Aligned Conjugated Polymer Nanofiber Networks in an Elastomer Matrix for High-Performance Printed Stretchable Electronics.

Conjugated polymer films are promising in wearable X-ray detection. However, achieving optimal film microstructure possessing good electrical and detection performance under large deformation via scalable printing remains challenging. Herein, we report bar-coated high-performance stretchable films based on a conjugated polymer P(TDPP-Se) and elastomer SEBS blend by optimizing the solution-processing conditions. The moderate preaggregation in solution and prolonged growth dynamics from a solvent mixture with limited dissolving capacity is critical to forming aligned P(TDPP-Se) chains/crystalline nanofibers in the SEBS phase with enhanced π-π stacking for charge transport and stress dissipation. The film shows a large elongation at break of >400% and high mobilities of 5.29 cm2 V-1 s-1 at 0% strain and 1.66 cm2 V-1 s-1 over 500 stretch-release cycles at 50% strain, enabling good X-ray imaging with a high sensitivity of 1501.52 µC Gyair-1 cm-2. Our work provides a morphology control strategy toward high-performance conjugated polymer film-based stretchable electronics.

Thienoisoindigo-Based Conjugated Polymers Synthesized by Direct Arylation Polycondensation.

A series of thienoisoindigo (TIG)-based conjugated polymers (CPs) with high molecular weights are synthesized by direct arylation polycondensation (DArP) by using TIG derivatives as CBr monomer and multi-halogenated thiophene derivatives, i.e., (E)-1,2-bis(3,4-difluorothien-2-yl)ethene (4FTVT), (E)-1,2-bis(3,4-dichlorothien-2-yl)ethene (4ClTVT), 3,3',4,4'-tetrafluoro-2,2'-bithiophene (4FBT), and 3,3',4,4'-tetrachloro-2,2'-bithiophene (4ClBT), as CH monomers. Density functional theory (DFT) calculations reveal the high selectivity between α-CH bonds in 4FTVT, 4ClTVT, 4FBT, and 4ClBT and ß-CH bonds in TIG CBr monomer. All four resulting CPs exhibit low optical bandgaps of ca. 1.20 eV and ambipolar transport characteristics with both electron and hole mobility above 0.1 cm2  V-1  s-1 as elaborated with organic thin-film transistors (OTFTs). The polymer TIG-4FTVT delivers the best device performance. With this polymer, n-channel OTFTs with electron mobility up to 1.67 cm2  V-1  s-1 and p-channel OTFTs with hole mobility up to 0.62 cm2  V-1  s-1 are fabricated by modifying source/drain electrodes with polyethylenimine ethoxylated (PEIE) and MoO3 , respectively, to selectively inject electrons and holes.

Universal Design and Efficient Synthesis for High Ambipolar Mobility Emissive Conjugated Polymers.

High ambipolar mobility emissive conjugated polymers (HAME-CPs) are perfect candidates for organic optoelectronic devices, such as polymer light emitting transistors. However, due to intrinsic trade-off relationship between high ambipolar mobility and strong solid-state luminescence, the development of HAME-CPs suffers from high structural and synthetic complexity. Herein, a universal design principle and simple synthetic approach for HAME-CPs are developed. A series of simple non-fused polymers composed of charge transfer units, π bridges and emissive units are synthesized via a two-step microwave assisted C-H arylation and direct arylation polymerization protocol with high total yields up to 61 %. The synthetic protocol is verified valid among 7 monomers and 8 polymers. Most importantly, all 8 conjugated polymers have strong solid-state emission with high photoluminescence quantum yields up to 24 %. Furthermore, 4 polymers exhibit high ambipolar field effect mobility up to 10-2 cm2 V-1 s-1, and can be used in multifunctional optoelectronic devices. This work opens a new avenue for developing HAME-CPs by efficient synthesis and rational design.

An n-Type Open-Shell Conjugated Polymer with High-Spin Ground-State and High Intrinsic Electrical Conductivity.

