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NEAR'S CLOSE fLYBY Of C-TYPE ASTEROID 253 MATHILDE

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紫金山天文台台刊 1998年第2期 44-50页

作者： james f.Bell III the NEAR Science Team Cornell University Department of Astronomy Ithaca NY 14853-6801 USA

On June 27, 1997, the Near Earth Asteroid Rendezvous (NEAR) spacecraft flew within 1200km of the main belt asteroid 253 Mathilde. Previous observations of Mathilde had revealed it to be a C-type asteroid with an astonishingly-long rotation period of 17.4 days, an albedo of 3.8%, and a mean diameter of 60 km. Observations by NEAR reveal that Mathilde has a roughly triaxial shape of 66 × 48 × 46 km diameter and a mass of 1. 02 × 10 g, implying a mean density of only 1. 3g/cm3 . The surface of Mathilde was observed to be saturated with large impact craters, showing a range of visible topography in excess of 5 km. Multispectral observations did not reveal any substantial color differences across the surface, and coverage at multiple phase angles was used to derive a preliminary albedo of 3. 5 % to 5% .The low observed density, lack of color variations, and low albedo all suggest that Mathilde may be a primitive, carbon - rich object with an interior that contains substantial pore space.

关键词：小行星飞船紫金山天文台探测

Geochemistry,petrology,and palynology of the Princess No.3 coal,Greenup County,Kentucky

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International Journal of Coal Science & Technology 2020年第4期7卷 633-651页

作者： Madison M.Hood Cortland f.Eble james C.Hower Shifeng Dai Center for Applied Energy Research University of Kentucky2540 Research Park DriveLexingtonKY 40511USA Department of Earth and Environmental Sciences University of KentuckyLexingtonKY 40506USA Kentucky Geological Survey LexingtonKY 40506USA State Key Laboratory of Coal Resources and Safe Mining China University of Mining and TechnologyBeijingChina School of Resources and Geosciences China University of Mining and TechnologyXuzhou 221116China Present Address:Department of Geosciences Baylor UniversityWacoTX 76798USA

The high volatile C bituminous-rank,Bolsovian-age Princess No.3 coal,a correlative of the heavily-mined Hazard No.7 coal and the Peach Orchard and Coalburg Lower Split coals,was investigated three sites at a mine in Greenup County,*** coal exhibits a“dulling upwards”trend,with decreasing vitrinite and a greater tendency towards dull clarain and bone lithotypes towards the top of the *** relatively vitrinite-rich basal lithotype is marked by a dominance of lycopod tree *** palynology transitions upwards to a middle parting co-dominated by tree fern and small lycopod spores and an upper bench dominated by tree ferns with contributions from small ferns,cordaites,and *** lithotypes generally have a moderate-to high-S content with a variable ash ***,fe2O3,and certain siderophile elements are highest near the top of the *** observed in other coals,uranium and Ge are enriched at the top and bottom margins of the *** rare earth chemistry at the top of the coal has a significantly lighter distribution(higher LREE/HREE)than at the base of the coal.

关键词： Maceral Rare earth elements Lanthanides Coal lithology

Review of Mercury's dynamic magnetosphere:Post-MESSENGER era and comparative magnetospheres

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Science China Earth Sciences 2022年第1期65卷 25-74页

作者： Weijie SUN Ryan MDEWEY Sae AIZAWA Jia HUANG james A.SLAVIN Suiyan fU Yong WEI Charles f.BOWERS Department of Climate and Space Sciences and Engineering University of MichiganAnn ArborMl 48109USA Institut de Recherche en Astrophysique et Planetologie CNRS-UPS-CNESToulouse 31400France Department of Geophysics Graduate School of ScienceTohoku UniversitySendai 980-8578Japan School of Earth and Space Sciences Peking UniversityBeijing 100871China Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China School of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100864China

