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The Siberian Traps and the End-Permian mass extinction:a critical review

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Chinese Science Bulletin 2009年第1期54卷 20-37页

作者： Andy saunders Marc REICHOW Department of Geological Sciences University of Leicester

The association between the Siberian Traps,the largest continental flood basalt province,and the largest-known mass extinction event at the end of the Permian period,has been strengthened by re-cently-published high-precision 40Ar/39Ar dates from widespread localities across the Siberian prov-ince[1]. We argue that the impact of the volcanism was amplified by the prevailing late Permian envi-ronmental conditions―in particular,the hothouse climate,with sluggish oceanic circulation,that was leading to widespread oceanic anoxia. Volcanism released large masses of sulphate aerosols and carbon dioxide,the former triggering short-duration volcanic winters,the latter leading to long-term warming. Whilst the mass of CO2 released from individual eruptions was small compared with the total mass of carbon in the atmosphere-ocean system,the long ‘mean lifetime’ of atmospheric CO2,com-pared with the eruption flux and duration,meant that significant accumulation could occur over periods of 105 years. Compromise of the carbon sequestration systems (by curtailment of photosynthesis,de-struction of biomass,and warming and acidification of the oceans) probably led to rapid atmospheric CO2 build-up,warming,and shallow-water anoxia,leading ultimately to mass extinction.

关键词：西伯利亚二叠纪温室气候海洋缺氧 CO2 SO2

Evaluating Land Use and Emergency Management Plans for Natural Hazards as a Function of Good Governance:A Case Study from New Zealand

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International Journal of Disaster Risk Science 2015年第1期6卷 62-74页

作者： Wendy saunders Emily Grace James Beban David Johnston GNS Science School of Psychology Massey University Joint Centre of Disaster ResearchMassey University

Plan evaluation is of utmost importance as a function of good governance. It provides a means to improve the institutional basis for implementing land use controls, provides an important opportunity to improve future plans to reduce risk, and improves the vision for sustainable development and management. This article provides an overview of the methods and findings of a plan evaluation project undertaken in New Zealand. The project analyzed 99 operative plans, provided in-depth analysis of ten plans, and included a capability and capacity study of councils. This is the first time all operative plans in New Zealand have had their natural hazard provisions assessed in this manner. The information provides an important baseline for future policy improvements, and a basis for future research and policy directions. The project found that, while New Zealand land use plans appear to be improving over time, there are still opportunities for improvement. These include improving linkages between objectives, policies, and rules within land use plans; and strengthening the linkages between land use and emergency management plans. The largest challenge is the accessibility, understanding of, and updating of hazard information.

关键词： Emergency management plans Land use plans Natural hazards New Zealand Plan evaluation

Defining the effect of sweep tillage tool cutting edge geometry on tillage forces using 3D discrete element modelling

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Information Processing in Agriculture 2015年第2期2卷 130-141页

作者： Mustafa Ucgul John M.Fielke Chris saunders Barbara Hardy Institute School of EngineeringUniversity of South AustraliaMawson LakesSA 5095Australia

The energy required for tillage processes accounts for a significant proportion of total energy used in crop *** many tillage processes decreasing the draft and upward vertical forces is often desired for reduced fuel use and improved penetration,*** studies have proved that the discrete element modelling(DEM)can effectively be used to model the soil–tool *** his study,Fielke(1994)[1]examined the effect of the various tool cutting edge geometries,namely;cutting edge height,length of underside rub,angle of underside clearance,on draft and vertical *** this paper the experimental parameters of Fielke(1994)[1]were simulated using 3D discrete element modelling *** the simulations a hysteretic spring contact model integrated with a linear cohesion model that considers the plastic deformation behaviour of the soil hence provides better vertical force prediction was *** parameters were determined by comparing the experimental and simulation results of angle of repose and penetration *** results of the study showed that the simulation results of the soil-various tool cutting edge geometries agreed well with the experimental results of Fielke(1994)[1].The modelling was then used to simulate a further range of cutting edge geometries to better define the effect of sweep tool cutting edge geometry parameters on tillage *** extra simulations were able to show that by using a sharper cutting edge with zero vertical cutting edge height the draft and upward vertical force were further reduced indicating there is benefit from having a really sharp cutting *** extra simulations also confirmed that the interpolated trends for angle of underside clearance as suggested by Fielke(1994)[1]where correct with a linear reduction in draft and upward vertical force for angle of underside clearance between the ranges of-25 and-5°,and between-5 and 0°.The good correlations give confidence to recommend further invest

关键词： DEM Cutting edge geometry

Mechanical behavior predictions of additively manufactured microstructures using functional Gaussian process surrogates

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npj Computational Materials 2021年第1期7卷 720-730页

