bluuebunny/crossref_metadata_2025 huggingface dataset:
The analysis of single-electron orbits in a free electron laser based upon a rectangular hybrid wiggler
Authors: Kordbacheh A. , Ghahremaninezhad Roghayeh , Maraghechi B.
Published: September 2012

A three-dimensional analysis of a novel free-electron laser (FEL) based upon a rectangular hybrid wiggler (RHW) is presented. This RHW is designed in a configuration composed of rectangular rings with alternating ferrite and dielectric spacers immersed in a solenoidal magnetic field. An analytic model of RHW is introduced by solution of Laplace's equation for the magnetostatic fields under the appropriate boundary conditions. The single-electron orbits in combined RHW and axial guide magnetic fields are studied when only the first and the third spatial harmonic components of the RHW field are taken into account and the higher order terms are ignored. The results indicate that the third spatial harmonic leads to group III orbits with a strong negative mass regime particularly in large solenoidal magnetic fields. RHW is found to be a promising candidate with favorable characteristics to be used in microwave FEL.
Combined versatile high-resolution optical tweezers and single-molecule fluorescence microscopy
Authors: Sirinakis George , Ren Yuxuan , Gao Ying , Xi Zhiqun , Zhang Yongli
Published: September 2012

Optical trapping and single-molecule fluorescence are two major single-molecule approaches. Their combination has begun to show greater capability to study more complex systems than either method alone, but met many fundamental and technical challenges. We built an instrument that combines base-pair resolution dual-trap optical tweezers with single-molecule fluorescence microscopy. The instrument has complementary design and functionalities compared with similar microscopes previously described. The optical tweezers can be operated in constant force mode for easy data interpretation or in variable force mode for maximum spatiotemporal resolution. The single-molecule fluorescence detection can be implemented in either wide-field or confocal imaging configuration. To demonstrate the capabilities of the new instrument, we imaged a single stretched λ DNA molecule and investigated the dynamics of a DNA hairpin molecule in the presence of fluorophore-labeled complementary oligonucleotide. We simultaneously observed changes in the fluorescence signal and pauses in fast extension hopping of the hairpin due to association and dissociation of individual oligonucleotides. The combined versatile microscopy allows for greater flexibility to study molecular machines or assemblies at a single-molecule level.
Macrospin and micromagnetic studies of tilted polarizer spin-torque nano-oscillators
Authors: Zhou Yan , Zhang Hong , Liu Yaowen , Åkerman Johan
Published: September 2012

Using nonlinear dynamical systems theory, we analytically studied a spin-torque device in which the magnetization of the polarizer (the fixed layer) is tilted at an arbitrary angle out of the thin-film plane. While the analytical theory can determine the major features of the system, macrospin simulations were employed to demonstrate the unique characteristics of the system, such as the hysteretic switching between bistable states. Material dependencies of the dynamic and static state diagrams were also studied in the framework of the macrospin model. Full-scale micromagnetics simulations were finally performed to reveal more subtle features of the dynamics of such tilted polarizer systems. Both the macrospin and micromagnetics simulations gave quantitatively the same results as our analytical theory.
Ultrafast solvation response in room temperature ionic liquids: Possible origin and importance of the collective and the nearest neighbour solvent modes
Authors: Daschakraborty Snehasis , Biswas Ranjit
Published: September 2012

Recent three-pulse photon echo peak shift (3PEPS) measurements [M. Muramatsu, Y. Nagasawa, and H. Miyasaka, J. Phys. Chem. A 115, 3886 (2011)]10.1021/jp108282v with several room temperature ionic liquids (RTILs) have revealed multi-exponential dynamics with ultrafast solvation timescale in the range, 20 < τ1/fs < 250, for both imidazolium and phosphonium RTILs. This is striking for two reasons: (i) the timescale is much faster than those reported by the dynamic Stokes shift (DSS) experiments [S. Arzhantsev, H. Jin, G. A. Baker, and M. Maroncelli, J. Phys. Chem. B 111, 4978 (2007)]10.1021/jp067273m and (ii) sub-hundered femtosecond solvation response in phosphonium ionic liquids is reported for the first time. Here, we present a mode coupling theory based calculation where such ultrafast solvation in 3PEPS measurements has been visualized to originate from the nearest neighbour solute-solvent interaction. Consideration of Lennard-Jones interaction for the nearest neighbour solute-solvent non-dipolar interaction leads to biphasic dynamics with a predicted ultrafast time constant in the ∼100–250 fs range, followed by a slower one similar to that reported by the 3PEPS measurements. In addition, the calculated fast time constants and amplitudes are found to be in general agreement with those from computer simulations. Different microscopic mechanisms for ultrafast solvation response measured by the 3PEPS and DSS experiments have been proposed and relative contributions of the collective and nearest neighbour solvent modes investigated. Relation between the single particle rotation and ultrafast polar solvation in these RTILs has been explored. Our analyses suggest 3PEPS and DSS experiments are probably sensitive to different components of the total solvation energy relaxation of a laser-excited dye in a given ionic liquid. Several predictions have also been made, which may be re-examined via suitable experiments.
Effects of substrate and N content on the growth of the mid-infrared dilute nitride InAsN alloy
Authors: de la Mare M , Zhuang Q , Patanè A , Krier A
Published: September 2012