This review paper summarizes the research of Mercury’s magnetosphere in the Post-MESSENGER era and compares its dynamics to those in other planetary magnetospheres,especially to those in Earth’s *** review starts by introducing the planet Mercury,including its interplanetary environment,magnetosphere,exosphere,and conducting *** frequent and intense magnetic reconnection on the dayside magnetopause,which is represented by the flux transfer event"shower",is reviewed on how they depend on magnetosheath plasma β and magnetic shear angle across the magnetopause,followed by how it contributes to the flux circulation and magnetosphere-surface-exosphere *** the next,Mercury’s magnetosphere under extreme solar events,including the core induction and the reconnection erosion on the dayside magnetosphere,as well as the responses of the nightside magnetosphere,are ***,the dawn-dusk properties of the plasma sheet,including the features of the ions,the structure of the current sheet,and the dynamics of magnetic reconnection,are *** last topic is devoted to the particle energization in Mercury’s magnetosphere,which includes the energization of the Kelvin-Helmholtz waves on the magnetopause boundaries,reconnection-generated magnetic structures,and the cross-tail electric *** each chapter,the last section discusses the open questions related to each topic,which can be considered by the simulations and the future spacecraft *** end this paper by summarizing the future Bepi Colombo opportunities,which is a joint mission of ESA and JAXA and is en route to Mercury.

关键词： Mercury’s magnetosphere flux transfer event shower Extreme solar events Core induction Reconnection erosion Dawn-dusk asymmetry Substorm current wedge Particle energization Kelvin-Helmholtz wave

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Effects of disturbance on small mammal community structure in the New Jersey Pinelands, USA

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Integrative Zoology 2012年第1期7卷 16-29页

作者： Alicia N.SHENKO Walter f.BIEN james R.SPOTILA Harold W.AVERY Department of Biology Drexel UniversityPhiladelphiaPennsylvaniaUSA

We compared small mammal community composition among undisturbed habitats and habitats disturbed by military operations on Warren Grove Gunnery Range(WGR)in the New Jersey *** is one of the largest tracts of protected land within this globally rare *** in the form of fire,mowing,soil disruption and logging has had a large effect on small mammal occurrence and *** the 14 small mammal species that occur in the Pinelands,9 live on WGR,including large populations of the southern bog lemming(Synaptomys cooperi Baird,1858)and meadow jumping mouse[Zapus hudsonius(Zimmermann,1780)].Simpson’s Index of Diversity was 0 for most disturbed sites and was generally greater in wetlands than in ***-footed mouse[Peromyscus leucopus(Rafinesque,1818)]was the most common species on WGR and had a dominant effect on species diversity and community similarity *** dominated upland habitats and was the only species to occur in several disturbed habitats,whereas all 9 species occurred in *** components analysis indicated that most variation in species diversity was explained by disturbance and differences between upland and wetland habitats,due to presence of white-footed mice in disturbed and upland *** jumping mice,southern bog lemmings and red-back voles[Myodes gapperi(Vigors,1830)]were positively correlated with wetland habitats,and pine voles[Microtus pinetorum(Le Conte,1830)],short-tail shrews[Blarina brevicauda(Say,1823)]and eastern chipmunks[Tamias striatus(Linnaeus,1758)]were associated with *** heterogeneity at WGR,including extensive undisturbed wetlands and uplands supported a rich diversity of small mammal species.

关键词： disturbance mice military training Pine Barrens southern bog lemming

Association of Varroa destructor females in multiply infested cells of the honeybee Apis mellifera

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Insect Science 2019年第1期26卷 128-134页

作者： Alexis L.Beaurepaire james D.Ellis Klemens J.Krieger Robin f.A.Moritz Institut for Biologie Martin-Luther-University Halle-WittenbergHalle a.d.SaaleGermany UR 406 Abeilles et Environnement INRACentre de Recherche Provence-Alpes-Cote d'AzurAvignonFrance Entomology &Nematology Department University Florida GainesvilleFloridaUSA Bayer Animal Health GmbH LeverkusenGermany Department of Zoology and Entomology University of PretoriaPretoriaSouth Africa

