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Detailed characterization of kHz-rate laser-driven fusion at a thin liquid sheet with a neutron detection suite

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High Power Laser Science and Engineering 2024年第1期12卷 13-23页

作者： Benjamin M.Knight Connor M.Gautam Colton R.Stoner Bryan V.Egner joseph R.Smith chris M.Orban juan j.Manfredi Kyle D.Frische Michael L.Dexter Enam A.Chowdhury Anil K.Patnaik Department of Engineering Physics Air Force Institute of TechnologyWPAFBOHUSA Physics Department Marietta CollegeMariettaOHUSA Department of Physics The Ohio State UniversityColumbusOHUSA Department of Materials Science and Engineering and Department of Electrical and Computer ScienceThe Ohio State UniversityColumbusOHUSA Intense Energy Solutions LLCPlain CityOHUSA

We present detailed characterization of laser-driven fusion and neutron production(-10^(5)/second) using 8 mj, 40 fs laser pulses on a thin(<1 μm) D_2O liquid sheet employing a measurement suite. At relativistic inte... 详细信息

We present detailed characterization of laser-driven fusion and neutron production(-10^(5)/second) using 8 mj, 40 fs laser pulses on a thin(j-309 organic scintillator with pulse-shape discrimination, a ~3He proportional counter and a set of 36 bubble detectors. Time-of-flight analysis of the scintillator data shows the energy of the produced neutrons to be consistent with 2.45 MeV. Particle-in-cell simulations using the WarpX code support significant neutron production from D-D fusion events in the laser±target interaction region. This high-repetition-rate laser-driven neutron source could provide a low-cost, on-demand test bed for radiation hardening and imaging applications.

关键词： high-repetition-rate laser-driven fusion laser-plasma interaction liquid target neutron detectors

Adapting the botanical landscape of Melbourne Gardens(Royal Botanic Gardens Victoria)in response to climate change

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Plant Diversity 2017年第6期39卷 338-347页

作者： Timothy j.Entwisle chris Cole Peter Symes Royal Botanic Gardens Victoria

Botanic gardens around the world maintain collections of living plants for science, conservation, education, beauty and more. These collections change over time-in scope and content-but the predicted impacts of climate change will require a more strategic approach to the succession of plant species and their landscapes. Royal Botanic Gardens Victoria has recently published a 'Landscape Succession Strategy'for its Melbourne Gardens, a spectacular botanical landscape established in 1846. The strategy recognizes that with 1.6 million visitors each year, responsibility for a heritage-listed landscape and the need to care for a collection of 8500 plant species of conservation and scientific importance, planting and planning must take into account anticipated changes to rainfall and temperature. The trees we plant today must be suitable for the climate of the twenty-second century. Specifically, the Strategy sets out the steps needed over the next twenty years to transition the botanic garden to one resilient to the climate modelled for2090. The document includes a range of practical measures and achievable(and at times somewhat aspirational) targets. Climate analogues will be used to identify places in Australia and elsewhere with conditions today similar to those predicted for Melbourne in 2090, to help select new species for the collection. Modelling of the natural and cultivated distribution of species will be used to help select suitable growth forms to replace existing species of high value or interest. Improved understanding of temperature gradients within the botanic garden, water holding capacity of soils and plant water use behaviour is already resulting in better targeted planting and irrigation. The goal is to retain a similar diversity of species but transition the collection so that by 2036 at least 75% of the species are suitable for the climate in 2090. Over the next few years we hope to provide 100% of irrigation water from sustainable water sources, and

关键词： Climate change Landscape succession Botanic garden Uving collection

State of the art of friction modelling at interfaces subjected to elastohydrodynamic lubrication(EHL)

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Friction 2021年第2期9卷 207-227页

作者： Zhuming BI Donald W.MUELLER chris W.j.ZHANG Civil and Mechanical Engineering Purdue University Fort WayneIN 46805USA Department of Mechanical Engineering University of SaskatchewanSaskatoon SK S7N 5A9Canada

Elastohydrodynamic lubrication(EHL)is a type of fluid-film lubrication where hydrodynamic behaviors at contact surfaces are affected by both elastic deformation of surfaces and lubricant *** of contact interfaces under EHL is challenging due to high nonlinearity,complexity,and the multi-disciplinary *** paper aims to understand the state of the art of computational modelling of EHL by(1)examining the literature on modeling of contact surfaces under boundary and mixed lubricated conditions,(2)emphasizing the methods on the friction prediction occurring to contact surfaces,and(3)exploring the feasibility of using commercially available software tools(especially,Simulia/Abaqus)to predict the friction and wear at contact surfaces of objects with relative reciprocating motions.

