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miniSCIdOM: a scintillator-based tomograph for volumetric dose reconstruction of single laser-driven proton bunches

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High Power Laser Science and Engineering 2024年第2期12卷 41-50页

作者： A.Corvino M.Reimold E.Beyreuther F.-E.Brack F.Kroll J.Pawelke J.d.Schilz M.Schneider U.Schramm M.E.P.Umlandt K.Zeil T.Ziegler J.Metzkes-Ng Helmholtz-Zentrum dresden–Rossendorf DresdenGermany Technische Universität dresden DresdenGermany OncoRay–National Center for Radiation Research in Oncology Faculty of Medicine and University Hospital Carl Gustav CarusTUD Dresden University of TechnologyHelmholtz-Zentrum Dresden–RossendorfDresdenGermany Current affiliation:Institut Curie UniversitéPSLCNRS UMR3347OrsayFrance Current affiliation:Universitätsklinikum freiburg FreiburgGermany

Laser plasma accelerators(LPAs)enable the generation of intense and short proton bunches on a micrometre scale,thus offering new experimental capabilities to research fields such as ultra-high dose rate radiobiology or material *** spectrally broadband,laser-accelerated proton bunches allow for tailored volumetric dose deposition in a sample via single bunches to excite or probe specific sample *** rising number of such experiments indicates a need for diagnostics providing spatially resolved characterization of dose distributions with volumes of approximately 1 cm^(3) for single proton bunches to allow for fast online *** we present the scintillator-based miniSCIdOM detector for online single-bunch tomographic reconstruction of dose distributions in volumes of up to approximately 1 cm^(3).The detector achieves a spatial resolution below 500μm and a sensitivity of 100 *** detector performance is tested at a proton therapy cyclotron and an LPA proton *** experiments’primary focus is the characterization of the scintillator’s ionization quenching behaviour.

关键词： beam monitoring detectors laser-driven proton beams scintillator-based diagnostics ultra-high dose rate

dICER-LIKE3 Activity in Physcomitrella patens dICER-LIKE4 Mutants Causes Severe developmental dysfunction and Sterility

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Molecular Plant 2012年第6期5卷 1281-1294页

作者： M. Asif Arif Isam Fattash Zhaorong Ma Sung Hyun Cho Anna K. Beike Ralf Reski Michael J. Axtell Wolfgang Frank Plant Biotechnology Faculty of Biology University of Freiburg Schaenzlestral3e 1 D-79104 Freiburg Germany department of Biology Pennsylvania State University University Park PA 16802 USA FRISYs freiburg Initiative for Systems Biology D-79104 Freiburg: Germany BIOSS Centre for Biological Signalling Studies D-79104 Freiburg Germany FRIAS freiburg Institute for Advanced Studies D-79104 Freiburg Germany

Trans-acting small interfering RNAs （ta-siRNAs） are plant-specific siRNAs released from TAS precursor tran- scripts after microRNA-dependent cleavage, conversion into double-stranded RNA, and dicer-dependent phased process- ing. Like microRNAs （miRNAs）, ta-siRNAs direct site-specific cleavage of target RNAs at sites of extensive complementarity. Here, we show that the dICER-LIKE 4 protein of Physcomitrella patens （PpdCL4） is essential for the biogenesis of 21 nucleotide （nt） ta-siRNAs. In APpdCL4 mutants, off-sized 23 and 24-nt ta-siRNAs accumulated as the result of PpdCL3 activity. APpdCL4 mutants display severe abnormalities throughout Physcomitrella development, including sterility, that were fully reversed in APpdCL3/APpdCL4 double-mutant plants. Therefore, PpdCL3 activity, not loss of PpdCL4 function per se, is the cause of the APpdCL4 phenotypes. Additionally, we describe several new Physcomitrella trans-acting siRNA loci, three of which belong to a new family, TA56. TAS6 loci are typified by sliced miR156 and miR529 target sites and are in close proximity to PpTAS3 loci.

关键词： ta-siRNA miR156 PpdCL3 PpdCL4 development moss.

