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Geoscience Frontiers 2020年第1期11卷 167-188页

作者： andrea Festa Gianni Balestro Alessandro Borghi Sara De Caroli andrea Succo Dipartimento di Scienze della Terra Universitàdi TorinoTorinoItaly Dipartimento di Scienze Chimiche della Vita e della SostenibilitàAmbientaleUniversitàdi ParmaParmaItaly

The Canavese Zone(CZ)in the Western Alps represents the remnant of the distal passive margin of the Adria microplate,which was stretched and thinned during the Jurassic opening of the Alpine *** detailed geological mapping,stratigraphic and structural analyses,we document that the continental break-up of Pangea and tectonic dismemberment of the Adria distal margin,up to mantle rocks exhumation and oceanization,did not simply result from the syn-rift Jurassic extension but was strongly favored by older structu ral inheritances(the Proto-Canavese Shear Zone),which controlled earlier lithospheric *** findings allowed to redefine in detail(i)the tectono-stratigraphic setting of the Variscan metamorphic basement and the Late Carbonife rous to Early Cretaceous CZ succession,(ii)the role played by inherited Late Carboniferous to Early Triassic structures and(iii)the significance of the CZ in the geodynamic evolution of the Alpine *** large amount of extensional displacement and crustal thinning occurred during different pulses of Late Carbonife rous-Early Triassic strike-slip tectonics is wellconsistent with the role played by long-lived regional-scale wrench faults(e.g.,the East-Variscan Shear Zone),suggesting a re-discussion of models of mantle exhumation driven by low-angle detachment faults as unique efficient mechanism in stretching and thinning continental crust.

关键词： Alpine Tethys Western Alps Jurassic ophiolite Structural inheritance Continental break-up Mantle exhumation

Sperm priming response to perceived mating opportunities is reduced in male guppies with high baseline sperm production

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Current Zoology 2018年第2期64卷 205-211页

作者： Silvia CATTELAN andrea PILASTRO Department of Biology University of Padova Padova 35131 Italy

Producing sperm is costly and males have been selected to strategically adjust their sperm produc- tion and/or expenditure according to the fitness return associated with a specific mating. For exam- ple, males respond to fluctuations in the mating opportunities by adjusting the number of ＂ready＂ sperm. This phenomenon is known as ＂sperm priming＂ and is interpreted as a strategy to econo- mize the investment in sperm. The cost and benefits of the sperm priming response, however, are expected to depend on a male＇s baseline sperm production （BSP） in the absence of females, because of the different risk of sperm depletion and the nonlinearly increasing costs of sperm pro- duction. We tested this prediction in 2 replicated lines of male guppies Poecilia reticulata that were artificially selected for high and low BSP. BSP has a large genetic variance and a high sire heritabil- ity in guppies, and males respond to the perceived mating opportunities by increasing the number of ＂ready＂ sperm. We investigated whether males with a different BSP differed in their sperm pri- ming response. We found that when the perceived mating opportunities increased, males from low-sperm lines had a stronger sperm priming response than those from high-sperm lines. This result suggests that adaptive plasticity in sperm priming has the potential to evolve in response to different levels of BSP. The comparison between guppy populations with different levels of sperm production would allow to test whether the pattern reported here is also observed at the interpopulation level.

关键词： artificial selection mate availability Poecilia reticulata sperm investment sperm priming sperm production.

