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Based on a large number of field investigations and the analysis of the "analogous hyperbolic" overall movement model proposed by the author, this paper further extends it to three-dimensional space, and proposes a full-space "analogous hyperboloid"three-dimensional movement model of the mining strata.There are two types of hyperboloids, "quasi-single-leaf"and "quasi-double-leaf", which can approximately describe the three-dimensional movement and surface subsidence characteristics of full-space mining strata under different lithological conditions.The "analogous single leaf hyperboloid" model is a horizontal moving boundary model of the spatial rock layer, which is implicit in the thick loose layer overlying rock; the "analogous double leaf hyperboloid" model is the vertical movement of the spatial surface subsidence and the overlying fissure arch and caving arch.The boundary models are approximately symmetrical with the "origin" in the main key layer, and are embodied in external forms such as surface subsidence under mining disturbance and arch caving of the surrounding rock in the stope. Through theoretical analysis, similar model test and 3DEC numerical simulation, this paper deduces and proves in detail the "analogous hyperboloid" model of spatially mined rock strata movement and surface subsidence under the condition of near-horizontal coal seam mining in thick loose layers.At the same time, this study analyzed the composition conditions, influencing factors and overall migration law of the co-asymptotic conical surface "analogous hyperboloid" model.Results show that under the condition of near-horizontal coal seam mining with thin bedrock and thick loose layer, the "quasi-hyperboloid" theoretical model is in good alignment with the 3DEC simulation results, indicating that the overlying rock migration and surface subsidence in space mining are "analogous hyperboloid" feature.

Casings are key components for the aero-engine,and its containment performance is a necessary condition for ensuring flight safety.Firstly,the types and structural forms of the casing related to containment are briefly introduced.Then,the impact response,damage mechanism and containment ability of casings are summarized from aspects of theoretical researches,simulation analyses and experimental tests.Besides,numerical simulation researches about casing containment are introduced according to types of casing material.Test methods about casing containment and its research progresses are analyzed.Finally,the containment research status of casings is summarized and the development tendency of casings containment is looked from the perspective of working condition,loading situations and optimization design.

Abstract It is crucial to enhance the rate capability of the titanium‐based materials for fulfilling their promising potential as the anode materials of sodium‐ion batteries (SIBs). Herein, Mn‐doped sodium titanate (Mn‐NTO) nanowires with homogeneously distributed ultrathin carbon nanosheets (Mn‐NTO@C) are synthesized by a one‐step salt‐template‐assisted method, showing much‐enhanced power density. The as‐prepared Mn‐NTO@C demonstrates the realization of hybrid energy storage, which reconciles the diffusion‐controlled behavior with the pseudocapacitive‐controlled behavior. It has been revealed that the Mn heteroatoms can raise the proportion of Na2Ti3O7 phase with the expanded crystal lattice, facilitating the diffusion‐controlled insertion/extraction process of sodium ions. Meanwhile, the hybrid morphology of Mn‐NTO nanowires and carbon nanosheets provides a promoted structure stability. As a result, the assembled Na||Mn‐NTO@C half‐cells work well at an extreme current density of 24 A g−1 for 10 000 cycles with a capacity retention of 95.2%. Moreover, the Mn‐NTO@C||Na3V2(PO4)3 (NVP) full cells exhibit an attenuation of only 0.0015% per cycle at 20 A g−1 for over 10 000 cycles, and the energy density and power density of the full cells reach an ultrahigh level of 262 Wh kg−1 and 16.3 kW kg−1, respectively.

We are interested in the existence of solutions for the following fractional p (x , ⋅) -Kirchhoff-type problem: { M (∫ Ω × Ω | u (x) − u (y) | p (x , y) p (x , y) | x − y | N + p (x , y) s d x d y) (− Δ) p (x , ⋅) s u = f (x , u) , x ∈ Ω , u = 0 , x ∈ ∂ Ω , where Ω ⊂ R N , N ≥ 2 is a bounded smooth domain, s ∈ (0 , 1) , p : Ω ‾ × Ω ‾ → (1 , ∞) , (− Δ) p (x , ⋅) s denotes the p (x , ⋅) -fractional Laplace operator, M : [ 0 , ∞) → [ 0 , ∞) , and f : Ω × R → R are continuous functions. Using variational methods, especially the symmetric mountain pass theorem due to Bartolo–Benci–Fortunato (Nonlinear Anal. 7(9):981–1012, 1983), we establish the existence of infinitely many solutions for this problem without assuming the Ambrosetti–Rabinowitz condition. Our main result in several directions extends previous ones which have recently appeared in the literature. [ABSTRACT FROM AUTHOR]

