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Rock fracture mechanism of buffer blasting with cushion layer at the borehole bottom

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 325-334页

作者： Xinguang Zhu Chenxi Ding Zhe Sui Hong Su Xu guo School of Civil and Resources Engineering University of Science and Technology BeijingBeijing 100083China Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing 100083China School of Chemical and Blasting Engineering Anhui University of Science and TechnologyHuainan 232001China

This study primarily investigates the rock fracture mechanism of bottom cushion layer blasting and explores the effects of the bottom cushion layer on rock *** involves analyses of the evolution patterns of blasting stress,characteristics of crack distribution,and rock fracture features in the ***,blasting model experiments were carried out using the dynamic caustics principle to investigate the influence of bottom cushion layers and initiation methods on the integrity of the bottom rock *** experimental results indicate that the combined use of bottom cushion layers and inverse initiation effectively protects the integrity of the bottom rock ***,the process of stress wave propagation and dynamic crack propagation in rocks was simulated using the continuum-discontinuum element method(CDEM)and the Landau explosion source model,with varying thicknesses of bottom cushion *** numerical simulation results indicate that with increasing cushion thickness,the absorption of energy generated by the explosion becomes more pronounced,resulting in fewer cracks in the bottom rock *** illustrates the positive role of the cushion layer in protecting the integrity of the bottom rock mass.

关键词： bottom cushion layer blasting crack propagation continuum-discontinuum element method dynamic stress intensity factor

NBASS-APS模式在老年颅脑损伤患者围术期疼痛管理中的应用效果分析

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老年医学与保健 2024年第4期30卷 1119-1124页

作者：周秉霞任秀芳高海军郭晓琴山西省汾阳医院病人服务管理科山西汾阳032200 山西省汾阳医院神经外科山西汾阳032200

目的探究以护士为基础,麻醉医师与专科医生指导的急性疼痛服务模式(NBASS-APS)在老年颅脑损伤(TBI)患者围术期疼痛管理中的应用效果,为治疗该病症提供方法。方法纳入2019年3月—2024年3月在山西省汾阳医院治疗的老年TBI患者80例,所有患... 详细信息

目的探究以护士为基础,麻醉医师与专科医生指导的急性疼痛服务模式(NBASS-APS)在老年颅脑损伤(TBI)患者围术期疼痛管理中的应用效果,为治疗该病症提供方法。方法纳入2019年3月—2024年3月在山西省汾阳医院治疗的老年TBI患者80例,所有患者按照随机数表法分为观察组(n=40)和对照组(n=40)。2组在相同治疗的基础上,对照组行常规围术期护理,观察组行NBASS-APS模式下疼痛管理干预。对比2组术后不同时间疼痛程度[采用重症监护疼痛观察工具(CPOT)评估]、神经功能[采用格拉斯哥昏迷评分法(GCS)评估]、术后恢复进程(术后疼痛缓解时间、ICU治疗时间、住院时间),以及护理满意度。结果2组术后7 d CPOT评分达到最低值,且观察组CPOT评分低于对照组(均P<0.05);2组术后3 d、7 d GCS评分升高,观察组GCS评分高于对照组(均P<0.05);观察组术后疼痛缓解时间、ICU治疗时间、住院时间均少于对照组(均P<0.05);观察组护理满意度高于对照组(92.50%vs 67.50%,P<0.05)。结论老年TBI患者接受NBASS-APS模式,可有效缓解老年TBI患者的术后疼痛,改善神经功能,促进术后恢复,并且患者护理满意度较高,具有一定的临床应用价值。

关键词：老年颅脑损伤 NBASS-APS模式疼痛管理

THE SPECTRAL RADIUS OF UNIFORM HYPERGRAPH DETERMINED BY THE SIGNLESS LAPLACIAN MATRIX

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数学杂志 2025年第1期45卷 1-12页

作者： HE Fang-guo College of Mathematics and Statistics Huanggang Normal UniversityHuBei 438000

This paper studies the problem of the spectral radius of the uniform hypergraph determined by the signless Laplacian *** upper bound of the spectral radius of a uniform hypergraph is obtained by using Rayleigh principle and the perturbation of the spectral radius under moving the edge operation,and the extremal hypergraphs are characterized for both supertree and unicyclic *** spectral radius of the graph is generalized.