We investigate the epitaxial growth of the dilute nitride InAsN alloy onto InAs and GaAs substrates with nitrogen content up to 1%. We report photoluminescence (PL) emission within the 2–4 µm spectral region and show that InAsN grown onto GaAs exhibits no degradation of the PL intensity and linewidth compared with epitaxial layers grown on near lattice-matched InAs substrates. Also, nitrogen can induce a significant reduction in the thermal quenching of the PL emission, which we attribute to the reduction in non-radiative Auger-recombination.
Rapid thermal annealed WO3-doped In2O3 films for transparent electrodes in organic photovoltaics
Authors: Kim Jun Ho , Shin Yong-Hee , Seong Tae-Yeon , Na Seok-In , Kim Han-Ki
Published: September 2012

We investigated the effect of rapid thermal annealing (RTA) on the electrical, optical, structural and surface properties of WO3-doped In2O3 (IWO) films for use in organic solar cells (OSCs). Increasing the RTA temperature led to significant decreases in resistivity and sheet resistance due to activation of the W dopants and the (2 2 2) preferred orientation of the IWO films. At the optimized RTA temperature of 500 °C, the IWO film had a sheet resistance of 21 Ω/square and an optical transmittance of 89.39%, which is comparable to conventional ITO electrodes. Due to the high mobility of 46 cm2 V−1 s−1, the IWO film showed a higher optical transmittance in the near infrared wavelength region even though it had a low resistivity of 4.34 × 10−4 Ω cm. Furthermore, the 500 °C annealed IWO film showed very smooth surface morphology due to its (2 2 2) preferred orientation. The performance (fill factor of 61.59%, short circuit current of 8.84 mA cm−2, open circuit voltage of 0.60 V and power conversion efficiency of 3.27%) of the OSC fabricated with the IWO electrode was nearly identical to that of the OSC with a reference ITO anode, indicating that the IWO anode is a promising high-mobility transparent electrode material to replace conventional ITO anodes for high-performance OSCs.
Dielectric recovery in a high-voltage circuit breaker in SF6
Authors: Seeger M , Schwinne M , Bini R , Mahdizadeh N , Votteler T
Published: September 2012

The dielectric recovery in high-voltage circuit breakers after interruption of high-current amplitudes was investigated experimentally in a test device. Various current amplitudes were tested, which cover a typical range of practical interest. Simulations with computational fluid dynamics together with electric field simulations allowed one to deduce the physical parameters in the region where the breakdown was decided. A leader inception model using these parameters explains under which condition leader inception occurs; causing breakdown of the gap. Based on this model scaling laws for leader inception are given.
Environmentally induced dispersal‐related life‐history syndrome in the tropical butterfly, Bicyclus anynana
Authors: Saastamoinen M. , Brakefield P. M. , Ovaskainen O.
Published: September 2012

Dispersal is a key process for understanding the persistence of populations as well as the capacity of organisms to respond to environmental change. Therefore, understanding factors that may facilitate or constrain the evolution of dispersal is of crucial interest. Assessments of phenotypic variation in various behavioural, physiological and morphological traits related to insect dispersal and flight performance are common, yet very little is known about the genetic associations among these traits. We have used experiments on the butterfly Bicyclus anynana to estimate genetic variation and covariation in seven behavioural, physiological and morphological traits related to flight potential and hence dispersal. Our goal was to characterize the heritabilities and genetic correlations among these traits and thus to understand more about the evolution of dispersal‐related life‐history syndromes in butterflies. Using a version of the animal model, we showed that all of the traits varied between the sexes, and most were either positively or negatively (phenotypically and/or genetically) correlated with body size. Heritable variation was present in most traits, with the highest heritabilities estimated for body mass and thorax ratio. The variance in flight activity among multiple measurements for the same individual was high even after controlling for the prevailing environmental conditions, indicating the importance of behavioural switching and/or inherent randomness associated with this type of movement. A number of dispersal‐related traits showed phenotypic correlations among one another, but only a few of these were associated with significant genetic correlations indicating that covariances between these traits in Bicyclus anynana are mainly environmentally induced.
The Effects of Reduced Social Security Contributions on Employment: An Evaluation of the 2003 French Reform*
Authors: Bunel Mathieu , L'Horty Yannick
Published: September 2012

In 2003, the French government decided to reform the system managing the different minimum wage regulations and the targeted reductions to employers' social security contributions. The main objective of the Fillon reform was to simplify the complex regulations that were created by the progressive introduction of the 35‐hour week. The reform incidentally created large variations in labour costs, depending on the type of firm and the wage level within the firm. This paper presents an evaluation of the impact of this reform on employment using a balanced panel of firms with more than five employees, drawn from a matching between several administrative data sources from 2000 to 2005.
Clinical Care of Persons with Dementia in the Emergency Department: A Review of the Literature and Agenda for Research
Authors: Clevenger Carolyn K. , Chu Thasha A. , Yang Zhou , Hepburn Kenneth W.
Published: September 2012

