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Cloning and characterization of a FLORICAULA/LEAFY ortholog, PFL, in polygamous papaya

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Cell Research 2005年第8期15卷 576-584页

作者： Paul H. moore,Henrik H. albert,Adrienne H.K. ROADER,Ray MING USDA-ARS Pacific Basin Agricultural Research Center Aiea HI 96701 USA USDA-ARS Pacific Basin Agricultural Research Center Aiea HI 96701 USA Section of Cell and Developmental Biology University of California San Diego La Jolla CA 92093 USA Hawaii Agriculture Research Center Aiea HI 96701 USA

The homologous genes FLORICAULA (FLO) in Antirrhinum and LEAFY (LFY) in Arabidopsis are known to regu- late the initiation of flowering in these two distantly related plant species. These genes are necessary also for the expression of downstream genes that control floral organ identity. We used Arabidopsis LFY cDNA as a probe to clone and sequence a papaya ortholog of LFY, PFL. It encodes a protein that shares 61% identity with the Arabidopsis LFY gene and 71% identity with the LFY homologs of the two woody tree species: California sycamore (Platanus racemosa) and black cottonwood (Populus trichocarpa). Despite the high sequence similarity within two conserved regions, the N-terminal proline-rich motif in papaya PFL differs from other members in the family. This difference may not affect the gene function of papaya PFL, since an equally divergent but a functional LFY ortholog NEEDLY of Pinus radiata has been reported. Genomic and BAC Southern analyses indicated that there is only one copy of PFL in the papaya genome. In situ hybridization experiments demonstrated that PFL is expressed at a relatively low level in leaf primordia, but it is expressed at a high level in the floral meristem. Quantitative PCR analyses revealed that PFL was expressed in flower buds of all three sex types - male, female, and hermaphrodite with marginal difference between hermaphrodite and unisexual flowers. These data suggest that PFL may play a similar role as LFY in flower development and has limited effect on sex differentiation in papaya.

关键词： divergence floral meristem identity gene flower development gene expression molecular phylogeny.

Almost Global Strong Solutions to Quasilinear Dissipative Evolution Equations

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Chinese Annals of Mathematics,Series B 2009年第1期30卷 91-110页

作者： albert MILANI Department of Mathematics University of Wisconsin-Milwaukee

The author proves a global existence result for strong solutions to the quasilinear dissipative hyperbolic equation (1.1) below, corresponding to initial values and source terms of arbitrary size, provided that the hyperbolicity parameter ε is sufficiently small. This implies a corresponding global existence result for the reduced quasilinear parabolic equation (1.4) below.

关键词： Quasilinear evolution equation A priori estimates Global existence Small parameter

Difficult treatment decisions in autoimmune hepatitis

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World Journal of Gastroenterology 2010年第8期16卷 934-947页

作者： albert J Czaja Division of Gastroenterology and Hepatology Mayo Clinic College of Medicine

Treatment decisions in autoimmune hepatitis are complicated by the diversity of its clinical presentations,uncertainties about its natural history,evolving opinions regarding treatment end points,varied nature of refractory disease,and plethora of alternative immu-nosuppressive agents. The goals of this article are to review the difficult treatment decisions and to provide the bases for making sound therapeutic judgments. The English literature on the treatment problems in au-toimmune hepatitis were identifi ed by Medline search up to October 2009 and 32 years of personal experi-ence. Autoimmune hepatitis may have an acute severe presentation,mild in? ammatory activity,lack autoan-tibodies,exhibit atypical histological changes (centri-lobular zone 3 necrosis or bile duct injury),or have variant features reminiscent of another disease (overlap syndrome). Corticosteroid therapy must be instituted early,applied despite the absence of symptoms,or modified in an individualized fashion. Pursuit of normal liver tests and tissue is the ideal treatment end point,but this objective must be tempered against the risk of side effects. Relapse after treatment withdrawal requires long-term maintenance therapy,preferably with azathioprine. Treatment failure or an incomplete response warrants salvage therapy that can include conventional medications in modified dose or empiricaltherapies with calcineurin inhibitors or mycophenolate mofetil. Liver transplantation supersedes empirical drug therapy in decompensated patients. Elderly and pregnant patients warrant treatment modifications. Difficult treatment decisions in autoimmune hepatitis can be simplified by recognizing its diverse manifestations and individualizing treatment,pursuing realistic goals,applying appropriate salvage regimens,and identifying problematic patients early.

