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Objectives: To test the effect of traditional up-sampling slice thickness (ST) methods on the reproducibility of CT radiomics features of liver tumors and investigate the improvement using a deep neural network (DNN) scheme. Methods: CT images with ≤ 1 mm ST in the public dataset were converted to low resolution (3 mm, 5 mm) CT images. A DNN model was trained for the conversion from 3 mm-ST and 5 mm-ST to 1 mm-ST and compared with conventional interpolation-based methods (cubic, linear, nearest) using structural similarity (SSIM) and peak-signal-to-noise-ratio (PSNR). Radiomics features were extracted from the tumor and tumor ring regions. The reproducibility of features from images converted using DNN and interpolation schemes were assessed using the concordance correlation coefficients (CCC) with the cutoff of 0.85. The paired t-test and Mann-Whitney U test were used to compare the evaluation metrics, where appropriate. Results: CT images of 108 patients were used for training (n=63), validation (n=11) and testing (n=34). The DNN method showed significantly higher PSNR and SSIM values (p < 0.05) than interpolation-based methods. The DNN method also showed a significantly higher CCC value than interpolation-based methods. For features in the tumor region, compared with the cubic interpolation approach, the reproducible features increased from 393 (82%) to 422(88%) for the conversion of 3mm-to-1mm, and from 305(64%) to 353(74%) for the conversion of 5mm-to-1mm. For features in the tumor ring region, the improvement was from 395 (82%) to 431 (90%) and from 290 (60%) to 335 (70%), respectively. Conclusions: The DNN based ST up-sampling approach can improve the reproducibility of CT radiomics features in liver tumors, promoting the standardization of CT radiomics studies in liver cancer.

Previous studies have suggested that the intratumoral texture features may reflect the tumor recurrence risk in intrahepatic cholangiocarcinoma (ICC). The peritumoral features may be associated with the distribution of microsatellites. Therefore, integrating the imaging features based on intratumoral and peritumoral areas may provide more accurate predictions in tumor recurrence (both early and late recurrences) than the predictions conducted based on the intratumoral area only. This retrospective study included 209 ICC patients. We divided the patient population into two sub-groups according to the order of diagnosis time: a training cohort (159 patients) and an independent validation cohort (50 patients). The MR imaging features were quantified based on the intratumoral and peritumoral (3 and 5 mm) areas. The radiomics signatures, clinical factor-based models and combined radiomics-clinical models were developed to predict the tumor recurrence. The prediction performance was measured based on the validation cohort using the area under receiver operating characteristic curve (AUC) index. For the prediction of early recurrence, the combined radiomics-clinical model of intratumoral area with 5 mm peritumoral area showed the highest performance (0.852(95% confidence interval (CI), 0.724–0.937)). The AUC for the clinical factor-based model was 0.805(95%CI, 0.668–0.903). For the prediction of late recurrence, the radiomics signature of intratumoral area with 5 mm peritumoral area had the optimal performance with an AUC of 0.735(95%CI, 0.591–0.850). The clinical factor-based showed inferior performance (0.598(95%CI, 0.450–0.735)). For both early and late recurrences prediction, the optimal models were all constructed using imaging features extracted based on intratumoral and peritumoral areas together. These suggested the importance of involving the intratumoral and peritumoral areas in the radiomics studies.

Multipartite entanglement has been widely employed in quantum information processing. However, the unavoidable noise in quantum channels causes the maximally multipartite entangled state to degrade to the mixed state. In this paper, we propose a highly efficient multipartite entanglement purification protocol (MEPP) for the polarization Greenberger–Horne–Zeilinger state. Unlike conventional MEPPs, where two pairs of polluted entanglement are usually required, our protocol only requires one noisy copy of polarization-time-bin hyperentanglement and exploits the time-bin entanglement to purify the polarization entanglement. This feature increases the efficiency of our MEPP. Our MEPP may have potential applications in long-distance quantum communication.

Strained materials can exhibit drastically modified physical properties in comparison to their fully relaxed analogues. We report on the x-ray absorption spectra (XAS) and magnetic circular dichroism (XMCD) of a strained NiFe2O4 inverse spinel film grown on a symmetry matched single crystal MgGa2O4 substrate. The Ni XAS spectra exhibit a sizable difference in the white line intensity for measurements with the x-ray electric field parallel to the film plane (normal incidence) vs when the electric field is at an angle (off-normal). A considerable difference is also observed in the Fe L 2,3 XMCD spectrum. Modeling of the XAS and XMCD spectra indicate that the modified energy ordering of the cation 3d states in the strained film leads to a preferential filling of 3d states with out-of-plane character. In addition, the results point to the utility of x-ray spectroscopy in identifying orbital populations even with elliptically polarized x-rays.

