1,645 research outputs found
Conceptual design study of advanced acoustic composite nacelle
Conceptual nacelle designs for wide-bodied and for advanced-technology transports were studied with the objective of achieving significant reductions in community noise with minimum penalties in airplane weight, cost, and in operating expense by the application of advanced composite materials to nacelle structure and sound suppression elements. Nacelle concepts using advanced liners, annular splitters, radial splitters, translating centerbody inlets, and mixed-flow nozzles were evaluated and a preferred concept selected. A preliminary design study of the selected concept, a mixed flow nacelle with extended inlet and no splitters, was conducted and the effects on noise, direct operating cost, and return on investment determined
Erratum: Wally, Z.J.; van Grunsven, W.; Claeyssens, F.; Goodall, R.; Reilly, G.C. Porous Titanium for Dental Implant Applications. Metals 2015, 5, 1902â1920.
The authors wish to make the following corrections to the citations in the published paper [1].[...
Treatment of diseases : a short treatise to secure advancement in the science of medicine
Integration of microRNA signatures of distinct mammary epithelial cell types with their gene expression and epigenetic portraits
Introduction: MicroRNAs (miRNAs) have been implicated in governing lineage specification and differentiation in multiple organs; however, little is known about their specific roles in mammopoiesis. We have determined the global miRNA expression profiles of functionally distinct epithelial subpopulations in mouse and human mammary tissue, and compared these to their cognate transcriptomes and epigenomes. Finally, the human miRNA signatures were used to interrogate the different subtypes of breast cancer, with a view to determining miRNA networks deregulated during oncogenesis. Methods: RNA from sorted mouse and human mammary cell subpopulations was subjected to miRNA expression analysis using the TaqMan MicroRNA Array. Differentially expressed (DE) miRNAs were correlated with gene expression and histone methylation profiles. Analysis of miRNA signatures of the intrinsic subtypes of breast cancer in The Cancer Genome Atlas (TCGA) database versus those of normal human epithelial subpopulations was performed. Results: Unique miRNA signatures characterized each subset (mammary stem cell (MaSC)/basal, luminal progenitor, mature luminal, stromal), with a high degree of conservation across species. Comparison of miRNA and transcriptome profiles for the epithelial subtypes revealed an inverse relationship and pinpointed key developmental genes. Interestingly, expression of the primate-specific miRNA cluster (19q13.4) was found to be restricted to the MaSC/basal subset. Comparative analysis of miRNA signatures with H3 lysine modification maps of the different epithelial subsets revealed a tight correlation between active or repressive marks for the top DE miRNAs, including derepression of miRNAs in Ezh2-deficient cellular subsets. Interrogation of TCGA-identified miRNA profiles with the miRNA signatures of different human subsets revealed specific relationships. Conclusions: The derivation of global miRNA expression profiles for the different mammary subpopulations provides a comprehensive resource for understanding the interplay between miRNA networks and target gene expression. These data have highlighted lineage-specific miRNAs and potential miRNA-mRNA networks, some of which are disrupted in neoplasia. Furthermore, our findings suggest that key developmental miRNAs are regulated by global changes in histone modification, thus linking the mammary epigenome with genome-wide changes in the expression of genes and miRNAs. Comparative miRNA signature analyses between normal breast epithelial cells and breast tumors confirmed an important linkage between luminal progenitor cells and basal-like tumors.Bhupinder Pal, Yunshun Chen, Andrew Bert, Yifang Hu, Julie M. Sheridan, Tamara Beck, Wei Shi, Keith Satterley, Paul Jamieson, Gregory J. Goodall, Geoffrey J. Lindeman, Gordon K. Smyth, and Jane E. Visvade
Generalized partially linear models on Riemannian manifolds
We introduce generalized partially linear models with covariates on Riemannian manifolds. These models, like ordinary generalized linear models, are a generalization of partially linear models on Riemannian manifolds that allow for scalar response variables with error distribution models other than a normal distribution. Partially linear models are particularly useful when some of the covariates of the model are elements of a Riemannian manifold, because the curvature of these spaces makes it difficult to define parametric models. The model was developed to address an interesting application: the prediction of children's garment fit based on threeâdimensional scanning of their bodies. For this reason, we focus on logistic and ordinal models and on the important and difficult case where the Riemannian manifold is the threeâdimensional case of Kendall's shape space. An experimental study with a wellâknown threeâdimensional database is carried out to check the goodness of the procedure. Finally, it is applied to a threeâdimensional database obtained from an anthropometric survey of the Spanish child population. A comparative study with related techniques is carried out
Effects of mountain gorilla foraging activities on the productivity of their food plant species
