Superfluidity vs Bose-Einstein condensation in a Bose gas with disorder

We investigate the phenomenon of Bose-Einstein condensation and superfluidity in a Bose gas at zero temperature with disorder. By using the Diffusion Monte-Carlo method we calculate the superfluid and the condensate fraction of the system as a function of density and strength of disorder. In the regime of weak disorder we find agreement with the analytical results obtained within the Bogoliubov model. For strong disorder the system enters an unusual regime where the superfluid fraction is smaller than the condensate fraction.Comment: 4 pages, 4 Postscript figure

A reciclable bifuctional acid-base organocatalyst with ionic liquid character. The role of sites separation and spatial configuration on different condensation reaction

A series of bifunctional organic catalysts containing acid and basic sites with ionic liquid characteristics have been prepared and their catalytic activity and reaction coordinate for aldol and Knoevenagel condensations have been compared. While the only factor controlling catalyst activity for the Knoevenagel condensation was the distance between the acid and base sites, the spatial orientation of the organocatalyst is also key to achieve high activity and selectivity in the Claisen-Schmidt condensation. Mechanistic studies based on theoretical DFT calculations show that the acid-base bifunctional organocatalyst follows a mechanism inspired in natural aldolases for the synthesis of trans-chalcones, being able to produce a large variety of these compounds of industrial interest. The combination of the acid-base pairs within the proper geometry and the ionic liquid nature makes this catalyst active, selective and recyclable.We thank Consolider-Ingenio 2010 (project MULTICAT), Spanish MICINN (Project MAT2006-14274-C02-01), Generalitat Valenciana (Project PROMETEO/2008/130), and Fundacion Areces for financial support.Corma Canós, A.; Boronat Zaragoza, M.; Climent Olmedo, MJ.; Iborra Chornet, S.; Montón Molina, R.; Sabater Picot, MJ. (2011). A reciclable bifuctional acid-base organocatalyst with ionic liquid character. The role of sites separation and spatial configuration on different condensation reaction. Physical Chemistry Chemical Physics. 13(38):17255-17261. https://doi.org/10.1039/c1cp21986cS17255172611338Motokura, K., Tada, M., & Iwasawa, Y. (2008). Acid-Base Bifunctional Catalytic Surfaces for Nucleophilic Addition Reactions. Chemistry - An Asian Journal, 3(8-9), 1230-1236. doi:10.1002/asia.200800126Gröger, H. (2001). 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Towards Perfect Catalytic Asymmetric Synthesis: Dual Activation of the Electrophile and the Nucleophile. Angewandte Chemie International Edition, 43(35), 4566-4583. doi:10.1002/anie.200300635Wang, Y., Li, H., Wang, Y.-Q., Liu, Y., Foxman, B. M., & Deng, L. (2007). Asymmetric Diels−Alder Reactions of 2-Pyrones with a Bifunctional Organic Catalyst. Journal of the American Chemical Society, 129(20), 6364-6365. doi:10.1021/ja070859hLin, Y.-M., Boucau, J., Li, Z., Casarotto, V., Lin, J., Nguyen, A. N., & Ehrmantraut, J. (2007). A Lewis Acid−Lewis Base Bifunctional Catalyst from a New Mixed Ligand. Organic Letters, 9(4), 567-570. doi:10.1021/ol0626903Corma, A., Ródenas, T., & Sabater, M. (2010). A Bifunctional Pd/MgO Solid Catalyst for the One-Pot Selective N-Monoalkylation of Amines with Alcohols. Chemistry - A European Journal, 16(1), 254-260. doi:10.1002/chem.200901501Ruiz, V. R., Corma, A., & Sabater, M. J. (2010). New route for the synthesis of benzimidazoles by a one-pot multistep process with mono and bifunctional solid catalysts. Tetrahedron, 66(3), 