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A mid-Holocene drought interval as evidenced by lake desiccation in the Alashan Plateau, Inner Mongolia, china

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Science Bulletin 2003年第14期48卷 1401-1410页

作者： J.A.Holmes D.B.Madsen C.g.oviatt USA University College-London Desert Research Institute Department of geography Environmental change Research Center WC1H 0AP KS 66506 USA Correspondence should be addressed to chen Fahu Department of geology Reno Kansas State University London NV 89512 Division of Earth and Ecosystem Sciences Manhattan UK

The mid-Holocene in china is traditionally thought to be a warm and humid period with a strong summer monsoon, and is often termed the Holocene Climatic Optimum or Megathermal Period. Here we present lake geomorphologic and lithological evidence from the Alashan Plateau, part of the Mongolian Plateau, that indicates strong lake desiccation during the mid-Holocene. High resolution pollen data from Zhuyeze Lake, at the present summer monsoon margin, is also presented. These data show that present lakes and wetlands in the Juyanze Lake basin west of the Badain Jaran desert, in the Zhuyeze Lake basin between the Badain Jaran and Tengger deserts, and in lakes in the eastern Tengger desert, dried or experienced low lake levels in the mid-Holocene around 5000—7000 cal yr BP. Pollen data further indicate that the vegetation cover declined in both the local areas and in the Qilian Mountains, suggesting the climate was drier than that associated with the present Asian summer monsoon. This mid-Holocene drought interval was present throughout a quite large region of the south Inner Mongolian Plateau. The period was also probably colder, at least in the high Asian plateaus and mountains.

关键词： western Inner Mongolian Plateau mid-Holocene lake desiccation dry climate.

An SPH Framework for Earthquake-Induced Liquefaction Hazard Assessment of geotechnical Structures

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 251-277页

作者： Sourabh Mhaski g.V.Ramana Department of Civil Engineering Indian Institute of Technology DelhiNew Delhi110016India

Earthquake-induced soil liquefaction poses significant risks to the stability of geotechnical structures *** understanding of the liquefaction triggering,and the post-failure large deformation behaviour is essential for designing resilient *** present study develops a Smoothed Particle Hydrodynamics(SPH)framework for earthquake-induced liquefaction hazard assessment of geotechnical *** coupled flowdeformation behaviour of soils subjected to cyclic loading is described using the PM4Sand model implemented in a three-phase,single-layer SPH framework.A staggered discretisation scheme based on the stress particle SPH approach is adopted to minimise numerical inaccuracies caused by zero-energy modes and tensile ***,non-reflecting boundary conditions for seismic analysis of semi-infinite soil domains using the SPH method are *** numerical framework is employed for the analysis of cyclic direct simple shear test,seismic analysis of a level ground site,and liquefaction-induced failure of the Lower San Fernando *** agreement for liquefaction triggering and post-failure behaviour demonstrates that the SPH framework can be utilised to assess the effect of seismic loading on field-scale geotechnical *** present study also serves as the basis for future advancements of the SPH method for applications related to earthquake geotechnical engineering.

关键词： Earthquake seismic liquefaction stress particle PM4Sand smoothed particle hydrodynamics(SPH)

Stepping up after spinal cord injury:negotiating an obstacle during walking

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Neural Regeneration Research 2025年第7期20卷 1919-1929页

作者： Alain Frigon charly g.Lecomte Department of Pharmacology-Physiology Faculty of Medicine and Health SciencesUniversitéde SherbrookeCentre de recherche du Centre Hospitalier Universitaire de SherbrookeSherbrookeQCCanada

Every day walking consists of frequent voluntary modifications in the gait pattern to negotiate *** spinal cord injury,stepping over an obstacle becomes *** over an obstacle requires sensorimotor transformations in several structures of the brain,including the parietal cortex,premotor cortex,and motor *** information and planning are transformed into motor commands,which are sent from the motor cortex to spinal neuronal circuits to alter limb trajectory,coordinate the limbs,and maintain *** spinal cord injury,bidirectional communication between the brain and spinal cord is disrupted and animals,including humans,fail to voluntarily modify limb trajectory to step over an ***,in this review,we discuss the neuromechanical control of stepping over an obstacle,why it fails after spinal cord injury,and how it recovers to a certain extent.

关键词： biomechanics locomotion neurophysiology obstacle negotiation spinal cord injury

Projective Hilbert modules and sequential approximations

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Science china Mathematics 2025年第1期 137-168页

作者： Lawrence g.Brown Huaxin Lin Department of Mathematics Purdue University Department of Mathematics East China Normal University Department of Mathematics University of Oregon Shanghai Institute for Mathematics and Interdisciplinary Sciences

We show that when A is a separable C*-algebra,every countably generated Hilbert A-module is projective（with bounded module maps as morphisms）.We also study the approximate extensions of bounded module *** the case where A is a σ-unital simple C*-algebra with strict comparison,and every strictly positive lower semicontinuous affine function on quasitraces can be realized as the rank of an element in the Cuntz semigroup,we show that the Cuntz semigroup is equivalent to unitarily equivalent classes of countably generated Hilbert A-modules if and only if A has stable rank one.

