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Accurate human pose estimation is crucial for precisely locating key points of human body during the near-electricity work in substations. However， traditional detection methods often suffer from low accuracy， missed detections， and misdetections due to occlusion by limb or equipment. To address these challenges， the paper proposes a high-precision multi-human body pose estimation method tailored for near-electricity work in substations. First， a deformable convolutional network （DCN） is embedded into the backbone network， enabling the model to autonomously learn human joint features and enhancing its geometric modeling capabilities. Second， a feature pyramid network is constructed based on the ConvNeXt v2 Block as the neck structure. This strengthens feature interaction learning through cross-scale connections. In the prediction head， the coordinate attention （CA） mechanism is introduced to further capture channel and spatial information of feature maps. Finally， by improving the original loss function， the model’s convergence speed is accelerated. The results show that， compared to the baseline model， the proposed model’s average detection accuracies P0.50， P0.75， and P have increased by 2.7%， 7.3%， and 4.2%， respectively. This provides significant technical support for the safety of near-electricity workers in complex substation environments.

Objective To conduct a network meta-analysis on the effectiveness of first-line immunotherapy on patients with brain metastases from advanced non-small cell lung cancer (NSCLC). Methods Two investigators conducted a computerized search of Pubmed, Embase, Cochrane, and other databases to screen the literature, extract the information, and assess the risk of bias of the included studies. The included clinical trials were statistically analyzed using R (4.1.3) software. For the study outcome indicators OS and PFS, the risk ratios (HRs), and the 95% confidence intervals (CIs) were extracted from the included studies and logarithmically transformed into effect analysis statistics. Results Six randomized controlled trials were finally included, including 327 patients with non-excludable NSCLC brain metastases. Network meta-analysis suggested that PD-1 inhibitor + CTLA-4 was more advantageous than the conventional chemotherapy for enhancing patients’ OS (HR: 0.13, 95%CI: 0.03-0.71), followed by PD-L1 inhibitor (HR: 0.17, 95%CI: 0.04-0.74) and PD-1 inhibitor + chemotherapy (HR: 0.36, 95%CI: 0.2-0.63). PD-1 inhibitor + CTLA-4 was also more advantageous (HR: 0.37, 95%CI: 0.15-0.93) than the conventional chemotherapy for boosting patients’ PFS, followed by PD-L1 inhibitor + chemotherapy (HR: 0.44, 95%CI: 0.29-0.66) and PD-1 inhibitor (HR: 0.48, 95%CI: 0.27-0.86). Conclusion Immune checkpoint inhibitor therapy improves the survival of patients with brain metastases from advanced NSCLC. In particular, the combination of PD-1 inhibitor and CTLA-4 inhibitor show excellent survival benefit.

