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Obligatory parthenogenesis and Te load： Bacillus stick insects and the R2 non-LTR retrotransposon

Insect Science 2017年第3期24卷 409-417页

作者： Livia Bonandin Claudia Scavariello Valentina Mingazzini Andrea Luchetti Barbara Mantovani dipartimento di scienze Biologiche Geologiche e Ambientali Universit~ di Bologna Bologna Italy

Transposable elements （Tes） are selfish genetic elements whose self-replication is contrasted by the host genome. In this context, host reproductive strategies are predicted to impact on both Tes load and activity. The presence and insertion distribution of the non- LTR retrotransposon R2 was here studied in populations of the strictly bisexual Bacillus grandii maretimi and of the obligatory parthenogenetic Bacillus atticus atticus. Further- more, data were also obtained from the offspring of selected B. a. atticus females. At the population level, the gonochoric B. g. maretimi showed a significantly higher R2 load than the obligatory parthenogenetic B. a. atticus. The comparison with bisexual and unisexual Bacillus rossius populations showed that their values were higher than those recorded for B. a. atticus and similar, or even higher, than those of B. g. maretimi. Consistently, an R2 load reduction is scored in B. a. atticus offspring even if with a great variance. On the whole, data here produced indicate that in the obligatory unisexual B. a. atticus R2 is active and that mechanisms of molecular turnover are effective. Furthermore, progeny analyses show that, at variance of the facultative parthenogenetic B. rossius, the R2 activ- ity is held at a lower rate. Modeling parental-offspring inheritance, suggests that in B. a. atticus recombination plays a major role in eliminating insertions rather than selection, as previously suggested for unisexual B. rossius progeny, even if in both cases a high variance is observed. In addition to this, mechanisms of R2 silencing or chances of clonal selection cannot be ruled out.

关键词： insertion activity Muller's ratchet Phasmida recombination retrotranspo-son unisexuality

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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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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.

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Optical absorption of （Ag-Au）133（SCH3）52 bimetallic monolayer-protected clusters

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Progress in Natural Science:Materials International 2016年第5期26卷 467-476页

作者： Alessandro Fortunelli Mauro Stener CNR-ICCOM Consiglio Nazionale delle Ricerche dipartimento di scienze chimiche e Farmaceutiche Università di Trieste

The evolution of the optical absorption spectrum of bimetallic Ag-Au monolayer-protected clusters（MPC）obtained by progressively doping Ag into the experimentally known structure of Au133（SR）52was predicted via rigorous time-dependent density-functional theory（TDDFT） calculations. In addition to monometallic Au133（SR）52and Ag133（SR）52species, 5 different（Ag-Au）133（SCH3）52homotops were considered with varying Ag content and site positioning, and their electronic structure and optical response were analyzed in terms of Projected Density Of States（PDOS）, the induced or transition electron density, and Transition Component Maps（TCM） at selected excitation energies. It was found that Ag doping led to the effects rather different from those encountered in bare metal clusters. And it was also observed that Ag doping could produce structured spectral features, especially in the 3–4 eV range but also in the optical region if Ag atoms were located in the sub-staple region, as rationalized by the accompanying electronic analysis. Additionally, Au doping into the staples of Ag-rich MPC also gave rise to a more homogeneous induced electron density. These findings show the great sensitivity of the electronic response of MPC nanoalloy systems to the exact location of the alloying sites.

关键词： Nanoalloys Gold nanomolecules electronic excited states Homotops Transition electron density

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Protective potential of glucagon like peptide 2(GLP-2) against the neurodegeneration

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Neural Regeneration Research 2019年第11期14卷 1901-1902页

作者： Antonella Amato Flavia Mulè dipartimento di scienze e Tecnologie Biologiche chimiche e Farmaceutiche (STeBICeF) Università di Palermo

Neurodegeneration consists in loss of neuron specific types, pattern and distribution, leading to progressive dysfunctions of the central nervous system. Neurodegenerative diseases include diverse pathological conditions, among which Alzheimer’s and Parkinson’s diseases are the most prevalent ones. Alzheimer’s disease is known as a growing dementia, characterized by progressive language, memory, and cognitive loss, while Parkinson’s disease is primarily characterized as a motor disorder. Senile plaques, caused by amyloid β peptide, hyperphosphorylated taubased neurofibrillary tangles and synapse loss, are the principal pathological hallmarks of Alzheimer’s disease.

关键词： Protective potential glucagon like peptide 2(GLP-2) neurodegeneration

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The role of structural inheritance in continental break-up and exhumation of Alpine Tethyan mantle(Canavese Zone,Western Alps)

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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

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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 *** being part of the same geological formation,these sandstones are characterized by highly different features in terms of texture and physico-mechanical *** 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 ***,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 *** this study,sandstone samples were collected from different sites and were analyzed at both the hand and thin section *** sandstone types were recognized,characterized by a different ***,the laboratory characterization allowed estimating their main physico-mechanical and ultrasonic properties,such as porosity,density,mechanical strength,deformability,and ultrasonic *** 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 *** 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 ***,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 *** 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 *** methodological approach developed for this research can be taken as reference to study other world

关键词： Sandstone Laboratory test Uniaxial Compressive Strength Porosity Rocks

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Complexation of As(Ⅲ)by phosphonate ligands in aqueous fluids:Thermodynamic behavior,chemical binding forms and sequestering abilities

