205 research outputs found

    Failure characteristic and fracture evolution law of overburden of thick coal in fully mechanized sub-level caving mining

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    In mining process, the height of water flowing fractured zone is important significance to prevent mine of water and gas, in order to further research the failure characteristic of the overlying strata. Taking certain coal mine with 5.82 m mining height as the experimental face, by using the equipment which is sealed two ends by capsules in borehole, affused measurable water between the two capsules and borehole televiewer system, ground penetrating radar, microseismic monitoring system in underground coal mine, the height of water flowing fractured zone of fully-mechanized top caving are monitored, a numerical simulation experiment on the failure process was conducted, a similarity simulation experiment on the cracks evolution was conducted, at the same time, empirical formula of traditional was modified, The results showed that the height of caving and fractured zones were respectively 43.1 and 86.7 m in fully mechanized sub-level caving mining. The data difference of each test method of caving, fractured and water flowing fractured zones were respectively less than 4.5%, 7.1% and 9.0%. The degree of fracture development was low before mining, the number of fissures was obviously increased after mining, the degree of fracture development increased. The fractures cluster region mainly focuses near the coal wall. The fractures density distribution curves of overlying strata like sanke-shapes. The new and adapt to certain coal mine geological conditions empirical formula of water flowing fractured zone height is proposed

    Strong global attractors for a three dimensional nonclassical diffusion equation with memory

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    In this paper, we study the strong global attractors for a three dimensional nonclassical diffusion equation with memory. First, we prove the existence and uniqueness of strong solutions for the equations by the Galerkin method. Then we prove the existence of global attractors for the equations in H2(Ω)∩H01(Ω)×Lμ2(R+;H2(Ω)∩H01(Ω))H^2(\Omega)\cap H^1_0(\Omega)\times L^2_\mu(\mathbb{R}^+;H^2(\Omega)\cap H^1_0(\Omega)) by the condition (C).Comment: 17 page

    HELLaMA: LLaMA-based Table to Text Generation by Highlighting the Important Evidence

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    Large models have demonstrated significant progress across various domains, particularly in tasks related to text generation. In the domain of Table to Text, many Large Language Model (LLM)-based methods currently resort to modifying prompts to invoke public APIs, incurring potential costs and information leaks. With the advent of open-source large models, fine-tuning LLMs has become feasible. In this study, we conducted parameter-efficient fine-tuning on the LLaMA2 model. Distinguishing itself from previous fine-tuning-based table-to-text methods, our approach involves injecting reasoning information into the input by emphasizing table-specific row data. Our model consists of two modules: 1) a table reasoner that identifies relevant row evidence, and 2) a table summarizer that generates sentences based on the highlighted table. To facilitate this, we propose a search strategy to construct reasoning labels for training the table reasoner. On both the FetaQA and QTSumm datasets, our approach achieved state-of-the-art results. Additionally, we observed that highlighting input tables significantly enhances the model's performance and provides valuable interpretability

    Characteristics of cadmium accumulation and tolerance in apple plants grown in different soils

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    Cadmium (Cd) is a nonessential element and highly toxic to apple tree. However, Cd accumulation, translocation and tolerance in apple trees planted in different soils remain unknown. To investigate soil Cd bioavailability, plant Cd accumulation, physiological changes as well as gene expression patterns in apple trees grown in five different soils, ‘Hanfu’ apple seedlings were planted in orchard soils collected from Maliangou village (ML), Desheng village (DS), Xishan village (XS), Kaoshantun village (KS) and Qianertaizi village (QT), and subjected to 500 μM CdCl2 for 70 d. Results showed that soils of ML and XS had higher content of organic matter (OM), clay and silt, and cation exchange capacity (CEC) but lower sand content than the other soils, thereby reduced Cd bioavailability, which could be reflected by lower concentrations and proportions of acid-soluble Cd but higher concentrations and proportions of reducible and oxidizable Cd. The plants grown in soils of ML and XS had relatively lower Cd accumulation levels and bio-concentration factors than those grown in the other soils. Excess Cd reduced plant biomass, root architecture, and chlorophyll content in all plants but to relatively lesser degree in those grown in soils of ML and XS. The plants grown in soils of ML, XS and QT had comparatively lower reactive oxygen species (ROS) content, less membrane lipid peroxidation, and higher antioxidant content and enzyme activity than those grown in soils of DS and KS. Transcript levels of genes regulating Cd uptake, transport and detoxification such as HA11, VHA4, ZIP6, IRT1, NAS1, MT2, MHX, MTP1, ABCC1, HMA4 and PCR2 displayed significant differences in roots of plants grown in different soils. These results indicate that soil types affect Cd accumulation and tolerance in apple plants, and plants grown in soils with higher OM content, CEC, clay and silt content and lower sand content suffer less Cd toxicity

