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GEVREY CLASS REGULARITY FOR THE GLOBAL ATTRACTOR OF A TWO-DIMENSIONAL NON-NEWTONIAN FLUID

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Acta Mathematica Scientia 2022年第1期42卷 265-282页

作者：赵才地林泽瀚 T.achim MEDJO Department of Mathematics Wenzhou UniversityWenzhou 325035China Department of Mathematics Florida International UniversityBM413B University ParkMiamiFL 33199USA

This article investigates Gevrey class regularity for the global attractor of an incompressible non-Newtonian fluid in a two-dimensional domain with a periodic boundary *** Gevrey class regularity reveals that the solutions lying in the global attractor are analytic in time with values in a Gevrey class of analytic functions in space.

关键词： non-Newtonian fluid global attractor Gevrey class regularity

Proteome-Based Clustering Approaches Reveal Phylogenetic Insights into Amphistegina

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Journal of Earth Science 2022年第6期33卷 1469-1479页

作者： Marleen Stuhr Bernhard Blank-Landeshammer achim Meyer Vera Baumeister Jörg Rahnenführer Albert Sickmann Hildegard Westphal Leibniz Centre for Tropical Marine Research(ZMT) BremenGermany Leibniz-Institut für Analytische Wissenschaften-ISAS-e.V. DortmundGermany Austrian Competence Center for Feed and Food Quality Safety and InnovationWelsAustria Chrestos Concept GmbH&Co KG EssenGermany Department of Statistics TU Dortmund UniversityDortmundGermany Medizinisches Proteom-Center(MPC) Ruhr-Universität BochumBochumGermany Department of Chemistry University of AberdeenOld AberdeenScotlandUK Department of Geosciences Bremen UniversityBremenGermany King Abdullah University of Science and Technology(KAUST) ThuwalSaudi Arabia

Foraminifera are highly diverse and have a long evolutionary *** key bioindicators,their phylogenetic schemes are of great importance for paleogeographic applications,but may be hard to recognize *** phylogenetic relationships within the prominent genus Amphistegina are still *** studies on Amphistegina have so far only focused on genetic diversity within single species and suggested a cryptic diversity that demands for further *** molecular sequencing-based approaches,different mass spectrometry-based proteomics approaches are increasingly used to give insights into the relationship between samples and organisms,especially as these do not require reference *** better understand the relationship of amphisteginids and test different proteomics-based approaches we applied de novo peptide sequencing and similarity clustering to several populations of Amphistegina lobifera,*** and *** also analyzed the dominant photosymbiont community to study their influence on holobiont *** analyses indicate that especially de novo peptide sequencing allows to reconstruct the relationship among foraminiferal holobionts,although the detected separation of *** from *** and *** may be partly influenced by their different photosymbiont *** resulting dendrograms reflect the separation in two lineages previously suggested and provide a basis for future studies.

关键词： large benthic foraminifera de novo peptide sequencing tandem mass spectra clustering LC-MS/MS runs proteomics symbiont diversity phylogeography Fragilariales

Minimally invasive surgery for gastro-oesophageal junction adenocarcinoma: Current evidence and future perspectives

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World Journal of Gastrointestinal Oncology 2023年第10期15卷 1675-1690页

作者： Rodica Birla Petre Hoara Florin achim Valeriu Dinca Diana Ciuc Silviu Constantinoiu Adrian Constantin Department of General Surgery Carol Davila UniversityBucharest 011172Romania Department of General Surgery Carol Davila University of Medicine and PharmacyBucharest 020021Romania Faculty of Medicine “Titu Maiorescu”UniversityBucharest 031593Romania

Minimally invasive surgery is increasingly indicated in the management of malignant *** oesophagectomy is a difficult operation,with a long learning curve,there is actually a shift towards the laparoscopic/thoracoscopic/robotic approach,due to the advantages of visualization,surgeon comfort(robotic surgery)and the possibility of the whole team to see the operation as well as and the operating *** currently there are still many controversial topics,about the surgical treatment of patients with gastro-oesophageal junction(GOJ)adenocarcinoma,such as the type of open or minimally invasive surgical approach,the type of oesophago-gastric resection,the type of lymph node dissection and others,the minimally invasive approach has proven to be a way to reduce postoperative complications of resection,especially by decreasing pulmonary *** implementation of new technologies allowed the widening of the range of indications for this type of surgical *** short-term and long-term results,as well as the benefits for the patient-reduced surgical trauma,quick and easy recovery-offer this type of surgical treatment the premises for future *** article reviews the updates and perspectives on the minimally invasive approach for GOJ adenocarcinoma.

