Intertwining relations for one-dimensional diffusions and application to functional inequalities

International audienceFollowing the recent work [13] fulfilled in the discrete case, we pro- vide in this paper new intertwining relations for semigroups of one-dimensional diffusions. Various applications of these results are investigated, among them the famous variational formula of the spectral gap derived by Chen and Wang [15] together with a new criterion ensuring that the logarithmic Sobolev inequality holds. We complete this work by revisiting some classical examples, for which new estimates on the optimal constants are derived

Preparation and Evaluation of Poly(Ethylene Glycol)–Poly(Lactide) Micelles as Nanocarriers for Oral Delivery of Cyclosporine A

A series of monomethoxy poly(ethylene glycol)–poly(lactide) (mPEG–PLA) diblock copolymers were designed according to polymer–drug compatibility and synthesized, and mPEG–PLA micelle was fabricated and used as a nanocarrier for solubilization and oral delivery of Cyclosporine A (CyA). CyA was efficiently encapsulated into the micelles with nanoscaled diameter ranged from 60 to 96 nm with a narrow size distribution. The favorable stabilities of CyA-loaded polymeric micelles were observed in simulated gastric and intestinal fluids. The in vitro drug release investigation demonstrated that drug release was retarded by polymeric micelles. The enhanced intestinal absorption of CyA-loaded polymeric micelles, which was comparable to the commercial formulation of CyA (Sandimmun Neoral®), was found. These suggested that polymeric micelles might be an effective nanocarrier for solubilization of poorly soluble CyA and further improving oral absorption of the drug

Positron interaction in polymers

A

Coupled first-principles and experimental positron annihilation study of defects in actinide mixed oxides

International audienc

Comparação dos efeitos de duas técnicas fisioterapêuticas respiratórias em parâmetros cardiorrespiratórios de lactentes com bronquiolite viral aguda Comparison of the effects that two different respiratory physical therapy techniques have on cardiorespiratory parameters in infants with acute viral bronchiolitis

OBJETIVO: Comparar os efeitos das técnicas de aumento do fluxo expiratório (AFE) e vibração associada à drenagem postural (DP) nos parâmetros cardiorrespiratórios de frequência cardíaca (FC), frequência respiratória (FR) e SpO2 de lactentes com bronquiolite viral aguda (BVA). MÉTODOS: Foram analisados lactentes com diagnóstico clínico e radiológico de BVA. A FC, FR e SpO2 foram registradas em quatro tempos: antes do procedimento e após 10, 30 e 60 min do término do procedimento. Os pacientes foram divididos em três grupos: submetido à AFE; submetido à vibração/DP; e controle. RESULTADOS: Foram incluídos no estudo 81 lactentes, 27 em cada grupo de estudo, com média de idade de 4,52 meses e peso médio de 6,56 kg. Na comparação por ANOVA, as médias da FR, FC e SpO2 nos grupos AFE e vibração/DP não apresentaram diferenças significantes em relação ao grupo controle (p > 0,05). Considerando somente os quatro tempos, houve queda significante dos valores médios de FR nos grupos AFE e vibração/DP em relação ao controle (p < 0,05). CONCLUSÕES: A aplicação de AFE e de vibração associada à DP não apresentou um benefício global na melhora dos parâmetros cardiorrespiratórios em lactentes com BVA. Quando analisados isoladamente no decorrer do tempo, a fisioterapia respiratória parece contribuir na diminuição da FR nesses pacientes.<br>OBJECTIVE: To compare the expiratory flow increase technique (EFIT) and vibration accompanied by postural drainage (PD) in terms of their effects on the heart rate (HR), respiratory rate (RR) and SpO2 of infants with acute viral bronchiolitis (AVB). METHODS: Infants with clinical and radiological diagnosis of AVB were analyzed. The HR, RR and SpO2 were registered at four time points: prior to the procedure; and at 10, 30 and 60 min after the procedure. The patients were divided into three groups: submitted to the EFIT; submitted to vibration/PD; and control. RESULTS: We included 81 infants, 27 per group, with a mean age of 4.52 years and a mean weight of 6.56 kg. Using ANOVA, we found that the EFIT and vibration/PD groups presented no significant differences in relation to the control group in terms of the mean values for HR, RR or SpO2 (p > 0.05). Considering only the four time points evaluated, the mean RR was significantly lower in the EFIT and vibration/PD groups than in the control group (p < 0.05). CONCLUSIONS: In terms of overall improvement of cardiorespiratory parameters, neither the EFIT nor vibration/PD provided any benefit to infants with BVA. However, over time, respiratory physical therapy seems to contribute to decreasing the RR in these patients