    An 852 nm Faraday laser with 8 kHz linewidth based on corner-cube retroreflector

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    A single-mode Cs atom 852 nm Faraday laser based on the corner-cube reflector feedback is first demonstrated to our best knowledge. Using the corner-cube reflector as external cavity feedback in Faraday laser, the robustness can be greatly improved. This Faraday laser can always achieve laser oscillation unless the angle between incident light and the optical axis of corner-cube retroreflector is beyond the plus or minus 3{\deg} range. Furthermore, the Faraday laser achieves single-mode operation within the current range of 100 mA , and its output wavelength is automatically limited to the vicinity of the Cs atomic transition lines. The wavelength fluctuation range is limited to plus or minus 1.2 pm within 9 hours under +3{\deg} rotation angle. Moreover, the most probable linewidth is 7.97 kHz measured by heterodyne beating. The Faraday laser with high robustness as well as narrow linewidth can be widely used in quantum precision measurement fields including quantum optics, atomic clocks, atomic magnetometers, cold atoms, and atomic gravimeters, etc

    Multiwavelength Er-doped fiber laser using an all-fiber Lyot filter

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    We experimentally demonstrated a multiwavelength Er-doped fiber ring laser system by employing an all-fiber Lyot filter (AFLF) and a highly nonlinear fiber (HNLF). The AFLF was employed as a polarizing filter to generate a nonlinear polarization rotation effect and the highly dense and narrow bandwidth comb-like channels. A 1-km-long HNLF was used to enhance the nonlinearity of the laser cavity and suppress the mode competition for multiwavelength operation. In the experiment, 97 laser output channels within a 3 dB bandwidth simultaneously were excited under 224 mW pump power. The power fluctuation of lasing channels was less than 0.182 dB, and the wavelength shift was less than 0.04 nm in 100 min, after treating the AFLF in a thermostatic ice bath. Meanwhile, the output laser was highly polarized with a degree of polarization up to 99.9%

    Dry eye disease in mice activates adaptive corneal epithelial regeneration distinct from constitutive renewal in homeostasis

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    Many epithelial compartments undergo constitutive renewal in homeostasis but activate unique regenerative responses following injury. The clear corneal epithelium is crucial for vision and is renewed from limbal stem cells (LSCs). Using single-cell RNA sequencing, we profiled the mouse corneal epithelium in homeostasis, aging, diabetes, and dry eye disease (DED), where tear deficiency predisposes the cornea to recurrent injury. In homeostasis, we capture the transcriptional states that accomplish continuous tissue turnover. We leverage our dataset to identify candidate genes and gene networks that characterize key stages across homeostatic renewal, including markers for LSCs. In aging and diabetes, there were only mild changes with \u3c15 dysregulated genes. The constitutive cell types that accomplish homeostatic renewal were conserved in DED but were associated with activation of cell states that comprise adaptive regeneration. We provide global markers that distinguish cell types in homeostatic renewal vs. adaptive regeneration and markers that specifically define DED-elicited proliferating and differentiating cell types. We validate that expression of SPARC, a marker of adaptive regeneration, is also induced in corneal epithelial wound healing and accelerates wound closure in a corneal epithelial cell scratch assay. Finally, we propose a classification system for LSC markers based on their expression fidelity in homeostasis and disease. This transcriptional dissection uncovers the dramatically altered transcriptional landscape of the corneal epithelium in DED, providing a framework and atlas for future study of these ocular surface stem cells in health and disease

    Fractal characteristics of reservoir structural fracture: a case study of Xujiahe Formation in central Yuanba area, Sichuan Basin

