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Are hyoliths Palaeozoic lophophorates?

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National Science Review 2020年第2期7卷 453-469页

作者： Fan Liu christian b Skovsted Timothy P Topper Zhifei Zhang Degan Shu State Key Laboratory of Continental Dynamics Shaanxi Key Laboratory of Early Life and Environments Department of Geology Northwest University Department of Palaeobiology Swedish Museum of Natural History

The phylogenetic position of hyoliths has long been unsettled, with recent discoveries of a tentaculate feeding apparatus(‘lophophore’) and fleshy apical extensions from the shell(‘pedicle’) suggesting a lophophorate affinity. Here, we describe the first soft parts associated with the feeding apparatus of an orthothecid hyolith, Triplicatella opimus from the Chengjiang biota of South China. The tuft-like arrangement of the tentacles of T. opimus differs from that of hyolithids, suggesting they collected food directly from the substrate. A reassessment of the feeding organ in hyolithids indicates that it does not represent a lophophore and our analysis of the apical structures associated with some orthothecids show that these represent crushed portions of the shell and are not comparable to the brachiopod pedicle. The new information suggests that hyoliths are more likely to be basal members of the lophotrochozoans rather than lophophorates closely linked with the Phylum brachiopoda.

关键词： orthothecid the Chengjiang Lagerst¨atte Cambrian soft parts lophophore

Schrodinger and Klein-Gordon theories of black holes from the quantization of the Oppenheimer and Snyder gravitational collapse

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Communications in Theoretical Physics 2023年第9期75卷 122-135页

作者： christian Corda SUNY Polytechnic Institute 13502 UticaNew YorkUSAIstituto Livi59100 PratoTuscanyItaly and International Institute for Applicable Mathematics and Information SciencesB M Birla Science CentreAdarshnagarHyderabad 500063India

The Schrodinger equation of the Schwarzschild black hole(bH) has been recently derived by the author and collaborators. The bH is composed of a particle, the 'electron', interacting with a central field, the 'nucleus'. Via de broglie's hypothesis, one interprets the 'electron' in terms of bH horizon's modes. Quantum gravity effects modify the bH semi-classical structure at the Schwarzschild scale rather than at the Planck scale. The analogy between this bH Schrodinger equation and the Schrodinger equation of the s states of the hydrogen atom permits us to solve the same equation. The quantum gravitational quantities analogous of the fine structure constant and of the Rydberg constant are not constants, but the dynamical quantities have well-defined discrete spectra. The spectrum of the 'gravitational fine structure constant' is the set of non-zero natural numbers. Therefore, bHs are well-defined quantum gravitational systems obeying Schrodinger's theory: the 'gravitational hydrogen atoms'. by identifying the potential energy in the bH Schrodinger equation as being the gravitational energy of a spherically symmetric shell, a different nature of the quantum bH seems to surface. bHs are self-interacting, highly excited,spherically symmetric, massive quantum shells generated by matter condensing on the apparent horizon, concretely realizing the membrane paradigm. The quantum bH described as a'gravitational hydrogen atom' is a fictitious mathematical representation of the real, quantum bH, a quantum massive shell having a radius equal to the oscillating gravitational *** consequences emerge from this result:(i) bHs have neither horizons nor singularities;(ii) there is neither information loss in bH evaporation, nor bH complementarity, nor firewall paradox. These results are consistent with previous ones by Hawking, Vaz, Mitra and ***, the special relativistic corrections to the bH Schrodinger equation give the bH Klein–Gordon equation and the cor

关键词： quantum black holes information paradox quantum shells quantum levels Schrodinger and Klein-Gordon theories

TMPRSS2,a novel host-directed drug target against SARS-CoV-2

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Signal Transduction and Targeted Therapy 2022年第8期7卷 2665-2667页

作者： christian Keller Eva böttcher-Friebertshäuser Michael Lohoff Institute of Virology Philipps University MarburgMarburgGermany Institute of Medical Microbiology and Hygiene Philipps University MarburgMarburgGermany

In a recent study in Nature,1 Shapira et *** that the peptidomimetic compound N-0385 inhibited SARS-CoV-2 infection in vitro in remarkably low concentrations by blocking the host cell protease TMPRSS2,which mediates proteolytic cleavage of the SARS-CoV-2 major surface glycoprotein spike(S).Accordingly,N-0385 protected experimentally infected mice from severe SARS-CoV-2 pathology.