The segment of older adults who present to the emergency department (ED) with cognitive impairment ranges from 21% to 40%. Difficulties inherent in the chaotic ED setting combined with dementia may result in a number of unwanted clinical outcomes, but strategies to minimize these outcomes are lacking. A review of the literature was conducted to examine the practices undertaken in the care of persons with dementia (PWD) specific to the ED setting. PubMed and Cumulative Index to Nursing and Allied Health Literature were searched for published articles specific to the care of PWD provided in the ED. All English‐language articles were reviewed; editorials and reflective journals were excluded. Seven articles ultimately met inclusion criteria; all provided Level 7 evidence: narrative review or opinions from authorities. The articles recommended clinical practices that can be categorized into five themes: assessment of cognitive impairment, dementia communication strategies, avoidance of adverse events, alterations to the physical environment, and education of ED staff. Many recommendations are extrapolated from residential care settings. Review results indicate that there is minimal guidance for the care of PWD specific to the ED setting. There are no empirical studies of the care (assessment, interventions) of PWD in the ED. The existing (Level 7) recommendations lack a research base to support their effectiveness or adoption as evidence‐based practice. There is a significant opportunity for research to identify and test ways to meet the needs of PWD in the ED to ensure a safe visit, accurate diagnosis, and prudent transfer to the most appropriate level of care.
Where Deer Roam: Chronic Yet Acute Site Exposures Preclude Ecological Risk Assessment
Authors: Tannenbaum Lawrence V. , Gulsby William D. , Zobel Shaina S. , Miller Karl V.
Published: September 2012

Global positioning system (GPS) technology has made possible the detailed tracking of the spatial movements of wildlife. Using GPS tracking collars placed on female white‐tailed deer (Odocoileus virginianus) over a protracted period, we illustrate that this species is spatially irrelevant for consideration in ecological risk assessments (ERAs) for commonly assessed contaminated sites. Specifically, deer movements do not allow for a sufficiency of chemical exposures to occur such that toxicological endpoints would be triggered. Deer are spatially irrelevant not only because their home ranges and overall utilized areas dwarf prototypical hazardous waste sites. They are also inappropriate for assessment because they only minimally contact reasonably sized preferred locations, this while demonstrating a confounding high degree of site affinity for them. Our spatial movements analysis suggests that deer introduce the ERA novelty of a species displaying elements of both chronic and acute site exposure. We further suggest that other large commonly assessed high‐profile mammals could also be found to be spatially irrelevant for ERAs were they to submit to the GPS tracking and subsequent data analysis we performed for the deer. Recognizing that certain receptors need not be considered in ERAs can help to simplify the ERA process.
Prenatal Representations of Coparenting Among Unmarried First‐Time African American Mothers
Authors: Gaskin‐Butler Vikki T. , Engert Tina , Markievitz Meredith , Swenson Camielle , McHale James
Published: September 2012

Results of semistructured interviews with 45 pregnant unmarried first‐time African American mothers indicated a wide range of expectancies concerning the coparenting relationship they would develop with others once their baby arrived. Most common coparenting systems projected by respondents involved maternal grandmothers and/or the babies' fathers, though other caregivers were explicitly anticipated in a smaller number of cases. Multiperson coparenting systems were the norm, and only 2 of 45 respondents anticipated that they would be entirely on their own with no coparental system whatsoever. Qualitative analyses of mothers' narratives about postbaby coparenting systems revealed five main constructions: having thought about and anticipating coparenting, positive in outlook; having thought about and anticipating coparenting, but with mild concerns (conflict, unreliability); having thought about coparenting and anticipating limited or no support; having thought about coparenting and anticipating significant conflict and nonsupport; and having not thought much about coparenting, being neither focused on nor worried about this issue. Illustrations of each of these types are provided, and directions for family science and practice are discussed.
Low‐paid employment in Brazil
Authors: FONTES Adriana , PERO Valéria , BERG Janine
Published: September 2012

While low pay is prevalent in developing countries, the issue has not been studied in depth. To help fill this gap, the authors use panel data on six Brazilian metropolitan areas for the years 2002–09 to investigate the incidence, permanence and profile of low‐paid employment. Over the period, low‐paid work declined from 24.4 to 21.5 per cent of total wage employment. As in high‐income countries, the probability of being low‐paid was greater for women, non‐whites, younger workers and those with fewer years of education. A mobility analysis shows that job experience improved labour market prospects, even for low‐paid wage earners.
Thalidomide: features and potential significance in oral precancerous conditions and oral cancer
Authors: Jin Xin , Lu Shujing , Xing Xue , Wang Lili , Mu Dongliang , He Mingjing , Huang Haiyun , Zeng Xin , Chen Qianming
Published: September 2012

Background

Thalidomide was originally marked as a sedative and anti‐emetic, but was withdrawn after severe teratogenic effects had been discovered. More recently it has been claimed to alleviate a wide range of inflammatory disorders and malignancies. Studies showed that thalidomide might play a role in the management of some oral premalignant conditions and its potential to be an adjunct in the prevention of oral cancer.

Aim

The aim of this study is to summarize the characteristics and feasibility of thalidomide in the development and prevention of oral precancerosis, and to draw attentions of researchers to its therapeutic potential in oral cancer.