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Kinetic Instability of Anisotropic Drift Wave Accompanied by Field Aligned Currents in Solar Coronal Loop

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Communications in Theoretical Physics 2018年第10期70卷 470-476页

作者： Hafsa Naim ch.Uzma g.Murtaza Salam chair Department of Physics GC University

Solar coronal loops are frequently accompanied by the field-aligned currents, which drive instabilities if the drift velocity u0 > v A the Alfv′en velocity. For our choice of parameters, the critical threshold value of u0/v A is ～ 3.0 for growth and the corresponding current filling factor ～ 10-3-10-4. Below this value we are no longer in the kinetic *** coronal loops also have short-scale density gradients within each loop. The electron resonance in the presence of density gradient causes the drift mode to grow. We study the effect of these two free energy sources, the electron drift and the density gradient, in the presence of temperature anisotropy T⊥_α > T∥_α. These effects simultaneously exist in the coronae. Using gyrokinetic theory, we investigate the influence of these effects, examine how they interplay with each other and study the consequent growth of the magnetosonic wave. We observe that kinetic instability driven by density gradient can be suppressed by field-aligned currents. The temperature anisotropy with chosen signatures causes further stabilizing effect. The results may prove useful to study the heating mechanism of solar coronal loops, acceleration of particles and confinement of particles in the thermonuclear reactors.

关键词： solar corona coronal loops temperature anisotropy density inhomogeneity field-aligned currents gyrokinetic

Copy-Move Forgery Verification in Images Using Local Feature Extractors and Optimized Classifiers

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Big Data Mining and Analytics 2023年第3期6卷 347-360页

作者： S.B.g.Tilak Babu ch Srinivasa Rao University College of Engineering JNTU KakinadaKakinada 533003India. Department of ECE JNTUK UCEVizianagaram 535003India.

Passive image forgery detection methods that identify forgeries without prior knowledge have become a key research *** copy-move forgery,the assailant intends to hide a portion of an image by pasting other portions of the same *** detection of such manipulations in images has great demand in legal evidence,forensic investigation,and many other *** paper aims to present copy-move forgery detection algorithms with the help of advanced feature descriptors,such as local ternary pattern,local phase quantization,local gabor binary pattern histogram sequence,Weber local descriptor,and local monotonic pattern,and classifiers such as optimized support vector machine and optimized *** proposed algorithms can classify an image efficiently as either copy-move forged or authenticated,even if the test image is subjected to attacks such as JPEg compression,scaling,rotation,and brightness ***,CASIA,and MICC datasets and a combination of CoMoFoD and CASIA datasets images are used to quantify the performance of the proposed *** proposed algorithms are more efficient than state-of-the-art algorithms even though the suspected image is post-processed.

关键词： copy move forgery detection image authentication passive image forgery detection blind forgery detection

Preliminary research on Megalake Jilantai-Hetao in the arid areas of china during the Late Quaternary

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chinese Science Bulletin 2008年第11期53卷 1725-1739页

作者： chEN FaHu FAN YuXin chUN Xi D.B. MADSEN C.g. oviatt ZHAO Hui YANg LiPing SUN Yang MOE Key Laboratory of Western china's Environmental Systems Lanzhou University Lanzhou 730000 China Texas Archeological Research Laboratory University of Texas Austin TX 78712 USA geology Department Kansas State University Manhattan KS 66506 USA Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

我们识别了 geomorphological，在通过地调查并且通过地区性的遥感的分析的当前的 Jilantai 盐湖附近的高湖层次的沉积、生物的证据想象。在约 1060， 1050， 1044 和 1035 m a.s.l 的举起有四组海岸线，是在当前的盐湖上面的 37， 27，... 详细信息

