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Journal of Integrative Plant Biology 2014年第5期56卷 505-515页

作者： Miguel Garriga Jorge B. Retamales sebastián Romero-Bravo peter d.s. caligari Gustavo A. Lobos Faculty of Agricultural sciences Plant Breeding and Phenomic Center Universidad de Talca Instituto de Biología Vegetaly Biotecnología Universidad de Talca

Chlorophyll and anthocyanin contents provide a valuable indicator of the status of a plant’s physiology, but to be more widely utilized it needs to be assessed easily and non‐d.s.ructively. This is particularly evident in terms of assessing and exploiting germplasm for plant‐breeding programs. We report, for the first time, experiments with Fragaria chiloensis（L.）duch. and the estimation of the effects of response to salinity stress（0, 30, and 60 mmol NaCl/L） in terms of these pigments content and gas exchange. It is shown that both pigments（which interestingly, themselves show a high correlation） give a good indication of stress response. Both pigments can be accurately predicted using spectral reflectance indices（sRI）;however, the accuracy of the predictions was slightly improved using multilinear regression analysis models and genetic algorithm analysis. specifically for chlorophyll content, unlike other species, the use of published.s.I gave better indications ofstress response than Normalized difference Vegetation *** effect of salt on gas exchange is only evident at the highest concentration and.s.me sRI gave better prediction performance than the known Photochemical Reflectance Index. This information will therefore be useful for identifying tolerant genotypes to salt stress for incorporation in breeding programs.

关键词： Gas exchange high‐throughput phenotyping pigment phenomic photosynthesis reflectance spectral reflectance indices

shot-noise limited, supercontinuum-based optical coherence tomography

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Light(science & Applications) 2021年第7期10卷 1372-1384页

作者： shreesha Rao d.s. Mikkel Jensen Lars Grüner-Nielsen Jesper Toft Olsen peter Heid.s.hka Björn Kemper Jürgen schnekenburger Martin Glud Mette Mogensen Niels Møller Israelsen Ole Bang dTU Fotonik Dept.of Photonics EngineeringTechnical University of DenmarkØrsteds Plads2800 Kongens LyngbyDenmark NKT Photonics A/s Blokken 843460 BirkerødDenmark department of Ophthalmology University of Münster Medical CentreDomagkstr.15D-48149 MünsterGermany Biomedical Technology Center of the Medical Faculty University of MünsterMendelstr.17D-48149 MünsterGermany department of dermatology Bisbebjerg HospitalUniversity of CopenhagenBispebjerg Bakke 232400 Copenhagen NVDenmark

We present the first demonstration of shot-noise limited.s.percontinuum-based.s.ectral domain optical coherence tomography(sd-OCT)with an axial resolution of 5.9μm at a center wavelength of 1370 *** supercontinuumbased.s.-OCT systems cannot be operated in the shot-noise limited detection regime because of severe pulse-topulse relative intensity noise of the supercontinuum *** overcome this d.s.dvantage,we have developed a low-noise supercontinuum source based on an all-normal d.s.ersion(ANdi)fiber,pumped by a femtosecond *** noise performance of our 90 MHz ANdi fiber-based.s.percontinuum source is compared to that of two commercial sources operating at 80 and 320 MHz repetition *** show that the low-noise of the ANdi fiber-based.s.percontinuum source improves the OCT images significantly in terms of both higher contrast,better sensitivity,and improved *** sd-OCT imaging of skin,retina,and multilayer stacks we conclude that supercontinuumbased.s.-OCT can enter the domain of shot-noise limited detection.