The genetic diversity of Varroa destructor (Anderson &Trueman)is limited outside its natural range due to population bottlenecks and its propensity to *** light of the arms race between *** and its honeybee (Apis mellifera L.)host, any mechanism enhancing population admixture of the mite may be *** way that admixture can occur is when two genetically dissimilar mites coinvade a brood cell, with the progeny of the foundresses *** determined the relatedness of 393 pairs of *** foundresses,each pair collected from a single bee brood cell (n =five colonies).We used six microsatellites to identify the genotypes of mites coinvading a cell and calculated the frequency of pairs with different or the same *** found no deviation from random coinvasion,but the frequency of cells infested by mites with different genotypes was *** rate of recombination,coupled with a high transmission rate of mites,homogenized the allelic pool of mites within the apiary.

关键词： Apis mellifera host-parasite coevolution inbreeding avoidance mating behavior population genetics Varroa destructor

Mice with a heterozygous Lrp6 deletion have impaired fracture healing

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Bone Research 2016年第2期4卷 101-109页

作者： Travis A Burgers Juan f Vivanco Juraj zahatnansky Andrew J Vander Moren james J Mason Bart O Williams Center for Cancer and Cell Biology Program for Skeletal Disease and Tumor Microenvironment Van Andel Research Institute Grand Rapids MhUSA faculfad de Ingenieria y Ciencias Adolfo Ib6fiez University Vifia del Mar Chile padnos College of Engineering and Computing Grand Valley State University Grand Rapids MI USA

Bone fracture non-unions, the failure of a fracture to heal, occur in 10%-20% of fractures and are a costly and debilitating clinical problem. The Wnt/fl-catenin pathway is critical in bone development and fracture healing. Polymorphisms of linking low-density lipoprotein receptor-related protein 6 （LRP6）, a Wnt-binding receptor, have been associated with decreased bone mineral density and fragility fractures, although this remains controversial. Mice with a homozygous deletion of Lrp6 have severe skeletal abnormalities and are not viable, whereas mice with a heterozygous deletion have a combinatory effect with Lrp5 to decrease bone mineral density. As fracture healing closely models embryonic skeletal development, we investigated the process of fracture healing in mice heterozygous for Lrp6 （Lrp6~/-） and hypothesized that the heterozygous deletion of Lrp6 would impair fracture healing. Mid-diaphyseal femur fractures were induced in Lrp6~^- mice and wild-type controls （Lrp6~/~）. fractures were analyzed using micro-computed tomography （~CT） scans, biomechanical testing, and histological analysis. Lrp6~/- mice had significantly decreased stiffness and strength at 28 days post fracture （Pf） and significantly decreased BV/TV, total density, immature bone density, and mature area within the callus on day-14 and -21 Pf; they had significantly increased empty callus area at days 14 and 21 Pf. Our results demonstrate that the heterozygous deletion of Lrp6 impairs fracture healing, which suggests that Lrp6 has a role in fracture healing.

关键词： bone Mice with a heterozygous Lrp6 deletion have impaired fracture healing

Late post liver transplant protein losing enteropathy: Rare complication of incisional hernia

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World Journal of Gastroenterology 2013年第27期19卷 4409-4412页

作者： Jonathan D Evans M Thamara PR Perera CY Pal james Neuberger Darius f Mirza The Liver Unit The Queen Elizabeth Hospital

Development of oedema and hypoproteinaemia in a liver transplant recipient may be the first signs of graft dysfunction and should prompt a full assessment. We report the novel case of a patient who, years after liver transplantation developed a functional blind loop in an incisional hernia, which manifested as oedema and hypoproteinaemia secondary to protein losing enteropathy. After numerous investigations, the diagnosis was made by flurodeoxyglucose positron emmision tomography (fDG-PET) imaging. Surgical repair of the incisional hernia was followed several months later by resolution of the protein loss, and confirmed at a post operative fDG-PET scan at one year.

