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On self-affine tiles that are homeomorphic to a ball

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Science China Mathematics 2024年第1期67卷 45-76页

作者： jorg M.Thuswaldner Shu-Qin Zhang Mathematics and Statistics University of LeobenLeoben 8700Austria School of Mathematics and Statistics Zhengzhou UniversityZhengzhou 450001China

Let M be a 3×3 integer matrix which is expanding in the sense that each of its eigenvalues is greater than 1 in modulus and let d?Z^(3)be a digit set containing|det M|elements.Then the unique nonempty compact set T=T(M,d)defined by the set equation MT=T+d is called an integral self-affine tile if its interior is nonempty.If d is of the form d={0,v,...,(|det M|-1)v},we say that T has a collinear digit set.The present paper is devoted to the topology of integral self-affine tiles with collinear digit sets.In particular,we prove that a large class of these tiles is homeomorphic to a closed 3-dimensional ball.Moreover,we show that in this case,T carries a natural CW complex structure that is defined in terms of the intersections of T with its neighbors in the lattice tiling{T+z:z∈Z^(3)}induced by T.This CW complex structure is isomorphic to the CW complex defined by the truncated octahedron.

关键词： self-afine sets tiles and tilings low-dimensional topology truncated octahedron

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Molecular Plant 2012年第4期5卷 951-954页

作者： Giuseppe Ortu Raffaella Balestrini Patricia A. Pereira jorg d. becker Helge Kuste Paola Bonfante department of Life Science and Systems Biology University of Torino Italy Istituto per la Protezione delle Piante--CNR Torino Italy Instituto Gulbenkian de Ciencia 2780-156 Oeiras Portugal Institut for Pflanzengenetik Leibniz Universitat Hannover Herrenhauser Str. 2 D-30419 Hannover Germany

dear Editor, Phytohormones are essential regulators of plant develop- ment, but their role in the signaling processes between plants and fungi during arbuscular mycorrhizal （AM） establishment is far from being understood （Ludwig-M011er, 2010）. AM coloni- zation leads to extensive effects on host metabolism, as revealed by transcriptome studies of AM plants （Hogekamp et al., 2011）. Some genes have been specified as an AM core set, since they are mycorrhizal-responsive, irrespective of the identity of the plant,

关键词： AM真菌植物激素相关基因早期阶段调节过程生物合成相互作用赤霉素

A Transcriptome Atlas of Physcomitrella patens Provides Insights into the Evolution and development of Land Plants

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Molecular Plant 2016年第2期9卷 205-220页

作者： Carlos Ortiz-Ramirez Marcela Hernandez-Coronado Anna Thamm Bruno Catarino Mingyi Wang Liam dolan Jose A.Feijo jorg d. becker Instituto Gulbenklan de Ciencia Rua da Quinta Grande 6 2780-156 Oeiras Portugal department of Plant Sciences University of Oxford South Parks Road Oxford OX1 3RB UK division of Plant Biology The Samuel Roberts Noble Foundation Ardmore OK 73401 USA department of Cell Biology and Molecular Genetics University of Maryland 0118 BioSclence Research Building College Park MD 20742-5815 USA These authors contributed equally to this article

Identifying the genetic mechanisms that underpin the evolution of new organ and tissue systems is an aim of evolutionary developmental biology. Comparative functional genetic studies between angiosperms and bryophytes can define those genetic changes that were responsible for developmental innovations. Here, we report the generation of a transcriptome atlas covering most phases in the life cycle of the model bryo- phyte Physcomitrella patens, including detailed sporophyte developmental progression. We identified a comprehensive set of sporophyte-specific transcription factors, and found that many of these genes have homologs in angiosperms that function in developmental processes such as flowering and shoot branching. deletion of the PpTCP5 transcription factor results in development of supernumerary sporangia attached to a single seta, suggesting that it negatively regulates branching in the moss sporophyte. Given that TCP genes repress branching in angiosperms, we suggest that this activity is ancient. Finally, compar- ison of P. patens and Arabidopsis thaliana transcriptomes led us to the identification of a conserved core of transcription factors expressed in tip-growing cells. We identified modifications in the expression patterns of these genes that could account for developmental differences between P. patens tip-growing cells and A. thaliana pollen tubes and root hairs.