OBJECTIVE: We aimed to investigate the biological effects of circRNA_002178 in oral squamous cell carcinoma (OSCC) tissues and to analyze its potential mechanism. PATIENTS AND METHODS: CircRNA_002178 expression in 50 pairs of OSCC tissues and adjacent ones was studied by quantitative polymerase chain reaction (qPCR) analysis, and the correlations of circRNA_002178 with clinicopathological indicators, as wells as prognosis of OSCC patients were analyzed. qPCR was used to verify circRNA_002178 expression in OSCC cell lines. Subsequently, circRNA_002178 knockdown models were constructed using lentivirus in OSCC cell lines, and the impacts of circRNA_002178 on the function of OSCC cells were assessed by cell counting kit-8 (CCK-8) test, plate cloning experiment, transwell assay and nude mouse tumor formation experiments. Finally, rescue experiments in vitro were used to explore the potential mechanism of circRNA_002178 activating Akt/mTOR pathway. RESULTS: Our data showed that circRNA_002178 expression in OSCC tissue specimens was remarkably higher than that in adjacent ones. In comparison to patients in low circRNA_002178 expression group, patients in high expression group showed higher incidences of advanced pathological stage and distant metastasis, and a lower overall survival rate. Cell functional experiments revealed that knockdown of circRNA_002178 markedly attenuated the proliferation and migration ability of OSCC cells compared to the sh-NC group, and the consistent results were observed in the nude mouse experiment. In addition, Western blot suggested that the expression of key proteins in Akt/mTOR signaling pathway was remarkably reduced after downregulation of circRNA_002178 in OSCC cells. Meanwhile, Akt activator SC79 reversed the inhibitory effect of circRNA_002178 on the metastasis and proliferation of OSCC cells. CONCLUSIONS: CircRNA_002178, over-expressed in OSCC tissues and cell lines, may promote the malignant progression of OSCC through activating the Akt/mTOR signaling pathway [ABSTRACT FROM AUTHOR]

This study evaluated effects of three products of dietary organic acids (Acidomix® AFG; Activate® AD and Lacplus) on protective immunity against coccidiosis. Two hundred and eighty 1-day broiler chickens were randomly divided into 8 groups by 5 replications (7 birds per replicate), comprising 2 controls (negative= N; positive=P) and 6 supplemented organic acid groups (1% AFG, 1% DA, 1% Lacplus; 2% AFG, 2% DA and 2% Lacplus). With the exception of N control (uninfected), all 7 groups were orally challenged with 8 x 105 sporulated oocysts of Eimeria tenella at day 12 post-hatch. Samples of blood, spleen and ceca were collected on day 22 and 35 post-hatch. Body weight gain, fecal oocyst shedding, lesion score, mortality rate and pH of the ceca were assessed. ELISA was used to detect Cluster of T cell differentiation (CD4+, CD8+) molecules and reverse transcription polymerase chain reaction (RT-PCR) was employed for detection of pro-inflammatory chemokine (IFNγ-) and cytokines expression (IL-8, IL-15 and IL-17). The result revealed that supplementation of organic acids significantly increased body weight gain, improved feed conversion ratio (FCR), reduced lesion scores and oocyst index (P<0.05) compared to P control (infected non-supplemented). The mortality rate was higher in P control. The pH of ceca was significant (P<0.05) and maximum was observed in P control. Chicks fed 2% DA and 1% Lacplus had greater percentages of CD4 T-cell molecules, but had decreased CD8 T cell molecules, suggesting a protective function of these T-cell subsets in innate immune response against E. tenella infection. The cecal and splenic chemokine and cytokines mRNA expression encoding IFN-γ, IL-8, IL-15 and IL-17 showed higher levels of transcript compared to N and P controls, indicating the organic acid products might have exerted their protective effects by improving their production. It is concluded that the Activate® DA at 2% and Lacplus 1% levels at both 22 and 35-days post-hatch have shown best anticoccidial effects. [ABSTRACT FROM AUTHOR]

