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In situ constructing hetero-interface, and revealing its interfacial polarization is challenging. Here, the Mo defect-induced interfacial polarization on MoC(−)/NC(+) interface was clarified, and for the first time, directly observed by hologram.

Injection-production operation parameters such as the minimum injection gas pressure (IGP:operation pressure), IGP interval, minimum IGP residence time and injection-production cycle period of long-term operation of underground salt rock gas storage will not only affect the storage capacity and working ability of gas storage but also be crucial to the safety and stability of the surrounding rock. A 3D geomechanical model of a salt cavern was established by WinUbro to study the stability of gas storage in the operation period. Five evaluation criteria for predicting the feasibility and stability of gas storage were comprehensively considered, including deformation, expansion safety factor, volume shrinkage, plastic zone and sensitivity. The stability of the surrounding rock of the cavern under different injection-production operation parameters and the degree of influence of each parameter on the stability of gas storage during the operation period are compared. The results show that the displacement of the surrounding rock and its deformation distribution range, the displacement of the roof of the cavern, the expansion coefficient of the surrounding rock of the salt cavern and the volume shrinkage rate of the salt cavern decrease significantly with the injection-production operation parameters. The plastic zone of the salt cavern increases with the rise in the IGP interval and the increase in the minimum IGP; however, the minimum IGP residence time and injection-production period have no obvious influence on the plastic zone of the salt cavern. The IGP interval and the minimum IGP have a positive influence on the plastic zone of the salt cavern, however, the minimum IGP residence time and injection-production period have no obvious influence on the plastic zone. The sensitivity coefficients of each injection-production operation parameter are ranked, from largest to smallest, as follows: IGP interval, minimum IGP, minimum IGP residence time and injection-production cycle. This conclusion can provide a theoretical basis for further optimizing the operation scheme design of salt rock gas reservoirs and ensuring the safety and stability of the long-term injection-production process of layered salt rock gas storage.

We reported that A-kinase anchoring protein 5 (AKAP5) played a role in cardiomyocyte apoptosis after hypoxia-reoxygenation (H/R). The role of AKAP5 in cardiomyocyte hypertrophy has not been fully elucidated. Herein we investigated whether AKAP5 regulates cardiomyocyte hypertrophy through calcium/calmodulin-dependent protein kinase II (CaMKII). After H/R, deficiency of AKAP5 in H9C2 cardiomyocytes and neonatal rat cardiac myocytes activated CaMKII and stimulated cardiomyocyte hypertrophy. AKAP5 upregulation limited this. Low expression of AKAP5 increased CaMKII interaction with histone deacetylases 4/5 (HDAC4/5) and increased nuclear export of HDAC4/5. In addition, AKAP5 interactions with protein kinase A (PKA) and phospholamban (PLN) were diminished. Moreover, the phosphorylation of PLN was decreased, and intracellular calcium increased. Interference of this process with St-Ht31 increased CaMKII signaling, decreased PLN phosphorylation and promoted post-H/R cell hypertrophy. And PKA-anchoring deficient AKAP5ΔPKA could not attenuate hypoxia-reoxygenation-induced cardiomyocyte hypertrophy, but AKAP5 could. Altogether, AKAP5 downregulation exacerbated H/R-induced hypertrophy in cardiomyocytes. This was due to, in part, to less in AKAP5-PKA interaction and the accumulation of intracellular Ca

Fundamental understanding of the dependence between the structure and composition on the electrochemical CO2 reduction reaction (CO2 RR) would guide the rational design of highly efficient and selective electrocatalysts. A major impediment to the deep reduction CO2 to multi-carbon products is the complexity of carbon-carbon bond coupling. The chemically well-defined catalysts with atomically dispersed dual-metal sites are required for these C-C coupling involved processes. Here, we developed a catalyst (BIF-102NSs) that features Cl- bridged dimer copper (Cu2 ) units, which delivers high catalytic activity and selectivity for C2 H4 . Mechanistic investigation verifies that neighboring Cu monomers not only perform as regulator for varying the reaction barrier, but also afford distinct reaction paths compared with isolated monomers, resulting in greatly improved electroreduction performance for CO2 .

