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Cuthill IC 《Current biology : CB》2007,17(24):R1059-R1060
Cuttlefish are masters of disguise, rapidly changing colour to blend with their backgrounds. A new study shows that they break camouflage to direct warning messages at certain predators, but only those likely to be dissuaded by visual signals. 相似文献
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Food availability is often variable during the breeding season. Parents with nonmobile, altricial young have no choice but
to accept changes in local food availability, whereas in precocial animals, the parents may lead their young away from poor
sites to areas that have rich resources and/or are safe from predators. We investigated the latter hypotheses in the Kentish
plover Charadrius alexandrinus, a precocial shorebird that raises its young in two habitats: on lakeshore and in saltmarsh. Parents move with their broods
from saltmarsh to lakeshore, especially late in the breeding season, and we hypothesized that lakeshores provide more food
than the saltmarsh. Consistent with our hypotheses, plover chicks grew faster on the shore, and the difference in growth rates
between the two habitats was amplified later in the breeding season. In addition, brood survival was higher on lakeshore than
in saltmarsh and decreased with hatching date. Taken together, our results suggest that Kentish plover parents increase their
reproductive success by switching brood-rearing habitats strategically. 相似文献
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Laurens Pauwels Andrés Ritter Jonas Goossens Astrid Nagels Durand Hongxia Liu Yangnan Gu Jan Geerinck Marta Boter Robin Vanden Bossche Rebecca De Clercq Jelle Van Leene Kris Gevaert Geert De Jaeger Roberto Solano Sophia Stone Roger W. Innes Judy Callis Alain Goossens 《Plant physiology》2015,169(2):1405-1417
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R Gon?alves LA Szmuchrowski LS Prado BP Couto JCQ Machado VO Damasceno JA Lamounier 《Biology of sport / Institute of Sport》2015,32(3):255-260
The aim of this study was to assess the suitability of body mass index, waist circumference, waist-to-height ratio and aerobic fitness as predictors of cardiovascular risk factor clustering in children. A cross-sectional study was conducted with 290 school boys and girls from 6 to 10 years old, randomly selected. Blood was collected after a 12-hour fasting period. Blood pressure, waist circumference (WC), height and weight were evaluated according to international standards. Aerobic fitness (AF) was assessed by the 20-metre shuttle-run test. Clustering was considered when three of these factors were present: high systolic or diastolic blood pressure, high low-density lipoprotein (LDL) cholesterol, high triglycerides, high plasma glucose, high insulin concentrations and low high-density lipoprotein (HDL) cholesterol. A ROC curve identified the cut-off points of body mass index (BMI), WC, waist-to-height ratio (WHtR) and AF as predictors of risk factor clustering. BMI, WC and WHR resulted in significant areas under the ROC curves, which was not observed for AF. The anthropometric variables were good predictors of cardiovascular risk factor clustering in both sexes, whereas aerobic fitness should not be used to identify cardiovascular risk factor clustering in these children. 相似文献
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Hanan Shamseldin Anas?M. Alazami Melanie Manning Amal Hashem Oana Caluseiu Brahim Tabarki Edward Esplin Susan Schelley A.?Micheil Innes Jillian?S. Parboosingh Ryan Lamont CareRare Canada Consortium Jacek Majewski Francois?P. Bernier Fowzan?S. Alkuraya 《American journal of human genetics》2015,97(6):862-868
Primary microcephaly is a developmental brain anomaly that results from defective proliferation of neuroprogenitors in the germinal periventricular zone. More than a dozen genes are known to be mutated in autosomal-recessive primary microcephaly in isolation or in association with a more generalized growth deficiency (microcephalic primordial dwarfism), but the genetic heterogeneity is probably more extensive. In a research protocol involving autozygome mapping and exome sequencing, we recruited a multiplex consanguineous family who is affected by severe microcephalic primordial dwarfism and tested negative on clinical exome sequencing. Two candidate autozygous intervals were identified, and the second round of exome sequencing revealed a single intronic variant therein (c.2885+8A>G [p.Ser963∗] in RTTN exon 23). RT-PCR confirmed that this change creates a cryptic splice donor and thus causes retention of the intervening 7 bp of the intron and leads to premature truncation. On the basis of this finding, we reanalyzed the exome file of a second consanguineous family affected by a similar phenotype and identified another homozygous change in RTTN as the likely causal mutation. Combined linkage analysis of the two families confirmed that RTTN maps to the only significant linkage peak. Finally, through international collaboration, a Canadian multiplex family affected by microcephalic primordial dwarfism and biallelic mutation of RTTN was identified. Our results expand the phenotype of RTTN-related disorders, hitherto limited to polymicrogyria, to include microcephalic primordial dwarfism with a complex brain phenotype involving simplified gyration. 相似文献
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David Gendron Anne-Marie Lemay Claudine Tremblay Laetitia JA Lai Anick Langlois émilie Bernatchez Nicolas Flamand Marie-Renée Blanchet Anthony S Don Ynuk Bossé élyse Bissonnette David Marsolais 《Respiratory research》2015,16(1)