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A lightweight symmetric image encryption cryptosystem in wavelet domain based on an improved sine map
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作者 陈柏池 黄林青 +2 位作者 蔡述庭 熊晓明 张慧 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期266-276,共11页
In the era of big data,the number of images transmitted over the public channel increases exponentially.As a result,it is crucial to devise the efficient and highly secure encryption method to safeguard the sensitive ... In the era of big data,the number of images transmitted over the public channel increases exponentially.As a result,it is crucial to devise the efficient and highly secure encryption method to safeguard the sensitive image.In this paper,an improved sine map(ISM)possessing a larger chaotic region,more complex chaotic behavior and greater unpredictability is proposed and extensively tested.Drawing upon the strengths of ISM,we introduce a lightweight symmetric image encryption cryptosystem in wavelet domain(WDLIC).The WDLIC employs selective encryption to strike a satisfactory balance between security and speed.Initially,only the low-frequency-low-frequency component is chosen to encrypt utilizing classic permutation and diffusion.Then leveraging the statistical properties in wavelet domain,Gaussianization operation which opens the minds of encrypting image information in wavelet domain is first proposed and employed to all sub-bands.Simulations and theoretical analysis demonstrate the high speed and the remarkable effectiveness of WDLIC. 展开更多
关键词 image encryption discrete wavelet transform 1D-chaotic system selective encryption Gaussianization operation
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Prospective randomized study to evaluate and compare the post-procedural sexual function in patients undergoing semi-rigid ureterorenoscopy for distal ureteric stones in three different operating room settings
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作者 Gajanan S.Bhat Anuradha Shastry 《Asian Journal of Urology》 CSCD 2024年第2期331-338,共8页
Objective:To evaluate and compare the effect of semi-rigid ureterorenoscopy on post-procedural sexual function with three different operating room settings.Methods:In this prospective randomized study,consecutive sexu... Objective:To evaluate and compare the effect of semi-rigid ureterorenoscopy on post-procedural sexual function with three different operating room settings.Methods:In this prospective randomized study,consecutive sexually active patients with normal pre-operative sexual function undergoing uncomplicated semi-rigid ureterorenoscopy for distal ureteric stones were randomized into three groups,with three different operating room settings.Procedure-related anxiety and sexual function were assessed pre-operatively using Amsterdam Preoperative Anxiety and Information Scale and Brief Sexual Function Inventory(in males)and Female Sexual Function Index-6(in females),respectively.All the participants were stented following the procedure,and the stent was removed after 3 weeks.Post-procedural sexual function and general discomfort were assessed and compared between three groups at 1 week,3 weeks,and 12 weeks.The effect of surgery-related anxiety,preoperative sexual function,age,and general discomfort(including stent-related discomfort)on post-procedural sexual function were analyzed using multiple regression analysis.A p-value of less than 0.05 was considered statistically significant.Results:Totally,327 