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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

Polymerization of 1,3-Butadiene with Catalysts Based on Cobalt Dichloride Complexes with Aminophosphines: Switching the Regioselectivity by Varying the MAO/Co Molar Ratio

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Chinese Journal of Polymer Science 2024年第4期42卷 501-510页

作者： Giovanni Ricci Anna Sommazzi Francesco Masi Alessandra Forni CNR-Istituto di scienze e Tecnologie Molecolari“Giulio Natta”(SCITEC) via A.Corti 1220133MilanoItaly Viale Giovanni XXIII 34 I-28100NovaraNOItaly Via Galvani 7 I-26866Sant’Angelo LodigianoLOItaly CNR-Istituto di scienze e Tecnologie Molecolari“Giulio Natta”(SCITEC) via C.Golgi 1920133MilanoItaly

Several novel cobalt dichloride complexes with amino-phosphine bidentate ligands were synthesized and characterized.For some of them single crystals were obtained and their molecular structure was determined by X-ray diffraction method.All the complexes were then used in combination with MAO for the polymerization of 1,3-butadiene,obtaining polymers with different structures(i.e.,predominantly 1,2 or cis-1,4)mainly depending on the type of ligand and on the MAO/Co molar ratio.The behavior of these novel catalysts was compared with that exhibited,in the polymerization of the same monomer,by the systems CoCl_(2)(PR3)2-MAO and CoCl_(2)(PRPh2)2-MAO(R=alkyl or cycloalkyl group),and by the systems based on cobalt dichloride complexes with various bi-and tridentate ligands(e.g.,diphosphines,bis-imines,pyridyl-imines,bis-iminopyridines).The comparison between the different systems allowed us to make some clarity about the actual and effective role played by the various types of ligands in the polymerization of conjugated dienes with catalytic systems CoCl_(2)(L)-MAO,in which L=mono-,bi-,or tri-dentate ligand.

关键词： 1,3-Butadiene Stereospecific polymerization Cobalt catalysts Regioselectivity Aminophosphine ligands Crystal structures Chelate rings

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

Single-cell pan-omics, environmental neurology, and artificial intelligence:the time for holistic brain health research

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Neural Regeneration Research 2025年第6期 1703-1704页

作者： Paolo Abondio Francesco Bruno IRCCS Istituto delle scienze Neurologiche di Bologna Association for Neurogenetic Research (ARN) Lamezia Terme

The brain,with its trillions of neural connections,different cellular types,and molecular complexities,presents a formidable challenge for researchers aiming to comprehend the multifaceted nature of neural health.As traditional methods have provided valuable insights,emerging technologies offer unprecedented opportunities to delve deeper into the underpinnings of brain function.In the everevolving landscape of neuroscience,the quest to unravel the mysteries of the human brain is bound to take a leap forward thanks to new technological improvements and bold interpretative frameworks.

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Effects of positive end-expiratory pressure on intracranial pressure,cerebral perfusion pressure,and brain oxygenation in acute brain injury:Friend or foe?A scoping review

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Journal of Intensive Medicine 2024年第2期4卷 247-260页

作者： Greta Zunino Denise Battaglini Daniel Agustin Godoy IRCCS Ospedale Policlinico San Martino GenovaItaly dipartimento di scienze Diagnostiche e Chirurgiche Integrate Universitàdegli Studi di GenovaGenovaItaly Neurointensive Care Unit Sanatorio PasteurCatamarcaArgentina

Background Patients with acute brain injury(ABI)are a peculiar population because ABI does not only affect the brain but also other organs such as the lungs,as theorized in brain–lung crosstalk models.ABI patients often require mechanical ventilation(MV)to avoid the complications of impaired respiratory function that can follow ABI;MV should be settled with meticulousness owing to its effects on the intracranial compartment,especially regarding positive end-expiratory pressure(PEEP).This scoping review aimed to(1)describe the physiological basis and mechanisms related to the effects of PEEP in ABI;(2)examine how clinical research is conducted on this topic;(3)identify methods for setting PEEP in ABI;and(4)investigate the impact of the application of PEEP in ABI on the outcome.Methods The five-stage paradigm devised by Peters et al.and expanded by Arksey and O'Malley,Levac et al.,and the Joanna Briggs Institute was used for methodology.We also adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)extension criteria.Inclusion criteria:we compiled all scientific data from peer-reviewed journals and studies that discussed the application of PEEP and its impact on intracranial pressure,cerebral perfusion pressure,and brain oxygenation in adult patients with ABI.Exclusion criteria:studies that only examined a pediatric patient group(those under the age of 18),experiments conducted solely on animals;studies without intracranial pressure and/or cerebral perfusion pressure determinations,and studies with incomplete information.Two authors searched and screened for inclusion in papers published up to July 2023 using the PubMed-indexed online database.Data were presented in narrative and tubular form.Results The initial search yielded 330 references on the application of PEEP in ABI,of which 36 met our inclusion criteria.PEEP has recognized beneficial effects on gas exchange,but it produces hemodynamic changes that should be predicted to avoid undesired consequences on cerebral blood flow