Aim: To systematically search, evaluate and synthesise the most robust evidence regarding pressure injury prevention in orthopaedic patients admitted to general wards. Design: The present study provides an evidence‐based summary of the most robust findings, adhering to the evidence guidelines established by the Center for Evidence‐Based Nursing of Fudan University. Method: According to the "6S" model, a systematic search was conducted for literature on pressure injury prevention among orthopaedic patients in general wards. The types of literature included guidelines, clinical decisions, expert Consensus, evidence summaries, etc. The search period covered the time from the beginning of the database up to December 2023. Data Source s : The following databases and resources were systematically searched: Up To Date, JBI, NICE, WOCN, NZWCS, etc. Results: Fifteen literature sources were included, comprising one clinical decision, eight guidelines, one systematic review, and one expert Consensus. In these sources, a comprehensive collection of 34 pieces of best evidence was formed across six key topics: risk assessment, position management, skin care, device used for device‐related pressure injury, nutritional assessment, and support, as well as health education and training. Among the evidence gathered, a strong recommendation was made for 18 pieces, while the remaining 16 received a weak recommendation. Conclusion: This study provides a comprehensive synthesis of the most robust evidence on pressure injury prevention in orthopaedic patients, encompassing 34 pieces of evidence that can serve as valuable references for clinical practice. Before implementing this evidence, it is crucial to evaluate the specific contextual factors within different countries and medical institutions, as well as the facilitators and barriers influencing its application by healthcare professionals and patient's preferences. Furthermore, targeted evidence selection should be conducted through careful screening and subsequent adjustments in implementation, thereby offering a more scientifically grounded basis for clinical nursing practice. Future research endeavours should prioritise investigating strategies for effective evidence utilisation. Implications for the Profession and Patient Care: The prevention of pressure injuries poses a significant challenge for orthopaedic patients. This study presents a synthesis of 34 pieces of best evidence to provide guidance on preventive measures for pressure injuries in orthopaedic patients. Adhering to and implementing these 34 pieces of evidence can effectively aid in preventing pressure injuries in clinical practice. This evidence encompasses risk assessment, position management, skin care, device usage for device‐related pressure injuries, nutritional support and evaluation, and health education and training, establishing a comprehensive and systematic implementation process. Assessing the risk of pressure injuries during interventions serves as an essential prerequisite for developing effective strategies to prevent such injuries among orthopaedic patients. Ultimately, this study will offer valuable guidance to healthcare professionals worldwide regarding preventing pressure injuries in orthopaedic patients. Impact: Upon admission to the hospital, it is essential to conduct a risk assessment and implement evidence‐based, individualised prevention measures for pressure ulcers in patients to prevent their occurrence. This study will provide valuable insights into preventing pressure injuries in orthopaedic patients admitted to orthopaedic wards for healthcare workers worldwide. State: The PRIMA manifest is utilised during the text preparation process. Trail Registration: ES20245365 [ABSTRACT FROM AUTHOR]

In this paper, an efficient mask optimization method for enhanced digital micromirror device lithography quality based on improved particle swarm optimization (PSO) is proposed, which greatly improves the quality of lithography. First, the traditional PSO algorithm is improved by introducing adaptive parameter adjustment to enhance its search ability in complex problems. In addition, in order to avoid premature convergence of the algorithm, a simulated annealing operation is introduced to make it accept the different solution with a certain probability and jump out of the local optimal better. The numerical simulation experiment results showed that the pattern errors between the print image and target pattern were reduced by 93.5%, 95.8%, and 95.6%, respectively. Compared with traditional optimization methods, the proposed algorithm significantly improves the image quality, especially in the aspects of edge contour and pattern fidelity. [ABSTRACT FROM AUTHOR]

Nature performs critical physiological functions using a series of structurally and functionally diverse membrane proteins embedded in cell membranes, in which native ion protein channels modify the electrical potential inside and outside the cell membrane through charged ion movements. Consequently, the cell responds to external stimuli, playing an essential role in various life activities, such as nerve excitation conduction, neurotransmitter release, muscle movement, and control of cell differentiation. Supramolecular artificial channels, which mimic native protein channels in structure and function, adopt unimolecular or self‐assembled structures, such as crown ethers, cyclodextrins, cucurbiturils, column arenes, cyclic peptide nanotubes, and metal‐organic artificial channels, in channel construction strategies. Owing to the various driving forces involved, artificial synthetic ion channels can be divided into artificial cation and anion channels in terms of ion selectivity. Cation selectivity usually originates from ion coordination, whereas anion selectivity is related to hydrogen bonding, ion pairing, and anion‐dipole interactions. Several studies have been conducted on artificial cation channels, and several reviews have summarized them in detail; however, the research on anions is still in the initial stages, and related reviews have rarely been reported. Hence, this article primarily focuses on the recent research on anion channels. [ABSTRACT FROM AUTHOR]

Tunnel-boring machines (TBMs) are widely used in urban underground tunnel construction due to their fast and efficient features. However, shield-tunnel construction faces increasingly complex geological environments and may encounter geological hazards such as faults, fracture zones, water surges, and collapses, which can cause significant property damage and casualties. Existing geophysical methods are subject to many limitations in the shield-tunnel environment, where the detection space is extremely small, and a variety of advanced detection methods are unable to meet the required detection requirements. Therefore, it is crucial to accurately detect the geological conditions in front of the tunnel face in real time during the tunnel boring process of TBM tunnels. In this paper, a 3D-ERT advanced detection method using source-position electrode excitation is proposed. First, a source-position electrode array integrated into the TBM cutterhead is designed for the shield-tunnel construction environment, which provides data security for the inverse imaging of the anomalous bodies. Secondly, a 3D finite element tunnel model containing high- and low-resistance anomalous bodies is established, and the GREIT reconstruction algorithm is utilized to reconstruct 3D images of the anomalous body in front of the tunnel face. Finally, a physical simulation experiment platform is built, and the effectiveness of the method is verified by laboratory physical modeling experiments with two different anomalous bodies. The results show that the position and shape of the anomalous body in front of the tunnel face can be well reconstructed, and the method provides a new idea for the continuous detection of shield construction tunnels with boring. [ABSTRACT FROM AUTHOR]

