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Interpreting siliciclastic sedimentation in the upper Paleozoic Mulargia-Escalaplano Basin(Sardinia, Italy):influence of tectonics on provenance

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Journal of Palaeogeography 2024年第1期13卷 18-34页

作者： Luca G.Costamagna Sara Criniti dipartimento di Scienze Chimiche e Geologiche Citadella UniversitariaBlocco A09042 Monserrato CAItaly dipartimento di Ingegneria dell'Ambiente Universita della Calabria87036 Arcavacata di Rende CSItaly

Late to post-Variscan molassic basins of Late Pennsylvanian-Permian age are exposed in Sardinia(Italy). Here, the compositional and stratigraphic evolution of the Mulargia-Escalaplano sedimentary basin(central Sardinia) has been investigated to highlight how the tectono-magmatic processes have influenced the sedimentation. Ruditic and arenitic samples were collected along well-characterized stratigraphic sections to provide a new insight into the impact of the tectono-magmatic processes on siliciclastic sedimentation. As a result, the conglomerates are mainly clast-supported, petromictic, and thus immature, with no defined maturity trend upwards. Nevertheless, pebble composition changes in times from Variscan basement pebble-rich to volcanic rock-rich, as a consequence of the basin widening and the dismantling and reworking of the coeval volcanic activity. The sandstone composition clearly changes from quartzolithic to feldspatholithic upwards, as a response to the same change of feeding and reworking of the volcanic rocks. Occasionally, interbedded quartzolithic arenites suggest exceptional floods carrying debris from the far borders of the basin. Also, the immature sandstone composition has been interpreted as being controlled by a continuous supply of fresh debris and to a rapid burial rate. In addition, the disappearance of metaradiolarite(lydite AA) Paleozoic grains in the sandstone mineral suite could represent a distinctive marker of a progressive unroofing of the Variscan chain and a clastic supply from deeper tectonic units.

关键词： Petrography Stratigraphy Provenance Molassic basins Sardinia

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On the Large-Scale Structure of the Universe as given by the Voronoi Diagrams

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Chinese Journal of Astronomy and Astrophysics 2006年第4期6卷 387-395页

作者： L. Zaninetti dipartimento di Fisica Generale

The size distributions of 2D and 3D Voronoi cells and of cells of Vp（2, 3）,--2D cut of 3D Voronoi diagram--are explored, with the slngle-parameter （re-scaled） gamma distribution playing a central role in the analytical fitting. Observational evidence for a cellular universe is briefly reviewed. A simulated Vp（2, 3） map with galaxies lying on the cell boundaries is constructed to compare, as regards general appearance, with the observed CfA map of galaxies and voids, the parameters of the simulation being so chosen as to reproduce the largest observed void size.

关键词： surveys -- galaxies clusters general -- （cosmology：） large-scale structure of Universe

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Continuous-time chaotic systems: Arbitrary full-state hybrid projective synchronization via a scalar signal

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Chinese Physics B 2013年第8期22卷 333-338页

作者： Giuseppe Grassi dipartimento Ingegneria Innovazione Universitàdel Salento-73100 LecceItaly

Relerrlng to contlnuous-Ume claaotlc systems, tills paper presents a new projective syncnromzatlon scheme, wnlcn enables each drive system state to be synchronized with a linear combination of response system states for any arbitrary scaling matrix. The proposed method, based on a structural condition related to the uncontrollable eigenvalues of the error system, can be applied to a wide class of continuous-time chaotic （hyperchaotic） systems and represents a general framework that includes any type of synchronization defined to date. An example involving a hyperchaotic oscillator is reported, with the aim of showing how a response system attractor is arbitrarily shaped using a scalar synchronizing signal only. Finally, it is shown that the recently introduced dislocated synchronization can be readily achieved using the conceived scheme.

