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On the Identity and Taxonomic Status of Coluber nuthalli Theobald, 1868, with Redescription of the Type Specimens of Coluber nuthalli and Elaphis yunnanensis Anderson, 1879(Reptilia, Squamata, Colubridae)

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Asian Herpetological Research 2015年第1期6卷 1-10页

作者： klaus Dieter SCHULZ Frank TILLACK Abhijit DAS Notker HELFENBERGER An Kuckum5a 52146 Würselen Germany Museum für Naturkunde Leibniz Institute for Evolution and Biodiversity Science Invalidenstrαβe 43 D-10115 Berlin Germany Wildlife Institute of India Chandrabani Dehradun India Kasereistrasse4 9305 Berg SG Switzerland

The taxaColuber nuthalli Theobald, 1868 andElaphis yunnanensis Anderson, 1879 are compared and re-described, based on the examination of their type material. The morphological similarities of these two taxa revealed them as *** yunnanensis Anderson is thus declared as a protected name （nomen conservandum） with priority overC. nuthalli Theobald （nomen oblitum）. A lectotype forElaphis yunnanensis is designated and described. The validity ofyunnanensis as subspecies name in combination withOrthriophis taeniurus （Cope） will be discussed. A key to the subspecies ofO. taeniurus is provided.

关键词： Reptilia Serpentes Colubridae Elaphisyunnanensis Anderson (nomen protectum) Coluber nuthalli Theobald (nomen oblitum) Elapheauct. Orthriophis taeniurus yunnanensis taxonomy morphology China Myanmar

Climate change effects in the Western Himalayan ecosystems of India: evidence and strategies

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Forest Ecosystems 2017年第3期4卷 232-240页

作者： Vindhya Prasad Tewari Raj Kumar Verma klaus von Gadow Himalayan Forest Research Institute Georg-August University Department of Forestry and Wood Science University of Stellenbosch

Background： The fragile landscapes of the Himalayan region are highly susceptible to natural hazards, and there is ongoing concern about current and potential climate change impacts. This study provides background information on India＇s Western Himalayas and reviews evidence of warming as well as variability in precipitation and extreme ***： Understanding and anticipating the impacts of climate change on Himalayan forest ecosystems and the services they provide to people are critical. Efforts to develop and implement effective policies and management strategies for climate change mitigation and adaptation requires particular new research initiatives. The various studies initiated and conducted in the region are compiled ***： Several new initiatives taken by the Himalayan Forest Research Institute in Shimla are described. This includes new permanent observational field studies, some with mapped trees, in high altitude transitional zones for continuous monitoring of vegetation response. We have also presented new strategies for mitigating potential climate change effects in Himalayan forest ***： Assessment of the ecological and genetic diversity of the Himalayan conifers is required to evaluate potential responses to changing climatic conditions. Conservation strategies for the important temperate medicinal plants need to be developed. The impact of climate change on insects and pathogens in the Himalayas also need to be assessed. Coordinated efforts are necessary to develop effective strategies for adaptation and mitigation.

关键词： Himalayan ecosystem Climate change New strategies High altitude New observational studies

Specific changes in the expression of imprinted genes in prostate cancer--implications for cancer progression and epigenetic regulation

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Asian Journal of Andrology 2012年第3期14卷 436-450,I0007页

作者： Teodora Ribarska klaus-Marius Bastian Annemarie Koch Wolfgang A Schulz Department of Urology Heinrich Heine University 40225 Duesseldorf Germany 1

Epigenetic dysregulation comprising DNA hypermethylation and hypomethylation, enhancer of zeste homologue 2 （EZH2） overexpression and altered patterns of histone modifications is associated with the progression of prostate cancer. DNA methylation, EZH2 and histone modifications also ensure the parental-specific monoallelic expression of at least 62 imprinted genes. Although it is therefore tempting to speculate that epigenetic dysregulation may extend to imprinted genes, expression changes in cancerous prostates are only well documented for insulin-like growth factor 2 （IGF2）. A literature and database survey on imprinted genes in prostate cancer suggests that the expression of most imprinted genes remains unchanged despite global disturbances in epigenetic mechanisms. Instead, selective genetic and epigenetic changes appear to lead to the inactivation of a sub-network of imprinted genes, which might function in the prostate to limit cell growth induced via the PI3K/Akt pathway, modulate androgen responses and regulate differentiation. Whereas dysregulation of IGF2 may constitute an early change in prostate carcinogenesis, inactivation of this imprinted gene network is rather associated with cancer progression.

