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Abstract We introduce a novel optofluidic solar concentration system based on electrowetting tracking. With two immiscible fluids in a transparent cell, we can actively control the orientation of fluid–fluid interface via electrowetting. The naturally-formed meniscus between the two liquids can function as a dynamic optical prism for solar tracking and sunlight steering. An integrated optofluidic solar concentrator can be constructed from the liquid prism tracker in combination with a fixed and static optical condenser (Fresnel lens). Therefore, the liquid prisms can adaptively focus sunlight on a concentrating photovoltaic (CPV) cell sitting on the focus of the Fresnel lens as the sun moves. Because of the unique design, electrowetting tracking allows the concentrator to adaptively track both the daily and seasonal changes of the sun’s orbit (dual-axis tracking) without bulky, expensive and inefficient mechanical moving parts. This approach can potentially reduce capital costs for CPV and increases operational efficiency by eliminating the power consumption of mechanical tracking. Importantly, the elimination of bulky tracking hardware and quiet operation will allow extensive residential deployment of concentrated solar power. In comparison with traditional silicon-based photovoltaic (PV) solar cells, the electrowetting-based self-tracking technology will generate ∼70% more green energy with a 50% cost reduction.

Abstract We introduce a novel optofluidic solar concentration system based on electrowetting tracking. With two immiscible fluids in a transparent cell, we can actively control the orientation of fluid–fluid interface via electrowetting. The naturally-formed meniscus between the two liquids can function as a dynamic optical prism for solar tracking and sunlight steering. An integrated optofluidic solar concentrator can be constructed from the liquid prism tracker in combination with a fixed and static optical condenser (Fresnel lens). Therefore, the liquid prisms can adaptively focus sunlight on a concentrating photovoltaic (CPV) cell sitting on the focus of the Fresnel lens as the sun moves. Because of the unique design, electrowetting tracking allows the concentrator to adaptively track both the daily and seasonal changes of the sun’s orbit (dual-axis tracking) without bulky, expensive and inefficient mechanical moving parts. This approach can potentially reduce capital costs for CPV and increases operational efficiency by eliminating the power consumption of mechanical tracking. Importantly, the elimination of bulky tracking hardware and quiet operation will allow extensive residential deployment of concentrated solar power. In comparison with traditional silicon-based photovoltaic (PV) solar cells, the electrowetting-based self-tracking technology will generate ∼70% more green energy with a 50% cost reduction.

Embryonic murine neuronal networks cultured on substrate-integrated microelectrode arrays were used to quantify acute electrophysiological effects of ethanol by using extracellular, multichannel recording of action potentials. Spontaneously active frontal cortex cultures showed repeatable, concentration-dependent sensitivities to ethanol, with initial inhibition at 20 mM and a spike rate 50% effective concentration (EC50) of 48.8+/-5.4 mM. Ethanol concentrations of greater than 100 mM led to cessation of activity. The ethanol inhibitions up to the maximum tested 160 mM were reversible. Although ethanol did not change the shape of action potentials, unit-specific spike pattern effects were found. At 40 mM, ethanol decreased neuronal firing in 71%, increased firing in 20%, and generated no effect in 9% of all units observed (14 cultures, 200 discriminated units). The effects of combined application of ethanol and fluoxetine were additive. Excellent agreement with findings obtained from experimental studies with animals validates the use of these in vitro systems for alcohol research.

Embryonic murine neuronal networks cultured on substrate-integrated microelectrode arrays were used to quantify acute electrophysiological effects of ethanol by using extracellular, multichannel recording of action potentials. Spontaneously active frontal cortex cultures showed repeatable, concentration-dependent sensitivities to ethanol, with initial inhibition at 20 mM and a spike rate 50% effective concentration (EC50) of 48.8+/-5.4 mM. Ethanol concentrations of greater than 100 mM led to cessation of activity. The ethanol inhibitions up to the maximum tested 160 mM were reversible. Although ethanol did not change the shape of action potentials, unit-specific spike pattern effects were found. At 40 mM, ethanol decreased neuronal firing in 71%, increased firing in 20%, and generated no effect in 9% of all units observed (14 cultures, 200 discriminated units). The effects of combined application of ethanol and fluoxetine were additive. Excellent agreement with findings obtained from experimental studies with animals validates the use of these in vitro systems for alcohol research.

The driving motive of this work is to enhance the tolerability of a flat Fresnel-lens concentrator to tracking errors, without the use of secondary optics or sophisticated, and normally costly, meticulous tracking equipment. This is achieved by optimizing the prismatic geometry of the Fresnel lens through a statistical approach that incorporates laws of light refraction and trigonometry. The proposed design produces high focal heat flux that is more suitable for thermal applications. A comparative simulation analysis was conducted for two case studies from literature, each with a different design method for the Fresnel lens. On basis of equivalent geometric concentration ratio and f-number, the flat-spot lenses, designed by this study, returned higher values of the concentration acceptance product ( $$CAP$$ ). In case #1 of a 212× cylindrical lens with an f-number of unity, an equivalent flat lens by this work almost doubled the $$CAP$$ from 0.165 to 0.34. For the design case #2 of a 559× aspheric Fresnel lens made by simple geometrical optics, a 60.7% enhanced $$CAP$$ was achieved by this work’s lens, from 0.206 to 0.331, at an f-number of 0.83.

