This paper investigates the problem of the stock closing price forecasting for the stock market. Based on existing two-stage fusion models in the literature, two new prediction models based on ...clustering have been proposed, where k-means clustering method is adopted to cluster several common technical indicators. In addition, ensemble learning has also been applied to improve the prediction accuracy. Finally, a hybrid prediction model, which combines both the k-means clustering and ensemble learning, has been proposed. The experimental results on a number of Chinese stocks demonstrate that the hybrid prediction model obtains the best predicting accuracy of the stock price. The k-means clustering on the stock technical indicators can further enhance the prediction accuracy of the ensemble learning.
Solid state electrolytes are the key components for high energy density lithium ion batteries and especially for lithium metal batteries where lithium dendrite growth is an inevitable obstacle in ...liquid electrolytes. Solid polymer electrolytes based on a complex of polymers and lithium salts are intrinsically advantageous over inorganic electrolytes in terms of processability and film‐forming properties. But other properties such as ionic conductivity, thermal stability, mechanical modulus, and electrochemical stability need to be improved. Herein, for the first time, 2D additives using few‐layer vermiculite clay sheets as an example to comprehensively upgrade poly(ethylene oxide)‐based solid polymer electrolyte are introduced. With clay sheet additives, the polymer electrolyte exhibits improved thermal stability, mechanical modulus, ionic conductivity, and electrochemical stability along with reduced flammability and interface resistance. The composite polymer electrolyte can suppress the formation and growth of lithium dendrites in lithium metal batteries. It is anticipated that the clay sheets upgraded solid polymer electrolyte can be integrated to construct high performance solid state lithium ion and lithium metal batteries with higher energy and safety.
2D fillers can comprehensively upgrade the performance of solid polymer electrolytes, including thermal and dimensional stability, mechanical strength and elasticity, ionic conductivity, interfacial stability, and operation voltage. 2D fillers are advantageous over 0D and 1D fillers in providing higher effective interface with polymers in solid polymer electrolytes and withstanding the matrix's deformation in the solid polymer electrolytes under external force.
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•CFONC/Li2S6 as binder free electrode for Li-S battery with high sulfur loading.•CFONC as efficient electrocatalyst to facilitate the kinetics of redox reaction.•CFO accelerates ...homogeneous deposition of Li2S on the surface of substrate.•CFONC inhibits the shuttle of polysulfides and thus protects the lithium anode.
Lithium sulfur (Li-S) batteries have been paid more attention to meet the demand of high capacity energy storage. However, most substrates applied to electrodes, which have both high conductivity and full coverage of adsorption-catalysis synergies, are difficult to achieve. Herein, the combination of electrospinning and hydrothermal method is developed to fabricate the composite membrane of ferri-based spinel CoFe2O4 (CFO) loaded nitrogen doped carbon nanofibers (CFONC) applied to positive current collector with Li2S6 catholyte and binder-free of Li-S batteries. Benefiting from the improved catalytic performances in redox reaction of lithium polysulfides due to the abundant active sites which originate from CFO, the CFONC composite with S loading of 4.74 mg exhibits an initial specific discharge capacity of 1096 mAh g−1 at 0.2 C and a high specific discharge capacity of 681 mAh g−1 after 500 cycles with a capacity decay as small as 0.076% per cycle. Even with S loading of 7.11 mg, the cell of CFONC delivers a high initial capacity of 6.1 mAh and maintains 4.8 mAh after 300 cycles. The results show that the efficient chemical anchoring polysulfides and catalyzing redox reaction by multifunctional CFONC composites is a feasible strategy for the large-scale application of lithium sulfur batteries with high performance in the future.
The prognosis of pancreatic cancer (PC) is relatively dismal due to the lack of effective therapy. In this study, we explored the specific functions and molecular mechanisms of miR-107 to uncover ...effective therapeutic targets for PC.
The miR-107 expression in PC cell lines was assessed via quantitative real-time polymerase chain reaction (qRT-PCR). Besides, online bioinformatics analysis was adopted to predict the underlying targets of miR-107. Meanwhile, TCGA database was employed to explore the prognosis of PC patients. In addition, MTT and transwell assays were conducted to explore the PC cells' biological functions.
MiR-107 was remarkably increased in PC cells which could promote the proliferation, invasion and migration of PC cells. In addition, miR-107 could directly down-regulate TGFBR3 expression through binding to TGFBR3 3'UTR. Survival analysis from TCGA suggested that PC patients with higher miR-107 expression was significantly involved in poorer prognosis.
We concluded that miR-107 promoted proliferation, invasion and migration of PC cells via targeting TGFBR3, which may provide novel underlying therapeutic targets.
