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Neuroscience Bulletin 2015年第6期31卷 705-713页

作者： Arun Singh Claire A.Gutekunst Subramaniam Uthayathas john p.m.finberg Klaus mewes Robert E. Gross Stella m.papa Yair Feld Neuropharmacology and Neurologic Diseases Yerkes National Primate Research Center Department of Neurosurgery Emory University School of Medicine molecular pharmacology Department Rappaport Faculty of Medicine Department of Neurology Emory University School of Medicine Gene Grafts Ltd

Recent studies have shown that fibroblast transplantation can modify the activity of basal ganglia networks in models of parkinson＇s disease. To determine its effects on parkinsonian motor symptoms, we performed autologous dermal fibroblast transplantation into the internal pallidum （Gpi） in two parkinsonian rhesus monkeys with stable levodopa- induced dyskinesias （LIDs）. Levodopa responses were assessed every week after transplantation for three months. A reduction of between 58% and 64% in total LIDs on the contralateral side was observed in both animals. No clear LID changes were observed on the ipsilateral side. These effects lasted the entire 3-month period in one monkey, but declined after 6-8 weeks in the other. The antiparkinsonian effects of levodopa did not diminish, The results of this pilot study indicate that fibroblast transplantation into the Gpi may have beneficial effects on LIDs and warrant further investigation for potential therapeutic use.

关键词： globus pallidum autologous levodopa antiparkinsonian monkeys

Hepatic tight junctions:From viral entry to cancer metastasis

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World Journal of Gastroenterology 2010年第3期16卷 289-295页

作者： Nikki p Lee john m Luk Department of Surgery Queen Mary Hospital Department of pharmacology and Department of Surgery National University Health SystemNational University of Singapore

The tight junction (TJ) is a critical cellular component for maintenance of tissue integrity, cellular interactions and cell-cell communications, and physiologically functions as the "great wall" against external agents and the surrounding hostile environment. During the host-pathogen evolution, viruses somehow found the key to unlock the gate for their entry into cells and to exploit and exhaust the host cells. In the liver, an array of TJ molecules is localized along the bile canaliculi forming the blood-biliary barrier, where they play pivotal roles in paracellular permeability, bile secretion, and cell polarity. In pathology, certain hepatic TJ molecules mediate virus entry causing hepatitis infection; deregulation and functional abnormality of the TJ have also been implicated in triggering liver cancer development and metastasis. All these findings shed new insights on the understanding of hepatic TJs in the development of liver disease and provide new clues for potential intervention.

关键词： Tight junctions Hepatocytes Blood-biliary barrier Bile canaliculi Hepatitis Liver steatosis Liver neoplasms

predation changes the shape of thermal performance curves for population growth rate

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Current Zoology 2016年第5期62卷 501-505页

作者： Thomas m. LUHRING john p. DELONG School of Biological Sciences University of Nebraska Lincoln Nebraska 68588 USA

Ectotherms generally demonstrate nonlinear changes in performance （e.g., movement speed, indi- vidual growth, population growth） as a function of temperature that are characterized by thermal performance curves （TpC）. predation risk elicits phenotypic and behavioral changes that likewise impact performance measures. We tested whether exposure to predation Orthocyclops modestus impacts the maximum population growth rate （rmax） TpC of the protist paramecium aurelia. We fit predator and non-predator exposed p. aurelia population growth rates to a function previously shown to best describe paramecium population growth rate TpC＇s （Lactin-2） and compared subse- quent parameter estimates between curves. For paramecium exposed to predation risk, maximum population growth increased more rapidly as temperatures rose and decreased more rapidly as temperatures fell compared to the initial temperature. The area under each TpC curve remained ap- proximately the same, consistent with the idea of a trade-off in performance across temperatures. Our results indicate TpCs are flexible given variation in food web context and that trophic inter- actions may play an important role in shaping TpCs. Furthermore, this and other studies illustrate the need for a mechanistic model of TpCs with parameters tied to biologically meaningful properties.

关键词： paramecium phenotypic plasticity predation reaction norm temperature thermal performance curve.

