66 research outputs found
Translating research into policy and practice in developing countries: a case study of magnesium sulphate for pre-eclampsia.
BACKGROUND: The evidence base for improving reproductive health continues to grow. However, concerns remain that the translation of this evidence into appropriate policies is partial and slow. Little is known about the factors affecting the use of evidence by policy makers and clinicians, particularly in developing countries. The objective of this study was to examine the factors that might affect the translation of randomised controlled trial (RCT) findings into policies and practice in developing countries. METHODS: The recent publication of an important RCT on the use of magnesium sulphate to treat pre-eclampsia provided an opportunity to explore how research findings might be translated into policy. A range of research methods, including a survey, group interview and observations with RCT collaborators and a survey of WHO drug information officers, regulatory officials and obstetricians in 12 countries, were undertaken to identify barriers and facilitators to knowledge translation. RESULTS: It proved difficult to obtain reliable data regarding the availability and use of commonly used drugs in many countries. The perceived barriers to implementing RCT findings regarding the use of magnesium sulphate for pre-eclampsia include drug licensing and availability; inadequate and poorly implemented clinical guidelines; and lack of political support for policy change. However, there were significant regional and national differences in the importance of specific barriers. CONCLUSION: The policy changes needed to ensure widespread availability and use of magnesium sulphate are variable and complex. Difficulties in obtaining information on availability and use are combined with the wide range of barriers across settings, including a lack of support from policy makers. This makes it difficult to envisage any single intervention strategy that might be used to promote the uptake of research findings on magnesium sulphate into policy across the study settings. The publication of important trials may therefore not have the impacts on health care that researchers hope for
Spatially resolved detection of crystallized water ice in a TTauri object
We search for frozen water and its processing around young stellar objects
(YSOs of class I/II). We try to detect potential, regional differences in water
ice evolution within YSOs, which is relevant to understanding the chemical
structure of the progenitors of protoplanetary systems and the evolution of
solid materials. Water plays an important role as a reaction bed for rich
chemistry and is an indispensable requirement for life as known on Earth. We
present our analysis of NAOS-CONICA/VLT spectroscopy of water ice at 3um for
the TTauri star YLW 16A in the rho-Ophiuchi molecular cloud. We obtained
spectra for different regions of the circumstellar environment. The observed
absorption profiles are deconvolved with the mass extinction profiles of
amorphous and crystallized ice measured in laboratory. We take into account
both absorption and scattering by ice grains. Water ice in YLW 16A is detected
with optical depths of between tau=1.8 and tau=2.5. The profiles that are
measured can be fitted predominantly by the extinction profiles of small grains
(0.1um - 0.3um) with a small contribution from large grains (<10%). However, an
unambiguous trace of grain growth cannot be found. We detected crystallized
water ice spectra that have their origin in different regions of the
circumstellar environment of the TTauri star YLW 16A. The crystallinity
increases in the upper layers of the circumstellar disk, while only amorphous
grains exist in the bipolar envelope. As in studies of silicate grains in
TTauri objects, the higher crystallinity in the upper layers of the outer disk
regions implies that water ice crystallizes and remains crystallized close to
the disk atmosphere where water ice is shielded against hard irradiation.Comment: 17 pages, 13 figures, 4 tables; accepted by Astronomy and
Astrophysic
Visible photodissociation spectroscopy of PAH cations and derivatives in the PIRENEA experiment
The electronic spectra of gas-phase cationic polycyclic aromatic hydrocarbons
(PAHs), trapped in the Fourier Transform Ion Cyclotron Resonance cell of the
PIRENEA experiment, have been measured by multiphoton dissociation spectroscopy
in the 430-480 nm spectral range using the radiation of a mid-band optical
parametric oscillator laser. We present here the spectra recorded for different
species of increasing size, namely the pyrene cation (C16H10+), the
1-methylpyrene cation (CH3-C16H9+), the coronene cation (C24H12+), and its
dehydrogenated derivative C24H10+. The experimental results are interpreted
with the help of time-dependent density functional theory calculations and
analysed using spectral information on the same species obtained from matrix
isolation spectroscopy data. A kinetic Monte Carlo code has also been used, in
the case of pyrene and coronene cations, to estimate the absorption
cross-sections of the measured electronic transitions. Gas-phase spectra of
highly reactive species such as dehydrogenated PAH cations are reported for the
first time
Some empirical estimates of the H2 formation rate in photon-dominated regions
We combine recent ISO observations of the vibrational ground state lines of
