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Optically stimulated luminescence dating of aeolian sand in the Otindag dune field and Holocene climate change

science China Earth sciences 2008年第6期51卷 837-847页

作者： Joseph mason James sWINEHART Ronald GOBLE Department of Geography University of Wisconsin Madison school of Natural Resources IANR University of Nebraska-Lincoln Department of Geosciences University of Nebraska-Lincoln

The dune system in Otindag sand field of northern China is sensitive to climate change, where effective moisture and related vegetation cover play a controlling role for dune activity and stability. Therefore, aeolian deposits may be an archive of past environmental changes, possibly at the millennial scale, but previous studies on this topic have rarely been reported. In this study, thirty-five optically stimulated luminescence (OsL) ages of ten representative sand-paleosol profiles in Otindag sand field are ob-tained, and these ages provide a relatively complete and well-dated chronology for wet and dry varia-tions in Holocene. The results indicate that widespread dune mobilization occurred from 9.9 to 8.2 ka, suggesting a dry early Holocene climate. The dunes were mainly stabilized between 8.0 and 2.7 ka, implying a relatively wet climate, although there were short-term penetrations of dune activity during this wet period. After ~2.3 ka, the region became dry again, as inferred from widespread dune activity. The '8.2 ka' cold event and the Little Ice Age climatic deterioration are detected on the basis of the dune records and OsL ages. During the Medieval Warm Period and the sui-Tang Warm Period (570-770 AD), climate in Otindag sand field was relatively humid and the vegetation was denser, and the sand dunes were stabilized again. These aeolian records may indicate climate changes at millennial time scale during Holocene, and these climatic changes may be the teleconnection to the climate changes elsewhere in the world.

关键词： Otindag sand field OsL dating Holocene drought dune

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Field scanner design for MUsTANG of the Green Bank Telescope

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science China(Physics,Mechanics & Astronomy) 2011年第11期54卷 2091-2096页

作者： CHENG JingQuan LI Yang LI XinNan mason Brian National Radio Astronomy Observatory Charlottesville 22903 USA Nanjing Institute of Astronomical Optics and Technology Nanjing 210042 China

MUsTANG (Multiplex sQUID TEs Array at Ninety GHz) is a bolometer camera for the Green Bank Telescope (GBT) working at a frequency of 90 *** detector has a field of view of 40 *** cancel out random emission change from atmosphere and other sources,requires a fast scanning reflecting system with a few arcminute *** this paper,the aberrations of an off-axis system are *** condition for an optimized system is *** an optimized system,as additional image transfer mirrors are introduced,new aberrations of the off-axis system may be reintroduced,resulting in a limited field of *** this paper,different scanning mirror arrangements for the GBT system are analyzed through the ray tracing *** include using the subreflector as the scanning mirror,chopping a flat mirror and transferring image with an ellipse mirror,and chopping a flat mirror and transferring image with a pair of face-to-face paraboloid *** system analysis shows that chopping a flat mirror and using a well aligned pair of paraboloids can generate the required field of view for the MUsTANG detector system,while other systems all suffer from larger off-axis aberrations added by the system *** spot diagrams of the well aligned pair of paraboloids produced are only about one Airy disk size within a scanning angle of about 3 arcmin.

关键词： antenna optics off-axis linear astigmatism coma reflector scanner

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Impact of patch size on woody tree species richness and abundance in a tropical montane evergreen forest patches of south India

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Journal of Forestry Research 2018年第6期29卷 1675-1687页

作者： Dharmalingam Mohandass mason J.Campbell Priya Davidar Root and soil Biology Laboratory Department of BotanyBharathiar UniversityCoimbatoreTaminadu 641046India Centre for Tropical Environmental and sustainability science(T.E.s.s.) College of Science and EngineeringJames Cook UniversityCairnsQLD 4870Australia Department of Ecology and Environmental sciences Pondicherry UniversityKalapetPondicherry 605014India

