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Deconvolving the pre-Himalayan Indian margin-Tales of crustal growth and destruction

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Geoscience Frontiers 2019年第3期10卷 863-872页

作者： Christopher j.Spencer brendan Dyck Catherine M.Mottram Nick M.W.Roberts Wei-Hua Yao Erin L.Martin Earth Dynamics Research Group The Institute for Geoscience Research (TIGeR) Department of Applied Geology Curtin University NERC Isotope Geosciences Laboratory British Geological Survey Department of Earth Sciences Simon Fraser University University Drive Department of Environment Earth and Ecosystems The Open UniversityWalton Hall Milton Keynes MK7 6AA UK School of Earth and Environmental Sciences University of Portsmouth Schoolof Earth Sciences and Engineering SunYat-sen University

The metamorphic core of the Himalaya is composed of Indian cratonic rocks with two distinct crustal affinities that are defined by radiogenic isotopic geochemistry and detrital zircon age spectra. One is derived predominantly from the Paleoproterozoic and Archean rocks of the Indian cratonic interior and is either represented as metamorphosed sedimentary rocks of the Lesser Himalayan Sequence(LHS) or as slices of the distal cratonic margin. The other is the Greater Himalayan Sequence(GHS) whose provenance is less clear and has an enigmatic affinity. Here we present new detrital zircon Hf analyses from LHS and GHS samples spanning over 1000 km along the orogen that respectively show a striking similarity in age spectra and Hf isotope ratios. Within the GHS, the zircon age populations at 2800-2500 Ma,1800 Ma, 1000 Ma and 500 Ma can be ascribed to various Gondwanan source regions; however, a pervasive and dominant Tonianage population(～860-800 Ma) with a variably enriched radiogenic Hf isotope signature(eHf = 10 to-20) has not been identified from Gondwana or peripheral accreted terranes. We suggest this detrital zircon age population was derived from a crustal province that was subsequently removed by tectonic erosion. Substantial geologic evidence exists from previous studies across the Himalaya supporting the Cambro-Ordovician Kurgiakh Orogeny. We propose the tectonic removal of Tonian lithosphere occurred prior to or during this Cambro-Ordovician episode of orogenesis in a similar scenario as is seen in the modern Andean and Indonesian orogenies, wherein tectonic processes have removed significant portions of the continental lithosphere in a relatively short amount of time. This model described herein of the pre-Himalayan northern margin of Greater India highlights the paucity of the geologic record associated with the growth of continental crust. Although the continental crust is the archive of Earth history, it is vital to recognize the ways in which preservation

关键词： Himalaya Gondwana Zircon Subduction erosion

Overhead shoulder press - In-front of the head or behind the head？

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journal of Sport and Health Science 2015年第3期4卷 250-257页

作者： Mark R. McKean brendan j. Burkett Faculty of Science Health and Education School of Health and Sport Sciences University of the Sunshine Coast Sippy Downs Queensland 4556 A ustralia

Background： Using a cross-sectional design comparison, two overhead press techniques （in-front of the head or behind the head） were compared. The purpose of this study was to determine the impact of behind the head or in-front of the head overhead pressing technique on shoulder range of movement （ROM） and spine posture. The overhead press is commonly prescribed exercise. The two techniques （in-front of the head or behind the head） may influence joint mechanics and therefore require an objective analysis. Methods： Passive shoulder ROM quantified using goniometric measures, dynamic ROM utilised three-dimensional （3D） biomechanical mea- sures （120 Hz） of 33 participants performing overhead pressing in a seated position. The timing and synchronisation of the upper limb shoulder and spine segments were quantified and influence of each technique was investigated. Results： The in-front technique commenced in lordotic position, whilst behind the head technique commenced in kyphotic position. Behind the head technique started with less thoracic extension than in-front condition. The thoracic spine remained extended and moved between 12~ and 15~ regardless of gender or technique. The techniques resulted in a significant difference between genders. Males were able to maintain a flat or normal lumbar lordosis, whereas females tended to kyphotic. Conclusion： Shoulder ROM was within passive ROM for all measures except external rotation for males with the behind the head technique. To avoid possible injury passive ROM should be increased prior to behind the head protocol. Females showed greater spine movements, suggesting trunk strengthening may assist overhead pressing techniques. For participants with normal trunk stability and ideal shoulder ROM, overhead pressing is a safe exercise （for the shoulder and spine） when performed either in-front of or behind the head.

