检索结果-南通市图书馆

Kaplansky Density and Kadison Transitivity Theorems for Irreducible Representations of Real C^-Algebras

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2007年第10期23卷 1827-1832页

作者： jeffrey l.BOERSEMA Department of Mathematics Seattle UniversitySeattleWA 98122USA

We prove analogs of the Kaplansky Density Theorem and the Kadison Transitivity Theorem for irreducible representations of a real C＊-algebra on a real Hilbert space. Specifically, if a C＊-algebra is acting irreducibly on a real Hilbert space, then the Hilbert space has either a real, complex, or quaternionic structure with respect to which the density and transitivity theorems hold.

关键词： real C*-algebra irreducible * representation transitivity

Reduced combustion time model for methane in gas turbine flow fields

在线全文

学校读者我要写书评

暂无评论

Journal of Natural Gas Chemistry 2009年第2期18卷 145-155页

作者： Mouna lamnaouer Robert C. Ryder Andreja Brankovic Eric l. petersen Graduate Research Assistant Mechanical Materials & Aerospace Engineering University of Central FloridaOrlando Fl 32816 USA President Engineering Flow ParametricsIvoryton CT USA Vice President Flow ParametricsIvoryton CT USA Associate Professor Department of Mechanical Engineering Texas A&M University College StationTX 77843 USA

Computational fluid dynamics （CFD） modeling of the complex processes that occur within the burner of a gas turbine engine has become a critical step in the design process. However, due to computer limitations, it is very difficult to completely couple the fluid mechanics solver with the full combustion chemistry. Therefore, simplified chemistry models are required, and the topic of this research was to provide reduced chemistry models for CH4/O2 gas turbine flow fields to be integrated into CFD codes for the simulation of flow fields of natural gas-fueled burners. The reduction procedure for the CH4/O2 model utilized a response modeling technique wherein the full mechanism was solved over a range of temperatures, pressures, and mixture ratios to establish the response of a particular variable, namely the chemical reaction time. The conditions covered were between 1000 and 2500 K for temperature, 0.1 and 2 for equivalence ratio in air, and 0.1 and 50 atm for pressure. The kinetic time models in the form of ignition time correlations are given in Arrhenius-type formulas as functions of equivalence ratio, temperature, and pressure; or fuel-to-air ratio, temperature, and pressure. A single ignition time model was obtained for the entire range of conditions, and separate models for the low-temperature and high-temperature regions as well as for fuel-lean and rich cases were also derived. Predictions using the reduced model were verified using results from the full mechanism and empirical correlations from experiments. The models are intended for （but not limited to） use in CFD codes for flow field simulations of gas turbine combustors in which initial conditions and degree of mixedness of the fuel and air are key factors in achieving stable and robust combustion processes and acceptable emission levels. The chemical time model was utilized successfully in CFD simulations of a generic gas turbine combustor with four different cases with various levels of fuel-air premixin

关键词： CH4 ignition time correlations reduced kinetic model

Relationships between Gene Structure and Genome Instability in Flowering Plants

在线全文

学校读者我要写书评

暂无评论

Molecular Plant 2018年第3期11卷 407-413页

作者： jeffrey l. Bennetzen Xuewen Wang State Key laboratory of Tea Plant Biology and Utilization/Key laboratory of Tea Biology and Processing Ministry of Agriculture Anhui Agricultural University HefeiAnhui 230036 People's Republic of China Department of Genetics University of Georgia Athens GA 30602 USA

Flowering plant （angiosperm） genomes are exceptional in their variability with respect to genome size, ploidy, chromosome number, gene content, and gene arrangement. Gene movement, although observed in some of the earliest plant genome comparisons, has been relatively underinvestigated. We present here- in a description of several interesting properties of plant gene and genome structure that are pertinent to the successful movement of a gene to a new location. These considerations lead us to propose a model that can explain the frequent success of plant gene mobility, namely that Small Insulated Genes Move Around （SlGMAR）. The SIGMAR model is then compared with known processes for gene mobilization, and predic- tions of the SIGMAR model are formulated to encourage future experimentation. The overall results indicate that the frequent gene movement in angiosperm genomes is partly an outcome of the unusual properties of angiosperm genes, especially their small size and insulation from epigenetic silencing.

关键词： epigenetic silencing gene insulators gene movement illegitimate recombination inaccurate DNA break repair transposon mobilization

Beyond dichotomies in species and speciation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

National Science Review 2022年第12期9卷 15-17页

作者： jeffrey l.Feder Patrik Nosil Department of Biological Sciences University of Notre Dame Centre d'Ecologie Fonctionnelle et Evolutive University MontpellierCNRS EPHE IRD

Speciation is not as mysterious as D arwin once described it [1].Nevertheless,important questions *** discussed by Wu[2] and highlighted in a series of papers in National Science Review (NSR),these issues equate with imposing dichotomous perspectives on speciation,when the nature of species and the processes creating them can complicate discrete categorization.

关键词：

Molecular mechanisms of the suppression of axon regeneration by KlF transcription factors

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2014年第15期9卷 1418-1421页

作者： Akintomide Apara jeffrey l.Goldberg University of Miami Miller School of Medicine MiamiFL USA Shiley Eye CenterUniversity of California San Diego La JollaCA USA

Molecular mechanisms of the Kruppel-like family of transcription factors （KlFs） have been studied more in proliferating cells than in post-mitotic cells such as neurons. We recently found that KlFs regulate intrinsic axon growth ability in central nervous system （CNS） neurons in- cluding retinal ganglion cells, and hippocampal and cortical neurons. With at least 15 of 17 KlF family members expressed in neurons and at least 5 structurally unique subfamilies, it is import- ant to determine how this complex family functions in neurons to regulate the intricate genetic programs of axon growth and regeneration. By characterizing the molecular mechanisms of the KlF family in the nervous system, including binding partners and gene targets, and comparing them to defined mechanisms defined outside the nervous system, we may better understand how KlFs regulate neurite growth and axon regeneration.

