Several hypotheses have been proposed to explain the mechanisms responsible for maintenance of host-specific gentes in the common cuckoo (Cuculus canorus). Some of them expect that when adult cuckoos return to lay their eggs to their natal site (natal philopatry hypothesis) or habitat in which they were reared (habitat-imprinting hypothesis), there is a higher probability of finding nests of the host species by which they were reared. Since published evidence is ambiguous, we here evaluate the natal philopatry and habitat-imprinting hypotheses using information on habitat homogeneity and cross-continental long-term ringing data. We found no evidence for the natal philopatry hypothesis-instead of returning to their natal site, juvenile cuckoos exhibited longer dispersal movements than adults, and the difference was even larger in comparison with a wide array of cuckoo host species. On the contrary, we found support for the habitat-imprinting hypothesis-juvenile cuckoos followed similar levels of natal habitat homogeneity at 5- and 25-km scale when returning to breed in the next years. Our results suggest that preference for the particular habitat structures may help cuckoos to find appropriate hosts.The concept of secondary bond covers a wide range of non-covalent interactions involving an acceptor (or electrophilic) molecule and an electron donor (or nucleophilic) one. It involves triel, tetrel, pnictogen, chalcogen, halogen, and aerogen bonds as well as hydrogen bonds. Such interactions yield complexes in which the internuclear distance of the electrophilic and nucleophilic centers is intermediate between the sums of the covalent and van der Waals radii of these atoms. These complexes can be considered as precursors of hypothetical nucleophilic substitution or addition reactions. As a consequence of the least motion principle, in the complex, the arrangement of the ligands around the electrophilic center should look like that of the hypothetical transition state or addition product.  https://www.selleckchem.com/products/AZD2281(Olaparib).html  In a same fashion, the geometry around the nucleophilic center is determined by the location of the lone pair or of the bond involved in the interaction. In this picture of secondary bonding, the structure of the valence shell of the electrophilic atoms determines the geometry of the complex rather than the group to which belongs the elemental atom. The reorganization of the complexes in terms of the arrangement of the bonding and non-bonding electronic domains around the electrophilic center enables to rationalize the geometries in a systematic fashion. A set of VSEPR inspired rules enabling the building up of secondary bonded isomers are proposed and checked by quantum chemical calculations performed on representative test systems of the AX4-nEn type. Graphical Abstract An example of secondary interaction FClO[Formula see text].OBJECTIVE The accuracy of phase-contrast magnetic resonance imaging (PC-MRI) measurement is investigated using a computational fluid dynamics (CFD) model with the objective to determine the magnitude of the flow underestimation due to turbulence behind a narrowed valve in a phantom experiment. MATERIALS AND METHODS An acrylic stationary flow phantom is used with three insertable plates mimicking aortic valvular stenoses of varying degrees. Positive and negative horizontal fluxes are measured at equidistant slices using standard PC-MRI sequences by 1.5T and 3T systems. The CFD model is based on the 3D lattice Boltzmann method (LBM). The experimental and simulated data are compared using the Bland-Altman-derived limits of agreement. Based on the LBM results, the turbulence is quantified and confronted with the level of flow underestimation. RESULTS LBM gives comparable results to PC-MRI for valves up to moderate stenosis on both field strengths. The flow magnitude through a severely stenotic valve was underestimated due to signal void in the regions of turbulent flow behind the valve, consistently with the level of quantified turbulence intensity. DISCUSSION Flow measured by PC-MRI is affected by noise and turbulence. LBM can simulate turbulent flow efficiently and accurately, it has therefore the potential to improve clinical interpretation of PC-MRI.Memory is always vulnerable to loss because it fades over time. To avoid the potential loss of a particular memory, individuals who can anticipate this loss might seek an opportunity to re-encode the information at the later point. Evidence shows that animals engage in online memory monitoring, but few studies have addressed whether they seek information prospectively to guard against potential forgetting. In the present study, to address this issue three capuchin monkeys were tested using a delayed matching-to-sample task with a cue signaling delay length (short or long). In the tests, subjects could choose at the onset of the delay whether or not to seek a re-presentation of a sample after the delay. Results showed that two monkeys sought re-presentation in the long delay more frequently than in the short delay, suggesting knowledge of the necessity of re-presentation based on knowing the length of the delay. However, further tests provided no evidence that this response was based on metacognitive cues. Whether capuchin monkeys are capable of prospective information-seeking for own potential forgetting remains to be established.Primates maintain social bonds with specific individuals in the group by directing grooming toward them. Social grooming is often targeted toward individuals with whom the most benefits can be exchanged, which are usually the high-ranking individuals. We used the Seyfarth model to investigate whether dominance rank alters the distribution of grooming in a group of Macaca fascicularis umbrosus at Great Nicobar Island. We investigated whether dominance rank predicted grooming rate in both males and females. We used social network analysis to examine whether high-ranking animals maintain a central position in the grooming network. We also investigated whether adult individuals exchange grooming for social tolerance, as indicated by physical proximity. We found that more social grooming was directed toward high-ranking females, but not high-ranking males. Social network analysis suggested that high-ranking animals are not central individuals in the distribution of grooming; rather, middle-ranking animals were major contributors to the distribution of grooming.