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Science China Materials 2023年第7期66卷 2947-2948页

作者： nicholas Adams Guozhong Cao Department of Materials Science and Engineering University of WashingtonSeattleWA 98195-2120USA

Organic-inorganic hybrid perovskites possess a unique combination of excellent electronic and photoelectrochemical properties that can be readily tailored by partial or complete substitution of their constituent elements owing to their nonclose packing anion lattice[1,2].Perovskite solar cells(PSCs)employing hybrid perovskites as an active layer have seen rapid improvements and have achieved high power conversion efficiencies(PCEs)now exceeding 25%[2].

关键词： perovskite exceeding layer

Intrusions of the Panxi region,China,and their magmatic ore deposits

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Geoscience Frontiers 2013年第5期4卷 479-480页

作者： nicholas Arndt ISTerre Universite Joseph Fourier38400 St Martin d'HeresFrance

The intrusions of the Panzhihua-Xichang（Panxi） region in southwest China have become well known in the past decade because they host large and rich magmatic oxide deposits that are mined for Fe,Ti and *** intrusions form part of the Emeishan large igneous province（ELIP）,which is commonly believed to be the product of melting in a mantle *** ELIP was emplaced about 260 Ma ago,at the same time as the end-Guadalupian mass *** investigation of the Panxi intrusions therefore provides information relevant to three broad areas of the earth sciences：（1）the petrogenesis of mafic magmas,

关键词： Intrusions magmatic nicholas

The Realization Problem for Discrete Morse Functions on Trees

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Algebra Colloquium 2020年第3期27卷 455-468页

作者： Yuqing Liu nicholas A.Scoville Department of Mathematics and Computer Science Ursinus College CollegevillePA 19426USA

We introduce a new notion of equivalence of discrete Morse functions on graphs called persistence *** functions are considered persistence equivalent if and only if they induce the same persistence *** compare this notion of equivalence to other notions of equivalent discrete Morse *** we compute an upper bound for the number of persistence equivalent discrete Morse functions on a fixed graph and show that this upper bound is sharp in the case where our graph is a *** is a version of the"realization problem"of the persistence *** conclude with an example illustrating our construction.

关键词： persistent homology barcode discrete Morse theory tree

Authentic synthetic nacre

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National Science Review 2017年第3期4卷 284-285页

作者： nicholas Kotov MSE Department at the University of Michigan

Shining pearls and colorful seashells are attractive gifts from ***,some materials scientists are attracted primarily to their main component,nacre,also known as mother of ***’s combination of high strength

关键词： of in Ca CO that Authentic synthetic nacre is high

Round Top Mountain rhyolite(Texas, USA), a massive, unique Y-bearing-fluorite-hosted heavy rare earth element(HREE) deposit

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Journal of Rare Earths 2014年第1期32卷 90-96页

作者： PINGITORE nicholas CLAGUE Juan GORSKI Daniel Department of Geological Sciences The University of Texas at El Paso Texas Rare Earth Resources

Round Top Mountain in Hudspeth County, west Texas, USA is a surface-exposed rhyolite intrusion enriched in Y and heavy rare earth elements （HREEs）, as well as Nb, Ta, Be, Li, F, Sn, Rb, Th, and U. The massive tonnage, estimated at well over 1 billion tons, of the deposit makes it a target for recovery of valuable yttrium and HREEs （YHREEs）, and possibly other scarce ele-ments. Because of the extremely fine grain size of the mineralized rhyolite matrix, it has not been clear which minerals host the YHREEs and in what proportions. REE-bearing minerals reported in the deposit included bastn？site-Ce, Y-bearing fluorite, xeno-time-Y, zircon, aeschynite-Ce, a Ca-Th-Pb fluoride, and possibly ancylite-La and cerianite-Ce. Extended X-ray absorption fine struc-ture （EXAFS） indicated that virtually all of the yttrium, a proxy for the HREEs, resided in a coordination in the fluorite-type crystal structure, rather than those in the structures of bastn？site-Ce and xenotime-Y. The YREE grade of the Round Top deposit was just over 0.05%, with 72%of this consisting of YHREEs. This grade was in the range of the South China ionic clay deposits that supply essentially all of the world’s YHREEs. Because the host Y-bearing fluorite is soluble in dilute sulfuric acid at room temperature, a heap leaching of the deposit appeared feasible, aided by the fact that 90%-95%of the rock consists of unreactive and insoluble feld-spars and quartz. The absence of overburden, remarkable consistency of mineralization grade throughout the massive rhyolite, prox-imity （a few km） to a US interstate highway, major rail systems and gas and electricity, temperate climate, and stable political location in the world’s largest economy all enhanced the potential economic appeal of Round Top.