Metalenses have provided a good solution to the bulkiness of conventional refractive lenses. Due to the subwavelength feature sizes of the metalens structure, the increasing fabrication difficulties at high frequencies limit its application in the terahertz and optical regime. Moreover, the deeply subwavelength features of the metasurface unit cells usually make the cells strongly resonant, which limits the bandwidth of the metalens. In this paper the usage of aggressive discretization in a metalens design is investigated, and it is found that aggressive discretization can lead to the usage of weakly resonant and relatively large unit cells, which leads to excellent broadband performance and dramatically relaxes the feature size tolerance of the metalens. For examples, two terahertz focusing metalenses are designed which feature large numerical apertures (NA = 0.86), diffraction‐limited focusing over a broad bandwidth (240–400 GHz, or 50% bandwidth), and minimum feature sizes of 0.1 mm. These tolerance‐relaxed terahertz metalenses are successfully constructed using conventional printed‐circuit‐board fabrication technology. The experimental measurements validate the simulated performances. Compared to existing terahertz meta‐devices based on micro‐fabrication or nano‐fabrication technologies, this paper opens door to a kind of high‐quality terahertz metasurfaces featuring low‐cost, rapid, and established fabrication. [ABSTRACT FROM AUTHOR]

As a planarization technique, chemical mechanical polishing (CMP) continues to suffer from pattern effects that result in large variations in material thickness, which can influence circuit performance and yield. Therefore, tools for predicting post-CMP chip morphology based on the layout-dependent effect (LDE) have become increasingly critical and widely utilized for design verification and manufacturing development. In order to characterize the impact of patterns on polishing, such models often require the extraction of graphic parameters. However, existing extraction algorithms provide a limited description of the interaction effect between layout patterns. To address this problem, we calculate the average density as a density correction and innovatively use a one-dimensional line contact deformation profile as a weighting function. To verify our hypothesis, the density correction method is applied to a density step-height-based high-K metal gate-CMP prediction model. The surface prediction results before and after optimization are compared with the silicon data. The results show a reduction in mean squared error (MSE) of 40.1% and 35.2% in oxide and Al height predictions, respectively, compared with the preoptimization results, confirming that the optimization method can improve the prediction accuracy of the model. [ABSTRACT FROM AUTHOR]

gem‐Dibromoalkanes are important synthetic building block in organic chemistry, but their preparation is still troublesome. Herein, we have developed a simple and practical protocol for the synthesis of gem‐dibromoalkanes from aldehydes using tetrabutylammonium tribromide and triphenyl phosphite. A variety of alkyl and aromatic aldehydes can be transformed into the corresponding products within 10 minutes. This protocol is also applicable to alcohols, and the configuration of chiral alcohol is inverted during the process with excellent enantiopurity. [ABSTRACT FROM AUTHOR]

