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Quantitative study on pollen-based reconstructions of vegetation history from central Canada

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Science China Earth Sciences 2008年第8期51卷 1081-1088页

作者： hart Catherina VETTER Mary SAUCHYn David Department of Biology University of ReginaS4S 0A2Canada Prairie Adaptation Research Collaborative SK S4S 7J7Canada Department of GeographyUniversity of ReginaS4S 0A2Canada

Based on high-resolution pollen records from lake cores in central Canada, the present study instructed pollen taxa assignations in ecosystem groups and modern analogue technique, reported major results of quantitativ... 详细信息

关键词： sedimentary pollen surface pollen modern analogue technique ecosystem paleovegetation past 1000 years

Oxygen-deficient bismuth tungstate and bismuth oxide composite photoanode with improved photostability

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Science Bulletin 2018年第15期63卷 990-996页

作者： Hoi Ying Chung Weijian Chen Xiaoming Wen Judy n. hart Hao Wu Yuekun Lai Rose Amal Yun Hau ng Particles and Catalysis Research Croup School of Chemical Engineering The University of New South Wales (UNSW) Sydney NSW 2052 Australia School of Photovoltaic and Renewable Energy Engineering The University of New South Wales (UNSW) Sydney NSW 2052 Australia Centre for Micro-Photonics Faculty of Science Engineering and Technology Swinburne University of Technology Melbourne VIC 2122 Australia School of Materials Science and Engineering The University of New South Wales (UNSW) Sydney NSW 2052 Australia national Engineering Laboratory for Modern Silk College of Textile and Clothing Engineering Soochow University Suzhou 215123 China

A homogeneous layer of Bi_2O_3-Bi_(14)WO_(24) composite(BWO/Bi_2O_3) thin film was fabricated using a combination of electrodeposition and thermal treatment. The evenly distributed Bi14 WO24 component within the Bi_2O_3 layer was found to be important in stabilising the photoelectrochemical performances of Bi_2O_3 photoanode by promoting the photoelectron transport. The unmodified Bi_2O_3 suffered from severe photocorrosion as proven by X-ray diffraction(XRD) and inductively coupled plasma(ICP) analyses while the composite thin film was active without noticeable activity decay for at least 3 h of illumination. This strategy might be applicable to other photocatalysts with stability issues.

关键词： Bismuth oxide Bismuth tungstate Photocorrosion

Genetic variation amongst biotypes of Dactylopius tomentosus

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Insect Science 2015年第3期22卷 360-374页

作者： Catherine W. Mathenge Markus Riegler G. Andrew C. Beattie Robert n. Spooner-hart Paul Holford School of Science and Health University of Western Sydney (Hawkesbury Campus) Hawkesbury Institute for the Environment University of Western Sydney Locked Bag 1797 Penrith NSW 2751 Australia

The tomentose cochineal scale insect, Dactylopius tomentosus （Lamarck）（Hemiptera： Dactylopiidae）, is an important biological control agent against invasive species of Cylindropuntia （Caryophyllales： Cactaceae）. Recent studies have demonstrated that this scale is composed of host-affiliated biotypes with differential host specificity and fitness on particular host species. We investigated genetic variation and phylogenetic rela-tionships among D. tomentosus biotypes and provenances to examine the possibility that genetic diversity may be related to their host-use pattern, and whether their phylogenetic relationships would give insights into taxonomic relatedness of their host plants. nucleotide sequence comparison was accomplished using sequences of the mitochondrial cytochrome c oxidase I （COI） gene. Sequences of individuals from the same host plant within a region were identical and characterized by a unique haplotype. Individuals belonging to the same biotype but from different regions had similar haplotypes. However, haplotypes were not shared between different biotypes. Phylogenetic analysis grouped the monophyletic D. tomentosus into 3 well-resolved clades of biotypes. The phylogenetic relationships and clustering of biotypes corresponded with known taxonomic relatedness of their hosts. Two biotypes, Fulgida and Mamillata, tested positive for Wolbachia （α-Proteobacteria）, a common endosymbiont of insects. The Wolbachia sequences were serendipitously detected by using insect-specific COI DnA barcoding primers and are most similar to Wolbachia Supergroup F strains. This study is the first molecular characterization of cochineal biotypes that, together with Wolbachia sequences, contribute to the better identification of the biotypes of cochineal insects and to the biological control of cacti using host-specific biotypes of the scale.

关键词： biotypes Cylindropuntia spp. Dactylopiidae Hemiptera tomentose cochineal scale Wolbachia spp.

