563 research outputs found
PATHOLOGICAL STUDY ON STAPHYLOCOCCUS XYLOSUS ISOLATED FROM PATIENTS WITH URINARY TRACT INFECTIONS
No full textRole of peptidoglycan in the pathogenesis of Staphylococcus saprophyticus in mice
No full textThe pathogenicity of S. saprophyticus was studied in mice. A group of white mice were injected transurethrally using a catheter with S. saprophyticus S67 cell suspension in a concentration reached 109 CFU/ml. concomitantly, the role of its peptidoglycan in the pathogenicity was studied by injecting another group of mice with 0.3 mg/0.2 ml of partially purified S. saprophyticus S67 peptidoglycan extract. After autopsy, kidneys and urinary bladder showed several histopathological changes both in cells and peptidoglycan injected mice, included: hydropic degeneration, glomerulus shrinkage, congestion of renal vessels, infiltration of inflammatory cells, and dekeratinization in urinary bladder
THE PATHOLOGICAL EFFECT OF PEPTIDOGLYCAN ON RATS’ LUNGS PART TWO: NON PATHOGENIC BACTERIA BACILLUS SUBTILIS
No full textSchulpstuw in het Spui ter vermindering van de verzilting van de Hollandsche IJssel
No full textAfsluiting van het Spui is één van de mogelijkheden die in het Vooronderzoek naar voren is gekomen om de verzilting van de Hollandsche IJssel te verminderen. Met name als de Bovenrijnafvoer tussen de 750 en 850 m3/s bedraagt, zal het afsluiten van het Spui effekt sorteren. Een Bovenrijnafvoer van 850 m3/s wordt gemiddeld 10 dagen per jaar onderschreden. In aanmerking komen een permanente afsluiting (b.v. een dijklichaam) of een tijdelijke afsluiting b.v. een beweegbaar afsluitmiddel), al of niet met schutsluis. Beschouwt men de afsluitfrekwentie, het scheepvaartverkeer en de kosten, dan slaat de balans door naar een tijdelijke afsluitmiddel zonder schutsluis. Uitvoering in den natte verdient uit praktische en financiële overwegingen sterk de voorkeur. Het vooronderzoek, deel I, is van de vakgroep Waterbouwkunde (Prof.ir. J.F. Agema). Het hoofdonderzoek, deel II, is gedaan bij de vakgroepen Constructieve Waterbouwkunde (Prof.ir. A Glerum) & Civiele Bedrijfskunde (Prof.ir. H.J. Wagenmaker).Hydraulic EngineeringCivil Engineering and Geoscience
Semantic metrics
No full textIn the context of the Semantic Web, many ontology-related operations, e.g. ontology ranking, segmentation, alignment, articulation, reuse, evaluation, can be boiled down to one fundamental operation: computing the similarity and?or dissimilarity among ontological entities, and in some cases among ontologies themselves. In this paper, we review standard metrics for computing distance measures and we propose a series of semantic metrics. We give a formal account of semantic metrics drawn from a variety of research disciplines, and enrich them with semantics based on standard Description Logic constructs. We argue that concept-based metrics can be aggregated to produce numeric distances at ontology-level and we speculate on the usability of our ideas through potential areas
Experimental research into the effect of freeboard on the stability of a crown wall on a rubble mound breakwater
No full textA crown wall is a gravity based L- shaped concrete structure on top of a rubble mound breakwater. Functions of a crown wall are: reduction of wave overtopping, enable transport on the breakwater and placement of pipelines on top of the flat surface. Marine contractor Van Oord was awarded to extend a breakwater with a crown wall on top, located in Romania. The design, already made by a local consultant, was reviewed by Van Oord, which led to the conclusion that the crown wall would be blown of the breakwater for that particular design in combination with the design wave conditions. Subsequently, physical scaled model tests were executed by Artelia in Grenoble, but, against all expectations the crown wall appeared to remain stable. Based on the contradiction between stability calculations and the outcome of the scaled model tests, the hypothesis arose that currently used wave load calculation methods lead to designs that seem to be conservative especially when freeboard, the vertical distance between the still water level and the base of the crown wall, increases. An experimental research is carried out in which the effect of freeboard is examined by varying water levels and wave conditions while geometrical properties of the structure remain constant. Tests are divided in three main subjects: pressure measurements, uplift stability and overall stability. Based on pressure measurements it is concluded that the mostly used design method PEDERSEN [1996] and its extended version of NØRGAARD et al. [2013], assume an upward pressure distribution which is too conservative in shape and distance over which pressure is exerted against the base of the crown wall. These methods assume a linear pressure distribution whereas this seems to be conservative based on test results since S-shaped and parabolic upward pressure distributions are found. Furthermore, it is assumed that upward pressure acts over the full length of the base whatever wave conditions and freeboard are. However, a relation is found which indicates that the effective length of the upward pressure actually depends on wave height and freeboard. Comparing the predicted vertical loads based on the methods of PEDERSEN [1996] and NØRGAARD et al. [2013] to the found vertical loads derived from uplift stability in this research, lead to substantial overpredictions when freeboard increases. Generated data with respect to critical weights confirms that the conventional methods of PEDERSEN [1996] and NØRGAARD et al. [2013] are too conservative in predicting overall stability with respect to sliding, especially when freeboard increases. However, by implementing the found relations for the effective length, especially NØRGAARD et al. [2013] become more reliable with respect to the found critical weights. Design guidelines are presented. It is advised to use these guidelines for prior design purposes in combination with the adapted method of NØRGAARD et al. [2013] in which a reduction coefficient for vertical loads must be taken into account. Since the range of application for the critical weight predictions is still small it is recommended to extend this range by varying more parameters in further research, which should make these guidelines generally better applicable.Civil Engineering and GeosciencesHydraulic Engineerin
Refugee shelters in Europe
No full textArchitecture and The Built EnvironmentArchitectural Engineering +Technolog
Witte steenkool in Nederland: Waarom niet?