Sympiezomias velatus (Chevrolat) (Coleoptera: Curculionidae) has caused serious damage on jujube trees (Ziziphus jujuba Mill) in northern China. Semiochemicals emerging from the host are essential in the process of insects identifying and localizing the host. The highly expressed odorant-binding protein 1 of S. velatus (SvelOBP1) was assumed to play a possible role in the recognition of host volatiles. In this study, SvelOBP1 was cloned based on the antennal transcriptome of S. velatus. The recombinant SvelOBP1 protein was expressed in Escherichia coli and purified by Ni-NTA resin. The predicted protein SvelOBP1 belonged to a classic OBP subfamily. The expression patterns revealed that SvelOBP1 was mainly expressed in the antennae of both males and females, whereas the expression of SvelOBP1 in other body parts could be neglected. The fluorescence binding assay indicated that SvelOBP1 displayed very strong binding affinities to dibutyl benzene-1,2-dicarboxylate and (Z)-hex-3-en-1-ol (Ki = 6.66 ± 0.03 and 7.98 ± 0.06 μM). The molecular docking results showed that residues Trp114, Phe115 and Asp110 may be involved in binding to both dibutyl benzene-1,2-dicarboxylate and (Z)-hex-3-en-1-ol and may have a great impact on odorant recognition of S. velatus. Our results provide evidence that SvelOBP1 might participate in the olfactory molecular perception of S. velatus and would promote the development of pest attractants for S. velatus control. [ABSTRACT FROM AUTHOR]

Microgroove structures with helical pitches in a wavelength level are increasingly required in optical areas. However, conventional manufacturing techniques generate relatively high stresses during pressing, resulting in poor precision when forming microgrooves. This paper reports on the mechanism of the ultrasonic vibration-assisted microgroove forming of precise hot-pressed optical glass. A finite element (FE) thermocompression model of the viscoelastic material was developed and the entire forming process was numerically simulated using coupled thermal-structural analysis. The analysis of several process parameters was carried out using orthogonal experiments, from which the optimum combination of parameters was selected. The glass thermoforming process is also assisted by ultrasonic vibration. The thermal and mechanical effects of vibration improved material flow and optimized forming results. The average maximum stress in the glass during the forming process was only 3.04 × 10−3 Mpa, while the maximum stress in the hot-pressing stage without ultrasound was 1.648 Mpa. The stress results showed that the material-forming stress is significantly reduced. [ABSTRACT FROM AUTHOR]

In advanced integrated circuit manufacturing processes, the quality of chemical mechanical flattening is a key factor affecting chip performance and yield. Therefore, it has become increasingly important to develop an accurate predictive model for the chip surface topography after chemical mechanical flattening. In the modeling process, the noise problem of atomic force microscopy measurement data is relatively serious. To solve this problem, the noise characteristics of atomic force microscope measurement data for chip surface topography in this field are studied and discussed in this paper. It is found that the noise present in such problems is mainly triggered by the vibration and tilt of the probe. Two types of noise, low-frequency and high-frequency, are presented in the time domain. In order to solve the noise problem in this modeling data, this paper analyzes the spectral characteristics of the measurement data using Fourier transform, and a wavelet-Fourier transform composite noise reduction process is proposed. The algorithm is applied to the noise reduction of the chip surface data of 32 nm copper interconnect process. The noise reduction results were compared with scanning electron microscope photographs to verify the effectiveness of the noise reduction. [ABSTRACT FROM AUTHOR]

Integrated Energy Systems (IES) are an important way to improve the efficiency of energy, promote closer connections between various energy systems, and reduce carbon emissions. The transformation between electricity, heating, and cooling loads into each other makes the dynamic characteristics of multiple loads more complex and brings challenges to the accurate forecasting of multi-energy loads. In order to further improve the accuracy of IES short-term load forecasting, we propose the Convolutional Neural Network, the Long Short-Term Memory Network, and Auto-Regression (CLSTM-AR) combined with the multi-dimensional feature fusion (MFFCLA). In detail, CLSTM can extract the coupling and periodic characteristics implied in IES load data from multiple time dimensions. AR takes load data as the input to extract features of sequential auto-correlation over adjacent time periods. Then, the diverse and effective features extracted by CLSTM, LSTM, and AR can be fused using the multi-dimensional feature fusion technique. Ultimately, the model achieves the accurate prediction of multiple loads. In conclusion, compared with other forecasting models, the case study results show that MFFCLA has higher forecasting precision compared with the comparable model in the short-term multi-energy load forecasting performance of electricity, heating, and cooling. The accuracy of MFFCLA can help to optimize and dispatch IES to make better use of renewable energy. [ABSTRACT FROM AUTHOR]

