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991.
Externally attached radio transmitters do not affect the parental care behaviour of rock bass 总被引:2,自引:0,他引:2
S. J. Cooke 《Journal of fish biology》2003,62(4):965-970
Turning, pectoral fin and caudal fin rates and time spent on the nest of male rock bass Ambloplites rupestris , engaged in parental care, were not affected after the attachment of external radio transmitters. Reproductive success was similar between treatment and control fish. Micro external radio transmitters can be used on small fishes for studying parental care duration and post-care movement without altering their behaviour. 相似文献
992.
993.
Brunner RM Srikanchai T Murani E Wimmers K Ponsuksili S 《Molecular biology reports》2012,39(1):97-107
Six genes that were known to exhibit expression levels that are correlated to drip loss BVES, SLC3A2, ZDHHC5, CS, COQ9, and
EGFR have been for candidate gene analysis. Based on in silico analysis SNPs were detected, confirmed by sequencing, and used for genotyping. The SNPs were genotyped in about 1,800 animals
from six pig populations including commercial herds of Pietrain (PI) and German Landrace (DL), different commercial herds
of Pietrain × (German Large White × German Landrace) (PIF1(a/b/c)), and one experimental F2-population Duroc × Pietrain (DUPI). Comparative and genetic mapping established the location of BVES on SSC1, of SLC3A2 and
ZDHHC5 on SSC2, of CS on SSC5, of COQ9 on SSC6 and of EGFR on SSC9, respectively, coinciding with QTL regions for carcass
and meat quality traits. BVES, SLC3A2, and CS revealed association at least with drip loss and with several other measures
of water holding capacity (WHC). Moreover, COQ9 and EGFR were associated with several meat quality traits such as meat color
and/or thawing loss. This study reveals statistic evidence in addition to the functional relationship of these genes to WHC
previously evidenced by expression analysis. This study reveals positional and genetic statistical evidence for a link of
genetic variation at these loci or close to them and promotes those six candidate genes as functional and/or positional candidate
genes for meat quality traits. 相似文献
994.
Scott A. Kleiner 《Biology & philosophy》1999,14(1):55-63
Thomas Nickles challenges my thesis that innovative discoveries can be based on deliberately chosen problems and research strategies. He suggests that all significant innovation can be seen as such only in retrospect and that its generation must be serendipitous. Here I argue in response that significant innovations can and do often arise from self conscious critical appraisal of orthodox practice combined with regulated though speculative abductive argumentation to alternative explanatory schemata. Orthodox practice is not based upon monolithic systems of belief about the subject of inquiry. Rather major domains of scientific practice often are approached from different conceptualizations that provide grounds for critical dialectic and consilient empirical information. Abductive arguments that meet appropriate conditions of likelihood, probability and analogy are an important means of justifying allocating resources to innovative practices that have yet to produce products that can rival those of established orthodoxy. 相似文献
995.
A. Klockow-Beck A. Nick St. Geisshuesler D. Schaufelberger 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1998,720(1-2):141-151
A capillary electrophoresis (CE) method has been developed as an alternative method for the determination of the inorganic degradation products sulfate and sulfamate in topiramate drug product and drug substance, currently performed by ion chromatography. The anions are separated in a background electrolyte containing potassium chromate and boric acid, followed by indirect UV detection. By adding tetradecyltrimethylammonium bromide to the electrolyte, analysis is performed under co-electroosmotic flow conditions. Variations in injection volumes and migration times are compensated for by use of an internal standard. The validation of the method, which was performed according to ICH guidelines (International Conference on Harmonization of Technical Requirements for Registration of Pharmaceuticals for Human Use) [1], comprises specificity, accuracy, linearity, precision, sensitivity and robustness. In addition, the results of an actual tablet sample analysis obtained by this CE method are statistically shown to be in close agreement with those obtained by an ion chromatographic method. 相似文献
996.
S. P. Kharitonov D. E. Nowak A. I. Nowak N. A. Egorova S. A. Korkina D. V. Osipov O. V. Natal’skaya 《Biology Bulletin》2009,36(5):469-478
Red-breasted goose colonies have been studied near Medusa Bay (73°21′N, 80°32′E), on the northwestern Taimyr Peninsula, and
along the Agapa River (70°11′N, 86°15′E) down to its mouth (71°26′N, 89° 13′E), in the central Taimyr Peninsula. Red-breasted
geese nesting near peregrine falcons are protected by the falcons from arctic foxes; however, they are sometimes attacked
by the falcons themselves. In the colonies near peregrine falcon nests, the vast majority of goose nests were situated no
farther than 100 m from the falcon nest. When food is abundant, falcons protect a larger area around their nest. The distance
between the falcon nest and the surrounding goose nests is inversely related to the falcon’s activity. In years of higher
falcon activity, falcons prevent red-breasted geese from nesting as close to their nest as in years of lower falcon activity.
Additional stimuli are required for red-breasted geese to form colonies near rough-legged buzzard nests. The distance between
snowy owl nests and red-breasted goose nests was smaller when arctic foxes were abundant than when they were scarce. 相似文献
997.
998.
N. P. Krivosheina 《Biology Bulletin》2012,39(3):250-257
The composition of seven dipteran families from the complex of larvae dwelling in sandy soils of the southeastern Karakum Desert, represented by both free-living soil forms and endobionts ecologically dependent mainly on herbaceous plants, is analyzed. In the surface horizons of the soil, at a depth of up to 20 cm, free-living soil-dwellers form a stable complex, which includes saprophagous coleopteran larvae and their constant companions, the obligatorily predaceous dipteran larvae. Previously unknown data on the lifestyle of the larvae of five therevid genera are given. 相似文献
999.
A. Gumbert J. Kunze L. Chittka 《Proceedings. Biological sciences / The Royal Society》1999,266(1429):1711
Evolutionary biologists have long hypothesized that the diversity of flower colours we see is in part a strategy to promote memorization by pollinators, pollinator constancy, and therefore, a directed and efficient pollen transfer between plants. However, this hypothesis has never been tested against a biologically realistic null model, nor were colours assessed in the way pollinators see them. Our intent here is to fill these gaps. Throughout one year, we sampled floral species compositions at five ecologically distinct sites near Berlin, Germany. Bee-subjective colours were quantified for all 168 species. A model of colour vision was used to predict how similar the colours of sympatric and simultaneously blooming flowers were for bees. We then compared flower colour differences in the real habitats with those of random plant communities. We did not find pronounced deviations from chance when we considered common plants. When we examined rare plants, however, we found significant divergence in two of the five plant communities. At one site, similarly coloured species were found to be more frequent than expected, and at the other two locations, flower colours were indistinguishable from a random distribution. These results fit theoretical considerations that rare plants are under stronger selective pressure to secure pollination than common plants. Our study illustrates the power of linking such distinct biological traditions as community ecology and the neuroethology of bee vision. 相似文献
1000.