Dark Field Differential Dynamic Microscopy enables the accurate characterization of the roto-translational dynamics of bacteria and colloidal clusters

Micro- and nanoscale objects with anisotropic shape are key components of a variety of biological systems and inert complex materials, and represent fundamental building blocks of novel self-assembly strategies. The time scale of their thermal motion is set by their translational and rotational diffusion coefficients, whose measurement may become difficult for relatively large particles with small optical contrast. Here we show that Dark Field Differential Dynamic Microscopy is the ideal tool for probing the roto-translational Brownian motion of shape anisotropic particles. We demonstrate our approach by successful application to aqueous dispersions of non-motile bacteria and of colloidal aggregates of spherical particles

Phantom Membrane Microfluidic Cross-Flow Filtration Device for the Direct Optical Detection of Water Pollutants

The diffusion of autonomous sensing platforms capable of a remote large-scale surveillance of environmental water basins is currently limited by the cost and complexity of standard analytical methods. In order to create a new generation of water analysis systems suitable for continuous monitoring of a large number of sites, novel technical solutions for fluid handling and detection are needed. Here we present a microfluidic device hosting a perfluorinated microporous membrane with refractive index similar to that of water, which enables the combination of filtration and label-free sensing of adsorbing substances, mainly pollutants, in environmental water samples. The cross-flow design of the microfluidic device avoids the clogging of the membrane due to particulate, whereas molecules with some hydrophobic moiety contained in the crossing flow are partially retained and their adhesion on the inner surface of the membrane yields an increase of light scattering intensity, which can be easily measured using a simple instrument based on Light Emitting Diode illumination. By cycling sample water and pure water as a reference, we demonstrate the detection of 0.5 microM of a model cationic surfactant and regeneration of the sensing surface. The optical response of the membrane sensor was characterized using a simple theoretical model that enables to quantify the concentration of target molecules from the amplitude and kinetics of the measured binding curves. The device was tested with real water samples containing large amount of environmental particles, without showing clogging of the membrane, and enabling nonspecific quantification of adsorbing substances in a few minutes.This project has received funding from the European Union’s Seventh Framework Programme (FP7) for Research, Technological Development and Demonstration through the NAPES project(grant agreement no. 604241). FBL acknowledges the Ramón y CajalProgramme (Ministerio de Economía y Competitividad), Spain. FBL personally acknowledges to Elkartek (KK-2015/00088) Grant from the Gobierno Vasco and funding support from Gobierno de España, Ministerio de Economia y Competitividad, with Grant No. BIO2016-80417-P and to Marian M. De Pancorbo for letting him to use her laboratory facilities at UPV/EHU. PSA was generously provided byAdhesive Research, Ireland. We thank Aurora Giavazzi for helping in the collection of river water samples

X-ray Imaging Investigation on the Gilding Technique of an Ancient Egyptian Taweret Wooden Statuette

Diagnostic physical methods are increasingly applied to Cultural Heritage both for scientific investigations and conservation purposes. In particular, the X-ray imaging techniques of computed tomography (CT) and digital radiography (DR) are non-destructive investigation methods to study an object, being able to give information on its inner structure. In this paper, we present the results of the X-ray imaging study on an ancient Egyptian statuette (Late Period 722–30 BCE) belonging to the collection of Museo Egizio in Torino and representing an Egyptian goddess called Taweret, carved on wood and gilded with some colored details. Since few specific studies have been focused on materials and techniques used in Ancient Egypt for gilding, a detailed investigation was started in order to verify the technical features of the decoration in this sculpture. Specifically, DR and CT analyses have been performed at the Centro Conservazione e Restauro “La Venaria Reale” (CCR), with a new high resolution flat-panel detector, that allowed us to perform tomographic analysis reaching a final resolution better than the one achievable with the previous apparatus operating in the CCR

An Ancient Egyptian Multilayered Polychrome Wooden Sculpture Belonging to the Museo Egizio of Torino: Characterization of Painting Materials and Design of Cleaning Processes by Means of Highly Retentive Hydrogels

This contribution focuses on the conservation of an Egyptian wooden sculpture (Inventory Number Cat. 745) belonging to the Museo Egizio of Torino in northwest Italy. A preliminary and interdisciplinary study of constituent painting materials and their layering is here provided. It was conducted by means of a multi-technique approach starting from non-invasive multispectral analysis on the whole object, and subsequently, on selected micro-samples. In particular, visible fluorescence induced by ultraviolet radiation (UVF), infrared reflectography (IRR) and visible--induced infrared luminescence were used on the whole object. The micro-samples were analysed by means of an optical microscope with visible and UV light sources, a scanning electron microscope (SEM) with an energy-dispersive X-ray spectrometer (EDX), Fourier transform infrared (FT-IR) spectrometer, pyrolysis-gas chromatography/mass spectrometer (Py-GC/MS) and micro-particle induced X-ray emission (PIXE). The characterization of the painting materials allowed the detection of Egyptian blue and Egyptian green, and also confirmed the pertinence of the top brown layer to the original materials, which is a key point to design a suitable surface treatment. In fact, due to the water sensitiveness of the original materials, only few options were available to perform cleaning operations on this artwork. To setup the cleaning procedure, we performed several preliminary tests on mockups using dry cleaning materials, commonly used to treat reactive surfaces, and innovative highly water retentive hydrogels, which can potentially limit the mechanical action on the original surface while proving excellent cleaning results. Overall, this study has proved fundamental to increase our knowledge on ancient Egyptian artistic techniques and contribute to hypothesize the possible provenance of the artefact. It also demonstrated that polyvinyl alcohol-based retentive gels allow for the safe and efficient cleaning of extremely water sensitive painted surfaces, as those typical of ancient Egyptian artefacts

