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Origins of the supercontinent cycle

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Geoscience Frontiers 2013年第4期4卷 439-448页

作者： R.Damian Nance J.Brendan murphy Department of Geological Sciences.316 Clippinger Laboratories.Ohio University.Athens.OH 45701.USA Department of Earth Sciences st.Francis Xavier UniversityAntigonishNova Scotia B2G 2W5.Canada

The supercontinent cycle, by which Earth history is seen as having been punctuated by the episodic assembly and breakup of supercontinents, has influenced the rock record more than any other geologic phenomena, and its recognition is arguably the most important advance in Earth Science since plate tectonics. It documents fundamental aspects of the planet＇s interior dynamics and has charted the course of Earth＇s tectonic, climatic and biogeochemical evolution for billions of years. But while the widespread realization of the importance of supercontinents in Earth history is a relatively recent development, the supercontinent cycle was first proposed thirty years ago and episodicity in tectonic processes was recognized long before plate tectonics provided a potential explanation for its occurrence. With interest in the supercontinent cycle gaining momentum and the literature expanding rapidly, it is instructive to recall the historical context from which the concept developed. Here we examine the supercontinent cycle from this perspective by tracing its development from the early recognition of long-term epi- sodicity in tectonic processes, through the identification of tectonic cycles following the advent of plate tectonics, to the first realization that these phenomena were the manifestation of episodic superconti- nent assembly and breakup.

关键词： Supercontinent cyclePlate tectonicsTectonic episodicitySecular trends

Speculations on the mechanisms for the formation and breakup of supercontinents

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Geoscience Frontiers 2013年第2期4卷 185-194页

作者： J.Brendan murphy R.Damian Nance Department of Earth Sciences.St.Francis Xavier University Antigonish.Nova Scotia B2G 2W5Canada Department of Geological Sciences Ohio UniversityAthensOH 45701USA

The supercontinent cycle has had a profound effect on the Earth＇s evolution since the Late Archean but our understanding of the forces responsible for its operation remains *** appear to form by two end-member processes：extroversion,in which the oceanic lithosphere surrounding the supercontinent（exterior ocean） is preferentially subducted（***）,and introversion in which the oceanic lithosphere formed between dispersing fragments of the previous supercontinent（interior ocean） is preferentially subducted（***）.Extroversion can be explained by ＂top-down＂ geodynamics, in which a supercontinent breaks up over a geoid high and amalgamates above a geoid low. Introversion,on the other hand,requires that the combined forces of slab-pull and ridge push（which operate in concert after supercontinent break-up） must be overcome in order to enable the previously dispersing continents to turn *** may begin when subduction zones are initiated along boundaries between the interior and exterior oceans and become trapped within the interior *** speculate that the reversal in continental motion required for introversion may be induced by slab avalanche events that trigger the rise of superplumes from the core-mantle boundary.

关键词： Supercontinent cycle Introversion Extroversion Pangea Rodinia Pannotia

A near infrared spectroscopy calibration for the prediction of fresh grass quality on Irish pastures

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Information Processing in Agriculture 2022年第2期9卷 243-253页

作者： Darren J.murphy Bernadette O’Brien Michael O’Donovan Tomas Condon Michael D.murphy Teagasc Animal&Grassland Research and Innovation CentreMooreparkFermoyCo.CorkIreland Department of Process Energy and Transport EngineeringMunster Technological UniversityCorkIreland

The aim of this study was to develop near infrared spectroscopy(NIRS)calibrations to predict quality parameters,dry matter(DM,g kg1)and crude protein(CP,g kg1 DM),in fresh un-dried *** of these parameters would enable more precise allocation of quality herbage to grazing *** ryegrass samples(n=1615)were collected over the 2017 and 2018 grazing seasons at Teagasc Moorepark to develop a NIRS calibration *** samples were collected for an independent validation dataset(n=197)during the 2019 grazing *** were scanned using a FOSS 6500 spectrometer at 2 nm intervals in the range of 1100~2500 nm and absorption was recorded as log 1/Reflec*** wet chemistry analysis was carried out for both parameters and the resultant data were calibrated against spectral data by means of modified partial least squares regression.A range of mathematical spectral treatments were examined for each calibration,which were ranked in order of standard error of prediction(SEP)and ratio of percent deviation(RPD).Best performing calibrations achieved high predictive precision for DM(R2=0.86 SEP=9.46 g kg1,RPD=2.60)and moderate precision for CP(R2=0.84 SEP=20.38 g kg1 DM,RPD=2.37).These calibrations will aid the optimisation of grassland management and the development of precision agricultural technologies.

