1,753 research outputs found
Simulationâbased otorhinolaryngology emergencies boot camp: Part 1: Curriculum design and airway skills
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/107579/1/lary24572.pd
Simulationâbased otorhinolaryngology emergencies boot camp: Part 2: Special skills using task trainers
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/107500/1/lary24571.pd
Investigating the Near-Infrared Properties of Planetary Nebulae. I. Narrowband Images
We present the results of a near-infrared narrowband imaging survey of
planetary nebulae. Objects were selected in a way that complements similar
surveys done at visible and near-infrared wavelengths. No new detections of
molecular hydrogen emission were made. The H2 is frequently found to be
extended, except in young, visibly compact objects. Our results are consistent
with the already determined correlation of H2 emission with planetary nebula
morphological type. Filamentary and other kinds of structures are clearly
resolved in many nebulae.Comment: 21 pages text+tables and 38 figures, full preprint available at
http://www.cv.nrao.edu/html/library/nrao_preprints.html, report #9571 (4.4MB
gzipped file), or email [email protected]. Accepted ApJS, scheduled
Sept. 199
Chow's theorem and universal holonomic quantum computation
A theorem from control theory relating the Lie algebra generated by vector
fields on a manifold to the controllability of the dynamical system is shown to
apply to Holonomic Quantum Computation. Conditions for deriving the holonomy
algebra are presented by taking covariant derivatives of the curvature
associated to a non-Abelian gauge connection. When applied to the Optical
Holonomic Computer, these conditions determine that the holonomy group of the
two-qubit interaction model contains . In particular, a
universal two-qubit logic gate is attainable for this model.Comment: 13 page
Developing fencing policies in dryland ecosystems
The daily energy requirements of animals are determined by a combination of physical and physiological factors, but food availability may challenge the capacity to meet nutritional needs. Western gorillas (Gorilla gorilla) are an interesting model for investigating this topic because they are folivore-frugivores that adjust their diet and activities to seasonal variation in fruit availability. Observations of one habituated group of western gorillas in Bai-Hokou, Central African Republic (December 2004-December 2005) were used to examine seasonal variation in diet quality and nutritional intake. We tested if during the high fruit season the food consumed by western gorillas was higher in quality (higher in energy, sugar, fat but lower in fibre and antifeedants) than during the low fruit season. Food consumed during the high fruit season was higher in digestible energy, but not any other macronutrients. Second, we investigated whether the gorillas increased their daily intake of carbohydrates, metabolizable energy (KCal/g OM), or other nutrients during the high fruit season. Intake of dry matter, fibers, fat, protein and the majority of minerals and phenols decreased with increased frugivory and there was some indication of seasonal variation in intake of energy (KCal/g OM), tannins, protein/fiber ratio, and iron. Intake of non-structural carbohydrates and sugars was not influenced by fruit availability. Gorillas are probably able to extract large quantities of energy via fermentation since they rely on proteinaceous leaves during the low fruit season. Macronutrients and micronutrients, but not digestible energy, may be limited for them during times of low fruit availability because they are hind-gut fermenters. We discuss the advantages of seasonal frugivores having large dietary breath and flexibility, significant characteristics to consider in the conservation strategies of endangered species
Methane yield phenotypes linked to differential gene expression in the sheep rumen microbiome.
Ruminant livestock represent the single largest anthropogenic source of the potent greenhouse gas methane, which is generated by methanogenic archaea residing in ruminant digestive tracts. While differences between individual animals of the same breed in the amount of methane produced have been observed, the basis for this variation remains to be elucidated. To explore the mechanistic basis of this methane production, we measured methane yields from 22 sheep, which revealed that methane yields are a reproducible, quantitative trait. Deep metagenomic and metatranscriptomic sequencing demonstrated a similar abundance of methanogens and methanogenesis pathway genes in high and low methane emitters. However, transcription of methanogenesis pathway genes was substantially increased in sheep with high methane yields. These results identify a discrete set of rumen methanogens whose methanogenesis pathway transcription profiles correlate with methane yields and provide new targets for CH4 mitigation at the levels of microbiota composition and transcriptional regulation
Lung Regeneration: Endogenous and Exogenous Stem Cell Mediated Therapeutic Approaches
The tissue turnover of unperturbed adult lung is remarkably slow. However, after injury or
insult, a specialised group of facultative lung progenitors become activated to replenish damaged
tissue through a reparative process called regeneration. Disruption in this process results in healing by
fibrosis causing aberrant lung remodelling and organ dysfunction. Post-insult failure of regeneration
leads to various incurable lung diseases including chronic obstructive pulmonary disease (COPD) and
idiopathic pulmonary fibrosis. Therefore, identification of true endogenous lung progenitors/stem
cells, and their regenerative pathway are crucial for next-generation therapeutic development. Recent
studies provide exciting and novel insights into postnatal lung development and post-injury lung
regeneration by native lung progenitors. Furthermore, exogenous application of bone marrow stem
cells, embryonic stem cells and inducible pluripotent stem cells (iPSC) show evidences of their
regenerative capacity in the repair of injured and diseased lungs. With the advent of modern tissue
engineering techniques, whole lung regeneration in the lab using de-cellularised tissue scaffold
and stem cells is now becoming reality. In this review, we will highlight the advancement of our
understanding in lung regeneration and development of stem cell mediated therapeutic strategies in
combating incurable lung diseases
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Evaluating forecasts of extreme events for hydrological applications: an approach for screening unfamiliar performance measures
Many different performance measures have been developed to evaluate field predictions in meteorology. However, a researcher or practitioner encountering a new or unfamiliar measure may have difficulty in interpreting its results, which may lead to them avoiding new measures and relying on those that are familiar. In the context of evaluating forecasts of extreme events for hydrological applications, this article aims to promote the use of a range of performance measures. Some of the types of performance measures that are introduced in order to demonstrate a six-step approach to tackle a new measure. Using the example of the European Centre for Medium-Range Weather Forecasts (ECMWF) ensemble precipitation predictions for the Danube floods of July and August 2002, to show how to use new performance measures with this approach and the way to choose between different performance measures based on their suitability for the task at hand is shown. Copyright © 2008 Royal Meteorological Societ
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