On the correlation between residual stresses and displacements of the polycrystalline lattice: an experimental strategy

This work aims to propose a micro-indent method to evaluate the correlation between the relaxation of residual stresses and the shape changes of the polycrystalline lattice in specimens of a rolled plate of AA 6082-T6 aluminium alloy. Rolling strengthens the surface of the plate by introducing compressive residual stresses. Then, these stresses are relaxed by thermal distension. The method of micro-indents allowed measuring residual displacements with an error below ± 300 nm. The results obtained reveal that the rolling direction plays a vital role in terms of asymmetric expansion of the lattice. Furthermore, the lattice accumulates and restores elastic strain energy in the clockwise and anti-clockwise direction of rotation, alternatively. Finally, when the stress release process is finishing, the lattice adjusts the angle of rotation to approximate to the initial geometric shape.Fil: Diaz, Felipe Victor. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Tecnológica Nacional. Facultad Regional Rafaela; ArgentinaFil: Rosso, F. N.. Universidad Tecnológica Nacional. Facultad Regional Rafaela; ArgentinaFil: Walker, A. C.. Universidad Tecnológica Nacional. Facultad Regional Rafaela; ArgentinaFil: Guidobono, A.P.M.. Instituto Nacional de Tecnología Industrial. Centro Regional Rosario; Argentin

The ability of multimerized cyclophilin A to restrict retrovirus infection

AbstractIn owl monkeys, the typical retroviral restriction factor of primates, TRIM5α, is replaced by TRIMCyp. TRIMCyp consists of the TRIM5 RING, B-box 2 and coiled-coil domains, as well as the intervening linker regions, fused with cyclophilin A. TRIMCyp restricts infection of retroviruses, such as human immunodeficiency virus (HIV-1) and feline immunodeficiency virus (FIV), with capsids that can bind cyclophilin A. The TRIM5 coiled coil promotes the trimerization of TRIMCyp. Here we show that cyclophilin A that is oligomeric as a result of fusion with a heterologous multimer exhibits substantial antiretroviral activity. The addition of the TRIM5 RING, B-box 2 and Linker 2 to oligomeric cyclophilin A generated a protein with antiretroviral activity approaching that of wild-type TRIMCyp. Multimerization increased the binding of cyclophilin A to the HIV-1 capsid, promoting accelerated uncoating of the capsid and restriction of infection

Millimagnitude Photometry for Transiting Extrasolar Planetary Candidates IV: The Puzzle of the Extremely Red OGLE-TR-82 Primary Solved

We present precise new V, I, and K-band photometry for the planetary transit candidate star OGLE-TR-82. Good seeing V-band images acquired with VIMOS instrument at ESO VLT allowed us to measure V=20.6+-0.03 mag star in spite of the presence of a brighter neighbour about 1" away. This faint magnitude answers the question why it has not been possible to measure radial velocities for this object. One transit of this star has been observed with GMOS-S instrument of GEMINI-South telescope in i and g-bands. The measurement of the transit allows us to verify that this is not a false positive, to confirm the transit amplitude measured by OGLE, and to improve the ephemeris. The transit is well defined in i-band light curve, with a depth of A_i=0.034 mag. It is however, less well defined, but deeper (A_g=0.1 mag) in the g-band, in which the star is significantly fainter. The near-infrared photometry obtained with SofI array at the ESO-NTT yields K=12.2+-0.1 and V-K=8.4+-0.1, so red that it is unlike any other transit candidate studied before. Due to the extreme nature of this object, we have not yet been able to measure velocities for this star, but based on the new data we consider two different possible configurations:(1) a nearby M7V star, or (2) a blend with a very reddened distant red giant. The nearby M7V dwarf hypothesis would give a radius for the companion of R_p=0.3+-0.1 R_J, i.e. the size of Neptune. Quantitative analysis of near-IR spectroscopy finally shows that OGLE-TR-82 is a distant, reddened metal poor early K giant. This result is confirmed by direct comparison with stellar templates that gives the best match for a K3III star. Therefore, we discard the planetary nature of the companion. Based on all the new data, we conclude that this system is a main-sequence binary blended with a background red giant.Comment: 26 pages, 9 figures, ApJ accepte

Genome-wide DNA methylation pattern in visceral adipose tissue differentiates insulin-resistant from insulin-sensitive obese subject

