Magmatic and geotectonic significance of Santa Elena Peninsula, Costa Rica

We present a new integrated interpretation of the geochemistry and geotectonic significance of the Santa Elena Peninsula, which is divided in three units: 1) an overthrust allocthonous unit of ultramafic and mafic rocks, the Santa Elena Nappe; 2) an autochthonous basaltic sedimentary suite, resting immediately below the overthrust, the Santa Rosa Accretionary Complex; and 3) Islas Murciélago pillow and massive basaltic flows. In the Santa Elena Nappe three petrological affinities have been recognized: 1) the ultramafic complex, that corresponds to depleted (MORB-like) mantle serpentinizated peridotites, with very low TiO2 and high Ni and Cr; 2) the pegmatitic gabbros, layered gabbros and plagiogranites and basaltic dikes with low TiO2 (0.89%). These mafic associations have geochemical signatures that suggest an island arc origin and petrographic evidences of low grade metamorphism and hydrothermal alteration. The Santa Rosa Accretionary Complex includes pelagic and volcanoclastic sediments, tuffs and alkaline magmatic rocks, originated by low degree melting of enrichment OIB mantle source, and probably related with seamount portions incorporated into the accretionary prism. Islas Murciélago pillow and massive basalts show no clear structural relationship with the rest of the units, but are geochemically similar to the dolerites of the Santa Elena Nappe. Sr, Nd, and Pb isotopic ratios of the Santa Elena Nappe and the Santa Elena Accretionary Complex samples do not correspond to the Galapagos Mantle array, and have different mantle reservoirs and geochemical characteristics than the Nicoya Complex

OWA fuzzy regression

In this paper, the Ordered Weighted Averaging (OWA) operators will be considered to propose general fuzzy regression modeling technique for crisp/fuzzy-input fuzzy-output data. Here, by considering various kinds of a special form of OWA operators we will be able to 1. investigate different approaches for aggregation of residuals/errors, 2. construct a multi-objective optimization problem, 3. provide high-breakdown estimators, 4. identify poorly fitted data points, which might be considered as outliers while limiting their effects on the model, 5. show how robust alternatives to other fuzzy regression models can be obtained as a result. Finally, a special case of the OWA-based fuzzy regression model known as OWA-Least Trimmed Absolutes Deviations (OWA-LTAD) fuzzy regression model is studied in details for crisp-input fuzzy-output data. An algorithm is investigated in the present study for estimation process in which 1. the highest breakdown value will always be achieved (up to the maximum of 0.5) for problems with multiple outliers, 2. the poorly fitted dataset can be labeled as outliers in an elemental set. In the presence of multiple outliers, the new method is particularly useful, and the performance of the proposed approach is illustrated for modeling several simulated datasets and a real valued dataset all contaminated with multiple outliers as well. We will look at an application of the proposed approach, in particular, to detect outliers in such models. (c) 2021 Elsevier Inc. All rights reserved

Fuzzy regression analysis based on M-estimates

The least-squares technique has been shown to possess valuable properties as a method of the parameter estimation of classic and fuzzy regression analysis. However, the behavior and properties of the least-squares estimators are affected when outliers arise in the sample and/or by slight changes in the dataset. Robust techniques, on the other hand, provide robust estimators of the parameters which avoid such adverse effects. For this purpose, this paper extends the M-estimation approach to fuzzy regression analysis which provides consistent results in the presence of outliers. The parameters estimation problem is reduced to a reweighted algorithm which is a simple approach both theoretically and computationally. The proposed algorithm decreases the effect of outliers on the model fit by down-weighting them. To show the performances of the proposed method against some commonly used fuzzy regression models simulation studies, and two applicative examples based on real-world datasets in hydrology and atmospheric environment are provided. The sensitivity analysis of the estimated parameters are also reported based on a Monte-Carlo simulation study showing the efficiency of the proposed estimators in comparison with some other well-known methods in fuzzy regression analysis

Efectos de forma y tamaño del poro sobre las propiedades mecánicas de las membranas del grafeno nanoporoso

