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The Plio-Pleistocene El Laco magnetite ore bodies in the Chilean Altiplano represent an unusual subvolcanic/aerial type of an iron oxide-apatite (IOA) deposit. The textures of these magnetite ore bodies have sustained a long-standing geological controversy on the origin of iron oxide deposits with models spanning the spectrum from purely igneous to magmatic-hydrothermal processes. In particular, the link between the geochemical processes taking place in the source magma and the subsequent evolution of the overlying magmatic-hydrothermal system are still not well understood. Here we address this problem by focusing on microtextural and geochemical features of iron ore and silicate gangue minerals retrieved from drill core samples from El Laco ore bodies, as well as from the andesite volcanic host rocks. We report a comprehensive geochemical dataset of magnetite assemblages at El Laco obtained using a combination of EPMA, LA-ICP-MS, and synchrotron radiation µ-XRF methods. Microtextural and geochemical data of magnetite reveal consistent variations with depth. Magnetite in the andesitic host rocks and from deep/intermediate levels of the ore bodies have a high concentration of trace elements including Ti, V, Ni, Mn, Zn, Cr, Al, Ga, Cu and Co in comparison with magnetite from the upper sections of the ore bodies. Clinopyroxene is present in the andesite host rocks as well as the ore bodies, showing chemical differences between both types, with Mn and Fe contents that are higher in the former, and Na and Ca concentrations enriched in the latter. We interpret the enriched-to-depleted compositional trends in magnetite and clinopyroxene as resulting from a transition from purely igneous conditions to a fluid-dominated, cooling magmatic-hydrothermal system. Detailed microtextural analysis of magnetite and clinopyroxene from the ore bodies support this notion, revealing multiple growth stages punctuated by dissolution-reprecipitation processes. Our data further supports a genetic model that explains the formation of the El Laco iron oxide deposit through the injection, upward migration and venting of magmatically-derived Fe-rich fluids. [ABSTRACT FROM AUTHOR]

Abstract We show how to decoupling two spherically symmetric and static gravitational sources through the most general possible extension of the so-called Minimal Geometric Deformation-decoupling. As a test, we decouple the Einstein–Maxwell system and reproduce the Reissner–Nordstrom solution. We show the potential of this method to study i) the consequences of modified gravity on general relativity, ii) to investigate the conjectured dark matter, and iii) to study hairy black holes. [ABSTRACT FROM AUTHOR]

Abstract: We study stars in the brane-world by employing the principle of minimal geometric deformation and find that brane-world black hole metrics with a tidal charge can be consistently recovered in a suitable limit. This procedure allows us to determine the tidal charge as a function of the ADM mass of the black hole (and brane tension). A minimum mass for semiclassical microscopic black holes can then be derived, with a relevant impact for the description of black hole events at the LHC. [Copyright &y& Elsevier]

Purpose Development of cancer is recognized as one of the main causes of death after lung transplantation. We aimed to propose an equation for cancer risk after lung transplantation. Methods Retrospective study of all cases of cancer diagnosed in a Spanish Transplant Unit between 1999 and 2017. A control group consisted of lung transplant patients that did not develop cancer during the follow-up, matched by date of lung transplantation. The excess risk of cancer was calculated as odds ratio, being the best equation selected that which uses the allsets method with subsequent inclusion of the parameters in a logistic regression. Survival curves were analyzed with Kaplan-Meier. The statistical analysis was done with Stata 14.2 Results Out of 630 lung transplantations, 48 cancers were diagnosed: 11 skin (22.92%), 8 lymphoma (16.67%), 8 lung (16.67%), 7 gastrointestinal (14.58%) and 7 others (14.58%). There were no significant differences regarding: indication for lung transplantation (p 0.86), age (p 0.50), gender (p 0.09), follow-up time (p 0.84), acute rejection (p 0.58), chronic rejection (p 0.69) or immunosupprive regimen (p 0.22). In the univariate analysis, cancer development was associated with cytomegalovirus infection/disease (p 0.005) and bilateral lung transplant (p 0.01). In the multivariate analysis adjusted for gender according to allsets method CMV infection/disease had an OR of 3.83 (95% IC 1.31-11.13), bilateral comparing to single lung transplant had an OR of 0.38 (95% IC 0.15-0.97) and men comparing to women had an OR of 1.67 (95% IC 0.78-4.80). A final risk equation for cancer after lung transplantation was developed, as follows: p(cancer)= -0,38 + (1,34 x CMV) + (-0,96 x lung transplant type)+(0,52 x gender). Conclusion CMV infection/disease and the type of lung transplant procedure were strong predictors for the development of cancer. There is a need to identify specific tests that permit early diagnosis of the most frequent cancers in these high-risk patients. [ABSTRACT FROM AUTHOR]