eligible patients were randomized into three groups.The group of patients who underwent the procedural with a screen separating the operating area from the patient vision,while the patient could watch the endoscopy through a separate monitor,had better post-procedural sexual function compared to those who had total vision of the operating area as well as to those whose eyes were blocked.This difference was statistically significant.This post-procedural reduction in sexual function could not be attributed to in situ stent alone.Conclusions:Our study showed that semi-rigid ureterorenoscopy can have significant negative effect on sexual function,which can be reduced with proper preoperative counseling and an ideal operating room settings. 展开更多
关键词 Semi-rigid ureterorenoscopy Post-procedural sexual dysfunction Preoperative counselling operating room setting
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The Impact of Optimizing Details in the Operating Room on the Level of Knowledge, Attitude, and Practice of Hospital Infection Prevention and Control by Surgeons, as Well as the Effectiveness of Infection Control
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作者 Yuanyuan Zhang 《Surgical Science》 2024年第7期421-429,共9页
Objective: This paper aims to explore the impact of optimizing details in the operating room on the level of knowledge, attitude, and practice of hospital infection prevention and control by surgeons, as well as the e... Objective: This paper aims to explore the impact of optimizing details in the operating room on the level of knowledge, attitude, and practice of hospital infection prevention and control by surgeons, as well as the effectiveness of infection control. Methods: From January 2022 to June 2023, a total of 120 patients were screened and randomly divided into a control group (routine care and hospital infection management) and a study group (optimizing details in the operating room). Results: Significant differences were found between the two groups in the data of surgeons’ level of knowledge, attitude, and practice in hospital infection prevention and control, infection rates, and nursing satisfaction, with the study group showing better results (P Conclusion: The use of optimizing details in the operating room among surgeons can effectively improve surgeons’ level of knowledge, attitude, and practice in hospital infection prevention and control, reduce infection occurrence, and is worth promoting. 展开更多
关键词 Optimizing Details in the operating Room Infection Level of Knowledge ATTITUDE and Practice Infection Control
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Aero-Hydro-Elastic-Servo Modeling and Dynamic Response Analysis of A Monopile Offshore Wind Turbine Under Different Operating Scenarios
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作者 XIE Shuang-yi GAO Jian +3 位作者 LI Yong-ran JIANG Shu-xin ZHANG Cheng-lin HE Jiao 《China Ocean Engineering》 SCIE EI CSCD 2024年第3期379-393,共15页
