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41.
Giulia Bernardini Maurizio Comanducci Stefania Bambini Giovanni Renzone Andrea Scaloni Giovanna Morelli Mark Achtman Giulio Ratti Annalisa Santucci 《Proteomics. Clinical applications》2009,3(10):1251-1254
We previously described the first reference map for the proteome of one strain of serogroup A Neisseria meningitidis (MenA), a major cause of epidemic meningitis in humans. As a preliminary finding, in that work we noted that 2‐DE protein maps of closely related MenA isolates from different epidemics spreads could be easily compared to detect minor differences and that 2‐DE phenotypes attributable to the well‐known epidemiological marker tbpB agreed with the genoclouds model of MenA epidemiological variation during pandemic waves. We explored here the possibility that an extended comparative study of 2‐DE maps of isolates representative of the nine genoclouds described by Achtman and collaborators could be used to discriminate between strains otherwise undistinguishable. We showed the example of 14 proteins with different 2‐DE spot patterns in different genoclouds that could be considered as putative tracers for alike‐strains discrimination. We introduce the novel concept that comparative proteomics can be useful in identifying new epidemiological markers for N. meningitidis. 相似文献
42.
A new route for obtaining 1,4-cyclooctadiene by catalytic isomerization of 1,5-cyclooctadiene at low temperature in presence
of H2 in a three-phase reactor is presented. Wei, Prater and Silvestri methods are used for the kinetic studies. A comparison of
the activity-selectivity patterns of the Pd/pumice catalysts with Pd on silica and Pt and Pd–Pt on pumice catalysts is performed.
Although Pt catalysts are not active in the hydro-isomerization of 1,5-cyclooctadiene, the presence of small amount of Pt
in Pd/pumice catalysts increases the yield to 1,4-cyclooctadiene. Besides the catalyst characteristics, temperature and H2 pressure influence the production of 1,4-cyclooctadiene. A mechanism of the process is proposed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
43.
Giovanni Di Nicola Giuliano Giuliani Fabio Polonara Giulio Santori Roman Stryjek 《International Journal of Thermophysics》2010,31(10):1880-1887
A recently built experimental setup was employed for the estimation of the solid–liquid equilibria of alternative refrigerant systems. In this paper two binaries, i.e., carbon dioxide + trifluoromethane (CO2 + R23) and nitrous oxide + trifluoromethane (N2O + R23), were studied down to temperatures of 117 K. In order to check the reliability of the apparatus, the triple points of the pure fluids contained in the mixture were measured, revealing good consistency with the literature. The results obtained for the mixtures were interpreted by means of the Schröder equation. 相似文献
44.
Giulio Timelli Giordano Camicia Stefano Ferraro Roberto Molina 《Metals and Materials International》2014,20(4):677-686
The effects of grain refinement on the microstructure and mechanical properties of a secondary AlSi7-Cu3Mg gravity die cast cylinder head are reported. Metallographic and image analysis techniques have been used to quantitatively examine the macro- and microstructural changes occurring with the addition of grain-refining agent. The results indicate that the AlTi5B1 addition produces a fine and uniform grain structure throughout the casting; this effect is more pronounced in the slowly solidified regions. The initial contents of Ti and B, which are present as impurity elements in the supplied secondary alloy ingots, are not sufficient to produce effective grain refinement. Under the present casting conditions, the combined addition of AlTi5B1 and Sr does not produce any reciprocal interaction or effect on primary α-Al and eutectic solidification. Grain refinement improves the mechanical properties of the as-cast AlSi7Cu3Mg alloy and produces higher Weibull moduli, thus increasing the reliability of the casting. For automotive structural components, this could be considered an increase in safety. 相似文献
45.
Matteo Ageno Gabriella Bolzon Giulio Maier 《Structural and Multidisciplinary Optimization》2009,38(3):229-243
A model calibration technique is considered for the estimation of material parameters in free-standing thin foils. The experimental
apparatus is inspired by bursting strength testers for paper, textile fabrics and polymer coatings such as geo-membranes.
The procedure referred to herein consists of the following phases. A controlled fluid pressure is applied to the foil specimen
placed on an horizontal plane with a suitably shaped hole. The induced out-of-plane displacements are measured by a laser
profilometer. The material parameters are then inferred from these measurements through inverse analysis, by simulation of
the test and minimisation of a suitable norm which defines the discrepancy between measured and computed displacements. Potentialities
and limitations of the proposed method are assessed on the basis of computer-generated “pseudo-experimental” data, where modelling
errors are ruled out. The identifiability of some industrially meaningful material parameters is established. 相似文献
46.
