Xylan-lignin (XL), glucomannan-lignin (GML) and glucan-lignin (GL) complexes were isolated from spruce wood, hydrolyzed with xylanase or endoglucanase/β-glucosidase, and analyzed by analytical pyrolysis and 2D-NMR. The enzymatic hydrolysis removed most of the polysaccharide moieties in the complexes, and the lignin content and relative abundance of lignin-carbohydrate linkages increased. Analytical pyrolysis confirmed the action of the enzymatic hydrolysis, with strong decreases of levoglucosane and other carbohydrate-derived products. Unexpectedly it also revealed that the hydrolase treatment alters the pattern of lignin breakdown products, resulting in higher amounts of coniferyl alcohol. From the anomeric carbohydrate signals in the 2D-NMR spectra, phenyl glycoside linkages (undetectable in the original complexes) could be identified in the hydrolyzed GML complex. Lower amounts of glucuronosyl and benzyl ether linkages were also observed after the hydrolysis. From the 2D-NMR spectra of the hydrolyzed complexes, it was concluded that the lignin in GML is less condensed than in XL due to its higher content in β-O-4' ether substructures (62 % of side chains in GML vs 53 % in XL) accompanied by more coniferyl alcohol end units (16 vs 13 %). In contrast, the XL lignin has more pinoresinols (11 vs 6 %) and dibenzodioxocins (9 vs 2 %) than the GML (and both have ~13 % phenylcoumarans and 1 % spirodienones). Direct 2D-NMR analysis of the hydrolyzed GL complex was not possible due to its low solubility. However, after sample acetylation, an even less condensed lignin than in the GML complex was found (with up to 72 % β-O-4' substructures and only 1 % pinoresinols). The study provides evidence for the existence of structurally different lignins associated to hemicelluloses (xylan and glucomannan) and cellulose in spruce wood and, at the same time, offers information on some of the chemical linkages between the above polymers.
Security must be a primary concern when engineering Future Internet (FI) systems and applications. In order to achieve secure solutions, we need to capture security requirements early in the Software Development Life Cycle (SDLC). Whereas the security community has traditionally focused on providing tools and mechanisms to capture and express hard security requirements (e.g. confidentiality), little attention has been paid to other important requirements such as trust and reputation. We argue that these soft security requirements can leverage security in open, distributed, heterogeneous systems and applications and that they must be included in an early phase as part of the development process. In this paper we propose a UML extension for specifying trust and reputation requirements, and we apply it to an eHealth case study.
Se analiza, con una visión crítica, el catálogo de sanciones previsto en la Ley Orgánica 4/2015, de 30 de marzo, de Protección de la Seguridad Ciudadana. A propósito de este estudio, se pone de manifiesto que algunas de las sanciones accesorias previstas en esta ley parecen más enfocadas a garantizar la seguridad ciudadana que a castigar al sujeto infractor. Igualmente, se sugiere la posibilidad de que el legislador prevea algunas sanciones no pecuniarias, sobre todo cuando se trata de reprimir conductas de menores de edad o sujetos insolventes. A la vez que se realiza este estudio, se lleva a cabo una comparación con el ordenamiento jurídico italiano, donde se apuesta mucho más por la prevención y limitación que por la sanción, también en el ámbito de la seguridad ciudadana. En último lugar, se analizan algunas medidas limitativas previstas en las leyes italianas para evitar perturbaciones del orden público y se plantea su viabilidad en el ordenamiento español.
Ya no es novedoso que las autoridades de defensa de la competencia puedan sancionar a las personas públicas, incluso a las Administraciones, por infracciones contra la competencia. Pero hasta ahora eso sólo se aceptaba en tanto que las Administraciones o sus entes institucionales actuaran como empresas. Hace algunos años la Comisión Nacional de la Competencia decidió que también cabía sancionar a las Administraciones cuando, actuando como poderes públicos, restringen la competencia. Lo hizo, además, considerando que la Administración actuaba como "facilitador" de la infracción, figura en sí misma cuestionable. Ahora los Tribunales han aceptado aquella construcción. En este trabajo se da cuenta de aquellas resoluciones y de estas sentencias, del debate que han suscitado y de sus pros y contras.
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