 hours treatment with oXiris, PCT of the patient had decreased to 14.52 ng/mL and lactic acid decreased to 4.2 mmol/L. The total sequential organ failure assessment (SOFA) score decreased from 15 to 11. Urine output steadily increased to 250 mL/h, and vital signs and blood pressure were stable without noradrenaline. At the end of the 27 days of conventional CRRT, his kidney function had completely recovered with a total sequential organ failure assessment score (SOFA score) of 6.

Lessons: oXiris, with its enhanced endotoxin adsorption, appeared to accelerate improvement in organ dysfunction and ultimate survival in our patient. In critical patients with abdominal septic shock, oXiris is an important adjunctive consideration to supplement definitive source control and antimicrobial therapy.
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http://dx.doi.org/10.1097/MD.0000000000019632DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7360291PMC
July 2020

Integrated Design of Hierarchical [email protected]@[email protected] Nanobox as Anode Material for Enhanced Lithium Storage Performance.

ACS Appl Mater Interfaces 2020 Apr 17;12(17):19768-19777. Epub 2020 Apr 17.

Shanghai Applied Radiation Institute, School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China.

Transition-metal oxides (TMOs) are potential candidates for anode materials of lithium-ion batteries (LIBs) due to their high theoretical capacity (∼1000 mA h/g) and enhanced safety from suppressing the formation of lithium dendrites. However, the poor electron conductivity and the large volume expansion during lithiation/delithiation processes are still the main hurdles for the practical usage of TMOs as anode materials. In this work, the [email protected]@[email protected] hierarchical nanobox (CNMN) is then proposed and fabricated to solve those issues. The as-prepared nanobox contains hollow cubic CoSnO as a core and dual N-doped carbon-"sandwiched" MnO particles as a shell. As anode materials of LIBs, the hollow and carbon interlayer structures effectively accommodate the volume expansion while dual active TMOs of CoSnO and MnO efficiently increase the specific capacity. Notably, the dual-layer structure of N-doped carbons plays a critical functional role in the incorporated composites, where the inner layer serves as a reaction substrate and a spatial barrier and the outer layer offers electron conductivity, enabling more effective involvement of active anode materials in lithium storage, as well as maintaining their high activity during lithium cycling. Subsequently, the as-prepared CNMN exhibits a high specific capacity of 1195 mA h/g after the 200th cycle at 0.1C and an excellent stable reversible capacity of about 876 mA h/g after the 300th cycle at 0.5C with only 0.07 mA h/g fade per cycle after 300 cycles. Even after a 250 times fast charging/discharging cycle both at 5C, it still retains a reversible capacity of 422.6 mA h/g. We ascribe the enhanced lithium storage performances to the novel hierarchical architectures achieved from the rational design.
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http://dx.doi.org/10.1021/acsami.9b22368DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7304665PMC
April 2020

Transient fault diagnosis for traction control system based on optimal fractional-order method.

ISA Trans 2020 Jul 12;102:365-375. Epub 2020 Mar 12.

School of Automation, Central South University, Changsha, 410083, PR China.

Efficient fault diagnosis of traction control system (TCS) has always been a vital technology for high speed train. Transient fault (TF) derives in harsh operation conditions and manufacturing defect, and its timely diagnosis can prevent catastrophic consequences of TCS or provide degradation information of components. However, TF is easily swallowed by background noise, especially at early stage of failure. This problem brings hardship into feature extraction. Aiming at overcoming the noise problem confronted in weak fault feature extraction, the typical TFs of traction control system are described, and feasibility of speed-based fault diagnosis is demonstrated. Then, an optimal fractional-order method is proposed for TF diagnosis, which suppresses background noise and amplifies the faulty part of the signal. Afterwards, kurtosis and fault duration time are applied to locate the fault component. Three fault diagnosis cases are investigated to validate the application of this methodology.
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http://dx.doi.org/10.1016/j.isatra.2020.03.006DOI Listing
July 2020

The prognostic value of routine preoperative blood parameters in muscle-invasive bladder cancer.

BMC Urol 2020 Mar 19;20(1):31. Epub 2020 Mar 19.

Institute of Urology, Department of Urology, First Affiliated Hospital, Army Medical University (Third Military Medical University), Chongqing, 400038, China.

Background: A routine blood examination is one of the most rapid, convenient and inexpensive clinical examinations that can reflect a patient's inflammatory status and other blood conditions, and the prognostic value of routine preoperative blood parameters in MIBC patients is still unclear, so we evaluated the prognostic value of routine preoperative blood parameters in muscle-invasive bladder cancer (MIBC) following radical cystectomy (RC).