关键词： elastohydrodynamic lubrication(EHL) lubricant rheology finite element analysis(FEA) friction prediction Simulia/Abaqus surface roughness coefficient of friction(CoF)

Estimation of premature forests in Georgia (USA) using *** Service FIA data and Landsat imagery

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journal of Forestry Research 2017年第6期28卷 1241-1252页

作者： Hojung Kim chris j. Cieszewski Roger C. Lowe Warnell School of Forestry and Natural Resources University of Georgia 180 E. Green Street AthensGA 30602 USA

We used geographic information system applications and statistical analyses to classify young, premature forest areas in southeastern Georgia using combined data from Landsat TM 5 satellite imagery and ground inventory data. We defined premature stands as forests with trees up to 15 years old. We estimated the premature forest areas using three methods: maximum likelihood classification(MLC), regression analysis, and k-nearest neighbor(k NN)modeling. Overall accuracy(OA) of classifying the premature forest using MLC was 82% and the Kappa coefficient of agreement was 0.63, which was the highest among the methods that we have tested. The k NN approach ranked second in accuracy with OA of 61% and a Kappa coefficient of agreement of 0.22. Regression analysis yielded an OA of 57% and a Kappa coefficient of 0.14. We conclude that Landsat imagery can be effectively used for estimating premature forest areas in combination with image processing classifiers such as MLC.

关键词： Landsat Maximum likelihood classification Regression analysis k-nearest neighbor

Planting position and shade enhance native seedling performance in forest restoration for an endangered malagasy plant

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Plant Diversity 2019年第2期41卷 118-123页

作者： Cyprien Miandrimanana j.Leighton Reid Tahiry Rivoharison chris Birkinshaw Missouri Botanical Garden Madagascar Research and Conservation Program Center for Conservation and Sustainable Development Missouri Botanical Garden

The critically endangered tree Schizolaena tampoketsana is confined to a few diminished and degraded forest fragments on the Malagasy highlands. This habitat is vulnerable to loss due to frequent fires in the surrounding grassland that threaten to spread into the forest. One of these fragments is the focus a conservation project and here the managers aim to conserve S. tampoketsana by restoring its forest habitat to its former extent as evidenced by remnant woody plants. To inform this activity the survival and early-stage growth of seedlings of four locally native tree species were compared under contrasting conditions of proximity to the remaining forest and shade. After 12 months, seedlings of three species(Baronia taratana, Eugenia pluricymosa, Uapaca densifolia) survived better and experienced improved growth in height in grassland close to the existing forest rather than distant from it, and two survived better with shade rather than unshaded. A number of mechanisms could explain these results including reduced exposure to desiccating sunlight and winds and better soil and greater water availability close to the forest. The seedlings of one species(Nuxia capitata) survived well under all conditions. This study suggests that reforestation in these dry highlands is most feasible adjacent to remnant forest fragments and in microhabitats that minimize water loss, though young plants of some tree species may be capable of surviving in harsher conditions.

关键词： Grassland Fire Forest restoration Local environment Schizolaena tampoketsana

Expression of the human TSPY gene in the brains of transgenic mice suggests a potential role of this Y chromosome gene in neural functions

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journal of Genetics and Genomics 2011年第5期38卷 181-191页

作者： Tatsuo Kido Stephanie Schubert jrg Schmidtke Yun-Fai chris Lau Division of Cell and Developmental Genetics Department of MedicineVA Medical Centerand Institute for Human GeneticsUniversity of California Institute of Human Genetics Hannover Medical School

The testis specific protein Y-encoded （TSPY） is a member of TSPY/SET/NAP1 superfamily, encoded within the gonadoblastoma locus on the Y chromosome. TSPY shares a highly conserved SET/NAP-domain responsible for protein--protein interaction among TSPY/SET/NAP 1 proteins. Accumulating data, so far, support the role of TSPYas the gonadoblastoma gene, involved in germ cell tumorigenesis. The X-chromosome homolog of TSPY, TSPX is expressed in various tissues at both fetal and adult stages, including the brain, and is capable of interacting with the multi-domain adapter protein CASK, thereby influencing the synaptic and transcriptional functions and developmental regulation of CASK in the brain and other neural tissues. Similar to TSPX, we demonstrated that TSPY could interact with CASK at its SET/NAP-domain in cultured cells. Transgenic mice harboring a human TSPYgene and flanking sequences showed specific expression of the human TSPYtransgene in both testis and brain. The neural expression pattern of the human TSPYgene overlapped with those of the endogenous mouse Cask and Tspx gene. Similarly with TSPX, TSPY was co-localized with CASK in neuronal axon fibers in the brain, suggesting a potential role（s） of TSPY in development and/or physiology of the nervous system.

