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Conventional methods for measuring viscosity rely on macroscopic device components, which are difficult to miniaturize. The magnetic nano‐stirbars are small enough to enter tiny spaces and can spin without precise installation, making them an ideal candidate for exploring new methods. It is shown that a dense layer of Au nanowires can be grown on the silica surface of the nano‐stirbars, as a means to modulate the viscous resistance during their spinning and to make them visible under an optical microscope. The uniform growth of Au nanowires and the slight fluctuation of the spinning rates are investigated. It is shown that the nano‐stirbars with the hairy layer of Au nanowires can be used to measure the viscosity in microscopic liquid systems, such as microfluidic chambers and capillary tubes, involving cell media and blood samples. It is believed that the success with the proof‐of‐concept tests will open a window for further miniaturization of the nano‐stirbars for measuring in ultrasmall systems. [ABSTRACT FROM AUTHOR]

Vitamin D deficiency is widespread in different populations and regions worldwide and has become a global health issue. The vitamin D status of the population in the Yunnan Province of Southwest China has not been evaluated to date. Therefore, in this study, we evaluated the vitamin D status according to the serum concentrations of 25‐hydroxyvitamin D (25(OH)D) in individuals of Yunnan Province, a low‐latitude, high‐altitude and multiracial region in China. The data on 25(OH)D concentrations from October 2012 to December 2017 were retrospectively collected and assessed using the laboratory information system from 52 950 hospital‐based participants (age, 1 day–96 years; females, 73.74%). The serum concentration of 25(OH)D was evaluated using a chemiluminescent immunoassay. The analysis was stratified by sex, age, sampling season, testing year, minority, residential district, latitude, altitude and meteorological factors. Vitamin D status was classified as follows: severe deficiency: <10 ng/mL; deficiency: <20 ng/mL; insufficiency: <30 ng/mL; and sufficiency: ≥30 ng/mL. The results showed that vitamin D deficiency is highly prevalent in Yunnan Province in a hospital‐based cohort, with a deficiency and severe deficiency rate of 65.1% and a sufficiency rate of 5.30%. Significantly lower vitamin D levels and sufficiency rates were observed in females than in males (20.13 ± 7.22 ng/mL vs. 17.56 ± 6.66 ng/mL and 8.20% vs. 4.20%; p < 0.01, respectively); in spring and winter (16.93 ± 6.24 ng/mL; 2.97% and 16.38 ± 6.43 ng/mL; 3.06%, respectively) than in summer and autumn (20.23 ± 7.14 ng/mL; 8.02% and 19.10 ± 6.97 ng/mL; 6.61% [p < 0.01], respectively); and in older individuals (0–6 years: 28.29 ± 13.13 ng/mL vs. >60 years: 14.88 ± 8.39 ng/mL; p < 0.01). Relatively higher vitamin D levels were observed in individuals of Yi, Zhuang, Hani, Dai, Miao and Lisu minorities and lower levels in individuals of Hui and Zang minorities compared with those of the Han nationality (p < 0.01). The mean sunlight duration, mean air temperature, maximum ultraviolet value and latitude were significantly correlated with vitamin D levels (r = −0.53, 0.60, 0.31, −0.68, respectively; p < 0.05). These results suggest that vitamin D status is influenced by sex, age, minority, latitude and some meteorological factors in areas with high and low altitudes. Hence, new public health policies, such as advice on sunshine exposure, food fortification and nutrition education, as well as the implementation of vitamin D supplementation programmes must be considered to alleviate vitamin D deficiency in Yunnan province, Southwest China. [ABSTRACT FROM AUTHOR]

It is a great challenge to study the mechanical property of nanomaterials because it is difficult to get a hold of them and apply force. A convenient alternative method via electrospun fibers is shown, where silica‐coated fivefold twinned silver nanowires are well aligned in the fiber and the fibers are aligned in the membrane to a similar direction of macroscopic stretching. The product silver nanowires show necks whereas the fractured silica shell acts as the internal marker for the extent of stretching. Surprisingly, the stretched neck length depends on the nanowire diameter but is independent of the degree of stretching, indicating that the necks have arrived at a limiting intermediate state, which is otherwise hard to achieve for nanomaterials. The necks are studied by transmission electron aberration‐corrected microscopy and steered molecular dynamics simulation, revealing that the build‐up of dislocations and stacking faults (the Lomer–Cottrell (LC) locks) are responsible for trapping the necks at similar limiting states. [ABSTRACT FROM AUTHOR]