In this work, effects of shape and size of the pores on the mechanical properties of nanoporous graphene (NPG) membranes are studied. Molecular dynamics simulations were performed to study the mechanical and structural responses under uniaxial traction. The results of the stress-strain curves of NPG membranes show an elastic linear behavior for small strain (&lt;0.03) independent of the chiral direction. The chiral anisotropy (armchair and zigzag direction) is notable as deformation increases to the point of fracture. The NPG membranes with hexagonal and rectangular pores present a higher fracture stress (65 GPa and 81 GPa, respectively). Furthermore, Young's elastic modulus decreases as pore size increases (porosity). This study is expected to provide practical application as high performance membrane filters.En el presente trabajo se estudiaron los efectos de forma y tamaño de los poros sobre las propiedades mecánicas de membranas de grafeno nanoporosas (GNP). Las simulaciones de dinámica molecular fueron ejecutadas para estudiar las respuestas mecánicas y estructurales bajo una tracción uniaxial. Los resultados de las curvas tensión-deformación de las membranas de GNP muestran un comportamiento lineal elástico para razones de deformación pequeñas (<0.03) independiente de la dirección quiral. La anisotropía quiral (dirección armchair y zigzag) es notoria conforme se incrementa la deformación hasta el punto de fractura. Las membranas de GNP con poro hexagonal y rectangular presentan una mayor tensión de fractura (65 GPa y 81 GPa, respectivamente). Además, el módulo elástico de Young disminuye conforme se incrementa el tamaño del poro. Se espera que este estudio brinde aplicación práctica como filtros de membranas de alto rendimiento

Bidirectional counter-regulation of human lung mast cell and airway smooth muscle beta2-adrenoceptors

Human lung mast cells (HLMCs) play a central role in asthma pathogenesis through their relocation to the airway smooth muscle (ASM) bundles. β2 adrenoceptor (β2-AR)-agonists are used to relieve bronchoconstriction in asthma, but may reduce asthma control, particularly when used as monotherapy. We hypothesized that HLMC and human ASM cell (HASMC) responsiveness to β2-AR agonists would be attenuated when HLMCs are in contact with HASMCs. Cells were cultured in the presence of the short-acting β2-agonist albuterol, and the long-acting β2-agonists formoterol and olodaterol. Constitutive and FcεRI-dependent HLMC histamine release, HASMC contraction, and β2-AR phosphorylation at Tyr(350) were assessed. Constitutive HLMC histamine release was increased in HLMC-HASMC coculture and this was enhanced by β2-AR agonists. Inhibition of FcεRI-dependent HLMC mediator release by β2-agonists was greatly reduced in HLMC-HASMC coculture. These effects were reversed by neutralization of stem cell factor (SCF) or cell adhesion molecule 1 (CADM1). β2-AR agonists did not prevent HASMC contraction when HLMCs were present, but this was reversed by fluticasone. β2-AR phosphorylation at Tyr(350) occurred within 5 min in both HLMCs and HASMCs when the cells were cocultured, and was inhibited by neutralizing SCF or CADM1. HLMC interactions with HASMCs via CADM1 and Kit inhibit the potentially beneficial effects of β2-AR agonists on these cells via phosphorylation of the β2-AR. These results may explain the potentially adverse effects of β2-ARs agonists when used for asthma therapy. Targeting SCF and CADM1 may enhance β2-AR efficacy, particularly in corticosteroid-resistant patients

Propiedades estructuralesy magnéticas de aleaciones cristalinas desordenadas Fe50Mn25+xSn25-x con x: -1.25, 0.0, 2.5, 5.0, 7.5

