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Maintenance of Species Differences in Closely Related Tetraploid Parasitic Euphrasia (Orobanchaceae) on an Isolated Island

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Plant Communications 2020年第6期1卷 85-99页

作者： Hannes Becher Max R.Brown Gavin Powell Chris Metherell nick j.riddifordand Alex D.Twyford University of Edinburgh School of Biological SciencesInstitute of Evolutionary BiologyCharlotte Auerbach RoadEdinburgh EH93FLUK Royal Botanic Garden Edinburgh 20A Inverleith RowEdinburgh EH35LRUK Botanical Society of Britain and Ireland 4 High Firs CrescentHarpendenHertfordshire AL51NAUK Schoolton Fair IsleShetland ZE29JUUK

Polyploidy is pervasive in angiosperm evolution and plays important roles in adaptation and ***,polyploid groups are understudied due to complex sequence homology,challenging genome assembly,and taxonomic ***,we study adaptive divergence in taxonomically complex eyebrights(Euphrasia),where recent divergence,phenotypic plasticity,and hybridization blur species *** focus on three closely related tetraploid species with contrasting ecological preferences that are sympatric on Fair Isle,a small isolated island in the British *** a common garden experiment,we show a genetic component to the morphological differences present between these *** wholegenome sequencing and a novel k-mer approach we call“Tetmer”,we demonstrate that the species are of allopolyploid origin,with a sub-genome divergence of approximately 5%.Using2 million SNPs,we show sub-genome homology across species,with a very low sequence divergence characteristic of recent *** genetic variation is broadly structured by species,with clear divergence of Fair Isle heathland Euphrasia micrantha,while grassland Euphrasia arctica and coastal Euphrasia foulaensis are more closely ***,we show that tetraploid Euphrasia is a system of allopolyploids of postglacial species divergence,where adaptation to novel environments may be conferred by old variants rearranged into new genetic lineages.

关键词： incipient speciation k-mer spectrum allopolyploidy tetraploid divergence with gene flow taxonomic complexity

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A photogrammetric approach for quantifying the evolution of rock joint void geometry under varying contact states

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International journal of Mining Science and Technology 2024年第4期34卷 461-477页

作者： Rui Yong Changshuo Wang nick Barton Shigui Du Institute of Rock Mechanics Ningbo UniversityNingbo 315211China nick Barton&Associates Fjordveien 65cHøvik 1363Norway

Accurate measurement of the evolution of rock joint void geometry is essential for comprehending the distribution characteristics of asperities responsible for shear and seepage ***,existing techniques often require specialized equipment and skilled operators,posing practical *** this study,a cost-effective photogrammetric approach is ***,local coordinate systems are established to facilitate the alignment and precise quantification of the relative position between two halves of a rock ***/pull tests are conducted on rock joints with varying roughness levels to induce different contact states.A high-precision laser scanner serves as a benchmark for evaluating the photogrammetry *** certain deviations exist,the measured evolution of void geometry is generally consistent with the qualitative findings of previous *** photogrammetric measurements yield comparable accuracy to laser scanning,with maximum errors of 13.2%for aperture and 14.4%for void *** joint matching coefficient(jMC)measurement errors are below 20%.Larger measurement errors occur primarily in highly mismatched rock joints with jMC values below 0.2,but even in cases where measurement errors exceed 80%,the maximum jMC error is only ***,the proposed photogrammetric approach holds promise for widespread application in void geometry measurements in rock joints.

关键词： Rock joint Void geometry evolution Photogrammetry Aperture Void volume joint matching coefficient

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The effect of temperature on ionic liquid modified Fe-N-C catalysts for alkaline oxygen reduction reaction

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journal of Energy Chemistry 2022年第5期31卷 324-329页

作者： Thomas Wolker Kai Brunnengräber Ioanna Martinaiou nick Lorenz Gui-Rong Zhang Ulrike I.Kramm Bastian j.M.Etzold Department of Chemistry Ernst-Berl-Institut für Technische und Makromolekulare ChemieTechnical University of Darmstadt64287 DarmstadtGermany Department of Chemistry Catalysts and Electrocatalysts GroupTechnical University of Darmstadt64287 DarmstadtGermany Graduate School of Excellence Energy Science and Engineering Technical University of Darmstadt64287 DarmstadtGermany Department of Materials and Earth Sciences Technical University of Darmstadt64287 DarmstadtGermany School of Chemical Engineering and Technology Tiangong UniversityTianjin 300387China

