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Full-waveform inversion is an important and widely used method to reconstruct subsurface velocity images. Waveform inversion is a typical nonlinear and ill-posed inverse problem. Existing physics-driven computational methods for solving waveform inversion suffer from the cycle-skipping and local-minima issues, and do not mention that solving waveform inversion is computationally expensive. In recent years, data-driven methods become a promising way to solve the waveform-inversion problem. However, most deep-learning frameworks suffer from the generalization and overfitting issue. In this article, we developed a real-time data-driven technique and we call it VelocityGAN, to reconstruct accurately the subsurface velocities. Our VelocityGAN is built on a generative adversarial network (GAN) and trained end to end to learn a mapping function from the raw seismic waveform data to the velocity image. Different from other encoder–decoder-based data-driven seismic waveform-inversion approaches, our VelocityGAN learns regularization from data and further imposes the regularization to the generator so that inversion accuracy is improved. We further develop a transfer-learning strategy based on VelocityGAN to alleviate the generalization issue. A series of experiments is conducted on the synthetic seismic reflection data to evaluate the effectiveness, efficiency, and generalization of VelocityGAN. We not only compare it with the existing physics-driven approaches and data-driven frameworks but also conduct several transfer-learning experiments. The experimental results show that VelocityGAN achieves the state-of-the-art performance among the baselines and can improve the generalization results to some extent. [ABSTRACT FROM AUTHOR]

Abstract Space debris laser ranging with a 4.2 W double-pulse 532 nm picosecond laser at a pulse repetition frequency of 1 kHz was achieved at the Shanghai satellite laser ranging (SLR) station, which receiving telescope was 60 cm. Space debris' radar cross sections were from 2 m2 to 12 m2, and ranging precision was up to centimeters. A compound regenerative amplifier was used to realize double pulses output with pulse space of 4.1 ns. Double pulses would have the same detection ability as the equal energy single pulse. A 500 μm diameter avalanche photo-diode detector with less than 10 kHz dark noise and a quantum efficiency of 40% at 532 nm was developed to improve the measurement capability. And also a spectral filter with high efficiency and narrow bandwidth were applied. Basing on the Shanghai SLR system, the laser ranging to space debris with picosecond laser at 1 kHz was successfully implemented for the first time among the global SLR stations. The results showed that the ranging precision root-mean-square can be achieved about 5 cm. It will be very useful to monitor and study the space debris. [ABSTRACT FROM AUTHOR]

A numerical multiscale model is used to resolve the high computation complexity in the ac loss calculation of large-scale superconducting devices and proves advantageous with regard to time and memory requirements. In the multiscale model, the background field estimation method is of crucial importance to the calculation accuracy. In this paper, we propose four new background field estimation methods, including the Jacobi Gauss–Seidel hybrid and iteration methods, to improve the accuracy and expand the application scope of the multiscale model. A high temperature superconducting solenoid magnet is used to test the performance of these four methods and the results are compared with those of the H-formulation reference model and the multiscale model with a J0 uniform background field estimation method. Results show that in the 19 A/50 Hz ac transport current test case: the Jacobi Gauss– hybrid and iteration methods reduce the error of the ac loss mean value/peak value to 7.88%/5.89%, 5.71%/2.4%, 3.22%/1.22%, and 1.83%/0.69% with the total time cost reduced by 15.7, 8.9, 13.5, and 7.8 times. The multiscale model is expected to achieve even higher accuracy in applications where the ac loss is relatively small due to its coincidence property. The greatly improved accuracy makes the multiscale model a reliable substitute for the H-formulation model. In addition, the idea of iteration and back substitution in background field correction widely expands the application scope of the multiscale model. Alternative background field estimation methods allow the multiscale model to be applied flexibly according to the requirement of the calculation speed and accuracy. The feature of small degrees of freedom resolves the high computation complexity of the ac loss calculation model and reduces the memory requirement. All these merits make the multiscale model competitive in the calculation of ac loss. [ABSTRACT FROM AUTHOR]

The calculation of ac loss is an essential part in the thermal stability estimation of the high-temperature superconductor (HTS) superconducting magnetic energy storage system (SMES). In this paper, we propose an artificial neural network (ANN) prediction model to calculate the ac loss in real-time and apply the ANN prediction model to a 150 kJ self-made HTS SMES. The ANN prediction model is composed of a multi-scale model and an ANN. An ac loss data set calculated with the multi-scale model is used to train the ANN, and a validation data set is used to test the accuracy of the ANN after training. By comparing with the homogenization model, we find that the multi-scale model is reliable when used for ac loss calculation and suitable for building ac loss data set due to its high calculation speed. The ANN prediction model is verified to be reliable for fast estimation of the ac loss, and its accuracy improves as the scale of the training data set increases. [ABSTRACT FROM AUTHOR]

An average power of 3 W green picosecond laser at a pulse repetition frequency of 1 kHz was reported. At the Shanghai satellite laser ranging (SLR) station, many satellites were measured with this laser and a narrow spectrum filter in the daytime. Satellites of the Beidou satellite navigation system for the Chinese, Global navigation satellite system for the Russian and Galileo satellite navigation system for the Europe were measured respectively. Especially ranging precision root mean square was up to 19.4 mm for the satellite of compassi5 about 37,000 km far from the earth. A Nd:YVO 4 mode-locked laser with an etalon, a dual-length of Nd:YAG regenerative amplification cavity, single-pass two Nd:YAG modules amplifier and nonlinear optical materials LiB 3 O 5 frequency doubling were designed. An average power of 3 W in 532 nm was obtained with pulse width of 30 ps, and angle of divergence was 0.8 mrad. Using the dual-length of regenerative cavity would greatly decrease the laser's volume and improve stability of picosecond laser. A narrow spectrum filter can reduce a lot of optics noise from the sun, and so all the satellites were almost be measured with this laser in the daytime at the Shanghai SLR station. [ABSTRACT FROM AUTHOR]

Primary alkylamines are generally used as ligands for the synthesis of colloidal II–VI group quantum dots (QDs). However, knowledge of the effects of these ligands on the nanocrystalline structure in the literature is scarce and often contradictory. Herein, the structural evolution of CdSe QDs synthesized with primary alkylamines of different chain lengths and concentrations and at various reaction temperatures has been investigated. Absorption spectroscopy, XRD, HRTEM and Fourier transform imaging were applied to characterize the structure of the CdSe QDs. The results demonstrate that CdSe QDs preferentially form the wurtzite structure with shorter-chain and higher-concentration primary alkylamines at higher reaction temperatures. In contrast, the zinc blende structure is formed in the presence of longer-chain and lower-concentration primary alkylamines at lower reaction temperatures. By precisely controlling the experimental conditions, CdSe QDs with a pure zinc blende phase have been successfully achieved. [ABSTRACT FROM AUTHOR]

