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不含3-圈和4-圈的IC-平面图的均匀染色问题
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作者 黄丹君 吴弦禧 《浙江师范大学学报(自然科学版)》 2026年第1期26-32,共7页
图G的均匀k-染色是图G的一个正常k-点染色,且满足对任意i,j∈{1,2,…,k},有||V_(i)|-|V_(j)||≤1,其中V_(i)(1≤i≤k)表示染颜色i的顶点集.基于已有的研究结果,研究了不含3-圈和4-圈的IC-平面图,运用反证法证明得到了:Δ(G)≥7且不含3-... 图G的均匀k-染色是图G的一个正常k-点染色,且满足对任意i,j∈{1,2,…,k},有||V_(i)|-|V_(j)||≤1,其中V_(i)(1≤i≤k)表示染颜色i的顶点集.基于已有的研究结果,研究了不含3-圈和4-圈的IC-平面图,运用反证法证明得到了:Δ(G)≥7且不含3-圈和4-圈的IC-平面图是均匀Δ(G)-可染的,其中Δ(G)是图G的最大度. 展开更多
关键词 均匀染色 ic-平面图 最大度
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Towards Net Zero Resilience: A Futuristic Architectural Strategy for Cyber-Attack Defence in Industrial Control Systems (ICS) and Operational Technology (OT) 被引量:1
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作者 Hariharan Ramachandran Richard Smith +2 位作者 Kenny Awuson David Tawfik Al-Hadhrami Parag Acharya 《Computers, Materials & Continua》 2025年第2期3619-3641,共23页
This paper introduces the Integrated Security Embedded Resilience Architecture (ISERA) as an advanced resilience mechanism for Industrial Control Systems (ICS) and Operational Technology (OT) environments. The ISERA f... This paper introduces the Integrated Security Embedded Resilience Architecture (ISERA) as an advanced resilience mechanism for Industrial Control Systems (ICS) and Operational Technology (OT) environments. The ISERA framework integrates security by design principles, micro-segmentation, and Island Mode Operation (IMO) to enhance cyber resilience and ensure continuous, secure operations. The methodology deploys a Forward-Thinking Architecture Strategy (FTAS) algorithm, which utilises an industrial Intrusion Detection System (IDS) implemented with Python’s Network Intrusion Detection System (NIDS) library. The FTAS algorithm successfully identified and responded to cyber-attacks, ensuring minimal system disruption. ISERA has been validated through comprehensive testing scenarios simulating Denial of Service (DoS) attacks and malware intrusions, at both the IT and OT layers where it successfully mitigates the impact of malicious activity. Results demonstrate ISERA’s efficacy in real-time threat detection, containment, and incident response, thus ensuring the integrity and reliability of critical infrastructure systems. ISERA’s decentralised approach contributes to global net zero goals by optimising resource use and minimising environmental impact. By adopting a decentralised control architecture and leveraging virtualisation, ISERA significantly enhances the cyber resilience and sustainability of critical infrastructure systems. This approach not only strengthens defences against evolving cyber threats but also optimises resource allocation, reducing the system’s carbon footprint. As a result, ISERA ensures the uninterrupted operation of essential services while contributing to broader net zero goals. 展开更多
关键词 icS/OT cyber Programmable Logic Controllers(PLC)security detection safety reliability proof testing gas compressor station icS resilience security architecture icS
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An Electro⁃thermal De⁃icing Model and Simulation Analysis Considering Ice Shedding
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作者 ZHANG Yingying YUAN Xiansheng +1 位作者 XIONG Jingjiang BU Xueqin 《Transactions of Nanjing University of Aeronautics and Astronautics》 2025年第2期162-177,共16页
The electro⁃thermal anti/de-icing systems have high heating efficiency and relatively simple structures,marking them as a key development direction for future icing protection.Existing simulation algorithms for electr... The electro⁃thermal anti/de-icing systems have high heating efficiency and relatively simple structures,marking them as a key development direction for future icing protection.Existing simulation algorithms for electrothermal de-icing seldom delve into comprehensive ice accretion-melting-deicing models that account for ice shedding.Therefore,the detachment behavior of ice layers during the heating process requires in-depth research and discussion.This paper physically models the phenomenon of ice shedding,incorporates the detachment behavior of ice layers during heating,improves the existing mathematical model for electro-thermal de-icing calculations,establishes an ice accretion-melting-deicing model for electro-thermal de-icing systems,and conducts numerical simulation,verification and optimization analysis of electro-thermal de-icing considering ice shedding.Through multi-condition de-icing numerical simulations of a specific wing model,it is found that ambient temperature can serve as a factor for adapting the electro heating anti/de-icing strategy to the environment.An optimization of heating heat flux density and heating/cooling time is conducted for the wing de-icing control law under the calculated conditions.The improved electrothermal de-icing model and algorithm developed in this paper provide solid technical support for the design of electrothermal de-icing systems. 展开更多