The structural evolution, epitaxy, and sublimation temperature of silver nanoclusters (NCs) on TiO2 (110) surfaces prepared in two different ways are reported here based on a combination of in situ reflection high energy electron diffraction characterization and ex situ electron imaging. It is shown that silver NCs deposited at room temperature on oxidized TiO2 (110) surfaces are unable to form a single epitaxy prior to sublimation. When heated close to sublimation, two particle orientations dominate: (111)Ag∥(110)TiO2, [-110]Ag∥[001]TiO2 and (112)Ag∥(110)TiO2, [-110]Ag∥[001]TiO2. Single twinned silver NCs are found to be stable even at temperatures close to sublimation. On the other hand, silver NCs prepared similarly on reduced TiO2 (110) surfaces behave very differently when heated to higher temperatures. On the reduced surface, the NCs are able to evolve into a single epitaxy-(111)Ag∥(110)TiO2, [-110]Ag∥[001]TiO2. The sublimation temperature for silver NCs on the reduced surface is found to be less than those on the oxidized surface by about 35°. The epitaxy formed by annealing is the same as the one formed by depositing silver onto reduced TiO2 (110) at 350 °C (>0.5 Tm of Ag). [ABSTRACT FROM AUTHOR]

We report an in situ study of epitaxial island formation and alloying of FePd nanoparticles using reflection high-energy electron diffraction (RHEED) followed by ex situ atomic structure characterization. We used aberration corrected (AC) scanning transmission electron microscopy (STEM) with a high-angle annular dark field (HAADF) detector for the study of chemical ordering. The FePd nanoparticles were formed by sequential deposition of Pd and Fe onto NaCl substrates, which was then followed by heating to high temperatures to promote chemical ordering during a short period of annealing. We show that the epitaxial island growth and subsequent alloying of Fe into Pd can be clearly detected by RHEED. The high resolution and the atomic number (Z) contrast of AC HAADF-STEM allow a clear observation of nanometer-sized local chemical order in very small nanoparticles. The results revealed complex chemical structures at an intermediate stage of the ordering process with ordered regions of both L10 and L12 phases. [ABSTRACT FROM AUTHOR]

CaF2-structure CoSi2 layers were formed on Si(001) by reactive deposition epitaxy (RDE) and compared with CoSi2 layers obtained by conventional solid phase growth (SPG). In both sets of experiments, Co was deposited by ultrahigh-vacuum magnetron sputtering and CoSi2 formed at 600 °C. However, in the case of RDE, CoSi2 formation occurred during Co deposition while for SPG, Co was deposited at 25 °C and silicidation took place during subsequent annealing. X-ray diffraction pole figures and transmission electron microscopy results demonstrate that RDE CoSi2 layers are epitaxial with a cube-on-cube relationship, (001)CoSi2∥(001)Si and [100]CoSi2∥[100]Si. In contrast, SPG films are polycrystalline with an average grain size of ≃1000 Å and a mixed 111/002/022/112 orientation. We attribute the striking difference to rapid Co diffusion into the Si(001) substrate during RDE for which the high Co/Si reactivity gives rise to a flux-limited reaction resulting in the direct formation of the disilicide phase. In contrast, sequential nucleation and transformation among increasingly Si-rich phases—from orthorhombic Co2Si to cubic CoSi to CoSi2—during SPG results in polycrystalline layers with a complex texture. [ABSTRACT FROM AUTHOR]