关键词： spectral radius uniform hypergraph Signless Laplasian matrix

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融合工程实践的现代控制理论课程教学改革

高教学刊 2020年第29期6卷 79-82页

作者：黄苏丹胡智勇曹广忠郭小勤邱洪吴超深圳大学机电与控制工程学院广东深圳518060 深圳大学广东省电磁控制与智能机器人重点实验室广东深圳518060

《现代控制理论》是自动化专业的核心基础课程,具有理论性强、概念抽象、逻辑性强、矩阵公式繁多、与实际系统结合度低等特点。为了提高自动化专业《现代控制理论》的教学质量,提出一种与自动化工程实践相融合的《现代控制理论》教学方... 详细信息

《现代控制理论》是自动化专业的核心基础课程,具有理论性强、概念抽象、逻辑性强、矩阵公式繁多、与实际系统结合度低等特点。为了提高自动化专业《现代控制理论》的教学质量,提出一种与自动化工程实践相融合的《现代控制理论》教学方法,随着每一章节的讲解,将抽象的理论概念与强逻辑性的控制系统分析与设计方法循序渐进地应用到同一个自动化工程实例中,强化学生深入理解抽象的理论知识,提高理论知识与工程实践相结合的能力,从而提高学生对课程的积极参与度以及学生认识、分析、研究和解决自动化工程问题的能力。

关键词：现代控制理论自动化专业工程实践教学改革

Sky location of massive black hole binaries in the foreground of Galactic white dwarf binaries

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 97-108页

作者： Pan guo Hong-Bo Jin Cong-Feng Qiao Yue-Liang Wu The International Centre for Theoretical Physics Asia-Pacific University of Chinese Academy of Sciences The School of Physical Sciences University of Chinese Academy of Sciences Institute for Frontiers in Astronomy and Astrophysics Beijing Normal University National Astronomical Observatories Chinese Academy of Sciences Institute of Theoretical Physics Chinese Academy of Sciences

For space-based gravitational wave （GW） detection,the main noise source for massive black hole binaries （MBHBs） is attributed to approximately 10～7double white dwarf binaries in the *** a GW source,the amplitude of the detector response,recorded by a space-based gravitational wave detector,exhibits a modulation effect with a year period when observing the source from various orbital *** the adverse conditions mentioned above,where there is a strong foreground noise and annual modulation in the signals,we employed the wavelet transform and the strong-amplitude relevant orbital position search methods,which allows the weak MBHB sources to achieve higher locating *** detail,for two MBHB sources of lower intensity,the precision of luminosity distance,represented by the ratio ?DL/DLat the 95%confidence level,is enhanced by factors of ～*** angular resolutions,denoted by??s,are enhanced by a factor of ～*** improvements increase the number of detectable GW sources,facilitate multi-messenger follow-up observations and provide constraints on the cosmological constant.

关键词： space-based gravitational wave detection gravitational waves massive black hole binaries

Viscosity and structure relationship with equimolar substitution of CaO with MgO in the CaO–MgO–Al_(2)O_(3)–SiO_(2)slag melts

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 70-79页

作者： Yong Hou Shuo Zhang Jie Dang Jia guo Hanghang Zhou Xuewei Lü College of Materials Science and Engineering Chongqing UniversityChongqing 400044China Chongqing Key Laboratory of Vanadium-Titanium Metallurgy and New Materials Chongqing UniversityChongqing 400044China

