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World Journal of Gastroenterology 2007年第21期13卷 2918-2922页

作者： maria Elzbieta Sobaniec-Lotowska Joanna maria Lotowska Dariusz Marek Lebensztejn Department of Clinical Pathomorphology Medical University of BialystokPoland IIIrd Department of Pediatrics Medical University of BialystokPoland

AIM:To investigate the ultrastructure of oval cells in children with chronic hepatitis B,with special emphasis on their location in areas of collagen fibroplasia. METHODS:Morphological investigations were conducted on biopsy material obtained from 40 children,aged 3-16 years with chronic hepatitis B. The stage of fibrosis was assessed histologically using the arbitrary semiquantitative numerical scoring system proposed by Ishak et al. The material for ultrastructural investigation was fixed in glutaraldehyde and paraformaldehyde and processed for transmission-electron microscopic analysis. RESULTS:Ultrastructural examination of biopsy specimens obtained from children with chronic hepatitis B showed the presence of two types of oval cells,the hepatic progenitor cells and intermediate hepatic-like cells. These cells were present in the parenchyma and were seen most commonly in areas of intense periportal fibrosis (at least stage 2 according to Ishak et al) and in the vicinity of the limiting plate of the lobule. The activated nonparenchymal hepatic cells,i.e. transformed hepatic stellate cells and Kupffer cells were seen in close proximity to the intermediate hepatic-like cells. CONCLUSION:We found a distinct relationship between the prevalence of oval cells (hepatic progenitor cells and intermediate hepatocyte-like cells) and fibrosis stage in pediatric patients with chronic hepatitis B.

关键词： Pediatric patients, Oval cells Ultrastructural study Chronic hepatitis B Liver biopsy Fibrosis

Analysis of hydrodynamic effects on biofilm thickness in fluidized-bed tapered bioreactors

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Particuology 2021年第5期19卷 48-57页

作者： Daniela maria Koerich Leonardo Machado da Rosa Chemical Engineering Department University of Blumenau(FURB)3250 Sao Paulo Street89030-000 BlumenauSanta CatarinaBrazil

Fluidized beds in tapered geometries provide advantages such as a broad range of optimum operating ***,the dynamics of the flow inside these bioreactors is significantly more complex,as they promote non-uniform bioparticles *** this end,the CFD technique can give a detailed description of the flow in the ***,the aim of this work is to assess the influence of the hydrodynamic on the steady-state biofilm thickness through numerical simulations of liquid–solid fluidized *** geometries of tapered bioreactors in the operating conditions used to develop *** were run to solve the two-phase RANS equations using the open-source software OpenFOAM in *** SST k−ω model was used to estimate the turbulent features of the *** and bioparticles distribution inside the reactor were analyzed for different inlet velocities,while bioparticles collision frequency and shear stresses were evaluated for various operating *** comparison between the turbulent kinetic energy and the granular temperature indicated that the fluid flow is more turbulent than the bioparticles *** hydrodynamics influence on the steady-state biofilm thickness was assessed,and results led to the conclusion that biofilm is more sensitive to hydrodynamic shear stress than bioparticles collisions.

关键词： Liquid-solid fluidization Shear stress Particles collisions Computational fluid dynamics Biofilm Tapered bioreactors

Predetermination of potential plastic hinges on reinforced concrete frames using GFRP reinforcement

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Frontiers of Structural and Civil Engineering 2022年第5期16卷 624-637页

作者： Dominik KUERES Dritan TOPUZI maria Anna POLAK Department of Civil and Environmental Engineering University of WaterlooWaterlooON N2L 3G1Canada Schoeck Canada Inc. OttawaON K1P 5G3Canada

In the past,glass fiber-reinforced polymer(GFRP)-reinforcement has been successfully applied in reinforced concrete(RC)structures where corrosion resistance,electromagnetic neutrality,or cuttability were *** investigations suggest that the application of GFRP in RC structures could be advantageous in areas with seismic activity due to their high deformability and ***,especially the low modulus of elasticity of GFRP limited its wide application as GFRP-reinforced members usually exhibit considerably larger deformations under service loads than comparable steel-reinforced *** overcome the aforementioned issues,the combination of steel and GFRP reinforcement in hybrid RC sections has been investigated in the *** on this idea,this paper presents a novel concept for the predetermination of potential plastic hinges in RC frames using GFRP *** analyze the efficiency of the concept,nonlinear finite element simulations were *** results underscore the high efficiency of hybrid steel-GFRP RC sections for predetermining potential plastic hinges on RC *** results also indicate that the overall seismic behavior of RC structures could be improved by means of GFRP as both the column base shear force during the seismic activity as well as the plastic deformations after the earthquake were considerably less pronounced than in the steel-reinforced reference structure.

