The diversification-performance relationship in Spanish firms : does the CEO´S behaviour style matter?

The agency-stewardship theoretical framework posits that CEOs may choose to act as agents or as stewards. CEOs as agents are economically rational individuals driven by self-interest, whereas CEOs as stewards are self-actualizing individuals that behave pro-organizationally. Our study extends this framework to analyze whether the CEO´s behavior style affects the diversification-performance relationship. After applying Heckman´s method on a sample of Spanish firms, our results verify that diversification affects positively on firm performance and such effect is significantly strong when this strategy is managed and implemented by a CEO inclined to behave as steward.peer-reviewe

How important is the European economic and monetary union in the foreign trade with the EU-27 countries? Empirical evidence from Spain

This paper analyzes the effect of the European Economic and Monetary Union on export flows from a Spanish region (Castilla y Leon) to the EU-27 countries during the last years Applying static panel data estimation technique, this study finds that exporter and importer incomes, exporter population, distance, and a common land border are the main explanatory factors of exports from this Spanish region. Moreover, the EU membership of the importer country only caused positive and significant effects between 1994 and 1996, whereas the EMU membership reduced export flows from Castilla y Leon to the European countries during the whole period.peer-reviewe

Fibronectin fixation on poly(ethyl acrylate)-based copolymer

The aim of this paper is to quantify the adhered fibronectin (FN; by adsorption and/or grafting) and the exposure of its cell adhesive motifs (RGD and FNIII7-10) on poly(ethyl acrylate) (PEA) copolymers whose chemical composition has been designed to increase wettability and to introduce acid functional groups. FN was adsorbed to PEA, poly(ethyl acrylate-co-hydroxyethyl acrylate), poly(ethyl acrylate-co-acrylic acid), and poly(ethyl acrylate-co-methacrylic acid) copolymers, and covalently cross-linked to poly(ethyl acrylate-co-acrylic acid) and poly(ethyl acrylate-co-methacrylic acid) copolymers. Amount of adhered FN and exhibition of RGD and FNIII7-10 fragments involved in cell adhesion were quantified with enzyme-linked immunosorbent assay tests. Even copolymers with a lower content of the hydrophilic component showed a decrease in water contact angle. In addition, FN was successfully fixed on all surfaces, especially on the hydrophobic surfaces. However, it was demonstrated that exposure of its cell adhesion sequences, which is the key factor in cell adhesion and proliferation, was higher for hydrophilic surfaces. (c) 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2013.Contract grant sponsors: Centre for Industrial Technological Development (CDTI) of Ministry of Economy and Competitiveness, Project Customized Eye Care-Oftalmologia personalizada _CEYEC CENIT-Sol 00028336 SFPECEPP and Health Institute Carlos III through the CIBER- BBN (Bioingenieria, Biomateriales y Nanomedicina); CIBER-BBN is an initiative funded by the VI National R&D&i Plan 2008-2011, Iniciativa Ingenio 2010, Consolider Program, CIBER Actions and financed by the Instituto de Salud Carlos III with assistance from the European Regional Development FundBriz, N.; Antolinos Turpín, CM.; Alio, J.; Garagorri, N.; Gómez Ribelles, JL.; Gómez-Tejedor, JA. (2013). Fibronectin fixation on poly(ethyl acrylate)-based copolymer. Journal of Biomedical Materials Research Part B: Applied Biomaterials. 