Global shifts: U. S. immigration and the cultural impact of demographic change

At the turn of the millennium, we are witnessing intense new worldwide migration and refugee flows. There are now some 100 million transnational immigrants plus an estimated 30 million refugees displaced from their homelands. These flows are largely structured by the intensification of globalization--a process of economic, social, and cultural transformation rapidly accelerating in the last decade. Globalization has increased immigration in a variety of ways. First, transnational capital flows (roughly a trillion dollars cross national boundaries every day) tend to stimulate migration because where capital flows, immigrants tend to follow. Second, the new information and communication technologies that are at the heart of globalization tend to stimulate migration because they encourage new standards of consumption and life-style choices. Would-be immigrants imagine better opportunities elsewhere and mobilize to achieve them. Third, the affordability of mass transportation--last year approximately 1.5 billion airline tickets were sold--has put the migration option within the reach of millions who heretofore could not consider it. Fourth, globalization has stimulated new migration because it has produced uneven results--big winners and losers.Demography ; Economic conditions ; Emigration and immigration

Rauiella niveo-calycina es un sinónimo nuevo de R. praelonga

Rauiella niveo-calycina (Müll. Hal) Wijk & Marg. is proposed as a new synonym of R. praelonga (Schimp. ex Besch) Wijk & Marg. The species treated is discussed briefly.Rauiella niveo-calycina es un sinónimo nuevo de R. praelonga. R. niveo-calycina (Müll. Hal) Wijk & Marg. es propuesta en este trabajo como un sinónimo nuevo de R. praelonga (Schimp. ex Besch) Wijk & Marg. La especie tratada es brevemente discutida.Fil: Suarez, Guillermo Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; ArgentinaFil: Schiavone, María M.. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; Argentin

Modelling take-up of Family Credit and Working Families' Tax Credit

Many people in the UK do not claim benefits to which they seem to be entitled. Amongst those of working-age, take-up rates for Family Credit ֠an in-work benefit available to those with children and working at least 16 hours a week ֠were the lowest of the main three means-tested benefits. In 1999, the UK Government replaced Family Credit with Working Families' Tax Credit, which was more generous, and delivered in a different way from FC. As a prelude to further work (now published as an update to this in the final report), we have analysed the decision to take up FC, and how take-up changed during the initial 6 month phase-in period of WFTC. Although there are differences in how well each records receipt of FC, we find reassuring similarities in comparable econometric models of take-up estimated on three different micro-data-sets. Entitlement, earnings, non-labour income, and education attainment are the most important determinants of FC take-up. We investigated FC take-up in greater detail using only the Family Resources Survey. Social renters are more likely to claim FC than owner occupiers or those in the private rental market, and we find that housing benefit recipients seem to under-value the potential fall in HB when considering whether to claim FC. We find that the Family Credit childcare disregard had little impact on the likelihood of take-up. Take-up of WFTC, conditional on entitlement, fell immediately after its introduction, compared to FC, but the majority of the effect is explained by the relatively low take-up rates of those families who were not previously entitled to FC. This is unsurprising, as we would not expect this group to have claimed WFTC on the first day of its existence. Work currently in progress is examining how take-up of WFTC, and the factors associated with take-up, changed between April 2000 and March 2003

Intrinsic Magnetism in Nanosheets of SnO2_{2}: A First-principles Study

We propose intrinsic magnetism in nanosheets of SnO$_{2}$, based on first-principles calculations. The electronic structure and spin density reveal that $p$ orbitals of the oxygen atoms, surrounding Sn vacancies, have a non itinerant nature which gives birth to localized magnetism. A giant decrease in defect formation energies of Sn vacancies in nanosheets is observed. We, therefore, believe that native defects can be stabilized without any chemical doping. Nanosheets of different thicknesses are also studied, and it is found that it is easier to create vacancies, which are magnetic, at the surface of the sheets. SnO$_{2}$ nanosheets can, therefore, open new opportunities in the field of spintronics.Comment: J. Magn. Magn. Mate. 2012 (Accepted

Did working families' tax credit work? The final evaluation of the impact of in-work support on parents' labour supply and take-up behaviour in the UK

With micro-data from before and after a major reform in 1999 to the structure and form of in-work transfers in the UK, this paper uses a structural model of labour supply and programme participation to evaluate the labour market impact of Working Families' Tax Credit (WFTC). Estimates suggest that by 2002, WFTC had increased labour supply of lone mothers by around 5.11 percentage points, slightly reduced labour supply of mothers in couples by 0.57 percentage points, and increased the labour supply of fathers in couples by 0.75 percentage points, compared with the benefit that preceded it, called Family Credit. In aggregate, these changes are equivalent to a fall of 99,000 in the number of workless families with children, and a net increase in labour market participation of 81,000 workers. However, contemporaneous tax and benefit reforms acted to reduce the labour supply of parents, and so the overall impact of tax and benefit changes introduced since 1999 is lower than stated above. Participating in Family Credit, the UK's in-work programme before October 1999, conferred a utility loss as well as a utility gain from the extra income, but we find this utility cost of participation to be lower in the final year of WFTC than it was in the last year of Family Credit for lone mothers, and no different for individuals in couples: this in itself induced more lone mothers to work

Did Working Families' Tax Credit work? Analysing the impact of in-work support on labour supply and programme participation

With micro-data from before and after a major reform in 1999 to the structure and form of in-work transfers in the UK, this paper uses a structural model of labour supply and programme participation to show the impact of a reform to in-work support (Working Families' Tax Credit) on both labour supply and programme participation (or take-up). Estimates suggest that the changes in in-work incomes through the introduction of WFTC increased labour supply of lone mothers by around 4.6 percentage points, slightly reduced labour supply of mothers in couples by 0.2 percentage points, and increased the labour supply of fathers in couples by 0.8 percentage points, equivalent to a net increase in participation of 94,000 workers. Participating in Family Credit, the UK's in-work programme before October 1999, conferred a utility loss as well as a utility gain from the extra income, but we find this utility cost of participation to be lower under WFTC

The role of rotation on Petersen Diagrams. The Pi1/0(Omega) Pi_{1/0}(Omega) period ratios

The present work explores the theoretical effects of rotation in calculating the period ratios of double-mode radial pulsating stars with special emphasis on high-amplitude delta Scuti stars (HADS). Diagrams showing these period ratios vs. periods of the fundamental radial mode have been employed as a good tracer of non-solar metallicities and are known as Petersen diagrams (PD).In this paper we consider the effect of moderate rotation on both evolutionary models and oscillation frequencies and we show that such effects cannot be completely neglected as it has been done until now. In particular it is found that even for low-to-moderate rotational velocities (15-50 km/s), differences in period ratios of some hundredths can be found. The main consequence is therefore the confusion scenario generated when trying to fit the metallicity of a given star using this diagram without a previous knowledge of its rotational velocity.Comment: A&A in pres

Reset and switch protocols at Landauer limit in a graphene buckled ribbon

Heat produced during a reset operation is meant to show a fundamental bound known as Landauer limit, while simple switch operations have an expected minimum amount of produced heat equal to zero. However, in both cases, present-day technology realizations dissipate far beyond these theoretical limits. In this paper we present a study based on molecular dynamics simulations, where reset and switch protocols are applied on a graphene buckled ribbon, employed here as a nano electromechanical switch working at the thermodynamic limit