11 research outputs found
Apparatus for simultaneous DLS-SANS investigations of dynamics and structure in soft matter
Dynamic Light Scattering (DLS) and Small-Angle Neutron Scattering (SANS) are
two key tools with which to probe the dynamic and static structure factor,
respectively, in soft matter. Usually DLS and SANS measurements are performed
separately, in different laboratories, on different samples and at different
times. However, this methodology has particular disadvantages for a large
variety of soft materials which exhibit high sensitivity to small changes in
fundamental parameters such as waiting times, concentration, pH, ionic
strength, etc. Here we report on a new portable DLS-SANS apparatus that allows
one to simultaneously measure both the microscopic dynamics (through DLS) and
the static structure (through SANS) on the same sample. The apparatus has been
constructed as a collaboration between two laboratories, each an expert in one
of the scattering methods, and was commissioned on the \textit{LOQ} and
\textit{ZOOM} SANS instruments at the ISIS Pulsed Neutron \& Muon Source, U.K
Thermoelasticity and ArUco marker-based model validation of polymer structure: application to the San Giorgio's bridge inspection robot
Experimental procedures are often involved in the numerical models validation. To define the behaviour of a structure, its underlying dynamics and stress distributions are generally investigated. In this research, a multi-instrumental and multi-spectral method is proposed in order to validate the numerical model of the Inspection Robot mounted on the new San Giorgio's Bridge on the Polcevera river. An infrared thermoelasticity-based approach is used to measure stress-concentration factors and, additionally, an innovative methodology is implemented to define the natural frequencies of the Robot Inspection structure, based on the detection of ArUco fiducial markers. Established impact hammer procedure is also performed for the validation of the results.</p
Acute Delta Hepatitis in Italy spanning three decades (1991â2019): Evidence for the effectiveness of the hepatitis B vaccination campaign
Updated incidence data of acute Delta virus hepatitis (HDV) are lacking worldwide. Our aim was to evaluate incidence of and risk factors for acute HDV in Italy after the introduction of the compulsory vaccination against hepatitis B virus (HBV) in 1991. Data were obtained from the National Surveillance System of acute viral hepatitis (SEIEVA). Independent predictors of HDV were assessed by logistic-regression analysis. The incidence of acute HDV per 1-million population declined from 3.2 cases in 1987 to 0.04 in 2019, parallel to that of acute HBV per 100,000 from 10.0 to 0.39 cases during the same period. The median age of cases increased from 27 years in the decade 1991-1999 to 44 years in the decade 2010-2019 (p < .001). Over the same period, the male/female ratio decreased from 3.8 to 2.1, the proportion of coinfections increased from 55% to 75% (p = .003) and that of HBsAg positive acute hepatitis tested for by IgM anti-HDV linearly decreased from 50.1% to 34.1% (p < .001). People born abroad accounted for 24.6% of cases in 2004-2010 and 32.1% in 2011-2019. In the period 2010-2019, risky sexual behaviour (O.R. 4.2; 95%CI: 1.4-12.8) was the sole independent predictor of acute HDV; conversely intravenous drug use was no longer associated (O.R. 1.25; 95%CI: 0.15-10.22) with this. In conclusion, HBV vaccination was an effective measure to control acute HDV. Intravenous drug use is no longer an efficient mode of HDV spread. Testing for IgM-anti HDV is a grey area requiring alert. Acute HDV in foreigners should be monitored in the years to come
Scalable six bar linkage mechanism for re-orienting and aligning objects: Design methodology
This paper summarizes the work done in the context of an industrial research project in collaboration between the Italian Institute of Technology and the company Fameccanica Data Spa. This paper introduces the design of a six bar linkage mechanism, actuated by a single motor, for re-orienting and aligning objects. The main application consists of grasping empty bottles lying flat on an input conveyor, rotating, aligning and placing them in upright position on another conveyor. The breakthrough aspect of the general and scalable design introduced lays in a system of kinematic equations whose solutions correspond to the linkage lengths. Such lengths define a six-bar-linkage able to re-orient and align vertically a generic object. Finally, this paper presents the mechanism prototype created for such industrial application for performing tests in an operational environment at high speed
