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Carbon dioxide enrichment affected flower numbers transiently and increased successful post-pollination development stably but without altering final acorn production in mature pedunculate oak (Quercus robur L.)

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Journal of Forestry Research 2024年第4期35卷 1-12页

作者： Ryan McClory richard h.ellis Martin Lukac Jo Clark Carolina Mayoral Kris M.hart Andrew R.G.Plackett A.Rob MacKenzie School of Agriculture Policy and DevelopmentUniversity of ReadingAgricultureEarley GateWhiteknights RoadPO Box 237Reading RG66EUUK Faculty of Forestry and Wood Sciences Czech University of Life Sciences PraguePrague 165000Czechia Future Trees Trust Harwell Innovation CentreBuilding 173Curie AvenueHarwellOxford OX110QGUK Birmingham Institute of Forest Research University of BirminghamEdgbastonBirmingham B152TTUK School of Biosciences University of BirminghamEdgbastonBirmingham B152TTUK School of Geography Earth and Environmental SciencesUniversity of BirminghamEdgbastonBirmingham B152TTUK

Acorn production in oak(Quercus spp.)shows considerable inter-annual variation,known as masting,which provides a natural defence against seed predators but a highly-variable supply of acorns for uses such as in commercial tree planting each *** emissions of greenhouse gases have been very widely reported to influence plant growth and seed or fruit size and quantity via the‘fertilisation effect’that leads to enhanced *** examine if acorn production in mature woodland communities will be affected by further increase in CO_(2),the contents of litter traps from a Free Air Carbon Enrichment(FACE)experiment in deciduous woodland in central England were analysed for numbers of flowers and acorns of pedunculate oak(Quercus robur L.)at different stages of development and their predation levels under ambient and elevated CO_(2) ***-annual variation in acorn numbers was considerable and cyclical between 2015 and 2021,with the greatest numbers of mature acorns in 2015,2017 and 2020 but almost none in *** numbers of flowers,enlarged cups,immature acorns,empty acorn cups,and galls in the litter traps also varied amongst years;comparatively high numbers of enlarged cups were recorded in 2018,suggesting *** at this site is a fruit maturation masting species(i.e.,the extent of abortion of pollinated flowers during acorn development affects mature acorn numbers greatly).Raising the atmospheric CO_(2) concentration by 150μL L^(−1),from early 2017,increased the numbers of immature acorns,and all acorn evidence(empty cups+immature acorns+mature acorns)detected in the litter traps compared to ambient controls by 2021,but did not consistently affect the numbers of flowers,enlarged cups,empty cups,or mature *** number of flowers in the elevated CO_(2) plots’litter traps was greater in 2018 than 2017,one year after CO_(2) enrichment began,whereas numbers declined in ambient *** with CO_(2) also increased the number o

关键词： Quercus robur L. Acorns Masting Pedunculate oak Carbon dioxide

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DNA barcoding of Pedicularis L.(Orobanchaceae):Evaluating four universal barcode loci in a large and hemiparasitic genus

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Journal of Systematics and Evolution 2011年第5期49卷 425-437页

作者： richard h.REE Department of Botany Field Museum of Natural History

One application of DNA barcoding is species identification based on sequences of a short and standardized DNA *** plants,various DNA regions,alone or in combination,have been proposed and investigated,but consensus on a universal plant barcode remains *** this study,we tested the utility of four candidate barcoding regions(rbcL,matK,trnh-psbA,and internal transcribed spacer(ITS)) as DNA barcodes for discriminating species in a large and hemiparasitic genus Pedicularis(Orobanchaceae).Amplification and sequencing was successful using single primer pairs for rbcL,trnh-psbA,and ITS,whereas two primer pairs were required for *** of sequence divergence commonly showed a "barcoding gap",that is,a bimodal frequency distribution of pairwise distances representing genetic diversity within and between species,*** primer universality,ease of amplification and sequencing,and performance in discriminating species,we found the most effective single-region barcode for Pedicularis to be ITS,and the most effective two-region barcode to be rbcL + *** discriminated at least 78% of the 88 species and correctly identified at least 89% of the sequences in our sample,and were effective in placing unidentified samples in known species *** results suggest that DNA barcoding has the potential to aid taxonomic research in Pedicularis,a species-rich cosmopolitan clade much in need of revision,as well as ecological studies in its center of diversity,the hengduan Mountains region of China.

