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Background Although the treatments of skin wounds have greatly improved with the increase in therapeutic methods and agents, available interventions still cannot meet the current clinical needs. Therefore, the development of new pro-regenerative therapies remains urgent. Owing to their unique characteristics, both nanomaterials and peptides have provided novel clues for the development of pro-regenerative agents, however, more efforts were still be awaited and anticipated. Results In the current research, Hollow polydopamine (HPDA) nanoparticles were synthesized and HPDA nanoparticles loading with RL-QN15 (HPDAlR) that was an amphibian-derived peptide with obvious prohealing activities were prepared successfully. The characterization, biodistribution and clearance of both HPDA nanoparticles and HPDAlR were evaluated, the loading efficiency of HPDA against RL-QN15 and the slow-releasing rate of RL-QN15 from HPDAlR were also determined. Our results showed that both HPDA nanoparticles and HPDAlR exerted no obvious toxicity against keratinocyte, macrophage and mice, and HPDA nanoparticles showed no prohealing potency in vivo and in vitro. Interestingly, HPDAlR significantly enhanced the ability of RL-QN15 to accelerate the healing of scratch of keratinocytes and selectively modulate the release of healing-involved cytokines from macrophages. More importantly, in comparison with RL-QN15, by evaluating on animal models of full-thickness injured skin wounds in mice and oral ulcers in rats, HPDAlR showed significant increasing in the pro-regenerative potency of 50 and 10 times, respectively. Moreover, HPDAlR also enhanced the prohealing efficiency of peptide RL-QN15 against skin scald in mice and full-thickness injured wounds in swine. Conclusions HPDA obviously enhanced the pro-regenerative potency of RL-QN15 in vitro and in vivo, hence HPDAlR exhibited great potential in the development of therapeutics for skin wound healing. Graphic Abstract

openaire: EC/H2020/796280/EU//CADOACCFAP The unique antibacterial characteristics of Ag nanomaterials offer a wide potential range of applications, but achieving rapid and durable antibacterial efficacy is challenging. This is because the speed and durability of the antibacterial function make conflicting demands on the structural design: the former requires the direct exposure of Ag to the surrounding environment, whereas the durability requires Ag to be protected from the environment. To overcome this incompatibility, we synthesize sandwich-structured polydopamine shells decorated both internally and externally with Ag nanoparticles, which exhibit prompt and lasting bioactivity in applications. These shells are biocompatible and can be used in vivo to counter bacterial infection caused by methicillin-resistant Staphylococcus aureus superbugs and to inhibit biofilm formation. This work represents a new paradigm for the design of composite materials with enhanced antibacterial properties.

Olivine-type LiFexMn1-xPO4/C cathode materials are of great interest for lithium-ion batteries because of their higher lithium ion intercalation potential compared with that of LiFePO4. Two types of LiFe0.5Mn0.5PO4/C nanorods with different sizes and crystal structures were synthesized through a facile glycol-based solvothermal process with different precursor feeding sequences. The microstructural investigation revealed that the size and structure of the LiFe0.5Mn0.5PO4 nanorods can be tuned by nucleation and crystal growth rates of the intermediate precipitates, which can be controlled by precursor feeding sequence. The LiFe0.5Mn0.5PO4 nanorods obtained through the first feeding sequence (a solution of transition metal salts was added dropwise into the solution mixture of LiOH and H3PO4) exhibited less exposure of the (010) crystal faces and had bigger sizes compared with those of the LiFe0.5Mn0.5PO4 nanorods obtained through the second feeding sequence (a LiOH solution was added dropwise into the solution mixture of H3PO4 and transition metal salts). Electrochemical investigations indicated that the LiFe0.5Mn0.5PO4 nanorods obtained through the second feeding sequence showed substantially improved electrochemical performance, in which the discharge capacities reached 157 and 119 mAh g−1 at 0.2 and 5 C, respectively. Furthermore, a capacity retention of 89% was obtained after 500 cycles at 1 C, demonstrating excellent cyclic stability.

The clean-up of oil spills is a worldwide challenge for the prevention of serious environmental pollution. Therefore, it is imperative to develop materials for oil-spill cleanup that have high absorption/separation capacity, good selectivity, controlled collection and easy recyclability. Here, we present a facile and low-cost approach for fabricating magnetic, durable, and superhydrophobic carbon sponges. The resultant carbon sponges feature fast magnetic response, excellent superhydrophobicity/superoleophilicity, high chemical resistance, environmental stability and mechanical durability, as well as high oil/water separation efficiency and oil absorbency. More importantly, given the magnetically controllable property endowed by magnetic particles to superhydrophobic carbon sponges, which act as magnetically controlled “smart absorbents”, the carbon sponges can therefore controllably and selectively adsorb oils from oil-water mixtures. Thus, our strategy may open up a new avenue for developing magnetic responsive intelligent oil sorbent materials suitable for practical applications in the fields of water remediation, oil spill clean-up and oil recovery.

High–energy density lithium-sulfur (Li-S) batteries suffer from short cycling lifespan, poor rate capability, and low sulfur utilization. Here we report design and synthesis of hierarchical porous g-C3N4/reduced graphene oxide (r-GO) as light-weight sulfur host material for Li-S batteries via a poly-condensation method using silica nanoparticles as hard templates. Microstructure of the g-C3N4/r-GO architecture has been characterized. Electrochemical evaluations indicate that the g-C3N4/r-GO/S composite cathode with 75 wt% of sulfur and moderate macropore density in the host material displays the best Li-storage properties. The reversible capacity reaches 589.6 mAh g−1 after 100 cycles at a current rate of 2 C (3.35 A g−1). Especially the rate capability is excellent. Even at 3.5 C, the reversible capacity can reach 55% of the capacity at 0.2 C. This light-weight g-C3N4/r-GO architecture composed of electrical conductive r-GO layers, polar g-C3N4, and hierarchical pores is a promising sulfur host material for high-performance Li-S batteries.

