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Frederik Goethals Elisabeth Levrau Els De Canck Mikhail R. Baklanov Christophe Detavernier Isabel Van Driessche Pascal Van Der Voort 《Materials》2013,6(2):570-579
To use mesoporous silicas as low-k materials, the pore entrances must be really small to avoid diffusion of metals that can increase the dielectric constant of the low-k dielectric. In this paper we present a new method to narrow the pores of mesoporous materials through grafting of a cyclic-bridged organosilane precursor. As mesoporous material, the well-studied MCM-41 powder was selected to allow an easy characterization of the grafting reactions. Firstly, the successful grafting of the cyclic-bridged organosilane precursor on MCM-41 is presented. Secondly, it is demonstrated that pore narrowing can be obtained without losing porosity by removing the porogen template after grafting. The remaining silanols in the pores can then be end-capped with hexamethyl disilazane (HMDS) to make the material completely hydrophobic. Finally, we applied the pore narrowing method on organosilica films to prove that this method is also successful on existing low-k materials. 相似文献
113.
Isabel Cristina Celerino de Moraes Porto Flávio Henrique Baggio de Aguiar William Cunha Brandt Priscila Christiane Susy Liporoni 《Journal of dentistry》2013,41(8):732-739
ObjectivesThis study measured the degree of conversion (DC), sorption, solubility and microhardness of methacrylate (Filtek Z250 and Filtek Z350XT) and silorane-based composites (Filtek P90).MethodsDC was measured using near infrared spectroscopy immediately and 24 h after the photoactivation. Sorption and solubility measurements were performed after 24 h, 4 weeks and 12 weeks of storage in water. Knoop microhardness was measured after 24 h and after thermal cycling. The data were statistically analyzed using ANOVA followed by Tukey's, Tamhane or paired t-tests (α = 0.05).ResultsThe DC for P90 (37.22 ± 1.46) was significantly lower than the Z250 (71.44 ± 1.66) and Z350 (71.76 ± 2.84). Water sorption was highest in the Z250 and lowest in the P90. All the tested composites exhibited similar values after 24 h of immersion, and no significant differences were observed. No significant differences were observed between the solubilities of the P90 composite (12 weeks) and the Z250 or Z350 composites (4 weeks). KHN values were less elevated for the P90 composite and similar for the Z250 and Z350 composites. An effect of thermal cycling on KHN values was observed for all the composites (p < 0.001).ConclusionsSilorane produced the lowest DC and KHN values and exhibited lower water sorption and solubility compared to methacrylate-based composites. These differences suggest that silorane composites exhibit better hydrolytic stability after 3 months of water immersion compared to conventional methacrylate-based composites.Clinical significanceSilorane had higher hydrolytic stability after 3 months of water immersion than the methacrylate-based resins, despite the lower values of DC and KHN recorded. 相似文献
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Isabel García-López Susana Santiago-Pérez Julio Peñarrocha-Teres Antonio J. del Palacio Javier Gavilan 《Acta otorrinolaringologica espanola》2012,63(6):458-464
Introduction and objectivesLaryngeal electromyography, together with clinical evaluation, is a valuable tool in voice disorder management. It assesses the integrity of laryngeal nerves and muscles, contributing to the diagnosis of many diseases, especially laryngeal movement disorders. Our purpose was to describe the experience of the first Spanish series with laryngeal electromyography in evaluating voice disorders.MethodsA prospective study was designed to evaluate laryngeal movement disorders with laryngeal electromyography. Both the cricothyroid and thyroarytenoid muscles were tested routinely and, in some cases, the posterior cricoarytenoid muscle. The laryngeal electromyography technique and result interpretation were performed by a laryngologist and a neurophysiologist.ResultsWe included 110 patients, with the most common symptom being dysphonia. Laryngeal electromyography was performed in 85% of cases. Primary diagnosis before electromyography was laryngeal immobility. Positive predictive value for diagnosis in cases of paralysis was 88%.ConclusionsLaryngeal electromyography is a useful adjunct, together with clinical evaluation, for diagnosis and management of motion abnormalities in the larynx in patients who present with dysphonia. 相似文献
116.
José Elías García-Sánchez M. Inmaculada García-García Fernando García-Garrote Isabel Sánchez-Romero 《Enfermedades infecciosas y microbiología clínica》2013
Intra-abdominal infections represent a large and wide group of diseases which include intra- and retro-peritoneal infections. Some of them could be defined as uncomplicated, where the infectious process is limited to the organ or tissue of origin (appendicitis, diverticulitis, cholecystitis…). Complications occur when the infection spreads to the peritoneum, triggering localised peritonitis and abdominal abscesses. 相似文献
117.
María Pérez-Crespo José Manuel Ramos-Rincón María Pilar Albares-Tendero Isabel Betlloch-Mas 《Journal of immigrant and minority health / Center for Minority Public Health》2016,18(1):16-20
Over the past 10 years Spain has become an important immigrant receiver country as the proximity with Africa and the cultural facilities with Latino-American countries have made of Spain a very attractive place to settle down for immigrants. From 1st January 2007 to 31st December 2007, all the pediatric patients visits (0–14 years old) seen in the units of the Dermatology Section of the University General Hospital of Alicante (Spain) were prospectively recorded. During the study period 3,108 visits were recorded. Of these, 447 (14.3 %) were generated by immigrant children, 243 (54.3 %) being episodes requested by 167 Latin American patients. Latin children consulted mainly in the outpatient clinic, like Spanish children. The most frequent type of dermatoses in these patients was eczema/atopic dermatitis. Infectious dermatitis showed no differences between them and Spaniards, but scabies was six times more frequent in the formers. 相似文献
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Pedro Christian Aravena Stephania Pilar Sandoval Felipe Eduardo Pizarro María Isabel Simpson Nicolás Castro-Adams Guillaume Serandour Cristian Rosas 《Journal of oral and maxillofacial surgery》2021,79(3):575-584
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