The concept of cultural capital originated from Pierre Bourdieu’s theoretical hypothesis that explains the different academic achievements of children from different social classes. Different from ...the research paradigms of Karl Marx and Maximilian Weber who conducted social stratification research by analyzing people’s possession of tangible social resources, Bourdieu proposed that cultural capital is also of great significance in social stratification, and social classes use cultural capital to establish stratification and demonstrate the cultural taste and habitus of different classes. In the field of sports practice, families and schools are important fields for the generation and accumulation of cultural capital. When influencing people’s sports behaviors, cultural capital has the characteristics of concealment, stratification, symbolism, and inheritance. Sports culture capital has an important influence on people’s cultural taste and habitus in sports, specifically, on people’s participation, selection, and consumption of sports.
The topic of optimal antisynchronization control for unknown multiagent systems (MASs) with cooperative-competitive (i.e.,coopetition) interaction is challenging because of the complex connection ...characteristics and the coupling among agents. This paper proposes a reinforcement learning Algorithm based on coopetition strength (CS) to achieve optimal antisynchronization in unknown MASs. Firstly, an innovative CS function is explored, and the local state error information of the agents can be redefined. Furthermore, we propose a novel strategy iteration method to approximate the agent’s optimal control policy. Meanwhile, the proposed algorithm’s convergence analysis is presented, which is based on the Lyapunov stability and functional theorem. In the implementation of a data-based control policy, a network structure of actor-critic (AC) is designed. To improve the robustness of the control policy, the target network and experience replay (ER) are introduced in the training process. Finally, the algorithm’s effectiveness is validated using comparable numerical simulations.
Stem cells from human exfoliated deciduous teeth (SHEDs) are highly proliferative, clonogenic, and multipotent stem cells with a neural crest cell origin. This property could be a desirable option ...for potential therapeutic applications. In this study, we focus on the effects of Rho kinase inhibitors Y‐27632 and Noggin on the proliferation of SHEDs and their differentiation into neuron‐like cells. SHEDs were extracted from 10 samples of deciduous teeth obtained from healthy children aged from 5 to 10. The passaged SHEDs were transfected with Noggin, Y‐27632, or their combination. By means of MTT and colony formation assays, the effects of Y‐27632 and Noggin on cell viability and colony formation were detected. Cellular morphology and neurosphere formation were observed under a microscope. Y‐27632 transfection in SHEDs showed enhanced cell viability, colony formation, and neurosphere formation indicating that Y‐27632 could promote cell proliferation of SHEDs. Furthermore, we observed that the SHEDs treated with Noggin in combination with Y‐27632 displayed typical neuron‐like cell morphology and reticular processes. Noggin or Y‐27632 alone or in combination induced obviously increased NSE, Nestin, and GFAP levels, which were highest in SHEDs treated with the combination of Noggin and Y‐27632. These findings suggest that Y‐27632 promotes the proliferation of SHEDs, and Y‐27632 and Noggin in combination have a synergistic effect on promoting differentiation of SHEDs into neuron‐like cells.
This paper presents a novel adaptive dynamic programming (ADP) method to solve the optimal consensus problem for a class of discrete‐time multi‐agent systems with completely unknown dynamics. ...Different from the classical RL‐based optimal control algorithms based on one‐step temporal difference method, a multi‐step‐based (also call n‐step) policy gradient ADP (MS‐PGADP) algorithm, which have been proved to be more efficient owing to its faster propagation of the reward, is proposed to obtain the iterative control policies. Moreover, a novel Q‐function is defined, which estimates the performance of performing an action in the current state. Then, through the Lyapunov stability theorem and functional analysis, the proof of optimality of the performance index function is given and the stability of the error system is also proved. Furthermore, the actor‐critic neural networks are used to implement the proposed method. Inspired by deep Q network, the target network is also introduced to guarantee the stability of NNs in the process of training. Finally, two simulations are conducted to verify the effectiveness of the proposed algorithm.
This paper presents a novel adaptive dynamic programming (ADP) method to solve the optimal consensus problem for a class of discrete‐time multi‐agent systems with completely unknown dynamics. Different from the classical RL‐based optimal control algorithms based on one‐step temporal difference method, a multi‐step‐based (also call n‐step) policy gradient ADP (MS‐PGADP) algorithm, which have been proved to be more efficient owing to its faster propagation of the reward, is proposed to obtain the iterative control policies.
The principle and design of high-resolution sensors are of great significance in the development of fiber-optic sensors. In this article, a general method based on intracavity sensing of fiber ring ...laser (FRL) is proposed for high-resolution measurement, and a high-resolution temperature sensing system is experimentally demonstrated. The theoretical model for intracavity sensing of FRL is presented. In the sensing system, a fiber-optic Sagnac loop is inserted into an FRL for temperature measurement, which performs as the filter and sensing head simultaneously. Because the filter characteristics of the Sagnac loop is modulated by temperature, the intracavity intensity-modulated sensing is induced for the output power of the FRL. With the method based on intracavity sensing, the temperature resolution level of the sensing system has been improved from 10 −3 °C-10 −6 °C. The stability and measurement errors are also measured. The proposed method can be extensible to similar fiber-optic sensors to improve measurement resolution.
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