Surface-enhanced Raman scattering (SERS) allows for label-free detection of analyte molecules with high sensitivity, but it is still vastly challenged for the detection of ultra-highly diluted analyte solutions in practice, e.g., femtomolar concentrates, 10−15 M. Here, we report a facile approach for the fabrication of hierarchical superhydrophobic melamine-formaldehyde/Ag (MF/Ag) nanocomposite array substrates, applicable for ultra-highly sensitive SERS detection of biological analytes at very low concentrations up to femtomolar levels. Hierarchical superhydrophobic MF/Ag nanocomposite arrays are synthesized by integrating colloidal lithography at the air-liquid interface and in-situ interfacial reactions. These substrates can confine analyte molecules within the localized sensing regions, so as to effectively prevent the random spread of analyte molecules. In this way, these substrates are able to detect dopamine with a detection limit of 10-15 M, and with a SERS enhancement factor (EF) as high as 3.21 × 1010. The substrates are durable and the SERS results are reproducible. For practical demonstration, these superhydrophobic SERS-active substrates are also applied for detecting proteins, lysozyme and hemoglobin at low concentrates. This work presents a straightforward way to synthesize the hierarchical superhydrophobic SERS-active substrates with superior sensitivity and long-term reproducibility, with rational modification, which might merit the practical SERS applications in detection of drug and pollutants in extremely dilute environments.

To improve electrochemical performance of MnO-based anode materials for high energy-density lithium-ion batteries, porous MnO/g-C3N4/carbon composite spheres have been synthesized through an aerosol-pyrolysis route. Microstructural investigations indicate that ultrafine MnO particles are homogeneously embedded in the three-dimensional g-C3N4/carbon porous spheres. The electrochemical properties of the porous MnO/g-C3N4/carbon composite spheres have been systematically evaluated. The porous MnO/g-C3N4/carbon composite spheres with g-C3N4/carbon content of 8.6 wt.% display excellent electrochemical properties, in which the first-cycle discharge capacity reaches 1096.8 mAh g−1 at 0.2 C, and the discharge/charge capacities reach 918.9/605.8 mAh g−1 at 0.5 C. The highest reversible capacity is 781.9 mAh g−1, which is higher than the theoretical capacity of MnO (755 mAh g−1). Furthermore, the reversible capacity retention reaches 99% after 150 cycles at 0.5 C. The three-dimensional porous g-C3N4/carbon conductive network, the ultrafine MnO particles with homogeneous distribution and the pseudocapacitive behavior are the main reasons for enhancement of the electrochemical performance of the MnO/g-C3N4/carbon composite spheres.

It is of great significance to timely, accurately, and effectively monitor land use/cover in city regions for the reasonable development and utilization of urban land resources. The remotely sensed dynamic monitoring of Land use/land cover (LULC) in rapidly developing city regions has increasingly depended on remote-sensing data at high temporal and spatial resolutions. However, due to the influence of revisiting periods and weather, it is difficult to acquire enough time-series images with high quality at both high temporal and spatial resolution from the same sensor. In this paper we used the temporal-spatial fusion model ESTARFM (Enhanced Spatial and Temporal Adaptive Reflectance Fusion Model) to blend Landsat8 and MODIS data and obtain time-series Landsat8 images. Then, land cover information is extracted using an object-based classification method. In this study, the proposed method is validated by a case study of the Changsha City. The results show that the overall accuracy and Kappa coefficient were 94.38% and 0.88, respectively, and the user/producer accuracies of vegetation types were all over 85%. Our approach provides an accurate and efficient technical method for the effective extraction of land use/cover information in the highly heterogeneous regions.

Background Baricitinib, an oral-administrated selective inhibitor of the JAK1 and JAK2, is recently approved for rheumatoid arthritis (RA) treatment. With the aim to provide some insights on the clinical safety, the current study mainly focused on the effect of baricitinib on low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) levels and cardiovascular risk. Methods The net change scores [least squares mean (LSM) and mean change] of LDL-C and HDL-C levels from baseline with the comparison of baricitinib versus placebo were pooled, respectively. Risk rations (RR) of major cardiovascular events (MACEs) and differences of cardiovascular risk scores at the end of treatment across groups were compared. Results Six trials with randomized 3552 patients were finally included in summary analysis. Results showed that baricitinib significantly increased LDL-C levels, the net mean change was 13.15 mg/dl with 95% CI 8.89~17.42 (I2 = 0) and the net LSM was 11.94 mg/dl with 95% CI 7.52~16.37 (I2 = 84%). HDL-C also increased obviously with the net LSM change was 7.19 mg/dl (95% CI, 6.05~8.33, I2 = 47%) and net mean change was 5.40 mg/dl (95% CI, 3.07~7.74, I2 = 10%). Subgroup and meta-regression analysis demonstrated baricitinib induced LDL-C and HDL-C increases in a dose-response manner. However, both the pooled RRs of MACEs and differences of cardiovascular risk scores were not statistically significant across groups. Conclusion This study confirmed that baricitinib induced a stable dose-response increase in LDL-C and HDL-C levels. Since the causality association between altered lipids and cardiovascular risk was not identified yet, this issue cannot be completely dismissed. Future research is needed to fully dissect the implications of these lipid changes. Electronic supplementary material The online version of this article (10.1186/s12944-019-0994-7) contains supplementary material, which is available to authorized users.

