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Science China(Technological Sciences) 2006年第4期49卷 445-456页

作者： Frank Dammel peter Stephan Chair of Technical Thermodynamics Darmstadt University of Technology Germany

An experimental investigation was conducted on the laminar flow frictional characteristics of suspensions with microencapsulated phase change material (mEPCm) in water flowing through rectangular copper minichannels. The mEPCm was provided at an average particle size of 4.97 μm, and was mixed with distilled water to form suspen- sions with various mass concentrations ranging from 0 to 20%. The experiment was per- formed to explore the effect of mEPCm mass concentration on friction factor and pressure drop in the minichannels. The Reynolds number ranged from 200 to 2000 to provide laminar and transitional flows. It was found that the experimental data for the suspensions with 0 and 5% concentration agree well with the existing theoretical data for an incom- pressible, fully developed, laminar Newtonian flow. For the suspensions with mass con- centrations higher than 10%, there is an obvious increase in friction factor and pressure drop in comparison with laminar Newtonian flow.

关键词： microencapsulated phase change material suspension, friction factor, rectangular minichannel.

PARALLEL STOCHASTIC NEWTON mETHOD

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Journal of Computational mathematics 2018年第3期36卷 404-425页

作者： mojmir mutny peter Richtarik Department of Informatics ETH Zurich Zurich Switzerland School of mathematics University of Edinburgh Edinburgh ETH9 3FD UK Computer Electrical and Mathematical Sciences & Engineering Department KA UST Saudi Arabia

We propose a parallel stochastic Newton method （PSN） for minimizing unconstrained smooth convex functions. We analyze the method in the strongly convex case, and give conditions under which acceleration can be expected when compared to its serial counterpart. We show how PSN can be applied to the large quadratic function minimization in general, and empirical risk minimization problems. We demonstrate the practical efficiency of the method through numerical experiments and models of simple matrix classes.

关键词： Optimization Parallel methods Newton's method Stochastic algorithms.

Overview of optical coherence tomography in neuro-ophthalmology

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Annals of Eye Science 2020年第2期5卷 26-43页

作者： Emanuel R.de Carvalho peter m.maloca moorfields Eye Hospital NHS Foundation Trust LondonUK Department of Ophthalmology University Medical Center AmsterdamUniversity of AmsterdamAmsterdamThe Netherlands Institute of molecular and Clinical Ophthalmology Basel(IOB) BaselSwitzerland OCTlab Department of OphthalmologyUniversity Hospital BaselBaselSwitzerland Department of Ophthalmology University of BaselBaselSwitzerland

Optical coherence tomography(OCT)is a widely used non-invasive medical imaging technology that has revolutionized clinical care in *** developments,such as OCT angiography(OCTA)are expected to contribute even further to the widespread use of OCT-based imaging devices in the diagnosis and monitoring of patients with ophthalmic *** recent years,many of the disadvantages such as limited field of view and imaging artefacts have been substantially *** to the progress achieved in the assessment of retinal disorders,OCT is expected to change the approach to patients seen in the neuro-ophthalmology *** this article,we review the technical features of OCT and OCT-based imaging techniques,highlighting the specific factors that should be taken into account when interpreting OCT in the field of neuro-ophthalmology.

关键词： Optic disc optical coherence tomography(OCT) angiography retina macula neuro-ophthalmology volume rendering virtual reality

Neurotransmitter systems in mouse airways

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中国药理学与毒理学杂志 2017年第10期31卷 1015-1016页

作者： peter W ABEL Cameron m KIEFFER Ya-ping TU Department of Pharmacology Creighton University School of Medicine

