Geology, age and tectonic evolution of the Sierra Maestra Mountains, southeastern Cuba

We summarize the available geological information on the Sierra Maestra Mountains in southeastern Cuba and report new zircon fission track and biotite Ar-Ar ages for this region. Two different and genetically unrelated volcanic arc sequences occur in the Sierra Maestra, one Cretaceous in age (pre-Maastrichtian) and restricted to a few outcrops on the southern coast, and the other Palaeogene in age, forming the main expression of the mountain range. These two sequences are overlain by middle to late Eocene siliciclastic, carbonatic and terrigenous rocks as well as by late Miocene to Quaternary deposits exposed on the southern flank of the mountain range. These rocks are britle deformed and contain extension gashes filled with calcite and karst material. The Palaeogene volcanic arc successions were intruded by calc-alkaline, low- to medium-K tonalites and trondhjemites during the final stages of subduction and subsequent collision of the Caribbean oceanic plate with the North American continental plate. U-Pb SHRIMP single zircon dating of five granitoid plutons yielded 206Pb/238U emplacement ages between 60.5 ± 2.2 and 48.3 ± 0.5 Ma. These granitoids were emplaced at pressures ranging from 1.8 to 3.0 kbar, corresponding to depths of ca. 4.5-8 km. 40Ar/39Ar dating of two biotite concentrates yielded ages of 50 ± 2 and 54 ± 4 Ma, indicating cooling through ca. 300 ºC. Zircon and apatite fission track ages range from 32 ± 3 to 46 ± 4 Ma and 31 ± 10 to 44 ± 13 Ma, respectively, and date cooling through 250 ± 50 ºC and 110 ± 20 ºC. The granitoids are the result of subduction-related magmatism and have geochemical characteristics similar to those of magmas from intra-oceanic island-arcs such as the Izu Bonin-Mariana arc and the New Britain island arc. Major and trace element patterns suggest evolution of these rocks from a single magmatic source. Geochemical features characterize these rocks as typical subduction-related granitoids as found worldwide in intra-oceanic arcs, and they probably formed through fractional crystallization of mantlederived low- to medium-K basalts. Several distinct phases of deformation were recognized in the Sierra Maestra, labelled D1 to D6, which define the transition from collision of the Palaeogene island arc to the formation of the Oriente Transform Wrench Corridor south of Cuba and later movement of the Caribbean plate against the North American plate. The first phase (D1) is related to the intrusion of a set of extensive subparallel, N-trending subvertical basalt-andesite dykes, probably during the early to middle Eocene. Between the late-middle Eocene and early Oligocene (D2), rocks of the Sierra Maestra were deformed by approximately east-west trending folds and north-vergent thrust faults. This deformation (D2) was linked to a shift in the stress regime of the Caribbean plate from mainly NNE-SSW to E-W. This shift in plate motion caused the abandonment of the Nipe-Guacanayabo fault system in the early Oligocene and initiation of a deformation front to the south where the Oriente Transform Wrench corridor is now located. Compressive structures were overprinted by widespread extensional structures (D3), mainly faults with southward-directed normal displacement in the Oligocene to early Miocene. During this period the plate boundary jumped to the Oriente fault. This event was followed by transpressive and transtensive structures (D4-D6) due to further development of the sinistral E-trending Oriente Transform wrench corridor. These structures are consistent with oblique convergence in a wide zone of left-lateral shear along an E-W-oriented transform fault

Quantum critical point and scaling in a layered array of ultrasmall Josephson junctions

We have studied a quantum Hamiltonian that models an array of ultrasmall Josephson junctions with short range Josephson couplings, $E_J$, and charging energies, $E_C$, due to the small capacitance of the junctions. We derive a new effective quantum spherical model for the array Hamiltonian. As an application we start by approximating the capacitance matrix by its self-capacitive limit and in the presence of an external uniform background of charges, $q_x$. In this limit we obtain the zero-temperature superconductor-insulator phase diagram, $E_J^{\rm crit}(E_C,q_x)$, that improves upon previous theoretical results that used a mean field theory approximation. Next we obtain a closed-form expression for the conductivity of a square array, and derive a universal scaling relation valid about the zero--temperature quantum critical point. In the latter regime the energy scale is determined by temperature and we establish universal scaling forms for the frequency dependence of the conductivity.Comment: 18 pages, four Postscript figures, REVTEX style, Physical Review B 1999. We have added one important reference to this version of the pape

Lattice QCD Simulations in External Background Fields

We discuss recent results and future prospects regarding the investigation, by lattice simulations, of the non-perturbative properties of QCD and of its phase diagram in presence of magnetic or chromomagnetic background fields. After a brief introduction to the formulation of lattice QCD in presence of external fields, we focus on studies regarding the effects of external fields on chiral symmetry breaking, on its restoration at finite temperature and on deconfinement. We conclude with a few comments regarding the effects of electromagnetic background fields on gluodynamics.Comment: 31 pages, 10 figures, minor changes and references added. To appear in Lect. Notes Phys. "Strongly interacting matter in magnetic fields" (Springer), edited by D. Kharzeev, K. Landsteiner, A. Schmitt, H.-U. Ye