关键词： Gastro-oesophageal adenocarcinoma Minimally invasive oesophagectomy Laparoscopic gastrectomy Abdomino-mediastinal lymph node dissection Indocyanine green fluorescence imaging

A high-order full-discretization method using Hermite interpolation for periodic time-delayed differential equations

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Acta Mechanica Sinica 2015年第3期31卷 406-415页

作者： Yilong Liu achim Fischer Peter Eberhard Baohai Wu Key Laboratory of Contemporary Design and Integrated Manufacturing Technology Northwestern Polytechnical University Institute of Engineering and Computational Mechanics University of Stuttgart

A high-order full-discretization method （FDM） using Hermite interpolation （HFDM） is proposed and implemented for periodic systems with time delay. Both Lagrange interpolation and Hermite interpolation are used to approximate state values and delayed state values in each discretization step. The transition matrix over a single period is determined and used for stability analysis. The proposed method increases the approximation order of the semidiscretization method and the FDM without increasing the computational time. The convergence, precision, and efficiency of the proposed method are investigated using several Mathieu equations and a complex turning model as examples. Comparison shows that the proposed HFDM converges faster and uses less computational time than existing methods.

关键词： Full-discretization method Time delay -Stability Chatter

Stability analysis of a thin-walled cylinder in turning operation using the semi-discretization method

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Acta Mechanica Sinica 2014年第2期30卷 214-222页

作者： Arnab Chanda achim Fischer Peter Eberhard Santosha Kumar Dwivedy Institute of Engineering and Computational Mechanics University of Stuttgart

In this work, the stability of a flexible thin cylindrical workpiece in turning is analyzed. A process model is derived based on a finite element representation of the workpiece flexibility and a nonlinear cutting force law. Repeated cutting of the same surface due to overlapping cuts is modeled with the help of a time delay. The stability of the so obtained system of periodic delay differential equations is then determined using an approximation as a time-discrete system and Floquet theory. The time-discrete system is obtained using the semi-discretization method. The method is implemented to analyze the stability of two different workpiece models of different thicknesses for different tool positions with respect to the jaw end. It is shown that the stability chart depends on the tool position as well as on the thickness.

关键词： Machine tools Stability Chatter

Sustainable intensification of agriculture in sub-Saharan Africa:first things first!

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Frontiers of Agricultural Science and Engineering 2020年第4期7卷 376-382页

作者： Bernard VANLAUWE achim DOBERMANN International Institute of Tropical Agriculture Nairobi00100 NairobiKenya 2 International Fertilizer Association75116 ParisFrance

We both belong to a generation of soils scientists and agronomists who have spent or are spending their career trying to develop and scale better soil and crop management solutions for smallholder farmers in the *** have witnessed some successes in this,but also many ***,the work of the first author(BV)has primarily been in sub-Saharan Africa(SSA),while much of the work of the second author(AD)has been in *** both believe that there is great urgency to accelerate crop production in Africa,the region with the greatest challenges for food and nutritional security and socioeconomic *** believe that what SSA needs most now is an agronomic revolution.

关键词： soil Sustainable Africa

Improving the dynamic stability of a workpiece dominated turning process using an adaptronic tool holder

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Theoretical & Applied Mechanics Letters 2013年第1期3卷 63-70页

作者： achim Fischer Peter Eberhard Institute of Engineering and Computational Mechanics University of Stuttgart

In this contribution, inside turning of a thin-walled cylinder is investigated in simulation. Self-excited vibrations can arise due to repeated cutting of the same surface, that lead to instability.A flexible multibody system model of the system is the basis for a subsequent analysis of the stability of the process. Stability analysis is done using an approximation as a time-discrete system via the semi-discretization method. An adaptronic turning chisel comprising a piezo actuator and sensors is then used in combination with different control concepts to improve the stability of the process. The effectiveness of the different strategies is compared based on the influence on the stability charts. A classic H∞ controller based on a model of the coupled system of workpiece and tool can only yield some improvements, when an additional measurement of the workpiece displacement is added. Incorporating knowledge on the cutting process coupling workpiece and tool using a gain scheduled H∞ controller allows further improvements. However, robustness with respect to model uncertainties, notably concerning the force law, remains an issue. C 2013 The Chinese Society of Theoretical and Applie-d Mechanics. [doi：10.1063/2.1301308]