关键词： DNA barcode hengduan Mountains region ITS Pedicularis rbcL species identification.

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Arterial faults and their role in mineralizing systems

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Geoscience Frontiers 2019年第6期10卷 2093-2100页

作者： richard h.Sibson Department of Geology University of Otago

In quartzo-feldspathic continental crust with moderate-to-high heat flow,seismic activity extends to depths of 10-20 km,bounded by isotherms in the 350-450 C *** overpressuring above hydrostatic in seismogenic crust,is heterogeneous but tends to develop in the lower seismogenic zone(basal seismogenic zone reservoir=***) where the transition between hydrostatically pressured and overpressured crust is likely an irregular,time-dependent.3-D interface with overpressuring concentrated around active faults and their ductile shear zone *** term Arterial Fault is applied to fault structures that root in portions of the crust where pore fluids are overpressured(***> hydrostatic pressure) and serve as feeders for such fluids and their contained solutes into overlying parts of the *** arterial flow may occur on any type of fault,it is most likely to be associated with reverse faults in areas of horizontal compression where fluid overpressuring is most easily *** stability and flow permeability of faults are both affected by the state of stress on the fault(shear stress,τ;normal stress,σn),the level of pore-fluid pressure,Pf,and episodes of fault slip,allowing for a complex interplay between fault movement and fluid *** seismically active faults the time dependence of permeability is critical,leading to fault-valve behaviour whereby overpressures accumulate at depth during interseismic intervals with fluid discharged along enhanced fault-fracture permeability following each rupture *** of mineralization also suggest that flow along faults is non-uniform,concentrating along tortuous pathways within the fault *** hydrostatic head above ground level for near-lithostatic overpressures at depth(h of zone) provides a measure of arterial *** for arterial faults include fault systems developed in compacting sedimentary basins,faults penetrating zones of active plutonic intrusi

关键词： Fault conduits Fluid overpressures Arterial potential Valve action Mineralization

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Luminescence of Er^(3+) in Oxyfluoride Transparent Glass-Ceramics

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Journal of Rare Earths 2006年第6期24卷 699-705页

作者： Akira Ueda Steven h Morgan richard Mu Department of Physics Fisk University NashvilleTN 37208 USA

Erbium doped silicate, germanate, and tellurium-germanate oxyfluoride glasses were prepared in a bulk form. Through appropriate heat treatment of the as-prepared glasses, transparent glass-ceramics （TGCs） were obtained with the formation of β-PbF2：Er^3＋ nanocrystals in the glass matrix were confirmed by X-ray ***-defined diffraction peaks were observed in the samples after heat-treatment. The average crystal diameter of these precipitated crystals from full-width at half-maximum （FWhM） of the diffraction peak was estimated to be between 8 and 13 nm. Optical absorption, photoluminescence, and upconversion luminescence were measured on as-prepared glass and glass-ceramics. Luminescence spectra in the TGC samples revealed well-resolved, sharp stark-splitting peaks, which indicates that a majority of Er^3＋ ions has been incorporated into the crystalline phase of the nanocrystals. The intensity of the visible and near infrared luminescence mostly increases in TSG compared to that in the as-prepared glass. In 1.53 μm absorption and emission bands, the maximum absorption peak is blue-shifted from 1531 to 1507 nm, whereas the maximum emission peak is redshifted from 1535 to 1543 nm in TGC, as compared with that in glass. The bandwidth at half-maximum （BWhM） of the emission band is significantly broader in TGC than in glass, which is beneficial to the erbium-doped fiber amplifier （EDFA）. Upconversion luminescence was measured using 800 nm near-infrared light excitation. Drastically increased upconversion 1 was observed from the TGC as compared to that from their corresponding as-prepared glasses. In addition to a strong green emission centered at 545 nm because of ^4S3/2→^4I15/2 transition and a weaker red emission centered at 662 nm because of ^4F9/2→^4I15/2 transition, generally seen from the Er^3＋ doped glasses, two violet emissions centered at 410 nm because of ^2h9/2→^4I15/2 transition and centered at 379 nm because of ^4G11/2→^4I15/2 transition were also o

关键词： luminescence transparent glass-ceramics rare earths

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Porphyria cutanea tarda as a complication of therapy for chronic hepatitis C

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World Journal of Gastroenterology 2008年第38期14卷 5913-5915页