To obtain size distribution of nanoparticles, scanning electron microscope (SEM) and transmission electron microscopy (TEM) have been widely adopted, but manual measurement of statistical size distributions from the SEM or TEM images is time-consuming and labor-intensive. Therefore, automatic detection methods are desirable. This paper proposes an automatic image processing algorithm which is mainly based on local adaptive Canny edge detection and modified circular Hough transform. The proposed algorithm can utilize the local thresholds to detect particles from the images with different degrees of complexity. Compared with the results produced by applying global thresholds, our algorithm performs much better. The robustness and reliability of this method have been verified by comparing its results with manual measurement, and an excellent agreement has been found. The proposed method can accurately recognize the particles with high efficiency. [ABSTRACT FROM AUTHOR]

Inthis work, a general strategy was proposed for fine manipulatingintrinsic growth of water-soluble salts belonging to different crystalsystems. Various hollow microsphere hierarchical architectures assembledwith hopperlike single crystal blocks of cubic KBr, orthorhombic (NH4)2SO4, or hexagonal Na2SO3have been designed and prepared via microemulsions. Intrinsicgrowth manipulations of different water-soluble salts has been successfullyachieved by preventing growth of the outside surface of each singlecrystal block via a diffusion-limit effect of the interfaces betweenthe oil phase and aqueous droplets. As a result, hopperlike singlecrystals of water-soluble salts belonging to different crystal systemswere formed. Furthermore, octahedral NaCl hopperlike single crystal,rather than their typical cubic shape, has also been fabricated bymanipulating their growth rates along different lattice directionsin combination with urea as additives. The large amount of fine manipulationof intrinsic growth of water-soluble salts will provide us with adeep understanding of crystallography of inorganic salts, as wellas facilitate design and production of water-soluble salts architectureswith corresponding shapes, according to the different requirements. [ABSTRACT FROM AUTHOR]

Abstract: Diffusion tensor imaging (DTI) may provide an accurate noninvasive method of detecting degenerative matrix alterations in human lumbar intervertebral discs (IVDs). This study aimed to investigate age-related degenerative changes in human lumbar IVDs using DTI. Thirty asymptomatic volunteers ranging in age from 25 to 67 years underwent single-shot diffusion weighted echo-planar imaging on a 3 T scanner. DTI-derived metrics including fractional anisotropy (FA) and mean diffusivity (MD) were analyzed by a histogram analysis method. A Mann–Whitney test was used to compare subject groups (young and elderly) with respect to the diffusion measures, and piecewise linear regression was used to characterize the change in each metric as a function of age. We found significant age-related changes in the elderly adult group, with decrease of MD (11%, P<.001) and increase of FA (20%, P<.001). Our results demonstrate that the degenerative-related changes taking place in the IVDs through aging can be quantitatively accessed by DTI-derived metrics, while the morphologic changes are difficult to be identified in conventional T2-weighted images. Our initial findings suggest that it would be worthwhile to validate the relationship between DTI metrics and the actual degenerative status of IVDs using extracted disc samples and to extend it to studies on patients with degenerative discs in order to further explore the clinical usefulness and relevance of DTI. [Copyright &y& Elsevier]

This paper reports the finding of an investigation of a surface molecular self-assembly strategy for molecular imprinting of polymer nanowires/nanotubes. It has been demonstrated that 2,4,6-trinitrotoluene (TNT) templates were spontaneously assembled onto aminopropyl group-modified alumina pore walls by a strong charge-transfer complexing interaction between amino groups and electron-deficient nitroaromatics, forming a novel basis of surface molecular imprinting. While an additional amount of TNT templates was further replenished into a precursor mixture, a stepwise progressive polymerization was designed toward the controllable preparation of TNT-imprinted polymer nanowire/nanotube arrays in an alumina membrane. The imprinted nanowires/nanotubes with a high density of surface-imprinted sites and regular interior sites exhibit the high capacity of binding TNT molecules, which is nearly 2.5-3.0-fold that of normal imprinted particles. Moreover, the imprinted nanotubes and nanowires have ~6- and 4-fold increase in the rate of binding TNT molecules, respectively. The combination of surface molecular assembly with nanostructures in the imprinting technique can create more effective recognition sites than the only use of porogens in traditional approaches. This novel, facile strategy reported herein can be further expected to fabricate various molecular recognition nanoarrays for sensing or analytic applications. [ABSTRACT FROM AUTHOR]

In this paper, we report a simple polypeptide-directed strategy for fabricating large spherical assembly of CaCO3 nanoparticles. Stepwise growth and assembly of a large number of nanoparticles have been observed, from the formation of an amorphous liquidlike CaCO3-polypeptide precursor, to the crystallization and stabilization of polypeptide-capped nanoparticles, and eventually, the spherical assembly of nanoparticles. The "soft" poly(aspartate)-capping layer binding on a nanoparticle surface resulted in the unusual soft nature of nanoparticle assembly, providing a reservoir of primary nanoparticles with a moderate mobility, which is the basis of a new strategy for reconstructing nanoparticle assembly into complex nanoparticle architectures. Moreover, the findings of the secondary assembly of nanoparticle microspheres and the morphology transformation of nanoparticle assembly demonstrate a flexible and controllable pathway for manipulating the shapes and structures of nanoparticle assembly. In addition, the combination of the polypeptide with a double hydrophilic block copolymer (DHBC) allows it to possibly further control the shape and complexity of the nanoparticle assembly. A clear perspective is shown here that more complex nanoparticle materials could be created by using "soft" biological proteins or peptides as a mediating template at the organic−inorganic interface. [ABSTRACT FROM AUTHOR]

A separate two-step process with a rapid nucleation and a subsequent template-directed growth has been employed to synthesize uniform Ag nanoparticles, which avoids a classical un-refrained ripening process resulting in a wide size distribution. Some silver nanocrystallites prepared by this approach are particularly interesting because of their unusual nanostructures with multiple nanostripes caused by stacking faults. [Copyright &y& Elsevier]

