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The impact of ancestral population size and incomplete lineage sorting on Bayesian estimation of species divergence times

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Current Zoology 2015年第5期61卷 874-885页

作者： Konstantinos ANGELIS mario DOS REIS Department of Genetics Evolution and Environment University College London Gower Street London WC 1E 6BT UK

Although the effects of the coalescent process on sequence divergence and genealogies are well understood, the vir- tual majority of studies that use molecular sequences to estimate times of divergence among species have failed to account for the coalescent process. Here we study the impact of ancestral population size and incomplete lineage sorting on Bayesian estimates of species divergence times under the molecular clock when the inference model ignores the coalescent process. Using a combination of mathematical analysis, computer simulations and analysis of real data, we find that the errors on estimates of times and the molecular rate can be substantial when ancestral populations are large and when there is substantial incomplete lineage sorting. For example, in a simple three-species case, we find that if the most precise fossil calibration is placed on the root of the phylogeny, the age of the internal node is overestimated, while if the most precise calibration is placed on the internal node, then the age of the root is underestimated. In both cases, the molecular rate is overestimated. Using simulations on a phylogeny of nine species, we show that substantial errors in time and rate estimates can be obtained even when dating ancient divergence events. We analyse the hominoid phylogeny and show that estimates of the neutral mutation rate obtained while ignoring the coalescent are too high. Using a coalescent-based technique to obtain geological times of divergence, we obtain estimates of the mutation rate that are within experimental estimates and we also obtain substantially older divergence times within the phylogeny [Current Zoology 61 （5）： 874-885, 2015].

关键词： Ancestral polymorphism Incomplete lineage sorting Divergence time estimation Gene tree Species tree

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Applying rock mass classifications to carbonate rocks for engineering purposes with a new approach using the rock engineering system

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第2期9卷 364-369页

作者： Gioacchino Francesco Andriani mario Parise Dipartimento di Scienze della Terra e Geoambientali Università degli Studi di Bari Aldo MoroVia E. Orabona n. 4Bari 70125Italy

Classical rock mass classification systems are not applicable to carbonate rocks,especially when these are affected by karst *** applications to such settings could therefore result in outcomes not representative of the real stress-strain *** this study,we propose a new classification of carbonate rock masses for engineering purposes,by adapting the rock engineering system(RES) method by Hudson for fractured and karstified rock masses,in order to highlight the problems of implementation of geomechanical models to carbonate *** new approach allows a less rigid classification for carbonate rock masses,taking into account the local properties of the outcrops,the site conditions and the type of engineering work as well.

关键词： Rock mass classification Carbonates Karst Rock engineering system(RES)

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Heterogeneous catalysis under flow for the 21st century fine chemical industry

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Green Energy & Environment 2021年第2期6卷 161-166页

作者： Rosaria Ciriminna mario Pagliaro Rafael Luque Istituto per Io Studio dei Mate riali Nanostnuturati CNRwia U.La Malfa 15390146PulemoItaly Deparamento de Quimica Orginica Univeridad de CordobaCampus de RabonalesEdificio Marie Curie(C-3)Cra Nnal IV-Akm 396Cordoba14014Spain Peoples Friendship University of Russia(RUDN Universiy) 6 Miklukho Maklaya St117198MoscowRussia

Due to metal leaching and poor catalyst stability, the chemical industry's fine chemical and pharmaceutical sectors have been historically reluctant to use supported transition metal catalysts to manufacture fine chemicals and active pharmaceutical ingredients. With the advent of new generation supported metal catalysts and flow chemistry, we argue in this study, this situation is poised to quickly change. Alongside heterogenized metal nanoparticles, both single-site molecular and single-atom catalyst will become ubiquitous. This study offers a critical outlook taking into account both technical and economic aspects.

关键词： Fine chemical Heterogeneous catalysis Single atom catalysis Green chemistry Chemical industry

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Both comorbidity burden and low testosterone can explain symptoms and signs of testosterone deficiency in men consulting for sexual dysfunction

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Asian Journal of Andrology 2020年第3期22卷 265-273页

作者： Giulia Rastrelli Giovanni Corona mario Maggi Sexual Medicine and Andrology Unit Department of Experimental and Clinical Biomedical SciencesUniversity of FlorenceViale Pieraccini 6Florence 50139Italy Endocrinology Unit Medical DepartmentMaggiore-Bellaria HospitalLargo Nigrisoli 2Bologna 40133Italy I.N.B.B. Biostructures and Biosystems National InstituteViale delle Medaglie d'Oro 305Rome(X)136Italy Endocrinology Unit Department of Experimental Clinical and Biomedical Sciences**Mario Serio"University of FlorenceViale Pieraccini 6Florence 50139Italy.

