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Journal of Magnesium and Alloys 2017年第2期5卷 173-180页

作者： tomas kekule Bohumil Smola Martin Vlach Hana Kudrnova Veronika Kodetova Ivana Stulikova Charles University in Prague Faculty of Mathematics and PhysicsKe Karlovu 3Praha 212116Czech Republic

Response to isochronal annealing up to 440 ℃ of squeeze cast Mg–Y–Zn alloy and of the same alloy prepared by powder metallurgy(PM)and extruded at 280 ℃ was studied by resistivity and microhardness measurement,differential scanning calorimetry(DSC)and microstructure *** resistivity was measured at 77 K and microhardness was measured at room temperature after each annealing *** measurement was performed at various heating *** and scanning electron microscopy and optical microscopy revealed ribbons of long-period ordered structure(LPSO)18R and planar defects within grain *** high density of planar defects was found in grain interiors of the cast alloy with the grain size approximately 50μ*** pronounced subgrains were observed in the PM prepared *** phase particles decorate grain boundaries in this *** precipitation processes were detected in the cast alloy during repeated isochronal annealing up to 440 ℃,whereas only one significant process was revealed in the PM *** processes were identified as embedding of stacking faults by solutes,development and rearrangement(18R→14H)of LPSO phase and development of grain boundary particles.A coarsening of grain boundary particles rich in Y and Zn only proceeds in the PM *** energies of the precipitation processes were *** exhibits good thermal stability against annealing up to 360 ℃ in the PM alloy.

关键词： Mg-Y-Zn alloys Powder metallurgy Microhardness Microstructure development Electrical resistivity

Insights from a proteomic atlas of human Alzheimer's disease brain tissue

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Neural Regeneration Research 2025年第3期20卷 799-800页

作者： tomas Kavanagh Eleanor Drummond Brain and Mind Centre and School of Medical Sciences University of SydneyCamperdownNSWAustralia

There is an urgent need to identify new drug targets for Alzheimer's disease(AD). While new immunotherapies show promise, clinical benefit appears low, and side effects are high. A greater understanding of the disease mechanisms driving AD is an essential factor that will facilitate the identification of new, effective drug targets.

关键词： Alzheimer clinical driving

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Wafer‑Scale Ag_(2)S‑Based Memristive Crossbar Arrays with Ultra‑Low Switching‑Energies Reaching Biological Synapses

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Nano-Micro Letters 2025年第3期17卷 328-339页

作者： Yuan Zhu tomas Nyberg Leif Nyholm Daniel Primetzhofer Xun Shi Zhen Zhang Division of Solid‑State Electronics Department of Electrical EngineeringUppsala University75121 UppsalaSweden Department of Chemistry Uppsala UniversityUppsalaSweden Department of Physics and Astronomy Uppsala UniversityUppsalaSweden State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050People’s Republic of China

Memristive crossbar arrays(MCAs)offer parallel data storage and processing for energy-efficient neuromorphic ***,most wafer-scale MCAs that are compatible with complementary metal-oxide-semiconductor(CMOS)technology still suffer from substantially larger energy consumption than biological synapses,due to the slow kinetics of forming conductive paths inside the memristive *** we report wafer-scale Ag_(2)S-based MCAs realized using CMOS-compatible processes at temperatures below 160℃.Ag_(2)S electrolytes supply highly mobile Ag+ions,and provide the Ag/Ag_(2)S interface with low silver nucleation barrier to form silver filaments at low energy *** further enhancing Ag+migration in Ag_(2)S electrolytes via microstructure modulation,the integrated memristors exhibit a record low threshold of approximately−0.1 V,and demonstrate ultra-low switching-energies reaching femtojoule values as observed in biological *** low-temperature process also enables MCA integration on polyimide substrates for applications in flexible ***,the intrinsic nonidealities of the memristive units for deep learning can be compensated by employing an advanced training *** impressive accuracy of 92.6%in image recognition simulations is demonstrated with the MCAs after the *** demonstrated MCAs provide a promising device option for neuromorphic computing with ultra-high energy-efficiency.