Intracellular viscosity plays an important role in regulating cellular morphology and physiology and is closely related to a host of diseases. Especially, the changes in mitochondrial viscosity will cause some common diseases such as hyperlipidemia, Alzheimer's disease and cancer. In this work, we report the design of a red-emissive molecular rotor for the detection of mitochondrial viscosity in live cells. The probe showed fascinating performance, such as specific targeting to mitochondria, high sensitivity to viscosity, and rapid fluorescence response, especially the dual response mode of fluorescence intensity and fluorescence lifetime. By using this probe, we realized monitoring of the mitochondrial viscosity variations in live cells under different physiological processes. Our study offers an opportunity to discover potential tools for mitochondria-related physiology and pathology investigation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Rapid SERS analysis and screening of clinical cell samples. • Electroporation can introduce nanoprobes into cells in a short duration. • Noninvasive screening of nasopharyngeal cancer based on SERS detection of exfoliated cells. Nasopharyngeal carcinoma (NPC) is a malignant tumor in head and neck. Early diagnosis can effectively improve the survival rate of patients. Nasopharyngeal exfoliative cytology, as a convenient and noninvasive auxiliary diagnostic method, is suitable for the population screening of NPC, but its diagnostic sensitivity is low. In this study, an electroporation-based SERS technique was proposed to detect and screen the clinical nasopharyngeal exfoliated cell samples. Firstly, nasopharyngeal swabs was used to collected the nasopharyngeal exfoliated cell samples from NPC patients (n = 54) and healthy volunteers (n = 60). Then, gold nanoparticles, as the Raman scattering enhancing substrates, were rapidly introduced into cells by electroporation technique for surface-enhanced Raman scattering (SERS) detection. Finally, SERS spectra combined with principal component analysis (PCA) and linear discriminant analysis (LDA) were employed to diagnose and distinguish NPC cell samples. Raman peak assignments combined with spectral differences reflected the biochemical changes associated with NPC, including nucleic acid, amino acid and carbohydrates. Based on the PCA-LDA approach, the sensitivity, specificity and accuracy of 98.15 %, 96.67 % and 97.37 %, respectively, were achieved for screening NPC. This study offers valuable assistance for noninvasive NPC auxiliary diagnosis, and has grate potential in expanding the application of the SERS technique in clinical cell sample testing. [ABSTRACT FROM AUTHOR]

High-precision Time-Frequency Rack (HTFR) mission, a part of experiment module II of the China Space Station (CSS), was equipped with a Sr optical clock, H-maser, and laser-cooled microwave clock. To compare time and frequency across widely separated clocks, a microwave link, and a pulsed laser link were both established, which probably enables new possibilities for fundamental science, geodesy, and metrology. Based on the existing relativistic theory for time and frequency transfer, we derive a relativistic model of satellite-ground laser time transfer on CSS (CLT), which can be of direct use in CLT data processing. In addition to first and second-order Sagnac effects, it also includes relativistic rate shifts, atmospheric refraction, and turbulence, laser retroreflector array (LRA) range correction, and position correction between detector and reflector, satisfying the stability evaluation of CSS atomic clocks with fractional frequency stability of 3 × 10−17/10000 s. Additionally, we numerically investigate the link error magnitude and use Monte Carlo simulations to assess the impact of correcting for link errors on the stability of the CLT, taking into account the CSS orbit and attitude determinations as well as the CLT payload calibration parameters. It is shown that the CLT link can be considered to reach a TDEV of approximately 0.1 ps/300 s while meeting the CSS design objectives. The primary factors that influence the stability of the CLT are the position correction between detector and reflector, LRA range correction, and the coupling relation of these two error distributions. [ABSTRACT FROM AUTHOR]

The mission of Chinese Space station is underway in China and the different type of clock systems will be carried and high stability and accuracy of time transfer is demanded. Laser Time Transfer (LTT) will be implemented between ground and Space Station and the LTT payload is being developed by Shanghai Astronomical Observatory (SHAO) with the time comparison single shot precision of 60ps, stability of less than 1ps @ 300s, and 1ps @ 1day. This paper will introduce the progress of LTT payload, including the design of the detector and timer, the optical design, testing results of the system stability and the future developments of this project. [ABSTRACT FROM AUTHOR]

Metal–organic framework (MOF) supported nanocatalysts are attracting great attentions in heterogeneous catalysis. However, they are still less explored and poorly understood in catalyzing solid–gas reactions. In current work, two MOF supported Pt nanocatalysts were prepared by immersion method coupled with the most commonly used NaBH4 (Pt/UiO-66-NaBH4) and H2 (Pt/UiO-66-H2) reduction, and their catalytic CO oxidation performances were investigated. NaBH4 and H2 reduction both provide highly dispersed Pt/UiO-66 nanocatalysts, and the two prepared catalysts display excellent CO oxidation activities. Moreover, CO oxidation durability tests reveal that Pt/UiO-66-NaBH4 shows superior durability and structure stability, which are much better than those of Pt/UiO-66-H2. The high structure stability of Pt/UiO-66-NaBH4 also endows it with good H2O and CO2 tolerance. This work attempts to elucidate the influence of reduction methods on the structures and catalytic CO oxidation performances of Pt/UiO-66 catalysts by employing XRD, TEM, N2-sorption, XPS and in situ DRIFTS techniques. Furthermore, the mechanism of CO oxidation was studied by in situ DRIFTS, and the result reveals that the CO oxidation on the two catalysts follows different mechanism. [ABSTRACT FROM AUTHOR]

The losses of Superconducting Magnetic Energy Storage (SMES) magnet are not neglectable during the power exchange process with the grid. In order to prevent the thermal runaway of a SMES magnet, quantitative analysis of its thermal status is inevitable. In this paper, the loss characteristics of a self-developed 150 kJ SMES magnet are analyzed by means of experiments and simulations, including the loss of the joint resistance, the eddy current loss of the metal cooling structures and the AC loss of the superconducting magnet. A thermal model of the magnet was built to theoretically analyze the relationship between the current and magnet temperature variation. Three kinds of power compensation experiments were carried out to study the thermal characteristics of the SMES magnet. The temperature variation of the magnet under these three operating conditions was simulated. The simulation results and experimental results are compared and analyzed. [ABSTRACT FROM AUTHOR]

As a specific biological marker for the occurrence and progression of tumor cells, detection of telomerase activity is of great importance for the physiological research of tumors. However, in situ measurement of telomerase activity in living cells still remains a challenge. Herein, we report a precisely designed oligonucleotide-functionalized gold nanoparticle probe that has realized high-efficiency detection of telomerase activity for cellular imaging toward the identification of tumors. Our method has achieved intracellular imaging of telomerase activity and shows good performance towards the distinction of tumor cells from normal ones. Moreover, the method reported here for tracking tumor cells in blood has wide applications in cancer diagnosis. This strategy offers an opportunity for cancer diagnosis, guiding therapy and evaluating prognosis. [ABSTRACT FROM AUTHOR]

