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Core clock genes modulate the sleep-feeding axis
Title
Core clock genes modulate the sleep-feeding axis.
Creator
Murphy, Keith Richard, Bruce, Kimberly, Dawson-Scully, Ken, Graduate College, Ja, William W.
Abstract/Description
Sleep and feeding are processes essential to nearly all complex organisms, impacting the behavioral output of an animal through homeostatic drive. In Drosophila melanogaster it has been shown that starvation leads to sleep suppression through the signaling of core clock proteins that regulate the animal circadian rhythm. Furthermore overexpression of short neuropeptide, a sleep-promoting inhibitory modulator, increases sleep in animals and alters feeding behavior. While these findings provide...
Show moreSleep and feeding are processes essential to nearly all complex organisms, impacting the behavioral output of an animal through homeostatic drive. In Drosophila melanogaster it has been shown that starvation leads to sleep suppression through the signaling of core clock proteins that regulate the animal circadian rhythm. Furthermore overexpression of short neuropeptide, a sleep-promoting inhibitory modulator, increases sleep in animals and alters feeding behavior. While these findings provide a framework of the interaction between the pressures to feed and sleep, they are bi-modal shifts, limiting the understanding of this relationship between to its extreme states. Using the Activity Recording CAFÉ ARC, a tool for measuring the sleep and feeding of individual flies, we tuned either behavior and observed corresponding effects. By shifting food concentrations we are able to control hunger state of an animal while recording its sleep and activity patterns. By coupling this system with a gentle air puff we were also able to control sleep while measuring feeding. We found that the hunger state of an animal had a direct effect on sleep and sleep consolidation. Conversely, we show that increasing sleep pressure led to increased feeding and reduced satiety as calculated through the animal’s prandial behavior. In addition, we show that the direct relationship of the sleep/feeding is disrupted by core clock gene mutations but not by secondary clock genes such as period. By use of the ARC and bi-directional perturbation, we provide a higher resolution understanding of the sleep-feeding axis.
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Date Issued
2014
PURL
http://purl.flvc.org/fau/fd/FA00005843
Format
Document (PDF)
An American way to talk: forums as civic education in the 1930s
Title
An American way to talk: forums as civic education in the 1930s.
Creator
Keith, William, Jack Miller Forum, Department of Political Science, Dorothy F. Schmidt College of Arts and Letters
Date Issued
2009-01-30
PURL
http://purl.flvc.org/fau/fd/FADT186663p
Subject Headings
Civics -- Study and teaching -- United States, Adult education -- United States, Political socialization -- United States
Format
Set of related objects
Calcareous deposits in simulated fatigue cracks of cathodically protected steel in seawater
Title
Calcareous deposits in simulated fatigue cracks of cathodically protected steel in seawater.
Creator
Davidson, Keith Dewayne., Florida Atlantic University, Haratt, William H.
Abstract/Description
An experiment was designed to provide a simulated steel fatigue crack under cathodic protection in seawater for study. Calcareous deposits were found to form in the simulated crack at -0.800, -0.900, -1.000 and -1.100 volts (SCE) with cycle frequencies of both 0.5 and 1.0 Hertz. By X-ray and SEM analysis, calcium carbonate deposits were shown to grow in quantities sufficient to block and become compressed by this simulated crack. Increased fluid velocities from crack pumping were shown to...
Show moreAn experiment was designed to provide a simulated steel fatigue crack under cathodic protection in seawater for study. Calcareous deposits were found to form in the simulated crack at -0.800, -0.900, -1.000 and -1.100 volts (SCE) with cycle frequencies of both 0.5 and 1.0 Hertz. By X-ray and SEM analysis, calcium carbonate deposits were shown to grow in quantities sufficient to block and become compressed by this simulated crack. Increased fluid velocities from crack pumping were shown to negatively affect crystal nucleation and growth. Due to kinetic barriers to crystal growth, aragonite and brucite were determined to be the most likely deposit type; excluding calcite, dolomite and magnesite. The deposits formed at -1.000V were shown by current requirements and SEM to provide the best protection as a coating.
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Date Issued
1988
PURL
http://purl.flvc.org/fcla/dt/14442
Subject Headings
Steel--Fatigue, Cathodic protection, Sea-water corrosion
Format
Document (PDF)
Potential attenuation and anode current output determination alternatives for galvanic anode cathodic protection upon offshore pipelines
Title
Potential attenuation and anode current output determination alternatives for galvanic anode cathodic protection upon offshore pipelines.