Modifying solid catalysts with an ionic liquid layer is an effective approach for boosting the performance of both Pt-based and non-precious metal catalysts toward the oxygen reduction reaction. While most studies operated at room temperature it remains unclear whether the IL-associated boosting effect can be maintained at elevated temperature, which is of high relevance for practical applications in low temperature fuel cells. Herein, Fe-N-C catalysts were modified by introducing small amounts of hydrophobic ionic liquid, resulting in boosted electrocatalytic activity towards the alkaline oxygen reduction reaction at room temperature. It is demonstrated that the boosting effect can be maintained and even strengthened when increasing the electrolyte temperature up to 70℃. These findings show for the first time that the incorporation of ionic liquid is a suited method to obtain advanced noble metal-free electrocatalysts that can be applied at operating temperature condition.

关键词： Oxygen reduction reaction Non-precious metal catalyst Ionic liquid Fe-N-C catalyst Temperature effect

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Using Twitter Bios to Measure Changes in Self-Identity:Are Americans Defining Themselves More Politically Over Time?

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journal of Social Computing 2021年第1期2卷 1-13页

作者： nick Rogers jason j.jones Department of Sociology Stony Brook UniversityStony BrookNY 11794USA

Are Americans weaving their political views more tightly into the fabric of their self-identity over time?If so,then we might expect partisan disagreements to continue becoming more emotional,tribal,and *** recent scholarship has speculated that this politicization of Americans’identity is occurring,but there has been little compelling attempt to quantify the phenomenon,largely because the concept of identity is notoriously difficult to *** introduce here a methodology,Longitudinal Online Profile Sampling(LOPS),which affords quantifiable insights into the way individuals amend their identity over *** this method,we analyze millions of“bios”on the microblogging site Twitter over a 4-year span,and conclude that the average American user is increasingly integrating politics into their social *** on the site are adding political words to their bios at a higher rate than any other category of words we measured,and are now more likely to describe themselves by their political affiliation than their religious *** data suggest that this is due to both cohort and individual-level effects.

关键词： identity social identity theory social media ideology political polarization Twitter

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A spectral response approach for detecting dominant phytoplankton size class from satellite remote sensing

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Acta Oceanologica Sinica 2010年第2期29卷 14-32页

作者： Robert j W Brewin Samantha j Lavender nick j Hardman-Mountford Takafumi Hirata School of Marine Science and Engineering University of Plymouth UK ARGANS Ltd Plymouth UK Plymouth Marine Laboratory (PML) Plymouth UK National Centre for Earth Observation PMLPlymouthUK Graduate School of Environmental Earth Science Hokkaido University NIOVV5kita-kuSapporo 060-0810 Japan National Centre for Earth Observation PMLPlymouthUK Graduate School of Environmental Earth ScienceHokkaido University NIOVV5kita-kuSapporo 060-0810Japan Graduate School of Environmental Earth Science Hokkaido University NIOVV5kita-kuSapporo 060-0810Japan

An important goal in ocean colour remote sensing is to accurately detect different phytoplankton groups with the potential uses including the validation of multi-phytoplankton carbon cycle models; synoptically monitoring the health of our oceans, and improving our understanding of the bio-geochemical interactions between phytoplankton and their environment. In this paper a new algorithm is developed for detecting three dominant phytoplankton size classes based on distinct differences in their optical signatures. The technique is validated against an independent coupled satellite reflectance and in situ pigment dataset and run on the 10-year NASA Sea viewing Wide Field of view Sensor （SeaWiFS） data series. Results indicate that on average 3.6% of the global oceanic surface layer is dominated by microplankton, 18.0% by nanoplankton and 78.4% by pieoplankton. Results, however, are seen to vary depending on season and ocean basin.

关键词： phytoplankton size remote sensing absorption ocean colour SeaWiFS

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Geochronological constraints on the metamorphic sole of the Semail ophiolite in the United Arab Emirates

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Geoscience Frontiers 2016年第4期7卷 609-619页

作者： nick M.W.Roberts Robert j.Thomas joachim jacobs NERC Isotope Geosciences Laboratory British Geological SurveyKeyworthNG12 5GGUK Council for Geoscience P.O.Box 572Bellville 7535South Africa University of Bergen.Department of Earth Science PB 78035020 BergenNorway Norwegian Polar Institute Fram Centre9296 TromsoNorway