关键词： heavy rare earth elements yttrium-beating fluorite yttrofluorite heap leaching rhyolite Round Top deposit

Arbuscular mycorrhizal fungi are necessary for the induced response to herbivores by Cucumis sativus

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Journal of Plant Ecology 2013年第2期6卷 171-176页

作者： nicholas A.Barber Department of Biological Sciences Northern Illinois UniversityDeKalbIL 60115USA

Aims Although ecological interactions are often conceptualized and stud-ied in a pairwise framework,ecologists recognize that the outcomes of these interactions are influenced by other members of the ***(i)between plants and insect herbivores and(I)between plants and mycorrhizal fungi are ubiquitous in terrestrial ecosystems and may be linked via common host *** studies suggest that colonization by arbuscular mycorrhizal fungi(AMF)can modifty plants'induced responses to herbivore attack,but these indirect effects of fungal symbionts are poorly understood.I investigated the role of AMF in induced plant response to a gen-eralist ***|manipulated AMF status and herbivory in Cucumis sativus L.(cucumber,Cucurbitaceae)in a greenhouse to investigate induced responses in the presence and absence of the mycorrhi-zal fungus Glomus intraradices(Glomeraceae).Spodoptera exigua Habner(Noctuidae)were used to manipulate prior damage and later as assay caterpillars.I also measured *** and her-bivory effects on plant N and effects on plant *** tant Findings AMF status affected the induced response of ***,underscor-ing the importance of incorporating the roles of plant symbionts into plant defense *** caterpillars ate significantly more leaf tissue only on mycorrhizal plants that had experienced prior *** more consumption,biomass change in these cat-erpillars did not differ from those feeding on plants with other treat-ment *** N content was reduced by *** but unaffected by herbivory treatments,suggesting that the observed differences in assay caterpillar feeding were due to changes in defensive chemistry that depended on AMF.

关键词： aboveground-belowground cucurbitacin induced defense mutualist resistance trait-mediated indirect effect

Influence of random heterogeneity of shear wave velocity on sliding mass response and seismic deformations of earth slopes

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Earthquake Engineering and Engineering Vibration 2020年第2期19卷 269-287页

作者： Pourya Kazemi Esfeh Bahram Nadi nicholas Fantuzzi Department of Civil ChemicalEnvironmentaland Materials EngineeringUniversity of BolognaItaly Department of Civil Engineering Azad University of NajafabadIran

Soil shear wave velocity has been recognized as a governing parameter in the assessment of the seismic response of *** spatial variability of soil shear wave velocity can influence the seismic response of sliding mass and seismic ***,most analyses of sliding mass response have been carried out by deterministic *** paper stochastically investigates the effect of random heterogeneity of shear wave velocity of soil on the dynamic response of sliding mass using the correlation matrix decomposition method and Monte Carlo simulation(MCS).The software FLAC 7.0 along with a Matlab code has been utilized for this *** influence of statistical parameters on the seismic response of sliding mass and seismic displacements in earth slopes with different inclinations and stiffnesses subject to various earthquake shakings was *** results indicated that,in general,the random heterogeneity of soil shear modulus can have a notable impact on the sliding mass response and that neglecting this phenomenon could lead to underestimation of sliding deformations.