Currently,the Al_(2)O_(3)content in the high-alumina slag systems within blast furnaces is generally limited to 16wt%–18.5wt%,making it challenging to overcome this *** most studies that concentrated on managing the MgO/Al_(2)O_(3)ratio or basicity,this paper explored the effect of equimolar substitution of MgO for CaO on the viscosity and structure of a high-alumina CaO-MgO-Al_(2)O_(3)-SiO_(2)slag system,providing theoretical guidance and data to facilitate the application of high-alumina *** results revealed that the viscosity first decreased and then increased with higher MgO substitution,reaching a minimum at 15mol%MgO *** transform infrared spectroscopy(FTIR)results found that the depths of the troughs representing[SiO_(4)]tetrahedra,[AlO_(4)]tetrahedra,and Si-O-Al bending became progressively deeper with increased MgO *** of the Raman spectra showed that the average number of bridging oxygens per Si atom and the X_(Q^(3))/X_(Q^(2))(X_(Q^(i))is the molar fraction of Q^(i) unit,and i is the number of bridging oxygens in a[SiO_(4)]tetrahedral unit)ratio increased from 2.30 and 1.02 to 2.52 and 2.14,respectively,indicating a progressive polymerization of the silicate structure.X-ray photoelectron spectroscopy(XPS)results highlighted that non-bridging oxygen content decreased from 77.97mol% to 63.41mol% with increasing MgO concentration,whereas bridging oxygen and free oxygen contents *** analysis demonstrated a gradual increase in the polymerization degree of the tetrahedral structure with the increase in MgO ***,bond strength is another important factor affecting the slag *** occurrence of a viscosity minimum can be attributed to the complex evolution of bond strengths of non-bridging oxygens generated during depolymerization of the[SiO_(4)]and[AlO_(4)]tetrahedral structures by CaO and MgO.

关键词： aluminosilicate viscosity structure spectroscopy

Induced neural stem cells regulate microglial activation through Akt-mediated upregulation of CXCR4 and Crry in a mouse model of closed head injury

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Neural Regeneration Research 2025年第5期20卷 1416-1430页

作者： Mou Gao Qin Dong Dan Zou Zhijun Yang Lili guo Ruxiang Xu Department of Neurosurgery Sichuan Academy of Medical Sciences and Sichuan Provincial People’s HospitalSchool of MedicineUniversity of Electronic Science and Technology of ChinaChengduSichuan ProvinceChina Department of Neurosurgery Chinese PLA General HospitalBeijingChina Department of Neurology Fu Xing HospitalCapital Medical UniversityBeijingChina

Microglial activation that occurs rapidly after closed head injury may play important and complex roles in neuroinflammation-associated neuronal damage and *** previously reported that induced neural stem cells can modulate the behavior of activated microglia via CXCL12/CXCR4 signaling,influencing their activation such that they can promote neurological ***,the mechanism of CXCR4 upregulation in induced neural stem cells remains *** this study,we found that nuclear factor-κB activation induced by closed head injury mouse serum in microglia promoted CXCL12 and tumor necrosis factor-αexpression but suppressed insulin-like growth factor-1 ***,recombinant complement receptor 2-conjugated Crry(CR2-Crry)reduced the effects of closed head injury mouse serum-induced nuclear factor-κB activation in microglia and the levels of activated microglia,CXCL12,and tumor necrosis factor-α.Additionally,we observed that,in response to stimulation(including stimulation by CXCL12 secreted by activated microglia),CXCR4 and Crry levels can be upregulated in induced neural stem cells via the interplay among CXCL12/CXCR4,Crry,and Akt signaling to modulate microglial *** agreement with these in vitro experimental results,we found that Akt activation enhanced the immunoregulatory effects of induced neural stem cell grafts on microglial activation,leading to the promotion of neurological recovery via insulin-like growth factor-1 secretion and the neuroprotective effects of induced neural stem cell grafts through CXCR4 and Crry upregulation in the injured cortices of closed head injury ***,these beneficial effects of Akt activation in induced neural stem cells were positively correlated with the therapeutic effects of induced neural stem cells on neuronal injury,cerebral edema,and neurological disorders post–closed head *** conclusion,our findings reveal that Akt activation may enhance the immunoregulatory effects of induced neura

关键词： Akt signaling cerebral edema closed head injury Crry CXCR4 induced neural stem cell microglia neuroinflammation

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穿透性胎盘植入的MRI表现

中华放射学杂志 2015年第11期49卷 833-837页

作者：陈欣单瑞芹王光彬赵连新姚彬史宏璐王姗姗郭小琴卢忠飞李慧华山东大学医学院影像医学与核医学系济南250012 济南市妇幼保健院山东省医学影像学研究所放射科济南250021 山东大学齐鲁医院放射科南昌大学第二附属医院放射科

目的探讨穿透性胎盘植入的MRI征象。方法回顾性分析行胎盘MRI检查且诊断经手术及病理证实的46例患者资料。穿透性胎盘植入19例，非穿透性胎盘植入27例。患者均行胎盘半傅立叶单次激励快速自旋回波（HAsTE）和真实稳态进动快速成像（True... 详细信息