Bone cement is a crucial material to treat bone metastases defects, and can fill the bone defect and provide mechanical support simultaneously, but the antitumor effect is very limited. Magnetic bone cement not only supports bone metastasis defects but can also achieve magnetic hyperthermia to eliminate tumor cells around the bone defect. However, the physicochemical properties of the bone cement matrix will change if the weight ratio of the magnetic nanoparticles in the cement is too high. We mixed 1 weight percent Zn0.3Fe2.7O4 with good biocompatibility and high heating efficiency into a polymethyl methacrylate matrix to prepare magnetic bone cement, which minimized the affection for physicochemical properties and satisfied the hyperthermia requirement of the alternating magnetic field. [ABSTRACT FROM AUTHOR]

Magnesium potassium phosphate cement (MKPC) has attracted considerable attention as a bone regeneration material. However, there are only a few reports on its biomechanical properties. To evaluate the biomechanical properties of MKPC, we compared the mechanical parameters of pedicle screws enhanced with either MKPC or polymethyl methacrylate (PMMA) bone cement. The results show that the maximum pull-out force of the pedicle screws was 417.86 ± 55.57 and 444.43 ± 19.89 N after MKPC cement setting for 30 min and 12 h, respectively, which was better than that of the PMMA cement. In fatigue tests, the maximum pull-out force of the MKPC cement group was 435.20 ± 7.96 N, whereas that of the PMMA cement in the control group was 346.80 ± 7.66 N. Furthermore, the structural characterization analysis of the MKPC cement revealed that its microstructure after solidification was an irregular tightly packed crystal, which improved the mechanical strength of the cement. The maximum exothermic temperature of the MKPC reaction was 45.55 ± 1.35 °C, the coagulation time was 7.89 ± 0.37 min, and the compressive strength was 48.29 ± 4.76 MPa, all of which meet the requirements of clinical application. In addition, the MKPC cement did not significantly inhibit cell proliferation or increase apoptosis, thus indicating good biocompatibility. In summary, MKPC exhibited good biomechanical properties, high initial strength, good biocompatibility, and low exothermic reaction temperature, demonstrating an excellent application potential in the field of orthopedics. [ABSTRACT FROM AUTHOR]

Purpose. To evaluate the biomechanics of a novel fusion strategy (hybrid internal fixation+horizontal cage position) in minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF). Methods. MIS-TLIF finite element models for three fusion strategies were created based on computed tomography images, namely, Model-A, hybrid internal fixation (ipsilateral pedicle screw and contralateral translaminar facet screw fixation)+horizontal cage position; Model-B, bilateral pedicle screw (BPS) fixation+horizontal cage position; and Model-C, BPS fixation+oblique 45° cage position. A preload of 500 N and a moment of 10 Nm were applied to the models to simulate lumbar motion, and the models' range of motion (ROM), peak stress of the internal fixation system, and cage were assessed. Results. The ROM for Models A, B, and C were not different (P > 0.05) but were significantly lower than the ROM of Model-INT (P < 0.0001). Although there were subtle differences in the ROM ratio for Models A, B, and C, the trend was similar. The peak stress of the internal fixation system was significantly higher in Model-A than that of Models B and C, but only the difference between Models A and B was significant (P < 0.05). The peak stress of the cage in Model-A was significantly lower than that of Models B and C (P < 0.01). Conclusion. Hybrid internal fixation with horizontal single cage implantation can provide the same biomechanical stability as traditional fixation while reducing peak stress on the cage and vertebral endplate. [ABSTRACT FROM AUTHOR]

Odorant binding proteins (OBPs) play an important role in insect olfaction. The jujube bud weevil Pachyrhinus yasumatsui (Coleoptera: Curculionidae) is a major pest of Zizyphus jujuba in northern China. In the present study, based on the antennal transcriptome, an OBP gene of P. yasumatsui (PyasOBP2) was cloned by reverse transcription PCR (RT-PCR). Expression profile analyses by quantitative real-time PCR (qRT-PCR) revealed that PyasOBP2 was highly expressed in the antennae of both male and female P. yasumatsui adults, while its expression was negligible in other tissues. PyasOBP2 was prokaryotically expressed, and purified by Ni-NTA resin. The fluorescence competitive binding assays with 38 plant volatiles from Z. jujuba showed that PyasOBP2 could bind with a broad range of plant volatiles, and had strongest binding capacities to host-plant volatiles like ethyl butyrate (Ki = 3.02 μM), 2-methyl-1-phenylpropene (Ki = 4.61 μM) and dipentene (Ki = 5.99 μM). The three dimensional structure of PyasOBP2 was predicted by homology modeling, and the crystal structure of AgamOBP1 (PDB ID: 2erb) was used as a template. The molecular docking results indicated that the amino acid residue Phe114 of PyasOBP2 could form hydrogen bonds or hydrophobic interactions with some specific ligands, so this residue might play a key role in perception of host plant volatiles. Our results provide a basis for further investigation of potential functions of PyasOBP2, and development of efficient monitoring and integrated pest management strategies of P. yasumatsui. [ABSTRACT FROM AUTHOR]

