Photochemistry and photophysics of anthracenes on silica gel

Studies have been carried out investigating the photochemical and photophysical properties of anthracene adsorbed on silica gel. The photochemistry and photo physics of anthracene in solution are well reported and known, hence its choice as a probe for the silica gel surface. UV -visible absorption and fluorescence spectra of anthracene adsorbed on silica gel reveal aggregate formation at very low loadings (1 % of a monolayer) indicating preferential adsorption occurs at some surface sites. Laser flash photolysis at 355 nm produces both the triplet and radical cation of anthracene, their production was found to be mono- and multi-photonic respectively. The decays of both these transients were complex and the rates increased with increasing loading. Analysis of the triplet state decay has been carried out by studying the delayed fluorescence which arises from triplet triplet annihilation. Fractal and twodimensional models have been used to describe this bimolecular decay. The coadsorption of anthracene and an electron donor having an oxidation potential below 1.09 V on silica gel causes electron transfer to occur from the electron donor to the anthracene radical cation produced following laser flash photolysis at 355 nm. Studies using a selection of electron donors with varying reduction potentials were carried out. The electron donor transfers an electron to the anthracene radical cation, thus greatly accelerating its rate of decay; for electron donors such as triphenylamine, N,N-dimethylaniline and N,N,N',N'tetramethyl- l,4-phenylenediamine the rise of the donor radical cation is observed as the anthracene cation decays. These systems were studied using fluorescence measurements and laser flash photolysis to study any fluorescence quenching and the rate of decay of both the anthracene triplet and radical cation. A selection of anthracene derivatives adsorbed onto silica gel were also briefly studied to see the effect of substituent group and its position. Symmetrically substituted dialkoxyanthracenes and 9-cyanoanthracene were used. The transient absorption spectra of the 2,3- and 2,6-dialkoxyderivatives and 9-cyanoanthracene revealed spectral similarities with that of unsubstituted anthracene. The spectra of9,10- and I,S-didecyloxyanthracene showed significant differences in the radical cation spectra to those obtained for unsubstituted anthracene

Evidence-based commissioning in the English NHS : who uses which sources of evidence? A survey 2010/2011

Objectives: To investigate types of evidence used by healthcare commissioners when making decisions and whether decisions were influenced by commissioners’ experience, personal characteristics or role at work. Design: Cross-sectional survey of 345 National Health Service (NHS) staff members. Setting: The study was conducted across 11 English Primary Care Trusts between 2010 and 2011. Participants: A total of 440 staff involved in commissioning decisions and employed at NHS band 7 or above were invited to participate in the study. Of those, 345 (78%) completed all or a part of the survey. Main outcome measures: Participants were asked to rate how important different sources of evidence (empirical or practical) were in a recent decision that had been made. Backwards stepwise logistic regression analyses were undertaken to assess the contributions of age, gender and professional background, as well as the years of experience in NHS commissioning, pay grade and work role. Results: The extent to which empirical evidence was used for commissioning decisions in the NHS varied according to the professional background. Only 50% of respondents stated that clinical guidelines and cost-effectiveness evidence were important for healthcare decisions. Respondents were more likely to report use of empirical evidence if they worked in Public Health in comparison to other departments (p<0.0005, commissioning and contracts OR 0.32, 95%CI 0.18 to 0.57, finance OR 0.19, 95%CI 0.05 to 0.78, other departments OR 0.35, 95%CI 0.17 to 0.71) or if they were female (OR 1.8 95% CI 1.01 to 3.1) rather than male. Respondents were more likely to report use of practical evidence if they were more senior within the organisation (pay grade 8b or higher OR 2.7, 95%CI 1.4 to 5.3, p=0.004 in comparison to lower pay grades). Conclusions: Those trained in Public Health appeared more likely to use external empirical evidence while those at higher pay scales were more likely to use practical evidence when making commissioning decisions. Clearly, National Institute for Clinical Excellence (NICE) guidance and government publications (eg, National Service Frameworks) are important for decision-making, but practical sources of evidence such as local intelligence, benchmarking data and expert advice are also influential

