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Chinese Journal of Polymer Science 2008年第3期26卷 263-273页

作者：杨继萍 Philip J.brown School of Material Science and Engineering Beihang UniversityBeijing 100083China School of Materials Science and Engineering Clemson UniversitySC29634USA

Membranes for gas separation have developed significantly in the last twenty years,however,there is still a need for high temperature and chemically resistant membranes that exhibit good selectivity and gas *** study examines the fundamental properties of polyetherketone (PEK,a thermally stable and chemically resistant polymer) membranes prepared using concentrated sulphuric acid (98% H_2SO_4) as the ***-solvents used in the work included acetic acid,ethanol,methanol,glycerol,and water....

关键词： Polyetherketones Membranes Gas permeation Internal coagulant effect Morphology

From cortex to cord: motor circuit plasticity after spinal cord injury

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Neural Regeneration Research 2019年第12期14卷 2054-2062页

作者： Andrew R. brown Marina Martinez Département de Neurosciences Facultéde MédecineUniversitéde MontréalQuébecCanada H?pital du Sacré-Coeur de Montréal(CIUSS-NIM) MontréalQuébecCanada Groupe de Recherche sur le Système Nerveux Central Universitéde MontréalMontréalQuébecCanada

Spinal cord injury is associated with chronic sensorimotor deficits due to the interruption of ascending and descending tracts between the brain and spinal cord. Functional recovery after anatomically complete spinal cord injury is limited due to the lack of long-distance axonal regeneration of severed fibers in the adult central nervous system. Most spinal cord injuries in humans, however, are anatomically incomplete. Although restorative treatment options for spinal cord injury remain currently limited, research from experimental models of spinal cord injury have revealed a tremendous capability for both spontaneous and treatment-induced plasticity of the corticospinal system that supports functional recovery. We review recent advances in the understanding of corticospinal circuit plasticity after spinal cord injury and concentrate mainly on the hindlimb motor cortex, its corticospinal projections, and the role of spinal mechanisms that support locomotor recovery. First, we discuss plasticity that occurs at the level of motor cortex and the reorganization of cortical movement representations. Next, we explore downstream plasticity in corticospinal projections. We then review the role of spinal mechanisms in locomotor recovery. We conclude with a perspective on harnessing neuroplasticity with therapeutic interventions to promote functional recovery.

关键词： spinal cord injury motor cortex motor map corticospinal tract neuroplasticity functionalrecovery animal models forelimb hindlimb locomotion

The Pleiomorphic Plant MTOC:An Evolutionary Perspective

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Journal of Integrative Plant Biology 2007年第8期49卷 1142-1153页

作者： RoyC.brown BettyE.Lemmon Department of Biology University of Louisiana-LafayetteLafayetteLA 70504USA

γ-Tubulin is an essential component of the microtubule organizing center （MTOC） responsible for nucleating microtubules in both plants and animals. Whereas γ-tubulin is tightly associated with centrosomes that are inheritable organelles in cells of animals and most algae, it appears at different times and places to organize the myriad specialized microtubule systems that characterize plant cells. We have traced the distribution of γ-tubulin through the cell cycle in representative land plants （embryophytes） and herein present data that have led to a concept of the pleiomorphic and migratory MTOC. The many forms of the plant MTOC at spindle organization constitute pleiomorphism, and stage-specific “migration” is suggested by the consistent pattern of redistribution of γ-tubulin during mitosis. Mitotic spindles may be organized at centriolar centrosomes （only in final divisions of spermatogenesis）, polar organizers （POs）, plastid MTOCs, or nuclear envelope MTOCs （NE-MTOCs）. In all cases, with the possible exception of centrosomes in spermatogenesis, the γ-tubulin migrates to broad polar regions and along the spindle fibers, even when it is initially a discrete polar entity. At anaphase it moves poleward, and subsequently migrates from polar regions （distal nuclear surfaces） into the interzone （proximal nuclear surfaces） where interzonal microtubule arrays and phragmoplasts are organized. Following cytokinesis, γ-tubulin becomes associated with nuclear envelopes and organizes radial microtubule systems （RMSs）. These may exist only briefly, before establishment of hoop-like cortical arrays in vegetative tissues, or they may be characteristic of interphase in syncytial systems where they serve to organize the common cytoplasm into nuclear cytoplasmic domains （NCDs）.

关键词： angiosperms bryophytes cell cycle life cycle microtubule mitosis γ-tubulin.

Spatial context in the calculation of gas emissions for underground coal mines

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International Journal of Mining Science and Technology 2017年第5期27卷 787-794页

作者： Patrick Booth Heidi brown Jan Nemcik Ren Ting School of Civil Mining and Environmental EngineeringSchool of Earth and Environmental SciencesUniversity of WollongongWollongong 2500Australia

The prediction of gas emissions arising from underground coal mining has been the subject of extensive research for several decades, however calculation techniques remain empirically based and are hence limited to the origin of calculation in both application and resolution. Quantification and management of risk associated with sudden gas release during mining(outbursts) and accumulation of noxious or combustible gases within the mining environment is reliant on such predictions, and unexplained variation correctly requires conservative management practices in response to risk. Over 2500 gas core samples from two southern Sydney basin mines producing metallurgical coal from the Bulli seam have been analysed in various geospatial context including relationships to hydrological features and geological structures. The results suggest variability and limitations associated with the present traditional approaches to gas emission prediction and design of gas management practices may be addressed using predictions derived from improved spatial datasets, and analysis techniques incorporating fundamental physical and energy related principles.