关键词： 3RM Head ROM Shoulder flexibility Shoulder press Spine flexion

Investigation of coupled cobalt-silver nanoparticle system by plan view TEM

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Progress in Natural Science:Materials International 2012年第3期22卷 186-192页

作者： Daniel Fox Ruggero Verre brendan j. O'Dowd Sunil K. Arora Colm C. Faulkner Igor V. Shvets School of Physics and CRANN Trinity College Dublin CRANN Advanced Microscopy Laboratory Trinity College Dublin

We present a transmission electron microscopy (TEM) investigation of a coupled cobalt and silver nanoparticle system. A plan view in situ lift-out method for preparing samples for TEM using the focused ion beam (FIB) microscope was used. This technique is used to prepare high quality TEM samples with site specificity in a short time and with a high success rate. We demonstrate the ability of the plan view sample preparation technique to provide information about an ordered system of nanoparticles which could not be observed using standard FIB cross sectioning of the sample. High resolution TEM and energy dispersive X-ray spectroscopy mapping of both cross sectional and plan view samples are presented, clearly showing the significant benefit of plan view TEM analysis for certain samples.

关键词： Focused ion beam Transmission electron microscopy Lift-out Co Ag Nanoparticle

A brief history of the Rheic Ocean

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Geoscience Frontiers 2012年第2期3卷 125-135页

作者： R.Damian Nance Gabriel Gutirrez-Alonso j.Duncan Keppie Ulf Linnemann j.brendan Murphy Cecilio Quesada Rob A.Strachan Nigel H.Woodcock Department of Geological Sciences 316 Clippinger Laboratories Ohio University Departamento de Geología Universidad de Salamanca 33708 Salamanca Departamento de Geología Regional Instituto de Geología Universidad Nacional Autónoma de Mxico Senckenberg Naturhistorische Sammlungen Dresden Museum fur Mineralogie und Geologie Konigsbrucker Landstra βe 159D-01109 DresdenGermany Department of Earth Sciences St.Francis Xavier University Instituto Geolóogico y Minero de Espaa Ríos Rosas 2328003 MadridSpain School of Earth & Environmental Sciences University of Portsmouth Department of Earth Sciences University of Cambridge Downing StreetCambridge CB2 3EQUK

The Rheic Ocean was one of the most important oceans of the Paleozoic Era. It lay between Laurentia and Gondwana from the Early Ordovician and closed to produce the vast Ouachita- Alleghanian-Variscan orogen during the assembly of Pangea. Rifting began in the Cambrian as a continua- tion of Neoproterozoic orogenic activity and the ocean opened in the Early Ordovician with the separation of several Neoproterozoic arc terranes from the continental margin of northern Gondwana along the line of a former suture. The rapid rate of ocean opening suggests it was driven by slab pull in the outboard Iapetus Ocean. The ocean reached its greatest width with the closure of Iapetus and the accretion of the peri- Gondwanan arc terranes to Laurentia in the Silurian. Ocean closure began in the Devonian and continued through the Mississippian as Gondwana sutured to Laurussia to form Pangea. The ocean consequently plays a dominant role in the Appalachian-Ouachita orogeny of North America, in the basement geology of southern Europe, and in the Paleozoic sedimentary, structural and tectonothermal record from Middle America to the Middle East. Its closure brought the Paleozoic Era to an end.

关键词： Rheic Ocean Variscan-Alleghanian-Ouachita orogen Pangea North America Europe

The influence of chemical composition on models of Type Ia supernovae

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Frontiers of physics 2013年第2期8卷 168-188页

作者： Alan C. Calder brendan K. Krueger Aaron P. jackson Dean M. Townsley Department of Physics Astronomy The State University of New York - Stony Brook Stony BrookUSA NY 11794 New York Center for Computational Sciences The State University of New York - Stony Brook Stony BrookUSA NY 11794 National Research Council Research Associateship Program and Laboratories for Computational Physics and Fluid Dynamics Naval Research Laboratory WashingtonUSA DC 20375 Department of Physics and Astronomy The University of Alabama TuscaloosaUSA AL 35487

Type Ia supernovae are bright stellar explosions distinguished by standardizable light curves that allow for their use as distance indicators for cosmological studies. Despite the highly successful use of these events in this capacity, many fundamental questions remain. Contemporary research inves- tigates how properties of the progenitor system that follow from the host galaxy such as composition and age influence the brightness of an event with the goal of better understanding and assessing the intrinsic scatter in the brightness. We provide an overview of these supernovae and proposed progenitor systems, all of which involve one or more compact stars known as white dwarfs. We describe contemporary research investigating how the composition and structure of the progenitor white dwarf systematically influences the explosion outcome assuming the progenitor is a single white dwarf that has gained mass from a companion. We present results illustrating some of these systematic effects from our research.