作者： Robert saunders Celia Butler John Michopoulos Dimitris Lagoudas Alaa Elwany Amit Bagchi US Naval Research Laboratory WashingtonDCUSA Texas A&M University College StationTXUSA Synopsys Northern Europe Ltd ExeterUK University of Exeter ExeterUK

Relational linkages connecting process,structure,and properties are some of the most sought after goals in additive manufacturing(AM).This is desired especially because the microstructural grain morphologies of AM components can be vastly different than their conventionally manufactured ***,data collection at the microscale is ***,this work describes and demonstrates a methodology to link microstructure morphology to mechanical properties using functional Gaussian process surrogate models in a directed graphical network capable of achieving near real-time property predictions with single digit error magnitudes when predicting full stress–strain histories of a given *** methodology is presented and demonstrated using computationally generated microstructures and results from crystal plasticity simulations on those *** surrogate model uses grain-level microstructural descriptors rather than whole microstructure descriptors so that properties of new,arbitrary microstructures can be *** developed network has the potential to scale to predict mechanical properties of grain structures that would be infeasible to simulate using finite element methods.

关键词： grain microstructure additive

A review of electromagnetic processing of materials(EPM):Heating,sintering,joining and forming

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Journal of Materials Science & Technology 2021年第10期69卷 239-272页

作者： Mattia Biesuz Theo saunders Daoyao Ke Michael J.Reece Chungfeng Hu Salvatore Grasso Southwest Jiaotong University School of Materials Science and EngineeringChengdu 611756China Queen Mary University of London Mile End Road.El 4NS LondonUK University of Trento Department of Industrial EngineeringVia Sommarive 938123 TrentoItaly

Electricity is an efficient form of energy,and the growing interest in electricity-assisted manufacturing is motivated by its inherent energy saving and reduced environmental *** this,Electromagnetic Processing of Materials(EPM)allows the fabrication of materials with new compositions,metastable phases and nanograined microstructures that cannot be obtained using conventional heating processes using *** review covers EPM for the manufacture of ceramic and metal bulk components,with a specific focus on the effects of electric fields and electromagnetic radiations on processing in a wide spectrum of frequencies ranging from DC(f=0 Hz)to visible light(f=10^(14)–10^(15)Hz).The manuscript is divided into two *** first part provides a comprehensive overview of the interactions between matter and electric field/current,including heating phenomena(resistive Joule,induction,dielectric heating,electric arcs)and athermal effects(electromigration,electroplasticity,electrochemical reactions,ponderomotive force and others).The second part is focused on the technological application of the techniques,covering heat treatments,joining,sintering and *** distinct physical phenomena are involved in EPM:resistive Joule and induction heating,electrochemical reactions,electroplasticity,electric arcs and electromagnetic heating based on radio and microwave frequencies(mainly used for heating dielectric materials;i.e.,dielectric heating)or on the IR/visible light(IR heating and lasers).

关键词： Field-assisted sintering Electroplasticity Joining Welding Induction heating Arc melting

Progress Toward Implementing the Sendai Framework, the Paris Agreement, and the Sustainable Development Goals: Policy from Aotearoa New Zealand

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International Journal of Disaster Risk Science 2020年第2期11卷 190-205页

作者： Wendy S.A.saunders Scott Kelly Suzanne Paisley Larissa B.Clarke GNS Science Lower Hutt 5010New Zealand

In 2015, Aotearoa New Zealand became a signatory to the Sendai Framework for Disaster Risk Reduction 2015–2030(Sendai Framework), the Paris Climate Change Agreement(Paris Agreement), and the Sustainable Development Goals(SDGs). Since 2017 Aotearoa New Zealand has been undergoing governance reform to realign priorities and to improve the management of natural hazards and climate change. The aim of this article is to provide a review of how Aotearoa New Zealand is taking steps to improve consistency of planning across the legislative environment, thereby implementing its commitments to the Sendai Framework, the SDGs, and the Paris Agreement. It provides an overview of the national governance arrangements, with a focus on the key legislative tools;identifies how key terms are defined nationally;and provides an overview of the governance arrangements that contribute to the country’s international obligations. The discussion describes how obligations are applied, and considers two"disruptive and proactive" action examples. Four recommended actions are provided to further implement these international aspirations:(1) take into account these international agreements during the development and implementation of all legislation;(2) build awareness, capability,and capacity within central, regional, and local governments to support implementation;(3) actively evaluate the progress of implementing initiatives designed to reduce vulnerability and strengthen resilience;and(4) ensure that more weight and value are given to indigenous planning documents.

