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Same or different?Abstract relational concept use in juvenile bamboo sharks and Malawi cichlids

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Current Zoology 2021年第3期67卷 279-292页

作者： Theodora Fuss Leonie John vera Schluessel institute of Zoology Rheinische Friedrich-Wilhelms-University BonnMeckenheimer Allee 169Bonn53115Germany

Sorting objects and events into categories and concepts is an important cognitive prerequisite that spares an individual the learning of every object or situation encountered in its daily ***,specific items are classified in general groups that allow fast responses to novel *** present study assessed whether bamboo sharks Chiloscyllium griseum and Malawi cichlids Pseudotropheus zebra can distinguish sets of stimuli(each stimulus consisting of two abstract,geometric objects)that meet two conceptual preconditions,i.e.,(1)"sameness"versus"difference"and(2)a certain spatial arrangement of both *** two alternative forced choice experiments,individuals were first trained to choose two different,vertically arranged objects from two different but horizontally arranged *** discriminations were followed by extensive transfer test *** tests using stimuli consisting of(a)black and gray circles and(b)squares with novel geometric patterns provided conflicting information with respect to the learnt rule"choose two different,vertically arranged objects",thereby investigating(1)the individuals'ability to transfer previously gained knowledge to novel stimuli and(2)the abstract relational concept(s)or rule(s)applied to categorize these novel *** results suggest that the level of processing and usage of both abstract concepts differed considerably between bamboo sharks and Malawi *** sharks seemed to combine both concepts-although not with equal but hierarchical prominence-pointing to advanced cognitive ***,Malawi cichlids had difficulties in discriminating between symbols and failed to apply the acquired training knowledge on new sets of geometric and,in particular,gray-level transfer stimuli.

关键词： visual concept learning spatial arrangement relational abstract concept Malawi cichlid bamboo shark

iAS/iFRS and financial reporting quality:Lessons from the European experience

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China Journal of Accounting Research 2013年第4期6卷 247-263页

作者： vera Palea department of Economics and Statistics "Cognetti de Martiis" University of Torino

This paper discusses the effects of the adoption of iAS/iFRS in Europe on the quality of financial *** doing so,it adopts the perspective of stock market investors and focuses on value-relevance *** adoption of iAS/iFRS in Europe is an example of accounting standardization among countries with different institutional frameworks and enforcement *** allows investigating whether,and to what extent,accounting regulation per se can affect the quality of financial reporting and leads to convergence in financial *** is a key issue for standard setting purposes as iAS/iFRS have been adopted in very diverse countries all over the world,and many others are likely to adopt them in the near future.

关键词： Financial reporting quality iAS/iFRS Value-relevance European Regulation 1606/2002

Pre-emergence herbicides affect seedling emergence of tropical forest tree species

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Journal of Forestry Research 2017年第4期28卷 733-739页

作者： diego Cerveira de Souza vera Lex Engel Forest Science department Agronomic Sciences College-FCASao Paulo State University – UNESPP.O. Box 237BotucatuSP 18603-970Brazil

Testing techniques to reduce weed infestation is a crucial step in developing direct tree seeding systems. The use of pre-emergence herbicides may be an alternative to manual weeding techniques, but so far, information on how they affect the seeds of native tree species is scarce. We established a greenhouse experiment to evaluate the effects of four pre-emergence herbicides (atrazine, diuron, isoxaflutole and oxyfluorfen) on weed suppression and seedling emergence and early growth of seven tropical forest tree species (Annona coriacea Mart., Citharexylum myrianthum Cham., Cordia ecalyculata Vell., Peltophorum dubium (Spreng.) Taub., Psidium guajava L., Pterogyne nitens Tul. and Schinus terebinthifolia Raddi). The experimental design was a randomized complete block design with five treatments and five replicates. The treatments consisted of a single dose of each pre-emergence herbicide and a control. Throughout the 60 days after sowing we evaluated weed cover and seedling emergence and early growth of tree species. Overall, our results suggest that all tested herbicides reduced weed cover; however, they also negatively affected tree species seedling emergence. Of the four herbicides tested, atrazine and diuron showed the greatest effects on tree seedling emergence, oxyfluorfen was least aggressive towards native species and isoxaflutole was most effective in weed control. Native tree species varied in their responses to herbicides, indicating that future experiments should increase the number of species tested as well as investigate how seed traits can affect the species responses to different herbicides.