This paper constructs a coupled aero-hydro-elastic-servo simulation framework for a monopile offshore wind turbine(OWT).In this framework,a detailed multi-body dynamics model of the monopile OWT including the gearbox,... This paper constructs a coupled aero-hydro-elastic-servo simulation framework for a monopile offshore wind turbine(OWT).In this framework,a detailed multi-body dynamics model of the monopile OWT including the gearbox,blades,tower and other components(nacelle,hub,bedplate,etc.)has been explicitly established.The effects of pile−soil interaction,controller and operational conditions on the turbine dynamic responses are studied systematically in time domain and frequency domain.The results show that(1)a comprehensive drivetrain model has the capability to provide a more precise representation of the complex dynamic characteristics exhibited by drivetrain components,which can be used as the basis for further study on the dynamic characteristics of the drivetrain.(2)The pile−soil interaction can influence the wind turbine dynamic responses,particularly under the parked condition.(3)The effect of the pile−soil interaction on tower responses is more significant than that on blade responses.(4)The use of the controller can substantially affect the rotor characteristics,which in turn influences the turbine dynamic responses.(5)The tower and blade displacements under the operational condition are much larger than those under the parked condition.The model and methodology presented in this study demonstrate potential for examining complex dynamic behaviors of the monopile OWTs.To ensure accuracy and precision,it is imperative to construct a detailed model of the wind turbine system,while also taking into account simulation efficiency. 展开更多
关键词 offshore wind turbine(OWT) pile−soil interaction dynamic response parked condition operating condition
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Research and design of an expert diagnosis system for rail vehicle driven by data mechanism models
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作者 Lin Li Jiushan Wang Shilu Xiao 《Railway Sciences》 2024年第4期480-502,共23页
Purpose-The aim of this work is to research and design an expert diagnosis system for rail vehicle driven by data mechanism models.Design/methodology/approach-The expert diagnosis system utilizes statistical and deep ... Purpose-The aim of this work is to research and design an expert diagnosis system for rail vehicle driven by data mechanism models.Design/methodology/approach-The expert diagnosis system utilizes statistical and deep learning methods to model the real-time status and historical data features of rail vehicle.Based on data mechanism models,it predicts the lifespan of key components,evaluates the health status of the vehicle and achieves intelligent monitoring and diagnosis of rail vehicle.Findings-The actual operation effect of this system shows that it has improved the intelligent level of the rail vehicle monitoring system,which helps operators to monitor the operation of vehicle online,predict potential risks and faults of vehicle and ensure the smooth and safe operation of vehicle.Originality/value-This system improves the efficiency of rail vehicle operation,scheduling and maintenance through intelligent monitoring and diagnosis of rail vehicle. 展开更多
关键词 Rail transit Rail vehicle Expert diagnosis Intelligent operation and maintenance Deep learning Lifespan prediction Reliability analysis
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Correlation between critical thinking and emotional intelligence:a national crosssectional study on operating room nursing students in Iran
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作者 Armin Fereidouni Esmaeil Teymoori +3 位作者 Tayebeh Bahmani Hamid Reza Sabet Zahra Maleki Mina Gharibi 《Frontiers of Nursing》 2024年第1期99-104,共6页