Low mechanical strength, poor processability, and low bioactivity of hydrogels limit their application in bone tissue engineering severely. Herein, a new 3D-printable, osteoinductive, and bioenergetic-active double-network (DN) hydrogel containing sodium alginate (SA), poly (ethylene glycol) diacrylate (PEGDA), and sodium polyphosphate (PolyP) was developed via a two-step method. The synergy of the covalent cross-linking network and the ionic cross-linking network improves the mechanical properties of the hydrogel. And the pre-gel with Ca2+ has better 3D printing performance to print complex tissue engineering scaffolds than common hydrogels. In addition, the incorporation of PolyP into DN hydrogel matrix significantly improves the bioactivity of hydrogels. The bioenergetic effect of PolyP improves adenosine triphosphate content of cells significantly to promote cell activities such as migration. The in vitro osseointegration investigation suggests that the orthophosphate monomer units, which are degradation fragments of PolyP, provide enough phosphoric acid units for the formation of calcium phosphate and accelerate the osteogenic differentiation of cells greatly. Therefore, the proposed printable, bioenergetic-active, osteoinductive DN hydrogel is potential to solve the problems of complex tissue engineering scaffolds and be applied in energy-crucial bone tissue regeneration.

A new strategy of simplification therapy shown the unique benefits in clinical treatment, by reducing pill burden and avoid drug exposure. To provide more evidence for the strategy, we compared the efficacy and safety of dolutegravir (DTG)-containing simplified dual combination antiretroviral therapy (cART) and traditional triple cART for people living with HIV/AIDS. The meta-analysis of randomized controlled trials compared DTG-containing dual therapy with triple cART. The primary outcome was virologic suppression. The secondary outcomes included CD4T cell recovery, lipids change from baseline, and adverse events (AEs). A total of 7 studies, 4852 patients were eligible, 2423 (49.9%) received DTG-based simplified dual cART, and 2429 (50.1%) received triple cART. The viral suppression rate was 94.7% at 24 weeks, 93.0% at 48 weeks, and 96.6% at 96 weeks in dual cART. The viral suppression rate of dual cART was non-inferior to triple cART at 24 weeks (risk difference [RD], -0.00; 95% confidence interval [CI] -0.02-0.01), at 48 weeks (RD, -0.01; 95% CI -0.02-0.01), and at 96 weeks (RD, -0.01; 95% CI -0.02-0.00). Sub-analysis results were consistent with the overall results. With regard to other outcomes (CD4T counts, lipids, any AEs, and AEs grade ≥ 3), there was no significant statistical difference between the two regimens. DTG-based simplified dual cART was non-inferior to triple cART in terms of efficacy and safety. This finding provides strong support for current consensus guidelines recommended the dual regimen as first-line treatment.

Various pollutants in wastewater including water-insoluble oils and water-soluble toxic organic pollutants, have been threatening ecosystems and human health, making wastewater purification difficult. Inspired by the hierarchical structures and chemical compositions of lotus leaf, we combined the usage of polydopamine (PDA) chemistry and photocatalytically active TiO2 to develop a facile approach toward composite PDA-based TiO2 coated mesh with restorable superhydrophobicity. In this procedure, PDA assisted loading of TiO2 nanoparticles onto stainless steel mesh with a result of micro/nanoscale hierarchical surface was achieved via a single-step solvothermal method. After modified with 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane, this mesh became superhydrophobic. The TiO2 coated mesh exhibited enhanced superhydrophobicity, excellent environmental stability, robust chemical resistance and high mechanical durability. Moreover, it has been demonstrated the high separation capacity and extraordinary recyclability for various oils collection from water due to its special surface superhydrophobicity. Importantly, such a mesh possessed photocatalytic activity due to the embedded TiO2, which allowed for the effective degradation of organic pollutants under UV irradiation, representing a plausible way to restore superhydrophobic surface by photocatalytically decomposing the attached contaminants. This investigation suggests a green and facile way to prepare superhydrophobic materials with restored surface wetting property, which will be useful for wastewater purification. Graphical abstract: [Figure not available: see fulltext.]

Standard plane recognition plays an important role in prenatal ultrasound (US) screening. Automatically recognizing the standard plane along with the corresponding anatomical structures in US image can not only facilitate US image interpretation but also improve diagnostic efficiency. In this study, we build a novel multi-label learning (MLL) scheme to identify multiple standard planes and corresponding anatomical structures of fetus simultaneously. Our contribution is three-fold. First, we represent the class correlation by word embeddings to capture the fine-grained semantic and latent statistical concurrency. Second, we equip the MLL with a graph convolutional network to explore the inner and outer relationship among categories. Third, we propose a novel cluster relabel-based contrastive learning algorithm to encourage the divergence among ambiguous classes. Extensive validation was performed on our large in-house dataset. Our approach reports the highest accuracy as 90.25\(\%\) for standard planes labeling, 85.59\(\%\) for planes and structures labeling and mAP as 94.63\(\%\). The proposed MLL scheme provides a novel perspective for standard plane recognition and can be easily extended to other medical image classification tasks.

