686 research outputs found
An improved method for surface immobilisation of RNA: application to small Non-Coding RNA - mRNA pairing
Characterisation of RNA and its intermolecular interactions is increasing in importance as the inventory of known RNA functions continues to expand. RNA-RNA interactions are central to post-transcriptional gene regulation mechanisms in bacteria, and the interactions of bacterial small non-coding RNAs (sRNAs) with their mRNA targets are the subject of much current research. The technology of surface plasmon resonance (SPR) is an attractive approach to studying these interactions since it is highly sensitive, and allows interaction measurements to be recorded in real-time. Whilst a number of approaches exist to label RNAs for surface-immobilisation, the method documented here is simple, quick, efficient, and utilises the high-affinity streptavidin-biotin interaction. Specifically, we ligate a biotinylated nucleotide to the 3' end of RNA using T4 RNA ligase. Although this is a previously recognised approach, we have optimised the method by our discovery that the incorporation of four or more adenine nucleotides at the 3' end of the RNA (a poly-A-tail) is required in order to achieve high ligation efficiencies. We use this method within the context of investigating small non-coding RNA (sRNA)-mRNA interactions through the application of surface technologies, including quantitative SPR assays. We first focus on validating the method using the recently characterised Escherichia coli sRNA-mRNA pair, MicA-ompA, specifically demonstrating that the addition of the poly-A-tail to either RNA does not affect its subsequent binding interactions with partner molecules. We then apply this method to investigate the novel interactions of a Vibrio cholerae Qrr sRNA with partner mRNAs, hapR and vca0939; RNA-RNA pairings that are important in mediating pathogenic virulence. The calculated binding parameters allow insights to be drawn regarding sRNA-mRNA interaction mechanisms
On the edge of a new frontier: Is gerontological social work in the UK ready to meet twenty-first-century challenges?
This article is available open access through the publisher’s website. Copyright @ 2013 The Authors.This article explores the readiness of gerontological social work in the UK for meeting the challenges of an ageing society by investigating the focus on work with older people in social work education and the scope of gerontological social work research. The discussion draws on findings from two exploratory studies: a survey of qualifying master's programmes in England and a survey of the content relating to older people over a six-year period in four leading UK social work journals. The evidence from master's programmes suggests widespread neglect of ageing in teaching content and practice learning. Social work journals present a more nuanced picture. Older people emerge within coverage of generic policy issues for adults, such as personalisation and safeguarding, and there is good evidence of the complexity of need in late life. However, there is little attention to effective social work interventions, with an increasingly diverse older population, or to the quality of gerontological social work education. The case is made for infusing content on older people throughout the social work curriculum, for extending practice learning opportunities in social work with older people and for increasing the volume and reporting of gerontological social work research.Brunel Institute for Ageing Studie
High Metal Enrichments in Luminous Quasars
We discuss observations of the broad emission line in luminous intermediate redshift quasars, with emphasis on Q0207 -398. This object has relatively sharp lines, allowing us to deconvolve the profiles into distinct components. In this paper we examine the high ionization region, which we show must be matter-bounded, partially transparent to ionizing radiation. We measure a large N V λ1240/He II λ1640 ratio in Q0207-398, but detailed calculations predict this ratio to be ~1 for standard cloud properties. We show that no choice of incident continuum, ionizing photon flux, density, or even the appeal to nonradiative energy sources, can reproduce the observed N V, C IV, O VI, He II spectrum with solar abundances. The intensity of the N V line is sensitive to the abundance of the gas because the abundance of nitrogen, a secondary element goes up roughly as the square of the metallicity. The lowest metallicity capable of reproducing the N V spectrum in Q0207 - 398 is Z ~ 5 Z☉, consistent with that inferred to exist in the cores of massive galaxies after epochs of rapid star formation.