关键词： glass fiber-reinforced polymer GFRP hybrid section plastic hinge seismic design reinforced concrete

Carbon sequestration in a bamboo plantation:a case study in a Mediterranean area

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Journal of Forestry Research 2024年第3期35卷 231-238页

作者： Tommaso Chiti Emanuele Blasi maria Vincenza Chiriaco Department for Innovation in Biological Agro-Food and Forest Systems(DIBAF)University of TusciaVia San C.De Lellis snc01100 ViterboItaly Foundation Euro-Mediterranean Center on Climate Change(CMCC) Division on Climate Change Impacts on AgricultureForests and Ecosystem Services(IAFES)Via Garbini5101100 ViterboItaly

In the Mediterranean region,despite bamboo being an alien species that can seriously alter plant and ani-mal biocoenosis,the area occupied by bamboo plantations continues to increase,especially for the purpose to seques-ter carbon(C).However,the C dynamics in the soil-plant system when bamboo is grown outside its native area are poorly *** we investigated the C mitigation potential of the fast-growing Moso bamboo(Phyllostachys edulis)introduced in Italy for climate-change *** analyzed aboveground(AGB)and belowground(as root/shoot ratio)biomass,litter and soil organic C(SOC)at O-15-and 15-30-cm depths in a 4-year-old bamboo plantation in comparison with the former annual cropland on which the bamboo was *** have an idea of the maximum C stored at an ecosystem level,a natural forest adjacent the two sites was also *** the plantation,C accumulation as AGB was stimulated,with 14.8±3.1 Mg C ha^(-1) stored in 3 years;because thinning was done to remove culms from the first year,the mean sequestration rate was 4.9 Mg C ha^(-1) a^(-1).The sequestration rates were high but comparable to other fast-growing tree species in Italy(e.g.,Pinus nigra).SOC was significantly higher in the bamboo plantation than in the cropland only at the 0-15 cm depth,but SOC stock did not *** 4 years were not enough time for a clear increase in SOC,or the high nutrient uptake by bamboos might have depleted the soil nutrients,thus inhibiting the soil organic matter formation by *** comparison,the natural forest had significantly higher C levels in all the *** C dynamics at an ecosystem level,the bamboo plantation on the former annual cropland led to substantial C removal from the atmosphere(about 12 Mg C ha^(-1) a^(-1)).However,despite the promising C sequestration rates by bamboo,its introduction should be carefully considered due to potential ecological problems caused by this species in overexploited environments such as the Med

关键词： Carbon sequestration Climate change mitigation Mediterranean area Moso bamboo Soil organic carbon

Forward:Proceedings of the 2008 Ecological and Evolutionary Ethology of Fishes Conference,Boston,Massachusetts,USA

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Current Zoology 2010年第1期56卷 3-4页

作者： maria E.ABATE Department of Biology Boston University

This special issue of Current Zoology concerning thebehavior, ecology, and evolution of fishes is comprisedof the peer-reviewed Proceedings of the 2008 Ecologicaland Evolutionary Ecology of Fishes Biennial Conferencethat was held June 29-July 3 at Boston University,Boston, Massachusetts, USA. The conferenceand its four symposia were organized by a local organi-

关键词： Forward

Perception of the Muller-Lyer illusion in guppies

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Current Zoology 2020年第2期66卷 205-213页

作者： maria SANTACA Christian AGRILLO Department of General Psychology University of PadovaVia Venezia 8Padova 35131Italy