Mountain gorillas subsist principally on foliage from the dense herbaceous understorey that is found throughout most of their habitat in the Virunga Volcanoes region. Their foraging activities cause considerable structural damage to this vegetation. Those plant species that are quantitatively most important in the gorillas' diet respond to this damage by increasing primary productivity. At a sample of spots at which gorillas had fed, these species showed significantly higher growth rates over a 6-month interval than they did at nearby spots that had not been touched by the gorillas. Stem densities of herbaceous food species at feeding spots increased markedly both in comparison to their original values and to values for the same species at untouched spots. As a result, spots at which gorillas have fed are likely to become very attractive as future feeding spots. It is unlikely that gorillas âmanageâ their habitat in any specific fashion, largely because they do not have exclusive use of their home ranges. Their activities appear to maintain habitat productivity over the short term, on a time scale relevant to patterns of area revisits by social groups, and may contribute to long term beneficial alterations of regularly used areas, however. Effects of the type reported here may have been an important aspect of the adaptation by gorillas to terrestrial folivory. RĂSUMEĂ Les gorilles de montagne s'alimentent principalement de feuillages dans le sous-bois herbacĂ dense prĂsent presque partout dans leur habitat de la rĂgion des volcans Virunga. Leurs activitĂs alimentaires causent des dommages structurels considĂrables Ă cette vĂgĂtation. Les plantes des espĂces qui sont quantitativement les plus importants dans le rĂgime du gorille rĂagissent Ă ces dĂgats en augmentant leur productivitĂ primaire. Aux postes Ăchantillons oĂ les gorilles se sont nourris, ces espĂces prĂsentent des taux de croissance significantivement supĂrieurs sur un intervalle de six mois, par rapport aux postes voisins qui n'ont pas ĂtĂ touchĂs par les gorilles. Les densitĂs de tiges des espĂces herbacĂes appĂtĂes aux postes de nourrissage augmentent nettement aussi bien en comparaison avec leurs valeurs antĂrieures qu'avec celles de ces mÄmes espĂces dans des stations non touchĂes. En consĂquence, les postes oĂ les gorilles se sont nourris ont plus de chance de devenir des futurs postes de nourrissage trĂs attractifs. Il est peu probable que les gorilles âgĂrentâ leur habitat d'une quelconque faĂon, surtout parce qu'ils n'ont pas l'utilisation exclusive de leur domaine vital. Leurs activitĂs semblent maintenir Ă court terme la productivitĂ de leur habitat, sur une Ăchelle de temps comprenant les visites successives de groupes sociaux, et peuvent contribuer Ă long terme Ă des altĂrations bĂnĂfiques pour ces zones rĂguliĂrement frĂquentĂes. Des effets du type rapportĂ ici peuvent avoir ĂtĂ un ĂlĂment important de l'adaptation des gorilles Ă la folivorie terrestre.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75171/1/j.1365-2028.1987.tb01102.x.pd
Neurophysiology
Contains research objectives and reports on one research project.U. S. Air Force Cambridge Research Laboratories under Contract AF19(628)-4147Bell Telephone Laboratories, Inc.National Institutes of Health (Grant MH-04737-04)National Science Foundation (Grant GP-2495)National Institutes of Health (Grant NB-04987-02)The Teagle Foundation, Inc.National Aeronautics and Space Administration (Grant NsG-496)U. S. Air Force (Aeronautical Systems Division) under Contract AF 33(615)-1747National Institutes of Health (Grant NB-04985-01
Transcranial magnetic stimulation in sport science: a commentary
The aim of this commentary is to provide a brief overview of transcranial magnetic stimulation (TMS) and highlight how this technique can be used to investigate the acute and chronic responses of the central nervous system to exercise.
We characterise the neuromuscular responses to TMS and discuss how these measures can be used to investigate the mechanisms of fatigue in response to locomotor exercise. We also discuss how TMS might be used to study the corticospinal adaptations to resistance exercise training, with particular emphasis on the responses to shortening/lengthening contractions and contralateral training. The limited data to date suggest that TMS is a valuable technique for exploring the mechanisms of central fatigue and neural adaptation
Possible mineral contributions to the diet and health of wild chimpanzees in three East African forests
For financial support, the authors acknowledge the Mohamed bin Zayed Species Conservation Fund grant numbers 0925272, 10251055, 11252562, 12254904, the Royal Zoological Society of Scotland, the Leverhulme Trust grant number ECFâ2013â507, and the Boise Fund.We present new data on the ingestion of minerals from termite mound soil by East African chimpanzees (Pan troglodytes schweinfurthii) living in the Budongo Forest Reserve, Uganda, the Gombe National Park and the Mahale Mountains National Park, Tanzania. Termite mound soil is here shown to be a rich source of minerals, containing high concentrations of iron and aluminum. Termite mound soil is not, however, a source of sodium. The concentrations of iron and aluminum are the highest yet found in any of the mineral sources consumed. Levels of manganese and copper, though not so high as for iron and aluminum, are also higher than in other dietary sources. We focus on the contribution of termite mound soil to other known sources of mineral elements consumed by these apes, and compare the mineral content of termite soil with that of control forest soil, decaying wood, clay, and the normal plantâbased chimpanzee diet at Budongo. Samples obtained from Mahale Mountains National Park and Gombe National Park, both in Tanzania, show similar mineral distribution across sources. We suggest three distinct but related mechanisms by which minerals may come to be concentrated in the aboveâmentioned sources, serving as potentially important sources of essential minerals in the chimpanzee diet.PostprintPeer reviewe
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