Single-atom catalysts (SACs) are being pursued as economical electrocatalysts. However, their low active-site loading, poor interactions, and unclear catalytic mechanism call for significant advances. Herein, atomically dispersed Ni/Co dual sites anchored on nitrogen-doped carbon (a-NiCo/NC) hollow prisms are rationally designed and synthesized. Benefiting from the atomically dispersed dual-metal sites and their synergistic interactions, the obtained a-NiCo/NC sample exhibits superior electrocatalytic activity and kinetics towards the oxygen evolution reaction. Moreover, density functional theory calculations indicate that the strong synergistic interactions from heteronuclear paired Ni/Co dual sites lead to the optimization of the electronic structure and the reduced reaction energy barrier. This work provides a promising strategy for the synthesis of high-efficiency atomically dispersed dual-site SACs in the field of electrochemical energy storage and conversion. Ministry of Education (MOE) Submitted/Accepted version X.W.L. acknowledges the funding support from the Ministry of Education of Singapore through the Academic Research Fund (AcRF)Tier-2 grant (MOE2019-T2-2-049).

Developing electrocatalytic energy conversion technologies for replacing the traditional energy source is highly expected to resolve the fossil fuel exhaustion and related environmental problems. Exploring stable and high-efficiency electrocatalysts is of vital importance for the promotion of these technologies. Single-atom catalysts (SACs), with atomically distributed active sites on supports, perform as emerging materials in catalysis and present promising prospects for a wide range of applications. The rationally designed near-range coordination environment, long-range electronic interaction and microenvironment of the coordination sphere cast huge influence on the reaction mechanism and related catalytic performance of SACs. In the current Review, some recent developments of atomically dispersed reactive centers for electrocatalytic CO2 reduction and water splitting are well summarized. The catalytic mechanism and the underlying structure-activity relationship are elaborated based on the recent progresses of various operando investigations. Finally, by highlighting the challenges and prospects for the development of single-atom catalysis, we hope to shed some light on the future research of SACs for the electrocatalytic energy conversion. Ministry of Education (MOE) National Research Foundation (NRF) Published version X.W.L. acknowledges the funding support from the Ministry of Education of Singapore through the Academic Research Fund (AcRF) Tier-2 grant (MOE2017-T2-2-003) and Tier1 grant (RG116/18), and the National Research Foundation (NRF) of Singapore via the NRF Investigatorship (NRFNRFI2016-04).

Perturbing the periodic electronic structure of the MoS2 basal plane via vacancy engineering offers an opportunity to explore its intrinsic activity. A significant challenge is the design of vacancy states, which include its type, distribution, and accessibility. Here, well-dispersed and vertically aligned MoS2 nanosheets with an in-plane selectively cleaved Mo-S bond on a carbon matrix (c-MoS2-C) have been prepared by a self-engaged strategy, which synergistically realizes uniform vacancy manufacturing and three-dimensional (3D) self-assembly of the defective MoS2 nanosheets. X-ray adsorption spectroscopy investigation confirms that the cleaved MoS2 basal plane generates newly active edge sites, where the Mo centers feature unsaturated coordination geometry. Theoretical calculations reveal that the exposed interior edge Mo sites represent new active centers for hydrogen adsorption/desorption. As expected, the synthesized c-MoS2-C exhibits markedly enhanced hydrogen evolution activity and superior stability. This in-plane activation strategy could be extended to other types of transition-metal dichalcogenides and catalytic reaction systems.

Soil microorganisms can be altered by plant invasion into wetland ecosystems and comprise an important linkage between phosphorus (P) availability and soil carbon (C) chemistry; however, the intrinsic mechanisms of P and C transformation associated with microbial community and function are poorly understood in coastal wetland. In this study, we used a sequential fractionation method and 13C nuclear magnetic resonance (NMR) spectroscopy to capture the changes in soil P pools and C chemical composition with bare flats (BF), native Phragmites australis(PA), and invasive Spartina alterniflora(SA), respectively. The responses of the soil microbial community using phospholipid fatty acid (PLFA) profiling and function indicated by nine enzyme activities associated with C, nitrogen (N), and P cycles were also investigated. Compared to PA and BF, SA invasion significantly (P < 0.05) changed P pools and mainly increased the available P by 17.5 and 37.0%, respectively. The presence of the plants (SA and PA) significantly (P < 0.05) altered the soil C chemical composition mainly by affecting the aliphatic functional groups, resulting in a lower alkyl C/O-alkyl C ratio value. Compared to BF and SA, PA significantly (P < 0.05) increased arbuscular mycorrhizal fungi (AMF) abundance. Soil enzyme activity, especially for the P and C cycle enzymes, was also affected by plant species with the highest geometric mean enzyme and hydrolase activity for the PA zone. We also found that soil C compositions and P pools were associated with microbial community structure and enzyme activity, respectively. However, little interaction between C and P was found on either soil microbial composition or soil enzyme activity variation. Further, microbial community composition was tightly correlated with the soil P compared to soil C chemistry, while enzyme activity showed more response with soil C chemistry compared to soil P pool changes.

