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The injection performance of a small volume of needle-free injection (up to 0.3 mL) has proven to be controllable and satisfactory in transdermal drug delivery. However, no comprehensive research on the behavior of larger volume injections with different requirements for clinical applications exists. This study aims to present the penetration characteristics of larger volume injections, including dynamic properties, dispersion pattern, and percent delivery. The researchers conduct impact and injection experiments with injection volumes from 0.1–1.0 mL, driving pressures of 0.5–1.75 MPa, and orifice diameters of 0.17–0.5 mm. This study uses high-speed photography and impact experiments to capture the dynamic properties of the liquid jet. The researchers observe the dispersion patterns of liquid penetration into the gels in the gel injection experiments and investigate the percentages of liquid delivered to the skin tissues in porcine tissues injection experiments. Moreover, this study uses the response surface methodology (RSM) to analyze the interactive effect between various injection parameters on the injection performance. Results describe the differences in penetration performance between larger volume injections and small volume injections, and the critical volume of the mentioned injections is approximately 0.6 mL. [ABSTRACT FROM AUTHOR]

Needle-free injection is an alternative strategy to conventional needle injection in the field of drug delivery. This approach offers a number of advantages, especially in reducing complaints of needle phobia and avoiding the occurrence of accidental needle stick injuries. The ejection volume and orifice diameter are inherently important in determining the injection depth and percent delivery. In this study, we investigate the dispersion pattern of liquid penetration into gels and porcine tissues using a needle-free injector with ejection volumes of 0.05 to 0.35 mL and orifice diameters of 0.17 to 0.50 mm. In addition, the influence of the two parameters is analyzed quantitatively on the dispersion pattern through impact experiments and injection experiments. Furthermore, an equation of the jet power calculated by the ejection volume and orifice diameter is proposed to describe the delivery fraction of the injection experiments. Controls of the ejection volume and orifice diameter are demonstrated to help achieve a more effective injection process and a better injection experience. [ABSTRACT FROM AUTHOR]

The disk-jet symbiosis is a fundamental problem in our understanding of the Active Galactic Nuclei (AGN). We explore the relation between the Doppler factors δ of the jet of blazars and their broad line region luminosity L. Since different methods measuring δ might differ substantially, we use data obtained from 3 independent methods and compile 3 samples of sources for each of them, respectively. Two samples consist of blazars, that is, Flat Spectrum Radio Quasars (FSRQs) and BL Lacertae objects (BL Lacs), and the other consists of BL Lacs. δ is one of the most important jet properties and L is thought to be the proxy of the accretion power. Correlation analysis to these samples shows that there exists a significant correlation between δ and L, which supports the idea that the jet powering process is closely linked with the accretion process and provides new evidence for disk-jet connection. Furthermore, the results are consistent with the idea that the Blandford-Znajek mechanism is sufficient for BL Lacs and a hybrid model is needed for FSRQs. [ABSTRACT FROM AUTHOR]