关键词： Wafer-scale Ag_(2)S films Reactive sputter Silver nucleation Ag^(+)migration Energy-efficient neuromorphic computing

Stepwise assembly to construct stable copper(I) cluster-based circularly polarized luminescent MOFs

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Science China Chemistry 2025年

作者： Jing-Wen Xie Meng-Ting Wang Yan Jin Si Li Jian-Hua Qin Shuang-Quan Zang tomas C.W.Mak College of Chemistry Henan Key Laboratory of Crystalline Molecular Functional Materials Zhengzhou University College of Chemistry and Chemical Engineering Luoyang Normal University Department of Chemistry The Chinese University of Hong Kong

Circularly polarized luminescence （CPL） materials have been extensively studied in recent years owing to their widespread applications in 3D display,optical storage,optical anti-counterfeiting,and biological imaging,***（I） clusters have emerged as a promising candidate for CPL materials,driven by their cost-effectiveness,superior luminescent properties,precise structure,and low ***,the poor environmental stability of copper（I） clusters renders their synthesis and preservation challenging,thereby significantly impeding their ***,we have designed and synthesised a chiral double-coordinated ligand in order to construct copper（I） cluster nodes that can be further *** anticipated,by utilizing stepwise assembly strategy,a Cu4cluster node co-modified by chiral alkynyl ligands and triphenylphosphine was further assembled with Cd2+ions to obtain 2D layers structure,L/*** L/D-Cu4-Cd exhibits excellent stability and optical properties,including bright yellow emission,solvent-responsive luminescence,and CPL activity with a maximum glumup to 2.0×10-3,which shows potential applications in the WLED and *** interestingly,the material also exhibits deflection ability towards different wavelengths of linearly polarized light,showing certain potential in the preparation of circular polarizer.

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New regulators of systemic iron homeostasis

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Signal Transduction and Targeted Therapy 2021年第8期6卷 2270-2271页

作者： tomas Ganz Center for Iron Disorders Department of MedicineDavid Geffen School of MedicineUCLALos AngelesCAUSA

In a recent study published in Blood,Jiang et al.1 describe two new mechanisms that may contribute to systemic iron *** first identify the methylcytosine dioxygenase Tetl as an iron-dependent epigenetic regulator of multiple downstream target *** through the target genes,they go on to show that one of them,Rnf217,is a long-sought E3 ubiquitin ligase that regulates the degradation of the unique cellular iron exporter ferroportin in response to its ligand,the master iron-regulatory hormone hepcidin.

关键词： Blood homeostasis sought

DISCONTINUOUS GALERKIN CALCULATIONS FOR A NONLINEAR PDE MODEL OF DNA TRANSCRIPTION WITH SHORT, TRANSIENT AND FREQUENT PAUSING

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Journal of Computational Mathematics 2014年第6期32卷 601-629页

作者： Lisa Davis tomas Gedeon Department of Mathematical Sciences Montana State University P.O. Box 172400 Bozeman MT 59717

A discontinuous Galerkin finite element method is used to approximate solutions to a classical traffic flow PDE. This PDE is used to model the biological process of transcription; the process of transferring genetic information from DNA either to mRNA or to rRNA. The transcription process is punctuated by short, frequent RNAP pauses which are incorporated into the model as traffic lights. These pauses cause a delay in the average transcription process. The DG solution of the nonlinear model is used to calculate the delay and to determine the effect of the pauses on the average transcription time. Numerical error measurements between the DG solution and the true solution （derived by the method of characteristics） are given for a simple model problem. It shows an excellent agreement in a neighborhood away from the shocks as well as C9（Ax） convergence for the delay calculation. Preliminary parameter studies indicate that in a system with multiple pauses both the location and time duration of the pauses can significantly affect the average delay experienced by an RNAP.

关键词： Discontinuous Galerkin finite element method Transcription LWR traffic flowmodel.