关键词 aircraft icing electro-thermal de-icing ice shedding electro-thermal control law numerical simulation
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The ICS international chronostratigraphic chart this decade
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作者 Kim Cohen David Harper +1 位作者 Philip Gibbard Nicholas Car 《Episodes》 2025年第1期105-115,共11页
The International Commission on Stratigraphy(ICS)has been producing and updating its International Chro-nostratigraphic Chart for several decades.The chart communicates higher-order divisions of geological time and ac... The International Commission on Stratigraphy(ICS)has been producing and updating its International Chro-nostratigraphic Chart for several decades.The chart communicates higher-order divisions of geological time and actual knowledge on the numerical ages of their bound-aries.Distributed via the ICS website www.stratigraphy.org the chart promotes use in graphic,tabulated and further digital forms in multiple languages.This paper is a status update,eleven years since the last such publication,cov-ering activities between 2012 and 2024.Chart updates during the past decade have echoed the ICS’s primary objective of precisely defining a global standard set of time-correlative units(Systems,Series,Stages)for stratigraphic successions worldwide.These units are,in turn,the basis for the Periods,Epochs,and Ages of the Geological Time Scale.Their standardization is fundamental for expressing geological knowledge,in application and education,out-reach and continuing research.The chart offers a frame-work through which regional-scale higher-resolution divisions can be linked,equated and collated.Likewise it offers a framework for digital representation of the Geological Time Scale.Maintenance and distribution of chart versions on the web has been a manual endeavour,a process that ICS is upgrading to serve an increasingly digital world. 展开更多
关键词 digital representation geological knowledge education standard time correlative units commission stratigraphy ics chronostratigraphic chart geological time scale international commission stratigraphy
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集成电路反向工程中HE-UNet的IC图像分割算法研究
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作者 程弘楠 张晨光 《计算机工程》 北大核心 2026年第1期196-205,共10页
芯片产业是国家安全和经济发展的重要基础,而集成电路(IC)反向工程(RE)作为分析芯片内部性能的手段,是芯片产业链中的重要环节。RE包括从扫描电子显微镜(SEM)逐层采集芯片图像、识别器件、提取栅极网表、推断其功能等步骤,而将电气元件... 芯片产业是国家安全和经济发展的重要基础,而集成电路(IC)反向工程(RE)作为分析芯片内部性能的手段,是芯片产业链中的重要环节。RE包括从扫描电子显微镜(SEM)逐层采集芯片图像、识别器件、提取栅极网表、推断其功能等步骤,而将电气元件和金属线从IC图像背景中分割出来是识别器件等步骤的前提。然而,传统图像分割方法因为缺乏专家经验的学习,不能适应IC图像复杂多变的电路情况。为此,提出一种HE-UNet方法,用于提取IC图像中的金属线与过孔。HE-UNet包含3个步骤:首先,利用U-M2网络提取芯片图像的含噪特征;其次,利用霍夫圆检测算法去除过孔周围的噪声;最后,利用边缘检测池化去除远离过孔的噪声。在尺寸为1024×1024像素的IC图像上进行实验,结果表明,HE-UNet可以有效完成金属线和过孔的分割,其平均交并比(mIoU)为98.24%,平均像素准确率(MPA)为99.11%,均优于对比方法。 展开更多
关键词 集成电路 反向工程 图像分割 霍夫圆检测 HE-UNet
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Insular cortex sends excitatory projections to GABAergic neurons in the nucleus tractus solitarii in rats
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作者 CHEN Yingbiao SHI Zhen +3 位作者 YIN Junbin BAI Yang FAN Qitong LI Yunqing 《神经解剖学杂志》 北大核心 2025年第4期411-421,共11页
Objective:To anatomically and phenotypically characterize the insular cortex(IC)-nucleus tractus soli-tari(NTS)neural pathway.Methods:Adult male Sprague-Dawley rats were divided into three experimental cohorts for neu... Objective:To anatomically and phenotypically characterize the insular cortex(IC)-nucleus tractus soli-tari(NTS)neural pathway.Methods:Adult male Sprague-Dawley rats were divided into three experimental cohorts for neural circuit tracing.Anterograde labeling was achieved by injecting anterograde self-complementary adeno-associated viruses(scAAVs)into the IC.Retrograde tracing involved NTS injections of either retrograde scAAVs or FluoroGold(FG),combined with immunofluorescence histochemical staining to identify IC-originating projection neurons.For