Objective:According to the World Federation of Medical Education,critical thinking should be part of the training of medical and paramedical students.Professionals can improve the quality of care of patients after sur... Objective:According to the World Federation of Medical Education,critical thinking should be part of the training of medical and paramedical students.Professionals can improve the quality of care of patients after surgery by having or acquiring this skill in health care.Also,Emotional intelligence is introduced as an impor tant and effective factor on the professional performance and mental health of healthcare professionals.Thus,the present study was designed and implemented to determine the relationship between emotional intelligence and critical thinking among operating room nursing students of medical sciences universities in Iran.Methods:This cross-sectional study was done on 420 operating room students in 10 top medical sciences universities of Iran in 2022.The sampling method in this research was multistage sampling.The data collection instruments included demographic characteristics,Rickett's critical thinking,and Bradberry-Greaves'emotional intelligence questionnaires.After receiving the ethics code,data collection was done for 2 months.For data analysis,descriptive and inferential analyses including independent t-tests,analysis of variance,and Pearson correlation were used.The collected data were analyzed by SPSS 18(IBM Corporation,Armonk,New York,United States).P-value<0.05 was considered significant.Results:The mean age of the students participating in this study was 23.02±3.70 years,with women constituting 67.4%of them.The results of data analysis indicated that the mean total score of critical thinking and emotional intelligence was 124.10±37.52 and 114.12±43.63,respectively.A direct significant correlation between critical thinking and emotional intelligence(r=0.459,P-value<0.001)and a significant relationship between gender and emotional intelligence(P-value=0.028)were found.Conclusions:Based on the present study results,educational managers in the Ministry of Health are suggested to consider suitable educational programs for improving critical thinking and emotional intelligence to enhance the quality of care provided by students in operating rooms. 展开更多
关键词 critical thinking emotional intelligence operating room students operating room nurses
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Application of Nursing Cooperation Path in Operating Room and Analysis of Complication Rate During Laparoscopic Hysterectomy
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作者 Xiaohong Shen 《Journal of Clinical and Nursing Research》 2024年第1期222-227,共6页
Objective:To explore the clinical benefits achieved by implementing the operating room nursing cooperation path for patients undergoing laparoscopic hysterectomy.Methods:64 laparoscopic hysterectomy cases were divided... Objective:To explore the clinical benefits achieved by implementing the operating room nursing cooperation path for patients undergoing laparoscopic hysterectomy.Methods:64 laparoscopic hysterectomy cases were divided into groups according to the order of admission.The control group received routine perioperative care.The observation group implemented the nursing cooperation path in the operating room on the same basis as the control group.The two groups’physiological responses,stimulus indicators,anxiety,and complication rates were compared.Results:The heart rate,blood pressure 0.5 hours after surgery,anxiety scores 1 day before and 3 days after surgery,and the total number of complications in the observation group were all lower than those in the control group(P<0.05).Conclusion:The development of a nursing cooperation path in the operating room can help patients undergoing laparoscopic hysterectomy reduce heart rate,blood pressure,stress responses,and the risk of complications,and is worthy of promotion. 展开更多
