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Mimicking the nitric oxide (NO)-release and glycocalyx functions of native vascular endothelium on cardiovascular stent surfaces has been demonstrated to reduce in-stent restenosis (ISR) effectively. However, the practical performance of such an endothelium-mimicking surfaces is strictly limited by the durability of both NO release and bioactivity of the glycocalyx component. Herein, we present a mussel-inspired amine-bearing adhesive coating able to firmly tether the NO-generating species (e.g., Cu-DOTA coordination complex) and glycocalyx-like component (e.g., heparin) to create a durable endothelium-mimicking surface. The stent surface was firstly coated with polydopamine (pDA), followed by a surface chemical cross-link with polyamine (pAM) to form a durable pAMDA coating. Using a stepwise grafting strategy, Cu-DOTA and heparin were covalently grafted on the pAMDA-coated stent based on carbodiimide chemistry. Owing to both the high chemical stability of the pAMDA coating and covalent immobilization manner of the molecules, this proposed strategy could provide 62.4% bioactivity retention ratio of heparin, meanwhile persistently generate NO at physiological level from 5.9 ± 0.3 to 4.8 ± 0.4 × 10−10 mol cm−2 min−1 in 1 month. As a result, the functionalized vascular stent showed long-term endothelium-mimicking physiological effects on inhibition of thrombosis, inflammation, and intimal hyperplasia, enhanced re-endothelialization, and hence efficiently reduced ISR., Graphical abstract Image 1, Highlights • A durable endothelium-mimicking coating was developed for surface bioengineering of cardiovascular stents. • The durable endothelium-mimicking surface was realized by stepwise grafting of Cu-DOTA and heparin on a robust coating. • The durable endothelium-mimicking coating endows the vascular stents with ability to dramatically reduce restenosis.

Tremendous demands for highly sensitive and stable seawater salinometers have motivated intensive research on advanced electrode materials. Boron-doped diamond (BDD) is attractive in terms of its high mechanical stability and chemical inertness, but is usually hindered by its low double-layer capacitance (Cdl) for seawater salinity detection. Here, inspired by the principle of oxygen-terminated BDD electrode endowing higher Cdl than hydrogen-terminated surface, we introduce the oxygen terminated surface by oxygen plasma or reactive ion etch (RIE), and the fabricated oxygen terminated BDD electrodes demonstrate high sensitivity and long-term stability in seawater salinity detection comparing with the hydrogen terminated BDD electrodes. Significantly, the as-fabricated O-BDD-RIE electrodes not only show remarkable enhanced response even better than the commercial platinum black electrodes but also display long-time stability which is weekly verified by continuous monitor for 90 days. The outstanding performance of the oxygen terminated BDD electrodes can be ascribed to the enhancement of C-O surface functional group on Cdl. In addition, a comprehensive analysis of effective electroactive surface area (EASA) and Cdl proves that the surface oxygen is the major factor for the improved Cdl. In summary, the excellent oxygen terminated BDD electrodes promise potential application in seawater salinity detection.

The TiO2-Ag hybrid nanofluids were prepared by diluting high-concentration nanofluids and adding Span80 as surfactants. The stability of nanofluids was studied by taking photos of the nanofluids with storage time of 0–30 days. The thermal conductivity and dynamic viscosity were measured at different volume fraction, temperature and ultrasonication time. The results showed that compared with the base fluid, the maximum enhancement of thermal conductivity was 9.98%, and the maximum dynamic viscosity ratio was 2.78. And ultrasonication treatment is recommended to alleviate the sedimentation of nanofluids. Then, two artificial neural networks (ANNs) were established and the size of the networks was optimized according to the relative error to improve the ability to predict the thermal properties of nanofluids. The results show that the maximum relative error of the prediction of thermal conductivity and dynamic viscosity is 1.44% and 3.54%, respectively, which is beneficial to saving experiment time and cost.

Hybrid perovskites are emerging as a promising, high-performance luminescent material; however, the technological challenges associated with generating high-resolution, free-form perovskite structures remain unresolved, limiting innovation in optoelectronic devices. Here, we report nanoscale three-dimensional (3D) printing of colored perovskite pixels with programmed dimensions, placements, and emission characteristics. Notably, a meniscus comprising femtoliters of ink is used to guide a highly confined, out-of-plane crystallization process, which generates 3D red, green, and blue (RGB) perovskite nanopixels with ultrahigh integration density. We show that the 3D form of these nanopixels enhances their emission brightness without sacrificing their lateral resolution, thereby enabling the fabrication of high-resolution displays with improved brightness. Furthermore, 3D pixels can store and encode additional information into their vertical heights, providing multilevel security against counterfeiting. The proof-of-concept experiments demonstrate the potential of 3D printing to become a platform for the manufacture of smart, high-performance photonic devices without design restrictions.

The dependence of interfacial contact resistance (ICR) on contact materials between cathode and interconnect is systematically studied under both isothermal oxidation and thermal cycling conditions. Three kinds of cathode current-collecting layer (CCCL) are used, (La,Sr) (Co,Fe)O3 (LSCF), LSCF+10%Ag, and Ag, and tested in a SUS430/CCCL/SUS430 sandwich structure to simulate the actual operation of the solid oxide fuel cells (SOFCs). Experimental results show that the ICR of LSCF+10%Ag exhibits the smallest value, in comparison with the specimens with LSCF and Ag paste, as well as the sample without a CCCL. For LSCF+10%Ag contact, the ICR increases from 0.0069 mΩ cm2 to 3.74 mΩ cm2 under an isothermal condition for 150 h, then increases from 3.74 mΩ cm2 to 10.79 mΩ cm2 after 15 thermal cycles. This work provides information for the understanding of possible mechanisms of performance degradation of SOFCs.

Application of extracorporeal circuits and indwelling medical devices has saved many lives. However, it is accompanied with two major complications: thrombosis and infection. To address this issue, we apply therapeutic nitric oxide gas (NO) and antibacterial peptide for synergistically tailoring such devices for surface anti-thrombogenic and antifouling dual functions. Such functional surface is realized by stepwise conjugation of NO-generating compound of 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) chelated copper ions (Cu-DOTA) and dibenzylcyclooctyne- (DBCO-) modified antimicrobial peptide based on carbodiimide and click chemistry respectively. The integration of peptide and Cu-DOTA grants the modified surface the ability to not only efficiently inhibit bacterial growth, but also catalytically generate NO from endogenous s-nitrosothiols (RSNO) to reduce adhesion and activation of platelets, preventing the formation of thrombus. We envision that the stepwise synergistic modification strategy by using anticoagulant NO and antibacterial peptide would facilitate the surface multifunctional engineering of extracorporeal circuits and indwelling medical devices, with reduced clinical complications associated with thrombosis and infection., Graphical abstract Image 1, Highlights • We report a bionic surface strategy for blood-contacting devices by integrating anti-thrombogenic and anti-microbial dual functions. Here, we engineer an endothelium-mimicking surface by combination of the nitric oxide (NO)-generating property and anti-microbial functions of a healthy endothelium, in which the generated gas signal molecule NO and the anti-microbial peptide (AMP) jointly provide synergistic effects against thrombogenicity and biofouling. • An endothelium-bionic surface strategy is proposed for tailoring surface multi-functionalities. • Carbodiimide and click chemistries were used for realizing synergistic tethering of NO-generating species and bio-clickable antimicrobial peptide. • The integration of NO and antimicrobial peptide imparts the tubing surface with anti-thrombogenic and anti-fouling dual functions. The integration of NO releasing and AMP tethering endows the tubing surface with significant anti-thrombogenic and anti-fouling properties. We envision that this bio-inspired surface engineering strategy will provide a promising solution to address the clinical issues.