Rare horizontal transmission does not hide long-term inheritance of SINE highly conserved domains in the metazoan evolution

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Current Zoology 2016年第6期62卷 667-674页

作者： andrea LUCHETTI Barbara MANTOVANI Dipartimento di Scienze Biologiche Geologiche e Ambientali--Universit~ di Bologna Via Selmi 3 Bologna 40126Italy

Transposable elements （TEs） are self-replicating, mobile DNA sequences which constitute a significant fraction of eukaryotic genomes. They are generally considered selfish DNA, as their replication and random insertion may have deleterious effects on genome functionalities, although some beneficial effects and evolutionary potential have been recognized. Short interspersed elements （SINEs） are non-autonomous TEs with a modular structure： a small RNA-related head, a body, and a long interspersed element-related tail. Despite their high turnover rate and de novo emergence, the body may retain highly conserved domains （HCDs） shared among divergent SINE families： in metazoans, at least nine HCD-SINEs have been recognized. Data mining on public molecular databases allowed the retrieval of 16 new HCD-SINE families from cnidarian, molluscs, arthropods, and vertebrates. Tracking the ancestry of HCDs on the metazoan phylogeny revealed that some of them date back to the Radiata-Bilateria split. Moreover, phylogenetic and age versus divergence analyses of the most ancient HCDs suggested that long-term vertical inheritance is the rule, with few horizontal transfer events. We suggest that the evolutionary conservation of HCDs may be linked to their potential to serve as recombination hotspots. This indirectly affects host genomes by maintaining active and diverse SINE lineages, whose insertions may impact （either positively or negatively） on the evolution of the genome.

关键词： horizontal transfer Metazoan genome retrotransposons selfish DNA SINEs highly conserved domain vertica inheritance.

Approximation of the Spectral Fractional Powers of the Laplace-Beltrami Operator

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Numerical Mathematics(Theory,Methods and Applications) 2022年第4期15卷 1193-1218页

作者： andrea Bonito Wenyu Lei Department of Mathematics Texas A&M UniversityCollege StationTX 77843USA SISSA-International School for Advanced Studies Via Bonomea 26534136 TriesteItaly

We consider numerical approximation of spectral fractional Laplace-Beltrami problems on closed *** proposed numerical algorithms rely on their Balakrishnan integral representation and consists a sinc quadrature coupled with standard finite element methods for parametric *** up to a log term,optimal rate of convergence are observed and derived analytically when the discrepancies between the exact solution and its numerical approximations are measured in L^(2)and H^(1).The performances of the algorithms are illustrated on different settings including the approximation of Gaussian fields on surfaces.

关键词： Fractional diffusion Laplace-Beltrami FEM parametric methods on surfaces Gaussian fields

Abrupt variations of the radiolarian fauna at Mid-Pleistocene climate transition in the South China Sea

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Chinese Science Bulletin 2000年第10期45卷 952-955页

作者： andrea Abelmann Alfred Wegener Institute for Polar and Marine Research 27515 BremerhavenGermany

Based on a detailed study of the radiolarian fauna, the abundance pattern of planktic foraminifera as well as on isotope and sedimentological records, the Mid-Pleistocene climate transition as a multiple transition phenomenon could be recognized at Core 17957-2 from the South China Sea. Distinct changes in the radiolarian/foraminfera ratio, the coarse fraction and the radiolarian assemblages can be related to the global climate cooling observed at the Mid-Pleistocene revolution (MPR) around 900 ka. A pronounced southward shift of the North Equatorial Current that leads to lower sea-surface temperatures in the South China Sea is documented by the shift of tropical to subtropical radiolarian assemblages at 900 ka. Increasing radiolarian abundance after the MPR can be interpreted as a result of stronger upwelling and nutrient supply. These abrupt variations could result from the northern trade wind system and East Asian monsoon circulation.

关键词： radiolarian fauna abrupt variations 900 ka Mid-Pleistocene climate transition South China Sea.

