186 research outputs found

    Intermolecular forces at ice and water interfaces: premelting, surface freezing and regelation

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    Using Lifshitz theory we assess the role of van der Waals forces at interfaces of ice and water. The results are combined with measured structural forces from computer simulations to develop a quantitative model of the surface free energy of premelting films. This input is employed within the framework of wetting theory and allows us to predict qualitatively the behavior of quasi-liquid layer thickness as a function of ambient conditions. Our results emphasize the significance of vapor pressure. The ice vapor interface is shown to exhibit only incomplete premelting, but the situation can shift to a state of complete surface melting above water saturation. The results obtained serve also to assess the role of subsurface freezing at the water-vapor interface, and we show that intermolecular forces favor subsurface ice nucleation only in conditions of water undersaturation. We show ice regelation at ambient pressure may be explained as a process of capillary freezing, without the need to invoke the action of bulk pressure melting. Our results for van der Waals forces are exploited in order to gauge dispersion interactions in empirical point charge models of water

    A Highly Conductive All-Carbon Linked 3D Covalent Organic Framework Film

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    Here an all-carbon linked 3D covalent organic framework (COF) is introduced by employing a templated surface reaction in a continuous flow (TSRCF). The presented method of synthesis provides spatial control over the reaction chemistry and allows for the creation of ultrasmooth COF films of desired thickness and significant crystallinity. The films show high electrical conductivity (≈3.4 S m−1) after being doped with tetracyanoquinodimethane (TCNQ), setting a new record for 3D COF materials. The concurrence of 3D nanosized channels and high conductivity opens up for a number of hitherto unexplored applications for this class of materials, such as high surface area electrodes, electrochemical transistors, and for electronic sensing

    Adherence to healthy lifestyle habits is a determinant of the effectiveness of weight loss among patients undergoing endoscopic bariatric therapies

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    Endoscopic bariatric therapies (EBTs) are promising strategies for the treatment of obesity. However, there is still great variability in its effectiveness in weight loss. Thus, we investigated whether adherence to healthy lifestyle habits is a significant determinant of weight loss effectiveness among patients undergoing EBTs. Additionally, the role of eating behaviors and psychological traits in the effectiveness of weight loss was studied. A cohort of 361 participants (81.4% women; age 41.8 ± 9.5 years; BMI 37.8 ± 4.3 kg/m2) was followed for 1 year after EBT. Anthropometric parameters, adherence to healthy lifestyle habits, emotional eating, and psychological traits (anxiety and depression) were evaluated. General linear models were used to compare outcome variables according to weight loss effectiveness groups (poor vs. good weight-loss-responders). Additionally, a hierarchical linear regression model was used to determine whether adherence to healthy lifestyle habits, emotional eating, or psychological traits were significant predictors of excess weight loss (%EWL). One year after EBT, weight loss differed significantly between good and poor weight-loss-responders (67.5% EWL [95% CI: 64.2, 70.8] vs. 28.2% EWL [95% CI: 25.5, 30.9], p 2 times/week were the two lifestyle habits that most significantly determined weight loss response. Furthermore, our results revealed that while adherence to healthy lifestyle habits was a significant determinant of %EWL 3, 6, and 12 months after EBT (p < 0.001), emotional eating was a significant determinant of %EWL only 3 and 6 months after the intervention (p < 0.01 and p < 0.05, respectively). Regarding psychological traits, we observed that neither anxiety nor depression were significant determinants of %EWL. Our results revealed that adherence to healthy lifestyle habits is a significant determinant for weight loss effectiveness among patients with obesity undergoing EBT. These findings highlight the importance of implementing an adequate nutritional intervention program, especially since patients who adhere to good lifestyle habits are able to achieve a weight loss that would be comparable with bariatric surgery

    High-Pressure and High-Temperature Chemistry of Phosphorus and Nitrogen: Synthesis and Characterization of α- and γ-P3N5