OBJECTIVE The objective of this study was to characterize the neurotransmitter systems that cause constriction of murine *** murine precision cut lung slices(PCLS)and trachea were prepared,placed into perfusion chambers equipped with platinum electrodes and stimulated transmurally(1.0 ms,50 V,0.1-30 Hz).To measure PCLS constriction,changes in airway luminal area in response to electric field stimulation(EFS)were captured as video images quantified using Image J *** trachea,changes in isometric tension were recorded using Grass force *** response curves were generated in the absence and the presence of the inhibitors magnesium,atropine and capsaicin and responses analyzed and compared using a student's t-test(Pmanner that was best fit by a biphasic ***-specific stimulation was verified by mg^(2+) *** airway constriction to 30 Hz EFS in PCLS was(51.8±3.0)%while tracheal constriction averaged(551±80)***,in PCLS the muscarinic receptor antagonist atropine(10μmol·L^(-1))blocked(99.5±7.2)%of EFS induced constriction at 1 Hz,but only blocked(23.3±3.8)%of EFS induced constriction at 30 Hz and eliminated the first phase but not the second phase of the biphasic EFS *** with capsaicin to deplete sensory neurotransmitters significantly increased EFS constriction supporting the presence of sensory neurotransmitter systems in *** These data are consistent with parasympathetic constriction of airways by acetylcholine at lower EFS frequencies while higher frequencies release sensory dilator *** data provide evidence for multiple nerve types innervating airways which may provide novel targets for treatment of lung disease.

关键词： airways nerve stimulation airway constriction atropine capsaicin

Idempotent Completions of Operator Partial matrices

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Acta mathematica Sinica,English Series 1999年第3期15卷 333-346页

作者： Heydar Radjavi peter Rosenthal Department of mathematics Shanxi Teachers University Linfen 041004 P. R. ChinaDepartment of Mathematics Statistics and Computing Science Dalhousie University Halifax N.S. B3H 3J5 Canada Department of mathematics University of Toronto Toronto On M5S 1A1 Canada

Necessary and sufficient conditions are obtained for operator partial 2×2 matrices to have an idempotent completion, and all such completions are parametrically represented.

关键词： Hilbert space Operator matrix Idempotent operator

Adaptation in brain structure and respiratory and olfactory structures across environmental gradients in African and North American muroid rodents

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Integrative Zoology 2024年第1期19卷 165-181页

作者： peter J.TAYLOR Aluwani NENGOVHELA Christiane DENYS Graham R.SCOTT Catherine m.IVY Department of Zoology School of Natural and Mathematical SciencesUniversity of VendaThohoyandouSouth Africa Afromontane Unit Department of Zoology and EntomologyUniversity of the Free StatePhuthaditjhabaSouth Africa Department of mammalogy National MuseumBloemfonteinSouth Africa Institut de Systématique EvolutionBiodiversité(ISYEB)Muséum National d’Histoire NaturelleCNRSSorbonne UniversitéEPHEUniversitéDes AntillesParisFrance Department of Biology McMaster UniversityHamiltonOntarioCanada Guglielmo and Shoemaker Labs Advanced Facility for Avian ResearchUniversity of Western OntarioLondonOntarioCanada

morphometric studies of 3D micro CT-scanned images can provide insights into the evolution of the brain and sensory structures but such data are still scarce for the most diverse mammalian order of *** reviewed and new data,we tested for convergence to extreme aridity and high elevation in the sensory and brain morphology of rodents,from morphometric data from micro-CT X-ray scans of 174 crania of 16 species of three distantly re-lated African murid(soft-furred mice,Praomyini,laminate-toothed rats,Otomyini,and gerbils,Gerbillinae)clades and one North American cricetid(deer mice and white-footed mice,Peromyscus)*** studies demon-strated convergent evolution acting on the oval window area of the cochlea(enlarged in extremely arid-adapted species of Otomyini and Gerbillinae)and on endocranial volume(reduced in high elevation taxa of Otomyini and Peromyscus).However,contrary to our predictions,we did notfind evidence of convergence in brain struc-ture to aridity,or in the olfactory/respiratory system(turbinate bones)to high *** structure differed,particularly in the petrosal lobules of the cerebellum and the olfactory bulbs,between Otomyini and Gerbillinae,with extreme arid-adapted species in each clade being highly divergent(not convergent)from other species in the same *** observed greater“packing”of the maxillary turbinate bones,which have important respiratory functions,in Peromyscus mice from high and low elevations compared to the high-elevation African Praomyini,but more complex patterns within Peromyscus,probably related to trade-offs in respiratory physiology and heat exchange in the nasal epithelium associated with high-elevation adaptation.