Disordered crystalline Fe50Mn25+xSn25-x alloys, with x = -1.25, 0.0, 2.5, 5.0, 7.5 (close to the full-Heusler alloys), were arc-melted in a high purity argon atmosphere and the molten pellets were individually sealed in quartz tubes also under argon atmosphere. Subsequently, they were annealed at 1173 K for 4 days, being finally quenched in a bath with cold water. Structural and magnetic properties have systematically been studied using X-ray diffraction, 57Fe, and 119Sn Mössbauer spectroscopies, and magnetization measurements recorded at room temperature. Rietveld refinement of the X-ray diffraction patterns of the annealed samples with x = -1.25 and 0 has revealed the presence of two hexagonal crystallographic phases: (i) a chemically disordered solid solution identified as  e-(Fe/Mn)3Sn (majority fraction) and (ii) the e-Fe5Sn3 intermetallic compound (minority fraction). For samples with x = 2.5, 5.0, and 7.5, the Rietveld analysis has only indicated the presence of a chemically disordered solid solution identified as e-(Fe/Mn)3(Sn/Fe/Mn). Although compositions of the Fe50Mn25+xSn25-x alloys are close to that of full-Heusler alloys, none of them has the expected L21 structure. The average crystallite sizes, estimated from the Williamson-Hall method, are in the range of 256-62 nm. The average sizes has gradually decreased as the x-content is increased. Mössbauer results have shown localized-type magnetism from Fe non-equivalent sites, and itinerant-like magnetism on 119Sn-probes. Magnetic hysteresis loops, recorded at 300 K for a maximum field of 2200 Oe, have indicated that the remanent and coercive fields have systematically decreased as the x-parameter has increased. Coercive fields are in the range for soft magnets (1-20 Oe).Aleaciones cristalinas desordenadas Fe50Mn25+xSn25-x, con x = -1.25, 0.0, 2.5, 5.0, 7.5, cercanas a las composiciones de Heusler-211, fueron preparadas por fusión en atmósfera inerte, subsecuentemente, sometidas a recocido térmico durante 4 días a 1173 K y, finalmente, enfriadas en agua helada. Todas las aleaciones han sido sistemáticamente analizadas mediante difracción de rayos X, espectroscopias Mössbauer de 57Fe y 119Sn, y medidas de magnetización a temperatura ambiente. Los análisis Rietveld de los difractogramas de las muestras con x = -1.25 y 0.0 muestran la presencia de dos fases cristalográficas hexagonales: (i) la solución sólida químicamente desordenada e-(Fe/Mn)3Sn (mayoritaria), y (ii) el intermetálico e-Fe5Sn3 (minoritaria); mientras que, las aleaciones con x = 2.5, 5.0 y 7.5, presentan solo la solución sólida desordenada, e-(Fe/Mn)3(Sn/Fe/Mn). Si bien, las composiciones de las aleaciones Fe50Mn25+xSn25-x son cercanas a las de Heusler-211, ninguna tiene la estructura cúbica L21 característica de estas. Los tamaños medios de los cristalitos, calculados por el método de Williamson-Hall, están dentro del rango 256-62 nm y disminuyen cuando x aumenta. Los resultados Mössbauer de todas las aleaciones muestran la característica de magnetismo localizado a través de la distribución de campos magnéticos hiperfinos en los sitios de Fe, y de magnetismo itinerante a través de los campos transferidos desde los átomos de Fe en los núcleos de 119Sn. Los campos coercitivos y remanentes, obtenidos por medidas de magnetización bajo campo magnético aplicado entre -2200 y +2200 Oe, disminuyen cuando x aumenta. Los valores de los campos coercitivos están en el rango de los magnetos blandos (1-20 Oe)

Protein phosphatase 5 mediates corticosteroid insensitivity in airway smooth muscle in patients with severe asthma.

BACKGROUND: The mechanisms driving glucocorticoid (GC) insensitivity in patients with severe asthma are still unknown. Recent evidence suggests the existence of GC-insensitive pathways in airway smooth muscle (ASM) caused by a defect in GC receptor (GRα) function. We examined whether other mechanisms could potentially explain the reduced sensitivity of ASM cells to GC in severe asthmatics. METHODS: Airway smooth muscle cells from healthy and severe asthmatic subjects were treated with TNF-α and responses to corticosteroids in both cohorts were compared by ELISA, immunoblot, immunohistochemistry and real-time PCR. Immunohistochemistry and flow cytometry assays were used to assess the expression of the protein phosphatase PP5 in endobronchial biopsies and ASM cells. RESULTS: The production of CCL11 and CCL5 by TNF-α was insensitive to both fluticasone and dexamethasone in ASM cells from severe asthmatic compared to that in healthy subjects. Fluticasone-induced GRα nuclear translocation, phosphorylation at serine 211 and expression of GC-induced leucine zipper (GILZ) were significantly reduced in ASM cells from severe asthmatics compared to responses in healthy subjects. Levels of PP5 were increased in ASM cells from severe asthmatics and PP5 knockdown using siRNA restored fluticasone repressive action on chemokine production and its ability to induce GRα nuclear translocation and GRE-dependent GILZ expression. In vivo PP5 expression was also increased in the ASM bundles in endobronchial biopsies in severe asthmatics. CONCLUSIONS: PP5-dependent impairment of GRα function represents a novel mechanism driving GC insensitivity in ASM in severe asthma

Validation of antibodies for the specific detection of human TRPA1

The transient receptor potential cation channel family member ankyrin 1 (TRPA1) is a potential target for several diseases, but detection of human TRPA1 (hTRPA1) protein in cells and tissues is problematic as rigorous antibody validation is lacking. We expressed hTRPA1 in a TRPA1-negative cell line to evaluate 5 commercially available antibodies by western blotting, immunofluorescence, immunocytochemistry and flow cytometry. The three most cited anti-TRPA1 antibodies lacked sensitivity and/or specificity, but two mouse monoclonal anti-TRPA1 antibodies detected hTRPA1 specifically in the above assays. This enabled the development of a flow cytometry assay, which demonstrated strong expression of TRPA1 in human lung myofibroblasts, human airway smooth muscle cells but not lung mast cells. The most cited anti-TRPA1 antibodies lack sensitivity and/or specificity for hTRPA1. We have identified two anti-TRPA1 antibodies which detect hTRPA1 specifically. Previously published data regarding human TRPA1 protein expression may need revisiting