关键词： Protein losing enteropathies Bacterial overgrowth Hypoproteinaemia Incarcerated hernia Liver transplantation.

Sports compression garments improve resting markers of venous return and muscle blood flow in male basketball players

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Journal of Sport and Health Science 2023年第4期12卷 513-522页

作者： Shane f.O'Riordan Rod McGregor Shona L.Halson David J.Bishop james R.Broatch Institute for Health and Sport(iHeS) Victoria UniversityFootscrayVIC 3011Australia Department of Physiology Australian Institute of SportBruceACT 2617Australia faculty of Health University of CanberraBruceACT 2617Australia School of Behavioural and Health Sciences Australian Catholic UniversityBanyoQLD 4014Australia

Background:The benefits associated with sports compression garments are thought to be closely related to enhanced blood ***,findings are equivocal,possibly due to heterogeneity in the techniques used for measuring blood flow,the garment types used,and the pressures *** study combined Doppler ultrasound and near-infrared spectroscopy technologies to provide the first comprehensive assessment of the effects of 3 sports compression garment types on markers of venous return and muscle blood flow at ***:Resting lower-limb blood flow measures(markers of venous return,muscle blood flow,and muscle oxygenation)of 22 elite,junior,male basketball players(age=17.2±0.9 years,mean±SD)were assessed in 4 separate conditions:no compression(CON),compression tights(TIGHTS),compression shorts(SHORTS),and compression socks(SOCKS).Markers of venous return(cross-sectional area,time-averaged mean and peak blood flow velocity,and venous blood flow)were measured via Doppler ultrasound at the popliteal and common femoral *** blood flow and muscle oxygenation were measured in the gastrocnemius medialis and vastus lateralis using near-infrared ***:Popliteal markers of venous return were higher in TIGHTS compared to CON(pfemoral vein markers of venous return were higher for all conditions compared to CON(pflow was higher for TIGHTS compared to CON(p=0.000),SOCKS(p=0.012),and SHORTS(p=0.000),with SOCKS higher compared to SHORTS(p=0.046).Vastus lateralis blood flow was higher for TIGHTS compared to CON(p=0.028)and SOCKS(p=0.019),with SHORTS also higher compared to CON(p=0.012)and SOCKS(p=0.005).Gastrocnemius medialis oxygenation was higher for TIGHTS compared to CON(p=0.003),SOCKS(p=0.033),and SHORTS(p=0.003),with SOCKS higher compared to CON(p=0.044)and SHORTS(p=0.032).Va

关键词： Arterial perfusion Lower-limb compression Pressure Venous flow

Closed cranial window rodent model for investigating hemodynamic response to elevated intracranial pressure

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Animal Models and Experimental Medicine 2021年第4期4卷 391-397页

作者： Matt T.Oberdier james f.Antaki Alexander Kharlamov Stephen C.Jones Department of Biomedical Engineering Carnegie Mellon UniversityPittsburghPennsylvaniaUSA Department of Anesthesiology Allegheny-Singer Research InstitutePittsburghPennsylvaniaUSA

Background:Elevated intracranial pressure(ICP)occurs in several physiological and pathological conditions,yet long-term sequellae are not common,which implies that blood flow is preserved above ischemic ***:This pilot study sought to confirm this hypothesis using a closed cranial window model in a rat in which ICP was elevated to 120 mmHg for 12 min,and superficial cortical perfusion was measured by laser Doppler flowmetry and laser speckle ***:following a transient increase,cortical blood flow decreased to between 25%and 75%of *** levels correspond to disrupted metabolism and decreased protein synthesis but did not exceed thresholds for electrical signaling or membrane *** may partially explain how some episodes of elevated ICP remain ***:The closed cranial window model provides a platform for prospective study of physiologic responses to artificially elevated ICP during neurosurgery to promote hemostasis.

关键词： cerebrovascular circulation craniotomy hemodynamics hydrocephalus intracranial pressure perfusion