No full textDoelstelling van dit onderzoek is geweest na te gaan in welke mate waterkracht bij de huidige energie-situatie (1980) al of niet toepasbaar (rendabel) is binnen Nederland. Wij hebben hier alleen kleine natuurlijke vervallen tot onze beschikking (H < ca. 20 m), waardoor reeds een afbakening zich aftekent: lage-vervalcentrales. Het uiteindelijke resultaat hiervan, de gunstigste optie binnen Nederland, is de staffelausbau Caberg- Born-Maasbracht-Heel, welke eventueel gefaseerd ingevoerd kan worden.Hydraulic EngineeringCivil Engineering and Geoscience
Al-Ḏajīra al-saniyya: una fuente relevante para el siglo XII en la Península Ibérica
No full textThe work al-Dhakhīra al-saniyya fī ta’rīkh al-dawla al-marīniyya records the history of the Marīnid dynasty, including a number of references to other Islamic regions like Egypt, Syria and al-Andalus. The authorship of this chronicle has not yet been solved. The aim of this paper is to provide the most relevant information on the issue. Alongside with other type of information concerning al-Andalus, this paper focuses on that which concerns the territory conquered by the Kingdom of Castile throughout the 13th century, and which so far has been mostly disregarded. It undoubtedly contributes to improve our knowledge of the period, especially as regards both the destiny of the conquered Muslim populations and the chronology of the conquest. We will also focus here on the political leaders of al-Andalus and Maghreb, their reactions towards the Christian conquests, ranging from utter resistance to conversion, and the importance this group attached to fighting the Christians, as a key factor of the political legitimacy of the Banū Marīn to guide the Islamic community, a point that greatly concerns the author of the present chronicle.La obra al-Ḏajīra al-saniyya fī ta’rīj aldawla al-marīniyya, que aborda la historia de los Banū Marīn, incluye una serie de noticias referentes a otras tierras de la Dār al-Islam, como Egipto, Siria o al-Andalus. La autoría de la misma no ha sido determinada, por lo que señalaremos las noticias más destacadas sobre este asunto. De la información que ofrece esta obra acerca de al-Andalus, este artículo se centra en el análisis de los fragmentos relativos a los territorios conquistados por Castilla durante el s. XIII, que no había sido aprovechada hasta el momento, y que contribuye a ampliar nuestro conocimiento acerca de este período histórico, muy especialmente por lo que respecta a la suerte que corrieron las poblaciones musulmanas y a la cronología de la conquista. Abordamos las actitudes adoptadas por los dirigentes políticos de al-Andalus y el Magreb, ante el avance de los cristianos, desde la resistencia hasta la conversión, y la importancia que este grupo concedió a las luchas contra los cristianos, que fueron un elemento de legitimación del poder político de los Banū Marīn, objetivo destacado del autor de la obra
Composieten van PMMA en Metaalvezels: bereidingswijze en mechanische en electrische eigenschappen
No full textTo make an isolating polymer conductive, it can be filled with metal particles. For the present investigation a combination of PMMA and aluminium flakes and fibres and PMMA with stainless steel fibers has been chosen. By filling PMMA with particles the tensile strength of the composite decreases to about the half of the value of PMMA, dependent on filler loading. The E-modulus increases with increasing filler loading. To increase the tensile strength, the metal particles were pretreated with a coupling agent, by which the adhesion of PMMA and the metal particles was improved. The results were dependent on the process of preparation of the composite. The E-modulus was mainly dependent on the filler loading. Because the long fibres were broken during the preparation of the composite, the expected improvement of the E-modulus by using longer fibres did not occur. During this study special attention was given to the influence of the A1-alloy related to the adhesion. Two Al-alloys were compared: an A1Mg-alloy: A15052 with a A1FeCo-alloy. The adhesion of the A1FeCo-alloy appears to be a little better then the adhesion of the Al-5052 alloy. There was no relation found between the alloy and the electrical conductivity of the composite. The electrical conductivity depends on the filler loading of the composite. The expected increase in electrical conductivity with lower filler loading and increase of aspect ratio of the fibres did not occur by flaw of the fibres by preparing the composite
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