363 research outputs found
Minimum accommodation for aerobrake assembly, phase 2
A multi-element study was done to assess the practicality of a Space Station Freedom-based aerobrake system for the Space Exploration Initiative. The study was organized into six parts related to structure, aerodynamics, robotics and assembly, thermal protection system, inspection, and verification, all tied together by an integration study. The integration activity managed the broad issues related to meeting mission requirements. This report is a summary of the issues addressed by the integration team
Using knowledge brokers to facilitate the uptake of pediatric measurement tools into clinical practice: a before-after intervention study
<p>Abstract</p> <p>Background</p> <p>The use of measurement tools is an essential part of good evidence-based practice; however, physiotherapists (PTs) are not always confident when selecting, administering, and interpreting these tools. The purpose of this study was to evaluate the impact of a multifaceted knowledge translation intervention, using PTs as knowledge brokers (KBs) to facilitate the use in clinical practice of four evidence-based measurement tools designed to evaluate and understand motor function in children with cerebral palsy (CP). The KB model evaluated in this study was designed to overcome many of the barriers to research transfer identified in the literature.</p> <p>Methods</p> <p>A mixed methods before-after study design was used to evaluate the impact of a six-month KB intervention by 25 KBs on 122 practicing PTs' self-reported knowledge and use of the measurement tools in 28 children's rehabilitation organizations in two regions of Canada. The model was that of PT KBs situated in clinical sites supported by a network of KBs and the research team through a broker to the KBs. Modest financial remuneration to the organizations for the KB time (two hours/week for six months), ongoing resource materials, and personal and intranet support was provided to the KBs. Survey data were collected by questionnaire prior to, immediately following the intervention (six months), and at 12 and 18 months. A mixed effects multinomial logistic regression was used to examine the impact of the intervention over time and by region. The impact of organizational factors was also explored.</p> <p>Results</p> <p>PTs' self-reported knowledge of all four measurement tools increased significantly over the six-month intervention, and reported use of three of the four measurement tools also increased. Changes were sustained 12 months later. Organizational culture for research and supervisor expectations were significantly associated with uptake of only one of the four measurement tools.</p> <p>Conclusions</p> <p>KBs positively influenced PTs' self-reported knowledge and self-reported use of the targeted measurement tools. Further research is warranted to investigate whether this is a feasible, cost-effective model that could be used more broadly in a rehabilitation setting to facilitate the uptake of other measurement tools or evidence-based intervention approaches.</p
Comblike, Monodisperse Polypeptoid Drag-Tags for DNA Separations by End-Labeled Free-Solution Electrophoresis (ELFSE)
The development of innovative technologies designed to reduce the cost and increase the throughput of DNA separations continues to be important for large-scale sequencing and genotyping efforts. We report research aimed at the further development of a free-solution bioconjugate method of DNA size separation by capillary electrophoresis (CE), in particular, the determination of an optimal molecular architecture for polyamide-based "drag-tags". We synthesized several branched poly(N-methoxyethyl glycine)s (poly(NMEG)s, a class of polypeptoids) as novel friction-generating entities for end-on attachment to DNA molecules. A 30-mer poly(NMEG) "backbone," comprising five evenly spaced reactive -amino groups, was synthesized on solid phase, cleaved, and purified to monodispersity by RP-HPLC. Three different comblike derivatives of this backbone molecule were created by (1) acetylating the -amino groups or (2) appending small, monodisperse NMEG oligomers (a tetramer and an octamer). Grafting of the oligo(NMEG)s was done using solution-phase amide bond formation chemistry. Once purified to total monodispersity, the three different drag-tags were studied by freesolution electrophoresis to observe the effect of branching on their hydrodynamic drag or "R" and hence their ability to separate DNA. Drag was found to scale linearly with total molecular weight, regardless of branch length. The octamer-branched drag-tag-DNA conjugate was used to separate ssDNA products of 50, 75, 100, and 150 bases in length by free-solution CE in less than 10 min. Hence, the use of branched or comblike drag-tags is both a feasible and an effective way to achieve high frictional drag, allowing the high-resolution separation of relatively large DNA molecules by free-solution CE without the need to synthesize very long polymers
Social democracy, embeddedness and decommodification: On the conceptual innovations and intellectual affiliations of Karl Polanyi
Of the several debates that revolve around the work of the economic historian and political economist Karl Polanyi, one that continues to exercise minds concerns his analysis of, and political attitudes toward, post-war capitalism and the welfare state. Simplified a little, it is a debate with two sides. To borrow IvĂĄn SzelĂ©nyi's terms, one side constructs a âhardâ Karl Polanyi, the other a âsoftâ one. The former advocated a socialist mixed economy dominated by redistributive mechanisms. He was a radical socialist for whom the market should never be the dominant mechanism of economic coordination. His âsoftâ alter ego insisted that the market system remain essentially intact but be complemented by redistributive mechanisms. The âdouble movementâ â the central thesis of his âGreat Transformationâ â acts, in this reading, as a self-correcting mechanism that moderates the excesses of market fundamentalism; its author was positioned within the social-democratic mainstream for which the only realistic desirable goal is a regulated form of capitalism. In terms of textual evidence there is much to be said for both interpretations. In this article I suggest a different approach, one that focuses upon the meaning of Polanyi's concepts in relation to their socio-political and intellectual environment
The Ks-band Tully-Fisher Relation - A Determination of the Hubble Parameter from 218 ScI Galaxies and 16 Galaxy Clusters
The value of the Hubble Parameter (H0) is determined using the
morphologically type dependent Ks-band Tully-Fisher Relation (K-TFR). The slope
and zero point are determined using 36 calibrator galaxies with ScI morphology.