A green route is designed to gain a clear idea of growth mechanism of complex VO2 (B) hierarchical microstructures, since this kind of metal oxide has various metastable phases due to their diverse valence states. Three-dimensional (3D) uniform flower-like VO2 (B) hierarchical microstructure has thus been assembled with the interleaving nanoplates, which are about 25 nm in thickness and well-crystallized in structure with {114} planes as the dominant surfaces. Results of the systemic control experiments revealed that formation of the flower-like VO2 (B) results from a fast nucleation-growth process, where ethylene glycol (EG) not only acts as a green solvent and reductive agent, but also plays a key role in self-assembly of the resulted VO2 (B) hierarchical microstructures. Hydroxyl amount on the solvent molecule is crucial in formation and shape control of VO2 (B) hierarchical microstructures. Result of this work would be helpful to understand the growth mechanism of complex three-dimensional hierarchical superstructures of different metal oxides, which is very important to material science and inorganic synthetic chemistry. [ABSTRACT FROM AUTHOR]

An ideal adsorbent material that combines the multiple capabilities of sensitive detection, efficient adsorption, and repeatable removal of uranium (U) from the environment remains a serious challenge. Herin, a general method was developed for synthesizing a series of phosphate anions (such as: PO 4 3-, P 2 O 7 4-, P 3 O 10 5- and P 6 O 18 6-) modified magnetic mesoporous silica nanoparticles (Fe 3 O 4 @mSiO 2 -Zn2+ NPs). The mesoporous surfaces and abundant phosphate groups provide potential, powerful uranium-binding sites for capturing U(VI) ions. Especially, the optimum adsorption capacity of Fe 3 O 4 @mSiO 2 -Zn2+/P 3 O 10 5- NPs was as high as 885.90 mg·g−1 (298 K), which was higher than that of unmodified or other phosphate anions-modified Fe 3 O 4 @mSiO 2 -Zn2+ NPs. Meanwhile, P 3 O 10 5--binding sites and mesoporous surfaces also strongly restrict U(VI) ions' fluorescence vibrational inactivation, the adsorption results in rapid green fluorescence enhancement (within 180 s), and an ultra-low detection limit (4.5 nmol·L–1), which is well below the standard in drinking water of the World Health Organization (WHO). Furthermore, even after 5 cycles, the adsorbent still maintained their original adsorption capacity of 80.21% and displayed excellent selectivity for detecting and removing U(VI) from seawater. Based on these results, the Fe 3 O 4 @mSiO 2 -Zn2+/P 3 O 10 5- NPs seem to be a suitable multifunctional adsorbent for the detection, adsorption, and removal of U(VI) from environment. [Display omitted] • General method for synthesizing phosphate anion-modified Fe 3 O 4 @mSiO 2 -Zn2+ NPs. • Surface modification significantly enhances U(VI) sorption capacity. • Visible green fluorescence enhancement facilitates U(VI) ions detection. • Excellent reusability for the repeated separation of U(VI) ions. [ABSTRACT FROM AUTHOR]

Stimuli‐responsive photonic crystals (PCs) have been extensively studied due to their potential in fabrication of anti‐counterfeiting devices and information storage. In this work, using Ca2+ ionic crosslinker, a cholesteric liquid crystalline network (CLCN) based PC able to simultaneously present visible and fluorescence pattern by moisture treatment is designed and prepared. The circularly polarized light from helical structure of CLCN makes the reflected pattern distinguishable under different circular polarizer, implying the unique advantage of this novel coating as anti‐counterfeiting devices. More importantly, due to the thermochromic property of the liquid crystal monomers, permanent pattern is achievable by chemically crosslinking specific region at different temperature. By integrating chemically crosslinking and physically ionic crosslinking, a permanent pattern and a dynamic humidity responsive pattern can be incorporated in a single device, indicating the great potential of this novel photonic coating in information storage. [ABSTRACT FROM AUTHOR]

Abstract: A novel dansyl-based fluorescent probe was synthesized and characterized. It exhibits high selectivity and sensitivity towards Fe3+ ion. This fluorescent probe is photostable, water soluble and pH insensitive. The limit of detection is found to be 0.62μM. These properties make it a good fluorescent probe for Fe3+ ion detection in both chemical and biological systems. Spike recovery test confirms its practical application in tap water samples. [Copyright &y& Elsevier]

Ordered nanoporous nickel (Ni) films were fabricated by a full-replicated process. Replicated from an alumina membrane, the replicated Ni film has a very high aspect ratio of about 360, an ordered nanopore array structure, and a narrow size distribution of the pore diameters. Due to the peculiar fabrication processes, the replicated Ni film is polycrystalline with clear ferromagnetic behavior, which is totally different from that of conventional electroless deposited Ni films. The replicated Ni film does not possess obvious magnetic anisotropy, which is also different from a typical ferromagnetic thin film. [Copyright &y& Elsevier]

A ratiometric fluorescent probe with a large emission shift was developed for the accurate measurement of hydrogen peroxide (H2O2) in sophisticated pyroptosis signaling pathways. The results reported here demonstrate that H2O2, as a principal member of ROS, is a critical upstream signaling molecule in regulating pyroptosis. [ABSTRACT FROM AUTHOR]

The effects of Al–Mg wire replacing Al–Cu wire on the microstructure, microhardness and tensile properties of 2219 aluminum alloy tungsten inert gas (TIG)-welded joints were studied. Comparing joints with Al–Cu wire, the capping welds of joints with Al–Mg wire can be strengthened by the introduction of Mg-containing strengthening phase and the hardness can be significantly improved. However, for joints with Al–Mg wire, both the solidification cracks caused by inappropriate control of alloying element content and the continuous brittle phases at grain boundaries around the weld zone (WZ) can result in the reduced tensile properties. The crack-free weld can be obtained by adjusting the alloying system of WZ. Furthermore, the geometry of WZ also affected the tensile properties of joints with Al–Mg wire. [ABSTRACT FROM AUTHOR]

