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Coastal life is not under threat by the carbon dioxide emissions

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Journal of Coastal Life Medicine 2014年第3期 239-252页

作者： albert parker School of Aerospace Mechanical and Manufacturing Engineering RMIT UniversityBundooraVICAustralia

The near future of coastal life is threated by the claim of global warming alarmist that sea levels will rise by one to seven metres by 2100,destroying many coastal cities and *** paper shows that sea levels will more likely rise no more than just a few centimetres during this century as the Earth defrosts from the Little Ice Age 500 years ago with a mild warming.

关键词： Sea level rate of rise Sea level accelerations Tide gauge measurements Global mean sea level reconstructions

Deformations of Land,Sea and Gravity Levels by the 2009 Samoa Earthquake

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International Journal of Geosciences 2018年第10期9卷 579-592页

作者： Nils-Axel Morner albert parker Pamela Matlack-Klein Paleogeophysics&Geodynamics StockholmSweden Independent Scientist BandooraAustralia The Portuguese Sea Level Project PortoPortugal

The Samoa Islands were struck by the September 2009 earthquake of Mw 8.1. We study the effect on the land level by means of GPS monitoring and on ocean level by tide-gauge records. This allows us to present a new picture of the interaction of crustal movements, gravitational adjustment and sea level changes. The land level exhibits a co-seismic uplift followed by a post-seismic crustal subsidence. The ocean level records a fall, significantly larger than the uplift and delayed by several months, followed by a significant rise, by far exceeding the crustal subsidence and delayed by several months. This indicates a significant contribution from changes in gravity (geoidal eustasy), besides relative sea level changes due to crustal movements. High amplitude, and high frequency changes in tidal range provide evidence of changes in gravity and geoidal eustasy.

关键词： The Samoa Islands 2009 Earthquake and Tsunami GPS Records Tide-Gauge Stationas at Apia and Pago Pago Short-Term Gravity Changes

The functional properties of synapses made by regenerated axons across spinal cord lesion sites in lamprey

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Neural Regeneration Research 2022年第10期17卷 2272-2277页

作者： David parker Department of Physiology Developmentand NeuroscienceUniversity of CambridgeCambridgeUK

While the anatomical properties of regenerated axons across spinal cord lesion sites have been studied extensively,little is known of how the functional properties of regenerated synapses compared to those in unlesioned *** study aims to compare the properties of synapses made by regenerated axons with unlesioned axons using the lamprey,a model system for spinal injury research,in which functional locomotor recovery after spinal cord lesions is associated with axonal regeneration across the lesion *** synapses below the lesion site did not differ from synapses from unlesioned axons with respect to the amplitude and duration of single excitatory postsynaptic *** also showed the same activity-dependent depression over spike ***,regenerated synapses did differ from unlesioned synapses as the estimated number of synaptic vesicles was greater and there was evidence for increased postsynaptic quantal *** axons above the lesion site,the amplitude and duration of single synaptic inputs also did not differ significantly from unlesioned ***,in this case,there was evidence of a reduction in release probability and inputs facilitated rather than depressed over spike *** inputs from single regenerated axons below the lesion site thus do not increase in amplitude to compensate for the reduced number of descending axons after functional ***,the postsynaptic input was maintained at the unlesioned level using different synaptic ***,the facilitation from the same initial amplitude above the lesion site made the synaptic input over spike trains functionally *** may help to increase propriospinal activity across the lesion site to compensate for the lesion-induced reduction in supraspinal *** animal experiments were approved by the Animal Ethics Committee of Cambridge University.

关键词： electrophysiology lamprey plasticity regeneration reticulospinal axon spinal cord spinal injury synapse

Positron emission particle tracking——Application and labelling techniques

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Particuology 2008年第1期6卷 16-23页

作者： David J. parker School of Physics and Astronomy the University of Birmingham Edgbaston Birmingham B15 2TT UK

The positron emission particle tracking （PEPT） technique has been widely used in science and engineering to obtain detailed information on the motion and flow fields of fluids or granular materials in multiphase systems, for example, fluids in rock cracks, chemical reactors and food processors; dynamic behaviour of granular materials in chemical reactors, granulators, mixers, dryers, rotating kilns and ball mills. The information obtained by the PEPT technique can be used to optimise the design, operational conditions for a wide range of industrial process systems, and to evaluate modelling work. The technique is based on tracking radioactively labelled particles （up to three particles） by detecting the pairs of backto-back 511 keV γ-rays arising from annihilation of emitted positrons. It therefore involves a positron camera, location algorithms for calculating the tracer location and speed, and tracer labelling techniques. This paper will review the particle tracking technique from tracking algorithm, tracer labelling to their application.

