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Analysis of Strehl ratio limit with superresolution binary phase filters

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chinese Optics Letters 2016年第7期14卷 38-41页

作者： vidal F.canales Pedro J.Valle Manuel P.cagigal Departamento de física Aplicada Universidad de CantabriaSantander 39005Spain

Several pupil filtering techniques have been developed in the last few years to obtain transverse superresolution （a narrower point spread function core）. Such a core decrease entails two relevant limitations： a decrease of the peak intensity and an increase of the sidelobe intensity. Here, we calculate the Strehl ratio as a function of the core size for the most used binary phase filters. Furthermore, we show that this relation approaches the fundamental limit of the attainable Strehl ratio at the focal plane for any filter. Finally, we show the calculation of the peak-to-sidelobe ratio in order to check the system viability in every application.

关键词： Analysis of Strehl ratio limit with superresolution binary phase filters

Kinetic Slip Boundary condition for Isothermal Rarefied Gas Flows through Static Non-Planar Geometries Based on the Regularized Lattice-Boltzmann Method

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communications in computational Physics 2022年第3期31卷 816-868页

作者： Jean-Michel Tucny David vidal Sebastien Leclaire Francois Bertrand Mechanical Engineering Department Polytechnique MontralP.O.Box 6079Stn.CVMontrealQCCANADAH3C 3A7 chemical Engineering Department Polytechnique MontralP.O.Box 6079Stn.CVMontrealQCCANADAH3C 3A7

The simulation of rarefied gasflows through complex porous media is chal-lenging due to the tortuousflow pathways inherent to such *** Lattice Boltzmann method(LBM)has been identified as a promising avenue to solveflows through complex geometries due to the simplicity of its scheme and its high parallel computational *** has been proposed to model the stress-strain relationship with the extended Navier-Stokes equations rather than attempting to directly solve the Boltzmann ***,a regularization technique is required tofilter out non-resolved higher-order components with a low-order velocity *** slip boundary conditions(Bcs)have been proposed for the non-regularized multiple relaxation time LBM(MRT-LBM)for planar geometries,previous slip Bcs have never been verified extensively with the regularization *** this work,following an extensive literature review on the imposition of slip Bcs for rarefiedflows with the LBM,it is proven that earlier values for kinetic parameters developed to impose slip Bcs are inaccurate for the regularized MRT-LBM and differ between the D2Q9 and D3Q15 *** error was eliminated for planarflows and good agreement be-tween analytical solutions for arrays of cylinders and spheres was found with a wide range of Knudsen numbers.

关键词： Lattice Boltzmann method(LBM) boundary condition(Bc) rarefiedflow nonplanar geometry

Optimization of room-and-pillar dimensions using automated numerical models

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International Journal of Mining Science and Technology 2019年第5期29卷 797-801页

作者： Gian Franco Napa-García Tais Renata camara vidal Félix Navarro Torres Mining Instituto Tecnológico ValeSanta LuziaMG 33040-900Brazil Exploration and Mineral Projects VALE S.A.Santa LuziaMG 33040-900Brazil

This paper presents an optimization methodology for the geometric configuration of a room–and–pillar mining project,considering safety and operational restrictions while maximizing ore *** underground manganese mine was chosen as a case study to investigate the capabilities of the presented methodology.A software package(OPTIMINE)was implemented to address the computational demand in an automated ***–dimensional finite difference analyses were performed in FLAc3D and used as implicit functions to consider safety in terms of the factor of safety and room *** obtained results showed that recovery could be increased from 44%to more than 80%in a safe manner.

关键词： Optimization Safety Room and pillar mining Ore recovery 3D numerical modeling

A comprehensive analysis of chromosomal anomalies in metaphase II spermatocytes from infertile patients

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Asian Journal of Andrology 2018年第1期20卷 105-106页

作者： Zaida Sarrate Joan Blanco Oliver Valero Francesca vidal Genetics of Male Fertility Group Unitat de Biologia Cel.lular Departament de Biologia Cel.lular Fisiologia i Immunologia Facultat de Biociencies Universitat Autonoma de Barcelona Bellaterra (Cerdanyola del Valles) 08193 Spain Servei d'Estadistica Aplicada Universitat Autonoma de Barcelona Bellaterra (Cerdanyola del Valles) 08193 Spain

Dear Editor, The scarce number of secondary spermatocytes in human seminiferous tubules and the complexity of analyzing chromosomes at metaphase II are the main causes of the limited knowledge we have about chromosome characteristics at this stage. In this study, we have performed a comprehensive analysis of meiotic abnormalities in metaphase II spermatocytes combining Leishman＇s staining protocols and multiplex fluorescent in situ hybridization procedures. Results indicated that infertile individuals showed different susceptibilities to meiotic abnormalities in secondary spermatocytes without a preferentially effect on any particular chromosome.

