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We explored Q-switching mechanism for the newly proposed Tm/Ho composite laser via developing a hybrid resonator for separating the intra-cavity Tm laser modulated by the saturable absorber (SA). With a Cr:ZnSe SA, successful passively Q-switching process with the maximum average output power of 474 mW and the shortest pulse width of 145 ns were obtained at the pulse repetition frequency of 7.14 kHz, where dual wavelength oscillation in both 2090 nm and 2097 nm was observed. This work provides an effective way for a direct laser diode (LD) pumped Q-switched Ho laser, which is compact and accessible. Furthermore, the current SA could be replaced by the 2D materials with broadband saturable absorption such as topological insulators or transition-metal dichalcogenides for seeking novel PQS lasers.

Ship lock project currently demonstrates a distinct cyclical pattern, accumulating latent hazards that pose a significant threat to project safety. Seepage safety (the condition in which the seepage risk is reduced to an acceptable level) serves as a crucial indicator in the safety risk assessment index system for ship lock project construction, thus necessitating an in-depth analysis of the risk factors impacting seepage safety. Utilizing a ship lock project in China as a case study, this study employs the finite element method (FEM) to analyze the seepage field of the ship lock foundation pit basin and proposes a comprehensive set of methods for risk evaluation and warning models pertaining to seepage safety risks in ship lock engineering. This study reveals that the obstruction of dewatering wells and imperfections in the diaphragm wall are the primary factors contributing to seepage damage. The investigation conducted a quantitative analysis of the impact of these two factors on the seepage field of the ship lock pit, considering pore pressure, water head, gradient, and flow velocity. A comprehensive set of evaluation indicators for seepage safety was formulated, drawing on the principles of multi-objective optimization, and a method for delineating the safe range of ship lock pit excavation under seepage action was proposed. Subsequently, an integrated seepage safety risk assessment system for ship lock pit excavation engineering was established. These research findings offer a scientific foundation for the management of seepage safety in ship lock pit excavation engineering and provide valuable references and guidance for the development of anti-seepage systems. [ABSTRACT FROM AUTHOR]

Yingxiongling shale oil is considered a critical area for future crude oil production in the Qaidam Basin. However, the unique features of the Yingxiongling area, such as extraordinary thickness, hybrid sedimentary, and extensive reformation, are faced with several challenges, including an unclear understanding of the main controlling factors for hydraulic fracturing propagation, difficulties in selecting engineering sweet layers, and difficulties in optimizing the corresponding fracturing schemes, which restrict the effective development of production. This study focuses on mixed fine-grained sedimentary rocks, employing a high-resolution integrated three-dimensional geological-geomechanical model to simulate fracture propagation. By combining laboratory core experiments, a holistic investigation of the controlling factors was conducted, revealing that hydraulic fracture propagation in mixed fine-grained sedimentary rocks is mainly influenced by rock brittleness, natural fractures, stress, varying lithologies, and fracturing parameters. A comprehensive compressibility evaluation standard was established, considering brittleness, stress contrast, and natural fracture density, with weights of 0.3, 0.23, and 0.47. In light of the high brittleness, substantial interlayer stress differences, and localized developing natural microfractures in the Yingxiongling mixed fine-grained sedimentary rock reservoir, this study examined the influence of various construction parameters on the propagation of hydraulic fractures and optimized these parameters accordingly. Based on the practical application in the field, a "three-stage" stimulation strategy was proposed, which involves using high-viscosity fluid in the front to create the main fracture, low-viscosity fluid with sand-laden slugs to create volume fractures, and continuous high-viscosity fluid carried sand to maintain the conductivity of the fracture network. The resulting oil and gas seepage area corresponding to the stimulated reservoir volume (SRV) matched the actual well spacing of 500 m, achieving the effect of full utilization. The understanding of the controlling factors for fracture expansion, the compressibility evaluation standard, and the main process technology developed in this study effectively guide the optimization of transformation programs for mixed fine-grained sedimentary rocks. [ABSTRACT FROM AUTHOR]

In multivariate and multistep time series prediction research, we often face the problems of insufficient spatial feature extraction and insufficient time-dependent mining of historical series data, which also brings great challenges to multivariate time series analysis and prediction. Inspired by the attention mechanism and residual module, this study proposes a multivariate time series prediction method based on a convolutional-residual gated recurrent hybrid model (CNN-DA-RGRU) with a two-layer attention mechanism to solve the multivariate time series prediction problem in these two stages. Specifically, the convolution module of the proposed model is used to extract the relational features among the sequences, and the two-layer attention mechanism can pay more attention to the relevant variables and give them higher weights to eliminate the irrelevant features, while the residual gated loop module is used to extract the time-varying features of the sequences, in which the residual block is used to achieve the direct connectivity to enhance the expressive power of the model, to solve the gradient explosion and vanishing scenarios, and to facilitate gradient propagation. Experiments were conducted on two public datasets using the proposed model to determine the model hyperparameters, and ablation experiments were conducted to verify the effectiveness of the model; by comparing it with several models, the proposed model was found to achieve good results in multivariate time series-forecasting tasks. [ABSTRACT FROM AUTHOR]

Idebenone, a mitochondrial regulator, has exhibited anti-cancer activity in neurogenic and prostate tumor cells; however, its efficacy and specific targets in the treatment of triple-negative breast cancer (TNBC) remain unclear. This study aims to evaluate the potential of Idebenone as a therapeutic agent for TNBC. TNBC cell lines and Xenograft mouse models were used to assess the effect of Idebenone on TNBC both in vitro and in vivo. To investigate the underlying mechanism of Idebenone's effect on TNBC, cell viability assay, transwell invasion assay, cell cycle analysis, apoptosis assay, mitochondrial membrane potential assay, immunofluorescence staining, and transcriptome sequencing were utilized. The results showed that Idebenone impeded the proliferation, colony formation, migration, and invasion of TNBC cells, suppressed apoptosis, and halted the cell cycle in the G2/M phase. The inhibitory effect of Idebenone on TNBC was associated with the GADD45/CyclinB/CDK1 signaling pathway. By disrupting the mitochondrial membrane potential (MMP) and promoting mitophagy, Idebenone promoted cell autophagy through the AMPK/mTOR pathway, thus further suppressing the proliferation of TNBC cells. Furthermore, we found that Idebenone inhibited the development of TNBC in vivo. In conclusion, Idebenone may be a promising therapeutic option for TNBC as it is capable of inducing autophagy and apoptosis. [ABSTRACT FROM AUTHOR]