479 research outputs found
Iterative complex network approach for chemical gas sensor array characterisation
Gas sensor arrays, also known as e-noses, are used in several heterogeneous fields, ranging from environmental monitoring to food quality control. Often, these measurement systems operate within dynamic environments and are subject to conditions which may dramatically vary over time. Furthermore, the response of an e-nose is influenced by several parameters, whose interactions may be complex and highly non-linear. Therefore, in this study, the authors propose a complex network approach to model the overall interaction pattern of e-noses. They show that this approach can significantly improve the understanding of the overall behaviour of e-noses, and can be used as a basis to optimise the design of these measurement systems
Complex Network Modelling of Origin–Destination Commuting Flows for the COVID-19 Epidemic Spread Analysis in Italian Lombardy Region
Currently the whole world is affected by the COVID-19 disease. Italy was the first country to be seriously affected in Europe, where the first COVID-19 outbreak was localized in the Lombardy region. The further spreading of the cases led to the lockdown of the most affected regions in northern Italy and then the entire country. In this work we investigated an epidemic spread scenario in the Lombardy region by using the origin–destination matrix with information about the commuting flows among 1450 urban areas within the region. We performed a large-scale simulation-based modeling of the epidemic spread over the networks related to three main motivations, i.e., work, study and occasional transfers to quantify the potential contribution of each category of travellers to the spread of the epidemic process. Our findings outline that the three networks are characterised by different weight dynamic growth rates and that the network "work" has a critical role in the diffusion phenomenon showing the greatest contribution to the epidemic spread
An Artificial Miniaturized Peroxidase for Signal Amplification in Lateral Flow Immunoassays
Signal amplification strategies are widely used for improving the sensitivity of lateral flow immunoassays (LFiAs). Herein, the artificial miniaturized peroxidase Fe(III)-MimochromeVI*a (FeMC6*a), immobilized on gold nanoparticles (AuNPs), is used as a strategy to obtain catalytic signal amplification in sandwich immunoassays on lateral flow strips. The assay scheme uses AuNPs decorated with the mini-peroxidase FeMC6*a and anti-human-IgG as a detection antibody (dAb), for the detection of human-IgG, as a model analyte. Recognition of the analyte by the capture and detection antibodies is first evidenced by the appearance of a red color in the test line (TL), due to the accumulation of AuNPs. Subsequent addition of 3,3',5,5'-tetramethylbenzidine (TMB) induces an increase of the test line color, due to the TMB being converted into an insoluble colored product, catalyzed by FeMC6*a. This work shows that FeMC6*a acts as an efficient catalyst in paper, increasing the sensitivity of an LFiA up to four times with respect to a conventional LFiA. Furthermore, FeMC6*a achieves lower limits of detection that are found in control experiments where it is replaced with horseradish peroxidase (HRP), its natural counterpart. This study represents a significant proof-of-concept for the development of more sensitive LFiAs, for different analytes, based on properly designed artificial metalloenzymes
Long Term Wind Turbine Performance Analysis Through SCADA Data: A Case Study
Performance monitoring of horizontal-axis wind turbines is a complex task because they operate under nonstationary conditions. Furthermore, in real-world applications, there can be data quality issues because the free stream wind speed is reconstructed through a nacelle transfer function from cup anemometers measurements collected behind the rotor span. Given these matters of fact, one of the objectives of the present work is applying an innovative method for correcting the nacelle wind speed measurements, which is based on the manufacturer power curve and statistical considerations. Three operating wind turbines, having 2 MW of rated power and owned by the ENGIE Italia company, are contemplated as test cases. Operation data spanning ten years (2011–2020) are studied: actually, this work aims as well at contributing to the methods for estimating the performance decline with age of wind turbines, basing on long term SCADA data analysis. The raw and corrected wind speed measurements are fed as input to a Support Vector Regression for the power curve: by selecting appropriately the training and validation data sets, it is possible to estimate the average yearly rate of performance decline. Using the corrected wind speed, the estimate obtained in this study is compatible with the most recent findings in the literature, which indicate a -0.17% decline per year
Diagnosis and Treatment of Obstructive Hypertrophic Cardiomyopathy
Left ventricular outflow obstruction (LVOTO) and diastolic dysfunction are the main pathophysiological characteristics of hypertrophic cardiomyopathy (HCM)LVOTO, may be identified in more than half of HCM patients and represents an important determinant of symptoms and a predictor of worse prognosis. This review aims to clarify the LVOTO mechanism in, diagnosis of, and therapeutic strategies for patients with obstructive HCM
Avidities of human monoclonal antibodies derived from an adult immunized with pneumococcal polysaccharide vaccine