Methods

Databases were searched on the basis of PubMed and EMbase. Thalidomide associated with the oral lichen planus, chronic discoid lupus erythematosus (CDLE) and oral cancer were assessed.

Results

We have summed up the structure and pharmacokinetics of thalidomide, possible role of thalidomide in cancer prevention, as well as the recent data concerning its effects in prevention of oral premalignant conditions and potential for the treatment of oral cancer.

Conclusions

Therapeutic effects of thalidomide in oral lichen planus and CDLE have been discussed by clinical trials. And increasing evidences from in vitro and in vivo experiments show that thalidomide is a promising anticancerous agent for oral cancer, which should be paid attention to. It is necessary to perform more studies and clinical trials of large sample size to clarify underlying mechanisms and demonstrate the potential roles of thalidomide in clinical routine management of oral diseases.
A Common Clathrin‐Mediated Machinery Co‐ordinates Cell–Cell Adhesion and Bacterial Internalization
Authors: Bonazzi Matteo , Kühbacher Andreas , Toledo‐Arana Alejandro , Mallet Adeline , Vasudevan Lavanya , Pizarro‐Cerdá Javier , Brodsky Frances M. , Cossart Pascale
Published: September 2012

Invasive bacterial pathogens often target cellular proteins involved in adhesion as a first event during infection. For example, Listeria monocytogenes uses the bacterial protein InlA to interact with E‐cadherin, hijack the host adherens junction (AJ) machinery and invade non‐phagocytic cells by a clathrin‐dependent mechanism. Here, we investigate a potential role for clathrin in cell–cell adhesion. We observed that the initial steps of AJ formation trigger the phosphorylation of clathrin, and its transient localization at forming cell–cell contacts. Furthermore, we show that clathrin serves as a hub for the recruitment of proteins that are necessary for the actin rearrangements that accompany the maturation of AJs. Using an InlA/E‐cadherin chimera, we show that adherent cells expressing the chimera form AJs with cells expressing E‐cadherin. We demonstrate that non‐adherent cells expressing the InlA chimera, as bacteria, can be internalized by E‐cadherin‐expressing adherent cells. Together these results reveal that a common clathrin‐mediated machinery may regulate internalization and cell adhesion and that the relative mobility of one of the interacting partners plays an important role in the commitment to either one of these processes.
Planning Nonsingular Transitions Between Solutions of the Direct Kinematic Problem From the Joint Space
Authors: Macho Erik , Petuya Victor , Altuzarra Oscar , Hernandez Alfonso
Published: September 2012

The aim of this paper is to describe a general and systematic methodology to make controllable transitions between different solutions of the direct kinematic problem (DKP) from the joint space. This work is focused on parallel manipulators and the goal is the usage of just the input variables domain. This way, such transitions can be made controlling all the inputs simultaneously at all times. To do so, it is necessary to analyze the locus of direct kinematics singularities, where different direct kinematic solutions coalesce. It is necessary to specify which portions of such a locus specifically affect each solution. This analysis requires obtaining the locus of triple coalescence singularities. Having done this, all the information can be processed in order to obtain several maps in the joint space. Finally, it will establish the strategy on how to use these maps to connect desired solutions, including the application to a representative example.
OP12 Childhood Infectious Disease and Risk of Premature Death from Cancer: A Prospective Cohort Study
Authors: Tennant PWG , Parker L , Thomas JE , Craft AW , Pearce MS
Published: September 2012

Background

The hygiene-hypothesis proposes that early-life infectious diseases may protect against a number of adverse health conditions later in life, most notably the development of cancer. Existing investigations of this association, however, have provided equivocal results, possibly due to inadequate adjustment for confounding or the use of retrospective exposure information. This study utilised longitudinal data from the Newcastle Thousand Families Study, a prospective cohort of 1147 individuals born in Newcastle-upon-Tyne (UK) in 1947, to assess the impact of various childhood infectious diseases on death from cancer between ages 15 and 60 years.

Methods

Detailed information was collected prospectively at birth and during childhood on a number of early life factors. Episodes of illness during the first 15 years were obtained routinely by health visitors, who regularly visited the participants’ homes, or directly from the family doctor or hospital. All study members were ‘flagged’ by the UK National Health Service Central Register when they died or emigrated. Deaths from cancer between ages 15 to 60 years were analysed in relation to childhood infections, adjusting for potential early-life confounders, using Cox proportional-hazards regression.

Results

Of the 1060 study members known to be alive at age 15 years, 88 died before aged 60 years, including 37 from cancer – the leading cause of death. Childhood history of measles and childhood history of influenza, were both independently associated with a lower risk of death from cancer during ages 15 to 60 years (influenza: adjusted hazard ratio, aHR=0.39, 95% CI: 0.17–0.88, p=0.03; measles: aHR=0.49, 95% CI: 0.24–0.98, p=0.04). In contrast, childhood history of whooping cough was associated with a higher risk of death from cancer during ages 15 to 60 years (adjusted HR, aHR=4.88, 95% CI: 2.29–10.39, p<0.0001). The association between whooping cough and cancer-related mortality was borderline significantly different between men and women (p=0.05), with a stronger association among women than men (women: aHR=12.20, 95% CI: 3.01–49.42, p=0.0005; men: aHR=2.10, 95% CI: 0.80–5.50, p=0.13).