关键词： androgen signalling imprinted genes loss of imprinting PI3K signalling prostate cancer

Arsenic in Rice Soils and Potential Agronomic Mitigation Strategies to Reduce Arsenic Bioavailability： A Review

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Pedosphere 2018年第3期28卷 363-382页

作者： Lalith D.B.SURIYAGODA klaus DITTERT Hans LAMBERS Faculty of Agriculture University of Peradeniya Peradeniya 20400( Sri Lanka) Department of Crop Science Section of Plant Nutrition and Crop Physiology University of Gottingen Gottingen 37075( Germany) School of Biological Sciences and Institute of Agriculture The University of Western Australia Perth WA 6009( Australia)

Soils used for rice （Oryza sativa L.） cultivation in some areas contain high concentrations of arsenic （As）due to irrigation with groundwater containing As and intensive use of agrochemicals or industrial residues containing As. To restrict rice uptake of As in these soils, approaches to reduce As input and bioavailability must be considered. One approach to reduce As input into rice soils or uptake by rice is cultivating rice under aerobic, intermittent flooding, or alternate wetting and drying （AWD） conditions, rather than in submerged soils, or use of irrigation water low in As. For reducing As bioavailability in soil, aerobic or AWD rice culture and application of biochar, sulfur （S）, and/or rice polish to soil are promising. Moreover, use of As-hyperaecumulating plant species （e.g., Pteris vittata L.） in rotation or combinations with favourable plant species （e.g., Azolla, Chlorella, or Nannochloropsis species） can also be promoted, in addition to using rice cultivars that are tolerant to As. Though applications of high doses of phosphorus （P）, iron （Fe）, and silicon （Si） fertilizers have shown promise in many instances, these methods have to be practiced carefully, because negative effects have also been reported, although such incidents are rare. Major factors affecting As speciation and bioavailability in soil are chemical properties such as redox status, pH, and Fe, P, Si, and S concentrations, physical properties such as texture and organic matter, and biological properties such as methylation activity by soil microorganisms. However, as many of these factors interact, long-term examination under field conditions is needed before measures are recommended for and implemented in farmers＇ fields.

关键词： amendment contaminated soils health risk hyperaccumulating plant remediation tolerant cultivar toxicity water management

Theoretical Study on Ion Escape in Martian Atmosphere

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Chinese Physics Letters 2007年第1期24卷 298-301页

作者：史建魁刘振兴 klaus TORKAR Tielong ZHANG State Key Laboratory for Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100080 Space Research Institute Austrian Academy of Sciences A-8042 Graz Austria

Based on the observation that Martian magnetic moment is gradually reducing from the ancient to the present, we investigate the O^＋ ion flux distribution along magnetic field lines and the ion escaping flux in Martian tail with different assumed Martian magnetic moments. The results show that the O^＋ ion flux along magnetic field lines decreases with distance from Mars; the ion flux along the field line decreases more quickly if the magnetic moment is larger; the larger the magnetic moment, the smaller the ion escaping flux in the Martian tail. The ion escaping flux depends on Z-coordinate in the Martian tail. With decrease of the magnetic moment, the ion escaping flux in the Martian tail increases. The results are significant for studying the water loss from Mars S uFface.

关键词： Mars surface Mars atmosphere Mars Mars magnetic field Ion fluxes Magnetic fields Ion escape

Approximation Algorithms for 3D Orthogonal Knapsack

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Journal of Computer Science & Technology 2008年第5期23卷 749-762页

作者： Florian Diedrich Rolf Harren klaus Jansen Ralf Thle Henning Thomas Institute of Computer Science University of Kiel Max-Planck-Institut für Informatik Campus E1466123 Saarbrücken Germany Department of Computer Science ETH ZurichZurich Switzerland

We study non-overlapping axis-parallel packings of 3D boxes with profits into a dedicated bigger box where rotation is either forbidden or permitted, and we wish to maximize the total profit. Since this optimization problem is NP-hard, we focus on approximation algorithms. We obtain fast and simple algorithms for the non-rotational scenario with approximation ratios 9 ＋ ε and 8 ＋ ε, as well as an algorithm with approximation ratio 7 ＋ ε that uses more sophisticated techniques; these are the smallest approximation ratios known for this problem. Furthermore, we show how the used techniques can be adapted to the case where rotation by 90° either around the z-axis or around all axes is permitted, where we obtain algorithms with approximation ratios 6 ＋ ε and 5 ＋ ε, respectively. Finally our methods yield a 3D generalization of a packability criterion and a strip packing algorithm with absolute approximation ratio 29/4, improving the previously best known result of 45/4.