Pre-pregnancy body mass index and weight gain management are associated with pregnancy outcomes in expecting women. Poor gestational weight gain (GWG) management could increase the risk of adverse complications. These risks can be alleviated by lifestyle-based interventions if an undesired GWG trend is detected early on in the pregnancy. Current literature lacks analysis of gestational weight gain data and tracking the pregnancy over time. In this work, we collected longitudinal gestational weight gain data from women during their pregnancy and model their weight measurements to predict the end-of-pregnancy weight gain and classify it in accordance with the medically recommended guidelines. The measurement frequency of the weights is often very variable such that segments of data can be missing and the need to predict early utilising few data points complicates data modelling. We propose a Bayesian approach to forecast weight gain while effectively dealing with the limited data availability for early prediction. We validate on diverse populations from Europe and China. We show that utilising individual’s data only up to mid-way through the pregnancy, our approach produces mean absolute errors of 2.45 kgs and 2.82 kgs in forecasting end-of-pregnancy weight gain on these populations respectively, whereas the best of state-of-the-art yields 8.17 and 6.60 kgs on respective populations. The proposed method can serve as a tool to keep track of an individual’s pregnancy and achieve GWG goals, thus supporting the prevention of excessive or insufficient weight gain during pregnancy.

Titanium dioxide (TiO2) has a long history of application in blood contact materials, but it often suffers from insufficient anticoagulant properties. Recently, we have revealed the photocatalytic effect of TiO2 also induces anticoagulant properties. However, for long-term vascular implant devices such as vascular stents, besides anticoagulation, also anti-inflammatory, anti-hyperplastic properties, and the ability to support endothelial repair, are desired. To meet these requirements, here, we immobilized silver nanoparticles (AgNPs) on the surface of TiO2 nanotubes (TiO2-NTs) to obtain a composite material with enhanced photo-induced anticoagulant property and improvement of the other requested properties. The photo-functionalized TiO2-NTs showed protein-fouling resistance, causing the anticoagulant property and the ability to suppress cell adhesion. The immobilized AgNPs increased the photocatalytic activity of TiO2-NTs to enhances its photo-induced anticoagulant property. The AgNP density was optimized to endow the TiO2-NTs with anti-inflammatory property, a strong inhibitory effect on smooth muscle cells (SMCs), and low toxicity to endothelial cells (ECs). The in vivo test indicated that the photofunctionalized composite material achieved outstanding biocompatibility in vasculature via the synergy of photo-functionalized TiO2-NTs and the multifunctional AgNPs, and therefore has enormous potential in the field of cardiovascular implant devices. Our research could be a useful reference for further designing of multifunctional TiO2 materials with high vascular biocompatibility., Graphical abstract Image 1, Highlights • Photo-functionalized TiO2NTs@Ag composites showed excellent vascular compatibility. • UV irradiation greatly improved the anticoagulant properties of the composites. • Moderately loaded AgNPs strongly inhibited SMCs and MAs, but weakly inhibited ECs.

Thanks to its simplicity, versatility, and secondary reactivity, dopamine self-polymerized coatings (pDA) have been widely used in surface modification of biomaterials, but the limitation in secondary molecular grafting and the high roughness restrain their application in some special scenarios. Therefore, some other catecholamine coatings analog to pDA have attracted more and more attention, including the smoother poly-norepinephrine coating (pNE), and the poly-levodopa coating (pLD) containing additional carboxyl groups. However, the lack of a systematic comparison of the properties, especially the biological properties of the above three catecholamine coatings, makes it difficult to give a guiding opinion on the application scenarios of different coatings. Herein, we systematically studied the physical, chemical, and biological properties of the three catecholamine coatings, and explored the feasibility of their application for the modification of biomaterials, especially cardiovascular materials. Among them, the pDA coating was the roughest, with the largest amount of amino and phenolic hydroxyl groups for molecule grafting, and induced the strongest platelet adhesion and activation. The pLD coating was the thinnest and most hydrophilic but triggered the strongest inflammatory response. The pNE coating was the smoothest, with the best hemocompatibility and histocompatibility, and with the strongest cell selectivity of promoting the proliferation of endothelial cells while inhibiting the proliferation of smooth muscle cells. To sum up, the pNE coating may be a better choice for the surface modification of cardiovascular materials, especially those for vascular stents and grafts, but it is still not widely recognized., Graphical abstract Image 1, Highlights • Systematically studied the physico-chemical and biological properties of poly-dopamine, levodopa and norepinephrine coatings. • The poly-norepinephrine coating (pNE) has the best hemo/histocompatibility and vascular cell selectivity. • Indicating that pNE coating may be more suitable for modification of blood contacting materials than others.

This work presents an audio watermarking scheme using minimum-amplitude scaling on the optimized lowest-frequency coefficients in the wavelet domain. Signal-to-noise ratio (SNR), bit-error-rate (BER) and Perceptual Evaluation of Audio Quality (PEAQ) are commonly utilized performance indexes in measuring the fidelity, robustness and quality of watermarking algorithms. However, there is a tradeoff relationship between audio quality and robustness. To overcome the drawback, this paper aims in proposing an optimization-based scaling scheme using optimal modification of low-frequency amplitude in the wavelet domain. A function connecting the multi-coefficients, composed of arbitrary scaling on the lowest DWT coefficients, and the group SNR of these coefficient is derived. Karush-Kuhn-Tucker (KKT) theorem and minimum length play two essential roles to obtain the optimal modification of low-frequency amplitude with optimal scaling factors. Furthermore, the almost invariant feature of these optimized scaling factors hold demonstrates resistance to amplitude modification manipulation. To practically evaluate the watermarked audio quality, an objective measurement using the PEAQ is also performed as well. Experimental results confirm that the embedded audio in the proposed method has high SNR, low BER, and good PEAQ, indicating strong robustness against various attacks, such as re-sampling, amplitude modification, and mp3 compression.

