Validity of self-reported smoking status: comparison of patients admitted to hospital with acute coronary syndrome and the general population

Many studies rely on self-reported smoking status. We hypothesized that patients with acute coronary syndrome (ACS), a smoking-related condition, would be more prone to misclassify themselves as ex-smokers, because of pressure to quit. We compared patients admitted with ACS with a general population survey conducted in the same country at a similar time. We determined whether ACS patients who classified themselves as ex-smokers (n = 635) were more likely to have cotinine levels suggestive of smoking deception than self-reported ex-smokers in the general population (n = 289). On univariate analysis, the percentage of smoking deceivers was similar among ACS patients and the general population (11% vs. 12%, p = .530). Following adjustment for age, sex and exposure to environmental tobacco smoke, ACS patients were significantly more likely to misclassify themselves (adjusted OR = 14.06, 95% CI 2.13-93.01, p = .006). There was an interaction with age whereby the probability of misclassification fell significantly with increasing age in the ACS group (adjusted OR = 0.95, 95% CI 0.93-0.97, p<.001), but not in the general population. Overall, smoking deception was more common among ACS patients than the general population. Studies comparing patients with cardiovascular disease and healthy individuals risk introducing bias if they rely solely on self-reported smoking status. Biochemical confirmation should be undertaken in such studies

Nature, change and agency in Aristotle's Physics

The concept of "nature as inner principle of change" is fundamental to Aristotle's theory of the physical world; it is the object of the present thesis to substantiate this claim by tracing the effects of this idea in Aristotle's rejection of materialism, in his doctrine of "natural places", in his definition of change and process in general, and (via the latter) in his notion of agency in general and the supreme Unmoved Mover in particular ((1)). Aristotle elucidates "natural" by . contrast with "artificial" ((2) - (3)), holding that natural substances not merely collectively ((4) - (5)) but as individuals each possess an 'innate impulse of change'. But this must be explained so as to allow for the fact that no change is entirely independent of external conditions ((6) - (7)). If, however, change were totally dependent on external conditions, its occurrence would be inexplicable ((8) - (9)), and the very concept of "change" would be incoherent. This latter conclusion emerges from an examination of the ancient paradox of becoming and Aristotle's treatment of it ((10) - (33)). The paradox is expounded ((11) -(14)). Aristotle answers it by showing that language assumes a continuing subject of change ((15) - (21)). But this assumption meets the problem only if the metaphysical category of substance is also assumed, and along with it some distinction between substance-constitutive and non-substance-constitutive characteristics ((22) - (27)). The former mark off their subject as a thing of a certain causal type; thus change, in presupposing a substantial subject (see also Appendix to Chapter 1), presupposes one that makes some causal contribution to its own changes ((28) - (33)). But Aristotle means more than this by 'nature as inner principle'. He holds a natural substance to be (like a craftsman) the autonomous determinant of certain changes; these therefore (by contrast with changes not so determined) are "natural", as manifesting the substantial nature ((34) - (36)). This problematic notion is taken for granted by Aristotle in the Vhys-ics ((37) - (39)), but can be seen to rest on his metaphysic of substance. It is a consequence of this that the natural change of a given substance be of one kind and display a unitary pattern reflecting the unity of the substance ((40)). This view cripples scientific method as we understand it ((41)), but Aristotle's idea of substance anyway cuts him off from the approaches successfully operated in later mechanics and chemistry ((42) - (45)). A summary of the ground so far covered ((46)) introduces a further sense in which Aristotle's natures are "inner" principles of change: the subject of change is not (as in artifice) external to the being which is the source of change ((47) - (54))

What Does Aristotle\u27s Prime Mover Do?

The Prime Mover of Metaphysics Lambda is the source, above all, of eternal motion in the first sphere. It may seem silly to ask \u27What (according to Lambda) does the Prime Mover do?\u27 The answer is obvious: \u27He — or it — gives rise to the motion of the first sphere\u27. But according to a widely accepted interpretation, this is not what the Prime Mover does first and foremost; instead, the Mover essentially contemplates. This contemplative conception is my target here. I shall adduce reasons for suspecting that the contemplative Prime Mover is not an Aristotelian postulate in Lambda, but an exegetical construct. I shall simultaneously make a case for holding that the actual Prime Mover in Lambda should be viewed as a kinetic agent (which is how the Prime Mover is generally presented elsewhere in the corpus). These arguments are founded on conceptual as well as textual considerations, and on reasonable assumptions concerning Aristotle\u27s aims in Lambda and his capacity for self-criticism especially in respect of absurdities for which he castigates other philosophers. I shall not, however, rely on debatable hypotheses about the development of his theology through several treatises, or about his journey towards or away from Platonism. I shall be concerned with the Prime Mover only in Metaphysics Lambda, and within Lambda I shall restrict the discussion to relations that may be thought to obtain between the Prime Mover, the first sphere, and the movement of that sphere. And as well as saying almost nothing about the other spheres and their movers, I shall touch only briefly on the celebrated doctrine in Ch. 9 that the Prime Mover\u27s activity is a thinking of thinking