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    The reservoir structural fractures have excellent fractal characteristics, as well as self-similarities. Based on the fractal theory, the surface fractal characteristics of faults and the fractal characteristic of fractures in the core of the Xujiahe Formation in the Fault-Fold Belt of the central Yuanba area were studied, and a quantitative relationship was set up between them. Based on the fractal characteristics of faults, predictions were made of the favorable fracture zone, which provides a new idea for the research of fracture, as well as offers theoretical references for exploring the fracture development zone during oil-gas exploration. The results show the following: the seismic value of reflection fault fractal dimension of the Xujiahe Formation is 1.5284; the correlation coefficient R2 is bigger than 0.9901; the capacity dimension linear regression correlation coefficient of the fracture in core of the Xujiahe Formation is bigger than 0.98; the fractal dimension D can well reflect the fault and fracture development degree, as well as the complexity of the fracture system; it can quantitatively calculate the density of the fracture of the reservoir in the area; the areas of capacity dimension bigger than 1.45 are the fracture development zones in the Fault-Fold Belt of the central Yuanba area; the oil and gas enrichment degree is high; the areas with the fractal dimension value between 0.95 and 1.45 are the fracture relatively-developed zones; the fractal dimension with values smaller than 0.95 are the lack of fracture areas.Las fracturas estructurales de yacimientos tienes excelentes características fractales y autosimilares. Basados en la teoría fractal, se estudiaron las características fractales superficiales de las fallas y las características fractales de las fracturas en el núcleo del Cinturón Falla-Pliegue de la Formación Xujiahe, área central de Yuanba (China). Luego se estableció una relación cuantitativa para estas relaciones. Según las características fractales de las fallas, se predijo la zona favorable de fractura, lo que ofrece una nueva idea para el conocimiento de esta y a la vez brinda referencias teóricas para la exploración de la zona de desarrollo de la fractura durante la exploración de petróleo y gas. Los resultados muestran lo siguiente: el valor sísmico de la dimensión fractual de la falla en la Formación Xujiahe es de 1.5284; el coeficiente de correlación R2 es mayor a 0.99901; la dimensión del coeficiente de correlación de regresión lineal en el núcleo de la fractura de la Formación Xujiahe es mayor a 0.98; la dimensión fractal D puede reflejar la falla y el grado de desarrollo de la fractura, al igual que la complejidad del sistema de fractura; también puede calcular cuantitativamente la densidad de la fractura del yacimiento en el área; las áreas con capacidad mayor a 1.45 son las zonas de desarrollo de la fractura en el Cinturón Falla-Pliegue del área central de Yuanba; el grado de enriquecimiento de petróleo y gas es alta; las áreas con valor de dimensión fractal entre 0.95 y 1.45 son las zonas de fractura de desarrollo relativo; la dimensión fractal con valores menos a 0.95 son las áreas que carecen de fracturas

    Herpes Simplex Virus Type 2 Triggers Reactivation of Kaposi's Sarcoma-Associated Herpesvirus from Latency and Collaborates with HIV-1 Tat

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    Kaposi's sarcoma-associated herpesvirus (KSHV) infection was necessary but not sufficient for Kaposi's sarcoma (KS) development without other cofactors. Previously, we identified that both human immunodeficiency type 1 (HIV-1) Tat and herpes simplex virus 1 (HSV-1) were important cofactors reactivating KSHV from latency. Here, we further investigated the potential of herpes simplex virus 2 (HSV-2) to influence KSHV replication and examined the role of Tat in this procedure. We demonstrated that HSV-2 was a potentially important factor in the pathogenesis of KS, as determined by production of lytic phase mRNA transcripts, viral proteins and infectious viral particles in BCBL-1 cells. These results were further confirmed by an RNA interference experiment using small interfering RNA targeting KSHV Rta and a luciferase reporter assay testing Rta promoter-driven luciferase activity. Mechanistic studies showed that HSV-2 infection activated nuclear factor-kappa B (NF-κB) signaling pathway. Inhibition of NF-κB pathway enhanced HSV-2-mediated KSHV activation, whereas activation of NF-κB pathway suppressed KSHV replication in HSV-2-infected BCBL-1 cells. Additionally, ectopic expression of Tat enhanced HSV-2-induced KSHV replication. These novel findings suggest a role of HSV-2 in the pathogenesis of KS and provide the first laboratory evidence that Tat may participate HSV-2-mediated KSHV activation, implying the complicated pathogenesis of acquired immunodeficiency syndrome (AIDS)-related KS (AIDS-KS) patients

    Diammonium Glycyrrhizinate Upregulates PGC-1α and Protects against Aβ1–42-Induced Neurotoxicity

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    Mitochondrial dysfunction is a hallmark of beta-amyloid (Aβ)-induced neurotoxicity in Alzheimer's disease (AD), and is considered an early event in AD pathology. Diammonium glycyrrhizinate (DG), the salt form of Glycyrrhizin, is known for its anti-inflammatory effects, resistance to biologic oxidation and membranous protection. In the present study, the neuroprotective effects of DG on Aβ1–42-induced toxicity and its potential mechanisms in primary cortical neurons were investigated. Exposure of neurons to 2 µM Aβ1–42 resulted in significant viability loss and cell apoptosis. Accumulation of reactive oxygen species (ROS), decreased mitochondrial membrane potential, and activation of caspase-9 and caspase-3 were also observed after Aβ1–42 exposure. All these effects induced by Aβ1–42 were markedly reversed by DG treatment. In addition, DG could alleviate lipid peroxidation and partially restore the mitochondrial function in Aβ1–42-induced AD mice. DG also significantly increased the PGC-1α expression in vivo and in vitro, while knocking down PGC-1α partially blocked the protective effects, which indicated that PGC-1α contributed to the neuroprotective effects of DG. Furthermore, DG significantly decreased the escape latency and search distance and increased the target crossing times of Aβ1–42-induced AD mice in the Morris water maze test. Therefore, these results demonstrated that DG could attenuate Aβ1–42-induced neuronal injury by preventing mitochondrial dysfunction and oxidative stress and improved cognitive impairment in Aβ1–42-induced AD mice, indicating that DG exerted potential beneficial effects on AD
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