Trace Elements and Sr, nd Isotope Geochemistry of the Lajimiao norite-Gabbro from the north Qinling Belt

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Acta Geologica Sinica(English Edition) 1994年第2期68卷 137-151页

作者： S.R.hart Department of Geology and Geopphysics Woods Hole Oceanographic InstituteWoods

The Lajimiao norite-gabbro complex, as a part of the ophiolites on the southern side of the north Qinling belt, consists of gabbro and norite-gabbro. They were derived from different magma series: the gabbro was derived from tholeiitic magma series with higher TiO2, REE abundance and Fe3+/Fe2+ ratio ; norite-gabbro was derived from calc-alkali magma series with lower TiO2, Fe3+/Fe2+ ratio and REE abundance and much lower HREE abundance, which suggests that the source of the norite-gabbro magma was deeper and controlled by eclogite facies. Geochemical characteristics of both plutonic rocks are similar to those of island-arc basalts, such as relatively high contents of Ba, Pb and Sr and relatively low contents of nb, Zr and n *** Sr, nd isotopic characteristics of the Lajimiao norite-gabbro complex are similar to those of ophiolites. Its εnd values are constant, about+2; whereas εst values have wide variation from - 6.4 to +31.2 and positively correlate with na2O, H2O+ and CO2 contents and the Fe3+/Fe2+ ratio. The εnd- nd/Th, εnd- La/nb and εnd-Ba/nb diagrams clearly show that there were significant components of terrigenous sediments in the mantle source of the Lajimiao norite-gabbro complex. It suggests that large amount of sediments had been carried into the mantle by the subducted ancient Qinling sea plate during the Palaeozoic.

关键词： trace element Sr/nd isotopes norite-gabbro Lajimiao north Qinling

California Simulation of Evapotranspiration of Applied Water and Agricultural Energy Use in California

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Journal of Integrative Agriculture 2013年第8期12卷 1371-1388页

作者： Morteza n Orang Richard L Snyder Shu Geng Quinn J hart Sara Sarreshteh Matthias Falk Dylan Beaudette Scott Hayes Simon Eching California Department of Water Resources Department of Land Air and Water ResourcesUniversity of California School of Environment and Energy Shenzhen Graduate SchoolPeking University

The California Simulation of Evapotranspiration of Applied Water （CaI-SIMETAW） model is a new tool developed by the California Department of Water Resources and the University of California, Davis to perform daily soil water balance and determine crop evapotranspiration （ETo）, evapotranspiration of applied water （ETaw）, and applied water （AW） for use in California water resources planning. ETaw is a seasonal estimate of the water needed to irrigate a crop assuming 100% irrigation efficiency. The model accounts for soils, crop coefficients, rooting depths, seepage, etc. that influence crop water balance. It provides spatial soil and climate information and it uses historical crop and land-use category information to provide seasonal water balance estimates by combinations of detailed analysis unit and county （DAU/County） over Califomia. The result is a large data base of ETc and ETaw that will be used to update information in the new California Water Plan （CWP）. The application uses the daily climate data, i.e., maximum （Tx） and minimum （Tn） temperature and precipitation （Pcp）, which were derived from monthly USDA-nRCS PRISM data （PRISM Group 2011） and daily US national Climate Data Center （nCDC） climate station data to cover California on a 4 kmx4 km change grid spacing. The application uses daily weather data to determine reference evapotranspiration （ETo）, using the Hargreaves-Samani （HS） equation （Hargreaves and Samani 1982, 1985）. Because the HS equation is based on temperature only, ETo from the HS equation were compared with CIMIS ETo at the same locations using available CIMIS data to determine correction factors to estimate CIMIS ETo from the HS ETo to account for spatial climate differences. CaI-SIMETAW also employs near real-time reference evapotranspiration （ETo） information from Spatial CIMIS, which is a model that combines weather station data and remote sensing to provide a grid of ETo information. A second database containing the available soil water

关键词： soil water balance crop water requirements weather generator water resource planning crop coefficient energy use

Positron Emission Projection Imaging:A technique for concentration field measurements in opaque industrial systems

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Particuology 2024年第11期94卷 1-15页

作者： Roberto hart-Villamil Jack Sykes Andy Ingram Christopher R.K.Windows-Yule Santosh Kumar Gupta School of Chemical Engineering University of BirminghamB152TTUK School of Physics and Astronomy University of BirminghamB152TTUK Hindustan Unilever R&D BengaluruKarnataka560066India

A novel Positron Emission Projection Imaging(PEPI)algorithm designed to compute the plane-projected spatial distribution of radiolabelled materials without the need for collimation is *** leveraging improved data efficiency,we have achieved a technique with enhanced spatial resolution and temporal resolution compared to previous PEPI *** of this algorithm was conducted using synthetic data generated from a digital twin of a PET scanner,demonstrating its accuracy for practical *** industrial advantage of this novel algorithm was applied in the imaging of laminar flow mixing within a ploughshare mixer,with the experimental results compared against those obtained from validated computational fluid dynamics(CFD)*** comparison highlights an important use case for PEPI as a robust validation tool for CFD simulations,crucial for enhancing industrial ***,which uses deeply penetrating gamma-photons,is now capable of imaging opaque fluids and solids in industrial *** directions for this work include further algorithmic refinements and expanding its application across various industrial systems,establishing PEPI as a robust tool for in-depth industrial process *** advancements presented here allow for optimized mixer design and enhanced process efficiency,extending the frontiers of tomographic imaging in industrial applications.