Isolated cobalt atoms have been successfully decorated onto the surface of W18O49 ultrathin nanowires. The Co-atom-decorated W18O49 nanowires (W18O49@Co) greatly accelerate the charge carrier separ...

A pair of homochiral metal–organic frameworks are elaborated by employing flexible enantiopure ligands. They possess interesting double helical chains and rich hydrogen-bonding environment, exhibiting excellent chiral recognition ability to carvone.

Sustainable hydrogen fuel supply through electrochemical water splitting requires highly efficient, low-cost and robust electrocatalysts. Interface engineering is of key importance to improve the catalytic performance in a heterogeneous electrocatalytic system. Herein, a porous microcubic framework composed of a ZnO/ZnMoO4 heterostructure (ZnO@ZnMoO4) is prepared by a hybrid zeolitic imidazolate framework-derived oxidation method, and it shows much enhanced hydrogen evolution reaction (HER) activity in alkaline media. The overpotential (at 10 mA cm-2) for ZnO@ZnMoO4 is significantly reduced by 30% and 20% compared with those for virgin ZnO (v-ZnO) and polycrystalline zinc molybdenum oxide (PZMO), respectively. The enhanced electrocatalytic activity should be attributed to the ZnO/ZnMoO4 heterostructure, which can synergistically facilitate the charge transport. This work provides a more structured design strategy for electrocatalysts for future electrochemical energy conversion systems.

Mesoporous CoS/MoS2 with abundant heterogeneous interfaces was faciley synthesized from a bimetallic hybrid zeolitic imidazolate framework, which showed excellent catalytic activity and reaction kinetics in both the HER and OER in 1 M KOH. Meanwhile, as a cathode and anode in water splitting electrocatalysis, it delivers a low cell voltage of 1.61 V at 10 mA cm-2 and excellent durability.

Transition metal-based single-atom catalysts (TM-SACs) are promising alternatives to Au- and Ag-based electrocatalysts for CO production through CO 2 reduction reaction. However, developing TM-SACs with high activity and selectivity at low overpotentials is challenging. Herein, a novel Fe-based SAC with Si doping (Fe-N-C-Si) was prepared, which shows a record-high electrocatalytic performance toward the CO 2 -to-CO conversion with exceptional current density (>350.0 mA cm −2 ) and ~100% Faradaic efficiency (FE) at the overpotential of 2 battery delivers an outstanding performance with a maximal power density of 2.44 mW cm −2 at an output voltage of 0.30 V, as well as high cycling stability and FE (>90%) for CO production. Experimental combined with theoretical analysis unraveled that the nearby Si dopants in the form of Si-C/N bonds modulate the electronic structure of the atomic Fe sites in Fe-N-C-Si to markedly accelerate the key pathway involving *CO intermediate desorption, inhibiting the poisoning of the Fe sites under high CO coverage and thus boosting the CO 2 RR performance. This work provides an efficient strategy to tune the adsorption/desorption behaviors of intermediates on single-atom sites to improve their electrocatalytic performance.

