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Skeletal microstructures of cheilostome bryozoans(phylum Bryozoa,class Gymnolaemata):crystallography and secretion patterns

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Marine Life Science & Technology 2024年第3期6卷 405-424页

作者： Christian Grenier Erika Griesshaber Wolfgang Schmahl Björn Berning Antonio G.Checa departamento de Estratigrafía y Paleontología Universidad de Granada18071 GranadaSpain Instituto Andaluz de Ciencias de La Tierra CSIC-Universidad de Granada18100 ArmillaSpain department of Earth and Environmental Sciences Ludwig-Maximilians Universität80333 MunichGermany Institute for Geology University of Hamburg20146 HamburgGermany

Gymnolaemata bryozoans produce CaCO3 skeletons of either calcite,aragonite,or *** extensive research,their crystallography and biomineralization patterns remain *** present a detailed study of the microstructures,min-eralogy,and crystallography of eight extant cheilostome species using scanning electron microscopy,electron backscatter diffraction,atomic force microscopy,and micro-computed *** distinguished five basic microstructures,three calcitic(tabular,irregularly platy,and granular),and two aragonitic(granular-platy and fibrous).The calcitic microstruc-tures consist of crystal aggregates that transition from tabular or irregularly platy to granular *** aragonite consists of fibers arranged into *** all cases,the crystallographic textures are axial,and stronger in aragonite than in calcite,with the c-axis as the fiber *** reconstruct the biomineralization sequence in the different species by considering the distribution and morphology of the growth fronts of crystals and the location of the secretory *** bimineralic species,calcite formation always predates aragonite *** interior compound walls,growth proceeds from the cuticle toward the zooecium *** conclude that,with the exception of tabular calcite,biomineralization is remote and occurs within a relatively wide extrapallial space,which is consistent with the inorganic-like appearance of the *** biomineralization mode is rare among invertebrates.

关键词： Biomineralization Bryozoan Skeleton Calcite Aragonite Electron backscatter diffraction

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Alkali and Plasma-Treated Guadua angustifolia Bamboo Fibers:A Study on Reinforcement Potential for Polymeric Matrices

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Journal of Renewable Materials 2024年第8期12卷 1399-1416页

作者： Patricia Luna Juan Lizarazo-Marriaga Alvaro Mariño Facultad de Ingeniería Universidad Nacional de ColombiaBogotá11001Colombia Facultad de Ciencias Universidad Nacional de ColombiaBogotá11001Colombia

This study focuses on treating Guadua angustifolia bamboo fibers to enhance their properties for reinforcement applications in composite ***(alkali)and physical(dry etching plasma)treatments were used separately to augment compatibility of Guadua angustifolia fibers with various composite *** influence of these treatments on the fibers’performance,chemical composition,and surface morphology were *** analysis indicated that alkali treatments reduced the tensile modulus of elasticity and strength of fibers by up to 40%and 20%,respectively,whereas plasma treatments maintain the fibers’mechanical *** spectroscopy revealed significant alterations in chemical composition due to alkali treatments,while plasma-treated fibers showed minimal *** examination through Scanning Electron Microscopy(SEM)revealed post-treatment modifications in both cases;alkali treatments served as a cleanser,eliminating lignin and hemicellulose from the fiber surface,whereas plasma treatments also produce rough *** results validate the impact of the treatments on the fiber mechanical performance,which opens up possibilities for using Guadua angustifolia fibers as an alternative reinforcement in composite manufacturing.

