Body mass index and airway hyper-responsiveness in individuals without respiratory disease

BACKGROUND: Overweight and obesity are major health issues in Western societies. They are related with a higher risk of different co-morbidities but their relationship with airway hyperresponsiveness (AHR) is still under discussion. Nevertheless, they are related to higher severity in asthma and other respiratory diseases. The aim of the study was to analyze the AHR in individuals with normal lung function without respiratory disorders, according to body mass index (BMI) calculation. METHODS: We performed clinical observation and basal lung function tests (LFT) in 595 consecutive individuals in order to exclude respiratory disease. 377 individuals fulfilled the criteria of normal values according international guidelines. They were submitted to standardized treadmill exercise test followed by bronchodilator test. FVC, FEV1, FEF 25/75, RV and Raw were obtained at different conditions according to BMI groups (I: lean; II: normal; III: overweight; IV obese). RESULTS: 55.2% of the sample was overweight or obese, and a signficant relationship was found with female gender and older ages (p=0.0046 and p<0.0001 respectively). The positive response to exercise test or bronchodilator beta2 agonists was not significantly frequent compared with the other groups. In obese individuals the exercise markedly reduced basal Raw and increased FEF 25/75. Lean individuals showed higher basal values of RV that was reduced upon exercise. Response to 12 agonists showed no differences according to weight biotypes. CONCLUSION: BMI hampers lung function in normal individuals, and seems not to be related to AHR. Regular exercise should be encouraged in overweight and obese individuals, since it increases their bronchial permeability as shown in lower frequency of positive exercise tests. The same is advisable for lean individuals for different reasons. Their increased basal RV and Raw improve upon exercise. Despite overweight and obesity are being related to a low-grade of basal systemic inflammation, there was no association with a higher basal bronchial hyperresponsiveness in these individuals

Nonclassical 2-photon interference with separate intrinsically narrowband fibre sources

In this paper, we demonstrate a source of photon pairs based on four-wave-mixing in photonic crystal fibres. Careful engineering of the phase matching conditions in the fibres enables us to create photon pairs at 597 nm and 860 nm in an intrinsically factorable state showing no spectral correlations. This allows for heralding one photon in a pure state and hence renders narrow band filtering obsolete. The source is narrow band, bright and achieves an overall detection efficiency of up to 21% per photon. For the first time, a Hong-Ou-Mandel interference with unfiltered photons from separate fibre sources is presented.Comment: 10 pages, 6 figure

Intrinsically narrowband pair photon generation in microstructured fibres

In this paper we study the tailoring of photon spectral properties generated by four-wave mixing in a birefringent photonic crystal fibre (PCF). The aim is to produce intrinsically narrow-band photons and hence to achieve high non-classical interference visibility and generate high fidelity entanglement without any requirement for spectral filtering, leading to high effective detection efficiencies. We show unfiltered Hong-Ou-Mandel interference visibilities of 77% between photons from the same PCF, and 80% between separate sources. We compare results from modelling the PCF to these experiments and analyse photon purities.Comment: 23 pages, 17 figures, Comments Welcom

Near-threshold high spin amplification in a 1300 nm GaInNAs spin laser

Using continuous-wave optical pumping of a spin-VCSEL at room temperature, we find high spin amplification of the pump close to threshold within the communications wavelength window, here at 1300 nm. This facilitates a strong switch from left to right circularly polarised light emission, which has potential applications in polarisation encoding for data communications. We use a simple spin flip model to fit the experimental results and discuss the VCSEL parameters that affect this amplification

Ripples in a pond: Do social work students need to learn about terrorism?

In the face of heightened awareness of terrorism, however it is defined, the challenges for social work are legion. Social work roles may include working with the military to ensure the well-being of service-men and women and their families when bereaved or injured, as well as being prepared to support the public within the emergency context of an overt act of terrorism. This paper reviews some of the literature concerning how social work responds to confl ict and terrorism before reporting a smallscale qualitative study examining the views of social work students, on a qualifying programme in the UK, of terrorism and the need for knowledge and understanding as part of their education

‘Everyday bordering’ in England, Sweden and Bulgaria: Social work decision-making processes when working with migrant family members

The global movement of people is a growing feature of contemporary life, and it is essential that professionals providing support services know how to best engage with migrant families. However, despite globalisation and the related processes of de-bordering, borders continue to remain significant and, in contemporary life, the ways in which immigration is controlled and surveilled—bureaucratically and symbolically—are multiple. The paper draws on data gathered in the immediate period following the so called 2015 European ‘migration crisis’ and examines whether and in what ways social workers in three European countries—Bulgaria, Sweden and England—enact bordering in their work with migrant family members. We apply the concept of ‘everyday bordering’ to the data set: whilst borders are traditionally physical and at the boundary between nation states, bordering practices increasingly permeate everyday life in bureaucratic and symbolic forms. Overall, the data show that everyday bordering affects social work practice in three ways: by social workers being required to engage in bordering as an everyday practice; by producing conditions that require social workers to negotiate borders; and in revealing aspects of symbolic everyday bordering. Our analyses shows that ‘everyday bordering’ practices are present in social work decision-making processes in each country, but the forms they take vary across contexts. Analysis also indicates that, in each country, social workers recognise the ways in which immigration control can impact on the families with whom they work but that they can also inadvertently contribute to the ‘othering’ of migrant populations