关键词： PEPT Tracer Algorithm Tracking

A collaboration into research on nanoparticles (ACORN)

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Particuology 2009年第2期7卷 93-105页

作者： David G. parker Chemistry Innovation The HeathRuncorn WA7 4QXUnited Kingdom

This paper describes the operation and outcome of one of the United Kingdom＇s largest multi-partner research activities in nanoparticles. The research covers the discovery and development of organic and inorganic crystals/nanoparticles, nanoparticle properties towards specific product applications. The research also encompassed bespoke measurement technology for nanoparticles and structure interactions. Significant research outcomes are summarised. The paper illustrates the advantages from industrially motivated research and value of collective action between a broad group of researchers in a nation.

关键词： Nanoparticles Nanoparticle manufacture Nanocrystals Nanoassembly structure Modelling

Functional changes after spinal lesions: implications for interventions

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Neural Regeneration Research 2018年第5期13卷 811-812页

作者： David parker Department of Physiology Neuroscience and DevelopmentUniversity of Cambridge

We have known for many years that the spinal cord can generate some basic locomotor outputs under specific experimental conditions without any input from the brain or the periphery（Stuart and Hultborn,2008）.However,when inputs from the brain are lost following spinal cord injury（SCI）,the mammalian spinal cord is unable to generate normal,goal-directed locomotor outputs.

关键词： Functional changes after spinal lesions implications for interventions

The ethical cost of doing nothing

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National Science Review 2020年第7期7卷 1260-1262页

作者： Andrew J.parker University of Oxford Department of PhysiologyAnatomy and Genetics

Concern has been raised about the ethics and risks of performing genetic interventions in macaque monkeys to study models of human neuropsychiatric conditions. Here I point out that,when the outcome of some situations is truly uncertain, human decision makers tend to evaluate these situations inconsistently. The consequences of this inconsistency are sometimes profound, as they lead policy makers and reviewers to ignore or discount the ethical costs of doing nothing. I conclude that there are fundamental problems with the ‘precautionary

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Strong Laws of Large Numbers for Double Sums of Banach Space Valued Random Elements

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Acta Mathematica Sinica,English Series 2019年第5期35卷 583-596页

作者： Robert parker Andrew ROSALSKY Department of Biostatistics University of Florida Department of Statistics University of Florida

For a double array {V_(m,n), m ≥ 1, n ≥ 1} of independent, mean 0 random elements in a real separable Rademacher type p(1 ≤ p ≤ 2) Banach space and an increasing double array {b_(m,n), m ≥1, n ≥ 1} of positive constants, the limit law ■ and in L_p as m∨n→∞ is shown to hold if ■ This strong law of large numbers provides a complete characterization of Rademacher type p Banach spaces. Results of this form are also established when 0 < p ≤ 1 where no independence or mean 0 conditions are placed on the random elements and without any geometric conditions placed on the underlying Banach space.

关键词： Real separable Banach space double array of independent random elements strong law of large numbers almost sure convergence Rademacher type p Banach space convergence in Lp

Reminiscing my sixty year pursuit of the physics of the Sun and the Galaxy

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Research in Astronomy and Astrophysics 2014年第1期14卷 1-14页

作者： Eugene N.parker Department of Physics Department of Astronomy and AstrophysicsUniversity of Chicago

Reminiscing begins with childhood and passes on to student days through graduate school and the first real contact with research. Then early academic posi- tions and stumbling efforts to pursue my ideas. The first significant progress came as a research associate with Prof. W. M. Elsasser at the University of Utah, beginning with an introduction to magnetohydrodynarnics and the generation of the geomagnetic field through induction in the liquid metal core of Earth. A move to the University of Chicago to work with Prof. J. A. Simpson, on the implications of cosmic ray varia- tions and interplanetary magnetic fields, led to the theory of coronal expansion and the solar wind and then to exploring the dynamical effects of cosmic rays on the galactic magnetic field. Spontaneous current sheets and intrinsic rapid reconnection in interlaced magnetic field line topologies were the next big project, leading up to retirement. Finally, it is a pleasure to recall my many associates, whose fresh thinking helped stimulate the daily research activities.

关键词： dynamo -- magnetohydrodynamics -- plasma