关键词 Laparoscopic hysterectomy operating room nursing cooperation path COMPLICATIONS
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青海东昆仑三通沟北锰矿成矿时代与物质来源:来自Re-Os同位素年代学与地球化学的约束
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作者 李文 刘永乐 +4 位作者 李文君 高炳宇 董志国 朱明田 张连昌 《岩石学报》 SCIE EI CAS CSCD 北大核心 2024年第4期1231-1248,共18页
东昆仑三通沟北锰矿床是近年来青海省发现的规模最大的海相沉积型锰矿。该矿床位于东昆南构造带的北缘,成矿地质背景与原特提斯洋的演化密切相关。但目前该矿床研究程度较低,尤其是成矿时代存在中-新元古代与奥陶-志留纪的争议,成矿物... 东昆仑三通沟北锰矿床是近年来青海省发现的规模最大的海相沉积型锰矿。该矿床位于东昆南构造带的北缘,成矿地质背景与原特提斯洋的演化密切相关。但目前该矿床研究程度较低,尤其是成矿时代存在中-新元古代与奥陶-志留纪的争议,成矿物质来源存在海底热液为主还是海底热液与陆源风化共同来源的不同认识。为了解决这些问题,本文在对三通沟北锰矿进行详细野外地质调查和钻孔岩芯编录的基础上,选择11件锰矿石进行Re-Os同位素分析,获得了442±15Ma的Re-Os等时线年龄,说明三通沟北锰矿带形成于晚奥陶世,不是前人认为的中-新元古代,这一成矿年龄与区域上的奥陶纪纳赤台群沉积岩的形成时代一致。同时Re-Os同位素分析获得的^(187)Os/^(188)Os初始值为0.67±0.02,该值明显低于同期海水的Os同位素组成(0.72),初步表明三通沟北锰矿的锰质来源以海底热液为主。矿石在SiO_(2)-Al_(2)O_(3)、Al/(Al+Fe+Mn)-Fe/Ti、Fe-Mn-(Ni+Cu+Co)×10和lgU-lgTh等图解上主要位于热水沉积区,矿石稀土元素配分型式也具有海底热液来源的特征。可见三通沟北锰矿的成矿物质来源主要与海底热液活动有关。 展开更多
关键词 东昆仑 沉积型锰矿 纳赤台群 RE-os同位素年龄 地球化学
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新疆东天山黄滩金铜锌矿成矿时代——来自白云母^(40)Ar-^(39)Ar年龄和黄铁矿Re-Os年龄约束
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作者 耿新霞 张志欣 +4 位作者 张振龙 李宁 杨富全 杨成栋 成曦晖 《大地构造与成矿学》 EI CAS CSCD 北大核心 2024年第2期368-379,共12页
卡拉塔格是东天山十分重要的铜矿集区,发育5个不同时代和成矿类型的成矿系统。近年来新发现了黄滩(包括金岭)金铜锌矿床,赋存于火山岩系中,发育层状矿化、脉状矿化和黄铁绢英岩化,但层状矿化和黄铁绢英岩化形成时代不清楚,制约了进一步... 卡拉塔格是东天山十分重要的铜矿集区,发育5个不同时代和成矿类型的成矿系统。近年来新发现了黄滩(包括金岭)金铜锌矿床,赋存于火山岩系中,发育层状矿化、脉状矿化和黄铁绢英岩化,但层状矿化和黄铁绢英岩化形成时代不清楚,制约了进一步找矿勘查工作。本文基于野外调查和室内研究,开展白云母^(40)Ar-^(39)Ar年龄和黄铁矿Re-Os年代学研究,获得黄铁绢英岩中白云母^(40)Ar-^(39)Ar坪年龄为429.46±3.91 Ma,7件层状矿化中黄铁矿Re-Os等时线年龄为436.5±4.2 Ma。层状矿化年龄与前人获得含矿岩系英安岩和英安质凝灰岩年龄(434~438 Ma)、脉状矿化年龄(432~438 Ma)一致,表明层状矿化、脉状矿化和黄铁绢英岩化是同一成矿事件的产物,黄滩为富金火山成因块状硫化物(VMS)型矿床。因此,尽管黄滩和红海‒黄土坡为VMS型矿床,红石为火山热液脉状矿床,但它们均为同一VMS成矿系统,形成于430~439 Ma,受控矿因素的差异,造成了成因类型、矿化类型和成矿元素组合的多样性。 展开更多
关键词 白云母^(40)Ar-^(39)Ar年龄 黄铁矿Re-os年龄 VMS矿床 金铜锌 黄滩 东天山
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A measurable refinement method of design and verification for micro-kernel operating systems in communication network 被引量:1
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作者 Zhenjiang Qian Rui Xia +2 位作者 Gaofei Sun Xiaoshuang Xing Kaijian Xia 《Digital Communications and Networks》 SCIE CSCD 2023年第5期1070-1079,共10页
A secure operating system in the communication network can provide the stable working environment,which ensures that the user information is not stolen.The micro-kernel operating system in the communication network re... A secure operating system in the communication network can provide the stable working environment,which ensures that the user information is not stolen.The micro-kernel operating system in the communication network retains the core functions in the kernel,and unnecessary tasks are implemented by calling external processes.Due to the small amount of code,the micro-kernel architecture has high reliability and scalability.Taking the microkernel operating system in the communication network prototype VSOS as an example,we employ the objdump tool to disassemble the system source code and get the assembly layer code.On this basis,we apply the Isabelle/HOL,a formal verification tool,to model the system prototype.By referring to the mathematical model of finite automata and taking the process scheduling module as an example,the security verification based on the assembly language layer is developed.Based on the Hoare logic theory,each assembly statement of the module is verified in turn.The verification results show that the scheduling module of VSOS has good functional security,and also show the feasibility of the refinement framework. 展开更多