We report an experimental investigation on self-assembly of epitaxial Ag nanoclusters on H-terminated Si(111) surfaces. We show that epitaxial Ag clusters of 2-6 nm in diameter can be synthesized by depositing at room temperature, followed by in situ annealing. As-deposited Ag clusters are uniformly distributed on the surface with a well-defined minimum spacing. The Ag clusters are mostly single crystals with Ag(111)//Si(111). The in-plane orientation of the as-grown clusters has a dispersion of ∼9° centering around the Si[110] direction. Upon annealing, most Ag clusters rotate to the epitaxial orientation with Ag[110]//Si[110]. The nanocluster rotation and epitaxy are explained using the coincident site lattice model for the interface structure and interfacial energy minimization. [ABSTRACT FROM AUTHOR]

The surface morphology evolution of amorphous SiO[sub 2] thin films deposited by ultrahigh vacuum radio-frequency magnetron sputtering was studied by atomic force microscopy. The results show that: (1) the surface roughness of the deposited films reduces with increased substrate temperatures; (2) the surface roughness increases with higher deposition pressures; and (3) there is a roughening transition at the critical thickness of ∼ 90 nm for the substrate temperature of 713 K. The results also show that the surface roughness at the early stages of growth evolves according to a power law. Further growth beyond the critical thickness leads to a sharp increase in roughness. The experimental results are compared with the previous theoretical and experimental studies on surface evolution during sputter deposition, and discussed in terms of the competition between surface diffusion and shadowing. [ABSTRACT FROM AUTHOR]

Objective To explore the nursing cooperation process of robot-assisted laparoscopic oral mucosa repair and reconstruction of the ureter. Methods The nursing cooperation of 30 cases of robot-assisted laparoscopic oral mucosa repair and reconstruction of ureter in the Urology Department from December 2020 to December 2021 were analyzed. Intraoperative precision nursing cooperation and postoperative follow-up visits were carried outto ensure the success of surgery and safety of patients during perioperative period. Results The operation was successfully completed in 30 patients, and the overall average success rate was 95. 6%. The effect of medical and nursing cooperation was satisfactory, and no postoperative complications occurred during the short and medium-term follow-up. Conclusion Adequate preoperative preparation, reasonable operating room layout, and skilled intraoperative cooperation are considerable issues of improving the efficiency of the surgeon's operation and are an important part of the successful completion of the operation. (目的 探讨机器人辅助腹腔镜下口腔黏膜修复重建输尿管术的护理配合流程。方法 收集2020年12月—2021年12月行机器人辅助腹腔镜下口腔黏膜修复重建输尿管术治疗的30例患者的临床资料, 总结护理经验, 分析护理要点。结果 30例患者顺利完成手术, 总体平均成功率为 95. 6%。医护配合效果满意, 中短期随访无术后并发症发生。结论 充分的术前准备, 合理的手术间布局, 熟练的术中配合, 有助于能提高术者手术效率, 是确保手术顺利完成的重要环节。)

Pollen analysis is one of the environmental proxies useful for quantitative reconstruction of paleoecology and paleoclimate, and the establishment of a quantitative relationship between surface pollen and vegetation is crucial for accurate interpretation of paleoecology and paleoclimate from fossil pollen. In this study, to explore the relationships between surface pollen assemblages and vegetation and altitude, 113 samples of modern surface pollen and moss were collected from the vertical vegetation zones in central south subtropical China. Based on the results of Canonical Correspondence Analysis (CCA), the study revealed the connections between the distribution of pollen taxa at different elevations and with various climate factors. The main results are as follows: 1) Castanopsis, Quercus-evergreen, Pinus, Cunninghamia and Euphorbiaceae were the dominant pollen taxa of the arbors, and Poaceae, Artemisia, Compositae, and Cyperaceae were the main components of the herbs. Trilete, Dicranopteris, Polypodiaceae and Monolete accounted for a high percentage of the fern pollen. 2) The relationships between pollen taxa and altitude could be divided into three patterns: Castanopsis, Quercus-evergreen, Pinus, Mallotus, Liquidambar, Rubiaceae,and Poaceae were common at the low altitudes (0-702 m). In the medium altitude area (703-1,299 m), there were significant pollen contents in Castanopsis, Cunninghamia, Pinus, Quercus-evergreen, Ericaceae and Pinus. The higher altitude area, at around 1,300-1,600 m, was dominanted by Castanopsis, Quercus-evergreen, and Fagus. Therefore, the distribution of surface pollen is consistent with that of modern vegetation. 3) The results of CCA showed that the climate factors controlling the distribution of surface pollen were Mean Annual Precipitation (MAP), Mean precipitation of warmest season (Mpwa), and Mean temperature of warmest season (Mtwa). It was obvious that the climate characteristics corresponded to high percentage values of various pollen, such as Pinus, Cunninghamia, Castanopsis, Quercus-evergreen, Theaceae, Fagus, and Quercus-deciduous. 4) The significant taxa of Castanopsis, Quercus-evergreen at lower elevations and Pinus, Cunninghamia and Fagus where grow at relatively high area can reflect the effects of climate factors on the spatial distribution of vegetation. Therefore, the results of this study indicated that the surface pollen assemblage varies significantly through the vertical vegetation zones in central south subtropical China. The characteristics of surface pollen dispersal were greatly influenced by the vegetation composition in the region, the habitat, pollen morphology, and the pollen transmission process, which provides a crucial reference for quantitative reconstruction of paleoecology and paleoclimate from fossil pollen data in a subtropical region.