The blue king crab, Paralithodes platypus, which belongs to the family Lithodidae, is a commercially and ecologically important species. However, a high‐quality reference genome for the king crab has not yet been reported. Here, we assembled the first chromosome‐level blue king crab genome, which contains 104 chromosomes and an N50 length of 51.15 Mb. Furthermore, we determined that the large genome size can be attributed to the insertion of long interspersed nuclear elements and long tandem repeats. Genome assembly assessment showed that 96.54% of the assembled transcripts could be aligned to the assembled genome. Phylogenetic analysis showed the blue king crab to have a close relationship with the Eubrachyura crabs, from which it diverged 272.5 million years ago. Population history analyses indicated that the effective population of the blue king crab declined sharply and then gradually increased from the Cretaceous and Neogene periods, respectively. Furthermore, gene families related to developmental pathways, steroid and thyroid hormone synthesis, and inflammatory regulation were expanded in the genome, suggesting that these genes contributed substantially to the environmental adaptation and unique body plan evolution of the blue king crab. The high‐quality reference genome reported here provides a solid molecular basis for further study of the blue king crab's development and environmental adaptation.

2D materials show many particular properties, such as high surface-to-volume ratio, high anisotropic degree, and adjustable chemical functionality. These unique properties in 2D materials have sparked immense interest due to their applications in photocatalytic systems, resulting in significantly enhanced light capture, charge-transfer kinetics, and surface reaction. Herein, the research progress in 2D photocatalysts based on varied compositions and functions, followed by specific surface modification strategies, is introduced. Fundamental principles focusing on light harvesting, charge separation, and molecular adsorption/activation in the 2D-material-based photocatalytic system are systemically explored. The examples described here detail the use of 2D materials in various photocatalytic energy-conversion systems, including water splitting, carbon dioxide reduction, nitrogen fixation, hydrogen peroxide production, and organic synthesis. Finally, by elaborating the challenges and possible solutions for developing these 2D materials, the review is expected to provide some inspiration for the future research of 2D materials used on efficient photocatalytic energy conversions.

Lateral motion estimation has been a challenge in ultrasound elastography mainly due to the low resolution, low sampling frequency, and lack of phase information in the lateral direction. Synthetic transmit aperture (STA) can achieve high resolution due to two-way focusing and can beamform high-density image lines for improved lateral motion estimation with the disadvantages of low signal-to-noise ratio (SNR) and limited penetration depth. In this study, Hadamard-encoded STA (Hadamard-STA) is proposed for the improvement of lateral motion estimation in elastography, and it is compared with STA and conventional focused wave (CFW) imaging. Simulations, phantom, and in vivo experiments were conducted to make the comparison. The normalized root mean square error (NRMSE) and the contrast-to-noise ratio (CNR) were calculated as the evaluation criteria in the simulations. The results show that, at a noise level of -10 dB and an applied strain of -1% (compression), Hadamard-STA decreases the NRMSEs of lateral displacements by 46.92% and 35.35%, decreases the NRMSEs of lateral strains by 52.34% and 39.75%, and increases the CNRs by 9.70 and 9.75 dB compared with STA and CFW, respectively. In the phantom experiments performed on a heterogeneous tissue-mimicking phantom, the sum of squared differences (SSD) between the reference and the motion-compensated RF data, and the CNR were calculated as the evaluation criteria. At an applied strain of -1.80%, Hadamard-STA is found to decrease the SSDs by 20.91% and 30.99% and increase the CNRs by 14.15 and 24.66 dB compared with STA and CFW, respectively. In the experiments performed on a breast phantom, Hadamard-STA achieves better visualization of the breast inclusion with a clearer boundary between the inclusion and the background than STA and CFW. The in vivo experiments were performed on a patient with a breast tumor, and the tumor could also be better visualized with a more homogeneous background in the strain image obtained by Hadamard-STA than by STA and CFW. These results demonstrate that Hadamard-STA achieves a substantial improvement in lateral motion estimation and maybe a competitive method for quasi-static elastography.

Single-atom catalysts (SACs), in which the metal active sites are isolated on the support and stabilized by coordinated atoms such as oxygen, nitrogen, sulfur, etc., represent the maximum usage efficiency of the metal atoms. Benefiting from the recent progress in synthetic strategies, characterization methods, and computational models, many SACs that deliver an impressive catalytic performance for a variety of reactions have been developed. The catalytic selectivity and activity are critical issues that need to be optimized and augmented in the areas of nanotechnology and biomedicine. This review summarizes some recent experimental and theoretical progress aimed at clarifying the structure of SACs and how they influence the catalytic performance. The examples described here elaborate on the utility of SACs and highlight the strengths of these catalysts in the applications of biomedicine, environmental protection, and energy conversion. Finally, some current challenges and future perspectives for SACs are also discussed., Some recent experimental and theoretical progress is summarized, aimed at clarifying the structure of single-atom catalysts and how they influence the catalytic performance.