Speciation in nanosecond laser ablation of zinc in water

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Science China(Physics,Mechanics & Astronomy) 2022年第7期65卷 90-98页

作者： Stefan Reich Yannis Klügl Anna Ziefuss RenéStreubel Jorg Gottlicher Anton Plech Institute for Photon Science and Synchrotron Radiation Karlsruhe Institute of TechnologyKarlsruhe D-76021Germany department of Technical ChemistryⅠand Center for Nanointegration duisburg-Essen University of Duisburg-EssenEssen D-45141Germany Fraunhofer Institute for High-Speed dynamics Ernst-Mach-Institute(EMI)Freiburg 79104Germany

In situ experimental methods have been applied to resolve mass flow and chemical speciation in the pulsed laser ablation of zinc in water. The chemical speciation has been resolved by time-resolved μ-X-ray absorption spectroscopy and mapped onto the macroscopic mass flow during material ejection from the metallic target and bubble dynamics of evaporated water. Large particles and agglomerates have been detected via dark-field X-ray imaging with a Shack-Hartmann sensor. The characteristic of the dynamics is that the vapor bubble is nearly homogeneously filled with ablated material. This persists during bubble collapse,which means that the ablated particles are captured and retracted towards the target. Limited mass escape is indicated by the X-ray absorption signal. Importantly, the near-edge structure at the Zn-K;transition delivers information on the chemical state of the ejected material. It clearly confirms that oxidation is not present within the bubble phase and the following sub-millisecond time scale. The oxidation proceeds on Zn nanoparticles in suspension on a second to minute course. Within the first microseconds,a Zn atom phase is detected that resembles Zn vapor. The addition of either reductive NaBH;or oxidative HAuCl;to the water phase influences the quantity of the atom contribution moderately, but does not influence the initial atom phase. Such behavior must be understood in terms of the nanosecond pulse excitation. After ejected material and a plasma is formed within the pulse duration of 7 ns the laser is able to further heat the ejecta and transform it partly into vapor. Correspondingly, the coupling of energy into the ablation zone as followed by plasma intensity and bubble size follows a threshold behavior as a function of laser fluence, marking the onset of laser-plasma heating. The reaction conditions inside the bubble are probably reductive due to the concomitant formation of excess hydrogen.

关键词： laser ablation in liquids elemental speciation X-ray absorption spectroscopy oxidation zinc oxide nanoparticles

Towards Second Green Revolution: Engineering Nitrogen Use Efficiency

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Journal of Genetics and Genomics 2014年第6期41卷 315-316页

作者： Klaus Palme Xugang Li William d.Teale Institute of Biology II/Botany Faculty of Biology Albert-Ludwigs-University of Freiburg Schanzlestrasse 1 D-79104 Freiburg Germany Centre of Biological Systems Analysis Albert-Ludwigs-University of Freiburg Habsburgerstr. 49 D-79104 Freiburg Germany freiburg Institute of Advanced Sciences (FRIAS) Albert-Ludwigs-University of Freiburg Albertstrasse 19 D-79104 Freiburg Germany Centre for Biological Signalling Studies (BIOSS) Albert-Ludwigs-University of Freiburg Schanzlestrasse 19D-79104 Freiburg Germany

Gaseous nitrogen （N2） makes up 78% of the earth＇s at- mosphere; its incorporation into a wide range of biological macromolecules molecules, such as nucleic acids and amino acids, makes it an essential part of all life on earth. However, as nitrogen gas is inert, it remains unavailable to most organisms, including plants. Thus, in order to be useful for fertilizer production, gaseous nitrogen needs first to be converted into bioavailable organic nitrogen in processes which are inefficient and rate-limiting for agricultural pro- duction. It was not until about 100 years ago that BASF were able to produce synthetic ammonia, the main ingredient for fertilizer production, on an industrial scale from pressurized air using the Haber--Bosch process. This chemical process was not only an impressive technical feat that helped Haber （1918） and Bosch （1931） earn Nobel Prizes but also enabled farmers to achieve the high yields that drive modern agriculture.

关键词： NUE Towards Second Green Revolution Engineering Nitrogen Use Efficiency RGA

Wear-resistant CoCrNi multi-principal element alloy at cryogenic temperature

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Science Bulletin 2024年第2期69卷 227-236页

作者： Yue Ren Qing Zhou dongpeng Hua Zhuobin Huang Yulong Li Qian Jia Peter Gumbsch Christian Greiner Haifeng Wang Weimin Liu State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsNorthwestern Polytechnical UniversityXi’an 710072China Institute for Applied Materials Karlsruhe Institute of TechnologyKarlsruhe 76131Germany IAM-ZM MicroTribology CenterμTC Karlsruhe Institute of TechnologyKarlsruhe 76131Germany Fraunhofer IWM Freiburg 79108Germany State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