The introduction of the self-healing function into superhydrophobic surfaces has recently raised increasing attention because it can renew the feature of the surface iteratively to a large extent to extend the service life span of the surface in practical applications. However, it still faces a great challenge on how to achieve this unique surface with a tunable self-healing function via an easy and effective way. Here, we propose a general, yet easily implemented strategy to endow a diversity of commercial substrates with self-healable superhydrophobic surfaces mainly relying on the collective use of the polydopamine (PDA) chemistry with a hydrophobic silane-octadecyltrimethoxysilane (ODTMS). Upon applying ultrasonication for 30 min to an alkaline aqueous solution comprising dopamine hydrochloride (DA) and ODTMS, ODTMS disperses into the aqueous phase as microdroplets, while DA polymerizes into PDA exclusively onto the micro-sized oil droplets, forming capsules with nanoroughness. In the presence of substrates, PDA also anchors these composite capsules onto substrates, resulting in hierarchical surfaces. ODTMS is detected abundantly on the hierarchical surfaces, leading to superhydrophobic surfaces. Remarkably, this superhydrophobicity is self-restorable at room temperature (e.g., days) once it is deteriorated by the air plasma or extremely acid/alkali treatment, and this self-restoration can be significantly accelerated via the heating (2 h) or rubbing (5 min) treatment. Generally, heating and rubbing are the valid ways to induce self-healing, which is speculated to accelerate the migration of hidden ODTMS from the capsules to the surfaces because of the minimization of the global surface-free energy. Benefiting from the self-healing superhydrophobicity, we devise oil/water separation using various surface-modified commercial fabrics, which exhibit a prolonged life span in applications and may further facilitate other usage in environmental remediation and water purification.

BackgroundCases with coronavirus disease 2019 (COVID-19) emigrated from Wuhan escalated the risk of spreading in other cities. This report focused on the outside-Wuhan patients to assess the transmission and clinical characteristics of this illness.MethodsContact investigation was conducted on each patient who admitted to the assigned hospitals in Hunan Province (geographically adjacent to Wuhan) from Jan 22, 2020 to Feb 12, 2020. Demographic, clinical, laboratory and radiological characteristics, medication therapy and outcomes were collected and analyzed. Patients were confirmed by PCR test.ResultsOf the 104 patients, 48 (46.15%) were imported cases and 56 (53.85%) were indigenous cases; 93 (89.42%) had a definite contact history with infections. Family clusters were the major body of patients. Transmission along the chain of 3 “generations” was observed. Mean age was 43 (rang, 8-84) years (including 3 children) and 49 (47.12%) were male. Most patients had typical symptoms, 5 asymptomatic infections were found and 2 of them infected their relatives. The median incubation period was 6 (rang, 1-32) days, of 8 patients ranged from 18 to 32 days. Just 9 of 16 severe patients required ICU care. Until Feb 12, 2020, 40 (38.46%) discharged and 1 (0.96%) died. For the antiviral treatment, 80 (76.92%) patients received traditional Chinese medicine therapy.ConclusionsFamily but not community transmission occupied the main body of infections in the two centers. Asymptomatic transmission demonstrated here warned us that it may bring more risk to the spread of COVID-19. The incubation period of 8 patients exceeded 14 days.

Developing robust and inexpensive non-noble metal based anode electrocatalysts is highly desirable for alkaline direct methanol fuel cells (ADMFCs). Herein, we successfully develop a facile self-template synthetic strategy for gram-grade porous NiO nanotubes (NTs) by pyrolyzing a nanorod-like Ni-dimethylglyoxime complex. The pyrolysis temperature highly correlates with the morphology and crystallinity of NiO NTs. The optimal NiO NTs exhibit a large electrochemically active surface area, a fast catalytic kinetics, and a small charge transfer resistance, which induce an outstanding electrocatalytic activity for the methanol oxidation reaction (MOR). Compared with conventional NiO nanoparticles, NiO NTs achieve a 11.5-fold increase in mass activity at 1.5 V for the MOR due to nanotubal morphology and abundant non-vacancy defects on the NiO NT surface. Moreover, NiO NTs have a higher electrocatalytic activity for the intermediates of the MOR (such as formaldehyde and formate) than conventional NiO nanoparticles, which also contribute to MOR activity enhancement. Given the facile synthesis and enhanced electrocatalytic performance, NiO NTs may be promising anode electrocatalysts for ADMFCs.

Inspired by mussel-adhesion phenomena in nature, we present a simple, mild and green method to prepare polystyrene/Ag (PS/Ag) nanocomposite particles with enhanced antibacterial activities. In this approach, monodisperse polystyrene particles are used as template spheres, which are then coated with polydopamine (PDA) through the self-polymerization of dopamine in a weakly alkaline aqueous environment (pH = 8.5). Silver precursor-[Ag(NH3)2]+ ions are added and absorbed onto the surfaces of the PS/PDA composite spheres by the active catechol and amine groups of the polydopamine coating. Meanwhile, these adsorbed [Ag(NH3)2]+ ions are in situ reduced into metallic silver nanoparticles by the “bridge” of the polydopamine coating, and the formed Ag nanoparticles are home positioned. As polydopamine is an environmentally friendly reagent with abilities as a universal adhesive to any surface and as a mild reductant for noble metal salts, because of its abundant active catechol and amine groups, neither additional reducing and toxic reagents nor special surface modifications of the template are needed in this procedure. Moreover, preliminary antibacterial assays indicate that these PS/Ag nanocomposite particles show enhanced antibacterial activities against Escherichia coli (Gram-negative bacteria) and Staphylococcus aureus (Gram-positive bacteria), while they do not show significant in vitro cytotoxicity against HEK293T human embryonic kidney cells. These results suggest that these PS/Ag nanocomposite particles could be promising antibacterial materials for future biomedical applications.