We developed a novel method using a combined light‐registration/light‐projection system along with an off‐the‐shelf, instant‐assembly modular jig construct that could help surgeons improve bone resection accuracy during sarcoma surgery without many of the associated drawbacks of 3D printed custom jigs or computer navigation. In the novel method, the surgeon uses a light projection system to precisely align the assembled modular jig construct on the bone. In a distal femur resection model, 36 sawbones were evenly divided into 3 groups: manual‐resection (MR), conventional 3D‐printed custom jig resection (3DCJ), and the novel projector/modular jig (PMJ) resection. In addition to sawbones, a single cadaver experiment was also conducted to confirm feasibility of the PMJ method in a realistic operative setting. The PMJ method improved resection accuracy when compared to MR and 3DCJ, respectively: 0.98 mm versus 7.48 mm (p < 0.001) and 3.72 mm (p < 0.001) in mean corner position error; 1.66 mm versus 9.70 mm (p < 0.001) and 4.32 mm (p = 0.060) in mean maximum deviation error; 0.79°–4.78° (p < 0.001) and 1.26° (p > 0.999) in mean depth angle error. The PMJ method reduced the mean front angle error from 1.72° to 1.07° (p = 0.507) when compared to MR but was slightly worse compared to 0.61° (p = 0.013) in 3DCJ. The PMJ method never showed an error greater than 3 mm, while the maximum error of other two control groups were almost 14 mm. Similar accuracy was found with the PMJ method on the cadaver. A novel method using a light projector with modular jigs can achieve high levels of bone resection accuracy, but without many of the associated drawbacks of 3D printed jigs or computer navigation technology. [ABSTRACT FROM AUTHOR]

Accurate bone registration is critical for computer navigation and robotic surgery. Existing registration systems are expensive, cumbersome, limited in accuracy and/or require intraoperative radiation. We recently reported a novel method of registration utilizing an inexpensive, compact, and X‐ray‐free structured‐light 3D scanner. However, this technique is not always practical in a real surgical setting where soft tissue and blood can obstruct the continuous line‐of‐sight required for structured‐light technology. We sought to remedy these limitations using a novel technique using rapid‐setting impression molding to capture bone surface features and scan the undersurface of the mold with a structured‐light scanner. The photonegative of this mold is compared to the preoperative computed tomography (CT)‐scan to register the bone. A registration accuracy study was conducted on 36 CT‐scanned femur sawbones, simulating typical exposure in hip/knee arthroplasty and bone tumor surgery. A cadaver experiment was also conducted to evaluate the feasibility of using the impression molding in a more realistic operating room setting. The registration accuracy of the proposed technique was 0.50 ± 0.19 mm. This was close to the reported accuracy of 0.43 ± 0.18 mm using a structured‐light scanner without impression molding (p = 0.085). In comparison, historical values for "paired‐point" and intraoperative CT image‐based registration methods currently used in modern robotic/computer‐navigation systems were 0.68 ± 0.14 mm (p = 0.004) and 0.86 ± 0.38 mm, respectively. The registration accuracy of the cadaver experiment was consistent with that of sawbone experiments. Although future studies are needed to extend to human subjects, this study shows that the impression molding method can produce comparable or better registration accuracy than the existing techniques. [ABSTRACT FROM AUTHOR]

The synthesis of multi‐carbon products through electrochemical CO2 reduction reactions has attracted great interest from researchers. Herein, nitrogen‐ and carbon‐doped copper nanocatalyst (NC−Cu) containing abundant Cu−N−C active sites was prepared by thermal decomposition of the complexes containing copper and melamine. The NC−Cu catalyst exhibited an ideal current density of 22 mA cm−2 at −0.93 V versus reversible hydrogen electrode (vs. RHE) in CO2‐saturated 0.5 M KHCO3 medium, with ethanol as the predominant product at −0.93 V (vs. RHE) and a maximum Faraday efficiency of 31 %. The current density of the catalyst remained almost unchanged after 20 h of electrolysis, indicating its excellent stability. The excellent catalytic ability is attributed to the abundant Cu−N−C active sites of NC−Cu with 3D porous microstructure. [ABSTRACT FROM AUTHOR]

