Integrated population models poorly estimate the demographic contribution of immigration

Estimating the contribution of demographic parameters to changes in population growth is essential for understanding why populations fluctuate. Integrated population models (IPMs) offer a possibility to estimate the contributions of additional demographic parameters, for which no data have been explicitly collected—typically immigration. Such parameters are often subsequently highlighted as important drivers of population growth. Yet, accuracy in estimating their temporal variation, and consequently their contribution to changes in population growth rate, has not been investigated. To quantify the magnitude and cause of potential biases when estimating the contribution of immigration using IPMs, we simulated data (using northern wheatear Oenanthe oenanthe population estimates) from controlled scenarios to examine potential biases and how they depend on IPM parameterization, formulation of priors, the level of temporal variation in immigration and sample size. We also used empirical data on populations with known rates of immigration: Soay sheep Ovis aries and Mauritius kestrel Falco punctatus with zero immigration and grey wolf Canis lupus in Scandinavia with near-zero immigration. IPMs strongly overestimated the contribution of immigration to changes in population growth in scenarios when immigration was simulated with zero temporal variation (proportion of variance attributed to immigration = 63% for the more constrained formulation and real sample size) and in the wild populations, where the true number of immigrants was zero or near-zero (kestrel 19.1%–98.2%, sheep 4.2%–36.1% and wolf 84.0%–99.2%). Although the estimation of the contribution of immigration in the simulation study became more accurate with increasing temporal variation and sample size, it was often not possible to distinguish between an accurate estimation from data with high temporal variation versus an overestimation from data with low temporal variation. Unrealistically, large sample sizes may be required to estimate the contribution of immigration well. To minimize the risk of overestimating the contribution of immigration (or any additional parameter) in IPMs, we recommend to: (a) look for evidence of variation in immigration before investigating its contribution to population growth, (b) simulate and model data for comparison to the real data and (c) use explicit data on immigration when possible

Towards constraints on the SUSY seesaw from flavour-dependent leptogenesis

We systematically investigate constraints on the parameters of the supersymmetric type-I seesaw mechanism from the requirement of successful thermal leptogenesis in the presence of upper bounds on the reheat temperature $T_\mathrm{RH}$ of the early Universe. To this end, we solve the flavour-dependent Boltzmann equations in the MSSM, extended to include reheating. With conservative bounds on $T_\mathrm{RH}$, leading to mildly constrained scenarios for thermal leptogenesis, compatibility with observation can be obtained for extensive new regions of the parameter space, due to flavour-dependent effects. On the other hand, focusing on (normal) hierarchical light and heavy neutrinos, the hypothesis that there is no CP violation associated with the right-handed neutrino sector, and that leptogenesis exclusively arises from the CP-violating phases of the $U_\text{MNS}$ matrix, is only marginally consistent. Taking into account stricter bounds on $T_\mathrm{RH}$ further suggests that (additional) sources of CP violation must arise from the right-handed neutrino sector, further implying stronger constraints for the right-handed neutrino parameters.Comment: 42 pages, 12 figures; final version published in JCAP; numerical results for the efficiency factor can be downloaded from http://www.newphysics.eu/leptogenesis

BOB-RED queue management for IEEE 802.15.4 wireless sensor networks

This study is aimed at exploring why many economists propose a transfer scheme and debt mutualisation for the Eurozone. This would equip the Eurozone with better tools to deal with an economic shock, like the 2010-2012 sovereign debt crisis, thus making it more financially stable. After the theoretical presentation, the study presents a unique institutional design with an EU Treasury that manages debt mutualisation and a transfer scheme as well as other competences that address other present economic challenges. Crucial to the study are the issues of moral hazard and adverse selection that arise when thinking of European economic integration.L’objectiu del treball és explorar la raó per la qual molts economistes proposen un sistema de transferències fiscals i la mutualització del deute a l’Eurozona. Així se la dotaria amb eines més efectives per pal·liar un xoc econòmic, com la crisi del deute sobirà del 2010-2012. A continuació, es presenta un disseny institucional únic d’un Tresor de l’Euro que gestionaria les competències esmentades (i d’altres) per combatre alguns dels reptes econòmics actuals. El risc moral i de selecció adversa, qüestions que sorgeixen en pensar la drecera que ha de prendre la integració econòmica Europea, són cabdals per aquest estudi