作者： James Azim heather McCurdy richard h Moseley Division of Gastroenterology Department of Internal Medicine Department of Veterans Affairs Medical Center and University of Michigan School of Medicine Ann ArborMichigan United States

There is a strong association between porphyria cutanea tarda (PCT) and chronic viral hepatitis C. Therapy for chronic viral hepatitis C may improve PCT. however, there are only a few reports of the de novo development of PCT during therapy for chronic viral hepatitis C. We describe the development of PCT in a 56-year-old patient with chronic viral hepatitis C after 12 wk of peginterferon/ribavirin therapy. In addition, the patient was homozygous for the h63D hereditary hemochromatosis gene (hFE ) mutation. The association of PCT with chronic viral hepatitis C and the possible role of hepatic iron overload and ribavirin-induced hemolytic anemia in the development of PCT during therapy for chronic viral hepatitis C are discussed.

关键词： Porphyria hepatitis C virus Ribavirin Pegylated interferon hemochromatosis

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Identification of specific genes and pathways involved in NSAIDs-induced apoptosis of human colon cancer cells

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World Journal of Gastroenterology 2006年第40期12卷 6446-6452页

作者： richard h huang Jianyuan Chai Andrzej S Tarnawski Department of Medicine Division of Gastroenterology University of California Irvine and VA Long Beach Healthcare System California United States Department of Medicine University of California Irvine and VA Long Beach Healthcare System California United States

AIM: To study whether indomethacin (IND), a nonselective cyclooxygenase (COX) inhibitor or NS-398 (NS), a COX-2-selective inhibitor, induces apoptosis in human colon cancer cells and which apoptosis-related genes and pathways are involved. METhODS: human colon cancer Caco-2 cells were treated with either: placebo, IND (0.05-0.5 mmol/L) or NS (0.01-0.2 mmol/L) for 1, 5 and 18 h. We then studied: (1) Cell death by the TUNEL method, (2) mRNA expression of 96 apoptosis-related genes using DNA microarray, (3) expression of selected apoptosis related proteins by Western blotting. RESULTS: Both IND and NS induced apoptosis in 30%-50% of Caco-2 cells in a dose dependent manner. IND (0.1 mmol/L for 1 h) significantly up-regulated pro-apoptotic genes in four families: (1) TNF receptor and ligand, (2) Caspase, (3) Bcl-2 and (4) Caspase recruiting domain. NS treatment up-regulated similar pro-apoptotic genes as IND. In addition, IND also down-regulated anti-apoptotic genes of the IAP family. CONCLUSION: (1) Both non-selective and COX-2-selective NSAIDs induce apoptosis in colon cancer cells in a dose dependent manner. (2) Both NSAIDs induce apoptosis by activating two main apoptotic pathways: the death receptor pathway (involving TNF-R) and the mitochondrial pathway. (3) IND induces apoptosis by up-regulating pro-apoptotic genes and down-regulating anti-apoptotic genes, while NS only up-regulates pro-apoptotic genes. (4) Induction of apoptosis in coloncancer cells by NSAIDs may explain in part, their inhibitory action on colon cancer growth.

关键词： Nonsteroidal anti-inflammatory drugs Colon cancer Apoptosis Cyclooxygenase cDNA microarray

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Assets and tactics in a mating market： Economic models of negotiation offer insights into animal courtship dynamics on the lek

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Current Zoology 2011年第2期57卷 225-236页

作者： Gail L. PATRICELLI Alan h. KRAKAUER richard MCELREATh Department of Evolution and Ecology University of California Davis CA 95616 USA Department of Anthropology University of California Davis CA 95616 USA

Economists study negotiation as a series of events--partner choice, information gathering, bargaining, etc.--with each step of the process affecting the outcome of the next, and the optimal decision at each stage depending on the player＇s bargaining power. The context in which these negotiations occur--the market--is critical, since players can adjust their behaviors in response to outside offers. Animals similarly are faced with sequential decisions regarding courtship： who to court, how to approach a potential mate, at what level to display, when to give up, etc. Thus economic models of negotiation in a market provide a framework in which we can view not just the outcome of courtship （assortative mating）, but also the process, where each sex can use tactics to improve their negotiating outcome, using the assets that they have available. here we propose to use negotiation as a conceptual framework to explore the factors promoting tactical adjustments during sequential stages of courtship in lekking species. Our goal is to discuss the utility of negotiation as a heuristic tool, as well as the promise and peril of co-opting game theoretic models from economics to understand animal interactions. We will provide a brief overview of a few areas where we see promise for using negotiation as a framework to understand animal courtship dynamics： choice of a display territory, tactical partner choice for negotiation, approaching a potential partner and courtship haggling .