Sand erosion is a major factor that shortens the service life of aircraft in desert regions. The anti‐erosion performance of titanium alloys may be improved using TiN coatings. However, few studies have employed Ti sputtering on Ti transition layers to improve the erosion resistance of the coatings. Herein, TiN coatings with a sputtering layer between the Ti transition layer and the TiN layer were deposited on a Ti–6Al–4V alloy by filtered cathodic vacuum arc deposition. For comparison, another group of TiN coatings without a Ti sputtering layer but processed using the same deposition parameters were prepared. The effects of the nanoscale sputtering layer on the microstructure, mechanical properties, and anti‐erosion performance of the coatings were investigated using scanning electron microscopy, transmission electron microscopy, X‐ray diffraction, and nanoindentation. The results show that the introduction of a Ti sputtering layer promoted the growth of TiN grains, leading to the formation of finer and denser TiN columnar grains. The preferred orientation of the coatings with the sputtering layer is (111) plane, whereas that of the coatings without the sputtering layer is (200) plane. The TiN coatings containing a sputtering layer exhibit higher hardness, elastic modulus, and H3/E2 ratio, which enhances the anti‐erosion performance of the coatings. The coatings with a sputtering layer exhibited better erosion resistance (erosion rate reduced by 75%) than the coatings without a sputtering layer. The underlying mechanism to understand the effect of the sputtering layer on the erosion resistance was discussed based on variations in the microstructure and mechanical properties of the coatings with and without the Ti sputtering layer. Ti sputtering layer was finally proved to be an effective method to improve the erosion resistance of TiN coatings. [ABSTRACT FROM AUTHOR]

Atomic structure, adhesion energy, and electronic properties of the bonding nature at CrN(200)/Ni(111) interfacial region are studied by first‐principle calculations based on density functional theory (DFT). A new method for building the heterostructure of CrN(200)/Ni(111) is proposed to solve the large lattice mismatching between CrN(200) and Ni(111) slab. Three models (OT, ST, and TL) with different interface distance are built up, and the total energy for each of them is calculated. Comparing with other stacking sequence, TL sites with 1.9‐Å spacing at the interfacial region shows the biggest value of adhesion energy after geometry relaxation. Furthermore, the contour of charge density, partial charge density of states, and Bader charge values of the TL sites with 1.9‐Å spacing are plotted out and calculated. Results indicate that covalency bonding between Ni and N ions and metallic bonding between Ni and Cr atoms are formed at the interfacial region. [ABSTRACT FROM AUTHOR]

This paper proposes a novel LSTM model for precise prediction of initial register value in OLED Gamma tuning. Usually the bottleneck of Gamma tuning speed depends on the accuracy of initial register value prediction in IC modules for each bind point. By utilizing the long short‐term memory character of LSTM, high prediction accuracy is achieved which greatly shrink the search time for register value, thus reducing the overall average tuning time for each bind point of OLED screens and enhancing the amounts of adjusted screens per unit time in autonomous pipelines. [ABSTRACT FROM AUTHOR]

Graphene based copper‐nickel bimetal nanocomposite (Cu3Ni2‐rGO) was prepared via a one‐step solvothermal procedure, in which Ni(OH)2 and Cu(OH)2 were used as precursors. Structural characterization confirms that the as‐prepared Cu3Ni2‐rGO nanocomposite is composed of Cu3Ni2 nanoparticles in the size range of 20–100 nm and the reduced graphene oxide (rGO) sheets. Benefiting from the combination of Cu3Ni2 and rGO, the Cu3Ni2‐rGO nanocomposite exhibits excellent catalytic performance on reducing highly toxic Cr(VI) at room temperature. The reduction of Cr(VI) (40 mL, 100 mg L−1) can be completed within 6 min using Cu3Ni2‐rGO nanocomposite as the catalyst, which is much more efficient than using monometallic nanocomposite containing only Cu or Ni. Moreover, Cu3Ni2‐rGO nanocomposite can be magnetically separated, which enables effective recycle. Besides, Cu3Ni2‐rGO shows good cycling stability. [ABSTRACT FROM AUTHOR]

As a typical cyber physical system (CPS), a smart grid should facilitate more robust integration and interoperability of information models and subsystems so that the performance of the physical system can be optimized. However, the intrinsic complexity and heterogeneity of CPS are two of the biggest obstacles to interoperation and interconnection among various information models and subsystems. In order to address the dilemma, this paper proposed a systematic, data‐centric system design approach comprehensively including data‐oriented system architecture, data resources abstraction and data‐driven mechanisms. To be specific, the autonomous decentralized system (ADS) theory is introduced to establish the data‐centric system architecture. A MQTT/MQTT‐SN‐based communication protocol, which supports not only IP‐based devices but also non‐IP devices, is proposed to meet the requirement of publish–subscribe mechanism of the ADS‐based system architecture. A data‐centric meta‐interface is proposed to formalize the data resources abstraction. A Lebesgue sampling‐based data exchange mechanism, which is proven tractable but effective, is proposed to realize the data‐driven mechanism. As user energy management system (UEMS) is an integral part of smart grid, a realistic UEMS for heating project is considered a typical case to study the performance of the proposed data‐centric system. This paper is one of the first few papers that systematically propose a systematic data‐centric system design approach for a smart grid, which is supported by aspects of system architecture, communication protocol and data exchange mechanism. © 2019 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]

