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Early Paleozoic tectonics of Asia:Towards a full-plate model

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Geoscience Frontiers 2018年第3期9卷 789-862页

作者： Mathew Domeier centre for Earth Evolution and dynamics University of Oslo

Asia is key to a richer understanding of many important lithospheric processes such as crustal growth,continental evolution and orogenesis. But to properly decipher the secrets Asia holds, a first-order tectonic context is needed. This presents a challenge, however, because a great variety of alternative and often contradictory tectonic models of Asia have flourished. This plethora of models has in part arisen from efforts to explain limited observations(in space, time or discipline) without regard for the broader assemblage of established constraints. The way forward, then, is to endeavor to construct paleogeographic models that fully incorporate the diverse constraints available, namely from quantitative paleomagnetic data, the plentiful record of geologic and paleobiologic observations, and the principles of plate tectonics. This paper presents a preliminary attempt at such a synthesis concerning the early Paleozoic tectonic history of Asia. A review of salient geologic observations and paleomagnetic data from the various continental blocks and terranes of Asia is followed by the presentation of a new, full-plate tectonic model of the region from middle Cambrian to end-Silurian time(500-420 Ma). Although this work may serve as a reference point, the model itself can only be considred provisional and ideally it will evolve with time. Accordingly, all the model details are released so that they may be used to test and improve the framework as new discoveries unfold.

关键词： Tectonics Asia Early Paleozoic Paleogeography Paleomagnetism

Vegetable Production After Flooded Rice Improves Soil Properties in the Red River Delta, Vietnam

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Pedosphere 2015年第1期25卷 130-139页

作者： Arij P.EVERAARTS Jacques J.NEETESON Pham T.T.HUONG Paul C.STRUIK applied Plant research Wageningen University and Research Centre Plant research International Wageningen University and Research Centre Field Crop research Institute Hai Duong and Hanoi University of Agriculture centre for Crop Systems Analysis Wageningen University

Vegetable production in South East Asia often is in rotation with flooded rice. The puddling of the soil with flooded rice production may result in unfavourable soil conditions for the subsequent production of dry land crops. To establish whether permanent vegetable production results in favourable soil conditions for vegetables, the effects of five different permanent vegetable production systems and a system of vegetable production in rotation with flooded rice on soil properties after flooded rice were studied in a 2-year field experiment. Bulk density at 0.05–0.10 m depth layer decreased with permanent vegetable production and vegetable production in rotation with flooded rice. The decrease in bulk density was influenced by the application of organic manure and rice husks, and especially by the number of crops cultivated, suggesting that frequency of soil tillage had a major effect on bulk density. Ploughing with buffalo traction after flooded rice, in combination with construction of raised beds, could reduce or totally eliminate negative effects of puddling on soil structure. Bulk density at 0.15–0.20 m soil depth was not influenced. Soil acidity decreased significantly in all systems. Soil organic carbon increased in all systems, but significant increase was only found in two permanent vegetable production systems. Available phosphorus(P) significantly increased in two permanent vegetable production systems, with a positively correlation to the amount of P applied. The significant decrease in bulk density and increase in p H(H2O), after only 2 years, showed that soil conditions after flooded rice could be improved in a short time under intensive vegetable production.

关键词： available phosphorus bulk density organic carbon puddling soil fertility soil improvement

Hopf Bifurcations for the Recently Proposed Smooth-and-Discontinuous Oscillator

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Chinese Physics Letters 2010年第7期27卷 172-175页

作者：田瑞兰曹庆杰李志新 centre for Nonlinear dynamics research Shijiazhuang Tiedao University Shijiazhuang 050043 School of Astronautics Harbin Institute of Technology Harbin 150001

We investigate the Hopf bifurcations of the recently proposed smooth-and-discontinuous （SD） oscillator which exhibits both smooth and discontinuous dynamics depending on the value of a parameter a. The nonlinearity presented in this system characterizes irrationality and piecewise linearity for smooth and discontinuous cases, respectively, which could not meet the requirements of the conventional methods due to the barrier of Taylor expansion. Introducing a series of new kinds of elliptic integrals of the first and second kind to the perturbed oscillator, we obtain the Poincare-Birchoff normal forms of Hopf bifurcations for both smooth and discontinuous regimes. We also demonstrate the criteria for the occurrence of Hopf bifurcations, the stability of periodic solutions bifurcating from the equilibria and the excellent agreement between the theoretical and numerical results.