In order to realize the double-mode absorption, double-defect photonic crystal is formed. For the upper defect, the graphene multilayer is placed on the top of photonic crystal acting as the surface defect, while for the one below, the pure dielectric destroying the periodicity of photonic crystal services as the internal defect. Depending on FP resonance, two modes achieve perfect absorption at critical coupling. Merely, the mode-dependences are different, so that these modes have different distinctly Q factors and can be tuned independently by changing the chemical potential of graphene and the size of defect. Combining the angle response, the independence-tuning of modes becomes more flexible. Besides, both of modes’ frequencies and amplitudes are enslaved to the layer number of graphene. And the period of photonic crystal affects directly the peak–peak distance and modes number.

Surface-enhanced Raman scattering (SERS) has been demonstrated to be an ultrasensitive and real-time analysis technique for detection of analytes with its specific fingerprint-identification feature. However, most traditional SERS-active substrates are suffering from their high expense, intricate fabrication processes and non-recyclability, which seriously hinder the applicable universality of SERS analytical technique. Thus, it is highly desired to develop highly sensitive SERS-active substrates that can be recovered in an easy way. Herein, we present a facile and inexpensive approach for fabrication of photocatalytically active Ag-coated CuO (denoted as CuO@Ag) microbowl array substrate, applicable for the highly efficient, ultrasensitive, and recyclable SERS detection. In this approach, a multifunctional CuO@Ag microbowl array is achieved based on the pre-synthesis of a quasi-2D CuO microbowl array by employing the colloidal lithography on Cu foil combined with the subsequent chemical oxidation reaction, and followed by the sputtering deposition of Ag layer on the CuO microbowl array. Importantly, this CuO@Ag microbowl array can serve as SERS-active substrate with extra advantageous feature of excellent photocatalytic activity, which enables self-degradation of analytes after the SERS-detection under visible light illumination. Remarkably, this allows for recyclable SERS detection. In the detection of model probe molecules, e.g., methylene blue (LOD: 1.3×10-16 M) and Aflatoxin B1 (LOD: 6.5×10-15 M), approximate femtomolar level can be reached. Impressively, this substrate allows multi-detection without compromising the SERS activity. The present research provides a new and cost-effective strategy for synthesizing recyclable SERS-active substrates, which suggests plausible ways in the design of multi-functional SERS-active substrates.

A facile and environmentally friendly approach was proposed to decorate Ag nanoparticles on melamine-formaldehyde (MF) colloidal particles (MF/Ag composite microspheres). In this approach, monodisperse MF colloidal particles were prepared via a two-step organic sol-gel process and served as the active templates for the decoration of Ag nanoparticles. Then, the [Ag(NH3)2]+ ions as the Ag precursors can be adsorbed onto the surfaces of the MF colloidal particles and were in situ reduced into metallic Ag nanoparticles, forming MF/Ag composite microspheres. During this synthesis, neither presurface activation nor extra reductants were necessary. These MF/Ag composite microspheres can be used as the surface-enhanced Raman scattering (SERS) active substrates for the trace detection of organic compounds, e.g., 4-aminobenzenethiol (4-ABT) and penicillin G sodium. Furthermore, these MF/Ag composite microspheres also showed excellent antibacterial activities against both Escherichia coli (E. coli, gram-negative bacteria) and Staphylococcus aureus (S. aureus, gram-positive bacteria).

Spinel-type Li4Ti5O12 has peculiar advantages in ultralong cyclic lifespan and high safety. However, its intrinsic low electrical conductivity strongly restricts its applications. Self-assembled mesoporous Li4Ti5O12/C hollow spheres have been obtained through an aerosol pathway, in which the mesoporous shells consist of Li4Ti5O12 nanoparticles embedded in amorphous carbon. Electrochemical performance of the mesoporous Li4Ti5O12/C hollow spheres has been evaluated, which demonstrate their excellent cyclic capacity, stability and rate capability for high power-density and long lifespan lithium-ion batteries. The initial reversible capacity reaches 164.3 mAh g−1 at 0.5 C, which is 93.9% or 98.3% of the theoretical capacity with or without carbon content. The capacity fading rate of each cycle is as low as 0.012%. A self-assembly mechanism of the mesoporous Li4Ti5O12/C hollow spheres has been proposed, which is expected to be beneficial for self-assembling hollow spherical structures with applications in batteries.

Hierarchical one-dimensional (1D) hollow nanostructures have attracted intense research attention due to their unique structures that may be capable of many promising applications. Here, we report a facile and effective strategy to prepare nickel silicate nanotubes (NiSNTs). Using this approach, mesoporous SiO2 nanorods served as sacrificial templates for a simple hydrothermal process to prepare NiSNTs via a self-template route. The obtained NiSNTs preserve the tubular hierarchical morphology and hollow interior structures, which confer the NiSNTs with high surface areas and large pore volumes. These features point to NiSNTs as superior candidates for efficiently adsorbing heavy metal ions and organic dyes in wastewater. Moreover, NiSNTs can also serve as both supports and nickel sources, forming nickel silicate/nickel nanocomposite tubes (NiSNTs/Ni) via in situ reduction of NiSNTs under hydrothermal conditions. The addition of nickel precursors and surface pre-activation are therefore unnecessary. The NiSNTs/Ni exhibit efficient and recyclable catalytic properties when used for the reduction of 4-nitrophenol (4-NP). With a rational adaption, we believe this synthetic strategy can be extended to fabricate multifunctional one-dimensional hollow nanostructures with diverse compositions and morphologies, which may be useful for environmental protection, catalysis, energy and many other important domains.