730-735. doi:10.1016/j.tet.2009.11.048Boronat, M., Climent, M. J., Corma, A., Iborra, S., Montón, R., & Sabater, M. J. (2010). Bifunctional Acid-Base Ionic Liquid Organocatalysts with a Controlled Distance Between Acid and Base Sites. Chemistry - A European Journal, 16(4), 1221-1231. doi:10.1002/chem.200901519Boronat, M., Concepción, P., Corma, A., Navarro, M. T., Renz, M., & Valencia, S. (2009). Reactivity in the confined spaces of zeolites: the interplay between spectroscopy and theory to develop structure–activity relationships for catalysis. Physical Chemistry Chemical Physics, 11(16), 2876. doi:10.1039/b821297jCorma, A., & Renz, M. (2007). A General Method for the Preparation of Ethers Using Water-Resistant Solid Lewis Acids. Angewandte Chemie International Edition, 46(1-2), 298-300. doi:10.1002/anie.200604018Boronat, M., Corma, A., Renz, M., & Viruela, P. M. (2006). Predicting the Activity of Single Isolated Lewis Acid Sites in Solid Catalysts. Chemistry - A European Journal, 12(27), 7067-7077. doi:10.1002/chem.200600478Climent, M. J., Corma, A., De Frutos, P., Iborra, S., Noy, M., Velty, A., & Concepción, P. (2010). Chemicals from biomass: Synthesis of glycerol carbonate by transesterification and carbonylation with urea with hydrotalcite catalysts. The role of acid–base pairs. Journal of Catalysis, 269(1), 140-149. doi:10.1016/j.jcat.2009.11.001Climent, M. J., Corma, A., Iborra, S., Mifsud, M., & Velty, A. (2010). New one-pot multistep process with multifunctional catalysts: decreasing the E factor in the synthesis of fine chemicals. Green Chem., 12(1), 99-107. doi:10.1039/b919660aCorma, A., Iborra, S., & Velty, A. (2007). Chemical Routes for the Transformation of Biomass into Chemicals. Chemical Reviews, 107(6), 2411-2502. doi:10.1021/cr050989dCliment, M. J., Corma, A., & Iborra, S. (2011). Heterogeneous Catalysts for the One-Pot Synthesis of Chemicals and Fine Chemicals. Chemical Reviews, 111(2), 1072-1133. doi:10.1021/cr1002084Koshland, D. E. (1958). Application of a Theory of Enzyme Specificity to Protein Synthesis. Proceedings of the National Academy of Sciences, 44(2), 98-104. doi:10.1073/pnas.44.2.98Bass, J. D., Solovyov, A., Pascall, A. J., & Katz, A. (2006). Acid−Base Bifunctional and Dielectric Outer-Sphere Effects in Heterogeneous Catalysis:  A Comparative Investigation of Model Primary Amine Catalysts. Journal of the American Chemical Society, 128(11), 3737-3747. doi:10.1021/ja057395cVasella, A., Davies, G. J., & Böhm, M. (2002). Glycosidase mechanisms. Current Opinion in Chemical Biology, 6(5), 619-629. doi:10.1016/s1367-5931(02)00380-0Drexler, M. (2003). The effect of solvents on the heterogeneous synthesis of flavanone over MgO. Journal of Catalysis, 214(1), 136-145. doi:10.1016/s0021-9517(02)00013-1Fuentes, A., Marinas, J. M., & Sinisterra, J. V. (1987). Catalyzed synthesis of chalcones under interfacial solid-liquid conditions with ultrasound. Tetrahedron Letters, 28(39), 4541-4544. doi:10.1016/s0040-4039(00)96558-4Climent, M. ., Corma, A., Iborra, S., & Velty, A. (2004). Activated hydrotalcites as catalysts for the synthesis of chalcones of pharmaceutical interest. Journal of Catalysis, 221(2), 474-482. doi:10.1016/j.jcat.2003.09.012Shen, J., Wang, H., Liu, H., Sun, Y., & Liu, Z. (2008). Brønsted acidic ionic liquids as dual catalyst and solvent for environmentally friendly synthesis of chalcone. Journal of Molecular Catalysis A: Chemical, 280(1-2), 24-28. doi:10.1016/j.molcata.2007.10.021Ballesteros, J. F., Sanz, M. J., Ubeda, A., Miranda, M. A., Iborra, S., Paya, M., & Alcaraz, M. J. (1995). 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The use of wet-laid techniques to obtain flax nonwovens with different thermoplastic binding fibers for technical insulation applications

