A modified rapid flow technique was used in order to measure the rate of oxygen transfer out of red blood cells of different ages. The oxygen transfer rate is expressed as a mass transfer coefficient determined in blo...
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A modified rapid flow technique was used in order to measure the rate of oxygen transfer out of red blood cells of different ages. The oxygen transfer rate is expressed as a mass transfer coefficient determined in blood samples that were stored in the local blood bank for different periods of time. The results show that the resistance to oxygen transfer increases with age. This suggests that the decrease in the quality of stored blood is due, partially at least, to changes in the red blood cell membrane. The method can also provide a functional way of testing the quality of stored blood.
The use of radionuclides for therapeutic and diagnostic purposes is the primary function of nuclear medicine. Among these radionuclides, the iodine family stands out as isotopes that can serve various purposes, includ...
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The mechanism of microdroplet coalescence is a fundamental issue for droplet-based microfluidics. We developed an asymmetric expansion (a rectangular groove) along one side of a microchannel to achieve multiple-microd...
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The mechanism of microdroplet coalescence is a fundamental issue for droplet-based microfluidics. We developed an asymmetric expansion (a rectangular groove) along one side of a microchannel to achieve multiple-microdroplet trapping, collision, and coalescence. Compared with reported symmetric expansions, this asymmetric groove could easily trap microdroplets and control two or three microdroplet coalescences precisely without a requirement for temporal and spatial synchronization. To reveal the mechanisms of multiple-droplet coalescences in a groove, we observed five different coalescence patterns under different flow conditions. Moreover, we characterized the flow behavior quantitatively by simulating the velocity vector fields in both the microdroplets and continuous phase, finding good agreement with experiments. Finally, a map of coalescence forms with different capillary numbers () and flow ratios () was obtained. The results could provide a useful guidance for the design and application of droplet-based microfluidic devices.
This paper extends the systematic approach described in Winters and Stark (62) for developing muscle models. The underlying motivation is our finding that for larger scale shoulder and head-neck postural systems to be...
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This paper extends the systematic approach described in Winters and Stark (62) for developing muscle models. The underlying motivation is our finding that for larger scale shoulder and head-neck postural systems to be mechanically stable, open-loop muscle properties are often not sufficient. There are three primary contributions. First, the previous muscle mechanical model structure and parameter estimation process of (62) is updated to reflect recent experimental findings. Second, an intrafusal (IF) muscle model is developed that includes a gamma(static) motoneuron (MN) drive, a Hill muscle model, and a muscle spindle sensor across the IF series element;this provides a more appropriate muscle spindle output signal, especially for studies of posture. Third, the conceptual cut between the neurocontrol input and the actuator is raised from just below the MN summing junction to a higher location, allowing a muscle-reflex actuator'' to be defined that satisfies the formal theoretical requirement for possessing passive spring-like behavior when the neurocontrol input is constant, alpha-gamma MN coactivation is assumed, and three types of intrinsic autogenic reflex responses (spindle, Golgi tendon organ, Rhenshaw cell) are developed. Default feedback gains are set based on the criteria that inherent feedback should not sculpt the feedforward excitation drive by more than +/- 10% of maximum. This new actuator model only mildly affects voluntary goal-directed dynamic performance, but enhances spring-like performance around the postural equilibrium state, in line with available animal and human studies and with several theories on postural regulation.
The bubbly flow regime inside orifices has significant effects on several applications, and studying its trend along an orifice could be helpful in identifying the flow mechanism in various situations. The flow regime...
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The bubbly flow regime inside orifices has significant effects on several applications, and studying its trend along an orifice could be helpful in identifying the flow mechanism in various situations. The flow regime inside an orifice depends on the situation which has been specified for the orifice. Orifice geometry has a considerable effect on bubbly flow in injectors. Meanwhile, spray characteristics are influenced by the fuel flow inside an orifice, which has strong effects on the mixture of fuel-air. In this study, spray characteristics are studied for different values of the orifice angle. The cavitation phenomenon which occurs inside an orifice varies in intensity and patterns at different angles of the orifice and consequently has diverse effects on spray characteristics. The governing equations are solved by the SIMPLE algorithm. The spray flow is modeled by the discrete droplet method（DDM）, the droplet breakup is modeled by the WAVE model, and the primary breakup is modeled by the DIESEL BREAK UP model. In order to generate cavitation phenomenon inside orifices and investigate its effect on spray characteristics, the angle of orifice with respect to the injector body is varied and the problem is studied for different angles of orifice.
Advancements in high-frequency communication devices have emphasized miniaturization and low energy consumption. This work focuses on developing microwave dielectric materials characterized by an ultra-low dielectric ...
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Background: Understanding the role of musculoskeletal afferents in health and disease relies on the ability to selectively label afferents. Traditional approaches involve using adeno-associated viral (AAV) tools to tr...
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Schwann cells (SCs) hold key roles in axonal function and maintenance in the peripheral nervous system (PNS) and are a critical component to the regeneration process following trauma. Following PNS trauma, SCs respond...
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