关键词： fiber optical pumped

Biomimetic flexible plate actuators are faster and more efficient with a passive attachment

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Acta Mechanica sinica 2016年第6期32卷 1001-1011页

作者： peter d.Yeh Alexander Alexeev George W.Woodruff school of Mechanical Engineering Georgia Institute of Technology

Using three-dimensional computer simulations, we probe biomimetic free swimming of an internally actuated flexible plate in the regime near the first natural frequency. The plate is driven by an oscillating internal moment approximating the actuation mechanism of a piezoelectric macro fiber composite (MFC) bimorph. We show in our simulations that the addition of a passive attachment increases both swimming velocity and efficiency. specifically, if the active and passive sections are of similar size, the overall performance is the best. We determine that this optimum is a result of two competing factors. If the passive section is too large, then the actuated portion is unable to generate substantial deflection to create sufficient thrust. On the other hand, a large actuated.s.ction leads to a bending pattern that is inefficient at generating thrust especially at higher frequencies.

关键词： Flexible plate Biomimetic Lattice Boltzmann Fluid.s.ructure interaction Robotic fish Piezoelectric actuator

Pitfalls and promises of bile duct alternatives:There is plenty of room in the regenerative surgery

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World Journal of Gastroenterology 2023年第30期29卷 4701-4705页

作者： Ilya d Klabukov denis s Baranovskii peter V shegay Andrey d Kaprin department of Regenerative Medicine National Medical Research Radiological Center of the Ministry of Health of the Russian FederationObninsk 249036Russia Center for Innovative Radiological and Regenerative Technologies National Medical Research Radiological Center of the Ministry of Health of the Russian FederationObninsk 249036Russia

Current abdominal surgery has several approaches for biliary ***,the creation of functional and clinically applicable bile duct substitutes still represents an unmet *** the paper by Miyazawa and colleagues,approaches to the creation of bile duct alternatives were summarized,and the reasons for the lack of development in this area were *** history of bile duct surgery since the nineteenth century was also traced,leading to the conclusion that the use of bioabsorbable materials holds promise for the creation of bile duct substitutes in the *** suggest three ideas that may stimulate progress in the field of bile duct substitute ***,a systematic analysis of the causative factors leading to failure or success in the creation of bile duct substitutes may help to develop more effective ***,the regeneration of a bile duct is delicately balanced between epithelialization and.s.bsequent submucosal maturation within limited time frames,which may be more apparent when using quantitative models to estimate ***,the utilization of the organism’s endogenous regeneration abilities may enhance the creation of bile duct *** are convinced that an interd.s.iplinary approach,including quantitative methods,machine learning,and deep retrospective analysis of the causes that led to success and failure in studies on the creation of bile duct substitutes,holds great ***,more attention should be directed towards the balance of epithelialization and.s.bmucosal maturation rates,as well as induced *** ideas d.s.rve further investigation to pave the way for bile duct restoration with physiologically relevant outcomes.

关键词： Bile duct alternative Bile duct substitute Regenerative medicine Regene rative surgery Theoretical surgery Quantitative human physiology

Making the link between AdF and 4d.s.EM:Resolution,transfer and coherence

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Chinese Physics B 2024年第11期33卷 26-33页

作者： peter d.Nellist Timothy J.Pennycook department of Materials University of OxfordOxfordUK EMAT University of AntwerpGroenenborgerlaan 1712020 AntwerpBelgium

steve Pennycook is a pioneer in the application of high-resolution scanning transmission electron microscopy(sTEM)and in particular the use of annular dark-field(AdF)*** we show how a general framework for 4d.s.EM allows clear links to be made between AdF imaging and the emerging methods for reconstructing images from 4d.s.EM data *** show that both AdF imaging and ptychographical reconstruction can be thought of in terms of integrating over the overlap regions of diffracted d.s.s in the detector *** approach allows the similarities in parts of their transfer functions to be understood,though we note that the transfer functions for ptychographic imaging cannot be used as a measure of information *** also show that conditions of partial spatial and temporal coherence affect AdF imaging and ptychography similarly,showing that achromatic interference can always contribute to the image in both cases,leading to a robustness to partial temporal coherence that has enabled high-resolution imaging.