关键词： land plant evolution Physcomitrella patens transcriptome atlas TCP branching tip growth

Metabolic collaboration between cells in the tumor microenvironment has a negligible effect on tumor growth

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The Innovation 2024年第2期5卷 107-114页

作者： Johan Gustafsson Fariba Roshanzamir Anders Hagnestål Sagar M.Patel Oseeyi I.daudu donald F.becker Jonathan L.Robinson Jens Nielsen department of Life Sciences Chalmers University of TechnologySE-41296 GothenburgSweden Hagnesia AB SE-43854 HindåsSweden department of Biochemistry and Redox Biology Center University of Nebraska-LincolnLincolnNE 68588USA BioInnovation Institute DK2200 CopenhagenDenmark

The tumor microenvironment is composed of a complex mixture of different cell types interacting under conditions of nutrient deprivation,but the metabolism therein is not fully understood due to difficulties in measuring metabolic fluxes and exchange of metabolites between different cell types in vivo.Genome-scale metabolic modeling enables estimation of such exchange fluxes as well as an opportunity to gain insight into the metabolic behavior of individual cell types.Here,we estimated the availability of nutrients and oxygen within the tumor microenvironment using concentration measurements from blood together with a metabolite diffusion model.In addition,we developed an approach to efficiently apply enzyme usage constraints in a comprehensive metabolic model of human cells.The combined modeling reproduced severe hypoxic conditions and the Warburg effect,and we found that limitations in enzymatic capacity contribute to cancer cells’preferential use of glutamine as a substrate to the citric acid cycle.Furthermore,we investigated the common hypothesis that some stromal cells are exploited by cancer cells to produce metabolites useful for the cancer cells.We identified over 200 potential metabolites that could support collaboration between cancer cells and cancer-associated fibroblasts,but when limiting to metabolites previously identified to participate in such collaboration,no growth advantage was observed.Our work highlights the importance of enzymatic capacity limitations for cell behaviors and exemplifies the utility of enzyme-constrained models for accurate prediction of metabolism in cells and tumor microenvironments.

关键词： metabolism effect limitations

Application of ACP Nonlinear Math in Analyzing Arithmetic and Radiation Transmission data (Application 1 & 2) [4-21-2024, 820P] (V)

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Journal of Applied Mathematics and Physics 2024年第6期12卷 2302-2319页

作者： Ralph W. Lai Melisa W. Lai-becker Grace Cheng-dodge 28 Cornerstone Ct. Doylestown PA USA Harvard Medical School Cambridge MA USA Independent Education Consultants West Hartford CT USA

In this study, we explore the application of ACP (asymptotic curve based and proportionality oriented) Alpha Beta (αβ) Nonlinear Math to analyze arithmetic and radiation transmission data. Specifically, we investigate the relationship between two variables. The novel approach involves collecting elementary “y” data and subsequently analyzing the asymptotic cumulative or demulative (opposite of cumulative) Y data. In part I, we examine the connection between the common linear numbers and ideal nonlinear numbers. In part II, we delve into the relationship between X-ray energy and the radiation transmission for various thin film materials. The fundamental physical law asserts that the nonlinear change in continuous variable Y is negatively proportional to the nonlinear change in continuous variable X, expressed mathematically as dα = −Kdβ. Here: dα {Y, Yu, Yb} represents the change in Y, with Yu and Yb denoting the upper and baseline asymptote of Y. dβ {X, Xu, Xb} represents the change in X, with Xu and Xb denoting the upper and baseline asymptote of X. K represents the proportionality constant or rate constant, which varies based on equation arrangement. K is the key inferential factor for describing physical phenomena.