Polyurethanes are widely used in interventional devices due to the excellent physicochemical property. However, non-specific adhesion and severe inflammatory response of ordinary polyurethanes may lead to severe complications of intravenous devices. Herein, a novel phospholipid-based polycarbonate urethanes (PCUs) were developed via two-step solution polymerization by direct synthesis based on functional raw materials. Furthermore, PCUs were coated on biomedical metal sheets to construct biomimetic anti-fouling surface. The results of stress–strain curves exhibited excellent tensile properties of PCUs films. Differential scanning calorimetry results indicated that the microphase separation of such PCUs polymers could be well regulated by adjusting the formulation of chain extender, leading to different biological response. In vitro blood compatibility tests including bovine serum albumin adsorption, fibrinogen adsorption and denaturation, platelet adhesion and whole-blood experiment showed superior performance in inhibition non-specific adhesion of PCUs samples. Endothelial cells and smooth muscle cells culture tests further revealed a good anti-cell adhesion ability. Finally, animal experiments including ex vivo blood circulation and subcutaneous inflammation animal experiments indicated a strong ability in anti-thrombosis and histocompatibility. These results high light the strong anti-adhesion property of phospholipid-based PCUs films, which may be applied to the blood-contacting implants such as intravenous catheter or antithrombotic surface in the future.

The effect of the surface wettability of plasma-modified vertical Si nanowire array on the bio-fouling performance has been investigated. The Si nanowires prepared by a metal-assisted chemical etching technique exhibit a super-hydrophilic surface. The treatment in CH4/H2 gas plasma environment leads to the decoration of graphite and diamond nanoparticles around Si nanowires. The detailed interface between graphite/diamond and Si nanowire was characterized by HRTEM technique. These surface-modified nanowire samples show an increased water contact angle with ultrananocrystalline diamond decorated ones being superhydrophobic. The immersion test in chlorella solution reveals that the diamond-coated Si nanowires possess the least attachment of chlorella in comparison with other Si nanowires. This result confirms that the coating of Si nanowires with diamond nanoparticles shows the best behavior in anti-biofouling. Importantly, this work provides a method fabricated super-hydrophobic surface for the application of biofouling prevention.

The rapid re-endothelialization of the vascular stent surface is desirable for preventing thrombosis or reducing restenosis. Many biological factors that promote the biological behavior of endothelial cells have been used for the surface modification of stents. Vascular endothelial growth factor (VEGF), which plays an important role in angiogenesis, induces strong vascular growth. In this study, we investigated different VEGF concentrations (50 to 500 ng/ml) to determine the optimum concentration for biocompatibility. First, VEGF-loaded heparin/poly-l-lysine (Hep-PLL) nanoparticles were created by electrostatic interactions. Then, the VEGF-loaded nanoparticles were immobilized on dopamine-coated 316 L stainless steel (SS) surfaces. The physical and chemical properties of the modified surface were characterized and the biocompatibility was evaluated in vitro. The results indicated that the VEGF-loaded nanoparticles were immobilized successfully on the 316LSS surface, as evidenced by the results of Alcian Blue staining and water contact angle (WCA) measurements. The low platelet adhesion and activation indicated that the modified surfaces had good blood compatibility. The modified surfaces showed a good inhibitory effect on smooth muscle cells, indicating that they inhibited tissue hyperplasia. In addition, the modified surfaces significantly promoted endothelial cell adhesion, proliferation, migration, and biological activity, especially VEGF concentration was 350 ng/ml (NPV350). The optical VEGF concentration of the surface modified Hep-PLL nanoparticles was 350 ng/ml. The proposed method shows promise for potential applications for cardiovascular devices.

Implantation of a drug-eluting stent is the most common treatment method for patients with cardiovascular atherosclerosis. However, this treatment may delay re-endothelialization, and the drug polymer-coated stent may induce thrombosis months after a stent implantation. The development of polymer-free drug-eluting stents is a promising approach to overcome these shortcomings. Titanium dioxide nanotubes (TiO2-NTs) are excellent drug carriers and have been considered as a potential material for polymer-free drug-eluting stents. However, TiO2-NTs reportedly induce severe blood clotting, which is a significant shortcoming for use as a stent. Vascular stents must be compatible with blood and must have antibacterial, anti-inflammatory, and selective inhibitory activities in the abnormal hyperplasia of smooth muscle cells, instead of delaying the re-endothelialization of endothelial cells. To meet these requirements, we presented a composite material that featured ultraviolet (UV) irradiation of TiO2-NTs-containing silver nanoparticles (AgNPs). The AgNPs were loaded in the lumen of TiO2-NTs as a representative compound to suppress the inflammatory response and hyperplasia. UV irradiation was performed as a novel method to improve the anticoagulant ability of the AgNP-loaded TiO2-NTs. The chemical state and biocompatibility of the UV-TiO2-NTs@AgNPs were evaluated. UV irradiation strongly improved the anticoagulant ability of the TiO2-NTs and moderated the release of Ag+ from AgNPs, which selectively suppressed the inflammatory response and hyperplasia. Furthermore, the UV-TiO2-NTs@AgNPs-2 displayed enhanced biocompatibility evidenced by the inhibition of platelet adhesion, bactericidal activity, selective suppression of the smooth muscle cell proliferation, and inhibition of the adhesion of macrophages. The collective findings indicate the potential of the photofunctionalized TiO2-NTs loaded with AgNPs as a material for polymer-free drug-eluting stents.

Integration of two or more biomolecules with synergetic and complementary effects on a material surface can help to obtain multi-functions for various biomedical applications. However, the amounts of biomolecules integrated and their physiological functions are compromised due to the limited surface anchoring sites. Herein, we propose a novel concept of film engineering strategy “from surface to bulk synergetic modification”. This new concept is realized by employing the surface amine groups of plasma polymerized allylamine (PPAm) film for grafting a molecule e.g., thrombin inhibitor, bivalirudin (BVLD), meanwhile its bulk amine groups is used as a universal depot for storing and releasing therapeutic nitric oxide (NO) gas as supplement to the functions of BVLD. It is demonstrated that such a “from surface to bulk synergetic modification” film engineering can impart the modified-substrates with anti-platelet and anti-coagulant dual functions, giving rise to a highly endothelium-mimetic thromboresistant property. We believe that our research provides a very promising strategy to deliver multifunctional surface versatilely that require NO release in combination with other properties, which will find broad biomedical applications in blood-contacting devices, and et al. Moreover, it also provides a brand-new film engineering strategy for tailoring surface multi-functionalities of a wide range of materials., Graphical abstract Image 1, Highlights • A concept of “from surface to bulk synergetic modification” is proposed for tailoring surface multi-functionalities. • The surface amine groups of plasma polymerized allylamine (PPAm) film were used for grafting bivalirudin. • The bulk amine groups of PPAm film is utilized as the universal depots for storing and releasing nitric oxide.