关键词 Assembly-level verification Finite automaton Hoare logic Isabelle/HOL Micro-kernel os
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原油组分Re-Os放射性同位素体系特征及其定年机理与应用启示
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作者 刘俊杰 殷启春 +3 位作者 龚赞 李作生 龙晓平 李杰 《大地构造与成矿学》 EI CAS CSCD 北大核心 2024年第3期557-565,共9页
Re-Os放射性同位素体系可用于含油气系统关键地质过程的定年与示踪研究。不过,Re-Os定年的精度仍受到有关科学问题的制约,如原油组分的Re-Os体系特征、沥青质渐进散失对原油Re-Os体系特征与定年应用的影响等。本研究通过二元溶液直接分... Re-Os放射性同位素体系可用于含油气系统关键地质过程的定年与示踪研究。不过,Re-Os定年的精度仍受到有关科学问题的制约,如原油组分的Re-Os体系特征、沥青质渐进散失对原油Re-Os体系特征与定年应用的影响等。本研究通过二元溶液直接分离原油次组分的实验,揭示了原油组分的Re-Os体系特征,模拟了实际地质情况中沥青质渐进散失对原油Re-Os体系特征与定年应用的影响,并通过重复实验验证相关实验流程对所取得的结果和认识的影响。研究发现,根据沉淀的先后顺序,原油次组分的Re和Os元素丰度总体上呈下降趋势,但有起伏变化,Re-Os同位素比值则单调下降。因此,沥青质的渐进散失将导致原油Re和Os元素丰度以及Re-Os同位素比值降低,进而对原油和低成熟度沥青Re-Os定年与示踪的应用产生影响。重复实验表明,实验室分离次组分的操作结果具有一定的随机性,但不影响Re-Os体系的总体性质。 展开更多
关键词 RM8505原油 次组分 Re-os放射性同位素体系 RE-os定年
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长链非编码RNA DNM3OS在癌症中的研究进展
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作者 宁理懂 赵冠焱 周志宇 《医学综述》 CAS 2024年第10期1194-1199,共6页
癌症是人类死亡的最主要原因之一。长链非编码RNA(lncRNA)参与调节多种癌细胞的形成、侵袭以及迁移。其中,lncRNA DNM3OS参与多种癌症的发生发展,如呼吸系统肿瘤、消化系统肿瘤、泌尿生殖系统肿瘤及其他恶性肿瘤。lncRNA DNM3OS在上述... 癌症是人类死亡的最主要原因之一。长链非编码RNA(lncRNA)参与调节多种癌细胞的形成、侵袭以及迁移。其中,lncRNA DNM3OS参与多种癌症的发生发展,如呼吸系统肿瘤、消化系统肿瘤、泌尿生殖系统肿瘤及其他恶性肿瘤。lncRNA DNM3OS在上述癌细胞中差异表达,与癌症患者的预后密切相关。同时,DNM3OS作为lncRNA可以与不同的微RNA结合,通过参与磷脂酰肌醇-3-激酶/蛋白激酶B信号通路、血小板衍生生长因子/血小板衍生生长因子受体信号通路等发挥生物学作用,提示DNM3OS可能成为多种癌症新的潜在诊疗靶点。然而,目前关于lncRNA DNM3OS的功能研究主要集中在细胞水平,在实验动物中的研究报道较少,未来仍需深入研究lncRNA DNM3OS在癌症中的机制。 展开更多
关键词 癌症 长链非编码RNA DNM3os
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Super-Boost变换器的工作模式及输出纹波电压分析
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作者 皇金锋 韩梦祺 《电源学报》 CSCD 北大核心 2024年第1期11-21,共11页
Super-Boost变换器代替传统的充、放电模块可大大减小电源的质量和体积,提高其功率密度,因此在空间电力系统中具有广阔的应用前景。但由于Super-Boost变换器有多个功率元件,且存在电感电流反向流动特性,导致其供能模式及输出纹波电压较... Super-Boost变换器代替传统的充、放电模块可大大减小电源的质量和体积,提高其功率密度,因此在空间电力系统中具有广阔的应用前景。但由于Super-Boost变换器有多个功率元件,且存在电感电流反向流动特性,导致其供能模式及输出纹波电压较传统Boost变换器复杂。为了给Super-Boost变换器的分析和设计提供正确的理论指导,对Super-Boost变换器供能模式及输出纹波电压进行了深入研究。研究发现,电感L_(1)和L_(2)均存在连续导电模式、伪连续导电模式和伪断续导电模式等工作模式,建立各工作模式的临界电感和输出纹波电压解析数学模型,探讨峰值电流与电感间的关系,得到了满足设计要求的最小电容和最小电感,据此给出了变换器参数设计方法,实验结果验证了理论分析的正确性。 展开更多
关键词 Super-Boost变换器 工作模式 临界电感 输出纹波电压 参数设计
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微管抑制及尾桥蛋白磷酸化促进骨肉瘤细胞U2OS微核形成
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作者 阮荻 孙林 +3 位作者 潘高 周文豪 林怡然 龚业莉 《华中科技大学学报(医学版)》 CAS CSCD 北大核心 2024年第2期207-213,共7页
目的探讨微管及微管相关蛋白尾桥蛋白在肿瘤细胞微核形成中的作用。方法利用DAPI染色检测不同类型细胞自发微核率;利用诺考达唑(nocodazole)抑制微管聚集后,DAPI染色和胞质分裂阻滞(cytokinesis-block,CB)微核实验观察人骨肉瘤细胞株U2O... 目的探讨微管及微管相关蛋白尾桥蛋白在肿瘤细胞微核形成中的作用。方法利用DAPI染色检测不同类型细胞自发微核率;利用诺考达唑(nocodazole)抑制微管聚集后,DAPI染色和胞质分裂阻滞(cytokinesis-block,CB)微核实验观察人骨肉瘤细胞株U2OS中微核形成情况;免疫荧光多重染色检测诺考达唑处理不同时间对U2OS细胞中微管及尾桥蛋白的影响;在U2OS细胞中过表达尾桥蛋白或利用collybistin使尾桥蛋白磷酸化,再利用免疫荧光及DAPI染色检测其对微管及微核形成的影响。结果相对于人胚肾HEK293细胞和原代神经细胞,U2OS自发微核率更高;诺考达唑处理使U2OS细胞微核数量增加,且与释放时间相关;诺考达唑处理使尾桥蛋白分布改变,逐渐聚集于细胞核;U2OS细胞中磷酸化尾桥蛋白主要表达于分裂期细胞;过表达尾桥蛋白和(或)增加其磷酸化水平并不影响U2OS细胞中微管蛋白的表达,但过表达尾桥蛋白并增加其磷酸化水平可使微核数量增多。结论肿瘤细胞内微核形成与微管聚集能力关系密切,可形成于细胞周期不同时期,具有积累效应。尾桥蛋白磷酸化后细胞中微核数量增多,提示其可能参与调节肿瘤细胞微核形成。 展开更多
