Solvation of Ions. II. Use of a Variable Solvation Number for K+

Gibbs free energies of transfer of K(I) ion from water to water-dimethyl sulfoxide mixtures corrected to zero ionic strength have been used to deduce information concerning states of solvation of K+ ion in the purely aqueous phase and in the mixed solvent phase. It was found that the largest number of water molecules which needed to be assigned to the solvent cage of K+ was 11 in either phase. The partition equilibrium constant, /?0, for the distribution of K(H20)H+ between the two phases was found as a function of the mole fraction of dimethyl sulfoxide in the mixed solvent phase. The largest number of dimethyl sulfoxide molecules which needed to be assigned to the solvent cage was 10. The number of solvent molecules in the solvent cage was allowed to be variable and the overall formation constants of all K(H20)j((CH3)2S0)k+ ions contributing to the free energy of transfer were determined. The results are compared with the results from molecular dynamics computer simulations for K+ where possible

Emerging genotype-phenotype relationships in primary ciliary dyskinesia

Primary ciliary dyskinesia (PCD) is a rare inherited condition affecting motile cilia and leading to organ laterality defects, recurrent sino-pulmonary infections, bronchiectasis, and severe lung disease. Research over the past twenty years has revealed variability in clinical presentations, ranging from mild to more severe phenotypes. Genotype and phenotype relationships have emerged. The increasing availability of genetic panels for PCD continue to redefine these genotype-phenotype relationships and reveal milder forms of disease that had previously gone unrecognized

Hox-logic of preadaptations for social insect symbiosis in rove beetles

How symbiotic lifestyles evolve from free-living ecologies is poorly understood. Novel traits mediating symbioses may stem from preadaptations: features of free-living ancestors that predispose taxa to engage in nascent interspecies relationships. In Metazoa's largest family, Staphylinidae (rove beetles), the body plan within the subfamily Aleocharinae is preadaptive for symbioses with social insects. Short elytra expose a pliable abdomen that bears targetable glands for host manipulation or chemical defense. The exposed abdomen has also been convergently refashioned into ant- and termite-mimicking shapes in multiple symbiotic lineages. Here we show how this preadaptive anatomy evolved via novel Hox gene functions that remodeled the ancestral coleopteran groundplan. Using the model staphylinid Dalotia coriaria, we abolished activities of the five thoracic and abdominal Hox genes. We show that elytral shortening is a staphylinid-specific property of the Hox-less appendage ground state, which is overridden in the metathorax by Ultrabithorax to promote hind wing expansion. In the exposed abdomen, we present evidence that defensive gland development stems from novel combinatorial outputs of the Abdominal-A and Abdominal-B Hox proteins: in the posterior compartment of tergite VI they specify a chemical gland reservoir, an imaginal disc-like invagination of ectodermal secretory cells; in the anterior compartment of tergite VII Abdominal-A and Abdominal-B specify clusters of classical duct-bearing glands. These distinct gland cell types collectively synthesize a blend of benzoquinone irritants, surfactant esters and alkane solvent, a defensive chemistry, which in symbiotic species has been augmented with specialized volatiles that potently manipulate ant behavior. These results reveal how Hox-controlled body axis modifications caused a convergent trend towards evolving symbiosis in the Metazoa

Chimpanzees demonstrate individual differences in social information use

Studies of transmission biases in social learning have greatly informed our understanding of how behaviour patterns may diffuse through animal populations, yet within-species inter-individual variation in social information use has received little attention and remains poorly understood. We have addressed this question by examining individual performances across multiple experiments with the same population of primates. We compiled a dataset spanning 16 social learning studies (26 experimental conditions) carried out at the same study site over a 12-year period, incorporating a total of 167 chimpanzees. We applied a binary scoring system to code each participant’s performance in each study according to whether they demonstrated evidence of using social information from conspecifics to solve the experimental task or not (Social Information Score—‘SIS’). Bayesian binomial mixed effects models were then used to estimate the extent to which individual differences influenced SIS, together with any effects of sex, rearing history, age, prior involvement in research and task type on SIS. An estimate of repeatability found that approximately half of the variance in SIS was accounted for by individual identity, indicating that individual differences play a critical role in the social learning behaviour of chimpanzees. According to the model that best fit the data, females were, depending on their rearing history, 15–24% more likely to use social information to solve experimental tasks than males. However, there was no strong evidence of an effect of age or research experience, and pedigree records indicated that SIS was not a strongly heritable trait. Our study offers a novel, transferable method for the study of individual differences in social learning

The Environmental Context and Function of Burnt-Mounds : New Studies of Irish Fulachtaí Fiadh

The authors acknowledge funding from The Leverhulme Trust (F/00144/AI) and assistance from a large number of individuals including; Margaret Gowen (access to sites and assistance throughout),A. Ames, H, Essex (pollen processing), S. Rouillard & R. Smith (illustrations), C. McDermott, S. Bergerbrandt, all the staff of Margaret Gowen & Co. Ltd, TVAS Ireland and CRDS. Excavation works and some post-excavation analysis was paid for my Bord Gáis and the National Roads Authority (now Transport Infrastructure Ireland). Thanks also to David Smith for access to the Maureen Girling collection and assistance with identifications.Peer reviewedPostprintPostprin

Characterizing and Diminishing Autofluorescence in Formalin-fixed Paraffin-embedded Human Respiratory Tissue

The article of record as published may be found at http://dx.doi.org/10.1369/0022155414531549Tissue autofluorescence frequently hampers visualization of immunofluorescent markers in formalin-fixed paraffin-embedded respiratory tissues. We assessed nine treatments reported to have efficacy in reducing autofluorescence in other tissue types. The three most efficacious were Eriochrome black T, Sudan black B and sodium borohydride, as measured using white light laser confocal Ʌ² (multi-lambda) analysis. We also assessed the impact of steam antigen retrieval and serum application on human tracheal tissue autofluorescence. Functionally fitting this Ʌ² data to 2-dimensional Gaussian surfaces revealed that steam antigen retrieval and serum application contribute minimally to autofluorescence and that the three treatments are disparately efficacious. Together, these studies provide a set of guidelines for diminishing autofluorescence in formalin-fixed paraffin-embedded human respiratory tissue. Additionally, these characterization techniques are transferable to similar questions in other tissue types, as demonstrated on frozen human liver tissue and paraffin-embedded mouse lung tissue fixed in different fixatives.NIHNIAI