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)

Size matters: measuring the private security industry in the United Kingdom

The private security industry has become a central feature of the plural policing landscape in the United Kingdom. As such, it has received considerable attention in both academic and policy circles. Yet, perhaps surprisingly, there remain notable question marks over its precise size and shape. With this in mind, the article draws upon data from the Security Industry Authority and the Office of National Statistics Business Register and Employment Survey to measure the sector along three key dimensions: the number of private security officers, the number of companies and turnover. This novel methodological approach reveals a complex and contested picture of what the sector looks like at a fundamental level and, at the same time, allows for a reassessment of commonly deployed indicators such as growth rates and the ratio of private security officers to police officers during key time periods such as the Covid-19 pandemic

New Evidence on Post-Brexit UK Migration Trends

This report was issued in June 2024 by Brunel University London. Centre for Law, Economics and Finance, available online at: https://www.brunel.ac.uk/research/Documents/centre-for-law-economics-and-finance/2024-Post-Brexit-Migration-Report.pdf . This report expands on the range of inquiries and issues addressed by the Manifesto di Londra association over the past four years. Matteo and Federico extend their gratitude to the members of the association’s Migration Committee for their valuable insights and support.At foot of title page: Report – May 2024.The report co-authored by Dr Federico Filauri, Dr Matteo Pazzona and Dr Matilde Rosina provides new evidence on post-Brexit UK migration trends up to December 2023. The report analyses recent migration patterns, highlighting the complex interplay between policy changes, economic factors, and global events in shaping UK migration trends.:Key findings: • In December 2023, net migration was 685,000, a 10% decrease from its all-time high in December 2022 (764,000), but still a 47% increase compared to December 2021 (466,000). Among internationals, 41% immigrated to the UK to work, 34% to study, 7% for family reasons, 11% for humanitarian and asylum, and 6% for other reasons. • In December 2023, the Department for Work and Pensions recorded more than 1.11 million new NiNo registrations from internationals, comparable with 1.05 million in 2022, with non-EU nationals accounting for 91% of the total (led by India and Nigeria), and EU for the remaining 9% (led by Romania). Between 2022 and 2023 there has been a 46% rise in the granting of work visa, amounting to 616,371 in 2023. • In 2023, the number of new international students marked a 3% decrease, for a total of 340,990. This is consistent with the 3% drop in study visa grants, which amounted to 605,504 in 2023. However, last year, almost a quarter (24%) of study visas have been granted to a dependant, a significant rise from the 4% in 2019. • The number of small boat arrivals totalled 29,437, marking a 36% decrease compared to the previous year, and in line with 2021. The decline in 2023 is mainly driven by a vertical drop in the number of Albanian migrants, which decreased by 93%. Humanitarian visa grants amounted to 102,283 in 2023, almost half of which were on Ukraine schemes. However, the latter marked an 80% decrease compared to the previous year, which drove down the number of humanitarian visa grants by approximately two thirds. • In 2023, there were 81,203 family-related visas granted in 2023, a 72% increase from last year and an all-time high.The research for the current report was made possible by Brunel University’s Centre for Law, Economics, and Finance. The authors gratefully acknowledge the financial and technical support provided by CLEF