Understanding/unravelling carotenoid excited singlet states.

Carotenoids are essential light-harvesting pigments in natural photosynthesis. They absorb in the blue–green region of the solar spectrum and transfer the absorbed energy to (bacterio-)chlorophylls, and thus expand the wavelength range of light that is able to drive photosynthesis. This process is an example of singlet–singlet excitation energy transfer, and carotenoids serve to enhance the overall efficiency of photosynthetic light reactions. The photochemistry and photophysics of carotenoids have often been interpreted by referring to those of simple polyene molecules that do not possess any functional groups. However, this may not always be wise because carotenoids usually have a number of functional groups that induce the variety of photochemical behaviours in them. These differences can also make the interpretation of the singlet excited states of carotenoids very complicated. In this article, we review the properties of the singlet excited states of carotenoids with the aim of producing as coherent a picture as possible of what is currently known and what needs to be learned

Ten-year alcohol consumption typologies and trajectories of C-reactive protein, interleukin-6 and interleukin-1 receptor antagonist over the following 12 years: a prospective cohort study.

BACKGROUND: Moderate alcohol consumption is thought to confer cardiometabolic protective effects. Inflammatory pathways are hypothesized to partly underlie this association. OBJECTIVES: The aim of this study was to examine the association between typologies of alcohol consumption and markers of inflammation, and their rate of change over time. METHODS: Data were collected from 8209 participants [69% men; mean age, 50 years (SD 6.1)] of the British Whitehall II study. Alcohol consumption typologies were defined using up to three measures during an approximately 10-year period spanning from 1985 to 1994 as (i) stable nondrinkers, (ii) stable moderate drinkers (referent), (iii) stable heavy drinkers, (iv) nonstable drinkers and (v) former drinkers. C-reactive protein (CRP), interleukin (IL)-6 and IL-1 receptor antagonist (IL-1 RA) were measured up to three times in the following 12 years. RESULTS: Stable moderate drinkers had lower levels of CRP than stable nondrinkers, stable heavy drinkers, former drinkers and nonstable drinkers, but there were no differences in the rate of change in CRP over time between groups. Stable nondrinkers had higher levels of IL-6 as did stable heavy drinkers; rates of change in IL-6 over time were also increased in the latter group. Stable nondrinkers also had higher levels of IL-1 RA. These associations were robust to adjustment for confounding factors. CONCLUSION: Our novel investigation of 10-year drinking typologies shows that stable moderate alcohol consumption is associated with a long-term inflammatory marker profile that is consistent with conferring a reduced risk of developing coronary heart disease.This work was supported by grants from the European Research Council (ERC-StG-2012- 309337_AlcoholLifecourse, PI: Annie Britton, http://www.ucl.ac.uk/alcohol-lifecourse) and UK Medical Research Council/Alcohol Research UK (MR/M006638/1). The Whitehall II study was supported by grants from the UK Medical Research Council (K013351), British Heart Foundation (RG/ 07/008/23674), Stroke Association, National Heart Lung and Blood Institute (HL036310) and National Institute on Aging (AG13196, AG034454).This is the final version of the article. It first appeared from Wiley via http://dx.doi.org/10.1111/joim.1254

Repeatability And Validity Of IUATLD Respiratory Questionnaire Responses As A Measure Of Asthma In An Ethiopian Population

EAMJ Dec. Repeatability.indd Objective: To assess the repeatability and validity of the IUATLD respiratory symptoms questionnaire in relation to exercise-induced bronchoconstriction or bronchodilator responses in a community in southern Ethiopia.Design: A case-control study.Setting: Rural and small town setting in southern Ethiopia, April to May 2006.Subjects: Two hundred and forty seven adults and children who previously reported wheeze in the past year, and 174 who did not.Interventions: Administered IUATLD bronchial symptoms questionnaire; standardised free-running exercise test or (for those with airflow obstruction) assessment of bronchodilator response to inhaled salbutamol.Results: Kappa values for four-week repeatability for the wheeze and asthma questions were 0.61 (95% CI 0.52 to 0.70) and 0.75 (0.63 to 0.87), respectively. Of the 58 people who reported wheeze in 2003 and in April 2006, only five had a positive exercise test or bronchodilator challenge (Positive Predictive Value (PPV) 0.09, 95% CI 0.01 to 0.22). Of the 12 who reported asthma in 2003 and April 2006, three had a positive result to either to exercise test or bronchodilator challenge test (PPV 0.25, 95% CI 0.05 to 0.50).Conclusion: Our findings suggest that self-reported wheeze and asthma have good short-term repeatability, but do not closely reflect exercise-induced bronchospasm or bronchodilator responsiveness. The validity of questionnaire methods of studying asthma epidemiology in developing countries needs further investigation

Structured Variability in Purkinje Cell Activity during Locomotion

The cerebellum is a prominent vertebrate brain structure that is critically involved in sensorimotor function. During locomotion, cerebellar Purkinje cells are rhythmically active, shaping descending signals and coordinating commands from higher brain areas with the step cycle. However, the variation in this activity across steps has not been studied, and its statistical structure, afferent mechanisms, and relationship to behavior remain unknown. Here, using multi-electrode recordings in freely moving rats, we show that behavioral variables systematically influence the shape of the step-locked firing rate. This effect depends strongly on the phase of the step cycle and reveals a functional clustering of Purkinje cells. Furthermore, we find a pronounced disassociation between patterns of variability driven by the parallel and climbing fibers. These results suggest that Purkinje cell activity not only represents step phase within each cycle but also is shaped by behavior across steps, facilitating control of movement under dynamic conditions