关键词： directed protected cleavage

Experimental studies on the energy dissipation of bolted structures with frictional interfaces:A review

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Friction 2024年第8期12卷 1623-1654页

作者： Yongfeng WANG Yanhong MA Jie HONG Giuseppe b.ATTIATO christian M.FIRRONE School of Energy and Power Engineering Beihang UniversityBeijing 102206China Research Institute of Aero-Engine Beihang UniversityBeijing 102206China Politecnico di Torino Department of Mechanical and Aerospace EngineeringTorino 10139Italy

bolted joints play a more and more important role in the structure with lighter weight and heavier *** paper aims to provide an overview of different experimental approaches for the dynamic behavior of structures in the presence of bolted joints,especially the energy dissipation or damping at frictional *** comprehension of energy dissipation mechanisms due to friction is provided first,while the key parameters and the measurement techniques,such as the excitation force,the preload of the bolt,or the pressure at the interfaces,are briefly ***,the round-robin systems aim to measure the hysteresis parameters of the frictional joints under tangential loads are reviewed,summarizing the basic theory and the strategies to apply the excitation force or acquire the response in different testing *** by parameter identification strategies for bolted structures,the test rigs with one or more simplified bolted joints are summarized to give an insight into the understanding of typical characteristics of bolted structures,which are affected by the presence of *** complex test rigs hosting real-like or actual engineering structures with bolted lap or flange joints are also introduced to show the identification process of the dynamic characteristics of bolted connections employed in specific *** on the review paper,researchers can get the basic knowledge about the experimental systems of the bolted structures,especially several classical round robin systems,such as the Gaul resonator and widely used brake-Reußbeam *** can take advantage of this background for more creative and effective future studies,make more progress on the study of assembled structures and understand the influence of bolting frictional connections on the dynamic response better.

关键词： review study bolted joints frictional damping experimental rigs measurements

Insensitive high explosives:Ⅳ. Nitroguanidine-Initiation & detonation

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Defence Technology（防务技术） 2019年第4期15卷 467-487页

作者： Ernst-christian Koch Lutradyn-Energetic Materials

This paper reviews the detonative properties of low bulk density(LbD),high bulk density(HbD)Nitroguanidine(NGu)(1),CAS-No:[556-88-7]and 82 explosive formulations based on NGu reported in the public *** rank the performance of those formulations they are compared with 15 reference compositions containing both standard high explosives such as octogen(HMX)(2),hexogen(RDX)(3),pentaerythritol tetranitrate(PETN)(4),2,4,6-trinitrotoluene(TNT)(5)as well as insensitive high explosives such as 3-nitro-1,2,4-triazolone(NTO)(6),1,3,5-triamino-2,4,6-trinitrobenzene(TATb)(7),1,1-diamino-2,2-dinitroethylene(FOX-7)(8)and N-Guanylurea dinitramide(FOX 12)(9).NGu based formulations are superior to those based on FOX-12 or TATb and are a close match with FOX-7 based explosives,the latter just having higher Gurney Energies(-10%)and slightly higher detonation pressure(+2%).NGu based explosives even reach up to 78% of the detonation pressure,82% Gurney energy and up to 95% of detonation velocity of ***-NGu dissolves in many melt cast eutectics forming dense charges thereby eliminating the need for costly High bulk Density *** based formulations are at the rock bottom of sensitiveness among all the above-mentioned explosives which contributes to the safety of these *** review gives 132 references to the public *** a review on the synthesis spectroscopy and sensitiveness of Nitroguanidine see Ref.[1].

关键词： Cook-off Detonation Insensitive munitions Nitroguanidine Shock sensitvity

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Special materials in pyrotechnics Ⅶ: Pyrotechnics used in thermal batteries

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Defence Technology（防务技术） 2019年第3期15卷 254-263页

作者： Ernst-christian Koch Lutradyn Energetic Materials Science & Technology

Thermal batteries are unique direct current(DC) electrical power sources with long shelf live, high reliability and higher power density than classical alkaline batteries. This paper gives a brief overview into the working principle of thermal batteries and reviews the properties of zirconium/barium chromate(Zr/baCrO4) pyrolant previously used as first fire and iron/potassium perchlorate(Fe/KClO4) pyrolant(Heat), commonly applied as heating pellet in thermal batteries and its hazard properties. The review gives 64 references to the public domain. CAS-Nos. Zr: [7440-67-7], baCrO4: [10294-40-3], Fe: [7439-89-6], KClO4: [7778-74-7], Viton: [9011-17-0].CAS-Nos. Zr: [7440-67-7], baCrO4: [10294-40-3], Fe: [7439-89-6], KClO4: [7778-74-7], Viton: [9011-17-0].

