Spectral asymptotics and metastability for the linear relaxation Boltzmann equation

We consider the linear relaxation Boltzmann equation in a semiclassical framework. We construct a family of sharp quasimodes for the associated operator which yields sharp spectral asymptotics for its small spectrum in the low temperature regime. We deduce some information on the long time behavior of the solutions with a sharp estimate on the return to equilibrium as well as a quantitative metastability result. The main novelty is that the collision operator is a pseudo-differential operator in the critical class S^1/2 and that its action on the gaussian quasimodes yields a superposition of exponentials.Comment: arXiv admin note: text overlap with arXiv:2206.0449

Spectral analysis of a semiclassical random walk associated to a general confining potential

We consider a semiclassical random walk with respect to a probability measure associated to a potential with a finite number of critical points. We recover the spectral results from [1] on the corresponding operator in a more general setting and with improved accuracy. In particular we do not make any assumption on the distribution of the critical points of the potential, in the spirit of [15]. Our approach consists in adapting the ideas from [15] to the recent gaussian quasimodes framework which appears to be more robust than the usual methods, especially when dealing with non local operators

Political trajectories in the painting of P. Wyndham Lewis

This thesis presents an analysis of the political dimension to the paintings of Percy Wyndham Lewis (1882-1957).Through an exegesis of the discreet and latent "voices" in Lewis's paintings the ideological parameters of his thought world are disclosed. These imperatives are examined for their display of political predispositions, for values and attitudes, which reveal a loading towards specific socio-cultural standards. In so far as these standards can be identified with historically relevant political programmes they become manifestos for political actions. Or, at the very least, they can be seen to exist as critical and prescriptive social insights. Importantly, the focus of this examination and interpretation remains the visual image and its related texts. A key aspect of both the methodology and argument within this thesis, insists that the visual image is the bearer of meaning in both its subject matter and technique. Values are communicated not only in reference to the thing displayed, but, in the manner of the display. Hence, an analysis of the intellectual and formal strategies employed by Lewis in his painting becomes a central concern of the thesis. Finally, the thesis rounds on the actual nature of Lewis's politics as revealed in his approach to art. While it is accepted that the mediation from the political to the painted throws up many and substantial barriers, the thesis insists that a political reading of Lewis's creative work is not only appropriate but necessary. In offering just such a reading the author hopes to transcend the boundaries between the disciplines of Art History and Sociology

Cost-Offsets of New Medications for Treatment of Schizophrenia

Broad claims are frequently made that new medications will offset all or part of their costs by reducing other areas of Medicaid spending. In this paper we examine the net impact on spending for new drugs used to treat schizophrenia. We extend research in this area by taking a new approach to identification of spending impacts of new drugs. We specify and estimate models of spending on treatment of schizophrenia using 7 years of Florida Medicaid data. The estimates indicate that use of the new drugs result in net spending increases. This may be due to increased adherence to treatment.

PROJECTING THE IMPACT OF DEMOGRAPHIC CHANGE ON THE DEMAND FOR AND DELIVERY OF HEALTH CARE IN IRELAND. RESEARCH SERIES NUMBER 13 OCTOBER 2009

Primary care is often the first point of contact with the health care system for people requiring care. Primary care is often thought synonymous with general practitioners, but actually encompasses a large range of different professionals and services including nurses/midwives; physiotherapists; occupational therapists; dentists; opticians; chiropodists; psychologists and pharmacists. The list is not exhaustive, but still gives an indication of the wide range of services that can be grouped under the general heading of primary care. Nonetheless, GPs do have a core part to play in primary care as well as performing the role of ‘gate keeper’ to other health services such as accident and emergency or outpatient care in hospitals. The balance of treatment and referral between general practice and secondary care is, therefore, a very important issue and it has been argued that the under development of primary care services in Ireland in recent decades has contributed, and indeed, may be the most important reason, for the over-crowding of accident and emergency services and long waiting lists for elective procedures in Irish health care (Layte et al., 2007b; Tussing and Wren, 2006)

Applying a typology of health worker migration to non-EU migrant doctors in Ireland