关键词： approximation algorithm computational and structural complexity geometric configurations

Contemporaneous assembly of Western Gondwana and final Rodinia break-up:Implications for the supercontinent cycle

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Geoscience Frontiers 2017年第6期8卷 1431-1445页

作者： Sebastián Oriolo Pedro Oyhantcabal klaus Wemmer Siegfried Siegesmund Geoscience Center Georg-August-Universitat GottingenGoldschmidtstrae 337077 GottingenGermany Departamento de Geología Facultad de CienciasUniversidad de la RepúblicaMontevideoUruguay

Geological,geochronological and isotopic data are integrated in order to present a revised model for the Neoproterozoic evolution of Western *** the classical geodynamic scenario assumed for the period 800-700 Ma is related to Rodinia break-up and the consequent opening of major oceanic basins,a significantly different tectonic evolution can be inferred for most Western Gondwana *** cratons occupied a marginal position in the southern hemisphere with respect to Rodinia and recorded subduction with back-arc extension,island arc development and limited formation of oceanic crust in internal *** period was thus characterized by increased crustal growth in Western Gondwana,resulting from addition of juvenile continental crust along convergent *** contrast,crustal reworking and metacratonization were dominant during the subsequent assembly of *** Rio de la Plata,Congo-Sao Francisco,West African and Amazonian cratons collided at ca.630-600 Ma along the West Gondwana *** events overlap in time with the onset of the opening of the Iapetus Ocean at ca.610-600 Ma,which gave rise to the separation of Baltica,Laurentia and Amazonia and resulted from the final Rodinia *** East African/Antarctic Orogen recorded the subsequent amalgamation of Western and Eastern Gondwana after ca.580 Ma,contemporaneously with the beginning of subduction in the Terra Australis Orogen along the southern Gondwana ***,the Kalahari Craton was lately incorporated during the Late Ediacaran-Early *** proposed Gondwana evolution rules out the existence of Pannotia,as the final Gondwana amalgamation postdates latest connections between Laurentia and ***,a combination of introversion and extroversion is proposed for the assembly of *** contemporaneous record of final Rodinia break-up and Gondwana assembly has major implications for the supercontinent cycle,as supercontinent amalgamation and break-

关键词： Brasiliano-Pan-African Orogeny Neoproterozoic Collisional tectonics Pannotia Metacratonization Introversion-extroversion

Collective effects for long bunches in dual harmonic RF systems

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Chinese Physics C 2008年第2期32卷 139-145页

作者：安世忠 klaus Bongardt Rudolf Maier 唐靖宇张天爵 China Institute of Atomic Energy Beijing 102413 China IKP FZ Juelich 52425 JuelichGermany Institute of High Energy Physics CAS Beijing 100049China

The storage of long bunches for large time intervals needs flattened stationary buckets with a large bucket height. Collective effects from the space charge and resistive impedance are studied by looking at the incoherent particle motion for the matched and mismatched bunches. Increasing the RF amplitude with particle number provides r.m.s wise matching for modest intensities. The incoherent motion of large amplitude particles depends on the details of the RF system. The resulting debunching process is a combination of the too small full RF acceptance together with the mismatch, enhanced by the collective effects. Irregular single particle motion is not associated with the coherent dipole instability. For the stationary phase space distribution of the Hofmann-Pedersen approach and for the dual harmonic RF system, stability limits are presented, which are too low if using realistic input distributions. For single and dual harmonic RF system with d=0.31, the tracking results are shown for intensities, by a factor of 3 above the threshold values. Small resistive impedances lead to coherent oscillations around the equilibrium phase value, as energy loss by resistive impedance is compensated by the energy gain of the RF system.

关键词： resistive impedance incoherent motion halo formation coherent dipole instability

Thrombolysis in acute stroke under dual antiplatelet therapy: perspectives arising from translational studies

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Neural Regeneration Research 2021年第1期16卷 113-114页

作者： Franziska Lieschke Yi Zheng Christian Foerch klaus van Leyen Neuroprotection Research Laboratory Massachusetts General HospitalHarvard Medical SchoolCharlestownMAUSA Department of Neurology University Hospital FrankfurtGoethe-UniversityFrankfurt am MainGermany

We have recently established a mouse model of focal stroke under dual antiplatelet therapy(DAPT)to study tissue plasminogen activator(tPA)-associated hemorrhagic *** purpose of this short perspective is to discuss the rationale for establishing the model,highlighting its relevance for addressing unresolved clinical *** conversion of the ischemic stroke remains one of the major liabilities of thrombolytic therapy with tPA,contributing to unfavorable outcomes and failed *** was recognized early on,and the resulting restrictions on tPA usage have led to only a minor percentage of stroke patients receiving any kind of drug treatment to limit ischemic injury.

关键词： DAPT hemorrhagic establishing