101B(6):991-997. https://doi.org/10.1002/jbm.b.32907S991997101B6Roach, P., Eglin, D., Rohde, K., & Perry, C. C. (2007). Modern biomaterials: a review—bulk properties and implications of surface modifications. Journal of Materials Science: Materials in Medicine, 18(7), 1263-1277. doi:10.1007/s10856-006-0064-3Schmidt, D. R., Waldeck, H., & Kao, W. J. (2009). Protein Adsorption to Biomaterials. Biological Interactions on Materials Surfaces, 1-18. doi:10.1007/978-0-387-98161-1_1Ertel, S. I., Ratner, B. D., & Horbett, T. A. (1990). Radiofrequency plasma deposition of oxygen-containing films on polystyrene and poly(ethylene terephthalate) substrates improves endothelial cell growth. Journal of Biomedical Materials Research, 24(12), 1637-1659. doi:10.1002/jbm.820241207Way, T.-D., Hsieh, S.-R., Chang, C.-J., Hung, T.-W., & Chiu, C.-H. (2010). Preparation and characterization of branched polymers as postoperative anti-adhesion barriers. Applied Surface Science, 256(10), 3330-3336. doi:10.1016/j.apsusc.2009.12.029Hsieh, S.-R., Chang, C.-J., Way, T.-D., Kwan, P.-C., & Hung, T.-W. (2009). Preparation and Non-Invasive In-Vivo Imaging of Anti-Adhesion Barriers with Fluorescent Polymeric Marks. Journal of Fluorescence, 19(4), 733-740. doi:10.1007/s10895-009-0469-8Lee, M. H., Ducheyne, P., Lynch, L., Boettiger, D., & Composto, R. J. (2006). Effect of biomaterial surface properties on fibronectin–α5β1 integrin interaction and cellular attachment. Biomaterials, 27(9), 1907-1916. doi:10.1016/j.biomaterials.2005.11.003Keselowsky, B. G., Collard, D. M., & Garcı́a, A. J. (2004). Surface chemistry modulates focal adhesion composition and signaling through changes in integrin binding. Biomaterials, 25(28), 5947-5954. doi:10.1016/j.biomaterials.2004.01.062Tzoneva, R., Faucheux, N., & Groth, T. (2007). Wettability of substrata controls cell–substrate and cell–cell adhesions. Biochimica et Biophysica Acta (BBA) - General Subjects, 1770(11), 1538-1547. doi:10.1016/j.bbagen.2007.07.008Rico, P., Hernández, J. C. R., Moratal, D., Altankov, G., Pradas, M. M., & Salmerón-Sánchez, M. (2009). Substrate-Induced Assembly of Fibronectin into Networks: Influence of Surface Chemistry and Effect on Osteoblast Adhesion. Tissue Engineering Part A, 15(11), 3271-3281. doi:10.1089/ten.tea.2009.0141Gugutkov, D., Altankov, G., Rodríguez Hernández, J. C., Monleón Pradas, M., & Salmerón Sánchez, M. (2010). Fibronectin activity on substrates with controlled OH density. Journal of Biomedical Materials Research Part A, 92A(1), 322-331. doi:10.1002/jbm.a.32374Salmerón-Sánchez, M., Rico, P., Moratal, D., Lee, T. T., Schwarzbauer, J. E., & García, A. J. (2011). Role of material-driven fibronectin fibrillogenesis in cell differentiation. Biomaterials, 32(8), 2099-2105. doi:10.1016/j.biomaterials.2010.11.057Pérez Olmedilla, M., Garcia-Giralt, N., Pradas, M. M., Ruiz, P. B., Gómez Ribelles, J. L., Palou, E. C., & García, J. C. M. (2006). Response of human chondrocytes to a non-uniform distribution of hydrophilic domains on poly (ethyl acrylate-co-hydroxyethyl methacrylate) copolymers. Biomaterials, 27(7), 1003-1012. doi:10.1016/j.biomaterials.2005.07.030Soria, J. M., Martínez