Electronically Induced Ferromagnetic Transitions in Sm5Ge4-Type Magnetoresponsive Phases

The correlation between magnetic and structural transitions in Gd5SixGe4−x hampers the studies of valence electron concentration (VEC) effects on magnetism. Such studies require decoupling of the VEC-driven changes in the magnetic behavior and crystal structure. The designed compounds, Gd5GaSb3 and Gd5GaBi3, adopt the same Sm5Ge4-type structure as Gd5Ge4 while the VEC increases from 31  e−/formula in Gd5Ge4 to 33  e−/formula in Gd5GaPn3 (Pn: pnictide atoms). As a result, the antiferromagnetic ground state in Gd5Ge4 is tuned into the ferromagnetic one in Gd5GaPn3. First-principles calculations reveal that the nature of interslab magnetic interactions is changed by introducing extra p electrons into the conduction band, forming a ferromagnetic bridge between the adjacent [∝2Gd5T4] slabs

The Unified Supplementary Damping Method Based on Voltage-Soured Converter High-Voltage Direct Current Transmission Through Robust Control

The VSC-HVDC system can damp the inter-area low-frequency oscillation effectively. To enhance the ability of the VSC-HVDC supplementary control, this article proposes a unified low-frequency oscillation controller design using the robustness theory. The unified control strategy uses both the active power control and reactive power control loop of the VSC to expand the supplementary control dimensions. To design the controller, the TLS-ESPRIT identification method is used to obtain the system small signal model and the oscillation characteristic. Based on the model identified out, the linear matrix inequality method based robust control theory is applied for the controller design, and the robust controllers for active power control and reactive power control loop are both designed to improve the control effect. Finally, the simulation results show that the controller can reach better control effect and the robustness can also be guaranteed

A High Precision and Multifunctional Electro‐Optical Conversion Efficiency Measurement System for Metamaterial‐Based Thermal Emitters

In this study, a multifunctional high-vacuum system was established to measure the electro-optical conversion efficiency of metamaterial-based thermal emitters with built-in heaters. The system is composed of an environmental control module, an electro-optical conversion measurement module, and a system control module. The system can provide air, argon, high vacuum, and other conventional testing environments, combined with humidity control. The test chamber and sample holder are carefully designed to minimize heat transfer through thermal conduction and convection. The optical power measurements are realized using the combination of a water-cooled KBr flange, an integrating sphere, and thermopile detectors. This structure is very stable and can detect light emission at the μW level. The system can synchronously detect the heating voltage, heating current, optical power, sample temperatures (both top and bottom), ambient pressure, humidity, and other environmental parameters. The comprehensive parameter detection capability enables the system to monitor subtle sample changes and perform failure mechanism analysis with the aid of offline material analysis using scanning electron microscopy, energy dispersive X-ray spectroscopy, and X-ray diffraction. Furthermore, the system can be used for fatigue and high-low temperature impact tests

Comparison of PET/CT and MRI in the Diagnosis of Bone Metastasis in Prostate Cancer Patients: A Network Analysis of Diagnostic Studies

Background: Accurate diagnosis of bone metastasis status of prostate cancer (PCa) is becoming increasingly more important in guiding local and systemic treatment. Positron emission tomography/computed tomography (PET/CT) and magnetic resonance imaging (MRI) have increasingly been utilized globally to assess the bone metastases in PCa. Our meta-analysis was a high-volume series in which the utility of PET/CT with different radioligands was compared to MRI with different parameters in this setting. Materials and Methods: Three databases, including Medline, Embase, and Cochrane Library, were searched to retrieve original trials from their inception to August 31, 2019 according to the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) statement. The methodological quality of the included studies was assessed by two independent investigators utilizing Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2). A Bayesian network meta-analysis was performed using an arm-based model. Absolute sensitivity and specificity, relative sensitivity and specificity, diagnostic odds ratio (DOR), and superiority index, and their associated 95% confidence intervals (CI) were used to assess the diagnostic value. Results: Forty-five studies with 2,843 patients and 4,263 lesions were identified. Network meta-analysis reveals that 68Ga-labeled prostate membrane antigen (68Ga-PSMA) PET/CT has the highest superiority index (7.30) with the sensitivity of 0.91 and specificity of 0.99, followed by 18F-NaF, 11C-choline, 18F-choline, 18F-fludeoxyglucose (FDG), and 18F-fluciclovine PET/CT. The use of high magnetic field strength, multisequence, diffusion-weighted imaging (DWI), and more imaging planes will increase the diagnostic value of MRI for the detection of bone metastasis in prostate cancer patients. Where available, 3.0-T high-quality MRI approaches 68Ga-PSMA PET/CT was performed in the detection of bone metastasis on patient-based level (sensitivity, 0.94 vs. 0.91; specificity, 0.94 vs. 0.96; superiority index, 4.43 vs. 4.56). Conclusions: 68Ga-PSMA PET/CT is recommended for the diagnosis of bone metastasis in prostate cancer patients. Where available, 3.0-T high-quality MRI approaches 68Ga-PSMA PET/CT should be performed in the detection of bone metastasis

