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抖音算法知识视频的生产、表演与规训

未来传播 2024年第1期31卷 40-48页

作者：胡明鑫浙江大学传媒与国际文化学院浙江杭州310058

短视频平台上的算法知识视频逐渐成为人们打破算法想象的窗口和学习内容创作的工具。文章聚焦抖音平台上生产并传播算法知识的视频,采用视觉话语分析和文本分析方法,探究算法知识生产图景及其在整个算法生产网络中的意义。中国语境下,... 详细信息

短视频平台上的算法知识视频逐渐成为人们打破算法想象的窗口和学习内容创作的工具。文章聚焦抖音平台上生产并传播算法知识的视频,采用视觉话语分析和文本分析方法,探究算法知识生产图景及其在整个算法生产网络中的意义。中国语境下,官方与非官方账号共同构成了算法知识生产者。理解算法、迎合算法以及校正算法共同构成算法知识内容,但其同质化与内卷化问题不容忽视。算法知识的生产带有表演性质。算法知识视频具备知识价值,在算法科普方面作发挥了重要作用。但其规训意义显著,通过将平台建构为流量的绝对分配者,将平台算法定义为去中心化,鼓励内容创作者进行算法迎合性生产。从而将算法的不稳定性、内容创作的不确定性责任归咎于内容创作者,维护了平台的家长主义。

关键词：算法知识视频短视频平台知识生产社会表演平台规训

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航空发动机主轴轴承剥落扩展试验

航空发动机 2024年第1期50卷 124-128页

作者：胡铭鑫孔令成赵聪张浩毛宏图中国航发沈阳发动机研究所沈阳110015 中国航发航空发动机动力传输重点实验室沈阳110015

为探索轴承的剥落极限,开展了航空发动机主轴轴承的剥落扩展试验研究。介绍了轴承损伤的形式以及国内外关于疲劳剥落损伤的研究现状;介绍了试验轴承的初始剥落状态以及试验器的基本情况,明确了轴承的润滑条件和监测方式;按照发动机的真... 详细信息

为探索轴承的剥落极限,开展了航空发动机主轴轴承的剥落扩展试验研究。介绍了轴承损伤的形式以及国内外关于疲劳剥落损伤的研究现状;介绍了试验轴承的初始剥落状态以及试验器的基本情况,明确了轴承的润滑条件和监测方式;按照发动机的真实工况和载荷谱制定试验方案并开展试验,定期分解监控轴承的剥落扩展趋势;对试验过程中金属屑末质量分数、轴承温度以及转子振动的监测结果进行了分析。结果表明:小面积剥落的轴承在18 h试验时间内仍能继续工作,轴承温升未发生明显改变,轴承外圈温度大部分时间内保持在150~190℃,但金属屑末质量分数及转子振动时域幅值不断增大,金属屑末累计增长约9500个,振动时域幅值已超过600g。各项参数的监测结果对发动机地面试车或飞行具有重要的参考价值。

关键词：航空发动机主轴轴承剥落扩展试验研究监测方式

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过伸与非过伸型胫骨平台骨折的比较

中国矫形外科杂志 2024年第2期32卷 133-138页

作者：李松生宗淑君胡明鑫张保龙河南中医药大学第五临床医学院(郑州人民医院)骨科河南郑州450003

[目的]探讨过伸型胫骨平台骨折手术方式选择及对预后的影响。[方法]回顾性分析2016年1月—2021年1月本院采用开放复位内固定治疗53例胫骨平台骨折患者。参照Firoozabadi标准分为过伸型组19例,非过伸组34例。比较两组围手术期、随访及影... 详细信息

[目的]探讨过伸型胫骨平台骨折手术方式选择及对预后的影响。[方法]回顾性分析2016年1月—2021年1月本院采用开放复位内固定治疗53例胫骨平台骨折患者。参照Firoozabadi标准分为过伸型组19例,非过伸组34例。比较两组围手术期、随访及影像结果。[结果]过伸组在合并伤的总发生率(63.1%vs 23.4%,P0.05)。随访时间平均(14.3±1.1)个月,两组术后完全负重活动时间的差异无统计学意义(P>0.05)。随时间推移,两组KSS临床评分、KSS功能评分均显著增加(P0.05)。术前过伸型组PTS显著小于非过伸组(P0.05)。[结论]与非过伸型骨折相比,过伸型胫骨平台骨折常合并其他结构损伤,手术治疗复杂,预后较差。