Conclusion

In a pre-vaccination cohort from the North of England, childhood infection with measles and influenza were associated with a reduced risk of death from cancer in adulthood, while childhood whooping cough was associated with an increased risk. These results suggest that there may be some disease-specific associations between childhood infectious diseases and death from adult cancer, however further studies are required to confirm the specific associations identified.
OP28 Diet Quality and Blood Pressure in Middle-Aged Men and Women
Authors: Harrington J , Fitzgerald AP , Kearney PM , McCarthy VJC , Browne G , Perry IJ
Published: September 2012

Background

Findings from both observational and experimental studies (including the DASH Trial -Dietary Approaches to Stop Hypertension) are consistent with a significant, causal role for dietary salt intake in the distribution of blood pressure (BP) in populations. The DASH diet quality score, based on the intervention arm in the DASH-trial, has emerged as a potentially useful measure of diet quality in adult populations. We have studied associations between DASH score and blood pressure, both clinic and 24 hour ambulatory measurements (ABPM) in middle-aged men and women.

Methods

We used cross-sectional data from two studies of men and women aged 50 to 69 years, recruited in 1998 (n=1018) and 2010 (n=2047). Participants completed a physical examination including three standardised clinical BP recordings and a general health and lifestyle questionnaire. A sub-sample (n=1189) in 2010 had 24hr ambulatory BP measurements (ABPM). Diet quality was assessed using a DASH score constructed from a standardised Willett FFQ. DASH scores were categorised into quintiles, with lower quintiles indicating less healthy diets. Hypertension was defined as clinic BP>140/90mmHg (mean of readings 2 and 3) and 24-hour ABPM >130/70mmHg.

Results

Clear inverse trends were seen between DASH scores and systolic (SBP) and diastolic (DBP) BP in clinic and ABPM recordings. The associations between DASH score and clinic BP were similar in the 1998 and 2010 datasets. In the 2010 data, clinic SBP increased by 7.5 mmHg in men and 5.1 mmHg in women between the highest and lowest DASH quintiles and 24-hour ABPM systolic BP increased by 6.3mmHg and 5.4mmHg in men and women respectively between the highest and lowest DASH quintiles. In fully adjusted analyses, the odds ratios (OR) for clinic hypertension and ABPM hypertension in participants with DASH score in the first relative to the fifth DASH score quintile were as follows: clinic hypertension: OR 1.60 (95% CI 0.9–2.8), ABPM hypertension: OR 4.2; 95 % CI [1.1–15.9]). Stratifying by gender, these trends persisted for men however they were attenuated for women.

Conclusion

This study provides evidence of criterion validity for the use of DASH score as a measure of diet quality, especially in the diet-hypertension relationship in men. Our findings are consistent with the hypothesis that dietary patterns exert effects beyond the sum of the component parts. Public policy promoting a DASH-style healthy diet could have a significant impact on population health by reducing average blood pressure in the population.
OP29 Ethnic and Socioeconomic Influences on Childhood Blood Pressure: The Child Heart and Health Study in England (Chase)
Authors: Thomas C , Nightingale CM , Donin A , Rudnicka AR , Owen CG , Cook D , Whincup PH
Published: September 2012

Background

Compared to UK white European adults, UK black African-Caribbean adults have higher mean systolic (SBP) and diastolic (DBP) blood pressure; UK South Asian adults have higher mean DBP but lower SBP. However, information on blood pressure in UK children from different ethnic groups is limited. The aim of this study was to compare blood pressure levels in UK children of black African-Caribbean, South Asian and white European origin.

Methods

A cross sectional study of 5,666 UK primary school children of South Asian, black African Caribbean, and white European origin aged 9 to 10 years was undertaken. Ethnic and socioeconomic differences in SDP and DBP (as means and differences with their 95% confidence intervals) were obtained from multilevel linear regression models fitting school as a random effect in order to take account of the natural clustering of children within school. All analyses were adjusted for sex, age, month of assessment, blood pressure observer, room temperature and time of day of measurement fitted as fixed effects. The effects of adjustment for height, adiposity (fat mass index, sum of skinfolds) fitted as continuous variables, and socioeconomic circumstances on ethnic differences in blood pressure were then explored.

Results

After adjustment for height and adiposity, black African-Caribbean children had a lower mean SBP than white Europeans (mean difference 1.62 mmHg, 95% CI 0.86, 2.38 mmHg), while mean DBP was similar (mean difference 0.58 mmHg, 95%CI –0.12, 1.28 mmHg). The mean SBP difference was particularly marked in black African children. In similar analyses, South Asian children had a lower mean SBP (mean difference 1.10 mmHg, 95%CI 0.34, 1.86 mmHg) than white Europeans and a higher mean DBP (mean difference 1.07 mmHg, 95%CI 0.37, 1.76 mmHg). The mean DBP difference was particularly marked among Indian and Bangladeshi, rather than Pakistani, children. Blood pressure was largely unrelated to socioeconomic circumstances; the ethnic differences in blood pressure were not affected by socioeconomic adjustment.