Pore-scale numerical simulation of supercritical CO2-brine two-phase flow based on VOF method

CO2 capture and storage technology is favorable for the reduction of CO2 emissions. In recent years, a great number of research achievements have been obtained on CO2 geological storage from nano scale to oil/gas reservoir scale, but most studies only focus on the flow behaviors in single-dimension porous media. Besides, the physical experiment method is influenced by many uncertain factors and consumes a lot of time and cost. In order to deeply understand the flow behaviors in the process of CO2 geological storage in microscopic view and increase the volume of CO2 geological storage, this paper established 2D and 3D models by using VOF (Volume of Fluid) method which can track the dynamic change of two-phase interface, to numerically simulate supercritical CO2-brine two-phase flow. Then, the distribution characteristics of CO2 clusters and the variation laws of CO2 saturation under different wettability, capillary number and viscosity ratio conditions were compared, and the intrinsic mechanisms of CO2 storage at pore scale were revealed. And the following research results were obtained. First, with the increase of rock wettability to CO2, the sweep range of CO2 enlarged, and the disconnection frequency of CO2 clusters deceased, and thus the volume of CO2 storage increased. Second, with the increase of capillary number, the displacement mode transformed from capillary fingering to stable displacement, and thus the volume of CO2 storage increased. Third, as the viscosity of injected supercritical CO2 gradually approached that of brine, the flow resistance between two-phase fluids decreased, promoting the ''lubricating effect''. As a result, the flow capacity of CO2 phase was improved, and thus the volume of CO2 storage was increased. Fourth, the influence degrees of wettability, capillary number and viscosity ratio on CO2 saturation were different in multi-dimensional porous media models. In conclusion, the CO2-brine two-phase flow simulation based on VOF method revealed the flow mechanisms in the process of CO2 geological storage at pore scale, which is of guiding significance to the development of CCUS technology and provides theoretical guidance and technical support for the study of CO2 geological storage in a larger scale

Cancer-Associated Fibroblasts Regulate Bladder Cancer Invasion and Metabolic Phenotypes through Autophagy

Recently, both cancer-associated fibroblasts (CAFs) and autophagy have been proven to play an important role in tumor development, including bladder cancer (BCa). However, the real mechanisms remain largely unclear. Here, we reconstruct a mimic tumor microenvironment to explore the interaction between CAFs and the BCa cell line T24 using a coculture system. Autophagy in CAFs was induced or inhibited by rapamycin or siRNA, respectively. After coculture with CAFs, T24 cell proliferation, invasion, and aerobic glycolysis were tested in vitro. Rapamycin induced and siAtg5 inhibited autophagy in CAFs. Enhanced autophagy in CAFs promoted cell proliferation and invasion in T24 cells in vitro, while there was no significant difference between the autophagy-inhibited group and the controls. Lactate concentration was elevated in both rapamycin-treated and siAtg5-treated groups compared with the control group. In addition, the expression levels of MCT1, MCT4, HK2, SLC2A1, and MMP-9 were all increased in T24 cells in the autophagy-enhanced group. Our results indicated that CAFs could regulate BCa invasion and metabolic phenotypes through autophagy, providing us with new alternative treatments for BCa in the future

Magnetic order of the La3NiGe2-type Ho3NiGe2

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