我们识别了 geomorphological，在通过地调查并且通过地区性的遥感的分析的当前的 Jilantai 盐湖附近的高湖层次的沉积、生物的证据想象。在约 1060， 1050， 1044 和 1035 m a.s.l 的举起有四组海岸线，是在当前的盐湖上面的 37， 27， 21 和 12 m 分别地出现。沙和石子的沿岸的存款在在 1070 和 1080 m a.s.l 之间的举起被发现，比水流高的 47 ～ 57 m 腌湖表面，尽管 palaeoshoreline 地形仅仅在几个地点被保存。在 Herimuxini，在 Ulan Buh 荒芜的、典型湖的沉积和沙石子的北边缘上，沿岸的存款也发生在 1080 m a.s.l 并且在下面的举起。典型吐痰扩大的 A 11-km-long 从逐渐地在它的大拐弯上沿着黄河的南部的银行在一些沙石子石场从 1050 ～ 1035 m a.s.l 在举起减少的这条海岸线东方海岸线特征例如在水文学计量器车站和 Shilazhao 镇附近定位的那些，被识别。沿岸的存款 overlying 冲积的洪水的层在 Hangjin 在 Balagong 附近发生在沙石场县。也有沙滩岩石和沿岸的存款，沿着 Langshan-Yinshan 山的南部的山麓在几个地点在 cut-and-built 平台上保存。另外，揭示水下的三角洲沉积的侧面在 Wuhai 附近被识别，在黄河进入盆的地方。典型的湖沉积也在 Hetao 平原的东方结束在 Togtoh 站台存在。水的软体动物壳在沿岸的存款是普通的，包括 Corbicula 的几种，根值 lagotis， R。xauricularia 和 gyraulus convexiusculus。Ostracode 壳能也在更好的沉积被识别。典型垂直 prograding 序列在湖的沉积很好被保存的露头是明显的。滚动波浪的卵石和沙滩岩石很通常在更高的举起在堤在侧面的顶上被保存。所有这些证据建议曾经有一个巨大的palaeo湖，用到达我们指的 ∼1080 m a.s.l 的最高的湖水平盖住 Jilantai 区域和 Hetao 平原的大多数部分巨大的 paleolake ，比现代的湖贝加尔湖大，作为“ Megalake Jilantai-Hetao ”. OSL 标明日期结果显示大湖以前形成了 ∼60 —50 ka，和在在 1060 和 1035 m a.s.l 之间的举起的四条海岸线多半从 ∼60 ∼50 ka 代表湖水平变化到早 Holocene。Megalake Jilantai-Hetao 的发现将多半影响黄河的发展的理解在期间晚第四级， Ulan Buh 和 Kubq 的进化抛弃，在这个区域的 neotectonism，并且可能地区性的气候的变化。

关键词：中国晚第四纪干旱地区古气候学

Bioelectronic medicine in modulation of cortical spreading depolarization and beyond

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Neural Regeneration Research 2025年第2期20卷 481-482页

作者： Khaled Alok Timothy g.White chunyan Li Department of Neurosurgery Donald and Barbara Zucker School of Medicine at Hofstra/NorthwellHempsteadNYUSA Translational Brain Research Laboratory The Feinstein Institutes for Medical ResearchManhassetNYUSA

Bioelectronic interventions,specifically trigeminal nerve st imulat ion(TNS),have attracted considerable attention in conditions where cortical spreading depolarizations(CSDs)accompanied by compromised cerebral perfusion may exacerbate neurological *** pharmacological interventions have demonstrated initial potential in addressing CSDs,a standardized treatment approach has not yet been *** objective of this perspective is to explore emerging bioelectronic methodologies for addressing CSDs,particularly emphasizing TNS,and to underscore TNS’s capacity to enhance neurovascular coupling and cerebral perfusion.

关键词： cerebral perfusion electronic

Malaria prevalence in north-eastern Nigeria:A cross-sectional study Houben ch^(1*),Fleischmann H^2,gǜckel M^3

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Asian Pacific Journal of Tropical Medicine 2013年第11期6卷 865-868页

作者： Houben ch Fleischmann H gckel M Diagnostic Center MMM group & Specialist Hospital Yola Hospital RoadP.M.B.2266YolaAdamawa.StateNigeria Medical Mission Institute Tropical MedicineHermann Schell Str 797074 WrzburgGermany Helios Kliniken Schwerin Wismarsche Str 393-39719049 SchwerinGermany

Objective:To assess the prevalence of malaria parasitemia in north-east Nigeria and to evaluate the measures for the prevention of ***:A village in north-eastern Nigeria was selected for the cross sectional study at the height of the rainy season in October 2011.A total of 550 inhabitants of a hamlet were recruited for this *** obtaining the consent individuals received a structured interview and were tested for malaria parasites in their blood *** testing positive for malaria were given a course of artemesinin-based combination therapy（ACT）.Results:A total of 497 inhabitants representing approximately 90 percent of the population participated:a quarter of the study group carried malaria parasitesexclusively Plasmodium falciparum（***）-representing a *** parasite rate（PfPR） of 24.5%.Besides,53/138 in the age group of 2 to children tested positive for *** representing a PfPR2-10 value of 38.4%.Malaria control measures were used in just under a third（157/497） of this *** these measures 28/157（17.8%） still tested positive for ***:The malaria burden is overestimated for this region in north-east *** findings support an intermediate pattern of malaria *** 30%bed nets coverage for malaria control is well below the WHO estimates for 2011.

关键词： Malaria control Malaria endemicity Malaria prevalence Malaria transmission