Open-shell conjugated polymers with a high intrinsic conductivity and high-spin ground state hold considerable promise for applications in organic electronics and spintronics. Herein, two novel acceptor-acceptor (A-A) conjugated polymers based on a highly electron-deficient quinoidal benzodifurandione unit have been developed, namely DPP-BFDO-Th and DPP-BFDO. The incorporation of the quinoidal moiety into the polymers backbones enables deeply aligned lower-lying lowest unoccupied molecular orbital (LUMO) levels of below -4.0 eV. Notably, DPP-BFDO exhibits an exceptionally low LUMO (-4.63 eV) and a high-spin ground state characterized by strong diradical characters. Moreover, a self-doping through intermolecular charge-transfer is observed for DPP-BFDO, as evidenced by X-ray photoelectron spectroscopy (XPS) studies. The high carrier concentration in combination with a planar and linear conjugated backbone yields a remarkable electrical conductivity (σ) of 1.04 S cm-1 in the "undoped" native form, ranking among the highest values reported for n-type radical-based conjugated polymers. When employed as an n-type thermoelectric material, DPP-BFDO achieves a power factor of 12.59 µW m-1 K-2. Furthermore, upon n-doping, the σ could be improved to 65.68 S cm-1. This study underscores the great potential of electron-deficient quinoidal units in constructing dopant-free n-type conductive polymers with a high-spin ground state and exceptional intrinsic conductivity.

Improving the intrinsic activity of ultrathin 2D-2D heterostructures by bridge-bonded Ni-O-Ti ligands for efficient oxygen evolution.

The integration of ultrathin two-dimensional (2D) semiconductors with other conductive 2D materials to form hybrid electrocatalysts with abundant heterointerfaces can enhance the electrocatalytic activity by facilitating interfacial charge transfer. However, the hybrid electrocatalysts with weak interfacial bonding have limited effect on the electrocatalytic performance because the intrinsic activity of interfacial sites cannot be altered by weak interfacial interactions. As a proof-of-concept, we design ultrathin 2D-2D heterostructures with bridge-bonded Ni-O-Ti ligands based on single-layered Ti3C2TxMXene and metal hydroxides, and further reveal the structure-activity correlation between interfacial bonding and electrocatalytic oxygen evolution reaction by combining theoretical and experimental studies. Density functional theory calculations reveal the modulation of the electronic structure of interfacial metal sites after the formation of bridged interfacial Ni-O-Ti bonding. Compared with the hydrogen-bond-linked heterostructure, the ultrathin 2D-2D heterostructure with bridge-bonded Ni-O-Ti ligands shows enhanced intrinsic activity and stability towards electrocatalytic oxygen evolution with a very low overpotential of 205 mV at 10 mA cm-2and the long-term durability. This work provides a new understanding and approach for the design and development of 2D hybrid catalysts with highly efficient electrocatalytic activity.

Conjugated Polymers from Direct Arylation Polycondensation of 3,4-Difluorothiophene-Substituted Aryls: Synthesis and Properties.