关键词： Pre-emergence herbicides Weed control direct seeding Seedling emergence Tropical seasonal forests

improvement of ViS and iR camouflage properties by impregnating cotton fabric with PVB/iF-WS_(2)

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defence Technology（防务技术） 2021年第6期17卷 2050-2056页

作者： Aleksandra d.Samolov danica M.Simic Bojana Z.Fidanovski vera M.Obradovic Ljubisa d.Tomic dragan M.Knezevic Military Technical institute Ratka Resanovica 111000BelgradeSerbia innovation Center of Faculty of Technology and Metallurgy LTd.in Belgrade 4 Karnegijeva Street11120BelgradeSerbia

in order to examine the possibility to improve its camouflage properties standard cotton fabric with camouflage print was impregnated with poly(vinyl butyral),PVB and fullerene-like nanoparticles of tungsten disulfide,PVB/iF-WS_(2).FTiR analysis excluded any possible chemical interaction of iF-WS_(2) with PVB and the *** camouflage behavior of the impregnated fabric has been examined firstly in the ViS part of the *** reflection,specular gloss and color coordinates were measured for three different shades(black,brown and dark green).Thermal imaging was applied to examine the camouflage abilities of this impregnation in iR part of the *** obtained results show that PVB/iF-WS_(2) impregnation system induced enhacement of the materials camouflage properties,*** iF-WS_(2) have a positive effect on spectrophotometric characteristics of the fabric.

关键词： Textile materials Camouflage properties Tungsten disulfide poly(vinyl butyral) Thermal imaging

Linking plant metabolism and immunity through methionine biosynthesis

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Molecular Plant 2022年第1期15卷 6-8页

作者： Francisco Escaray Amelia Felipo-Benavent Pablo vera instituto de Biología Molecular y Celular de Plantas Universidad Politécnica de Valencia-C.S.I.CCiudad Politécnica de la InnovaciónEdificio 8EIngeniero Fausto Elios/n46022 ValenciaSpain

Plants respond to pathogenic cues with a transcriptional reprog-ramming that leads to de novo production of defense-related pro-teins and a huge variety of secondary metabolites(e.g.,phyto-alexins,phenolics,etc.).Activation of these host defenses,which contribute to halt the intruder as part of the resistance,im-plies an increased demand for metabolic energy and carbon skel-etons derived from primary metabolism(Bolton,2009).

关键词： metabolism immunity Bolton

Effect of poly(3-hydroxyalkanoates) as natural polymers on mesenchymal stem cells

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World Journal of Stem Cells 2019年第10期11卷 764-786页

作者： vera Voinova Garina Bonartseva Anton Bonartsev Faculty of Biology M.V.Lomonosov Moscow State UniversityMoscow 119234Russia A.N.Bach institute of Biochemistry Research Center of Biotechnology of the Russian Academy of SciencesMoscow 119071Russia

Mesenchymal stem cells(MSCs)are stromal multipotent stem cells that can differentiate into multiple cell types,including fibroblasts,osteoblasts,chondrocytes,adipocytes,and myoblasts,thus allowing them to contribute to the regeneration of various tissues,especially bone *** are now considered one of the most promising cell types in the field of tissue *** petri dish-based culture of MSCs generate heterogeneity,which leads to inconsistent efficacy of MSC *** and biocompatible polymers,poly(3-hydroxyalkanoates)(PHAs),are actively used for the manufacture of scaffolds that serve as carriers for MSC *** growth and differentiation of MSCs grown on PHA scaffolds depend on the physicochemical properties of the polymers,the 3d and surface microstructure of the scaffolds,and the biological activity of PHAs,which was discovered in a series of *** mechanisms of the biological activity of PHAs in relation to MSCs remain insufficiently *** suggest that this effect on MSCs could be associated with the natural properties of bacteria-derived PHAs,especially the most widespread representative poly(3-hydroxybutyrate)(PHB).This biopolymer is present in the bacteria of mammalian microbiota,whereas endogenous poly(3-hydroxybutyrate)is found in mammalian *** possible association of PHA effects on MSCs with various biological functions of poly(3-hydroxybutyrate)in bacteria and eukaryotes,including in humans,is discussed in this paper.

