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The control of financial risk has always been one of the important topics in financial research. Based on the theory of finance, this paper proposes a kind of financial risk dynamic system. By analyzing some properties of the dynamic system, the system shows obvious coexisting chaotic oscillations. In order to control the financial risk dynamic system effectively, this paper proposes a finite-time impulse controller to control the financial risk dynamic system. Simulation results show that the finite-time impulse controller has faster convergence speed than the impulse controller.

This paper investigates the finite-time synchronization of complex dynamical networks with nondelayed and delayed coupling. By designing a simple continuous function controller, sufficient criteria for finite-time synchronization of dynamical networks with nondelayed and delayed coupling are obtained. As a special case, the continuous function controller designed in this paper may be the simplest and easy to implement for the finite-time synchronization of dynamical networks without delay. Finally, numerical simulations are given to verify the effectiveness of the conclusions presented in this paper.

This paper advances a new single-parameter chaotic system with a simple structure, and some basic dynamic behavior of the new single-parameter system is discussed, such as equilibria, dissipativity, the existence of an attractor, Lyapunov exponent, Poincaré map, spectrum map, and bifurcation diagram. Moreover, a new fixed-time convergence theorem is proposed for general chaotic systems based on finite-time control theory, and a fixed-time controller is also put to achieve synchronization of the new chaotic system. Simulation results are presented to show the effectiveness of the theoretical results. The conclusion of the paper is useful for the nonlinear economics and engineering application.

Since the speed that the $p$ th moment of an output signal norm tends to 0 can be used to measure the quality of the output signal, the stability of the $p$ th moment of complex networks has been widely concerned. This article studies fixed-time synchronization in the $p$ th moment for time-varying delay stochastic multilayer networks, where fixed-time synchronization of multilayer networks is realized by using nonlinear feedback or delay feedback, and the concrete expression of fixed settling time is evaluated. Compared with some existing fixed-time control methods, the optimal combination relationship between the exponential power of fixed-time controllers and the $p$ th moment is given, and the designed controllers are continuous function. Finally, the effectiveness of the method is verified by numerical simulations. [ABSTRACT FROM AUTHOR]

Cancer-associated fibroblasts (CAFs) are crucial components of the tumor microenvironment. Fibroblast activation protein (FAP) is overexpressed in CAFs. FAP-targeted molecular imaging agents, including the FAP inhibitors (FAPIs) 04 and 46, have shown promising results in tumor diagnosis. However, these molecules have a relatively short tumor-retention time for peptide-targeted radionuclide therapy applications. We aimed to design a 68 Ga-labeled FAPI dimer, 68 Ga-DOTA-2P(FAPI) 2 , to optimize the pharmacokinetics and evaluate whether this form is more effective than its monomeric analogs. Methods: 68 Ga-DOTA-2P(FAPI) 2 was synthesized on the basis of the quinoline-based FAPI variant (FAPI-46), and its binding properties were assayed in CAFs. Preclinical pharmacokinetics were determined in FAP-positive patient-derived xenografts using small-animal PET and biodistribution experiments. The effective dosimetry of 68 Ga-DOTA-2P(FAPI) 2 was evaluated in 3 healthy volunteers, and PET/CT imaging of 68 Ga-FAPI-46 and 68 Ga-DOTA-2P(FAPI) 2 was performed on 3 cancer patients. Results: 68 Ga-DOTA-2P(FAPI) 2 was stable in phosphate-buffered saline and fetal bovine serum for 4 h. The FAPI dimer showed high affinity and specificity for FAP in vitro and in vivo. The tumor uptake of 68 Ga-DOTA-2P(FAPI) 2 was approximately 2-fold stronger than that of 68 Ga-FAPI-46 in patient-derived xenografts, whereas healthy organs showed low tracer uptake and fast body clearance. The effective dose of 68 Ga-DOTA-2P(FAPI) 2 was 1.19E-02 mSv/MBq, calculated using OLINDA. Finally, the PET/CT scans of the 3 cancer patients revealed higher intratumoral uptake of 68 Ga-DOTA-2P(FAPI) 2 than of 68 Ga-FAPI-46 in all tumor lesions (SUV max , 8.1-39.0 vs. 1.7-24.0, respectively; P < 0.001). Conclusion: 68 Ga-DOTA-2P(FAPI) 2 has increased tumor uptake and retention properties compared with 68 Ga-FAPI-46, and it could be a promising tracer for both diagnostic imaging and targeted therapy of malignant tumors with positive expression of FAP., (© 2022 by the Society of Nuclear Medicine and Molecular Imaging.)

Purpose: The purpose of this study was to evaluate the differential diagnostic value of 2-[fluorine-18]-fluoro-2-deoxy-d-glucose ( 18 F-FDG) positron emission tomography (PET)/computed tomography (CT) for benign and malignant vertebral compression fractures (VCFs), where the diagnostic accuracy of 18 F-FDG PET/CT was compared with magnetic resonance imaging (MRI)., Patients and Methods: Between 2015 and 2017, we retrospectively evaluated 87 patients with 116 VCFs. MRI was performed in all the 87 patients, whereas 18 F-FDG PET/CT was executed in 51 patients. Three malignant features (convex posterior cortex, epidural mass formation, and pedicle enhancement) from MRI and the maximum standardized uptake value (SUV max ) from 18 F-FDG PET/CT were evaluated in benign and malignant VCFs, respectively. Sensitivity, specificity, positive predictive value, and negative predictive value of MRI and 18 F-FDG PET/CT were compared in the differentiation of malignant from benign VCFs., Results: The results of our investigation showed that the sensitivity and specificity for predicting malignant VCFs were 75.6% and 77.3% for convex posterior cortex, 82.9% and 813% for epidural mass formation, and 85.7% and 70.8% for pedicle enhancement. 18 F-FDG PET/CT demonstrated higher sensitivity (100%) but lower specificity (38.9%) as compared to MRI with regard to differentiation between benign and malignant VCFs. A significant difference in the SUV max values was observed between the benign and malignant fractures (2.9 ± 1.0 vs 5.0 ± 1.8, P < 0.01). Besides the value of SUV max , it has been noticed that the FDG uptake pattern differed in malignant and benign fractures., Conclusion: Significant MRI findings such as convex posterior cortex, epidural mass formation, and pedicle enhancement are highly suggestive of malignancy. 18 F-FDG PET/CT reliably differentiated the fractures of malignant from benign based on both SUV max and 18 F-FDG uptake pattern. In a situation where MRI findings are not diagnostic, 18 F-FDG PET/CT provides additional information as it has high sensitivity and is semiquantitative., Competing Interests: Disclosure The authors report no conflicts of interest in this work.