Exorcising the positivist ghost in the priority-setting machine: NICE and the demise of the 'social value judgement'

The National Institute for Health and Care Excellence (NICE), the UK's primary health care priority-setting body, has traditionally described its decisions as being informed by 'social value judgements' about how resources should be allocated across society. This paper traces the intellectual history of this term and suggests that, in NICE's adoption of the idea of the 'social value judgement', we are hearing the echoes of welfare economics at a particular stage of its development, when logical positivism provided the basis for thinking about public policy choice. As such, it is argued that the term offers an overly simplistic conceptualisation of NICE's normative approach and contributes to a situation in which NICE finds itself without the necessary language fully and accurately to articulate its basis for decision-making. It is suggested that the notion of practical public reasoning, based on reflection about coherent principles of action, might provide a better characterisation of the enterprise in which NICE is, or hopes to be, engaged

Validation of a food frequency questionnaire in older South Africans

The International Society for Burns Injuries (ISBI) has published guidelines for the management of multiple or mass burns casualties, and recommends that 'each country has or should have a disaster planning system that addresses its own particular needs.' The need for a national burns disaster plan integrated with national and provincial disaster planning was discussed at the South African Burns Society Congress in 2009, but there was no real involvement in the disaster planning prior to the 2010 World Cup; the country would have been poorly prepared had there been a burns disaster during the event. This article identifies some of the lessons learnt and strategies derived from major burns disasters and burns disaster planning from other regions. Members of the South African Burns Society are undertaking an audit of burns care in South Africa to investigate the feasibility of a national burns disaster plan. This audit (which is still under way) also aims to identify weaknesses of burns care in South Africa and implement improvements where necessary

QSO Absorption Line Constraints on Intragroup High-Velocity Clouds

We show that the number statistics of moderate redshift MgII and Lyman limit absorbers may rule out the hypothesis that high velocity clouds are infalling intragroup material.Comment: 4 pages, no figures; submitted to Astrophysical Journal Letters; revised version, more general and includes more about Braun and Burton CHVC

Physical activity, change in blood pressure and predictors of mortality in older South Africans - a 2-year follow-up study

Objective. A 2-year follow-up study of a cohort of 200 historically disadvantaged older South Africans was conducted to: (i) characterise current levels of habitual physical activity; (ii) relate physical activity to current risk factors for chronic disease; and (iii) identify risk factors associated with 2-year mortaJity. The baseline sample, drawn in 1993, was found to have a high prevalence of hypertension (71.7%). Research design. Retrospective cohort study. Methods. A baseline sample of 200 persons aged ;:;.. 65 years, resident in the Cape Peninsula, was randomly drawn by means of a two-stage cluster design. Baseline measurements included: anthropometry, waist/hip ratio, systolic and diastolic blood pressure, body mass index (BMI), serum albumin, serum ferritin, haemoglobin and fasting plasma glucose levels, plasma lipid profiles, oral glucose tolerance test and self-reported health status. SUbjects were revisited after 2 years, at which time an adapted version of the Yale Physical Activity Survey was administered and measurements of blood pressure and anthropometry were repeated. Statistical analyses. Spearman\u27s rank-order correlations were used to describe relationships between various current risk factors and physical activity. Logistic regression was used to detennine predictors of 2-year mortality from baseline data. Results. At follow-up, 142 of the SUbjects (66 men, 76 women) were traced and measurements collected. Thirtytwo subjects were reported to have died by relatives liVing in the same household (22 men, 10 women). Levels of reported physical activity in the survivors were two-thirds lower than those reported in a sample of North Americans of similar age. There was an inverse association between age and physical activity (r = --{).31; P \u3c 0.0005) and a positive association between BMI and physical activity (r = 0.29; P \u3c 0.005). There was, however, no association between physical activity and systolic or diastolic blood pressure. In men, BMI in the lower tertile (P = 0.07) and serum ferritin levels were positively associated with increased mortality. Serum albumin levels were protective overthe 2-year follow-up period (OR = 0.85; P \u3c 0.05). In women, being diabetic (OR =4.88; P =0.06) and having a waistlhip ratio in the upper tertile (OR =3.26; P =0.06) were associated with mortality. Conclusions. Physical activity levels in this sample of older historically disadvantaged South Africans were habitually low. Simple anthropometric assessments incorporating weight and waistlhip ratio, together with serum albumin measurements, may be useful to screen general health risk for older adults at primary care level and provide indications for social or medical intervention. Further, strategies for earlier detection and effective management of diabetes, particularly in older women, may reduce premature mortality in this population

Physical activity, change in blood pressure and predictors of mortality in older South Africans - a 2-year follow-up study