LIQUID CRYSTAL BASED ROTATING ORTHOGONAL pOLARIZATION ImAGING SYSTEm

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Journal of Innovative Optical Health Sciences 2009年第3期2卷 245-251页

作者： QUN ZHU IAN m.STOCKFORD john A.CROWE STEpHEN p.mORGAN School of Electrical and Electronic Engineering University of Nottingham University Park NottinghamUK NG72RD

Rotating orthogonal polarization imaging provides images of the polarization properties of scattering media which are free from surface *** the technique has been demonstrated using manually rotated Glan–Thompson polarizers to control and analyze the polarization state of the light entering and emerging from the *** paper describes a system that performs these functions using liquid crystal *** system is tested using a polarizing target embedded within a scattering medium and is compared with monte Carlo *** results compare well with those obtained with manual rotation of *** liquid crystal based approach has advantages over the previous system in terms of ease of use,speed,and repeatability and is therefore an important step towards taking the technique into routine clinical use.

关键词： Liquid crystal polarization orthogonal surface reflection scattering tissue.

Chebyshev Spectral methods and the Lane-Emden problem

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Numerical mathematics(Theory,methods and Applications) 2011年第2期4卷 142-157页

作者： john p.Boyd Department of Atmospheric Oceanic and Space ScienceUniversity of Michigan2455 Hayward AvenueAnn ArborMI 48109-2143USA

The three-dimensional spherical polytropic Lane-Emden problem is yr r+(2/r)y_(r)+y^(m)=0,y(0)=1,y_(r)(0)=0 where m∈[0,5]is a constant *** domain is r∈[0,ξ]whereξis the first root of y(r).We recast this as a nonlinear eigenproblem,with three boundary conditions andξas the eigenvalue allowing imposition of the extra boundary condition,by making the change of coordinate x≡r/ξ:y_(xx)+(2/x)y_(x)+ξ^(2) y^(m)=0,y(0)=1,y_(x)(0)=0,y(1)=*** find that a Newton-Kantorovich iteration always converges from an m-independent starting point y^((0))(x)=cos([π/2]x),ξ^((0))=*** apply a Chebyshev pseudospectral method to discretize *** Lane-Emden equation has branch point singularities at the endpoint x=1 whenever m is not an integer;we show that the Chebyshev coefficients are a_(n)∼constant/n^(2m+5) as n→∞.However,a Chebyshev truncation of N=100 always gives at least ten decimal places of accuracy—much more accuracy when m is an *** numerical algorithm is so simple that the complete code(in maple)is given as a one page table.

关键词： Lane-Emden Chebyshev polynomial pseudospectral

A Fourier Companion matrix (multiplication matrix) with Real-Valued Elements: Finding the Roots of a Trigonometric polynomial by matrix Eigensolving

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Numerical mathematics(Theory,methods and Applications) 2013年第4期6卷 586-599页

作者： john p.Boyd Department of Atmospheric Oceanic&Space ScienceUniversity of Michigan2455 Hayward AvenueAnn Arbor MI 48109USA

We show that the zeros of a trigonometric polynomial of degree N with the usual(2N+1)terms can be calculated by computing the eigenvalues of a matrix of dimension 2N with real-valued elements m_(jk).This matrix m is a multiplication matrix in the sense that,after first defining a vector φwhose elements are the first 2N basis functions,mφ=2cos(t)φ.This relationship is the eigenproblem;the zeros tk are the arccosine function of λ_(k)/2 where theλk are the eigenvalues of *** dub this the“Fourier Division Companion matrix”,or FDCm for short,because it is derived using trigonometric polynomial *** show through examples that the algorithm computes both real and complex-valued roots,even double roots,to near machine precision accuracy.

关键词： Fourier series trigonometric polynomial rootfinding secular companion matrix

Human-tiger conflict:A review and call for comprehensive plans

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Integrative Zoology 2010年第4期5卷 300-312页

作者： john m.GOODRICH Wildlife Conservation Society BronxNew YorkNYUSA

Human-tiger(panthera tigris Linnaeus,1758)conflicts(HTC),manifested primarily as attacks on people and domestic animals,exacerbate at least 2 major threats to tigers:(i)conflicts often result in mortality or removal of tigers from the wild;and(ii)they result in negative attitudes towards tigers by local people,thereby reducing support for tiger *** HTC has decreased over the past century,it will likely increase if current and proposed conservation initiatives to double tiger populations are *** HTC could undermine successful conservation initiatives if proactive steps are not taken to reduce *** present paper provides a review of the impacts of HTC and the measures taken to reduce it in ways that reduce negative impacts on both humans and tigers,and stresses the need for development and implementation of comprehensive plans to reduce HTC.