Improving the public house in Britain, 1920-40: Sir Sydney Nevile and 'social work'

The ‘improved public house’ movement in the inter-war years was a central part of the shift towards retailing by the brewing industry. An important part of the reform movement was the alliance between certain brewers, notably Whitbread, and ‘social workers’, particularly those associated with the University settlement movement in London. Using the papers of Sydney Nevile, the importance of a particular social milieu is outlined, calling into question attempts to align the movement to improve public houses with transatlantic Progressivism. Rather, this alliance drew upon longstanding English traditions of public service and religious affiliation amongst a fraction of the gentry

Fatigue assessment of a railway bridge detail using dynamic analysis and probabilistic fracture mechanics

This paper presents a generic methodology for the use of PFM within the context of bridge loading for the fatigue design and assessment of steel railway bridges and provides detailed guidance on how to use the proposed methodology in order to carry out a PFM-based fatigue assessment. The problem is set in a probabilistic context to take into account material, loading as well as modeling uncertainties. Guidance is given on how to calibrate a constant amplitude PFM analysis against an S-N curve. Finally, as a case study, a cracked welded bridge detail is considered and its time-dependent fatigue reliability is established © 2012 Taylor & Francis Group

Mezcla génica y linajes uniparentales en Comodoro Rivadavia

En este estudio nos propusimos: 1) estimar la mezcla génica en una muestra de Comodoro Rivadavia analizando 6 sistemas sanguíneos en 72 dadores de sangre, no emparentados, que concurrieron al Hospital Regional, 2) evaluar la contribución de los linajes maternos y paternos amerindios a partir del estudio del ADN mitocondrial y Cromosoma Y. Las frecuencias génicas se calcularon con métodos de máxima verosimilitud para los marcadores proteicos y por conteo directo para los uniparentales. La mezcla génica se estimó mediante el Programa ADMIX. Se obtuvieron datos genealógicos e informes sobre lugar de residencia y origen de los donantes. Se registró un 37% de aporte indígena y un 4% de africano. A un origen amerindio fueron adscriptos el 70% de los linajes maternos y el 6% de los paternos. Esta diferencia en la contribución genética sexo-específica estaría revelando un aporte asimétrico por género en la historia de esta población. Se comparan estos resultados con los obtenidos con anterioridad en Buenos Aires y Bahía Blanca.Simposio: Genética de poblaciones neoamericanas.Asociación de Antropología Biológica de la República Argentina (AABRA

Mezcla génica y linajes uniparentales en Comodoro Rivadavia

En este estudio nos propusimos: 1) estimar la mezcla génica en una muestra de Comodoro Rivadavia analizando 6 sistemas sanguíneos en 72 dadores de sangre, no emparentados, que concurrieron al Hospital Regional, 2) evaluar la contribución de los linajes maternos y paternos amerindios a partir del estudio del ADN mitocondrial y Cromosoma Y. Las frecuencias génicas se calcularon con métodos de máxima verosimilitud para los marcadores proteicos y por conteo directo para los uniparentales. La mezcla génica se estimó mediante el Programa ADMIX. Se obtuvieron datos genealógicos e informes sobre lugar de residencia y origen de los donantes. Se registró un 37% de aporte indígena y un 4% de africano. A un origen amerindio fueron adscriptos el 70% de los linajes maternos y el 6% de los paternos. Esta diferencia en la contribución genética sexo-específica estaría revelando un aporte asimétrico por género en la historia de esta población. Se comparan estos resultados con los obtenidos con anterioridad en Buenos Aires y Bahía Blanca.Simposio: Genética de poblaciones neoamericanas.Asociación de Antropología Biológica de la República Argentina (AABRA

‘Here to support anybody who needs to come’? An investigation of the provision for EAL pupils in secondary school libraries in England

This paper presents the findings of a mixed methods investigation of the effectiveness of provision for EAL pupils by secondary school libraries in England. Data from a quantitative survey of secondary school librarians are triangulated with those of qualitative interviews with staff responsible for EAL provision. A picture emerges of a hybrid environment which addresses a number of the educational, cultural and social needs of EAL learners, but in which a series of barriers to effective provision are also identified. Recommendations are made to key stakeholder groups for the short and long term improvement of EAL provision, and for further research