Heterogeneous Fe-Doped Ni(OH)2 Grown on Nickel Mesh by Electrodeposition for Efficient Alkaline Oxygen Evolution Reaction.

Designing highly excellent and stable catalysts for alkaline oxygen evolution reaction (OER) is gradually pivotal for clean energy development. In this work, a heterogeneous Fe-doped Ni(OH)2 (Ni/Fe-0.1) was developed via simple one-step electrodeposition onto nickel mesh. The heterogeneous interface structure generates sufficient active sites, significantly improving OER performance with an overpotential of 174 mV at 10 mA cm-2 (η10 ), while Tafel slope is only 43.0 mV dec-1 . In particular, Ni/Fe-0.1 is still able to operate stably at a current density of 1 A cm-2 for 100 h without obvious potential decay. The oxidation of Ni2+ to Ni3+ was detected by X-ray photoelectron spectroscopy, proving that the heterogeneous catalyst could stabilize the high-valence state of nickel as active sites to its superior OER performance. This work provides a convenient synthetic strategy for forming heterogeneous catalysts toward efficient water electrolysis.

Continual Learning of Generative Models With Limited Data: From Wasserstein-1 Barycenter to Adaptive Coalescence.

Learning generative models is challenging for a network edge node with limited data and computing power. Since tasks in similar environments share a model similarity, it is plausible to leverage pretrained generative models from other edge nodes. Appealing to optimal transport theory tailored toward Wasserstein-1 generative adversarial networks (WGANs), this study aims to develop a framework that systematically optimizes continual learning of generative models using local data at the edge node while exploiting adaptive coalescence of pretrained generative models. Specifically, by treating the knowledge transfer from other nodes as Wasserstein balls centered around their pretrained models, continual learning of generative models is cast as a constrained optimization problem, which is further reduced to a Wasserstein-1 barycenter problem. A two-stage approach is devised accordingly: 1) the barycenters among the pretrained models are computed offline, where displacement interpolation is used as the theoretic foundation for finding adaptive barycenters via a "recursive" WGAN configuration and 2) the barycenter computed offline is used as metamodel initialization for continual learning, and then, fast adaptation is carried out to find the generative model using the local samples at the target edge node. Finally, a weight ternarization method, based on joint optimization of weights and threshold for quantization, is developed to compress the generative model further. Extensive experimental studies corroborate the effectiveness of the proposed framework.

Doping rare earth cations with an additional chemical reduction synergistically weakened the photocatalytic performance of ceria.

Chemical reducing or rare earth cations (RE) doping was normally employed to promote the photocatalytic performance of ceria, aimed to evaluate their cooperation influences, ceria was obtained by decomposing homogenously RE (RE = La, Sm, and Y)-doped CeCO3OH in H2. XPS and EPR results evidenced that the excess oxygen vacancies (OVs) were formed in RE-doped CeO2 compared to the un-doped ceria. However, all the RE-doped ceria unexpectedly showed an impeded photocatalytic activity towards to methylene blue (MB) photodegradation. The 5% Sm-doped ceria had the best MB photodegradation ratio of 81.47% after 2-h reaction in all RE-doped samples, which was lower than that of 87.24% for the un-doped ceria. After doping RE cations and chemical reducing, the band gap of ceria were almost narrowed, while the PL spectra and photo-electro characterizations indicated that the separation efficiency of photo-excited e-/h+ (electrons/holes) was reduced. The RE dopants and formed excess OVs including inner and surface OVs was proposed to promote the recombination of e-/h+ which further hindered the generation of active species of ·O2- and ·OH, and finally weakened the photocatalytic activity of ceria.

LINC01116 Regulates the Proliferation and Apoptosis of Nucleus Pulposus Cells through miR-9-5p-mediated ZIC5 and the Wnt Pathway and Affects the Progression of Intervertebral Disc Degeneration.

OBJECTIVE: Intervertebral disc degeneration (IDD) represents one of the leading causes of low back pain. Research suggests the participation of LINC01116 in IDD progression. Herein, the current study explored the underlying mechanism of LINC01116 in IDD. METHODS: The differential expression patterns of LINC01116 in IDD and normal tissues were analyzed using the GEO database. Human nucleus pulposus (NP) cells were provided and treated with IL-1ß to establish IDD models in vitro. LINC01116 expression was detected and intervened. Indices such as cell proliferation, apoptosis, and extracellular matrix (ECM)-related factor expression were determined using CCK-8 assay, flow cytometry, and Western blotting. LINC01116 sublocation was identified by means of nuclear/cytosol fractionation assay. The binding relationships between LINC01116 and miR-9-5p and miR-9-5p and ZIC5 were verified by bioinformatics analysis, dual-luciferase assays, RNA immunoprecipitation (RIP) assay, and RNA-pull-down. Western blotting was conducted to measure the levels of the Wnt pathway key factors. RESULTS AND DISCUSSION: LINC01116 was highly expressed in the degenerative NP cells. Silencing of LINC01116 critically promoted degenerative NP cell proliferation and inhibited apoptosis and ECM loss. LINC01116 was located in the cytoplasm. In degenerative NP cell models, LINC01116 could competitively bind to miR-9-5p to elevate ZIC5 expression. LINC01116 induced NP cell apoptosis and impeded NP cell proliferation and ECM synthesis by inhibiting miR-9-5p and miR-9-5p targeted ZIC5. ZIC5 could effectively increase the levels of the Wnt pathway-related factors. CONCLUSION: Silencing LINC01116 blocked its adsorption of miR-9-5p as a sponge to promote the miR-9- 5p expression and inhibit ZIC5/Wnt activation, thus impacting NP cell biological functions.