Use and misuse of aspirin in rural Ethiopia

Objectives: To investigate ability to distinguish simple analgesics, to document misconceptions about aspirin use, and to identify strategies to diminish potentially harmful aspirin use in Ethiopia. Design: Qualitative study (eight focus group discussions) used to inform cross-sectional survey. Setting: Butajira, a small town in southern Ethiopia, and surrounding rural areas. Participants: Purposively selected informants for focus groups; random sample of urban and rural residents for cross-sectional survey. Main outcome measures: Ability to distinguish aspirin from paracetamol; proportion using aspirin; proportion aware of common risks of aspirin. Results: Questionnaires were completed by 204 of the 250 residents sampled (82% response). Three-quarters of survey participants knew the difference between aspirin and paracetamol. Aspirin was used by 7.3% of respondents, and was mainly taken for headache and fever. In focus group discussions there was a suggestion that aspirin was considered particularly useful for children. There was very low awareness of the risks of using aspirin in children (2.5% unprompted, 18.6% prompted) or in people with asthma (1% unprompted, 5.9% prompted). Aspirin is cheap and widely available in urban and rural areas.Conclusion: Awareness of the risks of aspirin use by children and in asthma is extremely low in this rural Ethiopian setting. Medications are purchased with minimal packaging by a population with low literacy. Drug dispensers and vendors must be trained to convey simple verbal warnings about aspirin use. East African Medical Journal Vol. 83(1) 2006: 31-3

Intensity enhancement of O VI ultraviolet emission lines in solar spectra due to opacity

Opacity is a property of many plasmas, and it is normally expected that if an emission line in a plasma becomes optically thick, its intensity ratio to that of another transition that remains optically thin should decrease. However, radiative transfer calculations undertaken both by ourselves and others predict that under certain conditions the intensity ratio of an optically thick to thin line can show an increase over the optically thin value, indicating an enhancement in the former. These conditions include the geometry of the emitting plasma and its orientation to the observer. A similar effect can take place between lines of differing optical depth. Previous observational studies have focused on stellar point sources, and here we investigate the spatially-resolved solar atmosphere using measurements of the I(1032 A)/I(1038 A) intensity ratio of O VI in several regions obtained with the Solar Ultraviolet Measurements of Emitted Radiation (SUMER) instrument on board the Solar and Heliospheric Observatory (SoHO) satellite. We find several I(1032 A)/I(1038 A) ratios observed on the disk to be significantly larger than the optically thin value of 2.0, providing the first detection (to our knowledge) of intensity enhancement in the ratio arising from opacity effects in the solar atmosphere. Agreement between observation and theory is excellent, and confirms that the O VI emission originates from a slab-like geometry in the solar atmosphere, rather than from cylindrical structures.Comment: 17 pages, 4 figures, ApJ Letters, in pres

European Non-native Species in Aquaculture Risk Analysis Scheme - a summary of assessment protocols and decision support tools for use of alien species in aquaculture

The European Non-native Species in Aquaculture Risk Analysis Scheme (ENSARS) was developed in response to European 'Council Regulation No. 708/2007 of 11 June 2007 concerning use of alien and locally absent species in aquaculture' to provide protocols for identifying and evaluating the potential risks of using non-native species in aquaculture. ENSARS is modular in structure and adapted from non-native species risk assessment schemes developed by the European and Mediterranean Plant Protection Organisation and for the UK. Seven of the eight ENSARS modules contain protocols for evaluating the risks of escape, introduction to and establishment in open waters, of any non-native aquatic organism being used (or associated with those used) in aquaculture, that is, transport pathways, rearing facilities, infectious agents, and the potential organism, ecosystem and socio-economic impacts. A concluding module is designed to summarise the risks and consider management options. During the assessments, each question requires the assessor to provide a response and confidence ranking for that response based on expert opinion. Each module can also be used individually, and each requires a specific form of expertise. Therefore, a multidisciplinary assessment team is recommended for its completion

High resolution characterisation of microstructural evolution in Rbx_{x}Fe2−y_{2-y}Se2_{2} crystals on annealing

The superconducting and magnetic properties of phase-separated A$_x$Fe$_{2-y}$Se$_2$ compounds are known to depend on post-growth heat treatments and cooling profiles. This paper focusses on the evolution of microstructure on annealing, and how this influences the superconducting properties of Rb$_x$Fe$_2-y$Se$_2$ crystals. We find that the minority phase in the as-grown crystal has increased unit cell anisotropy (c/a ratio), reduced Rb content and increased Fe content compared to the matrix. The microstructure is rather complex, with two-phase mesoscopic plate-shaped features aligned along {113} habit planes. The minority phase are strongly facetted on the {113} planes, which we have shown to be driven by minimising the volume strain energy introduced as a result of the phase transformation. Annealing at 488K results in coarsening of the mesoscopic plate-shaped features and the formation of a third distinct phase. The subtle differences in structure and chemistry of the minority phase(s) in the crystals are thought to be responsible for changes in the superconducting transition temperature. In addition, scanning photoemission microscopy has clearly shown that the electronic structure of the minority phase has a higher occupied density of states of the low binding energy Fe3d orbitals, characteristic of crystals that exhibit superconductivity. This demonstrates a clear correlation between the Fe-vacancy-free phase with high c/a ratio and the electronic structure characteristics of the superconducting phase.Comment: 6 figures v2 is exactly the same as v1. The typesetting errors in the abstract have been correcte

Lactose and benign ovarian tumours in a case–control study

We investigated the relation between benign ovarian tumours and lactose among 746 case women identified at seven New York metropolitan hospitals and 404 community controls, age and hospital frequency matched to the expected case distribution. No increase in risk was found for lactose (highest quartile versus lowest: adjusted odds ratio = 0.82 (95% CI 0.57–1.20) or for any other lactose foods. © 2000 Cancer Research Campaign http://www.bjcancer.co