Elucidating the potential mechanisms involved in the detrimental effect of excess body weight on insulin action is an important priority in counteracting obesity-associated diseases. The present study aimed to disentangle the epigenetic basis of insulin resistance by performing a genome-wide epigenetic analysis in visceral adipose tissue (VAT) from morbidly obese patients depending on the insulin sensitivity evaluated by the clamp technique. The global human methylome screening performed in VAT from 7 insulin-resistant (IR) and 5 insulin-sensitive (IS) morbidly obese patients (discovery cohort) analyzed using the Infinium HumanMethylation450 BeadChip array identified 982 CpG sites able to perfectly separate the IR and IS samples. The identified sites represented 538 unique genes, 10% of which were diabetes-associated genes. The current work identified novel IR-related genes epigenetically regulated in VAT, such as COL9A1, COL11A2, CD44, MUC4, ADAM2, IGF2BP1, GATA4, TET1, ZNF714, ADCY9, TBX5, and HDACM. The gene with the largest methylation fold-change and mapped by 5 differentially methylated CpG sites located in island/shore and promoter region was ZNF714. This gene presented lower methylation levels in IR than in IS patients in association with increased transcription levels, as further reflected in a validation cohort (n = 24; 11 IR and 13 IS). This study reveals, for the first time, a potential epigenetic regulation involved in the dysregulation of VAT that could predispose patients to insulin resistance and future type 2 diabetes in morbid obesity, providing a potential therapeutic target and biomarkers for counteracting this process

Estudio Integral sobre la Evaluación del Recurso Eólico en Entornos Urbanos. Estación Anemométrica Adaptable

Como consecuencia de un intenso proceso de trabajo, coordinado con Investigadores del CIEMAT (Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas), se pretende comunicar el estado del trabajo de Investigación relacionado con la Evaluación del Potencial Eólico en entornos urbanos, con vistas a la posible generación de energía eléctrica limpia

DNA methylation map in circulating leukocytes mirrors subcutaneous adipose tissue methylation pattern: a genome-wide analysis from non-obese and obese patients

The characterization of the epigenetic changes within the obesity-related adipose tissue will provide new insights to understand this metabolic disorder, but adipose tissue is not easy to sample in population-based studies. We aimed to evaluate the capacity of circulating leukocytes to reflect the adipose tissue-specific DNA methylation status of obesity susceptibility. DNA samples isolated from subcutaneous adipose tissue and circulating leukocytes were hybridized in the Infinium HumanMethylation 450 BeadChip. Data were compared between samples from obese (n = 45) and non-obese (n = 8-10) patients by Wilcoxon-rank test, unadjusted for cell type distributions. A global hypomethylation of the differentially methylated CpG sites (DMCpGs) was observed in the obese subcutaneous adipose tissue and leukocytes. The overlap analysis yielded a number of genes mapped by the common DMCpGs that were identified to reflect the obesity state in the leukocytes. Specifically, the methylation levels of FGFRL1, NCAPH2, PNKD and SMAD3 exhibited excellent and statistically significant efficiencies in the discrimination of obesity from non-obesity status (AUC > 0.80; p < 0.05) and a great correlation between both tissues. Therefore, the current study provided new and valuable DNA methylation biomarkers of obesity-related adipose tissue pathogenesis through peripheral blood analysis, an easily accessible and minimally invasive biological material instead of adipose tissue

Millimagnitude Photometry for Transiting Extrasolar Planetary Candidates: II. Transits of OGLE-TR-113-b in the Optical and Near-IR

We present precise V and Ks-band transit photometry for the planetary host star OGLE-TR-113. Using the Ks-band photometry, we confirm the dwarf nature of OGLE-TR-113, and obtain new estimates for its effective temperature, distance and reddening. We employ the V-band photometry to obtain planetary and orbit parameters from the transit fit, a= (0.0232 \pm 0.0038) AU, orbital period P= (1.4324752 \pm 0.0000015) days, i= 86.7 - 90, R_p= (1.09 \pm 0.09) R_J. These values are in excellent agreement with previous works. Assuming a mass M_p= (1.32 \pm 0.19) M_J for the planet we obtain its mean density \rho= (1.26 \pm 0.50) g cm^{-3}, also in agreement with previous works. The transit observed in the Ks-band has a larger scatter and we find its amplitude to be consistent with that in the V-band. In this way, we find an independent confirmation of the planetary nature of OGLE-TR-113b.Comment: 26 pages, 10 figures, 1 table. Accepted for publication in the Astrophysical Journa

Design, development and validation of a new laryngo-pharyngeal endoscopic esthesiometer and range-finder based on the assessment of air-pulse variability determinants