Osteoarthritis (OA), characterized by the degeneration of articular cartilage, is a major problem in aging populations, and cartilage chondrocytes have been indicated to serve a curial role in the progression of OA. MicroRNA-200b-3p (miR-200b) was preliminarily identified to participate in OA. However, its role and mechanism of action in injured chondrocytes in OA remain unclear to date. In the present study, lipopolysaccharide (LPS)-treated cells isolated from normal knee articular cartilage were used to mimic inflammatory injury of OA chondrocytes. Cell viability, apoptosis and inflammatory responses were detected using Cell Counting Kit-8, flow cytometry and enzyme-linked immunosorbent assay, respectively. The expression levels of miR-200b and fucosyltransferase-4 (FUT4) were measured by reverse transcription-quantitative PCR and western blotting. The association between miR-200b and FUT4 was verified using TargetScan software, dual-luciferase reporter assay and RNA immunoprecipitation. The results indicated that LPS treatment decreased cell viability of primary chondrocytes, and increased apoptosis rate and production of IL-1β, IL-6 and TNF-α. The expression level of miR-200b was downregulated, and that of FUT4 was upregulated in OA cartilage tissues and LPS-treated normal chondrocytes compared with normal cartilage tissues and chondrocytes. Overexpression of miR-200b via transfection with miR-200b mimic inhibited the apoptosis rate and reduced the levels of IL-1β, IL-6 and TNF-α in LPS-stimulated chondrocytes. However, the suppressive effect of miR-200b overexpression on the LPS-induced inflammatory injury in chondrocytes was reversed by the restoration of FUT4 levels. Notably, FUT4 was indicated to be a downstream target of miR-200b and was negatively regulated by miR-200b. Taken together, the results of the current study indicated that miR-200b protected chondrocytes from LPS-induced inflammatory injury in vitro by targeting FUT4. These findings revealed the miR-200b/FUT4 axis as a potential candidate to target the degeneration of cartilages, thereby inhibiting the progression of OA. [ABSTRACT FROM AUTHOR]

Imitating the structures and behaviors of natural creatures is of great significance to scientists to explore novel materials for practical applications. However, the design and fabrication of biomimetic devices with complex and outstanding performances is still on the way. A bilayer film composed of liquid crystalline networks (LCN) film and hydrochromic aggregation‐induced‐emission molecule‐doped hydrophilic layer is prepared. Under different relative humidity, the composite film can deform and change fluorescence color simultaneously. The influence of the content of the hydrophilic matrix on the fluorescent property and humidity‐responsive behaviors of the bilayer film is investigated. Thanks to the mechanical anisotropy provided by uniform‐aligned LCN film, different modes of deformation of the bilayer film are achievable, like bending, curling, and twisting. More importantly, due to the independence of the LCN film and the non‐mesogenic molecules brought by this bimorph strategy, complex alignment of the LCN film and modification by immiscible molecules are realized in a single LCN actuator. Based on the functional composite film, artificial flowers showing synergistic blooming and shape‐changing is prepared. By regulating the molecular alignment of the LC mesogens of the LCN film, the artificial flowers can imitate various blooming behaviors of natural flowers like confederate jasmine and jade lotus. [ABSTRACT FROM AUTHOR]

The discovery of color-controlled fiber holds profound importance for the development of flexible wearable devices and soft display equipment. In this study, a kind of electrically triggered chameleon fiber (ETF) was fabricated. Liquid metal was used as the conductive core structure, and red, blue and yellow thermochromic pigments were mixed into a polyacrylonitrile solution with dimethyl sulfoxide as solvent to form the thermochromic matrix shell structure. By coaxial wet spinning, reversible, ETF with a core-shell structure was prepared. We utilized joule heating to drive the thermochromic pigments change the conjugate plating by adjusting the color. ETF has therefore ideal electrochromism properties. This smart fiber appearing as a dark purple fiber at room temperature and can change color when the current is adjusted. The color expressive of ETFs changed from dark purple (0.2 A) to green (0.6 A), then to yellow (1 A), and finally to white (1.2 A). When the current was turned off, the fibers were able to return to their original color due to the conjugated structure transformation of the three thermochromic pigments. Moreover, ETFs demonstrated good thermal stability, tolerating temperatures of up to 200 ℃. This work offers a simple and cost-effective method for developing soft display equipment. • In this study, a core-shell composite fiber was fabricated. We utilized Joule Heating to drive the thermochromic pigments change the conjugate plating by adjusting the color. Liquid metal was used as the conductive core structure, and thermochromic polyacrylonitrile form the thermochromic matrix structure. • Joule Heating promoted the variation of three thermochromic pigments with temperature rising. Electrically triggered chameleon fibers (ETFs) therefore show successively a remarkable change from dark purple to green to yellow and white. • The strongest properties of fiber are flexibility and editability. These advantages can expand application scenarios of ETF. Inspiring from the digital display, a multiplexed passive display is fabricated via ETFs by adjusting the circuit configuration. [ABSTRACT FROM AUTHOR]

Methylation of the O6-methylguanine methyltransferase (MGMT) gene promoter is correlated with the effectiveness of the current standard of care in glioblastoma patients. In this study, a deep learning pipeline is designed for automatic prediction of MGMT status in 87 glioblastoma patients with contrast-enhanced T1W images and 66 with fluid-attenuated inversion recovery(FLAIR) images. The end-to-end pipeline completes both tumor segmentation and status classification. The better tumor segmentation performance comes from FLAIR images (Dice score, 0.897 ± 0.007) compared to contrast-enhanced T1WI (Dice score, 0.828 ± 0.108), and the better status prediction is also from the FLAIR images (accuracy, 0.827 ± 0.056 ; recall, 0.852 ± 0.080 ; precision, 0.821 ± 0.022 ; and F 1 score, 0.836 ± 0.072). This proposed pipeline not only saves the time in tumor annotation and avoids interrater variability in glioma segmentation but also achieves good prediction of MGMT methylation status. It would help find molecular biomarkers from routine medical images and further facilitate treatment planning. [ABSTRACT FROM AUTHOR]

Understanding the biomolecular interactions in a specific organelle has been a long‐standing challenge because it requires super‐resolution imaging to resolve the spatial locations and dynamic interactions of multiple biomacromolecules. Two key difficulties are the scarcity of suitable probes for super‐resolution nanoscopy and the complications that arise from the use of multiple probes. Herein, we report a quinolinium derivative probe that is selectively enriched in mitochondria and switches on in three different fluorescence modes in response to hydrogen peroxide (H2O2), proteins, and nucleic acids, enabling the visualization of mitochondrial nucleoprotein dynamics. STED nanoscopy reveals that the proteins localize at mitochondrial cristae and largely fuse with nucleic acids to form nucleoproteins, whereas increasing H2O2 level leads to disassociation of nucleic acid–protein complexes. [ABSTRACT FROM AUTHOR]