关键词： optic nerve regeneration axon growth retina retinal ganglion cells spinal cord transcription factors

Pain management strategies in penile implantation

在线全文

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2020年第1期22卷 34-38页

作者： jeffrey l Ellis Andrew M Higgins Jay Simhan Department of Urology Einstein Healthcare NetworkDivision of Urologic OncologyDepartment of Surgical OncologyFox Chase Cancer CenterPhiladelphiaPA 19141 USA

The opioid epidemic continues to be a serious public health *** have pointed to prescription drug misuse as a nidus for patients to become addicted to opioids and as such,urologists and other surgical subspecialists must critically define optimal pain management for the various procedures performed within their respective *** pain following penile prosthesis implantation remains a unique challenge for urologists,given the increased pain patients commonly experience in the postoperative *** most of the existing urological literature focuses on interventions performed in the operating room,there are many studies that examine the role of preoperative adjunctive pain medicine in diminishing postoperative narcotic *** are relatively few studies looking at postoperative strategies for managing pain in prosthetic surgery with follow-up past the immediate *** review assess the various strategies employed for managing pain following penile implantation through the lens of the current state of the opioid crisis,thus examining how urologists can responsibly treat pain without contributing to the growing threat of opioid addiction.

关键词： analgesia epidemic opioid pain prosthetic

Amplitude-mode spectroscopy of chemically injected and photogenerated charge carriers in semiconducting single-walled carbon nanotubes

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2023年第4期16卷 5619-5625页

作者： Shai R。Vardeny Alan Phillips Kira A。Thurman ZValy Vardeny jeffrey l.Blackburn Division of Electrical Electronicand Infocommunications EngineeringOsaka University2-1 Yamada-okaSuitaOsaka 565-0871Japan Materials Chemistryand Computation Science DirectorateNational Renewable Energy LaboratoryGoldenCO 80401USA Department of Physics Colorado School of MinesGoldenCO 80401USA Department of Physics&Astronomy University of UtahSalt Lake CityUT 84112USA

In one-dimensional semiconductors such as conjugated polymers and semiconducting single-walled carbon nanotubes(s-SWCNTs),injected charge carriers(electrons or holes)can have profound impacts on both electronic conductivity and optical spectra,even at low carrier *** charge-related spectral features is a key fundamental challenge with important technological ***,we employ a systematic suite of experimental and theoretical tools to understand the mid-infrared charge signatures of heavily p-type doped polymer-wrapped *** a broad range of nanotube diameters,we find that hole charge carriers induce strong Fano anti-resonances in mid-infrared transmission spectra that correspond to defect-related(D-band)and in-plane tangential(G-band)Raman-active vibrational modes,along with antiresonances arising from infrared(IR)-active polymer and SWCNT *** employ^(13)C isotope-labeled s-SWCNTs and a removable wrapping polymer to clarify the relative intensities,energies,and sources of all observed *** performed with the“amplitude mode model”are used to quantitatively reproduce Raman spectra and also help to explain the outsized intensity of the D-band anti-resonance,relative to the G-band,observed for both moderately and degenerately doped *** results provide a framework for future studies of ground-and excited-state charge carriers in s-SWCNTs and a variety of low-dimensional materials.

关键词： carbon nanotubes doping charge carriers phonons electron-phonon coupling

Transfusion trigger:how low can you go?

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中国输血杂志 2012年第10期25卷 917-918页

作者： jeffrey l.Carson UMDNJ-Robert Wood Johnson Medical School New BrunswickNew JerseyUSA

Approximately 12 million red blood cell (RBC)200 cc units are transfused annually in the China and about 85 million RBC units ***,there is widespread variation in transfusion practice.1,2 The most likely reason is that there has been limited high quality evidence to guide *** recent years there has been publication of several important clinical trials that expand the data informing the transfusion decision.

关键词：输血触发红血细胞临床试验 RBC 单位

Microenvironmental influences on T cell immunity in cancer and inflammation

在线全文

学校读者我要写书评

暂无评论

Cellular & Molecular Immunology 2022年第3期19卷 316-326页

作者： Darren R.Heintzman Emilie l.Fisher jeffrey C.Rathmell Department of Pathology Microbiologyand ImmunologyVanderbilt University Medical CenterNashvilleTN37205USA Vanderbilt Center for Immunobiology Vanderbilt University Medical CenterNashvilleTN37205USA

T cell metabolism is dynamic and highly *** the intrinsic metabolic programs of T cell subsets are integral to their distinct differentiation and functional patterns,the ability of cells to acquire nutrients and cope with hostile microenvironments can limit these pathways.T cells must function in a wide variety of tissue settings,and how T cells interpret these signals to maintain an appropriate metabolic program for their demands or if metabolic mechanisms of immune suppression restrain immunity is an area of growing *** in inflamed and cancer tissues,a wide range of changes in physical conditions and nutrient availability are now acknowledged to shape *** include fever and increased temperatures,depletion of critical micro and macro-nutrients,and accumulation of inhibitory waste *** we review several of these factors and how the tissue microenvironment both shapes and constrains immunity.

关键词： immunometabolism T cell microenvironment cancer inflammation