Engineering hollow particles with high complexity in their morphology or composition is highly desirable for both fundamental studies and practical applications. Here, we combine mussel-inspired polydopamine (PDA) chemistry with template-assisted and hydrothermal approaches to explore a general approach for engineering hollow PDA colloidal composite particles with tunable complexities in terms of particle geometry, shell architecture and chemical composition. PDA coating and hydrothermal treatment are carried out sequentially in the same environment, which not only simplifies the experimental procedure but also avoids the use of hazardous core-removers. This approach is generally applicable to a wide variety of colloidal templates irrespective of their shape, material and structure, allowing the void structure and geometry (spherical void, yolk-shell, multi-shells and non-spherical cavity) to be controlled. The surface of the PDA shell provides a versatile platform for a number of secondary reactions (e.g., electroless metallization, superhydrophobic modification, Michael addition and nanoparticle decoration). Consequently, tuning the exterior or interior of the hollow PDA shell with various functional materials offers a range of potential uses in superhydrophobic surfaces, catalysis, photocatalysis and surface-enhanced Raman spectrum sensing.

Surface-enhanced Raman scattering (SERS) sensor allows for fingerprinting and label-free molecular detection with a high sensitivity, but the simple fabrication of SERS active substrates with a well-control over the SERS performance, e.g. an ultra-high sensitivity, superior reproducibility and long-term stability remain a great challenge. Here, we introduce an easy strategy for synthesizing polydopamine-Ag microbowl/nanoparticle array (PDA-Ag MNA) substrates with a tunable superhydrophobic surface, applicable for ultra-highly sensitive SERS detection. First, the periodically dented PDA films are prepared by polymerizing dopamine onto 2D polystyrene colloidal crystals formed at the liquid/air interface, and followed with an in-situ reduction of Ag ions to Ag nanoparticles after removing polystyrene. The surface morphology, i.e. microbowl/nanoparticle structure, is well-controlled, therefore, allowing that the SERS activity of the substrate is under control. Inspired by the superhydrophobic hierarchical surface of the rose petals, this analogous MNA surface is subsequently endowed to be superhydrophobic. This way, the SERS detection of ultra-dilute solute (10−14 M) can be achieved by concentrating analytes within a localized region. Moreover, this substrate also shows a superior reproducibility in result and durability in use. This strategy exhibits a realistic paradigm for further improving the sensitivity of the SERS technique.

The mutual compensation of offshore wind energy and wave energy provides a cost-effective solution to offshore power supply. Herein, a novel wind–wave hybrid power generation system with hydraulic transmission is proposed, which consists of a wave energy harvesting part, a wind energy harvesting part, an energy coupling part, and a control part. This system removes the conventional electric regulation components and significantly reduces the negative interaction between the two energy harvesting parts. First, the working principles of the hybrid system, individual wind power generation system, and individual wave power generation system are introduced, and relevant numerical models are established. Next, simulation models of the three systems are established via AMESim and MATLAB/Simulink. Finally, the output power, generator speed, system pressures, and internal flow rates of the hybrid system are compared with those of two individual power generation systems to evaluate the complementary energy performance. Relative to the individual wave power generation system and individual wind power generation system, the hybrid system exhibits enhanced stability of the output power (by 69.42% and 21.03%, respectively) and enhanced stability of the generator speed (by 63.78% and 39.32%, respectively). Furthermore, the hybrid system exhibits a high energy coupling efficiency between 80.34% and 99.12%.

In the actual industrial process, the distribution of historical training data and online testing data is always different due to the switching of operating modes and changes in climate conditions. At this time, the performance of traditional data-driven fault diagnosis methods based on the assumption that historical training data and online testing data follow the same distribution will degrade. Therefore, how to ensure the reliability of the fault diagnosis method for the distribution distortion is necessary yet challenge. In this paper, a cross-domain fault diagnosis method based on transferred stacked autoencoder is proposed. In detail, a stacked autoencoder is firstly used to extract features of a large amount of source domain data, and the features are classified to establish the source domain model. Then, a small amount of target domain data is introduced to fine-tune the source domain model to achieve domain adaptation. The effectiveness and superiority of the proposed deep transfer method was demonstrated through wind turbine system experiment and pump truck experiment. In addition, this paper also discusses the number of layers of the stacked autoencoder and model transfer strategies in detail to help practitioners understand the proposed method in practice.

Hierarchical Ni(OH)2 nanotubes with ultrathin nanoflakes were successfully synthesized by a self-sacrificial template via a facile solvothermal method. The as-prepared Ni(OH)2 nanotubes exhibit a high specific capacitance of 1319 F g-1 at 3 A g-1, and retain 700 F g-1 (79.3% of the initial capacitance) at 5 A g-1 after 7000 cycles.

Polydopamine is a synthetic analogue of natural melanin (eumelanin) produced from oxidative polymerization of dopamine. Owing to its strong adhesion ability, versatile chemical reactivity, biocompatibility and biodegradation, polydopamine is commonly applied as a versatile linker to synthesize colloidal materials with diverse structures, unique physicochemical properties and tunable functions, which allow for a broad scope of applications including biomedicine, sensing, catalysis, environment and energy. In this personal account, we discuss first about the different synthetic approaches of polydopamine, as well as its polymerization mechanism, and then with a comprehensive overview of recent progress in the synthesis and applications of polydopamine-based colloidal materials. Finally, we summarize this personal account with future perspectives.

