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Giant pandas use odor cues to discriminate kin from nonkin

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Current Zoology 2016年第4期62卷 333-336页

作者： Oranit GILAD Ronald R. SWAISGOOD Megan A. owen Xiaoping ZHOU Department of Biology Texas A&M University College Station TX 77843 USA Institute for Conservation Research San Diego Zoo Global Escondido CA 92027 USA China Research and Conservation Center for the Giant Panda Wolong Sichuan 623006 China

Sociality is an important factor in both the mechanism and function of kin recognition, yet it is little explored in solitary species. While there may be future opportunities for nepotistic functions of kin discrimination among solitary species, the ability to discriminate kin from nonkin may still have important roles in social regulation. The solitary giant panda Ailuropoda melanoleuca offers a good model system to explore kin discrimination in a solitary mammal. As kin discrimination in many other mammals is olfactorily mediated, we investigated whether giant pandas are able to discriminate odor cues from daughters even after months and years of separation. Our results indicate that giant pandas are capable of discriminating between kin and nonkin using odor cues available in urine and body odor. Daughters preferentially investigated the odors of unrelated adult female pandas over the odors of their mothers, and mothers spent more time investigating the odors of unrelated age- matched female pandas over those from their daughters. Because these studies were conducted months or years after the mother-daughter period of dependency ended, it is still unclear what mechanism is used for recognition. Long-term olfactory memories and phenotype matching should both be considered, and further studies are required for such determination.

关键词： chemical communication giant panda kin discrimination.

EXPERIMENTAL AND NUMERICAL RESEARCH ON BULLDOZER WORKING PROCESS

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Chinese Journal of Mechanical Engineering 2007年第2期20卷 41-46页

作者： LI Yanjie XU Yong HUANG Wenbin FENG Y T owen D R J College of Science China Agricultural University Beijing 100083 China Civil ＆ Computational Engineering Center University of Wales Swansea Swansea SA2 8PP UK

A simulative analysis coupled with experiment on behaviors of a soil bed cut by a model bulldozer blade is carried out using the finite element/distinct element method（FE/DEM） facility built in the ELFEN package. Before simulation, tensile/compression, triaxial compression and the soil specimens are examined through uniaxial direct shear tests to obtain model characteristics and relevant parameters, then soil cutting experiments are carried out via a mini-soil bin system with a soil bed of 60/120 mm in width and 10 mm in depth cut by a 1/9 scale model bulldozer blade moving with the velocity of 10 mm/s. The soil constitutive model includes the tensile elastic model for tensile breakage and the compressive elastoplastic relationship with Mohr-Coulomb criterion. The cutting length in simulation is set as 1/4 of that in the experiment divided into 1 869 triangular elements. The comparison between the simulated results and experimental ones shows that the used model is capable of analyzing soil dynamic behaviors qualitatively, and the predicted fracturing profiles in general conform to the experiment. Hence the feasibility for analyzing soil fracturing behaviors in tillage or other similar processes is validated.

关键词： Finite element method Discrete element method Finite element/distinct element method(FE/DEM) Soil Bulldozer

Phytochemical characterization of polyphenolic compounds with HPLC–DAD–ESI–MS and evaluation of lipid-lowering capacity of aqueous extracts from Saharan plant Anabasis aretioides(Coss & Moq.) in normal and streptozotocin-induced diabetic rats

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Journal of Integrative Medicine 2018年第3期16卷 185-191页

作者： Omar Farid Farid Khallouki Morad Akdad Andrea Breuer Robert Wyn owen Mohamed Eddouks Team of Physiology & Endocrine Pharmacology Faculty of Sciences and Techniques Errachidia Moulay Ismail University Division of Preventive Oncology National Center for Tumor Diseases Im Neuenheimer Feld 460 German Cancer Research Center (DKFZ)

Objective： Anabasis aretioides （Coss ＆ Moq.）, a Saharan plant belonging to Chenopodiaceae family, is widely distributed in semi-desert areas from the Tafilalet region of Morocco. This plant is extensively used by local population against diabetes and cardiovascular disorders. The purpose of the study was to investigate the effect of the aqueous A. aretioides extract on lipid metabolism in normal and strepto-zotocin （STZ）-induced diabetic rats and to identify the polyphenolic compounds present. In addition, the in vitro antioxidant activity of the aqueous A. aretioides extract was also evaluated. Methods： The effect of an aerial part aqueous extract （APAE） ofA. aretioides （5 mg/kg of lyophilized A. are-tioides APAE） on plasma lipid profile was investigated in normal and STZ-induced diabetic rats （n = 6） after once daily oral administration for 15 days. The aqueous extract was tested for its 1,1-diphenyl-2-picrylhydrazyl （DPPH） radical-scavenging activity. Polyphenolic compounds in the extracts were defini-tively characterized by high-performance liquid chromatography-diode array detection-electrospray ionization-mass spectrometry. Results： In diabetic rats, oral administration ofA. aretioides APAE provoked a significant decrease in both plasma cholesterol and triglyceride levels from the first to the second week （P 〈 0.01）. A significant decrease on plasma triglyceride levels was also observed in normal rats （P 〈 0.01）, where the reduction was 53%. In addition, the phytochemical analysis revealed the presence of 12 polyphenolic compounds. Moreover, according to the DPPH radical-scavenging activity, the aqueous extract showed an in vitro antioxidant activity. Conclusion： Aqueous A. aretioides APAE exhibits lipid-lowering and in vitro antioxidant activities. Many polyphenols were present in this extract and these phytoconstituents may be involved in the pharmaco-logical activity of this plant.