The integration of sp2-/sp3-bonded carbon has aroused increasing attention on attaining a great electron field emission (EFE) performance. Herein, a novel hierarchical diamond@carbon nanowalls/diam...

NO is the earliest discovered gas signal molecule which is produced by normal healthy endothelial cells, and it has many functions, such as maintaining cardiovascular homeostasis, regulating vasodilation, inhibiting intimal hyperplasia and preventing atherosclerosis in the blood system. Insufficient NO release is often observed in the pathological environment, for instance atherosclerosis. It was discovered that NO could be released from the human endogenous NO donor by many compounds, and these methods can be used for the treatment of certain diseases in the blood system. In this work, a series of copper-loaded polydopamine (PDA) coatings were produced through self-polymerization time for 24, 48 and 72 h. The chemical composition and structure, coating thickness and hydrophilicity of the different copper-loaded PDA coatings surfaces were characterized by phenol hydroxyl quantitative, X-ray photoelectron spectroscopy, ellipsometry atomic force microscopy and water contact angles. The results indicate that the thickness and the surface phenolic hydroxyl density of the PDA coatings increased with the polymerization time.This copper-loaded coating has glutathione peroxidase-like activity, and it has the capability of catalyzing NO releasing from GSNO. The surface of the coating showed desirable hemocompatibility, the adhesion and activation of platelets were inhibited on the copper-loaded coatings. At the same time, the formation of the thrombosis was also suppressed. These copper-loaded PDA coatings could provide a promising platform for the development of blood contact materials.

This paper conducts a new investigation of air purification with total heat recovery based on nanofluids for the first time to realize the synergistic application of nanofluids to the heat and mass transfer as well as the photocatalysis and sterilization fields. To explore the feasibility of the new application, the stable TiO2 nanofluids were obtained by a post-treated optimized preparation method. Then the experimental device is built to investigate the formaldehyde and total volatile organic compounds (TVOC) purification as well as sterilization. At last, the heat recovery characteristics of nanofluids are indirectly investigated by testing the gas-liquid bubbling heat transfer behaviour. The results show the post-treated method can improve the dispersion stability of nanofluids. The nanofluid system has efficient effects on air purification and sterilization for both fungi and bacteria. The nanofluids have higher gas-liquid bubbling heat transfer performance than water which increased as the particle loading.

Optical image computing, such as spatial differentiation, logical transform, and addition-subtraction operation, is of great importance to signal enhancement, transform, and extraction, but such nonlinear methods are restrained in incoherent or scattering imaging. Here, the logical white-light image reconstruction, as an optical image computing method for incoherent and scattered images, is proposed by monitoring a seeded potential in variable detection planes. The weak white-light signals collectively seed a potential at the expense of scattering noise based on seeded modulation instability in a photorefractive crystal. Then the logical image operation is achieved by sensitively probing the seeded potential and recording the intensity distribution of the probe beam in different detection planes. The proposed method has a strong ability of ballistic signal recording, reproduction, and reversal. The numerical and experimental results show a new physical phenomena in which the indirect interaction between light waves through a seeded potential is presented in different forms. The nonlinear method is proved to effectively operate pure images, the images scattered by a rotating diffuser, and the images scattered by fogs whether under back lighting or under front lighting. Our work suggests an alternative method for all-optical image processing, recovery, and computing.

Silicon vacancy (SiV) centers in CVD-deposited nanodiamond particles or films always exhibit a photoluminescent (PL)-quenching behavior. Herein, in order to overcome this issue, air annealing of nanocrystalline diamond (NCD) films with uniform doping of Si atoms is employed to improve the PL emission efficiency of SiV centers. Without severe mass loss in diamond, SiV centers exhibit an increased PL emission intensity at 738 nm with an increased annealing temperature and time. In comparison to the untreated film, the maximum PL enhancement reaches about 200 and 1473 folds when the NCD films are annealed at 600 °C for 60 min and 700 °C for 20 min, respectively. Such giant increase in SiV PL emission is mainly attributed to the transition of diamond surface from hydrogen to oxygen termination together with the optimized crystalline quality of the annealed films, as confirmed by the HRTEM, Raman and XPS measurements. A schematic model based on the theory of surface band bending is proposed to elucidate the mechanism of the SiV PL enhancement in oxygen-terminated NCD films: a near-surface light trap layer formed in hydrogen-terminated NCD is converted during the oxidation process, leading to the additional collection of SiV PL emission from the inner layer.

Nowadays, the stability and heat transfer properties of nanofluids have been extensively studied. However, for the practical application, the dynamic stability, sedimentation, and fouling characteristics are also important issues. Whether nanofluids can maintain stable heat transfer characteristics during intermittent operation in the system is also a worthwhile issue. In this paper, the dynamic stability, sedimentation, and fouling characteristics as well as the time-dependent heat transfer characteristics of TiO2 and CNT nanofluids are investigated sequentially. The results show that compared with static condition, the dispersion stability of nanofluids is much better, and the sedimentation and fouling on solid surface are much less in dynamic condition. For the nanofluids in this paper, the sedimentation and fouling on solid surface are loose and can easily washed out after slight flushing. Rough surfaces are easier to adsorb the nanoparticles sedimentation and form fouling, but it can be greatly removed using ultrasonication. Long-term shutdown reduces the convective heat transfer enhancement of nanofluids, but it can be well restored after the action of ultrasonication.

This article experimentally investigates the cyclic behavior of ultra high performance concrete–filled steel tube beam-columns. A total of eight specimens were tested. The considered parameters were the axial load ratio and steel ratio. The results showed that all ultra high performance concrete–filled steel tube beam-columns had a very good cyclic behavior without significant pinching. Increasing the axial load ratio results in the decrease of strength and ductility, but it has no obvious influence on the initial flexural stiffness. Reducing the steel ratio results in the decrease of the strength, stiffness and ductility, and energy dissipation capacity.