3,4-Difluorothiophene-substituted aryls, i.e., 1,4-bis(3,4-difluorothiophen-2-yl)-benzene (Ph-2FTh), 1,4-bis(3,4-difluorothiophen-2-yl)-2,5-difluorobenzene (2FPh-2FTh), and 4,7-bis(3,4-difluorothiophen-2-yl)-2,1,3-benzothiadiazole (BTz-2FTh), are synthesized as C─H monomers for the synthesis of conjugated polymers (CPs) via direct arylation polycondensation (DArP) with diketopyrrolopyrrole (DPP) and isoindigo (IID) derivatives as C─Br monomers. The Gibbs free energies of activation for direct arylation (ΔG298 K , kcal mol-1 ) for α─C─H bonds of thiophene moieties as calculated by density functional theory (DFT) are 14.3, 16.5, and 16.4 kcal mol-1 for Ph-2FTh, 2FPh-2FTh and BTz-2FTh, respectively, meaning that inserting an electron-deficient unit in 3,3',4,4'-tetrafluoro-2,2'-bithiophene (4FBT, ΔG298K : 14.6 kcal mol-1 ) may cause a reactivity decrease of the C─H monomers. Photophysical and semiconducting properties of the resulting six CPs (i.e., DPP-Ph, DPP-2FPh, DPP-BTz, 2FIID-Ph, 2FIID-2FPh, and 2FIID-BTz) are characterized in detail. DPP-based CPs show ambipolar transport properties while IID-based ones exhibited n-type behavior owing to the deeper frontier molecular orbital energy levels of IID-based CPs. With source/drain electrodes modified with polyethylenimine ethoxylated, n-channel organic thin-film transistors with maximum electron mobility of 0.40, 0.54, 0.29, 0.05, 0.16, and 0.01 cm2 V-1 s-1 for DPP-Ph, DPP-2FPh, DPP-BTz, 2FIID-Ph, 2FIID-2FPh, and 2FIID-BTz, respectively, are fabricated. DPP-2FPh exhibits the best device performance due to the good film morphology and the highest intermolecular packing order.

Analysis on the flocculation characteristics of algal organic matters.

Algal organic matters (AOM) produced by cyanobacteria is an important part of the organic pollution and deterioration of water quality. Due to the complex composition, high solubility and easy dispersion of AOM, its flocculation characteristics become an important factor affecting the treatment for cyanobacteria-containing water. In this study, the cyanobacteria both in the Lab- and Taihu-environment were taken as research objects, aiming at the flocculation characteristic analysis of their extracellular organic matters (EOM) and intracellular organic matters (IOM) with the release risks. Results showed that EOM required more coagulant dosage than IOM and its removal effect was relatively lower. The complex water environment factors in Taihu Lake might cause easier separation of cyanobacterial AOM, which increased the removal efficiency of EOM and IOM by 11.05-26.18% and 8.54.-12.8%, respectively. The flocculation efficiency of cyanobacterial AOM was not only affected by the zeta potential driven charge neutralization, but also by the component distribution and content of AOM. Aromatic protein-like microbial metabolites were the main combination targets of coagulants rather than humic acids and fulvic acids. The wider floc particle size range and worse floc uniformity of cyanobacterial EOM was also one of the reasons for its poor coagulation effect. This paper provides an important theoretical basis and data support for the targeted flocculation and removal of cyanobacterial AOM.

Component structure and characteristic analysis of cyanobacterial organic matters.

The characteristic analysis of cyanobacterial organic matters is an important premise of cyanobacterial organic pollution control. This paper investigated the component structure characteristics of algal organic matters (AOM) secreted and released by cyanobacteria in laboratory culture and actual Taihu Lake environment by spectroscopic quantitative and qualitative methods. Results showed that the secretion amount of AOM was mainly 4-6 µg COD/106 cells during the growth period of Microcystis aeruginosa, and the content ratio of extracellular organic matters (EOM) to intracellular organic matters (IOM) gradually increased from 0.83 in adaptation and logarithmic period to 3.33 in stable and decay period. The secretion of IOM showed a decrease trend, which indicated the decrease of its synthesis or the gradual infiltration and loss caused by cell membrane damage. From the component characteristics, the EOM had lower SUVA value and higher proportion of small molecular substances with molecular weight <3 kDa, indicating its more difficult to separate from water than IOM. Compared with the laboratory culture environment, the actual Taihu Lake resulted in more obvious characteristic heterogeneity of cyanobacteria EOM and IOM.

Enhanced stability of silver nanowire transparent conductive films against ultraviolet light illumination.

Silver nanowires are susceptible to degradation under ultraviolet (UV) light illumination. Encapsulating silver nanowire transparent conductive films (AgNW TCFs) with UV shielding materials usually result in the increasing of the sheet resistance or the decrease of the visible light transparency. Herein, we combine a reducing species (FeSO4) and a thin layer (overcoating) of UV shielding material to solve the stability and the optical performance issues simultaneously. The AgNW TCFs show excellent stability under continuous UV light illumination for 14 h, and their sheet resistance varies only 6%. The dramatic enhancement of the stability against UV light illumination for as-obtained TCFs will make them viable for real-world applications in touch panels and displays.