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    The direct chemical reactivity between phosphorus and nitrogen was induced under high-pressure and high-temperature conditions (9.1 GPa and 2000-2500 K), generated by a laser-heated diamond anvil cell and studied by synchrotron X-ray diffraction, Raman spectroscopy, and DFT calculations. alpha-P3N5 and gamma-P3N5 were identified as reaction products. The structural parameters and vibrational frequencies of gamma-P3N5 were characterized as a function of pressure during room-temperature compression and decompression to ambient conditions, determining the equation of state of the material up to 32.6 GPa and providing insight about the lattice dynamics of the unit cell during compression, which essentially proceeds through the rotation of the PN5 square pyramids and the distortion of the PN4 tetrahedra. Although the identification of alpha-P3N5 demonstrates for the first time the direct synthesis of this compound from the elements, its detection in the outer regions of the laser-heated area suggests alpha-P3N5 as an intermediate step in the progressive nitridation of phosphorus toward the formation of gamma-P3N5 with increasing coordination number of P by N from 4 to 5. No evidence of a higher-pressure phase transition was observed, excluding the existence of predicted structures containing octahedrally hexacoordinated P atoms in the investigated pressure range

    Libros.

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    J. Lázaro y F. Bujosa. Historiografía de la psiquiatría española. Editorial Triacastela, 2000. 194 páginas. Antonio Sánchez-Barranco Ruiz López Barberá E. y Población P. Introducción al Role-Playing Pedagógico, Bilbao, Desclée De Brouwer, 2000. José Antonio Espina Barrio Alberto Fernández Liria y Beatriz Rodríguez Vega. La práctica de la psicoterapia. La construcción de narrativas terapéuticas. Desclée Brouwet: 2001. 364 páginas. Fernando Mansilla Enrique Rivas. Psiquiatría-Psicoanálisis. La clínica de la sospecha. Miguel Gómez Ediciones. 2000. 283 páginas. Fernando Mansilla. British Medical Joumal. del 2 de diciembre de 2000, Onésimo González Alvare

    Libros.

    Get PDF
    J. Lázaro y F. Bujosa. Historiografía de la psiquiatría española. Editorial Triacastela, 2000. 194 páginas. Antonio Sánchez-Barranco Ruiz López Barberá E. y Población P. Introducción al Role-Playing Pedagógico, Bilbao, Desclée De Brouwer, 2000. José Antonio Espina Barrio Alberto Fernández Liria y Beatriz Rodríguez Vega. La práctica de la psicoterapia. La construcción de narrativas terapéuticas. Desclée Brouwet: 2001. 364 páginas. Fernando Mansilla Enrique Rivas. Psiquiatría-Psicoanálisis. La clínica de la sospecha. Miguel Gómez Ediciones. 2000. 283 páginas. Fernando Mansilla. British Medical Joumal. del 2 de diciembre de 2000, Onésimo González Alvare

    Incidence of new HIV diagnoses in Spain, 2004-2009.