We combine the active surface of polydopamine (PDA) with the biomimetic mineralization of CaCO3 to obtain the macroscopically continuous CaCO3 films under mild conditions. In this approach, the organic matrices were adhesive PDA coatings, which were dip-coated on silicon wafers by the self-polymerization of dopamine in an alkaline aqueous solution (pH 8.5). The inorganic layers were CaCO3 films, which were formed in a CaCl2 solution in the presence of poly(acrylic acid) (PAA) via a CO2 diffusion method. During the biomimetic mineralization, amorphous calcium carbonate (ACC) was formed on PDA matrices with the help of PAA, which, subsequently, was transformed into a flat continuous calcite film on the PDA matrices. As the mineralization time increased, a new layer of CaCO3 crystals was formed over the calcite and, as a result, led to continuous CaCO3 films with rough surfaces. The thicknesses of CaCO3 films can be controlled by tuning the mineralization time. Our approach may provide a simple, yet efficient way for the preparation of macroscopically continuous organic–inorganic composite CaCO3 films under mild conditions. Moreover, superhydrophobic surfaces can be successfully achieved via a hydrophobic modification of the rough CaCO3 films, which make them suitable candidates for a variety of superhydrophobic applications, such as self-cleaning surfaces or anticorrosion, antiadhesive coatings.

Unlike vision modalities, body-worn sensors or passive sensing can avoid the failure of action understanding in vision related challenges, e.g. occlusion and appearance variation. However, a standard large-scale dataset does not exist, in which different types of modalities across vision and sensors are integrated. To address the disadvantage of vision-based modalities and push towards multi/cross modal action understanding, this paper introduces a new large-scale dataset recorded from 20 distinct subjects with seven different types of modalities: RGB videos, keypoints, acceleration, gyroscope, orientation, Wi-Fi and pressure signal. The dataset consists of more than 36k video clips for 37 action classes covering a wide range of daily life activities such as desktop-related and check-in-based ones in four different distinct scenarios. On the basis of our dataset, we propose a novel multi modality distillation model with attention mechanism to realize an adaptive knowledge transfer from sensor-based modalities to vision-based modalities. The proposed model significantly improves performance of action recognition compared to models trained with only RGB information. The experimental results confirm the effectiveness of our model on cross-subject, -view, -scene and -session evaluation criteria. We believe that this new large-scale multimodal dataset will contribute the community of multimodal based action understanding.

Recently, instance segmentation models have been developed to a great promising accuracy on public benchmarks. However, these models are too heavy to be applied for real applications due to their low inference speed. In this paper, we propose a faster instance segmentation model utilizing a teacher-student learning framework that transfers the knowledge obtained by a well-trained teacher model to a lightweight student model. In addition to the conventional strategy of knowledge distillation in classification or semantic segmentation networks which are both single-task networks, we investigate a hierarchical distillation (H-Dis) framework for structure information distillation on multi-task learning based instance segmentation. H-Dis consists of two distillation schemes: representation distillation that distills pair-wise quantized feature maps shared by multi-heads, and semantic distillation that makes sure to distill each head information in an instance level. In particular, we present channel-wise distillation for the segmentation head to achieve instance-level mask knowledge transfer. To evaluate our approach, we carry out experiments with different settings of distillation methods on different datasets Pascal VOC and Cityscapes. Our experiments prove that our approach is effective for accelerating instance segmentation models with less accuracy drop under limited computing resources.

In order to increase CSNS beam power from 100 to 500 kW, the linac injection energy needs to be increased from 80 to 300 MeV. The combined layout of superconducting spoke cavities and elliptical cavities will be adopted to accelerate H− beam to 300 MeV. In this paper, a compact single spoke cavity with Φ50-mm beam aperture was proposed, with the RF performance of the spoke cavity optimized to Ep/Eacc value. The simulation got optimum results of Epeak/Eacc = 4.97 and Bpeak/Eacc = 8.42 mT/(MV/m), and the max is 1.52 at Eacc = 7.74 MV/m. A 648 MHz βg = 0.4 single spoke cavity with beam aperture Φ50 mm was proposed in the paper. This compact cavity may be a very promising option for CSNS linac upgrading. In addition to the optimization of the RF parameters, the multipacting behavior of the cavity is also studied, and cavity shape is optimized to reduce value.

Rationale: The treatment of intracranial Acinetobacter baumannii infections is made difficult by multidrug-resistance poor drug penetration through the blood-brain barrier (BBB). Although tigecycline appears to be effective against A baumannii, it is only administered intravenously because it does not readily cross the BBB. The addition of intraventricular (IVT) or intrathecal infusions of tigecycline could revolutionize clinical therapy for intracranial A baumannii infections. However, there are few reports on the successful use of such treatments. Patient concerns: We report the case of a 17-year-old male who presented with high fever and neck rigidity after intracranial drainage. Diagnosis: Intracranial infection with extensively drug-resistant A baumannii after intracranial drainage. Interventions: On the advice of a clinical pharmacist, the patient was administered intrathecal infusions of tigecycline after treatment failure with IVT tigecycline. Outcomes: The patient's body temperature returned to normal. Thereafter, the patient was in good clinical condition without signs of cerebrospinal fluid infection and tuberculosis. Lessons: However, when central nervous system infections fail IVT tigecycline, clinicians should consider changing to intrathecal tigecycline infusions rather than raising the dose of IVT tigecycline. In addition, the co-administration of tigecycline with other drugs that can penetrate the BBB should not be ruled out.

The currently available superhydrophobic coating techniques that utilize mussel-inspired polydopamine coating to construct hierarchical superhydrophobic structures require multiply procedures and are time-consuming processes. Here, we propose an ultrasound-accelerated strategy to various commercial sponges with hierarchically structured superhydrophobic surfaces by briefly submerging sponges into a slightly alkaline aqueous mixture comprising dopamine hydrochloride (DA) and dodecyltrimethoxysilane (DTMS) under ultrasound. The ultrasound is found significantly accelerate the hierarchical surface structures from PDA, while only minorly influences the hydrolysis of DTMS that hydrophobically modifies the surface of PDA. As a result, the hierarchical superhydrophobic surfaces are formed within 25 min. In addition, the superhydrophobicity of the surface can be recovered by repeating this ultrasound-assisted process, provided that the superhydrophobic feature is vanished or lost during their use in a harsh environment. These superhydrophobic sponges are superior materials for oil collection from water, in a durably robust, efficient and recyclable manner with multi-life span. This strategy presents a rather high efficient and time-saving process for constructing/recovering hierarchical superhydrophobic surfaces, which may be useful for the rapid engineering commercial materials with restorable superhydrophobic surfaces.