关键词： Bargaining Game theory Lek Sexual selection Signaling Negotiation

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Developing Skin Analogues for a Robotic Octopus

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Journal of Bionic Engineering 2012年第3期9卷 385-390页

作者： Jinping hou richard h. C. Bonser George Jeronimidis Centre for Biomimetics School of Construction Management and Engineering University of Reading Reading RG6 6AY UK School of Engineering and Design Brunel University Uxbridge Middlesex UB8 3PH UK

In order to fabricate a biomimetic skin for an octopus inspired robot, a new process was developed based on mechanical properties measured from real octopus skin. Various knitted nylon textiles were tested and the one of 10-denier nylon was chosen as reinforcement. A combination of Ecoflex 0030 and 0010 silicone rubbers was used as matrix of the composite to obtain the right stiffness for the skin-analogue system. The open mould fabrication process developed allows air bubble to escape easily and the artificial skin produced was thin and waterproof. Material properties of the biomimetic skin were char- acterised using static tensile and instrumented scissors cutting tests. The Young＇s moduli of the artificial skin are 0.08 MPa and 0.13 MPa in the longitudinal and transverse directions, which are much lower than those of the octopus skin. The strength and fracture toughness of the artificial skin, on the other hand are higher than those of real octopus skins. Conically-shaped skin prototypes to be used to cover the robotic arm unit were manufactured and tested. The biomimetic skin prototype was stiff enough to maintain it conical shape when filled with water. The driving force for elongation was reduced significantly compared with previous prototypes.

关键词： biomimetic skin artefact octopus robot textile composite

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Design of a Biomimetic Skin for an Octopus-Inspired Robot - Part I： Characterising Octopus Skin

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Journal of Bionic Engineering 2011年第3期8卷 288-296页

作者： Jinping hou richard h. C. Bonser George Jeronimidis Centre for Biomimetics School of Construction Management and Engineering University of Reading Reading RG6 6AY UK

Octopus skin samples were tested under quasi-static and scissor cutting conditions to measure the in-plane material prop- erties and fracture toughness. Samples from all eight arms of one octopus were tested statically to investigate how properties vary from arm to arm. Another nine octopus skins were measured to study the influence of body mass on skin properties. In- fluence of specimen location on skin mechanical properties was also studied. Material properties of skin, i.e. the Young＇s modulus, ultimate stress, failure strain and fracture toughness have been plotted against the position of skin along the length of arm or body. Statistical studies were carried out to help analyzing experimental data obtained. Results of this work will be used as guidelines for the design and development of artificial skins for an octopus-inspired robot.

关键词： octopus skin uniaxial tension scissor cutting Young's modulus failure strain fracture toughness

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Design of a Biomimetic Skin for an Octopus-Inspired Robot - Part Ⅱ： Development of the Skin Artefact

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Journal of Bionic Engineering 2011年第3期8卷 297-304页

作者： Jinping hou richard h. C. Bonser George Jeronimidis Centre for Biomimetics School of Construction Management and Engineering UniversiO~ of Reading Reading RG6 6A Y UK

In order to develop skin artefact for an octopus-inspired robot arm, which is designed to be able to elongate 60% of its original length, silicone nlbber and knitted nylon sheet were selected to manufacture an artificial skin, due to their higher elastic strain and high flexibility. Tensile and scissors cutting tests were conducted to characterise the matrix and reinforcing materials and the skin artefact. Material properties of the individual and the composite materials were compared with the measured properties of real octopus skin presented ill Part I. The Young＇s modulus of the skin should be below 20 MPa and the elastic strain range should be over 60%. The fracture toughness should be at least 0.9 kJ.m 2. Tubes made of the skin artefact filled with liquid were tested to study volume change under deformation. Finite element analysis model was developed to simulate the material and arm structure under tensile loading. Results show that the skin artefact developed has similar mechanical properties as the real octopus skin and satisfies all the design specifications of the OCTOPUS robot.

关键词： octopus skin static tensile test toughness skin artefact nylon/silicone composite

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