We consider the conjecture of chen and Nie concerning the space forms for canonical metric connections of compact Hermitian manifolds. We verify the conjecture for two special types of Hermitian manifolds: complex nil...
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We consider the conjecture of chen and Nie concerning the space forms for canonical metric connections of compact Hermitian manifolds. We verify the conjecture for two special types of Hermitian manifolds: complex nilmanifolds with nilpotent J, and nonbalanced Bismut torsion-parallel manifolds.
HA/Fe composites were prepared by powder metallurgy. The effects of ball milling time, pressing pressure, and sintering temperature on the porosity and hardness of the composites were investigated, and their mechanica...
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HA/Fe composites were prepared by powder metallurgy. The effects of ball milling time, pressing pressure, and sintering temperature on the porosity and hardness of the composites were investigated, and their mechanical properties and biocompatibility were evaluated. The results show that as the ball milling time increases (30 similar to 60min), the average particle size initially decreases and then increases (82.91 similar to 53.49 similar to 77.98 mu m). Additionally, an appropriate increase in pressing pressure and sintering temperature can decrease the composite's porosity and increase its hardness. When the pressing pressure is 27 KN and the sintering temperature is 1000 degrees C, the composite material has excellent mechanical properties (hardness 268.5 Hv, compressive strength 106.736 MPa) and good in vitro biocompatibility. The hemolysis rate of the sample was 1.719518 %. When the concentration of the extract was 50 %, the cell proliferation rate could reach 136.26 %. Furthermore, the degradation properties of the composites were studied. At 12 months the corrosion rate of HA/Fe composites reached 0.3173 mm/a. It was also observed varying degradation mechanisms was different in different soaking cycles, and the dominant degradation mechanism was gradually changed from HA in the early stage to Fe in the later stage, which played a positive guiding role in the development of iron matrix composites with different degradation rates.
Infrared spectroscopy analysis has found widespread applications in various fields due to advancements in technology and industry *** improve the quality and reliability of infrared spectroscopy signals,deconvolution ...
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Infrared spectroscopy analysis has found widespread applications in various fields due to advancements in technology and industry *** improve the quality and reliability of infrared spectroscopy signals,deconvolution is a crucial preprocessing *** by the transformer model,we propose an Auto-correlation Multi-head attention Transformer(AMTrans)for infrared spectrum sequence *** auto-correlation attention model improves the scaled dot-product attention in the *** utilizes attention mechanism for feature extraction and implements attention computation using the auto-correlation *** auto-correlation attention model is used to exploit the inherent sequence nature of spectral data and to effectively recovery spectra by capturing auto-correlation patterns in the *** proposed model is trained using supervised learning and demonstrates promising results in infrared spectroscopic *** comparing the experiments with other deconvolution techniques,the experimental results show that the method has excellent deconvolution performance and can effectively recover the texture details of the infrared spectrum.
Super-enhancers (SEs) represent a distinct category of cis-regulatory elements notable for their robust transcriptional activation capabilities. In tumor cells, SEs intricately regulate the expression of oncogenes and...
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Super-enhancers (SEs) represent a distinct category of cis-regulatory elements notable for their robust transcriptional activation capabilities. In tumor cells, SEs intricately regulate the expression of oncogenes and pivotal cancer-associated signaling pathways, offering significant potential for cancer treatment. However, few studies have systematically discussed the crucial role of SEs in hepatocellular carcinoma (HCC), which is one of the most common liver cancers with late-stage diagnosis and limited treatment methods for advanced disease. Herein, we first summarize the identification methods and the intricate processes of formation and organization of super-enhancers. Subsequently, we delve into the roles and molecular mechanisms of SEs within the framework of HCC. Finally, we discuss the inhibitors targeting the key SE-components and their potential effects on the treatment of HCC. In conclusion, this review meticulously encapsulates the distinctive characteristics of SEs and underscores their pivotal roles in the context of hepatocellular carcinoma, presenting a novel perspective on the potential of super-enhancers as emerging therapeutic targets for HCC.
A Hermitian-symplectic metric is a Hermitian metric whose K & auml;hler form is given by the (1,1)-part of a closed 2-form. Streets-Tian Conjecture states that a compact complex manifold admitting a Hermitian-symp...
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A Hermitian-symplectic metric is a Hermitian metric whose K & auml;hler form is given by the (1,1)-part of a closed 2-form. Streets-Tian Conjecture states that a compact complex manifold admitting a Hermitian-symplectic metric must be K & auml;hlerian (i.e., admitting a K & auml;hler metric). The conjecture is known to be true in dimension 2 but is still open in dimensions 3 or higher. In this article, we confirm the conjecture for all 2step solvmanifolds, namely, compact quotients of 2-step solvable Lie groups by discrete subgroups. In the proofs, we adopted a method of using special non-unitary frames, which enabled us to squeeze out some hidden symmetries to make the proof go through. Hopefully the technique could be further applied. The proof of the main theorem also gives an explicit description of all Hermitian-symplectic metrics on any 2-step solvable Lie algebra equipped with a complex structure. (c) 2024 Elsevier B.V. All rights are reserved, including those for text and data mining, AI training, and similar technologies.