关键词： 3D morphometrics Africa brain size North America Rodentia sensory evolution

Non-Algorithmically Integrating Land Use Type with Spatial Interpolation of Surface Soil Nutrients in an Urbanizing Watershed

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Pedosphere 2017年第1期27卷 147-154页

作者： WU Qian LI Qingliang GAO Jinbo LIN Qiaoying XU Qiufang peter m.GROFFmAN YU Shen Key Laboratory of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021 China Zhejiang A&F University Lin'an 311300 China University of Chinese Academy of Sciences Beijing 100049 China Cary Institute of Ecosystem Studies Millbrook NY 12545(USA)

Integrating land use type and other geographic information within spatial interpolation has been proposed as a solution to improve the performance and accuracy of soil nutrient mapping at the regional scale. This study developed a non-algorithm approach, i.e., applying inverse distance weighting （IDW） and ordinary kriging （OK）, to individual land use types rather than to the whole watershed, to determine if this improved the performance in mapping soil total C （TC）, total N （TN）, and total P （TP） in a 200-km2 urbanizing watershed in Southeast China. Four land use types were identified by visual interpretation as forest land, agricultural land, green land, and urban land. One hundred and fifty soil samples （0-10 cm） were taken according to land use type and patch size. Results showed that the non-algorithm approach, interpolation based on individual land use types, substantially improved the performance of IDW and OK for mapping TC, TN, and TP in the watershed. Root mean square errors were reduced by 3.9% for TC, 10.770 for TN, and 25.9% for TP by the application of IDW, while the improvements by OK were slightly lower as 0.9% for TC, 7.7% for TN, and 18.1% for TP. Interpolations based on individual land use types visually improved depiction of spatial patterns for TC, TN, and TP in the watershed relative to interpolations by the whole watershed. Substantial improvements might be expected with denser sampling points. We suggest that this non-algorithm approach might provide an alternative to algorithm-based approaches to depict watershed-scale nutrient patterns.

关键词： geographic information system inverse distance weighting non-algorithm approach ordinary kriging spatial pattern

Apple dwarfing rootstocks exhibit an imbalance in carbohydrate allocation and reduced cell growth and metabolism

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Horticulture Research 2017年第1期4卷 311-323页

作者： Toshi m Foster peter A mcAtee Chethi N Waite Helen L Boldingh Tony K mcGhie The New Zealand Institute for Plant and Food Research Limited Palmerston North4474New Zealand The New Zealand Institute for Plant and Food Research Limited Auckland1142New Zealand The New Zealand Institute for Plant and Food Research Limited Hamilton3240New Zealand

Apple dwarfing rootstocks cause earlier shoot termination and reduced root and shoot *** identify physiological factors responsible for rootstock-induced growth restriction,we compared vascular-enriched gene expression between two dwarfing rootstocks(‘m27’and‘m9’)and the vigorous rootstock‘m793’using RNA sequencing and quantitative reverse transcriptase *** expressed genes common to both dwarfing rootstocks belonged to five main biological processes:(1)primary metabolism,(2)cell wall synthesis and modification,(3)secondary metabolism,(4)hormone signalling and response and(5)redox *** promoting the biosynthesis of amino acids,lipids and cell walls were downregulated in dwarfing rootstocks,whereas genes promoting the breakdown of these compounds were *** only exception to this trend was the upregulation of starch synthesis genes in dwarfing ***-structural carbohydrate analysis demonstrated that starch concentrations in‘m9’roots,stems and grafted‘Royal Gala’(‘RG’)scions were double that of equivalent tissues from‘RG’homo-grafted trees(‘RG’/‘RG’).Fructose and glucose concentrations were much lower in all three tissues of the‘RG’/‘m9’***,these data indicate that dwarfing rootstocks are in a state of sugar depletion and reduced cellular activity despite having large starch *** significant finding was the over-accumulation of flavonoids and the downregulation of auxin influx transporters mdAUX1 and mdLAX2 in dwarfing *** propose that both factors reduce polar auxin *** results of this study contribute novel information about the physiological state of dwarfing rootstocks.