关键词： Mesenchymal stem cells Polyhydroxyalkanoates Poly(3-hydroxybutyrate) Tissue engineering differentiation Natural functions Microbiota Bone intestine

Trends in lactose-derived bioactives:synthesis and purification

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Systems Microbiology and Biomanufacturing 2022年第3期2卷 393-412页

作者： Carlos vera Cecilia Guerrero Andrés illanes department of Biology Faculty of Chemistry and BiologyUniversidad de Santiago de Chile(USACH)SantiagoChile School of Biochemical Engineering Pontificia Universidad Católica de Valparaíso(PUCV)ValparaisoChile

Lactose obtained from cheese whey is a low value commodity despite its great potential as raw material for the production of bioactive *** them,prebiotics stand out as valuable ingredients to be added to food matrices to build up functional foods,which currently represent the most active sector within the food *** foods market has been growing steadily in the recent decades along with the increasing awareness of the World population about healthy nutrition,and this is having a strong impact on lactose-derived *** of them are produced by enzyme biocatalysis because of molecular precision and environmental sustainability *** current status and outlook of the production of lactose-derived bioactive compounds is presented with special emphasis on downstream operations which are critical because of the rather modest lactose conversion and product yields that are *** though some of these products have already an established market,there are still several challenges referring to the need of developing better catalysts and more cost-effective downstream operations for delivering high quality products at affordable *** technological push is expected to broaden the spectrum of lactose-derived bioactive compounds to be produced at industrial scale in the near future.

关键词： Prebiotic Lactose β-Galactosidase Oligosaccharide purification

Effects of coals microscale structural features on their mechanical properties,propensity to crushing and fine dust formation

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international Journal of Coal Science & Technology 2023年第2期10卷 146-158页

作者： Elena Kossovich Svetlana Epshtein vera Krasilova Jie Hao Maxim Minin National University of Science and Technology"MiSiS" 4build.1Leninsky prospectMoscow 119049Russian Federation

The work is dedicated to revealing the structural features of coals with different ranks,such as anthracites,metaanthracite and graphite,that determine their ability to crush and form fine *** this purpose,a combination of various nanoin-dentation techniques and Raman spectroscopy was *** mechanical behavior of the selected coals was investigated by cyclic nanoindentation with increasing peak load and quasi-static *** alteration of the mechanical properties was studied by analysis of elastic moduli and damage indices *** groups of coals were identified based on their propensity to crushing during cyclic *** assigned to the first and second groups are characterized by local destruction in the contact zone with the indenter and the formation of a core of crushed *** assigned to the third group are characterized by bulk destruction(outside the zone of contact with the indenter).in general,the ability of coals to fracture under mechanical loading decreases in the series of metamorphism due to microscale compaction of vitrinite *** the series of anthracite,metaanthracite and graphite,it is established that the coal matter compaction takes place for the anthracite and metaanthracite,whereas graphite reveals rather different behavior due to abrupt change of its *** ratios between the amorphous and crystalline phases of carbon(S)were determined by deconvolution of coals Raman *** propensity of coals to crushing(a damage index Rw)increases with growth of the proportion of amorphous carbon in the coal *** the considered coals and metaanthracite,it is established that the proneness to destruction outside the contact zone with the indenter is determined by the ratio of amorphous and crystalline carbon of 1 and *** S parameter is lower than 1,the coals are being crushed only in the zone of contact with the indenter.

关键词： Coal Crushing Cyclic nanoindentation Raman spectroscopy Amorphous carbon Crystalline carbon

Bresse Beam with damping and Logarithmic Source

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Chinese Annals of Mathematics,Series B 2024年第5期45卷 685-702页

作者： Sebastiao CORdEiRO Carlos BALdEZ Carlos RAPOSO ducival PEREiRA Octavio vera department of Mathematics Federal University of ParaAbaetetubaParaBrazil department of Mathematics Federal University of ParaBragancaParaBrazil department of Mathematics Federal University of ParaSalinopolisParaBrazil department of Mathematics State University of ParaBelemParaBrazil department of Mathematics University of TarapacaAricaChile

This paper investigates the stabilization of a Bresse system with internal damping and logarithmic *** authors use the potential well *** initial data in the stability set created by the Nehari surface,the existence of a global solution is proved by using Faedo-Galerkin's *** Nakao theorem gives the exponential decay.A numerical approach is presented to illustrate the results obtained.

关键词： Bresse beam Logarithmic source Global solution Exponential decay Numerical approach