Traditional high strength engineering alloys suffer from serious surface brittleness and inferior wear performance when servicing under sliding contact at cryogenic ***,we report that the recently emerging CoCrNi multi-principal element alloy defies this trend and presents dramatically enhanced wear resistance when temperature decreases from 273 to 153 K,surpassing those of cryogenic austenitic *** temperature-dependent structure characteristics and deformation mechanisms influencing the cryogenic wear resistance of CoCrNi are clarified through microscopic observation and atomistic *** is found that sliding-induced subsurface structures show distinct scenarios at different deformation *** cryogenic condition,significant grain refinement and a deep plastic zone give rise to an extended microstructural gradient below the surface,which can accommodate massive sliding deformation,in direct contrast to the strain localization and delamination at 273 ***,the temperature-dependent cryogenic deformation mechanisms(stacking fault networks and phase transformation)also provide additional strengthening and toughening of the subsurface *** features make the CoCrNi alloy particularly wear resistant at cryogenic conditions and an excellent candidate for safety–critical applications.

关键词： Multi-principal element alloy Cryogenic temperature Wear CoCrNi

A flexible protruding microelectrode array for neural interfacing in bioelectronic medicine

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Microsystems & Nanoengineering 2022年第6期8卷 165-179页

作者： Helen Steins Michael Mierzejewski Lisa Brauns Angelika Stumpf Alina Kohler Gerhard Heusel Andrea Corna Thoralf Herrmann Peter d.Jones Günther Zeck Rene von Metzen Thomas Stieglitz NMI Natural and Medical Sciences Institute at the University of Tübingen ReutlingenGermany Laboratory for Biomedical Microtechnology Department of Microsystems EngineeringUniversity of FreiburgFreiburgGermany Institute of Biomedical Electronics TU WienViennaAustria Bernstein Center freiburg University of FreiburgFreiburgGermany BrainLinks-BrainTools University of FreiburgFreiburgGermany

Recording neural signals from delicate autonomic nerves is a challenging task that requires the development of a lowinvasive neural interface with highly selective,micrometer-sized *** paper reports on the development of a three-dimensional(3d)protruding thin-film microelectrode array(MEA),which is intended to be used for recording low-amplitude neural signals from pelvic nervous structures by penetrating the nerves transversely to reduce the distance to the *** gold pillars(O 20 or 50μm,~60μm height)were fabricated on a micromachined polyimide substrate in an electroplating *** sidewalls were insulated with parylene C,and their tips were optionally modified by wet etching and/or the application of a titanium nitride(TiN)*** microelectrodes modified by these combined techniques exhibited low impedances(~7 kΩ at 1 kHz for ∅ 50μm microelectrode with the exposed surface area of~5000μm^(2))and low intrinsic noise *** functionalities were evaluated in an ex vivo pilot study with mouse retinae,in which spontaneous neuronal spikes were recorded with amplitudes of up to 66μ*** novel process strategy for fabricating flexible,3d neural interfaces with low-impedance microelectrodes has the potential to selectively record neural signals from not only delicate structures such as retinal cells but also autonomic nerves with improved signal quality to study neural circuits and develop stimulation strategies in bioelectronic medicine,e.g.,for the control of vital digestive functions.

关键词： neural microelectrode electronic

Non-linear affine processes with jumps

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Probability, Uncertainty and Quantitative Risk 2023年第2期8卷 235-266页

作者： Francesca Biagini Georg Bollweg Katharina Oberpriller Workgroup Financial and Insurance Mathematics Department of MathematicsLudwig-Maximilians-Universität MünchenTheresienstrasse 3980333 MunichGermany University of freiburg Ernst-Zermelo-Strasse 179104 FreiburgGermany

We present a probabilistic construction of R^(d)-valued non-linear affine processes with *** a setΘof affine parameters,we define a family of sublinear expectations on the Skorokhod space under which the canonical process X is a(sublinear)Markov process with a non-linear *** yields a tractable model for Knightian uncertainty for which the sublinear expectation of a Markovian functional can be calculated via a partial integro-differential equation.