关键词： Bamboo fibers Guadua angustifolia alkali treatment dry etching plasma treatment composite reinforcement

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Choice of the Best Production Prediction Model for the Zagtouli Solar Power Plant in Burkina-Faso

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Engineering（科研） 2024年第9期16卷 237-245页

作者： Toussaint Tilado Guingane Eric Korsaga Mouhamadou Falilou Ndiaye Gaston Nabayaogo Dominique Bonkoungou Zacharie Koalaga Physics ufr/SEA Materials and Environment Laboratory (LAME) Pr. Joseph Ki ZERBO University Ouagadougou Burkina Faso Physics ufr/ST Science and Technology Laboratory (LaST) Thomas SANKARA University Ouagadougou Burkina Faso Centre International de Formation et de Recherche en Energie Solaire (C.I.F.R.E.S) ESP-UCAD: BP 5085 Dakar-Fann Senegal

In this paper, we present a study on the prediction of the power produced by the 33 MWp photovoltaic power plant at Zagtouli in Burkina-Faso, as a function of climatic factors. We identified models in the literature, namely the Benchmark, input/output, Marion, Cristo-fri, Kroposki, Jones-Underwood and Hatziargyriou prediction models, which depend exclusively on environmental parameters. We then compared our linear model with these seven mathematical models in order to determine the most optimal prediction model. Our results show that the Hatziargyriou model is better in terms of accuracy for power prediction.

关键词： Model Prediction Power Power Plant Photovoltaic Zagtouli Burkina-Faso

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Experimental implementation of phase triplicator gratings in a spatial light modulator

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Chinese Optics Letters 2024年第2期22卷 64-69页

作者：高尚 María del Mar Sánchez-López Ignacio Moreno Instituto de Bioingeniería Universidad Miguel HernándezElche 03202Spain departamento de Física Aplicada Universidad Miguel HernándezElche 03202Spain departamento de Ciencia de Materiales Óptica y Tec.Electr´onicaUniversidad Miguel HernándezElche 03202Spain

In this work,we compare different methods for implementing a triplicator,a phase grating that generates three equiintense diffraction *** design with optimal efficiency features a continuous phase profile,which cannot be easily reproduced,and is typically affected by *** compare its performance with binary and sinusoidal phase *** also analyze the effect of quantizing the phase ***,a random approach is adopted to eliminate the additional harmonic *** all cases,a liquid-crystal-on-silicon spatial light modulator is employed to experimentally verify and compare the different approaches.

关键词： diffraction gratings phase modulation triplicator spatial light modulators

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Characterization of Arroyo Verde Epithermal deposit:Paragenesis,Mineral Geochemistry,Geochronology and Fluid Inclusions in Lower Chon Aike Volcanism,Argentina

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Journal of Earth Science 2024年第1期35卷 62-84页

作者： Cecilia Pavón Pivetta Leonardo Benedini Paulo Marcos Ma.Agustina Cócola Mercedes Virginia Barros Daniel Gregori Leonardo Strazzere Anderson Costa dos Santos Mauro C.Geraldes Instituto Geologico del Sur(INGEOSUR) Universidad Nacional del Sur(UNS)-Consejo Nacional de Investigaciones Cientificas y Tecnicas(CONICET)Bahia Blanca 8000Argentina Dpto.de Geologia Universidad Nacional del Sur(UNS)Bahia Blanca 8000Argentina Universidad Nacional de Rio Negro Instituto de Investigacion en Paleobiologia y GeologiaGeneral Roca 8332Argentina Universidade do Estado do Rio de Janeiro Faculdade de GeologiaDepartamento de Mineralogia e Petrologia igneaRiodeJaneiro20559-900Brazil Geobiotec Departamento de GeocienciasUniversidade de AveiroAveiro 3800-002Portuga

Arroyo Verde epithermal deposit,in the North Patagonia region of Argentina,is located within the Lower Chon Aike volcanism and is developed between 192.6±2.5 Ma(mineralization host rock)and 189.5±2.6 Ma(overlying lava).Marifil volcanic complex is the host rock for these veins,veinlets and *** particular small deposit has developed low to intermediate sulphidation characteristics,with gangue mineral textures associated with several ore *** probe microanalysis determines electrum,silver minerals such as acanthite,and tetrahedrite,related Ag-Cu minerals like jalpaite,mckinstryite,stromeyerite,and base metals like chalcopyrite,sphalerite,galena and *** inclusions in quartz of two out of five events indicate that these Low Jurassic veins were formed due to subtle boiling and dilution mechanisms and by low-salinity(3.4 wt.%to 6.7 wt.%NaCl Eq)magmatic-hydrothermal fluid at 225 to 310℃.The fluid inclusion measurements that indicate boiling(Event 3)were plotted,and based on this data,we interpret that the Arroyo Verde deposit has been eroded between 550 and 700 *** particular character has not been previously recorded for other sectors of the eastern north Patagonian region.