H2 towards Photon-Dominated Regions (PDRs) with observations of vibrationally
excited states made with ground-based telescopes in order to constrain the
formation rate of H2 on grain surfaces under the physical conditions in the
layers responsible for H2 emission. We use steady state PDR models in order to
examine the sensitivity of different H2 line ratios to the H2 formation rate
Rf. We show that the ratio of the 0-0 S(3) to the 1-0 S(1) line increases with
Rf but that one requires independent estimates of the radiation field incident
upon the PDR and the density in order to infer Rf from the H2 line data. We
confirm the earlier result of Habart et al. (2003) that the H2 formation rate
in regions of moderate excitation such as Oph W, S140 and IC 63 is a factor of
5 times larger than the standard rate inferred from UV observations of diffuse
clouds. On the other hand, towards regions of higher radiation field such as
the Orion Bar and NGC 2023, we derive H2 formation rates consistent with the
standard value. We find also a correlation between the H2 1-0 S(1) line and PAH
emission suggesting that Rf scales with the PAH abundance. With the aim of
explaining these results, we consider some empirical models of the H2 formation
process. Here we consider both formation on big (a~0.1 microns) and small (a~10
Angstroms) grains by either direct recombination from the gas phase or
recombination of physisorbed H atoms with atoms in a chemisorbed site. We
conclude that indirect chemisorption is most promising in PDRs. Moreover small
grains which dominate the total grain surface and spend most of their time at
relatively low temperatures may be the most promising surface for forming H2 in
PDRs.Comment: A&A in press, 16 pages, 5 figure
The growth of a culture of evidence-based obstetrics in South Africa: a qualitative case study
<p>Abstract</p> <p>Background</p> <p>While the past two decades have seen a shift towards evidence-based obstetrics and midwifery, the process through which a culture of evidence-based practice develops and is sustained within particular fields of clinical practice has not been well documented, particularly in LMICs (low- and middle-income countries). Forming part of a broader qualitative study of evidence-based policy making, this paper describes the development of a culture of evidence-based practice amongst maternal health policy makers and senior academic obstetricians in South Africa</p> <p>Methods</p> <p>A qualitative case-study approach was used. This included a literature review, a policy document review, a timeline of key events and the collection and analysis of 15 interviews with policy makers and academic clinicians involved in these policy processes and sampled using a purposive approach. The data was analysed thematically.</p> <p>Results</p> <p>The concept of evidence-based medicine became embedded in South African academic obstetrics at a very early stage in relation to the development of the concept internationally. The diffusion of this concept into local academic obstetrics was facilitated by contact and exchange between local academic obstetricians, opinion leaders in international research and structures promoting evidence-based practice. Furthermore the growing acceptance of the concept was stimulated locally through the use of existing professional networks and meetings to share ideas and the contribution of local researchers to building the evidence base for obstetrics both locally and internationally. As a testimony to the extent of the diffusion of evidence-based medicine, South Africa has strongly evidence-based policies for maternal health.</p> <p>Conclusion</p> <p>This case study shows that the combined efforts of local and international researchers can create a culture of evidence-based medicine within one country. It also shows that doing so required time and perseverance from international researchers combined with a readiness by local researchers to receive and actively promote the practice.</p
SUPPORT Tools for evidence-informed health Policymaking (STP) 17: Dealing with insufficient research evidence
This article is part of a series written for people responsible for making decisions about health policies and programmes and for those who support these decision makers
SUPPORT Tools for evidence-informed health Policymaking (STP) 1: What is evidence-informed policymaking?
This article is part of a series written for people responsible for making decisions about health policies and programmes and for those who support these decision makers
Simulating the formation of molecular clouds. I. Slow formation by gravitational collapse from static initial conditions
We study the formation of H2 in the ISM, using a modified version of the
astrophysical magnetohydrodynamical code ZEUS-MP that includes a
non-equilibrium treatment of the formation and destruction of H2. We examine
two different approximations to treat the shielding of H2 against
photodissociation: a local approximation, which gives us a solid lower bound on
the amount of shielding, and a method based on ray-tracing that is considerably
more accurate in some circumstances but that produces results that are harder
to clearly interpret. Either approximation allows one to perform
three-dimensional high-resolution simulations of cloud formation with only
modest computational resources. We also include a detailed treatment of the
thermal behaviour of the gas.