Methods: Data on 202 patients with MIBC who underwent RC at our institution were retrospectively collected between October 2007 and August 2018. The median preoperative neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR) and hemoglobin (HGB) values were used as cutoffs to form the low and high NLR, low and high PLR, and low and high HGB groups, respectively. The clinicopathologic characteristics of each group were compared by chi-square and t tests. Kaplan-Meier survival and multivariate Cox regression analyses were used to analyze prognosis.

Results: The median NLR, PLR and HGB values were 2.42, 112 and 125 g/L, respectively. Kaplan-Meier results showed that the low HGB group had poor progression-free survival (PFS), cancer-specific survival (CSS) and overall survival (OS). A high NLR and high PLR groups correlated only with poor OS. Multivariate Cox analyses showed that pathological T3/4 stage, positive lymph node status and low HGB were independent risk factors for PFS, CSS and OS, and age was the only independent risk factor for OS.

Conclusion: Preoperative peripheral blood HGB is an independent risk factor for the prognosis of MIBC patients. These data suggest that HGB may be a useful prognostic marker for MIBC patients undergoing RC.
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http://dx.doi.org/10.1186/s12894-020-00602-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7082918PMC
March 2020

Ultrastable Li-ion battery anodes by encapsulating SnS nanoparticles in sulfur-doped graphene bubble films.

Nanoscale 2020 Feb 3;12(6):3941-3949. Epub 2020 Feb 3.

Institute for Sustainable Energy/College of Science, Shanghai University, Shanghai 200444, China.

As an anode electrode material for lithium-ion batteries, SnS has high specific capacity and has received widespread attention, but its practical application is still hindered by the low reversibility of the conversion reaction and the large irreversible capacity caused by the solid electrolyte interphase (SEI). In this paper, SnS nanoparticles are encapsulated into a sulfur-doped graphene bubble film ([email protected]) by a scalable electrostatic self-assembly of SnS/graphene oxide and hexadecyl trimethyl ammonium bromide, followed by the thermal decomposition of SnS and sulfur doping in graphene. Due to electrostatic attraction, the SnS nanoparticles are tightly wrapped in multilayer graphene sheets to form a flake-graphite-like structure. Compared with the disordered stacked SnS/graphene sheet composite, the closely packed [email protected] shows a much lower specific surface area and smaller irreversible Li consumption and surface film resistance after lithiation. The [email protected] composite anode exhibits great initial coulombic efficiency (83.2%), which is the highest value among the chemically synthesized SnS anodes. It also presents unprecedented cycling stability (1462 mA h g after 200 cycles at 0.1 A g and 1020 mA h g after 500 cycles at 1 A g) and superior rate capabilities (750 mA h g at 5 A g) upon Li storage, which demonstrates its excellent electrochemical performance and great potential as a negative electrode material for lithium-ion batteries.
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http://dx.doi.org/10.1039/c9nr10608aDOI Listing
February 2020

Refinement Surgical Technique, and Perioperative and Functional Outcomes in Patients With Robotic Intracorporeal Hautmann Orthotopic Neobladder.

Urology 2020 Apr 30;138:45-51. Epub 2020 Jan 30.

Department of Urology, Urology Institute of PLA, Southwest Hospital, Third Military Medical University (Army Medical University), Sha Pingba, Chongqing, China. Electronic address:

Objective: To illustrate our refinement technique for robotic intracorporeal orthotopic Hautmann neobladder with adherence to open surgical principles and evaluate perioperative and functional outcomes.

Patients And Methods: Robot-assisted radical cystectomy with intracorporeal Hautmann orthotopic neobladder was performed by the same surgeon in 40 patients with bladder cancer from November 2017 to March 2019. Baseline demographics, pathologic data, 90-day complications, and functional outcomes at both 6 and 12 months were evaluated with questionnaire and urodynamic analysis.

Results: Median follow-up was 14 months (range 4-20). Median operative time was 320 (230-500) minutes, and the estimated blood loss was 300 (100-2000) mL. No conversion to the open technique was reported. The overall 90-day complication rate was 45%, and the high-grade complication rate was only 10%. The daytime satisfactory continence rate was 90% at both 6 months (30 patients) and 12 months (20 patients), while the night-time satisfactory continence rate was 76.7% and 80.0% at 6 months and 12 months, respectively. One patient underwent clean intermittent catheterization. The cohort had minimal postvoid residual volume, normal compliance, and a mean capacity of 328.7 cm (range 170-500) at 6 months postoperatively.