In recent years, the natural ingredients are in high demand in formulating the cosmetic products. Seaweed polysaccharides signify the attractive natural ingredient with a wide range of functional properties that are expected for cosmeceutical formulations. The present work aimed to study the skin protection ability of polysaccharides extracted from Sargassum vachellianum (SvP), Sargassum horneri (ShoP) and Sargassum hemiphyllum (SheP). The extracted crude polysaccharides were characterized by HPLC and FTIR, which revealed that the polysaccharides are fucose-containing sulfated polysaccharides. Skin whitening and anti-wrinkling activity were analyzed by the ability to inhibit tyrosinase and elastase. The results revealed that the ShoP showed maximum tyrosinase inhibition (64.72 ± 0.46%) and SvP exhibited considerable elastase inhibition (30.12 ± 0.33%). The maximum moisture absorption (79.7 ± 0.62%) and retention (68.99 ± 0.64%) ability were observed in ShoP. The antioxidant activity was estimated by DPPH, superoxide radical scavenging, reducing power and total antioxidant activity. All the tested polysaccharides showed antioxidant activity in a dose-dependent manner, among them ShoP exhibited maximum total antioxidant (80.93 ± 0.17%) and superoxide radical scavenging activity (67.4 ± 0.42%) whereas SheP showed maximum DPPH radical scavenging activity (74.56 ± 0.10%). Therefore, the present study indicates the potential of polysaccharides, ShoP, SvP and SheP as a promising cosmetic ingredient in cosmeceuticals.

The present study aims at enhancing the thermal performance of SAE 50 engine oil by adding zinc oxide nanoparticles. The investigations are performed in the thermal range of 25 to 55 °C and at the volume fractions of 0.125 to 1.5%. In this regard, first, the characterization of nanoparticles was performed to examine their surface and atomic structure. Moreover, following the manufacture of the nano-lubricant, its stability was investigated by the DLS test. After ensuring the results of nano-lubricant stability, different samples were prepared according to the variations in volume fraction, followed by the experimental measurement of the thermal conductivity of nano-lubricant. The obtained results revealed an ascending trend in thermal conductivity by increasing temperature and concentration. The maximum thermal conductivity enhancement was 8.74%. Based on the experimental results, a sharply precise relation was proposed to predict the ratio of nano-lubricant thermal conductivity to that of the tested base fluid.

Environmentally responsive polymer films have received much attention, but the stability of such films and the sensitivity of the response still have to be improved. The preparation of responsive films for low pH changes still faces challenges. In this study, catechol groups were used to functionalize chitosan and hyaluronic acid for mussel-inspired, catechol based adhesion. The modified chitosan and the modified hyaluronic acid were deposited in a layer-by-layer manner. The chemical properties of the compounds and surface properties of the coatings were characterized by UV, IR, scanning electron microscopy and water contact angles. The assembly and stability of the film were investigated in situ using quartz crystal microbalance (QCM-D). The film had improved stability compared to the native polymers and it showed reversible pH-dependent swelling and shrinkage. The film was loaded with a drug and placed in PBS solutions of different pH for several days, and the amount of drug released by the drug-loaded film was different under different pH environments. This provides ideas for the intelligent application in materials science and biology, and has broad prospects in drug delivery systems and tissue engineering.

The effects of surface adsorption of bovine serum albumin (BSA) and human gamma-globulin (HGG) on the tribological performance of a DLC film were investigated using a quartz crystal microbalance with dissipation (QCM-D), a ball-on-disk reciprocating tribometer, and a three-electrode electrochemical cell. The results showed that the wear depth in the BSA solution was higher than that in the HGG solution. In the HGG solution, the HGG-adsorbed layer could act as a lubricating layer and protect the DLC film from wear. The wear volume of DLC film in BSA and HGG mixture solution was higher than that in single HGG solution. This may be because the BSA molecules inhibit the formation of HGG adsorbed layer during sliding.

We have developed a sensitive cryogenic second-harmonic generation microscopy to study a van der Waals antiferromagnet ${\mathrm{MnPS}}_{3}$. We find that long-range N\'eel antiferromagnetic order develops from the bulk crystal down to the bilayer, while it is absent in the monolayer. Before entering the long-range antiferromagnetic ordered phase in all samples, an upturn of the second harmonic generation below 200 K indicates the formation of the short-range order and magnetoelastic coupling. We also directly image the two antiphase (180\ifmmode^\circ\else\textdegree\fi{}) antiferromagnetic domains and thermally induced domain switching down to bilayer. An anomalous mirror symmetry breaking shows up in samples thinner than ten layers for the temperature both above and below the N\'eel temperature, which indicates a structural change in few-layer samples. Minimal change of the second harmonic generation polar patterns in strain tuning experiments indicate that the symmetry crossover at ten layers is most likely an intrinsic property of ${\mathrm{MnPS}}_{3}$ instead of an extrinsic origin of substrate-induced strain. Our results show that second harmonic generation microscopy is a direct tool for studying antiferromagnetic domains in atomically thin materials, and opens a new way to study two-dimensional antiferromagnets.

Cadmium (Cd) and arsenic (As) contamination in paddy soils poses serious health risks to humans. The accumulation of Cd and As in rice (Oryza sativa L.) depends on their bioavailability, which is affected by soil physicochemical properties and soil microbial activities. However, little is known about the intricate interplay between rice plants and their rhizosphere microbes during the uptake of Cd and As. In this study, different bacterial communities were established by sterilizing paddy soils with γ-radiation. A pot experiment using two paddy soils with different levels of contamination was conducted to explore how the bacterial community composition affects Cd and As accumulation in rice plants. The results showed that the sterilization treatment substantially changed the bacterial composition in the rhizosphere, and significantly increased the grain yield (by 33.5–38.3%). The sterilization treatment resulted in significantly decreased concentrations of Cd (by 18.2–38.7%) and As (by 20.3–36.7%) in the grain, straw, and root of rice plants. The accumulation of Cd and As in rice plants was negatively correlated with the relative abundance of sulfate-reducing bacteria and iron-oxidizing bacteria in the rhizosphere. Other specific taxa associated with the accumulation of Cd and As in rice plants were also identified. Our results suggest that regulating the composition of the rhizosphere bacterial community could simultaneously reduce Cd and As accumulation in rice grain and increase the grain yield. These results would be useful for developing strategies to cultivate safe rice crops in areas contaminated with Cd and As.

Conventional in vitro methods for biological evaluation of intra-arterial devices such as stents fail to accurately predict cytotoxicity and remodeling events. An ex vivo flow-tunable vascular bioreactor system (VesselBRx), comprising intra- and extra-luminal monitoring capabilities, addresses these limitations. VesselBRx mimics the in vivo physiological, hyperplastic, and cytocompatibility events of absorbable magnesium (Mg)-based stents in ex vivo stent-treated porcine and human coronary arteries, with in-situ and real-time monitoring of local stent degradation effects. Unlike conventional, static cell culture, the VesselBRx perfusion system eliminates unphysiologically high intracellular Mg(2+) concentrations and localized O(2) consumption resulting from stent degradation. Whereas static stented arteries exhibited only 20.1% cell viability and upregulated apoptosis, necrosis, metallic ion, and hypoxia-related gene signatures, stented arteries in VesselBRx showed almost identical cell viability to in vivo rabbit models (~94.0%). Hyperplastic intimal remodeling developed in unstented arteries subjected to low shear stress, but was inhibited by Mg-based stents in VesselBRx, similarly to in vivo. VesselBRx represents a critical advance from the current static culture standard of testing absorbable vascular implants.