Multi-Scale MXene/Silver Nanowire Composite Foams with Double Conductive Networks for Multifunctional Integration.

With the onset of the 5G era, wearable flexible electronic devices have developed rapidly and gradually entered the daily life of people. However, the vast majority of research focuses on the integration of functions and performance improvement, while ignoring electromagnetic hazards caused by devices. Herein, the 3D double conductive networks are constructed through a repetitive vacuum-assisted dip-coating technique to decorate the 2D MXene and 1D silver nanowires on the melamine foam. Benefiting from the unique porous structure and multi-scale interconnected frame, the resultant composite foam exhibited high electrical conductivity, low density, superb electromagnetic interference shielding (48.32 dB), and Joule heating performance (up to 90.8 °C under 0.8 V). Furthermore, a single-electrode triboelectric nanogenerator (TENG) with powerful energy harvesting capability is assembled by combining the composite foam with an ultra-thin Ecoflex film and a polyvinylidene fluoride film. Simultaneously, the foam-based TENG can also be considered a reliable wearable sensor for monitoring activity patterns in different parts of the human body. The versatility and scalable manufacturing of high-performance composite foams will provide new design ideas for the development of next-generation flexible wearable devices.

Toward grouped-reservoir computing: organic neuromorphic vertical transistor with distributed reservoir states for efficient recognition and prediction.

Reservoir computing has attracted considerable attention due to its low training cost. However, existing neuromorphic hardware, focusing mainly on shallow-reservoir computing, faces challenges in providing adequate spatial and temporal scales characteristic for effective computing. Here, we report an ultra-short channel organic neuromorphic vertical transistor with distributed reservoir states. The carrier dynamics used to map signals are enriched by coupled multivariate physics mechanisms, while the vertical architecture employed greatly increases the feedback intensity of the device. Consequently, the device as a reservoir, effectively mapping sequential signals into distributed reservoir state space with 1152 reservoir states, and the range ratio of temporal and spatial characteristics can simultaneously reach 2640 and 650, respectively. The grouped-reservoir computing based on the device can simultaneously adapt to different spatiotemporal task, achieving recognition accuracy over 94% and prediction correlation over 95%. This work proposes a new strategy for developing high-performance reservoir computing networks.

Constructing gradient reflection and scattering porous framework in composite aerogels for enhanced microwave absorption.

Developing high-performance microwave absorption (MA) materials becomes an urgent concern in the field of electromagnetic protection. Constructing porous framework is an efficient approach to MA owing to the abilities of adjusting impedance matching and providing more reflection and scattering paths for electromagnetic waves. Herein, a cellulose nanofibril (CNF)/honeycomb-like carbon-shell encapsulated FeCoNi@C/carbon nanotube (CNT) composite aerogel was fabricated via a facile freeze-drying method. The super-lightweight composites showed a distinctive gradient structure for reflection and scattering inside aerogel pores, micrometer small pores, and nano-fillers on the pore walls. The composite aerogel showed an ideal minimum reflection loss (RLmin) of -43.6 dB and remarkable adjustable effective absorption bandwidth (EAB) of 12.18 GHz due to good impedance matching, unique gradient porous structure, and synergies of multiple loss mechanisms. Therefore, this work will provide a viable strategy to improve the MA capability of absorbers by taking full advantage of constructing gradient reflection and scattering porous structure.

Endowing improved osteogenic activities with collagen membrane by incorporating biocompatible iron oxide nanoparticles.