We consider the conjecture of chen and Nie concerning the space forms for canonical metric connections of compact Hermitian manifolds. We verify the conjecture for two special types of Hermitian manifolds: complex nil...
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In a recent work, Kai Tang conjectured that any compact Hermitian manifold with non-zero constant mixed curvature must be Kähler. He confirmed the conjecture in complex dimension 2 and for Chern Kähler-like ...
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The bandwidth of electromagnetic wave absorbing materials can be broadened by adjusting the magnetic permeability, dielectric constant, thickness, and micro and macro structural designs of the material. Inspired by th...
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The bandwidth of electromagnetic wave absorbing materials can be broadened by adjusting the magnetic permeability, dielectric constant, thickness, and micro and macro structural designs of the material. Inspired by the different resonant frequencies of hollow blocks with varying heights and side lengths, this paper proposes a novel electromagnetic wave absorbing unit structure composed of rotating combinations of hollow blocks with different heights and side lengths. This approach aims to broaden the absorption bandwidth using the same material solely through structural design based on the resonant frequency points of reflection loss. Compared to hollow blocks with a single height and side length, this structure widens the absorption bandwidth and reduces the mass. The structure is fabricated using 3D printing with ABS material that is reinforced with conductive carbon fibers. The designed unit structure in this work exhibits an ultra-wide absorption bandwidth covering the frequency range of 4-40 GHz, with a surface density of merely 0.22 g/cm2. Finally, the synergistic mechanism between the structural design and the resonant frequency points of reflection loss is elucidated, providing a new paradigm for the design of new ultra-wideband electromagnetic absorbing materials.
The influence mechanism of Cu on the corrosion process of low-carbon steel in the salt spray environment has been investigated. In the early stages of corrosion, a Fe-Cu galvanic cell formed between the Fe matrix and ...
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The influence mechanism of Cu on the corrosion process of low-carbon steel in the salt spray environment has been investigated. In the early stages of corrosion, a Fe-Cu galvanic cell formed between the Fe matrix and Cu, which accelerated the corrosion of Fe. As the Fe continues to corrode, Cu is exposed, losing the cathodic protection of Fe and being oxidized to Cu2+, which migrates along the pores of corrosion products onto the surface of the matrix, and is reduced to elemental Cu at the cathode of the Fe-Cu galvanic cell and deposited on the surface of the steel. With the increase in the amount of Cu deposited, a protective film was formed, isolating the metal matrix from O2 and H2O in the corrosive medium, and decreasing the corrosion rate. Therefore, the corrosion mechanism of oxidation-reduction of Cu for Cu-containing steel is proposed in this paper. Additionally, combining with the three corrosion mechanisms previously proposed by the team, a detailed parameterization and simulation analysis of the corrosion process for Cu containing steel was studied using cellular automata. The simulation results successfully replicated the dynamic evolution of Cu corrosion behavior in low-carbon steel.
Accurate perception of the state of health (SOH) of lithium-ion batteries is crucial for their safety and reliable operation. To meet this demand, a recursive feature elimination-deep bidirectional long short-term mem...
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Accurate perception of the state of health (SOH) of lithium-ion batteries is crucial for their safety and reliable operation. To meet this demand, a recursive feature elimination-deep bidirectional long short-term memory (RFE-DBiLSTM) model suitable for partial charging data is proposed to effectively estimate the SOH of lithium- ion batteries. In this study, the recursive feature elimination (RFE) method is used to screen multiple charging features for obtaining the key features that best represent the SOH under two scenarios with different charging segment lengths. Due to the robust noise-filtering capability and strong ability to capture complex and multilevel temporal dependencies, the deep bidirectional long short-term memory (DBiLSTM) model is used for time series data training, verification, and testing during aging. Experimental results show that compared with benchmark time series models such as long short-term memory (LSTM) and gated recurrent unit (GRU), the proposed method significantly reduces the estimated mean absolute error (MAE) and root mean square error (RMSE) on diverse batteries in the above scenarios. In the scenario for missing partial constant current (CC) charging data, the MAE and RMSE of B0005 cell are 0.0062 and 0.0094, the MAE and RMSE of B0006 cell are 0.0294 and 0.0314, the MAE and RMSE of CS2_36 cell are 0.0510 and 0.0601, the MAE and RMSE of B0029 cell are 0.0057 and 0.0072, and the MAE and RMSE of B0030 cell are 0.0088 and 0.0102. This research innovatively combines the RFE method with the DBiLSTM model to improve the accuracy and robustness of SOH estimation.
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