关键词： hydrodynamics nuclear reactions nucleosynthesis abundances stars: supernovae:general stars: white dwarfs

Exploring the percentage of COVID-19 cases reported in the community in Canada and associated case fatality ratios

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Infectious Disease Modelling 2021年第1期6卷 123-132页

作者： brendan P.Dougherty Ben A.Smith Carolee A.Carson Nicholas H.Ogden Centre for Food-borne and Environmental Zoonotic Infectious Diseases Public Health Agency of Canada370 Speedvale Ave W.GuelphONN1H 7M7Canada Public Health Risk Sciences Division National Microbiology LaboratoryPublic Health Agency of Canada370 Speedvale Ave W.GuelphONN1H 7M7Canada Public Health Risk Sciences Division National Microbiology LaboratoryPublic Health Agency of CanadaSt.HyacintheQCJ2S 2M2Canada

While surveillance can identify changes in COVID-19 transmission patterns over time and space,sections of the population at risk,and the efficacy of public health measures,reported cases of COVID-19 are generally understood to only capture a subset of the actual number of *** primary objective was to estimate the percentage of cases reported in the general community,considered as those that occurred outside of long-term care facilities(LTCFs),in specific provinces and Canada as a *** applied a methodology using the delay-adjusted case fatality ratio(CFR)to all cases and deaths,as well as those representing the general *** second objective was to assess whether the assumed CFR(mean=1.38%)was appropriate for calculating underestimation of cases in *** were developed for the period from March 11th,2020 to September 16th,*** of the percentage of cases reported(PrCR)and CFR varied spatially and temporally across *** the majority of provinces,and for Canada as a whole,the PrCR increased through the early stages of the *** estimated PrCR in general community settings for all of Canada increased from 18.1%to 69.0%throughout the entire study *** were greater when considering only those data from outside of *** estimated upper bound CFR in general community settings for all of Canada decreased from 9.07%on March 11th,2020 to 2.00%on September 16th,***,the true CFR in the general community in Canada was likely less than 2%on September *** to our analysis,some provinces,such as Alberta,Manitoba,Newfoundland and Labrador,Nova Scotia,and Saskatchewan reported a greater percentage of cases as of September 16th,compared to British Columbia,Ontario,and *** could be due to differences in testing rates and criteria,demographics,socioeconomic factors,race,and access to healthcare among the *** investigation into these factors could reveal differences among provinc

关键词： SARS-CoV-2 Underestimation Coronavirus disease Long term care facilities Case fatality ratio

An Alzheimer's Disease-Relevant Presenilin-1 Mutation Augments Amyloid-Beta-Induced Oligodendrocyte Dysfunction

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神经损伤与功能重建 2011年第2期6卷 128-141页

作者： MAYA K.DESAI brendan j.GUERCIO WADE C.NARROW WILLIAM j.BOWERS Department of Pharmacology and Physiology University of Rochester School of Medicine and DentistryRochesterNew York Center for Neural Development and Disease University of Rochester School of Medicine and DentistryRochesterNew York Department of Microbiology and Immunology University of Rochester School of Medicine and DentistryRochesterNew York Department of Neurology University of Rochester School of Medicine and DentistryRochesterNew York

研究表明,家族性阿尔茨海默病(FAD)患者处于无症状或临床前阶段时,脑白质即出现病理改变。此种改变在髓鞘破坏及阿尔茨海默病(AD)病理生理中的作用有待进一步研究阐明。笔者前期研究证实,三重转基因AD小鼠(人淀粉前体蛋白基因的Swedish... 详细信息

研究表明,家族性阿尔茨海默病(FAD)患者处于无症状或临床前阶段时,脑白质即出现病理改变。此种改变在髓鞘破坏及阿尔茨海默病(AD)病理生理中的作用有待进一步研究阐明。笔者前期研究证实,三重转基因AD小鼠(人淀粉前体蛋白基因的Swedish突变,早老素-1 M146V(PS1M146V)敲入突变及tauP301L突变)表现出类似FAD患者的髓鞘破坏,Aβ1-42促进了白质病变。本研究离体实验证实,PS1M146V变异导致小鼠少突胶质前体细胞在分化过程中易出现类似Aβ1-42诱导的变化。PS1M146V的表达损伤少突胶质前体细胞的功能并影响髓鞘碱性蛋白的分布,暴露于Aβ1-42加重此影响。由PS1M146V及Aβ1-42导致的髓鞘破坏及髓鞘碱性蛋白在亚细胞结构中的误定位可被TWS119(糖原合成激酶(GSK)-3β抑制剂)抑制,提示GSK-3β激酶活动在此病理过程中有重要作用。综上所述,本研究有助于增加对AD早期无症状阶段,由PS1M146V及Aβ1-42导致少突胶质细胞功能异常及髓鞘损伤的机制的理解,并提供了针对少突胶质细胞预防AD相关白质病变的新的治疗靶点。