postsynaptic neurochemical phenotype characterization,IC was injected with AAV2/1-CaMKII-Cre,while a mixture of AAV2/9-Syn-DIO-mCherry and AAV2/9-VGAT1-EGFP was injected into the NTS.The rats were allowed to survive for one week following scAAVs or FG injection or four weeks after recombinase-dependent systems injection.Then the rats were sacrificed,and serial brain sections were prepared for immunofluorescence histochemical staining(brain section containing FG)and subsequent fluorescence/confocal microscopic analysis.Results:(1)Anterograde viral tracing re-vealed dense axonal terminals from the IC projecting to the medial subnucleus of the NTS,while retrograde tracing re-vealed that IC neurons projecting to the NTS were predominantly localized within the dysgranular layer;(2)IC-NTS projection neurons were exclusive glutamatergic(100%,n=3);(3)NTS neurons receiving IC inputs were mainly lo-calized in the medial subnucleus,and were predominantly GABAergic(79.8±3.2%,n=3).Conclusion:The pres-ent results indicate that a descending pathway from excitatory neurons of the IC terminates onto inhibitory neurons of the NTS,which might represent a potential neuromodulatory target for visceral pain disorders. 展开更多
关键词 nucleus tractus solitari(NTS) insular cortex(ic) anterograde transmonosynaptsis glutamatergic neurons GABAergic neurons RAT
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Improved Geochronologic Accuracy and Precision for the ICS Chronostratigraphic Charts:Examples from the late Cambrian-Early Ordovician
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作者 E.Landing A.W.A.Rushton +1 位作者 R.A.Fortey S.A.Bowring 《Episodes》 2015年第3期154-161,共8页
The utility of ICS International Chronostratigraphic Charts(ICS Charts)relies on the accuracy and precision of reported geochronologic dates and their relationship to the bases of global chronostratigraphic units.Howe... The utility of ICS International Chronostratigraphic Charts(ICS Charts)relies on the accuracy and precision of reported geochronologic dates and their relationship to the bases of global chronostratigraphic units.However,an examination of some early Paleozoic dates(i.e.,Cambrian-Ordovician boundary and lowest Ordovician)on the ICS Charts shows that they differ from originally reported and late recalculated dates.Thus,they record a numerical precision that differs from these revised dates.The dates assigned to the bases of formal early Paleozoic chronostratigraphic units may be interpreted by the lay reader as precise determinations. 展开更多
关键词 ics charts ics chronostratigraphic charts ics international chronostratigraphic charts ics charts relies early paleozoic dates iecambrian ordovician geochronologic dates PRECISION record numerical precision late cambrian early ordovician
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Icing Characteristics and Anti⁃icing Research of Supercooled Large Droplet Impact on Epoxy Composite Surfaces
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作者 LI Xiaofei WANG Xiangzhao +2 位作者 JI Zemin HUANG Xiaobin LIU Hong 《Transactions of Nanjing University of Aeronautics and Astronautics》 2025年第2期178-190,共13页
The icing characteristics of supercooled large droplet(SLD)impacting carbon fiber-reinforced composites(CFRCs)remain poorly understood,hindering the enhancement of ice protection capabilities and the certification of ... The icing characteristics of supercooled large droplet(SLD)impacting carbon fiber-reinforced composites(CFRCs)remain poorly understood,hindering the enhancement of ice protection capabilities and the certification of ice-accreted composite aircraft.The paper systematically investigates the effects of the supercooling degree,the surface temperature,and the impact velocity on the ice accretion behavior of SLDs impacting carbon fiber-reinforced epoxy composite surfaces.To address the ice-prone nature of CFRCs,nanoparticle-modified anti-icing coatings are developed,and the icing characteristics of SLD-impacted modified carbon fiber-reinforced epoxy composite surfaces are analyzed.Results demonstrate that surface-modified carbon fiber-reinforced epoxy composite exhibits significantly delayed ice formation.Under conditions of droplet temperature(−15℃)and surface temperature(−18℃),the icing time of hydrophobic-modified CFRCs was delayed by over 1100 ms,representing a 5.4-fold improvement compared to the unmodified carbon fiber-reinforced epoxy composite. 展开更多
