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Can a multistage approach improve individual tree mortality predictions across the complex mixed-species and managed forests of eastern North America?

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Forest Ecosystems 2023年第1期10卷 21-30页

作者： Cen Chen John Kershaw Jr Aaron Weiskittel elizabeth McGarrigle Center for Research on Sustainable Forests University of MaineOronoME04469USA Faculty of Forestry&Environmental Management University of New BrunswickFrederictonNBE3B 5A3Canada Nova Scotia Department of Natural Resources HalifaxNSB3J 3M8Canada

Tree mortality plays a fundamental role in the dynamics of forest ecosystems,yet it is one of the most difficult phenomena to accurately *** modeling strategies have been developed to improve individual tree mortality *** less explored strategy is the use of a multistage modeling *** improvements from this approach have remained largely *** this study,we developed a novel multistage approach and compared its performance in individual tree mortality predictions with a more conventional approach using an identical individual tree mortality model *** permanent plot data(n=9442)covering the Acadian Region of North America and over multiple decades(1965–2014)were used in this *** results indicated that the model behavior with the multistage approach better depicted the observed mortality and showed a notable improvement over the conventional *** difference between the observed and predicted numbers of dead trees using the multistage approach was much smaller when compared with the conventional *** addition,tree survival probabilities predicted by the multistage approach generally were not significantly different from the observations,whereas the conventional approach consistently underestimated mortality across species and overestimated tree survival probabilities over the large range of DBH in the *** new multistage approach also predictions of zero mortality in individual plots,a result not possible in conventional ***,the new approach was more tolerant of modeling errors because it based estimates on ranked tree mortality rather than error-prone predicted ***,this new multistage approach deserves to be considered and tested in future studies.

关键词： Tree mortality modeling Mortality disaggregation Mixed effect model Annualization Mixed forests

Operable gastro-oesophageal junctional adenocarcinoma: Where to next?

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World Journal of Gastrointestinal Oncology 2014年第6期6卷 145-155页

作者： elizabeth C Smyth David Cunningham Department of Gastrointestinal Oncology Royal Marsden Hospital

Oesophageal junctional adenocarcinoma is a challeng-ing and increasingly common disease. Optimisation ofpre-operative staging and consolidation of surgery inlarge volume centres have improved outcomes, howev-er the preferred adjunctive treatment approach remainsa matter of debate. This review examines the benefitsof neoadjuvant, peri-operative, and post-operative che-motherapy and chemoradiotherapy in this setting in anattempt to reach an evidence based conclusion. Recentfindings relating to the molecular characterisation ofoesophagogastric cancer and their impact on therapeu-tics are explored, in addition to the potential benefitsof fluoro-deoxyglucose positron emission tomography(FDG-PET) directed therapy. Finally, efforts to decreasethe incidence of junctional adenocarcinoma using earlyintervention in Barrett's oesophagus are discussed,including the roles of screening, endoscopic mucosalresection, ablative therapies and chemoprevention.

关键词： Oesophageal adenocarcinoma Junctional adenocarcinoma Gastric adenocarcinoma Peri-operative chemotherapy Pre-operative chemoradiotherapy Molecular profiling Fluoro-deoxyglucose-positron emission tomography Barrett's oesophagus Chemoprevention

Emerging molecular targets and therapy for cholangiocarcinoma

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World Journal of Gastrointestinal Oncology 2017年第7期9卷 268-280页

作者： Hamzeh Kayhanian elizabeth C Smyth Chiara Braconi Department of Gastrointestinal Oncology Royal Marsden Hospital London and Surrey SM2 5PT Institute of Cancer Research London and Surrey SM2 5PT

Cholangiocarcinoma(CCA) is a rare cancer arising from the biliary tree with a poor prognosis and limited therapeutic options. Recent large scale molecular characterisation studies have identified recurrent genetic alterations in CCA which may be amenable to therapeutic targeting. In this review we explore the genomic landscape of CCA and examine results from trials of molecularly targeted agents and immunotherapy in this disease. Challenges in CCA diagnosis, treatment and trial design are discussed and we reflect on future directions which may lead to improved outcomes for CCA patients.

