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A Linearization Approach for Rational Nonlinear Models in Mathematical Physics

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Communications in Theoretical Physics 2012年第4期57卷 530-540页

作者： robert A.van Gorder Department of Mathematics University of Central FloridaP.O.Box 161364OrlandoFL 32816-1364USA

In this paper, a novel method for linearization of rational second order nonlinear models is discussed. In particular, we discuss an application of the 5 expansion method （created to deal with problems in Quantum Field Theory） which will enable both the linearization and perturbation expansion of such equations. Such a method allows for one to quickly obtain the order zero perturbation theory in terms of certain special functions which are governed by linear equations. Higher order perturbation theories can then be obtained in terms of such special functions. One benefit to such a method is that it may be applied even to models without small physical parameters, as the perturbation is given in terms of the degree of nonlinearity, rather than any physical parameter. As an application, we discuss a method of linearizing the six Painlev~ equations by an application of the method. In addition to highlighting the benefits of the method, we discuss certain shortcomings of the method.

关键词： perturbation method Painleve equations δ-expansion nonlinear differential equations

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Sodium lanthanide fluoride core-shell nanocrystals： A general perspective on epitaxial shell growth

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Nano Research 2013年第8期6卷 547-561页

作者： Noah j. j. j.hnson Frank C. j. M. van Veggel Department of Chemistry University ofVictoria P.O. Box3065 Victoria British Columbia Canada V8W 3V6

Understanding the structural characteristics and growth mechanism（s） are essen-tial for generating core-shell nano-heterostructures with distinctive properties. Especially in lanthanide-based nanocrystals, rational design of the core-shell composition can be utilized to enhance/tune the optical properties of the final nanostructure, or can be used to integrate multiple functional applications （e.g., luminescent/magnetic）. In this article, we review the progress in our current understanding of the epitaxial shell growth in sodium lanthanide fluoride （NaLnF4） nanocrystals. In order to understand epitaxial shell growth the core nanocrystals have to be uniform, and to date the synthesis of high quality near uniform size/shape dispersion controlled synthesis of lanthanide-based nanocrystals has been achieved mainly with this class of nanocrystals. The progress in core-shell synthesis and the epitaxial shell growth mechanism in this class of nanocrystals （NaLnF4） are reviewed, and a general perspective is provided on the core-shell morphology based on different characterization techniques. While there has been tremendous progress in studying the impact of core-shell structures in various functional applications, this review also highlights, in our view, the still limited understanding of ways to control the core-shell morphology and it emphasizes some important, unanswered questions that remain to be addressed to maximize their performance.

关键词： upconvertingnanocrystals core-shell lanthanides epitaxy

Solutions to a Novel Casimir Equation for the Ito System

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Communications in Theoretical Physics 2011年第11期56卷 801-804页

作者： robert A.van Gorder Department of Mathematics University of Central Florida Orlando

We discuss two classes of solutions to a novel Casimir equation associated with the Ito system,a couplednonlinear wave *** travelling wave solutions and separable self-similar solutions are *** a numberof cases,explicit exact solutions are *** results,particularly the exact solutions,are useful in that they provideus a baseline of comparison to any numerical ***,such solutions provide us a glimpse of the behaviorof the Ito system,and hence the behavior of a type of nonlinear wave equation,for certain parameter regimes.

关键词： nonlinear wave equation Ito system travelling waves self-similar solutions

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Advances in scalable gas-phase manufacturing and processing of nanostructured solids： A review

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Particuology 2017年第1期15卷 15-39页

作者： Samir Salameh j.sus Gomez-Hernandez Aristeidis Goulas Hao van Bui j. Ruud van Ommen Delft University ofTechnology Julianalaan 136 2628 BL Delft The Netherlands Carlos III University of Madrid Avda. de la Universidad 30 28911 Leganes Madrid Spain Delft IMP B.V. Mekelweg 2 2628 CD Delft The Netherlands

Although the gas-phase production of nanostructured solids has already been carried out in industry for decades, only in recentyears has research interest in this topic begun to increase. Nevertheless, despite the remarkable scientific progress made recently, many long-established processes are still used in industry. Scientific advancements can potentially lead to the improvement of existing industrial processes, but also to the development of completely new routes. This paper aims to review state-of-the-art synthesis and processing technologies, as well as the recent developments in academic research. Flame reactors that produce inorganic nanoparticles on industrial- and lab-scales are described, alongside a detailed overview of the different systems used for the production of carbon nanotubes and graphene. We discuss the problems of agglomeration and mixing of nanoparticles, which are strongly related to synthesis and processing. Finally, we focus on two promising processing techniques, namely nanoparticle fluidization and atomic layer deposition.

