Study of Optical-Feedback Using an Integrated Laser-Modulator/Amplifier Device

We study optical-feedback effects using an integrated laser-modulator/amplifier. Our experiment and theory are agree well and provide interesting results of feedback effects on optical spectrum, spatial-hole burning, the photon density profile, and the microwave modulation

Experimental observation of trajectories beyond the long in high order harmonic generation

We experimentally observe longer than long trajectory influence in high order harmonic generation (HHG) by varying the peak intensity of the driving laser field through either direct attenuation, or by chirping the laser pulse. Using a theoretical Gaussian beam model to simulate spatial interference resulting from quantum path interference we show that the measured interference patterns cannot be solely explained by the well established short and long trajectories. The structure change is most prominent for the more divergent, off-axis components of the lower plateau harmonic region, affecting the direction and amplitude of the extreme ultraviolet light emitted, and is thus of importance for understanding and controlling the fundamentals of the HHG process.Comment: 10 pages and 8 figure

Responding to the changing burden of disease for children and adolescents in modern Britain: the RCPCH State of Child Health Report 2017

The Royal College of Paediatrics and Child Health published the State of Child Health (SOCH) 2017, summarising the changing burden of disease in UK children and young people (CYP) over the past 20 years. These data show clearly that the three great challenges of our time for CYP are obesity, mental health problems and the impact of poverty and inequality on health. In this review, we summarise key findings from SOCH 2017 and outline key responses the UK must make to improve health and well-being for its CYP

A transit timing analysis of seven RISE light curves of the exoplanet system HAT-P-3

We present seven light curves of the exoplanet system HAT-P-3, taken as part of a transit timing programme using the rapid imager to search for exoplanets instrument on the Liverpool Telescope. The light curves are analysed using a Markov chain Monte Carlo algorithm to update the parameters of the system. The inclination is found to be i= 86.75+0.22−0.21 °, the planet-star radius ratio to be Rp/R★= 0.1098+0.0010−0.0012 and the stellar radius to be R★= 0.834+0.018−0.026 R⊙, consistent with previous results but with a significant improvement in the precision. Central transit times and uncertainties for each light curve are also determined, and a residual permutation algorithm is used as an independent check on the errors. The transit times are found to be consistent with a linear ephemeris, and a new ephemeris is calculated as Tc(0) = 245 4856.701 18 ± 0.000 18 HJD and P= 2.899 738 ± 0.000 007 d. Model timing residuals are fitted to the measured timing residuals to place upper mass limits for a hypothetical perturbing planet as a function of the period ratio. These show that we have probed for planets with masses as low as 0.33 and 1.81 M⊕ in the interior and exterior 2:1 resonances, respectively, assuming the planets are initially in circular orbits

Shaping the global communications milieu : the EU's influence on internet and telecommunications governance

This article evaluates the European Union's (EU) influence in shaping the global governance for telecommunications and the Internet. Through analysing EU behaviour within an actorness framework, we demonstrate how the external opportunity structure and the EU's internal environment has impacted on its ability to exert and maximize its presence in order to meet its goals and aims in these two very different sub-sectors of global communications in terms of evolution and development. Such a comparison of EU actorness, we argue, is revealing in terms of uncovering the underlying factors and conditions that allow the EU to influence two important and dynamic communications sub-sectors

Language motivation in a reconfigured Europe: access, identity, autonomy

In this paper, I propose that we need to develop an appropriate set of conceptual tools for examining motivational issues pertaining to linguistic diversity, mobility and social integration in a rapidly changing and expanding Europe. I begin by drawing on research that has begun to reframe the concept of integrative motivation in the context of theories of self and identity. Expanding the notion of identity, I discuss the contribution of the Council of Europe's European Language Portfolio in promoting a view of motivation as the development of a plurilingual European identity and the enabling of access and mobility across a multilingual Europe. Next, I critically examine the assumption that the individual pursuit of a plurilingual identity is unproblematic, by highlighting the social context in which motivation and identity are constructed and embedded. To illuminate the role of this social context, I explore three inter-related theoretical frameworks: poststructuralist perspectives on language motivation as 'investment'; sociocultural theory; and theories of autonomy in language education. I conclude with the key message that, as with autonomy, language motivation today has an inescapably political dimension of which we need to take greater account in our research and pedagogical practice

Impact of rhinitis on asthma severity in school-age children.

BACKGROUND: In a population-based sample of school-age children, we investigated factors associated with rhinitis, and differences between allergic and nonallergic rhinitis. Amongst children with asthma, we explored the association between rhinitis and asthma severity. METHODS: Children participating in a birth cohort study (n = 906) were reviewed at age 8 years. Asthma was defined as at least two of the following three features: physician-diagnosed asthma, currently using asthma medication and current wheeze. We measured lung function (plethysmography and spirometry) and airway hyper-reactivity (AHR; methacholine challenge). RESULTS: In the analysis adjusted for the presence of asthma, children with rhinitis had significantly higher AHR (P = 0.001). Maternal smoking and absence of breastfeeding were stronger predictors of nonallergic rhinitis, whereas current wheeze and eczema were stronger predictors of allergic rhinitis. Amongst asthmatics (n = 159), when compared to 76 children without rhinitis, those with rhinitis (n = 83) were 2.89-fold (95% CI 1.41-5.91) more likely to experience frequent attacks of wheezing, 3.44-fold (1.19-9.94) more likely to experience severe attacks of wheezing limiting speech, 10.14-fold (1.27-81.21) more likely to have frequent visits to their doctor because of asthma and nine-fold (1.11-72.83) more likely to miss school. Reported use of intranasal corticosteroids resulted in a numerically small, but consistent reduction in risk, rendering the associations between rhinitis and asthma severity nonsignificant. CONCLUSION: We observed differences in risk factors and severity between allergic and nonallergic rhinitis. In children with asthma, rhinitis had adverse impact on asthma severity. The use of intranasal corticosteroids resulted in a small, but consistent reduction in the risk

Happy Moves? Assessing the Link between Life Satisfaction and Emigration Intentions

© 2015 John Wiley & Sons Ltd. It has been shown that higher levels of subjective well-being lead to greater work productivity, better physical health and enhanced social skills. Because of these positive externalities, policymakers across the world should be interested in attracting and retaining happy and life-satisfied migrants. This paper studies the link between life satisfaction and one's intentions to move abroad. Using survey data from 35 European and Central Asian countries, I find a U-shaped association between life satisfaction and emigration intentions: it is the most and the least life-satisfied people who are the most likely to express intentions to emigrate. This result is found in countries with different levels of economic development and institutional quality. The instrumental variable results suggest that higher levels of life satisfaction have a positive effect on the probability of reporting intentions to migrate. The findings of this paper raise concerns about possible 'happiness drain' in migrant-sending countries