Ramos, C., Salmerón Sánchez, M., Benavent, V., Campillo Fernández, A., Gómez Ribelles, J. L., … Barcia, J. A. (2006). Survival and differentiation of embryonic neural explants on different biomaterials. Journal of Biomedical Materials Research Part A, 79A(3), 495-502. doi:10.1002/jbm.a.30803Campillo-Fernandez, A. J., Pastor, S., Abad-Collado, M., Bataille, L., Gomez-Ribelles, J. L., Meseguer-Dueñas, J. M., … Ruiz-Moreno, J. M. (2007). Future Design of a New Keratoprosthesis. Physical and Biological Analysis of Polymeric Substrates for Epithelial Cell Growth. Biomacromolecules, 8(8), 2429-2436. doi:10.1021/bm0703012Campillo-Fernández, A. J., Unger, R. E., Peters, K., Halstenberg, S., Santos, M., Sánchez, M. S., … Kirkpatrick, C. J. (2009). Analysis of the Biological Response of Endothelial and Fibroblast Cells Cultured on Synthetic Scaffolds with Various Hydrophilic/Hydrophobic Ratios: Influence of Fibronectin Adsorption and Conformation. Tissue Engineering Part A, 15(6), 1331-1341. doi:10.1089/ten.tea.2008.0146Cutler, S. (2003). Engineering cell adhesive surfaces that direct integrin α5β1 binding using a recombinant fragment of fibronectin. Biomaterials, 24(10), 1759-1770. doi:10.1016/s0142-9612(02)00570-7Salmerón Sánchez, M., Brı́gido Diego, R., Iannazzo, S. A. ., Gómez Ribelles, J. L., & Monleón Pradas, M. (2004). The structure of poly(ethyl acrylate-co-hydroxyethyl methacrylate) copolymer networks by segmental dynamics studies based on structural relaxation experiments. Polymer, 45(7), 2349-2355. doi:10.1016/j.polymer.2004.01.043Campillo-Fernández, A. J., Salmerón Sánchez, M., Sabater i Serra, R., Meseguer Dueñas, J. M., Monleón Pradas, M., & Gómez Ribelles, J. L. (2008). Water-induced (nano) organization in poly(ethyl acrylate-co-hydroxyethyl acrylate) networks. European Polymer Journal, 44(7), 1996-2004. doi:10.1016/j.eurpolymj.2008.04.032Lan, M. A., Gersbach, C. A., Michael, K. E., Keselowsky, B. G., & García, A. J. (2005). Myoblast proliferation and differentiation on fibronectin-coated self assembled monolayers presenting different surface chemistries. Biomaterials, 26(22), 4523-4531. doi:10.1016/j.biomaterials.2004.11.02

Morphology, Crystallinity, and Molecular Weight of Poly(E-caprolactone)/Graphene Oxide Hybrids

[EN] A study was carried out to determine the effects of graphene oxide (GO) filler on the properties of poly(epsilon-caprolactone) (PCL) films. A series of nanocomposites were prepared, incorporating different graphene oxide filler contents (0.1, 0.2, and 0.5 wt%) by the solution mixing method, and an in-depth study was made of the morphological changes, crystallization, infrared absorbance, molecular weight, thermal properties, and biocompatibility as a function of GO content to determine their suitability for use in biomedical applications. The infrared absorbance showed the existence of intermolecular hydrogen bonds between the PCL's carbonyl groups and the GO's hydrogen-donating groups, which is in line with the apparent reduction in molecular weight at higher GO contents, indicated by the results of the gel permeation chromatography (GPC), and the thermal property analysis. Polarized optical microscopy (POM) showed that GO acts as a nucleating point for PCL crystals, increasing crystallinity and crystallization temperature. The biological properties of the composites studied indicate that adding only 0.1 wt% of GO can