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Antoine Wystrach Sebastian Schwarz Patrick Schultheiss Guy Beugnon Ken Cheng 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2011,197(2):167-179
The Australian desert ant Melophorus bagoti often follows stereotypical routes through a cluttered landscape containing both distant panoramic views and obstacles (plants)
to navigate around. We created an artificial obstacle course for the ants between a feeder and their nest. Landmarks comprised
natural objects in the landscape such as logs, branches, and tussocks. Many ants travelled stereotypical routes home through
the obstacle course in training, threading repeatedly the same gaps in the landmarks. Manipulations altering the relations
between the landmarks and the surrounding panorama, however, affected the routes in two major ways. Both interchanging the
positions of landmarks (transpositions) and displacing the entire landmark set along with the starting position of the ants
(translations) (1) reduced the stereotypicality of the route, and (2) increased turns and meanders during travel. The ants
might have used the entire panorama in view-based travel, or the distal panorama might prime the identification and use of
landmarks en route. Despite the large data set, both options (not mutually exclusive) remain viable. 相似文献
3.
zge Karayel Francesca Tonelli Sebastian Virreira Winter Phillip E. Geyer Ying Fan Esther M. Sammler Dario R. Alessi Martin Steger Matthias Mann 《Molecular & cellular proteomics : MCP》2020,19(9):1546-1560
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- •MS-based clinical assay that accurately determines phospho Rab10 occupancy.
- •Stable isotope labeled phosphopeptide injected as a standard with endogenous tryptic phospho Rab peptide for accurate ratio determination.
- •Determination of pRab levels in neutrophils of Parkinson disease patients.
- •Relevance of pRab levels as marker of PD.
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Krzysztof J. Gorgolewski Dan Lurie Sebastian Urchs Judy A. Kipping R. Cameron Craddock Michael P. Milham Daniel S. Margulies Jonathan Smallwood 《PloS one》2014,9(5)
Although neural activity often reflects the processing of external inputs, intrinsic fluctuations in activity have been observed throughout the brain. These may relate to patterns of self-generated thought that can occur while not performing goal-driven tasks. To understand the relationship between self-generated mental activity and intrinsic neural fluctuations, we developed the New York Cognition Questionnaire (NYC-Q) to assess the content and form of an individual''s experiences during the acquisition of resting-state fMRI data. The data were collected as a part of the Nathan Kline Rockland Enhanced sample. We decomposed NYC-Q scores using exploratory factor analysis and found that self-reported thoughts clustered into distinct dimensions of content (future related, past related, positive, negative, and social) and form (words, images, and specificity). We used these components to perform an individual difference analysis exploring how differences in the types of self-generated thoughts relate to whole brain measures of intrinsic brain activity (fractional amplitude of low frequency fluctuations, regional homogeneity, and degree centrality). We found patterns of self-generated thoughts related to changes that were distributed across a wide range of cortical areas. For example, individuals who reported greater imagery exhibited greater low frequency fluctuations in a region of perigenual cingulate cortex, a region that is known to participate in the so-called default-mode network. We also found certain forms of thought were associated with other areas, such as primary visual cortex, the insula, and the cerebellum. For example, individuals who reported greater future thought exhibited less homogeneous neural fluctuations in a region of lateral occipital cortex, a result that is consistent with the claim that particular types of self-generated thought depend on processes that are decoupled from sensory processes. These data provide evidence that self-generated thought is a heterogeneous category of experience and that studying its content can be helpful in understanding brain dynamics. 相似文献
6.