关键词 微管 微核 尾桥蛋白 诺考达唑 collybistin U2os
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Pt-Re-Os同位素体系分析技术研究进展
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作者 鲍厚银 李杰 《地球化学》 CAS CSCD 北大核心 2024年第4期595-610,共16页
Pt-Os和Re-Os同位素体系(统称Pt-Re-Os同位素体系)在壳–幔和核–幔相互作用、矿床成因、陨石成因、太阳系早期演化等地球科学研究中具有重要应用潜力。由于地质样品中Pt-Re-Os含量极低(pg/g~ng/g级),对其元素含量和同位素组成进行高精... Pt-Os和Re-Os同位素体系(统称Pt-Re-Os同位素体系)在壳–幔和核–幔相互作用、矿床成因、陨石成因、太阳系早期演化等地球科学研究中具有重要应用潜力。由于地质样品中Pt-Re-Os含量极低(pg/g~ng/g级),对其元素含量和同位素组成进行高精度的分析测试极具挑战。本文对Pt-Re-Os同位素化学前处理和质谱测定方法研究进展进行综述。化学前处理方法包括酸溶法、碱熔法、火试金法、Carius管溶样法和HPA-S高温高压釜溶样法等常用的样品消解方法以及Pt-Re-Os的化学分离与纯化技术。重点介绍了负离子热电离质谱法(N-TIMS)和(多接收器)电感耦合等离子体质谱法(ICP-MS和MC-ICP-MS)测试Pt-Re-Os元素含量及同位素组成的原理、标准物质和测量精度,以及近年来高精度Os同位素质谱测定中O同位素校正、质量分馏校正、多原子干扰和提高灵敏度等质谱分析技术研究进展。与Re-Os同位素分析技术相比,Pt-Os同位素分析技术还存在困难,国内Pt-Os同位素分析技术仍处于起步阶段。本综述可为Pt-Re-Os同位素分析方法研究提供参考,从而推动国内Pt-Re-Os同位素地球化学研究的发展。 展开更多
关键词 RE-os同位素 Pt-os同位素 消解 化学分离 质谱测量
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Proposing Adjustments to the Dry Season Inter-Reservoir Operation Rules of the Red River System to Improve Water Use Efficiency of the Reservoirs
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作者 Thuy T. B. Nguyen Ninh H. Bui 《Journal of Geoscience and Environment Protection》 2023年第5期316-334,共19页
The Red-Thai Binh River system is an important water resource to the Northern Delta, serving the development of agriculture, people’s livelihood and other economic sectors through its upstream reservoirs and a system... The Red-Thai Binh River system is an important water resource to the Northern Delta, serving the development of agriculture, people’s livelihood and other economic sectors through its upstream reservoirs and a system of water abstraction works along the rivers. However, due to the impact of climate change and pressure from socio-economic development, the operation of the reservoir system according to Decision No. 740/QD-TTg was issued on June 17, 2019 by the Prime Minister of Government promulgating the Red-Thai Binh River system inter-reservoir operation rules (Operation rules 740) has some shortcomings that need adjustments for higher water use efficiency, meeting downstream water demand and power generation benefits. Through the results of water balance calculation and analysis of economic benefits from water use scenarios, this research proposed adjustment to the inter-reservoir operation during dry season in the Red River system. The result showed that an average water level of 1.0 - 1.7 m should be maintained at Hanoi during the increased release period. 展开更多
关键词 Inter-Reservoir Operation Adjustment Operation Rules RESERVOIRS Red-Thai Binh River Basin
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UOS系统常见故障的诊断与排除
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作者 郭旭敏 《山西电子技术》 2024年第4期33-34,111,共3页
国产计算机操作系统越来越广泛地应用于日常工作中,基于Linux的国产计算机操作系统UOS在使用过程中仍存在着较多故障。基于此,把使用UOS系统时常见的故障进行了归纳总结,并对常见的故障给出了解决思路和关键修复步骤,从而帮助UOS系统使... 国产计算机操作系统越来越广泛地应用于日常工作中,基于Linux的国产计算机操作系统UOS在使用过程中仍存在着较多故障。基于此,把使用UOS系统时常见的故障进行了归纳总结,并对常见的故障给出了解决思路和关键修复步骤,从而帮助UOS系统使用者或系统管理员快速定位和修复故障,为保证UOS系统正常使用提供方法和依据。 展开更多
关键词 操作系统 Uos 故障诊断 故障修复
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吉林省敦化市松江河金(钼)矿床辉钼矿Re-Os年龄及其地质意义
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作者 陈诗戈 顾尚义 +3 位作者 陈原林 徐爱军 郑朝阳 杨晓明 《矿物学报》 CAS CSCD 北大核心 2024年第2期242-252,共11页
