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Wafer-Scale Ag₂S-Based Memristive Crossbar Arrays with Ultra-Low Switching-Energies Reaching Biological Synapses

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NANO-MICRO LETTERS 2025年第1期17卷 1-12页

作者： Zhu, Yuan Nyberg, tomas Nyholm, Leif Primetzhofer, Daniel Shi, Xun Zhang, Zhen Uppsala Univ Dept Elect Engn Div Solid State Elect S-75121 Uppsala Sweden Uppsala Univ Dept Chem Uppsala Sweden Uppsala Univ Dept Phys & Astron Uppsala Sweden Chinese Acad Sci Shanghai Inst Ceram State Key Lab High Performance Ceram & Superfine M Shanghai 200050 Peoples R China

Memristive crossbar arrays (MCAs) offer parallel data storage and processing for energy-efficient neuromorphic computing. However, 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 units. Here we report wafer-scale Ag2S-based MCAs realized using CMOS-compatible processes at temperatures below 160 degrees C. Ag2S electrolytes supply highly mobile Ag+ ions, and provide the Ag/Ag2S interface with low silver nucleation barrier to form silver filaments at low energy costs. By further enhancing Ag+ migration in Ag2S 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 synapses. The low-temperature process also enables MCA integration on polyimide substrates for applications in flexible electronics. Moreover, the intrinsic nonidealities of the memristive units for deep learning can be compensated by employing an advanced training algorithm. An impressive accuracy of 92.6% in image recognition simulations is demonstrated with the MCAs after the compensation. The demonstrated MCAs provide a promising device option for neuromorphic computing with ultra-high energy-efficiency.

关键词： Wafer-scale Ag2S films Reactive sputter Silver nucleation Ag+ migration Energy-efficient neuromorphic computing

Terpenoids as potential chemopreventive and therapeutic agents in liver cancer

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World Journal of Hepatology 2011年第9期3卷 228-249页

作者： roslin J Thoppil Anupam Bishayee Cancer Therapeutics and Chemoprevention Group Department of Pharmaceutical Sciences Northeastern Ohio Universities Colleges of Medicine and Pharmacy Department of Internal Medicine Northeastern Ohio Universities Colleges of Medicine and Pharmacy

Despite significant advances in medicine, liver cancer, predominantly hepatocellular carcinoma remains a major cause of death in the United States as well as the rest of the world. As limited treatment options are currently available to patients with liver cancer, novel preventive control and effective therapeutic approaches are considered to be reasonable and decisive measures to combat this disease. Several naturally occurring dietary and non-dietary phytochemicals have shown enormous potential in the prevention and treatment of several cancers, especially those of the gastrointestinal tract. Terpenoids, the largest group of phytochemicals, traditionally used for medicinal purposes in India and China, are currently being explored as anticancer agents in clinical trials. Terpenoids (also called "isoprenoids") are secondary metabolites occurring in most organisms, particularly plants. More than 40 000 individual terpenoids are known to exist in nature with new compounds being discovered every year. A large number of terpenoids exhibit cytotoxicity against a variety of tumor cells and cancer preventive as well as anticancer efficacy in preclinical animal models. This review critically examines the potential role of naturally occurring terpenoids, from diverse origins, in the chemoprevention and treatment of liver tumors. Both in vitro and in vivo effects of these agents and related cellular and molecular mechanisms are highlighted. Potential challenges and future directions involved in the advancement of these promising natural compounds in the chemoprevention and therapy of human liver cancer are also discussed.

关键词： Terpenoids Liver cancer cells Hepatocellular carcinoma Hepatocarcinogenesis Chemoprevention Treatment Apoptosis Cell cycle

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

The Global Soil Mycobiome consortium dataset for boosting fungal diversity research

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Fungal Diversity 2021年第6期111卷 573-588页