Introduction: Collagen-based scaffolds, renowned for their exceptional biocompatibility, have garnered attention as promising scaffolds for advancing bone tissue regeneration. Nevertheless, these scaffolds possess inherent limitations, such as notably compromised osteo-conductivity and osteo-inductivity. Methods: Our study focused on enhancing the mechanical properties and osteogenic bioactivities of bovine-derived collagen membranes (CMs) from the Achilles tendon by incorporating FDA-approved iron oxide nanoparticles (IONPs), termed as IONP-CM. Three types of IONP-CMs (IONP-CM-0.5, IONP-CM-1, and IONPCM-1.5) were constructed by altering the amounts of feeding IONPs. Results: Surface topography analysis demonstrated comparable characteristics between the IONP-CM and neat CM, with the former exhibiting augmented mechanical properties. In vitro evaluations revealed the remarkable biocompatibility of IONP-CMs toward mouse calvarial pre-osteoblast MC3T3-E1 cells, concurrently stimulating osteogenic differentiation. Mechanistic investigations unveiled that the osteogenic differentiation induced by IONP-CMs stemmed from the activation of the Wnt/ß-catenin signaling pathway. Furthermore, in vivo bone regeneration assessment was performed by implanting IONP-CMs into the radial defect in rabbits. Results derived from micro-computed tomography and histological analyses unequivocally substantiated the capacity of IONP-CMs to expedite bone repair processes. Discussion: IONP-CMs emerged as scaffolds boasting exceptional biocompatibility and enhanced osteogenic properties, positioning them as promising candidates for facilitating bone tissue regeneration.

Specific Blood RNA Profiles in Individuals with Acute Spinal Cord Injury as Compared with Trauma Controls.

Background: Spinal cord injury (SCI) is known to cause a more robust systemic inflammatory response than general trauma without CNS injury, inducing severe secondary organ damage, especially the lung and liver. Related studies are principally focused on the mechanisms underlying repair and regeneration in the injured spinal cord tissue. However, the specific mechanism of secondary injury after acute SCI is widely overlooked, compared with general trauma. Methods: Two datasets of GSE151371 and GSE45376 related to the blood samples and spinal cord after acute SCI were selected to identify the differentially expressed genes (DEGs). In GSE151371, functional enrichment analysis on specific DEGs of blood samples was performed. And the top 15 specific hub genes were identified from intersectional genes between the specific upregulated DEGs of blood samples in GSE151371 and the upregulated DEGs of the spinal cord in GSE45376. The specific functional enrichment analysis and the drug candidates of the hub genes and the miRNAs-targeted hub genes were also analyzed and predicted. Results: DEGs were identified, and a total of 64 specific genes were the intersection of upregulated genes of the spinal cord in GSE45376 and upregulated genes of human blood samples in GSE151371. The top 15 hub genes including HP, LCN2, DLGAP5, CEP55, HMMR, CDKN3, PRTN3, SKA3, MPO, LTF, CDC25C, MMP9, NEIL3, NUSAP1, and CD163 were calculated from the 64 specific genes. Functional enrichment analysis of the top 15 hub genes revealed inflammation-related pathways. The predicted miRNAs-targeted hub genes and drug candidates of hub genes were also performed to put forward reasonable treatment strategies. Conclusion: The specific hub genes of acute SCI as compared with trauma without CNS injury were identified. The functional enrichment analysis of hub genes showed a specific immune response. Several predicted drugs of hub genes were also obtained. The hub genes and the predicted miRNAs may be potential biomarkers and therapeutic targets and require further validation.

Disrupted Functional Connectivity of the Amygdala Predicts the Efficacy of Non-steroidal Anti-inflammatory Drugs in Migraineurs Without Aura.

