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The functional significance of dentin sialoprotein-phosphophoryn and dentin sialoprotein

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International Journal of Oral Science 2018年第4期10卷 197-202页

作者： helena Ritchie Department of Cariology Restorative Sciences and EndodonticsUniversity of Michigan School of Dentistry

Phosphophoryn (PP) and dentin sialoprotein (DSP) are the most dominant non-collagenous proteins in dentin. PP is an extremely acidic protein that can function as a mineral nucleator for dentin mineralization. DSP was first identified in 1981, yet its functional significance is still controversial. Historically, these two proteins were considered to be independently synthesized and secreted by dental pulp cells into the developing dentin matrix. However, with the identification of the DSP coding sequence in 1994, followed2 years later by the finding that the PP coding sequence was located immediately downstream from the DSP sequence, it became immediately clear that DSP and PP proteins were derived from a single DSP-PP (i.e., dentin sialophosphoprotein, DSPP) *** DSPP cDNA became available, tremendous progress has been made in studying DSP-PP mRNA distribution and DSP generation from the DSP-PP precursor protein at specific cleavage sites by protease tolloid-related-1 (TLR1) or bone morphogenetic protein 1 (BMP1). The functions of DSP-PP and DSP were investigated via DSP-PP knockout (KO) and DSP knockin in DSP-PP KO mice. In addition, a number of in vitro studies aimed to elucidate DSPP and DSP function in dental pulp cells.

关键词： DSP The functional significance of dentin sialoprotein-phosphophoryn and dentin sialoprotein

Optimal plot design in a multipurpose forest inventory

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Forest Ecosystems 2016年第1期3卷 37-50页

作者： helena M.Henttonen Annika Kangas Natural Resources Institute Finland(Luke) Economics and Society unit

Background： We explore the factors affecting the optimal plot design （size and type as well as the subsample tree selection strategies within a plot） and their relative importance in defining the optimal plot design in amultipurpose forest inventory. The factors include time used to lay out the plot and to make the tree measurements within the plot, the between-plot variation of each of the variables of interest in the area, and the measurement and model errors for the different variables. Methods： We simulate different plot types and sizes and subsample tree selection strategies on measuredtest areas from North Lapland. The plot types used are fixed-radius, concentric and relascope plots. Weselect the optimal type and size first at plot level using a cost-plus-loss approach and then at cluster level byminimizing the weighted standard error with fixed budget. Results： As relascope plots are ve~/efficient at the plot level for volume and basal area, and fixed-radius plots for stems per ha, the optimal plot type strongly depends on the relative importance of these variables. The concentric plot seems to be a good compromise between these two in many cases. The subsample tree selection strategy was more important in selecting optimal plot than many other factors. In cluster level, the most important factor is the transfer time between plots. Conclusions： While the optimal radius of plots and other parameters were sensitive to the measurement times and other cost factors, the concentric plot type was optimal in almost all studied cases. Subsample tree measurement strategies need further studies, as they were an important cost factor. However, their importance to the precision was not as clear.

关键词： Sample Plot Forest inventory Measurement Cost Loss

A NEW APPROACH TO RECOVERY OF DISCONTINUOUS GALERKIN

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Journal of Computational Mathematics 2009年第6期27卷 697-712页

作者： Sebastian Franz Lutz Tobiska helena Zarin Institut für Numerische MathematikTechnische Universitt Dresden Institut für Analysis und NumerikOtto-von-Guericke Universitt Magdeburg Department of Mathematics and Informatics University of Novi SadTrg Dositeja Obradovica 421 000 Novi Sad

A new recovery operator P ：Qn^disc（T）→Qn＋1^disc（M） for discontinuous Galerkin is derived. It is based on the idea of projecting a discontinuous, piecewise polynomial solution on a given mesh T into a higher order polynomial space on a macro mesh M. In order to do so, we define local degrees of freedom using polynomial moments and provide global degrees of freedom on the macro mesh. We prove consistency with respect to the local L2-projection, stability results in several norms and optimal anisotropic error estimates. As an example, we apply this new recovery technique to a stabilized solution of a singularly perturbed convection-diffusion problem using bilinear elements.

关键词： Discontinuous Galerkin Postprocessing Recovery.