关键词 aircraft icing carbon fiber-reinforced epoxy composites supercooled large droplets hydrophobic modification icing protection
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Impingement Characteristics Investigation of Supercooled Large Droplets Based on Eulerian Method
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作者 YE Zekun SHEN Xiaobin +1 位作者 ZHAO Jingyu LIN Guiping 《Transactions of Nanjing University of Aeronautics and Astronautics》 2025年第2期191-200,共10页
This numerical simulation investigates the two⁃phase flow under the condition of supercooled large droplets impinging on the aircraft surface.Based on Eulerian framework,a method for calculating supercooled water drop... This numerical simulation investigates the two⁃phase flow under the condition of supercooled large droplets impinging on the aircraft surface.Based on Eulerian framework,a method for calculating supercooled water droplet impingement characteristics is established.Then,considering the deformation and breaking effects during the movement,this method is extended to calculate the impingement characteristics of supercooled large droplets,as well as the bouncing and splashing effects during impingement.The impingement characteristics of supercooled large droplets is then investigated by this method.The results demonstrate that the deformation and breaking effects of supercooled large droplets have negligible influence on the impingement characteristics under the experimental conditions of this paper.In addition,the results of the impingement range and collection efficiency decrease when considering the bouncing and splashing effects.The bouncing effect mainly affects the mass loss near the impingement limits,while the splashing effect influences the result around the stagnation point.This investigation is beneficial for the analysis of aircraft icing and the design of anti⁃icing system with supercooled large droplet conditions. 展开更多
关键词 aircraft icing droplet impingement characteristics supercooled large droplet(SLD) Eulerian method numerical simulation
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Droplet Collection Efficiency Analysis in the Event of Wind Turbine Blades Glaze Ice Formation Based on Euler Wall Film Model
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作者 WU Dao-lei BAI Xu DU Yue 《China Ocean Engineering》 2025年第4期621-634,共14页
Wind turbine blades in cold regions are susceptible to icing due to meteorological conditions,significantly affecting the turbine's energy capture efficiency and operational safety.Precise calculation of droplet c... Wind turbine blades in cold regions are susceptible to icing due to meteorological conditions,significantly affecting the turbine's energy capture efficiency and operational safety.Precise calculation of droplet collection efficiency(DCE)is essential for accurate icing prediction.This study examines existing methods for calculating DCE and identifies limitations during glaze ice formation.An enhanced method based on the Euler Wall Film(EWF)model is introduced to address these limitations,incorporating splashing and rebound phenomena during glaze ice formation on wind turbine blades.The method's reliability is validated using data from the classic symmetric airfoil,NACA0012.Through the control variable method,this research examines DCE variations under different incoming velocities,medium volume droplet diameters(MVDs),and temperatures.The study also analyzes the distinctions between the improved method and the existing Eulerian method.Results indicate that both impact range and maximum DCE increase with higher incoming velocity and MVD,while temperature exhibits minimal influence on DCE.Variations between the calculation methods reveal differences in water droplet splashing intensity,primarily influenced by droplet kinetic energy and liquid film thickness.The splashing phenomenon gradually decreases as incoming velocity and MVD increase. 展开更多
关键词 Droplet Collection Efficiency(DCE) Euler Wall Film(EWF) blade icing glaze ice wind turbine
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A data-driven methodology to predict ice-induced aerodynamic degradation applied to aircraft tailplane design
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作者 Salvatore CORCIONE Agostino DE MARCO Vincenzo CUSATI 《Chinese Journal of Aeronautics》 2025年第8期328-346,共19页