Conclusion: Our preliminary data indicate that robotic intracorporeal Hautmann neobladder configuration is a feasible surgical technique and can achieve a low pressure and sufficient capacity for satisfactory early voiding patterns. Refinement of the stepwise process can effectively decrease the time of the operation. Long-term functional and oncological outcomes remain to be evaluated with longer follow-up and more cases.
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http://dx.doi.org/10.1016/j.urology.2020.01.025DOI Listing
April 2020

An optimized Agrobacterium tumefaciens-mediated transformation system for random insertional mutagenesis in Fonsecaea monophora.

J Microbiol Methods 2020 03 8;170:105838. Epub 2020 Jan 8.

Department of Dermatology and Venerology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China; Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China. Electronic address:

Chromoblastomycosis (CBM) is a chronic cutaneous or subcutaneous mycosis that is prevalent worldwide. Though CBM tends not to be fatal, it is difficult to treat and complications can include chronic, marked lesions, lymphatic damage, and neoplastic transformation. Fonsecaea monophora, as a new species segregated from Fonsecaea pedrosoi, is the predominant causative pathogen of CBM in southern China. However, research about F. monophora has been limited, which may be due to a lack of an effective genetic manipulation system for F. monophora. In this study, we successfully established a random insertional mutagenesis system by Agrobacterium tumefaciens-mediated transformation (ATMT) in F. monophora for the first time. In order to improve the efficiency of ATMT, various co-culture conditions were optimized, including: acetosyringone (AS) concentrations, co-culture duration, ratio of bacteria to conidia, and the A. tumefaciens strains. In addition, thermal asymmetric interlaced polymerase chain reaction (TAIL-PCR) was performed to identify the transferred DNA (T-DNA) flanking sequences of the F. monophora transformants. The valuable transformants obtained in this study will be used for research in the future.
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http://dx.doi.org/10.1016/j.mimet.2020.105838DOI Listing
March 2020

Structural phase transformation from SnS/reduced graphene oxide to SnS/sulfur-doped graphene and its lithium storage properties.

Nanoscale 2020 Jan;12(3):1697-1706

School of Environmental and Chemical Engineering, Shanghai University, Shanghai, 200444, China.

In this work, we demonstrate an interesting structural phase transition from SnS2/reduced graphene oxide to SnS/sulfur-doped graphene at a moderate calcination temperature of 500 °C under an inert atmosphere. It is discovered that SnS2 chemically bound to rGO with a weakened C-S bond is easier to break and decompose into SnS, whereas it is difficult for pure-phase crystalline SnS2 to experience phase transformation at this temperature. Moreover, the thin-layered structure of SnS2 and rGO is an important factor for the effective doping of the dissociated Sx into graphene. Density functional theory calculations also reveal the feasibility of the structural phase transition process. Morphology characterization shows that partial SnS maintains the original nanosheet structure (∼100 nm) and the others are decomposed into tiny nanoparticles (10-20 nm). A high S-doping amount reduces the irreversible lithium storage sites on graphene, and the first coulombic efficiency is as high as 81.7%. In addition, thin-layered and small-sized SnS can alleviate the structural damage caused by volume expansion and shrinkage; therefore, a high specific capacity of 893.9 mA h g-1 is retained after 100 cycles.
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http://dx.doi.org/10.1039/c9nr08075aDOI Listing
January 2020

Well-defined [email protected] hollow heterostructured nanocubes with enhanced dissociation kinetics for overall water splitting.

Nanoscale 2020 Jan 11;12(1):326-335. Epub 2019 Dec 11.

Shanghai Electrochemical Energy Devices Research Center, School of Chemistry and Chemical Engineering and State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai, 200240, China.

Hollow heterostructures have tremendous advantages in electrochemical energy storage and conversion areas due to their unique structure and composition characteristics. Here, we report the controlled synthesis of hollow CoSe nanocubes decorated with ultrathin MoSe nanosheets ([email protected]) as an efficient and robust bifunctional electrocatalyst for overall water splitting in a wide pH range. It is found that integrating ultrathin MoS nanosheets with hollow CoSe nanocubes can provide abundant active sites, promote electron/mass transfer and bubble release and facilitate the migration of charge carriers. Additionally, the surface electron coupling in the heterostructures enables it to serve as a source of sites for H and/or OH adsorption, thus reducing the activation barrier for water molecules adsorption and dissociation. As a result, the title compound, [email protected] hollow heterostructures, exhibits an overpotential of 183 mV and 309 mV at a current density of 10 mA cm toward hydrogen evolution reactions and oxygen evolution reactions in 1.0 M KOH, respectively. When applied as both cathode and anode for overall water splitting, a low battery voltage of 1.524 V is achieved along with excellent stability for at least 12 h. This work provides a new idea for the design and synthesis of high-performance catalysts for electrochemical energy storage and conversion.
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http://dx.doi.org/10.1039/c9nr08751fDOI Listing
January 2020
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