The nuclear analysis of the toroidal field coil (TFC) has been performed using China Fusion Engineering Test Reactor (CFETR)-I model of 33.75-degree torus sector with a pitched Neutral Beam Interface port. A novel optimized global variance reduction (GVR) approach has been applied to Monte Carlo N-Particle Transport Code (MCNP) simulation process to improve parallel computing efficiency. The nuclear response in TFC includes the nuclear heat density, the integral nuclear heat, the absorbed dose, the fast neutron fluence and the total neutron fluence. Those data were calculated and compared with the International Thermonuclear Experimental Reactor (ITER) design limits. The results show that the fast neutron fluence, total neutron fluence and absorbed dose in some parts of inboard insulator exceed the ITER design limits, which means that more advanced shield materials should be used in radiation shielding design.

At the molecular level, metal coordinates are crucial for stabilizing an appropriate electronic configuration for high-efficiency oxygen reduction reaction (ORR) electrocatalysts. In this work, an excellent platform to realize the decoration of Fe coordinates at the subnanometer scale into nitrogen-doped carbon networks (designated as Fe–Fe@NC) is provided. X-ray absorption spectroscopy confirmed the precise configuration of Fe coordinates with Fe–Fe and Fe–N coordinations at the molecular level. As a cathode catalyst, the newly developed Fe–Fe@NC exhibited superior ORR performance and a higher peak power density of 175 mW cm−2 in Zn–air batteries. Unlike most reported pristine Fe-based catalysts, Fe–Fe@NC also showed good oxygen evolution reaction (OER) activity, with a low operating potential (1.67 V vs. RHE) at a current density of 10 mA cm−2. Calculations based on density functional theory revealed that the Fe–Fe coordination in Fe subclusters favored the 4e− transfer pathway and, thus, achieved highly active catalytic performance. This work reveals that iron clusters at the subnanometer scale provide an optimized electronic structure for enhanced ORR activity.

Rational design of efficient precious metal-free bifunctional electrocatalysis for the oxygen reduction and evolution reactions (ORR/OER) is highly demanded for practical applications in metal–air batteries. Herein, Co9S8 nanoparticles (NPs) encapsulated in nitrogen/sulfur dual-doped porous carbon nanofibers had been designed and synthesized by an electrospinning method with subsequent thermal annealing and denoted as Co9S8/NSC nanofibers. The as-prepared Co9S8/NSC nanofibers with high intrinsic activity and electrical conductivity exhibited excellent bifunctional oxygen electrocatalytic activity, with a half-wave potential of 0.84 V (vs. RHE) for the ORR and a potential of 1.56 V (vs. RHE) for the OER at 10 mA cm−2 current density. When Co9S8/NSC nanofibers were employed as an air electrode catalyst for rechargeable Zn–air batteries, a high energy density (997 W h kg−1), a low charge/discharge voltage gap, and an impressive long-term cycle stability (over 1000 cycles at 10 mA cm−2) were achieved.

Long non-coding RNAs (lncRNAs) regulate neurological damage in cerebral ischemia-reperfusion injury (CIRI). This study aimed to investigate the biological roles of lncRNA CEBPA-AS1 in CIRI. Middle cerebral artery occlusion and ischemia-reperfusion injury (MCAO/IR) rat model and oxygen-glucose deprivation and reoxygenation (OGD/R) cell lines were generated; the expression of CEBPA-AS1 was evaluated by qRT-PCR. The effects of CEBPA-AS1 on cell apoptosis and nerve damage were examined. The downstream microRNA (miRNA) and mRNA of CEBPA-AS1 were predicted and verified. We found that overexpression of CEBPA-AS1 could attenuate MCAO/IR-induced nerve damage and neuronal apoptosis in the rat model. Knockdown of CEBPA-AS1 aggravated cell apoptosis and enhanced the production of LDH and MDA in the OGD/R cells. Upon examining the molecular mechanisms, we found that CEBPA-AS1 stimulated APPL1 expression by combining with miR-340-5p, thereby regulating the APPL1/LKB1/AMPK pathway. In the rescue experiments, CEBPA-AS1 overexpression was found to attenuate OGD/R-induced cell apoptosis and MCAO/IR induced nerve damage, while miR-340-5p reversed these effects of CEBPA-AS1. In conclusion, CEBPA-AS1 could decrease CIRI by sponging miR-340-5, regulating the APPL1/LKB1/AMPK pathway.