This study presents a data-driven approach to predict tailplane aerodynamics in icing conditions,supporting the ice-tolerant design of aircraft horizontal stabilizers.The core of this work is a low-cost predictive mod... This study presents a data-driven approach to predict tailplane aerodynamics in icing conditions,supporting the ice-tolerant design of aircraft horizontal stabilizers.The core of this work is a low-cost predictive model for analyzing icing effects on swept tailplanes.The method relies on a multi-fidelity data gathering campaign,enabling seamless integration into multidisciplinary aircraft design workflows.A dataset of iced airfoil shapes was generated using 2D inviscid methods across various flight conditions.High-fidelity CFD simulations were conducted on both clean and iced geometries,forming a multidimensional aerodynamic database.This 2D database feeds a nonlinear vortex lattice method to estimate 3D aerodynamic characteristics,following a'quasi-3D'approach.The resulting reduced-order model delivers fast aerodynamic performance estimates of iced tailplanes.To demonstrate its effectiveness,optimal ice-tolerant tailplane designs were selected from a range of feasible shapes based on a reference transport aircraft.The analysis validates the model's reliability,accuracy,and limitations concerning 3D ice shapes and aerodynamic characteristics.Most notably,the model offers near-zero computational cost compared to high-fidelity simulations,making it a valuable tool for efficient aircraft design. 展开更多
关键词 Data-driven aerodynamics Forward swept tailplane Gaussian process regression ice accretion prediction Machine learning for icing analysis
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Seismic Tremors and Their Relation to Cryosphere Dynamics in April 2015 around the Lützow-Holm Bay, East Antarctica 被引量:1
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作者 Masaki Kanao Takahiko Murayama +1 位作者 Masa-Yuki Yamamoto Yoshiaki Ishihara 《International Journal of Geosciences》 2017年第8期1025-1047,共23页
Characteristics and statistics of seismic tremors occurring during April 2015 were investigated by using short-period and broadband seismographs deployed at Syowa Station (SYO), in the Lützow-Holm Bay (LHB), East... Characteristics and statistics of seismic tremors occurring during April 2015 were investigated by using short-period and broadband seismographs deployed at Syowa Station (SYO), in the Lützow-Holm Bay (LHB), East Antarctica. In order to examine a relationship between surface environments in particular cryosphere variation, the MODIS satellite images were utilized for comparison with the detected tremor events. Since a large volume of sea-ice was discharged during the April, together with several large icebergs passed through from the west to the east at northern edge of the fast sea-ice of LHB, it was expected to detect seismic tremors involving cryospehre dynamics. During the month, a total number of 49 tremor events including short duration ice shocks were identified. Majority of the events (N = 39) had their duration times more than 15 minutes, which were divided into both tremors and ice shocks on the basis of experienced definition at SYO. Cryospheric sources recorded by seismic tremors were classified into several origins (collision, calving, crevassing, crashing, etc.): “crevassing events” along the large cracks inside the fast sea-ice in LHB (04 April), “discharge events” of fast sea-ice from the Bay (07 April), “collision events” between iceberg and the edge of fast sea-ice (14 April), “crashing movement” between fragmentation of fast sea-ice and packed sea-ice (18 April), and other origins. In particular, strong amplitude tremors with harmonic overtones were assumed to be occurred independently from whether condition, because these overtone tremors were identified at less stormy days by comparison with infrasound data at SYO. 展开更多
关键词 SEISMic Tremors ice Shocks CRYOSPHERE DYNAMicS SEA-icE icEBERGS Lützow-Holm BAY Antarctica
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Insufficiency of Cellular Energy (ICE) May Precede Neurodegeneration in Alzheimer’s Disease and Be Treatable via the Alternative Cellular Energy (ACE) Pathway 被引量:2
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作者 W. John Martin 《Advances in Alzheimer's Disease》 2017年第1期1-12,共12页
