experimental results of a wankel type expander fuelled by compressed air and saturated steam

Abstract The work presented in this paper deals with the experimental tests which were carried out on a prototype of a rotary volumetric expansion device based on the Wankel mechanism. This expansion device is addressed to small size power plants (in the range 5-50 kW) for distributed micro-generation using various sources of thermal energy, such as sun, biomass and waste heat. The prototype was built using an internal combustion Wankel engine, employing the shaft, the rotor, the bearings, while the statoric case was newly built on the design of the University of Pisa. Firstly, the tests were carried out with the compressed air produced by a compressor, then the prototype was fed with the saturated steam produced by a biomass boiler. In the first case, the exhaust back-pressure was the atmospheric one, in the second case vacuum conditions were employed thanks to a condenser. The inlet pressure was between 4 and 8 bar. The results showed the capability of the prototype to rotate regularly at 3000 rpm, and allowed the validation of numerical models presented in previous papers. Moreover, the expansion device showed the capability of developing the expected power

Synthesis and antibacterial effects of cobalt–cellulose magnetic nanocomposites

© The Royal Society of Chemistry. Green synthesis is employed to prepare cobalt/cellulose nanocomposites with cubic (α-cobalt) cobalt as a main component with antibacterial and magnetic properties. An in situ reduction of aqueous solutions of cobalt ions on a model cellulose substrate surface using hydrogen gas affords spherical, cellulose-stabilised cobalt nanoclusters with magnetic properties and an average diameter of 7 nm that are distributed evenly over the surface of the cellulose fibres. These cobalt/cellulose nanocomposites exhibit good antibacterial action against opportunistic pathogens both Gram-positive (S. aureus) and Gram-negative (E. coli, A. baumannii and P. aeruginosa), with zones of inhibition up to 15 mm, thereby encouraging the deployment of these advanced materials for the treatment of wastewater or within medical dressings. This method of preparation is compared with the analogous in situ reduction of cobalt ions on a cellulose surface using sodium borohydride as reducing agent

Ground-based NO2 measurements at the Italian Brewer stations: A pilot study with Global Ozone Monitoring Experiment (GOME)

Ground-based NO2 total column measurements have been collected since 1992 using Brewer spectrophotometry at Rome, an urban site, and Ispra (semirural). These are the only ground-based stations regularly monitoring NO2 in Italy. The methodology of measurement together with the procedure to control its quality is described. From the analysis of the time series it was found that the mean value of the NO2 column is 1.63 DU atRome and 1.60 DU atIspra. A firstat tempt to compare NO2 vertical column densities (VCD) from GOME with those derived from ground-based Brewer measurements, under different atmospheric conditions and measurement time lags is here presented. The results of this pilot study showed unsatisfactory agreement because different atmospheres are probed by GOME and Brewer instruments. The GOME space resolution resulted insufficient to fully characterize the Rome and Ispra highly localized polluted areas

Ground-based NO2 measurements at the Italian Brewer stations: A pilot study with Global Ozone Monitoring Experiment (GOME)

Ground-based NO2 total column measurements have been collected since 1992 using Brewer spectrophotometry at Rome, an urban site, and Ispra (semirural). These are the only ground-based stations regularly monitoring NO2 in Italy. The methodology of measurement together with the procedure to control its quality is described. From the analysis of the time series it was found that the mean value of the NO2 column is 1.63 DU atRome and 1.60 DU atIspra. A firstat tempt to compare NO2 vertical column densities (VCD) from GOME with those derived from ground-based Brewer measurements, under different atmospheric conditions and measurement time lags is here presented. The results of this pilot study showed unsatisfactory agreement because different atmospheres are probed by GOME and Brewer instruments. The GOME space resolution resulted insufficient to fully characterize the Rome and Ispra highly localized polluted areas

Reprint of: Internalising symptoms mediate the longitudinal association between childhood inflammation and psychotic-like experiences in adulthood

Psychotic-like experiences (PLEs) are part of a continuum of psychosis. Previous longitudinal studies highlighted a relationship between peripheral inflammation during childhood and onset of PLEs in adulthood. In this study, we tested if this association is mediated by internalising and externalising symptoms experienced during childhood and adolescence. To test this hypothesis, we used data from the Avon Longitudinal Study of Parents and Children (ALSPAC). We investigated a subsample of 4525 individuals from this cohort with data on interleukin 6 (IL-6) and C-reactive protein (CRP) in childhood (age 9 years). We measured PLEs at age 18 years, and we used latent growth curve modelling to estimate longitudinal trajectories of internalising and externalising symptoms from ages 9 to 16 years. The individual predicted values of the intercept (set at baseline, 9 years) and the slope (rate of annual change) were then used in the mediation analysis. There was evidence for full mediation by the intercept of internalising symptoms. Our findings suggest that inflammation during childhood may be relevant for the future onset of PLEs via its association with a high level of internalising symptoms. These findings, although obtained from a non-clinical population, provide an additional step in advancing knowledge on the relationship between inflammation and symptoms of the psychosis continuum