OBJECTIVE Glioblastoma (GBM) expansion is accompanied by aberrant tumor vascularization. We demonstrated that the peptide hormone Apelin (APLN) controls GBM neo-vascularization and that the APLN-receptor antagonist Apelin-F13A improved the efficiency and reduced the invasive side effect of established antiangiogenic therapy. Here we investigated if Apelin-F13A blunts the formation of vasogenic edema, which can be monitored by MRI in vivo. METHODS To investigate the role of APLN -signaling in regulating the tightness of the tumor vasculature we performed in vivo leakage assays using Evans-Blue dye and fluorescent dextran. By confocal immunofluorescence, we characterized the maturation of the tumor vasculature with respect to pericyte-coverage and established a dynamic contrast enhanced (DCE) MR imaging protocol to follow vascular edema formation. RESULTS We found that Evans-Blue extravasation is significantly increased by 3-fold in APLNKO tumors compared to controls. Uptake of fluorescent Dextran by CD31+ endothelia was quantified and increased massively from 200μm2 per high magnification field (HMF) in wildtype to 3500μm2 per HMF in APLNKO tumors. Interestingly, intracerebral infusion of Apelin-F13A enhanced pericyte coverage of the tumor vasculature by 50%, decreased Evans-Blue extravasation from 25 μg/ml in controls to 8 μg/ml in treated tumors significantly and efficiently reversed the APLN-dependent vasogenic edema assessed by comparison of T2w-MRI to HE tumor volumes. To follow vasogenic edema formation in vivo, T1w 3D FLASH images were acquired every second over a 360s time course after gadolinium-based MR-contrast agent injection and demonstrated a delayed washout of the contrast in APLN-deficient GBM. CONCLUSION Together, our study shows that DCE-MRI can document APLN-dependent intratumoral vascular normalization and allows inspecting vasogenic edema formation in vivo. In addition to its anti-angiogenic / anti-invasive effect, Apelin-F13A can potently reduce vasogenic edema and might thus serve as a multimodal therapy for the treatment of human GBM in the future.

Lateral estimation has been a challenge in ultrasound elastography mainly due to the low resolution, low sampling frequency and lack of phase information in the lateral direction. Synthetic transmit aperture (STA) can achieve high resolution thanks to two-way focusing for improved lateral estimation, with the disadvantages of low signal-to-noise ratio (SNR) and limited penetration depth. In this study, we propose Hadamard-encoded STA (Hadamard-STA), which has been demonstrated to enhance the SNR of STA imaging, for improvement of strain estimation in elastography. Simulations and experiments were conducted on a heterogeneous model and an elasticity phantom with the same Young's modulus contrast. White Gaussian noise with different noise levels was added on the simulated channel dataset of Hadamard-STA to investigate its de-noising performance. The results show that Hadamard-STA outperforms STA with higher lateral and axial strain estimation qualities and may be a competitive method for quasi-static elastography.

Background: Ultrasound is one of the preferred choices for early screening of dense breast cancer. Clinically, doctors have to manually write the screening report, which is time-consuming and laborious, and it is easy to miss and miswrite. Aim: We proposed a new pipeline to automatically generate AI breast ultrasound screening reports based on ultrasound images, aiming to assist doctors in improving the efficiency of clinical screening and reducing repetitive report writing. Methods: AI efficiently generated personalized breast ultrasound screening preliminary reports, especially for benign and normal cases, which account for the majority. Doctors then make simple adjustments or corrections based on the preliminary AI report to generate the final report quickly. The approach has been trained and tested using a database of 4809 breast tumor instances. Results: Experimental results indicate that this pipeline improves doctors' work efficiency by up to 90%, greatly reducing repetitive work. Conclusion: Personalized report generation is more widely recognized by doctors in clinical practice than non-intelligent reports based on fixed templates or options to fill in the blanks.