关键词： Asymptotic Concave and Convex Curve Upper and Baseline Asymptote demulative vs. Cumulative Coefficient of determination Proportionalityand Position Constant Skewed Bell and Sigmoid Curve

Temperature difference and Stack Plate Spacing Effects on Thermodynamic Performances of Standing-Wave Thermoacoustic Engines driven by Cryogenic Liquids and Waste Heat

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Journal of Thermal Science 2022年第5期31卷 1434-1451页

作者： GUO Lixian ZHAO dan becker Sid department of Mechanical Engineering College of EngineeringUniversity of CanterburyPrivate Bag 4800Christchurch8041New Zealand

The standing-wave thermoacoustic engines(TAE)are applied in practice to convert thermal power into acoustic one to generate electricity or to drive cooling devices.Although there is a number of existing numerical researches that provides a design tool for predicting standing-wave TAE performances,few existing works that compare TAE driven by cryogenic liquids and waste heat,and optimize its performance by varying the stack plate spacing.This present work is primarily concerned with the numerical investigation of the performance of TAEs driven by cryogenic liquids and waste heat.For this,three-dimensional(3-d)standing-wave TAE models are developed.Mesh-and time-independence studies are conducted first.Model validations are then performed by comparing with the numerical results available in the literature.The validated model is then applied to simulate the standing-wave TAEs driven by the cryogenic liquids and the waste heat,as the temperature gradientΔT is varied.It is found that limit cycle oscillations in both systems are successfully generated and the oscillations amplitude is increased with increasedΔT.Nonlinearity is identified with acoustic streaming and the flow reversal occurring through the stack.Comparison studied are then conducted between the cryogenic liquid-driven TAE and that driven by waste heat in the presence of the same temperature gradientΔT.It is shown that the limit cycle frequency of the cryogenic liquid system is 4.72%smaller and the critical temperatureΔT_(cri)=131 K is lower than that of the waste heat system(ΔT_(cri)=187 K).Furthermore,the acoustic power is increased by 31%and the energy conversion efficiency is found to increase by 0.42%.Finally,optimization studies on the stack plate spacing are conducted in TAE system driven by cryogenic liquids.It is found that the limit cycle oscillation frequency is increased with the decreased ratio between the stack plate spacing and the heat penetration depth.When the ratio is set to between 2 and 3,the overall performance of the cryogenic liqui

关键词： thermoacoustic engine standing-wave cryogenic thermodynamics acoustical energy plate spacing heat transfer acoustic streaming

The Properties and Applications of MoS_2/Ti Composite Coatings in dry Cutting and Forming

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材料热处理学报 2004年第5B期25卷 894-898页

作者： XiaolingZhang HailinSun d.becker S.Wagner d.G.Teer TeerCoatingsLtd. WestStineHouseBerryHillIndustrialEstateDroitwichWorcestershireUK InstituteforMetalFormingTechnology stuttgartUniversityStuttgartGermany

MoSi/Ti composite coatings (MoST?), have been deposited by a closed-field unbalanced magnetron sputter ion-plating system. The high ion-current densities at low substrate bias voltage of the system ensures that the MoST? coatings are characteristic of dense coherent structures, with high adhesion (critical scratch load above 120 N), high load bearing capacity up to 5 GPa., low friction (0.02-0.1), high wear resistance (less than 4xlO"17 m3/N m) even at a relative humidity of 40%, and high temperature resistance up to 350 °C. The successful applications of MoST? coatings in large- scale productions for dry cutting and forming, with increasing lifetime and productivity are presented.