The photochemical reactivity of humic substances plays a critical role in the global carbon cycle, and influences the toxicity, mobility, and bioavailability of contaminants by altering their molecular structure and the mineralization of organic carbon to CO2. Here, we examined the simulated irradiation process of Chinese standard fulvic acid (FA) and humic acid (HA) by using excitation-emission matrix fluorescence combined with fluorescence regional integration (FRI), parallel factor (PARAFAC) analysis, and kinetic models. Humic-like and fulvic-like materials were the main materials (constituting more than 90%) of both FA and HA, according to the FRI analysis. Four components were identified by the PARAFAC analysis: fulvic-like components composed of both carboxylic-like and phenolic-like chromophores (C1), terrestrial humic-like components primarily composed of carboxylic-like chromophores (C2), microbial humic-like overwhelming composed of phenolic-like fluorophores (C3), and protein-like components (C4). After irradiation for 72 h, the maximum fluorescence intensity (Fmax) of C1 and C2 of FA was reduced to 36.01–58.34%, while the Fmax of C3 of both FA and HA also decreased to 0–9.63%. By contrast, for HA, the Fmax of its C1 and C2 increased to 236.18–294.77% when irradiated for 72 h due to greater aromaticity and photorefractive tendencies. The first-order kinetic model (R2 = 0.908–0.990) fitted better than zero-order kinetic model (R2 = 0–0.754) for the C1, C2, and C3, of both FA and HA, during their photochemical reactivity. The photodegradation rate constant (k1) of C1 had values (0.105 for FA; 0.154 for HA) that surpassed those of C2 (0.059 for FA, 0.079 for HA) and C3 (0.079 for both FA and HA) based on the first-order kinetic model. The half-life times of C1, C2, and C3 ranged from 6.61–11.77 h to 4.50–8.81 h for FA and HA, respectively. Combining an excitation-emission matrix with FRI and PARAFAC analyses is a powerful approach for elucidating changes to humic substances during their irradiation, which is helpful for predicting the environmental toxicity of contaminants in natural ecosystems.

Background: Antinuclear antibody pattern recognition is vital for autoimmune disease diagnosis but labor-intensive for manual interpretation. To develop an automated pattern recognition system, we established machine learning models based on the International Consensus on Antinuclear Antibody Patterns (ICAP) at a competent level, mixed patterns recognition, and evaluated their consistency with human reading. Methods: 51,694 human epithelial cells (HEp-2) cell images with patterns assigned by experienced medical technologists collected in a medical center were used to train six machine learning algorithms and were compared by their performance. Next, we choose the best performing model to test the consistency with five experienced readers and two beginners. Results: The mean F1 score in each classification of the best performing model was 0.86 evaluated by Testing Data 1. For the inter-observer agreement test on Testing Data 2, the average agreement was 0.849 (κ) among five experienced readers, 0.844 between the best performing model and experienced readers, 0.528 between experienced readers and beginners. The results indicate that the proposed model outperformed beginners and achieved an excellent agreement with experienced readers. Conclusions: This study demonstrated that the developed model could reach an excellent agreement with experienced human readers using machine learning methods.

A series of d10 based metal-organic frameworks (MOFs), namely, [Cd2(dpc)(bipy)(H2O)3]n (Ⅰ), {[Cd2(dpc)(bib)(H2O)]·H2O}n (Ⅱ), {[Cd2(dpc)(bitb)1.5(H2O)2]·H2O}n (Ⅲ) (H4dpc = 2-(3′,4′-dicarboxylphenoxy)isophthalic acid, bipy = 4,4′-dipyridyl, bib = 1,4-bis (1-imidazolyl)benzene, bitb = 1,4-bis (imidazol-1-ylmethyl)benzene) have been designed and successfully synthesized using a flexible tetrabasic carboxylic acid along with three ancillary ligands under hydrothermal conditions, which exhibit structural diversities of targeted Cd-MOFs. Single-crystal X-ray diffraction analysis reveals that they contain building units of {CdN1O6} and {CdN1O5} (for I), {CdN1O5} (for II), as well as {CdN2O4} and {CdN5O1} (for Ⅲ), based on which to assemble microporous three-dimensional (3D) frameworks via covalent bonds and/or hydrogen bonds using multiple coordination modes of H4dpc ligand and auxiliary linkers. The solid-state luminescence performances of these Cd-MOFs were investigated at ambient temperature. Furthermore, luminescent sensing responses of Ⅰ-Ⅲ to amino acids and metal cations were systematically explored. Notably, Ⅰ and II may act as potential dual-functional luminescent sensors for Aspartic acid and Cu2+ cations as well as Aspartic acid and Fe3+ cations with high selectivity and sensitivity in aqueous solutions, respectively. The mechanisms of the quenching effect and sensing properties of the as-synthesized Cd-MOFs have also been discussed in this report.

In this work, we demonstrate a simple method to prepare carbon nanofiber (CNF) with multilevel gradient porous structure derived from polyvinylidene fluoride (PVDF)- polyvinyl pyrrolidone (PVP) /PVP core-shell nanofiber. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) have confirmed that the as-prepared CNF contains a hollow channel embraced by mesoporous and microporous structures. Its specific surface area reaches to 1084 m2/g with the mesoporous volume contribution of 59%. The as-prepared porous CNF shows a high capacitance of 331 F/g at 1 A/g and 99.6% capacitance retention after 10,000 cycles at 5 A/g, which is better than the corresponding CNF with irregularly arranged hierarchical pores. The all-solid-state symmetric supercapacitor assembled using the as-prepared porous CNF as electrodes exhibits an excellent high specific capacitance of 147.4F/g at 1 A/g with a high energy density of 13.1 W h/kg. The capacitance retention still maintains at 89.2% after 2000 cycles at a current density of 5 A/g. Meanwhile, the as-prepared porous CNF also shows a high CO2 adsorption uptake, 5.08 mmol/g at 0 °C and 1 bar. The possible reason and mechanism have been discussed.

Agricultural terraces are important for agricultural production and soil-and-water conservation. They comprise treads and risers that require manual construction and maintenance. If managed imprope...

Two simple methods are proposed to respectively impart external force-free reversible shape memory effect to commercial polyolefins: ultrahigh molecular weight polyethylene (UHMWPE) and polypropylene (PP). The key issues lie in the utilization of the partially entangled molecular chains of UHMWPE and the medium crystalline phases of PP as the reversible internal stress providers. The acquired reversible shape memory effect further proves to be applicable for assisting repeatedly self-healing of wider cracks. Compared to the conventional approaches, which used to introduce cross-linkages into the target materials, the present ones only need physical treatment, so that the valuable thermoplasticity of polyolefins is retained. This work can be regarded as an example of the concept "physically converting instead of chemically modifying" for the preparation of functional polymeric materials based on market available plastics.