B-site vacancy induced Raman scattering in BaTiO3-based ferroelectric ceramics

Defects, in particular vacancies, play a crucial role in substituted perovskite systems, influencing the structural features that underpin ferroelectricity. B-site vacancies introduce cation disorder in the perovskite lattice and are in fact one of the main driving forces for relaxor behaviour in barium titanate (BaTiO3, BT) based ferroelectrics. In this work, material systems are carefully selected to qualitatively study the change in B-site vacancy concentration for heterovalent substituted BT-based ferroelectric polycrystals. Raman spectroscopy was used to investigate those systems, and B-site vacancy specific Raman modes were identified unambiguously by comparison with charge-compensated BT, where B-site vacancies are absent. This study validates the hypothesis that vacancies induce Raman scattering because of symmetry breaking in the BT lattice, establishing this method as a vital tool to study substitutional defects in ceramic materials

Intensive intervention for children and adolescents with autism in a community setting in Italy: a single-group longitudinal study

<p>Abstract</p> <p>Background</p> <p>Previous studies have shown favourable results with intensive behavioural treatment for children with autism: evidence has emerged that treatment can be successfully implemented in a community setting and in adolescent participants. The aim of this study was to describe the 2-year adaptive functioning outcome of children and adolescents with autism treated intensively within the context of special autism centres, as well as to evaluate family satisfaction with the activity of the centres.</p> <p>Methods</p> <p>Sixty participants with autism (20 females and 40 males, aged between 4 and 18 years) attending the semi-residential rehabilitation centres for autism located in the Abruzzo region (Central Italy) were followed up and their adaptive functioning was evaluated both at baseline and after one and two years using the Vineland Adaptive Behaviour Scales (VABS). Parents' satisfaction with the service was evaluated using the Orbetello Satisfaction Scale for Children and Adolescent Mental Health.</p> <p>Results</p> <p>The increase in VABS scores was significant on several domains in the different gender and age categories. It is worth noting that male children had improved a great deal (roughly, an effect size >0.20) in the domains of communication, daily living and motor skills (effect sizes 0.34, 0.45 and 0.27 respectively) whereas in male adolescents, a notable increase in VABS scores was recorded in the domain of socialization only (effect size 0.23). On the other hand, adaptive behaviour in female children increased in the domains of socialization and motor skills (effect sizes 0.27 and 0.42 respectively) whereas in female adolescents, good results were achieved in the domains of daily living, socialization and motor skills (effect sizes 0.22, 0.26 and 0.20 respectively).</p> <p>The level of satisfaction of users of the service over time was found to be substantial, even when they had recently started the program.</p> <p>Conclusions</p> <p>Our results support the implementation of special autism treatment community centres, based on a parent co-directed rehabilitative, intensive and early intervention. Further experimental research designed to document the effectiveness of services provided to children and adolescents with autism in the community is recommended.</p

Monte Carlo simulation of nematic liquid crystal in porous media : The topological constraint and surface anchoring effect(Knots and soft-matter physics: Topology of polymers and related topics in physics, mathematics and biology)

この論文は国立情報学研究所の電子図書館事業により電子化されました。多孔質に閉じ込められた系や不純物を含む凝縮系では、純粋な系に比べて様々な相転移現象が抑制されることが知られている。液晶における等方-ネマティック転移においても、多孔質中では不連続な一時転移を起こさなくなることが分かっている。しかしながら、液晶相は弾性的であり空間束縛を受けることにより弾性エネルギーが増大し配向欠陥が形成されるため、一般的な議論が用いることができない。例えば、この系では、外場によって平均的な配向方向を制御することができ、外場を除いた後もそれが保持されることが報告されている。これまで、不純物という形で閉じ込め効果を扱った研究した例はいくつかあったが、多孔質の構造そのものに注目したものはなく、どのように配向欠陥が束縛を受けるかなど明らかになっていない点も多く残っている。我々は様々な構造を持つ多孔質を用意し、それと配向欠陥のトポロジカルな構造との関係に着目し、メモリー効果を中心にそめ振舞いを調べた。相分離モデルを用いて双連結構造を用意し、その片方の相にLebwohl-Lasherポテンシャルで相互作用するスピンを導入し、モンテカルロシミュレーションを行った。また、図1は、双連結構造とその中に封入したネマティック液晶の配向欠陥なを図示したものである。十分にアニールしても、液晶相の配向欠陥は消失せず残ったままであった。この配向欠陥は一意に決まるものではなく、様々な配置状態を取りうるが、それらが熱的に状態遷移することはない。大きな外場を与えると、異なる欠陥構造を持つ局所安定状態に遷移するが、その後、外場を消しても配向欠陥のトポロジーは保持されるため、一時的に印加した外場の情報を「記憶」できることが分かった。また、キュービック相など秩序度の高い多孔質を用いることで、メモリー効果の効率が高くなることも示された

Method for the Measure of Molecular Interactions by Laser Light Scattering (LLS)

Procedure for the quantitative determination of interactions of ligands with receptors adsorbed on the surface of particles, by means of direct measure of the scattering of light by Laser Light Scattering (LLS), with the usage of submicrometric polymeric particles with diameter between 5 and 200 nm

Metodo di misurazione di interazioni molecolari mediante rilevazione di luce riflessa da superfici

Si descrive un procedimento per la determinazione quantitativa di interazioni di ligandi con recettori adsorbiti o immobilizzati sulla superficie di un materiale solido funzionalizzabile, trasparente e a basso indice di rifrazione, per mezzo di misurazione diretta della riflessione di luce