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Probing the Galactic Halo with RR Lyrae *** Radial Velocity Curve Templates of RRc Stars

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Research in Astronomy and Astrophysics 2024年第7期24卷 118-134页

作者： Yue Huang Min Fang Gaochao Liu Xianzhong Zheng Sarah Ann bird Yang Huang Jianrong Shi Jiangtao Wang Huawei Zhang Haijun Tian Haotong Zhang College of Science China Three Gorges UniversityYichang 443002China Center for Astronomy and Space Sciences China Three Gorges UniversityYichang 443002China Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China CAS Key Laboratory of Optical Astronomy National Astronomical ObservatoriesBeijing 100101China Department of Astronomy School of PhysicsPeking UniversityBeijing 100871China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China School of Sciences Hangzhou Dianzi UniversityHangzhou 310018China

We present radial velocity(RV)curve templates of RR Lyrae first-overtone(RRc)stars constructed with the Mg I b triplet and Hαlines using time-domain Medium-Resolution Survey spectra of seven RRc stars from Large Sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST)Data Release ***,we derive the relation between the stellar RV curve amplitudes and g-band light curve amplitudes from Zwicky Transient Facility(ZTF)public *** those RRc stars without ZTF g-band light curves,we provide the conversions from the light curve amplitudes in ZTF r-and i-bands,Gaia G-band,and V-band from the All-Sky Automated Survey for Supernovae to those in ZTF *** validate our RV curve templates using the RRc star SV Scl and find the uncertainties of systemic RV are less than 2.11 km s~(-1)and 6.08 km s~(-1)based on the Mg I b triplet and Hαlines,*** calculate the systemic RVs of 30 RRc stars using the RV curve templates constructed with the Mg I b triplet and Hαlines and find the systemic RVs are comparable with each *** RV curve template will be particularly useful for obtaining the systemic RV of RRc using the LAMOST spectroscopy.

关键词： stars variables RR Lyrae-Stars-techniques radial velocities

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西藏最大内陆湖泊(色林错)溃决及其环境影响（英文）

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Science Bulletin 2024年第18期 2829-2832页

作者：类延斌周璟姚檀栋 Broxton W.bird 于伊凡王淑巾阳坤张寅生翟建青戴玉凤 State Key Laboratory of Tibetan Plateau Earth System Environment and ResourcesInstitute of Tibetan Plateau ResearchChinese Academy of Sciences Department of Earth Sciences Indiana University-Purdue University Indianapolis (IUPUI) College of Resources and Environment University of Chinese Academy of Sciences Ministry of Education Key Laboratory for Earth System Modeling Department of Earth System ScienceTsinghua University National Climate Center China Meteorological Administration

The Tibetan Plateau(TP) and its surroundings are also referred to as ‘‘Asian Water Tower”, which is the headwater of ten major rivers in Asia and provides ecosystem service for nearly two billion people [1]. The interior TP boasts the greatest concentration of high-latitude inland lakes in the world, providing essential water resources, regulating regional climate and maintaining ecological balance. Over the past 50 years, the TP has experienced rapid climate warming and overall wetting, which has led to glacier mass loss, thawing of permafrost, reduction in snow cover, and shortening of lake ice duration [1]. Changes in lake water storage provide a means of assessing the regional hydrological response to recent climate change in this sparsely populated region.

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Organic carbon isotope and molecular fossil records of vegetation evolution in central Loess Plateau since 450 kyr

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Science China Earth Sciences 2016年第6期59卷 1206-1215页

作者： ZHOU Bin WALI Guzalnur Francien PETERSE Michael I bird Key Laboratory of Surficial Geochemistry (Ministry of Education) School of Earth Sciences and Engineering Nanjing University Utrecht University Department of Earth Sciences College of Science Technology and Engineering and Centre for Tropical Environmental and Sustainability Science James Cook University

Significant uncertainties remain regarding the temporal evolution of natural vegetation during the Quaternary, and drivers of past vegetation change, on the Chinese Loess Plateau （CLP）. This study presents analyses of total organic carbon isotopic composition （TOC） and n-alkane ratios （C31/C27） from the Lingtai loess-palaeosol sequence on the central CLP over the last 450 kyr. The results demonstrate that the vegetation in this region comprised a mix of C3 and C4 plants of herb and woody growth-form. C3 plants dominated for most of the last 450 kyr, but this did not lead to extensive forest. C3 woody plants were more abundant in MIS9 （S3 period） and MIS5 （S 1 period） during warm and humid climate conditions. Herbs increased in the region since 130 kyr, possibly as a result of increased aridity. On the orbital timescales, there was a reduction of C3 herbal plants in MIS 11 （$4） than in M1S 12 （L5）, and in Holocene than in the last glacial period. Our isotope and n-alkane proxy records are in agreement with Artemisia pollen changes in the region, which is/was the dominant species in this area and varying due to different heat and water conditions between glacial and interglacial periods. Though the climate in MIS1 （SO） was similar to that in MIS11 （S4）, a significant increase in woody plants during the Holocene suggests the impact of human activities and ecological effects of changes in fire activity.