We examined the effects of forest patch size on woody tree species richness and abundance in tropical montane evergreen forest patches of the Nilgiri region,south India. We sampled woody trees(>1 cm dbh) from 21 forest patches in the upper Nilgiri hills(> 2000 m elevation) and recorded a total of 35,146 individuals of 61 species, 45 genera and 30 families. species richness and abundance of sapling/shrubs(≥ 1 to sed significantly with increasing patch size, but the species richness and abundance of small, medium and larger trees(≥ 10 to spectively) did not. Overall, forest interior species richness and abundance increased significantly with increasing patch size but edge species richness did not. species richness and abundance of shade-tolerant and shade-demanding tree species also increased with increasing patch size. The abundance of zoochory dispersed tree species was significantly related to increasing patch size, but those dispersed by autochory did not display any clear relationship between patch size and species richness or *** findings suggest that with increasing forest patch area,tree compositional patterns may be driven by species specific shade-tolerance adaptations and dispersal *** responses in these traits by the plant community within the individual habitat zones of forest edge and interiors likely plays a major role in determining the inherent plant community and thus the subsequent ecological processes of forest patches, including their responses to increasing patch area.

关键词： Dispersal mode Forest fragments shade-tolerance species–area relationships Western Ghats

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The state of the art in scale inhibitor squeeze treatment

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Petroleum science 2020年第6期17卷 1579-1601页

作者： Amy T.Kan Zhaoyi Dai mason B.Tomson Department of Civil and Environmental Engineering Rice University6100 Main StreetHoustonTX 77005USA

The mechanistic understanding of the reactions that govern the inhibitor retention and release,modeling,and the state-ofthe-art innovation in squeeze treatment are *** retention and release are governed by(1)the amount of calcite that can dissolve prior to inhibitor-induced surface poisoning;(2)calcite surface poisoning after^20 molecular layers of surface coverage by the adsorbed inhibitors to retard further calcite dissolution;(3)less base,CO3^2-,is released into the aqueous solution;(4)formation of the more acidic inhibitor precipitates;(5)phase transformation and maturation of the more acidic inhibitor precipitates;and(6)dissolution of the less soluble crystalline inhibitor *** trend to advance squeeze technologies is through(1)enhancing scale inhibitor retention,(2)optimizing the delivery of scale inhibitors to the target zone,and(3)improving monitoring ***,a prototype yardstick for measuring the squeeze performance is used to compare the squeeze life of 17 actual squeeze *** though the various squeeze treatments appear to be *** published squeeze durations can be rated based on the normalized squeeze life per unit mass of inhibitors.

关键词： scale inhibitor squeeze Inhibitor retention surface poisoning Adsorption squeeze life

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The influence of stocking levels,clone,fertilization,and weed control on surface CO_(2)efflux in a mid-rotation Pinus radiata *** plantation in Canterbury,New Zealand

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Journal of Forestry Research 2021年第6期32卷 2567-2575页

作者： Mohan KC Euan G.mason Horacio E.Bown school of Forestry University of CanterburyPrivate Bag 4800ChristchurchNew Zealand Ministry of Industry TourismForests and EnvironmentHetaudaBagmati ProvinceNepal Faculty of Forestry University of ChileP.O.Box 9206SantiagoChile

