Experimental research on electric propulsion. Note 5: Experimental study of a magnetic field stabilized arc-jet

The possibility of using an electric arc under the influence of a magnetic field in ambient air to transform the heat energy of the working fluid arc into the kinetic energy of the jet was investigated. A convergent-divergent type nozzle was used. Variation of specific thrust and chamber pressure are discussed. Nitrogen was the propellant used

Experimental research on electric propulsion. Note 7: Analysis of the performance of an arc-jet driven by means of hydrogen and nitrogen

Experiments which use a new type of arc-jet, characterized by composite electromagnetic and vortex stabilization and propelled by hydrogen and nitrogen in turn are described. The electrical characteristics of the arc and the loss of heat through the electrodes is emphasized

Experimental research on electrical propulsion. Note 2: Experimental research on a plasma jet with vortex type stabilization for propulsion

Results of experimental electric propulsion research are presented. A plasma generator, with an arc stabilized by an air vortex is examined. The heat transfer efficiency between arc and fluid environment at a varying current and flow rate is discussed

Experimental research on electrical propulsion

This paper describes work on arcs rotating in a magnetic field. Particular care was taken about the design of the electrodes in order to achieve long-time operation. Successful performance tests were carried out

Translation, Cross-Cultural Adaptation, and Preliminary Validation of the Transsexual Voice Questionnaire for Male-to-Female Transsexuals (I-TVQ MtF) Into Italian

Summary: Objective.To perform a cross-cultural adaptation into Italian and to analyse reliability and valid-ity of the Transsexual Voice Questionnaire for male-to-female transsexuals (I-TVQMtF).Study Design.Cross-sectional nonrandomized survey study.Methods.For item-generation, a cross-cultural adaptation and translation process was performed followingstandard guidelines. Transgender women were consecutively recruited and asked tofill out the I-TVQMtFand aform on social, demographic and transition-related variables. Firstly, data collected from participants were usedto perform confirmatory factor analysis, and to evaluate internal consistency and test-retest reliability Subse-quently, convergent validity was evaluated comparing I-TVQMtFtotal scores with the two extra items addressingself-perception (SPVF) and aspiration (AVF) of voice femininity. To evaluate convergent validity, scores of theItalian version of the Voice Handicap Index were considered for comparisons. A correlation analysis was per-formed to verify potential association between I-TVQMtFscores and social, demographic and transition-relatedvariables.Results.Confirmatory factor analysis demonstrated that a two-factor modelfits data better than the unidimen-sional one. Both internal consistency and test retest reliability of the I-TVQMtFwere satisfactory. Negative corre-lations were highlighted between I-TVQMtFscores on one side and self-perception vocal functioning andaspiration vocal functioning on the other. Positive correlations between I-TVQMtFand Italian version of theVoice Handicap Index scores were also found. Finally, negative correlations were demonstrated between I-TVQMtFscores and time spent living in the female role.Conclusion.The I-TVQMtFappears to be a reliable and valid instrument for the assessment of voice-relatedquality of life in transgender women

Assessing effectiveness of Komagataeibacter strains for producing surface-microstructured cellulose via guided assembly-based biolithography.

In this study, a medical device made of surface microstructured bacterial cellulose was produced using cellulose‑producing acetic acid bacteria wild‑type strains in combination with guided assembly‑based biolithography. The medical device aims at interfering with the cell’s focal adhesion establishment and maturation around implantable devices placed in soft tissues by the symmetrical array on its surface. A total of 25 Komagataeibacter strains was evaluated over a three‑step selection. In the first step, the ability of strains to produce a suitable bacterial cellulose layer with high production yield was examined, then nine strains, with a uniform and smooth layer of bacterial cellulose, were cultured in a custom‑made silicone bioreactor and finally the characteristics of the symmetrical array of topographic features on the surface were analysed. Selected strains showed high inter and intra species variability in bacterial cellulose production. The devices obtained by K2G30, K1G4, DSM 46590 (Komagataeibacter xylinus), K2A8 (Komagataeibacter sp.) and DSM 15973T (Komagataeibacter sucrofermentas) strains were pouched‑formed with hexagonal surface pattern required for reducing the formation of fibrotic tissue around devices, once they are implanted in soft tissues. Our findings revealed the effectiveness of the selected Komagataeibacter wild‑type strains in producing surface microstructured bacterial cellulose pouches for making biomedical devices