关键词： Autoimmune hepatitis Fulminant hepatitis Salvage therapy Treatment end points

Pedestrian walking speed at un-signalized midblock crosswalk and its impact on urban street segment performance

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Journal of Traffic and Transportation Engineering(English Edition) 2021年第1期8卷 57-69页

作者： albert Forde Janice Daniel Division of Statewide Planning New Jersey Department of TransportationTrentonNJ 08625USA Department of Civil and Environmental Engineering New Jersey Institute of TechnologyNewarkNJ 07102USA

The Urban Street Segment Chapter of the Highway Capacity Manual(HCM)includes a methodology for evaluating the level of service urban street segments provide to automobile *** methodology does not account for pedestrian activity at un-signalized midblock crosswalk on an urban street *** activity at un-signalized midblock crosswalk on urban street segments causes friction conditions between automobiles and *** a consequence,the average time it takes vehicles to travel along the segment is *** segment running time decreases both the travel speed of automobiles and the level of service provided to automobile *** is an inverse relationship between the delay incurred by interrupted vehicles and the speeds at which pedestrians walk while crossing at *** account for this delay,there is a need to investigate pedestrian walking speeds at un-signalized midblock *** study measured pedestrian walking speeds by age-group at two un-signalized midblock crosswalks on urban street *** first objective of this paper is to perform statistical analyses to examine the measured free-flow pedestrian walking *** second objective is to demonstrate how the findings of this study can be incorporated into the Urban Street Segment Analysis Chapter of the *** walking speeds were recorded and analyzed for 2937 *** results show teenagers walk at an average speed of 1.45 m/s,young adults walk at an average speed of 1.55 m/s,middle age pedestrians walk at a speed of 1.45 m/s,older pedestrians walk at speed of 1.09 m/s,and elderly or physically disabled pedestrians walk at a speed of 1.04 m/s.

关键词： Midblock Pedestrian Walking speed HCM Urban Street

Elevated 5-hydroxymethycytosine and cell apoptosis induced by tetrachloro-1,4-benzoquinone in mouse embryonic stem cells

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Journal of Environmental Sciences 2017年第1期29卷 1-4页

作者： albert Zuehlke Hongquan Zhang Division of Analytical and Environmental Toxicology Department of Laboratory Medicine and PathologyUniversity of AlbertaEdmontonAlbertaT6G 2G3Canada

Pentachlorophenol（PCP）has been extensively used as a fungicide,bactericide,herbicide,*** and insecticide worldwide（Ahlborg and Thunberg,1980：Choudhury et al.,1986）.Although PCP is primarily used as a preservative for wood and wood products,it has been also used in a variety of other products,including adhesives,construction materials,leather and paper.

关键词： Tetrachloro-1 4-benzoquinone (TCBQ) DNA methylation 5-hydroxymethylcytosine(5hmC) Apoptosis Stem cells

Regulation of expression of drug-metabolizing enzymes by oncogenic signaling pathways in liver tumors: a review

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Acta Pharmaceutica Sinica B 2020年第1期10卷 113-122页

作者： albert Braeuning Michael Schwarz German Federal Institute for Risk Assessment Dept.Food SafetyBerlin 10589Germany Eberhard Karls University of Tu¨bingen Inst.of Pharmacology and ToxicologyDept.of ToxicologyTu¨bingen 72074Germany