关键词： Nanoparticle synthesis Gas-phase process Nanoparticle fluidization Atomic layer deposition Agglomeration

Surveillance for hepatocellular carcinoma in chronic liver disease:Evidence and controversies

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World j.urnal of Gastroenterology 2013年第40期19卷 6744-6756页

作者： Suzanne van Meer robert A de Man Peter D Siersema Karel j.van Erpecum Department of Gastroenterology and Hepatology University Medical Center Utrecht3508 GA UtrechtThe Netherlands Department of Gastroenterology and Hepatology Erasmus Medical Center3015 CE RotterdamThe Netherlands

Primary liver cancer is the sixth most common cancer in the world and the third cause of cancer-related *** carcinoma(HCC)represents more than90%of primary liver cancers and generally occurs in patients with underlying chronic liver disease such as viral hepatitis,hemochromatosis,primary biliary cirrhosis and non-alcoholic *** cirrhotic patients are at risk of HCC and regular surveillance could enable early detection and therapy,with potentially improved *** here summarize existing evidence for surveillance including ultrasound,other radiological modalities and various serum biomarkers,and current international guideline recommendations for *** andα-fetoprotein(alone or in combination)are most frequently used for surveillance,but their sensitivities and specificities are still far from perfect,and evidence for surveillance remains weak and *** other potential surveillance tools have been tested,including serum markers as des-carboxyprothrombin,lectin-boundα-fetoprotein,and(most recently)circulating TIE2-expressing monocytes,and radiological investigations such as computed tomographyscan or magnetic resonance *** early results appear promising,these tools have generally been tested in diagnostic rather than surveillance setting,and in most cases,no detailed information is available on their *** the near future,it remains important to define those patients with highest risk of HCC and most benefit from surveillance,and to restrict surveillance to these categories.

关键词： Hepatocellular carcinoma Surveillance Chronic liver disease

Modular-integrative modeling: a new framework for building brain models that blend biological realism and functional performance

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National Science Review 2024年第05期 13-16页

作者： Mario Senden Sacha j.van Albada Giovanni Pezzulo Egidio Falotico Ibrahim Hashim Alexander Kroner Anno C.Kurth Pablo Lanillos Vaishnavi Narayanan Cyriel Pennartz Mihai A.Petrovici Lea Steffen Tonio Weidler Rainer Goebel Department of Cognitive Neuroscience Maastricht University Maastricht Brain Imaging Centre Maastricht University Institute of Neuroscience and Medicine(INM-6) and Institute for Advanced Simulation(IAS-6) and j.RA-Institut Brain Structure-Function Relationships(INM-10) Jülich Research Center Institute of Zoology University of Cologne Institute of Cognitive Sciences and Technologies The Bio Robotics Institute Scuola Superiore Sant'Anna RWTH Aachen University Donders Institute for Brain Cognition and BehaviorRadboud University Cognitive and Systems Neuroscience Group Swammerdam Institute for Life Sciences University of Amsterdam Department of Physiology University of Bern FZI Research Center of Information Technology

To cope with the immense complexity of the brain, neuroscientific research often focuses on isolated brain structures or circumscribed perceptual, cognitive or motor functions [1]. This reductionist approach overlooks the intricate and multifaceted interplay among various structural and functional *** instance, even simple movements require the coordinated activation of numerous neuronal populations across multiple brain regions [2].

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Covering Your Bases： Inheritance of DNA Methylation in Plant Genomes

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Molecular Plant 2014年第3期7卷 472-480页

作者： Chad E. Niederhuth robert j. Schmitz Department of Genetics University of Georgia Athens GA 30602 USA

Cytosine methylation is an important base modification that is inherited across mitotic and meiotic cell divisions in plant genomes. Heritable methylation variants can contribute to within-species phenotypic variation. Few methylation variants were known until recently, making it possible to begin to address maj.r unanswered questions： the extent of natural methylation variation within plant genomes, its effects on phenotypic variation, its degree of depend- ence on genotype, and how it fits into an evolutionary context. Techniques like whole-genome bisulfite sequencing （WGBS） make it possible to determine cytosine methylation states at single-base resolution across entire genomes and populations. Application of this method to natural and novel experimental populations is revealing answers to these long-standing questions about the role of DNA methylation in plant genomes.