Plant based vaccines provide an instructive opportunity for immunologists. We have developed a plantbasedoral vaccine against verocytotoxin–producing E. coli (VTEC) in piglets (Rossi et. al 2014). Weengineered two independent lines of Nicotiana tabacum plants for the seed-specific expression of VTECantigens, represented by the major subunit FedA of the F18 adhesive fimbriae and the B-subunit of VT2etoxin respectively (Rossi et. al. 2013). Edible vaccines in particular are of interest as they are able tostimulate the mucosal immune system to produce secretory IgA (S-IgA) at mucosal surfaces and,potentially IgG in the blood. The quality of the antibodies, such as avidity, should be considered inevaluating the efficacy of these vaccines. To develop this area, we determined avidity (strength ofantibody-antigen binding) of IgG to the capsule of another mucosal pathogen, Streptococcuspneumoniae. Using pneumococcal capsule-specific IgG human monoclonal antibodies (hMAb) clonedfrom single cells of a subject immunized with pneumococcal vaccine, we defined serotypes specificityand the avidity of these antibodies with ammonium thiocyanate (0, 4M, 2M, 1M 0.5M 0.025M)dissociation. IgG with lower avidity to the capsule are dissociated at lower NH4SCN levels, whereas IgGwith higher affinity require higher levels. We identified a range of avidities for 11 hMAB’s (range X-YMNH4SCN). We will evaluate the avidity of antibodies after immunization with edible vaccines againstVTEC strain in piglets about which little in known, but as demonstrated in Granoff et al. the high-avidityantibodies are required in generating a more effective vaccine
THE MUSCLE SHORTENING MANOEUVRE: APPLICABILITY AND PRELIMINARY EVALUATION IN CHILDREN WITH HEMIPLEGIC CEREBRAL PALSY: A RETROSPECTIVE ANALYSIS
Enzymatic and Bioinspired Systems for Hydrogen Production
The extraordinary potential of hydrogen as a clean and sustainable fuel has sparked the interest of the scientific community to find environmentally friendly methods for its production. Biological catalysts are the most attractive solution, as they usually operate under mild conditions and do not produce carbon-containing byproducts. Hydrogenases promote reversible proton reduction to hydrogen in a variety of anoxic bacteria and algae, displaying unparallel catalytic performances. Attempts to use these sophisticated enzymes in scalable hydrogen production have been hampered by limitations associated with their production and stability. Inspired by nature, significant efforts have been made in the development of artificial systems able to promote the hydrogen evolution reaction, via either electrochemical or light-driven catalysis. Starting from small-molecule coordination compounds, peptide- and protein-based architectures have been constructed around the catalytic center with the aim of reproducing hydrogenase function into robust, efficient, and cost-effective catalysts. In this review, we first provide an overview of the structural and functional properties of hydrogenases, along with their integration in devices for hydrogen and energy production. Then, we describe the most recent advances in the development of homogeneous hydrogen evolution catalysts envisioned to mimic hydrogenases
Avidities of human monoclonal antibodies derived from an adult immunized with pneumococcal polysaccharide vaccine
Plant based vaccines provide an instructive opportunity for immunologists. We have developed a plantbasedoral vaccine against verocytotoxin–producing E. coli (VTEC) in piglets (Rossi et. al 2014). Weengineered two independent lines of Nicotiana tabacum plants for the seed-specific expression of VTECantigens, represented by the major subunit FedA of the F18 adhesive fimbriae and the B-subunit of VT2etoxin respectively (Rossi et. al. 2013). Edible vaccines in particular are of interest as they are able tostimulate the mucosal immune system to produce secretory IgA (S-IgA) at mucosal surfaces and,potentially IgG in the blood. The quality of the antibodies, such as avidity, should be considered inevaluating the efficacy of these vaccines. To develop this area, we determined avidity (strength ofantibody-antigen binding) of IgG to the capsule of another mucosal pathogen, Streptococcuspneumoniae. Using pneumococcal capsule-specific IgG human monoclonal antibodies (hMAb) clonedfrom single cells of a subject immunized with pneumococcal vaccine, we defined serotypes specificityand the avidity of these antibodies with ammonium thiocyanate (0, 4M, 2M, 1M 0.5M 0.025M)dissociation. IgG with lower avidity to the capsule are dissociated at lower NH4SCN levels, whereas IgGwith higher affinity require higher levels. We identified a range of avidities for 11 hMAB’s (range X-YMNH4SCN). We will evaluate the avidity of antibodies after immunization with edible vaccines againstVTEC strain in piglets about which little in known, but as demonstrated in Granoff et al. the high-avidityantibodies are required in generating a more effective vaccine
Avidities of human monoclonal antibodies derived from an adult immunized with pneumococcal polysaccharide vaccine
Plant based vaccines provide an instructive opportunity for immunologists. We have developed a plantbasedoral vaccine against verocytotoxin–producing E. coli (VTEC) in piglets (Rossi et. al 2014). Weengineered two independent lines of Nicotiana tabacum plants for the seed-specific expression of VTECantigens, represented by the major subunit FedA of the F18 adhesive fimbriae and the B-subunit of VT2etoxin respectively (Rossi et. al. 2013). Edible vaccines in particular are of interest as they are able tostimulate the mucosal immune system to produce secretory IgA (S-IgA) at mucosal surfaces and,potentially IgG in the blood. The quality of the antibodies, such as avidity, should be considered inevaluating the efficacy of these vaccines. To develop this area, we determined avidity (strength ofantibody-antigen binding) of IgG to the capsule of another mucosal pathogen, Streptococcuspneumoniae. Using pneumococcal capsule-specific IgG human monoclonal antibodies (hMAb) clonedfrom single cells of a subject immunized with pneumococcal vaccine, we defined serotypes specificityand the avidity of these antibodies with ammonium thiocyanate (0, 4M, 2M, 1M 0.5M 0.025M)dissociation. IgG with lower avidity to the capsule are dissociated at lower NH4SCN levels, whereas IgGwith higher affinity require higher levels. We identified a range of avidities for 11 hMAB’s (range X-YMNH4SCN). We will evaluate the avidity of antibodies after immunization with edible vaccines againstVTEC strain in piglets about which little in known, but as demonstrated in Granoff et al. the high-avidityantibodies are required in generating a more effective vaccine
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