关键词： Gas emission prediction Spatial analysis Underground coal mining Risk management Greenhouse gas Climate

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Editorial

Journal of Rock Mechanics and Geotechnical Engineering 2017年第2期9卷 195-196页

作者： E.T. brown Golder Associates Pty. Ltd. P.O. Box 1734 Milton QLD 4064 Australia

The Aims and Scope of the Journal of Rock Mechanics and Geotechnical Engineering(JRMGE)indicate that it"is concerned with the latest research achievements in rock mechanics and geotechnical engineering The topics covered by the JRMGE include new theories,new technologies,new methods and experiences,in-situ and laboratory tests,new developments,case studies and timely reviews on selected subjects in rock mechanics and geotechnical engineering."

关键词： AIMS SCOPE MECHANICS

Genre Fiction; Science Fiction; The Quest for Utopia

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外国文学研究 2005年第6期27卷 36-40页

作者： Charles N. brown founder and editor-in-chief of Locus Publications USA 23-time Hugo winner

This paper will discuss the difference between genre fiction and mainstream fiction, the difference between science fiction and other fields of genre fiction, and in particular, the philosophical use of science fiction in our search for a better world. All genres used to be called ″romance″ to distinguish them from ″true″ novels. There were arguments about it in Hawthorne’s The House of Seven Gables and in a heated exchange between H.G. Wells and Henry James. I will talk about this difference. All genre fiction pays attention to the external world, but science fiction is the only one of them that looks forward by being grounded in the present. Is science fiction really a genre? There are some doubts. Science fiction is not about science per se, but about the philosophy of science:the study of the external world and its relation to man. It is ideal for ″thought experiments.″ By exploring possible futures, we cannot only examine our present world, but can see ways in which it can be improved. Hence, science fiction is the search for, if not utopia, then at least a better world. This paper will also discuss the ideas of Kim Stanley Robinson, Ursula K. Le Guin, and others in their search for a better future.

关键词：美国文学研究虚构小说科学小说

Back Analysis in Rock Engineering

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第3期10卷 611-612页

作者： E.T.brown Golder Associates Pty Ltd

This volume is the fourth in the International Society for Rock Mechanics and Rock Engineering(ISRM)Book Series,edited by Professor Xia-Ting Feng,ISRM Past-President and Vice Editor-in-Chief of this *** author,Professor Shunsuke Sakurai,of Kobe University,Japan,has also had a long and distinguished association with the ISRM,having served as the Society’s ninth President in the

关键词： In Back Analysis in Rock Engineering

A novel role for tissue-nonspecific alkaline phosphatase at the blood-brain barrier during sepsis

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Neural Regeneration Research 2021年第1期16卷 99-100页

作者： Divine C.Nwafor Candice M.brown Department of Neuroscience West Virginia University Health Science CenterMorgantownWVUSA Department of Microbiology Immunologyand Cell BiologySchool of MedicineWest Virginia University Health Science CenterMorgantownWVUSA

Sepsis and the blood-brain barrier(BBB):Sepsis is a life threatening systemic inflammatory condition involving multi-organ *** World Health Organization estimates that about 30 million people are affected by sepsis every year,and at least 6 million people die from sepsis each *** of approximately 24 million sepsis survivors,it is estimated that 70%of these individuals will experience some form of long-term neurological impairment(Iwashyna et al.,2010).Thus,when combined with prevention,diagnosis,and therapeutic management strategies,a functional understanding of the mechanisms that promote sepsis-associated neurological impairment is necessary to address the clinical challenges and economic burdens faced when treating sepsis.

关键词： prevention diagnosis barrier

Counting rational points on cubic curves

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Science China Mathematics 2010年第9期53卷 2259-2268页

作者： HEATH-brown Roger TESTA Damiano Mathematical Institute University of OxfordOxfordUK

We prove upper bounds for the number of rational points on non-singular cubic curves defined over the *** bounds are uniform in the curve and involve the rank of the corresponding *** method used in the proof is a com... 详细信息

关键词： cubic curves rational points counting function elliptic curves determinant method m-descent

EMERGENT PERMITTING STRATEGIES FOR NATURAL BUILDING SYSTEMS IN ONTARIO

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Journal of Green Building 2011年第4期6卷 17-25页

作者： Craig brown Environmental Applied Science and Management Ryerson University

INTRODUCTION Lowering the carbon intensity of the built environment is one of many tasks that must be undertaken in order to address climate change and to encourage *** siting,design,construction,occupancy,renovation,and disposal of single-family homes are all factors that contribute to the large carbon emissions generated by the *** are numerous strategies that seek to minimize the amount of emissions generated by a house during its *** paper explores the use of so-called natural building systems in building envelope construction.

关键词： Ontario Building Code alternative solutions natural building systems home construction permit