Objective. A 2-year follow-up study of a cohort of 200 historically disadvantaged older South Africans was conducted to: (i) characterise current levels of habitualphysical activity; (ii) relate physical activity to current risk factors for chronic disease; and (iii) identify risk factors associated with 2-year mortality. The baseline sample, drawn in 1993, was found to have a high prevalence of hypertension (71.7%).Research design. Retrospective cohort study.Methods. A baseline sample of 200 persons aged ≥ 65 years, resident in the Cape Peninsula, was randomly drawn by means of a two-stage cluster design. Baseline measurements included: anthropometry, waist/hip ratio, systolic and diastolic blood pressure, body mass index (BMI), serum albumin, serum ferritin, haemoglobin and fasting plasma glucose levels, plasma lipid profiles, oral glucose tolerance test and self-reported health status. Subjects were revisited after 2 years, at which time an adapted version of the Yale Physical Activity Survey was administered and measurements of blood pressure and anthropometry were repeated.Statistical analyses. Spearman's rank-order correlations were used to describe relationships between various current risk factors and physical activity. Logistic regression was used to detennine predictors of 2-year mortality from baseline data.Results. At follow-up, 142 of the SUbjects (66 men, 76 women) were traced and measurements collected. Thirty-two subjects were reported to have died by relatives living in the same household (22 men, 10 women). Levels of reported physical activity in the survivors were two-thirds lower than those reported in a sample of North Americans of similar age. There was an inverse association between age and physical activity (r = -0.31; P < 0.0005) and a positive association between BMI and physical activity  (r = -0.29; P < 0.0005). There was, however, no association between physical activity and systolic or diastolic blood pressure. In men, BMI in the lower tertile (P = 0.07) and serum albumin levels were positively associated with increased mortality. Serum albumin levels were protective over the 2-year follow-up period (OR = 0.85; P < 0.05). In women, being diabetic (OR =4.88; P =0.06) and having a waist/hip ratio in the upper tertile (OR =3.26; P =0.06) were associated with mortality.Conclusions. Physical activity levels in this sample of older historically disadvantaged South Africans were habitually low. Simple anthropometric assessments incorporating weight and waistlhip ratio, together with serum albumin measurements, may be useful to screen general health risk for older adults at primary care level and provide indications for social or medical intervention. Further, strategies for earlier detection and effective management of diabetes, particularly in older women, may reduce premature mortality in this population

The Absorption Signatures of Dwarf Galaxies: The z=1.04 Multicloud Weak MgII Absorber toward PG 1634+706

We analyze high resolution spectra of a multi--cloud weak [defined as W_r(MgII) < 0.3 A] absorbing system along the line of sight to PG 1634+706. This system gives rise to a partial Lyman limit break and absorption in MgII, SiII, CII, SiIII, SiIV, CIV, and OVI. The lower ionization transitions arise in two kinematic subsystems with a separation of ~150 km/s. Each subsystem is resolved into several narrow components, having Doppler widths of 3-10 kms. For both subsystems, the OVI absorption arises in a separate higher ionization phase, in regions dominated by bulk motions in the range of 30-40 km/s. The two OVI absorption profiles are kinematically offset by ~50 km/s with respect to each of the two lower ionization subsystem. In the stronger subsystem, the SiIII absorption is strong with a distinctive, smooth profile shape and may partially arise in shock heated gas. Moreover, the kinematic substructure of SiIV traces that of the lower ionization MgII, but may be offset by ~3 km/s. Based upon photoionization models, constrained by the partial Lyman limit break, we infer a low metallicity of ~0.03 solar for the low ionization gas in both subsystems. The broader OVI phases have a somewhat higher metallicity, and they are consistent with photoionization; the profiles are not broad enough to imply production of OVI through collisional ionization. Various models, including outer disks, dwarf galaxies, and superwinds, are discussed to account for the phase structure, metallicity, and kinematics of this absorption system. We favor an interpretation in which the two subsystems are produced by condensed clouds far out in the opposite extremes of a multi-layer dwarf galaxy superwind

Temperature-tuning of near-infrared monodisperse quantum dot solids at 1.5 um for controllable Forster energy transfer

We present the first time-resolved cryogenic observations of Forster energy transfer in large, monodisperse lead sulphide quantum dots with ground state transitions near 1.5 um (0.83 eV), in environments from 160 K to room temperature. The observed temperature-dependent dipole-dipole transfer rate occurs in the range of (30-50 ns)^(-1), measured with our confocal single-photon counting setup at 1.5 um wavelengths. By temperature-tuning the dots, 94% efficiency of resonant energy transfer can be achieved for donor dots. The resonant transfer rates match well with proposed theoretical models

The Population of Weak Mg II Absorbers I. A Survey of 26 QSO HIRES/Keck Spectra

We present a search for "weak" MgII absorbers [those with W_r(2796) < 0.3 A in the HIRES/Keck spectra of 26 QSOs. We found 30, of which 23 are newly discovered. The spectra are 80% complete to W_r(2796) = 0.02 A and have a cumulative redshift path of ~17.2 for the redshift range 0.4 < z < 1.4. The number of absorbers per unit redshift, dN/dz, is seen to increase as the equivalent width threshold is decreased; we obtained dN/dz = 1.74+/-0.10 for our 0.02 <= W_r(2796) < 0.3 A sample. The equivalent width distribution follows a power law with slope -1.0; there is no turnover down to W_r(2796) = 0.02 A at = 0.9. Weak absorbers comprise at least 65% of the total MgII absorption population, which outnumbers Lyman limit systems (LLS) by a factor of 3.8+/-1.1; the majority of weak MgII absorbers must arise in sub-LLS environments. Tentatively, we predict that ~5% of the Lyman-alpha forest clouds with W_r(1215) > 0.1 A will have detectable MgII absorption to W_r,min(2796) = 0.02 A and that this is primarily a high-metallicity selection effect (Z/Z_sun] > -1). This implies that MgII absorbing structures figure prominently as tracers of sub-LLS environments where gas has been processed by stars. We compare the number density of W_r(2796) > 0.02 A absorbers with that of both high and low surface brightness galaxies and find a fiducial absorber size of 35h^-1 to 63h^-1 kpc, depending upon the assumed galaxy population and their absorption properties. The individual absorbing "clouds" have W_r(2796) <= 0.15 A and their narrow (often unresolved) line widths imply temperatures of ~25,000 K. We measured W_r(1548) from CIV in FOS/HST archival spectra and, based upon comparisons with FeII, found a range of ionization conditions (low, high, and multi-phase) in absorbers selected by weak MgII.Comment: Accepted Version: 43 pages, PostScript figures embedded; accepted to ApJ; updated version includes analysis of CIV absorptio