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Journal of Integrative Plant Biology 2013年第9期55卷 864-875页

作者： christian lfke Kai Dünser Jürgen Kleine‐Vehn Department of Applied Genetics and Cell Biology Vienna Institute of Biotechnology (VIBT) University of Natural Resources and Life Sciences Vienna (BOKU)Muthgasse 18 1190 Vienna Austria

The regulation of cellular growth is of vital importance for embryonic and postembryonic patterning. Growth regulation in the epidermis has importance for organ growth rates in roots and shoots, proposing epidermal cells as an interesting model for cellular growth regulation. Here we assessed whether the root epidermis is a suitable model system to address cell size determination. In Arabidopsis thaliana l., root epidermal cells are regularly spaced in neighbouring tricho-（root hair） and atrichoblast （non-hair） cells, showing already distinct cell size regulation in the root meristem. We determined cell sizes in the root meristem and at the onset of cellular elongation, revealing that not only division rates but also cellular shape is distinct in tricho-and atrichoblasts. Intriguingly, epidermal-patterning mutants, failing to define differential vacuolization in neighbouring epidermal cell files, also display non-differential growth. Using these epidermal-patterning mutants, we show that polarized growth behaviour of epidermal tricho-and atrichoblast is interdependent, suggesting non-cell autonomous signals to integrate tissue expansion. Besides the interweaved cell-type-dependent growth mechanism, we reveal an additional role for epidermal patterning genes in root meristem size and organ growth regulation. We conclude that epidermal cells represent a suitable model system to study cell size determination and interdependent tissue growth.

关键词： Atrichobtast cell size determination trichoblast,

Experimental and numerical investigation to elucidate the fluid flow through packed beds with structured particle packings

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Particuology 2024年第6期89卷 218-237页

作者： Shirin Patil christian Gorges Joel lòpez Bonilla Moritz Stelter Frank Beyrau Berend van Wachem laboratory of Technical Thermodynamics Otto-von-Guericke-Universität MagdeburgUniversitätsplatz 239106 MagdeburgGermany Chair of Mechanical Process Engineering Otto-von-Guericke-Universität MagdeburgUniversitätsplatz 239106 MagdeburgGermany

The present paper presents an experimental and numerical investigation of the dispersion of the gaseous jet flow and co-flow for the simple unit cell(SUC)and body-centred cubic(BCC)configuration of particles in packed *** experimental setup is built in such a way that suitable and simplified boundary conditions are imposed for the corresponding numerical framework,so the simulations can be done under very similar conditions as the ***,a porous plate is used for the co-flow to achieve the uniform velocity and the fully developed flow is ensured for the jet *** SUC and BCC particle beds consist of 3D-printed spheres,and the non-isotropy near the walls is mostly eliminated by placing half-spheres at the channel *** flow velocities are analysed directly at the exit of the particle bed for both beds over 36 pores for the SUC configuration and 60 pores for the BCC configuration,for particle Reynolds numbers of 200,300,and *** particle image velocimetry is experimentally arranged in such a way that the velocities over the entire region at the exit of the packed bed are obtained *** numerical method consists of a state-of-the-art immersed boundary method with adaptive mesh *** paper presents the pore jet structure and velocity field exiting from each pore for the SUC and BCC packed particle *** numerical and experimental studies show a good agreement for the SUC configuration for all flow *** the BCC configuration,some differences can be observed in the pore jet flow structure between the simulations and the experiments,but the general flow velocity distribution shows a good overall *** axial velocity is generally higher for the pores located near the centre of the packed bed than for the pores near the *** addition,the axial velocities are observed to increase near the peripheral pores of the packed *** behaviour is predominant for the BCC configuration as compared to t

关键词： Uniform particle packing Packed bed reactor Stereo particle image velocimetry Immersed boundary method

Adsorption of pharmaceutical pollutants on ZnCl_(2)-activated biochar from corn cob:Efficiency,selectivity and mechanism

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Journal of Bioresources and Bioproducts 2024年第1期9卷 58-73页

作者： christian F.Varela l.C.Moreno-Aldana Yazmin Yaneth Agámez-Pertuz Department of Chemistry National University of ColombiaAv.Carrera 30 No.45-03BogotáD.C.Colombia Department of Biology and Chemistry University of the Llanoskm 12 road to Puerto LópezVillavicencioColombia

