Establishment of the Carrot-Made LTB-Syn Antigen Cell Line in Shake Flask and Airlift Bioreactor Cultures

Carrot (Daucus carota) cells have been used to effectively manufacture recombinant biopharmaceuticals such as cytokines, vaccines, and antibodies. We generated the carrot cell line Z4, genetically modified to produce the LTB-Syn antigen, which is a fusion protein proposed for immunotherapy against synucleinopathies. In this work, the Z4 cell suspension line was cultivated to produce the LTB-Syn protein in a 250 mL shake flask and 2 L airlift bioreactor cultures grown for 45 and 30 days, respectively. Maximum biomass was obtained on day 15 in both the airlift bioreactor (35.00 ± 0.04 g/L DW) and shake flasks (17.00 ± 0.04 g/L DW). In the bioreactor, the highest LTB-Syn protein yield (1.52 ± 0.03 µg/g FW) was obtained on day 15; while the same occurred on day 18 for shake flasks (0.92 ± 0.02 µg/g FW). LTB-Syn protein levels were analyzed by GM1-ELISA and western blot. PCR analysis confirmed the presence of the transgene in the Z4 line. The obtained data demonstrate that the carrot Z4 cell suspension line grown in airlift bioreactors shows promise for a scale-up cultivation producing an oral LTB-Syn antigen.

Experimental Characterization of Drag Coefficient of an UAV Recovery Parachute

Parachute recovery systems are proved to be an efficient method to recovery and rescue unmanned aerial vehicles (UAV) as it follows most requirements of reliability and airworthiness in flights. Parachutes are key components of the recovery systems and the drag coefficient of parachutes plays a crucial role in evaluating parachute’s performance. The purpose of the research is to determine and compare the impact of some factors on aerodynamic drag force during the inflation of a parachute. The canopy’s shape (flat circular type and extended skirt 10% flat type), of the length of suspension lines (be in proportion to nominal diameter from 0.6 to 1.5) are considered. Measurement of the drag force of the parachute models is carried out in an open return wind tunnel. Experimental results show that flat circular canopy has a higher drag coefficient than extended skirt 10% flat model in the range of low speed from 3 to 6 m/s. However, when wind speed is greater than 6 m/s, the drag coefficients of both two parachute types are nearly 0.85. In terms of the suspension line, the longer length would significantly raise the coefficient of drag force.

Computational and Experimental Study for Reducing Forebody Wake Effect by Proper Designing of a Slit cut Square Parachute used for Sonobuoy Drop

This paper discusses the design of a square parachute based on classical approach, computational analysis and experimentation. This parachute will be used to drop directional sonobuoy on the sea to locate and classify the submarines. Design improvements are brought out by providing slits into a solid square canopy of parachute to bring in more stability and minimum drift during descend. Specifically, the effect of upstream sonobuoy, RANS model, suspension line length, canopy size and slit size in flow structure were considered. The predicted drag coefficients obtained from CFD for square canopy with slit-cuts compared with the results of wind tunnel experiment and found that the increase in the suspension-line length and/or of the surface area of the parachute canopy helps in better stability and results in the minimum drag loss.

Sequence diversity of two chloroplast genes: rps4 and tRNAGly (UCC), in the liverwort Marchantia polymorpha, an emerging plant model system

<p>The primary purpose of this study is to evaluate the sequence variation for two regions of chloroplast DNA in a collection of 27 taxonomically well-annotated clonal lines of <em>Marchantia polymorpha</em> sensu lato derived from European populations. We attempted to develop molecular markers so as to identify three taxa usually recognized as subspecies. We sequenced two regions: the <em>rps4</em> gene along with the <em>rps4-trnT</em> intergenic spacer and an intron of the tRNA^Gly (UCC) gene. Samples of <em>Marchantia paleacea</em> ssp. <em>diptera</em> from Japan were used for comparative purposes.</p><p>Three haplotypes (MA, MB, and MC) were identified for the species, and almost all sequence divergence between subspecies was found to occur at the level of 0.0023–0.0032 substitutions per site. The sequence divergence between <em>M. polymorpha</em> and <em>M. paleacea</em> was tenfold greater (0.0331–0.0340). We did not detect any differences between <em>M. paleacea</em> and homologous sequences from the reference chloroplast genome of <em>M. polymorpha</em> obtained from the GeneBank (NC_001319). It was confirmed that the cell suspension line A-18 used for the sequencing of the full chloroplast genome in 1986 was incorrectly taxonomically annotated.</p>