“Forum: Humour”

An intellectual roundtable published by Oxford University Press on behalf of German History Society, with colleagues Profs. Peter Burke (Cambridge University, England), Martina Kessel (University of Bielefeld, Germany), Joanathan Waterlow Oxford University, England)

Mathematical Modelling of Cross-protection Between Respiratory Viruses.

Respiratory viruses cause substantial health and economic burdens. These viruses circulate concurrently, and changes in host susceptibility brought about by infection by one virus has the potential to change the transmission dynamics of another. Understanding the effects of such cross-protection between viruses at a population level can inform public health policies. Current evidence for cross-protection between these viruses mainly comes from population level shifts in dynamics, which cannot assess causation, and from small-scale biological experiments. I use mathematical modelling to research cross-protection between respiratory viruses, as these methods allow for testing of the mechanism. Initially, I develop a two-pathogen interaction model parameterised to simulate influenza and RSV epidemiology in the UK. Using a surveillance-like stochastic observation process I generate a range of possible trajectories, and then back-infer the parameters using Markov Chain Monte Carlo. I found that the strength and duration of influenza and RSV interaction could be estimated well; however, the robustness of inference does decline towards the extremes of the plausible parameter ranges, with misleading results. Next, I use parallel tempering to fit an adapted two-pathogen model to a unique dataset from Vietnam. I show that the population level-dynamics of influenza and RSV circulation support either moderate or no cross-protection. However, I add evidence that co-infection increases the rate of reporting. The benefits of limiting severe co-infection by vaccination in this setting may therefore outweigh the increased transmission that occurs due to cross-protection between the viruses. Finally, I use coronavirus surveillance data from England and Wales to estimate key seasonal coronavirus (HCoV) parameters, and I use these estimates to investigate age-specific susceptibility to SARS-CoV-2, varying the interaction assumption. I show that while cross-protection between HCoV and SARS-CoV-2 may contribute to the age distribution, it is insufficient to explain the observed reduced susceptibility of children. Collectively, the research in this thesis demonstrates that surveillance data and mathematical models can be used to study respiratory viral interactions. It implies that while models can be used to study this phenomenon, stochasticity can obscure results. The research also alleviates concerns that vaccination against influenza or RSV may have a detrimental impact on the other virus, due to interaction, although this must be investigated further to understand the generalisability of the results to other settings. Finally, the research implies that other factors must influence susceptibility to coronaviruses, and the observed shifting of epidemic peaks that has been hypothesised to be a result of respiratory viral interaction

Wound care in older adults

Wound care in older adults is complex. A logical, structured approach should be taken, using a nursing process such as assessing, planning, implementing and evaluating. This clinical focus paper outlines the nursing process to support wound care in this patient group. It recommends considering dressing selection as a cost-effective, prescribing decision because of the risks and comorbidities associated with these patient

An isotope dilution model for partitioning of phenylalanine and tyrosine uptake by the liver of lactating dairy cows

An isotope dilution model to describe the partitioning of phenylalanine (PHE) and tyrosine (TYR) in the bovine liver was developed. The model comprises four intracellular and six extracellular pools and various flows connecting these pools and external blood. Conservation of mass principles were applied to generate the fundamental equations describing the behaviour of the system in the steady state. The model was applied to datasets from multi-catheterised dairy cattle during a constant infusion of [1-13C] phenylalanine and [2,3,5,6-2H] tyrosine tracers. Model solutions described the extraction of PHE and TYR from the liver via the portal vein and hepatic artery. In addition, the exchange of free PHE and TYR between extracellular and intracellular pools was explained and the hydroxylation of PHE to TYR was estimated. The model was effective in providing information about the fates of PHE and TYR in the liver and could be used as part of a more complex system describing amino acid metabolism in the whole animal

The effect of acidosis on the labelling of urinary ammonia during infusion of [amide-15N]glutamine in human subjects

