Economic Stress and the Great Recession in Ireland: Polarization, Individualization or ‘Middle Class Squeeze’?

Following an unprecedented boom, since 2008 Ireland has experienced a severe economic crisis. Considerable debate persists as to where the heaviest burden of the recession has fallen. Conventional measures of income poverty and inequality have a limited capacity to answer this question. Our analysis, which focuses on economic stress and the mediating role of material deprivation, provides no evidence for individualization or class polarization. Instead we find that while economic stress level are highly stratified in income class and social class terms in both boom and bust periods, the changing impact of class is contingent on life course stage. The affluent income class remained largely insulated from the experience of economic stress. However, it saw its relative advantage overthe income poor class decline at the earlier stage of the life-course. At the other end of the hierarchy, the income poor experienced a relative improvement in their situation in the early life course phases. The precarious income class experienced some improvement in its situation at the earlier life course stages while the outcomes for the middle classes remain unchanged. In the mid-life course stages the precarious and lower middle classes experienced disproportionate increase in their stress levels while at the later life-cycle stage it is the combined middle classes that lost out. Additional effects over time relating to social class are restricted to the deteriorating situation of the petit bourgeoisie at the middle stage of the life-course. The pattern is clearly a good deal more complex that suggested by conventional notions of ‘middle class squeeze’ and points to the distinctive challenges relating to welfare and taxation policy faced by governments in the Great Recession.

Polarization-dependent one-way surface wave propagation

We numerically study nonreciprocal regimes of surface plasmon-polariton at the interface between two gyrotropic media. We predict existence of isolated unidirectional TE and TM surface modes guided by the interface between gyroelectric and gyromagnetic media.

Relativistic breather-type solitary waves with linear polarization in cold plasmas

Linearly polarized solitary waves, arising from the interaction of an intense laser pulse with a plasma, are investigated. Localized structures, in the form of exact numerical nonlinear solutions of the one-dimensional Maxwell-fluid model for a cold plasma with fixed ions, are presented. Unlike stationary circularly polarized solitary waves, the linear polarization gives rise to a breather-type behavior and a periodic exchange of electromagnetic energy and electron kinetic energy at twice the frequency of the wave. A numerical method based on a finite-differences scheme allows us to compute a branch of solutions within the frequency range Ωmin<Ω<ωpe, where ωpe and Ωmin are the electron plasma frequency and the frequency value for which the plasma density vanishes locally, respectively. A detailed description of the spatiotemporal structure of the waves and their main properties as a function of Ω is presented. Small-amplitude oscillations appearing in the tail of the solitary waves, a consequence of the linear polarization and harmonic excitation, are explained with the aid of the Akhiezer-Polovin system. Direct numerical simulations of the Maxwell-fluid model show that these solitary waves propagate without change for a long time.

Evidence of plasma polarization shift of Ti He-alpha resonance line in high density laser produced plasmas

A spectroscopic study of the He-alpha (1s(2) S-1(0) - 1s2p P-1(1)) line emission (4749.73 eV) from high density plasma was conducted. The plasma was produced by irradiating Ti targets with intense (I approximate to 1x10(19) W/cm(2)), 400nm wavelength high contrast, short (45fs) p-polarized laser pulses at an angle of 45 degrees. A line shift up to 3.4 +/- 1.0 eV (1.9 +/- 0.55 m angstrom) was observed in the He-alpha line. The line width of the resonance line at FWHM was measured to be 12.1 +/- 0.6 eV (6.7 +/- 0.35 m angstrom). For comparison, we looked into the emission of the same spectral line from plasma produced by irradiating the same target with laser pulses of reduced intensities (approximate to 10(17) W/cm(2)): we observed a spectral shift of only 1.8 +/- 1.0 eV (0.9 +/- 0.55m angstrom) and the line-width measures up to 5.8 +/- 0.25 eV (2.7 +/- 0.35 m angstrom). These data provide evidence of plasma polarization shift of the Ti He-alpha line.

X-ray Polarization Measurements of Dense Plasmas Heated by Fast Electrons

The detailed knowledge of fast electron energy transport following interaction with high-intensity, ultra-short laser pulses is a key area for secondary source generation for ELI. We demonstrate polarization spectroscopy at laser intensities up to 10(21) Wcm(-2). This is significant as it suggests that in situ emission spectroscopy may be used as an effective probe of fast electron velocity distributions in regimes relevant to electron transport in solid targets. Ly-alpha doublet emission of nickel (Z = 28) and sulphur (Z = 16) is observed to measure the degree of polarization from the Ly-alpha(1) emission. Ly-alpha(2) emission is unpolarized, and as such acts as a calibration source between spectrometers. The measured ratio of the X-ray sigma- and pi-polarization allows the possibility to infer the velocity distribution function of the fast electron beam.

X-ray Polarization Spectroscopy from Ultra-Intense Interactions

Detailed knowledge of fast electron energy transport following the interaction of ultrashort intense laser pulses is a key subject for fast ignition. This is a problem relevant to many areas of laser-plasma physics with particular importance to fast ignition and X-ray secondary source development, necessary for the development of large-scale facilities such as HiPER and ELI. Operating two orthogonal crystal spectrometers set at Bragg angles close to 45 degrees determines the X-ray s- and p-polarization ratio. From this ratio, it is possible to infer the velocity distribution function of the fast electron beam within the dense plasma. We report on results of polarization measurements at high density for sulphur and nickel buried layer targets in the high intensity range of 10(19) - 10(21) Wcm(-2). We observe at 45 degrees the Ly-alpha doublet using two sets of orthogonal highly-orientated pyrolytic graphite (HOPG) crystals set in 1(st) order for sulphur and 3(rd) order for nickel.