关键词： walls roots dwarf

Exotic tree seedlings are much more competitive than natives but show underyielding when growing together

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Journal of Plant Ecology 2013年第4期6卷 305-315页

作者： Heike Kawaletz Inga mölder Stefan Zerbe peter Annighöfer André Terwei Christian Ammer Department of Silviculture and Forest Ecology of the Temperate Zones University of GöttingenBüsgenweg 137077 GöttingenGermany Energieagentur Region Göttingen e.V. Berliner Str.237073 GöttingenGermany Faculty of Science and Technology Free University of Bozen-BolzanoPiazza Università539100 BolzanoItaly

Aims Invasive species continue to be a worldwide threat to ecosystems mainly as a cause for biodiversity *** ecosystems,for example,are subject to a change in species composition due to the invasion of exotic *** the attributes that cause the strong competitiveness of several exotic species may improve the ability to understand and effectively manage plant invasions in the *** this study the following hypotheses were tested:(1)biomass production of below-and aboveground plant compo-nents of the exotic tree species is higher than that of the natives,resulting in a higher competitiveness of the exotics;(2)the exclu-sion of root competition has a positive effect on the biomass pro-duction of the inferior native species;and(3)mixtures of native and exotic species yield a higher biomass production than the respective *** a pot experiment,containing about 2000 tree seedlings,was *** investigated the biomass productivity and growth reactions of two native(Quercus robur l.,Carpinus betulus l.)and two exotic tree species(Prunus serotina Ehrh.,Robinia pseudoacacia l.)in different intra-and interspecific,competitive situations with and without the influence of root *** Findingsthe biomass production of both exotic species was significantly higher and led to a strong competitive advantage,resulting in a biomass decrease of the less competitive native *** high belowground biomass of both exotic species had a negative effect on the biomass *** competitive pressure of exotic tree seedlings on the native ones was largely driven by root ***,mixtures of native and exotic tree species had a higher productivity than their growth in monocultures would have *** was lower for exotic species in mixtures with the less productive native species compared to the competition in monocultures or in mixture with the other highly productive exotic ***,b

关键词： competition biomass production pot experiment invasive species Prunus serotina Robinia pseudoacacia

Effect of protective cultures on spoilage bacteria and the quality of vacuum-packaged lamb meat

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Food Bioscience 2022年第6期50卷 1615-1624页

作者： michelle m.Xu mandeep Kaur Christopher J.Pillidge peter J.Torley Biosciences and Food Technology School of ScienceRMIT UniversityPO Box 71BundooraVictoria3083Australia

Protective cultures,as natural antimicrobials,have the ability to suppress the growth of spoilage bacteria and can potentially be used to extend the shelf-life of fresh meat and help reduce food *** there have been limited reports on the application of this approach in fresh red meat,the aim of this study was to evaluate the potential and practicality of this approach for red meat shelf-life extension based on the antimicrobial efficacy and quality impact of selected protective *** protective cultures(one containing Lactobacillus sakei and the other containing Staphylococcus carnosus and ***)were applied to chill-stored(4°C)vacuum-packaged lamb meat to determine their effects on spoilage bacteria as well as non-microbiological meat quality over a 20-day storage *** protective cultures dominated the microbiota throughout storage and effectively suppressed the growth of common meat spoilage bacteria,Brochothrix thermosphacta,Pseudomonas spp.,and *** color(measured in CIE L*a*b*color space)changed slightly in culture-treated samples in the later stage of storage,but the changes were not unacceptable based on previously reported thresholds for consumer *** mixed culture containing additional *** exhibited a slightly stronger inhibitory effect against the spoilage bacteria but also caused more changes in meat *** culture addition did not significantly affect meat pH,texture,or ***,these results demonstrated the potential of biopreservation using protective cultures for fresh red meat shelf-life extension.

关键词： Biopreservation Natural antimicrobial Lactobacillus sakei Staphylococcus carnosus Fresh meat Shelf-life