The driving motive of this work is to enhance the tolerability of a flat Fresnel-lens concentrator to tracking errors, without the use of secondary optics or sophisticated, and normally costly, meticulous tracking equipment. This is achieved by optimizing the prismatic geometry of the Fresnel lens through a statistical approach that incorporates laws of light refraction and trigonometry. The proposed design produces high focal heat flux that is more suitable for thermal applications. A comparative simulation analysis was conducted for two case studies from literature, each with a different design method for the Fresnel lens. On basis of equivalent geometric concentration ratio and f-number, the flat-spot lenses, designed by this study, returned higher values of the concentration acceptance product ( $$CAP$$ ). In case #1 of a 212× cylindrical lens with an f-number of unity, an equivalent flat lens by this work almost doubled the $$CAP$$ from 0.165 to 0.34. For the design case #2 of a 559× aspheric Fresnel lens made by simple geometrical optics, a 60.7% enhanced $$CAP$$ was achieved by this work’s lens, from 0.206 to 0.331, at an f-number of 0.83.

To examine the effect of post-resistance exercise alcohol ingestion on lipopolysaccharide (LPS)-stimulated production of IFNγ, TNF-α, IL-1β, IL-6, IL-8, and IL-10.Recreationally resistance-trained men (n = 10, 25 ± 3 year, 177 ± 7 cm, 83.8 ± 15.7 kg, 14.8 ± 8.5% body fat) and women (n = 8, 23 ± 2 year, 161 ± 3 cm, 59.5 ± 6.0 kg, 26.5 ± 3.0% body fat) completed two identical heavy back squat sessions (6 × 10 at 80% 1 repetition maximum) followed by ingestion of either an alcohol (ALC; 1.09 g ethanol · kg fat-free mass(-1)) or water (PLA) drink. Blood samples were collected before exercise (PRE), and at 3 h (3 h), and 5 h (5 h) after exercise, stimulated with LPS, and analyzed for IFNγ, TNF-α, IL-1β, IL-6, IL-8, and IL-10 concentrations.There were no drink conditions by time effects for IFNγ, TNF-α, IL-1β, or IL-10. Regardless of condition, resistance exercise induce an increase in IFNγ, TNF-α, and IL-1β at 5 h compared to PRE but a decrease in IL-10 at 3 and 5 h compared to PRE. For ALC, IL-8 was reduced at 5 h compared to PLA. From PRE to 3 h, IL-6 was reduced for ALC but increased for PLA; resistance exercise induced an increase in IL-6 for both conditions at 5 h.Heavy resistance exercise increased production of IFNγ, TNF-α, IL-1β, and Il-6 and decreased production of IL-10. Alcohol ingestion after resistance exercise affected aspects of inflammatory capacity (IL-6 and IL-8 production). It appears that some of the effects previously observed for alcohol ingestion alone on the LPS-stimulated cytokine production were overwhelmed by the response to resistance exercise.

To examine the effect of post-resistance exercise alcohol ingestion on lipopolysaccharide (LPS)-stimulated production of IFNγ, TNF-α, IL-1β, IL-6, IL-8, and IL-10.Recreationally resistance-trained men (n = 10, 25 ± 3 year, 177 ± 7 cm, 83.8 ± 15.7 kg, 14.8 ± 8.5% body fat) and women (n = 8, 23 ± 2 year, 161 ± 3 cm, 59.5 ± 6.0 kg, 26.5 ± 3.0% body fat) completed two identical heavy back squat sessions (6 × 10 at 80% 1 repetition maximum) followed by ingestion of either an alcohol (ALC; 1.09 g ethanol · kg fat-free mass(-1)) or water (PLA) drink. Blood samples were collected before exercise (PRE), and at 3 h (3 h), and 5 h (5 h) after exercise, stimulated with LPS, and analyzed for IFNγ, TNF-α, IL-1β, IL-6, IL-8, and IL-10 concentrations.There were no drink conditions by time effects for IFNγ, TNF-α, IL-1β, or IL-10. Regardless of condition, resistance exercise induce an increase in IFNγ, TNF-α, and IL-1β at 5 h compared to PRE but a decrease in IL-10 at 3 and 5 h compared to PRE. For ALC, IL-8 was reduced at 5 h compared to PLA. From PRE to 3 h, IL-6 was reduced for ALC but increased for PLA; resistance exercise induced an increase in IL-6 for both conditions at 5 h.Heavy resistance exercise increased production of IFNγ, TNF-α, IL-1β, and Il-6 and decreased production of IL-10. Alcohol ingestion after resistance exercise affected aspects of inflammatory capacity (IL-6 and IL-8 production). It appears that some of the effects previously observed for alcohol ingestion alone on the LPS-stimulated cytokine production were overwhelmed by the response to resistance exercise.

Abstract The dynamic stability of Boiling Water Reactors (BWR's) is influenced by the reactor control system and its interaction with external load demand, channel thermal hydraulic properties, and coupled neutronic-thermal-hydraulic dynamics. The latter aspect of BWR stability which is affected by void reactivity feedback, coolant flow rate and fuel-to-coolant heat transfer characteristics is studied in this paper using the normal fluctuation data. The feasibility of overall core stability trend monitoring using neutron noise and the relationship between stability and two-phase flow velocity in a fuel channel are studied. Time series modeling of the average power range monitor (APRM) detector signal, and bivariate analysis of adjacent local power range monitor (LPRM) detector signals are used to determine the neutron impulse response, spectral characteristics and two-phase flow velocity using data from an operating BWR. The results of analysis show that the APRM noise signal can be used to monitor changes in the closed-loop output stability of BWRs (but not the absolute stability as determined by the reactivity-to-neutron power transfer function), and that a positive correlation exists between stability and two-phase flow velocity in a fuel channel. Furthermore, the temporal behavior of the neutron signal for short and long data records indicates that there is no smoothing of the spectral resonance frequency, nor subsequent distortion of the computed decay ratio when long data records were used. The primary perturbation source affecting the void reactivity is being investigated using the relationship between APRM signal and the process variables.