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Palaeolake and palaeoenvironment between 42 and 18 kaBP in Tengger desert,NW China

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Chinese Science Bulletin 2002年第23期47卷 1946-1956页

作者： H.j.Pachur B.Wünnemann National Laboratory of Western China's Environmental Systems MOE Lanzhou University Lanzhou 730000 China Nanjing Institute of Geology and Paleontology Academia Sinica Nanjing 210008 China Geolaboratory Institute of Geographical Sciences Free University of Berlin Malteser Str. 74-100 12249 Berlin Germany

Comprehensive field investigations and laboratory analyses show that palaeolakes, including fresh-mesohaline water Megalake Tengger and other semi-connected, isolated water bodies, during late Pleistocene covered an area of more than 20000 km2, which is more than half of the Tengger desert in NW China. Stratigraphic correlation and chronological evidence indicate that before ca. 42000 aBP the area was more arid. The palaeolakes started to develop around 40000 uncal. 14C aBP but until 37000 14C aBP their scope was limited. High water levels established from 35000 14C aBP lasted until 22000 14C aBP. Lake levels regressed between 22000 and 20000 14C aBP but transgressed from 20000 to 18600 14C aBP. Subsequently, water level declined further and the Megalake Tengger finally desiccated at around 18000 14C aBP. Megalake Tengger possessed a fresh-mesohaline water property, implying that the regional precipitation increased significantly. During the period of Megalake Tengger, the climate was warmer-humid

关键词： Tengger desert palaeolake palaeoenvironment NW China.

Reviewing the Safe Shipping of Lithium-Ion and Sodium-Ion Cells:A Materials Chemistry Perspective

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Energy Material Advances 2021年第1期2021卷 1-12页

作者： Ashish Rudola Christopher j.Wright jerry Barker Faradion Limited The Innovation Centre217 PortobelloSheffield S14DPUK

High energy density lithium-ion(Li-ion)batteries are commonly used *** decades’worth of intense research has led to a good understanding on several aspects of such ***,the issue of their safe storage and transportation is still not widely understood from a materials chemistry *** international regulations require Li-ion cells to be shipped at 30%SOC(State of Charge)or *** this article,the reasons behind this requirement for shipping Li-ion batteries are firstly reviewed and then compared with those of the analogous and recently commercialized sodium-ion(Na-ion)*** such alkali-ion batteries,the safest state from their active materials viewpoint is at 0V or zero energy,and this should be their ideal state for storage/***,a“fully discharged”Li-ion cell used most commonly,composed of graphitebased anode on copper current collector,is not actually at 0V at its rated 0%SOC,contrary to what one might expect—the detailed mechanism behind the reason for this,namely,copper dissolution,and how it negatively affects cycling performance and cell safety,will be summarized *** will be shown that Na-ion cells,capable of using a lighter and cheaper aluminum current collector on the anode,can actually be safely discharged to 0V(true 0%SOC)and beyond,even to reverse polarity(negative voltages).It is anticipated that this article spurs further research on the 0V capability of Na-ion systems,with some suggestions for future studies provided.

关键词： cycling summarized alkali

A Rare Case of Concordant Atrioventricular Connection to L-Looped Ventricles in Situs Solitus:4-Dimensional Magnetic Resonance Imaging and 3D Printing

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Congenital Heart Disease 2022年第4期17卷 387-392页

作者： Gregory Perens Takegawa Yoshida j.Paul Finn UCLA Mattel Children’s Hospital Children’s Heart CenterLos AngelesCAUSA Diagnostic Cardiovascular Imaging Laboratory Department of Radiology12222 David Geffen School of Medicine at UCLALos AngelesCAUSA

An infant male presented with the rare anatomy consisting of situs solitus,concordant atrioventricular connections to L-looped ventricles,double outlet right ventricle(DORV),and hypoplastic aortic arch.6 months after neonatal aortic arch repair,the morphologic right ventricle function deteriorated,and surgical evaluation was undertaken to determine if either biventricular repair with a systemic morphologic left ventricle or right ventricular exclusion was *** initial echocardiography,magnetic resonance imaging(MRI)was used to create detailed axial and 4-dimensional(4D)images and 3-dimensional(3D)printed *** detailed anatomy of this rare,complex case and its use in pre-surgical planning is presented.

关键词： Magnetic resonance imaging cardiac segments 3D printing

Sample Size dependence of Second Magnetizaion Peak in Type-ⅡSuperconductors

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Tsinghua Science and Technology 2003年第3期8卷 370-378页

作者： j.H.S.Torres Y.Kopelevich Institute de fisica"Gleb Wataghin" Universitade Estadual de CampinasUnicamp 13083-970CampinasSao PauloBrasilInstitute de fisica"Gleb Wataghin"Universitade Estadual de CampinasUnicamp 13083-970CampinasSao PauloBrasil

We show that the second magnetization peak(SMP),i.e.,an increase in the magnetization hysteresis loop width in type-11 superconductors,vanishes for samples smaller than a critical size,We argue that the SMP is not related to the critical current enhancement but can be well explainde within a frameword of the thermomagenetic flux-jump in stability theory,where flux jumps reduce the absolute irreversible magnetization relative to the isothermal critical state value at low enough magnetic *** recovering of the isothermal critical sate with increasing field leads to the *** low-field SMP takes place in both *** and high**** *** results show that the rsstoration of the isothermal critical state is rsponsible for the SMP occurrence in both cases.