关键词： BIFURCATION theory NONLINEAR oscillators ANALYTICAL mechanics SMOOTHING (Numerical analysis) FORMS (Mathematics) ELLIPTIC functions

Holocene climate change in the Central Tibetan Plateau inferred by lacustrine sediment geochemical records

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Science China Earth Sciences 2007年第10期50卷 1548-1555页

作者： Andreas LüCKE Bernd WüNNEMANN Institute of Chemistry and dynamics of the Geosphere V: Sedimentary Systems Research Centre Jülich D-52425 Jülich Ger- many Interdisciplinary centre Ecosystem dynamics in Central Asia Freie Universitaet Berlin 12249 Berlin Germany

Multi-proxies of lacustrine sediments, such as total carbon (TC), total organic carbon (TOC), total inorganic carbon (TIC), total nitrogen (TN), total sulfur (TS), hydrogen index (HI), oxygen index (OI) and stable carbon isotopic composition of organic matter (δ^(13)C_(org)), were analyzed using a 7.3 m core from Zige Tangco. The source of the organic matter in the sediment was mainly from autochthonous phyto-plankton, therefore the significances of proxies can be interpreted as that high TOC, TOC/TS, HI and δ^(13)C_(org) values, low TC, TIC values corresponded to warm and wet climatic condition, and vice versa. The process of climatic development in the Zige Tangco region was hence recovered. During the early and Mid-Holocene, the climate was warm and wet and intensive cold events occurred during the periods of 8600 to 8400 cal a BP and 7400 to 7000 cal a BP. In the second half of Holocene, the climate became cold and dry gradually. The palaeoclimatic process during Holocene in Zige Tangco region matched well with that in Co Ngoin region which is ca 40 km to the south-east. Therefore this palaeoclimatic process represents the Holocene climatic feature in the Central Tibetan Plateau which has the same pattern in the Northern Tibetan Plateau, but the time and duration of some climatic events might be different. We can conclude that in Holocene solar insolation controlled the climatic pattern on the central Tibetan Plateau.

关键词： lacustrine sediment hydrogen index (HI) stable carbon isotopic composition (δ^(13)C_(org)) palaeoclimate Central Tibetan Plateau

Shock wave velocity measurement in the Al_2O_3 under ultrahigh pressure

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Chinese Physics B 2011年第6期20卷 307-312页

作者：王峰彭晓世刘慎业李永升蒋小华丁永坤 research centre of Laser Fusion Chinese Academy of Engineering Physics Institute of applied Physics and Computational Mathematics

in indirect-drive experiment, the blank effect caused by X-rays from Hohlraum will show the dark area in time scale of optical streak camera （OSC）. This blank effect, which was a serious problem in indirect-drive shock wave experiments, has been explained by the semiconductor model. The X-rays cause the band to band transition and the probe laser is absorbed by the intraband transition, which leads to a dark region in time scale of the OSC image. In the experiment, the reflectivity of shock wave front was measured to be about 50% at shock wave velocity 32 km/s and was compared to the theoretical calculations with the Drude free electron model. From the experimental data, it is found that the blank effect can be avoided at radiation temperature of 170 eV if the Al layer is thicker than 60μm.

关键词： shock wave optical diagnosis interfere meter semiconductor model

The N-formyl peptide receptors: contemporary roles in neuronal function and dysfunction

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Neural Regeneration research 2020年第7期15卷 1191-1198页

作者： Peter J.G. Cussell Margarita Gomez Escalada Nathaniel G.N. Milton Andrew W.J. Paterson centre for Biomedical Science research School of Clinical and Applied Sciences Leeds Beckett University

N-formyl peptide receptors(FPRs)were first identified upon phagocytic leukocytes,but more than four decades of research has unearthed a plethora of non-myeloid roles for this receptor *** are expressed within neuronal tissues and markedly in the central nervous system,where FPR interactions with endogenous ligands have been implicated in the pathophysiology of several neurodegenerative diseases including Alzheimer's disease and Parkinson's disease,as well as neurological cancers such as *** the homeostatic function of FPRs in the nervous system is currently undefined,a variety of novel physiological roles for this receptor family in the neuronal context have been posited in both human and animal *** developments in recent years have implicated FPRs in the process of neurogenesis and neuronal differentiation which,upon greater characterisation,could represent a novel pharmacological target for neuronal regeneration therapies that may be used in the treatment of brain/spinal cord injury,stroke and *** review aims to summarize the recent progress made to determine the physiological role of FPRs in a neuronal setting,and to put forward a case for FPRs as a novel pharmacological target for conditions of the nervous system,and for their potential to open the door to novel neuronal regeneration therapies.

