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Polyethylene glycol fusion repair of severed rat sciatic nerves reestablishes axonal continuity and reorganizes sensory terminal fields in the spinal cord

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Neural regeneration research 2025年第7期20卷 2095-2107页

作者： Emily A.Hibbard Liwen Zhou Cathy Z.Yang Karthik Venkudusamy Yessenia Montoya Alexa Olivarez George D.bittner Dale r.Sengelaub Program in Neuroscience Indiana UniversityBloomingtonINUSA Department of Neuroscience University of Texas at AustinAustinTXUSA

Peripheral nerve injuries result in the rapid degeneration of distal nerve segments and immediate loss of motor and sensory functions;behavioral recovery is typically *** used a plasmalemmal fusogen,polyethylene glycol(PEG),to immediately fuse closely apposed open ends of severed proximal and distal axons in rat sciatic *** have previously reported that sciatic nerve axons repaired by PEG-fusion do not undergo Wallerian degeneration,and PEG-fused animals exhibit rapid(within 2–6 weeks)and extensive locomotor ***,our previous report showed that PEG-fusion of severed sciatic motor axons was non-specific,i.e.,spinal motoneurons in PEG-fused animals were found to project to appropriate as well as inappropriate target *** this study,we examined the consequences of PEG-fusion for sensory axons of the sciatic *** adult male and female rats(Sprague–Dawley)received either a unilateral single cut or ablation injury to the sciatic nerve and subsequent repair with or without(Negative Control)the application of *** action potentials recorded immediately after PEG-fusion repair confirmed conduction across the injury *** success of PEG-fusion was confirmed through Sciatic Functional Index testing with PEG-fused animals showing improvement in locomotor function beginning at 35 days *** 2–42 days postoperatively,we anterogradely labeled sensory afferents from the dorsal aspect of the hindpaw following bilateral intradermal injection of wheat germ agglutinin conjugated horseradish ***-fusion repair reestablished axonal *** to unoperated animals,labeled sensory afferents ipsilateral to the injury in PEG-fused animals were found in the appropriate area of the dorsal horn,as well as inappropriate mediolateral and rostrocaudal ***,despite having intact peripheral nerves,similar reorganizations of labeled sensory afferents were also observed contralateral to the injury and repa

关键词： axotomy dorsal horn peripheral nerve injury plasticity polyethylene glycol(PEG) sciatic nerve sensory terminals wheat germ agglutinin horseradish peroxidase

Injection of N-radicals into Diesel Engine Exhaust Treated by Plasma for Improved NO_x removal: A Feasibility Study

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Plasma Science and Technology 2006年第2期8卷 202-206页

作者： b. S. rAJANIKANTH b. r. SUSHMA Dept. of High Voltage Engineering Indian Institute of Science Bangalore 560012 India

reported in this paper is a feasibility study on the injection of plasma induced N radicals for the abatement of NO and NOx present in the actual diesel exhaust. The radical laden diesel exhaust was further treated by discharge plasma in a dielectric barrier discharge reactor. N radicals were produced in a separate plasma reactor filled with baTiO3 pellets and were then injected into the treatment zone, There was a significant improvement in the efficiency when the radicals were injected compared to that when there was no radical injection. The efficiency of NOx removal at 0 load with plasma alone was 14% whereas with the injection of N radicals it went up to 38%, The results of the experiments conducted at different loads are discussed,

关键词： N-radical diesel engine exhaust NOx removal plasma treatment

Determinants of the Specif icity of Protein Targeting to Chloroplasts or Mitochondria

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Molecular Plant 2019年第7期12卷 893-895页

作者： lucas McKinnon Steven M.Theg Department of Plant biology University of California Davis Davis CA USA

Chloroplasts and mitochondria are both thought to have arisen through primary endosymbiosis (Kutschera and Niklas, 2005). As each organelle evolved, most of its genome was transferred to the host nucleus resulting in the vast majority of its proteome being nuclear encoded and synthesized on cytosolic ribosomes (Shi and Theg, 2013).