Low testosterone(T)is frequent in men with chronic *** clinical features of T deficiency(TD)overlap with those of chronic *** aim of this study is to evaluate the relative contribution of chronic disease score(CDS)and low T to the presenee of TD symptoms.A consecutive series of 3862 men(aged 52.1±13.1 years)consulting for sexual dysfunction were *** clinical and biochemical parameters were collected,in eluding the structured interview,ANDROTEST,for the assessme nt of TD *** color Doppler ultrasound(PCDU)was also *** on the medications taken,the CDS was *** a subset of 1687 men,information on mortality was collected(follow-up of 4.3±2.6 years).Higher CDS was associated with lower free and total T(TT)as well as with higher ANDROTEST *** introducing CDS and TT in multivariable models adjusted for age,severe erectile dysfunctio n and impaired morning erectio ns were associated with both CDS(odds ratio and 95%confide nee interaval,OR[95%Cl]=1.25[1.13;1.37]and 1.38[1.29;1.48],respectively)and low TT(OR[95%Cl]=1.11[1.00;1.23]and 1.13[1.06;1.21],respectively).Similar results were obtained for PCDU *** sexual desire was associated with low TT(OR[95%Cl]=1.21[1.13;1.30]),whereas it was inversely related with CDS(OR[95%Cl]=0.91[0.84;0.97]).When considering mortality for major cardiovascular events,TT<8 nmol I1,but not CDS,was a significant predictor(hazard ratio[95%Cl]=5.57[1.51;20.63]).Chronic illnesses are associated with an overt *** chronic diseases and low T can be invoIved in determining symptoms present in subjects complaining for sexual *** should be considered in the diagnostic workup for TD.

关键词： chronic diseases erectile dysfunction sexual symptoms testosterone deficiency

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Exosomes： multitask cargo carriers modulating innate mmunity to viruses

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Cellular & Molecular Immunology 2017年第5期14卷 476-477页

作者： mario U Mondelli Research Laboratories Department of InfectioutDiseases Fondazione IRCCS Policlinico SanMatteo and Department of Internal Medicin~and Therapeutics University of Pavia Pavi~27100 Italy /

Chronic infection with hepatitis B virus （HBV） is a major cause, ofcirrhosis and liver cancer worldwide. HBV is a smart DNA virus that replicates through an RNA intermediate. The viral genome translocates to the nucleus where it is converted into covalently closed circttlar DNA （cccDNA） serving as a template for viral transcription.

关键词： multitask cargo carriers innate immunity viruses

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Potential use of magnesium industrial waste for synthesis of Li and Mg co-doped LiMn_(2)O_(4)nanoparticles as cathode material for Li-ion batteries:Effect of sintering temperature

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Nano Research 2022年第5期15卷 4500-4516页

作者： Aleksei Llusco Luis Rojas Svetlana Ushak mario Grageda Department of Chemical Engineering and Mineral Processing and Center for Advanced Study of Lithium and Industrial Minerals(CELiMIN) Universidad de AntofagastaAntofagasta 1270300Chile

Potential advantages of active electrode nanomaterials have led to development of high energy and power density lithium-ion(Li-ion)***,under increasing demand for critical resources such as lithium and cobalt,it is necessary to use abundant raw materials,which can be obtained from industrial *** this work,purified Mg(OH)_(2)from waste generated in the production of Li2CO3 with natural brines from the Salar de Atacama(Chile)is used as a doping agent for synthesis of LiMn_(2)O_(4)(LMO)spinel octahedral nanoparticles co-doped with excess Li and *** of a pure cubic spinel phase(Fd3m)takes place at 500℃and sintering temperature effect at 580 and 750℃,thus the elemental composition and the structural,morphological,and electrochemical properties are studied in *** electrochemical performance at room temperature is obtained for Li_(1.03)Mg_(0.05)Mn_(1.92)O_(4)spinel sintered at 750℃with an initial discharge capacity of 121.3 mAh·g^(-1)and capacity retention of 94.0%after 100 cycles at C/3.A locally ordered spinel structure is obtained at 750℃,and doping with Mg^(2+)improves structural *** between both effects resulted in a high Li^(+)diffusion rate(1.29×10^(-9)cm^(2)·s^(-1))significantly improving cycling performance at elevated C-rates in 50℃.

关键词： LiMn_(2)O_(4)(LMO)spinel Mg doped excess Li octahedral nanoparticle industrial waste lithium-ion(Li-ion)batteries

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Fast Solvers of Fredholm Optimal Control Problems

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Numerical Mathematics(Theory,Methods and Applications) 2010年第4期3卷 431-448页

作者： mario Annunziato Alfio Borzi Universita degli Studi di Salerno Dipartimento di Matematica e InformaticaVia Ponte Don Melillo84084 Fisciano(SA)Italia Universita degli Studi del Sannio Dipartimento e Facolta di IngegneriaPalazzo Dell'Aquila Bosco LucarelliCorso Garibaldi 10782100 BeneventoItalia Institutfr Mathematik und Wissenschaftliches Rechnen Karl-Franzens-Universitt GrazHeinrichstr.368010 GrazAustria.

The formulation of optimal control problems governed by Fredholm integral equations of second kind and an efficient computational framework for solving these control problems is presented. Existence and uniqueness of optimal solutions is proved.A collective Gauss-Seidel scheme and a multigrid scheme are discussed. Optimal computational performance of these iterative schemes is proved by local Fourier analysis and demonstrated by results of numerical experiments.

