Open Access. Powered by Scholars. Published by Universities.®
- Institution
Articles 1 - 5 of 5
Full-Text Articles in Life Sciences
Circadian Modulation Of Astrocyte Morphology And Synaptic Transmission, Saad Ahmad
Circadian Modulation Of Astrocyte Morphology And Synaptic Transmission, Saad Ahmad
Biological Sciences
The circadian rhythm affects behavior and physiology in many animal species. Our previous work in mice showed that within the hippocampus, a subordinate circadian oscillator, astrocytes change their proximity to excitatory synapses. Here we obtain 3D reconstructions of biocytin-filled hippocampal astrocytes processed with protein retention expansion microscopy and imaged using two-photon laser scanning microscopy. Our findings identify the subtle changes in astrocyte morphologies that encode information about time-of-day in hippocampal astrocytes. These findings shed light on fundamental mechanisms that allow the function of hippocampal circuits to adapt to different times of the day. This will help us understand how structural …
Olfactory Behavioral Responses Of Mosquito Vectors To Select Attractants And Floral Scents As Related To Circadian Rhythms And Photoperiod Regimes, Bernadette A. Ferraro
Olfactory Behavioral Responses Of Mosquito Vectors To Select Attractants And Floral Scents As Related To Circadian Rhythms And Photoperiod Regimes, Bernadette A. Ferraro
Biomedical Sciences Theses & Dissertations
This dissertation discusses mosquito behavioral activities involving circadian rhythms defined as insect sensitivity to select of chemical volatiles that vary throughout the 24-hour day. Circannual rhythms occur over seasons varying in photoperiod, defined as the seasonal cycle of light and darkness. These cycles can be endogenously controlled by circadian clocks. The impetus for this research was initiated when reading about the neglected temporal dimension in the context of insect chemical ecology, including insect olfaction. It was proposed that sensitivity to odors does not change in general, but specific sensitivities could vary according to time of day. Chemical scents emitted by …
Expression, Purification, And Characterization Of Recombinant Human Npas2, Brenda Moreno
Expression, Purification, And Characterization Of Recombinant Human Npas2, Brenda Moreno
Open Access Theses & Dissertations
Many living organisms have biological clocks known as circadian rhythms that control various physiological and behavioral processes, tailored with the day and night. At the cellular level, the circadian clock drives daily rhythms with a transcriptional-translational feedback loop (TTFL) established by multiple transcription factors and genes under their regulation. Circadian Locomotor Output Cycles Kaput (CLOCK) and Brain and Muscle ARNT-like protein 1 (BMAL1) are two of those transcription factors, initiating the TTFL by forming a heterodimeric complex that bind to DNA promoters. Neuronal PAS domain protein 2 (NPAS2) is a functional analog to CLOCK. Less knowledge about NPAS2, in contrast …
Age And Seasonal Change In The Chronobiology Of A Spider With An Exceptionally Long-Period Circadian Clock, Shae Crain
Age And Seasonal Change In The Chronobiology Of A Spider With An Exceptionally Long-Period Circadian Clock, Shae Crain
Electronic Theses and Dissertations
This study examines locomotor activity in samples of Frontinella pyramitela collected over its active season (April-October) to investigate whether seasonality and/or age may help explain the exceptional variability typically found in spider clock systems. Despite its noteworthy variability (%CV= 7.7), we have found that Frontinella has a mean free-running period of 28.4±2.18 hours that does not significantly vary over time. There is no correlation between day length and free-running period, indicating that varying length of FRP is not a function of photoperiod length. In LD 12:12 h, the window of activity is significantly smaller in April, gradually widening as the …
Circadian Rhythm In Dugesia Tigrina And Its Correlation With Regeneration, Mary Michael Brandt
Circadian Rhythm In Dugesia Tigrina And Its Correlation With Regeneration, Mary Michael Brandt
Theses & Dissertations
Plant and animal rhythms have caught the attention of astute observers throughout history, but it was not until the eighteenth century that research in the area really began. Of the many rhythms we casually observe in the creatures around us, the most familiar is the daily rhythm of activity and rest. Ordinarily, the cues of daylight and darkness help to keep plants and animals synchronized with the environment. But neither honeybees, plants, nor man depend entirely upon such cues—all will show their "time sense" even when isolated from the outside world in a deep mine, cavern, or similar situation. In …