The binding of phosphate to tripodal metalloreceptors 1 and 2 is reported. Receptors 1 and 2 are C3v symmetric, designed to complement three sides of a tetrahedron. The receptors derive from tripodal ligands that are preorganized through binding to a central Cu(II) atom. These metalloreceptors demonstrate high selectivity and affinity for the molecular recognition of phosphate in aqueous media at neutral pH. The binding of phosphate and other anions to the cavities of receptors 1 and 2 was monitored by UV/vis titration techniques. Binding algorithms were used to determine the affinity of phosphate to 1 and 2 with association values (Ka) of 2.5 x 104 and 1.5 x 104 M-1, respectively.
SummaryFtsZ is required throughout the cell division process in eubacteria and in archaea. We report the isolation of novel mutants of the FtsZ gene in Caulobacter crescentus. Clusters of charged amino acids were changed to alanine to minimize mutations that affect protein folding. Molecular modelling indicated that all the clustered-charged-to-alanine mutations had altered amino acids at the surface of the protein. Of 13 such mutants, four were recessive-lethal, three were dominant-lethal, and six had no discernible phenotype. An FtsZ depletion strain of Caulobacter was constructed to analyse the phenotype of the recessive-lethal mutations and used to show that they blocked cell division at distinct stages. One mutation blocked the initiation of cell division, two mutations blocked cell division randomly, and one mutation blocked both early and late stages of cell division. The effect of the recessive mutations on the subcellular localization of FtsZ was determined. Models to explain the various mutant phenotypes are discussed. This is the first set of recessive alleles of ftsZ blocked at different stages of cell division.
The relative age effect (RAE) describes an overrepresentation of players born early (Q1) in a selection year and is highly prevalent within youth sport pathways. However, a dearth of research has investigated the RAE at the "super-elite" level. The present research assessed the presence of RAE in super-elite performers. Study 1 investigated RAEs in the world's best international Test cricketers (N = 262) over a 20-year period according to a robust and stringent "super-elite" criteria. Results revealed the RAE (Q1) when all disciplines were combined. Upon closer examination, this effect was also observed for the batting and spin bowling disciplines, whereas no RAE was found for the pace bowling discipline. Study 2 investigated RAEs in super-elite rugby union players (N = 691) over a 20 year period. Results revealed the RAE for backs (Q1) and a reversal of the traditional RAE (Q4) for forwards, and when all rugby union positions were combined. These findings provide new evidence of RAEs at the super-elite level and present both inter and intra sports differences. Potential explanations for these findings are explored, owing to the survival and evolution of the fittest concepts, and the implications for future research and applied practice are presented.
Despite a plethora of research on moral disengagement and antisocial behavior, there is a dearth of literature that explores personality in the context of these undesirable attitudes and behaviors. We provide the first examination of personality, specifically narcissism, as a predictor of moral disengagement and antisocial behavior in sport. Given that narcissism is negatively related to empathy and positively related to feelings of entitlement, it is more likely for narcissists to disengage morally and to behave antisocially. We thus hypothesized that narcissism would predict antisocial behavior via moral disengagement. Across 12 team contact sports (n = 272), bootstrapped mediation analyses confirmed this indirect effect, which remained significant when controlling for motivational climate, social desirability, sex and sport type. Coaches and practitioners would do well to consider the darker side of personality in targeting moral disengagement and its behavioral consequences in team sports.
The iconic Ho'oumi Beach site Nuku Hiva Island (Marquesas), was excavated by Robert Suggs in the late 1950s. It figured importantly in his island-wide reconstruction of settlement patterns, socio-political organisation, material culture and subsistence change -a cultural historical framework that has guided Marquesan archaeology for six decades. Ho'oumi is also one of four Marquesan localities where prehistoric ceramics have been found. We revisited Ho'oumi to acquire chronological and palaeoenvironmental context for two cultural occupations reported by Suggs. Eight 14 C determinations on short-lived materials and new marine reservoir corrections are reported, and the overall series evaluated using Bayesian modelling. A single ceramic sherd, previously assigned to a Fijian source, is attributed to the thirteenth to fourteenth centuries AD -a period when Marquesans engaged in long-distance voyaging. A significant marine inundation disrupted the associated occupation, leading to sustained coastal abandonment. Stratigraphic and historical evidence suggests this was a palaeotsunami, which may also be represented at Hane (Ua Huka Island). House pavements of the early occupation were replaced by raised megalithic house foundations, probably around the late seventeenth to mid-eighteenth centuries AD, but material culture changes were modest. By late prehistory, mature native forest was largely replaced by secondary species and Polynesian introductions.
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