Collaborative influence of morphology tuning and RE (La, Y, and Sm) doping on photocatalytic performance of nanoceria.

Tuning morphology and doping additional rare earth (RE) cations are potential techniques to promote the photocatalytic performance of ceria (CeO2), evaluating the collaborative effects of morphology and RE dopants is significant for producing high active ceria-based catalysts. So in this work, cubic, polyhedral and rod-like nanoceria doped with 10 mol % La (lanthanum), Y (yttrium), or Sm (samarium) were synthesized by a facile template-free hydrothermal method. Phases, morphologies, oxygen vacancies (OVs) concentration, energy band structure, photo-carriers separation/recombination, and photodegradation ratio toward methylene blue (MB) dye of as prepared ceria were studied. Results show that doped CeO2 maintains a similar morphology structure with un-doped sample and the band gap narrows slightly. Y-doped nanoceria, with an improved separation and a reduced recombination of photo-excited electrons (e-) and holes (h+), owns a higher MB photodegradation ratio than that of samples doping with La or Sm, which is measured as 79.04, 84.43, and 85.59% for Y-doped cubic, polyhedral, and rod-like CeO2. The collaborative influence of morphology tuning and RE (La, Y, and Sm) doping on photocatalytic performance of nanoceria includes the effects of doped elements and the formation of OVs. The elevation of OVs concentration as well as the separation efficiency of photo-generated e-/h+ are suggested to further enhance the photocatalytic performance of ceria.

MiR-98 Protects Nucleus Pulposus Cells against Apoptosis by Targeting TRAIL in Cervical Intervertebral Disc Degeneration.

The excessive apoptosis of nucleus pulposus (NP) cells is a major risk factor in the progress of cervical intervertebral disc degeneration (IVDD). In this study, we investigated the impact of miR-98 on apoptosis of NP cells and the potential molecular mechanisms. Lipopolysaccharide (LPS) was used to establish an NP cell IVDD model. The sponging effect of miR-98 on TRAIL 3'UTR was predicted by ENCORI and assessed by the dual-luciferase reporter gene system. The expression levels of miR-98, TRAIL, and TRAIL pathway-related genes were tested by qRT-PCR, Western blot, and immunofluorescence analysis. Cell apoptosis was analyzed by Hoechst 33258 staining and flow cytometry. Cell viability was analyzed by MTT assay. It was found that the expression level of miR-98 was downregulated, while the level of TRAIL was upregulated in IVDD tissues, and their levels were negatively and positively associated with the clinical MRI grade, respectively. The LPS treatment resulted in a significant decrease of the miR-98 expression level and an increase of the TRAIL expression level in NP cells. miR-98 reduced NP cell apoptosis under LPS treatment in vitro. miR-98 directly targeted TRAIL. Moreover, the mRNA and protein levels of DR5, FADD, cleaved caspase8, cleaved caspase3, and cleaved PARP were downregulated by miR-98 overexpression. Overexpression of TRAIL partially reversed the suppressive roles of miR-98 on cell apoptosis and activation of the TRAIL pathway. We concluded that miR-98 inhibited apoptosis of NP cells by inactivating the TRAIL pathway via targeting TRAIL in IVDD NP cells. These results indicated that miR-98 might be a therapeutic target for IVDD.

High-Frequency 0.36BiScO3-0.64PbTiO3 Ultrasonic Transducer for High-Temperature Imaging Application.

( 1- x )BiScO3- x PbTiO3 (BS-PT) ceramics have excellent piezoelectricity and high Curie temperature at its morphotropic phase boundary (MPB) ( x = 0.64 ), so it is a promising piezoelectric material for fabricating high-temperature ultrasonic transducer (HTUT). Electric properties of 0.36BS-0.64PT ceramics were characterized at different temperatures, and an HTUT with the center frequency of about 15 MHz was designed by PiezoCAD based on the measuring results. The prepared HTUT was tested in a silicone oil bath at different temperatures systematically. The test results show that the HTUT can maintain a stable electrical resonance until 290 °C and get a clear echo response until 250 °C with slight changes of the center frequency. Then, a stepped metal block submerged in silicone oil was imaged by the HTUT until 250 °C. Velocity of silicone oil and axial resolution of the HTUT at different temperatures was calculated. The results verify the capability of 0.36BS-0.64PT-based HTUT for high-temperature ultrasonic imaging applications.