关键词： MoS2/Ti复合涂层干切割低摩擦力磁控管溅射

data-driven prediction of plate velocities and plate deformation of explosive reactive armor

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defence Technology（防务技术） 2022年第12期18卷 2141-2149页

作者： Marvin becker Andreas Klavzar Thomas Wolf Melissa Renck Institute of Saint-Louis 5 Rue du Général Cassagnou68330Saint LouisCedexFrance Ecole Centrale de Lille CitéScientifique59651Villeneuve d'AscqCedexFrance

Explosive reactive armor(ERA)is currently being actively developed as a protective system for mobile devices against ballistic threats such as kinetic energy penetrators and shaped-charge jets.Considering mobility,the aim is to design a protection system with a minimal amount of required mass.The efficiency of an ERA is sensitive to the impact position and the timing of the detonation.Therefore,different designs have to be tested for several impact scenarios to identify the best design.Since analytical models are not predicting the behavior of the ERA accurately enough and experiments,as well as numerical simulations,are too time-consuming,a data-driven model to estimate the displacements and deformation of plates of an ERA system is proposed here.The ground truth for the artificial neural network(ANN)is numerical simulation results that are validated with experiments.The ANN approximates the plate positions for different materials,plate sizes,and detonation point positions with sufficient accuracy in real-time.In a future investigation,the results from the model can be used to estimate the interaction of the ERA with a given threat.Then,a measure for the effectiveness of an ERA can be calculated.Finally,an optimal ERA can be designed and analyzed for any possible impact scenario in negligible time.

关键词： Artificial neural network Explosive reactive armor Finite element simulation Particle simulation Flash X-ray

Acid tolerance of lactate-utilizing bacteria of the order Bacteroidales contributes to prevention of ruminal acidosis in goats adapted to a high-concentrate diet

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Animal Nutrition 2023年第3期14卷 130-140页

作者： Zhongyan Lu Lingmeng Kong Shenhao Ren jorg RAschenbach Hong Shen Key Lab of Animal Physiology and Biochemistry College of Veterinary MedicineNanjing Agricultural UniversityNanjingJiangsuChina College of Life Science Nanjing Agricultural UniversityNanjingJiangsuChina Institute of Veterinary Physiology Freie Universitat BerlinBerlinGermany Bioinformatics Center Academy for Advanced Interdisciplinary StudiesNanjing Agricultural UniversityNanjingJiangsuChina

The rapid accumulation of organic acids,particularly lactate,has been suggested as the main cause of ruminal acidosis(RA)for ruminants fed high-concentrate diets.Previous research has shown that a gradual shift from low-to high-concentrate diets within 4 to 5 weeks effectively reduces the risk for RA.However,the mechanisms remain unknown.In this study,20 goats were randomly allocated into four groups(n=5)and fed with a diet containing a weekly increasing concentrate portion of 20%,40%,60%,and 80%over 28 d.At d 7,14,21,and 28,one group(named C20,C40,C60,and C80 according to the last concentrate level that they received)was killed and the ruminal microbiome was collected.Ruminal acidosis was not detected in any of the goats during the experiment.Nonetheless,ruminal pH dropped sharply from 6.2 to 5.7(Pdietary concentrate increased from 40%to 60%.A combined metagenome and metatranscriptome sequencing approach identified that this was linked to a sharp decrease in the abundance and expression of genes encoding nicotinamide adenine dinucleotide(NAd)-dependent lactate dehydrogenase(nLdH),catalyzing the enzymatic conversion of pyruvate to lactate(Pding NAd-independent lactate dehydrogenase(iLdH),catalyzing lactate oxidation to pyruvate,showed no significant concomitant change.Abundance and expression alterations for nLdH-and iLdH-encoding genes were attributable to bacteria from Clostridiales and Bacteroidales,respectively.By analyzing the gene profiles of 9 metagenome bins(MAG)with nLdH-encoding genes and 5 MAG with iLdH-encoding genes,we identified primary and secondary active transporters as being the major types of sugar transporter for lactate-producing bacteria(LPB)and lactate-utilizing bacteria(LUB),respectively.Furthermore,more adenosine triphosphate was required for the phosphorylation of sugars to initiate their catabolic pathways in LPB compared to LUB.Thus,the low dependence of sugar transport systems and catabolic pathways on primary energy sources su

关键词： Ruminal microbiome Ruminal acidosis Acid tolerance Lactate metabolism