关键词：过伸型胫骨平台骨折合并损伤切开复位内固定预后

Mesenchymal stem cells for repairing glaucomatous optic nerve

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International Journal of Ophthalmology(English edition) 2024年第4期17卷 748-760页

作者： Bai-Yu hu Mei xin ming Chen Ping Yu Liu-Zhi Zeng Eye School of Chengdu University of TCM Chengdu 610000Sichuan ProvinceChina Department of Ophthalmology Chengdu First People’s HospitalChengdu 610095Sichuan ProvinceChina

Glaucoma is a common and complex neurodegenerative disease characterized by progressive loss of retinal ganglion cells(RGCs)and axons.Currently,there is no effective method to address the cause of RGCs degeneration.However,studies on neuroprotective strategies for optic neuropathy have increased in recent years.Cell replacement and neuroprotection are major strategies for treating glaucoma and optic neuropathy.Regenerative medicine research into the repair of optic nerve damage using stem cells has Received considerable attention.Stem cells possess the potential for multidirectional differentiation abilities and are capable of producing RGCfriendly microenvironments through paracrine effects.This article reviews a thorough researches of recent advances and approaches in stem cell repair of optic nerve injury,raising the controversies and unresolved issues surrounding the future of stem cells.

关键词： stem cell glaucoma retinal ganglion cell optic nerve axon regeneration

Preparation of Chemically Recyclable Poly(ether-alt-ester) by the Ring Opening Polymerization of Cyclic Monomers Synthesized by Coupling Glycolide and Epoxides

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Chinese Journal of Polymer Science 2024年第2期42卷 168-175,I0006页

作者： Feng Ren Zhuang-Zhuang Liang ming-xin Niu Chen-Yang hu Xuan Pang Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei230026China

Polyester and polyether are two key oxygenated polymers, and completely alternative sequence of poly(ester-alt-ether) could efficiently combine the advantages(including flexibility, degradability, etc.) of both segments. Currently, despite their copolymers could be synthesized from one-pot mixture of cyclic esters and epoxides, perfectly alternative microstructure is very challenging to realize and typically restricted to certain monomer pairs. Moving forward, synthesizing poly(ester-alt-ether) from commercially available and largescale monomers would be a significant advance. For example, successfully commercialized poly(glycolic acid)(PGA), which is not easily soluble in polymers due to its high crystallinity and is brittle and difficult to control the degradation cycle, would encounter a new paradigm if engineered into poly(ester-altether). In this work, starting from the design of monomer with hybrid structures, we successfully synthesized a series of 1,4-dioxan-2-one containing different substituents based on glycolide(GA) and epoxides using commercially available Salen-Cr(III) and PPNCl catalytic systems.The new monomers underwent ring-opening polymerization(ROP) to form a series of poly(ester-alt-ether) with perfectly alternating glycolic acid and propylene glycol repeat units under catalytic system of thiourea/base. The poly(ester-alt-ether) have significantly lower glass-transition temperature than PGA. Additionally, the poly(ester-alt-ether) can be chemically recovered to monomer using Sn(Oct)2 or 1,8-diazabicyclo[5.4.0]undecane-7-ene(DBU) as a catalyst in solution, thus establishing a closed-loop life cycle. From monomers derived from GA and epoxides, this work furnishes a novel strategy for the synthesis of poly(ester-alt-ether) with chemical recyclability.

关键词： Polyester Polyether Alternative copolymer Ring-opening polymerization

Facile Synthesis of Polyisothioureas via Alternating Copolymerization of Aziridines and Isothiocayanates

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Chinese Journal of Polymer Science 2024年第3期42卷 292-298,I0005页

作者： Hao-Tian Zhang ming-xin Niu Qi Zhang Chen-Yang hu Xuan Pang Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Department of Materials Science and Engineering Jilin UniversityChangchun 130025China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