silvicultural practices applied in managed forest plantations may help counteract the effects of climate change by influencing soil surface CO_(2)efflux(Fs).Understanding the effects of silvicultural practices on Fs will provide unbiased estimates of carbon fluxes and allow better silvicultural decisions for carbon ***,we assessed how Fs differed seasonally across silvicultural practices(i.e.,stocking levels,clone,fertilization and weed control treatments)and evaluated the effects of soil temperature(Ts)and soil volumetric water content(θv)on Fs across these practices for a mid-rotation(14 year-old)Pinus radiata plantation in the Canterbury region of New *** were significant differences in Fs(pseasons,three levels of stocking,and five *** effects of fertilization and weed control applied 12 years previously on Fs were *** estimate of Fs(mean±1 standard deviation)from the study site was 22.7±7.1 t ha^(-1)a^(-1)in the form of CO_(2)(6.2±2.1 t ha^(-1)a^(-1)in the form of C).Fs values were consistently higher in plots with 1250 stems ha^(-1)compared to 2500 stems ha^(-1),which may be related to a strong soil resource limitation because of the close spacing in the latter *** differences in Fs across clones suggest that variations in carbon partitioning might explain their growth *** treatments influenced Fs response to soil temperature(psulting in models explaining 28-49%of the total variance in *** findings provide insights into how silvicultural management decisions may impact Fs in mid-rotation radiata pine plantations,contributing towards developing more precise and unbiased plantation carbon budgets.

关键词： Clone silvicultural practices soil CO_(2)efflux stocking Weed control

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Phase behavior of rotationally asymmetric Brownian kites containing 90°internal angles

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Chinese Physics B 2021年第12期30卷 467-472页

作者： Huaqing Liu Yiwu Zong Zhanglin Hou Thomas G.mason Kun Zhao Key Laboratory of systems Bioengineering(Ministry of Education) School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Wenzhou Institute University of Chinese Academy of SciencesWenzhou 325001China Department of Physics and Astronomy University of California-Los AngelesLos AngelesCA 90095USA Department of Chemistry and Biochemistry University of California-Los AngelesLos AngelesCA 90095USA Physics Department Tianjin UniversityTianjin 300072China

Previous Monte Carlo simulations have shown that ordered tetratic phases can emerge in a dense two-dimensional Brownian system of rotationally asymmetric hard kites having 90°internal ***,there have been no experimental investigations yet to compare with these simulation ***,we have fabricated two types of micron-sized kites having internal angles of 72°-90°-108°-90°and 72°-99°-90°-99°,respectively,and we have experimentally studied their phase behavior in two-dimensional *** and in contrast to the Monte Carlo simulations,the experimental results show a phase sequence of isotropic fluid-hexagonal rotator crystal-square crystal as the area fractionφA increases for both types of *** observed square crystal displays not only a quasi-long-range translational order but also(quasi-)long-range 4-fold bond-and molecular-orientational order;these characteristics confirm that tetratic order can emerge even in dense Brownian systems of rotationally asymmetric particles.A model based on local polymorphic configurations(LPCs)is proposed to understand the origin of the square lattice order in these dense kite *** results in this study provide a new route to realize custom-designed self-assembly of colloids by controlling LPCs.

关键词： tetratic order colloidal kites two-dimentional system phase behavior

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A signal-substrate match in the substrate-borne component of a multimodal courtship display

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Current Zoology 2010年第3期56卷 370-378页

作者： Damian O.ELIAs Andrew C.mason Eileen A.HEBETs Department of Environmental science Policy and ManagementUniversity of California Integrative Behaviour and Neuroscience Group University of Toronto Scarborough school of Biological sciences University of Nebraska

The environment can impose strong limitations on the efficacy of signal transmission. In particular, for vibratory communication, the signaling environment is often extremely heterogeneous at small scales. Nevertheless, natural selection is expected to select for signals well-suited for effective transmission. Here, we test for substrate-dependent signal efficacy in the wolf spider schizocosa stridulans strattou 1991. We first explore the transmission characteristics of this important signaling mo- dality by playing recorded substrate-bome signals through three different substrates （leaf litter, pine litter, and red clay） and measuring the propagated signal. We found that the substrate-bome signal of s. stridulans attenuates the least on leaf litter, the substrate upon which the species is naturally found. Next, by assessing mating success with artificially muted and non-muted males across different signaling substrates （leaf litter, pine litter, and sand）, we explored the relationship between substrate-bome signaling and signaling substrate for mating success. We found that muted males were unsuccessful in obtaining copulations re- gardless of substrate, while mating success was dependent on the signaling substrate for non-muted males. For non-muted males, more males copulated on leaf litter than any other substrate. Taken together, these results confLrm the importance of sub- strate-bome signaling in s. stridulans and suggest a match between signal properties and signal efficacy - leaf litter transmits the signal most effectively and males are most successful in obtaining copulations on leaf litter [Current Zoology 56 （3）： 370-378, 2010].