The Muller-Lyer illusion is a well-known distortion illusion that occurs when the spatial arrangement of inducers(i.e.,inwards-or outwards-pointing arrowheads)influences a line's perceived relative *** date,this illusion has been reported in several animal species but only in 1 teleost fish(i.e.,redtail splitfins Xenotoca eiseni),although teleost fish represent approximately 50%of vertebrate *** investigated the perception of this illusion in another teleost fish:guppies Poecilia reticulata,a species that diverged from the redtail splitfin 65 million years *** guppies were trained to select the longer between 2 lines;after meeting the learning criterion,illusory trials were *** trials were also arranged to exclude the possibility that their choices were based on potential spatial biases that relate to the illusory *** guppies'overall performance indicated that they were susceptible to the Muller-Lyer illusion,perceiving the line with the inwards-pointing arrowheads as *** performance in the control trials excluded the possibility that the subjects used the physical differences between the 2 figures as the discriminative cue in the illusory *** study suggests that sensibility to the Muller-Lyer illusion could be widespread across teleost fish and reinforces the idea that the perceptual mechanisms underlying size estimation might be similar across vertebrates.

关键词： comparative perception Muller-Lyer illusion Poecilia reticulata visual illusions

Quasispecies structure,cornerstone of hepatitis B virus infection: Mass sequencing approach

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World Journal of Gastroenterology 2013年第41期19卷 6995-7023页

作者： Francisco Rodriguez-Frias maria Buti David Tabernero maria Homs Network Medical Research Center Hepatic and Digestive Diseases (CIBERehd)Institute of Health Carlos Ⅲ08036 BarcelonaSpain Department of Biochemistry Vall d’Hebron HospitalAutonomous University of Barcelona08035 BarcelonaSpain Department of Hepatology Vall d’Hebron HospitalAutonomous University of Barcelona08035 BarcelonaSpain

Hepatitis B virus(HBV)is a DNA virus with complex replication,and high replication and mutation rates,leading to a heterogeneous viral *** population is comprised of genomes that are closely related,but not identical;hence,HBV is considered a viral *** variability may be somewhat limited by the high degree of overlapping between the HBV coding regions,which is especially important in the P and S gene overlapping regions,but is less significant in the X and preCore/Core *** this restriction,several clinically and pathologically relevant variants have been characterized along the viral ***-generation sequencing(NGS)approaches enable high-throughput analysis of thousands of clonally amplified regions and are powerful tools for characterizing genetic diversity in viral *** the present review,we update the information regarding HBV variability and present a summary of the various NGS approaches available for research in this *** addition,we provide an analysis of the clinical implications of HBV variants and their study by NGS.

关键词： Hepatitis B virus Next generation sequencing Quasispecies Linkage analysis Gene overlapping

Identification and Cloning of Differentially Expressed Genes Involved in the Interaction Between Potato and Phytophthora infestans using a Subtractive Hybridization and cDNA-AFLP Combinational Approach

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Journal of Integrative Plant Biology 2010年第5期52卷 453-467页

作者： maria Antonia Henriquez Fouad Daayf Department of Plant Science University of Manitoba222 Agriculture BuildingWinnipeg R3T2N2Canada

Using a subtractive hybridization （SH）/cDNA-AFLP combinational approach, differentially expressed genes involved in the potato-Phytophthora infestans interaction were identified. These included genes potentially controlling pathogenesis or avr genes in P. infestans as well as those potentially involved in potato resistance or susceptibility to this pathogen. Forty-one differentially expressed transcript, derived fragments （TDFs）, resulting from the interaction, were cloned and sequenced. Two TDFs, suggested as potential pathogenicity factors, have sequence similarity to N-succinyl diaminopimelate aminotransferase and a transcriptional regulator, TetR family gene, respectively. Two other TDFs, suggested as potential avr genes, have sequence similarity to an EST sequence from Avr41Cf.41Avr91Cf- 9 and a P. infestans avirulence-associated gene, respectively. Genes＇ expression and origin were confirmed using Southern blots, Northern blots and qRT-PCR, he., potential resistance gene DL81 was induced at 12 hpi in the moderately resistant cultivar, whereas it was down-regulated as early as 6 hpi in the susceptible cultivar. On the other hand, DL21 was induced at 6 hpi （3.38-fold） in response to the highly aggressive isolate （US8） and strongly up-regulated thereafter （25.13-fold at 120 hpi.）, whereas it was only slightly up-regulated in response to the weakly aggressive isolate US11 （3.82-fold at 96 hpi）, suggesting its potential involvement as a susceptibility gene.