Fast Modification of Microdischarge Emission Bands by Fracture of Sugar

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Chinese Physics Letters 2011年第8期28卷 304-306页

作者： Sergej Aman Juergen tomas AStreletskii Otto-von-Guericke University MagdeburgP.O.Box 412039106 MagdeburgGermany Institute of Chemical Physics RASKosygina 4Moscow 119991Russia

Intensive light pulses with widths of about 10 ns were observed during the crack propagation by cleavage of crystalline sugar at atmospheric *** observed light pulses were caused by a sequence of gas microdischarges(MDs).The pulses were detected in the UV/VIS and NIR wavelength *** the light pulses appear in the UV/VIS wavelength range,and then after a delay of about 0.4–1.2 ns in the NIR wavelength *** characteristic feature of MDs can be used for the characterization of crack propagation.

关键词： delay sugar Fast

Neutral stochastic delay partial functional integro-differential equations driven by a fractional Brownian motion

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Frontiers of Mathematics in China 2013年第4期8卷 745-760页

作者： tomas CARABALLO Mamadou Abdoul DIOP Dpto. Ecuaciones Diferenciales y Analisis Numerico Universidad de Sevilla Apdo. de Correos 1160 41080-Sevilla Spain Universite Gaston Berger de Saint-Louis UFR SAT Departement de Mathematiques 234 Saint-Louis Senegal

This paper deals with the existence and uniqueness of mild solutions to neutral stochastic delay functional integro-differential equations perturbed by a fractional Brownian motion BH, with Hurst parameter H E （1/2, 1）. We use the theory of resolvent operators developed by R. Grimmer to show the existence of mild solutions. An example is provided to illustrate the results of this work.

关键词： Resolvent operator C0-semigroup Wiener process mild solution fractional Brownian motion

My Journey to DNA Repair

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Genomics, Proteomics & Bioinformatics 2013年第1期11卷 2-7页

作者： tomas Lindahl Cancer Research UK London Research Institute Clare Hall Laboratories

I completed my medical studies at the Karolinska Institute in Stockholm but have always been devoted to basic research. My longstanding interest is to understand fundamental DNA repair mechanisms in the fields of cancer therapy, inherited human genetic disorders and ancient DNA. I initially measured DNA decay, including rates of base loss and cytosine deamination. I have dis- covered several important DNA repair proteins and determined their mechanisms of action. The discovery of uracil-DNA glycosylase defined a new category of repair enzymes with each specialized for different types of DNA damage. The base excision repair pathway was first reconstituted with human proteins in my group. Cell-free analysis for mammalian nucleotide excision repair of DNA was also developed in my laboratory. I found multiple distinct DNA ligases in mammalian cells, and led the first genetic and biochemical work on DNA ligases I, III and IV. I discovered the mam- malian exonucleases DNase III （TREX1） and IV （FEN1）. Interestingly, expression of TREXI was altered in some human autoimmune diseases. I also showed that the mutagenic DNA adduct O6-methylguanine （O6mG） is repaired without removing the guanine from DNA, identifying a sur- prising mechanism by which the methyl group is transferred to a residue in the repair protein itself. A further novel process of DNA repair discovered by my research group is the action of AlkB as an iron-dependent enzyme carrying out oxidative demethylation.

关键词： DNA repair Base excision repair DNA glycosylase DNA exonuclease AlkB dioxygenase

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Simulation and calibration of granules using the discrete element method

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Particuology 2014年第1期12卷 40-43页

作者： Peter Müller Jürgen tomas Institute of Process Engineering Mechanical Process EngineeringOtto-von-Guericke University MagdeburgUniversitätsplatz 239106 MagdeburgGermany

The discrete element method （DEM）, developed by Cundall and 5track to solve geomecnamcai problems, is used to simulate the mechanical behavior of granules. According to the DEM, an individ ual granule can be modeled as a realistic mechanical system consisting of primary particles bonded by interaction forces. Cranulometric properties of the model material, zeolite 4A, have been measured to determine their macro properties. To investigate the compression behavior, a compression test was performed using a strength tester on single granules between two pistons. A modeled granule consisting of more than 22,000 primary particles was generated. The micro properties of the modeled granule have been precisely set to allow its macro properties to be equivalent to the macro properties of zeolite 4A granules. To calibrate the mechanical properties, diametrical compression was simulated using two rigid walls stressed at a constant stressing velocity, The force-displacement curve of the modeled granule at compression has been calibrated by the experimental curve of zeolite 4A.

关键词： Discrete element method Material behavior Granulation

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