关键词： multibody dynamics vibrations stability feedback control

Li2SnO3 branched nano- and microstructures with intense and broadband white-light emission

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Nano Research 2019年第2期12卷 441-448页

作者： Miguel Garcia-Tecedor Javier Bartolome David Maestre achim Trampert Ana Cremades Dpt. Fisica de Materials Facultad de CC. Fisicas Universidad Complutense de Madrid Madrid 28040 Spain Paul-Drude-Institut fur Festkorperelektronik Hausvogteiplatz 5-7 Berlin 10117 Germany Institute of Advanced Materials (INAM) Universitat Jaume I Castello 12006 Spain Dpt. Fisica de Materiales Facultad de CC. Ftsicas Universidad Complutense de Madrid Madrid 28040 Spain

Exploiting the synergy between microstructure, morphology and dimensions by suitable nanomaterial engineeri ng, can effectively upgrade the physical properties and material performances. Li2SnO3 elongated nano- and microstructures in form of belts, wires, rods and branched structures have been fabricated by a vapor-solid method at temperatures ranging from 700 to 900℃ using metallic Sn and Li2CO3 as precursors. The achievement of these new morphologies can face challenging applications for Li2SnO3, not only in the field of energy storage, but also as building blocks in optoelectronic devices. The micro? and nanostructures grown at 700 and 800℃ correspond to monoclinic Li2SnO3, while at 900℃ complex Li2S nO/SnO2 core-shell microstructures are grow n, as con firmed by X-ray diffractio n and Rama n spectroscopy. Transmission electron microscopy reveals structural disorder related to stacking faults in some of the branched structures, which is associated with the prese nee of the low-temperature phase of L12S nO3. The luminescent resp onse of these structures is domi nated by in tense emissi ons at 2, 2.5 and 3 eV, almost completely covering the whole range of the visible light spectrum. As a result, white-light emission is obtained without the need of phosphors or complex quantum well heterostructures. Enhanced functionality in applications such as in light-emitting devices could be exploited based on the high luminescenee intensity observed in some of the analysed Li2SnO3 structures.

关键词： lithium oxides white light emitters nanostructures luminescenee

The Root Cap Determines Ethylene-Dependent Growth and Development in Maize Roots

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Molecular Plant 2008年第2期1卷 359-367页

作者： achim Hahn Roman Zimmermann Dierk Wanke Klaus Harter Hans G. Edelmann Botanisches Institut Universitfit zu Koin Gyrhofstr. 15 D-50931 Koin Germany Present address: ZMBP Pflanzenphysiologie University TQbingen Auf der Morgenstelle 1 D-72076 TQbingen Germany Institut fur Entwicklungsbiologie Universitat zu Koin Gyrhofstr. 17 D-50931 Koin Germany Institut fur Entwicklungsbiologie Universitat zu Koin Gyrhofstr. 17 D-50931 Koln Germany ZMBP Pflanzenphysiologie Universitat Tubingen Auf der Morgenstelle 1 D-72076 Tubingen Germany Present address: Biologie und ihre Didaktik Universitat Siegen D-57068 Siegen Germany

Besides providing protection against mechanical damage to the root tip, the root cap is involved in the perception and processing of diverse external and internal stimuli resulting in altered growth and development, The transduction of these stimuli includes hormonal signaling pathways such as those of auxin, ethylene and cytokinin. Here, we show that the root cap is essential for the ethylene-induced regulation of elongation growth and root hair formation in maize. Exogenously applied ethylene is no longer able to inhibit elongation growth when the root cap has been surgically removed prior to hormone treatment. Reconstitution of the cap positively correlates with the developing capacity of the roots to respond to ethylene again. In contrast, the removal of the root cap does not per se affect growth inhibition controlled by auxin and cytokinin. Furthermore, our semi-quantitative RT-PCR results support earlier findings that the maize root cap is a site of high gene expression activity with respect to sensing and responding to hormones such as ethylene, From these data, we propose a novel function of the root cap which is the establishment of competence to respond to ethylene in the distal zones of the root.

关键词： AUXIN BIOSYNTHESIS INSENSITIVE MUTANTS CELL ELONGATION