1000 resultados para 352(815.2)


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This paper proposes a response surface methodology to evaluate the influence of the particle size and temperature as variables and their interaction on the sulfation process using two Brazilian limestones, a calcite (ICB) and a dolomite (DP). Experiments were performed according to an experimental design [central composite rotatable design (CCRD)] carried out on a thermogravimetric balance and a nitrogen adsorption porosimeter. In the SO 2 sorption process, DP was shown to be more efficient than ICB. The best results for both limestones in relation to conversion and Brunauer-Emmett-Teller (BET) surface area were obtained under central point conditions (545 μm and 850 C for DP and 274 μm and 815 C for ICB). The optimal values for conversion were 52% for DP and 37% for ICB. For BET surface area, the optimal values were 35 m2 g-1 for DP and 45 m2 g-1 for ICB. A relationship between conversion and pore size distribution has been established. The experiments that showed higher conversions also exhibited more pores in the region between 20 and 150 Å and larger BET surface area, indicating that the amount of smaller pores may be an important factor in the reactivity of limestones. © 2013 American Chemical Society.

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The peripheral giant cell granuloma (GPCG) is defined as a benign disorder of uncertain etiopathogenesis, and proliferative reaction of the fibrous connective tissue or the periosteum, which is characterized histologically by the presence of multinucleated giant cells. The purpose of this study is report a case of GPCG in a white women, with 56 years old, presenting nodule bleeding to the touch, red and white with small ulcerated areas, defined limits, resilient consistency, pedicled base with 2.0 cm diameter, asymptomatic, involving the permanent lower left third molar, that it was presented with mobility. Radiographically there was significant bone loss in this tooth region, whose initial diagnosis was pyogenic granuloma. The definitive diagnosis was obtained after excisional biopsy in which microscopic examination it was identified e presence of multinucleated giant cells. The clinical postoperative presented favorable cicatricial repairing of the operated area without recurrence after two years of monitoring.

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Background/Aims: beta(2)-adrenoceptor (beta(2)-AR) activation induces smooth muscle relaxation and endothelium-derived nitric oxide (NO) release. However, whether endogenous basal beta(2)-AR activity controls vascular redox status and NO bioavailability is unclear. Thus, we aimed to evaluate vascular reactivity in mice lacking functional beta(2)-AR (beta 2KO), focusing on the role of NO and superoxide anion. Methods and Results: Isolated thoracic aortas from beta 2KO and wild-type mice (WT) were studied. beta 2KO aortas exhibited an enhanced contractile response to phenylephrine compared to WT. Endothelial removal and L-NAME incubation increased phenylephrine-induced contraction, abolishing the differences between beta 2KO and WT mice. Basal NO availability was reduced in aortas from beta 2KO mice. Incubation of beta 2KO aortas with superoxide dismutase or NADPH inhibitor apocynin restored the enhanced contractile response to phenylephrine to WT levels. beta 2KO aortas exhibited oxidative stress detected by enhanced dihydroethidium fluorescence, which was normalized by apocynin. Protein expression of eNOS was reduced, while p47(phox) expression was enhanced in beta 2KO aortas. Conclusions: The present results demonstrate for the first time that enhanced NADPH-derived superoxide anion production is associated with reduced NO bioavailability in aortas of beta 2KO mice. This study extends the knowledge of the relevance of the endogenous activity of beta(2)-AR to the maintenance of the vascular physiology. Copyright (C) 2012 S. Karger AG, Basel

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Der Kurzkommentar zur ZPO erlaubt in handlicher Form einen schnellen Zugriff auf das schweizerische Zivilverfahrensrecht. In knapper und übersichtlicher Darstellung werden die wesentlichen Fragestellungen analysiert und die wichtigsten Argumente und Gegenargumente zu umstrittenen Punkten für die Praxis verfügbar gemacht. Zur Neuauflage Für die 2. Auflage wurde der Kommentar umfassend aktualisiert und überarbei- tet. Die Nutzerinnen und Nutzer erhalten damit ein kompaktes Arbeitsmittel auf dem Stand Frühjahr 2013. Berücksichtigt werden insbesondere: − das neue Erwachsenenschutzrecht − die am 1.5.2013 in Kraft getretenen neuen Protokollierungsvorschriften für die Zeugeneinvernahme − die inzwischen schon zahlreichen Weichenstellungen in der Rechtsprechung zur schweizerischen Zivilprozessordnung − die seit 2011 erschienene praxisrelevante neue Literatur (inkl. Neuauflage des BSK ZPO

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Berichtigungen zu einem Artikel im "Beobachter", Johann Wolfgang von Goethe, Johann Gerhard Christian Thomas, Johann Jakob von Willemer, Marianne Willemer, Samuel Zirndorfer, Der Fiacre (Zeitschrift), Zensor Thomas(1848), Thomas, Redakteur der Ober-Postamts-Zeitung

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The ice cover of the Arctic Ocean has been changing dramatically in the last decades and the consequences for the sea-ice associated ecosystem remain difficult to assess. Algal aggregates underneath sea ice have been described sporadically but the frequency and distribution of their occurrence is not well quantified. We used upward looking images obtained by a remotely operated vehicle (ROV) to derive estimates of ice algal aggregate biomass and to investigate their spatial distribution. During the IceArc expedition (ARK-XXVII/3) of RV Polarstern in late summer 2012, different types of algal aggregates were observed floating underneath various ice types in the Central Arctic basins. Our results show that the floe scale distribution of algal aggregates in late summer is very patchy and determined by the topography of the ice underside, with aggregates collecting in dome shaped structures and at the edges of pressure ridges. The buoyancy of the aggregates was also evident from analysis of the aggregate size distribution. Different approaches used to estimate aggregate biomass yield a wide range of results. This highlights that special care must be taken when upscaling observations and comparing results from surveys conducted using different methods or on different spatial scales.

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Radiolaria were studied in 19 manganese nodules raised from the bottom. The nodules occurred mainly on the surface of thin Quaternary sediments covering Tertiary deposits of various ages (Middle Eocene to Early Miocene). Radiolaria in nodule cores and in inner and surface layers were studied. We found 85 radiolaria species and groups of species. Usually 1-4 to 6-19 radiolaria species were detected in each of the samples. Species belonging to Middle Eocene, Late Miocene to Early Oligocene, and Oligocene to Early Miocene were found. Rare Neogene species were revealed only in fractured surface layers. Age of the nodules is mainly Oligocene. Seismic waves cause sediment vibration, loosening disintegration, and removal of suspension by bottom currents. The vibration effect causes ancient nodules to float up to the surface of Quaternary sediment. This hypothesis suggests the reason for characteristics of the Clarion-Clipperton zone: regional stratigraphic hiatus, accumulation of residual fields of nodules, and the ''floating up'' of nodules to the surface of the Quaternary sediments.

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Fil: Napoli, Magdalena M.. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación. Instituto de Investigaciones en Humanidades y Ciencias Sociales (UNLP-CONICET); Argentina.