Fibrous plaster (FP) ceilings, prevalent in late 19th- and early 20th-century UK theatres, are suspended using ‘wads’. Wads are hangers made of Plaster of Paris, reinforced with twisted woven jute fabric. Several recent collapses in historic fibrous plaster ceilings have been attributed to tensile failures in wads. To understand the failure mechanisms involved, tensile tests were performed on laboratory-produced wad-like samples at the I12 beamline of the UK Diamond Light Source. The tested samples were designed with a dog bone shape and mounted with clevis-grips at each end, to ensure controlled failures along the gauge length. The beamline offered the opportunity to conduct simultaneous synchrotron X-ray computed tomography (sCT) and diffraction measurements during loading, enabling the monitoring of internal crack formation and strain propagation at the microstructural scale. Simultaneously, acoustic emission (AE) and digital image correlation (DIC) measurements were conducted. Preliminary results from these datasets are discussed in this paper. The datasets will provide useful information to validate the ongoing development of algorithms which can categorise the internal failure mechanisms and damage state of wads using only AE signals.

A flame’s structural feature is a crucial parameter required to comprehensively understand the interaction between turbulence and flames. The generation and evolution processes of the structure feature have rarely been investigated in lean blowout (LBO) flame instability states. Hence, to understand the precursor features of the LBO flame, this work employed high-speed OH-PLIF measurements to acquire time-series LBO flame images and developed a novel feature extraction method based on a deep neural network to quantify the LBO features in real time. Meanwhile, we proposed a deep neural network segmentation method based on a tri-map called the Fire-MatteFormer, and conducted a statistical analysis on flame surface features, primarily holes. The statistical analysis results determined the relationship between the life cycle of holes (from generation to disappearance) and their area, perimeter, and total number. The trained Fire-MatteFormer model was found to represent a viable method for determining flame features in the detection of incipient LBO instability conditions. Overall, the model shows significant promise in ascertaining local flame structure features.

Based on the fracture mechanics theory of the isotropic Hoek-Brown strength criterion, this paper established the initiation conditions of the bifurcated microcrack along bedding which begins with the meso-fracture mechanism of laminated rocks. Then the author substituted the critical angle which indicates that the initial crack most likely causes the fracture of the rock into above established conditions and derived the anisotropy expression of the parameter m1 for the weak plane of bedding leading to the crack deflection. Through introducing the correction coefficient for the mixed fracture of the rock along the bedding and the matrix, this paper obtained the anisotropic modified model of Hoek-Brown strength criterion. Compared with the established anisotropic Hoek-Brown model and shale triaxial test results, the validity of the model was proved. The modified model inherits the fracture mechanics analysis of the isotropic Hoek-Brown strength criterion for the selection of rock failure characteristic quantity, and reflects the microscopic failure mechanism of the rock, also considers the effect of bedding anisotropy. The parameters in the modified criterion have a clear physical meaning. The parameter m in the model is related to the angle of the bedding plane, the tensile strength, compressive strength and friction coefficient of bedding and matrix. The change in the friction coefficient of the bedding plane will cause the position of the minimum value of m and the rock strength characteristics changed.

