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High-Speed Trains Automatic Operation with Protection Constraints: A Resilient Nonlinear Gain-based Feedback Control Approach

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IEEE/CAA Journal of Automatica Sinica 2019年第4期6卷 992-999页

作者： Shigen Gao Yuhan Hou Hairong Dong sebastian Stichel Bin Ning IEEE the State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong UniversityBeijing 100044China the Division of Rail Vehicles KTH Royal Inititute of Technology

This paper addresses the control design for automatic train operation of high-speed trains with protection constraints.A new resilient nonlinear gain-based feedback control approach is proposed,which is capable of guaranteeing,under some proper non-restrictive initial conditions,the protection constraints control raised by the distance-to-go(moving authority)curve and automatic train protection in practice.A new hyperbolic tangent function-based model is presented to mimic the whole operation process of high-speed *** proposed feedback control methods are easily implementable and computationally inexpensive because the presence of only two feedback gains guarantee satisfactory tracking performance and closed-loop stability,no adaptations of unknown parameters,function approximation of unknown nonlinearities,and attenuation of external disturbances in the proposed control ***,rigorous proofs and comparative simulation results are given to demonstrate the effectiveness of the proposed approaches.

关键词： Automatic train operation high-speed train nonlinear gain feedback protection constraint resilient control

Raman spectroscopy of isolated carbyne chains confined in carbon nanotubes:Progress and prospects

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Chinese Physics B 2022年第12期31卷 532-542页

作者： Johannes M.A.Lechner Pablo Hernández López sebastian Heeg Institut fur Physik and IRIS Adlershof Humboldt Universitat zu Berlin12489 BerlinGermany

Carbyne is an infinitely long linear chain of carbon atoms with sp1hybridization and the truly one-dimensional allotrope of *** obtaining freestanding carbyne is still an open challenge,the study of confined carbyne,linear chains of carbon encapsulated in carbon nanotubes,provides a pathway to explore carbyne and its remarkable properties in a well-defined *** this review,we discuss the basics and recent advances in studying single confined carbyne chains by Raman spectroscopy,which is their primary spectroscopic characterization *** highlight where single carbyne chain studies are needed to advance our understanding of confined carbyne as a material system and provide an overview of the open questions that need to be addressed and of those aspects currently under debate.

关键词： carbyne linear carbon chains carbon nanotubes Raman spectroscopy

Single photon emission and recombination dynamics in self-assembled GaN/AlN quantum dots

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Light(Science & Applications) 2022年第5期11卷 751-765页

作者： Johann Stachurski sebastian Tamariz Gordon Callsen Raphaël Butté Nicolas Grandjean Institute of Physics École Polytechnique Fédérale de LausanneEPFLCH-1015 LausanneSwitzerland Present address:UniversitéCôte d’Azur CNRSCRHEAF-06560 ValbonneFrance Present address:Institut für Festkörperphysik Universität Bremen28359 BremenGermany

Ⅲ-nitride quantum dots(QDs)are a promising system actively studied for their ability to maintain single photon emission up to room ***,we report on the evolution of the emission properties of self-assembled GaN/AlN QDs for temperatures ranging from 5 to 300 *** carefully track the photoluminescence of a single QD and measure an optimum single photon purity of g^((2))(0)=0.05±0.02 at 5 K and 0.17±0.08 at 300 *** complement this study with temperature dependent time-resolved photoluminescence measurements(TRPL)performed on a QD ensemble to further investigate the exciton recombination dynamics of such polar zero-dimensional *** comparing our results to past reports,we emphasize the complexity of recombination processes in this *** of the more conventional mono-exponential decay typical of exciton recombination,TRPL transients display a bi-exponential feature with short-and long-lived components that persist in the low excitation *** the temperature insensitivity of the long-lived excitonic component,we first discard the interplay of dark-to-bright state refilling in the exciton recombination ***,this temperature-invariance also highlights the absence of nonradiative exciton recombinations,a likely direct consequence of the strong carrier confinement observed in GaN/AlN QDs up to 300 ***,our results support the viability of these dots as a potential single-photon source for quantum applications at room temperature.