GBA and APOE ε4 associate with sporadic dementia with Lewy bodies in European genome wide association study

Dementia with Lewy Bodies (DLB) is a common neurodegenerative disorder with poor prognosis and mainly unknown pathophysiology. Heritability estimates exceed 30% but few genetic risk variants have been identified. Here we investigated common genetic variants associated with DLB in a large European multisite sample. We performed a genome wide association study in Norwegian and European cohorts of 720 DLB cases and 6490 controls and included 19 top-associated single-nucleotide polymorphisms in an additional cohort of 108 DLB cases and 75545 controls from Iceland. Overall the study included 828 DLB cases and 82035 controls. Variants in the ASH1L/GBA (Chr1q22) and APOE ε4 (Chr19) loci were associated with DLB surpassing the genome-wide significance threshold (p < 5 × 10). One additional genetic locus previously linked to psychosis in Alzheimer's disease, ZFPM1 (Chr16q24.2), showed suggestive association with DLB at p-value < 1 × 10. We report two susceptibility loci for DLB at genome-wide significance, providing insight into etiological factors. These findings highlight the complex relationship between the genetic architecture of DLB and other neurodegenerative disorders

Consenso colombiano de atención, diagnóstico y manejo de la infección por SARS-COV-2/COVID-19 en establecimientos de atención de la salud Recomendaciones basadas en consenso de expertos e informadas en la evidencia

The “Asociación Colombiana de Infectología” (ACIN) and the “Instituto de Evaluación de Nuevas Tecnologías de la Salud” (IETS) created a task force to develop recommendations for Covid 19 health care diagnosis, management and treatment informed, and based, on evidence. Theses reccomendations are addressed to the health personnel on the Colombian context of health services. © 2020 Asociacion Colombiana de Infectologia. All rights reserved

In Vitro Identification of Novel Plasminogen-Binding Receptors of the Pathogen Leptospira interrogans

Background: Leptospirosis is a multisystem disease caused by pathogenic strains of the genus Leptospira. We have reported that Leptospira are able to bind plasminogen (PLG), to generate active plasmin in the presence of activator, and to degrade purified extracellular matrix fibronectin. Methodology/Principal Findings: We have now cloned, expressed and purified 14 leptospiral recombinant proteins. The proteins were confirmed to be surface exposed by immunofluorescence microscopy and were evaluated for their ability to bind plasminogen (PLG). We identified eight as PLG-binding proteins, including the major outer membrane protein LipL32, the previously published rLIC12730, rLIC10494, Lp29, Lp49, LipL40 and MPL36, and one novel leptospiral protein, rLIC12238. Bound PLG could be converted to plasmin by the addition of urokinase-type PLG activator (uPA), showing specific proteolytic activity, as assessed by its reaction with the chromogenic plasmin substrate, D-Val-Leu-Lys 4-nitroanilide dihydrochloride. The addition of the lysine analog 6-aminocaproic acid (ACA) inhibited the protein-PLG interaction, thus strongly suggesting the involvement of lysine residues in plasminogen binding. The binding of leptospiral surface proteins to PLG was specific, dose-dependent and saturable. PLG and collagen type IV competed with LipL32 protein for the same binding site, whereas separate binding sites were observed for plasma fibronectin. Conclusions/Significance: PLG-binding/activation through the proteins/receptors on the surface of Leptospira could help the bacteria to specifically overcome tissue barriers, facilitating its spread throughout the host.FAPESP (Fundacao de Amparo a Pesquisa do Estado de Sao Paulo)CNPq (Conselho Nacional de Desenvolvimento Cientifico e Tecnologico)Fundacao Butantan, BrazilFAPESP (Brazil

Global maps of soil temperature.

Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1-km &lt;sup&gt;2&lt;/sup&gt; resolution for 0-5 and 5-15 cm soil depth. These maps were created by calculating the difference (i.e. offset) between in situ soil temperature measurements, based on time series from over 1200 1-km &lt;sup&gt;2&lt;/sup&gt; pixels (summarized from 8519 unique temperature sensors) across all the world's major terrestrial biomes, and coarse-grained air temperature estimates from ERA5-Land (an atmospheric reanalysis by the European Centre for Medium-Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10°C (mean = 3.0 ± 2.1°C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6 ± 2.3°C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler (-0.7 ± 2.3°C). The observed substantial and biome-specific offsets emphasize that the projected impacts of climate and climate change on near-surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil-related bioclimatic variables provided here are an important step forward for any application in ecology and related disciplines. Nevertheless, we highlight the need to fill remaining geographic gaps by collecting more in situ measurements of microclimate conditions to further enhance the spatiotemporal resolution of global soil temperature products for ecological applications