关键词： Acute brain injury Mechanical ventilation Positive end-expiratory pressure Intracranial pressure Brain-lung crosstalk Multimodal monitoring

On Some Numerical Semigroup Transforms

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Algebra Colloquium 2022年第3期29卷 509-526页

作者： Carmelo Cisto Universita di Messina Dipartimento di Scienze Matematiche e Informatiche Scienze Fisiche e Scienze della TerraViale Ferdinando Stagno D'Alcontres 3198166 MessinaItaly

In this paper we introduce a particular semigroup transform A that fixes the invariants involved in Wilf's conjecture,except the embedding dimension.It also allows one to arrange the set of non-ordinary and non-irreducible numerical semigroups in a family of rooted trees.In addition,we study another transform,having similar features,that has been introduced by Bras-Amorós,and we make a comparison of them.In particular,we study the behavior of the embedding dimension under the action of such transforms,providing some consequences concerning Wilf's conjecture.

关键词： numerical semigroup embedding dimension genus left element Wilf's conjecture

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

Use of infrared thermography to detect reactions to stressful events:does animal personality matter?

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Integrative Zoology 2024年第2期19卷 224-239页

作者： Maria Vittoria MAZZAMUTO Marina MORANDINI William LAMPMAN Lucas Armand WAUTERS Damiano PREATONI John Lad KOPROWSKI Adriano MARTINOLI School of Natural Resources and Environment College of Agriculture and Life ScienceUniversity of ArizonaArizonaUSA Unitàdi Analisi e Gestione delle Risorse Ambientali Dipartimento di Scienze Teoriche e ApplicateGuido Tosi Research GroupUniversitàdegli Studi dell’InsubriaVareseItaly Haub School of Environment and Natural Resources University of WyomingWyomingUSA

The study of the relationship between animal stress and personality for free-ranging animals is limited and provides contrasting results.The perception of stressors by an individual may vary due to its personality,and certain personality traits may help individuals to better cope with them.Using non-invasive infrared thermography(IRT),we investigated the link between physiological and behavioral components expressed during an acute stress event by free-ranging Fremont’s squirrels(Tamiasciurus fremonti).We expected that,during the acute stress event of being approached by the researcher,individuals that showed a fast pace-of-life syndrome(bolder,more active,and less social/more aggressive)based on an arena test would exhibit stronger sympathetic-adrenal-medullary system reactivity showing a more intense stress-induced hyperthermia(high core body temperature and low peripheral temperature)than individuals with a slow pace of life(shy,less active,and more social).We successfully employed IRT technology to images of Fremont’s squirrels with identification of the individuals’body parts(eye,nose,ear,hind foot).However,we found no support for our hypothesis.Squirrels’body surface temperatures told us more about a squirrel’s external environment and less about the thermal state of the body in that environment following a stressful event.Further studies need to assess how to make IRT effective and efficient in the field and improve its performance in studying the relationships between physiology and personality in wildlife.

关键词： non-invasive method open field test physiology stress-induced hyperthermia Tamiasciurus fremonti

Introduction to the Special Issue on Recent Developments on Computational Biology-I

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2261-2264页

作者： Carlo Cattani Haci Mehmet Baskonus Armando Ciancio Engineering School(DEIM) University of TusciaViterbo01100Italy Department of Mathematics and Science Education Faculty of EducationHarran UniversitySanliurfa63190Turkey Universitàdegli Studi di Messina Dipartimento di Scienze BiomedicheOdontoiatriche e delle Immagini Morfologiche e FunzionaliMessina98122Italy

In modern time,experts started to use interdisciplinary properties with the development of technology and science.Thus,these disciplines provide more sophisticated properties of real-world problems.In this sense,some models need to be investigated by using revised and modified traditional methods.The first discipline is the applied sciences such as physics,engineering,mechanics,electricity,biology,economy and mathematical applications[1-5].In this stage,many methods[5-10]are developed and modified.To uncover the deep properties of problems is to use the main properties of such interdisciplinary properties.Furthermore,works conducted on such mathematical models including non-local operators,partial,ordinary and integer order have introduced a deeper investigation of problems for experts.By using technological tools,expertsmay observe more realistic and exact results of models.

关键词： properties. integer operators