The relationship between MEG and fMRI

In recent years functional neuroimaging techniques such as fMRI, MEG, EEG and PET have provided researchers with a wealth of information on human brain function. However none of these modalities can measure directly either the neuro-electrical or neuro-chemical processes that mediate brain function. This means that metrics directly reflecting brain ‘activity’ must be inferred from other metrics (e.g. magnetic fields (MEG) or haemodynamics (fMRI)). To overcome this limitation, many studies seek to combine multiple complementary modalities and an excellent example of this is the combination of MEG (which has high temporal resolution) with fMRI (which has high spatial resolution). However, the full potential of multi-modal approaches can only be truly realised in cases where the relationship between metrics is known. In this paper, we explore the relationship between measurements made using fMRI and MEG. We describe the origins of the two signals as well as their relationship to electrophysiology. We review multiple studies that have attempted to characterise the spatial relationship between fMRI and MEG, and we also describe studies that exploit the rich information content of MEG to explore differing relationships between MEG and fMRI across neural oscillatory frequency bands. Monitoring the brain at “rest” has become of significant recent interest to the neuroimaging community and we review recent evidence comparing MEG and fMRI metrics of functional connectivity. A brief discussion of the use of magnetic resonance spectroscopy (MRS) to probe the relationship between MEG/fMRI and neurochemistry is also given. Finally, we highlight future areas of interest and offer some recommendations for the parallel use of fMRI and MEG

Controlling kinetic pathways in demixing microgel-micelle mixtures

[Image: see text] We investigate the temperature-dependent phase behavior of mixtures of poly(N-isopropylacrylamide) (pNIPAM) microgel colloids and a triblock copolymer (PEO–PPO–PEO) surfactant. Usually, gelation in these systems results from an increase in temperature. Here we investigate the role of the heating rate, and surprisingly, we find that this causes the mechanism of aggregation to change from one which is driven by depletion of the microgels by the micelles at low temperatures to the association of the two species at high temperatures. We thus reveal two competing mechanisms for attractions between the microgel particles which can be controlled by changing the heating rate. We use this heating-rate-dependent response of the system to access multiple structures for the same system composition. Samples were found to demix into phases rich and poor in microgel particles at temperatures below 33 °C, under conditions where the microgels particles are partially swollen. Under rapid heating full demixing is bypassed, and gel networks are formed instead. The temperature history of the sample, therefore, allows for kinetic selection between different final structures, which may be metastable

The Mayer Hashi Large-Scale Program to Increase Use of Long-Acting Reversible Contraceptives and Permanent Methods in Bangladesh: Explaining the Disappointing Results. An Outcome and Process Evaluation

Background: Bangladesh has achieved a low total fertility rate of 2.3. Two-thirds of currently married women of reproductive age (CMWRA) want to limit fertility, and many women achieve their desired fertility before age 30. The incidence of unintended pregnancy and pregnancy termination is high, however. Long-acting reversible contraceptives (LARCs), consisting of the intrauterine device and implant, and permanent methods (PM), including female sterilization and vasectomy, offer several advantages in this situation, but only 8% of CMWRA or 13% of method users use these methods. Program: The Mayer Hashi (MH) program (2009–2013) aimed to improve access to and the quality of LARC/PM services in 21 of the 64 districts in Bangladesh. It was grounded in the SEED (supply–enabling environment–demand) Programming Model. Supply improvements addressed provider knowledge and skills, system strengthening, and logistics. Creating an enabling environment involved holding workshops with local and community leaders, including religious leaders, to encourage them to help promote demand for LARCs and PMs and overcome cultural barriers. Demand promotion encompassed training of providers in counseling, distribution of behavior change communication materials in the community and in facilities, and community mobilization. Methods: We selected 6 MH program districts and 3 nonprogram districts to evaluate the program. We used a before– after and intervention–comparison design to measure the changes in key contraceptive behavior outcomes, and we used a difference-in-differences (DID) specification with comparison to the nonprogram districts to capture the impact of the program. In addition to the outcome evaluation, we considered intermediate indicators that measured the processes through which the interventions were expected to affect the use of LARCs and PMs. Results: The use of LARCs/PMs among CMWRA increased between 2010 and 2013 in both program (from 5.3% to 7.5%) and nonprogram (from 5.0% to 8.9%) districts, but the rate of change was higher in the nonprogram districts. Client–provider interaction and exposure to LARCs/PMs were lower in the program than nonprogram districts, and the MH program districts had higher vacancies of key providers than the nonprogram areas, both indications of a more difficult health system environment. Conclusion: The weaknesses in the health system in the MH districts apparently undermined the effectiveness of the program. More attention to system weaknesses, such as additional supportive supervision for providers, might have improved the outcome

Long-term effects of the Active for Life Year 5 (AFLY5) school-based cluster randomised controlled trial