The reactivity of N‐tosyl vinylaziridines toward arynes has been demonstrated under mild and transition‐metal‐free conditions to yield 2‐(phenanthren‐9‐yl)ethan‐1‐sulfamides in moderate to good yields. The selective synthesis of N‐H and N‐aryl products was accomplished using CsF in MeCN and KF/18‐C‐6 in 1,4‐dioxane, respectively. This cascade process involves a sequential Diels‐Alder reaction, ring‐opening aromatization, ene‐reaction, and selective N‐arylation reaction. [ABSTRACT FROM AUTHOR]

Developing non‐precious bifunctional electrocatalysts to drive the over water splitting that can operate well at high current densities (1,000 mA/cm2) is an urgent requirement for viable electrolysis of water. Transition metal oxides (TMO) have been intensely investigated as one of the most efficient oxygen evolution reaction (OER) catalysts. Unfortunately, their sluggish reaction kinetics towards hydrogen evolution reaction (HER) bring about poor overall performance. In this study, we perform a simple method to obtain the bifunctional TMO‐based electrocatalyst by in‐situ tailoring the components of cobalt nickel molybdenum oxide on nickel foam. By optimizing the annealing temperature and reaction atmosphere, we integrate HER‐active (CoMoNi) and OER‐active (CoMoOx) components together as bifunctional electrocatalysts for overall water splitting. Impressively, the as‐synthesized electrocatalyst shows the high electrocatalytic activity for both OER and HER, and exhibit a low cell voltage of 1.59 V at 10 mA cm−2 when applied as both the cathode and anode in alkaline solutions. Impressively, the bifunctional electrocatalysts work well at large current densities, even in the order of 1,000 mA cm−2 (only need the cell voltage of ∼2.03 V), and remain its activity more than 20 h. Such an outstanding performance should be mainly attributed to integrated high electronic conductivity, 3D self‐supported structure, and good compatibility between HER‐active and OER‐active components. This study shows a positive model for the design of more promising and practical catalysts for full water splitting. On the fly: in‐situ formed hydrogen evolution reaction‐active (CoMoNi) and oxygen evolution reaction‐active (CoMoOx) components are integrated on nickel foam as bifunctional electrocatalyst for overall water splitting. It requires a low cell voltage of ∼2.03 V to reach a current density of 1,000 mA cm−2, and remains activity for more than 20 h. [ABSTRACT FROM AUTHOR]

To meet the progressive requirements for bone regeneration purpose, injectable hydrogels have attracted increasing attention in tissue regeneration and local drug delivery applications. In this study, we report a facile method to prepare injectable and degradable polysaccharide-based hydrogels doubly integrated with hydroxyapatite (HAp) nanoparticles and calcium carbonate microspheres (CMs) under physiological condition. The mechanism of cross-linking is attributed to the Schiff-base reaction between amino and aldehyde groups of carboxymethyl chitosan (CMCS) and oxidized alginate (OAlg), respectively. Synchronously, tetracycline hydrochloride (TH) loaded CMs were fabricated by the precipitation reaction with an average diameter of 6.62 μm. To enhance bioactive and mechanical properties, nano-HAp and CMs containing TH were encapsulated into the polysaccharide-based hydrogel to form injectable gel scaffolds for imitation of bone niche. The gelation time, morphology, mechanical properties, swelling ratio and in vitro degradation of the gel scaffolds could be controlled by varying HAp and CMs contents. Moreover, the composite gel scaffolds had good sustained drug release and antibacterial properties, as confirmed by drugs release calculation and antibacterial evaluation. In addition, the gel scaffolds were found to be self-healing due to dynamic equilibrium of the Schiff-base linkages. These results suggested that the prepared composite gel scaffolds hold great potential for drug delivery and regeneration of irregular bone defects. [ABSTRACT FROM AUTHOR]