关键词： MEIOTIc ABNORMALITIES SISTER cHROMATIDS ANEUPloIDY MEIOSIS SEPARATION OOcYTES MALES

Orogenic Movements during the Paleozoic Period: Development of the Granitoid Formations in the Northwestern Region of Spain’s Iberian Peninsula

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Journal of Earth Science 2020年第3期31卷 611-620页

作者： Juan Ramon vidal Romani Zhaojun Song Huimin Liu Yifang Sun Haonan Li college of Earth Science and Engineering Shandong University of Science and TechnologyQingdao 266590China University Institute of Geology University of CorunnaGalicia 15071Spain Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and Technology、Qingdao 266061China

In the present study,Paleozoic Variscan orogenesis was a model of the oroclinal flexion accompanied by extensive magmatism,which could be divided into the following two types:post-tectonic and syn-tectonic tonalite granite,and leuco-granite which were controlled by the tectonic characteristics of the *** was observed that a very high majority of the samples had displayed discontinuities in their structures,that were later utilized to define the granitoid morphology and development characteristics of the rock during the intrusion ***,it was determined that the tectonics associated with the Alpine orogeny results in the new generation of faults and fractures during the Paleogene Period had produced the development of the *** to different weathering processes,the depressions which had resulted in the present granitoid reliefs were found to be exclusively related to the structural development processes during the geological history(either tectonic or magmatic)of the granite,and not as normally interpreted.

关键词： granitoid geomorphology endogenous forms exogenous forms intrusive structures

Invasive rats strengthen predation pressure on bird eggs in a South Pacific island rainforest

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current Zoology 2017年第6期63卷 583-590页

作者： Quiterie DURON Edouard BOURGUET Helene DE MERINGO Alexandre MILloN Eric vidal Institut Mediterraneen de Biodiversite et d'Ecologie Marine et continentale (IMBE) Aix Marseille Universite CNRS IRD Avignon Universite Centre IRD Noumea - BP A5 98848 Noumea Cedex Nouvelle-Caledonie France Institut Mediterraneen de Biodiversite et d'Ecologie Marine et continentale (IMBE) Aix Marseille Universite CNRS IRD Avignon Universite Technopole Arbois-Mediterranee Bat. Villemin - BP 80 F-13545 Aix-en-Provence cedex 04 France

Invasive rats （Rattus spp.） are known to have pervasive impacts on island birds, particularly on their nesting success. To conserve or restore bird populations, numerous invasive rat control or eradication projects are undertaken on islands worldwide. However, such projects represent a huge investment and the decision-making process requires proper assessment of rat impacts. Here, we assessed the influence of two sympatric invasive rats （Rattus rattus and R. exulans） on native bird eggs in a New caledonian rainforest, using artificial bird-nest monitoring. A total of 178 artificial nests containing two eggs of three different sizes were placed either on the ground or 1.5 m high and monitored at the start of the birds＇ breeding season. Overall, 12.4% of the nests were depredated during the first 7 days. At site 1, where nests were monitored during 16 days, 41.8% of the nests were depredated. The main predator was the native crow corvus moneduloides, responsible for 62.9% of the overall predation events. Rats were responsible for only 22.9% of the events, and ate only small and medium eggs at both heights. Our experiment suggests that in New caledonia, predation pressure by rats strengthens overall bird-nest predation, adding to that by native predators, Experimental rat control operations may allow reduced predation pressure on nests as well as the recording of biodiversity responses after rat population reduction.

关键词： bird-nest predation forest birds invasive rodents island conservation rat management.

Therapeutic potential of insulin-like growth factor 2 in Huntington's disease: controlling proteostasis to alleviate the load of misfolded protein

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Neural Regeneration Research 2021年第8期16卷 1564-1565页

作者： Paulina Troncoso-Escudero claudio Hetz Rene L.vidal Biomedical Neuroscience Institute Faculty of MedicineUniversity of ChileSantiagoChile center for Geroscience Brain Health and MetabolismSantiagoChile Program of cellular and Molecular Biology Institute of Biomedical SciencesUniversity of ChileSantiagoChile center for Integrative Biology Faculty of SciencesUniversity MayorChile Buck Institute for Research on Aging NovatoCAUSA

Huntington's disease(HD) is an inherited autosomal dominant neurodegenerative disorder characterized by the development of adult-onset motor dysfunction,psychiatric disturbances and intellectual *** is associated with an expansion of cAG repeat sequence in the huntingtin gene(Htt).Exon 1 of Htt normally contains between 6 to 35 cAG repeats,whereas in patients affected with HD it contains more than 40 trinucleotides.