The Semail ophiolite of Oman and the United Arab Emirates （UAE） provides the best preserved large slice of oceanic lithosphere exposed on the continental crust, and offers unique opportunities to study processes of ocean crust formation, subduction initiation and obduction. Metamorphic rocks exposed in the eastern UAE have traditionally been interpreted as a metamorphic sole to the Semail ophiolite. However, there has been some debate over the possibility that the exposures contain components of older Arabian continental crust. To help answer this question, presented here are new zircon and futile U-Pb geochronological data from various units of the metamorphic rocks. Zircon was absent in most samples. Those that yielded zircon and futile provide dominant single age populations that are 95-93 Ma, partially overlapping with the known age of oceanic crust formation （96.5-94.5 Ma）, and partially overlapping with cooling ages of the metamorphic rocks （95 90 Ma）. The data are interpreted as dating high-grade metamorphism during subduction burial of the sediments into hot mantle lithosphere, and rapid cooling during their subsequent exhumation. A few discordant zircon ages, interpreted as late Neoproterozoic and younger, represent minor detrital input from the continent. No evidence is found in favour of the existence of older Arabian continental crust within the metamorphic rocks of the UAE.

关键词： Semail ophiolite United Arab Emirates Metamorphic sole U-Pb geochronology Zircon Rutile

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Interference from HONO in the measurement of ambient air NO2 via photolytic conversion and quantification of NO

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journal of Environmental Sciences 2021年第9期33卷 184-193页

作者： Nicholas j.Gingerysty Charles A.Odame-Ankrah nick jordan Hans D.Osthoff Department of Chemistry University of CalgaryCalgary AB T2N 1N4Canada Global Analyzer Systems Ltd. Calgary AB T2E 7L6Canada

The reference method to quantify mixing ratios of the criteria air pollutant nitrogen dioxide(NO_(2)) is NO-O_(3) chemiluminescence(CL), in which mixing ratios of nitric oxide(NO) are measured by sampling ambient air directly, and mixing ratios of NO_(x)(= sum of NO and NO_(2))are measured by converting NO_(2) to NO using, for example, heated molybdenum catalyst or,more selectively, photolytic conversion(P-CL).In this work, the nitrous acid(HONO) interference in the measurement of NO_(2) by P-CL was *** with two photolytic NO2 converters are *** first used radiation centered at 395 nm, a wavelength region commonly utilized in *** second used light at 415 nm, where the overlap with the HONO absorption spectrum and hence its photolysis rate are *** ratios of NO_(2),NO_(x) and HONO entering and exiting the converters were quantified by Thermal Dissociation Cavity Ring-down Spectroscopy(TD-CRDS).Both converters exhibited high NO_(2) conversion efficiency(CF_(NO2);> 90%) and partial conversion of *** of CF against flow rate were consistent with photolysis frequencies of 4.2 s^(-1) and 2.9 s^(-1) for NO_(2) and 0.25 s^(-1) and 0.10 s^(-1) for HONO at 395 nm and 415 nm, *** larger than predicted from the overlap of the emission and HONO absorption *** results imply that measurements of NO2 by P-CL marginally but systematically overestimate true NO_(2) concentrations,and that this interference should be considered in environments with high HONO:NO_(2) ratios such as the marine boundary layer or in biomass burning plumes.

关键词： Photolytic conversion of NO_(2) HONO interference

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Predicting june Mean Rainfall in the Middle/Lower Yangtze River Basin

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Advances in Atmospheric Sciences 2020年第1期37卷 29-41页

作者： Gill M.MARTIN nick j.DUNSTONE Adam A.SCAIFE Philip E.BETT Met Office Exeter

We demonstrate that there is significant skill in the GloSea5 operational seasonal forecasting system for predicting june mean rainfall in the middle/lower Yangtze River basin up to four months in *** of the rainfall in this region during june is contributed by the mei-yu rain *** find that similar skill exists for predicting the East Asian summer monsoon index(EASMI)on monthly time scales,and that the latter could be used as a proxy to predict the regional ***,there appears to be little to be gained from using the predicted EASMI as a proxy for regional rainfall on monthly time scales compared with predicting the rainfall *** interannual variability of the june mean rainfall is affected by synoptic and intraseasonal variations,which may be inherently unpredictable on the seasonal forecasting time scale,the major influence of equatorial Pacific sea surface temperatures from the preceding winter on the june mean rainfall is captured by the model through their influence on the western North Pacific subtropical *** ability to predict the june mean rainfall in the middle and lower Yangtze River basin at a lead time of up to 4 months suggests the potential for providing early information to contingency planners on the availability of water during the summer season.