improve cellular viability and that the composite shows promise for use in biomedical applications.This work was supported by Projects GV/2016/067 of the Generalitat Valenciana and MAT2016-76039-C4-3-R of the Spanish Ministry of Economy and Competitiveness (MINECO). The authors are grateful to M. Monleon-Pradas for his helpful comments and G. Vilarino-Feltrer for his valuable advice on the cell culture experiments. A. Vidaurre would also like to express her gratitude for the support received from CIBER-BBN, an initiative funded by the VI National R&D&i Plan 2008-2011, Iniciativa Ingenio 2010, Consolider Program, CIBER Actions financed by the Instituto de Salud Carlos III with assistance from the European Regional Development Fund. SEM, TEM and AFM were conducted by the authors at the Microscopy Service of the Universitat Politecnica de Valencia, whose advice is greatly appreciated.Castilla Cortázar, MIC.; Vidaurre, A.; Marí, B.; Campillo Fernandez, AJ. (2019). Morphology, Crystallinity, and Molecular Weight of Poly(E-caprolactone)/Graphene Oxide Hybrids. Polymers. 11(7):1-19. https://doi.org/10.3390/polym11071099S119117Hummers, W. S., & Offeman, R. E. (1958). Preparation of Graphitic Oxide. Journal of the American Chemical Society, 80(6), 1339-1339. doi:10.1021/ja01539a017Stankovich, S., Piner, R. D., Nguyen, S. T., & Ruoff, R. S. (2006). Synthesis and exfoliation of isocyanate-treated graphene oxide nanoplatelets. Carbon, 44(15), 3342-3347. doi:10.1016/j.carbon.2006.06.004Dreyer, D. R., Park, S., Bielawski, C. W., & Ruoff, R. S. (2010). The chemistry of graphene oxide. Chem. Soc. Rev., 39(1), 228-240. doi:10.1039/b917103gKonios, D., Stylianakis, M. M., Stratakis, E., & Kymakis, E. (2014). Dispersion behaviour of graphene oxide and reduced graphene oxide. Journal of Colloid and Interface Science, 430, 108-112. doi:10.1016/j.jcis.2014.05.033Kuilla, T., Bhadra, S., Yao, D., Kim, N. H., Bose, S., & Lee, J. H. (2010). Recent advances in graphene based polymer composites. Progress in Polymer Science, 35(11), 1350-1375. doi:10.1016/j.progpolymsci.2010.07.005Potts, J. R., Dreyer, D. R., Bielawski, C. W., & Ruoff, R. S. (2011). Graphene-based polymer nanocomposites. Polymer, 52(1), 5-25. doi:10.1016/j.polymer.2010.11.042Liang, J., Huang, Y., Zhang, L., Wang, Y., Ma, Y., Guo, T., & Chen, Y. (2009). Molecular-Level Dispersion of Graphene into Poly(vinyl alcohol) and Effective Reinforcement of their Nanocomposites. Advanced Functional Materials, 19(14), 2297-2302. doi:10.1002/adfm.200801776Han, D., Yan, L., Chen, W., & Li, W. (2011). Preparation of chitosan/graphene oxide composite film with enhanced mechanical strength in the wet state. Carbohydrate Polymers, 83(2), 653-658. doi:10.1016/j.carbpol.2010.08.038Luong, N. D., Hippi, U., Korhonen, J. T., Soininen, A. J., Ruokolainen, J., Johansson, L.-S., … Seppälä, J. (2011). Enhanced mechanical and electrical properties of polyimide film by graphene sheets via in situ polymerization. Polymer, 52(23), 5237-5242. doi:10.1016/j.polymer.2011.09.033Yang, X., Tu, Y., Li, L., Shang, S., & Tao, X. (2010). Well-Dispersed Chitosan/Graphene Oxide Nanocomposites. ACS Applied Materials & Interfaces, 2(6), 1707-1713. doi:10.1021/am100222mSalavagione, H. J., Gómez, M. A., & Martínez, G. (2009). Polymeric Modification of Graphene through Esterification of Graphite Oxide and Poly(vinyl alcohol). Macromolecules, 42(17), 