Microbial contamination caused by bacterial adhesion and colonization onto the materials surfaces has long been a serious threat to human health. Thus, it is imperative to develop advanced antimicrobial materials for bio-applications. Here, a unique polydopamine/ hydroxyapatite/nisin (PDA/HAP/Nisin) composite with good bioactivities and enhanced antibacterial activities have been developed. The uniform PDA particles are first prepared via the dopamine self-polymerization in an alkaline water-ethanol mixed solvent. Due to the abundance surface catecholamine moieties, PDA particles can serve as the powerful templates for the in-situ mineralization of hydroxyapatite (HAP) in a simulated body fluid (SBF) solution, forming PDA/HAP composites. Transmission electron microscopy, scanning electron microscopy, transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction are used to investigate the morphology, surface composition, and crystalline structure of the PDA/HAP composites. These PDA/HAP composites are utilized as the reservoir for loading the antimicrobial peptide–nisin. Ultraviolet visible spectrophotometry analysis shows that PDA/HAP composites have exhibited a high loading capacity and a superior loading efficiency for nisin. The resulting PDA/HAP/Nisin composites are ideal antimicrobial biomaterials for bio-application because they exhibit not only a significant in vitro cytocompatibility to human embryonic kidney HEK293 T cells, but also the enhanced antibacterial activities against Staphylococcus aureus (Gram-positive bacteria). These advantageous properties of the PDA/HAP/Nisin composites allow them as the promising candidates for a broad range of bio-applications, e.g., drug delivery, implant engineering, and bio-scaffold.

In this paper, a coumarin derivative La was designed and synthesized in two steps with simple synthesis method and high yield. Its recognition performance was studied by UV-Vis spectroscopy. It was found that when iron ion (III) was added, the absorption value of the probe molecule La was significantly enhanced, while other metal ions studied did not cause significant changes. Further research on the relationship between absorbance and iron ion (III) concentration revealed that they have a good linear relationship. This shows that the coumarin derivative La has the ability to detect iron ions (III) qualitatively and quantitatively.

A simple and easily synthesized Schiff base chemosensor 1 was prepared by the one-step condensation reaction of 3-acetyl-4-hydroxycoumarin and 1-naphthylamine. The metal ion recognition ability of the chemosensor was measured by UV-Vis spectrophotometer. It demonstrated that its absorbance at 327 nm enhanced upon addition of Fe3+ significantly. The absorption intensities at 327 nm fitted good linear relation (R 2=0.9928) to Fe3+ concentration in DMF. 1 is able to recognize Fe3+ selectively over other ions. The synthesized chemosensor 1 would be useful to detect Fe3+ qualitatively and quantitatively.

Modern industrial systems are increasingly complex with the development of technology and equipment. Due to the variation of process loads and other factors, many processes often switch their operating modes, which results in the problem of multimode process monitoring. In addition, owing to the harsh industrial conditions, monitoring of multimode processes is difficult and challenging. In this paper, a fault classification and isolation method were proposed based on sparse stacked autoencoder network. In detail, a single autoencoder is trained one by one in an unsupervised way. Then, the hidden layer of each trained autoencoder is cascade connected to form a deep structure. Finally, the stacked autoencoder network is followed by a Softmax layer to realize the fault classification task. Since the deep structure can well learn and fit the nonlinear relationship in the process and perform feature extraction more effectively compare with other traditional methods, it can classify the faults accurately. After an in-depth exploration of the deep neural network, a novel fault isolation scheme is proposed. By calculating the contribution rate of each variable, the one with the largest contribution was identified as the fault location. In order to evaluate the efficiency of the proposed method, some numerical experiments were conducted on the continuous stirred tank heater (CSTH) benchmark process as well as two industrial cases including the wind turbines monitoring and the aluminum electrolysis process monitoring in comparison with several traditional methods. The experimental results show that the accuracy of the proposed method in the fault classification process is better than other methods and the fault isolation scheme can well locate the variable that caused the fault.

Synthesis of hollow colloidal particles with a well-defined structure in a single step is challenging and highly desired for numerous applications. We propose a simple and productive approach to synthesize hierarchical nickel hydroxidenitrate hollow colloidal particles (NiHNHCP) with tunable structure and property via a one-pot manner for the application in supercapacitor. In this approach, the formation of the NiHN shells and the dissolution of the melamine-formaldehyde (MF) template particles occur simultaneously and successively under a solvothermal condition with time. It is found that the nickel precursors can protonate the solvent, declining the pH and further causing the dissolution of the MF particles. Meanwhile, the nickel precursors transform into NiHN nanosheets that self-assemble into hierarchical shells exclusively at the surface of the MF particles. With the reactions proceeding, the NiHNHCP are yielded ultimately. These NiHNHCP are characterized with superior electrochemical performance, making them practically useful in the application of supercapacitor.

Risk of bias in the included trials as assessed by the Cochrane risk of bias assessment tool. (DOCX 14 kb)

Formulas used in the current study. (DOCX 16 kb)

The Study characteristics of included trials about JAK inhibitors. (DOCX 42 kb)

Search algorithm from Medline. (DOCX 16 kb)