Antibiotic resistance in wastewater treatment plants: tackling the black box
Wastewater is among the most important reservoirs of antibiotic resistance in urban environments. The abundance of carbon sources and other nutrients, a variety of possible electron acceptors such as oxygen or nitrate, the presence of particles onto which bacteria can adsorb, or a fairly stable pH and temperature are examples of conditions favouring the remarkable diversity of microorganisms in this peculiar habitat. The wastewater microbiome brings together bacteria of environmental, human and animal origins, many harbouring antibiotic resistance genes (ARGs). Although numerous factors contribute, mostly in a complex interplay, for shaping this microbiome, the effect of specific potential selective pressures such as antimicrobial residues or metals, is supposedly determinant to dictate the fate of antibiotic resistant bacteria (ARB) and ARGs during wastewater treatment. This paper aims to enrich the discussion on the ecology of ARB&ARGs in urban wastewater treatment plants (UWTPs), intending to serve as a guide for wastewater engineers or other professionals, who may be interested in studying or optimizing the wastewater treatment for the removal of ARB&ARGs. Fitting this aim, the paper overviews and discusses: i) aspects of the complexity of the wastewater system and/or treatment that may affect the fate of ARB&ARGs; ii) methods that can be used to explore the resistome, meaning the whole ARB&ARGs, in wastewater habitats; and iii) some frequently asked questions for which are proposed addressing modes. The paper aims at contributing to explore how ARB&ARGs behave in UWTPs having in mind that each plant is a unique system that will probably need a specific procedure to maximize ARB&ARGs removal.info:eu-repo/semantics/publishedVersio
Human platelet lysateâderived extracellular vesicles enhance angiogenesis through miRâ126
Extracellular vesicles (EVs) are key biological mediators of several physiological functions within the cell microenvironment. Platelets are the most abundant source of EVs in the blood. Similarly, platelet lysate (PL), the best platelet derivative and angiogenic performer for regenerative purposes, is enriched of EVs, but their role is still too poorly discovered to be suitably exploited. Here, we explored the contribution of the EVs in PL, by investigating the angiogenic features extrapolated from that possessed by PL.
Methods: We tested angiogenic ability and molecular cargo in 3D bioprinted models and by RNA sequencing analysis of PL-derived EVs.
Results: A subset of small vesicles is highly represented in PL. The EVs do not retain aggregation ability, preserving a low redox state in human umbilical vein endothelial cells (HUVECs) and increasing the angiogenic tubularly-like structures in 3D endothelial bioprinted constructs. EVs resembled the miRNome profile of PL, mainly enriched with small RNAs and a high amount of miR-126, the most abundant angiogenic miRNA in platelets. The transfer of miR-126 by EVs in HUVEC after the in vitro inhibition of the endogenous form, restored angiogenesis, without involving VEGF as a downstream target in this system.
Conclusion: PL is a biological source of available EVs with angiogenic effects involving a miRNAs-based cargo. These properties can be exploited for targeted molecular/biological manipulation of PL, by potentially developing a product exclusively manufactured of EVs
Dieci domande sulla riforma costituzionale
Analisi del procedimento di revisione della parte seconda della Costituzione e della natura del referendum previsto dall'art. 138 Cost
Dieci domande sulla riforma costituzionale
Discussione di alcuni nodi critici della riforma costituzionale della XVII legislatura, entro un Forum tra costituzionalisti invitati dalla redazione, muovendo da una serie di domande comuni proposte dalla rivista (gli invitati potevano scegliere liberamente se rispondere, in breve, a ciascuna di esse oppure dilungarsi di piĂč su un numero ristretto di questioni)