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691.
Augusta Gaspar 《Acta ethologica》2006,9(1):1-14
Multiple dimensions of facial expression research are reviewed with emphasis in the study of species’ homology in both facial action single components and patterns or gestalten. Research over the last 30 years has revealed human universal patterns and some cross-species gestalten that appear as homologies. Recently, researchers are looking into the importance of individuality markers in facial behavior, which can play an important role in the fitness of individuals living in complex social systems and thus might be traceable in their evolutionary path. Chimpanzees, bonobos, and humans were in the center of most of this research with research results pointing toward homologies within the Homo–Pan clade. 相似文献
692.
Scent-marking behaviour of golden-faced saki monkey, Pithecia pithecia chrysocephala , was observed intermittently between 1987 and 1990 for a family group in a Central Amazonian forest fragment. Of 95 scent-marking events (during 275.5 hours of observation), throat-and-chest rubbing accounted for all except one anogenital rubbing. Nine of the throat-and-chest markings also involved touching groin with hands and eight markings (including the anogenital), urinating on the marked branch. Marking behaviour is strongly sex related, with the adult male making 88.4% of the markings. Scent-marking frequency by the adult male increased during breeding periods. Scent-marking behaviour seems related to courtship, and possibly stimulates sexual behaviour. All regularly marked spots consisted of horizontal branches on commonly travelled routes. Eleven occurred in feeding trees and lianas, but none in sleeping trees. Scent-marking behaviour in the monkeys studied here was not related to intergroup encounters and probably did not have a territorial function, although it may do so where different groups interact. 相似文献
693.
Oliver Pain Kylie P. Glanville Saskia P. Hagenaars Saskia Selzam Anna E. Fürtjes Hlna A. Gaspar Jonathan R. I. Coleman Kaili Rimfeld Gerome Breen Robert Plomin Lasse Folkersen Cathryn M. Lewis 《PLoS genetics》2021,17(5)
The predictive utility of polygenic scores is increasing, and many polygenic scoring methods are available, but it is unclear which method performs best. This study evaluates the predictive utility of polygenic scoring methods within a reference-standardized framework, which uses a common set of variants and reference-based estimates of linkage disequilibrium and allele frequencies to construct scores. Eight polygenic score methods were tested: p-value thresholding and clumping (pT+clump), SBLUP, lassosum, LDpred1, LDpred2, PRScs, DBSLMM and SBayesR, evaluating their performance to predict outcomes in UK Biobank and the Twins Early Development Study (TEDS). Strategies to identify optimal p-value thresholds and shrinkage parameters were compared, including 10-fold cross validation, pseudovalidation and infinitesimal models (with no validation sample), and multi-polygenic score elastic net models. LDpred2, lassosum and PRScs performed strongly using 10-fold cross-validation to identify the most predictive p-value threshold or shrinkage parameter, giving a relative improvement of 16–18% over pT+clump in the correlation between observed and predicted outcome values. Using pseudovalidation, the best methods were PRScs, DBSLMM and SBayesR. PRScs pseudovalidation was only 3% worse than the best polygenic score identified by 10-fold cross validation. Elastic net models containing polygenic scores based on a range of parameters consistently improved prediction over any single polygenic score. Within a reference-standardized framework, the best polygenic prediction was achieved using LDpred2, lassosum and PRScs, modeling multiple polygenic scores derived using multiple parameters. This study will help researchers performing polygenic score studies to select the most powerful and predictive analysis methods. 相似文献
694.
Villarreal Jesús Manuel Gutíerrez Armenta Jorge Alberto Gaspar 《Plasmonics (Norwell, Mass.)》2022,17(1):163-172
Plasmonics - We performed a quantitative study of the field intensity under surface plasmon (SP) using different impinging source changing the beam width for several metallic structures and compare... 相似文献
695.
696.
NaCl (0 to 274 mM) was added to the culture media of normal and habituated (auxin and cytokinin independent) sugarbeet calli
and its effect on growth (estimated by the increase of dry and organic matters), water content and osmotic potential was tested.
