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Traveling wave structures for lossless ion manipulation (TW-SLIM) has proven a valuable tool for the separation and study of gas-phase ions. Unfortunately, many of the traditional components of TW-SLIM experiments manifest practical and financial barriers to the technique's broad implementation. To this end, a series of technological innovations and methodologies are presented which enable for simplified SLIM experimentation and more rapid TW-SLIM prototyping. In addition to the use of multiple independent board sets that comprise the present SLIM system, we introduce a low-cost, multifunctional traveling wave generator to produce TW within the TW-SLIM. This square-wave producing unit proved effective in realizing TW-SLIM separations compared to traditional approaches. Maintaining a focus on lowering barriers to implementation, the present set of experiments explores the use of on-board injection (OBI) methods, which offer potential alternatives to ion funnel traps. These OBI techniques proved feasible and the ability of this simplified TW-SLIM platform to enhance ion accumulation was established. Further experimentation regarding ion accumulation revealed a complexity to ion accumulation within TW-SLIM that has yet to be expounded upon. Lastly, the ability of the presented TW-SLIM platform to store ions for extended periods (1 s) without significant loss (<10%) was demonstrated. The aforementioned experiments clearly establish the efficacy of a simplified TW-SLIM platform which promises to expand adoption and experimentation of the technique.
(Copyright © 2022 Elsevier B.V. All rights reserved.)
This case report describes the successful orthodontic treatment of an 11-year-old girl with skeletal Class II malocclusion and congenitally missing mandibular second premolars. To resolve her upper lip protrusion and restore the missing mandibular premolars, extraction of the maxillary first premolars and subsequent autotransplantation of the extracted premolars onto the site of the missing mandibular second premolars were performed. To ensure the success of the autotransplantation and subsequent orthodontic treatment, an orthodontic force was preapplied on the donor teeth, and the recipient sockets were prepared with the aid of replica teeth. Thereafter, comprehensive orthodontic treatment was performed to close the extraction space in the maxilla and align the mandibular dentition, including the transplants. The patient achieved a functional occlusion with an improved facial profile. Results of the orthodontic treatment and autotransplantation were stable during the 5-year follow-up. On the basis of this report, a management protocol for a biomechanically enhanced autotransplantation procedure was suggested. This approach would enable an effective treatment procedure, thereby increasing the usefulness of autotransplantation.
(Copyright © 2022 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)
Gene Library, Protein Biosynthesis, Synthetic Biology, High-Throughput Screening Assays, and Microfluidics methods
Engineering regulatory parts for improved performance in genetic programs has played a pivotal role in the development of the synthetic biology cell programming toolbox. Here, we report the development of a novel high-throughput platform for regulatory part prototyping and analysis that leverages the advantages of engineered DNA libraries, cell-free protein synthesis (CFPS), high-throughput emulsion droplet microfluidics, standard flow sorting adapted to screen droplet reactions, and next-generation sequencing (NGS). With this integrated platform, we screened the activity of millions of genetic parts within hours, followed by NGS retrieval of the improved designs. This in vitro platform is particularly valuable for engineering regulatory parts of nonmodel organisms, where in vivo high-throughput screening methods are not readily available. The platform can be extended to multipart screening of complete genetic programs to optimize yield and stability.
Purpose: Virtual reality (VR) can provide an added value for diagnosis and/or intervention planning. Several VR software implementations have been proposed but they are often application dependent. Previous attempts for a more generic solution incorporating VR in medical prototyping software (MeVisLab) were still lacking functionality precluding easy and flexible development.
Methods: We propose an alternative solution that uses rendering to a graphical processing unit (GPU) texture to enable rendering arbitrary Open Inventor scenes in a VR context. It facilitates flexible development of user interaction and rendering of more complex scenes involving multiple objects. We tested the platform in planning a transcatheter cardiac stent placement procedure. Results: This approach proved to enable development of a particular implementation that facilitates planning of percutaneous treatment of a sinus venosus atrial septal defect. The implementation showed it is intuitive to plan and verify the procedure using VR. Conclusion: An alternative implementation for linking OpenVR with MeVisLab is provided that offers more flexible development of VR prototypes which can facilitate further clinical validation of this technology in various medical disciplines. (© 2022. CARS.)
Autotrophic Processes, Fermentation, Oxidation-Reduction, Carbon Cycle, and Escherichia coli metabolism
Carbon-negative synthesis of biochemical products has the potential to mitigate global CO 2 emissions. An attractive route to do this is the reverse β-oxidation (r-BOX) pathway coupled to the Wood-Ljungdahl pathway. Here, we optimize and implement r-BOX for the synthesis of C4-C6 acids and alcohols. With a high-throughput in vitro prototyping workflow, we screen 762 unique pathway combinations using cell-free extracts tailored for r-BOX to identify enzyme sets for enhanced product selectivity. Implementation of these pathways into Escherichia coli generates designer strains for the selective production of butanoic acid (4.9 ± 0.1 gL -1 ), as well as hexanoic acid (3.06 ± 0.03 gL -1 ) and 1-hexanol (1.0 ± 0.1 gL -1 ) at the best performance reported to date in this bacterium. We also generate Clostridium autoethanogenum strains able to produce 1-hexanol from syngas, achieving a titer of 0.26 gL -1 in a 1.5 L continuous fermentation. Our strategy enables optimization of r-BOX derived products for biomanufacturing and industrial biotechnology.
(© 2022. The Author(s).)
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