In three experiments [amide-15N]glutamine was infused intravenously in male volunteers. After 4-8 h of infusion acidosis was achieved by an oral dose of CaCl2 (1 mmol/kg). In one subject acidosis was maintained for 5 d. The acid load produced an approximately 3-fold increase in urinary NH3 excretion, with a small (approximately 20%) and transient increase in the isotope abundance of urinary NH3 Estimates of glutamine production rate (flux) were obtained in two experiments. There was no evidence that it was increased in acidosis. The extra NH3 production by the kidney represented only a very small part, about 3%, of the total glutamine production rat

Trust and transparency in times of crisis: Results from an online survey during the first wave (April 2020) of the COVID-19 epidemic in the UK

BACKGROUND: The success of a government's COVID-19 control strategy relies on public trust and broad acceptance of response measures. We investigated public perceptions of the UK government's COVID-19 response, focusing on the relationship between trust and perceived transparency, during the first wave (April 2020) of the COVID-19 pandemic in the United Kingdom. METHODS: Anonymous survey data were collected (2020-04-06 to 2020-04-22) from 9,322 respondents, aged 20+ using an online questionnaire shared primarily through Facebook. We took an embedded-mixed-methods approach to data analysis. Missing data were imputed via multiple imputation. Binomial & multinomial logistic regression were used to detect associations between demographic characteristics and perceptions or opinions of the UK government's response to COVID-19. Structural topic modelling (STM), qualitative thematic coding of sub-sets of responses were then used to perform a thematic analysis of topics that were of interest to key demographic groups. RESULTS: Most respondents (95.1%) supported government enforcement of behaviour change. While 52.1% of respondents thought the government was making good decisions, differences were apparent across demographic groups, for example respondents from Scotland had lower odds of responding positively than respondents in London. Higher educational levels saw decreasing odds of having a positive opinion of the government response and decreasing household income associated with decreasing positive opinion. Of respondents who thought the government was not making good decisions 60% believed the economy was being prioritised over people and their health. Positive views on government decision-making were associated with positive views on government transparency about the COVID-19 response. Qualitative analysis about perceptions of government transparency highlighted five key themes: (1) the justification of opacity due to the condition of crisis, (2) generalised mistrust of politics, (3) concerns about the role of scientific evidence, (4) quality of government communication and (5) questions about political decision-making processes. CONCLUSION: Our study suggests that trust is not homogenous across communities, and that generalised mistrust, concerns about the transparent use and communication of evidence and insights into decision-making processes can affect perceptions of the government's pandemic response. We recommend targeted community engagement, tailored to the experiences of different groups and a new focus on accountability and openness around how decisions are made in the response to the UK COVID-19 pandemic

Splanchnic metabolism of nutrients and hormones in steers fed alfalfa under conditions of increased absorption of ammonia and L-arginine supply across the portal-drained viscera

Effects of increased ammonia and/or arginine absorption on net splanchnic (portal-drained viscera [PDV] plus liver) metabolism of nonnitrogenous nutrients and hormones in cattle were examined. Six Hereford × Angus steers (501 ± 1 kg BW) prepared with vascular catheters for measurements of net flux across the splanchnic bed were fed a 75% alfalfa:25% (as-fed basis) corn and soybean meal diet (0.523 MJ of ME/[kg BW0.75.d]) every 2 h without (27.0 g of N/kg of DM) and with 20 g of urea/kg of DM (35.7 g of N/kg of DM) in a split-plot design. Net flux measurements were made immediately before and after a 72-h mesenteric vein infusion of L-arginine (15 mmol/h). There were no treatment effects onPDVor hepaticO2 consumption. Dietary urea had no effect on splanchnic metabolism of glucose or L-lactate, but arginine infusion decreased net hepatic removal of L-lactate when urea was fed (P < 0.01). Net PDV appearance of n-butyrate was increased by arginine infusion (P < 0.07), and both dietary urea (P < 0.09) and arginine infusion (P < 0.05) increased net hepatic removal of n-butyrate. Dietary urea also increased total splanchnic acetate output (P < 0.06), tended to increase arterial glucagon concentration (P < 0.11), and decreased arterial ST concentration (P < 0.03). Arginine infusion increased arterial concentration (P < 0.07) and net PDV release (P < 0.10) and tended to increase hepatic removal (P < 0.11) of insulin, as well as arterial concentration (P < 0.01) and total splanchnic output (P < 0.01) of glucagon. Despite changes in splanchnic N metabolism, increased ammonia and arginine absorption had little measurable effect on splanchnic metabolism of glucose and other nonnitrogenous components of splanchnic energy metabolism