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We introduce a nonlinear stochastic model reduction technique for high-dimensional stochastic dynamical systems that have a low-dimensional invariant effective manifold with slow dynamics and high-dimensional, large fast modes. Given only access to a black-box simulator from which short bursts of simulation can be obtained, we design an algorithm that outputs an estimate of the invariant manifold, a process of the effective stochastic dynamics on it, which has averaged out the fast modes, and a simulator thereof. This simulator is efficient in that it exploits of the low dimension of the invariant manifold, and takes time-steps of size dependent on the regularity of the effective process, and therefore typically much larger than that of the original simulator, which had to resolve the fast modes. The algorithm and the estimation can be performed on the fly, leading to efficient exploration of the effective state space, without losing consistency with the underlying dynamics. This construction enables fast and efficient simulation of paths of the effective dynamics, together with estimation of crucial features and observables of such dynamics, including the stationary distribution, identification of metastable states, and residence times and transition rates between them. [ABSTRACT FROM AUTHOR]

The eutopic endometrium provides novel insights into endometriotic pathophysiology and treatment. However, no in vivo models currently available are suitable for eutopic endometrium in endometriosis. In this study, we present new endometriotic in vivo models associated with eutopic endometrium using menstrual blood-derived stromal cells (MenSCs). First, we isolated endometriotic MenSCs (E-MenSCs) and healthy MenSCs (H-MenSCs) from the menstrual blood of patients with endometriosis (n = 6) and healthy volunteers (n = 6). Then, we identified MenSCs' endometrial stromal cell properties using adipogenic and osteogenic differentiation. A cell counting kit-8 and wound healing assay were used to compare the proliferation and migration capability between E-MenSCs and H-MenSCs. Seventy female nude mice were used to prepare endometriotic models related to eutopic endometrium by implanting E-MenSCs relying on three approaches, including surgical implantation using scaffolds seeded with MenSCs, and subcutaneous injection of MenSCs in the abdomen and the back (n = 10). H-MenSCs or scaffolds only were implanted in control groups (n = 10). One month after the surgical implantation and 1 week after the subcutaneous injection, we evaluated modeling by hematoxylin–eosin (H&E) and immunofluorescent staining of human leukocyte antigen α (HLAA). Fibroblast morphology, lipid droplets, and calcium nodules in E-MenSCs and H-MenSCs identified their endometrial stromal cell properties. We noticed that the proliferation and migration of E-MenSCs were considerably enhanced compared to H-MenSCs (P < 0.05). E-MenSCs implanted in nude mice formed ectopic lesions using three approaches (n = 10; lesions formation rate: 90%, 115%, and 80%; average volumes: 123.60, 27.37, and 29.56 mm3), while H-MenSCs in the nude mice shaped nothing at the implantation sites. Endometrial glands, stroma, and HLAA expression in these lesions further verified the success and applicability of the proposed endometriotic modeling. Findings provide in vitro and in vivo models and paired controls associated with eutopic endometrium in women with endometriosis using E-MenSCs and H-MenSCs. The approach of subcutaneous injection of MenSCs in the abdomen is highlighted due to non-invasive, simple, and safe steps, a short modeling period (1 week), and an excellent modeling success rate (115%), which could improve the repeats and success of endometriotic nude mice model and shorten the modeling period. These novel models could nearly intimate human eutopic endometrial mesenchymal stromal cells in the progress of endometriosis, opening a new path for disease pathology and treatment. [ABSTRACT FROM AUTHOR]

The aim of this article is the design of a feedforward compensator based on deep reinforcement learning (DRL) for cooperative quadrotors in close crossing flight. Quadrotors are described by state-space models that include shearing airflow disturbance from other quadrotors. This disturbance is compensated in a feedforward way using DRL. Both value based compensator and policy based compensator algorithms are proposed for training purposes. Then, Lyapunov stability criteria are used to prove that the reference trajectory can be tracked boundedly even during the training process of the proposed algorithms, and that a smaller bound of tracking error can be achieved when the compensator converges. An indoor experimental system for online training has been developed for validation purposes. Both simulation and experimental results are provided to demonstrate the effectiveness and advantages of the proposed compensator. [ABSTRACT FROM AUTHOR]

With the rapid development of wireless communication, the requirements of high-integration and low-cost radio frequency (RF) front-end modules in mobile phones result in more usage of silicon-on-insulator field effect transistors (SOIFETs) for the manufacturing of RF switches. However, the nonlinear behavior of SOIFET switches in off-state always produces unwanted harmonics distortion interference when they are excited by a large signal. In this article, we simplify the well-known physics-based surface potential model to an interelectrode nonlinear capacitance (INC) model since it adequately describes the harmonic effects produced by the transistor. The INC model, referred to as the coarse model, cannot match the behavior of the real switch, since many parameters of the switch cannot be accurately determined. This article proposes a novel dynamic neuro-space mapping network model, referred to as the fine model, to optimize the INC model. The proposed model takes advantage of the high accuracy of the fine model and the fast speed of the coarse model. Ultimately, the proposed method can accurately predict the harmonics interference for SOIFET switches in the complex RF front-end environment and provides an intuitive guideline under the design stage to prevent EMI problems. [ABSTRACT FROM AUTHOR]

This document is a correction notice for an article titled "Novel in vivo endometriotic models associated eutopic endometrium by implanting menstrual blood-derived stromal cells from patients with endometriosis" published in Scientific Reports. The correction addresses errors in Figure 5 of the original article. The errors occurred during figure assembly, resulting in duplication of panels and partial duplication of another panel. The corrected version of Figure 5 and its accompanying legend are provided. The authors who contributed equally to the article are listed at the end of the correction notice. [Extracted from the article]

A voltage-variable capacitor is an essential part of the matching element in radio frequency (RF) circuits, including the transmitting and receiving channel of mobile devices. However, the nonlinear characteristic of the voltage-variable capacitor produces unwanted harmonics when driven by a large exciting signal, which causes electromagnetic radiation spurious emission (RSE) complications. This article presents an efficient nonlinear capacitance polynomial model method coupling with harmonics test systems to predict the nonlinear behavior of the voltage-variable capacitor. In addition, a simple neural network model is trained to reduce the need to manually obtain the nonlinear parameters. Moreover, for devices exhibiting strong nonlinearity, an improved long short-term memory (LSTM) network is proposed to predict harmonics. Ultimately, the nonlinear parameter prediction for such devices is obtained quickly by implementing our developed method, which provides intuitive guidance in the design phase. [ABSTRACT FROM AUTHOR]

The  power distribution network (PDN) of a high-speed printed circuit board requires a high-performance power supply. The total equivalent inductance above the top ground plane is an important part of PDN design and is regarded as Labove. In this paper, an inductance library for different structures of capacitor connections and capacitor sizes has been built, which is essential for PDN design. computer simulation technology (CST) and partial element equivalent circuit method are applied to obtain the shorted pattern design curves at various design data. The shorted pattern design curve means the total equivalent inductance varies with the distance between pad and ground plane. In addition, an approximate shorted model is established for a decoupling capacitor-mounted model, which will be convenient for us to get the inductance of Labove. In this paper, the design curve provides an intuitive guideline in designing PDN and facilitates the industry to choose what they want with consideration of the inductance, space, via numbers, etc. [ABSTRACT FROM AUTHOR]