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Scolari F.,University of Pavia | Gomulski L.M.,University of Pavia | Ribeiro J.M.C.,National Institute of Allergy and Infectious Diseases | Siciliano P.,University of Pavia | And 13 more authors.

Background: Insect seminal fluid is a complex mixture of proteins, carbohydrates and lipids, produced in the male reproductive tract. This seminal fluid is transferred together with the spermatozoa during mating and induces post-mating changes in the female. Molecular characterization of seminal fluid proteins in the Mediterranean fruit fly, Ceratitis capitata, is limited, although studies suggest that some of these proteins are biologically active. Methodology/Principal Findings: We report on the functional annotation of 5914 high quality expressed sequence tags (ESTs) from the testes and male accessory glands, to identify transcripts encoding putative secreted peptides that might elicit post-mating responses in females. The ESTs were assembled into 3344 contigs, of which over 33% produced no hits against the nr database, and thus may represent novel or rapidly evolving sequences. Extraction of the coding sequences resulted in a total of 3371 putative peptides. The annotated dataset is available as a hyperlinked spreadsheet. Four hundred peptides were identified with putative secretory activity, including odorant binding proteins, protease inhibitor domain-containing peptides, antigen 5 proteins, mucins, and immunity-related sequences. Quantitative RT-PCR-based analyses of a subset of putative secretory protein-encoding transcripts from accessory glands indicated changes in their abundance after one or more copulations when compared to virgin males of the same age. These changes in abundance, particularly evident after the third mating, may be related to the requirement to replenish proteins to be transferred to the female. Conclusions/Significance: We have developed the first large-scale dataset for novel studies on functions and processes associated with the reproductive biology of Ceratitis capitata. The identified genes may help study genome evolution, in light of the high adaptive potential of the medfly. In addition, studies of male recovery dynamics in terms of accessory gland gene expression profiles and correlated remating inhibition mechanisms may permit the improvement of pest management approaches. Source

Angelillo M.,University of Salerno | Babilio E.,University of Naples Federico II | Fortunato A.,University of Salerno | Lippiello M.,University of Naples Federico II | Montanino A.,Istituto Universitario Of Studi Superiori Iuss
Mechanics of Materials

In the present paper we propose a new class of analytical solutions for the equilibrium problem of a prismatic sand pile under gravity, capturing the effects of the history of the sand pile formation on the stress distribution. The material is modeled as a continuum composed by a cohesionless granular material ruled by Coulomb friction, that is a material governed by the Mohr-Coulomb yield condition. The closure of the balance equations is obtained by considering a special restriction on stress, namely a special form of the stress tensor relative to a special curvilinear, locally non-orthogonal, reference system. This assumption generates a class of closed-form equilibrium solutions, depending on three parameters. By tuning the value of the parameters a family of equilibrium solutions is obtained, reproducing closely some published experimental data, and corresponding to different construction histories, namely, for example, the deposition from a line source and by uniform raining. The repertoire of equilibrated stress fields that we obtain in two special cases contains an approximation of the Incipient Failure Everywhere (IFE) solution and a closed-form description of the arching phenomenon. © 2016, Elsevier Ltd. All rights reserved. Source

Cangiani A.,University of Milan Bicocca | Gardini F.,University of Pavia | Manzini G.,CNR Institute for Applied Mathematics and Information Technologies | Manzini G.,Istituto Universitario Of Studi Superiori Iuss
Computer Methods in Applied Mechanics and Engineering

Optimal convergence rates for the mimetic finite difference method applied to eigenvalue problems in mixed form are proved. The analysis is based on a new a priori error bound for the source problem and relies on the existence of an appropriate elemental lifting of the mimetic discrete solution. Compared to the original convergence analysis of the method, the new a priori estimate does not require any extra regularity assumption on the right-hand side of the source problem. Numerical results confirming the optimal behavior of the method are presented. © 2010 Elsevier B.V. Source

Ceresa P.,European Center for Training and Research in Earthquake Engineering | Brezzi F.,Istituto Universitario Of Studi Superiori Iuss | Calvi G.M.,University of Pavia | Pinho R.,University of Pavia
Earthquake Engineering and Structural Dynamics

An analytical model, which aims at reproducing the response of a large-scale dynamic testing facility, that is a system composed of the specimen/shaking table/reaction-mass/airbags/dampers/soil is developed. The Lagrangian of the system is derived, under the assumption of large displacements and rotations. A set of four nonlinear differential equations is obtained and solved with numerical methods. Preliminary verifications of the derived model are carried out by reproducing both well-known results in the literature as well as those of a lumped model employed in the design of an existing dynamic testing facility. The case-study for validating the nonlinear equations of motion is the shaking table of the EUCENTRE Laboratory. © 2011 John Wiley & Sons, Ltd. Source

Pievani M.,Istituto Centro San Giovanni Of Dio | Filippini N.,University of Oxford | Van Den Heuvel M.P.,University Utrecht | Cappa S.F.,Istituto Universitario Of Studi Superiori Iuss | Frisoni G.B.,University of Geneva
Nature Reviews Neurology

Functional and structural connectivity measures, as assessed by means of functional and diffusion MRI, are emerging as potential intermediate biomarkers for Alzheimer disease (AD) and other disorders. This Review aims to summarize current evidence that connectivity biomarkers are associated with upstream and downstream disease processes (molecular pathology and clinical symptoms, respectively) in the major neurodegenerative diseases. The vast majority of studies have addressed functional and structural connectivity correlates of clinical phenotypes, confirming the predictable correlation with topography and disease severity in AD and frontotemporal dementia. In neurodegenerative diseases with motor symptoms, structural - but, to date, not functional - connectivity has been consistently found to be associated with clinical phenotype and disease severity. In the latest studies, the focus has moved towards the investigation of connectivity correlates of molecular pathology. Studies in cognitively healthy individuals with brain amyloidosis or genetic risk factors for AD have shown functional connectivity abnormalities in preclinical disease stages that are reminiscent of abnormalities observed in symptomatic AD. This shift in approach is promising, and may aid identification of early disease markers, establish a paradigm for other neurodegenerative disorders, shed light on the molecular neurobiology of connectivity disruption and, ultimately, clarify the pathophysiology of neurodegenerative diseases. © 2014 Macmillan Publishers Limited. All rights reserved. Source

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