21 research outputs found

    Synthesis of ZnO nanoparticles by flame spray pyrolysis and characterisation protocol

    No full text
    There is uncertainty concerning the potential toxicity of zinc oxide (ZnO) nanoparticles, which may be attributed in part to a lack of understanding with regard to the physiochemical properties of the nanoparticles used in toxicological investigations. This paper reports the synthesis of a ZnO nanopowder by flame spray pyrolysis and demonstrates that the typically employed characterisation techniques such as specific surface area measurement and X-ray diffraction provide insufficient information on the sample, especially if it is intended for use in toxicity studies. Instead, a more elaborate characterisation protocol is proposed that includes particle morphology as well as detailed compositional analysis of the nanoparticle surface. Detailed transmission electron microscopy analysis illustrated the polydispersity within the sample: particles were elongated in the c-crystallographic direction, with average Ferret length ∼23 nm and Ferret width ∼14 nm. Dynamic light scattering (0.1 w/v% in deionised water, pH 7.4) revealed the particles were agglomerated with a modal secondary particle size of ∼1.5 μm. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy indicated the presence of carbonate and hydroxide impurities on the surface of the ZnO nanoparticles and an increase of such impurities was observed as the sample was aged, which might influence the nanoparticle dissolution and/or cellular uptake behaviour. These data will be utilised, in order to facilitate the interpretation and understanding of results from toxicological investigations using in vitro cell lines

    Investing in critical and cultural theory while learning how to develop a studio practice that allows a free play of opposites, restricts formulas, and encourages students to experiment widely

    No full text
    This Panel proposes to provide Surprising and Practical solutions, as well as wild possibilities for Studio Courses in which students resist reading, thinking, working within a context and generally want to avoid subject driven experience. Two Artists, a Scholar and a Theory Guy explain what decades of experimental teaching, investigative research, serious considerations and soulful humor, has revealed. The problem being; how too much intellectualizing destroys the intuitive process, and how a lack of knowledge and study weakens our students’ ability to think, deprives them of a dialog with their peers, and leaves them blank as well as lost regarding contemporary thought and Issues

    Systems and methods for respiratory event detection

    No full text
    The present invention is directed to improved systems and methods for processing respiratory signals derived generally from respiratory plethysmography, and especially from respiratory inductive plethysmographic sensors mounted on a garment for ambulatory recording. The systems and methods provide improved signal filtering for artifact rejection, improved calibration of sensor data to produce outputs indicative of lung volumes. Further, this invention provides improved systems and methods directed to processing lung volume signals, however measured or derived, to provide improved determination of respiratory parameters and improved recognition of selected respiratory events

    Safety and Availability of Dapivirine (TMC120) Delivered from an Intravaginal Ring

    No full text
    Vaginal delivery of 200 mg or 25 mg dapivirine from intravaginal rings (IVRs) was evaluated over a 7-day period in two phase 1 safety trials (IPM001 and IPM008, respectively) in a total of 25 healthy women 19 to 46 years of age. The IVR was generally safe and well tolerated with similar adverse events observed in the placebo and dapivirine groups. Across both studies, dapivirine concentrations in vaginal fluids measured at the introitus, cervix, and ring area were within the mean range of 0.7-7.1 mg/ml. Mean dapivirine concentrations in vaginal and cervical tissues on day 7 were 0.3-0.7 mg/g in IPM001 and 1.5-3.5 mg/g in IPM008. Mean plasma concentrations of dapivirine were 1000x the EC50 against wild-type HIV-1 (LAI) in MT4 cells suggesting that IVR delivery of microbicides is a viable option meriting further study
    corecore