Calibration distances are adopted from direct Cepheid distances, and group or
companion distances derived with the Surface Brightness Fluctuation Method or
Type Ia Supernova. Distances are determined to 16 galaxy clusters and 218 ScI
galaxies with minimum distances of 40.0 Mpc. From the 16 galaxy clusters a
weighted mean Hubble Parameter of H0=84.2 +/-6 km s-1 Mpc-1 is found. From the
218 ScI galaxies a Hubble Parameter of H0=83.4 +/-8 km s-1 Mpc-1 is found. When
the zero point of the K-TFR is corrected to account for recent results that
find a Large Magellanic Cloud distance modulus of 18.39 +/-0.05 a Hubble
Parameter of 88.0 +/-6 km s-1 Mpc-1 is found. A comparison with the results of
the Hubble Key Project (Freedman et al 2001) is made and discrepancies between
the K-TFR distances and the HKP I-TFR distances are discussed. Implications for
Lamda-CDM cosmology are considered with H0=84 km s-1 Mpc-1. (Abridged)Comment: 37 pages including 12 tables and 7 figures. Final version accepted
for publication in the Journal of Astrophysics & Astronom
The stellar content of the Hamburg/ESO survey. V. The metallicity distribution function of the Galactic halo
We determine the metallicity distribution function (MDF) of the Galactic halo
by means of a sample of 1638 metal-poor stars selected from the Hamburg/ESO
objective-prism survey (HES). The sample was corrected for minor biases
introduced by the strategy for spectroscopic follow-up observations of the
metal-poor candidates, namely "best and brightest stars first". [...] We
determined the selection function of the HES, which must be taken into account
for a proper comparison between the HES MDF with MDFs of other stellar
populations or those predicted by models of Galactic chemical evolution. The
latter show a reasonable agreement with the overall shape of the HES MDF for
[Fe/H] > -3.6, but only a model of Salvadori et al. (2007) with a critical
metallicity for low-mass star formation of Z_cr = 10^{-3.4} * Z_Sun reproduces
the sharp drop at [Fe/H] ~-3.6 present in the HES MDF. [...] A comparison of
the MDF of Galactic globular clusters and of dSph satellites to the Galaxy
shows qualitative agreement with the halo MDF, derived from the HES, once the
selection function of the latter is included. However, statistical tests show
that the differences between these are still highly significant. [ABSTRACT
ABRIDGED]Comment: Accepted for publication in A&
The AMIGA project. I. Optical characterization of the CIG catalog
The AMIGA project (Analysis of the Interstellar Medium of Isolated Galaxies)
is compiling a multiwavelength database of isolated galaxies that includes
optical (B and Halpha), infrared (FIR and NIR) and radio (continuum plus HI and
CO lines) properties. It involves a refinement of the pioneering Catalog of
Isolated Galaxies. This paper is the first in a series and begins with analysis
of the global properties of the nearly redshift-complete CIG with emphasis on
the Optical Luminosity Function (OLF) which we compare with other recent
estimates of the OLF for a variety of environments. The CIG redshift
distribution for n= 956 galaxies re-enforces the evidence for a bimodal
structure seen earlier in smaller samples. The peaks at redshift near 1500 and
6000km/s correspond respectively to galaxies in the local supercluster and
those in more distant large-scale components (particularly Perseus-Pisces). The
two peaks in the redshift distribution are superimposed on 50% or more of the
sample that is distributed in a much more homogeneous way. The CIG probably
represents the most homogeneous local field example that has ever been
compiled. Our derivation of the CIG OLF is consistent with other studies of the
OLF for lower density environments. This comparison via the Schechter parameter
formalization shows that: 1) M* increases with galaxy surface density on the
sky and 2) alpha shows a weaker tendency to do the same. The CIG represents the
largest and most complete foundation for studies of isolated galaxies and is
likely as close as we can come to a field sample. (Tables 1, 2 and 3 are
available in electronic form at http://www.iaa.es/AMIGA.html).Comment: In press in A&
Effects of an evidence service on health-system policy makers' use of research evidence: A protocol for a randomised controlled trial
<p>Abstract</p> <p>Background</p> <p>Health-system policy makers need timely access to synthesised research evidence to inform the policy-making process. No efforts to address this need have been evaluated using an experimental quantitative design. We developed an evidence service that draws inputs from Health Systems Evidence, which is a database of policy-relevant systematic reviews. The reviews have been (a) categorised by topic and type of review; (b) coded by the last year searches for studies were conducted and by the countries in which included studies were conducted; (c) rated for quality; and (d) linked to available user-friendly summaries, scientific abstracts, and full-text reports. Our goal is to evaluate whether a "full-serve" evidence service increases the use of synthesized research evidence by policy analysts and advisors in the Ontario Ministry of Health and Long-Term Care (MOHLTC) as compared to a "self-serve" evidence service.