关键词： Huntington Therapeutic stasis

Evolutionary importance of the relationship between cytogeography and climate:New insights on creosote bushes from North and South America

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Plant Diversity 2022年第5期44卷 492-498页

作者： Romina vidal-Russell Mariana Tadey Romana Urfusova Tomás Urfus cintia Paola Souto Laboratorio Ecotono-INIBIOMA(cONIcET-UNcomahue) Quintral1250BarilocheRío NegroArgentina Department of Botany Faculty of ScienceCharles UniversityBenátská212800PragueCzech Republic

Relationships between genome size and environmental variables suggest that DNA content might be adaptive and of evolutionary importance in *** genus Larrea provides an interesting system to test this hypothesis,since it shows both intra-and interspecific variation in genome *** has an amphitropical distribution in North and South American deserts,where it is most *** tridentata in North America shows a gradient of increasing autopolyploidy;while three of the four studied South American species are diploids,Larrea divaricata,Larrea nitida,Larrea ameghinoi,and the fourth is an allopolyploid,Larrea *** downloaded available focal species’georeferenced records from seven data *** used these records to extract biologically relevant environmental variables from Worldclim at 30 arc seconds scale,to have a broad characterization of the variable climatic conditions of both regions,and a climatic envelope for each *** estimated relative DNA content index and relative monoploid genome values,by flow cytometry,of four most abundant Larrea species throughout their respective *** we winnow the bioclimatic dataset down to uncorrelated variables and sampled locales,to analyse the degree of association between both intra-and interspecific relative DNA content and climatic variables that are functionally relevant in arid environments using Pearson correlations,general linear and mixed effects *** the genus Larrea,relative DNA content increases with rising temperature and decreases with rising *** the intraspecific level,all four species show relative DNA content variation across climatic *** is a genus that shows genome size variation correlated with *** results are also consistent with the hypothesis that extreme environmental pressures may have facilitated repeated whole genome duplication events in North America,while in South America,reticulate evolution,as allopolyploidizati

关键词： DNA content Drylands Genome size Jarilla Larrea Zygophyllaceae

The Role of Phosphorylation in Redox Regulation of Photosynthesis Genes psaA and psbA during Photosynthetic Acclimation of Mustard

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Molecular Plant 2009年第3期2卷 416-429页

作者： Sebastian Steiner Lars Dietzel Yvonne Schroter vidal Fey Raik Wagner Thomas Pfannschmidt Junior Research Group 'Plant acclimation to environmental changes: Protein analysis by MS' at the Institute of General Botany and Plant Physiology Department of Plant Physiology Friedrich-Schiller-University of Jena Dornburger Str. 159 07743 Jena Germany Present address: VTT Technical research center of Finland Medical Biotechnology Turku Finland Present address: Department of chemistry Bioenergetics University of Umea Sweden

The long-term response （LTR） to light-quality gradients improves performance and survival of plants in dense stands. It involves redox-controlled transcriptional regulation of the plastome-encoded genes psaAB （encoding the P700 apoproteins of photosystem I） and psbA （encoding the D1 protein of photosystem II） and requires the action of plastidlocalized kinases. To study the potential impact of phosphorylation events on plastid gene expression during the LTR, we analyzed mustard seedlings acclimated to light sources favoring either photosystem I or photosystem II. Primer extension analyses of psaA transcripts indicate that the redox regulation occurs at the principal bacterial promoters, suggesting that the plastid encoded RNA polymerase （PEP） is the target for redox signals. chloroplast protein fractions containing PEP and other DNA-binding proteins were purified from mustard via heparin-Sepharose chromatography. The biochemical properties of these fractions were analyzed with special emphasis on promoter recognition and specificity, phosphorylation state, and kinase activity. The results demonstrate that the LTR involves the action of small DNA-binding proteins; three of them exhibit specific changes in the phosphorylation state. Auto-phosphorylation assays, in addition, exhibit large differences in the activity of endogenous kinase activities. chloroplast run-on transcription experiments with the kinase inhibitor H7 and the reductant DTT indicate that phosphorylation events are essential for the mediation of redox signals toward psaA and psbA transcription initiation, but require the synergistic action of a thiol redox signal. The data support the idea that redox signals from the thylakoid membrane are linked to gene expression via phosphorylation events; however, this mediation appears to require a complex network of interacting proteins rather than a simple phosphorelay.

关键词： Light-quality acclimation redox control protein phosphorylation chloroplast transcription Sinapis alba.