关键词： random heterogeneity random fields Monte Carlo simulation sliding mass response seismic deformations

Heart healthy equals prostate healthy and statins, aspirin, and/or metformin （S.A.M.） are the ideal recommendations for prostate cancer prevention

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Asian Journal of Andrology 2015年第5期17卷 783-791,I0008页

作者： Mark A Moyad nicholas J Vogelzang Department of Urology University of Michigan Medical Center Ann Arbor Michigan USA Developmental Therapeutics Committee and Genitourinary Committee for US Oncology Research Comprehensive Cancer Centers of Nevada Las Vegas Nevada USA

Cardiovascular disease （CVD） has been the number one cause of death in the U.S. for 114 of the last 115 years. Lifestyle factors that promote CVD also appear to increase prostate cancer risk and those that reduce CVD risk also appear to reduce the risk of prostate cancer. The largest randomized trials utilizing dietary supplements or pharmacologic agents for prostate cancer prevention （Selenium and Vitamin E Cancer Prevention Trial [SELECT]） have also shed light on the problems and future solutions in this area. Dietary supplements that have not been found to be CVD protective, such as selenium and Vitamin E have not been found to be prostate protective. In addition, over exposure to specific anti-oxidants in nutritionally replete populations may be encouraging cancer growth. Futuretrials of dietary supplements to prevent prostate cancer could be problematic because by the time a definitive trial is initiated the participants will no longer be ＂deficient＂ in the nutrient being tested, which arguably occurred in the SELECT trial. It is also interesting that statins, aspirin, and/or metformin （S.A.M.） are 3 generic, low-cost, heart healthy agents derived from natural sources with separate mechanism of actions, which all appear to have the best benefit to risk ratio compared to any other agent available for prostate cancer prevention, especially aggressive disease, or as an ancillary agent （s） to conventional cancer treatment. It is time to focus on the forest over the trees and recommend proven CVD protective measures for men concerned about their risk of prostate cancer.

关键词： aspirin diet lifestyle metformin prostate cancer statins

Articulating China's Science and Technology:Knowledge Collaboration Networks Within and Beyond the Yangtze River Delta Megalopolis in China

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Chinese Geographical Science 2018年第2期28卷 247-260页

作者： LI Yingcheng nicholas A.PHELPS School of Architecture Southeast University Bartlett School of Planning University College London

In this paper, we reconsider the defining but often overlooked ‘hinge' function of megalopolises by analyzing how megalopolises have articulated national and international urban systems in the context of a globalizing knowledge economy. Taking the case of China's Yangtze River Delta(YRD) region, we particularly focus on knowledge circulation within and beyond the YRD region by analyzing the pattern and process of knowledge collaboration at different geographical scales during the 2004–2014 period. Results show that the structure of scientific knowledge collaboration as reflected by co-publications has been strongest at the national scale whereas that of technological knowledge collaboration as measured by co-patents has been strongest at the global scale. Despite this difference, the structure of both scientific and technological knowledge collaboration has been functionally polycentric at the megalopolitan scale but become less so at the national and global scales. The ‘globally connected but locally disconnected' pattern of Shanghai's external knowledge collaboration suggests that the gateway role of the YRD megalopolis in promoting knowledge collaboration at different geographical scales will take time before it is fully realized.

关键词： urban network publication patent scale gateway Yangtze River Delta (YRD)

Purines:From Diagnostic Biomarkers to Therapeutic Agents in Brain Injury

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Neuroscience Bulletin 2020年第11期36卷 1315-1326页

作者： Bruno G.Frenguelli nicholas Dale School of Life Sciences The University WarwickCoventry CV47ALUK

The purines constitute a family of inter-related compounds that serve a broad range of important intracellular and extracellular biological *** particular,adenosine triphosphate(ATP)and its metabolite and precursor,adenosine,regulate a wide variety of cellular and systems-level physiological processes extending from ATP acting as the cellular energy currency,to the adenosine arising from the depletion of cellular ATP and responding to reduce energy demand and hence to preserve ATP during times of metabolic *** inter-relationship provides opportunities for both the diagnosis of energy depletion during conditions such as stroke,and the replenishment of ATP after such *** this review we address these opportunities and the broad potential of purines as diagnostics and restorative agents.

关键词： Purines Adenosine ATP Biomarker Stroke Cerebral ischemia Traumatic brain injury Adenine D-ribose