关键词： Sublinear expectation Non-linear affine processes dynamic programming PIdE

findr:A web server for in silico d-peptide ligand identification

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Synthetic and Systems Biotechnology 2021年第4期6卷 402-413页

作者： Helena Engel Felix Guischard Fabian Krause Janina Nandy Paulina Kaas Nico Hofflin Maja Kohn Normann Kilb Karsten Voigt Steffen Wolf Tahira Aslan Fabian Baezner Salom´e Hahne Carolin Ruckes Joshua Weygant Alisa Zinina Emir Bora Akmeriç Enoch B.Antwi dennis dombrovskij Philipp Franke Klara L.Lesch Niklas Vesper daniel Weis Nicole Gensch Barbara di Ventura Mehmet Ali Oztürk Signalling Research Centres BIOSS and CIBSS University of FreiburgSchanzlestr.1879104FreiburgGermany Institute of Biology III Faculty of BiologyUniversity of FreiburgSchanzlestr.179104FreiburgGermany Institute of Biology II Faculty of BiologyUniversity of FreiburgSchanzlestr.179104FreiburgGermany AG Roth-Lab for MicroarrayCopying ZBSA-Centre for Biological Systems AnalysisUniversity of FreiburgHabsburgerstrasse 4979104FreiburgGermany Biomolecular dynamics Institute of PhysicsUniversity of FreiburgHermann-Herder-Strasse 3a79104FreiburgGermany Core Facility Signalling Factory Centre for Biological Signaling Studies(BIOSS)University of FreiburgSchanzlestr.1879104FreiburgGermany Spemann Graduate School of Biology and Medicine(SGBM) University of FreiburgAlbertstraße 19A79104FreiburgGermany Internal Medicine IV Department of MedicineMedical CenterUniversity of FreiburgHugstetter Straße 5579106FreiburgGermany Institute for Biochemistry University of FreiburgAlbertstr.2179104FreiburgGermany

In the rapidly expanding field of peptide therapeutics,the short in vivo half-life of peptides represents a considerable limitation for drug action.d-peptides,consisting entirely of the dextrorotatory enantiomers of naturally occurring levorotatory amino acids(AAs),do not suffer from these shortcomings as they are intrinsically resistant to proteolytic degradation,resulting in a favourable pharmacokinetic *** experimentally identify d-peptide binders to interesting therapeutic targets,so-called mirror-image phage display is typically performed,whereby the target is synthesized in d-form and L-peptide binders are screened as in conventional phage *** technique is extremely powerful,but it requires the synthesis of the target in d-form,which is challenging for large *** we present findr,a novel web server for the computational identification and optimization of d-peptide ligands to any protein structure(https://***/).findr performs molecular docking to virtually screen a library of helical 12-mer peptides extracted from the RCSB Protein data Bank(PdB)for their ability to bind to the *** a separate,heuristic approach to search the chemical space of 12-mer peptides,findr executes a customizable evolutionary algorithm(EA)for the de novo identification or optimization of d-peptide *** a proof of principle,we demonstrate the validity of our approach to predict optimal binders to the pharmacologically relevant target phenol soluble modulin alpha 3(PSMα3),a toxin of methicillin-resistant Staphylococcus aureus(MRSA).We validate the predictions using in vitro binding assays,supporting the success of this *** to conventional methods,findr provides a low cost and easy-to-use alternative for the identification of d-peptide ligands against protein targets of choice without size *** believe findr will facilitate d-peptide discovery with implications in biotechnology and biomedicine.

关键词： d-peptide Web server Evolutionary algorithm Peptide design Molecular docking Mirror-image phage display

Auxin as a Model for the Integration of Hormonal Signal Processing and Transduction

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Molecular Plant 2008年第2期1卷 229-237页

作者： W.d. Teale F.A. ditengou A.d. dovzhenko X. Li A.M. Molendijk B. Ruperti I. Paponov K. Palme Institute of Biology Ⅱ Faculty of Biology University of Freiburg D-79104 Freiburg Germanya dipartimento di Agronomia Ambientale e Produzioni Vegetali Agripolis University of Padova viale dell'Universita 16 35020 Legnaro Italy

The regulation of plant growth responds to many stimuli. These responses allow environmental adaptation, thereby increasing fitness. In many cases, the relay of information about a plant＇s environment is through plant hormones. These messengers integrate environmental information into developmental pathways to determine plant shape. This re- view will use, as an example, auxin in the root ofArabidopsis thaliana to illustrate the complex nature of hormonal signal processing and transduction. It will then make the case that the application of a systems-biology approach is necessary, if the relationship between a plant＇s environment and its growth/developmental responses is to be properly understood.

关键词： Auxin as a Model Integration Processing and Transduction