56 research outputs found
Otolith geochemistry does not reflect dispersal history of clownfish larvae
Author Posting. © The Author(s), 2010. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Coral Reefs 29 (2010): 883-891, doi:10.1007/s00338-010-0652-z.Natural geochemical signatures in calcified structures are commonly employed to retrospectively estimate dispersal pathways of larval fish and invertebrates. However, the accuracy of the approach is generally untested due to the absence of individuals with known dispersal histories. We used genetic parentage analysis (genotyping) to divide 110 new recruits of the orange clownfish, Amphiprion percula, from Kimbe Island, Papua New Guinea, into two groups: “self-recruiters” spawned by parents on Kimbe Island and “immigrants” that had dispersed from distant reefs (>10km away). Analysis of daily increments in sagittal otoliths found no significant difference in PLDs or otolith growth rates between self-recruiting and immigrant larvae. We also quantified otolith Sr/Ca and Ba/Ca ratios during the larval phase using laser ablation inductively coupled plasma mass spectrometry. Again, we found no significant differences in larval profiles of either element between self-recruits and immigrants. Our results highlight the need for caution when interpreting otolith dispersal histories based on natural geochemical tags in the absence of water chemistry data or known-origin larvae with which to test the discriminatory ability of natural tags.Research was supported by the Australian Research Council, the Coral Reef Initiatives for the Pacific (CRISP), the Global Environmental Facility CRTR Connectivity Working Group, the Total Foundation, a National Science Foundation grant (#0424688) to SRT, and a National Science Foundation Graduate Research Fellowship to MLB
The Dirac form factor predicts the Pauli form factor in the Endpoint Model
We compute the momentum-transfer dependence of the proton Pauli form factor
in the endpoint overlap model. We find the model correctly reproduces
the scaling of the ratio of with the Dirac Form factor observed
at the Jefferson Laboratory. The calculation uses the leading-power, leading
twist Dirac structure of the quark light-cone wave function, and the same
endpoint dependence previously determined from the Dirac form factor .
There are no parameters and no adjustable functions in the endpoint model's
prediction for . The model's predicted ratio
is quite insensitive to the endpoint wave function, which explains why the
observed ratio scales like down to rather low momentum transfers. The
endpoint model appears to be the only comprehensive model consistent with all
form factor information as well as reproducing fixed-angle proton-proton
scattering at large momentum transfer. Any one of the processes is capable of
predicting the others.Comment: 12 pages, 3 figure
Influenza and respiratory syncytial virus in infants study (IRIS) of hospitalized and non-ill infants aged <1 year in four countries: study design and methods
Uncovering the scaling laws of hard exclusive hadronic processes in a comprehensive endpoint model
Novel Approach Identifies SNPs in SLC2A10 and KCNK9 with Evidence for Parent-of-Origin Effect on Body Mass Index
Marja-Liisa Lokki työryhmien Generation Scotland Consortium, LifeLines Cohort Study ja GIANT Consortium jäsenPeer reviewe
Structural and Biochemical-Studies of Human Galanin - Nmr Evidence for Nascent Helical Structures in Aqueous-Solution
The 30-residue human neuropeptide, galanin, was shown to bind to rat insulinoma RINm5F cells and to inhibit glyceraldehyde-stimulated insulin secretion from these cells in a manner quantitatively similar to that of porcine, galanin. Neither human nor porcine galanin stimulated Ca2+ mobilization in cultured human small cell lung carcinoma cells. Sedimentation equilibrium analysis of human galanin showed that it was strictly monomeric in aqueous solution, indicating that the peptide interacts with its receptor(s) as a monomer. The monomeric nature of the peptide makes it especially suitable for structural studies using NMR. Nuclear Overhauser enhancement spectroscopy experiments performed on galanin dissolved in aqueous solution (150 mM KCl, pH 4) at both 33 and 3 degrees C indicate that certain regions of the peptide are capable of adopting detectable levels of short-range structure in rapid equilibrium with random coil. At 33 degrees C, the short-range structures include a nascent helix spanning residues 3-11 which incorporates a hydrophobic core from residues 6-11. Residues 14-18 and 22-30 display sequential NH-NH and (CH)-H-beta-NH connectivities, indicating that these regions of the peptide adopt nonrandom conformations by significantly populating the ct-region of conformational space. However, no medium-range dipolar connectivities indicative of nascent helix or turn conformations were observed. At 3 degrees C, almost all residues significantly populate the cr-region of conformational space, and the nascent helix between residues 3 and 11, with its hydrophobic core, is retained. As expected, circular dichroism (CD) was insensitive to the presence of short-range structure, and therefore the CD spectrum of human galanin in aqueous solution indicated a completely random coil peptide. However, changes in the CD spectrum resulting from the addition of 30% (v/v) of the helix-promoting organic solvent, trifluoroenthanol, indicated that similar to 6 residues of the peptide were transformed to stable helix
Analysis of the red cell membrane in a family with hereditary elliptocytosis — total or partial of protein 4.1
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