关键词： Chloroplasts Mitochondria

Nitrogen in Chinese coals

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Chinese Journal Of Geochemistry 2011年第2期30卷 248-254页

作者： Finkelman r.b. U.S.Geological Survey Mail Stop 956VA 20192USA

Three hundred and six coal samples were taken from main coal mines of twenty-six provinces,autonomous regions,and municipalities in China,according to the resource distribution and coal-forming periods as well as the coal ranks and coal *** was determined by using the Kjeldahl method at *** Survey(USGS),which exhibit a normal frequency *** nitrogen contents of over 90% Chinese coal vary from 0.52% to 1.41% and the average nitrogen content is recommended to be 0.98%.Nitrogen in coal exists primarily in organic *** is a slight positive relationship between nitrogen content and coal ranking.

关键词： coal nitrogen distribution

End-Triassic nonmarine biotic events

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Journal of Palaeogeography 2015年第4期4卷 331-348页

作者： Spencer G.lucas Lawrence H.Tanner New Mexico Museum of Natural History Department of biological Sciences Le Moyne College

The Late Triassic was a prolonged interval of elevated extinction rates and low origination rates that manifested themselves in a series of extinctions during Carnian, Norian and rhaetian time. Most of these extinctions took place in the marine realm, particularly affecting radiolarians, conodonts, bivalves, ammonoids and reef-building organisms. On land, the case for a Late Triassic mass extinction is much more tenuous and has largely focused on tetrapod vertebrates（amphibians and reptiles）, though some workers advocate a sudden endTriassic（TJb） extinction of land plants. Nevertheless, an extensive literature does not identify a major extinction of land plants at the TJb, and a comprehensive review of palynological records concluded that TJb vegetation changes were non-uniform（different changes in different places）, not synchronous and not indicative of a mass extinction of land plants. Claims of a substantial perturbation of plant ecology and diversity at the TJb in East Greenland are indicative of a local change in the paleoflora largely driven by lithofacies changes resulting in changing taphonomic filters. Plant extinctions at the TJb were palaeogeographically localized events, not global in extent. With new and more detailed stratigraphic data, the perceived TJb tetrapod extinction is mostly an artifact of coarse temporal resolution, the compiled correlation effect. The amphibian, archosaur and synapsid extinctions of the Late Triassic are not concentrated at the TJb, but instead occur stepwise, beginning in the Norian and extending into the Hettangian. There was a disruption of the terrestrial ecosystem across the TJb, but it was more modest than generally claimed. The ecological severity of the end-Triassic nonmarine biotic events are relatively low on the global scale. biotic turnover at the end of the Triassic was likely driven by the CAMP（Central Atlantic Magmatic Province） eruptions, which caused significant environmental perturbations（cooling, warming,

关键词： Triassic-Jurassic boundary mass extinction land plants East Greenland tetrapods Newark Supergroup CAMP volcanism

Paleosols of the upper Paleozoic Sangre de Cristo Formation,north-central New Mexico:record of early Permian palaeoclimate in tropical Pangaea

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Journal of Palaeogeography 2017年第2期6卷 144-161页

作者： Lawrence H. Tanner Spencer G. lucas Department of biological Sciences Le Moyne CollegeSyracuseNY 13214USA New Mexico Museum of Natural History 1801 Mountain Road N.W.AlbuquerqueNM 87014USA

The lower Permian(Wolfcampian) Sangre de Cristo Formation of northern New Mexico consists of silty mudstones and laterally discontinuous sandstones deposited on an aggrading alluvial ***,mudstones display a variety of pedogenic *** mudstone fabrics vary from platy to prismatic;some beds display prominent pedogenic ***-colored root traces are common throughout the section,as are calcareous nodules,which vary from small bodies with diffuse boundaries to vertically stacked,discrete,cm-scale nodules(rhizocretions),and less commonly form coalescing *** occur only in the lower portion of the ca.90-m measured *** of the mudstone beds contain calcretes that are immature(calcic Protosols to calcic Argillisols),but the lower to middle portion of the section also contains mature calcrete horizons(argillic Calcisols and Calcisols).Intercalated micritic limestone beds with sharp contacts containing root traces,are of laterally variable thickness and grade to nodular *** are interpreted as floodplain pond carbonates that have undergone pedogenic alteration(palustrine limestones),indicating long periods of exposure under strongly seasonal climatic *** isotopic composition of the pedogenic carbonate displays a substantial range of values,but most of the range of variation in isotopic composition is accounted for by isotopically heavier carbonate(both carbon and oxygen) precipitated in shallow ponds subject to intense pedogenic reworking(palustrine carbonate).During the early Permian,northern New Mexico was situated in a near equatorial position(ca.4° N).The overall character of the paleosols suggests a persistent warm,semi-humid,seasonal climate throughout most of the interval of deposition during the Wolfcampian,but with episodically increased aridity during formation of the more mature *** long-term trend of climate change is evident in the stratigraphic section examined for this study.