Two-dimensional (2D) metallic transition metal dichalcogenides (TMDCs) with large specific surface areas and high conductivities are promising catalysts for electrocatalytic hydrogen production. The highly active edges of the 2D metallic TMDCs are the desirable catalytic sites for the hydrogen evolution reaction (HER). Herein, the vanadium diselenide (VSe2) quantum dots with high-density edge sites are prepared by tip sonication of the self-detached VSe2 nanosheets. The spontaneously released VSe2 nanosheets, without chemical-involved transfer, offer a noncontaminated catalyst for HER. Compared to the VSe2 nanosheets, VSe2 quantum dots with a high density of active edges present a significant enhancement of the electrocatalytic performance. The reduced overpotential and transfer resistance indicate the lower Gibbs free energy and faster faradic process of the VSe2 quantum dots for HER. The active edge sites of VSe2 quantum dots show improved catalytic properties in thermodynamic and kinetic aspects. The VSe2 quantum dots loaded on a carbon cloth could be used as a flexible electrode for HER. This work provides an effective way to regulate the defects of the 2D TMDCs for high-performance HER catalysts and also offers a catalyst for flexible HER.

In order to improve the steady-state performance of the traditional model predictive control and reduce the amount of calculation of the control algorithm, this paper proposes a new fast three-vector predictive current control algorithm, which uses the principle of deadbeat control of the dq-axis current to calculate the reference voltage vector, and obtains the reference voltage vector position through sector judgment, combined with the three-vector model predictive control algorithm, the optimal voltage vector is directly applied to the motor, without the need to predict the behavior of the system under the voltage vector, which greatly reduces the amount of calculation. At the same time, due to the introduction of three vectors, three functions are applied in one cycle. The voltage vector greatly improves the steady-state characteristics of the system. The simulation results show that the proposed new three-vector predictive current control algorithm can reduce the amount of calculation and improve the steady-state characteristics of the system.

Non-volatile memory (NVM) devices with non-volatility and low power consumption properties are important in the data storage field. The switching mechanism and packaging reliability issues in NVMs are of great research interest. The switching process in NVM devices accompanied by the evolution of microstructure and composition is fast and subtle. Transmission electron microscopy (TEM) with high spatial resolution and versatile external fields is widely used in analyzing the evolution of morphology, structures and chemical compositions at atomic scale. The various external stimuli, such as thermal, electrical, mechanical, optical and magnetic fields, provide a platform to probe and engineer NVM devices inside TEM in real-time. Such advanced technologies make it possible for an in situ and interactive manipulation of NVM devices without sacrificing the resolution. This technology facilitates the exploration of the intrinsic structure-switching mechanism of NVMs and the reliability issues in the memory package. In this review, the evolution of the functional layers in NVM devices characterized by the advanced in situ TEM technology is introduced, with intermetallic compounds forming and degradation process investigated. The principles and challenges of TEM technology on NVM device study are also discussed.

Subgrade collapse is a frequent geological hazard all over the world, which seriously threatens safety of human life and economic development. Compared with conventional methods of collapse, employing geotextile basal reinforcement with the features of reinforcement and filtration can achieve better treatment. In this paper, four symmetrical semi-section model tests with different width of collapse treated by geotextile and one full-section model test were carried out. Data acquisition instruments and particle image velocimetry (PIV) equipment were applied to research soil pressure, vertical displacement of filling and tensile force of geotextile. The following results were achieved: the results obtained from symmetric semi-section and full-section model test was proximal so that the symmetrical semi-section model test had certain feasibility; the laying of geotextile basal reinforcement had good effect on collapse treatment; the width of collapse area was an crucial factor affecting the collapse treatment using geotextile and the geotextile with high tensile strength and enough buried depth should be employed when dealing with large scale collapse problems.

Subgrade collapse is widespread in karst areas of south China, which is easily causing economic losses and casualties. Compared with the traditional treatment methods, using geotextile has obvious advantages in treating the subgrade after karst collapse. In this paper, two scale model tests with different laying depth of geotextile used to treat karst collapse were performed. Instrumentations and particle image velocimetry system (PIV) were applied to investigate soil pressure, vertical displacement of filling and tension distribution of geotextile. Following results were found: from the point of view of soil pressure, compared with deep buried, there had not enough stable soil under the shallow buried geotextile to improve the collapse treatment effect effectively; Compared with using deep buried geotextile, shallow buried geotextile would cause a larger overall settlement with the surrounding fill, which reduced the reinforced effect and had unsatisfactory treatment effect. Therefore, the geotextile with deep layout should be used in the collapse control and the soil beneath it should be compacted to achieve a good treatment effect.