关键词： epithermal deposit Ag minerals mineral geochemistry fluid inclusions Chon Aike geochronology

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A LOW-COST OPTIMIZATION APPROACH FOR SOLVING MINIMUM NORM LINEAR SYSTEMS AND LINEAR LEAST-SQUARES PROBLEMS

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Journal of Computational mathematics 2024年第4期42卷 932-954页

作者： debora Cores Johanna Figueroa defense University Center at the Spanish Naval Academy Plaza de Espana36920 MarinPontevedraSpain departamento de Matematica Facultad de MatematicaPontificia Universidad Catolica de ChileAv.Vicuna Mackenna 4860San JoaquinSantiago 894000Chile

Recently,the authors proposed a low-cost approach,named Optimization Approach for Linear Systems(OPALS)for solving any kind of a consistent linear system regarding the structure,characteristics,and dimension of the coefficient matrix *** results obtained by this approach for matrices with no structure and with indefinite symmetric part were encouraging when compare with other recent and well-known *** this work,we proposed to extend the OPALS approach for solving the Linear Least-Squares Problem(LLSP)and the Minimum Norm Linear System Problem(MNLSP)using any iterative low-cost gradient-type method,avoiding the construction of the matrices AT A or AAT,and taking full advantage of the structure and form of the gradient of the proposed nonlinear objective function in the gradient *** combination of those conditions together with the choice of the initial iterate allow us to produce a novel and efficient low-cost numerical scheme for solving both ***,the scheme presented in this work can also be used and extended for the weighted minimum norm linear systems and minimum norm linear least-squares *** include encouraging numerical results to illustrate the practical behavior of the proposed schemes.

关键词： Nonlinear convex optimization Gradient-type methods Spectral gradient method Minimum norm solution linear systems Linear least-squares solution

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INVARIANCE AND STABILITY OF THE PROFILE EQUATIONS OF GEOMETRIC OPTICS

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Acta mathematica Scientia 2011年第6期31卷 2141-2158页

作者： Guy Mtivier Jeffrey Rauch Institut de mathmatiques de Bordeaux Universit de Bordeaux department of mathematics University of Michigan

The profile equations of geometric optics are described in a form invariant under the natural transformations of first order systems of partial differential equations. This allows us to prove that various strategies for computing profile equations are equivalent. We prove that if L generates an evolution on L2 the same is true of the profile equations. We prove that the characteristic polynomial of the profile equations is the localization of the characteristic polynomial of the background operator at （y, dφ（y）） where φ is the background phase. We prove that the propagation cones of the profile equations are subsets of the propagation cones of the background operator.

关键词： geometric optics profile equation localisation vector bundles propagation cones

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ON A CHARACTERIZATION OF THE S-ESSENTIAL SPECTRA OF THE SUM AND THE PRODUCT OF TWO OPERATORS AND APPLICATION TO A TRANSPORT OPERATOR

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Acta mathematica Scientia 2015年第6期35卷 1285-1304页

作者： Salma CHARFI Sassia RAHALI Département de mathématiques Faculté des Sciences de Sfax Université de Sfax

In this paper, we develop some operational calculus inspired from the Fredholm operator theory to investigate the S-essential spectra of the sum and the product of two operators acting on a Banach space. Furthermore, we apply the obtained results to determine the S-essential spectra of an integro-differential operator with abstract boundary conditions in L1（[-a,a]×[-1,1]）（a〉0）.