Mutations in genes encoding key players in oncogenic signaling pathways trigger specific downstream gene expression profiles in the respective tumor cell *** regulation of genes related to cell growth,survival,and death has been extensively studied,much less is known on the regulation of drug-metabolizing enzymes(DMEs)by oncogenic ***,a comprehensive review of the available literature is presented summarizing the impact of the most relevant genetic alterations in human and rodent liver tumors on the expression of DMEs with a focus on phasesⅠandⅡof xenobiotic *** few data are available with respect to DME regulation by p53-dependent signaling,telomerase expression or altered chromatin *** contrast,DME regulation by constitutive activation of oncogenic signaling via the RAS/RAF/mitogen-activated protein kinase(MAPK)cascade or via the canonical WNT/β-catenin signaling pathway has been analyzed in greater depth,demonstrating mostly positive-regulatory effects of WNT/β-catenin signaling and negativeregulatory effects of MAPK *** studies have revealed molecular interactions between oncogenic signaling and nuclear xeno-sensing receptors which underlie the observed alterations in DME expression in liver *** of altered DME expression and inducibility in liver tumors with a specific gene expression profile may impact pharmacological treatment options.

关键词： Xenobiotic metabolism Hepatocytes WNT/b-catenin signaling RAS/MAPK signaling Gene mutation Cytochrome P450

ON THE DIFFUSION PHENOMENON OF QUASILINEAR HYPERBOLIC WAVES

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Chinese Annals of Mathematics,Series B 2000年第1期21卷 63-70页

作者： YANG HAN albert MILANI Department of Applied Mathematics South West Jiaotong University610031 ChengduChina Department of Mathematics University of Wisconsin—M ilwaukeeMilwaukeeWisconsin 53201USA

The authors consider the asymptotic behavior of solutions of the quasilinear hyperbolic equation with linear damping u_(tt)+u_(t)-div(a(u)u)=0,and show that,at least when n≥3,they tend,as t-+∞,to those of the nonlinear parabolic equation v_t-div(a(v)v)=0,in the sense that the norm||u(.,t)-v(.,t)||_(L∞(R^n))of the difference u-v decays faster than that of either u or *** provides another example of the diffusion phenomenon of nonlinear hyperbolic waves,first observed by Hsiao,*** Liu Taiping(see[1,2]).

关键词： Asymptotic behavior of solutions Quasilinear hyperbolic and parabolic equations Diffusion phenomenon

Old and new concepts based on coherent structures for understanding sediment transport

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International Journal of Sediment Research 2011年第3期26卷 376-384页

作者： albert GYR Inst.of Hydromechanics and Water Resources Management Swiss Federal Institute of TechnologyCH-8093Swiss

Coherent structures develop due to an instability process on smooth beds under turbulent flow conditions and they are relevant for the incipient motion of fine sand *** flow structures were found to be relevant for the sediment transport under rough wall conditions,but an instability process could not explain *** this article we show that rough walls produce a new class of A-vortices,these vortices develop from separations on the grains,and are new relevant flow structures.

关键词： Sediment transport Incipient motion Coherent structures Turbulence Separations

Co-design of ESD protection and UWB RF front-end ICs

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Science China(Information Sciences) 2011年第10期54卷 2209-2220页

作者： WANG albert Department of Electrical Engineering University of CaliforniaRiverside 92521USA

This paper discusses critical aspects for co-design of ultra wideband (UWB) system-on-chip (SoC) and on-chip electrostatic discharge (ESD) protection,which are beyond the considerations on data rate and *** radio UWB system architecture has been defined with critical building blocks proposed and verified,including pulse generator,transmitter,low noise amplifier (LNA) and multiplier based *** protection is well considered for each related *** examples have been implemented in a commercial RFCMOS processes to demonstrate the working principles for key UWB transmitter and receiver circuit ***-ESD co-design techniques,simulation and measurement results for these UWB RF modules are presented in detail.

关键词： UWB impulse radio pulse generator BPSK modulation transmitter LNA multiplier correlator ESD protection co-design