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    [ES] Objetivo Describir la incidencia de nuevos diagnósticos de infección por el virus de la inmunodeficiencia humana (VIH) y su tendencia. Métodos Se incluyeron los nuevos diagnósticos de VIH notificados en 2009 en las 15 comunidades autónomas con sistemas de información (64% de la población española). Para analizar las tendencias durante 2004-2009 se incluyeron las nueve comunidades con datos en ese periodo. Se obtuvo información clínico-epidemiológica de las hojas de notificación de casos y se realizaron distribuciones de nuevos diagnósticos y diagnóstico tardío según distintas variables. Para evaluar las tendencias se ajustó un modelo de Poisson. Resultados En 2009 se notificaron 2.264 nuevos diagnósticos de VIH, la mayoría en hombres (80%). La mediana de edad al diagnóstico fue de 36 años (rango intercuartílico 29-43) y el 37,6% de los casos eran inmigrantes, destacando los latinoamericanos y los subsaharianos. La categoría de transmisión más común (42,5%) fue la de hombres que tienen sexo con hombres, seguida de la heterosexual (34,5%) y la parenteral (8,1%). Al diagnóstico, la mediana de CD4/μl era de 347 (rango intercuartílico: 152-555) y un 50,2% tenían <350. La tasa media de incidencia de nuevos diagnósticos entre 2004 y 2009 fue de 91,14 por millón de habitantes; se observó una tendencia creciente de las tasas entre los hombres que tienen sexo con hombres, y decreciente de la transmisión parenteral. Conclusiones La epidemiología del VIH en España ha cambiado mucho respecto a los años 1990. Actualmente predomina la transmisión sexual, sobre todo entre los hombres que tienen sexo con hombres, y los inmigrantes son parte importante de la epidemia. En 2004-2009, la tendencia es heterogénea en las tres categorías de transmisión más relevantes. [EN] To describe the incidence of new HIV diagnoses and its trend in Spain. All new HIV diagnoses notified to the case-registries of 15 autonomous regions (64% of the total Spanish population) in 2009 were analyzed. To evaluate trends from 2004 to 2009, data from only nine regions were available. Clinical-epidemiological data were obtained from the notification forms. Distributions of new HIV diagnoses and late diagnoses according to several variables were performed. The Poisson distribution was used to evaluate trends. In 2009, 2264 new HIV diagnoses were notified, mostly in men (80%). The median age at diagnosis was 36 years (interquartile range 29-43) and 37.6% of affected individuals were immigrants, mostly from Latin-America and sub-Saharan Africa. The most common transmission category (42.5%) was men who have sex with men (MSM) followed by the heterosexual and parenteral modes of transmission (34.5% and 8.1%, respectively). The median CD4 count at diagnosis was 347 (interquartile range: 152-555), and CD4 count was <350 in 50.2% of patients. From 2004 to 2009, the mean incidence rate of new HIV diagnoses was 91.14 per million inhabitants; an increasing trend for rates in MSM, as well as a decreasing trend for the parenteral mode of transmission, were observed. In Spain, the epidemiology of HIV infection has changed since the mid-1990s. Currently, the most frequent transmission category is sexual transmission, particularly among MSM, and immigrants are an important part of the epidemic. Heterogeneous trends for the three main transmission categories were observed from 2004 to 2009.S

    Regulation of SCF TIR1/AFB E3 ligase assembly by S-nitrosylation of Arabidopsis SKP1-like1 impacts on auxin signaling

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    The F-box proteins (FBPs) TIR1/AFBs are the substrate recognition subunits of SKP1–cullin–F-box (SCF) ubiquitin ligase complexes and together with Aux/IAAs form the auxin co-receptor. Although tremendous knowledge on auxin perception and signaling has been gained in the last years, SCFTIR1/AFBs complex assembly and stabilization are emerging as new layers of regulation. Here, we investigated how nitric oxide (NO), through S-nitrosylation of ASK1 is involved in SCFTIR1/AFBs assembly. We demonstrate that ASK1 is S-nitrosylated and S-glutathionylated in cysteine (Cys) 37 and Cys118 residues in vitro. Both, in vitro and in vivo protein-protein interaction assays show that NO enhances ASK1 binding to CUL1 and TIR1/AFB2, required for SCFTIR1/AFB2 assembly. In addition, we demonstrate that Cys37 and Cys118 are essential residues for proper activation of auxin signaling pathway in planta. Phylogenetic analysis revealed that Cys37 residue is only conserved in SKP proteins in Angiosperms, suggesting that S-nitrosylation on Cys37 could represent an evolutionary adaption for SKP1 function in flowering plants. Collectively, these findings indicate that multiple events of redox modifications might be part of a fine-tuning regulation of SCFTIR1/AFBs for proper auxin signal transduction.This work has been supported by grants from CONICET (PIP 0202 to M.C.T), Universidad Nacional de Mar del Plata and Agencia Nacional de Promoción Científica y Tecnológica, -Argentina (PICT 1167 to M.C.T and PICT 2421 to C.A.C); from the Spanish Government (PS09/00101 and PI12/00875 to A.M.R., cofinanced by the European Union ERDF), and by the Argentinian-Spanish Integrated Action ES/11/02 / PRIAIBAR- 2011-0782. A.M.R. is supported by the I3SNS programme (ISCIII, Spanish Government). The Proteomics Service of the CBMSO is a member of Proteored (PRB2-ISCIII), and is supported by grants PT13/ 0001/0024 and PT17/0019/0018 of Spanish Government (cofinanced by the European Union ERDF). Work in the laboratory of M.E is supported by grants from the National Institutes of Health (NIH) GM43644, The Howard Hughes Medical Institute and the Gordon and Betty Moore Foundation, US
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