关键词： Alzheimer's disease formyl peptide receptor neural regeneration neuroblastoma neurodegeneration neuroinflammation neuronal differentiation stroke

An updated systematic review of Zika virus-linked complications

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Asian Pacific Journal of Tropical Medicine 2018年第1期11卷 1-8页

作者： Braira Wahid Amjad Ali Muhammad Waqar Muhammad Idrees centre for applied Molecular Biology University of the Punjab Genome centre for Molecular Based Diagnostics and research centre Hazara University

Objective: To determine the breadth of Zika virus(ZIKV)-associated brain anomalies in neonates and adults. Methods: Systematic review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA) statement using electronic databases ScienceDirect, Pubmed, Medline, Scopus, and Global Health *** those research articles, case studies, case-control studies, case-cohort studies, crosssectional studies, and organizational survey reports were included in the study that reported any fetal outcomes for pregnant women who had infected with ZIKV during the gestational period and ZIKV-related neurological complications in adults as well. Results: Out of total 72 retrieved articles, 50 met the inclusion criteria. We estimated a significant increase in incidence of neural abnormalities such as Guillain-Barre syndrome and microcephaly in the regions that are experiencing ZIKV outbreaks. Other neurological malformations found in ZIKV patients include hydrancephaly/hydrops fetalis, myasthenia gravis,meningoencephalitis and myelitis. Conclusion: Our systematic analysis provides the broad spectrum of neurological malformations in ZIKV infected patients and these data further support the causal link of ZIKV with neurological disorders.

关键词： Zika virus Microcephaly Guillain-Barre syndrome Acute myelitis Meningoencephalitis hydrancephaly/hydrops fetalis Myasthenia gravis

Stability of turning processes for periodic chip formation

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Advances in Manufacturing 2018年第3期6卷 345-353页

作者： Gergely Gyebrószki Daniel Bachrathy Gábor Csernák Gabor Stepan Department of applied Mechanics Budapest University ofTechnology and Economics Budapest Hungary MTA-BME research Group on dynamics of Machines and Vehicles Budapest Hungary

The prediction of chatter vibration is influencedby many known complex phenomena and is uncertain. Wepresent a new effect that can significantly change the sta-bility properties of cutting processes. It is shown that themicroscopic environment of chip formation can have alarge effect on its macroscopic properties. In this work, acombined model of the surface regeneration effect and chipformation is used to predict the stability of turning pro-cesses. In a chip segmentation sub-model, the primaryshear zone is described with a corresponding materialmodel along layers together with the thermodynamicbehavior. The surface regeneration is modeled by the time-delayed differential equation. Numerical simulations showthat the time scale of a chip segmentation model is sig-nificantly smaller than the time scale of the turning process;therefore, averaging methods can be used. Chip segmen-tation can decrease the average shear force leading todecreased cutting coefficients because of the non-lineareffects. A proper linearization of the equation of motionleads to an improved description of the cutting *** is shown that chip segmentation may significantlyincrease the stable domains in the stability charts; fur-thermore, by selecting proper parameters, unbounded sta-bility domains can be reached.

关键词： Chip formation Chatter Turning delay

Metallic Functionally Graded Materials:A Specific Class of Advanced Composites

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Journal of Materials Science & Technology 2013年第4期29卷 297-316页

作者： Jerzy J.Sobczak Ludmil Drenchev Foundry research Institute KrakowPoland Institute of Metal Science Equipment and Technology with Hydro and Aero-dynamics CentreBulgarian Academy of SciencesSofaBulgaria

Functionally graded materials, including their characterization, properties and production methods are a new rapidly developing field of materials science. The aims of this review are to systematize the basic production techniques for manufacturing functionally graded materials. Attention is paid to the principles for obtaining graded structure mainly in the metal based functionally graded materials. Several unpublished results obtained by the authors have been discussed briefly. Experimental methods and theoretical analysis for qualitative and quantitative estimation of graded properties have also been presented. The article can be useful for people who work in the field of functionally graded structures and materials, and who need a compact informative review of recent experimental and theoretical activity in this area.

关键词： Functionally graded materials Production techniques Theoretical analysis