关键词： Fredholm operator Fredholm perturbation S-essential spectra transport operator

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Grazing Pressure and Plant Functional Types in Puna Highlands,Northwestern Argentina

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Phyton-International Journal of Experimental Botany 2024年第5期93卷 1067-1080页

作者： Quiroga Mendiola Mariana Tálamo Andrés IPAF NOA—INTA(National Institute for Agricultural Technology) Posta de HornillosJujuy4622Argentina Facultad de Ciencias Naturales Universidad Nacional de SaltaSalta4400Argentina Instituto de Bio y Geociencias del NOA(IBIGEO) UNSa-CONICET.Laboratorio de Ecología Aplicada a la Conservación(LEAC)Facultad de Ciencias NaturalesUniversidad Nacional de SaltaSalta4400Argentina Maestría en Gestión Ambiental Escuela de NegociosUniversidad Católica de Salta(UCASAL)Salta4400Argentina

The Puna grasslands support grazing systems that produce meat and wool in multi-species herds,especially from llama(Lama glama)and ***,it is yet unknown whether grazing pressure can modify grassland structure and Plant Functional Types diversity and cover in Puna *** analyzed the relationship between grazing pressure and Plant Functional Types by comparing transects located near stockyards(high grazing pressure)and far from them(low pressure)and by evaluating the relationship between the Plant Functional Types cover to a Grazing Pressure Index(GPI).This index incorporates the heterogeneity of traditional pastoral *** two ecological sites(Ciénego and Tolar),we sampled paired transects(near-far).Plots near and far from corrals were similar in all the variables measured except for plots in Tolar,which tend to have higher total cover,possibly due to fecal fertilization near ***,we recorded an increase in total cover and grass cover at higher GPI in Ciénego,while in Tolar we found lower values of total cover and herbaceous dicotyledonous cover at intermediate intensities of *** only negative relationship found was the cover of clonal and non-clonal shrubs,possibly explained by the greater use of these shrubs as firewood near *** summary,our study does not show important changes in Plant Functional Types as a function of grazing pressure in the studied grasslands probably because grazing pressure is diluted or diminished when livestock rotates in different areas and grazing durations ***,the long grazing history with which the Puna has evolved could also contribute to the co-structuration between native vegetation and livestock farming.

关键词： Natural grasslands Puna herbivory ecological perturbation

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Morphological traits explain the individual position within resource-consumer networks of a Neotropical marsupial

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Current Zoology 2024年第4期70卷 453-464页

作者： Nicholas F.de Camargo Hernani F.M.de Oliveira Juliana F.Ribeiro Amabilio J.A.de Camargo Emerson M.Vieira Laboratorio de Ecologia de Vertebrados Departamento de EcologiaInstituto de Ciencias BiologicasUniversidade de BrasiliaCP 04457BrasiliaDF70910-900Brazil departamento de Zoologia Setor de Ciencias BiologicasUniversidade Federal do ParanaAvenida Coronel Francisco Heraclito dos Santos100CuritibaPR81531980Brazil Embrapa Cerrados Rodovia BR020km 18CP 08223PlanaltinaDE73310-970Brazil

Knowledge regarding the influence of individual traits on interaction patterns in nature can help understand the topological role of individuals within a network of intrapopulation *** tested hypotheses on the relationships between individuals'positions within networks(specialization and centrality)of 4 populations of the mouse opossum Gracilinanus agilis and their traits(i.e.,body length,body condition,tail length relative to body length,sex,reproductive condition,and botfly parasitism)and also seasonal effects in the Brazilian *** with lower body length,better body condition,and relatively shorter tail were more specialized(i.e.,less connected within the network).Individuals were also more specialized and less connected during the warm-wet *** relationship between individuals'position in the network and body traits,however,was independent of *** propose that specialization may arise not only as a result of preferred feed-ing strategies by more capable individuals(i.e.,those with better body condition and potentially prone to defend and access high-quality food resources)but alsobecause of morphological ***/younger individuals(consequently with less experience in foraging)and short-tailed individuals(less skilled to explore the vertical strata of the vegetation)would feed only on a subset of the available food resources and consequently become more ***,individuals are more specialized during the warm-wet season because of high competition(population-dense period)and higher ecological opportunities(resource-rich period).Therefore,our study reveals the relevance of individual traits inshaping interactionpatternsandspecialization inpopulations.

关键词： bodytraits centrality Cerrado Gracilinanus agilis seasonality specialization.

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