[EN] In this work, the wet-laid technique has been used to obtain flax nonwovens thermally bonded with different contents of polyvinyl alcohol (PVA) and bicomponent polyamide 6/copolyamide (PA6/CoPA) fibers in the 10-30 wt.% range. Scanning electron microscopy has been used to evaluate the formation of interlock points through melted polymer and flax fibers. Volume porosity has been estimated through determination of thickness and surface mass. Tensile strength and elongation at break have been determined on longitudinal (preferential) and transversal directions to evaluate anisotropy. The sound absorption properties of stacked sheets of flax: PVA and flax: PA6/CoPA nonwovens have been evaluated. In addition, the thermal insulating properties of individual nonwovens have been obtained. Mechanical characterization shows slight anisotropy. The absorption coefficient is interesting in the medium frequencies range, and relatively low thermal conductivity and thermal resistance values are obtained with these nonwovens (in the 0.020-0.025Wm(-1) K-1 range for flax: PVA nonwovens and in the 0.09-0.10Wm(-1) K-1 range for flax: PA6/CoPA nonwovens). By taking into account these features, these nonwoven substrates could find interesting applications as sound absorbers and/or thermal insulation materials in technical applications.This work is part of the project IPT-310000-2010-037, "ECOTEXCOMP: Research and development of textile structures useful as reinforcement of composite materials with marked ecological character", and was supported by the "Ministerio de Ciencia e Innovacion", with a grant of (sic)189,540.20, within the Plan Nacional de Investigacion Cientifica, Desarrollo e Innovacion Tecnologica 2008-2011 and funded by the European Union through FEDER funds, Technology Fund 2007-2013 and Operational Programme on R + D + i for and on behalf of the companies. The project is also known as "WET-TEX: Implementacion de la tecnologia wet-laid en el desarrollo de nuevos textiles medico-sanitario" with expedient number IMIDIC/2010/137 (total grant of (sic)284,400) and the project "WET-TEX II: Implementacion de la tecnologia wet-laid en la investigacion y desarrollo de paneles para aplicaciones tecnicas a partir de residuos procedentes de la industria textil" with expedient number IMDEEA/2011/167 (total grant of (sic)255,000) funded by IMPIVA and cofunded (80%) by the European Union through FEDER funds, Valencian Community Operational 2007-2012.Fages, E.; Cano, MA.; Gironés, S.; Boronat Vitoria, T.; Fenollar Gimeno, OÁ.; Balart Gimeno, RA. (2013). The use of wet-laid techniques to obtain flax nonwovens with different thermoplastic binding fibers for technical insulation applications. Textile Research Journal. 83(4):426-437. https://doi.org/10.1177/0040517512454183S42643783

Use of atmospheric plasma treatment to improve adhesion properties of sodium ionomer sheets

“NOTICE: this is the author’s version of a work that was accepted for publication in Surface and Coatings Technology. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Surface and Coatings Technology, [VOL 218, (MAR 15 2013)] DOI10.1016/j.surfcoat.2012.12.016¨[EN] Polyolefins are characterized by having a low surface energy due to their non-polar nature, in the case of some ionomers, the base component is a polyolefin, thus relative poor adhesion properties are expected. As is widely known, for many industrial applications, such as coatings, paintings and formation of adhesive bonds, a high surface energy is required in order to provide good surface adhesion; for this reason the use of ionomers in these applications requires a previous surface treatment. In this paper surface treatment by atmospheric plasma has been used to provide surface activation to polyolefin-based sodium ionomers in order to improve their low intrinsic adhesion properties. This work has focused on the analysis of the influence of main process variables such as treatment rate and distance between nozzle and substrate to observe the improvement of adhesion properties at ionomer-polycarbonate adhesion joints subjected to shear and T-peel tests. After plasma treatment, T-peel force has increased six times it original value at most aggressive plasma parameters. Regarding on shear force, at same aggressive conditions of plasma treatment we achieved an increase of ten times its value of the shear sample without surface treatment, and its phenomenon can be seen in SEM pictures. (C) 2012 Elsevier B.V. All rights reserved.This work is part of the project IPT-310000-2010-037, "ECOTEXCOMP: Research and development of textile structures useful as reinforcement of composite materials with marked ecological character" funded by the "Ministerio de Ciencia e Innovacion", with an aid of 189540.20 euros, within the "Plan Nacional de Investigacion Cientifica, Desarrollo e InnovacionTecnologica 2008-2011" and funded by the European Union through FEDER funds, Technology Fund 2007-2013, Operational Programme on R + D + i for and on behalf of the companies. Also Generalitat Valenciana ref.: ACOMP/2012/087 is acknowledged for financial support. J.M. Espana wants to thank the Polytechnic University of Valencia (UPV) for their financial support through an FPI-UPV grant.España Giner, JM.; Boronat Vitoria, T.; García Sanoguera, D.; López Martínez, J.; Balart Gimeno, RA. (2013). Use of atmospheric plasma treatment to improve adhesion properties of sodium ionomer sheets. Surface and Coatings Technology. 218:1-6. https://doi.org/10.1016/j.surfcoat.2012.12.016S1621