Rock heterogeneity (such as mineral inclusions, micro-cracks, micro-voids and other microstructures) significantly affects its nonlinear mechanical behavior and failure process. This paper utilizes the Fast Fourier transform-based(FFT) numerical method which does not require meshing of complex microstructure but directly obtains the microstructure of heterogeneous materials through the pixels of the image. In addition, the method can be naturally combined with digital image processing (DIP). An actual-microstructure-based FFT method is thereby developed to simulate the elastoplastic behavior of the heterogeneous rocks under external load. The influence of microstructure on the nonlinear behavior is discussed as well as the internal relationship between the microstructure and the macroscopic mechanical properties. The results show that the real-microstructure-based FFT method can well predict the nonlinear behavior before and after the peak strength of the rocks under different depths and confining pressures. The shape, size and distribution of microstructure directly determine the distribution of stress field in clay rock. The actual-microstructure-based FFT method proposed in this paper can reasonably consider the rock heterogeneity, and provides an important tool for studying the influence of the rock microstructure characteristics on the nonlinear mechanical behavior.

Tap adapter is necessary in online monitoring of transformer bushings to induct current connected to bushing tap. In this paper， earthing structures of transformer bushings in one provincial power grid are investigated. Problems including signal induct， waterproof and durability， open circuit protection， convenience of disassembly and assembly in preventive test and compatibility are handled. Aiming at 3 major earthing structures， 3 types of interface adapters are designed and the safety of transformer bushing tap adapter are studied. The results show that dust-proof， water-proof and vibration resistance performances of the tap adapter meet the national standards； when the bushing tap is open， open circuit protection device of the bushing tap adapter can operate reliably under power frequency and lightning impulse voltage.

In order to realize the smooth collapse of high-strength composite roof in 1311 working face of Zhaozhuang Coal Industry company and avoid strong ground pressure disaster caused by large-area roof suspension, firstly, the composite pressure relief mechanism of “cross cutting and longitudinal explosion” is analyzed theoretically, in other words, the secondary propagation radius r of blasting crack is greatly increased on the basis of fracturing damage length R and explosion crack radius a0, which improves the effect of roof pre-cracking, then, based on the industrial test of 1309 working face, the pressure relief process parameters of “cross cutting and longitudinal explosion” are reasonably determined and applied in the field. The results show that: the “cross cutting and longitudinal blasting” composite pressure relief process can increase the density of borehole axial fractures and borehole radial fractures, and the roof separation of roadway in the application area is low; it shows that the “cross cutting and longitudinal blasting” pressure relief process can effectively destroy the integrity of the roof, reduce the stress concentration of the surrounding rock of the roadway, and play a preventive effect on the strong ground pressure disaster.

Parkinson’s disease (PD) is a neurodegenerative disorder causing severe social and economic burdens. The origin of PD has been usually attributed to mitochondrial dysfunction. To this end, mitochondrial transcription regulators become attractive subjects for understanding PD pathogenesis. Previously, we found that the expression of mitochondrial transcription termination factor 3 (MTERF3) was reduced in MPP+-induced mice model of PD. In the present study, we probe the function of MTERF3 and its role in MPP+-induced cellular model of PD. Initially, we observe that MTERF3 expression is also reduced in MPP+-induced cellular model of PD, which can be mainly attributed to the increase of MTERF3 degradation. Next, we examine the effect of MTERF3 knockdown and overexpression on the replication, transcription, and translation of mitochondrial DNA (mtDNA). We show that knockdown and overexpression of MTERF3 have opposite effects on mtDNA transcript level but similar effects on mtDNA expression level, in line with MTERF3’s dual roles in mtDNA transcription and translation. In addition, we examine the effect of MTERF3 knockdown and overexpression on mitochondrial function with and without MPP+ treatment, and find that MTERF3 seems to play a generally protective role in MPP+-induced mitochondrial dysfunction. Together, this work suggests a regulatory role of MTERF3 in MPP+-induced cellular model of PD and may provide clues in designing novel therapeutics against PD.