The term neurodegeneration emphasizes the destruction of neuronal cells as the primary explanation of many major neurological illnesses, including Alzheimer’s disease. Specialized functioning of cells requires more c... The term neurodegeneration emphasizes the destruction of neuronal cells as the primary explanation of many major neurological illnesses, including Alzheimer’s disease. Specialized functioning of cells requires more cellular energy than is needed for basic cell survival. Cells can acquire energy both from the metabolism of food and from the alternative cellular energy (ACE) pathway. The ACE pathway is an added dynamic (kinetic) quality of the body’s fluids occurring from the absorption of an external force termed KELEA (Kinetic Energy Limiting Electrostatic Attraction). KELEA is attracted to separated electrical charges and is seemingly partially released as the charges become more closely linked. As suggested elsewhere, the fluctuating electrical activity in the brain may attract KELEA from the environment and, thereby, contribute to the body’s ACE pathway. Certain illnesses affecting the brain may impede this proposed antenna function of the brain, leading to a systemic insufficiency of cellular energy (ICE). Furthermore, individual neurons may derive some of the energy for their own activities from the repetitive depolarization of the cell. This may explain why hyper-excitability of neurons can occur in response to cell damage. This adaptive mechanism is unlikely to be sustainable, however, especially if there is a continuing need to synthesize neurotransmitters and membrane ion channels. The energy deficient neurons would then become quiescent and, although remaining viable, would not perform their intended specialized functions. Actual cell death would not necessarily occur till much later in the disease process. The distinction between quiescent and degenerated cells is important since the ACE pathway can be enhanced by several means, including the regular consumption of KELEA activated water. This, in turn, may improve the proposed antenna function of individual neurons, leading to a sustained restoration of specialized function via the ACE pathway. This paper explores this novel concept and provides a rationale for clinical testing of KELEA activated water in patients with neurological and psychiatric illnesses, including Alzheimer’s disease. 展开更多
关键词 Alzheimer’s Disease Alternative CELLULAR ENERGY ACE INSUFFicIENCY of CELLULAR ENERGY icE Kinetic ENERGY Limiting Electrostatic Attraction KELEA Homeopathy Enercel Enerceutical Calorie Metabolism Electrical Charge Membrane Potential NEURODEGENERATION Psychiatry
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茶树ICE基因家族鉴定及CsICE43克隆和低温表达分析
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作者 朱倩 邵陈禹 +3 位作者 周彪 刘硕谦 刘仲华 田娜 《茶叶科学》 北大核心 2025年第1期43-60,共18页
近年来全球极端低温天气频发,严重影响了茶树的产量和品质。ICE(Inducer of CBF expression)基因家族主要参与植物的低温胁迫响应,但在茶树领域中的相关研究还不够全面。本研究从茶树基因组中鉴定出51个茶树CsICEs基因,对其理化性质、... 近年来全球极端低温天气频发,严重影响了茶树的产量和品质。ICE(Inducer of CBF expression)基因家族主要参与植物的低温胁迫响应,但在茶树领域中的相关研究还不够全面。本研究从茶树基因组中鉴定出51个茶树CsICEs基因,对其理化性质、基因结构和启动子顺式作用元件展开生物信息学分析。茶树CsICEs基因的启动子区域富含光响应、植物激素、生长发育及非生物胁迫相关顺式作用元件,其可能参与多种逆境胁迫响应。转录组分析和RT-qPCR验证结果发现,低温下CsICE43基因的表达量上升了4.24倍,其可能与茶树低温响应相关。以茶树品种‘保靖黄金茶1号’的cDNA为模板,克隆获得了CsICE43基因,其在不同组织中的表达模式存在差异,在顶芽和嫩叶中特异性高表达。蛋白氨基酸序列和系统进化树分析表明,CsICE43基因包含与ICE家族其他成员一致的S-rich、bHLH、ACT等保守结构域,且与毛花猕猴桃(Actinidiaeriantha)的亲缘关系较近。在STRING在线网站中以拟南芥AtICEs为模型,推测茶树CsICE43蛋白与HOS1、MYB15、DREB1/2存在潜在的互作关系。亚细胞定位试验表明CsICE43定位于细胞核,与跨膜结构分析结果一致。综上所述,本研究发现CsICE43基因可能与茶树低温响应关联,为深入挖掘其基因功能与抗寒分子机理提供了一定的理论基础。 展开更多
关键词 茶树 icE基因家族 抗寒 生物信息学 表达分析
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Linkages between Arctic sea ice cover,large-scale atmospheric circulation,and weather and ice conditions in the Gulf of Bothnia,Baltic Sea
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作者 Timo Vihma Bin Cheng +2 位作者 Petteri Uotila WEI Lixin QIN Ting 《Advances in Polar Science》 2014年第4期289-299,共11页
During years 1980/1981-2012/2013, inter-annual variations in sea ice and snow thickness in Kemi, in the northern coast of the Gulf of Bothnia, Baltic Sea, depended on the air temperature, snow fall, and rain. Inter-an... During years 1980/1981-2012/2013, inter-annual variations in sea ice and snow thickness in Kemi, in the northern coast of the Gulf of Bothnia, Baltic Sea, depended on the air temperature, snow fall, and rain. Inter-annual variations in the November--April mean air temperature, accumulated total precipitation, snow fall, and rain, as well as ice and snow thickness in Kemi and ice concentration in the Gulf of Bothnia correlated with inter-annual variations of the Pacific Decadal Oscillation (PDO), Arctic Oscillation (AO), North Atlantic Oscillation (NAO), Scandinavian Pattern (SCA), and Polar / Eurasian Pattern (PEU). The strong role of PDO is a new finding. In general, the relationships with PDO were approximately equally strong as those with AO, but rain and sea ice concentration were better correlated with PDO. The correlations with PDO were, however, not persistent; for a study period since 1950 the correlations were much lower. During 1980/1981--2012/2013, also the Pacific / North American Pattern (PNA) and E1 Nino-Southern Oscillation (ENSO) had statistical connections with the conditions in the Gulf of Bothnia, revealed by analyzing their effects combined with those of PDO and AO. A reduced autumn sea ice area in the Arctic was related to increased rain and total precipitation in the following winter in Kemi. This correlation was significant for the Pan-Arctic sea ice area in September, October, and November, and for the November sea ice area in the Barents / Kara seas. 展开更多
关键词 ARCTic Arctic Oscillation Baltic Sea North Atlantic Oscillation Pacific Decadal Oscillation precipitation sea ice SNOW
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Macro-and Microphysical Characteristics of Freezing Rain and Their Impacts on Wire Icing Mechanisms in the Southwestern Mountainous Areas of China 被引量:1
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作者 Yue ZHOU Chunsong LU +3 位作者 Jingjing Lü Xiaoyun SUN Lingli ZHOU Hui XIAO 《Advances in Atmospheric Sciences》 2025年第8期1620-1635,共16页
Based on comprehensive observations of 20 wire icing events during winter from 2019 to 2021,we investigated the characteristics of the icing properties,the atmospheric boundary layer structure,the raindrop size distri... Based on comprehensive observations of 20 wire icing events during winter from 2019 to 2021,we investigated the characteristics of the icing properties,the atmospheric boundary layer structure,the raindrop size distribution,and their associated effects on the ice accretion mechanism in the mountainous region of Southwest China.The maximum ice weight was positively correlated with the duration of ice accretion in the mountainous area.The duration of precipitation accounted for less than 20%of the icing period in the mountainous area,with solid-phase hydrometeors being predominant.Icing events,dominated by freezing rain(FR)and mixed rain–graupel(more than 70%),were characterized by glaze or highdensity mixed icing.The relationship between the melting energy and refreezing energy reflected the distribution characteristics of the proportion of FR under mixed-phase precipitation.The intensity of the warm layer and the dominant precipitation phase significantly affected the variations in the microphysical properties of FR.The melting of large dry snowflakes significantly contributed to FR in the mountainous areas,resulting in smaller generalized intercepts and larger mass-weighted mean diameters in the presence of a stronger warm layer.Under a weaker warm layer,the value of the massweighted mean diameter was significantly smaller because of the inability of large solid particles to melt.Finally,FR in the mountainous area dominated the ice weight during the rapid ice accumulation period.A numerical simulation of FR icing on wires effectively revealed the evolution of disaster-causing icing in mountainous areas. 展开更多
关键词 freezing rain wire icing macro-and microphysical characteristics mountainous area
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LA-MC-ICP-MS微区原位Pb同位素的分析精度研究:以两种类型检测器为例
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作者 余红霞 张银慧 +2 位作者 刘希军 吴玲玲 洪路兵 《地球化学》 北大核心 2025年第1期114-125,共12页
根据样品的Pb含量,本研究建立了法拉第杯-离子计数器(FC-IC)和全法拉第杯(FC)两种杯结构模式微区原位分析Pb同位素比值的方法。因^(206)Pb、^(207)Pb和^(208)Pb在两种模式中均采用FC检测器分析,两种模式下^(20y)Pb/^(206)Pb(y=7、8)值... 根据样品的Pb含量,本研究建立了法拉第杯-离子计数器(FC-IC)和全法拉第杯(FC)两种杯结构模式微区原位分析Pb同位素比值的方法。因^(206)Pb、^(207)Pb和^(208)Pb在两种模式中均采用FC检测器分析,两种模式下^(20y)Pb/^(206)Pb(y=7、8)值的相对标准误差(2RSE)一致,仅与信号强度有关。同等信号强度下(IC线性范围内),^(20x)Pb/^(204)Pb(x=6、7、8)值的2RSE在FC-IC杯结构模式优于FC杯结构模式,且两种模式下^(20x)Pb/^(204)Pb值的2RSE差异随^(208)Pb信号强度的增加而减少,最终均趋于约0.06%。FC-IC杯结构模式分析在^(208)Pb信号强度为0.10~0.25 V时,或FC杯结构模式分析在^(208)Pb信号强度>0.50 V时,均可获得较好的Pb同位素比值的精度和准确度。对于Pb含量较高(>40μg/g)或者尺寸较大的样品,优先采用激光大束斑结合FC杯结构模式可获得高精度的Pb同位素比值;对于Pb含量较低(≈10μg/g)或者尺寸有限的样品,FC-IC杯结构模式获得的Pb同位素精度优于FC杯结构模式。利用建立的微区原位Pb同位素分析方法,本研究分析了不同Pb含量标样的Pb同位素组成,分析结果在误差范围内均与参考值一致。 展开更多
关键词 LA-MC-icP-MS PB含量 原位Pb同位素分析 地质标准样品 法拉第型检测器-离子计数型检测器(FC-ic) 法拉第型检测器(FC)
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Interaction between sea ice/iceberg and ship structures: A review 被引量:4