关键词： Superconductor flux pinning and creep peekeffect phase transityons

基于轻量级j2EE的加油站卡系统的设计与实现

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计算机工程与设计 2009年第21期30卷 4969-4971,4994页

作者：马钟宇倪德明中山大学软件学院广东广州510275

为了有效构建一套加油站卡系统,在探讨了问题域及不同实现框架优缺点的基础上,给出了一个基于轻量级j2EE框架的实现方案。此方案根据卡系统自身的需求和特点,在开发过程中充分利用轻量级j2EE先进的体系架构,并详细阐述如何通过使用Sprin... 详细信息

为了有效构建一套加油站卡系统,在探讨了问题域及不同实现框架优缺点的基础上,给出了一个基于轻量级j2EE框架的实现方案。此方案根据卡系统自身的需求和特点,在开发过程中充分利用轻量级j2EE先进的体系架构,并详细阐述如何通过使用Spring、Hibernate、Acegi等多个成熟开源框架来简化系统开发的复杂性,同时提高开发效率。系统的运行结果表明此设计方案的合理性和有效性,也为其它类似应用提供了一个通用的解决方案。

关键词：加油站卡系统轻量级j2EE体系结构 Spring框架 Hibernate框架 Acegi框架

The number of alignments between two DNA sequences

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International journal of Biomathematics 2016年第4期9卷 75-80页

作者： Helena Andrade juan j. Nieto Angela Torres departamento de Andlisis Matemdtico Facultad de Matemdticas Universidad de Santiago de Compostela Spain department of Mathematics Faculty of ScienceKing Abdulaziz University Jeddah 21589 Saudi Arabia departamento de Psiquiatrla Radiologla y Salud Publica Facultad de Medicina Universidad de Santiago de Compostela Spain

We consider two DNA sequences and compare both sequences. One of the crucial issues in bioinformatics is to measure the similarity of two DNA sequences. To this purpose one has to consider different alignments between both sequences. The number of alignments grows very rapidly with the length of the sequences. In this paper we give exact, explicit and computable formulas for the number of different possible alignments and for some classes of reduced alignments. We provide a new insight into the theory of DNA sequence alignment.

关键词： DNA sequence alignment difference equation.

Advancements in the mind-machine interface:towards re-establishment of direct cortical control of limb movement in spinal cord injury

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Neural Regeneration Research 2016年第7期11卷 1060-1061页

作者： jian Guan Gregory W.j.Hawryluk department of Neurosurgery Clinical Neurosciences CenterUniversity of Utah

Spinal cord injury（SCI）resulting in loss of motor function can be caused by a variety of conditions,ranging from traumatic to neoplastic to *** is estimated that nearly 300,000individuals live with the effects of SCI in the United States alone（National Spinal Cord Injury Statistical Center,2016）.Current treatment modalities for patients suffering from SCI are primarily supportive,

关键词： cortical modalities neoplastic alone traumatic restoration suffering cortex options infectious

Immune response to H pylori

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World journal of Gastroenterology 2006年第35期12卷 5593-5598页

作者： Giovanni Suarez Victor E Reyes Ellen j Beswick department of Pediatrics University of Texas Medical Branch Galveston TX 77555 United States department of Microbiology and Immunology University of Texas Medical Branch Galveston TX 77555United StatesDepartment of Microbiology and Immunol-ogy University of Texas Medical Branch Galveston TX 77555 United States

The gastric mucosa separates the underlying tissue from the vast array of antigens that traffic through the stomach lumen. While the extreme pH of this environment is essential in aiding the activation of enzymes and food digestion, it also renders the gastric epithelium free from bacterial colonization, with the exception of one important human pathogen, Hpylori. This bacterium has developed mechanisms to survive the harsh environment of the stomach, actively move through the mucosal layer, attach to the epithelium, evade immune responses, and achieve persistent colonization. While a hallmark of this infection is a marked inflammatory response with the infiltration of various immune cells into the infected gastric mucosa, the host immune response is unable to clear the infection and may actually contribute to the associated pathogenesis. Here, we review the host responses involved during infection with Hpylori and how they are influenced by this bacterium.

关键词： H pylori Immune response T cell dendritic cells

MOdeLING HEADCUT deVELOPMENT AND MIGRATION IN UPLAND CONCENTRATED FLOWS

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International journal of Sediment Research 2005年第4期20卷 281-294页

作者： Sean j. BENNETT Carlos V. ALONSO department of Geography University at Buffalo Buffalo NY 14261-0055 USA USDA-ARS National Sedimentation Laboratory P.O. Box 1157 Oxford MS 38655

On hillslopes and agricultural fields, discrete areas of intense, localized soil erosion commonly take place in the form of migrating headcuts. These erosional features significantly increase soil loss and landscape degradation, yet the unsteady, transient, and migratory habits of headcuts complicate their phenomenological and erosional characterization. Here a unique experimental facility was constructed to examine actively migrating headcuts typical of upland concentrated flows. Essential components of the facility include a deep soil cavity with external drainage, rainfall simulator, capacity for overland flow, and a video recording technique for data collection. Results from these experiments show that: (1) after a short period of adjustment, headcut migration attained a steady-state condition, where the rate of migration, scour hole geometry, and sediment discharge remain constant with time; (2) boundary conditions of higher rates of overland flow, steeper bed slopes, and larger initial headcut heights produced systematically larger scour holes with higher rates of soil erosion; and (3) during migration, the turbulent flow structure within the scour hole remained unchanged, consisting of an overfall nappe at the brink transitioning into a reattached wall jet with two recirculation eddies within the plunge pool. The systematic behavior of headcut development and migration enabled the application of modified jet impingement theory to predict with good success the characteristics of the impinging jet, the depth of maximum scour, the rate of headcut migration, and the rate of sediment erosion. These laboratory data and the analytical formulation can be used in conjunction with soil erosion prediction technology to improve the management of agricultural areas impacted by headcut development and ephemeral gully erosion.

关键词： Soil erosion Headcuts Rills Gullies jet impingement