关键词： Disaster risk resilience Living standards framework Natural hazard vulnerability New Zealand Sustainable development goals National wellbeing

Social interactivity in pigeon courtship behavior

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Current Zoology 2017年第1期63卷 85-95页

作者： Emma L.R. WARE Daniel R. saunders Nikolaus F, TROJE Department of Psychology Queen's University Kingston Ontario K7L 3N6 Canada Centre for Neuroscience Studies Queen's University Kingston Ontario K7L 3N6 Canada Wellesley Institute Toronto Ontario M4V 3B Canada Centre for Brain/Mind Sciences University of Trento Trento Italy Department of Biology Queen's University Kingston K7L 3N6 Canada

A closed-loop teleprompter system was used to isolate and manipulate social interactivity in thenatural courtship interactions of pigeons Columbia livia. In Experiment 1, a live face-to-face real-time interaction between 2 courting pigeons （Live） was compared to a played back version of thevideo stimulus recorded during the pairs Live interaction. We found that pigeons were behavinginteractively; their behavior depended on the relationships between their own signals and those oftheir partner. In Experiment 2, we tested whether social interactivity relies on spatial cues presentin the facing direction of a partner＇s display. By moving the teleprompter camera 90~ away from itsoriginal location, the partner＇s display was manipulated to appear as if it is directed 90~ away fromthe subject. We found no effect of spatial offset on the pigeon＇s behavioral response. In Experiment3, 3 time delays, 1 s, 3s, and 9s, a Live condition, and a playback condition were chosen to investi-gate the importance of temporal contiguity in social interactivity. Furthermore, both opposite-sex（courtship） and same-sex （rivalry） pairs were studied to investigate whether social-context affectssocial interactivity sensitivity. Our results showed that pigeon courtship behavior is sensitive totemporal contiguity. Behavior declined in the 9 s and Playback conditions as compared to Live con-dition and the shorter time delays. For males only, courtship behavior also increased in the 3-sdelay condition. The effect of social interactivity and time delay was not observed in rivalry inter-actions, suggesting that social interactivity may be specific to courtship.

关键词： courtship behavior, pigeons, social interactivity, spatial offset, time delay, video playback.

Biomimetic delivery of signals for bone tissue engineering

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Bone Research 2018年第3期6卷 205-216页

作者： Ming Dang Laura saunders Xufeng Niu Yubo Fan Peter X.Ma Macromolecular Science and Engineering Center University of Michigan Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education School of Biological Science and Medical Engineering Beihang University Beijing Advanced Innovation Center for Biomedical Engineering Beihang University Department of Biologic and Materials Sciences University of Michigan Department of Biomedical Engineering University of Michigan Department of Materials Science and Engineering University of Michigan

Bone tissue engineering is an exciting approach to directly repair bone defects or engineer bone tissue for *** play a pivotal role in providing a template and extracellular environment to support regenerative cells and promote tissue regeneration. A variety of signaling cues have been identified to regulate cellular activity, tissue development, and the healing process. Numerous studies and trials have shown the promise of tissue engineering, but successful translations of bone tissue engineering research into clinical applications have been limited, due in part to a lack of optimal delivery systems for these signals. Biomedical engineers are therefore highly motivated to develop biomimetic drug delivery systems, which benefit from mimicking signaling molecule release or presentation by the native extracellular matrix during development or the natural healing process. Engineered biomimetic drug delivery systems aim to provide control over the location, timing, and release kinetics of the signal molecules according to the drug's physiochemical properties and specific biological mechanisms. This article reviews biomimetic strategies in signaling delivery for bone tissue engineering, with a focus on delivery systems rather than specific molecules. Both fundamental considerations and specific design strategies are discussed with examples of recent research progress, demonstrating the significance and potential of biomimetic delivery systems for bone tissue engineering.

关键词： exciting approach therefore highly motivated

Panorama of boron nitride nanostructures via lamp ablation

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Nano Research 2019年第3期12卷 557-562页

作者： Sehrina Eshon Weike Zhang Martin saunders Yujun Zhang Hui Tong Chua Jeffrey M. Gordon Department of Chemical Engineering The University of Western Australia Perth WA 6009 Australia Centre for Microscopy Characterisation and Analysis The University of Western Australia Perth WA 6009 Australia School of Environmental Science and Engineering Taiyuan University of Technology Taiyuan 030024 China Department of Material Science and Engineering Shandong University Jinan 250061 China Department of Solar Energy and Environmental Physics Blaustein Institutes far Desert Research Bert-Gurion University of the Negev Sede Boqer Campus 8499000 Israel

A diverse range of remarkable boron n itride (BN) nano structures subsumi ng nano-homs, nano-rods, nano-platelets, and clusters of hollow nano spheres (nano-onions, arguably of greatest applied and fun damental in terest) have bee n produced exclusively from crystalline BN precursor powder via lamp ablation. The procedure is safe, devoid of toxic reagents, simple, rapid and scalable—generating some genres of nan oparticles that had previously proved elusive. Product structure and composition were unambiguously assessed by high-resoluti on transmission electron microscopy, energy-dispersive X-ray spectroscopy and electron energy loss spectroscopy.

关键词： Aboron nitride nanostructures nano-onions lamp ablation non-toxic