Prevalence of metabolic syndrome in Murcia Region, a southern European Mediterranean area with low cardiovascular risk and high obesity

<p>Abstract</p> <p>Background</p> <p>Metabolic syndrome (MS) is associated with subsequent appearance of diabetes and cardiovascular disease. As compared to other Spanish regions, Murcia (southern Spain) registers increased obesity as well as cardiovascular morbidity and mortality. The aim of this study was to assess the prevalence of MS and its components, awareness of obesity as a health risk and associated lifestyles.</p> <p>Methods</p> <p>A population-based, cross-sectional study was conducted in 2003, covering a sample of 1555 individuals 20 years and over. MS was defined according to the Revised National Cholesterol Education Program Adult Treatment Panel III (R-ATPIII), International Diabetes Federation (IDF) and Joint Interim Statement (JIS) criteria. Both low (94/80) and high (102/88) waist circumference (WC) thresholds were considered.</p> <p>Results</p> <p>Prevalence of MS was 27.2% (95%CI: 25.2-29.2), 32.2% (95%CI: 30.1-34.3) and 33.2% (95%CI: 31.2-35.3) according to the R-ATPIII, IDF and JIS94/80 respectively. It increased with age until reaching 52.6% (R-ATPIII) or 60.3% (JIS94/80) among persons aged 70 years and over, and was higher in persons with little or no formal education (51.7% R-ATPIII, 57.3% JIS94/80). The most common risk factors were hypertension (46.6%) and central obesity (40.7% and 66.1% according to high and low WC cut-off points respectively). Although most persons were aware that obesity increased health risks, regular exercise was very unusual (13.0% centrally obese, 27.2% non-centrally obese). Adherence to dietary recommendations was similar among centrally obese and non-centrally obese subjects.</p> <p>Conclusions</p> <p>Prevalence of MS is high in our population, is comparable to that found in northern Europe and varies with the definition used. Adherence to preventive recommendations and to adequate weight promotion is very low. In the absence of a specific treatment for MS, integrated intervention based on a sustained increase in physical activity and changes in diet should be reinforced.</p

Differential Gene Expression and Epiregulation of Alpha Zein Gene Copies in Maize Haplotypes

Multigenic traits are very common in plants and cause diversity. Nutritional quality is such a trait, and one of its factors is the composition and relative expression of storage protein genes. In maize, they represent a medium-size gene family distributed over several chromosomes and unlinked locations. Two inbreds, B73 and BSSS53, both from the Iowa Stiff Stock Synthetic collection, have been selected to analyze allelic and non-allelic variability in these regions that span between 80–500 kb of chromosomal DNA. Genes were copied to unlinked sites before and after allotetraploidization of maize, but before transposition enlarged intergenic regions in a haplotype-specific manner. Once genes are copied, expression of donor genes is reduced relative to new copies. Epigenetic regulation seems to contribute to silencing older copies, because some of them can be reactivated when endosperm is maintained as cultured cells, indicating that copy number variation might contribute to a reserve of gene copies. Bisulfite sequencing of the promoter region also shows different methylation patterns among gene clusters as well as differences between tissues, suggesting a possible position effect on regulatory mechanisms as a result of inserting copies at unlinked locations. The observations offer a potential paradigm for how different gene families evolve and the impact this has on their expression and regulation of their members

