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171.
Breeding latitude leads to different temporal but not spatial organization of the annual cycle in a long‐distance migrant
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Martins Briedis Steffen Hahn Lars Gustafsson Ian Henshaw Johan Träff Miroslav Král Peter Adamík 《Journal of avian biology》2016,47(6):743-748
The temporal and spatial organization of the annual cycle according to local conditions is of crucial importance for individuals’ fitness. Moreover, which sites and when particular sites are used can have profound consequences especially for migratory animals, because the two factors shape interactions within and between populations, as well as between animal and the environment. Here, we compare spatial and temporal patterns of two latitudinally separated breeding populations of a trans‐Equatorial passerine migrant, the collared flycatcher Ficedula albicollis, throughout the annual cycle. We found that migration routes and non‐breeding residency areas of the two populations largely overlapped. Due to climatic constraints, however, the onset of breeding in the northern population was approximately two weeks later than that of the southern population. We demonstrate that this temporal offset between the populations carries‐over from breeding to the entire annual cycle. The northern population was consistently later in timing of all subsequent annual events – autumn migration, non‐breeding residence period, spring migration and the following breeding. Such year‐round spatiotemporal patterns suggest that annual schedules are endogenously controlled with breeding latitude as the decisive element pre‐determining the timing of annual events in our study populations. 相似文献
172.
Johan Decelle Hryhoriy Stryhanyuk Benoit Gallet Giulia Veronesi Matthias Schmidt Sergio Balzano Sophie Marro Clarisse Uwizeye Pierre-Henri Jouneau Josselin Lupette Juliette Jouhet Eric Maréchal Yannick Schwab Nicole L. Schieber Rémi Tucoulou Hans Richnow Giovanni Finazzi Niculina Musat 《Current biology : CB》2019,29(6):968-978.e4
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175.
Benedetta Artegiani Lisa van Voorthuijsen Rik G.H. Lindeboom Daniëlle Seinstra Inha Heo Pablo Tapia Carmen López-Iglesias Daniel Postrach Talya Dayton Rurika Oka Huili Hu Ruben van Boxtel Johan H. van Es Johan Offerhaus Peter J. Peters Jacco van Rheenen Michiel Vermeulen Hans Clevers 《Cell Stem Cell》2019,24(6):927-943.e6
176.
Local polarity and hydrogen bonding inside the Sec14p phospholipid-binding cavity: high-field multi-frequency electron paramagnetic resonance studies
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Smirnova TI Chadwick TG Voinov MA Poluektov O van Tol J Ozarowski A Schaaf G Ryan MM Bankaitis VA 《Biophysical journal》2007,92(10):3686-3695
Sec14p promotes the energy-independent transfer of either phosphatidylinositol (PtdIns) or phosphatidylcholine (PtdCho) between lipid bilayers in vitro and represents the major PtdIns/PtdCho transfer protein in the budding yeast Saccharomyces cerevisiae. Herein, we employ multi-frequency high-field electron paramagnetic resonance (EPR) to analyze the electrostatic and hydrogen-bonding microenvironments for series of doxyl-labeled PtdCho molecules bound by Sec14p in a soluble protein-PtdCho complex. A structurally similar compound, 5-doxyl stearic acid dissolved in a series of solvents, was used for experimental calibration. The experiments yielded two-component rigid limit 130- and 220-GHz EPR spectra with excellent resolution in the gx region. Those components were assigned to hydrogen-bonded and nonhydrogen-bonded nitroxide species. Partially resolved 130-GHz EPR spectra from n-doxyl-PtdCho bound to Sec14p were analyzed using this two-component model and allowed quantification of two parameters. First, the fraction of hydrogen-bonded nitroxide species for each n-doxyl-PtdCho was calculated. Second, the proticity profile along the phospholipid-binding cavity of Sec14p was characterized. The data suggest the polarity gradient inside the Sec14p cavity is a significant contributor to the driving molecular forces for extracting a phospholipid from the bilayer. Finally, the enhanced g-factor resolution of EPR at 130 and 220 GHz provides researchers with a spectroscopic tool to deconvolute two major contributions to the x-component of the nitroxide g-matrix: hydrogen-bond formation and local electrostatic effects. 相似文献
177.
Sebolai OM Pohl CH Botes PJ Strauss CJ van Wyk PW Botha A Kock JL 《Canadian journal of microbiology》2007,53(6):809-812
Using immunofluorescence confocal laser scanning microscopy, immunogold transmission electron microscopy and gas chromatography--mass spectrometry, we demonstrated the presence of 3-hydroxy fatty acids in Cryptococcus neoformans. Our results suggest that these oxylipins accumulate in capsules where they are released as hydrophobic droplets through tubular protuberances into the surrounding medium. 相似文献
178.
Ann Margaret Grøndahl Ellen Margrete Skancke Cecilie Marie Mejdell Johan Høgset Jansen 《Acta veterinaria Scandinavica》2007,49(1):16
Over a period of two years, growth rate and health were measured for dairy calves allowed to suckle their mothers up to 6–8
weeks of age. Thirty-one calves were weighted weekly, and the mean daily growth rate was 1.2 ± 0.03 kg from birth up to 13
weeks of age. Illness in calves and young stock was not observed. In the cows, the mean incidences of ketosis, displaced abomasum,
puerperal paresis, mastitis, teat injury and retained placenta were 0, 0, 8, 22, 1 and 1%, respectively, during a 6-year period.
The mean daily gain of 56 growing bulls was 1.4 kg when slaughtered at 15 months of age, which is higher than the mean daily
gain of 0.95 kg in the population. Probiotics, hormones and vaccines were not used, and antibiotics were only used for treating
illness. The present study indicates many advantages and few problems when dairy calves are penned together with the cows
and allowed natural feeding up to 6–8 weeks of age. This production system was easy to manage, preferred by the farmer, and
may satisfy the public concern regarding the practice of immediate separation of cow and calf in commercial milk production. 相似文献
179.
180.
van Platerink CJ Janssen HG Haverkamp J 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,846(1-2):147-154
A fast at-line method was developed for the identification of ACE inhibiting (ACEI) peptides in protein hydrolysates. The method consists of activity measurements of fractions collected from a two-dimensional HPLC fractionation of the peptide mixture followed by MS identification of the peptides in the inhibiting fractions. The inhibition assay is based on the inhibiting effect of ACEI peptides on the hydrolytic scission of the substrate Hippuric acid-His-Leu (HHL) during the ACE-catalysed hydrolysis reaction. A fast LC method was developed for the quantification of Hippuric acid (H) and Hippuric acid-Histidine-Leucine (HHL), allowing a large number of fractions to be analysed within a reasonable time period. The method is sensitive and uses only standard laboratory equipment. The limit of detection is 0.34 microM for the known ACEI peptide IPP. This is sufficiently sensitive for the identification of only moderately active peptides and/or ACEI peptides present at low concentrations. The relative standard deviation of the inhibition assay was 12% measured over a time period of 2 months. The IC50 value of IPP measured with the assay was 5.6 microM, which is comparable to the values of 5 microM and 5.15 microM reported in literature for the standard Matsui method. The assay was successfully applied in the identification of ACEI peptides in enzymatically hydrolysed caseinate samples. Two new, not earlier published ACEI peptides were identified; MAP (beta-casein f102-104) and ITP (alpha-s2-casein f119-121) with IC50 values of 3.8 microM and 50 microM, respectively. 相似文献