关键词： barium chromate Heat-powder Iron Lithium Molten salt Potassium perchlorate Pyrotechnics Thermal battery Zirconium

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Deep learning for geometric and semantic tasks in photogrammetry and remote sensing

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Geo-Spatial Information Science 2020年第1期23卷 10-19页

作者： christian Heipke Franz Rottensteiner Institute of Photogrammetry and GeoInformation(PI) Leibniz University HannoverHannoverGermany

During the last few years,artificial intelligence based on deep learning,and particularly based on convolutional neural networks,has acted as a game changer in just about all tasks related to photogrammetry and remote *** have shown partly significant improvements in many projects all across the photogrammetric processing chain from image orientation to surface reconstruction,scene classification as well as change detection,object extraction and object tracking and recognition in image *** paper summarizes the foundations of deep learning for photogrammetry and remote sensing before illustrating,by way of example,different projects being carried out at the Institute of Photogrammetry and GeoInformation,Leibniz University Hannover,in this exciting and fast moving field of research and development.

关键词： Deep learning machine learning convolutional neural networks(CNN) example project from IPI

Intranasal neprilysin rapidly eliminates amyloid-beta plaques, but causes plaque compensations: the explanation why the amyloid-beta cascade may fail?

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Neural Regeneration Research 2022年第9期17卷 1881-1884页

作者： christian Humpel Laboratory of Psychiatry and Experimental Alzheimer’s Research Medical University of InnsbruckInnsbruckAustria

Neurodegenerative brain disorders are a major burden in our society,such as Alzheimer´s *** order to repair or prevent such diseases,drugs are designed which enter the brain,but the blood-brain barrier limits their entry and the search for alternative pathways is ***,we reported that intranasal delivery of the amyloid-beta degrading enzyme neprilysin eliminated amyloid-beta plaques in transgenic Alzheimer´s disease *** review describes the anatomical structure of the intranasal pathway,explains the intranasal delivery of pure neprilysin,cell-loaded neprilysin(platelets)and collagen-embedded neprilysin to destruct amyloid-beta plaques in Alzheimer´s disease in transgenic APP_SweDI mice and hypothesizes why this may cause compensation and why the amyloid-beta cascade hypothesis may fail.

关键词： amyloid-beta amyloid-beta degrading enzyme clear plaque collagen biomaterial intranasal neprilysin nose-to-brain

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Cross-Talk between ROS and Calcium in Regulation of Nuclear Activities

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Molecular Plant 2010年第4期3卷 706-718页

作者： christian Mazars Universite de Toulouse UPS UMR 5546 Surfaces Cellulaires et Signalisation chez les Vegetaux BP 42617 F-31326 Castanet-Tolosan France CNRS UMR 5546 BP 42617 F-31326 Castanet-Tolosan France Universite de bourgogne UMR Plante-Microbe-Environnement BP 86510 21065 Dijon cedex France UMR INRA 1088 CNRS 5184 Universite de Bourgogne Plante-Microbe-Environnement BP 86510 21065 Dijon cedex France

Calcium and Reactive Oxygen Species （ROS） are acknowledged as crucial second messengers involved in the response to various biotic and abiotic stresses. However, it is still not clear how these two compounds can play a role in different signaling pathways leading the plant to a variety of processes such as root development or defense against pathogens. Recently, it has been shown that the concept of calcium and ROS signatures, initially discovered in the cytoplasm, can also be extended to the nucleus of plant cells. In addition, it has been clearly proved that both ROS and calcium signals are intimately interconnected. How this cross-talk can finally modulate the translocation and/or the activity of nuclear proteins leading to the control of specific genes expression is the main focus of this review. We will especially focus on how calcium and ROS interact at the molecular level to modify their targets.

关键词： Nucleus Calcium ROS Crosstalk Signalling.