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991.
Alexandre Roulin Amélie N. Dreiss Mathias Kölliker 《Ethology : formerly Zeitschrift fur Tierpsychologie》2010,116(9):787-796
Consistent inter‐individual variation in behaviour over time and across contexts has been reported for a wide variety of animals, a phenomenon commonly referred to as personality. As behavioural patterns develop inside families, rearing conditions could have lasting effects on the expression of adult personality. In species with parental care, conflicts among family members impose selection on parental and offspring behaviour through coadaptation. Here, we argue that the interplay between the evolution of personality traits (i.e. boldness, exploration, activity, aggressiveness and sociability) expressed outside the family context and the specialized behaviours expressed inside families (i.e. offspring begging behaviour and parental response to offspring solicitations) can have important evolutionary consequences. Personality differences between parents may relate to the typically observed variation in the way they respond to offspring demand, and dependent offspring may already express personality differences, which may relate to the way they communicate with their parents and siblings. However, there has been little research on how personality relates to parental and offspring behaviours. Future research should thus focus on how and why personality may be related to the specialized parent and offspring behaviour that evolved as adaptations to family life. 相似文献
992.
Alexandre M. J. J. Bonvin J. Antoon C. Rullmann Rolf M. J. N. Lamerichs Rolf Boelens Robert Kaptein 《Proteins》1993,15(4):385-400
The structure in solution of crambin, a small protein of 46 residues, has been determined from 2D NMR data using an iterative relaxation matrix approach (IRMA) together with distance geometry, distance bound driven dynamics, molecular dynamics, and energy minimization. A new protocol based on an “ensemble” approach is proposed and compared to the more standard initial rate analysis approach and a “single structure” relaxation matrix approach. The effects of fast local motions are included and R-factor calculations are performed on NOE build-ups to describe the quality of agreement between theory and experiment. A new method for stereospecific assignment of prochiral groups, based on a comparison of theoretical and experimental NOE intensities, has been applied. The solution structure of crambin could be determined with a precision (rmsd from the average structure) of 0.7 Å on backbone atoms and 1.1 Å on all heavy atoms and is largely similar to the crystal structure with a small difference observed in the position of the side chain of Tyr-29 which is determined in solution by both J-coupling and NOE data. Regions of higher structural variability (suggesting higher mobility) are found hi the solution structure, in particular for the loop between the two helices (Gly-20 to Pro-22). © 1993 Wiley-Liss, Inc. 相似文献
993.
Pierre Bize Aurélie Klopfenstein Caroline Jeanneret Alexandre Roulin 《Journal of Ornithology》2007,148(4):387-393
The Alpine swift (Apus melba) forages on insects caught exclusively on the wing, implying that dependent nestlings face acute food shortage in periods
of cold and rainy weather. Therefore, there should be strong selection on nestling swifts to evolve physiological strategies
to cope with periods of undernutrition. We have investigated intra-individual changes in nestling pectoral muscle and body
temperature in response to a 1-week period of inclement weather. The pectoral muscle is the largest reserves of proteins,
and nestlings have to devote a large amount of energy in the maintenance of body temperature. The results show that nestling
pectoral muscle size and body temperature were significantly reduced during the episode of inclement weather. Assuming that
these physiological changes are adaptive, our study suggests that nestling swifts spare energy by a pronounced reduction (up
to 18°C) in body temperature and use proteins from the pectoral muscle as a source of extra energy to survive prolonged periods
of fasting. 相似文献
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Stevenson D Revie J Chase JG Hann CE Shaw GM Lambermont B Ghuysen A Kolh P Desaive T 《Biomedical engineering online》2012,11(1):28
ABSTRACT: INTRODUCTION: : Cardiac elastances are highly invasive to measure directly, but are clinically useful due to the amount of information embedded in them. Information about the cardiac elastance, which can be used to estimate it, can be found in the downstream pressure waveforms of aortic pressure (Pao) and the pulmonary artery (Ppa). However these pressure waveforms are typically noisy and biased, and require processing in order to locate the specific information required for the cardiac elastance estimation. This paper presents the method to algorithmically process the pressure waveforms. METHOD: S: A shear transform is developed in order to help locate information in the pressure waveforms. This transform turns difficult to locate corners into easy to locate maximum or minimum points as well as providing error correction. RESULTS: : The method located all points 87 out of 88 waveforms for Ppa to within the sampling frequency. For Pao, out of 616 total points, 605 were found within 1%, 5 within 5%, 4 within 10% and 2 within 20%. CONCLUSIONS: : The presented method provides a robust, accurate and dysfunction independent way to locate points on the aortic and pulmonary artery pressure waveforms, allowing the non-invasive estimation of the left and right cardiac elastance. 相似文献
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Cristiane C. C. Teixeira Elias de Paiva Junior Luis Alexandre Pedro de Freitas 《AAPS PharmSciTech》2018,19(3):1061-1071
Curcumin is the main bioactive component of Curcuma longa L. and has recently aroused growing interest from the scientific community. Unfortunately, the medicinal properties attributed to curcuminoids are impaired by their low oral bioavailability or low solubility in aqueous solutions. Many strategies have been studied to improve curcumin solubility; however, the preparation of granules using hydrophilic materials has never been attempted. The aim of this work was to develop curcumin granules by fluidized bed hot-melt granulation using the hydrophilic carrier Gelucire® 50:13. A two-level factorial design was used to verify the influence of Gelucire® 50:13 and lactose contents found in the granules on their size, morphology, bulk and tapped densities, flow, moisture content, and water activity. The granules obtained were also evaluated by differential scanning calorimetry, thermogravimetric analysis, X-ray powder diffraction, and infrared spectrometry. The curcumin solubility and dissolution rates in water were determined by liquid chromatography. The best formulation provides an increase of curcumin solubility of 4642-fold and 3.8-fold compared to the physical mixture. The dissolution tests showed a maximum drug release from granules after 45 min of 70% at pH 1.2 and 80% at pH 5.8 and 7.4, while for non-granulated curcumin, the release was below 20% in all pH. The solid-state characterization and solubility measurement showed good stability of granules over 9 months. The results attest that the fluidized bed hot-melt granulation with hydrophilic binders is an attractive and promising alternative to obtain solid forms of curcumin with enhanced bioavailability. 相似文献