Objective: To investigate the long-term effectiveness of a school-based intervention to improve physical activity and diet in children. Design: Cluster-randomised controlled trial. Setting: 60 primary schools in the southwest of England. Participants: Primary school children who were aged 8-9 years at recruitment, 9-10 years during the intervention and 10-11 years at the long-term follow-up assessment. Intervention: Teacher training, provision of lesson and child-parent interactive homework plans and teaching materials. Main Outcome Measures: Primary outcomes were accelerometer-assessed minutes of moderate to vigorous physical activity (MVPA) per day, accelerometer-assessed minutes of sedentary behaviour per day and reported daily consumption of servings of fruit and vegetables. Results: 60 schools with 2221 eligible children were recruited. As in the previously published assessment immediately after the end of the intervention, none of the three primary outcomes differed between children in schools allocated to the intervention, compared with those in control schools at the end of the long-term follow-up (1 year after the end of the intervention). Differences in secondary outcomes were consistent with those at the immediate follow-up, with no evidence that these had diminished over time. Comparing intervention with control schools, the difference in mean child-reported screen viewing at the weekend was -16.03 min (95% CI -32.82 to 0.73), for servings of snacks per day, the difference was -0.11 (95% CI -0.39 to 0.06), in servings of high-energy drinks per day -0.20 (95% CI -0.39 to -0.01) and in servings of high-fat foods per day -0.12 (95% CI -0.39 to 0.00). None of these reached our predefined level of statistical significance, especially after accounting for multiple testing. Conclusions: School-based curriculum interventions alone are unlikely to have a major public health impact on children's diet and physical activity.Emma L Anderson, Laura D Howe, Ruth R Kipping, Rona Campbell, Russell Jago, Sian M Noble, Sian Wells, Catherine Chittleborough, Tim J Peters, Debbie A Lawlo

Using referral rates for genetic testing to determine the incidence of a rare disease: The minimal incidence of congenital hyperinsulinism in the UK is 1 in 28,389

ongenital hyperinsulinism (CHI) is a significant cause of hypoglycaemia in neonates and infants with the potential for permanent neurologic injury. Accurate calculations of the incidence of rare diseases such as CHI are important as they inform health care planning and can aid interpretation of genetic testing results when assessing the frequency of variants in large-scale, unselected sequencing databases. Whilst minimal incidence rates have been calculated for four European countries, the incidence of CHI in the UK is not known. In this study we have used referral rates to a central laboratory for genetic testing and annual birth rates from census data to calculate the minimal incidence of CHI within the UK from 2007 to 2016. CHI was diagnosed in 278 individuals based on inappropriately detectable insulin and/or C-peptide measurements at the time of hypoglycaemia which persisted beyond 6 months of age. From these data, we have calculated a minimum incidence of 1 in 28,389 live births for CHI in the UK. This is comparable to estimates from other outbred populations and provides an accurate estimate that will aid both health care provision and interpretation of genetic results, which will help advance our understanding of CHI.This article is freely available via Open Access. Click on the publisher URL to access it via the publisher's site.SEF has a Sir Henry Dale Fellowship jointly funded by the Wellcome Trust (https://wellcome.ac.uk/funding) and the Royal Society (https://royalsociety.org/grants-schemes-awards/grants/) (Grant Number: 105636/Z/14/Z). The funders did not play any role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.published version, accepted versio

A cohort study of low birth weight and health outcomes in the first year of life, Ghana.

OBJECTIVE: To investigate the effect of birth weight on infant mortality, illness and care seeking in rural Ghana. METHODS: Using randomized controlled trial data, we compared infants weighing 2.00-2.49, 1.50-1.99 and < 1.50 kg with non-low-birth-weight infants. We generated adjusted mortality hazard ratios (aHR), adjusted illness rate ratios (aRR) and adjusted odds ratios (aOR) for health-facility admissions and absence of care seeking for four time periods: infancy, the neonatal period, early infancy and late infancy - represented by ages of 0-364, 0-27, 28-182 and 183-364 days, respectively. FINDINGS: Among 22 906 infants, compared with non-low-birth-weight infants: (i) infants weighing 2.00-2.49, 1.50-1.99 and < 1.50 kg were about two (aHR: 2.13; 95% confidence interval, CI: 1.76-2.59), eight (aHR: 8.21; 95% CI: 6.26-10.76) and 25 (aHR: 25.38; 95% CI: 18.36-35.10) times more likely to die in infancy, respectively; (ii) those born weighing < 1.50 kg were about 48 (aHR: 48.45; 95% CI: 32.81-71.55) and eight (aHR: 8.42; 95% CI: 3.09-22.92) times more likely to die in the neonatal period and late infancy, respectively; (iii) those born weighing 1.50-1.99 kg (aRR: 1.57; 95% CI: 1.27-1.95) or < 1.50 kg (aRR: 1.58; 95% CI: 1.13-2.21) had higher neonatal illness rates; and (iv) for those born weighing 1.50-1.99 kg, care was less likely to be sought in the neonatal period (aOR: 3.30; 95% CI: 1.98-5.48) and early infancy (aOR : 1.74; 95% CI: 1.26-2.39). CONCLUSION: For low-birth-weight infants in Ghana, strategies to minimize mortality and improve care seeking are needed