Growth of normal callus was stimulated by 68 mM NaCl after a lag period of two weeks. This callus tolerated up to 137 mM NaCl
without growth reduction and maintained its hydric status by readjustment of its osmotic potential in 24 h. NaCl quantities
under 34 mM stimulated growth of the habituated callus from the 3rd day on; higher NaCl concentrations (68 to 274 mM) inhibited
growth or were lethal. NaCl sensitivity of this habituated callus was not due to its inability to adjust its osmotic potential:
this adjustment occurred from the 4th h of culture whatever the media. From the 3rd day on, however, this callus presented
a water deficit which depended on NaCl concentration. It is suggested that the lowering of osmotic potential corresponds to
an important water loss in relation to changes in membrane permeability. This study finally shows that mechanisms of salt
tolerance may have developed at the cellular level. Lower growth and lower salt tolerance of the habituated callus need further
investigation in relation to cell structure and hormone autonomy.
相似文献
697.
698.
Minimal Deviation Hepatoma 7288 C cells were cultured in confluent layer with labeled stearic, oleic, linoleic and alpha-linolenic acids. The kinetics of incorporation and conversion to higher homologs was studied. The maximum amounts incorporated in nmoles per mg of cellular protein for stearic, oleic, linoleic and alpha-linolenic acids were 39, 115.6, 90 and 230 respectively. alpha-linolenic acid was converted to octadeca-6,9,12,15-tetraenoic acid (18:1), eicosa-11,14,17-trienoic acid (20:3), eicosa-8,11,14,17 and 5,11,14,17-tetraenoic acids (20:4) and eicosa-5,8,11,14,17-pentaenoic acid (20:5), and also to myristic, palmitic, palmitoleic, stearic and oleic acids. By a mathematical approach, the endogenous pool size of alpha-linolenic acid available for conversion to eicosa-5,8,11,14,17-pentaenoic acid, were calculated. Both values decreased when the cells were preincubated with unlabeled alpha-linolenic acid. 相似文献
699.
Elaine Stopforth Albert W. H. Neitz Anabella R. M. Gaspar 《Experimental & applied acarology》2010,51(4):309-325
A proteomics approach was employed to identify proteins secreted into the hemolymph of Ornithodorus savignyi ticks 2 h after immune-challenge with the yeast, Candida albicans. Profiling of the proteins present in hemolymph of unchallenged ticks versus ticks challenged with heat-killed yeast revealed
five proteins to be differentially expressed. The modulated protein spots were subjected to tandem mass spectrometry (MS/MS)
analysis, but could not be positively identified. These proteins can be assigned to the immune response as they were not induced
after aseptic injury. In an attempt to identify hemolymph proteins that recognize and bind to yeast cells, hemolymph obtained
from both unchallenged and challenged ticks was incubated with C. albicans. Elution of the bound proteins followed by SDS–PAGE analysis indicated that three proteins (97, 88 and 26 kDa) present in
both unchallenged and challenged hemolymph samples bind to yeast cells. The constant presence of these three proteins in tick
hemolymph leads us to believe that they may be involved in non-self recognition and participate in yeast clearance from tick
plasma. The analyzed yeast-binding proteins could also not be positively identified, suggesting that all the tick immune proteins
investigated in this study are novel. 相似文献
700.
Michelle J. Paddack John D. Reynolds Consuelo Aguilar Richard S. Appeldoorn Jim Beets Edward W. Burkett Paul M. Chittaro Kristen Clarke Rene Esteves Ana C. Fonseca Graham E. Forrester Alan M. Friedlander Jorge García-Sais Gaspar González-Sansón Lance K.B. Jordan David B. McClellan Margaret W. Miller Philip P. Molloy Peter J. Mumby Ivan Nagelkerken Isabelle M. Côté 《Current biology : CB》2009,19(7):590-595