Isothiourea is an important class of sulfur-containing molecules showing unique catalytic and biological activities. As such,polyisothiourea is envisioned to be an interesting type of polymer that potentially exhibits a number of interesting properties. However, there is no access to synthesizing well-defined polyisothiourea, and currently isothiourea-containing polymers are mainly prepared by immobilizing onto other polymer's side chain. Herein, we report the first facile synthesis of polyisothioureas via alternating copolymerization of aziridines and isothiocayanates. Mediated by the catalytic system of phosphazene superbases/alcohol, a broad scope of aziridines and isothiocayanates could be transformed into polyisothioureas with adjustable substitutions(11 examples). The structures of obtained polyisothioureas were fully characterized with ^(1)H-NMR, ^(13)C-NMR, and ^(1)H-^(13)C HMBC NMR. Moreover, the polyisothioureas show tunable thermal properties depending on substitutions on the isothiourea linkages. The novel structure of these polyisothioureas will enable a powerful platform for the discovery of nextgeneration functional plastics.

关键词： Polyisothioureas Alternative copolymer Aziridines Isothiocayanates

双系统冗余热备EtherCAT主站的设计与实验

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计算机技术与发展 2024年第4期34卷 1-6页

作者：胡鑫明蒋大海任艳兵巩芫芳魏超西安西电数字科技有限公司陕西西安710075 西安西电电力系统有限公司陕西西安710075

EtherCAT总线技术凭借低成本、高性能的优势已广泛应用于工业控制领域。针对目前EtherCAT主站产品普遍无法同时满足线缆冗余和热备份运行,设计了一种双系统冗余热备主站方案。该主站设备由2个主站模块与1个冗余控制模块协同工作,主站模... 详细信息

EtherCAT总线技术凭借低成本、高性能的优势已广泛应用于工业控制领域。针对目前EtherCAT主站产品普遍无法同时满足线缆冗余和热备份运行,设计了一种双系统冗余热备主站方案。该主站设备由2个主站模块与1个冗余控制模块协同工作,主站模块负责控制网络中的从站设备,冗余控制模块在监视主站模块并仲裁其激活/备用状态的同时还通过其内部网口切换组件控制仅激活的主站模块接入网络。方案中主站模块基于龙芯微处理器设计,冗余控制模块基于意法半导体微控制器设计,所选用的主要软件如实时操作系统(SylixOS,RT-Thread)以及协议栈(SOME,libmodbus)均为开源产品。最后对所设计的主站设备进行测试验证,结果证明该主站功能完整性能优秀,既保留了线缆冗余机制还实现了双系统冗余热备份运行,能够在激活系统故障后毫秒级时间完成系统切换,可靠性满足大多数工业控制应用场景对主站控制器的要求。

关键词： EtherCAT主站双系统冗余热备份 SylixOS RT-Thread SOEM

PRP联合关节镜下肩峰成形术治疗肩峰下撞击综合征的效果及安全性研究

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海南医学 2024年第11期35卷 1600-1603页

作者：张保龙程威胡燕宗淑君崔瑞开胡明鑫尤笑迎河南中医药大学第五临床医学院(郑州人民医院)骨三科河南郑州453000

目的探讨富血小板血浆(PRP)联合关节镜下肩峰成形术治疗肩峰下撞击综合征(SIS)的效果及安全性。方法选择2020年1月至2023年1月河南中医药大学第五临床医学院(郑州人民医院)收治的80例SIS患者作为研究对象,按照随机数表法分为观察组和对... 详细信息