关键词： DNA methylation epigenetics epiallele whole-genome bisulfite sequencing.

Specifications of Targeting Heterochromatin Modifications in Plants

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Molecular Plant 2018年第3期11卷 381-387页

作者： j.red M. Wendte robert j. Schmitz Department of Genetics University of Georgia Athens GA 30602 USA

Plants encode a diverse repertoire of DNA methyltransferases that have specialized to target cytosines for methylation in specific sequence contexts. These include the de novo methyltransferase, DOMAINS REARRANGED METHYLTRANSFERASE 2 （DRM2）, which methylates cytosines in all sequence contexts through an RNA-guided process, the CHROMOMETHYLASES （CMTs）, which methylate CHH and CHG cytosines （where H is A, T, or C）, and METHYLTRANSFERASE 1 （MET1）, which maintains methylation of symmetrical CG contexts. In this review, we discuss the sequence specificities and targeting of each of these pathways. In particular, we highlight recent studies that indicate CMTs preferentially target CWG or CWA/CAW motifs （where W is A or T）, and discuss how self-reinforcing feedback loops between DNA methyltransferases and histone modifications characteristic of heterochromatin specify targeting. Finally, the initiating events that lead to gene body methylation are discussed as a model illustrating how interde- pendent targeting of different silencing pathways can potentiate the establishment of off-target epialleles.

关键词： heterochromatin DNA methylation gene body methylation epiallele DNA methyltransferase,chromomethylase

Adding Value to Crop Production Systems by Integrating Forage Cover Crop Grazing

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American j.urnal of Plant Sciences 2024年第3期15卷 180-192页

作者： robert B. Mitchell Daren D. Redfearn Kenneth P. Vogel Terry j. Klopfenstein Galen Erickson P. Stephen Baenziger Bruce E. Anderson Mary E. Drewnoski j.y Parsons Steven D. Masterson Marty R. Schmer Virginia L. j.n USDA-ARS Wheat Sorghum and Forage Research Unit University of Nebraska-Lincoln Lincoln NE USA Department of Agronomy and Horticulture University of Nebraska-Lincoln Lincoln NE USA Department of Animal Science University of Nebraska-Lincoln Lincoln NE USA Department of Agricultural Economics University of Nebraska-Lincoln Lincoln NE USA USDA-ARS Agroecosystem Management Research Unit University of Nebraska-Lincoln Lincoln NE USA

In addition to their value as cereal grains, wheat (Triticum aestivum L.) and triticale (× Triticosecale Wittmack) are important cool-season annual forages and cover crops. Yearling steer (Bos taurus) performance was compared in the spring following autumn establishment as for age cover crops after soybean [Glycine max (L.) Merr.] grain harvest. Replicated pastures (0.4 ha) were no-till seeded in three consecutive years into soybean stubble in autumn, fertilized, and grazed the following spring near Ithaca, NE, USA. Each pasture (n = 3) was continuously stocked in spring with four yearling steers (380 ± 38 kg) for 17, 32, and 28 d in 2005, 2006, and 2007, respectively. In 2005, average daily gain (ADG) for steers grazing triticale exceeded the ADG for wheat by 0.31 kghd-1d-1. In 2006, wheat ADG exceeded that for triticale by 0.12 kghd-1d-1. In 2007, steers grazing wheat lost weight, while steers grazing triticale gained 0.20 kghd-1d-1. Based on the 3-year average animal gains valued at $1.32 kg-1, mean net return ($ ha-1 yr-1) was $62.15 for triticale and $22.55 for wheat. Since these grazed cover crops provide ecosystem services in addition to forage, grazing could be viewed as a mechanism for recovering costs and adds additional value to the system. Based on this 3-year grazing trial, triticale was superior to wheat and likely will provide the most stable beef yearling performance across years with variable weather for the western Cornbelt USA.

关键词： Cover crops Soybean Triticale Wheat