关键词： Carbon isotopic composition Leaf wax lipids C3/C4 variations Late Quaternary vegetation change Glacial/interglacial cycles

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Natural history of hepatic metastases from colorectal cancer-pathobiological pathways with clinical significance

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World Journal of Gastroenterology 2014年第14期20卷 3719-3737页

作者： Konstantinos A Paschos Ali W Majeed Nigel C bird Liver Research Group Department of OncologySchool of MedicineRoyal Hallamshire HospitalThe University of Sheffield Department of Surgery General Hospital of Drama

Colorectal cancer hepatic metastases represent the final stage of a multi-step biological *** process starts with a series of mutations in colonic epithelial cells,continues with their detachment from the large intestine,dissemination through the blood and/or lymphatic circulation,attachment to the hepatic sinusoids and interactions with the sinusoidal cells,such as sinusoidal endothelial cells,Kupffer cells,stellate cells and pit *** metastatic sequence terminates with colorectal cancer cell invasion,adaptation and colonisation of the hepatic *** these events,termed the colorectal cancer invasion-metastasis cascade,include multiple molecular pathways,intercellular interactions and expression of a plethora of chemokines and growth factors,and adhesion molecules,such as the selectins,the integrins or the cadherins,as well as enzymes including matrix *** review aims to present recent advances that provide insights into these cell-biological events and emphasizes those that may be amenable to therapeutic targeting.

关键词： Colorectal cancer Metastatic cascade Liver metastasis Liver sinusoids Neovascularization

Prediction of tensile power law creep constants from compression and bend data for ZrB_(2)-20 vol% SiC composites at 1800℃

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Journal of Advanced Ceramics 2017年第4期6卷 304-311页

作者： Ali KHADIMALLAH Marc W.bird Kenneth W.WHITE Department of Mechanical Engineering University of HoustonHoustonTXUSA

Here we consider our four-point flexure and compression creep results obtained under Ar protection at 1800℃ to predict the tensile creep behavior of a ZrB_(2)-20 vol%SiC ultra-high temperature *** power law creep,and based on four-point bend data,we estimated the uniaxial creep parameters using an analytical method present in the *** predicted and experimental compressive stress exponents were found to be in excellent agreement,1.85 and 1.76 respectively,while observation of the microstructure suggested a combination of diffusion and grain boundary sliding creep mechanisms in *** with the microstructural evidence associated with the tensile regions of the flexure specimens,the predicted tensile stress exponent of 2.61 exceeds the measured flexural value of *** assert an increasing role of cavitation to the creep strain in pure *** cavitation component adds to the dominant grain boundary sliding mechanism as described below and elsewhere for flexural creep.

关键词： power law creep parameters four-point flexure compression tension creep mechanisms

Social Scale and Collective Computation:Does Information Processing Limit Rate of Growth in Scale?

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Journal of Social Computing 2022年第1期3卷 1-17页

作者： Timothy A.Kohler Darcy bird David H.Wolpert the Department of Anthropology Washington State UniversityPullmanWA 99164-4910USA Santa Fe Institute Santa FeNM 87501USA Crow Canyon Archaeological Center CortezCO 81321USA Cluster of Excellence ROOTS Christian-Albrechts-UniversitätKiel 24118Germany. Max Planck Institute for the Science of Human History Jena 07745Germany the Santa Fe Institute Santa FeNM 87501USA Center for Biosocial Complex Systems Arizona State UniversityTempeAZ 85281USA Complexity Science Hub Vienna 1080Austria

Collective computation is the process by which groups store and share information to arrive at decisions for collective *** societies engage in effective collective computation depends partly on their *** arrangements and technologies that work for small-and mid-scale societies are inadequate for dealing effectively with the much larger communication loads that societies face during the growth in scale that is a hallmark of the *** important bottleneck for growth may be the development of systems for persistent recording of information(writing),and perhaps also the abstraction of money for generalizing exchange *** on Shin et al.,we identify a Scale Threshold to be crossed before societies can develop such systems,and an Information Threshold which,once crossed,allows more or less unlimited growth in *** introduce several additional articles in this special issue that elaborate or evaluate this Thresholds Model for particular types of societies or times and places in the world.