BACKGROUND: Laryngo-pharyngeal mechano-sensitivity (LPMS) is involved in dysphagia, sleep apnea, stroke, irritable larynx syndrome and cough hypersensitivity syndrome among other disorders. These conditions are associated with a wide range of airway reflex abnormalities. However, the current device for exploring LPMS is limited because it assesses only the laryngeal adductor reflex during fiber-optic endoscopic evaluations of swallowing and requires a high degree of expertise to obtain reliable results, introducing intrinsic expert variability and subjectivity. METHODS: We designed, developed and validated a new air-pulse laryngo-pharyngeal endoscopic esthesiometer with a built-in laser range-finder (LPEER) based on the evaluation and control of air-pulse variability determinants and on intrinsic observer variability and subjectivity determinants of the distance, angle and site of stimulus impact. The LPEER was designed to be capable of delivering precise and accurate stimuli with a wide range of intensities that can explore most laryngo-pharyngeal reflexes. RESULTS: We initially explored the potential factors affecting the reliability of LPMS tests and included these factors in a multiple linear regression model. The following factors significantly affected the precision and accuracy of the test (P < 0.001): the tube conducting the air-pulses, the supply pressure of the system, the duration of the air-pulses, and the distance and angle between the end of the tube conducting the air-pulses and the site of impact. To control all of these factors, an LPEER consisting of an air-pulse generator and an endoscopic laser range-finder was designed and manufactured. We assessed the precision and accuracy of the LPEER's stimulus and range-finder according to the coefficient of variation (CV) and by looking at the differences between the measured properties and the desired values, and we performed a pilot validation on ten human subjects. The air-pulses and range-finder exhibited good precision and accuracy (CV < 0.06), with differences between the desired and measured properties at <3 % and a range-finder measurement error of <1 mm. The tests in patients demonstrated obtainable and reproducible thresholds for the laryngeal adductor, cough and gag reflexes. CONCLUSIONS: The new LPEER was capable of delivering precise and accurate stimuli for exploring laryngo-pharyngeal reflexes

El complejo volcánico cerros Bravos, región de Maricunga, Chile: Geología, alteración hidrotermal y mineralización

El Complejo Volcánico Cerros Bravos (Oligoceno-Mioceno) es un conjunto de lavas y domos dacítico-andesíticos calcoalcalinos de gran extensión (450 km2) ubicado a unos 140 km al este de Copiapó, Chile, que integra la Franja de Maricunga, cadena volcánica neógena que representa un arco pluto-volcánico de margen continental. Los análisis radiométricos K-Ar señalan que el complejo volcánico Cerros Bravos estuvo activo entre los 26-18 Ma (Oligoceno-Mioceno inferior) en tanto que el complejo La Coipa registra actividad hasta el Mioceno medio (15 Ma), y desde allí hacia el sur los centros volcánicos presentan edades entre 16 y 6 Ma. El complejo hospeda la zona de alteración hidrotermal del Prospecto Esperanza, sistema epitermal del tipo sulfato-ácido con mineralización de oro y plata controlada estructuralmente y asociada a una intensa silicificación y argilización con calcolinita, alunita y jarosita, con edades radiométricas K-Ar entre 20-18 Ma. Los estudios isotópicos de Pb realizados en rocas y sulfuros de los depósitos de la Franja de Maricunga indican que las rocas ígneas del Oligoceno-Mioceno son una mezcla de manto subcortical máfico o material cortical y material cortical radiogénico. El Pb en los depósitos de metales preciosos de la franja es dominado por una fuente como las rocas ígneas huéspedes y, localmente, otras rocas huéspedes (sedimentarias triásicas) pueden haber contribuido con Pb durante la circulación hidrotermal en ambiente cercano a la superficie. La aplicación de las metodologías de la teledetección en imágenes Landsat TM en la zona de Maricunga demostró ser una herramienta eficaz para la exploración ya que permitió destacar perfectamente las zonas de alteración hidrotermal presentes en el área y la elaboración de mapas de alta confiabilidad a escala regional

Intracellular Bacteria Encode Inhibitory SNARE-Like Proteins

Pathogens use diverse molecular machines to penetrate host cells and manipulate intracellular vesicular trafficking. Viruses employ glycoproteins, functionally and structurally similar to the SNARE proteins, to induce eukaryotic membrane fusion. Intracellular pathogens, on the other hand, need to block fusion of their infectious phagosomes with various endocytic compartments to escape from the degradative pathway. The molecular details concerning the mechanisms underlying this process are lacking. Using both an in vitro liposome fusion assay and a cellular assay, we showed that SNARE-like bacterial proteins block membrane fusion in eukaryotic cells by directly inhibiting SNARE-mediated membrane fusion. More specifically, we showed that IncA and IcmG/DotF, two SNARE-like proteins respectively expressed by Chlamydia and Legionella, inhibit the endocytic SNARE machinery. Furthermore, we identified that the SNARE-like motif present in these bacterial proteins encodes the inhibitory function. This finding suggests that SNARE-like motifs are capable of specifically manipulating membrane fusion in a wide variety of biological environments. Ultimately, this motif may have been selected during evolution because it is an efficient structural motif for modifying eukaryotic membrane fusion and thus contribute to pathogen survival