Understanding the biomolecular interactions in a specific organelle has been a long‐standing challenge because it requires super‐resolution imaging to resolve the spatial locations and dynamic interactions of multiple biomacromolecules. Two key difficulties are the scarcity of suitable probes for super‐resolution nanoscopy and the complications that arise from the use of multiple probes. Herein, we report a quinolinium derivative probe that is selectively enriched in mitochondria and switches on in three different fluorescence modes in response to hydrogen peroxide (H2O2), proteins, and nucleic acids, enabling the visualization of mitochondrial nucleoprotein dynamics. STED nanoscopy reveals that the proteins localize at mitochondrial cristae and largely fuse with nucleic acids to form nucleoproteins, whereas increasing H2O2 level leads to disassociation of nucleic acid–protein complexes. [ABSTRACT FROM AUTHOR]

The cadmium sulfide (CdS) semiconductor nanofibrils have been prepared by a convenient ultraviolet irradiation method at room temperature. Cadmium Sulphate was used as the metal ion sources. Sodium thiosulfate was used as the sulfur source. Hydroxyethyl cellulose (HEC) can act as not only the capping materials but also soft templates in the solution. It was found that not only the concentrations of Cd2+ ions and S2O32− ions but also irradiation time play important roles in the shape-controlled synthesis of the CdS nanomaterials in the solution containing 1% HEC. X-ray diffractometer was used to characterize the products, and transmission electron microscopy (TEM) to determine their morphologhy, and X-ray energy dispersion spectroscopy to determine their chemical composition. [Copyright &y& Elsevier]

Design and fabrication of photomechanical soft actuators has attracted intense scientific interest because of their potential in the manufacture of untethered intelligent soft robots and advanced functional devices. Trifunctional and monofunctional polymerizable molecular motors are judiciously designed and synthesized. Novel light‐driven liquid crystalline networks (LCN) are prepared by crosslinking overcrowded‐alkene‐based molecular motors with different degrees of freedom into the anisotropic LCN. The photoisomerization and thermal helix inversion of light‐driven molecular motors are reversible when only the upper part of the molecular motor is linked to the network, endowing the LCN film with remarkable photoactive performance. However, photochemical geometric change of the light‐driven molecular motor does not work after crosslinking both the upper and lower part of the motor by polymer chains. Interestingly, it is found that the fastened motor can transfer the light energy into localized heat instead of performing photoisomerization. The light‐driven molecular‐motor‐based LCN soft actuators are demonstrated to function as a grasping hand, where the continuous motions of grasping, moving, lifting, and releasing an object are successfully achieved. This work may provide inspiration to the preparation of next‐generation photoactive advanced functional materials toward their wide applications in the areas of photonics, optoelectronics, soft robotics, and beyond. [ABSTRACT FROM AUTHOR]

This study sought to monitor the dynamic process of lymph node (LN) metastasis with intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI), and to investigate the impact of disease course on the detection of metastatic LNs by IVIM-DWI. Twenty female New Zealand rabbits with 2.5–3.0 kg body weight were studied. VX2 cells and egg yolk emulsion were randomly inoculated into one thigh to induce metastatic and inflammatory popliteal LNs, respectively. Eight rabbits underwent IVIM-DWI (14 b values, 0–2000 s/mm2) 2 h prior to, and 14, 21, and 28 days after inoculation (D0, D14, D21, D28). The apparent diffusion coefficient (ADC), true diffusion coefficient (D), pseudodiffusion coefficient (D*), and perfusion fraction (f) were measured and compared between the metastatic and the inflammatory groups at each time point. Three rabbits randomly chosen from the remaining twelve rabbits were sacrificed at each time point to perform hematoxylin and eosin staining and histologic evaluation. The patterns of dynamic change of D*, ADC, and D were different between the metastatic and the inflammatory LNs. The metastatic group had a lower D* value at D14 (p =.003), and greater ADC and D values at both D21 (p =.001, p =.001) and D28 (p =.021, p =.001), compared to the inflammatory group. The f value of the metastatic group was greater than that of the inflammatory only at D28 (p =.001). IVIM-DWI can reflect the dynamic process of LN metastasis, and disease course has a significant influence on the ability of IVIM-DWI to detect metastatic nodes. [ABSTRACT FROM AUTHOR]

The development of powerful and general methods to acquire ubiquitin (Ub) chains has prompted the deciphering of Ub‐mediated processes. Herein, the cysteine‐aminoethylation assisted chemical ubiquitination (CAACU) strategy is extended and improved to enable the efficient semi‐synthesis of atypical Ub chain analogues and Ub‐based probes. Combining the Cys aminoethylation and the auxiliary‐mediated protein ligation, several linkage‐ and length‐defined atypical Ub chains including di‐Ubs, K27C‐linked tri‐Ub, K11/K48C‐branched tri‐Ub, and even the SUMOlated Ub are successfully prepared from recombinantly expressed starting materials at about a 9–20 mg L−1 expression level. In addition, the utility of this strategy is demonstrated with the synthesis of a novel non‐hydrolyzable di‐Ub PA probe, which may provide a new useful tool for the mechanistic studies of deubiquitinase (DUB) recognition. [ABSTRACT FROM AUTHOR]

Purpose: To determine the diagnostic performance of intravoxel incoherent motion (IVIM) parameters to predict tumor recurrence after hepatectomy in patients with hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC).Materials and Methods: One hundred and fifty-seven patients (mean age 52.54 ± 11.32 years, 87% male) with surgically and pathologically confirmed HCC were included. Regions of interests were drawn including the tumors by two independent radiologists. ADC and IVIM-derived parameters (true diffusion coefficient [D]; pseudodiffusion coefficient [D*]; pseudodiffusion fraction [f]) were obtained preoperatively. The Cox proportional hazards model was used to analyze the predictors associated with tumor recurrence after hepatectomy.Results: Forty-seven of 157 (29.9%) patients experienced tumor recurrence. The multivariate Cox proportional hazards model revealed that a D value < 0.985 × 10-3 mm2/s (hazard ratio (HR), 0.190; p = 0.023) was a risk factor for tumor recurrence. Additional risk factors included younger age (HR, 0.328; p = 0.034) and higher serum alpha-fetoprotein (AFP) level (HR, 2.079; p = 0.013). Further, receiver operating characteristic (ROC) analysis showed that the area under the curve (AUC) of the obtained Cox regression model improved from 0.68 for the combination of AFP and age alone to 0.724 for the combination of D value, AFP, and age.Conclusion: The D value derived from the IVIM model is a potential biomarker for the preoperative prediction of recurrence after hepatectomy in patients with HCC. When combined with age and AFP levels, D can improve the predictive performance for tumor recurrence.Key Points: • The recurrence rate of HCC after hepatectomy was higher in patients with ADC, D, and f values that were lower than the optimal cutoff values. • The optimal cutoff values of ADC, D, D*, and f for predicting recurrence in HBV associated HCC were 0.858 × 10-3 mm2/s, 0.985 × 10-3 mm2/s, 12.5 × 10-3 mm2/s, and 23.4%, respectively. • The D value derived from IVIM diffusion-weighted imaging may be a useful biomarker for preoperative prediction of recurrence after hepatectomy in patients with HCC. When combined with age and AFP levels, D can improve the predictive performance for tumor recurrence. [ABSTRACT FROM AUTHOR]

