High-throughput synthesis of CeO₂ nanoparticles for transparent nanocomposites repelling Pseudomonas aeruginosa biofilms

Preventing bacteria from adhering to material surfaces is an important technical problem and a major cause of infection. One of nature’s defense strategies against bacterial colonization is based on the biohalogenation of signal substances that interfere with bacterial communication. Biohalogenation is catalyzed by haloperoxidases, a class of metal-dependent enzymes whose activity can be mimicked by ceria nanoparticles. Transparent CeO(2)/polycarbonate surfaces that prevent adhesion, proliferation, and spread of Pseudomonas aeruginosa PA14 were manufactured. Large amounts of monodisperse CeO(2) nanoparticles were synthesized in segmented flow using a high-throughput microfluidic benchtop system using water/benzyl alcohol mixtures and oleylamine as capping agent. This reduced the reaction time for nanoceria by more than one order of magnitude compared to conventional batch methods. Ceria nanoparticles prepared by segmented flow showed high catalytic activity in halogenation reactions, which makes them highly efficient functional mimics of haloperoxidase enzymes. Haloperoxidases are used in nature by macroalgae to prevent formation of biofilms via halogenation of signaling compounds that interfere with bacterial cell–cell communication (“quorum sensing”). CeO(2)/polycarbonate nanocomposites were prepared by dip-coating plasma-treated polycarbonate panels in CeO(2) dispersions. These showed a reduction in bacterial biofilm formation of up to 85% using P. aeruginosa PA14 as model organism. Besides biofilm formation, also the production of the virulence factor pyocyanin in is under control of the entire quorum sensing systems P. aeruginosa. CeO(2)/PC showed a decrease of up to 55% in pyocyanin production, whereas no effect on bacterial growth in liquid culture was observed. This indicates that CeO(2) nanoparticles affect quorum sensing and inhibit biofilm formation in a non-biocidal manner

Druckentlastung in Systemen mit hoeherviskosen Fluessigkeiten Abschlussbericht

The purpose of the research project was to study pressure relief at the dome sid e of vessels in gas releasing and evaporating systems in the upper viscosity range. The viscosity of a liquid exerts an influence on fluid dynamics in the vessel and pressure relief system. Despite the pervasive use of high-range viscous liquids in chemical processes this parameter has hardly been examined until now. The results of the research project are expected to facilitate the design of reliable pressure relief systems for high-range viscous systems. (orig./HS)Ziel des durchgefuehrten Forschungsvorhabens ist die Untersuchung der behaelterdomseitigen Druckentlastung gasentloesender und siedender Systeme mit hoeherviskoser Fluessigkeitsphase. Die Fluessigkeitsviskositaet wirkt sich auf die Fluiddynamik im Behaelter und im Entlastungssytem aus. Obwohl in vielen chemischen Prozessen mit hoeherviskosen Fluessigkeiten umgegangen wird, ist der Einfluss dieses Parameters bislang kaum untersucht worden. Die Ergebnisse dieses Forschungsvorhabens sollen dazu dienen, Entlastungssysteme fuer Systeme mit hoeherviskosen Fluessigkeiten zuverlaessiger auslegen zu koennen. (orig./HS)Available from TIB Hannover: F93B1422+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Forschung und Technologie (BMFT), Bonn (Germany)DEGerman

A disciplina de Libras no contexto de formação acadêmica em Fonoaudiologia Libras discipline in speech language therapy academic context

OBJETIVO: analisar a inserção da disciplina de Libras em cursos nacionais de graduação em Fonoaudiologia, enfocando carga horária, período em que é ofertada, a natureza/estrutura da mesma; bem como, a avaliação de graduandos quanto à contribuição de tal disciplina na sua formação acadêmica e nas relações estabelecidas com sujeitos surdos. MÉTODO: foi aplicado um questionário a 240 acadêmicos de sete cursos de graduação em Fonoaudiologia, ofertados em Instituições de Ensino nacionais. Para tanto, adotou-se como critério de inclusão, acadêmicos que já tivessem cumprido a carga horária total da disciplina de Libras. O questionário foi respondido por escrito nas dependências dos cursos. Os resultados, analisados quantitativamente, foram organizados e apresentados em tabelas de frequências absolutas e relativas. RESULTADOS: os achados demonstram que se por um lado dentre os acadêmicos predomina a visão de que a carga horária destinada à referida disciplina é insuficiente, por outro existe uma conscientização por parte dos mesmos quanto à importância e à necessidade da formação em Libras. CONCLUSÃO: a partir de tal estudo pode-se evidenciar a necessidade do aprofundamento de discussões no contexto fonoaudiológico acerca da formação acadêmica voltada a Libras, bem como a definição de critérios e parâmetros que garantam um ensino de qualidade em torno de tal conteúdo. Esse estudo aponta para a necessidade do implemento de pesquisas que ofereçam elementos para o avanço na formação acadêmica fonoaudiológica voltada ao referido conteúdo, bem como, contribuam para a avanço de práticas fonoaudiológicas bilíngues, clínicas e educacionais, dirigidas a sujeitos surdos.<br>PURPOSE: to analyze the insertion of a sign language discipline in national speech language therapy courses, approaching the number of hours spent with the discipline, the period when its offered, the structure nature, and the students evaluation about this discipline’s contribution for their academic formation. METHOD: a questionnaire was applied to 240 speech language therapy students from seven national speech therapy graduation courses. For that, the insertion criterion adopted was that the students should have already concluded the discipline. The questionnaire was answered, in writing, inside their facilities. The results were quantitative and will be submitted in tables with absolute frequencies. RESULTS: the results show that the students believe that the number of hours spent with the discipline is insufficient; in addition, they are aware about the importance and the need of the sign language discipline. CONCLUSION: this study demonstrates that the discussion about sign language in speech language therapy courses must be broader. The definition of criteria and parameters must also be discussed in order assure learning quality in those contents. The study also shows the need for more research that offers allowance to the advance in the speech language therapy graduation courses in those contents and that also contributes to an advance in bilingual speech therapy clinical, educational and practical needs directed towards the deaf individuals