松江河金(钼)矿是近十年来发现的产在韧性变形带内的一座中型金矿床(Au资源储量达9 t)。近年来,在松江河矿区五中段至八中段发现大量辉钼矿分布,至少延深至九中段,从五中至八中段钼矿化具有明显的增强趋势。为确定钼成矿时代,文章利用... 松江河金(钼)矿是近十年来发现的产在韧性变形带内的一座中型金矿床(Au资源储量达9 t)。近年来,在松江河矿区五中段至八中段发现大量辉钼矿分布,至少延深至九中段,从五中至八中段钼矿化具有明显的增强趋势。为确定钼成矿时代,文章利用高精度ICP-MS辉钼矿Re-Os同位素测年技术,首次获得了松江河矿床的辉钼矿Re-Os同位素加权平均模式年龄和等时线年龄分别为(167±2.4) Ma和(158±10)Ma,该年龄与前人报道的松江河矿区黄泥河岩体的年龄(164~162 Ma)和五道溜河岩体的年龄(174~172 Ma)误差范围内基本一致,证实了该矿床成矿与成岩作用近于同时发生,且主要在燕山早期的中、晚侏罗世。结合吉林省中东部地区已发表的成岩与成矿年代学资料,文章认为,区内钼多金属矿床形成于燕山期古太平洋板块向欧亚大陆岩石圈俯冲的活动大陆边缘的地球动力学背景。矿床中辉钼矿的ω(Re)为142.74×10^(-6)~217.67×10^(-6),均值为196.58×10^(-6),结合矿床地质特征和成矿岩体及矿石O、S、Pb同位素等证据,文章认为该矿床的成矿物质主要为地幔来源,来自深部的流体可能对该矿床的成矿作用起了重要作用。 展开更多
关键词 辉钼矿 Re-os等时线年龄 松江河金(钼)矿床 吉林省中东部
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Similarity matching method of power distribution system operating data based on neural information retrieval
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作者 Kai Xiao Daoxing Li +2 位作者 Pengtian Guo Xiaohui Wang Yong Chen 《Global Energy Interconnection》 EI CAS CSCD 2023年第1期15-25,共11页
Operation control of power systems has become challenging with an increase in the scale and complexity of power distribution systems and extensive access to renewable energy.Therefore,improvement of the ability of dat... Operation control of power systems has become challenging with an increase in the scale and complexity of power distribution systems and extensive access to renewable energy.Therefore,improvement of the ability of data-driven operation management,intelligent analysis,and mining is urgently required.To investigate and explore similar regularities of the historical operating section of the power distribution system and assist the power grid in obtaining high-value historical operation,maintenance experience,and knowledge by rule and line,a neural information retrieval model with an attention mechanism is proposed based on graph data computing technology.Based on the processing flow of the operating data of the power distribution system,a technical framework of neural information retrieval is established.Combined with the natural graph characteristics of the power distribution system,a unified graph data structure and a data fusion method of data access,data complement,and multi-source data are constructed.Further,a graph node feature-embedding representation learning algorithm and a neural information retrieval algorithm model are constructed.The neural information retrieval algorithm model is trained and tested using the generated graph node feature representation vector set.The model is verified on the operating section of the power distribution system of a provincial grid area.The results show that the proposed method demonstrates high accuracy in the similarity matching of historical operation characteristics and effectively supports intelligent fault diagnosis and elimination in power distribution systems. 展开更多
关键词 Neural information retrieval Power distribution Graph data operating section Similarity matching
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赣北石门寺钨铜多金属矿床辉钼矿Re-Os同位素年龄及其地质意义
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作者 刘更更 吴颖宸 +2 位作者 魏文凤 严冰 邹志超 《矿物岩石地球化学通报》 CAS CSCD 北大核心 2024年第1期192-210,共19页
为了解赣北石门寺钨铜多金属矿床的钨富集机理及矿床成因,对该矿床中的辉钼矿开展了Re-Os同位素年代学研究。结果显示,6件辉钼矿样品的Re-Os模式年龄为140.2~142.5 Ma,加权平均年龄为(141.37±0.84)Ma(MSWD=0.84),等时线年龄为(141.... 为了解赣北石门寺钨铜多金属矿床的钨富集机理及矿床成因,对该矿床中的辉钼矿开展了Re-Os同位素年代学研究。结果显示,6件辉钼矿样品的Re-Os模式年龄为140.2~142.5 Ma,加权平均年龄为(141.37±0.84)Ma(MSWD=0.84),等时线年龄为(141.79±0.97)Ma(MSWD=1.10),二者在误差范围内一致,可以代表辉钼矿的矿化年龄,指示该矿床的成矿时间为141 Ma左右。对赣北、赣中和赣南地区的成岩成矿年龄进行对比,发现三地的成岩成矿事件在时间上具有连续性。结合区域构造演化历程,本文认为石门寺钨铜多金属矿形成于早白垩世时期的伸展减薄环境。 展开更多
关键词 石门寺钨铜多金属矿床 RE-os同位素 成矿年龄 赣北、赣中和赣南
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