Long-term physical evolution of an elastomeric ultrasound contrast microbubble

Hypothesis: One of the main assets of crosslinked polymer-shelled microbubbles (MBs) as ultrasound-active theranostic agents is the robustness of the shells, combined with the chemical versatility in modifying the surface with ligands and/or drugs. Despite the long shelf-life, subtle modifications occur in the MB shells involving shifts in acoustic, mechanical and structural properties. Experiments: We carried out a long-term morphological and acoustic evolution analysis on elastomeric polyvinyl-alcohol (PVA)-shelled MBs, a novel platform accomplishing good acoustic and surface performances in one agent. Confocal laser scanning microscopy, acoustic spectroscopy and AFM nanomechanics were integrated to understand the mechanism of PVA MBs ageing. The changes in the MB acoustic properties were framed in terms of shell thickness and viscoelasticity using a linearised oscillation theory, and compared to MB morphology and to nanomechanical analysis. Findings: We enlightened a novel, intriguing ageing time evolution of the PVA MBs with double behaviour with respect to a crossover time of ∼50 days. Before, significant changes occur in MB stiffness and shell thickness, mainly due to a massive release of entangled PVA chains. Then, the MB resonance frequency increases together with shell thickening and softening. Our benchmark study is of general interest for emerging viscoelastomeric bubbles towards personalised medicine

Personal private herbaria: a valuable but neglected source of floristic data. The case of Italian collections today

Today private collections still represent an important source of information as is evident from the available literature, where, in many cases, private collections are mentioned both in floristic and taxonomic/systematic researches. We present a summary of the main information about private herbaria in Italy, whose collections are currently increasing. Based on our survey, we retrieved information on 34 personal herbaria where 156,361 specimens are preserved at present. Piedmont and Tuscany resulted the two Italian regions with the highest number of collections, whereas for 9 regions we obtained no answer. The most represented families resulted Asteraceae and Poaceae, whereas the most represented genera resulted Carex, Trifolium, and Hieracium. Taken all together, these collections rank 16th among the 68 institutional public herbaria officially recognised in Italy

Correlated Component Analysis for diffuse component separation with error estimation on simulated Planck polarization data

We present a data analysis pipeline for CMB polarization experiments, running from multi-frequency maps to the power spectra. We focus mainly on component separation and, for the first time, we work out the covariance matrix accounting for errors associated to the separation itself. This allows us to propagate such errors and evaluate their contributions to the uncertainties on the final products.The pipeline is optimized for intermediate and small scales, but could be easily extended to lower multipoles. We exploit realistic simulations of the sky, tailored for the Planck mission. The component separation is achieved by exploiting the Correlated Component Analysis in the harmonic domain, that we demonstrate to be superior to the real-space application (Bonaldi et al. 2006). We present two techniques to estimate the uncertainties on the spectral parameters of the separated components. The component separation errors are then propagated by means of Monte Carlo simulations to obtain the corresponding contributions to uncertainties on the component maps and on the CMB power spectra. For the Planck polarization case they are found to be subdominant compared to noise.Comment: 17 pages, accepted in MNRA

A tree-decomposed transfer matrix for computing exact Potts model partition functions for arbitrary graphs, with applications to planar graph colourings

Combining tree decomposition and transfer matrix techniques provides a very general algorithm for computing exact partition functions of statistical models defined on arbitrary graphs. The algorithm is particularly efficient in the case of planar graphs. We illustrate it by computing the Potts model partition functions and chromatic polynomials (the number of proper vertex colourings using Q colours) for large samples of random planar graphs with up to N=100 vertices. In the latter case, our algorithm yields a sub-exponential average running time of ~ exp(1.516 sqrt(N)), a substantial improvement over the exponential running time ~ exp(0.245 N) provided by the hitherto best known algorithm. We study the statistics of chromatic roots of random planar graphs in some detail, comparing the findings with results for finite pieces of a regular lattice.Comment: 5 pages, 3 figures. Version 2 has been substantially expanded. Version 3 shows that the worst-case running time is sub-exponential in the number of vertice

LOS COSTOS DE LA NO CALIDAD EN PROYECTOS IT

RESUMEN.Un acto de Calidad, cualquiera que este sea, implica una decisión, una oportunidad de elegir un beneficioesperado, sea consciente o inconsciente. Esta oportunidad implica un costo que se traduce en una inversióndeterminada si es un beneficio; se traduce en un gasto si no implica algún beneficio, convirtiéndose en uncosto de no calidad. Cada empresa tiene que decidir que costo es el más conveniente. Los costos totalesrelacionados con la calidad son la suma de los costos de calidad y los costos de la no calidad.PALABRAS CLAVES (KEYWORDS)No calidadInnovación TecnológicaMedició