6331-6334. doi:10.1021/ma900845wXu, Z., & Gao, C. (2010). In situ Polymerization Approach to Graphene-Reinforced Nylon-6 Composites. Macromolecules, 43(16), 6716-6723. doi:10.1021/ma1009337Kulkarni, D. D., Choi, I., Singamaneni, S. S., & Tsukruk, V. V. (2010). Graphene Oxide−Polyelectrolyte Nanomembranes. ACS Nano, 4(8), 4667-4676. doi:10.1021/nn101204dBao, C., Guo, Y., Song, L., & Hu, Y. (2011). Poly(vinyl alcohol) nanocomposites based on graphene and graphite oxide: a comparative investigation of property and mechanism. Journal of Materials Chemistry, 21(36), 13942. doi:10.1039/c1jm11662bTang, L.-C., Wan, Y.-J., Yan, D., Pei, Y.-B., Zhao, L., Li, Y.-B., … Lai, G.-Q. (2013). The effect of graphene dispersion on the mechanical properties of graphene/epoxy composites. Carbon, 60, 16-27. doi:10.1016/j.carbon.2013.03.050Song, Y. S., & Youn, J. R. (2005). Influence of dispersion states of carbon nanotubes on physical properties of epoxy nanocomposites. Carbon, 43(7), 1378-1385. doi:10.1016/j.carbon.2005.01.007Kim, H., Miura, Y., & Macosko, C. W. (2010). Graphene/Polyurethane Nanocomposites for Improved Gas Barrier and Electrical Conductivity. Chemistry of Materials, 22(11), 3441-3450. doi:10.1021/cm100477vAhmad, H., Fan, M., & Hui, D. (2018). Graphene oxide incorporated functional materials: A review. Composites Part B: Engineering, 145, 270-280. doi:10.1016/j.compositesb.2018.02.006Kai, W., Hirota, Y., Hua, L., & Inoue, Y. (2007). Thermal and mechanical properties of a poly(ε-caprolactone)/graphite oxide composite. Journal of Applied Polymer Science, 107(3), 1395-1400. doi:10.1002/app.27210Woodruff, M. A., & Hutmacher, D. W. (2010). The return of a forgotten polymer—Polycaprolactone in the 21st century. Progress in Polymer Science, 35(10), 1217-1256. doi:10.1016/j.progpolymsci.2010.04.002Wan, C., & Chen, B. (2011). Poly(ε-caprolactone)/graphene oxide biocomposites: mechanical properties and bioactivity. Biomedical Materials, 6(5), 055010. doi:10.1088/1748-6041/6/5/055010Song, J., Gao, H., Zhu, G., Cao, X., Shi, X., & Wang, Y. (2015). The preparation and characterization of polycaprolactone/graphene oxide biocomposite nanofiber scaffolds and their application for directing cell behaviors. Carbon, 95, 1039-1050. doi:10.1016/j.carbon.2015.09.011Hua, L., Kai, W. H., & Inoue, Y. (2007). Crystallization behavior of poly(ϵ-caprolactone)/graphite oxide composites. Journal of Applied Polymer Science, 106(6), 4225-4232. doi:10.1002/app.26976Sayyar, S., Murray, E., Thompson, B. C., Gambhir, S., Officer, D. L., & Wallace, G. G. (2013). Covalently linked biocompatible graphene/polycaprolactone composites for tissue engineering. Carbon, 52, 296-304. doi:10.1016/j.carbon.2012.09.031Murray, E., Sayyar, S., Thompson, B. C., Gorkin III, R., Officer, D. L., & Wallace, G. G. (2015). A bio-friendly, green route to processable, biocompatible graphene/polymer composites. RSC Advances, 5(56), 45284-45290. doi:10.1039/c5ra07210gHassanzadeh, S., Adolfsson, K. H., Wu, D., & Hakkarainen, M. (2015). Supramolecular Assembly of Biobased Graphene Oxide Quantum Dots Controls the Morphology of and Induces Mineralization on Poly(ε-caprolactone) Films. Biomacromolecules, 17(1), 256-261. doi:10.1021/acs.biomac.5b01339Kumar, S., Azam, D., Raj, S., Kolanthai, E., Vasu, K. S., Sood, A. K., & Chatterjee, K. (2015). 