The occurrence of pharmaceuticals in water bodies and drinking water poses risks for the envi-ronment and human health,thus it is necessary to study methodologies that allow the efficient removal of these *** this work,corn cob-derived biochar was obtained by ZnCl_(2)-activation,and subsequent carbonization at 700℃.The effect of contact time,temperature,pH,and initial concentration on the adsorption capacity of acetaminophen(ACE)and amoxicillin(AMX)was determined through batch *** addition,the kinetics,isotherms,and ther-modynamics parameters were *** activated biochar exhibited a maximum adsorp-tion capacity of 332.08 mg/g for ACE and 175.86 mg/g for *** adsorption kinetics and adsorption isotherm of ACE corresponded to the pseudo-second order and langmuir model,***,pseudo-first-order kinetics and the Freundlich isotherm model were well-fitted to AMX *** ACE and AMX co-adsorption had a synergistic effect on AMX but an antagonistic effect on ACE removal,achieving a maximum adsorption capacity of 193.51 and 184.58 mg/g,*** the other hand,fixed-bed column experiments showed that the adsorption capacity depends on the influent concentration,and the breakthrough curve fits the Thomas and Yoon-Nelson *** mechanism adsorption studies showed that surface inter-actions(hydrogen bonding formation and n-𝜋interactions)are the main driving forces for the adsorption process,and pore filling is the rate-limiting *** this way,the prepared biochar exhibits a high potential for the adsorption of pharmaceutical compounds from water.

关键词： Biochar Adsorption Acetaminophen Amoxicillin Wastewater treatment

Gust response of an elasto-flexible morphing wing using fluid–structure interaction simulations

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Chinese Journal of Aeronautics 2024年第2期37卷 45-57页

作者： Jonathan PFlÜGER christian BREITSAMTER Department of Mechanical Engineering Technical University of MunichGarching 85748Germany

Small and micro unmanned aircraft are the focus of scientific interest due to their wide range of *** often operate in a highly unstable flight environment where the application of new morphing wing technologies offers the opportunity to improve flight *** investigated concept comprises port and starboard adjustable wings,and an adaptive elastoflexible membrane serves as the lifting *** focus is on the benefits of the deforming membrane during the impact of a one-minus-cosine type *** a low Reynolds number of Re=264000,the morphing wing model is investigated numerically by unsteady fluid-structure interaction ***,the numerical results are validated by experimental data from force and moment,flow field,and deformation ***,with the rigid wing as the baseline,the flexible case is investigated,focusing on the advantages of the elastic *** all configurations studied,the maximum amplitude of the lift coefficient under gust load shows good agreement between the experimental and numerical *** the decay of the gust,they differ more the higher the aspect ratio of the *** considering the flow field,the main differences are due to the separation behavior on the upper side of the *** flow reattaches earlier in the experiments than in the simulations,which explains the higher lift values observed in the *** at one intermediate configuration does the lift amplitude of the rigid configuration exceeds that of the flexible by about 12%,with the elastic membrane resulting in a smaller and more uniform peak load,which is also evident in the wing loading and hence in the root bending moment.

关键词： Membrane wing Morphing wing Flexible wing surface Computational fluid dynam-ics Fluid-structure interaction Unsteady inflow condition Gust response

Aggresome-aggrephagy transition process:geting closer to the functional roles of HDAC6 and BAG3

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Neural Regeneration Research 2024年第6期19卷 1181-1182页

作者： Hagen Körschgen christian Behl The Autophagy lab Institute of PathobiochemistryUniversity Medical Center of the Johannes Gutenberg University MainzMainzGermany

Misfolding of proteins as well as their aggregation is a major driver of age-related neurodegenerative ***,cells have evolved sophisticated protein quality control *** the ubiquitin-proteasome-system(UPS)and the autop... 详细信息

关键词： closer system transition

Ray tracing particle image velocimetry-Challenges in the application to a packed bed

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Particuology 2024年第1期84卷 194-208页

作者： Christin Velten Mirko Ebert christian lessig Katharina Zahringer lehrstuhl für Strömungsmechanik und Strömungstechnik Otto-von-Guericke-Universität Magdeburg39106MagdeburgGermany Institut für Simulation und Graphik Otto-von-Guericke-Universität Magdeburg39106MagdeburgGermany

Ray tracing Particle Image Velocimetry(RT-PIV)is an optical technique for high resolution velocity measurements in challenging optical systems,such as transparent packed beds,that uses ray tracing to correct for distortions introduced by transparent geometries in the light *** ray tracing based correction is a post processing step applied to the raw PIV particle images before classical PIV *** this study,RT-PIV is performed in the top layer of a body centred cubic(bcc)sphere packing with gaseous flow,where optical access is obtained by the use of transparent N-BK7 glass balls with a diameter of d=40 ***-PIV introduces new experimental and numerical challenges,for example a limited field of view,illumination difficulties,a very large required depth of field and high sensitivity to geometric parameters used in the ray tracing *** challenges and their implications are the main scope and discussed in the present ***,the validation of the ray tracing reconstruction step is presented and examples for the obtained corrected vector fields in a packed bed are *** results show the strength of the method in reconstructing velocity fields behind transparent spheres that would not have been accessible by optical measurement techniques without the ray tracing correction.