Abstract: CuCr2O4/reduced graphene oxide (rGO) composites were prepared using a two‐step method. Detailed characterizations of the material were performed with X‐ray diffraction (XRD), Zeta potential, Fourier transform infrared (FT‐IR), transmission electron microscopy (TEM), X‐ray photoelectron spectroscopy (XPS), Raman spectra, and Thermal Gravimetric Analyzer (TGA). The characterizations showed that the ∼50 nm CuCr2O4 nanoparticles were successfully supported on the rGO via static electricity. The TGA results showed that the quality of rGO in composites was around 10%. The experimental results showed that the catalysts obtained high catalytic activity for the selective oxidation of cyclohexane to cyclohexanone with H2O2. The catalyst obtained a conversion rate of cyclohexane of up to 95.8%. 78.1% cyclohexanone selectivity was obtained. The catalyst had good cycling stability after 5 reuses. Compared to the other composite materials, the catalyst had high catalytic activity for the selective oxidation of cyclohexane to cyclohexanone. [ABSTRACT FROM AUTHOR]

This study deals with guaranteed state estimation of power systems in the bounded‐error context, which avoids the effect of inexact matching of the assumed statistical hypotheses on the error. A new approach, based on interval constraint propagation, is proposed to compute guaranteed estimates of state variables and measurements. According to the feature of power systems, two improvements based on interval constraint propagation are presented to improve contraction and obtain narrow interval images. First, a monotonicity‐based contractor is exploited because of the monotonicity of measure function to part of state variables. Second, the constraints set are extended by combining the measurement constraints. The improved method is guaranteed, contraction efficient and time efficient. The results, achieved using the proposed method, are compared with those typical existing methods to demonstrate its effectiveness. Tests are carried out on the IEEE 14‐bus system and the IEEE 118‐bus system, respectively. [ABSTRACT FROM AUTHOR]

Determining subduction‐related processes is crucial for understanding lithological heterogeneity, as substantial quantities of slabs are recycled into the mantle. Molybdenum isotopes are valuable for distinguishing sources materials due to the significant isotope differences between the crust and the mantle. In this study, we systematically investigate Mo isotopes in a suite of well‐characterized continental basalts from Keluo and Halaha‐Chaoer, located in Northeast China. The δ98Mo values of Keluo range from −0.41 to −0.23‰, with an average of −0.34‰, while Halaha‐Chaoer samples ranged from −0.18 to −0.12‰, with an average of −0.15‰. The δ98Mo values of Keluo basalts are lighter than the mean value of fresh oceanic basalts (−0.21‰), whereas those of Halaha‐Chaoer basalts are similar to oceanic basalts. Combined with other geochemical indications (LOI, Ce/Pb, La/Yb and so on), the Mo isotopic variations cannot be attributed to chemical weathering, continental crust contamination or magmatic processes. Instead, the δ98Mo variations in this study are explained by the incorporation of different oceanic crustal materials into the magma sources. Correlations of δ98Mo with Ba/Th, Th/U, 143Nd/144Nd indicated that both sediment and altered oceanic crust have significantly influenced these variations. This study demonstrates the potential of Mo isotopes to distinguish different types of recycled oceanic crust materials. [ABSTRACT FROM AUTHOR]

A magnetic heterogeneous α‐Fe2O3/CdS‐RGO (RGO: reduced graphene oxide) composite photocatalyst was synthesized using the one‐step hydrothermal method. The α‐Fe2O3 and CdS nanoparticles with a diameter range of 20~60 nm were synchronously loaded/distributed on the surface of RGO. The as‐synthesized α‐Fe2O3/CdS‐RGO nanocomposites were analyzed using X‐ray diffraction, Fourier transform‐infrared spectra, BET surface area, scanning electron microscopy, transmission electron microscopy, UV–Vis diffusive reflectance spectra and Raman spectroscopy. Compared with the pure CdS, α‐Fe2O3 and α‐Fe2O3/CdS nanoparticles, the α‐Fe2O3/CdS‐RGO nanocomposites expanded the adsorption range of visible‐light, and showed significant photocatalytic performance and cyclic stability for degradation of methylene blue in visible light. Also, the remarkable catalytic performances mainly depend on its special structure of the α‐Fe2O3/CdS‐RGO, which enabled the effective separation of the electron–hole pairs. These attractive features make the α‐Fe2O3/CdS‐RGO nanocomposite to be a photocatalyst with great application potential in water pollutants treatment. [ABSTRACT FROM AUTHOR]