关键词：阿尔茨海默病白质髓磷脂少突胶质细胞髓鞘碱性蛋白淀粉β样蛋白早老素-1 3重转基因AD

Rapid,high-resolution detection of environmental change over continental scales from satellite data–the Earth Observation Data Cube

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International journal of Digital Earth 2016年第1期9卷 106-111页

作者： Adam Lewis Leo Lymburner Matthew B.j.Purss brendan Brooke Ben Evans Alex Ip Arnold G.Dekker james R.Irons Stuart Minchin Norman Mueller Simon Oliver Dale Roberts Barbara Ryan Medhavy Thankappan Rob Woodcock Lesley Wyborn Geoscience Australia CanberraAustralia National Computational Infrastructure Australian National UniversityCanberraAustralia Commonwealth Scientific and Industrial Research Organisation CanberraAustralia NASA Goddard Space Flight Center GreenbeltMDUSA Research School of Finance Actuarial Studies and Applied StatisticsANUCanberraAustralia The Group on Earth Observations Secretariate GenevaSwitzerland

The effort and cost required to convert satellite Earth Observation(EO)data into meaningful geophysical variables has prevented the systematic analysis of all available *** overcome these problems,we utilise an integrated High Performance Computing and Data environment to rapidly process,restructure and analyse the Australian Landsat data *** this approach,the EO data are assigned to a common grid framework that spans the full geospatial and temporal extent of the observations–the EO Data *** approach is pixel-based and incorporates geometric and spectral calibration and quality assurance of each Earth surface reflectance *** demonstrate the utility of the approach with rapid time-series mapping of surface water across the entire Australian continent using 27 years of continuous,25 m resolution *** preliminary analysis of the Landsat archive shows how the EO Data Cube can effectively liberate high-resolution EO data from their complex sensor-specific data structures and revolutionise our ability to measure environmental change.

关键词： Earth Observation Data Cube HPD HPC surface water Landsat Australia

Development of a Novel Hybrid Aluminum-Based Sol-Gel Materials: Application to the Protection of AA2024-T3 Alloys in Alkaline Environment

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Advances in Materials Physics and Chemistry 2014年第5期4卷 75-84页

作者： Mohamed Oubaha Padinchare Covilakath Rajath Varma brendan Duffy Zuhair Mattoug Gasem Steven j. Hinder Centre for Research Excellence in Corrosion King Fahd University of Petroleum and Minerals Dhahran KSA Centre for Research in Engineering Surface Technology (CREST) FOCAS Institute Dublin Institute of Technology Dublin Ireland The Surface Analysis Laboratory Faculty of Engineering and Physical Sciences University of SurreyGuildford UK

Extensive research on environmentally complaint sol-gel coatings is currently underway for a wide range of applications. Sol-gel technology combines the synergistic properties of inorganic and organic components to design nanostructured coating materials with advanced physical properties. Through a judicious choice of precursors and additives improved performances, such as chemical resistance or pH stability, it can be achieved. This is of particular interest for copper rich AA 2024-T3 aluminium alloys used on aircraft, where increase in local pH occurs at corrosion sites. This work focuses on improving the alkaline stability and anticorrosion properties of such a sol-gel coatings on AA2024-T3 by incorporating aluminium functionality into hybrid materials prepared from hydrolysis and condensation of 3-methacryloxypropyltrimethoxysilane, zirconium n-propoxide and zirconium/alkoxide precursors. Dynamic light scattering technique was used to study the particle size nature of the sol-gel materials in colloidal form. X-ray photoelectron spectroscopy was used to study the oxidation state of the aluminium and zirconium at the sol-gel coating surface. Field emission scanning electrochemical microscopy coupled with energy dispersive spectroscopy was used to assess the microstructural features. Electrochemical characterisations employing potentiodynamic scanning and electrochemical impedance spectroscopy were performed to investigate the anticorrosion performance of the hybrid sol-gel coatings. The best anti-corrosive protection of AA2024-T3 in an alkaline saline solution (pH = 10) was achieved with materials containing 10 mol% and 15 mol% aluminium doped sol-gel coatings. This study shows that presence of aluminium has a positive effect on alkaline stability of the coatings and is a potential green candidate for the protective coatings on aerospace alloys.

关键词： Sol-Gel Aluminium Zirconium Corrosion Coatings Hybrid: Organo-Silane