关键词： Environmental heterogeneity sensory drive Mate choice Communication

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A New Method of Multi-scale Geologic Modeling and Display

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Journal of Earth science 2014年第3期25卷 537-543页

作者： Yongliang Bai Zhan Liu Lanfa Liu Roger mason Binghu Huang school of Geosciences China University of Petroleum Earth sciences Faculty China University of Geosciences Wuhan

A new method of multi-scale modeling and display of geologic data is introduced to provide information with appropriate detail levels for different types of research. The multi-scale display mode employs a model extending existing 2D methods into 3D space. Geologic models with different scales are organized by segmenting data into orthogonal blocks. A flow diagram illustrates an octree method for upscaling between blocks with different scales. Upscaling data from the smallest unit cells takes into account their average size and the Burgers vector when there are mismatches. A geocellular model of the Chengdao Reservoir of the shengli Oilfield, China is taken as an illustrative case, showing that the methods proposed can construct a multi-scale geologic model correctly and display data from the multi-scale model effectively in 3D.

关键词： multi-scale geologic model block data organization topological relationship upscale geologic structure multi-scale display.

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Genome and clonal hematopoiesis stability contrasts with immune,cfDNA,mitochondrial,and telomere length changes during short duration spaceflight

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Precision Clinical Medicine 2024年第1期7卷 1-13页

作者： J.sebastian Garcia-Medina Karolina sienkiewicz s.Anand Narayanan Eliah G.Overbey Kirill Grigorev Krista A.Ryon Marissa Burke Jacqueline Proszynski Braden Tierney Caleb M.schmidt Nuria Mencia-Trinchant Remi Klotz Veronica Ortiz Jonathan Foox Christopher Chin Deena Najjar Irina Matei Irenaeus Chan Carlos Cruchaga Ashley Kleinman JangKeun Kim Alexander Lucaci Conor Loy Omary Mzava Iwijn De Vlaminck Anvita singaraju Lynn E.Taylor Julian C.schmidt Michael A.schmidt Kelly Blease Juan Moreno Andrew Boddicker Junhua Zhao Bryan Lajoie Andrew Altomare semyon Kruglyak shawn Levy Min Yu Duane C.Hassane susan M.Bailey Kelly Bolton Jaime Mateus Christopher E.mason Department of Physiology and Biophysics Weill Cornell MedicineCornell UniversityNew YorkNY 10021USA The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine Weill Cornell MedicineNew YorkNY 10021USA Department of Immunology Weill Cornell MedicineCornell UniversityNew YorkNY 10021USA Department of stem Cell Biology and Regenerative Medicine Keck School of MedicineUniversity of Southern CaliforniaLos AngelesCA 90033USA space Exploration Technologies Corporation HawthomeCA 90250USA sovaris Aerospace BoulderCO 80302USA Advanced Pattern Analysis&Human Performance Group BoulderCO 80302USA Children's Cancer and Blood Foundation Laboratories Departments of Pediatrics and Cell and Developmental BiologyDrukier Institute for Children's HealthMeyer Cancer CenterWeill Cornell MedicineNew YorkNY 10021USA Meyer Cancer Center Weill Cornell MedicineNew YorkNY 10065USA Department of Nutrition and Integrative Physiology Florida State UniversityTallahasseeFL 32306USA Department of systems Engineering Colorado State UniversityFort CollinsCO 80523USA Element Biosciences San DiegoCA 10055USA Department of Environmental and Radiological Health sciences Colorado State UniversityFort CollinsCO 80523USA Cell and Molecular Biology Program Colorado State UniversityFort CollinsCO 80523USA BioAstra Inc New YorkNYUSA Washington University st Louis Oncology Division St.LouisMO 63100USA Meinig school of Biomedical Engineering Cornell UniversityIthacaNY 14853USA The Feil Family Brain and Mind Research Institute Weill Cornell MedicineNY 10021USA WorldQuant Initiative for Quantitative Prediction Weill Cornell MedicineNew YorkNY 10021USA