作者： Leho Tedersoo Vladimir Mikryukov Sten Anslan Mohammad Bahram Abdul Nasir Khalid Adriana Corrales Ahto Agan Aída-M.Vasco-Palacios Alessandro Saitta Alexandre Antonelli Andrea C.Rinaldi Annemieke Verbeken Bobby P.Sulistyo Boris Tamgnoue Brendan Furneaux Camila Duarte Ritter Casper Nyamukondiwa Cathy Sharp César Marín D.Q.Dai Daniyal Gohar Dipon Sharmah Elisabeth Machteld Biersma Erin K.Cameron Eske De Crop Eveli Otsing Evgeny A.Davydov Felipe E.Albornoz Francis Q.Brearley Franz Buegger Genevieve Gates Geoffrey Zahn Gregory Bonito Indrek Hiiesalu Inga Hiiesalu Irma Zettur Isabel C.Barrio Jaan Pärn Jacob Heilmann-Clausen Jelena Ankuda John Y.Kupagme Joosep Sarapuu Jose G.Maciá-Vicente Joseph Djeugap Fovo József Geml Juha M.Alatalo Julieta Alvarez-Manjarrez Jutamart Monkai Kadri Põldmaa Kadri Runnel Kalev Adamson Kari A.Bråthen Karin Pritsch Kassim I.Tchan Kęstutis Armolaitis Kevin D.Hyde Kevin K.Newsham Kristel Panksep Lateef A.Adebola Louis J.Lamit Malka Saba Marcela Eda Silva Cáceres Maria Tuomi Marieka Gryzenhout Marijn Bauters Miklós Bálint Nalin Wijayawardene Niloufar Hagh-Doust Nourou S.Yorou Olavi Kurina Peter E.Mortimer Peter Meidl RHenrik Nilsson Rasmus Puusepp Rebeca Casique-Valdés Rein Drenkhan Roberto Garibay-Orijel Roberto Godoy Saleh Alfarraj Saleh Rahimlou Sergei Põlme Sergey V.Dudov Sunil Mundra Talaat Ahmed Tarquin Netherway Terry W.Henkel tomas roslin Vladimir E.Fedosov Vladimir G.Onipchenko WAErandi Yasanthika Young Woon Lim Meike Piepenbring Darta Klavina Urmas Kõljalg Kessy Abarenkov Mycology and Microbiology Center University of TartuTartuEstonia Institute of Ecology and Earth Sciences TartuEstonia Department of Ecology Swedish University of Agricultural SciencesUppsalaSweden Department of Botany University of the PunjabQuaid-e-Azam CampusLahorePakistan Centro de Investigaciones en Microbiología y Biotecnología-UR(CIMBIUR) Facultad de Ciencias NaturalesUniversidad del RosarioBogotáColombia Grupo de Microbiología Ambiental y BioMicro Escuela de MicrobiologíaUniversidad de Antioquia UdeAMedellínColombia Department of Agricultural Food and Forest SciencesUniversity of PalermoPalermoItaly Royal Botanic Gardens SurreyUK Department of Biomedical Sciences University of CagliariCagliariItaly Research Group Mycology Department of BiologyGhent UniversityGhentBelgium Department of Biomedicine Indonesia International Institute for Life SciencesJakartaIndonesia Plant Pathology and Agricultural Zoology Research Unit Department of Plant ProtectionFaculty of Agronomy and Agricultural SciencesUniversity of DschangDschangCameroon Department of Ecology and Genetics Uppsala UniversityUppsalaSweden Eukaryotic Microbiology University of Duisburg-EssenEssenGermany Department of Biological Sciences and Biotechnology Botswana International University of Science and TechnologyPalapyeBotswana Natural History Museum of Zimbabwe BulawayoZimbabwe Institute of Botany Czech Academy of SciencesPrůhoniceCzech Republic Center for Yunnan Plateau Biological Resources Protection and Utilization College of Biological Resource and Food EngineeringQujing Normal UniversityQujingPeople’s Republic of China Department of Botany Jawaharlal Nehru Rajkeeya MahavidyalayaPondicherry UniversityPort BlairIndia British Antarctic Survey NERCCambridgeUK Natural History Museum of Denmark University of CopenhagenCopenhagenDenmark Department of Environmental Science Saint Mary’s UniversityHalifaxNSCanada Altai State University BarnaulRussia CSIRO Land and Water WembleyWAAustralia Department of N

Fungi are highly important biotic components of terrestrial ecosystems,but we still have a very limited understanding about their diversity and *** data article releases a global soil fungal dataset of the Global Soil Mycobiome consortium(GSMc)to boost further research in fungal diversity,biogeography and *** dataset comprises 722,682 fungal operational taxonomic units(OTUs)derived from PacBio sequencing of full-length ITS and 18S-V9 variable regions from 3200 plots in 108 countries on all *** plots are supplied with geographical and edaphic *** OTUs are taxonomically and functionally assigned to guilds and other functional *** entire dataset has been corrected by excluding chimeras,index-switch artefacts and potential *** dataset is more inclusive in terms of geographical breadth and phylogenetic diversity of fungi than previously published *** GSMc dataset is available over the PlutoF repository.

关键词： Soil fungi Global dataset PacBio sequencing Fungal richness

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

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