Conclusion

A blood pressure pattern similar to that in adults is present in UK South Asian but not in UK black African-Caribbean children at 9–10 years. This suggests that key determinants of ethnic differences in blood pressure operate at different stages of the life course in these different ethnic groups. Understanding the reasons for the early emergence of ethnic differences in blood pressure (particularly among South Asians) is an important research priority.
OP30 Are the Associations Between Adiposity, Insulin Resistance and Circulating Glucose Concentrations in Childhood Influenced by Ethnicity? Evidence from the Child Heart and Health Study in England (CHASE)
Authors: Nightingale CM , Rudnicka AR , Owen CG , Sattar N , Cook DG , Whincup PH
Published: September 2012

Background

Ethnic differences in type 2 diabetes risk between South Asians and white Europeans originate before adult life. Although South Asian adults have greater metabolic sensitivity to adiposity this has been little studied in childhood. We have therefore examined the associations between adiposity, insulin and glycated haemoglobin (HbA1c) levels in children of South Asian and white European origin. Data on children of black African-Caribbean origin are also reported.

Methods

This was a cross-sectional school-based study of 4633 nine and ten year-old children (response rate 68%) predominantly of South Asian, black African-Caribbean and white European origin. Participants had detailed assessments of adiposity (including body mass index, skinfold thicknesses and fat mass index from bioimpedance) and provided fasting blood samples for assessment of HbA1c and insulin resistance (Homeostatic model assessment-insulin resistance; HOMA-IR). Associations between HOMA-IR (log transformed), HbA1c and adiposity markers were estimated using multilevel linear regression.

Results

All adiposity measures were positively associated with insulin resistance in all ethnic groups. However there were clear ethnic differences in the strength of association (p ethnic difference <0.001). The percentage increase in HOMA-IR for a one SD increase in fat mass index was 36.3% (95% CI 32.1%, 40.5%) for South Asians and 25.1% (95% CI 21.1%, 29.3%) for white Europeans; black African-Caribbeans were similar to white Europeans (26.4%, 95% CI 22.5%, 30.4%). All adiposity markers were positively associated with HbA1c in both South Asians and black African-Caribbeans: the percentage increase in HbA1c for a one SD increase in fat mass index in was 0.04% (95% CI 0.02%, 0.06%) in both ethnic groups. However there was no association among white Europeans (0.01%, 95% CI 0.00%, 0.03%).

Conclusion

Even in childhood, both insulin resistance and HbA1c levels appear more sensitive to adiposity in South Asians. Among children of black African-Caribbean origin, HbA1c levels but not insulin resistance appear more sensitive to adiposity. The reasons for these differences in sensitivity to adiposity need to be understood. The results imply that early prevention of childhood obesity among South Asians and black African-Caribbeans is a particular priority for future control of type 2 diabetes in these high risk ethnic groups.
OP31 Ethnic Differences in the Development of Disability Over 20 Years: Results from the Sabre Study
Authors: Williams ED , Tillin T , Chaturvedi N
Published: September 2012

Background

As life expectancy increases, healthy ageing becomes more salient, and therefore it is important to understand how conditions such as disability may affect the later years of our extended lives. Ethnic differences in disability have been observed in some countries, however there is a lack of evidence from British ethnic groups.

Methods

Follow-up data over 20 years from 1789 White, Indian Asian and African Caribbean men and women were examined from a community-based study in West London. Disability was measured using the performance-based test of locomotor function and self-reported functional limitation, instrumental and basic activities of daily living (IADL/ADL) questionnaires. Logistic regression analyses examined ethnic group differences in disability, adjusting for socioeconomic, behavioural, adiposity and chronic disease risk factors.

Results

After full adjustment, Indian Asian people were significantly more likely to have developed all of the disability outcomes, compared with UK Whites (locomotor dysfunction: OR 2.20, 95% CI 1.56–3.11; functional limitation: OR 2.77, 2.01–3.81; IADL impairment: OR 3.12, 2.20–4.41; ADL impairment: OR 1.56, 1.11–2.24). Health behaviours, central adiposity, and chronic disease burden explained only a proportion of this excess risk. There were no ethnic group differences in locomotor dysfunction, functional limitation and IADL impairment between African Caribbean and White participants, however African Caribbean people showed a reduced risk of ADL impairment (OR 0.59, 0.38–0.93), after multivariate adjustment.

Conclusion

These findings demonstrate dramatic ethnic group differences in performance-based and self-reported disability between White, Indian Asian, and African Caribbean people in the UK. The excessive risk experienced by Indian Asian people was partly explained by health behaviours, adiposity, and chronic disease, however considerable inequalities remained. Other possible explanations for this vulnerability to disability among Indian Asian people will be discussed. Such inequalities are likely to have a detrimental impact on quality of life and morbidity in later years, and therefore, more research is urgently needed to understand these large ethnic inequalities in disability.
OP38 Accounting for Non-Uptake of Bowel Cancer Screening: A Qualitative Study
Authors: Palmer C , Thomas M , Raine R , Wagner C Von
Published: September 2012

Background

Since being established in 2006, the English NHS Bowel Cancer Screening Programme (NHS BCSP) offers the faecal occult blood (FOB) test to adults aged 60 – 74. This bowel cancer screening test is sent by post every two years to recipients who are required to provide six small samples of faeces from three bowel movements. The kit is returned by post to be tested for minute traces of blood that may be an early warning sign for the development of bowel cancer. Analysis shows that approximately 53% of people offered bowel cancer screening by FOB test take it up, and that uptake varies from 35% to 60% in the most and least deprived areas, respectively.