In this paper, we focus on the problem of molecular cloud formation in
gravitationally unstable, initially static gas. We show that in these
conditions, and for initial densities consistent with those observed in the
cold, neutral atomic phase of the interstellar medium, H2 formation occurs on a
timescale t > 10 Myr, comparable to or longer than the gravitational free-fall
timescale of the cloud. We also show that the collapsing gas very quickly
reaches thermal equilibrium and that the equation of state of the gas is
generally softer than isothermal.
Finally, we demonstrate that although these results show little sensitivity
to variations in most of our simulation parameters, they are highly sensitive
to the assumed initial density n_i. Reducing n_i significantly increases the
cloud formation timescale and decreases the amount of hydrogen ultimately
converted to H2. (Abridged).Comment: 89 pages, 40 figures, AASTex. Results section significantly revised
and extended. Includes results from a large number of new simulations
performed using a treatment of H2 photodissociation based on ray-tracing.
This version matches that accepted by ApJ
What are the main inefficiencies in trial conduct : a survey of UKCRC registered clinical trials units in the UK
BACKGROUND: The UK Clinical Research Collaboration (UKCRC) registered Clinical Trials Units (CTUs) Network aims to support high-quality, efficient and sustainable clinical trials research in the UK. To better understand the challenges in efficient trial conduct, and to help prioritise tackling these challenges, we surveyed CTU staff. The aim was to identify important inefficiencies during two key stages of the trial conduct life cycle: (i) from grant award to first participant, (ii) from first participant to reporting of final results. METHODS: Respondents were asked to list their top three inefficiencies from grant award to recruitment of the first participant, and from recruitment of the first participant to publication of results. Free text space allowed respondents to explain why they thought these were important. The survey was constructed using SurveyMonkey and circulated to the 45 registered CTUs in May 2013. Respondents were asked to name their unit and job title, but were otherwise anonymous. Free-text responses were coded into broad categories. RESULTS: There were 43 respondents from 25 CTUs. The top inefficiency between grant award and recruitment of first participant was reported as obtaining research and development (R&D) approvals by 23 respondents (53%), contracts by 22 (51%), and other approvals by 13 (30%). The top inefficiency from recruitment of first participant to publication of results was failure to meet recruitment targets, reported by 19 (44%) respondents. A common comment was that this reflected overoptimistic or inaccurate estimates of recruitment at site. Data management, including case report form design and delays in resolving data queries with sites, was reported as an important inefficiency by 11 (26%) respondents, and preparation and submission for publication by 9 (21%). CONCLUSIONS: Recommendations for improving the efficiency of trial conduct within the CTUs network include: further reducing unnecessary bureaucracy in approvals and contracting; improving training for site staff; realistic recruitment targets and appropriate feasibility; developing training across the network; improving the working relationships between chief investigators and units; encouraging funders to release sufficient funding to allow prompt recruitment of trial staff; and encouraging more research into how to improve the efficiency and quality of trial conduct
Mid-infrared vibrational study of deuterium-containing PAH variants
Polycyclic Aromatic Hydrocarbon (PAH) molecules have been long proposed to be a major carrier of ‘Unidentified Infrared’ (UIR) emission bands that have been observed ubiquitously in various astrophysical environments. These molecules can potentially be an efficient reservoir of deuterium. Once the infrared properties of the deuteriumcontaining PAHs are well understood both experimentally and theoretically, the interstellar UIR bands can be used as a valuable tool to infer the cause of the deuterium depletion in the ISM.
Density Functional Theory (DFT) calculations have been carried out on deuteriumcontaining ovalene variants to study the infrared properties of these molecules. These include deuterated ovalene, cationic deuterated ovalene, deuteronated ovalene and deuterated-deuteronated ovalene. We present a D/H ratio calculated from our theoretical study to compare with the observationally proposed D/H ratio
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