Locational choices of return migrants to Spain: Capital markets, savings, investment, and regional variation

Depending on the activities a migrant plans to undertake in his home country and what he has achieved abroad, regional variations should result in different rates of return to region of origin for emigrants. I analyze this choice of home-country destination by returning emigrants with data on former guestworkers currently in urban areas of Spain in 1978. I test to see if spatial variations in the rate of interest, as a result of spatially imperfect capital markets, contribute to an emigrant\u27s probability of returning to his native province. The interaction of the effects of return migrants\u27 savings and investment with the effects of local mortgage interest rates on the probabilities of return to region of birth are measured using a binomial logit of the probability of return to region of birth. In order to evaluate variation in the cost of purchasing a house across regions, I rely on the indicator of urban mortgage interest rates. By controlling for regional mortgage interest rates in estimating the logit equation, I examine whether return migrants respond to differences in the cost of purchasing a house across regions. The results of this analysis provide indirect evidence that return migrants with savings are sensitive to interest rates because a greater likelihood of return to region of birth is correlated with higher levels of savings and return to high-rate areas. Migrants who, due to low levels of savings, purchase a house with credit are indifferent between low-rate areas and high-rate ones, and are less likely to return home. Return to place of birth is more likely if a migrant has cash to invest in a house purchase and local mortgage interest rates are relatively high. The average rate of return to region of birth is slightly higher than 50%. However, rates of return vary widely by region. Although, a significant portion of the variation in rates of return is explained by differences in the level of local development, another significant proportion of the variation can be explained by controlling for savings from sojourn abroad, current housing status in Spain, and local mortgage interest rates

Dissected hydrologic system at the Grand Canyon: Interaction between deeply derived fluids and plateau aquifer waters in modern springs and travertine

Geochemical study of water and gas discharging from the deeply incised aquifer system at the Grand Canyon, Arizona, provides a paradigm for understanding complex groundwater mixing phenomena, and Quaternary travertines deposited from cool springs provide a paleohydrologic record of this mixing. Geochemical data show that springs have marked compositional variability: those associated with active travertine accumulations (deeply derived endogenic waters) are more saline, richer in CO2, and elevated in 87Sr/86Sr relative to springs derived dominantly from surface recharge of plateau aquifers (epigenic waters). Endogenic waters and associated travertine are preferentially located along basement-penetrating faults. We propose a model whereby deeply derived fluids are conveyed upward via both magmatism and seismicity. Our model is supported by: (1) gas analyses from spring waters with high He/Ar and He/N2 and 3He/4He ratios indicating the presence of mantle-derived He; (2) large volumes of travertine and CO2-rich gases in springs recording high CO2 fluxes; and (3) 87Sr/86Sr in these springs that indicate circulation of waters through Precambrian basement. Geochemical trends are explained by mixing of epigenic waters of the Colorado Plateau aquifers with different endogenic end-member waters in different tectonic subprovinces. Endogenic waters are volumetrically minor but have significant effects on water chemistry. They are an important and largely unrecognized component of the hydrogeochemistry and neotectonics of the southwestern United States

Biographies of international women leaders in neurosurgery

We received so many biographies of women neurosurgery leaders for this issue that only a selection could be condensed here. In all of them, the essence of a leader shines through. Many are included as “first” of their country or color or other achievement. All of them are included as outstanding—in clinical, academic, and organized neurosurgery. Two defining features are tenacity and service. When faced with shocking discrimination, or numbing indifference, they ignored it or fought valiantly. When choosing their life’s work, they chose service, often of the most neglected—those with pain, trauma, and disability. These women inspire and point the way to a time when the term “women leaders” as an exception is unnecessary