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Journal of environmental Sciences 2020年第8期32卷 100-110页

作者： Donatella Chillè Donatella Aiello Giuseppa Ida Grasso Ottavia Giuffrè Anna Napoli Carmelo Sgarlata Claudia Foti dipartimento di scienze chimiche BiologicheFarmaceutiche ed AmbientaliUniversitàdi MessinaViale F.Stagno d’Alcontres 3198166 MessinaItaly dipartimento di Chimica e Tecnologie chimiche Universitàdella CalabriaVia P.Bucci87036 Arcavacata di Rende(CS)Italy dipartimento di scienze chimiche Universitàdegli Studi di CataniaViale A.Doria 695125 CataniaItaly

In recent years,the contamination of water by arsenic reached alarming levels in many countries of the world,attracting the interest of many researchers engaged in testing methodologies able to remove this harmful *** important aspect that must be taken into consideration is the possibility to find arsenic in different chemical forms which could require different approaches for its *** this aim,a speciation analysis appears to be crucial for better understanding the behavior of arsenic species in aqueous solutions,especially in presence of compounds with marked chelating *** can be identified as good sequestering agents and,at this purpose,this manuscript intends to investigate the interaction of As(Ⅲ)with three phosphonic acids derived from nitrilotriacetic acid(NTA)by replacements of one(N-(Phosphonomethyl)iminodiacetic acid,NTAP),two(N,N-Bis-(phosphonomethyl)glycine,NTA2P)and three(Nitrilotri(methylphosphonic acid),NTA3P)carboxylic groups with the same number of phosphonate *** in-depth potentiometric and calorimetric investigation allowed to determine speciation models featured by simple ML,MLH i and ML(OH)species.A complete thermodynamic characterization of the systems is reported together with the definition of coordination mode by mass spectrometry *** the light of the speciation models,the possibility of using these ligands in arsenic removal techniques was assessed by determining the pL 0.5(the concentration of ligand able to remove the 50%of metal ion present in trace).All ligands show a good sequestering ability,in particular under the conditions of fresh water,following the trend NTA3P>NTA2P>NTAP.

关键词： Phosphonate ligands Arsenic Thermodynamic interaction parameters Sequestering ability

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PeG-PLGA electrospun nanofibrous membranes loaded with Au@Fe2O3 nanoparticles for drug delivery applications

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Frontiers of physics 2018年第1期13卷 65-73页

作者： Salvatore Spadaro Marco Santoro Francesco Barreca Angela Scala Simona Grimato Fortunato Neri enza Fazio dipartimento di scienze Matematiche e Informatiche Scienze Fisiche e Scienze della Terra Universita di Messina Viale F. Stagno D'Alcontres 31 98166 Messina Italy dipartimento di scienze chimiche Biologiche Farmaceutiche e Ambientali Universita di Messina Viale F. Stagno D'Alcontres 31 98166 Messina Italy

A PeGylated-PLGA random nanofibrous membrane loaded with gold and iron oxide nanoparticles and with silibinin was prepared by electrospinning deposition. The nanofibrous membrane can be remotely controlled and activated by a laser light or magnetic field to release biological agents on demand. The nanosystems were characterized using scanning electron microscopy, Fourier transform infrared spectroscopy, nuclear magnetic resonance spectroscopy, and thermogravimetric analyses. The drug loading efficiency and drug content percentages were determined by UV-vis optical absorption spectroscopy. The nanofibrous membrane irradiated by a relatively low-intensity laser or stimulated by a magnetic field showed sustained silibinin release for at least 60 h, without the burst effect. The proposed low-cost electrospinning procedure is capable of assembling, via a one-step procedure, a stimuli-responsive drug-loaded nanosystem with metallic nanoparticles to be externally activated for controlled drug delivery.

关键词： Au@Fe2O3 nanoparticles PeG-PLGA copolymer pulsed laser ablation electrospinning,drug delivery

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Biofabrication of nanovesicles for brain diseases

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Neural Regeneration Research 2023年第3期18卷 525-526页

作者： Pasquale Picone Domenico Nuzzo Istituto per la Ricerca e l’Innovazione Biomedica CNRDipartimento di Scienze e Tecnologie Biologiche Chimiche e FarmaceuticheUniversitàdi PalermoPalermoItaly

Background:Nanotechnologies promise to improve disease diagnosis and treatment,overcoming the limitations of conventional *** particular,extracellular vesicles(eVs)and artificial vesicles(AVs)are strongly emerging tools in nanomedicine(Leggio et al.,2020).eVs are cell-derived membrane structures secreted after the fusion of endosomes with the plasma membrane(exosomes)or shed from the plasma membrane(microvesicles).eVs are released by different brain cells(neurons,oligodendrocytes,astrocytes,and microglia)and constitute a physiological intercellular communication ***,eVs can deliver different types of molecules(nucleic acids and proteins),which often influence the phenotype of the recipient *** play a physiological role in the central nervous system(CNS),such as development,myelination,regeneration,and synaptic activity(Lai et al.,2012).Due to their content,eVs could therefore constitute an important biomarker for neurodegenerative diseases,represent candidates for therapeutic use,enclosing regulatory molecules,or be considered as vectors for brain drug delivery(Croese et al.,2018).

关键词： diseases diagnosis constitute

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