关键词： Positron emission projection imaging Positron emission particle tracking Computational fluid dynamics Mixing Ploughshare mixer

Analysis of expanded criteria to select candidates for active surveillance of low-risk prostate cancer

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Asian Journal of Andrology 2015年第2期17卷 248-252,I0008,I0009页

作者： Jung Ki Jo hart Sol Lee Young Ik Lee Sang Eun Lee Sung Kyu Hong Department of Urology Seoul National University Bundang Hospital Seongnam Korea.

We aimed to analyze the value of each criterion for clinically insignificant prostate cancer （PCa） in the selection of men for active surveillance （AS） of low-risk PCa. We identified 532 men who were treated with radical prostatectomy from 2006 to 2013 who met 4 or all 5 of the criteria for clinically insignificant PCa （clinical stage 〈 T1, prostate specific antigen [PSA] density 0.15, biopsy Gleason score 〈 6, number of positive biopsy cores 〈 2, and no core with 〉 50% involvement） and analyzed their pathologic and biochemical outcomes. Patients who met all 5 criteria for clinically insignificant PCa were designated as group A （n -- 172）, and those who met 4 of 5 criteria were designated as group B （n = 360）. The association of each criterion with adverse pathologic features was assessed via logistic regression analyses. Comparison of group A and B and also logistic regression analyses showed that PSA density 0.15 ng ml-1 and high （〉7） biopsy Gleason score were associated with adverse pathologic features. Higher （〉 Tlc） clinical stage was not associated with any adverse pathologic features. Although 〈 3 positive cores were not associated with any adverse pathology, 〉4 positive cores were associated with higher risk of extracapsular extension. Among potential candidates for AS, PSA density ~ 0.15 ng ml-~ and biopsy Gleason score ~ 6 pose significantly higher risks of harboring more aggressive disease. The eligibility criteria for AS may be expanded to include men with clinical stage T2 tumor and 3 positive cores.

关键词： prediction prostate prostatectomy prostatic neoplasms risk

Discovering the building blocks of atomic systems using machine learning:application to grain boundaries

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npj Computational Materials 2017年第1期3卷 212-218页

作者： Conrad W.Rosenbrock Eric R.Homer Gabor Csanyi Gus L.W.hart Department of Physics and Astronomy Brigham Young UniversityProvoUT 84602USA Department of Mechanical Engineering Brigham Young UniversityProvoUT 84602USA Engineering Laboratory University of CambridgeTrumpington StreetCambridge CB21PZUK

Machine learning has proven to be a valuable tool to approximate functions in high-dimensional ***,analysis of these models to extract the relevant physics is never as easy as applying machine learning to a large data set in the first *** we present a description of atomic systems that generates machine learning representations with a direct path to physical *** an example,we demonstrate its usefulness as a universal descriptor of grain boundary *** boundaries in crystalline materials are a quintessential example of a complex,high-dimensional system with broad impact on many physical properties including strength,ductility,corrosion resistance,crack resistance,and *** addition to modeling such properties,the method also provides insight into the physical“building blocks”that influence *** opens the way to discover the underlying physics behind behaviors by understanding which building blocks map to particular *** the structures are understood,they can then be optimized for desirable behaviors.

关键词： grain resistance corrosion

Are We Learning as Much as Possible from Spaceflight to Better Understand Health and Risks to Health on Earth, as Well as in Space?

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Journal of Biomedical Science and Engineering 2018年第6期11卷 109-118页

作者： David A. hart Human Performance Laboratory University of Calgary Calgary Canada Faculty of Kinesiology University of Calgary Calgary Canada Department of Surgery University of Calgary Calgary Canada McCaig Institute for Bone & Joint Health University of Calgary Calgary Canada Alberta Health Services Bone & Joint Health Strategic Clinical network Edmonton Canada

The objective of this review is to discuss the changes in human biology and physiology that occur when humans, who evolved on Earth for millions of years, now are subjected to space flight for extended periods of time, and how detailing such changes associated with space flight could help better understand risks for loss of health on Earth. Space programs invest heavily in the selection and training of astronauts. They also are investing in maintaining the health of astronauts, both for extensive stays in low earth orbit on ISS, and in preparation for deep space missions in the future. This effort is critical for the success of such missions as the n is small and the tasks needed to be performed in a hostile environment are complex and demanding. However, space is a unique environment, devoid of many of the “boundary conditions” that shaped human evolution (e.g. 1 g environment, magnetic fields, background radiation, oxygen, water, etc). Therefore, for humans to be successful in space, we need to learn to adapt and minimize the impact of an altered environment on human health. Conversely, we can also learn considerably from this altered environment for life on earth. The question is, are we getting the maximal information from life in space to learn about like on earth? The answer is likely no, and as such, our “Return on Investment” is not as great as it could be. Even though the number of astronauts is not large, what we can learn from them could help shape new questions for research focused on health for those on earth, as well is contribute to “precision health” from the study of astronaut diversity. This latter effort would contribute to both the health of astronauts identifying risks, as well as contribute to health on earth via better understanding of the human genome and epigenome, as well as factors contributing to risk for diseases on earth, particularly as individuals age and regulatory systems become altered. Better use of the International Space Station

关键词： Physiology Genome Epigenome Space Flight Precision Medicine Precision Health Silent Mutations Accelerated Aging