Physiology of gangliosides and the role of antiganglioside antibodies in human diseases

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Cellular & Molecular Immunology 2020年第4期17卷 313-322页

作者： Gianni Cutillo Anna-helena Saariaho Seppo Meri Translational Immunology Research Program and the Department of Bacteriology and Immunology University of HelsinkiHelsinkiFinland Humanitas University MilanRozzanoItaly Helsinki University Hospital Laboratory(HUSLAB) HelsinkiFinland

Gangliosides are structurally and functionally polymorphic sialic acid containing glycosphingolipids that are widely distributed in the human *** play important roles in protecting us against immune attacks,yet they can become targets for autoimmunity and act as receptors for microbes,like the influenza viruses,and toxins,such as the cholera *** expression patterns of gangliosides vary in different tissues,during different life periods,as well as in different *** against gangliosides(AGA)can target immune attack e.g.,against neuronal cells and neutralize their complement inhibitory *** are important especially in acquired demyelinating immune-mediated neuropathies,like Guillain–Barrésyndrome(GBS)and its variant,the Miller–Fisher syndrome(MFS).They can emerge in response to different microbial agents and immunological ***,they can be involved in a variety of *** addition,antibodies against GM3 were found in the sera of patients vaccinated with Pandemrix®,who developed secondary narcolepsy,strongly supporting the autoimmune etiology of the disease.

关键词： ganglioside Guillain-Barre syndrome complement narcolepsy sialic acid

Comparison of Classical Models for Evaluating the Heat Requirements of Olive(Olea europeae L.) in Portugal

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Journal of Integrative Plant Biology 2006年第6期48卷 664-671页

作者： helena Ribeiro Mário Cunha Ilda Abreu Autonomous Section of Agricultural Sciences Faculty of Sciences University of Porto4485-661 VairaoPortugal Department of Botany Faculty of SciencesUniversity of Porto1191-4150 PortoPortugal Institute of Agricultural Sciences and Technology 4485-661 VairaoPortugal Department of Botany Faculty of Sciences University of Porto1191-4150 PortoPortugal Institute for Molecular and Cell Biology 823-4150 PortoPortugal

The aim of the present study was to compare the accuracy and reproducibility of six statistical models for the calculation of olive （Olea europeae L.） heat requirements to trigger the onset of flowering in three Portuguese regions： Reguengos de Monsaraz, Valenga do Douro, and Braga. Other alms were to ascertain the date on which the heat-accumulation period started and the threshold temperatures above which the development of reproductive structures starts in olives. The starting and peak dates for the regional O. europeae flowering season were estimated by monitoring airborne pollen from 1998 to 2004 using ＂Cour＂- type samplers. The threshold temperature values calculated for the three regions were very similar （9.0 ℃ for Valenca do Douro, 9.2 ℃ for Reguengos de Monsaraz, and 9.7 ℃ for Braga）. The accumulated daily mean temperature model had less interannual and inter-regional variation, showing best predictive results for 2004, with absolute differences between the observed and predicted dates of 4 d in Reguengos de Monsaraz and 2 d In Valenca do Douro and Braga for the onset of flowering date and of 2 d In Reguengos de Monsaraz, 7 d in Valenca do Douro, and 4 d in Braga for peak flowering dates. This model was the most accurate, reproducible, and operational to calculate heat requirements for olives to flower, with an average mean temperature accumulation of 1 446 ℃ In Reguengos, 1 642 ℃ in Valenga do Douro, and 1 703℃ In Braga to reach the onset of flowering. The best initial date for this accumulation was 1 January.

关键词： flowering season heat requirements olives pollen Portugal

Quasiparticle approach to diffusional atomic scale self-assembly of complex structures: from disorder to complex crystals and double-helix polymers

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npj Computational Materials 2016年第1期2卷 256-264页

作者： Mykola Lavrskyi helena Zapolsky Armen G Khachaturyan GPM UMR 6634University of RouenSaint-Etienne du RouvrayFrance Department of Materials Science&Engineering Rutgers UniversityPiscatawayNJUSA Department of Materials Science&Engineering University of CaliforniaBerkeleyBerkeleyCAUSA

A self-organisation is an universal phenomenon in nature and,in particular,is highly important in materials *** goal was to develop a new theory that provides a computationally effective approach to this *** this paper a quasiparticle theory of a diffusional self-organisation of atoms in continuum space during the diffusional time scale has been *** became possible due to two novelties,a concept of quasiparticles,fratons,used for a description of dynamic degrees of freedom and model Hamiltonian taking into account a directionality,length and strength of interatomic *** illustrate a predictive power and achievable level of complexity of self-assembled structures,the challenging cases of self-assembling of the diamond,zinc-blende,helix and double-helix structures,from a random atomic distribution,have been successfully *** approach opens a way to model a self-assembling of complex atomic and molecular structures in the atomic scale during diffusional time.