目的探讨富血小板血浆(PRP)联合关节镜下肩峰成形术治疗肩峰下撞击综合征(SIS)的效果及安全性。方法选择2020年1月至2023年1月河南中医药大学第五临床医学院(郑州人民医院)收治的80例SIS患者作为研究对象,按照随机数表法分为观察组和对照组各40例。对照组患者采用关节镜下肩峰成形术治疗,观察组患者在对照组的基础上联合PRP治疗。比较两组患者治疗前、治疗后3个月的肩功能(前屈、外展、内外旋转的活动度)、肩手综合征评估量表(SHSS)评分、上肢Fugl-Meyer运动功能(FMA)评定量表评分、视觉模拟评分法(VAS)评分、炎症因子[白细胞介素-1(IL-1)、白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)]的水平变化,并记录治疗后所发生的并发症。结果观察组患者治疗后的肩部前屈、外展、内外旋转的活动度分别为(129.14±11.58)°、(111.02±22.57)°、(67.20±12.55)°、(65.36±13.31)°,明显高于对照组的(122.31±10.62)°、(100.15±15.63)°、(55.09±12.10)°、(54.01±12.14)°,差异均有统计学意义(P<0.05);观察组患者治疗后的SHSS评分、VAS评分分别为(4.63±0.79)分、(3.02±0.74)分,明显低于对照组的(5.78±1.14)分、(3.89±0.83)分,上肢FMA评分为(36.52±3.60)分,明显高于对照组的(31.56±3.18)分,差异均有统计学意义(P<0.05);观察组患者治疗后的血清IL-1、IL-6、TNF-α水平分别为(1.15±0.16)μg/L、(0.64±0.20)μg/L、(2.10±0.44)μg/L,明显低于对照组的(1.63±0.18)μg/L、(0.95±0.24)μg/L、(2.89±0.48)μg/L,差异均有统计学意义(P<0.05);观察组患者的皮下血肿、发热、疼痛的发生率分别为5.00%、2.50%、2.50%,明显低于对照组的20.00%、15.00%、17.50%,差异均有统计学意义(P<0.05)。结论PRP联合关节镜下肩峰成形术能有效改善SIS患者的肩关节功能,促进肢体功能康复,降低炎症的水平表达,安全性高。

关键词：肩峰下撞击综合征关节镜肩峰成形术富血小板血浆肩功能

Construction and validation of a neovascular glaucoma nomogram in patients with diabetic retinopathy after pars plana vitrectomy

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World Journal of Diabetes 2024年第4期15卷 654-663页

作者： Yi Shi Yan-xin Zhang ming-Fei Jiao xin-Jun Ren Bo-Jie hu Ai-hua Liu Xiao-Rong Li Surgical Retina Tianjin Key Laboratory of Retinal Functions and DiseasesTianjin Branch of National Clinical Research Center for Ocular DiseaseEye Institute and School of OptometryTianjin Medical University Eye HospitalTianjin 300384China Glaucoma Tianjin Key Laboratory of Retinal Functions and DiseasesTianjin Branch of National Clinical Research Center for Ocular DiseaseEye Institute and School of OptometryTianjin Medical University Eye HospitalTianjin 300384China Ocular Trauma Tianjin Key Laboratory of Retinal Functions and DiseasesTianjin Branch of National Clinical Research Center for Ocular DiseaseEye Institute and School of OptometryTianjin Medical University Eye HospitalTianjin 300384China

BACKGROUND Neovascular glaucoma(NVG)is likely to occur after pars plana vitrectomy(PPV)for diabetic retinopathy(DR)in some patients,thus reducing the expected benefit.Understanding the risk factors for NVG occurrence and building effective risk prediction models are currently required for clinical research.AIM To develop a visual risk profile model to explore factors influencing DR after surgery.METHODS We retrospectively selected 151 patients with DR undergoing PPV.The patients were divided into the NVG(NVG occurrence)and No-NVG(No NVG occurrence)groups according to the occurrence of NVG within 6 months after surgery.Independent risk factors for postoperative NVG were screened by logistic regression.A nomogram prediction model was established using R software,and the model’s prediction accuracy was verified internally and externally,involving the receiver operator characteristic curve and correction curve.RESULTS After importing the data into a logistic regression model,we concluded that a posterior capsular defect,preoperative vascular endothelial growth factor≥302.90 pg/mL,glycosylated hemoglobin≥9.05%,aqueous fluid interleukin 6(IL-6)≥53.27 pg/mL,and aqueous fluid IL-10≥9.11 pg/mL were independent risk factors for postoperative NVG in patients with DR(P<0.05).A nomogram model was established based on the aforementioned independent risk factors,and a computer simulation repeated sampling method was used to internally and externally verify the nomogram model.The area under the curve(AUC),sensitivity,and specificity of the model were 0.962[95%confidence interval(95%CI):0.932-0.991],91.5%,and 82.3%,respectively.The AUC,sensitivity,and specificity of the external validation were 0.878(95%CI:0.746-0.982),66.7%,and 95.7%,respectively.CONCLUSION A nomogram constructed based on the risk factors for postoperative NVG in patients with DR has a high prediction accuracy.This study can help formulate relevant preventive and treatment measures.

关键词： Diabetic retinopathy Retinopathy Neovascular Glaucoma Risk factors Nomogram