3D scaffold alters cellular response to graphene in a polymer composite for orthopedic applications. Journal of Biomedical Materials Research Part B: Applied Biomaterials, 104(4), 732-749. doi:10.1002/jbm.b.33549Shin, S. R., Li, Y.-C., Jang, H. L., Khoshakhlagh, P., Akbari, M., Nasajpour, A., … Khademhosseini, A. (2016). Graphene-based materials for tissue engineering. Advanced Drug Delivery Reviews, 105, 255-274. doi:10.1016/j.addr.2016.03.007Bianco, A. (2013). Graphene: Safe or Toxic? The Two Faces of the Medal. Angewandte Chemie International Edition, 52(19), 4986-4997. doi:10.1002/anie.201209099Zhang, X., Yin, J., Peng, C., Hu, W., Zhu, Z., Li, W., … Huang, Q. (2011). Distribution and biocompatibility studies of graphene oxide in mice after intravenous administration. 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Dual Functions of Highly Potent Graphene Derivative–Poly-l-Lysine Composites To Inhibit Bacteria and Support Human Cells. ACS Nano, 6(8), 7151-7161. doi:10.1021/nn302215ySydlik, S. A., Jhunjhunwala, S., Webber, M. J., Anderson, D. G., & Langer, R. (2015). In Vivo Compatibility of Graphene Oxide with Differing Oxidation States. ACS Nano, 9(4), 3866-3874. doi:10.1021/acsnano.5b01290Crescenzi, V., Manzini, G., Calzolari, G., & Borri, C. (1972). Thermodynamics of fusion of poly-β-propiolactone and poly-ϵ-caprolactone. comparative analysis of the melting of aliphatic polylactone and polyester chains. European Polymer Journal, 8(3), 449-463. doi:10.1016/0014-3057(72)90109-7Luo, H., Meng, X., Cheng, C., Dong, Z., Zhang, S., & Li, B. (2010). Enzymatic Degradation of Supramolecular Materials Based on Partial Inclusion Complex Formation between α-Cyclodextrin and Poly(ε-caprolactone). The Journal of Physical Chemistry B, 114(13), 4739-4745. doi:10.1021/jp1001836Vidaurre, A., Dueñas, J. M. M., Estellés, J. M., & Cortázar, I. C. (2008). Influence of Enzymatic Degradation on Physical Properties of Poly(ε-caprolactone) Films and Sponges. Macromolecular Symposia, 269(1), 38-46. doi:10.1002/masy.200850907Honma, T., Senda, T., & Inoue, Y. (2003). Thermal properties and crystallization behaviour of blends of poly(?-caprolactone) with chitin and chitosan. Polymer International, 52(12), 1839-1846. doi:10.1002/pi.1380Ramazani, S., & Karimi, M. (2015). Aligned poly(ε-caprolactone)/graphene oxide and reduced graphene oxide nanocomposite nanofibers: Morphological, mechanical and structural properties. Materials Science and Engineering: C, 56, 325-334. doi:10.1016/j.msec.2015.06.045Coleman, M. M., & Zarian, J. (1979). Fourier-transform infrared studies of polymer blends. II. Poly(ε-caprolactone)–poly(vinyl chloride) system. Journal of Polymer Science: Polymer Physics Edition, 17(5), 837-850. doi:10.1002/pol.1979.180170509Huang, Y., Xu, Z., Huang, Y., Ma, D., Yang, J., & Mays, J. W. (2003). Characterization of Poly(ε-Caprolactone) via Size Exclusion Chromatography with Online Right-Angle Laser-Light Scattering and Viscometric Detectors. International Journal of Polymer Analysis and Characterization, 8(6), 383-394. doi:10.1080/714975019Sharaf, M. A., Kloczkowski, A., Sen, T. Z., Jacob, K. I., & Mark, J. E. (2006). Filler-induced deformations of amorphous polyethylene chains. The effects of the deformations on elastomeric properties, and some comparisons with experiments. European Polymer Journal, 42(4), 796-806. doi:10.1016/j.eurpolymj.2005.10.009Nusser, K., Neueder, S., Schneider, G. J., Meyer, M., Pyckhout-Hintzen, W., Willner, L., … Richter, D. (2010). Conformations