We introduce a model of fluid which has four main features: it readily emerges by a general continuum mechanical framework; it is a generalization maintaining most of the physical features of incompressible Newtonian fluids; it can model adherence interactions with one-dimensional structures surrounded by the fluid; the associated initial boundary-value problem is well-posed on three-dimensional domains. 相似文献
47.
I. Dantone L. Fabbri E. Foschi C. Guandalini G. Laurenti I. Lax G. Levi L. Quadrani Ca. Sbarra Cr. Sbarra M. Villa A. Zoccoli M. Zuffa 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,630(1):384
The silicon photomultipliers (SiPM) are adopted in various physical applications, from medical physics to astrophysics, for their advantages in terms of cost and weight with respect to traditional photo detectors. Their low bias voltage supply (about 30 V), hardiness and resistance to magnetic field are ideal characteristics for space application. In the frame of INFN-Irst collaboration, some of them have been developed and produced at FBK (Trento-Italy), and have been characterized in the INFN laboratories of Bologna (DaSiPM2 collaboration).The SiPM can be used in conjunction with fibres and counters in high energy physics experiments. To exploit the SiPM time resolution, a fast amplifier has been studied. The SiPM gain depends critically on temperature and a thermal stabilization is also necessary. The use of a thermoelectric cooler module based on a Peltier cell has been investigated, and the results are shown. 相似文献
48.
Mariaelena Tagliabue Osvaldo Da PosAndrea Spoto Giulio Vidotto 《Accident; analysis and prevention》2013
Riding a moped, like many other everyday activities, is a complex behavior in which attention plays a crucial role. This study aims to investigate the role of attention in enhancing the skills required to ride a moped simulator. Two experiments were conducted with 207 and 60 students (14–15 years old), respectively, using a moped simulator to ride on 12 different tracks. The assignment was to ride safely and avoid hazards. In experiment 1, we divided the hazard scenes of the tracks on the basis of the fact that a shift in attention was required to escape the danger. We showed that during the riding training, when no attentional shift was required, the ability to avoid hazards was constantly higher. In experiment 2, participants were asked to cope with the same basic experimental setting but with an additional attentive task. The results showed that they performed in such a way that not only did the attentive task not impair their performance, but it also produced an improvement in the ability to shift attentional focus, preserving performance efficiency. On the basis of these data, it can be claimed that, primarily, attentional shift plays a prominent role in accounting for accident circumstances. Secondarily, it can be claimed that attentional training contributes to improved processing efficiency so as to prevent mishaps. 相似文献
49.
We examined two emission abatement systems of some vulcanization ovens, serving a unit producing small rubber-based parts for automotive application. Each emission control unit treats the gases exhausted by three to five ovens. A heat exchanger cools down the fumes to a temperature suitable for the correct operation of a couple of two-stage electrostatic precipitators in series. We performed quantitative analysis of concentrations and size distributions in these rubber fumes using aerosol technology instrumentation, namely optical particle spectrometers and electrical mobility particle sizers. The size of sampled particles was mainly between 100?nm and 1000?nm. We evaluated the performance of the exhaust fume abatement units, with focus on the electrostatic precipitator. Concerning batch ovens, the quantitative trend of the emissions follows the thermal cycle of the post-curing process. Time interval since the last maintenance operation causes a gradual reduction in the removal efficiency. The measured data demonstrate the reliability and the adequacy of aerosol instrumentation for the characterization of the emissions from rubber vulcanization ovens. The pair of electrostatic precipitators was shown to be effective in removing most of the particles detected in the fumes stream. The measurement protocol developed in this study allows assessing the influence of the maintenance schedule on the performance of the emission control units. New technologies for treating organic vapors can be evaluated in a reliable and effective way.Copyright © 2019 American Association for Aerosol Research 相似文献
50.
Giulio Giovannetti Francesca Frijia Simona Attanasio Luca Menichetti Valentina Hartwig Nicola Vanello Jan Henrik Ardenkjaer-Larsen Daniele De Marchi Vincenzo Positano Rolf Schulte Luigi Landini Massimo Lombardi Maria Filomena Santarelli 《Measurement》2013
Hyperpolarized 13C magnetic resonance spectroscopy in pig models enables cardiac metabolism assessment and provides a powerful tool for heart physiology studies, although the low molar concentration of derivate metabolites gives rise to technological limitations in terms of data quality. The design of dedicated coils capable of providing large field of view with high Signal-to-Noise Ratio (SNR) data is of fundamental importance. 相似文献