Sustainable hydrogen fuel supply through electrochemical water splitting requires highly efficient, low-cost and robust electrocatalysts. Interface engineering is of key importance to improve the catalytic performance in a heterogeneous electrocatalytic system. Herein, a porous microcubic framework composed of a ZnO/ZnMoO

This paper analyzes the relevant contents of artificial intelligence (GAN), and combines the specific applications of GAN-based image technology in image repair processing, image expansion processing, image conversion processing, intelligent image analysis and content display immersion. Through research and application of deep learning technology, creative content, enrich the visual content, network optimization processing, development of intelligent technology and equipment, technology innovation and technology application, and its aim is to give full play to the artificial intelligence application video technology under the background of development advantages, promote the healthy development of industry economy.

Conductive metal-organic framework (MOF) materials have been recently considered as effective electrocatalysts. However, they usually suffer from two major drawbacks, poor electrochemical stability and low electrocatalytic activity in bulk form. Here, we have developed a rational strategy to fabricate a promising electrocatalyst composed of a nanoscale conductive copper-based MOF (Cu-MOF) layer fully supported over synergetic iron hydr(oxy)oxide [Fe(OH)x] nanoboxes. Owing to the highly exposed active centers, enhanced charge transfer, and robust hollow nanostructure, the obtained Fe(OH)x@Cu-MOF nanoboxes exhibit superior activity and stability for the electrocatalytic hydrogen evolution reaction (HER). Specifically, it needs an overpotential of 112 mV to reach a current density of 10 mA cm−2 with a small Tafel slope of 76 mV dec−1. X-ray absorption fine structure spectroscopy combined with density functional theory calculations unravels that the highly exposed coordinatively unsaturated Cu1-O2 centers could effectively accelerate the formation of key *H intermediates toward fast HER kinetics. Ministry of Education (MOE) National Research Foundation (NRF) Published version X.W.L. acknowledges the funding support from the Ministry of Education of Singapore through the Academic Research Fund (AcRF) Tier-2 funding (MOE2019-T2-2-049) and the National Research Foundation (NRF) of Singapore via the NRF Investigatorship (NRF-NRFI2016-04).

Species of the order Crocodylia are mostly large, predatory and semi-aquatic reptiles. Crocodylia, the closest living relatives of birds, first appeared in the Late Cretaceous period. In the present study, the complete mitochondrial (mt) genomes of 19 Crocodylia species, including two species (Melanosuchus niger and Caiman yacare) that have not been previously sequenced for mitogenomes, were processed through Illumina sequencing to offer genetic resources and compare with the mitogenomes of Crocodylia species reported previously. In addition, a high-resolution phylogenetic tree of nearly all current recognized species of Crocodylia is constructed based on mitogenomic data. Phylogenetic analyses support monophyly of three families: Alligatoridae (four genera: Alligator, Caiman, Melanosuchus and Paleosuchus), Crocodylidae (three genera: Crocodylus, Mecistops and Osteolaemus) and Gavialidae (two genera: Gavialis and Tomistoma). The tree topology is generally similar to previous studies. Molecular dating suggests that the first split within Crocodylia date back to the Upper Cretaceous (approx. 86.75 Mya). The estimated time to the most recent common ancestor (TMRCA) of Alligatoridae is 53.33 Mya and that of Crocodylidae and Gavialidae is 50.13 Mya, which might be closely linked to climate changes during the Late Palaeocene and Early Eocene. Additionally, this study proves that the diversification rate within Crocodylia began to increase from the Late Eocene (about 36 Mya) and two diversification peak periods of Crocodylia (0–10 Mya and 10–20 Mya) are disclosed, which is roughly consistent with the estimated crocodylian species richness through time. Combining all these clues, we can suggest that climate fluctuation may have played a decisive role in the speciation of Crocodylia.