of Silica−Poly(ethylene−propylene) Nanocomposites. Macromolecules, 43(23), 9837-9847. doi:10.1021/ma101898cVacatello, M. (2002). Chain Dimensions in Filled Polymers:  An Intriguing Problem. Macromolecules, 35(21), 8191-8193. doi:10.1021/ma020416sDuan, T., Lv, Y., Xu, H., Jin, J., & Wang, Z. (2018). Structural Effects of Residual Groups of Graphene Oxide on Poly(ε-Caprolactone)/Graphene Oxide Nanocomposite. Crystals, 8(7), 270. doi:10.3390/cryst8070270Wang, G., Wei, Z., Sang, L., Chen, G., Zhang, W., Dong, X., & Qi, M. (2013). Morphology, crystallization and mechanical properties of poly(ɛ-caprolactone)/graphene oxide nanocomposites. Chinese Journal of Polymer Science, 31(8), 1148-1160. doi:10.1007/s10118-013-1278-8Balkova, R., Hermanova, S., Voberkova, S., Damborsky, P., Richtera, L., Omelkova, J., & Jancar, J. (2013). Structure and Morphology of Microbial Degraded Poly(ε-caprolactone)/Graphite Oxide Composite. Journal of Polymers and the Environment, 22(2), 190-199. doi:10.1007/s10924-013-0630-yYıldırım, S., Demirtaş, T. T., Dinçer, C. A., Yıldız, N., & Karakeçili, A. (2018). Preparation of polycaprolactone/graphene oxide scaffolds: A green route combining supercritial CO2 technology and porogen leaching. 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Analysis of the 'Endoworm' prototype's ability to grip the bowel in in vitro and ex vivo models

[EN] Access to the small bowel by means of an enteroscope is difficult, even using current devices such as single-balloon or double-balloon enteroscopes. Exploration time and patient discomfort are the main drawbacks. The prototype 'Endoworm' analysed in this paper is based on a pneumatic translation system that, gripping the bowel, enables the endoscope to move forward while the bowel slides back over its most proximal part. The grip capacity is related to the pressure inside the balloon, which depends on the insufflate volume of air. Different materials were used as in vitro and ex vivo models: rigid polymethyl methacrylate, flexible silicone, polyester urethane and ex vivo pig small bowel. On measuring the pressure-volume relationship, we found that it depended on the elastic properties of the lumen and that the frictional force depended on the air pressure inside the balloons and the lumen's elastic properties. In the presence of a lubricant, the grip on the simulated intestinal lumens was drastically reduced, as was the influence of the lumen's properties. This paper focuses on the Endoworm's ability to grip the bowel, which is crucial to achieving effective endoscope forward advance and bowel foldingThe author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: The study was funded by the Spanish Ministry of Economy and Competitiveness through Project (PI18/01365) and by the UPV/IIS LA Fe through the (Endoworm 3.0) Project. CIBER-BBN is an initiative funded by the VI National R&D&I Plan 2008-2011, Iniciativa Ingenio 2010, Consolider Program, CIBER Actions and financed by the Instituto de Salud Carlos III with the assistance of the European Regional Development FundTobella, J.; Pons-Beltrán, V.; Santonja, A.; Sánchez-Diaz, C.; Campillo Fernandez, AJ.; Vidaurre, A. (2020). 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Caracterización de residuos procedentes de los procesos de combustión de biomasa. Viabilidad de uso como materiales de Construcción.