Advanced methodologies for the cleaning of works of art

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Science China(Technological Sciences) 2023年第8期66卷 2162-2182页

作者： CASINI andrea CHELAZZI David BAGLIONI Piero CSGI and Department of Chemistry“Ugo Schiff” University of FlorenceSesto FiorentinoFlorence 50019Italy Department of Chemistry“Ugo Schiff”and CSGI University of FlorenceSesto FiorentinoFlorence 50019Italy

Cultural heritage assets constitute a fundamental socioeconomic resource,but the actual works of art need to be maintained,counteracting degradation processes,to transfer these benefits to future *** particular,the removal of soil,aged coatings,and vandalism/overpaints is one of the most needed interventions in art *** cleaning methodologies,based on classical solution and polymer chemistry,only grant limited control of the cleaning interventions,with the risk of affecting the original components of the artifacts,and often involving the use of toxic or non-environmentally friendly ***,materials science,colloids,and soft matter have provided valuable and safe solutions in the last *** review provides a selection of the most recent and advanced methodologies for the wet cleaning of works of art,spanning from nanostructured cleaning fluids(microemulsions,surfactants swollen micelles)to physical and chemical *** new methodologies work on different physico-chemical mechanisms,such as processes for detaching/dewetting,to selectively remove the unwanted layers in sustainable and cost-effective *** best performing systems,like microemulsions confined in“twin-chain”polyvinyl alcohol gels,have been assessed in the cleaning of masterpieces such as works by Pablo Picasso,Jackson Pollock and Roy *** attention is dedicated to“green”chemistry systems,using low-toxicity solvents or bio-based/waste materials to build gel ***,current trends and future perspectives are given,showing that advanced systems for art cleaning link with transversal fields of crucial importance even beyond Cultural heritage conservation,e.g.,detergency,tissue engineering,drug-delivery,food industry and cosmetics.

关键词： cleaning conservation cultural heritage gels microemulsions surfactants colloids nanoscience

Community Detection with the Weighted Parsimony Criterion

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Journal of Systems Science & Complexity 2015年第3期28卷 517-545页

作者： BETTINELLI andrea HANSEN Pierre LIBERTI Leo Dipartimento di Ingegneria dell’Energia Elettrica e Dell’Informazione Università di Bologna Viale del Risorgimento 2 40136 Bologna Italy Groupe d’études et de Recherche en Analyse des Décisions Hautes tudes Commerciales Montréal Canada LIX cole Polytechnique F-91128 Palaiseau France CNRS LIX Ecole Polytechnique 91128 Palaiseau France

Community detection in networks has been studied extensively in the last decade. Many criteria, expressing the quality of the partitions obtained, as well as a few exact algorithms and a large number of heuristics have been proposed. The parsimony criterion consists in minimizing the number of edges added or removed from the given network in order to transform it into a set of disjoint *** Zhang, Qiu and Zhang have proposed a weighted parsimony model in which a weight coefficient is introduced to balance the numbers of inserted and deleted edges. These authors propose rules to select a good value of the coefficient, use simulated annealing to find optimal or near-optimal solutions and solve a series of real and artificial instances. In the present paper, an algorithm is proposed for solving exactly the weighted parsimony problem for all values of the parameter. This algorithm is based on iteratively solving the problem for a set of given values of the parameter using a row generation algorithm. This procedure is combined with a search procedure to find all lowest breakpoints of the value curve(i.e., the weighted sum of inserted and deleted edges). Computational results on a series of artificial and real world networks from the literature are reported. It appears that several partitions for the same network may be informative and that the set of solutions usually contains at least one intuitively appealing partition.

关键词： Community detection complex networks parsimony.

Seismic displacement demand prediction in non-linear domain: Optimization of the N2 method

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Earthquake Engineering and Engineering Vibration 2019年第1期18卷 141-158页

作者： Lorenzo Diana andrea Manno Pierino Lestuzzi EPFL – ENAC – IIC – IMAC DEIB Politecnico di Milano

In Europe, computation of displacement demand for seismic assessment of existing buildings is essentially based on a simplified formulation of the N2 method as prescribed by Eurocode 8(EC8). However, a lack of accuracy of the N2 method in certain conditions has been pointed out by several studies. This paper addresses the assessment of effectiveness of the N2 method in seismic displacement demand determination in non-linear domain. The objective of this work is to investigate the accuracy of the N2 method through comparison with displacement demands computed using non-linear timehistory analysis(NLTHA). Results show that the original N2 method may lead to overestimation or underestimation of displacement demand predictions. This may affect results of mechanical model-based assessment of seismic vulnerability at an urban scale. Hence, the second part of this paper addresses an improvement of the N2 method formula by empirical evaluation of NLTHA results based on EC8 ground-classes. This task is formulated as a mathematical programming problem in which coefficients are obtained by minimizing the overall discrepancy between NLTHA and modified formula results. Various settings of the mathematical programming problem have been solved using a global optimization metaheuristic. An extensive comparison between the original N2 method formulation and optimized formulae highlights benefits of the strategy.

