Selection in initial and return migration: Evidence from moves across Spanish cities

This paper investigates the sorting of more productive workers into denser cities using administrative data for Spain that follow individuals continuously throughout their working lives. Migrants who move to denser cities are positively selected in terms of education, occupational skills, and individual productivity as proxied by premigration position in the local earnings distribution. However, not everyone is able to benefit equally from denser cities and this leads to a second round of sorting. Returnees are not only exante less productive than permanent migrants, but are also those who, following the first move, have least boosted up their earnings in denser cities.selection; urban migration; return migration; skill sorting

City of dreams

Bigger cities offer more valuable experiences and opportunities in exchange for higher housing costs. While higher-ability workers benefit more from bigger cities, they are not more likely to move to one. Our model of urban sorting by workers with heterogeneous self-confidence and ability suggests flawed self-assessment is partly to blame. Analysis of the National Longitudinal Survey of Youth 1979 data shows that, consistent with our model, young workers with high self-confidence are more likely to locate in a big city initially. For more experienced workers, ability plays a stronger role in determining location choices, but the lasting impact of earlier choices dampens their incentives to move

City of dreams

Higher ability workers benefit more from bigger cities while housing costs there are higher for everyone, and yet there is little sorting on ability. A possible explanation is that young individuals have an imperfect assessment of their ability, and, when they learn about it, early decisions have had a lasting impact and reduce their incentives to move. We formalize this idea through an overlapping generations model of urban sorting by workers with heterogenous ability and self-confidence, with the latter defined as individuals’ assessment of their own ability. We then test the location patterns predicted by the model over the life cycle on panel data from the National Longitudinal Survey of Youth 1979. We find that the city-size choices of individuals at different stages vary with ability and self-confidence in a way that closely matches our theoretical predictions

Predictive Control Applied to a Solar Desalination Plant Connected to a Greenhouse with Daily Variation of Irrigation Water Demand

The water deficit in the Mediterranean area is a known matter severely affecting agriculture. One way to avoid the aquifers’ exploitation is to supply water to crops by using thermal desalination processes. Moreover, in order to guarantee long-term sustainability, the required thermal energy for the desalination process can be provided by solar energy. This paper shows simulations for a case study in which a solar multi-effect distillation plant produces water for irrigation purposes. Detailed models of the involved systems are the base of a predictive controller to operate the desalination plant and fulfil the water demanded by the crops

Modelo de orientación vocacional para instituciones educativas en Colombia /

Este libro contiene los resultados del proyecto “Movilizando la Educación Superior en el Departamento del Atlántico”, financiado por el Ministerio de Educación Nacional de Colombia, con el fin abordar, como caso de estudio, la demanda, la oferta y las estrategias de fortalecimiento del capital humano en este departamento del Caribe colombiano. El propósito final de la investigación fue configurar una propuesta de Modelo de Orientación Vocacional que ayude al proceso de acompañamiento de selección de programas formativos en los niveles técnico y tecnológico de los estudiantes de media vocacional en el país, de acuerdo con las necesidades que existen en sectores productivos estratégicos previamente identificadosEditorial Universidad del Nort

New Eremophilane-Type Sesquiterpenes from the Marine Sediment-Derived Fungus Emericellopsis maritima BC17 and Their Cytotoxic and Antimicrobial Activities

The fungal strain BC17 was isolated from sediments collected in the intertidal zone of the inner Bay of Cadiz and characterized as Emericellopsis maritima. On the basis of the one strain–many compounds (OSMAC) approach, four new eremophilane-type sesquiterpenes (1–4), together with thirteen known derivatives (5–17) and two reported diketopiperazines (18, 19), were isolated from this strain. The chemical structures and absolute configurations of the new compounds were determined through extensive NMR and HRESIMS spectroscopic studies and ECD calculation. Thirteen of the isolated eremophilanes were examined for cytotoxic and antimicrobial activities. PR toxin (16) exhibited cytotoxic activity against HepG2, MCF-7, A549, A2058, and Mia PaCa-2 human cancer cell lines with IC50 values ranging from 3.75 to 33.44 µM. (+)-Aristolochene (10) exhibited selective activity against the fungal strains Aspergillus fumigatus ATCC46645 and Candida albicans ATCC64124 at 471 µM