For practical adipose regeneration, the challenge is to dynamically deliver the key adipogenic insulin-like growth factors in hydrogels to induce adipogenesis. In order to achieve dynamic release, smart hydrogels to sense the change in the blood glucose concentration is required when glucose concentration increases. In this study, a heparin-based hydrogel has been developed for use in dynamic delivery of heparin nanospheres containing insulin-like growth factor. The gel scaffold was facilely prepared in physiological conditions by the formation of boronate-maltose ester cross-links between boronate and maltose groups of heparin derivatives. Due to its intrinsic glucose-sensitivity, the exposure of gel scaffold to glucose induces maltose functionalized nanospheres dissociation off hydrogel network and thereby could dynamically move into the microenvironment. The potential of the hydrogel as a cell scaffold was demonstrated by encapsulation of human adipose-derived stem cells (ASCs) within the gel matrix in vitro. Cell culture showed that this dynamic hydrogel could support survival and proliferation of ASCs. This biocompatible coupling chemistry has the advantage that it introduces no potentially cytotoxic groups into injectable gel scaffolds formed and can create a more biomimetic microenvironment for drug and cell delivery, rendering them more suitable for potential in vivo biomedical applications. All these results indicate that this biocompatible gel scaffold can render the formulation of a therapeutically effective platform for diabetes treatment and adipose regeneration. [ABSTRACT FROM AUTHOR]

Graphene-based electrocatalysts have been extensively developed as a metal-free alternative to noble metals for the oxygen evolution reaction (OER). Till date, however, their OER performance is far from satisfactory in terms of both activity and stability due to low amount of active sites and a severe aggregation/restacking effect. Herein, we developed the in situ growth of nitrogen-doped, oxygen-functionalized and edge/defect-rich vertically aligned graphene nanosheets on the surface of a carbon cloth (N, O-VAGNs/CC). The separate graphene nanosheets fixed to the surface of the carbon cloth could effectively avoid aggregation. In addition, the vertically aligned morphology provides a highly superficial area and open space, resulting in maximally exposed active sites and unhindered gas transport. Moreover, compared with undoped graphene, the N, O-VAGNs/CC possesses numerous functional groups, abundant defects and active-edges, which are favorable to OER activity. Impressively, this graphene design drastically enhanced OER activity with an overpotential of 351 mV and a Tafel slope of 38 mV dec−1 in alkaline solution, which is superior even to the state-of-the-art RuO2 electrocatalysts, indicating remarkable stability and durability in alkaline media. This study may provide an insight into the design and fabrication of alternatives to noble metal-based catalysts for the OER. [ABSTRACT FROM AUTHOR]

The design and development of non-noble metal electrocatalysts for the hydrogen evolution reaction (HER) is highly desirable, but still cannot satisfy actual requirements in terms of superior activity, ultrahigh stability and ability to carry large current densities. In this study, Ni nanoparticles anchored onto MoO2 nanowires have been synthesized on carbon cloth via in situ exsolution under a reducing atmosphere. Impressively, the obtained Ni–MoO2-450 NWs/CC exhibits an excellent platinum-like HER activity with a nearly zero onset overpotential and a small Tafel slope of ∼30 mV dec−1, which implies that the fast recombination step is rate-limiting. Surprisingly, our sample gives an unprecedented stable catalytic activity over 320 hours in 1 M KOH, and can retain its activity at large current densities, even in the order of 1000 mA cm−2, which is far better than other reported catalysts. Such an outstanding performance should be mainly attributed to the integrated 3D self-supported nanocatalyst, the high electronic conductivity framework and the synergistic coupling effect between Ni and MoO2 interfaces. This work may thus provide an insight into the design and fabrication of alternative catalysts to Pt-based catalysts for the HER. [ABSTRACT FROM AUTHOR]