Machine learning (ML) has been largely applied for predicting migraine classification. However, the prediction of efficacy of non-steroidal anti-inflammatory drugs (NSAIDs) in migraine is still in the early stages. This study aims to evaluate whether the combination of machine learning and amygdala-related functional features could help predict the efficacy of NSAIDs in patients with migraine without aura (MwoA). A total of 70 MwoA patients were enrolled for the study, including patients with an effective response to NSAIDs (M-eNSAIDs, n = 35) and MwoA patients with ineffective response to NSAIDs (M-ieNSAIDs, n = 35). Furthermore, 33 healthy controls (HCs) were matched for age, sex, and education level. The study participants were subjected to resting-state functional magnetic resonance imaging (fMRI) scanning. Disrupted functional connectivity (FC) patterns from amygdala-based FC analysis and clinical characteristics were considered features that could promote classification through multivariable logistic regression (MLR) and support vector machine (SVM) for predicting the efficacy of NSAIDs. Further, receiver operating characteristic (ROC) curves were drawn to evaluate the predictive ability of the models. The M-eNSAIDs group exhibited enhanced FC with ipsilateral calcarine sulcus (CAL), superior parietal gyrus (SPG), paracentral lobule (PCL), and contralateral superior frontal gyrus (SFG) in the left amygdala. However, the M-eNSAIDs group showed decreased FC with ipsilateral caudate nucleus (CAU), compared to the M-ieNSAIDs group. Moreover, the M-eNSAIDs group showed higher FC with left pre-central gyrus (PreCG) and post-central gyrus (PoCG) compared to HCs. In contrast, the M-ieNSAIDs group showed lower FC with the left anterior cingulate cortex (ACC) and right SFG. Furthermore, the MwoA patients showed increased FC with the left middle frontal gyrus (MFG) in the right amygdala compared to HCs. The disrupted left amygdala-related FC patterns exhibited significant correlations with migraine characteristics in the M-ieNSAIDs group. The MLR and SVM models discriminated clinical efficacy of NSAIDs with an area under the curve (AUC) of 0.891 and 0.896, sensitivity of 0.971 and 0.833, and specificity of 0.629 and 0.875, respectively. These findings suggest that the efficacy of NSAIDs in migraine could be predicted using ML algorithm. Furthermore, this study highlights the role of amygdala-related neural function in revealing underlying migraine-related neuroimaging mechanisms.

Fabrication of Submicro-Nano Structures on Polyetheretherketone Surface by Femtosecond Laser for Exciting Cellular Responses of MC3T3-E1 Cells/Gingival Epithelial Cells.

PURPOSE: Polyetheretherketone (PEEK) exhibits high mechanical strengths and outstanding biocompatibility but biological inertness that does not excite the cell responses and stimulate bone formation. The objective of this study was to construct submicro-nano structures on PEEK by femtosecond laser (FSL) for exciting the responses of MC3T3-E1 cells and gingival epithelial (GE) cells, which induce regeneration of bone/gingival tissues for long-term stability of dental implants. MATERIALS AND METHODS: In this study, submicro-nano structures were created on PEEK surface by FSL with power of 80 mW (80FPK) and 160 mW (160FPK). RESULTS: Compared with PEEK, both 80FPK and 160FPK with submicro-nano structures exhibited elevated surface performances (hydrophilicity, surface energy, roughness and protein absorption). Furthermore, in comparison with 80FPK, 160FPK further enhanced the surface performances. In addition, compared with PEEK, both 80FPK and 160FPK significantly excited not only the responses (adhesion, proliferation, alkaline phosphatase [ALP] activity and osteogenic gene expression) of MC3T3-E1 cells but also responses (adhesion as well as proliferation) of GE cells of human in vitro. Moreover, in comparison with 80FPK, 160FPK further enhanced the responses of MC3T3-E1 cells/GE cells. CONCLUSION: FSL created submicro-nano structures on PEEK with elevated surface performances, which played crucial roles in exciting the responses of MC3T3-E1 cells/GE cells. Consequently, 160FPK with elevated surface performances and outstanding cytocompatibility would have enormous potential as an implant for dental replacement.

The influence of extracellular polymeric substances on the coagulation process of cyanobacteria.