Methods

We used a qualitative approach to explore views and experiences about bowel cancer screening in people who did not take part in the screening programme when invited to do so. We conducted 16 focus groups in London and South Yorkshire to generate extensive textual data, and analysed our data thematically using grounded theory techniques to explore and examine accounts of non-uptake. Previous research examining ‘non-uptake’, of this and other medical interventions has identified considerable challenges in terms of identifying and recruiting individuals who may be defined in this way. We therefore used a novel recruitment approach, working with the National BCSP Hubs to identify and recruit ‘non-uptakers’ of bowel cancer screening. We present the findings from our thematic analysis of 16 focus groups undertaken with people who did not participate in bowel cancer screening and explore the complexity of ‘non-uptakers’’ accounts.

Results & Conclusion

During preliminary analyses, we identified common accounts through which participants rationalised non-uptake and which present one or several barriers to undertaking bowel cancer screening. Participants rationalised their non-uptake of screening in a number of ways, for example by making reference to perceptions of low personal risk informed by ‘feeling well’ or having had no family history of bowel cancer. Others expressed sophisticated doubts about the benefits or value of the FOB test specifically, or in relation to diagnostic or treatment interventions for cancer more generally. Finally, the necessity to provide samples of faeces to complete the FOB test emerged repeatedly as a troubling aspect of the bowel cancer screening methodology offered by the English NHS BCSP.
OP39 Protection by BCG Against Tuberculosis: Systematic Review and Meta-Regression Analysis
Authors: Mangtani P , Ariti C , Rodrigues L , Abubakar I , Pimpin L , Fine P , Smith P , Sterne J
Published: September 2012

Setting

Reasons for variation in BCG protection against tuberculosis are not well understood. We therefore estimated the protection provided by BCG vaccination against tuberculosis and examined reasons for variation in different settings.

Methods

We systematically searched English and non-English articles in 10 databases from inception to May 2009 as well as sources such as Google Scholar and trial registers to October 2009. Search terms included tuberculosis, tubercle bacill*,M. tuberculosis,M. bovis,M. africanum,M. canetti,M. microtiandM. tuberculosis. Terms for the intervention included BCG Vaccine, BCG, BCG Vacc*, BCG Imm*, bacillus calmette.

Two reviewers independently screened studies for inclusion. Data (including results and domains of study quality) were extracted by one reviewer and checked by another. Pooled analyses were based on random and fixed effects meta-analysis. Heterogeneity was quantified using tau-squared (t2) statistics. Random-effects meta-regression was used to investigate associations of study characteristics with intervention effect estimates.

Results

Of 21,030 references we identified 21 trials reporting tuberculosis outcomes. Protection against tuberculosis disease was variable (t2=0.292). BCG efficacy was high at higher latitude or when BCG was given only to infants (62%, 95% CI 48–72%) or to children after strict screening for tuberculin sensitivity (72% 95% CI 60–81%) Protection against meningeal and miliary tuberculosis combined was higher in infants (90%) and children with stringent testing respectively (92%). The observed protective effect of BCG did not differ by the strain of BCG vaccine used. Stringency of tuberculin testing to exclude those infected or sensitised to mycobacteria explained a good proportion of the observed variation with latitude (t2=0.292 in the null model, 0.100 in the bivariate model). In a multivariable meta-regression analysis there was strong evidence that infant vaccination or stringent prior tuberculin testing before BCG in childhood was associated with increased efficacy (p=0.02) after taking into account latitude and a measure of study quality-diagnostic detection bias.

Conclusion

BCG protection against tuberculosis varies between settings to an extent which cannot be attributed to chance alone. More efficacious results were seen in studies of individuals screened using stringent criteria (to exclude those already sensitized to mycobacteria), and those at a greater latitude from the equator.
OP43 Are we Overestimating the Beneficial Effects of Alcohol in Later Life? the Case of Young Non-Drinkers
Authors: Fat L Ng
Published: September 2012

Background

Non-drinkers have been repeatedly shown to have worse health than moderate drinkers in later life particularly as regards conditions such as coronary heart disease, leading some researchers to suggest that moderate alcohol consumption has beneficial effects on health. However the causal direction between non-drinking and worse health has been contested. Whether poor health is associated with non-drinking among young adults in relation to social and health factors will be investigated. Such a finding would imply that poor health may precede non-drinking even at early stages of the life course.

Methods

We performed logistic regression analysis of cross-sectional national survey data on 18 to 34 year olds, collected from The Health Survey for England 2006 and 2008. Data was collected through face to face interviews and is self-reported. Logistic regression analysis of longitudinal data collected from the National Child Development Study 1958 were also conducted. This is a follow up study to assess whether poor health at age 16 is associated with non-drinking at age 23, and whether these people are more likely to abstain at subsequent age sweeps.