关键词： Anabasis aretioides 1,1-Diphenyl-2-picrylhydrazyl Antioxidant activity Phytochemical analysis Lipid metabolism Polyphenolic compounds

Quantifying geological uncertainty in metamorphic phase equilibria modelling;a Monte Carlo assessment and implications for tectonic interpretations

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Geoscience Frontiers 2016年第4期7卷 591-607页

作者： Richard M.Palin owen M.Weller David J.Waters Brendan Dyck Institute of Geosciences Johannes-Gutenberg University Mainz55128MainzGermany Geological Survey of Canada 601 Booth StreetOttawaONKIA OESCanada Department of Earth Sciences University of OxfordOxfordOX1 3ANUnited Kingdom

Pseudosection modelling is rapidly becoming an essential part of a petrologist＇s toolkit and often forms the basis of interpreting the tectonothermal evolution of a rock sample, outcrop, or geological region. Of the several factors that can affect the accuracy and precision of such calculated phase diagrams, ＂geological＂ uncertainty related to natural petrographic variation at the hand sample- and/or thin section-scale is rarely considered. Such uncertainty influences the sample＇s bulk composition, which is the primary control on its equilibrium phase relationships and thus the interpreted pressure-temper- ature （P-T） conditions of formation. Two case study examples--a garnet-cordierite granofels and a garnet-staurolite-kyanite schist--are used to compare the relative importance that geological uncer- tainty has on bulk compositions determined via （1） X-ray fluorescence （XRF） or （2） point counting techniques. We show that only minor mineralogical variation at the thin-section scale propagates through the phase equilibria modelling procedure and affects the absolute P-T conditions at which key assemblages are stable. Absolute displacements of equilibria can approach ＋l kbar for only a moderate degree of modal proportion uncertainty, thus being essentially similar to the magnitudes reported for analytical uncertainties in conventional thermobarometry. Bulk compositions determined from multiple thin sections of a heterogeneous garnet-staurolite-kyanite schist show a wide range in major-element oxides, owing to notable variation in mineral proportions. Pseudosections constructed for individual point count-derived bulks accurately reproduce this variability on a case-by-case basis, though averaged proportions do not correlate with those calculated at equivalent peak P-T conditions for a whole-rock XRF-derived bulk composition. The main discrepancies relate to varying proportions of matrix phases （primarily mica） relative to porphyroblasts （primarily staurolite and kyanit

关键词： Geological uncertainty Error Pseudosection Monte Carlo MnNCKFMASHTO

Phenotypic plasticity in rice:responses to fertilization and inoculation with arbuscular mycorrhizal fungi

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Journal of Plant Ecology 2016年第1期9卷 107-116页

作者： Shujuan Zhang Li Wang Fang Ma Jixian Yang owen K.Atkin State Key Laboratory of Urban Water Resource and Environment School of Municipal and Environmental EngineeringHarbin Institute of Technology73 Huanghe RoadNangang DistrictHarbin 150090China ARC Centre of Excellence in Plant Energy Biology Division of Plant SciencesResearch School of BiologyThe Australian National UniversityBuilding 134Sullivans Creek RoadCanberraAustralian Capital Territory 2601Australia

Aims Changes in the phenotype of crops(phenotypic plasticity)are known to play an important role in determining responses to nutrient availability,with the direction and magnitude of plasticity of individual traits being crucial for grain *** study analysed the direction,magnitude and hierarchy of plastic responses of yieldrelated traits(*** allocation and yield components)of rice(Oryza sativa L.)to nutrient *** estimated the effect of inoculation with arbuscular mycorrhizal fungi(AMF)on these characteristics of phenotypic *** A field experiment was carried out in northeast China,providing rice with six NPK fertilizer levels with or without inoculation with Glomus *** maturity,we quantified biomass allocation traits(shoot:root ratio and panicle:shoot ratio)and yield component traits(panicle number per hill,spikelet number per panicle,percentage of filled spikelets and seed weight).We also assessed the direction of change in each trait and the magnitude of trait *** Findings In non-inoculated plants,we found that biomass allocation and seed-number traits(*** number per hill,spikelet number per panicle and percentage of filled spikelets)responded to fertilization in the same direction,increasing with rising *** formation was the most plastic trait,while seed mass was the least plastic *** inoculation nullified the relationship between most biomass allocation and seed-number traits(except for that between panicle:shoot ratio and the percentage of filled spikelets)but increased the magnitude of plasticity in biomass allocation traits without altering the hierarchy of traits’*** results underscore the importance of plasticity of yield-related traits per se,and the impact of AMF on plasticity,for maintaining rice yields under low fertilization regimes.