The present work is focused on developing external stress-free two-way triple shape memory polymers (SMPs). Accordingly, a series of innovative approaches are proposed for the material design and preparation. Polyurethane prepolymers carrying crystalline polytetrahydrofuran (PTMEG) and poly(ε-caprolactone) (PCL) as the switching phases are respectively synthesized in advance and then cross-linked to produce the target material. The stepwise method is believed to be conducive to manipulation of the relative contribution of PCL and PTMEG. Moreover, the chain extender, 2-amino-5-(2-hydroxyethyl)-6-methylpyrimidin-4-ol (UPy), is incorporated to establish hydrogen bonds among the macromolecules. By straightforward stretching treatment at different temperatures, the hydrogen bond networks are successfully converted into an internal stress provider, which overcomes the challenge of stress relaxation of the melted low melting temperature polymer (i.e., PTMEG) and increases the efficiency of stress transfer. Meanwhile, the contraction force of the switching phases is tuned to match the internal tensile stress. As a result, the internal stress provider can closely collaborate with melting/recrystallization of the crystalline domains, leading to the repeated multiple shape memory effects. The cross-linked polyurethane is thus able to reversibly morph among three shapes and displays its potentials as soft robot and actuator. The strategy reported here has the advantages of easily accessible raw materials, simple reaction, and facile programing/deprograming/reprograming, so that it possesses wide applicability.

Co-immobilization of two or more molecules with different and complementary functions to prevent thrombosis, suppress smooth muscle cell (SMC) proliferation, and support endothelial cell (EC) growth is generally considered to be promising for the re-endothelialization on cardiovascular stents. However, integration of molecules with distinct therapeutic effects does not necessarily result in synergistic physiological functions due to the lack of interactions among them, limiting their practical efficacy. Herein, we apply heparin and nitric oxide (NO), two key molecules of the physiological functions of endothelium, to develop an endothelium-mimetic coating. Such coating is achieved by sequential conjugation of heparin and the NO-generating compound selenocystamine (SeCA) on an amine-bearing film of plasma polymerized allylamine. The resulting surface combines the anti-coagulant (anti-FXa) function provided by the heparin and the anti-platelet activity of the catalytically produced NO. It also endows the stents with the ability to simultaneously up-regulate α-smooth muscle actin (α-SMA) expression and to increase cyclic guanylate monophosphate (cGMP) synthesis of SMC, thereby significantly promoting their contractile phenotype and suppressing their proliferation. Importantly, this endothelium-biomimetic coating creates a favorable microenvironment for EC over SMC. These features impressively improve the antithrombogenicity, re-endothelialization and anti-restenosis of vascular stents in vivo.

Surface modification with poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) is an effective method for improving hemocompatibility. Peptide GREDVY immobilized on Ti is of great benefit to endothelialization. Micropattern of PMPC and GREDVY can regulate cells distribution, behaviors, and nitric oxide (NO) release. Copper can be used as catalytic to release NO from a donor in vitro, which can inhibit platelets adhesion, activation, and aggregation. The Ti-PDA(Cu)-M/R(P) micropattern was fabricated with PMMPC-HD {PMMPC [monomer contain MPC and methacrylic acid (MA)] was cross-linked with hexamethylene diamine} and peptide Gly-Arg-Glu-Asp-Val-Tyr (GREDVY) using PDMS stamp, and it was characterized by SEM, FTIR, and XPS. The results demonstrated that the PMPC and peptide GREDVY were immobilized onto polydopamine successfully. Simultaneously, the copper existed in polydopamine was confirmed by XPS. The rate of NO release in vitro catalyzed by copper ions was 1.5–5.3 × 10−10 mol/(cm2 min). It will be beneficial to inhibiting platelets adhesion and proliferation of ECs.

Functional microdomains consisting of multiple molecules have widespread applications. However, most of available methods reported so far have a common limitation for widespread practical use. Herein, we reported a facile method based on material-independent polydopamine surface chemistry to realize the area-selective immobilization of dual amine-/thiol-terminal bioactive molecules assisted by photolithography. We transferred the photoresist pattern to the polydopamine coating surface, and specific molecules were respectively covalently immobilized in the microdomain. The results demonstrated that molecular anchoring is area-selective and quantitatively controllable. Thus, this versatile method provides a new insight into the creation of regionally chemical multicomponent surfaces and could build a potential platform for promising application in sensors, molecular biology, and genetic diagnosis.

Diamond-like carbon (DLC) films were deposited by electron cyclotron resonance plasma-chemical vapor deposition (ECR-CVD) at different substrate bias potential (Us = −200 and −800 V). The mechanical properties and microstructure uniformity of the DLC films deposited at different positions (the distance between substrate and ECR plasma source, Decr-s) were studied. The results showed that the ionization of acetylene (C2H2) at different positions decreased with the increase of Decr-s at substrate bias potential Us = −200 V. The plasma distribution was non-uniform, so the mechanical properties and structure of the DLC films varied a lot with the change of deposition position. At substrate bias potential Us = −800 V, an additional self-sustained discharge around the substrate could be generated during ECR plasma discharge, then the ionization of C2H2 and the plasma distribution uniformity at different positions were found to be improved. The uniformity of mechanical properties and structure of DLC films could be improved due to enhanced ionization of C2H2 in front of the substrate at high values of the negative substrate bias (Us = −800 V).

A series of carbon-coated nickel nanoparticle modified boron-doped diamond (Ni(C)-BDD) composite electrodes with different amounts of carbon coating were fabricated. The effects of heat treatment time on the electrochemical performance of the Ni(C)-BDD electrodes for glucose detection were investigated. The morphology and composition of the composite electrodes were assessed by scanning electron microscopy and Raman spectroscopy. Ni catalyzed the carbon inside boron-doped diamond (BDD) into graphite layer which was coated on the surface of Ni nanoparticles at high temperature. As thermal catalytic treatment time prolonged, the carbon coated on Ni nanoparticles became more and more obvious. Electrochemical results indicate that the Ni(C)-BDD composite electrode shows excellent electrochemical performance for glucose oxidation. Compared to the 5 min-Ni(C)-BDD electrode, the 30 and 60 min-Ni(C)-BDD electrodes need longer heat treatment time, and in return the Ni nanoparticles are covered by more carbon layer, and the current response after one-month measurement is 81.11% and 81.55%, respectively. The 60 min-Ni(C)-BDD electrode has a sensitivity of 1130 and 420 μA·mM−1·cm−2 in the detection range of 1 μM to 4 mM and 4 to 10 mM, respectively, its LOD is 0.69 μM, and the current response after one month's test remains 81.55% of the initial value. The composite electrode has high sensitivity, good selectivity and long-term stability for glucose detection.