关键词： temperature. process. quantum

The market for amino acids: understanding supply and demand of substrate for more efficient milk protein synthesis

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Journal of Animal Science and Biotechnology 2021年第1期12卷 37-48页

作者： Virginia L.Pszczolkowski sebastian I.Arriola Apelo Department of Animal and Dairy Sciences University of Wisconsin-MadisonMadisonWIUSA Endocrinology and Reproductive Physiology Graduate Training Program University of Wisconsin-MadisonMadisonWIUSA

For dairy production systems, nitrogen is an expensive nutrient and potentially harmful waste product. With three quarters of fed nitrogen ending up in the manure, significant research efforts have focused on understanding and mitigating lactating dairy cows' nitrogen losses. Recent changes proposed to the Nutrient Requirement System for Dairy Cattle in the US include variable efficiencies of absorbed essential AA for milk protein production. This first separation from a purely substrate-based system, standing on the old limiting AA theory, recognizes the ability of the cow to alter the metabolism of AA. In this review we summarize a compelling amount of evidence suggesting that AA requirements for milk protein synthesis are based on a demand-driven system. Milk protein synthesis is governed at mammary level by a set of transduction pathways, including the mechanistic target of rapamycin complex 1(mTORC1), the integrated stress response(ISR), and the unfolded protein response(UPR). In tight coordination, these pathways not only control the rate of milk protein synthesis, setting the demand for AA, but also manipulate cellular AA transport and even blood flow to the mammary glands, securing the supply of those needed nutrients. These transduction pathways, specifically mTORC1, sense specific AA, as well as other physiological signals, including insulin, the canonical indicator of energy status. Insulin plays a key role on mTORC1 signaling, controlling its activation, once AA have determined mTORC1 localization to the lysosomal *** on this molecular model, AA and insulin signals need to be tightly coordinated to maximize milk protein synthesis rate. The evidence in lactating dairy cows supports this model, in which insulin and glucogenic energy potentiate the effect of AA on milk protein synthesis. Incorporating the effect of specific signaling AA and the differential role of energy sources on utilization of absorbed AA for milk protein synthesis seems like

关键词： Amino acids Blood flow Insulin Mammary uptake Milk proteins mTORC1 Nitrogen efficiency Splanchnic tissues

ESCRT machinery:role of membrane repair mechanisms in escaping cell death

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Signal Transduction and Targeted Therapy 2022年第8期7卷 2655-2657页

作者： Lisa Gregor Sophia Stock sebastian Kobold Division of Clinical Pharmacology Department of Medicine IVUniversity HospitalLudwig Maximilian University(LMU)of MunichLindwurmstrasse 2a80337 MunichGermany Department of MedicineⅢ University HospitalLudwig Maximilian University(LMU)of MunichMarchioninistrasse 1581377 MunichGermany German Cancer Consortium(DKTK) Partner Site MunichPettenkoferstrasse 8a80336 MunichGermany Einheit für Klinische Pharmakologie(EKLiP) Helmholtz Zentrum MünchenGerman Research Center for Environmental Health(HMGU)Ingolstädter Landstrasse 185764 NeuherbergGermany

A recent research article published in Science by Ritter et *** that endosomal sorting complexes required for transport(ESCRT)proteins mediate repair of lesions in the cell membrane caused by the pore-forming toxin perforin at sites of cytotoxic T cell engagement.1 Subsequent entry of granzymes and initiation of apoptosis of cancer cells is thus limited,leading to reduced sensitivity against T cell‑mediated cytotoxicity.1 Along these lines,this could constitute a new critical resistance mechanism for T cellbased treatment approaches.

关键词： al. cytotoxicity death

Wear dependent virtual flow rate sensor for progressing cavity pumps with deformable stator

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Petroleum Science 2024年第2期21卷 1346-1353页

作者： Jens Müller sebastian Leonow Johannes Schulz Christian Hansen Martin Monnigmann Ruhr-Universitat Bochum Universit atsstraûe 150Bochum44801Germany SEEPEX GmbH Scharnh olzstraûe 344Bottrop46240Germany

This contribution presents a novel wear dependent virtual flow rate sensor for single stage single lobe progressing cavity pumps. We study the wear-induced material loss of the pump components and the impact of this material loss on the volumetric efficiency. The results are combined with an established backflow model to implement a backflow calculation procedure that is adaptive to wear. We use a laboratory test setup with a highly abrasive fluid and operate a pump from new to worn condition to validate our approach. The obtained measurement data show that the presented virtual sensor is capable of calculating the flow rate of a pump being subject to wear during its regular operation.