Las Variables de Costos de Calidad en Proye tos de Tecnologia de Informacion (IT)

Un a to de Calidad, ualquiera que este sea, impli a una de ision, una oportunidad de elegir un bene io esperado, sea ons iente o in ons iente

Ultrasound delivery of Surface Enhanced InfraRed Absorption active gold-nanoprobes into fibroblast cells: a biological study via Synchrotron-based InfraRed microanalysis at single cell level

Ultrasound (US) induced transient membrane permeabilisation has emerged as a hugely promising tool for the delivery of exogenous vectors through the cytoplasmic membrane, paving the way to the design of novel anticancer strategies by targeting functional nanomaterials to specific biological sites. An essential step towards this end is the detailed recognition of suitably marked nanoparticles in sonoporated cells and the investigation of the potential related biological effects. By taking advantage of Synchrotron Radiation fourier transform infrared micro-spectroscopy (SR-microftiR) in providing highly sensitive analysis at the single cell level, we studied the internalisation of a nanoprobe within fibroblasts (NIH-3T3) promoted by low-intensity US. To this aim we employed 20 nm gold nanoparticles conjugated with the IR marker 4-aminothiophenol. The significant Surface Enhanced Infrared Absorption provided by the nanoprobes, with an absorbance increase up to two orders of magnitude, allowed us to efficiently recognise their inclusion within cells. Notably, the selective and stable SR- microftiR detection from single cells that have internalised the nanoprobe exhibited clear changes in both shape and intensity of the spectral profile, highlighting the occurrence of biological effects. Flow cytometry, immunofluorescence and murine cytokinesis-block micronucleus assays confirmed the presence of slight but significant cytotoxic and genotoxic events associated with the US-nanoprobe combined treatments. our results can provide novel hints towards US and nanomedicine combined strategies for cell spectral imaging as well as drug delivery-based therapies

Chromosome numbers for the Italian flora: 9

In this contribution, new chromosome data obtained on material collected in Italy are presented. It includes counts from six populations of three taxa within the genus Pulmonaria, two of which are endemic to Italy (P. vallarsae subsp. apennina and P. vallarsae subsp. vallarsae); the other is the widespread European P. officinalis. In addition, two counts from Potentilla detommasii and Stachys thirkei, two eastern Mediterranean species, are also reported

Differential effects on membrane permeability and viability of human keratinocyte cells undergoing very low intensity megasonic fields

Among different therapeutic applications of Ultrasound (US), transient membrane sonoporation (SP) - a temporary, non-lethal porosity, mechanically induced in cell membranes through US exposure - represents a compelling opportunity towards an efficient and safe drug delivery. Nevertheless, progresses in this field have been limited by an insufficient understanding of the potential cytotoxic effects of US related to the failure of the cellular repair and to the possible activation of inflammatory pathway. In this framework we studied the in vitro effects of very low-intensity US on a human keratinocyte cell line, which represents an ideal model system of skin protective barrier cells which are the first to be involved during medical US treatments. Bioeffects linked to US application at 1 MHz varying the exposure parameters were investigated by fluorescence microscopy and fluorescence activated cell sorting. Our results indicate that keratinocytes undergoing low US doses can uptake drug model molecules with size and efficiency which depend on exposure parameters. According to sub-cavitation SP models, we have identified the range of doses triggering transient membrane SP, actually with negligible biological damage. By increasing US doses we observed a reduced cells viability and an inflammatory gene overexpression enlightening novel healthy relevant strategies

Comparative assessment of reproductive traits across different habitats in the endangered Webb's hyacinth (Bellevalia webbiana Parl.)

To pursue a proper conservation of narrow endemic species, the knowledge of basic reproductive strategies is crucial to plan adequate conservation activities. One of the most evolutionarily relevant and threatened Italian endemic is the Webb’s hyacinth (Bellevalia webbiana Parl.). As the reproductive behaviour of this species and its connection with human impact are currently unknown, the aim of this study was to characterise the reproductive traits of the Webb’s hyacinth in contrasting habitats. All the 5 known richest populations across the species range were investigated. Their reproductive strategies were inferred by measuring inflorescence height, fruit set, seed set and P/O ratio. Reproductive features varied greatly amongst stands and also in relation to the degree of human disturbance. However, in all cases, seed sets showed low values. P/O values point towards full xenogamy and it is concluded that effective cross-pollination may be the main mode of sexual reproduction in Bellevalia webbiana. The reasons for the low reproductive performances may reside in pollen limitation, Allee effect and/or intrinsic reduced fertility of the species. Given this scenario, conservation efforts for Webb’s hyacinth should focus on maintaining large and relatively dense populations, to guarantee some chance of in situ survival