关键词： cDNA SH AFLP Identification and Cloning of Differentially Expressed Genes Involved in the Interaction Between Potato and Phytophthora infestans using a Subtractive Hybridization and cDNA-AFLP Combinational Approach

Experimental evidence for heritable reproductive time in 2 allochronic populations of pine processionary moth

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Insect Science 2017年第2期24卷 325-335页

作者： Manuela Branco maria-Rosa Paiva Helena maria Santos Christian Burban Carole Kerdelhue Centro de Estudos Florestais (CEF) Instituto Superior de Agronomia (ISA) Universidade de Lisboa (ULisboa) 1349-017 Lisboa Portugal CENSE Faculty of Sciences and Technology (FCT) Universidade Nova de Lisboa (UNL) 2829-516 Caparica Portugal INRA Centre de Bordeaux UMR1202 BIOGECO Cestas cedex France INRA Centre de Montpellier UMR CBGP F-34988 Montferrier-sur-Lez cedex France

Phenology allows organisms to overcome seasonally variable conditions through life-cycle adjustment. Changes in phenology can drastically modify the evolutionary tra- jectory of a population, while a shift in the reproductive time may cause allochronic differentiation. The hypothesis of heritable reproductive time was experimentally tested, by studying a unique population of the pine processionary moth Thaumetopoeapityocampa （Den. ＆ Schiff.） which has a shifted phenology, and however co-occurs with the typical population following the classical life cycle. When populations of both types were reared under controlled conditions, the reproductive time was maintained asynchronous, as ob- served in the field. The shifted population was manipulated in the laboratory to reproduce later than usual, yet the offspring emerged in the next year at the expected dates thus ＂com- ing back＂ to the usual cycle. Hybrids from crosses performed between the 2 populations showed an intermediate phenology. From the emergence times of parents and offspring, a high heritability of the reproductive time （h = 0.76） was observed. The offspring ob- tained from each type of cross was genetically characterized using microsatellite markers. Bayesian clustering analysis confirmed that hybrids can he successfully identified and separated from the parental genetic classes by genotyping. Findings support the hypothesis that, for this particular population, incipient allochronic speciation is due to a heritable shift in the reproductive time that further causes assortative mating and might eventually cause ecological adaptation/maladaptation in response to environmental changes.

关键词： allochronic speciation experimental crossings heritability phenology reproductive isolation Thaumetopoeapityocampa

How many subductions in the Variscan orogeny?Insights from numerical models

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Geoscience Frontiers 2020年第3期11卷 1025-1052页

作者： Alessandro Regorda Jean-Marc Lardeaux Manuel Roda Anna maria Marotta maria Iole Spalla Universita Degli Studi di Milano Dipartimento di Scienze Della Terra'A.Desio’Via Mangiagalli 34I-20133MilanoItaly Universite Nice Sophia-Antipolis UMR Geoazur250 Rue A.EinsteinSophia-Antipolis06560ValbonneFrance

We developed a 2 D numerical model to simulate the evolution of two superposed ocean-continent-ocean subduction cycles with opposite vergence,both followed by continental collision,aiming to better understand the evolution of the Variscan *** models with different velocities of the first oceanic subduction have been *** differences in the thermo-mechanical evolution between the first subduction,which activates in an unperturbed system,and the second subduction,characterised by an opposite vergence,have been enlighten,in particular regarding the temperature in the mantle wedge and in the interior of the *** and temperature(P-T) conditions predicted by one cycle and two cycles models have been compared with natural P-T estimates of the Variscan metamorphism from the Alps and from the French Massif Central(FMC).The comparative analysis supports that a slow and hot subduction well reproduces the P-T conditions compatible with data from the FMC,while P-T conditions compatible with data of Variscan metamorphism from the Alps can be reproduced by either a cold or hot oceanic subduction *** the agreement of both double and single subduction models with natural P-T estimates,we observed that polycyclic models better describe the evolution of the Variscan orogeny.

关键词： Alps Double subduction French Massif Central Numerical modelling Variscan orogeny