Higher effort-reward imbalance and lower job control predict exit from the labour market at the age of 61 years or younger: Evidence from the English Longitudinal Study of Ageing

Background: We examined whether higher effort-reward imbalance (ERI) and lower job control are associated with exit from the labour market. 

Methods: There were 1263 participants aged 50-74 years from the English Longitudinal Study on Ageing with data on working status and work-related psychosocial factors at baseline (wave 2; 2004-2005), and working status at follow-up (wave 5; 2010-2011). Psychosocial factors at work were assessed using a short validated version of ERI and job control. An allostatic load index was formed using 13 biological parameters. Depressive symptoms were measured using the Center for Epidemiologic Studies Depression Scale. Exit from the labour market was defined as not working in the labour market when 61 years old or younger in 2010-2011. 

Results: Higher ERI OR=1.62 (95% CI 1.01 to 2.61, p=0.048) predicted exit from the labour market independent of age, sex, education, occupational class, allostatic load and depression. Job control OR=0.60 (95% CI 0.42 to 0.85, p=0.004) was associated with exit from the labour market independent of age, sex, education, occupation and depression. The association of higher effort OR=1.32 (95% CI 1.01 to 1.73, p=0.045) with exit from the labour market was independent of age, sex and depression but attenuated to non-significance when additionally controlling for socioeconomic measures. Reward was not related to exit from the labour market. 

Conclusions: Stressful work conditions can be a risk for exiting the labour market before the age of 61 years. Neither socioeconomic position nor allostatic load and depressive symptoms seem to explain this association.

The validity of critical thinking tests for predicting degree performance: A longitudinal study

This study explored the validity of using critical thinking tests to predict final psychology degree marks over and above that already predicted by traditional admission exams (A-levels). Participants were a longitudinal sample of 109 psychology students from a university in the United Kingdom. The outcome measures were: total degree marks; and end of year marks. The predictor measures were: university admission exam results (A-levels); critical thinking test scores (skills & dispositions); and non-verbal intelligence scores. Hierarchical regressions showed A-levels significantly predicted 10% of the final degree score and the 11-item measure of ‘Inference skills’ from the California Critical Thinking Skills Test significantly predicted an additional 6% of degree outcome variance. The findings from this study should inform decisions about the precise measurement constructs included in aptitude tests used in the higher education admission process.

Polarization spectral synthesis for Type Ia supernova explosion models

We present a Monte Carlo radiative transfer technique for calculating synthetic spectropolarimetry for multidimensional supernova explosion models. The approach utilizes 'virtual-packets' that are generated during the propagation of the Monte Carlo quanta and used to compute synthetic observables for specific observer orientations. Compared to extracting synthetic observables by direct binning of emergent Monte Carlo quanta, this virtual-packet approach leads to a substantial reduction in the Monte Carlo noise. This is not only vital for calculating synthetic spectropolarimetry (since the degree of polarization is typically very small) but also useful for calculations of light curves and spectra. We first validate our approach via application of an idealized test code to simple geometries. We then describe its implementation in the Monte Carlo radiative transfer code ARTIS and present test calculations for simple models for Type Ia supernovae. Specifically, we use the well-known one-dimensional W7 model to verify that our scheme can accurately recover zero polarization from a spherical model, and to demonstrate the reduction in Monte Carlo noise compared to a simple packet-binning approach. To investigate the impact of aspherical ejecta on the polarization spectra, we then use ARTIS to calculate synthetic observables for prolate and oblate ellipsoidal models with Type Ia supernova compositions.

Linear-to-Circular Polarization Reflector With Transmission Band

A new class of polarizing surface is proposed that in a given frequency band can reflect incident linearly polarized waves with circular polarization (CP) while at other frequencies is transparent allowing incident waves to transmit unaffected. The proposed structure consists of two parallel anisotropic frequency selective surfaces (FSSs) that independently interact with TE or TM waves, respectively. The FSSs are designed to, respectively, transmit TE and TM waves within the same transmission frequency range, so that the combined structure is transparent to all polarizations in this band. Likewise, the two arrays are designed to, respectively, reflect TE and TM incident waves in a common reflection band, so that all polarizations are fully reflected in this range; if the separation of the two arrays is such that the TE and TM components of an incident wave polarized at slant 45° experience a 90° phase shift, reflection will occur in CP. The concept and performance limitations are theoretically investigated using transmission line theory as well as full wave results. The predicted performance is validated by means of experimental results on a fabricated prototype. The proposed structure is pertinent for employment as a quasi-optical diplexer in CP dual-band systems such as reflector antennas.

The Meaning of Drug Use among Homeless Young People:A longitudinal pathways analysis

A strong link between drug use and homelessness has long since been documented in the international literature. However, much of the research has concentrated on the direction of the relationship between drug use and homelessness, seeking to establish drug use as a cause or consequence of homelessness, with far less attention to the intersection of drug and homeless ‘careers’. This paper examines the drug and homeless pathways of young people who are participants in a qualitative longitudinal study of homeless youth in Dublin, Ireland. The findings highlight downward drug transitions as associated with exiting homelessness and continued or escalated consumption as associated with remaining homeless. Analyses of the meanings young people attach to drug use over time reveal the importance of housing as an enabler to engaging with treatment and as assisting the process of becoming and remaining drug free. Young people who remained homeless did not accept their situations, as ‘acculturation’ accounts would suggest; rather, they aspired to changing their situations. However, they also face strong barriers to accessing housing which in turn hamper their efforts to address the matter of their drug use. The implications for how the homeless/drug use ‘nexus’ is conceptualised and understood, as well as implications for policy, are discussed.