A Coarse-grained model for diffusion in zeolites based on clustering of short MD trajectories

Zeolites form a class of microporous aluminosilicates of great interest due to their multifarious applications in industry and everyday life. Their porous structure allows small molecules to be adsorbed and to diffuse inside crystals, and depending on the zeolite type and on the diffusant species a variety of behaviours is possible. Molecular Dynamics is now widely used in order to understand the microscopic mechanisms of adsorption and diffusion occurring within these materials as well as in MOFs and ZIFs. A major drawback of MD for this kind of systems is its high computational cost, so that coarse-grained methods, speeding up simulations without losing the essential features of dynamics, are valuable tools for exploring the behaviour of guest molecules on time and space scales hardly, if at all, reachable with ordinary MD. The first step in our proposed method is the clustering of MD trajectories to obtain a discretized version of the motion of adsorbed molecules within the zeolite. Each pore in the aluminosilicate is partitioned in a number of regions and each point in the original trajectory is mapped to the proper region based on a distance criterion. The regions correspond roughly to the main basins in the potential energy surface (PES)

Do victims of crime trust less but participate more in social organizations?

© The Author(s) 2019. We explore how crime victimization affects two of the main dimensions of social capital: trust and participation in social groups. Using a large database that includes many Latin American countries, we find that victimization lowers trust, especially in other people and the police. However, participation in social groups is increased as a result of this event. These findings suggest that the net effect of victimization on social capital is miscalculated unless all of its dimensions are taken into account

Evaluation of the energy utilization index in sheep milk cooling systems

The energy consumption of sheep milk cooling systems (MCSs) was quantified in this study to provide original information filling a literature gap on the impact of sheep milk cooling on the energy and economic balance in dairy farms. Performance and energy monitoring tests were conducted simultaneously on 22 MCSs in Sardinia (Italy). The results determined the cooling time as a function of the performance class and number of milkings. The Energy Utilization Index (EUI) was applied to measure the energy required to cool down the milk and estimate the incidence on its price. The average EUI was 1.76 kWh 100 L−1 for two-milkings and 2.43 kWh 100 L−1 for four-milkings MCSs, whereas the CO2 emissions ranged from 998 to 1378 g CO2 100 L−1 for two- and four-milkings MCSs, respectively. The estimated energy consumption for the storage of refrigerated sheep milk was 0.12 kWh 100 L−1. The malfunctioning MCSs averagely consumed 31% more energy than regular systems. The energy cost for cooling accounted for 0.61% on the current sheep milk price in Italy. Based on the analysis, the reported EUI values can be used as a preliminary indicator of the regular operation of MCSs

Effects of low vacuum levels on vacuum dynamics during milking

One of critical points of the milking unit is the short milk tube. Here milk plugs can cause abrupt variations in vacuum which are stressful for the animals. Our trials allowed us to define the effects of the operational vacuum and pulsation on vacuum stability in the short milk tube. Reducing the vacuum from 42 to 28 kPa did not produce appreciable variations in vacuum fluctuation. It was 9.2 kPa for the low vacuum and 9.8 kPa for the standard vacuum. Changing the pulsation rate from 150 to 120 cycles/min did not modify the vacuum stability in the short milk tube. By contrast, raising the pulsation ratio from 50% to 60% significantly increased the amplitude of vacuum fluctuation in the short milk tube

Inequality, crime and private protection

There is a consensus that inequality increases the supply of crime. As disparity in income grows within a society, the incentives for low-income individuals to engage in criminal activities also increase. However, in a context of high inequality, better-off individuals invest in deterring those who want to appropriate their resources. We examine this twofold effect of inequality in an equilibrium model of crime and private protection. We show that inequality unambiguously increases investment in private protection, but the relationship between inequality and crime is ambiguous, depending on how protection responds to private investment.Corvalan gratefully acknowledges financial support from the Institute for Research in Market Imperfections and Public Policy, MIPP (ICS13_002 ANID)

Migrant Diversity and Team Performance in a High-Skilled Labour Market

Data Availability Statement: The data that support the findings of this study are available from Panini Digital. Restrictions apply to the availability of these data, which were used under license for this study.Copyright © 2022 The Authors. From a theoretical point of view, the link between workplace diversity and performance in a high-skilled context is ambiguous. Likewise, empirical research at the firm or plant level finds inconclusive and context- specific results. Using a detailed database that covers all the 3,999 matches played by Italian Serie A teams (firms) over a 10-season period, our results reveal a substantial and robust negative effect of fractionalization on performance, whereas no effect is found for polarization. This article also highlights how the negative effect of fractionalization depends on the nature of the tasks to be completed, the wealth of the teams and the level of workers' experience. This work reveals some myopia in hiring practices and suggests that firms should make better decisions in choosing the optimal mix of workers.This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors

Migrant diversity and team performance in a high‐skilled labour market

From a theoretical point of view, the link between workplace diversity and performance in a high-skilled context is ambiguous. Likewise, empirical research at the firm or plant level finds inconclusive and contextspecific results. Using a detailed database that covers all matches played by Italian Serie A teams (firms) over a 10-season period, our results reveal a substantial and robust negative effect of fractionalization on performance, whereas no effect is found for polarization. This article also highlights how the negative effect of fractionalization depends on the nature of the tasks to be completed, the wealth of the teams and the level of workers’ experience. This work reveals some myopia in hiring practices and suggests that firms should make better decisions in choosing the optimal mix of workers