关键词： Near infrared spectroscopy Fresh grass analysis Grassland management Grass quality Precision agriculture

BUCKLING LOADS AND EIGENFREQUENCIES OF A BRACED BEAM RESTING ON AN ELASTIC FOUNDATION

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Acta Mechanica Solida Sinica 2011年第6期24卷 510-518页

作者： Yin Zhang Yun Liu Peng Chen Kevin D murphy State Key Laboratory of-Nonlinear Mechanics （LN M） Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China Faculty of Information and Automation Kunming University of Science and Technology Kunming 650051 China Department of Civil Engineerning Guangdong Technical College of Water Resources and Electric Engineering Guangzhou 510635 China Department of Mechanical Engineering University of Connecticut Storrs CT 06269 USA

The eigenvalue problems of the buckling loads and natural frequencies of a braced beam on an elastic foundation are investigated. sented. The eigenvalues vary with the different The exact solutions for the eigenvalues are preparameters and are especially sensitive to the brace location. As the beam of a continuous system has infinite eigenvalues and these eigenvalues are influenced differently by a brace, the eigenvalues show rich variation patterns. Because these eigenvalues physically correspond to the structure buckling loads and natural frequencies, the study on the eigenvalues variation patterns can offer a design guidance of using a lateral brace of translation spring to strengthen the structure.

关键词： beam elastic foundation buckling eigenfrequency curve crossing curve veering

Natural Killer Cells:Biology and Clinical Use in Cancer Therapy

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Cellular & Molecular Immunology 2004年第1期1卷 12-21页

作者： William H.D.Hallett William J.murphy Department of Microbiology and Immunology University of Nevada School of Medicine.University of Nevada.Reno.Reno.NV.USA.

Natural killer (NK) cells have the ability to mediate both bone marrow rejection and promote engraftment,as well as the ability to elicit potent anti-tumor *** the clinical results for these processes are still *** understanding of NK cell biology,from activating and inhibitory receptor functions to the role of NK cells in allogeneic transplantation,needs to be appreciated in order to draw out the clinical potential of NK *** of bone marrow cell (BMC) rejection are known to be dependant on inhibitory receptors specific for major histocompatibility complex (MHC) molecules and on activating receptors that have many potential *** modulation of activating and inhibitory receptors may hold the key to clinical success involving NK ***-clinical studies in mice have shown that different combinations of activating and inhibitory receptors on NK cells can reduce graft-versus-host disease (GVHD),promote engraftment,and provide superior graft-versus-tumor (GVT) *** clinical data have shown that the use of KIR-ligand incompatibility produces tremendous graft-versus-leukemia effect in patients with acute myeloid leukemia at high risk of *** review will attempt to be a synthesis of current knowledge concerning NK cells,their involvement in BMT,and their use as an immunotherapy for cancer and other hematologic *** & Molecular Immunology.2004;1(1):12-21.

关键词： NK cell BMT GVHD GVT

The role of organic electron donors in the initiation of BHAS base-induced coupling reactions between haloarenes and arenes

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Science China Chemistry 2019年第11期62卷 1425-1438页

作者： Andrew J.Smith Darren L.Poole John A.murphy Department of Pure and Applied Chemistry University of StrathclydeStrathclydeGlasgow G11XLUnited Kingdom Flexible Discovery Unit GlaxoSmithKline Medicines Research CentreStevenageSG12NYUnited Kingdom

Coupling reactions between haloarenes and arenes(including heteroarenes)that are conducted without added transition metals but in the presence of KOtBu or NaOtBu,have been a topic of great interest since their discovery in *** organic structures act as additives that assist these *** additives are converted into organic electron donors by the butoxide base and this leads to initiation of the coupling reactions,which proceed by radical chain *** review provides an overview of the initiation stages of these reactions.

