Weak lensing and dark energy: the impact of dark energy on nonlinear dark matter clustering

We examine the influence of percent-level dark energy corrections to the nonlinear matter power spectrum on constraints of the dark energy equation of state from future weak lensing probes. We explicitly show that a poor approximation (off by > 10%) to the nonlinear corrections causes a > 1 sigma bias on the determination of the dark energy equation of state. Future weak lensing surveys must therefore incorporate dark energy modifications to the nonlinear matter power spectrum accurate to the percent-level, to avoid introducing significant bias in their measurements. For the WMAP5 cosmology, the more accurate power spectrum is more sensitive to dark energy properties, resulting in a factor of two improvement in dark energy equation of state constraints. We explore the complementary constraints on dark energy from future weak lensing and supernova surveys. A space-based, JDEM-like survey measures the equation of state in five independent redshift bins to ~10%, while this improves to ~5% for a wide-field ground-based survey like LSST. These constraints are contingent upon our ability to control weak lensing systematic uncertainties to the sub-percent level.Comment: 12 pages, 12 figures. Typo in Eqn 8 correcte

Implications of a transition in the dark energy equation of state for the H0H_0 and σ8\sigma_8 tensions

We explore the implications of a rapid appearance of dark energy between the redshifts ($z$) of one and two on the expansion rate and growth of perturbations. Using both Gaussian process regression and a parameteric model, we show that this is the preferred solution to the current set of low-redshift ($z<3$) distance measurements if $H_0=73~\rm km\,s^{-1}\,Mpc^{-1}$ to within 1\% and the high-redshift expansion history is unchanged from the $\Lambda$CDM inference by the Planck satellite. Dark energy was effectively non-existent around $z=2$, but its density is close to the $\Lambda$CDM model value today, with an equation of state greater than $-1$ at $z<0.5$. If sources of clustering other than matter are negligible, we show that this expansion history leads to slower growth of perturbations at $z<1$, compared to $\Lambda$CDM, that is measurable by upcoming surveys and can alleviate the $\sigma_8$ tension between the Planck CMB temperature and low-redshift probes of the large-scale structure.Comment: 24 pages, 16 figure

Beyond Two Dark Energy Parameters

Our ignorance of the dark energy is generally described by a two-parameter equation of state. In these approaches a particular {\it ad hoc} functional form is assumed, and only two independent parameters are incorporated. We propose a model-independent, multi-parameter approach to fitting the dark energy, and show that next-generation surveys will constrain the equation of state in three or more independent redshift bins to better than 10%. Future knowledge of the dark energy will surpass two numbers (e.g., [$w_0$,$w_1$] or [$w_0$,$w_a$]), and we propose a more flexible approach to the analysis of present and future data.Comment: 4 pages, 1 figure; Discussion expanded to include next-generation BAO surveys and possible systematics in SN surveys; reflects version accepted for publication in Phys. Rev. Let

Characterization of long-term users of nicotine replacement therapy: evidence from a national survey

Introduction: Harm reduction involving partial or complete substitution of cigarettes with nicotine replacement therapy (NRT) is likely to benefit smokers by reducing exposure to carcinogens and by increasing the likelihood of permanent cessation. This article aimed to assess the determinants of short- and long-term NRT use for harm reduction in order to inform interventions aimed at helping smokers struggling to quit to switch to complete NRT substitution. / Methods: Data were used from the Smoking Toolkit Study, a population-based survey of adults in England aged 16 years and older (n = 9,224). Participants were asked about their sociodemographic characteristics and tobacco use. Attitudes toward smoking were also assessed using questions covering 4 factors: motives, identity, evaluations, and plans. / Results: Concurrent short-term (<3 months) and long-term (≥3 months) NRT use was uncommon among smokers at 10.8% (95% confidence interval [CI] = 10.1–11.4) and 5.0% (95% CI = 4.6–5.4), respectively. Long-term NRT users had higher odds of being older, in nonmanual occupations, and more addicted than smokers with short-term or no NRT use (all p < .01). They reported lower odds of attempting to stop and higher odds of exhibiting a positive smoker identity than short-term users (p < .001). Conversely, long-term NRT users had higher odds of having made a recent quit attempt, to have plans to stop, and lower odds of a positive smoker identity than smokers not using NRT (all p < .001). / Conclusions: While users of NRT for harm-reduction purposes are a heterogeneous group, it appears they are more critical of smoking than never users and tend to positively modulate their behavior, setting them on a path toward cessation

Timing and distributional aspects of transaction costs in Transferable Development Rights programmes