关键词： diffusion helix particle

Urban Park Soil and Vegetation: Effects of Natural and Anthropogenic Factors

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Pedosphere 2015年第3期25卷 392-404页

作者： Pariente SARAH helena Michaela ZHEVELEV Atar OZ Laboratory of Geomorphology and Soil Department of Geography and EnvironmentBar-Ilan University

Various soil surface components, such as trees, shrubs and biological crusts, and human recreational activities, e.g., barbecues and trampling by visitors, may divide the area of the urban park into smaller fragments/mieroenvironments, differentiated by their microenvironmental conditions, which may differ in soil and vegetation characteristics. The spatial changes in the soil and vegetation characteristics and their causes were investigated in an urban park located south of Tel Aviv-Jaffa, Israel. The area of the park is 0.5 km^2, including groves, a lake, lawns, and rest areas. Soil was sampled in nine microenvironments, of which seven were within the park： under Ceratonia siliqua trees （CsU）, under Ficus sycomorus trees （FLU）, rest area between tables under F. sycomorus （FIB）, rest area under tables under F. sycomorus （FIT）, open area with bare soil （OaS）, open area with biological crust cover （OaC）, and open area covered by herbaceous vegetation （OaV）. Two more microenvironments, planar and sloping open areas （CoP and CoS, respectively） in the vicinity of the park, were used as the controls. Electrical conductivity, concentrations of soluble ions （Mg^2＋, Ca^2＋, Na^＋, K^＋ and HCO3）, pH, contents of organic carbon, calcium carbonate and moisture, and grain size distribution were determined. In addition, herbaceous vegetation cover, number and diversity of herbaceous vegetation species were measured. It was found that soil properties and herbaceous vegetation characteristics varied within the park. Soil organic carbon, electrical conductivity, soluble salts, penetration depth, and vegetation characteristics were affected by human activities, mainly in the rest area between the tables. In contrast, the above characteristics were affected by natural factors mainly in the rest of the microenvironments, which were subjected to low levels of anthropogenic intervention. The heterogeneous structure of the park, as represented by the various microenvironments, offered new

关键词： anthropogenic activity herbaceous vegetation microenvironment soil properties species diversity

Contributions of World Literatures in Portuguese to the Academic Field

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Journal of Foreign Languages and Cultures 2024年第1期8卷 48-54页

作者： helena BUESCU University of Lisbon

As one considers the concept of comparative world literature,one may ponder on how widening the perspective from an all-English area of studies to other languages promotes different worldviews and descriptions of the status *** this article,we take into consideration the perspective of literature written in Portuguese,be it European,Brazilian,African of even Asian,in order to demonstrate how rich such other points of view are for the *** also engage the concept of defamiliarization(ostranenie),proposed by Russian Formalist,Viktor Shklovsky,as a central tool to consider cosmopolitanism and the dialogue between different literatures.

关键词： comparative world literature literatures in Portuguese defamiliarization(ostranenie) textualism

Arbuscular mycorrhizal fungal community assembly in the Brazilian tropical seasonal dry forest

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Ecological Processes 2017年第1期6卷 9-18页

作者： Tancredo Augusto Feitosa de Souza helena Freitas Centre for Functional Ecology Department of Life SciencesUniversity of Coimbra3000-456 CoimbraPortugal

Introduction:Here,we compare the arbuscular mycorrhizal fungal(AMF)community composition in soils from the root zone of the exotic invasive species Prosopis juliflora(EXO soils)and soils from the root zone of the native species Mimosa tenuiflora(NAT soils)from five locations in the Brazilian tropical seasonal dry forest,Paraíba,Brazil,using morphological ***:AMF community composition in EXO and NAT soils were *** phosphorus,diversity index,spore abundance,and species richness were the main factors differing between the EXO and NAT *** general,the most dominant order present in the soils were Glomerales(44.8%)and Gigasporales(41.4%).The most abundant AMF genus in all studied soils was ***:Differences in AMF community composition were associated with(1)differences in the dominant plant species(*** ***)and(2)changes in soil chemical factors(soil,pH,total organic carbon,total nitrogen,and available P)in EXO *** results contribute to a deeper view of the AMF communities in exotic soils and open new perspectives for ecological processes involving AMF species and exotic plant species in the Brazilian tropical seasonal dry forest.

关键词： Glomeromycota AMF community AMF diversity Native plant species Exotic plant species Caatinga