Achieving a molecular level understanding of surface performance of nanomaterials by modulating the electronic structure is important but challenging. Here, we have developed a hollow microcube framework constructed by Mo-defect-rich ultrathin MoS2 nanosheets (HMF-MoS2) through a zeolite-like-framework-engaged strategy. The hollow structured HMF-MoS2 delivers an impressive specific capacity (384.3 mA h g-1 after 100 cycles at 100 mA g-1) and cycle stability (267 mA h g-1 after 125 cycles at 1 A g-1) for sodium storage. As evidenced by experiments and density functional theory calculations, abundant Mo vacancies in MoS2 can greatly accelerate the charge transfer and enhance the interaction between MoS2 and sodium, resulting in the promotion of sodium storage. Kinetic analysis result reveals that the ultrafast sodium ion storage of HMF-MoS2 could be associated with the significant contribution of capacitive energy storage. This work highlights the detailed molecular level understanding of chemical reaction on MoS2 surface by defect and morphology engineering, which can be applied to other metal sulfides for energy storage devices.

In this study, an analytical solution of stress, strain, and displacement, in the elastic and plastic zone is proposed. The solution is derived on the basis of ideal elastoplastic mechanical model of spherical salt cavern with shear dilatation behavior, by adopting Hoek-Brown (H-B) criterion. The solution obtains not only in small and large strain stage but also in creep stage. The proposed solution is validated, by comparison of the obtained results with numerical results in FLAC3D. The results indicate that the result obtained adopting the H-B criterion is closer to that one obtained adopting the Mohr-Coulomb (M-C). The H-B criterion is more applicable for the salt cavern construction as it considers the structural characteristics of the rock salt formation. The displacement difference obtained by two different methods decreases with the increase of GSI or running pressure, but it increases with the enlarged angle of dilation. The influence of different assumptions of elastic strain of plastic zone on displacements is more significant under large strain conditions. The influence of the angle of dilation on displacements is more obvious when the elastic strain of plastic zone is given to stationary values, and the influence degree increases with the enlarged angle of dilation. Under the same conditions, the creep displacement decreases with the increase of GSI, and both the creep displacement and the effect degree enhance with the enlarged dilation angle. The proposed solutions can be used in the stability analysis of surrounding rock in the construction and operation of salt cavern storage.

A coupled Alice–Bob modified Korteweg de-Vries (mKdV) system is established from the mKdV equation in this paper, which is nonlocal and suitable to model two-place entangled events. The Lax integra...

Efficient electrocatalysts are of great importance in improving the water splitting efficiency. Herein, we develop a self-templating strategy to construct porous iron cobalt (oxy)phosphide (Fe–Co–P) nanoboxes as promising pre-catalysts for the oxygen evolution reaction in alkaline solution. The constructed Fe–Co–P nanoboxes exhibit excellent electrocatalytic activity and afford a current density of 10 mA cm−2 at a small overpotential of 269 mV. Moreover, the structural evolution of the metal phosphides in the oxygen evolution process has been well monitored. X-ray absorption near-edge structure analyses and computational studies reveal that the structural merits and the effective intramolecular electronic coupling between the Fe and Co atoms via P/O bridges are responsible for the greatly improved electrocatalytic activity.

Perturbing the periodic electronic structure of the MoS

Non-noble-metal-based nanomaterials can exhibit extraordinary electrocatalytic performance toward the oxygen evolution reaction (OER) by harnessing the structural evolution during catalysis and the synergistic effect between elements. However, the structure of active centers in bimetallic/multimetallic catalysts is under long-time debate in the catalysis community. Here, an efficient bimetallic Ni-Fe selenide-derived OER electrocatalyst is reported and the structure-activity correlation during the OER evolution studied. By combining experiments and theoretical calculations, a conceptual advance is provided, in that the local coordination structure distortion and disordering of active sites inherited from the pre-catalyst and post-formed by a further reconstruction are responsible for boosting the OER performance. The active center is identified on Ni sites showing moderate bindings with oxygenous intermediates rather than Fe sites with strong and poisonous adsorptions. These findings provide crucial understanding in manipulating the local coordination and electronic structures toward rational design and fabrication of efficient OER electrocatalysts. Ministry of Education (MOE) Submitted/Accepted version X.W.L. acknowledges the funding support from the Ministry of Education of Singapore through the Academic Research Fund (AcRF) Tier-2 grant (MOE2019-T2-2-049). The National Science Fund for Distinguished Young Scholars (21825106) and the China Postdoctoral Science Foundation (2020M682333) are also acknowledged.