关键词： Backflow Progressing cavity pump Virtual sensor Wear

Superconvergence of a Galerkin FEM for Higher-Order Elements in Convection-Diffusion Problems

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Numerical Mathematics(Theory,Methods and Applications) 2014年第3期7卷 356-373页

作者： sebastian Franz H.-G.Roos Institut für Numerische Mathematik Technische Universit¨at Dresden01062 DresdenGermany

In this paper we present a first supercloseness analysis for higher-order Galerkin FEM applied to a singularly perturbed convection-diffusion *** a solution decomposition and a special representation of our finite element space,we are able to prove a supercloseness property of p+1/4 in the energy norm where the polynomial order p≥3 is odd.

关键词： Singular perturbation layer-adapted meshes superconvergence postprocessing

Innate immune recognition and modulation in hepatitis D virus infection

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World Journal of Gastroenterology 2020年第21期26卷 2781-2791页

作者： Stephanie Jung sebastian Maximilian Altstetter Ulrike Protzer Institute of Virology Technical University of Munich/Helmholtz Zentrum MünchenMunich D-81675Germany German Center for Infection Research(DZIF) Munich Partner SiteMunich D-81675Germany

Hepatitis D virus(HDV)is a global health threat with more than 15 million humans *** treatment options are largely unsatisfactory leaving chronically infected humans at high risk to develop liver cirrhosis and hepatocellular *** is the only human satellite virus *** encodes only two proteins,and requires Hepatitis B virus(HBV)envelope protein expression for productive virion release and spread of the *** HDV could evolve and why HBV was selected as a helper virus remains *** the discovery of Na+-taurocholate co-transporting polypeptide as the essential uptake receptor for HBV and HDV,we are beginning to understand the interactions of HDV and the immune *** HBV is mostly regarded a stealth virus,that escapes innate immune recognition,HBV-HDV coinfection is characterized by a strong innate immune *** RNA sensor melanoma differentiation antigen 5 has been reported to recognize HDV RNA replication and activate innate *** immunity,however,seems not to impair HDV replication while it inhibits *** this review,we describe what is known up-to-date about the interplay between HBV as a helper and HDV’s immune evasion strategy and identify where additional research is required.

关键词： Hepatitis D virus Hepatitis B virus Innate immunity Pathogen-associated molecular pattern molecules Immune evasion Immunosuppression

Latent HIV-1 TAR Regulates 7SK-responsive P-TEFb Target Genes and Targets Cellular Immune Responses in the Absence of Tat

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Genomics, Proteomics & Bioinformatics 2017年第5期15卷 313-323页

作者： sebastian Eilebrecht Bernd-Joachim Benecke Arndt G. Benecke CNRS UMR8246 Université Pierre et Marie Curie Paris 75005 France ACSIOMA GmbH Technologiezentrum Ruhr Bochum 44799 Germany Center for Innate Immunity and Immune Disease University of Washington School of Medicine Seattle WA 98195 USA

The transactivating response element （TAR） structure of the nascent HIV-1 transcript is critically involved in the recruitment of inactive positive transcription elongation factor b （P-TEFb） to the promoter proximal paused RNA polymerase II. The viral transactivator Tat is responsible for subsequent P-TEFb activation in order to start efficient viral transcription elongation. In the absence of the viral transactivator of transcription （Tat）, e.g., during latency or in early stages of HIV tran- scription, TAR mediates an interaction of P-TEFb with its inhibitor hexamethylene bis-aeetamide- inducible protein 1 （HEXIM1）, keeping P-TEFb in its inactive form. In this study, we address the function of HIV-1 TAR in the absence of Tat by analyzing consequences of HIV-1 TAR overexpres- sion on host cellular gene expression. An RNA chimera consisting of Epstein-Barr virus-expressed RNA 2 （EBER2） and HIV-1 TAR was developed to assure robust overexpression of TAR in HEK293 cells. The overexpression results in differential expression of more than 800 human genes. A significant proportion of these genes is involved in the suppression of cellular immune responses, including a significant set of 7SK-responsive P-TEFb target genes. Our findings identify a novel role for HIV-1 TAR in the absence of Tat, involving the interference with host cellular immune responses by targeting 7SK RNA-mediated gene expression and P-TEFb inactivation.

关键词： HIV-1 Latency TAR 7SK RNA Cellular immunity