En España, y más específicamente en Andalucía, la producción de energía a partir de la quema de biomasa presenta una actividad creciente, por lo que la caracterización de los residuos procedentes de esta combustión facilitaría su empleo futuro. En el presente trabajo se estudia la viabilidad técnica que presentan ciertos residuos (cenizas volantes y cenizas de fondo) procedentes de dicha combustión, para ser empleados en materiales de construcción, evaluando la composición química y mineralógica de estos residuos. Los resultados obtenidos muestran que los residuos analizados poseen propiedades aceptables para ser utilizados en la producción de materiales que tomen como base el cemento, si bien su calidad y tipo de aplicación depende de la procedencia del residu

Materials Science Toolkit for Carbon Footprint Assessment: A Case Study for Endoscopic Accessories of Common Use

[EN] Ironically, healthcare systems are key agents in respiratory-related diseases and estimated deaths because of the high impact of their greenhouse gas emissions, along with industry, transportation, and housing. Based on safety requirements, hospitals and related services use an extensive number of consumables, most of which end up incinerated at the end of their life cycle. A thorough assessment of the carbon footprint of such devices typically requires knowing precise information about the manufacturing process, rarely available in detail because of the many materials, pieces and steps involved during the fabrication. And yet, tools most often used for determining the environmental impact of consumer goods just require a bunch of parameters, mainly based on the material composition of the device. Here we report a basic set of analytical methods that provide the information required by the software OpenLCA to calculate the main outcome related to environmental impact, the greenhouse gas emissions. Through thermogravimetry, calorimetry, infrared spectroscopy and elemental analysis we proved that obtaining relevant data for the calculator in the exemplifying case of endoscopy tooling or accessories is possible. This routine procedure opens the door to a broader, more accurate analysis of the environmental impact of everyday work at hospital services, offering potential alternatives to minimize it.This study has been funded by Instituto de Salud Carlos III (ISCIII) through the project PI21/00193 and cofunded by the European Union. Funding: Instituto de Salud Carlos III (ISCIII), PI21/00193, cofunded by the European Union. And through the project PI2023-6 from UPV-LaFe innovation projects.Martín-Cabezuelo, R.; Vilariño-Feltrer, G.; Campillo Fernandez, AJ.; Lorenzo-Zúñiga, V.; Pons, V.; López-Muñoz, P.; Tort-Ausina, I. (2023). Materials Science Toolkit for Carbon Footprint Assessment: A Case Study for Endoscopic Accessories of Common Use. ACS Environmental Au. https://doi.org/10.1021/acsenvironau.3c0004

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The Andalusian eHealth Library (Biblioteca Virtual del Sistema Sanitario Publico de Andalucia, BV-SSPA), was created in June 2006. The 42 librarians who already worked for the Health System were integrated within this new system. The annual library meeting has been held every year since then, and in 2013 the EAHIL workshop held in Stockholm was the model to follow

Prognostic Significance of Infection Acquisition Sites in Spontaneous Bacterial Peritonitis: Nosocomial versus Community Acquired

Spontaneous bacterial peritonitis (SBP) is an ascitic fluid infection as a complication of end stage liver disease. The outcome is related to the severity of hepatorenal function, gastrointestinal bleeding, and many others; however it is not well known whether the infection acquisition sites have an effect on the prognosis of SBP. In order to identify the prognostic significance of the acquisition sites, we studied 106 patients who were diagnosed as culture positive SBP between October 1998 and August 2003. Thirty-two episodes were nosocomial and 74 were community acquired. Gram-negative bacilli such as Escherichia coli were dominant in both of the nosocomial and community-acquired SBPs. Despite significantly higher resistance to cefotaxime in nosocomial isolates compared to community-acquired isolates (77.8% vs. 13.6%, p=0.001), no difference was found regarding short or long term prognosis. Infection acquisition sites were not related to short or long term prognosis either. Shock, gastrointestinal bleeding and renal dysfunction were related to short term prognosis. Only Child-Pugh class C was identified as an independent prognostic factor of long-term survival