Insight into the Contributions of Surface Oxygen Vacancies on the Promoted Photocatalytic Property of Nanoceria.

Oxygen vacancies (OVs) have critical effects on the photoelectric characterizations and photocatalytic activity of nanoceria, but the contributions of surface OVs on the promoted photocatalytic properties are not clear yet. In this work, we synthesized ceria nanopolyhedron (P-CeO2), ceria nanocube (C-CeO2) and ceria nanorod (R-CeO2), respectively, and annealed them at 600 °C in air, 30%, 60% or pure H2. After annealing, the surface OVs concentration of ceria elevates with the rising of H2 concentration. Photocatalytic activity of annealed ceria is promoted with the increasing of surface OVs, the methylene blue photodegradation ratio with pure hydrogen annealed of P-CeO2, C-CeO2 or R-CeO2 is 93.82%, 85.15% and 90.09%, respectively. Band gap of annealed ceria expands first and then tends to narrow slightly with the rising of surface OVs, while the valence band (VB) and conductive band (CB) of annealed ceria changed slightly. Both of photoluminescence spectra and photocurrent results indicate that the separation efficiency of photoinduced electron-hole pairs is significantly enhanced with the increasing of the surface OVs concentration. The notable weakened recombination of photogenerated carrier is suggested to attribute a momentous contribution on the enhanced photocatalytic activity of ceria which contains surface OVs.

Lead-Free KNN-Based Textured Ceramics for High-Frequency Ultrasonic Transducer Application.

Environment-friendly lead-free piezoelectric materials with excellent piezoelectric properties are needed for high-frequency ultrasonic transducer applications. Recently, lead-free 0.915(K0.45Na0.5Li0.05)NbO3-0.075BaZrO 3-0.01(Bi0.5Na0.5)TiO3 (KNLN-BZ-BNT) textured piezo- electric ceramics have high piezoelectric response, superior thermal stability, and excellent fatigue resistance, which are promising for devices applications. In this work, the KNLN-BZ-BNT textured ceramics were prepared by the tape-casting method. Microstructural morphology, phase transition, and electrical properties of KNLN-BZ-BNT textured ceramics were investigated. High-frequency needle-type ultrasonic transducers were designed and fabricated with these textured ceramics. The tightly focused transducers have a center frequency higher than 80 MHz and a -6-dB fractional bandwidth of 52%. Such transducers were built for an f -number close to 1, and the desired focal depth was achieved by press-focusing technology associated with a set of customer design fixture. Its lateral resolution was better than [Formula: see text] by scanning a 15- [Formula: see text] tungsten wire target. These promising results demonstrate that the lead-free KNLN-BZ-BNT textured ceramic is a good candidate for high-frequency ultrasonic transducer applications.

Effects of Inonotus obliquus Polysaccharides on Proliferation, Invasion, Migration, and Apoptosis of Osteosarcoma Cells.

OBJECTIVES: To observe the effect of Inonotus obliquus polysaccharide (IOP) on the proliferation, invasion, migration, and apoptosis of osteosarcoma cells and to elucidate its underlying molecular mechanism. METHODS: IOP was extracted from Inonotus obliquus, human osteosarcoma MG-63 cells and U2OS cells were cultured in vitro, and the effects of IOP on the proliferation, migration, invasion, and apoptosis of MG-63 cells and U2OS cells were determined by CCK-8 assays, cell scratch assays, transwell assays, and flow cytometry, respectively. Western blot was used to detect the expression of related proteins in the Akt/mTOR and NF-κB signaling pathways. RESULTS: Compared with the control group, MG-63 cells and U2OS cells treated with IOP of 80 µg/ml, 160 µg/ml, and 320 µ g/ml in the experimental group had significantly lower proliferation activity, decreased migration and invasion ability, and increased apoptosis rate (P < 0.05). Furthermore, IOP could significantly inhibit the activation of the Akt/mTOR and NF-κB signaling pathway (P < 0.05). CONCLUSION: IOP can regulate the proliferation, migration, invasion, and apoptosis of osteosarcoma cells by inhibiting the activation of the Akt/mTOR signaling pathway. It has antitumor activity on osteosarcoma and has the potential of clinical application in osteosarcoma treatment.

A tensor-based framework for studying eigenvector multicentrality in multilayer networks.