A convenient serum pretreatment method based on coffee ring effect was combined with surface-enhanced Raman spectroscopy to diagnose knee osteoarthritis (KOA) and evaluate the therapeutic effect of icariin. Partial least square (PLS) and support vector machine (SVM) algorithms were employed to establish the discriminant model, and the diagnostic sensitivity, specificity and accuracy of 100%, 98.33% and 98.89%, respectively, were achieved for screening KOA. [Display omitted] • Auxiliary diagnosis and efficacy evaluation in knee osteoarthritis based on SERS. • Robust and repeatable SERS signal based on the coffee ring effect. • Icariin treatment alleviated the pathological changes of knee osteoarthritis. Knee osteoarthritis (KOA), a progressive joint disease, is a leading source of chronic pain and disability, and its diagnosis mainly depends on medical imaging findings and clinical symptoms. This study aimed to explore an auxiliary diagnostic technology and clinical efficacy evaluation in KOA based on surface-enhanced Raman scattering (SERS). Three sequential experiments were performed: 1) preliminary observation of the therapeutic effects of icariin (ICA); 2) using serum SERS spectra obtained from rat models belonging to sham group, KOA group and icariin treatment group, respectively, to analyze the KOA-related expression profiles; 3) employing partial least squares (PLS) and support vector machines (SVM) algorithms to establish KOA diagnosis model. Pathological changes verified the efficacy of icariin in KOA. Raman peak assignment combined with spectral difference analysis reflected the biochemical changes associated with KOA, including amino acid, carbohydrates and collagen. ICA intervention significantly reversed these changes, although full recovery could not be achieved. Based on PLS-SVM approach, the sensitivity, specificity and accuracy of 100%, 98.33% and 98.89%, respectively, were obtained for screening KOA. This work proves that SERS has great potential to be used as an auxiliary diagnostic technology for KOA, and is also helpful for the exploration of novel KOA treatment agent. [ABSTRACT FROM AUTHOR]

BeiDou navigation satellite System (BDS), was the dedicated Chinese Global Navigation Satellite Systems (GNSS). The satellites in the BDS constellation can be tracked by many Satellite Laser Range (SLR) stations, making use of the onboard Laser Retro-reflector Array (LRA). Additionally, some of BDS satellites were also equipped with Laser Time Transfer (LTT) payloads. The measuring data from these instruments provided highly accurate estimations of satellites orbit, and time comparison between satellites and ground clocks.The performance of the BDS LRA and LTT payloads designed by Shanghai Astronomical Observatory (SHAO) were presented, as well as the SLR systems with a one meter-aperture telescope, which provided the ranging precision of centimeter levels for daylight ranging to BDS satellites at the synchronous orbit. For the first time, high precise LTT measurements at the synchronous orbit satellites were performed by the SHAO. The LTT data processing and analysis were presented with the time stability of 20ps at 500s, and a relative frequency stability of 10E-14.The further developments and improvements of Chinese LTT technology were also discussed. Global SLR tracking of BDS satellites were performed by the International Laser Ranging Service, providing accurate range data with global coverage. By using laser data, the accuracy of BDS satellite orbit and broadcast ephemeris were evaluated and the orbit error of BDS satellites was achieved at the meter level. [ABSTRACT FROM AUTHOR]

E3 ligases play a critical role in ubiquitin (Ub) conjugation cascades, and any aberration in their activity is associated with a number of diseases. Advancement in our knowledge of understanding the roles of HECT E3s requires biochemical tools such as activity-based probes (ABPs). In this study we developed a novel dehydroalanine (Dha)-based E2-Ub ABP using a strategy that is a combination of practical hydrazide-based native chemical ligation and sequential Dha formation. The probe could be used for labeling HECT E3s not only in vitro but also in endogenous cellular contexts. Our easy-to-implement method is expected to be useful for the preparation of Dha based Ub family E2 conjugate ABPs. [ABSTRACT FROM AUTHOR]

The dynamics of DNA and RNA structures in live cells are important for understanding cell behaviors, such as transcription activity, protein expression, cell apoptosis, and hereditary disease, but are challenging to monitor in live organisms in real time. The difficulty is largely due to the lack of photostable imaging probes that can distinguish between DNA and RNA, and more importantly, are capable of crossing multiple membrane barriers ranging from the cell/organelle to the tissue/organ level. We report the discovery of a cationic carbon quantum dot (cQD) probe that emits spectrally distinguishable fluorescence upon binding with double‐stranded DNA and single‐stranded RNA in live cells, thereby enabling real‐time monitoring of DNA and RNA localization and motion. A surprising finding is that the probe can penetrate through various types of biological barriers in vitro and in vivo. Combined with standard and super‐resolution microscopy, photostable cQDs allow time‐lapse imaging of chromatin and nucleoli during cell division and Caenorhabditis elegans (C. elegans) growth. [ABSTRACT FROM AUTHOR]

The dynamics of DNA and RNA structures in live cells are important for understanding cell behaviors, such as transcription activity, protein expression, cell apoptosis, and hereditary disease, but are challenging to monitor in live organisms in real time. The difficulty is largely due to the lack of photostable imaging probes that can distinguish between DNA and RNA, and more importantly, are capable of crossing multiple membrane barriers ranging from the cell/organelle to the tissue/organ level. We report the discovery of a cationic carbon quantum dot (cQD) probe that emits spectrally distinguishable fluorescence upon binding with double‐stranded DNA and single‐stranded RNA in live cells, thereby enabling real‐time monitoring of DNA and RNA localization and motion. A surprising finding is that the probe can penetrate through various types of biological barriers in vitro and in vivo. Combined with standard and super‐resolution microscopy, photostable cQDs allow time‐lapse imaging of chromatin and nucleoli during cell division and Caenorhabditis elegans (C. elegans) growth. [ABSTRACT FROM AUTHOR]