关键词： image forming and processing phase retrieval electron microscopy scanning transmission electron microscope(sTEM)

Current hypotheses for the evolution of sex and recombination

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Integrative Zoology 2012年第2期7卷 192-209页

作者： Matthew HARTFIELd peter d.KEIGHTLEY Institute of Evolutionary Biology University of EdinburghEdinburghUK

The evolution of sex is one of the most important and controversial problems in evolutionary *** sex is almost universal in higher animals and plants,its inherent costs have made its maintenance difficult to ex*** most famous of these is the twofold cost of males,which can greatly reduce the fecundity of a sexual population,compared to a population of asexual *** the past century,multiple hypotheses,along with experimental evidence to support these,have been put forward to explain wid.s.read costly *** this review,we outline some of the most prominent theories,along with the experimental and observational evidence supporting ***,there have been 4 classes of theories:the ability of sex to fix multiple novel advantageous mutants(Fisher-Muller hypothesis);sex as a mechanism to stop the build-up of deleterious mutations in finite populations(Muller’s ratchet);recombination creating novel genotypes that can resist infection by parasites(Red Queen hypothesis);and the ability of sex to purge bad genomes if deleterious mutations act synergistically(mutational deterministic hypothesis).Current theoretical and experimental evidence seems to favor the hypothesis that sex breaks down selection interference between new mutants,or it acts as a mechanism to shuffle genotypes in order to repel parasitic ***,there is still a need to collect more data from natural populations and experimental studies,which can be used to test different hypotheses.

关键词： evolution of sex fitness-associated.s.x Hill-Robertson interference mutational deterministic hypothesis Red Queen hypothesis

Ecology of Pinnidae(Mollusca: Bivalvia) from the Gulf of Thailand

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Acta Oceanologica sinica 2019年第2期38卷 52-69页

作者： Cheewarat Printrakoon peter d Roopnarine Thamasak Yeemin Animal systematic special Unit Department of ZoologyFaculty of ScienceKasetsart University department of Invertebrate Zoology and Geology California Academy of Sciences department of Biology Faculty of ScienceRamkhamhaeng University

The ecology of the family Pinnidae was studied by sampling three pinnid.s.ecies from 36 sampling sites across four different microhabitats in the Gulf of Thailand. The species spatial d.s.ributions were mostly uniform, with some populations having random d.s.ributions. species abundances differed between sandy and coral habitats according to non-metric multi-dimension scaling analyses. Although the Gulf of Thailand is a relatively small geographic area, habitats are varied enough to provide variable shell densities. small islands are important d.s.ribution areas, and coral reefs provide both direct and indirect shelter which support high abundances,densities and increased.s.ell size. The highest density was recorded in sand beds within coral reefs. Low density and.s.all shell size in sand beaches might be related to high mortality in shallow water or to adaptations for survival in shallow waters. A clear correlation between sediment composition and.s.ecies abundance was found in Pinna atropurpurea; abundance increased with the sand content of the sediment. For P. deltod.s. abundance increased as the rock fraction of the sediment increased. These results suggest that adaptations in Pinnidae, such as shell size, shell morphology, and the exposure of the shell above the sediment-water interface, are responses for survival in different habitats.

关键词： density d.s.ribution pinnid shell shell adaptation the Gulf of Thailand

Making sense of Hospital Project MisPerformance: Over Budget, Late, Time and Time Again—Why? And What Can Be done About It?

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Engineering 2022年第5期8卷 183-201页

作者： peter E.d.Love Lavagnon A.Ika school of Civil and Mechanical Engineering Curtin UniversityPerthWA 6845Australia Telfer school of Management University of OttawaOttawaON KIN 6N5Canada

Hospital projects worldwide often experience misperformance,showing a tendency to exceed their estimated cost,miss their deadline,suffer quality problems,and yield benefit *** this ubiquitous problem,this paper aims to make sense of this phenomenon by addressing the following research question:How can we make sense of hospital project misperformance,and what can be done to mitigate its occurrence?We use an illustrative case study approach and the analytical lens of sense-making to examine the misperformance of three mega-hospital *** research reveals issues such as scope changes,an inability to adapt and respond to risk and uncertainty,ineffectual project management and governance,and optimism bias,which combine to impact project performance *** suggest that the two prominent theoretical perspectives dominating the literature in this field fall short of adequately explaining hospital project *** provide suggestions for improving the procurement process of hospitals and.s.bmit there is a need to develop a robust and balanced theory of project misperformance.