关键词： Cholangiocarcinoma Biliary tract cancer Targeted therapy immunotherapy Mutation Molecular Microenvironment Stroma MiRNA

Adult neural stem cell plasticity

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Neural Regeneration Research 2019年第2期14卷 256-257页

作者： elizabeth J.Sandquist Donald S.Sakaguchi Department of Zoology Weber State University Department of Genetics Development and Cell Biology Iowa State University Neuroscience Program Iowa State University Nanovaccine Institute Iowa State University

Stem cells derived from adult tissues have long been consideredmultipotent, able to differentiate into a limited number of cell typesfound in their tissue of origin. Embryonic stem cells, in contrast,are pluripotent, which may differentiate into almost all cell *** the ability to create induced pluripotent stem cells from somaticcells now available, the properties of multipotent stem cellsare being re-evaluated. If adult cells may be reverted to pluripotentstem cells, can multipotent stem cells also be manipulated towardspluripotency? Advancements in biotechnology now allow for bettermethods to investigate stem cell plasticity, such as the relativeinfluence of external versus intrinsic factors on cell fate. Recentstudies indicate that adult neural stem cells (NSCs) demonstrategreater plasticity under certain conditions, resulting in the derivationof a variety of cell types including muscle, hematopoietic, andepithelial cells. This suggests that NSCs may provide a potentialsource of rare cell types for clinical application as an alternative toembryonic stem cells. Producing rare cell types from NSCs ratherthan embryonic stem cells avoids the ethical issues surrounding theuse of this cell type. Further, NSCs may be an advantageous sourcecompared to induced pluripotent stem cells, which are difficult tocreate, expensive, and time-consuming to

关键词： cells stem cell NSCs types

Hybrid solar cells constructed of macroporous n-type GaP coated with PEDOT:PSS

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Chinese Chemical Letters 2015年第4期26卷 469-473页

作者： Zhijie Wang elizabeth S.Brown Stephen Maldonado Department of Chemistry University of Michigan Program in Applied Physics University of Michigan

Hybrid organic-inorganic solar cell devices were fabricated utilizing macroporous n-type GaP and poly（3,4-ethylenedioxythiophene）：poly（4-styrene sulfonate）（PEDOT：PSS）. The high-aspect ratio structures of the macroporous GaP resulted in higher photocurrent and external quantum yield as a function of wavelength. Photocurrent-voltage measurements as a function of light intensity revealed information on the dependence of short-circuit current （Jsc） and open-circuit voltage （Voc） on light intensity. Under 1.0 Sun illumination, hybrid macroporous GaPJPEDOT：PSS devices showed Jsc of 2.34 mA cm 2, Voc of 0.95 V, fill factor of 0.54, and overall efficiency of 1.21%. The extent of the influence of dopant density of GaP on hybrid device performance was probed with current density-voltage measurements. The addition of a gold nanoparticle coating on macroporous GaP prior to PEDOT：PSS coating showed increased device performance, with overall efficiency of 1.81%. Gold-modified planar GaPJPEDOT：PSS showed decreased Jsc and Voc values and lower external quantum yield over all wavelengths,

关键词： Gallium phosphideOrganic-inorganic solar cellMacroporous

VOLUME SEGMENTATION BY POST-PROCESSING DATA FROM SIMULATION OF SOLIDIFICATION IN THE METAL CASTING PROCESS

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International Journal of Modeling, Simulation, and Scientific Computing 2013年第S01期4卷 128-141页

作者： elizabeth JACOB M.MANOJ ROSCHEN SASIKUMAR Computational Modeling and Simulation Unit National Institute for Interdisciplinary Science and Technology Council of Scientific and Industrial Research Trivandrum–695019 India

In the process of interpreting simulation results,new post-processing techniques are *** work presents a post-processing method that analyzes the solidification pattern formed by simulation of the solidification process of molten metal in a mold to produce shaped *** generally involve numerical solutions of differential equations which are discretized by dividing the three-dimensional computational domain into small finite volume elements using a 3D *** locations of the grid points and values of the solidification time at these locations are used to divide the spatial data into 3D sections such that starting from a hotspot location within the section that has high solidification time,there is a gradient outwards with lower values of solidification *** section is assumed to be fed by one or more feeders that must freeze only after the section has solidified *** volume of a feeder can be determined from the volume of the section it is supposed to *** volume and surface area of sections are determined approximately to calculate feeder size and *** post-processing algorithm is a simulation-based quantitative approach to feeder design which in conventional foundry practice has been more of an art than *** is also general enough for use in other 3D segmentation applications.