Centrality is widely recognized as one of the most critical measures to provide insight into the structure and function of complex networks. While various centrality measures have been proposed for single-layer networks, a general framework for studying centrality in multilayer networks (i.e., multicentrality) is still lacking. In this study, a tensor-based framework is introduced to study eigenvector multicentrality, which enables the quantification of the impact of interlayer influence on multicentrality, providing a systematic way to describe how multicentrality propagates across different layers. This framework can leverage prior knowledge about the interplay among layers to better characterize multicentrality for varying scenarios. Two interesting cases are presented to illustrate how to model multilayer influence by choosing appropriate functions of interlayer influence and design algorithms to calculate eigenvector multicentrality. This framework is applied to analyze several empirical multilayer networks, and the results corroborate that it can quantify the influence among layers and multicentrality of nodes effectively.

Fabrication and Characterization of High-Frequency Ultrasound Transducers Based on Lead-Free BNT-BT Tape-Casting Thick Film.

A lead-free 0.94(Na0.5Bi0.5) TiO3-0.06 BaTiO3 (BNT-BT) thick film, with a thickness of 60 µm, has been fabricated using a tape-casting method. The longitudinal piezoelectric constant, clamped dielectric permittivity constant, remnant polarization and coercive field of the BNT-BT thick film were measured to be 150 pC/N, 1928, 13.6 µC/cm², and 33.6 kV/cm, respectively. The electromechanical coupling coefficient kt was calculated to be 0.55 according to the measured electrical impedance spectrum. A high-frequency plane ultrasound transducer was successfully fabricated using a BNT-BT thick film. The performance of the transducer was characterized and evaluated by the pulse-echo testing and wire phantom imaging operations. The BNT-BT thick film transducer exhibits a center frequency of 34 MHz, a -6 dB bandwidth of 26%, an axial resolution of 77 µm and a lateral resolution of 484 µm. The results suggest that lead-free BNT-BT thick film fabricated by tape-casting method is a promising lead-free candidate for high-frequency ultrasonic transducer applications.

Critical behavior of blind spots in sensor networks.

Blind spots in sensor networks, i.e., individual nodes or small groups of nodes isolated from the rest of the network, are of great concern as they may significantly degrade the network's ability to collect and process information. As the operations of many types of sensors in realistic applications rely on short-lifetime power supplies (e.g., batteries), once they are used up ("off"), replacements become necessary ("on"). This off-and-on process can lead to blind spots. An issue of both theoretical and practical interest concerns the dynamical process and the critical behavior associated with the occurrence of blind spots. In particular, there can be various network topologies, and the off-and-on process can be characterized by the probability that a node functions normally, or the occupying probability of a node in the network. The question to be addressed in this paper concerns how the dynamics of blind spots depend on the network topology and on the occupying probability. For regular, random, and mixed networks, we provide theoretical formulas relating the probability of blind spots to the occupying probability, from which the critical point for the occurrence of blind spots can be determined. For scale-free networks, we present a procedure to estimate the critical point. While our theoretical and numerical analyses are presented in the framework of sensor networks, we expect our results to be generally applicable to network partitioning issues in other networks, such as the wireless cellular network, the Internet, or transportation networks, where the issue of blind spots may be of concern.

Percolation and blind spots in complex networks.

Recent works on network security have focused on whether a complex network can maintain its integrability under attack or random node failures. In applications of increasing importance such as sensor networks, a somewhat different problem, namely, the occurrence of isolated nodes (or blind spots), is of great interest. We show that, for networks with a stronger ability to form global spanning clusters, it is relatively more difficult to eliminate blind spots, and vice versa. We use the framework of percolation to investigate this phenomenon. Our analysis also yields a formula for the average number of blind spots, which provide an explanation for several numerical findings.

Force-dependent stepping kinetics of myosin-V.

Myosin-V is a processive two-headed actin-based motor protein involved in many intracellular transport processes. A key question for understanding myosin-V function and the communication between its two heads is its behavior under load. Since in vivo myosin-V colocalizes with other much stronger motors like kinesins, its behavior under superstall forces is especially relevant. We used optical tweezers with a long-range force feedback to study myosin-V motion under controlled external forward and backward loads over its full run length. We find the mean step size remains constant at approximately 36 nm over a wide range of forces from 5 pN forward to 1.5 pN backward load. We also find two force-dependent transitions in the chemomechanical cycle. The slower ADP-release is rate limiting at low loads and depends only weakly on force. The faster rate depends more strongly on force. The stronger force dependence suggests this rate represents the diffusive search of the leading head for its binding site. In contrast to kinesin motors, myosin-V's run length is essentially independent of force between 5 pN of forward to 1.5 pN of backward load. At superstall forces of 5 pN, we observe continuous backward stepping of myosin-V, indicating that a force-driven reversal of the power stroke is possible.