The axiomatization of physical theories is a fundamental issue of science. The first-order axiomatic system SpecRel for special relativity proposed recently by Andreka et al. is not enough to explain all the main results in the theory, including the twin paradox and energy-mass relation. In this paper, from a four-dimensional space-time perspective, we introduce the concepts of world-line, proper time and four-momentum to our axiomatic system SpecRel+. Then we introduce an axiom of mass (AxMass) and take four-momentum conservation as an axiom (AxCFM) in SpecRel+. It turns out that the twin paradox and energy-mass relation can be derived from SpecRel+ logically. Hence, as an extension of SpecRel, SpecRel+ is a suitable first-order axiomatic system to describe the kinematics and dynamics of special relativity.

Broadband infrared photodetectors based on two-dimensional (2D) materials which are the research focus in the infrared field, have wide applications in remote sensing, thermal imaging, and astronomy observation. In this article, the photodetector based on 2D ferromagnetic material CoSe is studied at room temperature, demonstrating the air-stable, broadband, and up to long wavelength properties. The CoSe material is applied to infrared photodetectors for the first time. The 2D material CoSe is synthesized by using the chemical vapor deposition method. The size of the as-grown CoSe is up to 71.8 μm. The photoresponse of the CoSe photodetector ranges from 450 nm to 10.6 μm. The photoresponsivity of this photodetector is up to 2.58 A W-1 under the 10.6 μm illumination at room temperature. This work provides a new material for broadband photodetector at room temperature and builds a bridge for the magnetoelectronic and broadband photoelectric fields.

Two-dimensional (2D) transition metal dichalcogenides alloys are potential materials in the application of photodetectors over a wide spectral range due to their composition-dependent bandgaps. The study of bandgap engineering is important for the application of 2D materials in devices. Here, we grow the Mo1−x W x Se2 alloys on mica, sapphire and SiO2/Si substrates by chemical vapor deposition (CVD) method. Mo1−x W x Se2 alloys are grown on the mica substrates by CVD method for the first time. Photoluminescence (PL) spectroscopy is used to investigate the effects of substrates and interlayer coupling force on the optical bandgaps of as-grown Mo1−x W x Se2 alloys. We find that the substrates used in this work have an ignorable effect on the optical bandgaps of as-grown Mo1−x W x Se2. The interlayer coupling effect on the optical bandgaps of as-grown Mo1−x W x Se2 is larger than the substrates effect. These findings provide a new way for the future study of the growth and physical properties of 2D alloy materials.

The transition rate of a double well system driven by cross-correlated noises has been investigated, in when the correlation times between the noises are nonzero. From numerical computation, we find followings: (1) The transition rate decreases as the lambda (lambda is the strength of the correlations between noises) increases. (2) The transition rate increases as the tau (tau is the correlation time between noises) increases. It imglies that tau and lambda play opposite roles in the transition rate of the system (3). For the case of perfectly correlated noises (lambda = 1), there is no the suppressed phenomenon in the double well system with cross-correlated noise sources.

A Medium Energy Beam Transport line 1 (MEBT1) has been designed for Injector Scheme II of the China ADS project. To match the beam from RFQ to Superconducting (SC) Half Wave Resonator (HWR) sections with emittance preservation, the MEBT1 has been designed to be mechanically compact. Working at 162.5 MHz, the MEBT1 transports a 10 mA, 2.1 MeV proton beam using seven quadrupoles and two bunching cavities within 2.7 meters. Three collimators are placed between every two adjacent quadrupoles to collimate the beam halo. Design and construction of the MEBT1 are presented in this paper.

CoNiFe patterned films with rectangular elements, all 600-nm wide but of different lengths, were fabricated and investigated by ferromagnetic resonance experiment and micromagnetic simulation. An in-plane magnetic uniaxial anisotropy was exhibited, and its value increases with the increase of the aspect ratio of the elements, which was fitted by the model, including a quasi-ellipsoid demagnetizing field and a non-uniform demagnetizing field. The relative importance of the non-uniform demagnetizing field decreased from 0.26 to 0.16 with the increase of the length—width aspect ratio of the patterned element from 1.5 to 10. The demagnetizing factors in the three principal axes were determined from the experimental data of ferromagnetic resonance, which agreed reasonably well with the values calculated by micromagnetic simulation. The calculation also indicated that the interaction between elements could be neglected when the edge-to-edge spacing between neighboring elements was larger than 3 μm in our patterned films.

The instability characteristics of hydrogenated amorphous silicon (a-Si:H) thin film transistors (TFTs) with various interfacial and bulk defect states were systematically investigated. It was found that, under positive bias stresses, the threshold voltage shifts of a-Si:H TFT's with the same interfacial defect states but with different bulk defect states exhibited similar threshold voltage shift characteristics. In contrast, a-Si:H TFT's with different interfacial defect states but the same bulk defect states showed threshold voltage shifts proportional to the interfacial defect states under positive bias stresses. Furthermore, both the above kinds of a-Si:H TFT under positive bias stresses exhibited that the subthreshold swing shift characteristics closely related to both the interfacial and bulk defect states.