关键词： continuous-time chaotic systems chaos synchronization observer-based synchronization scalarsynchronizing signal

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MIS 5e sea surface temperature estimation;a multi-proxy approach using a marine macrofossil assemblage(Mar Piccolo,Gulf of Taranto,Southern Italy)

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Journal of Palaeogeography 2024年第2期13卷 327-350页

作者： Pierluigi Santagati Edoardo Perri Maria Pia Bernasconi Mario Borrelli Salvatore Guerrieri Salvatore Critelli dipartimento di Biologia Ecologia e Scienze della TerraUniversita della Calabriavia Pietro Bucci87036 Arcavacata di RendeCosenzaItaly dipartimento di Ingegneria Ambientale Universita della Calabriavia Pietro Bucci87036 Arcavacata di RendeCosenzaItaly

It is reported a multi-proxy palaeoclimatic study conducted on a MIS 5e calcarenite from the Mar Piccolo Basin(MP),Gulf of Taranto(GT)(Central Mediterranean).The calcarenite returned a rich malacofauna consisting of 120 extant species,including four of the tropical Senegalese Fauna,today absent in the Mediterranean.The biogeographic-climatic affinity of the assemblage shows,compared to today,a double percentage of warm affinity species,while the cold affinity species are nearly equally represented,indicating a warmer but not strictly tropical SST.This is confirmed by the most recurring preferred SST ranges of the assemblage,indicating an average of 20℃.The skeletal compositions of five well-preserved molluscan and coral specimens were analyzed for trace elements and stable isotopes for further mean SST estimations.From the comparison of the results of several equations available in literature,it appears that only some SST estimations are realistic,converging into similar values of,on average,20.8±0.9℃.Considering all the used proxies,the MIS 5e SST difference compared to today falls in the range 1.2—2.0℃for the GT(being a more reasonable scenario)and 2.0—2.8℃for the MP.This is not a firmly tropical-like SST setting as suggested by the sole Senegalese fauna,indicating at least 2.7℃—3.5℃more than today’s GT and MP,respectively.The approximations and assumptions made for obtaining SST values with any single proxy indicate the need of a multi-proxy approach to define the best SST estimation.

关键词： MiS 5e Sea surface temperature Palaeoclimate proxy Fossil fauna Gulf of Taranto

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Ultra-highly sensitive dual gases detection based on photoacoustic spectroscopy by exploiting a long-wave,high-power,wide-tunable,singlelongitudinal-mode solid-state laser

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Light(Science & Applications) 2024年第5期13卷 941-956页

作者： Shunda Qiao Ying He Haiyue Sun Pietro Patimisco Angelo Sampaolo Vincenzo Spagnolo Yufei Ma National Key Laboratory of Laser Spatial Information Harbin Institute of TechnologyHarbinChina PolySense Lab Dipartimento Interateneo di FisicaUniversity and Politecnico of BariVia AmendolaBariItaly

Photoacoustic spectroscopy(PAS)as a highly sensitive and selective trace gas detection technique has extremely broad application in many fields.However,the laser sources currently used in PAS limit the sensing performance.Compared to diode laser and quantum cascade laser,the solid-state laser has the merits of high optical power,excellent beam quality,and wide tuning range.Here we present a long-wave,high-power,wide-tunable,singlelongitudinal-mode solid-state laser used as light source in a PAS sensor for trace gas detection.The self-built solid-state laser had an emission wavelength of~2μm with Tm:YAP crystal as the gain material,with an excellent wavelength and optical power stability as well as a high beam quality.The wide wavelength tuning range of 9.44 nm covers the absorption spectra of water and ammonia,with a maximum optical power of~130 mW,allowing dual gas detection with a single laser source.The solid-state laser was used as light source in three different photoacoustic detection techniques:standard PAS with microphone,and external-and intra-cavity quartz-enhanced photoacoustic spectroscopy(QEPAS),proving that solid-state laser is an attractive excitation source in photoacoustic spectroscopy.