关键词： Metal casting simulation solidification pattern volume segmentation feeder design.

Optimal load frequency control through combined state and control gain estimation for noisy measurements

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Protection and Control of Modern Power Systems 2020年第1期5卷 268-279页

作者： Anju G.Pillai elizabeth Rita Samuel A.Unnikrishnan Department of Electrical&Electronics Engineering Rajagiri School of Engineering&TechnologyErnakulamKerala 682037India APJ Abdul Kalam Technological University ThiruvananthapuramKeralaIndia

Combined estimation of state and feed-back gain for optimal load frequency control is *** frequency control(LFC)addresses the problem of controlling system frequency in response to disturbance,and is one of main research areas in power system operation.A well acknowledged solution to this problem is feedback stabilization,where the Linear Quadratic Regulator(LQR)based controller computes the feedback gain K from the known system parameters and implements the control,assuming the availability of all the state ***,this approach restricts control to cases where the state variables are readily available and the system parameters are ***,by estimating the states continuously from available measurements of some of the states,it can accommodate dynamic changes in the system *** paper proposes the technique of augmenting the state variables with controller *** introduces a non-linearity to the augmented system and thereby the estimation is performed using an Extended Kalman *** results in producing controller gains that are capable of controlling the system in response to changes in load demand,system parameter variation and measurement noise.

关键词： Load frequency control State feedback control Linear quadratic regulator Extended Kalman filter Single area power system

Discussion of some‘knowns’and some‘unknowns’about the tumour suppressor p53

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Journal of Molecular Cell Biology 2019年第3期11卷 212-223页

作者： elizabeth Lieschke Zilu Wang Gemma L Kelly Andreas Strasser The Walter and Eliza Hall Institute of Medical Research Melbourne 3052Australia Department of Medical Biology University of MelbourneMelbourne 3050Australia

Activation of the tumour suppressor p53 upon cellular stress can induce a number of different cellular processes?The diverse actions of these processes are critical for the protective function of p53 in preventing the development of ***,it is still not fully understood which process(es)activated by p53 is/are critical for tumour suppression and how this might differ depending on the type of cells undergoing neoplastic transformstion and the nature of the drivers of ***,it is not clear why upon activation of p53 some cells undergo cell cycle arrest and senescence whereas others die by *** we discuss some of the cellular processes that are crucial for p53-mediated tumour suppression and the factors that could impact cell fate upon p53 ***,we describe therapies aimed either at activating wild-type p53 or at changing the behaviour of mutant p53 to unleash tumour growth suppressive processes for therapeutic benefit in malignant disease.

关键词： p53 tumour suppression cell death cell cycle arrest/senescenee

Continued surprises in the cytochrome c biogenesis story

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Protein & Cell 2012年第6期3卷 405-409页

作者： elizabeth B.Sawyer Paul D.Barker National Laboratory of Biomacromolecules Institute of BiophysicsChinese Academy of SciencesBeijing 100101China University Chemical Laboratory University of CambridgeCambridgeCB21EWUnited Kingdom

Cytochromes c covalently bind their heme prosthetic groups through thioether bonds between the vinyl groups of the heme and the thiols of a CXXCH motif within the *** Gramnegative bacteria,this process is catalyzed by the Ccm(cytochrome c maturation)proteins,also called System *** Ccm proteins are found in the bacterial inner membrane,but some(CcmE,CcmG,CcmH,and CcmI)also have soluble functional domains on the periplasmic face of the *** of the mechanisms involved in the transport and relay of heme and the apo-cytochrome from the bacterial cytosol into the periplasm,and their subsequent reaction,has proved challenging due to the fact that most of the proteins involved are membrane-associated,but recent progress in understanding some key components has thrown up some *** this Review,we discuss advances in our understanding of this process arising from a substrate’s point of view and from recent structural information about individual components.

关键词： cytochrome c heme Ccm post-transla-tional modification cytochrome b562 heme binding