Toll-Like Receptor 9 Is Required for Opioid-Induced Microglia Apoptosis

Opioids have been widely applied in clinics as one of the most potent pain relievers for centuries, but their abuse has deleterious physiological effects beyond addiction. However, the underlying mechanism by which microglia in response to opioids remains largely unknown. Here we show that morphine induces the expression of Toll-like receptor 9 (TLR9), a key mediator of innate immunity and inflammation. Interestingly, TLR9 deficiency significantly inhibited morphine-induced apoptosis in microglia. Similar results were obtained when endogenous TLR9 expression was suppressed by the TLR9 inhibitor CpGODN. Inhibition of p38 MAPK by its specific inhibitor SB203580 attenuated morphine-induced microglia apoptosis in wild type microglia. Morphine caused a dramatic decrease in Bcl-2 level but increase in Bax level in wild type microglia, but not in TLR9 deficient microglia. In addition, morphine treatment failed to induce an increased levels of phosphorylated p38 MAPK and MAP kinase kinase 3/6 (MKK3/6), the upstream MAPK kinase of p38 MAPK, in either TLR9 deficient or µ-opioid receptor (µOR) deficient primary microglia, suggesting an involvement of MAPK and µOR in morphine-mediated TLR9 signaling. Moreover, morphine-induced TLR9 expression and microglia apoptosis appears to require μOR. Collectively, these results reveal that opioids prime microglia to undergo apoptosis through TLR9 and µOR as well. Taken together, our data suggest that inhibition of TLR9 and/or blockage of µOR is capable of preventing opioid-induced brain damage

Generation of subnanometric platinum with high stability during transformation of a 2D zeolite into 3D

[EN] Single metal atoms and metal clusters have attracted much attention thanks to their advantageous capabilities as heterogeneous catalysts. However, the generation of stable single atoms and clusters on a solid support is still challenging. Herein, we report a new strategy for the generation of single Pt atoms and Pt clusters with exceptionally high thermal stability, formed within purely siliceous MCM-22 during the growth of a two-dimensional zeolite into three dimensions. These subnanometric Pt species are stabilized by MCM-22, even after treatment in air up to 540 degrees C. Furthermore, these stable Pt species confined within internal framework cavities show size-selective catalysis for the hydrogenation of alkenes. High-temperature oxidation-reduction treatments result in the growth of encapsulated Pt species to small nanoparticles in the approximate size range of 1 to 2 nm. The stability and catalytic activity of encapsulated Pt species is also reflected in the dehydrogenation of propane to propylene.This work was funded by the Spanish Government (Consolider Ingenio 2010-MULTICAT (CSD2009-00050) and MAT2014-52085-C2-1-P) and by the Generalitat Valenciana (Prometeo). The Severo Ochoa Program (SEV-2012-0267) is gratefully acknowledged. L.L. thanks ITQ for a contract. The authors also thank the Microscopy Service of UPV for the TEM and STEM measurements. The HAADF-HRSTEM works were conducted in the Laboratorio de Microscopias Avanzadas (LMA) at the Instituto de Nanociencia de Aragon (INA)-Universidad de Zaragoza (Spain), a Spanish ICTS National Facility. Some of the research leading to these results has received funding from the European Union Seventh Framework Program under Grant Agreement 312483-ESTEEM2 (Integrated Infrastructure Initiative-I3). R.A. also acknowledges funding from the Spanish Ministerio de Economia y Competitividad (FIS2013-46159-C3-3-P) and the European Union Horizon 2020 research and innovation programme under the Marie Sldodowska-Curie grant agreement No. 642742.Liu, L.; Díaz Morales, UM.; Arenal, R.; Agostini, G.; Concepción Heydorn, P.; Corma Canós, A. (2017). Generation of subnanometric platinum with high stability during transformation of a 2D zeolite into 3D. Nature Materials. 16(1):132-138. https://doi.org/10.1038/NMAT4757S132138161Boronat, M., Leyva-Perez, A. & Corma, A. Theoretical and experimental insights into the origin of the catalytic activity of subnanometric gold clusters: attempts to predict reactivity with clusters and nanoparticles of gold. Acc. Chem. Res. 47, 834–844 (2014).Flytzani-Stephanopoulos, M. & Gates, B. C. Atomically dispersed supported metal catalysts. Ann. Rev. Chem. Bio. Eng. 3, 545–574 (2012).Gates, B. C. Supported metal clusters: synthesis, structure, and catalysis. Chem. 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