关键词： power tunable tuning

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Statistical analysis of physico-mechanical parameters of sandstones occurring in orogenic settings

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Journal of Mountain Science 2024年第4期21卷 1388-1402页

作者： PAPPALARDO Giovanna CARBONE Serafina MONACO Carmelo ZOCCO Giordana MINEO Simone dipartimento Di Scienze Biologiche Geologiche E AmbientaliUniversitàDegli Studi Di CataniaCorso Italia 5795129 CataniaItaly

In northeastern Sicily(Italy),sandstone rock masses widely crop out as cover deposits over crystalline terrains belonging to the orogenic belt.Despite being part of the same geological formation,these sandstones are characterized by highly different features in terms of texture and physico-mechanical properties.This poses a scientific question on the possibility of tracing these rocks to a single statistical model,which could be representative of their main engineering geological properties.Therefore,it is worth investigating on the possible reasons of such differences,that should be searched either in the current geographical sandstone distribution or in the rock texture.For this study,sandstone samples were collected from different sites and were analyzed at both the hand and thin section scales.Three sandstone types were recognized,characterized by a different texture.Then,the laboratory characterization allowed estimating their main physico-mechanical and ultrasonic properties,such as porosity,density,mechanical strength,deformability,and ultrasonic velocities.The rock mechanical strength proved linked to the rock compactness and to the presence of lithic fragments,while pores and a pseudo-matrix between grains represent weakening features.Rock data were also statistically analyzed by grouping the specimens according to a geographical criterion,with respect to their sampling area,but no link was found between location and rock properties.Finally,with the aim of achieving mathematical laws that could be used to predict some rock properties from others,useful for practical purposes when dealing with such a high property variability,single and multiple regression analyses were carried out.Results show that the Uniaxial Compressive Strength,porosity,and P-wave velocity are the best predictors for a quick,indirect estimation of the main physico-mechanical parameters.The methodological approach developed for this research can be taken as reference to study other worldwide cases,involving rocks characterized by a wi

关键词： Sandstone Laboratory test Uniaxial Compressive Strength Porosity Rocks

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Product of the Schistosoma mansoni Glutathione Peroxidase Gene is a Selenium ContainingPhospholipid Hydroperoxide Glutathione Peroxidase (PHGPx) Sharing MolecularWeight and Substrate Specificity WithIts Mammalian Counterpart

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Biomedical and Environmental Sciences 1997年第2期10卷 209-213页

作者： MATILDE MAIORINO RAYMOND PIERCE AND LEOPOLD FLOHE (dipartimento di Chimica Biologica, Universitd di Padova, Padova, Italy Reltion hote-parasite stratigies vaccinales, INSERM U167, Institut Pasteur, Lille Cedex, France Department of Physiological Chemistr dipartimento di Chimica Biologica Università di Padova Italy.

In the blood fluke Schistosoma mansoni a functionally active, monomeric, phospholipid hydroperoxide glutathione peroxidase (PHGPx) has been purified and characterized. This enzyme contains a catalytically active selenocysteine. The protein has been shown to be the product of a cloned gene, previously referred to as a glutathione peroxidase gene. S. mansoni PHGPx has been found 5 times more abundant in female than in male worm extract. As in vertebrate PHGPx, homology alignment indicates that the residues involved in the glutathione binding by the tetrameric cellular glutathione peroxidase are mutated in the S. mansoni enzyme. Thus, this aspect appears a landmark of the PHGPx-type of glutathione peroxidases,which might be of functional relevance

关键词： Sharing MolecularWeight and Substrate Specificity WithIts Mammalian Counterpart Gene Product of the Schistosoma mansoni Glutathione Peroxidase Gene is a Selenium ContainingPhospholipid Hydroperoxide Glutathione Peroxidase PHGPx

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The potential for an old-growth forest to store carbon in the topsoil:A case study at Sasso Fratino,Italy

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Journal of Forestry Research 2024年第2期35卷 23-32页

作者： Tommaso Chiti Nicola Benilli Giovanni Mastrolonardo Giacomo Certini dipartimento per la Innovazione nei Sistemi Biologici Agroalimentari e Forestali(DIBAF)Universitàdella TusciaVia San C.de Lellis Snc01100 ViterboItaly dipartimento di Scienze e Tecnologie Agrarie AlimentariAmbientali e Forestali(DAGRI)Universitàdegli Studi di FirenzeP.le delle Cascine 1850144 FirenzeItaly