Sebastian Kalamajski Dominique Bihan Arkadiusz Bonna Kristofer Rubin Richard W. Farndale 《The Journal of biological chemistry》2016,291(15):7951-7960
The hallmark of fibrotic disorders is a highly cross-linked and dense collagen matrix, a property driven by the oxidative action of lysyl oxidase. Other fibrosis-associated proteins also contribute to the final collagen matrix properties, one of which is fibromodulin. Its interactions with collagen affect collagen cross-linking, packing, and fibril diameter. We investigated the possibility that a specific relationship exists between fibromodulin and lysyl oxidase, potentially imparting a specific collagen matrix phenotype. We mapped the fibromodulin-collagen interaction sites using the collagen II and III Toolkit peptide libraries. Fibromodulin interacted with the peptides containing the known collagen cross-linking sites and the MMP-1 cleavage site in collagens I and II. Interestingly, the interaction sites are closely aligned within the quarter-staggered collagen fibril, suggesting a multivalent interaction between fibromodulin and several collagen helices. Furthermore, we detected an interaction between fibromodulin and lysyl oxidase (a major collagen cross-linking enzyme) and mapped the interaction site to 12 N-terminal amino acids on fibromodulin. This interaction also increases the activity of lysyl oxidase. Together, the data suggest a fibromodulin-modulated collagen cross-linking mechanism where fibromodulin binds to a specific part of the collagen domain and also forms a complex with lysyl oxidase, targeting the enzyme toward specific cross-linking sites. 相似文献
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Kazuhiro Yamaguchi Klaus D. Jürgens Heinz Bartels Johannes Piiper 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1987,157(1):1-9
Summary To estimate the advantage of the small red blood cells (RBC) of high-altitude camelids for O2 transfer, the kinetics of O2 uptake into and release from the RBC obtained from llama, vicuña and alpaca were investigated at 37°C with a stopped-flow technique. O2 transfer conductance of RBC (G) was estimated from the rate of O2 saturation change and the corresponding O2 pressure difference between medium and hemoglobin. For comparison, O2 kinetics for the RBC of a lowaltitude camelid (dromedary camel) and the pygmy goat were determined and previously measured values for human RBC were used. O2 transfer of RBC was found to be strongly influenced by extracellular diffusion, except with O2 release into dithionite solutions of sufficiently high concentration (>30 mM). TheG values measured in these standard conditions,G
st (in mmol · min–1 · Torr–1 · (ml RBC)–1) were: high-altitude camelids, 0.58 (averaged for llama, alpaca and vicuña since there were no significant interspecific differences); camel 0.42; goat, 0.42; man, 0.39. The differences can in part be attributed to expected effects of the size and shape of the RBC (volume, surface area, mean thickness), as well as to the intracellular O2 diffusivity which depends on the concentration of cellular hemoglobin. The highG
st of RBC of highaltitude camelids may be considered to enhance O2 transfer in lungs and tissues. But the O2 transfer conductance of blood, , equal toG
st multiplied by hematocrit (in mmol · min–1 · Torr–1 · (ml blood)–1), was only slightly higher as compared to other species: 0.20 (llama, alpaca, vicuña), 0.14 (camel), 0.18 (goat), 0.17 (man).Abbreviations
DPG
2,3-diphosphoglycerate
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G
conductance
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Hb
hemoglobin
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RBC
red blood cells
-
percent saturation of hemoglobin 相似文献
10.
Karyometry and histometry of renal-cell carcinoma 总被引:1,自引:0,他引:1
M Bibbo H Galera-Davidson H E Dytch J Gonzalez de Chaves J Lopez-Garrido P H Bartels G L Wied 《Analytical and quantitative cytology and histology / the International Academy of Cytology [and] American Society of Cytology》1987,9(2):182-187
In an attempt to more objectively predict the outcome of renal cancers, karyometric and histometric studies were performed using an interactive computer-based system for the quantitative analysis of tissue sections. Analysis showed a significant relationship between patient survival and metastases and the histometric parameters of nuclear elongation, nuclear crowding and mitotic density, as well as tumor grade. Patients who died tended to have a high mitotic density, elongated and crowded nuclei and high-grade tumors. Ploidy showed no significant correlation with prognosis while nuclear elongation and crowding did. Differences in histologic grade were significantly associated with several histometric variables, including nuclear area, shape, crowding, elongation and mitotic density. 相似文献