关键词： organic electron donor potassium tert-butoxide electron transfer base-promoted homolytic aromatic substitution(BHAS) coupling benzyne

Trans-synaptic degeneration as a mechanism of neurodegeneration in multiple sclerosis

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Neural Regeneration Research 2023年第12期18卷 2682-2684页

作者： Olwen C.murphy Peter A.Calabresi Shiv Saidha Division of Neuroimmunology and Neurological Infections Department of NeurologyJohns Hopkins UniversityBaltimoreMDUSA

Multiple sclerosis(MS) is regarded as an immunemediated,demyelinating disorder of the central nervous system,however neuroaxonal degeneration is accepted as the principal substrate of disability accumulation(Dutta and... 详细信息

关键词： degeneration sclerosis myelin

Fabrication of three-dimensional islet models by geometry-controlled hanging drop method

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Acta Mechanica Sinica 2019年第2期35卷 329-337页

作者： Bin Gao Ce Jing Kelvin Ng Belinda Pingguan-murphy Qingzhen Yang Department of Endocrinology and Metabolism The First Affiliated Hospital Air Force Military Medical University Xi’an 710032 China Outpatient Department of Lanzhou Military Region 940 Hospital Joint Logistics Support Force of the People's Liberation Army of China Lanzhou 730000 China Department of Biomedical Engineering Faculty of Engineering University of Malaya Kuala Lumpur 50603 Malaysia Key Laboratory of Biomedical Information Engineering of Ministry of Education School of Life Science and Technology Xi'an Jiaotong University Xi'an 710049 China Bioinspired Engineering and Biomechanics Center (BEBC) Xi’an Jiaotong University Xi’an 710049 China

Hanging-drop method has been widely used to fabricate three-dimensional (3D) in vitro tissue models due to its advantages such as being easy to perform, inexpensive, and permitting precise control of cell spheroid formation. The geometry of hanging drop may play a critical role on the formation of cell spheroids, which, however, has not been explored. In this study, we developed a modified hanging-drop platform that enables the production of cell spheroids in a high-throughput manner by controlling hanging drop geometry with defined spreading ring. The surface tension force is proportional to the spreading ring and gravitational force is determined by the droplet volume, and the geometry can be determined by the balance between surface tension and gravity.β-TC-6 cell spheroids with optimized diameters were fabricated as 3D in vitro islet models. The models show morphology similar to primary islets and have functionality that more closely resembles primary islets than two-dimensional cell culture. The developed platform holds great potential for engineering well-controlled in vitro tissue models for various applications such as physiological and pathological studies, drug screening, as well as transplantation for treatment purpose.

关键词： Hanging drop cell culture Mechanical microenvironment Drop geometry 3D islet spheroids

Cyclin-dependent kinase inhibitors in brain cancer:current state and future directions

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Cancer Drug Resistance 2020年第1期3卷 48-62页

作者： Viktorija Juric Brona murphy Department of Physiology and Medical Physics Royal College of Surgeons in IrelandDublin D02Ireland

Cyclin-dependent kinases(CDKs)are important regulatory enzymes in the normal physiological processes that drive cell-cycle transitions and regulate *** all cancers harbour genomic alterations that lead to the constitutive activation of CDKs,resulting in the proliferation of cancer *** inhibitors(CKIs)are currently in clinical use for the treatment of breast cancer,combined with endocrine *** this review,we describe the potential of CKIs for the treatment of cancer with specific focus on glioblastoma(GBM),the most common and aggressive primary brain tumour in *** intense effort to combat GBM with surgery,radiation and temozolomide chemotherapy,the median survival for patients is 15 months and the majority of patients experience disease recurrence within 6-8 months of treatment *** therapeutic approaches are urgently needed for both newly diagnosed and recurrent GBM *** this review,we summarise the current preclinical and clinical findings emphasising that CKIs could represent an exciting novel approach for GBM treatment.

关键词： Cyclin-dependent kinases cyclin-dependent kinase inhibitors gliomas glioblastoma clinical trials resistance