关键词： social evolution thresholds model information processing writing demographic scale collective computation

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午餐肉鸡蛋饼

饮食科学 2024年第5期 45-45页

作者：黄莺bird-Xu(文/图) 不详

用料。手抓饼1张,鸡蛋1个,午餐肉适量,香葱适量。做法1.午餐肉切成条。2.平底锅中放入手抓饼,放上午餐肉条,围成一个方形。3.打入1个鸡蛋,将手抓饼上下叠成一个方形饼。4.小火煎至两面金黄,摆盘即食。

关键词：午餐肉鸡蛋饼手抓饼即食方形用料

On the mechanical behavior of the human biliary system

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World Journal of Gastroenterology 2007年第9期13卷 1384-1392页

作者： Xiaoyu Luo Wenguang Li Nigel bird Swee Boon Chin NA Hill Alan G Johnson Department of Mathematics University of Glasgow Glasgow G12 8QW United Kingdom Department of Mechanical Enginwring University of Sheffield Sheffield S1 3JD United Kingdom Academic Surgical Unit Royal Hallamshirc Hospital Sheffield S10 2JF United Kingdom

This paper reviews the progress made in understanding the mechanical behaviour of the biliary system. Gallstones and diseases of the biliary tract affect more than 10% of the adult population. The complications of gallstones, i.e. acute pancreatitis and obstructive jandice, can be lethal, and patients with acalculous gallbladder pain often pose diagnostic difficulties and undergo repeated ultrasound scans and oral cholecystograms. Moreover, surgery to remove the gallbladder in these patients, in an attempt to relieve the symptoms, gives variable results. Extensive research has been carried out to understand the physiological and pathological functions of the biliary system, but the mechanism of the pathogenesis of gallstones and pain production still remain poorly understood. It is believed that the mechanical factors play an essential role in the mechanisms of the gallstone formation and biliary diseases. However, despite the extensive literature in clinical studies, only limited work has been carried out to study the biliary system from the mechanical point of view. In this paper, we discuss the state of art knowledge of the fluid dynamics of bile flow in the biliary tract, the solid mechanics of the gallbladder and bile ducts, recent mathematical and numerical modelling of the system, and finally the future challenges in the area.

关键词： Fluid dynamics Gallstone Bile flow Cystic duct Gallbladder Soft tissue mechanics Acalculousbiliary pain Stress Mechanical factors

Highly refractory Archaean peridotite cumulates:Petrology and geochemistry of the Seqi Ultramafic Complex,SW Greenland

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Geoscience Frontiers 2018年第3期9卷 689-714页

作者： Kristoffer Szilas Vincent van Hinsberg Iain McDonald Tomas Naeraa Hugh Rollinson Jacob Adetunji Dennis bird Department of Geological Sciences Stanford University450 Serra MallStanfordCA 94305USA Department of Earth&Planetary Sciences McGill UniversityQuebecCanada Department of Geology Lund UniversitySovegatan 12223 62 LundSweden School of Earth and Ocean Sciences Cardiff UniversityMain BuildingCardiff CF10 3ATUnited Kingdom College of Science University of DerbyDerbyDE22 1GBUK

This paper investigates the petrogenesis of the Seqi Ultramafic Complex, which covers a total area of approximately 0.5 km^2. The ultramafic rocks are hosted by tonalitic orthogneiss of the ca. 3000 Ma Akia terrane with crosscutting granitoid sheets providing an absolute minimum age of 2978 ± 8 Ma for the Seqi Ultramafic Complex. The Seqi rocks represent a broad range of olivine-dominated plutonic rocks with varying modal amounts of chromite, orthopyroxene and amphibole, i.e. various types of dunite(s.s.),peridotite(s.l.), as well as chromitite. The Seqi Ultramafic Complex is characterised primarily by refractory dunite, with highly forsteritic olivine with core compositions having Mg# ranging from about 91 to 93. The overall high modal contents, as well as the specific compositions, of chromite rule out that these rocks represent a fragment of Earth's mantle. The occurrence of stratiform chromitite bands in peridotite, thin chromite layers in dunite and poikilitic orthopyroxene in peridotite instead supports the interpretation that the Seqi Ultramafic Complex represents the remnant of a fragmented layered complex or a magma conduit, which was subsequently broken up and entrained during the formation of the regional continental *** all of the characteristics of the Seqi Ultramafic Complex points to formation of these highly refractory peridotites from an extremely magnesian(Mg# ~ 80), near-anhydrous magma, as olivinedominated cumulates with high modal contents of chromite. It is noted that the Seqi cumulates were derived from a mantle source by extreme degrees of partial melting(>40%). This mantle source could potentially represent the precursor for the sub-continental lithospheric mantle(SCLM) in this region,which has previously been shown to be ultra-depleted. The Seqi Ultramafic Complex, as well as similar peridotite bodies in the Fiskefjord region, may thus constitute the earliest cumulates that formed during the large-scale melting event(s), which

关键词： North Atlantic Craton Archaean Dunite Platinum-group elements Ultra-depleted mantle Fiskefjord

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