关键词： Sangre de Cristo Formation Wolfcampian Vertisol Argillisol Calcisol Protosol

Turbulent flow in converging nozzles,part one:boundary layer solution

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Applied Mathematics and Mechanics(English Edition) 2011年第5期32卷 645-662页

作者： r.MADDAHIAN b.FArHANIEH b.FIrOOZAbADI Center of Excellence in Energy Conversion School of Mechanical Engineering Sharif University of Technology

The boundary layer integral method is used to investigate the development of the turbulent swirling flow at the entrance region of a conical nozzle. The governing equations in the spherical coordinate system are simplified with the boundary layer as- sumptions and integrated through the boundary layer. The resulting sets of differential equations are then solved by the fourth-order Adams predictor-corrector method. The free vortex and uniform velocity profiles are applied for the tangential and axial velocities at the inlet region, respectively. Due to the lack of experimental data for swirling flows in converging nozzles, the developed model is validated against the numerical simulations. The results of numerical simulations demonstrate the capability of the analytical model in predicting boundary layer parameters such as the boundary layer growth, the shear rate, the boundary layer thickness, and the swirl intensity decay rate for different cone angles. The proposed method introduces a simple and robust procedure to investigate the boundary layer parameters inside the converging geometries.

关键词： swirling flow converging nozzle swirl intensity decay rate boundary layer integral method analytical solution

The engineered eyeball, a tunable imaging system using soft-matter micro-optics

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Light(Science & Applications) 2016年第1期5卷 848-854页

作者： Sebastian Petsch Stefan Schuhladen lucas Dreesen Hans Zappe Department of Microsystems Engineering University of Freiburg79110 FreiburgGermany

We demonstrate a tunable imaging system based on the functionality of the mammalian eye using soft-matter micro-optical *** by the structure of the eye,as well as by the means through which nature tunes its optical behavior,we show that the technologies of microsystems engineering and micro-optics may be used to realize a technical imaging system whose biomimetic functionality is entirely distinct from that of conventional *** engineered eyeball integrates a deformable elastomeric refractive structure whose shape is mechanically controlled through application of strain using liquid crystal elastomer(LCE)actuators;two forms of tunable iris,one based on optofluidics and the other on LCEs with embedded heaters;a fixed lens arrangement;and a commercial imaging sensor *** complete microsystem,optimized to yield optical characteristics close to those of the human eye,represents the first fully functional,soft-matter-based tunable single-aperture eye-like imager.

关键词： imaging systems liquid-crystal elastomers micro-optics optofluidics

Systemic risks: A Homomorphic Approach on the basis of Complexity Science

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International Journal of Disaster risk Science 2018年第3期9卷 292-305页

作者： Klaus lucas Ortwin renn Carlo Jaeger Saini Yang Institute of Technical Thermodynamics Aachen University Institute for Advanced Sustainability Studies (IASS) Economic and Social Science Department University of Stuttgart Academy of Disaster reduction and Emergency Management School of Geography Beijing Normal University Global Climate Forum Key Laboratory of Environmental Change and Natural Disasters Ministry of Education Beijing Normal University

Although the notion of systemic risk gained prominence with respect to financial systems, it is a generic term that refers to risks of increasing importance in many domains—risks that cannot be tackled by conventional techniques of risk management and governance. We build on a domain-overarching definition of systemic risks by highlighting crucial properties that distinguish them from conventional risks and plain disasters. references to typical examples from various domains are included. Common features of systemic risks in different domains—such as the role of agents and emergence phenomena, tipping and cascading, parameters indicating instability, and historicity—turn out to be more than noncommittal empirical observations. rather these features can be related to fundamental theory for relatively simple and well-understood systems in physics and chemistry. A crucial mechanism is the breakdown of macroscopic patterns of whole systems due to feedback reinforcing actions of agents on the microlevel, where the reinforcement is triggered by boundary conditions moving beyond critical tipping *** the whole article, emphasis is placed on the role of complexity science as a basis for unifying the phenomena of systemic risks in widely different domains.

关键词： Complexity science Integrated risk governance Multiagent modeling Systemic risks