First Fifty Years of Chemoresistive Gas Sensors

The first fifty years of chemoresistive sensors for gas detection are here reviewed, focusing on the main scientific and technological innovations that have occurred in the field over the course of these years. A look at advances made in fundamental and applied research and leading to the development of actual high performance chemoresistive devices is presented. The approaches devoted to the synthesis of novel semiconducting materials with unprecedented nanostructure and gas-sensing properties have been also presented. Perspectives on new technologies and future applications of chemoresistive gas sensors have also been highlighted

Defective oxytocin function: a clue to understanding the cause of autism?

The autism spectrum disorders are a group of conditions with neurobehavioral impairment affecting approximately 0.6% of children. The clinical presentation is complex and the etiology is largely unknown, although a major role of genetic factors is widely accepted. A number of genetic studies led to the identification of genes and/or copy number variants whose alterations are associated with autism, but no specific factor has been found so far to be responsible for a substantial proportion of cases. Epigenetic modifications may also play a role, as demonstrated by the occurrence of autism in genetic conditions caused by mutations in imprinted genes or regions

Invalid proxies and volatility changes

When in proxy-SVARs the covariance matrix of VAR disturbances is subject to exogenous, permanent, nonrecurring breaks that generate target impulse response functions (IRFs) that change across volatility regimes, even strong, exogenous external instruments can result in inconsistent estimates of the dynamic causal effects of interest if the breaks are not properly accounted for. In such cases, it is essential to explicitly incorporate the shifts in unconditional volatility in order to point-identify the target structural shocks and possibly restore consistency. We demonstrate that, under a necessary and sufficient rank condition that leverages moments implied by changes in volatility, the target IRFs can be point-identified and consistently estimated. Importantly, standard asymptotic inference remains valid in this context despite (i) the covariance between the proxies and the instrumented structural shocks being local-to-zero, as in Staiger and Stock (1997), and (ii) the potential failure of instrument exogeneity. We introduce a novel identification strategy that appropriately combines external instruments with "informative" changes in volatility, thus obviating the need to assume proxy relevance and exogeneity in estimation. We illustrate the effectiveness of the suggested method by revisiting a fiscal proxy-SVAR previously estimated in the literature, complementing the fiscal instruments with information derived from the massive reduction in volatility observed in the transition from the Great Inflation to the Great Moderation regimes

Health-related quality of life in patients with Gilles de la Tourette syndrome at the transition between adolescence and adulthood

Gilles de la Tourette syndrome (GTS) is a neurodevelopmental condition characterised by tics and comorbid behavioural problems, affecting predominantly male patients. Tic severity typically fluctuates over time, with a consistent pattern showing improvement after adolescence in a considerable proportion of patients. Both tics and behavioural co-morbidities have been shown to have the potential to affect patients’ health-related quality of life (HR-QoL) in children and adults with persisting symptoms. In this study, we present the results of the first investigation of HR-QoL in patients with Gilles de la Tourette syndrome at the transition between adolescence and adulthood using a disease-specific HR-QoL measure, the Gilles de la Tourette Syndrome-Quality of Life-Children and Adolescents scale. Our results showed that patients with GTS and more severe co-morbid anxiety symptoms reported lower HR-QoL across all domains, highlighting the impact of anxiety on patient’s well-being at a critical stage of development. Routine screening for anxiety symptoms is recommended in all patients with GTS seen at transition clinics from paediatric to adult care, to implement effective behavioural and pharmacological interventions as appropriate

Errori di misura nellÂ’indagine sui bilanci delle famiglie italiane

This paper is aimed at evaluating the incidence of measurement error on the main variables collected in the Bank of ItalyÂ’s Survey of Household Income and Wealth (SHIW). The results are especially relevant to researchers using the data for economic analysis, since they need to take data quality into account. Moreover, a thorough knowledge of the problems affecting the survey gives indications for improvements in its design and implementation. Where time-invariant variables are concerned, measurement error is studied by assessing the degree of inconsistency of answers given by panel households in subsequent survey waves. In the case of quantities that have an actual variation in time, such as income or wealth, the Heise (1969) model is applied; if data from at least three waves are available, we can separate the true dynamics from the noise of measurement error, under assumptions that are fairly mild. The essay also touches upon the role of fieldwork conditions, interviewer and respondent features in the determination of data quality.reddito, ricchezza, metodi campionari

Three variants of three Stage Optimal Memetic Exploration for handling non-separable fitness landscapes

The file attached to this record is the authors final peer reviewed version. The publisher's final version can be found by following the DOI link.Three Stage Optimal Memetic Exploration (3SOME) is a recently proposed algorithmic framework which sequentially perturbs a single solution by means of three operators. Although 3SOME proved to be extremely successful at handling high-dimensional multi-modal landscapes, its application to non-separable fitness functions present some flaws. This paper proposes three possible variants of the original 3SOME algorithm aimed at improving its performance on non-separable problems. The first variant replaces one of the 3SOME operators, namely the middle distance exploration, with a rotation-invariant Differential Evolution (DE) mutation scheme, which is applied on three solutions sampled in a progressively shrinking search space. In the second proposed mechanism, a micro-population rotation-invariant DE is integrated within the algorithmic framework. The third approach employs the search logic (1+1)-Covariance Matrix Adaptation Evolution Strategy, aka (1+1)-CMA-ES. In the latter scheme, a Covariance Matrix adapts to the landscape during the optimization in order to determine the most promising search directions. Numerical results show that, at the cost of a higher complexity, the three approaches proposed are able to improve upon 3SOME performance for non-separable problems without an excessive performance deterioration in the other problems

Effects of eruption source parameter variation and meteorological dataset on tephra fallout hazard assessment: example from Vesuvius (Italy)

In this study, using the tephra dispersal model HAZMAP, we investigate the effect of using different meteorological datasets and eruption source parameters on tephra fallout hazard assessment for a sub-Plinian eruption of Vesuvius, which is considered as a reference case for hazard assessment analysis. We analyze the effect of using different meteorological data, from: i) radio-sounding carried out at the meteorological station of Brindisi (Italy) between 1962 and 1976 and between 1996 and 2012, and at Pratica di Mare (Rome, Italy) between 1995 and 2013; ii) meteorological models of the National Oceanic and Atmospheric Administration (NOAA), and of the European Centre for Medium-Range Weather Forecasts (ECMWF). Furthermore, we consider the effects of perturbing reference eruptive source parameters. In particular, we vary the total mass, the total grain-size distribution, the column height, and the effective atmospheric diffusion coefficient to evaluate how these parameters affect the hazard probability maps. Moreover, the effect of the seasonal variation of the wind field and the effect of the rain on the deposit loading are considered. Results show that the parameter that mostly affects hazard maps is, as expected, the total erupted mass; furthermore, keeping constant the erupted mass, the most important control on hazard is due to the particle terminal settling velocity distribution which is a function of the total grain-size distribution, particle density and shape. Within the considered range variations, the hazard depends less on the use of different meteorological datasets, column height and effective diffusion coefficient