Measurements of ionization cross sections by molecular beam experiments: information content on the imaginary part of the optical potential

In this work, we present and analyze in detail new and recent ionization cross section and mass spectrum determinations, collected in the case of He*, Ne*-H2O, -H2S, and -NH3 ionizing collisions. These sets of data, obtained under the same experimental conditions, are relevant to identify differences in the autoionization stereodynamics of the three hydrogenated molecules and on the selective role of the imaginary part of the optical potential. We demonstrate that in these autoionization processes hydrogen and halogen bonds are competing because they are controlling both real and imaginary components of the optical potential that drives the complete reaction dynamics. In particular, we found that both components critically depend on the angular and radial approach between the reagent partners in determining the collision dynamics

Unsteady cfd analysis of erosion mechanism in the coolant channels of a rotating gas turbine blade

The two-phase flow in a rotating wedge mimicking the final portion of a blade turbine internal cooling channel is here presented and discussed focusing on unsteady motion and erosion mechanisms. The rotation axis is placed to properly reproduce a configuration with a very strong deviation (90°). The flow field was modelled by using the well known k---f unsteady-RANS model based on the elliptic-relaxation concept. The model was modified by some of the authors to take into account the influence of turbulence anisotropy as well as rotation. The model was applied to the well-established and fully validated T-FlowS code. A systematic comparison of rotating and non-rotating case was carried out to show the influence of Coriolis force on flow and erosion mechanisms. The rotational effects strongly changed the flow behaviour within the channel, affecting both the unsteady flow and the particles trajectories. In the rotating case, there is no recirculation on the tip region; besides, position of the small recirculation regions above each pedestals change. These, and other minor effects, affect the particle motion thus resulting in a different erosion pattern

A Basic Geometric Framework for Quasi-Static Mechanical Manipulation

In this work, we propose a geometric framework for analyzing mechanical manipulation, for example, by a robotic agent. Under the assumption of conservative forces and quasi-static manipulation, we use energy methods to derive a metric. We first review and show that the natural geometric setting is represented by the cotangent bundle and its Lagrangian submanifolds. These are standard concepts in geometric mechanics but usually presented within dynamical frameworks. We review the basic definitions from a static mechanics perspective and show how Lagrangian submanifolds are naturally derived from a first order analysis. Then, via a second order analysis, we derive the Hessian of total energy. As this is not necessarily positive-definite from a control perspective, we propose the use of the squared-Hessian for optimality measures, motivated by insights {derived from both mechanics (Gauss's Principle) and biology (Separation Principle)}. We conclude by showing how such methods can be applied, for example, to the simple case of an elastically driven pendulum. The example is simple enough to allow for analytical solution. However, an extension is further derived and numerically solved, which is more realistically connected with actual robotic manipulation problems.Comment: 28 pages, 6 figures, 1 tabl

HENVINET. Evaluation questionnaire - causal chain for cancer.

The HENVINET consortium has developed a questionnaire to identify knowledge gaps in the state of the art in scientific knowledge. Literature reviews covered all elements that compose the causal chain of the different environmental health issues from emissions to exposures, to effects and to health impacts. Ultimately, the aim is to discuss the implications of these for policy and research. In this evaluation we focus on various aspects of the cause-effect relationship between our living environment and increased risk of cancer development. Occupational exposure to carcinogens is not included. Six cancer types are considered; brain cancer, breast tumors, colorectal tumors, leukemia, lung mesothelioma and melanoma

Luigi Pagliaro, Marco Bobbio, Agostino Colli: Diagnosis in Medicine

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Endowment effects at different time scenarios: the role of ownership and possession

The central issue of the wide literature about the endowment effect is the search for an explanation of the fact that the selling price of a good will be higher than that at which a person is willing to buy that same good, once they own it. The experimental evidence is not unanimous in replicating the results found by Kahneman et al. (1990 and 1991). The challenge is that of disentangling the several determinants that may be at work in generating the final effect, as the loss aversion is not considered the only explanation. We dig deeper by examining two of these likely determinants which remain understudied: the first is the impact that the amount of time of ownership can have on the endowment effect. The second is the type of item (non-material good and exchange goods) used to test the effect. Through an online questionnaire we investigate these aspects by using three different goods: a mug, an Amazon Gift Card and a quarterly subscription to Spotify. We also test whether the endowment effect occurs in different time scenarios, that is if participants imagine to own the good for one day, one week or one month. We find that the endowment effect clearly appears for all types of goods while less clear results take shape when considering the duration of the ownership

Coherent transport in extremely underdoped Nd1.2Ba1.8Cu3Oz nanostructures

Proximity-effect and resistance magneto-fluctuations measurements in submicron Nd1.2Ba1.8Cu3Oz (NBCO) nano-loops are reported to investigate coherent charge transport in the non-superconducting state. We find an unexpected inhibition of cooper pair transport, and a destruction of the induced superconductivity, by lowering the temperature from 6K to 250mK. This effect is accompanied by a significant change in the conductance-voltage characteristics and in the zero bias conductance response to the magnetic field pointing to the activation of a strong pair breaking mechanism at lower temperature. The data are discussed in the framework of mesoscopic effects specific to superconducting nanostructures, proximity effect and high temperature superconductivity.Comment: to appear on new journal of Physic

Assessment of innovative reforming procedures for biogas obtained from organic fraction of solid municipal waste

In the present paper reforming technologies for the treatment of biogas from municipal solid wastes are discussed. An approach based on the well-known ASPEN Plus software was adopted for the simulation of the whole process, assuming equilibrium conditions for the reactions development. The well-established steam-reforming, the dry reforming and an innovative two-steps reforming (including the basics of both models) were considered. A preliminary assessment was carried out comparing the predictions and experimental results of the steam-reforming procedure of diesel fuel. Then, the validated model was applied to the different schemes. The dry reforming (at 800 °C) showed better reforming efficiency if compared to steam reforming (at 600°C). However, carbon deposition occurs when dry reforming is in play. On the other hand, the two-steps technique demonstrated to be able to solve the problem of carbon deposition guaranteeing a very good efficiency

Five shades of women: evidence from Italian listed firms

Purpose This paper aims to examine empirically the impact of gender diversity on corporate performance by both comparing different positions occupied by female directors on the boards and their personal-specific characteristics. Design/methodology/approach The paper examines a sample of Italian listed companies during 2006\u20132015. To deal with endogeneity issues, the authors use a generalized method of moments as an empirical methodology. Findings The empirical findings show that the positive effect of both independent and executive women directors on firm performance is moderated by the specific characteristics of female directors. Specifically, the analyses show that foreign and busy females negatively impact on performance. Conversely, graduate female directors strengthen the positive link between executive women and firm performance. Originality/value The paper sheds light on the consequences of appointing different types of female directors (i.e. independent, executive, graduate, foreign and busy) on firm performance. Our empirical research that investigates the association between gender diversity and performance in the Italian context based on a longitudinal study, which involves a period of ten\u2009years, allowing consideration both of the years before and after the introduction of the gender quota law (Golfo\u2013Mosca law)