Abstract The strength and plasticity of 2219 aluminium alloy tungsten inert gas (TIG)-welded joints are inconsistent, which can compromise the safety of products. Both numerical simulation and experimental methods are used to study why the mechanical properties show a significant variation among 2219 aluminium alloy TIG-welded joints; the reasons can be summarized as involving geometric factors and metallurgical factors. Changes in the front weld width, the penetration depth of the capping weld, and other geometric parameters can have different effects on joints' mechanical properties. Three types of metallurgical factors can negatively affect joints' mechanical properties: i) unfavourable eutectic structure (the presence of coarsened eutectic particles and a thickened grain boundary eutectic structure in the crack initiation region of C10S+C10S welded joints; and the appearance of a continuously elongated eutectic structure close to the fusion line near the crack initiation region of C10S+CYS-welded joints); ii) significant segregation in the weld zone (WZ); and iii) decreased microhardness values in the partially melted zone (PMZ) and in the WZ. Two methods can be adopted to improve the joints' mechanical properties: i) The shapes of the welded joints can be optimized by adjusting the welding process parameters. One example is decreasing the penetration depth of the capping weld by decreasing the welding current and gas flow rate during the second pass. ii) The degree of segregation in the WZ and PMZ can be reduced by properly adjusting the welding heat input and wire feeding speed. Highlights • Geometric and metallurgical factors caused the inconsistency in joint's mechanical properties. • The method of combining numerical simulation and experimental was proposed. • The larger the front weld width, the better the joint's tensile properties. • The shallower the capping weld depth, the better the joint's tensile properties. • Severe segregation caused the unfavourable eutectic structure. [ABSTRACT FROM AUTHOR]

Abstract In recent years, copper nanoclusters (Cu NCs) have attracted a great deal of research interests, because the fluorescence intensity will be significantly enhanced after they aggregate, which makes them an ideal material for constructing chemical sensors. The current Cu NCs based sensor researches focus mainly on the control of surface modification and aggregation conditions. Herein, we report a method for direct detection of Cu2+ ions through in situ cluster formation and aggregation. Glutathione was used as both reducing agent and stabilizing agent, while tetrahydrofuran as the poor solvent. When the analyte of Cu2+ ions were added to the mixed solution, they were reduced and aggregated to generate bright orange emission. The method is easy to operate and the reaction complete within 2 min. The detection limit for Cu2+ ions is as low as 0.17 μM. Based on these findings, we successfully achieved the determination of copper content in naturally occurring mineral. Therefore, the method reported here provides a convenient and sensitive way to perform qualitative analysis of Cu2+ ions. Highlights • A rapid and sensitive method for Cu2+ ions detection was developed. • The method was based on the formation and aggregation of Cu nanoclusters. • Glutathione was used as both reducing agent and stabilizing agent, while tetrahydrofuran as the poor solvent. • Proposed method has been successfully applied in naturally occurring mineral. [ABSTRACT FROM AUTHOR]

Enzyme activity in live cells is dynamically regulated by small‐molecule transmitters for maintaining normal physiological functions. A few probes have been devised to measure intracellular enzyme activities by fluorescent imaging, but the study of the regulation of enzyme activity via gasotransmitters in situ remains a long‐standing challenge. Herein, we report a three‐channel imaging correlation by a single dual‐reactive fluorescent probe to measure the dependence of phosphatase activity on the H2S level in cells. The two sites of the probe reactive to H2S and phosphatase individually produce blue and green fluorescent responses, respectively, and resonance energy transfer can be triggered by their coexistence. Fluorescent analysis based on the three‐channel imaging correlation shows that cells have an ideal level of H2S to promote phosphatase activity up to its maximum. Significantly, a slight deviation from this H2S level leads to a sharp decrease of phosphatase activity. The discovery further strengthens our understanding of the importance of H2S in cellular signaling and in various human diseases. Two for one: A dual‐reactive molecular probe has been devised to simultaneously measure intracellular H2S levels and phosphatase activity. Fluorescent analysis by three‐channel imaging correlation reveals that a slight deviation from the normal H2S level leads to a sharp decrease of phosphatase activity. [ABSTRACT FROM AUTHOR]

Enzyme activity in live cells is dynamically regulated by small‐molecule transmitters for maintaining normal physiological functions. A few probes have been devised to measure intracellular enzyme activities by fluorescent imaging, but the study of the regulation of enzyme activity via gasotransmitters in situ remains a long‐standing challenge. Herein, we report a three‐channel imaging correlation by a single dual‐reactive fluorescent probe to measure the dependence of phosphatase activity on the H2S level in cells. The two sites of the probe reactive to H2S and phosphatase individually produce blue and green fluorescent responses, respectively, and resonance energy transfer can be triggered by their coexistence. Fluorescent analysis based on the three‐channel imaging correlation shows that cells have an ideal level of H2S to promote phosphatase activity up to its maximum. Significantly, a slight deviation from this H2S level leads to a sharp decrease of phosphatase activity. The discovery further strengthens our understanding of the importance of H2S in cellular signaling and in various human diseases. [ABSTRACT FROM AUTHOR]

Telomerase is repressed stringently in normal cells but highly activated in tumours to maintain their uncontrollable growth. We report a ratiometric fluorescence strategy for visualising telomerase activity for tumour identification. Using our strategy, tumour cells and tissues can be differentiated from normal cells and tissues by the naked eye. [ABSTRACT FROM AUTHOR]

Superconducting fault current limiters (SFCLs) are considered as one of the most promising technologies to limit fault current levels, as they can suppress fault currents without adding impedance to the circuit during normal operation. In this paper, a flux-coupling-type SFCL (FC-SFCL) based on disconnecting coupling windings for current reduction is considered as a potential scheme to limit fault currents due to its low steady impedance before a fault and higher current-limiting impedance after a fault. Three types of winding methods of the FC-SFCL are introduced and the main parameters are discussed, along with the voltage distribution of the coils. Based on these, the optimal winding structure is determined, a small-scale test prototype is designed and fabricated, and a series of experimental tests is conducted. From the demonstrated experimental results, the FC-SFCL prototype is able to effectively suppress the fault current’s steady value to a lower level, and it has good performance in terms of current reduction. [ABSTRACT FROM AUTHOR]