关键词： Optimal control theory Fredholm integral equations of second kind iterative methods

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Telomere shortening is associated with corticosterone stress response in adult barn swallows

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Current Zoology 2022年第1期68卷 93-101页

作者： Alessandra costanzo Roberto AMBROSINI Marco PAROLINI Manuela CAPRIOLI Simona SECOMANDI Diego RUBOLINI Leonida FUSANI Virginie CANOINE Department of Environmental Science and Policy University of Milanvia Celoria 26I-20133 MilanItaly Department of Behavioral and Cognitive Biology University of ViennaAlthanstr.141090 ViennaAustria Konrad Lorenz Institute of Ethology University of Veterinary Medicine ViennaSavoyenstr.1a1160 ViennaAustria

When vertebrates face stressful events,the hypothalamic–pituitary–adrenal(HPA)axis is activated,generating a rapid increase in circulating glucocorticoid(GC)stress hormones followed by a return to baseline ***,repeated activation of HPA axis may lead to increase in oxidative *** target of oxidative stress is telomeres,nucleoprotein complexes at the end of chromosomes that shorten at each cell *** susceptibility of telomeres to oxidizing molecules has led to the hypothesis that increased GC levels boost telomere shortening,but studies on this link are *** studied if,in barn swallows Hirundo rustica,changes in adult erythrocyte telomere length between 2 consecutive breeding seasons are related to corticosterone(CORT)(the main avian GC)stress response induced by a standard capture-restraint ***-individual telomere length did not significantly change between consecutive breeding ***-year individuals showed the highest increase in circulating CORT concentrations following ***,we found a decline in female stress response along the breeding *** addition,telomere shortening covaried with the stress response:a delayed activation of the negative feedback loop terminating the stress response was associated with greater telomere ***,among-individual variation in stress response may affect telomere dynamics.

关键词： allostasis corticosterone Hirundo rustica stress response telomere

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Proper progression of neurogenesis relies on a defined pattern of SUMO-modified proteins

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Neural Regeneration Research 2022年第8期17卷 1731-1732页

作者： mario García-Domínguez Andalusian Centre for Molecular Biology and Regenerative Medicine-CABIMER CSIC-Universidad de Sevilla-Universidad Pablo de Olavide SevilleSpain

Neurogenesis is a complex process involving the orchestration of many transcription factors and other *** regulation of their activities is crucial for proper progression of neurogenesis.A few decades ago,covalent attachment of Small Ubiquitin-like MOdifier(SUMO)to other proteins was revealed as a major regulator of protein activities,constituting an essential posttranslational modification system in *** then,hundreds of proteins have been shown to be targets of SUMO,which is implicated in controlling many relevant processes in eukaryotic *** include the development and function of the nervous system,with SUMO tightly linked to synapsis and to neurodegenerative diseases(Yau et al.,2020).The SUMO protease SENP7 has been involved in neurogenesis(Juárez-Vicente et al.,2016),while sumoylation of BRAF35,a subunit of the LSD1 histone demethylase complex,assures the undifferentiated state of neural progenitors(Ceballos-Chávez et al.,2012).In addition,increased sumoylation in mouse brain-derived neural stem cells results in enhanced neuronal differentiation(Bernstock et al.,2019).

关键词： pattern diseases

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Simulation of temperature distribution and discharge crater of SiC_(p)/Al composites in a single-pulsed arc discharge

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Chinese Journal of Aeronautics 2021年第9期34卷 37-46页

作者： Jipeng CHEN Lin GU Wansheng ZHAO mario GUAGLIANO School of Mechanical and Electronic Engineering Nanjing Forestry UniversityNanjing 210037China State Key Laboratory of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Department of Mechanical Engineering Politecnico Di MilanoPiazza Leonardo da Vinci32Italy

SiC_(p)/Al composites are difficult-to-cut *** recent years,electrical arc discharge machining has been developed to improve the machinability of these ***,there is a big challenge to build a satisfactory heat transfer model of SiC_(p)/Al composites in the arc *** is not only because of the material property difference between the reinforcement and matrix material but also because of the micro-dimension Si C *** paper established a new heat conduction simulation model considering the Si C particle-Al matrix interface and the phase change effects in a single-pulsed arc discharge of SiC_(p)/Al composites.A novel Si C particle-Al matrix cell geometric model was designed ***,the temperature distribution at a different depth from the workpiece surface was analyzed,the influence of sic volume fraction on temperature field was studied,and the contribution of the interface thermal resistance and latent heat were *** demonstrate the validity of the new numerical model,comparisons and verifications were ***,the method of improving the model was proposed and the machining mechanism of arc discharge of SiC_(p)/Al matrix materials was *** was found that high temperature is prone to concentrate on the surface layers of the workpiece especially when the Si C fraction is high,also,the temperature fluctuates respectively at the evaporation point of aluminum and Si C,and the Si C-Al resistance has less influence on temperature distribution compared to latent heat,*** model build in this work improves the simulation accuracy observably compared to the previous model,and the simulation work will help to acquire a detailed mechanism of material removal of SiC_(p)/Al composites in the arc discharge machining.

关键词： Arc discharge Discharge crater SiC_(p)/Al composites Single-pulsed Temperature distribution

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