Abstract Background: Research on health worker migration in the Irish context has categorized migrant health workers by country or region of training (for example, non-EU nurses or doctors) or recruitment mechanism (for example, actively recruited nurses). This paper applies a new typology of health worker migrants – livelihood, career-oriented, backpacker, commuter, undocumented and returner migrants (European Observatory on Health Systems and Policies and WHO, vol. 2:129-152, 2014) – to the experiences of non-EU migrant doctors in Ireland and tests its utility for understanding health worker migration internationally. Methods: The paper draws on quantitative survey (N = 366) and qualitative interview (N = 37) data collected from non-EU migrant doctors in Ireland between 2011 and 2013. Results: Categorizing non-EU migrant doctors in Ireland according to the typology (European Observatory on Health Systems and Policies and WHO, vol. 2:129-152, 2014) offers insight into their differing motivations, particularly on arrival. Findings suggest that the career-oriented migrant is the most common type of doctor among non-EU migrant doctor respondents, accounting for 60 % (N = 220) of quantitative and 54 % (N = 20) of qualitative respondents. The authors propose a modification to the typology via the addition of two additional categories – the family migrant and the safety and security migrant. Conclusions: Employing a typology of health worker migration can facilitate a more comprehensive understanding of the migrant medical workforce, a necessary prerequisite for the development of useful policy tools (European Observatory on Health Systems and Policies and WHO, vol. 2:129-152, 2014). The findings indicate that there is some fluidity between categories, as health worker motivations change over time. This indicates the potential for policy levers to influence migrant health worker decision-making, if they are sufficiently “tuned in” to migrant health worker motivation. Keywords: Doctor migration, Migration typology, Medical workforce planning, Health workforce planning, Health human resources for healt

Nanosecond Electric Pulses Differentially Affect Inward and Outward Currents in Patch Clamped Adrenal Chromaffin Cells

This study examined the effect of 5 ns electric pulses on macroscopic ionic currents in whole-cell voltage-clamped adrenal chromaffin cells. Current-voltage (I-V) relationships first established that the early peak inward current was primarily composed of a fast voltage-dependent Na+ current (INa), whereas the late outward current was composed of at least three ionic currents: a voltage-gated Ca2+ current (ICa), a Ca2+-activated K+ current (IK(Ca)), and a sustained voltage-dependent delayed rectifier K+ current (IKV). A constant-voltage step protocol was next used to monitor peak inward and late outward currents before and after cell exposure to a 5 ns pulse. A single pulse applied at an electric (E)-field amplitude of 5 MV/m resulted in an instantaneous decrease of ~4% in peak INa that then declined exponentially to a level that was ~85% of the initial level after 10 min. Increasing the E-field amplitude to 8 or 10 MV/m caused a twofold greater inhibitory effect on peak INa. The decrease in INa was not due to a change in either the steady-state inactivation or activation of the Na+ channel but instead was associated with a decrease in maximal Na+ conductance. Late outward current was not affected by a pulse applied at 5 MV/m. However, for a pulse applied at the higher E-field amplitudes of 8 and 10 MV/m, late outward current in some cells underwent a progressive ~22% decline over the course of the first 20 s following pulse exposure, with no further decline. The effect was most likely concentrated on ICa and IK(Ca) as IKV was not affected. The results of this study indicate that in whole-cell patch clamped adrenal chromaffin cells, a 5 ns pulse differentially inhibits specific voltage-gated ionic currents in a manner that can be manipulated by tuning E-field amplitude

2-ns Electrostimulation of Ca\u3csup\u3e2+\u3c/sup\u3e Influx Into Chromaffin Cells: Rapid Modulation by Field Reversal

Cellular effects of nanosecond pulsed electric field exposures can be attenuated by an electric field reversal, a phenomenon called bipolar pulse cancellation. Our investigations of this phenomenon in neuroendocrine adrenal chromaffin cells show that a single 2 ns, 16 MV/m unipolar pulse elicited a rapid, transient rise in intracellular Ca2+ levels due to Ca2+ influx through voltage-gated calcium channels. The response was eliminated by a 2 ns bipolar pulse with positive and negative phases of equal duration and amplitude, and fully restored (unipolar-equivalent response) when the delay between each phase of the bipolar pulse was 30 ns. Longer interphase intervals evoked Ca2+ responses that were greater in magnitude than those evoked by a unipolar pulse (stimulation). Cancellation was also observed when the amplitude of the second (negative) phase of the bipolar pulse was half that of the first (positive) phase but progressively lost as the amplitude of the second phase was incrementally increased above that of the first phase. When the amplitude of the second phase was twice that of the first phase, there was stimulation. By comparing the experimental results for each manipulation of the bipolar pulse waveform with analytical calculations of capacitive membrane charging/discharging, also known as accelerated membrane discharge mechanism, we show that the transition from cancellation to unipolar-equivalent stimulation broadly agrees with this model. Taken as a whole, our results demonstrate that electrostimulation of adrenal chromaffin cells with ultrashort pulses can be modulated with interphase intervals of tens of nanoseconds, a prediction of the accelerated membrane discharge mechanism not previously observed in other bipolar pulse cancellation studies. Such modulation of Ca2+ responses in a neural-type cell is promising for the potential use of nanosecond bipolar pulse technologies for remote electrostimulation applications for neuromodulation