目的探讨穿透性胎盘植入的MRI征象。方法回顾性分析行胎盘MRI检查且诊断经手术及病理证实的46例患者资料。穿透性胎盘植入19例，非穿透性胎盘植入27例。患者均行胎盘半傅立叶单次激励快速自旋回波（HAsTE）和真实稳态进动快速成像（TrueFISP）序列扫描。由2名高年资放射科医师采用双盲法独立分析MRI图像，对MRI征象进行判读。直接征象包括：胎盘聚拢并呈驼峰状改变、膀胱壁呈结节状；间接征象包括：胎盘内低信号带、胎盘内异常血管、胎盘信号显著不均匀、胎盘附着处子宫膨隆、子宫颈内口区胎盘不规则。采用Fisher双侧精确概率检验法比较穿透性和非穿透性胎盘植入患者间各MRI征象出现的差异；以手术病理结果为金标准，计算各MRI征象诊断穿透性胎盘植入的敏感度和特异度。结果胎盘聚拢并呈驼峰状改变、胎盘信号显著不均匀、宫颈内口区胎盘不规则征象在19例穿透性胎盘植入患者中分别出现16、16、12例（医师1），17、14、13例（医师2）；在27例非穿透胎盘植入患者中分别出现7、9、5例（医师1），6、8、5例（医师2）。穿透性和非穿透性胎盘植入患者间上述征象出现的差异均有统计学意义（P均〈0．05）。6例植入至膀胱壁的穿透性胎盘中，4例膀胱壁呈结节状，其余患者均未出现此征象。胎盘聚拢呈驼峰状改变、膀胱壁呈结节状、胎盘内低信号带、胎盘内异常血管、胎盘信号显著不均匀、胎盘附着处子宫膨隆、子宫颈内口区胎盘不规则7种MRI征象鉴别诊断穿透性胎盘植入和非穿透性胎盘植入的敏感度分别为86．9％（33／38）、18．5％（7／38）、89．5％（34／38）、89．5％（34／38）、79．0％（30／38）、94．7％（36／38）和65.8％（25／38），特异度分别为76．0％（41／54）、100．0％（54／54）、37．O％（20／54）、9．3％（5／54）、68．6％（37／54）、11．1％（6／54）和81．5％（44／54）。结论胎盘聚拢并呈驼峰状改变、胎盘信号显著不均匀、宫颈内口区胎盘不规则是诊断穿透性胎盘植人患者有鉴别意义的MRI征象。膀胱壁呈结节状提示胎盘穿透至膀胱壁。

关键词：胎盘,侵入性磁共振成像对比研究

陇中黄土高原气候生产潜力时空变化及水热因子驱动分析

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干旱气象 2015年第5期33卷 861-866页

作者：谢万银郭小芹陆登荣殷玉春王锦波甘肃省气象局甘肃兰州730020

根据陇中黄土高原27个气象台站1971~2013年气象资料,采用Thornthwaite Memorial模型计算气候生产潜力,通过经验正交函数（EOF）方法分析其变化特征。研究表明：研究区域升温明显,降水以及气候生产潜力呈波动性变化,实际产量占气候生产... 详细信息

根据陇中黄土高原27个气象台站1971~2013年气象资料,采用Thornthwaite Memorial模型计算气候生产潜力,通过经验正交函数（EOF）方法分析其变化特征。研究表明：研究区域升温明显,降水以及气候生产潜力呈波动性变化,实际产量占气候生产潜力的43.8%（2000~2013年）,农业开发力度还待大幅提升。气候生产潜力南高北低,纬向分布差异明显;在热量驱动下温度每降低1℃,气候生产潜力减产22 kg·hm-2·a-1;温度每增加1℃,气候生产潜力增产18 kg·hm-2·a-1,热量不足对农业产量有明显抑制作用;在水分驱动下每减少10 mm降水,气候生产潜力将减产11 kg·hm-2·a-1;降水每增加10 mm时,气候生产潜力将增加10 kg·hm-2·a-1。在热量、水分双驱动时气候生产潜力同步叠加了水热条件的共同影响,加大水热供应量将会有效提升农业产量,并且使气候生产潜力差异性变化趋缓。驱动效益分析将陇中黄土高原划分为4个区域,在不同区域农业发展需要因地制宜,区别对待。

关键词：陇中黄土高原气候生产潜力驱动效益