Background The Inspiration4(I4)mission,the first all-civilian orbital flight mission,investigated the physiological effects of short-duration spaceflight through a multi-omic *** advances,there remains much to learn about human adaptation to spaceflight's unique challenges,including microgravity,immune system perturbations,and radiation *** To provide a detailed genetics analysis of the mission,we collected dried blood spots pre-,during,and post-flight for DNA *** length was measured by quantitative PCR,while whole genome and cfDNA sequencing provided insight into genomic stability and immune adaptations.A robust bioinformatic pipeline was used for data analysis,including variant calling to assess mutational *** Telomere elongation occurred during spaceflight and shortened after return to ***-free DNA analysis revealed increased immune cell signatures *** significant clonal hematopoiesis of indeterminate potential(CHIP)or whole-genome instability was *** long-term gene expression changes across immune cells suggested cellular adaptations to the space environment persisting months *** Our findings provide valuable insights into the physiological consequences of short-duration spaceflight,with telomere dynamics and immune cell gene expression adapting to spaceflight and persisting after return to *** sequencing data will serve as a reference point for studying the early development of CHIP in astronauts,an understudied phenomenon as previous studies have focused on career *** study will serve as a reference point for future commercial and non-commercial spaceflight,low Earth orbit(LEO)missions,and deep-space exploration.

关键词： genomes clonal hematopoiesis stability immune mitochondria ribosomes spaceflight

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subterranean Origin of Accreted Lapilli in Cone-sheets of the Houshihushan sub-Volcanic Ring Complex, shanhaiguan, China

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Journal of Earth science 2015年第5期26卷 661-668页

作者： Xia Wen Changqian Ma Roger mason Longkang sang Junming Zhao school of Nuclear Resources Engineering University of South China state Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences school of Earth sciences China University of Geosciences

In addition to syenite ring dykes and multiple alkaline granite stocks, the sub-volcanic Houshihushan alkaline ring complex near shanhaiguan, Qinhuangdao City, contains cone-sheets of two types： a majority filled with granite porphyry and a minority filled with quartz syenite porphyry. Many cone sheets show evidence of multiple magma intrusion events. some granite porphyry sheets＇ multiple chilled margins display magmatic roll structures indicating that turbulent magma flowed up the fractures. In one upward-closing cone-sheet K-feldspar phenocrysts floated up through fluid granite porphyry magma and became concentrated at the top providing direct evidence of shallow-level crystal fractionation, confirmed by published rock analyses. Accreted lapilli with K-feldspar crystal cores occur only in the inner parts of a minority of cone-sheets and field relationships indicate that they must have formed beneath the ground surface. similar lapilli occur in erupted ignimbrites preserved in the collapsed caldera. Voids between lapilli in cone-sheets indicate the presence of volumes of gas below the surface that could have flowed upwards as fast-moving hot gas streams. We propose a mechanism of formation that began with subterranean magmatic rolls with K-feldspar crystal cores that formed on dyke walls, and became detached. Then they were caught up in rising gas streams and erupted at the surface. Thus accreted lapilli formed underground, were erupted along with blobs of fluid glass in escaping gases, and transported over the surface in nuées ardentes, to settle and cool as ignimbrite flows.

关键词： accreted lapilli cone-sheets alkaline ring complex K-feldspar fractionation ignimbrite Houshihushan alkaline ring complex

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