关键词： fertilization plastic response rice nutrient availability symbiosis

Modelling of Magnetorheological Fluids with Combined Lattice Boltzmann and Discrete Element Approach

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Communications in Computational Physics 2010年第5期7卷 1095-1117页

作者： K.Han Y.T.Feng D.R.J.owen Civil and Computational Engineering Centre School of EngineeringSwansea UniversitySA28PPUK

A combined lattice Boltzmann and discrete element approach is proposedfor numerical modelling of magnetorheological fluids. In its formulation, the particledynamics is simulated by the discrete element method, while the fluid field is resolvedwith the lattice Boltzmann method. The coupling between the fluid and the particlesare realized through the hydrodynamic interactions. Procedures for computing magnetic, contact and hydrodynamic forces are discussed in detail. The applicability ofthe proposed solution procedure is illustrated via a two-stage simulation of a MR fluidproblem with four different particle volume fractions. At the first stage, simulationsare performed for the particle chain formation upon application of an external magnetic field;and at the second stage, the rheological properties of the MR fluid underdifferent shear loading conditions are investigated with the particle chains establishedat the first stage as the initial configuration.

关键词： Magnetorheological fluids particle dynamics rheological properties magnetic interaction models lattice Boltzmann method discrete element method

Astrometric calibration and source characterisation of the latest generation neuromorphic event-based cameras for space imaging

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Astrodynamics 2023年第4期7卷 415-443页

作者： Nicholas owen Ralph Alexandre Marcireau Saeed Afshar Nicholas Tothill Andre van Schaik Gregory Cohen International Centre for Neuromorphic Systems MARCS Institute for BrainBehaviour and DevelopmentWestern Sydney UniversityKingswood 2747NSWAustralia

As an emerging approach to space situational awareness and space imaging,the practical use of an event-based camera(EBC)in space imaging for precise source analysis is still in its *** nature of event-based space imaging and data collection needs to be further explored to develop more effective event-based space imaging systems and advance the capabilities of event-based tracking systems with improved target measurement ***,for event measurements to be meaningful,a framework must be investigated for EBC calibration to project events from pixel array coordinates in the image plane to coordinates in a target resident space object’s reference *** this paper,the traditional techniques of conventional astronomy are reconsidered to properly utilise the EBC for space imaging and space situational *** paper presents the techniques and systems used for calibrating an EBC for reliable and accurate measurement *** techniques are vital in building event-based space imaging systems capable of real-world space situational awareness *** calibrating sources detected using the EBC,the spatiotemporal characteristics of detected sources or“event sources”can be related to the photometric characteristics of the underlying astrophysical ***,these characteristics are analysed to establish a foundation for principled processing and observing techniques which appropriately exploit the capabilities of the EBC.

关键词： neuromorphic event-based camera(EBC) space imaging space situational awareness(SSA) astronomy

CD44 and CD221 directed magnetic cubosomes for the targeted delivery of helenalin to rhabdomyosarcoma cells

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Nano Research 2023年第2期16卷 2915-2926页

作者： Hakmin Mun Yuriy Chaban Tanveer A.Tabish Nanasaheb Thorat Nathan Cowieson CDavid owen Helen E.Townley Nuffield Department of Women’s and Reproductive health University of OxfordOxford OX39DUUK Electron Bio-Imaging Centre Diamond Light SourceDidcot OX110DEUK Radcliffe Department of Medicine University of OxfordOxford OX37BNUK B21 Diamond Light SourceDidcot OX110DEUK Department of Engineering Science University of OxfordOxford OX13PJUK

Confining chemotherapy to tumour sites by means of active targeting nanoparticles(NPs)may increase the treatment effectuality while reducing potential side *** are one of the next-generation drug delivery nanocarriers by virtue of their biocompatibility and bioadhesion,sizeable payload encapsulation and high ***,an active tumour targeting system towards rhabdomyosarcoma(RMS)cells was *** were loaded with helenalin(a secondary metabolite from Arnica plants),which we have previously shown to induce apoptosis in RMS *** functionalization of the cubosomes was accomplished to enable binding to membrane receptors and translocation under a magnetic *** cells overexpress CD44 and CD221 on their membrane surface and,therefore,hyaluronic acid(HA,a ligand for CD44)and antibodies(Abs)against CD221 were coupled to cubosomes via electrostatic attraction and the thiol-Michael reaction,*** of the cubic phase NPs was achieved by embedding superparamagnetic iron oxide NPs(SPIONPs)into the cubic ***-function and multi-function cubosomes had Im3m cubic phase structures with well-organized lattice *** with 2%HA or anti-CD221 half Abs and/or 1%SPIONPs showed significantly higher uptake into RMS cells compared to unfunctionalized ***44 and CD221 directed magnetic(triple-function)cubosomes were capable of internalizing into RMS cells in an energy-independent ***-laden triple functionalized cubosomes showed limited impact on the viability of control fibroblast cells,while they induced a high degree cytotoxicity against RMS *** tumour cell death was observed in both two-dimensional(2D)culture and three-dimensional(3D)tumour spheroids.

关键词： cubosome active targeting rhabdomyosarcoma helenalin nanoparticle functionalization

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