Portable Cathode-Air Vapor-Feed Electrochemical Medical Oxygen Concentrator (OC)

Missions on the International Space Station and future space exploration will present significant challenges to crew health care capabilities, particularly in the efficient utilization of onboard oxygen resources. Exploration vehicles will require lightweight, compact, and portable oxygen concentrators that can provide medical-grade oxygen from the ambient cabin air. Current pressure-swing adsorption OCs are heavy and bulky, require significant start-up periods, operate in narrow temperature ranges, and require a liquid water feed. Lynntech, Inc., has developed an electrochemical OC that operates with a cathode-air vapor feed, eliminating the need for a bulky onboard water supply. Lynntech's OC is smaller and lighter than conventional pressure-swing OCs, is capable of instant start-up, and operates over a temperature range of 5-80 C. Accomplished through a unique nanocomposite proton exchange membrane and catalyst technology, the unit delivers 4 standard liters per minute of humidified oxygen at 60 percent concentration. The technology enables both ambient-pressure operating devices for portable applications and pressurized (up to 3,600 psi) OC devices for stationary applications

Modeling of D/C motor driven synthetic jet acutators for flow separation control

The objective of this research is to present a theoretical study of the compressibility effects on the performance of an electric D/C motor driven synthetic jet actuator for flow separation control. Hot wire anemometer experiments were conducted to validate the jet exit velocities predicted by the theoretical model. The optimal jet exit velocity required to achieve maximum flow reattachment at reasonable blowing momentum coefficients is predicted. A dynamic electro-acoustic model of the D/C motor driven actuator is developed to accurately predict its performance and efficiency. This model should help formulate a feedback optimal control strategy for real-time flow control using an array of actuators. This model is validated by comparing with hot wire anemometer experiments conducted under similar conditions. The effects of geometric parameters like the slot width, slot geometry, and cavity volume on the performance of the actuator are also tested using this model

A microfluidic device for continuous capture and concentration of pathogens from water

A microfluidic device, based on electrophoretic transport and electrostatic trapping of charged particles, has been developed for continuous capture and concentration of microorganisms from water. A generic design, utilizing mobility and zeta potential measurements of various microorganisms exposed to different environmental conditions and physiological states, was employed. Water and buffer samples at pH values ranging from 5.2–7.0 were seeded with bacteria (E. coli, Salmonella, and Pseudomonas) and viruses (MS-2 and Echovirus). Negative control and capture experiments were performed simultaneously using two identical devices. Both culture based methods and real-time PCR analysis were utilized to characterize the capture efficiency as a function of time, flowrate, and applied electric field. Based on differences between the capture and negative control data, capture efficiencies of 90% to 99% are reported for E. coli, Salmonella, Pseudomonas, and MS-2, while the capture efficiency for Echovirus was around 75%. Overall, the device exhibits 16.67 fold sample volume reduction within an hour at 6 mL/hr. This results in a concentration factor of 15 at 90% capture efficiency. Direct quantification of capture on the anode of the prototype microfluidic device was also performed by particle tracking using fluorescent microscopy. Based on image processing, the capture data at different locations on the electrode surface is quantified as a function of the wall shear stress at these locations, which is calculated using CFD simulations. Finally, the Faradaic processes in the microchannel due to electrochemical reactions are studied to predict the amount of electrophoresis in the system. Scaling of the device to sample 5 L/hr can be achieved by stacking 835 identical microchannels. Power and wetted volume for the prototype and scaled devices are presented. The device can thus function either as a filtration unit or as a sample concentrator to enable the application of real-time detection sensor technologies. The ability to continuously sample water without chemical additives facilitates the use of this device in drinking water distribution systems. This work constitutes the first step in our development of a continuous, microbial capture and concentration system from large volumes of potable water

Increased System Fidelity for Navy Aviation Hypoxia Training

In 2009, the Naval Aviation Survival Training Program (NASTP) Trainer Management Team (TMT) identified a need for a next-generation normobaric mask-on hypoxia trainer with enhanced capabilities due to the lack of positive air pressure provided by existing capabilities. The lack of a positive pressure-on-demand airflow delivery for current mask-on hypoxia training has been cited as a potential training gap wherein 44% of students experience air hunger (Artino, Folga, & Vacchiano, 2009). As a result, it is unclear whether students are able to recognize more subtle symptoms of hypoxia or if they are masked by air hunger. To address this, researchers have investigated an innovative technology solution to deliver representative pressure-on-demand flow rates, thereby increasing training fidelity by replicating the air delivery method of aircraft systems. This research also provided an opportunity to seek additional novel advances. Reducing the logisitical footprint and increasing portability by removing the need for compressed gases was a goal to ease implementation within higher fidelity training simulators with limited space to increase immersive training opportunities. This paper will provide an overview of the training need and the technical approach to the training device development. Additionally, the authors will discuss the engineering and human subjects testing conducted to evaluate the system. The results will include how symptoms experienced using this novel device compare to historical data from other training systems, in addition to whether the system reduces or eliminates air hunger issues

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Augmenting globalization through strategic alliances : a roadmap for emerging Asian automobile companies

85 p.The primary objective of this dissertation is to, identify strategic alliances as a key strategy in the globalization initiative of emerging Asian automobile companies and develop a comprehensive road-map for forming these strategic alliances. The aim of this dissertation is to design a roadmap for Asian automobile companies to form strategic alliances through an enhanced understanding of global alliances in the light of the available theoretical literature and case studies. It has been attempted in this thesis to create a more comprehensive framework for specifically managing an alliance, as it would be characterized in a typical alliance of an Asian company with a western or a Japanese counterpart. By employing soft systems methodology, a as close to reality as possible problem scenario has been created and which has later been tried to be solved by using lessons from the theoretical frameworks and the case studies. The roadmap suggests 5 distinct stages for the strategic alliance which includes exploring the opportunities, partner selection; deciding the type of strategic alliance, design phase and alliance management.Master of Science (Computer Integrated Manufacturing