关键词： TSPY TSPX CASK Y chromosome Neuron Testis

The occurrence,inheritance,and segregation of complex genomic structural variation in synthetic Brassica napus

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The Crop journal 2024年第2期12卷 515-528页

作者： Dandan Hu jin Lu Wenwen Li Yinghui Yang junxiong Xu Han Qin Hao Wang Yan Niu Huaiqi Zhang Qingqing Liu Xiangxiang He Annaliese S.Mason jchris Pires Zhiyong Xiong jun Zou National Key Laboratory of Crop Genetic Improvement College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhan 430070HubeiChina College of Agronomy Henan Agricultural UniversityZhengzhou 450002HenanChina Key Laboratory of Herbage and Endemic Crop Biotechnology Inner Mongolia UniversityHohhot 010070Inner MongoliaChina Plant Breeding Department University of BonnBonn 53115Germany Department of Soil and Crop Sciences Colorado State UniversityFort CollinsCO 80523USA

"Synthetic"allopolyploids recreated by interspecific hybridization play an important role in providing novel genomic variation for crop *** synthetic allopolyploids often undergo rapid genomic structural variation(SV).However,how such SV arises,is inherited and fixed,and how it affects important traits,has rarely been comprehensively and quantitively studied in advanced generation synthetic lines.A better understanding of these processes will aid breeders in knowing how to best utilize synthetic allopolyploids in breeding ***,we analyzed three genetic mapping populations(735 DH lines)derived from crosses between advanced synthetic and conventional Brassica napus(rapeseed)lines,using whole-genome sequencing to determine genome *** observed high tolerance of large structural variants,particularly toward the telomeres,and preferential selection for balanced homoeologous exchanges(duplication/deletion events between the A and C genomes resulting in retention of gene/chromosome dosage between homoeologous chromosome pairs),including stable events involving whole chromosomes("pseudoeuploidy").Given the experimental design(all three populations shared a common parent),we were able to observe that parental SV was regularly inherited,showed genetic hitchhiking effects on segregation,and was one of the major factors inducing adjacent novel and larger ***,novel SV occurred at low frequencies with no significant impacts on observed fertility and yield-related traits in the advanced generation synthetic ***,incorporating genome-wide SV in linkage mapping explained significantly more genetic variance for *** results provide a framework for detecting and understanding the occurrence and inheritance of genomic SV in breeding programs,and support the use of synthetic parents as an important source of novel trait variation.

关键词： Allopolyploid Large Genome structural variation Linkage mapping Synthetic polyploids Inheritance and segregation

From Slater to Mott physics by epitaxially engineering electronic correlations in oxide interfaces

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npj Computational Materials 2021年第1期7卷 846-851页

作者： Carla Lupo Evan Sheridan Edoardo Fertitta David Dubbink chris j.Pickard Cedric Weber Theory and Simulation of Condensed Matter King’s College LondonLondonUK Happy Electron Ltd LondonUK Department of Materials Science and Metallurgy University of CambridgeCambridgeUK Advanced Institute for Materials Research Tohoku UniversitySendaiJapan

Using spin-assisted ab initio random structure searches,we explore an exhaustive quantum phase diagram of archetypal interfaced Mott insulators,***-iron and lanthanum-titanium *** particular,we report that the charge transfer induced by the interfacial electronic reconstruction stabilises a high-spin ferrous Fe2+*** provide a pathway to control the strength of correlation in this electronic state by tuning the epitaxial strain,yielding a manifold of quantum electronic phases,***-Hubbard,charge transfer and Slater insulating ***,we report that the electronic correlations are closely related to the structural oxygen octahedral rotations,whose control is able to stabilise the low-spin state of Fe2+at low pressure previously observed only under the extreme high pressure conditions in the Earth’s lower ***,we provide avenues for magnetic switching via THz radiations which have crucial implications for next generation of spintronics technologies.

关键词： Slater lanthanum quantum

Revealing and exploiting hierarchical material structure through complex atomic networks

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npj Computational Materials 2017年第1期3卷 163-170页

作者： Sebastian E.Ahnert William P.Grant chris j.Pickard Theory of Condensed Matter Group Cavendish LaboratoryUniversity of CambridgeJJ Thomson AvenueCambridge CB30HEUK Sainsbury Laboratory University of CambridgeBateman StreetCambridge CB21LRUK Department of Materials Science&Metallurgy University of Cambridge27 Charles Babbage RoadCambridge CB30FSUK Advanced Institute for Materials Research Tohoku University 2-1-1 KatahiraAobaSendai 980-8577Japan

One of the great challenges of modern science is to faithfully model,and understand,matter at a wide range of *** with atoms,the vastness of the space of possible configurations poses a formidable challenge to any simulation of complex atomic and molecular *** introduce a computational method to reduce the complexity of atomic configuration space by systematically recognising hierarchical levels of atomic structure,and identifying the individual *** a list of atomic coordinates,a network is generated based on the distances between the *** the technique of modularity optimisation,the network is decomposed into *** procedure can be performed at different resolution levels,leading to a decomposition of the system at different scales,from which hierarchical structure can be *** considering the amount of information required to represent a given modular decomposition we can furthermore find the most succinct descriptions of a given atomic *** straightforward,automatic and general approach is applied to complex crystal *** show that modular decomposition of these structures considerably simplifies configuration space,which in turn can be used in discovery of novel crystal structures,and opens up a pathway towards accelerated molecular dynamics of complex atomic *** power of this approach is demonstrated by the identification of a possible allotrope of boron containing 56 atoms in the primitive unit cell,which we uncover using an accelerated structure search,based on a modular decomposition of a known dense phase of boron,γ-B_(28).

关键词： structure atomic complex