There is considerable interest devoted to oldgrowth forests and their capacity to store carbon(C)in biomass and soil.Inventories of C stocks in old-growth forests are carried out worldwide,although there is a lack of information on their actual potential for C sequestration.To further understand this,soil organic carbon(SOC)was measured in one of Italy's best-preserved old-growth forests,the Sasso Fratino Integral Nature Reserve.This reserve is on the World Heritage List along with other ancient beech forests of Europe,and it is virtually untouched due to the steepness of the terrain,even before legal constraints were imposed.Although the sandstone-derived soils are often shallow,they are rich in organic matter.However,no quantification had been carried out.By systematically sampling the topsoil across the forest,we accurately determined the average amount of SOC(62.0±16.9 Mg ha^(–1))and nitrogen(4.0±1.2 Mg ha^(–1))in the top 20 cm.Using the CENTURY model,future dynamics of SOC stocks were predicted to 2050 according to two climate scenarios,A1F1 and B2,the first of high concern and the second more optimistic.The model projected an increase of 0.2 and 0.3 Mg ha^(–1)a^(–1)by 2030 under the A1F1 and B2 scenarios,respectively,suggesting that the topsoil in old-growth forests does not reach equilibrium but continues accumulating SOC.However,from 2030 to 2050,a decline in SOC accumulation is predicted,indicating SOC net loss at high altitudes under the worst-case scenario.This study confirms that soils in oldgrowth forests play a significant role in carbon sequestration.It also suggests that climate change may affect the potential of these forests to store SOC not only in the long term but also in the coming years.

关键词： Carbon sequestration CENTURY model Climate change Forest soil Soil nitrogen

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Incoherent non-Hermitian skin effect in photonic quantum walks

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Light(Science & Applications) 2024年第5期13卷 885-893页

作者： Stefano Longhi dipartimento di Fisica Politecnico di MilanoPiazza L.da Vinci 32I-20133 MilanoItaly IFISC(UIB-CSIC) Instituto de Fisica Interdisciplinar y Sistemas ComplejosE-07122 Palma de MallorcaSpain

The non-Hermitian skin effect describes the concentration of an extensive number of eigenstates near the boundaries of certain dissipative systems.This phenomenon has raised a huge interest in different areas of physics,including photonics,deeply expanding our understanding of non-Hermitian systems and opening up new avenues in both fundamental and applied aspects of topological phenomena.The skin effect has been associated to a nontrivial pointgap spectral topology and has been experimentally demonstrated in a variety of synthetic matter systems,including photonic lattices.In most of physical models exhibiting the non-Hermitian skin effect full or partial wave coherence is generally assumed.Here we push the concept of skin effect into the fully incoherent regime and show that rather generally(but not universally)the non-Hermitian skin effect persists under dephasing dynamics.The results are illustrated by considering incoherent light dynamics in non-Hermitian photonic quantum walks.

关键词： dynamics. quantum effect

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Trajectory Attractors for Binary Fluid Mixtures in 3D

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Chinese Annals of Mathematics,Series B 2010年第5期31卷 655-678页

作者： Ciprian G.GAL Maurizio GRASSELLI Department of Mathematics University of Missouri dipartimento di Matematica "F. Brioschi" Politecnico di Milano

Two different models for the evolution of incompressible binary fluid mixtures in a three-dimensional bounded domain are considered.They consist of the 3D incompressible Navier-Stokes equations,subject to time-dependent external forces and coupled with either a convective Allen-Cahn or Cahn-Hilliard equation.Such systems can be viewed as generalizations of the Navier-Stokes equations to two-phase fluids.Using the trajectory approach,the authors prove the existence of the trajectory attractor for both systems.

关键词：流体混合物三维轨迹吸引子 Stokes方程二元不可压缩流体演化时间依赖

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