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作者 JI Shunying LIU Shewen 《Advances in Polar Science》 2012年第4期187-195,共9页
For ship structural design and good maneuverability in an ice-covered sea, the local and global load of ice cover on ships should be well understood. This paper reviews the extensive work done on ice loads on ships, i... For ship structural design and good maneuverability in an ice-covered sea, the local and global load of ice cover on ships should be well understood. This paper reviews the extensive work done on ice loads on ships, including: (a) Ice pressure and local load determination based on field and model tests; (b) Global ice loads on ships from full-scale field observations, model tests and numerical models under different ice conditions (level ice and pack ice) and ship operations (maneuvering and mooring). Spe- cial attention is paid to the discrete element simulation of global ice loads on ships; and (c) Analytical solutions and numerical models of impact loads of icebergs on ships for polar navigation. Finally, research potential in these areas is discussed. 展开更多
关键词 sea ice icEBERG local ice load global ice load ship hull EXPERIMENT numerical simulation
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Historical Course Follows Climate Change: Patterns of the Northern Hemisphere — From Peoples’ Migration until the Industrial Revolution (3<sup>rd</sup>-18<sup>th</sup>Century)
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作者 Werner Schneider Elias Salameh 《Open Journal of Geology》 2018年第13期1167-1194,共28页
This paper relates to the statement that the so-called “Little Ice Age” (RCC 6: 1.350-1.800 A.D.) represents—besides the 8k-Event (8.200-8.000 yr cal. B.P.)—the fastest and strongest onset in Holocene History [1].... This paper relates to the statement that the so-called “Little Ice Age” (RCC 6: 1.350-1.800 A.D.) represents—besides the 8k-Event (8.200-8.000 yr cal. B.P.)—the fastest and strongest onset in Holocene History [1]. Its intention focuses on the correlation of interplaying natural processes (i.e. solar energy variation, aerosols, oceanic currents, volcanism as part of plate tectonics, heat flow) with social/political evidence through the time-span of Peoples’ Migration until Industrial Revolution (3rd-18th Century). The time-span comprises the cool/wet/respectively dry climate phase of the P.M. (260-550), a Climate Optimum (600-1.100 A.D.) owning a final Thermal Maximum (1.100-1.260 A.D.) and the “little Ice Age” (1.350-1.800 A.D.), the latter intercalated by the Sp&#246;rer Minimum (1.460-1.550 A.D.) and the Maunder Minimum (1.650-1.720 A.D.). Thereby, an average temperature difference of 1.0&#176;C - 2.0&#176;C seems sufficient for incising climatic/cultural consequences [2]. It has become obvious that a Climate Optimum primarily provides constructive life conditions;however with a problematic final as the following “Effect-Chain” tells: balanced agricultural/cultural population growth → rich harvests → satisfying nourishment → health, encouragement → overpopulation under favorable materialistic conditions → increasing stress → lack of food, high prices → revolts → migration. In contrast, cool/wet/resp. dry conditions originate destructive/depressive conditions (see Peoples’ Migration) which initiate the following “Effect Chain”: bad agricultural conditions → poor/no harvesting → famine → disease, growing death rate → social, political revolts, wars → human cruelties with psychic/religious background (inquisition, witch-combustion → general chaos (30 yr-war) → death, migration (maritime endeavors, colonization). Furthermore, it should be stressed that volcanic aerosols play besides the solar influx variation—an important role on climate/cultural change [3]. However, the effects of oceanic currents’ heat flow of Mid-Oceanic Ridges and Hot Spots, as well as Earth-Magnetism and Sun/Earth Geometry are poorly understood in this context (Example: Iceland as hot spot situated on the Mid-Atlantic Ridge having been working since 40 Ma). The Chapter-introducing citations play a challenging role in regard to Science Criticism and touch the so-called 95% Confidence line (accepted realm of causal interrelation and according recommendation to Society [4]). 展开更多
关键词 Little ice Age Climate-Change Social/Political Concern Psychic/Spiritual Implication VOLCANISM Plate Tectonics Peoples’ MIGRATION Northern HEMISPHERE Natural/Cultural Effect-Chains Science Criticism
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