Single-electron counting spectroscopy: simulation study of porphyrin in a molecular junction

Electron counting of a single porphyrin molecule between two electrodes shows a crossover from sub- to super-Poissonian statistics as the bias voltage is scanned. This is attributed to the simultaneous activation of states with electron transfer rates spanning several orders of magnitude. Time-series analysis of consecutive single-electron transfer events reveals fast and slow transport channels, which are not resolved by the average current alone.     

Anomalous Voltage Noise at the Superconducting Transition of Tin Films

We report voltage noise studies in the superconducting transition of thin Tin (Sn) films. Voltage noises are measured as a function of temperature and ac current. The noise spectral power S ^1/2 strongly depends on the temperature and current, with the peak temperature in S ^1/2 shifted down from that of dR/dT. Comparison with the dc noise measurement shows the S ^1/2 is much larger with ac current than dc. I–V characteristics and voltage noises are measured simultaneously to reveal the nature of the excess noises. The noise dependence on voltage strongly suggests the nature of vortex shot noise with a characteristic dependence for small V and reduction of S ^1/2 due to strong correlation of vortices at large V.      

HRMAS-NMR spectroscopy and multivariate analysis meat characterisation

(1)H-high resolution magic angle spinning-nuclear magnetic resonance spectroscopy was employed to gain the metabolic profile of longissimus dorsi and semitendinosus muscles of four different breeds: Chianina, Holstein Friesian, Maremmana and Buffalo. Principal component analysis, partial least squares projection to latent structure - discriminant analysis and orthogonal partial least squares projection to latent structure - discriminant analysis were used to build models capable of discriminating the muscle type according to the breed. Data analysis led to an excellent classification for Buffalo and Chianina, while for Holstein Friesian the separation was lower. In the case of Maremmana the use of intelligent bucketing was necessary due to some resonances shifting allowed improvement of the discrimination ability. Finally, by using the Variable Importance in Projection values the metabolites relevant for the classification were identified.     

Measurement of current-induced local heating in a single molecule junction

We have studied the current-induced local heating effects in single molecules covalently bound to two electrodes by measuring the force required to break the molecule-electrode bonds under various conditions. The breakdown process is thermally activated, which is used to extract the effective temperature of the molecular junction as a function of applied bias voltage. We have also performed first-principles calculations of both local heating and current-induced force effects, and the results are in good agreement with the experimental findings.     

R&;D for Quality Improvement and Network Externalities

We investigate the bearings of network externalities on product quality improvements requiring costly R&D investments. The model considers the dynamic behaviour of a monopolist alternatively maximising profits or social welfare. On the one hand, we confirm much of the acquired wisdom from the static literature on the same topic, about the arising of quality undersupply at the private optimum. On the other, we show that the monopoly optimum requires specific viability conditions, while the social optimum is always viable. We also show that the presence of network externalities affects the optimal investment behaviour of the profit-seeking firm but not that of a benevolent planner, who serves all consumers from the outset.     

Adaptive relay-based control of household freezers with on–off actuators

This paper describes an adaptive scheme for temperature control in household freezers with low-end sensing and actuation equipment, like on–off compressors and dampers. The scheme is based on an auxiliary filter introduced in the relay loop to alter and improve the characteristics of the induced oscillation. The filter is tuned adaptively to cope with system variability and uncertainty. Some tests on detailed simulation models of a commercial appliance are reported to validate the approach and show its effectiveness with respect to both food preservation and energy consumption requirements.     

Original article: Apparent thermal diffusivity estimation for the heat transfer modelling of pork loin under air/steam cooking treatments

Apparent thermal diffusivity linear functions vs. product temperature were estimated for pork cooked under two different treatments (forced convection, FC and forced convection/steam combined, FC/S) at 100, 110, 120 and 140 °C by means of experimental time–temperature data and a developed finite‐difference algorithm. Slope and intercept of each function were employed to calculate apparent thermal diffusivity at 40, 55 and 70 °C. Generally, FC/S treatments gave significantly higher apparent thermal diffusivities in comparison with FC conditions. Apparent thermal diffusivities were used to develop a model for cooking time and final core temperature prediction on the basis of oven setting. The model was validated by means of additional cooking tests performed at different temperatures of those employed for model development. Root mean square error values lower than 3.8 °C were obtained comparing predicted and experimental temperature profiles. Percentage errors lower than 3.1% and 3.5% were, respectively, obtained for cooking times and final core temperatures.     

Evidence for a role of the membrane-proximal region of herpes simplex virus type 1 glycoprotein H in membrane fusion and virus inhibition

We have identified a putative membrane-interacting domain preceding the transmembrane domain of the Herpes simplex virus type 1 (HSV-1) glycoprotein H (gH). Peptides derived from this region interact strongly with membranes and show a high tendency to partition at the interface. This region is predicted to bind at the membrane interface by adopting an alpha helical structure. Peptides representing either the HSV-1 gH pretransmembrane region or a scrambled control with a different hydrophobic profile at the point of interface have been studied. The peptides derived from this domain of gH induce the fusion of liposomal membranes, adopt helical conformations in membrane mimetic environments and are able to inhibit HSV-1 infectivity. The pretransmembrane region appears to be a common feature in viral fusion proteins of several virus families, and such a feature might be related to their fusogenic function. The identification of membrane-interacting regions capable of modifying the biophysical properties of phospholipid membranes lends weight to the view that such domains might function directly in the fusion process and could facilitate the future development of HSV-1 entry inhibitors.     

Coating of glass and polycarbonate with aqueous two‐component polyurethane resin

Hard polyurethane coatings combine several features as high flexibility and toughness, good chemical resistance, improved clarity, and spontaneous air‐drying. However, the coating design (thicknesses, interface pretreatments, substrate features, etc.) is often troublesome. In this respect, the present investigation deals with the application of high‐clarity polyurethane coatings on transparent glass and polycarbonates. In particular, the role of the coating thicknesses and, above all, of the different compliance of the substrates was investigated. Progressive mode scratch and dry sliding linear reciprocating tribological tests were carried out and scanning electron microscopy images were captured to analyze the deformation response of the polyurethane coatings. The experimental findings allow to better interpret the way to ruptures of the investigated coating systems and the mechanisms involved. Accordingly, new strategies to prevent them could be elicited. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014 , 131, 40021.