关键词： Cost Hospital Optimism bias Procurement Project management Performance sense-making

Novel ecosystems created by coal mines in central Queensland.s.Bowen Basin

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Ecological Processes 2013年第1期2卷 368-379页

作者： peter d Erskine Andrew T Fletcher Centre for Mined Land Rehabilitation The University of QueenslandBrisbane QLD 4072Australia

Introduction:Open-cut coal mining began in central Queensland.s.Bowen Basin approximately 50 years *** this period of time,mine rehabilitators have used a variety of tree,shrub,and groundcover species to create‘novel ecosystems’to stabilise soils and provide vegetative cover for pre-supposed final end-land *** examine post-mining rehabilitation from multiple soil and vegetation monitoring activities in the Bowen Basin to assess the similarity of landforms,plant composition,and trends in plant diversity compared to unmined reference ***:Rehabilitated.s.oil dumps and reference sites were assessed using soil and vegetation data contained in compliance monitoring reports from Goonyella Riverside,Moura,Oaky Creek,Rolleston,and Blackwater ***,soil chemistry,and plant species mixes of rehabilitation aged from 2 to 22 years were compared to selected reference ***:Mines in this region have generally proposed one of two post-rehabilitation end-land uses:either pasture for cattle grazing or reconstructed native communities which potentially provide native fauna *** data from a selection of these mine sites suggest that when their rehabilitation was compared to nearby reference sites median slope values were between 2.5 and 7 times steeper and.s.il pH,electrical conductivity,and phosphorus levels were significantly *** steeply sloped landforms,poor soil characteristics,depauperate native species pool,and uniform presence of exotic pasture grasses in the rehabilitation indicate that most of these newly created ecosystems should not be used for cattle grazing and also have few natural ***:Legislative and community expectations have changed progressively over time and,although much of the rehabilitation is currently dominated by an assemblage of exotic buffel grass(Cenchrus ciliaris)and Acacia spp.,recent environmental authorities suggest these‘novel ecosystems’will be judged against native refere

关键词： Coal mining Completion criteria Environmental conditions Novel ecosystems

Complementary Physical and Mechanical Techniques to Characterise Tooth: A Bone-like Tissue

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Journal of Bionic Engineering 2006年第1期3卷 19-31页

作者： peter Zioupos Keith d. Rogers Centre for Photo-manipulation and Photo-analysis of Materials Cranfield University Shrivenham SN 6 8LA UK Centre for Materials science and Engineering Cranfield University Postgraduate Medical School Shrivenham SN 6 8LA UK

Bone like tissues are biocomposites comprising an organic matrix （mostly collagen） and a reinforcement phase in the form of mineral crystals （poorly stoichiometric apatite）. The composite properties are a result of the material characteristics of the two phases, their interaction, the relative composition, the orientation and the micro-architecture of the structure. The inherent spatial heterogeneity of these tissues （a result of evolutionary and functional requirements） and their exposure to various environmental and mechanical influences result in highly variable properties on the microscale, which can only be characterised by modern microanalytical methods. We present here results obtained by the complementary use of the modem nanoindentation and micro-X-ray diffraction techniques, which were used to probe the properties and.s.ructure of human dentine and enamel of primary molar teeth. The results show that both the addition and the higher organization of mineral within the organic matrix produce stiffer and harder tissue and that the examination of properties within small tissue volumes can be reliably achieved by use of these two methods in parallel. This opens new avenues in the study of biomaterial in general, and for the local characterisation of regions of teeth that suffered bacterial attack, mechanical wear, fluorid.s.tion, chemical bleaching, or dental treatment such as laser ablation or drilling.

关键词： biogenic composites teeth nanoindentation hardness X-ray diffraction