Commissioning of the MEG II tracker system

The MEG experiment at the Paul Scherrer Institut (PSI) represents the state of the art in the search for the charged Lepton Flavour Violating (cLFV) $\mu^+ \rightarrow e^+ \gamma$ decay. With the phase 1, MEG set the new world best upper limit on the \mbox{BR}(\mu^+ \rightarrow e^+ \gamma) < 4.2 \times 10^{-13} (90% C.L.). With the phase 2, MEG II, the experiment aims at reaching a sensitivity enhancement of about one order of magnitude compared to the previous MEG result. The new Cylindrical Drift CHamber (CDCH) is a key detector for MEG II. CDCH is a low-mass single volume detector with high granularity: 9 layers of 192 drift cells, few mm wide, defined by $\sim 12000$ wires in a stereo configuration for longitudinal hit localization. The filling gas mixture is Helium:Isobutane (90:10). The total radiation length is $1.5 \times 10^{-3}$ \mbox{X}_0, thus minimizing the Multiple Coulomb Scattering (MCS) contribution and allowing for a single-hit resolution $< 120$ $\mu$m and an angular and momentum resolutions of 6 mrad and 90 keV/c respectively. This article presents the CDCH commissioning activities at PSI after the wiring phase at INFN Lecce and the assembly phase at INFN Pisa. The endcaps preparation, HV tests and conditioning of the chamber are described, aiming at reaching the final stable working point. The integration into the MEG II experimental apparatus is described, in view of the first data taking with cosmic rays and $\mu^+$ beam during the 2018 and 2019 engineering runs. The first gas gain results are also shown. A full engineering run with all the upgraded detectors and the complete DAQ electronics is expected to start in 2020, followed by three years of physics data taking.Comment: 10 pages, 12 figures, 1 table, proceeding at INSTR'20 conference, accepted for publication in JINS

Salivary and gut microbiomes play a significant role in in vitro oral bioaccessibility, biotransformation, and intestinal absorption of arsenic from food

The release of a toxicant from a food matrix during the gastrointestinal digestion is a crucial determinant of the toxicant's oral bioavailability. We present a modified setup of the human simulator of the gut microbial ecosystem (SHIME), with four sequential gastrointestinal reactors (oral, stomach, small intestine, and colon), including the salivary and colonic microbiomes. Naturally arsenic-containing rice, mussels, and nori seaweed were digested in the presence of microorganisms and in vitro oral bioaccessibility, bioavailability, and metabolism of arsenic species were evaluated following analysis by using HPLC/mass spectrometry. When food matrices were digested with salivary bacteria, the soluble arsenic in the gastric digestion stage increased for mussel and nori samples, but no coincidence impact was found in the small intestinal and colonic digestion stages. However, the simulated small intestinal absorption of arsenic was increased in all food matrices (1.2-2.7 fold higher) following digestion with salivary microorganisms. No significant transformation of the arsenic species occurred except for the arsenosugars present in mussels and nori. In those samples, conversions between the oxo arsenosugars were observed in the small intestinal digestion stage whereupon the thioxo analogs became major metabolites. These results expand our knowledge on the likely metabolism and oral bioavailabiltiy of arsenic during human digestion, and provide valuable information for future risk assessments of dietary arsenic

The front end electronics for the drift chamber readout in MEG experiment upgrade

Front-end electronics plays an essential role in drift chambers for time resolution and, therefore, spatial resolution. The use of cluster timing techniques, by measuring the arriving times of all the individual ionization clusters after the first one, may enable to reach resolutions even below 100 μm in the measurement of the impact parameter. A high performance front-end electronics, characterized by low distortion, low noise and a wide bandwidth has been developed with the purpose to implement cluster timing techniques in the new drift chamber for the upgrade of the MEG experiment at Paul Sherrer Institut (CH)

Incidenza della sclerosi multipla in Toscana: uno studio basato su dati amministrativi

INTRODUZIONE L’Italia è un’area ad elevato rischio di sclerosi multipla (SM) con una prevalenza stimata di 75.000 casi e un’incidenza di 2.000 casi annui. Gli ultimi dati pubblicati sull’incidenza sono 5,5 casi/105 a Padova (2000-09), 6,6 a Genova (1998-2007) e 9,7 in Sardegna (2003-07). In Toscana è presente un registro regionale della SM ma, ad oggi, non è rappresentativo dell’intera popolazione. Una possibile alternativa per studiare l’epidemiologia è attraverso i dati amministrativi. Questi, infatti, coprono l’intera popolazione residente e vengono raccolti di routine in un modo standardizzato ai fini della gestione del servizio sanitario. Il nostro scopo è calcolare l’incidenza della SM in Toscana utilizzando dati amministrativi. METODI Per il calcolo dell’incidenza abbiamo creato il seguente algoritmo: ospedalizzazione in reparto per acuti e con diagnosi primaria di SM, esenzione attiva per SM, e prescrizione di farmaci specifici. I casi incidenti sono stati identificati come quei casi catturati dall’algoritmo non tracciati in precedenza nei flussi amministrativi, e la data della prima traccia è stata considerata quale data di diagnosi della SM. Da questa coorte di soggetti abbiamo selezionato i pazienti con un’età ≤ 55 anni, residenti in Toscana al momento della diagnosi e presenti in anagrafe da almeno 10 anni (o nati in Toscana se età <10). Abbiamo calcolato i tassi grezzi e standardizzati e gli intervalli di confidenza (IC) al 95% per gli anni 2011-2015. RISULTATI Abbiamo identificato, negli anni analizzati, 1.056 nuovi casi con un’incidenza che varia da 5,04/105 nel 2011 a 6,02 casi/105nel 2015 (Tab 1). Nelle donne l’incidenza è circa due volte più alta rispetto agli uomini con un range che va da 6,48 a 7,96/105 nelle donne, e da 3,49 a 3,93/105 negli uomini. CONCLUSIONI L’incidenza calcolata risulta elevata, soprattutto nelle donne, ma comunque in linea ai dati pubblicati in altre Regioni, al di là dei bias metodologici legati all’uso di dati amministrativi