The hydrophobicity and flocculation properties of cyanobacterial cells are closely related to their extracellular polymeric substances (EPS). During the treatment of drinking water, the coagulation and removal of EPS-wrapped cyanobacterial particles from natural water sources is very difficult. In this work, a series of surface characteristics of cyanobacterial cells with different EPS fractions were analyzed to evaluate their influences on the coagulation process. With the removal of EPS, the coagulation efficiency of cyanobacteria was gradually improved. The intracellular microcystin release showed that the cyanobacterial cells in each EPS removal phase were almost intact with few broken cells. The surface of cyanobacterial cells had higher hydrophobicity and lower zeta potentials with each step of the EPS extraction, which improved the ratio of particles that were in an unstable state. Furthermore, the deeper the EPS extraction phase, the larger the decreased in size of cyanobacterial particles, thus increasing their specific surface area for adsorption with coagulant. It was concluded that the coagulation mechanism of EPS-wrapped cyanobacterial particles was: the cyanobacterial cells were first peeled off through attraction by opposite charges from the coagulant, and then they were adsorbed before settling down. This study provides a scientific basis for the removal of cyanobacteria by enhancing coagulation.

Metal-Organic Framework-Derived Hierarchical (Co,Ni)Se2@NiFe LDH Hollow Nanocages for Enhanced Oxygen Evolution.

High-efficient electrocatalysts are crucial for fuel cell applications; however, the whole cell performance is generally restricted by the anodic part because of the sluggish kinetics involved in the oxygen evolution reaction (OER) process. Herein, a hierarchical hollow (Co,Ni)Se2@NiFe layered double hydroxide (LDH) nanocage was synthesized by deriving from the metal-organic framework (MOF) of ZIF-67. Concretely, it involves first fabrication of hollow rhombic (Co,Ni)Se2 nanocages and then deposition of NiFe LDH nanosheets on the surface of nanocages. Notably, the incorporation of Ni into Co-based ZIF-67 (via ion-exchange) could tail the atomic arrangement of the MOF, exposing more additional active sites in the following selenization treatment. The as-synthesized (Co,Ni)Se2@NiFe LDH demonstrates splendid OER performance with a small overpotential of 277 mV (to launch a current density of 10 mA cm-2), a small Tafel slope of 75 mV dec-1, and robust durability (a slight stability decay of 5.1% after 17 h of continuous test), not only surpassing the commercial RuO2 but also being comparable/superior to most reported nonprevious metal-based catalysts. Upon analysis, the outstanding OER performance is attributed to the optimized adsorption/desorption nature of iron and nickel/cobalt toward the oxygenated species and partial delocalization of spin status at the interface via the bridging O2-. This work represents a solid step toward exploration of advanced catalysts with deliberate experimental design and/or atom tailoring.

Geographic Distribution and Genetic Diversity of Rice Stripe Mosaic Virus in Southern China.

Rice stripe mosaic virus (RSMV) transmitted by the leafhopper Recilia dorsalis is a tentative new species in the genus Cytorhabdovirus identified recently in South China. To explore its geographic distribution and genetic diversity, field investigation and viral whole-genome sequencing were conducted in this study. The results indicated that RSMV was present in the rice samples collected across southern China. Twelve representative samples from different geographical regions were selected for viral whole-genome sequencing and the viral genome variation was analyzed in combination with a previously reported RSMV isolate. Identity analysis showed that the genome sequences of 13 RSMV isolates were highly conserved with nucleotide identities over 99.4%. There was a strong negative selection pressure during the evolution of RSMV with more transitions (72.08%) than transversions (27.92%) found between the RSMV isolates. Among the seven genes encoded by RSMV, the P gene was the most variable, followed by N, M, L, and G; the P3 and P6 amino acid sequences were not found to be mutated and no mutations were found in the non-coding region. A phylogenetic tree based on the RSMV whole-genome nucleotide sequences revealed that all RSMV isolates clustered in two groups based on geographical origin. Notably, the L proteins of the Guangxi and Hainan isolates had five and one specific amino acid sites, respectively, suggesting that the L gene has undergone environmental adaptive variation during the dispersal of RSMV.