</p> <p>Methods/design</p> <p>We will conduct a two-arm randomized controlled trial (RCT), along with a follow-up qualitative process study in order to explore the findings in greater depth. For the RCT, all policy analysts and policy advisors (n = 168) in a single division of the MOHLTC will be invited to participate. Using a stratified randomized design, participants will be randomized to receive either the "full-serve" evidence service (database access, monthly e-mail alerts, and full-text article availability) or the "self-serve" evidence service (database access only). The trial duration will be ten months (two-month baseline period, six-month intervention period, and two month cross-over period). The primary outcome will be the mean number of site visits/month/user between baseline and the end of the intervention period. The secondary outcome will be participants' intention to use research evidence. For the qualitative study, 15 participants from each trial arm (n = 30) will be purposively sampled. One-on-one semi-structured interviews will be conducted by telephone on their views about and their experiences with the evidence service they received, how helpful it was in their work, why it was helpful (or not helpful), what aspects were most and least helpful and why, and recommendations for next steps.</p> <p>Discussion</p> <p>To our knowledge, this will be the first RCT to evaluate the effects of an evidence service specifically designed to support health-system policy makers in finding and using research evidence.</p> <p>Trial registration</p> <p>ClinicalTrials.gov: <a href="http://www.clinicaltrials.gov/ct2/show/NCT01307228">NCT01307228</a></p
Policymakers\u27 experience of a capacity-building intervention designed to increase their use of research: A realist process evaluation
Background: An interventionâs success depends on how participants interact with it in local settings. Process evaluation examines these interactions, indicating why an intervention was or was not effective, and how it (and similar interventions) can be improved for better contextual fit. This is particularly important for innovative trials like Supporting Policy In health with Research: an Intervention Trial (SPIRIT), where causal mechanisms are poorly understood. SPIRIT was testing a multi-component intervention designed to increase the capacity of health policymakers to use research.
Methods: Our mixed-methods process evaluation sought to explain variation in observed process effects across the six agencies that participated in SPIRIT. Data collection included observations of intervention workshops (n = 59), purposively sampled interviews (n = 76) and participant feedback forms (n = 553). Using a realist approach, data was coded for context-mechanism-process effect configurations (retroductive analysis) by two authors.
Results: Intervention workshops were very well received. There was greater variation of views regarding other aspects of SPIRIT such as data collection, communication and the interventionâs overall value. We identified nine inter-related mechanisms that were crucial for engaging participants in these policy settings: (1) Accepting the premise (agreeing with the studyâs assumptions); (2) Self-determination (participative choice); (3) The Value
Proposition (seeing potential gain); (4) âGetting good stuffâ (identifying useful ideas, resources or connections); (5) Self-efficacy (believing âwe can do this!â); (6) Respect (feeling that SPIRIT understands and values oneâs work); (7) Confidence (believing in the studyâs integrity and validity); (8) Persuasive leadership (authentic and compelling advocacy from leaders); and (9) Strategic insider facilitation (local translation and mediation). These findings were used to develop tentative explanatory propositions and to revise the programme theory.
Conclusion: This paper describes how SPIRIT functioned in six policy agencies, including why strategies that worked well in one site were less effective in others. Findings indicate a complex interaction between participantsâ perception of the intervention, shifting contextual factors, and the form that the intervention took in each site. Our propositions provide transferable lessons about contextualised areas of strength and weakness that may be useful in the development and implementation of similar studies
Targeted Amplicon Sequencing (TAS): A Scalable Next-Gen Approach to Multilocus, Multitaxa Phylogenetics
Next-gen sequencing technologies have revolutionized data collection in genetic studies and advanced genome biology to novel frontiers. However, to date, next-gen technologies have been used principally for whole genome sequencing and transcriptome sequencing. Yet many questions in population genetics and systematics rely on sequencing specific genes of known function or diversity levels. Here, we describe a targeted amplicon sequencing (TAS) approach capitalizing on next-gen capacity to sequence large numbers of targeted gene regions from a large number of samples. Our TAS approach is easily scalable, simple in execution, neither time-nor labor-intensive, relatively inexpensive, and can be applied to a broad diversity of organisms and/or genes. Our TAS approach includes a bioinformatic application, BarcodeCrucher, to take raw next-gen sequence reads and perform quality control checks and convert the data into FASTA format organized by gene and sample, ready for phylogenetic analyses. We demonstrate our approach by sequencing targeted genes of known phylogenetic utility to estimate a phylogeny for the Pancrustacea. We generated data from 44 taxa using 68 different 10-bp multiplexing identifiers. The overall quality of data produced was robust and was informative for phylogeny estimation. The potential for this method to produce copious amounts of data from a single 454 plate (e.g., 325 taxa for 24 loci) significantly reduces sequencing expenses incurred from traditional Sanger sequencing. We further discuss the advantages and disadvantages of this method, while offering suggestions to enhance the approach
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