关键词： N2 method seismic vulnerability assessment non-linear time-history analysis spectrum compatible recordings displacement demand determination optimization strength reduction factor

Effect of grassland mosaic structure and dynamism on the reproductive habitat suitability for Alectoris graeca in central Apennines

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Journal of Mountain Science 2019年第12期16卷 2783-2792页

作者： andrea BRUSAFERRO Valentina IESARI Federico Maria TARDELLA Paola SCOCCO andrea CATORCI School of Biosciences and Veterinary Medicine University of Camerino

Over the last several decades,the Mediterranean region has been subjected to mountain abandonment and farming cessation,leading to changes in vegetation and coenological features of grasslands,contextually to the strong decline of the rock partridge(Alectoris graeca).Our hypothesis was that the ongoing dynamic processes leading to the compositional changes of grasslands in central Apennines affect the habitat suitability for the singing male(territorial male defending its reproductive site).In 2015,we defined the presence/absence of spring territorial singing males in seven sites(1,250-2,400 m a.s.l.),by the census in 74 playback stations,distributed along 15 *** characterized the topography and the vegetation mosaic of such sites according to the collected topographic and vegetation cover data in 59 randomly selected plots(100 m×100 m)along the *** understand the relations among the environmental variables and the effect of the composition and dynamism of the vegetation mosaics on the presence/absence of the singing male,we used principal components analysis and generalized linear mixed-effect *** results emphasized the marked overlap between the general environmental conditions,which proved to define the habitat suitability for ***,and the characteristics of the site chosen by the singing male for starting the reproductive ***,we found that the site suitability for the singing male decreases when the vegetation recovery processes are ongoing,because of the spread of coarse tall grassesdominated communities and/or grassland types with dense *** grass-dominated communities and thick-turf grasslands exert their negative effect decreasing the habitat suitability for the singing male starting from low cover ***,it is conceivable that singing male’s suitable habitat will be dramatically restricted to the steepest south-facing slopes,where topographic and soil conditions do not allow the spread of grassl

关键词： Brachypodium genuense Grazing cessation Reproductive habitat suitability Rock partridge Singing male Vegetation recovery processes

Transition Modelling Implications in the CFD Analysis of a Turbine Nozzle Vane Cascade Tested Over a Range of Mach and Reynolds Numbers

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Journal of Thermal Science 2015年第6期24卷 526-534页

作者： Michele Marconcini Roberto Pacciani andrea Arnone University of Florence Department of Industrial Engineering Via Santa Marta

The aerodynamic performance of a gas turbine nozzle vane cascade was investigated over a range of Mach and Reynolds *** work is part of a vast research project aimed at the analysis of fluid dynamics and heat transfer phenomena in cooled *** this paper computed results on the"solid vane"(without cooling devices)are presented and discussed in comparison with experimental *** measurements were provided by the University of Bergamo where the experimental campaign was carried out by means of a subsonic wind *** impact of boundary layer transition is investigated by using a novel laminar kinetic energy transport model and the widely used Langtry-Menterγ-Reθ,t *** comparison between calculations and measurements is presented in terms of blade loading distributions,total pressure loss coefficient contours downstream of the cascade,and velocity/turbulence-intensity profiles within the boundary layer at selected blade surface locations at *** will be shown how transitional calculations compare favorably with experiments.

关键词： Gas turbine CFD validation transition model secondary flows