Creator
Bethune, Keith P., Florida Atlantic University, Hartt, William H.
Abstract/Description
A recently developed equation governing cathodic polarization attenuation along a pipeline protected by galvanic anodes is first solved. The solution is based upon a numerical finite difference method (FDM). The resulting subroutine computes the polarization along the cathode and the corresponding anode current output based upon the physical design variables and electrochemical properties of the cathode. Validation of this method is accomplished through comparisons with a proven existing...
Show moreA recently developed equation governing cathodic polarization attenuation along a pipeline protected by galvanic anodes is first solved. The solution is based upon a numerical finite difference method (FDM). The resulting subroutine computes the polarization along the cathode and the corresponding anode current output based upon the physical design variables and electrochemical properties of the cathode. Validation of this method is accomplished through comparisons with a proven existing method for attenuation prediction, namely the Boundary Element Method (BEM). As both the FDM and BEM solutions are mathematically complex and time consuming, it is then demonstrated that a modified form of Ohm's Law that quantitatively interrelates (1) design life, (2) anode size, weight, and properties, (3) pipe size, current demand, and coating quality, (4) sea water resistivity, (5) magnitude of polarization, and (6) anode spacing is sufficient for design purposes where metallic resistance of the pipeline itself is negligible. This new method can be easily adapted in a spreadsheet type analysis as no numerical subroutine is necessary. One size pipeline of varying lengths is analyzed using these methods for comparisons and validation and the effect of metallic resistance on attenuation profiles is examined. It is concluded that for small diameter pipelines with anode spacing up to 800 m metallic resistance is negligible, and thus all three methods can be used with reasonable confidence for spacings below 800 m. An analysis to illustrate the effect of a stratified electrolyte in the vicinity of the pipeline has been initiated and preliminary results are also presented.
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Date Issued
2000
PURL
http://purl.flvc.org/fcla/dt/12672
Subject Headings
Underwater pipelines, Pipelines--Cathodic protection
Format
Document (PDF)
Genetic and Neuronal Integration of Sleep and Feeding
Title
Genetic and Neuronal Integration of Sleep and Feeding.
Creator
Murphy, Keith Richard, Ja, William W., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
Abstract/Description
Accumulating evidence points to a fundamental connection between sleep and feeding behavior. However, the temporal, genetic, and neuronal architecture that defines these relationships is poorly understood. Drosophila are amenable to high-throughput studies and offer numerous genetic tools which have advanced our understanding of the mechanistic relationships between these behaviors. However, certain features of the sleep-feeding axis have remained elusive, largely due to the separate...
Show moreAccumulating evidence points to a fundamental connection between sleep and feeding behavior. However, the temporal, genetic, and neuronal architecture that defines these relationships is poorly understood. Drosophila are amenable to high-throughput studies and offer numerous genetic tools which have advanced our understanding of the mechanistic relationships between these behaviors. However, certain features of the sleep-feeding axis have remained elusive, largely due to the separate measurement of sleep and feeding. Here, I develop a system which simultaneously measures sleep and feeding in individual animals by employing high resolution machine vision tracking and micro-controller interface functionality. Using this system, I show that food consumption drives a transient rise in sleep, which depends on food quality, quantity, and timing of a meal. The leucokinin system mediates these effects, particularly in response to protein ingestion. We further use the system to examine sleep homeostasis and demonstrate sleep dependence on energy expenditure and fat-brain communication. Collectively, these findings provide novel insight into the fundamental connections between sleep and feeding behavior.
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Date Issued
2018
PURL
http://purl.flvc.org/fau/fd/FA00005972
Subject Headings
Sleep, Feeding, Drosophila
Format
Document (PDF)
Postprandial sleep mechanics in Drosophila
Title
Postprandial sleep mechanics in Drosophila.
Creator
Murphy, Keith R, Deshpande, Sonali A, Yurgel, Maria E, Quinn, James P, Weissbach, Jennifer L, Keene, Alex C, Dawson-Scully, Ken, Huber, Robert, Tomchik, Seth M, Ja, William W
Date Issued
2016-11-22
PURL
http://purl.flvc.org/fau/flvc_fau_islandoraimporter_10.7554_eLife.19334_1644866459
Format
Document (PDF)