关键词： carnivore depredation human-tiger conflict panthera tigris tiger

Reliability-based design in rock engineering: Application of Bayesian regression methods to rock strength data

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Journal of Rock mechanics and Geotechnical Engineering 2019年第3期11卷 612-627页

作者： Nezam Bozorgzadeh john p.Harrison Department of Civil Engineering GeoEngineering Centre at Queen’s-RMC(Royal Military College of Canada)KingstonCanada Department of Civil and mineral Engineering University of TorontoTorontoCanada

Reliability-based design (RBD) is being adopted by geotechnical design codes worldwide, and it is therefore necessary that rock engineering practice evolves to embrace RBD. This paper examines the Hoek-Brown (H-B) strength criterion within the RBD framework, and presents three distinct analyses using a Bayesian approach. Firstly, a compilation of intact compressive strength test data for six rock types is used to examine uncertainty and variability in the estimated H-B parameters m and σc, and corresponding predicted axial strength. The results suggest that within- and between-rock type variabilities are so large that these parameters need to be determined from rock testing campaigns, rather than reference values being used. The second analysis uses an extensive set of compressive and tensile (both direct and indirect) strength data for a granodiorite, together with a new Bayesian regression model, to develop joint probability distributions of m and σc suitable for use in RBD. This analysis also shows how compressive and indirect tensile strength data may be robustly used to fit an H-B criterion. The third analysis uses the granodiorite data to investigate the important matter of developing characteristic strength criteria. Using definitions from Eurocode 7, a formal Bayesian interpretation of characteristic strength is proposed and used to analyse strength data to generate a characteristic criterion. These criteria are presented in terms of characteristic parameters mk and σck, the values of which are shown to depend on the testing regime used to obtain the strength data. The paper confirms that careful use of appropriate Bayesian statistical analysis allows the H-B criterion to be brought within the framework of RBD. It also reveals that testing guidelines such as the International Society for Rock mechanics and Rock Engineering (ISRm) suggested methods will require modification in order to support RBD. Importantly, the need to fully understand the implications of

关键词： Reliability-based design(RBD) Hoek-Brown(HeB)criterion Bayesian regression Indirect tensile strength Characteristic strength criterion

Fusion of bone marrow-derived cells with cancer cells: metastasis as a secondary disease in cancer

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Chinese Journal of Cancer 2014年第3期33卷 133-139页

作者： john m.pawelek Department of Dermatology and the Yale Cancer Center Yale University School of Medicine

This perspective article highlights the leukocyte-cancer cell hybrid theory as a mechanism for cancer metastasis. Beginning from the first proposal of the theory more than a century ago and continuing today with the first proof for this theory in a human cancer, the hybrid theory offers a unifying explanation for metastasis. In this scenario, leukocyte fusion with a cancer cell is a secondary disease superimposed upon the early tumor, giving birth to a new, malignant cell with a leukocyte-cancer cell hybrid epigenome.

关键词： Bone marrow-derived cell-cancer cell hybrids metastasis cell fusion

Hepatic artery stenosis angioplasty and implantation of Wingspan neurovascular stent: A case report and discussion of stenting in tortuous vessels

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World Journal of Gastroenterology 2020年第4期26卷 448-455页

作者： mark Barahman Lourdes Alanis Joseph DiNorcia john m moriarty Justin p mcWilliams Department of pathology Albert Einstein College of Medicine and Montefiore Medical CenterBronxNY 10461United States Department of Radiology Division of Interventional RadiologyRonald Reagan Medical Center at UCLADavid Geffen School of Medicine at UCLALos AngelesCA 90095United States Division of Interventional Radiology Ronald Reagan Medical Center at UCLADavid Geffen School of Medicine at UCLALos AngelesCA 90095United States Department of Surgery Ronald Reagan Medical Center at UCLADavid Geffen School of Medicine at UCLALos AngelesCA 90095United States

BACKGROUND Hepatic artery stenosis is a complication of orthotopic liver transplant occurring in 3.1%-7.4%of patients that can result in graft failure and need for *** therapy with angioplasty and stenting has been used with a high degree of technical success and good clinical outcomes,but tortuous hepatic arteries present a unique challenge for *** stents for this application should be maneuverable and conformable while also exerting adequate radial force to maintain a patent *** SUmmARY Herein we report our experience with a neurovascular Wingspan stent system in a challenging case of recurrent hepatic artery stenosis and discuss the literature of stenting in tortuous transplant hepatic *** Wingspan neurovascular stent is self-expanding,has good conformability,and adequate radial resistance and as such it could be added to the armamentarium of interventionalists in the setting of a tortuous and stenotic transplant hepatic artery.

关键词： Hepatic artery stenosis Case report Endovascular Angioplasty Stent Wingspan neurointerventional stent