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111.
Bharath Ananthasubramaniam Roger M. Nisbet Daniel E. Morse Francis J. Doyle III 《Theoretical Ecology》2011,4(1):69-85
The circa-annual cycle of gametogenesis produces mature gametes at the spawning “season” for successful mass spawning of broadcast
corals. We develop a bioenergetic integrate-and-fire model that reveals how annual insolation rhythms can entrain the gametogenetic
cycles in tropical hermatypic corals to the appropriate spawning season, since photosynthate is their primary source of energy.
In the presence of short-term fluctuations in the energy input, a feedback regulatory mechanism is likely required to achieve
coherence of spawning times to within one lunar cycle, in order for subsequent signals such as lunar and diurnal light cycles
to unambiguously determine the “correct” night of spawning. The feedback mechanism can also provide robustness against population
heterogeneity that may arise due to genetic and environmental effects. We solve the integrate-and-fire bioenergetic model
numerically using the Fokker–Planck equation and use analytical tools such as rotation number to study entrainment. 相似文献
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Erdei E Sheng H Maestas E Mackey A White KA Li L Dong Y Taylor J Berwick M Morse DE 《PloS one》2011,6(8):e23950
Background
Hispanics are known to be an extremely diverse and genetically admixed ethnic group. The lack of methodologies to control for ethnicity and the unknown admixture in complex study populations of Hispanics has left a gap in understanding certain cancer disparity issues. Incidence rates for oral and pharyngeal cancer (OPC) in Puerto Rico are among the highest in the Western Hemisphere. We conducted an epidemiological study to examine risk and protective factors, in addition to possible genetic susceptibility components, for oral cancer and precancer in Puerto Rico.Methodology/Principal Findings
We recruited 310 Puerto Rico residents who had been diagnosed with either an incident oral squamous cell carcinoma, oral precancer, or benign oral condition. Participants completed an in-person interview and contributed buccal cells for DNA extraction. ABI Biosystem Taqman™ primer sets were used for genotyping 12 ancestry informative markers (AIMs). Ancestral group estimates were generated using maximum likelihood estimation software (LEADMIX), and additional principal component analysis was carried out to detect population substructures. We used unconditional logistic regression to assess the contribution of ancestry to the risk of being diagnosed with either an oral cancer or precancer while controlling for other potential confounders. The maximum likelihood estimates showed that study participants had a group average ancestry contribution of 69.9% European, 24.5% African, and 5.7% detectable Native American. The African and Indigenous American group estimates were significantly higher than anticipated. Neither self-identified ethnicity nor ancestry markers showed any significant associations with oral cancer/precancer risk in our study.Conclusions/Significance
The application of ancestry informative markers (AIMs), specifically designed for Hispanics, suggests no hidden population substructure is present based on our sampling and provides a viable approach for the evaluation and control of ancestry in future studies involving Hispanic populations. 相似文献114.
As a reported agonist,11C-CUMI-101 is believed to selectively bind the G-protein-coupled state of the serotonin-1A (5-HT1A) receptor, thereby providing a measure of the active subset of all 5-HT1A receptors in brain. Although 11C-CUMI-101 has been successfully used to quantify 5-HT1A receptors in human and monkey brain, its radiation exposure has not previously been reported. The purpose of this study was to calculate the radiation exposure to organs of the body based on serial whole-body imaging with positron emission tomography (PET) in human subjects.
Methods
Nine healthy volunteers were injected with 428±84 MBq (mean ± SD) 11C-CUMI-101 and then imaged with a PET-only device for two hours from head to mid-thigh. Eleven source organs (brain, heart, liver, pancreas, stomach, spleen, lungs, kidneys, lumbar spine L1-5, thyroid, and urinary bladder) were identified on whole body images and used to calculate radiation doses using the software program OLINDA/EXM 1.1. To confirm that we had correctly identified the pancreas, a tenth subject was imaged on a PET/CT device.Results
Brain had high uptake (∼11% of injected activity (IA)) at 10 min. Although liver had the highest uptake (∼35% IA at 120 min), excretion of this activity was not visible in gall bladder or intestine during the scanning session. Organs which received the highest doses (microSv/MBq) were pancreas (32.0), liver (18.4), and spleen (14.5). The effective dose of 11C-CUMI-101 was 5.3±0.5 microSv/MBq.Conclusion
The peak brain uptake (∼11% IA) of 11C-CUMI-101 is the highest among more than twenty 11C-labeled ligands reported in the literature and provides good counting statistics from relatively low injected activities. Similar to that of other 11C-labeled ligands for brain imaging, the effective dose of 11C-CUMI-101 is 5.3±0.5 microSv/MBq, a value that can now be used to estimate the radiation risks in future research studies. 相似文献115.
Data include charts and tables of absorbance and fluorescence of 4 coupling agents for immunity reactions, 34 typical fluorescent dyes and reagents, and 12 dyes or reagents having no fluorescence in solution but which may be fluorescent in the dry state. Since this report consists largely of reference data, the original must be consulted for details. Reprint source: The Perkin-Elmer Corporation, Norwalk, Connecticut, U. S. A. 相似文献
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This paper supplements a previous report: Stain Techn. 38, 37-48, 1963. Spectra and tables of data are given for 11 fluorescent dyes in solution, 6 to clarify nomenclature, 3 for which fluorescence had not been observed, and 2 as controls. Improved instrumentation was used. Since this report consists largely of reference data, the original must be consulted for details. Reprint source: The Perkin-Elmer Corporation, Norwalk, Connecticut 06852, U. S. A. 相似文献
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