关键词： forecast skill EASMI monthly mean rainfall East Asian summer monsoon Yangtze River basin

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Pien Tze Huang Inhibits Proliferation of Colorectal Cancer Cells through Suppressing PNO1 Expression and Activating p53/p21 Signaling Pathway

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Chinese journal of Integrative Medicine 2024年第6期30卷 515-524页

作者： CAO Liu-jing LIU Li-ya CHEN You-qin HAN Yu-ying WEI Li-hui YAO Meng-ying FANG Yi WU Mei-zhu CHENG Ying Thomas j.Sferra LIU Hui-xin LI Li PENG jun SHEN A-ling Clinical Research Institute the Second Affiliated Hospital&Academy of Integrative MedicineFujian University of Traditional Chinese MedicineFuzhou350122China Fujian Key Laboratory of Integrative Medicine in Geriatrics Fujian University of Traditional Chinese MedicineFuzhou350122China Department of Pediatrics Case Western Reserve University School of MedicineUH Rainbow Babies and Children’s HospitalClevelandOH44106USA Innovation and Transformation Center Fujian University of Traditional Chinese MedicineFuzhou350122China Department of Health Management Fujian Provincial HospitalShengli Clinical College of Fujian Medical UniversityFuzhou000000China

ObjectiveTo explore the regulatory effect of Pien Tze Huang (PZH) on targeting partner of NOB1 (PNO1) and it’s down-stream mediators in colorectal cancer (CRC) *** polymerase chain reaction was performed to determine mRNA levels of PNO1, TP53, and CDKN1A. Western blotting was performed to determine protein levels of PNO1, p53, and p21. HCT-8 cells were transduced with a lentivirus over-expressing PNO1. Colony formation assay was used to detect cell survival in PNO1 overexpression of HCT-8 cells after PZH treatment. Cell-cycle distribution, cell viability and cell apoptosis were performed to identify the effect of PNO1 overexpression on cell proliferation and apoptosis of HCT-8 cells after PZH treatment. Xenograft BALB/c nude mice bearing HCT116 cells transduced with sh-PNO1 or sh-Ctrl lentivirus were evaluated. Western blot assay was performed to detect PNO1, p53, p21 and PCNA expression in tumor sections. Terminal deoxynucleotidyl transferase dUTP nick end labling (TUNEL) assay was used to determine the apoptotic cells in *** treatment decreased cell viability, down-regulated PNO1 expression, and up-regulated p53 and p21 expressions in HCT-8 cells (P<0.05). PNO1 overexpression attenuated the effects of PZH treatment, including the expression of p53 and p21, cell growth, cell viability, cell cycle arrest and cell apoptosis in vitro (P<0.05). PNO1 knockdown eliminated the effects of PZH treatment on tumor growth, inhibiting cell proliferation inhibition and apoptosis induction in vivo (P<0.05). Similarly, PNO1 knockdown attenuated the effects of PZH treatment on the down-regulation of PNO1 and up-regulation of p53 and p21 in vivo (P<0.05).ConclusionThe mechanism by which PZH induces its CRC anti-proliferative effect is at least in part by regulating the expression of PNO1 and its downstream targets p53 and p21.

关键词： colorectal cancer Pien Tze Huang Chinese medicine partner of NOB1 proliferation p53/p21 pathway

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"Miles wide and miles deep"-Exploring the depth and breadth of geoscience during the first ten years of Geoscience Frontiers

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Geoscience Frontiers 2019年第3期10卷 1219-1221页

作者： Christopher j. Spencer nick M.W.Roberts Damian Nance The Institute of Geoscience Research (TIGeR) School of Earth and Planetary Sciences Curtin University NERC Isotope Geosciences Laboratory British Geological Survey Department of Geological Sciences Ohio University Department of Geology and Geophysics Yale University

When early explorers first crossed the Platte River in what is now Nebraska (USA), it was said the river was “a mile wide and an inch deep”(Mokler, 1923;Smith, 1971). This phrase was used to describe not only the difficulty in crossing the river but also in navigating its length. The trouble with a river being too wide is the risk that it won’t provide the depth necessary to be useful. The same thing can be said of multidisciplinary scientific journals. While a journal can claim to be multidisciplinary, there is a risk of it being so broad that its articles can only engage the reader at a superficial level. Nothing could be further from the truth with Geoscience Frontiers. Over the past ten years, this journal has successfully navigated the wide breadth of geoscience while providing a level of depth and detail that rivals discipline-specific journals.

关键词： engage its was can past be is now

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