Results

HSE 06 & 08: Having a limiting longstanding illness during early adulthood increased the odds of being a non-drinker 1.74 times for men (p<0.01), and 1.45 times for women (p<0.01). In both men and women belonging to the lowest income quintile or having no qualifications was associated with increased odds of being a non-drinker (p<0.001) indicating that the social gradient in non-drinking begins at an early age. Men and women aged 18 to 34 years with the lowest activity levels were also more likely to be non-drinkers (p<0.01).

NCDS: Preliminary analysis reveals that non-drinkers at age 23 have higher rates of medical conditions at age 16 as assessed by a medical officer such as having a mental condition (p<0.001) a physical condition and heart and haematological condition (p<0.01).

Conclusion

Young adults who have a limiting longstanding illness are more likely not to drink alcohol even after adjusting for a range of social and demographic measures. Studies on the putative health benefits of moderate alcohol consumption later in life need to take account of early life history. Further analysis using longitudinal data will explore whether poor health precedes non-drinking right at the start of drinking history and whether people with poor health continue to abstain from alcohol at older ages.
OP54 Short-Term Impact of the Smokefree Legislation in England on Hospital Admissions for Asthma Among Adults
Authors: Sims M , Gilmore A
Published: September 2012

Background

Comprehensive smokefree laws prohibiting smoking in enclosed public places and workplaces have now been introduced in several jurisdictions and there is a growing body of evidence documenting the immediate health benefits to adults, focusing primarily on hospital admissions for heart attacks. A few studies have examined the association between smokefree laws and asthma in adults, but these have limitations such as lacking appropriate adjustment for long-term trends, or having limited statistical power due to a small study population. In this study we investigated the short-term impact of the introduction of smokefree legislation in England on 1st July 2007 on hospital admissions for asthma in adults.

Methods

The immediate effect of the legislation was investigated using monthly numbers of emergency admissions for asthma (primary diagnosis, ICD–10 code J45 and J46) in the nine Government Office Regions from April 1997 to December 2010, in the population aged 16 and over. The analysis was conducted using a quasi-Poisson generalised additive model that adjusted for seasonality and region-specific, non-linear, long-term trends.

Results

After adjusting for the long-term trend in admissions, we observed a 4.9% (95% CI: 0.6, 9.0) reduction in admissions for asthma immediately after introduction of smokefree legislation in the population as a whole. This implies that almost 1900 emergency admissions for asthma were prevented during the first year of the legislation. The reduction in admissions did not vary significantly across regions.

Conclusion

Our finding, based on the largest study to date, adds to the expanding body of evidence that smokefree legislation is associated with positive health outcomes. Further research evaluating the impact of legislation on asthma admissions in other jurisdictions is needed in order to support these findings.
OP57 All-Cause and Cause-Specific Mortality among Individuals with and Without Diabetes in England and Scotland
Authors: Gordon-Dseagu VLZ , Mindell J , Shelton N
Published: September 2012

Background

Although a growing body of evidence demonstrates an increase in cardiovascular disease (CVD) mortality among those with diabetes mellitus, the results related to other causes of death are less homogenous. The strength of the association between diabetes and mortality appears to differ by geographic location. The role that Body Mass Index (BMI) plays also requires further exploration. In the UK, one in 20 individuals is estimated to have diabetes. Therefore, even a small increase in mortality risk among those with diabetes, could result in a large number of deaths among those with the disease. This large general-population cohort study used data from England and Scotland to explore the associations between diabetes and risk of all-cause and cause-specific mortality, and examine the extent to which any increase was attributable to raised BMI.

Methods

Nationally-representative, cross-sectional data from 15 years of the Health Survey for England (HSE) (1994–2005) and Scottish Health Survey (SHeS) (1995, 1998 and 2003) were linked with mortality records up to the first quarter of 2011. Odds ratios (OR) and 95% confidence intervals (CI) adjusted for age-group and sex (model 1), plus smoking status (model 2) and additionally for BMI category (model 3) were estimated using logistic and multinomial logistic regression. Participants mentioning cancer at baseline were excluded from the study.

Results

Within this sample of 166,600 participants (5,131 with diabetes) there were 19,483 deaths (1,060 among those with diabetes, 18,423 without diabetes). All-cause mortality was greater among those with diabetes when adjusted for age, sex and smoking status (OR 1.52, 95% CI 1.41–1.65), with no reduction when adjusting for BMI category (OR 1.49, 1.37–1.64). Cause-specific mortality among those with diabetes was raised for CVD (model 2 OR 1.73, 1.55–1.93), cancer (1.24, 1.08–1.43) and ‘Other’ (1.77, 1.54–2.04) with a non-significant increase for respiratory diseases (1.21, CI 0.99–1.47). Additional adjustment for BMI had a minimal impact upon the excess mortality found among those with diabetes: CVD (OR 1.69, 1.49–1.93), cancer (1.24, 1.05–1.45), ‘Other’ causes (1.75, 1.49–2.07), and respiratory diseases (1.16, 0.92–1.47). Survival was also lower among those with diabetes compared with those without the disease at baseline.

Conclusion

Diabetes is associated with an excess of all-cause and cause-specific mortality from CVD, cancer, and ‘Other’ causes but probably not respiratory diseases. Increased BMI does not appear to be a mediating factor within the association between diabetes and cause-specific mortality.