Our final model of the high-ionization emission region is one with many properties similar to those inferred for broad absorption-line QSO absorption-line clouds
High-density functional-RNA arrays as a versatile platform for studying RNA-based interactions
We are just beginning to unravel the myriad of interactions in which non-coding RNAs participate. The intricate RNA interactome is the foundation of many biological processes, including bacterial virulence and human disease, and represents unexploited resources for the development of potential therapeutic interventions. However, identifying specific associations of a given RNA from the multitude of possible binding partners within the cell requires robust high-throughput systems for their rapid screening. Here, we present the first demonstration of functional-RNA arrays as a novel platform technology designed for the study of such interactions using immobilized, active RNAs. We have generated high-density RNA arrays by an innovative method involving surface-capture of in vitro transcribed RNAs. This approach has significant advantages over existing technologies, particularly in its versatility in regards to binding partner character. Indeed, proof-of-principle application of RNA arrays to both RNA-small molecule and RNA-RNA pairings is demonstrated, highlighting their potential as a platform technology for mapping RNA-based networks and for pharmaceutical screening. Furthermore, the simplicity of the method supports greater user-accessibility over currently available technologies. We anticipate that functional-RNA arrays will find broad utility in the expanding field of RNA characterization
Lars Hætta’s miniature world: Sámi prison op-art autoethnography
This article examines a collection of miniature objects, now held in museum collections, which were originally made by a Sámi political prisoner in Norway during the mid-19th century as part of an educational programme. The author draws on recent developments in the theory of miniaturization to consider these miniatures as examples of prison op-art autoethnography: communicative devices which seek to address broad and complex social issues through the process of the creation and distribution of semiophorically functionless mimetic objects of reduced scale and complexity, and which reflect the restrictions of incarcerated artistic expression and the questions this raises regarding authenticity and hybridity
Caribbean Spiny Lobster Fishery Is Underpinned by Trophic Subsidies from Chemosynthetic Primary Production
Data files are deposited with Figshare and are available at: https://dx.doi.org/10.6084/ m9.figshare.4225334
ER and HER2 expression are positively correlated in HER2 non-overexpressing breast cancer
PMCID: PMC3446380This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited
Sex Differences in Diabetes Risk and the Effect of Intensive Lifestyle Modification in the Diabetes Prevention Program
OBJECTIVE—In participants of the Diabetes Prevention Program (DPP) randomized to intensive lifestyle modification (ILS), meeting ILS goals strongly correlated with prevention of diabetes in the group as a whole. Men met significantly more ILS goals than women but had a similar incidence of diabetes. Therefore, we explored sex differences in risk factors for diabetes and the effect of ILS on risk factors
On the growth and form of spherulites
Many structural materials (metal alloys, polymers, minerals, etc.) are formed
by quenching liquids into crystalline solids. This highly non-equilibrium
process often leads to polycrystalline growth patterns that are broadly termed
"spherulites" because of their large-scale average spherical shape. Despite the
prevalence and practical importance of spherulite formation, only rather
qualitative concepts of this phenomenon exist. The present work explains the
growth and form of these fundamental condensed matter structures on the basis
of a unified field theoretic approach. Our phase field model is the first to
incorporate the essential ingredients for this type crystal growth:
anisotropies in both the surface energy and interface mobilities that are
responsible for needle-like growth, trapping of local orientational order due
to either static heterogeneities (impurities) or dynamic heterogeneities in
highly supercooled liquids, and a preferred relative grain orientation induced
by a misorientation-dependent grain boundary energy. Our calculations indicate
that the diversity of spherulite growth forms arises from a competition between
the ordering effect of discrete local crystallographic symmetries and the
randomization of the local crystallographic orientation that accompanies
crystal grain nucleation at the growth front (growth front nucleation or GFN).
The large-scale isotropy of spherulitic growth arises from the predominance of
GFN.Comment: 14 pages, 11 figure
Degradation of polyurethanes in vitro and in vitro: comparison of different models
This study compares and contrasts mechanisms of polyetherurethane (PEU) degradation in vitro and in vivo. Models comprising incubation with hydrogen peroxide in vitro (H2O2), in vivo subcutaneous rat implant (SUBQ), and subcutaneous rat cage implant (CAGE) are described and compared with in vivo degradation of the pacemaker lead device retrieved after human implant (PACE). Experimental results support the hypothesis that stress accelerates PEU degradation. Scanning electron microscopy (SEM), gel permeation chromatography (GPC), and Fourier transform IR spectroscopy/attenuated total reflectance (FT-1R/ATR) evaluation of tested PEU samples suggests, for all models, decreased soft segment and increased ester functionality at the polymer surface. These observations are consistent with a single, metal ion catalyzed, polyester intermediate, oxidative degradation mechanism common to all models, and with device performance in vivo. Model comparison suggests that in vitro H2O2 and in vivo SUBQ and CAGE models accurately mimic in vivo degradation of the pacemaker lead device (PACE).Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/30454/1/0000080.pd
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