关键词： Ray tracing particle image velocimetry(RT-PIV) Transparent spherical particles Packed bed Distortion correction Gas flow

Diabetes and pulmonary infection:how hyperglycaemia shapes the immune system

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Signal Transduction and Targeted Therapy 2024年第4期9卷 1245-1246页

作者： christian Herder Michael Roden Nicolas Venteclef Institute for Clinical Diabetology German Diabetes CenterLeibniz Center for Diabetes Research at Heinrich Heine University Düsseldorf40225DüsseldorfGermany German Center for Diabetes Research(DZD) Partner Düsseldorf85764München-NeuherbergGermany Department of Endocrinology and Diabetology Medical Faculty and University Hospital DüsseldorfHeinrich Heine University Düsseldorf40225DüsseldorfGermany Institut Necker-Enfants Malades(INEM) UniversitéParis CitéINSERM UMR-S1151CNRS UMR-S8253ParisFrance

In a recent study published in Nature,Nobs and colleagues aimed to identify novel mechanisms that may explain why diabetes is associated with an increased susceptibility to viral respiratory *** analyses revealed a central role of lung dendritic cells(DC)which exhibited several functional defects induced by hyperglycaemia and consequently result in impaired antiviral immune responses.

关键词： impaired lung respiratory

Clustering of voltage-gated ion channels as an evolutionary trigger of myelin formation

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Neural Regeneration Research 2024年第8期19卷 1631-1632页

作者： Henrike Ohm Simone Rey christian Klambt Institut fur Neuro-und Verhaltensbiologie MunsterGermany

Neurons carry apical dendrites that perceive information and a basal axon that transmits the computed information towards its to *** axon originates at the axon hillock which is followed by the axon initial ***,action potentials are initiated that are based on millisecond long openings of specific voltagegated sodium and potassium channels that are conserved in all parahoxozoa(Placozoa,Cnidaria,Bilateria)(li et al.,2015).

关键词： initiated carry potassium

Prosaposin hyperglycosylation: a novel tumor immune escape mechanism and implications for cancer immunotherapy

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Signal Transduction and Targeted Therapy 2024年第8期9卷 3150-3152页

作者： Matthias Peipp Diana Dudziak christian Kellner Division of Antibody-Based Immunotherapy Department of Medicine IChristian-Albrechts University and University Hospital Schleswig-HolsteinKielGermany institute of Immunology Jena University HospitalFriedrich-Schiller-UniversityJenaGermany Comprehensive Cancer Center Central Germany Jena/leipzig JenaGermany Division of Transfusion Medicine Cell Therapeutics and HaemostaseologyLMU University HospitalLMU MunichMunichGermany

In a recent article published in Science,Sharma et *** the essential role of saposins in cross-presentation of tumor membraneassociated antigens by dendritic cells(DC)to CD8^(+)T cells.1 However,antigen cross-presentation,which is fundamental in cancer cell elimination,is hindered in tumor DC by hyperglycosylation of the common saposin precursor prosaposin(pSAP)leading to impaired T cell tumor immunity-yet,the potential of recombinant pSAP to re-establish T cell responses may offer a novel way to counteract immune evasion in a therapeutic approach.

关键词： impaired immunity al.

A numerical and experimental comparison of heat transfer in a quasi two-dimensional packed bed

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Particuology 2024年第1期84卷 136-144页

作者： Matthias Tyslik Mirko Ebert Martin Schiemann Siegmar Wirtz christian lessig Department of Energy Plant Technology Ruhr-University BochumGermany Institute for Simulation and Graphics Otto-von-Guericke-Universität MagdeburgGermany

Heat transfer plays a major role in many industrial processes taking place in packed *** accurate and reliable simulation of the heat exchange between particles is therefore crucial for a reliable operation and to optimize the processes in the *** discrete ordinates method(DOM)provides an established numerical technique to model radiative heat transfer in granular media that offers the possibility to consider the directional dependence of the radiation *** this work,DOM is compared with Monte Carlo ray tracing,which provides an alternative method for heat transfer ***-rically simple configurations are used to investigate the influence of the angular discretization on the accuracy of the results and the computation time in both *** obtained insights are then transferred to a more complex configuration of a quasi two-dimensional test rig consisting of metal rods for which also experimental results are *** results show that both DOM and Monte Carlo ray tracing allow for an accurate simulation of heat transfer in packed *** Carlo ray tracing requires thereby computation times that are surprisingly competitive(although still somewhat slower)compared to DOM and allows for an easier computation of highly accurate reference *** our preliminary comparison to the experimental test rig,Monte Carlo ray tracing also provides the advantage that it can more easily model highly specular materials such as stainless *** methods are comparable for diffuse materials such as magnesium oxide.

关键词： Heat transfer Discrete ordinates method Monte Carlo ray tracing