A Ni/Cu/boron-doped diamond (Ni/Cu/BDD) complex electrode for non-enzymatic glucose electrochemical detection was prepared by a simple two-step heat treatment method. Scanning electron microscopy (SEM), Raman spectroscopy and electrochemical workstation were used to characterize the surface morphology, composition and electrochemical properties of the electrode, respectively. The results showed that Ni reacted with BDD under high temperature catalytic conditions forming a porous structure, and stabilized Cu on the surface of BDD due to the superior wettability between Cu and Ni. Compared to Ni/BDD and Cu/BDD electrodes, Ni/Cu/BDD electrode exhibited enhanced catalytic activity in glucose detection, such as an extremely wide detection range (0.022–18.3 mM), high sensitivity (1007.688 μAmM−1 cm−2, which was 1.28 times higher than that of the Ni/BDD electrode), great selectivity and excellent long-term stability (93.3% after one month).

Titanium oxide (Ti-O) films with different thicknesses were deposited on 316 L stainless steel and bare metal stents with the filtered cathodic vacuum arc technique. The adhesion of the Ti-O films with different thicknesses on the 316 L stainless steel sheets was studied by the tension test. The adhesion, corrosion resistance, and fatigue behavior of the Ti-O film-modified stents were then evaluated. The results show that a 25-nm-thick Ti-O film on stainless steel is tightly adhered on the stainless steel after 40% relative elongation of the steel substrate. The 25-nm-thick Ti-O film-modified bare metal stent has sufficient mechanical stability, good corrosion resistance, and can withstand 380 million cycles of pulsatile fatigue testing without film destruction and delamination. A clinical trial of the bilayer drug eluting stent (DES) with a titanium oxide base layer and an anti-proliferative sirolimus top layer shows that our DES tends to reduce the incidence of late thrombosis.

Microstructure engineering has aroused tremendous interest to tailor the electrochemical properties of an sp3/sp2-bonded carbon composite in the chemical sensing field. In this work, the undoped di...

Optimal target-sputtering mode for Aluminum Nitride thin film deposition by high power pulse magnetron sputtering (HPPMS)

Clustering for hyperspectral images (HSIs) is a very challenging task because HSIs usually have large spectral variability, high dimensionality, and complex structures. The main issue of this study is to develop an improved sparse subspace clustering (SSC) method for HSIs. As an extension of spectral clustering, SSC algorithm has achieved great success; however, the direct self-representation dictionary which is created by raw samples has poor representation power and also the widely used dictionary learning (DL) such as K-Singular Value Decomposition (K-SVD) faces with the problems of high computational complexity. In this study, the authors propose a novel HSI clustering method based on sparse DL and anchored regression. The proposed method follows three stages: (i) sparse DL; (ii) anchored subspace construction and regression; and (iii) representation-based spectral clustering. Specifically, we adopt a fast sparse DL method under a double sparsity constrained optimising model to capture the intrinsic HSIs. To establish a compact subspace for collaborative representation, we present an anchored subspace construction method by using atoms clustering and grouping methods. Owing to the anchored subspace, we can fast compute the representation coefficients with a predefined projection matrix. Experimental results demonstrate that the proposed method achieves the best performance for the HSIs clustering.

Owing to its high ionization degree, high power pulsed magnetron sputtering (HPPMS) has proven advantageous for Cu film growth. In this study, Cu films with different thicknesses deposited by HPPMS at different peak powers were prepared. Moreover, a titanium (Ti) interlayer was used to improve the Cu (111) out-of-plane preferred orientation and adhesion. The films prepared at high peak power exhibited high tensile stress, large grain size, and low electrical resistivity. Thicker Cu films exhibited lower stress and larger grain size, resulting in better electrical conductivity and adhesion. At the same time, a Ti interlayer with (002) preferred orientation could greatly improve the (111) out-of-plane preferred orientation and adhesion of the Cu film.

Agricultural terraces, as typically artificial landforms, have maintained an important role throughout human history. Terrace ridges, which form the main constructive part of terraces, face the greatest risk from gully or gravity erosion. Mapping terrace ridges can benefit agricultural production management and soil-and-water conservation. This study presents a contour-directional detection method that automatically maps terrace ridges by considering the image features and topographic features of terraces. First, the terrace areas were extracted via object-based image analysis. Second, the Canny edge detector was employed to extract all edges from the image, and a digital elevation model (DEM) was used to generate the contour direction. The contour direction and edge image were then overlaid to implement the contour-directional detection method, which detects ridges along the contour direction. Finally, those candidate terrace ridges which lengths exceed an appropriate threshold were identified as terrace ridges. Five study areas located in the Loess Plateau of China were used to validate the proposed method. The results showed that the correctness, completeness, and quality ranged from 82.57% to 94.92%, from 82.51% to 88.39%, and from 70.28% to 84.40%, respectively. However, the proposed method is widely available and can be easily applied by using open global images and DEMs, such as Google Earth images and ASTER GDEM.

Thrombosis and infections of extracorporeal circuits and indwelling medical devices are the two major life-threatening complications faced in clinical practice. Herein, we report a novel and facile metal–phenolic–amine surface modification strategy to engineer a multifunctional coating on these devices to combat thrombosis and infection. This strategy is inspired by the metal–catecholamine coordination complex of [Fe(dopa)3] in mussels, in which Cu(II) ions (metal), plant polyphenol gallic acid (phenol) and cystamine (amine) are employed to fabricate a copper–phenolic–amine network. Our in vitro and in vivo experiments reveal that the resultant Cu(II)-chelating coatings endow the modified tubing with not only durable antibacterial properties, but also capability to persistently generate anticoagulant therapeutic nitric oxide (NO) gas in the presence of endogenous S-nitrosothiols (RSNO) from fresh blood. We anticipate that our simple and multifunctional coating strategy will be a milestone in the development of surface engineering, especially that of biomedical devices.

Functionalizing cardiovascular biomaterials with an extracellular matrix (ECM) via in vitro decellularization has been applied as an effective method to improve the biocompatibility of implants. However, the current ECM modified materials used for surface engineering implants have functional restrictions compared with the natural blood vessel due to distinguished cell phenotypes in vitro. Herein, we are inspired by the natural vascular basement membrane which is composed of an ECM secreted by physiological endothelial cells (EC) and smooth muscle cells (SMC), preparing a novel ECM coating by successive cell culture and decellularization: appropriately scaled hyaluronic acid (HA) micro-patterns are used to regulate the SMC phenotype to contraction and simulate the blood flow shear stress (BFSS) effect to control the EC physiological phenotype. The nature-inspired ECM coating significantly improves the material's hemocompatibility, cytocompatibility and tissue compatibility, and may be promising to break the function limitation of a single ECM and address more clinical complications.