Planners are required to evaluate planning policy instruments to develop a better understanding of how they can improve their policy design and implementation processes. Transferable Development Rights (TDR) programmes are one of the market-based policy instruments that have attracted considerable attention among planners and economists. Given that TDR programmes have been introduced as an alternative to traditional regulatory instruments in several jurisdictions on the basis that their implementation will result in better policy outcomes, evaluation of these alternative programmes is particularly important. Like all policy instruments, the activities concerned with the design and implementation of TDR programmes may involve significant transaction costs. These activities can be considered as a series of transactions from the perspective of Transaction Cost Economics (TCE). While transaction costs are expected to vary across the lifecycle of a policy instrument, up to now there have been no systematic research studies concerned with why, and how, such transaction costs occur and are distributed among parties involved in different phases of TDR programmes. In order to aid better design and implementation of TDR programmes, this paper analyses the effects of transaction costs throughout the life of four TDR programmes (Calvert, Montgomery, St. Mary's, and Charles Counties) in the US state of Maryland in order to gain a better understanding of the timing and distribution of such costs incurred by different parties involved

Examining the influence of tobacco control mass media campaign expenditure on the association between motivation to stop smoking and quit attempts: A prospective study in England

OBJECTIVE: To explore whether expenditure on national tobacco control mass media campaigns moderates the association between motivation to stop smoking and future quit attempts. METHOD: Data were from 2601 people who smoke participating in a population survey with 12-month follow-up between April 2015 and February 2021. We used logistic regression to test associations of (i) baseline level of motivation to stop smoking, (ii) mean monthly tobacco control mass media campaign expenditure in England between baseline and follow-up, and (iii) their interaction, on past-year quit attempts assessed at 12-month follow-up. Covariates included age, sex, occupational social grade, and region. RESULTS: Between baseline and follow-up, 38.6% of participants made a quit attempt. Each one-point increase in baseline motivation to stop smoking was associated with 1.37 times greater odds (95%CI = 1.31-1.43) of making a quit attempt over 12-month follow-up. Each one standard deviation increase in tobacco control mass media expenditure between baseline and 12-month follow-up was associated with 13% greater odds of making a quit attempt (95%CI = 1.05-1.23). There was no significant interaction between mass media expenditure and motivation to stop on quit attempts (OR = 1.01, 95%CI = 0.97-1.05); the data provided strong evidence for the null (Bayes factors = 0.07 and 0.04 based on expected effect sizes of OR = 1.5 and OR = 0.67, respectively). CONCLUSIONS: Among people who smoke, self-reported level of motivation to stop strongly predicted whether they made a quit attempt in the subsequent year. Increased expenditure on tobacco control mass media campaigns was associated with increased quit attempts. The association between motivation and quit attempts did not differ according to tobacco control mass media expenditure over this period

Is dual use of nicotine products and cigarettes associated with smoking reduction and cessation behaviours? A prospective study in England

Objectives: To investigate associations of dual use of e-cigarettes and cigarettes with subsequent quitting activity (smoking reduction, quit attempts and use of evidence-based cessation aids). To overcome potential confounding by factors associated with use of pharmacological support, we selected dual use of over-the-counter nicotine replacement therapy (OTC NRT) and cigarettes as a behavioural control. / Design: Prospective cohort study with 6-month follow-up. / Setting: England, 2014–2016. / Participants: 413 current smokers participating in the Smoking Toolkit Study, a representative survey of adults in England, who reported current use of e-cigarettes or OTC NRT and provided data at 6-month follow-up. / Main: outcome measures The exposure was dual use of e-cigarettes or OTC NRT at baseline. Outcomes were change in cigarette consumption, quit attempts and use of evidence-based cessation aids during quit attempts over 6-month follow-up. Relevant sociodemographic and smoking characteristics were included as covariates. / Results: After adjustment for covariates, dual e-cigarette users smoked two fewer cigarettes per day at follow-up than at baseline compared with dual OTC NRT users (B=2.01, 95% CI −3.62; −0.39, p=0.015). While dual e-cigarette users had 18% lower odds than dual OTC NRT users to make a quit attempt at follow-up (risk ratio (RR) 0.82, 95% CI 0.67 to 1.00, p=0.049), the groups did not differ in use of cessation aids (RR 1.06, 95% CI 0.93 to 1.21, p=0.388). / Conclusions: Dual use of e-cigarettes is associated with a greater reduction in cigarette consumption than dual use of OTC NRT. It may discourage a small proportion of users from making a quit attempt compared with dual OTC NRT use but it does not appear to undermine use of evidence-based cessation aids

Impact of the cost-of-living crisis on the nature of attempts to stop smoking and to reduce alcohol consumption in Great Britain: A representative population survey, 2021-2022

BACKGROUND: Smoking and excessive drinking place a strain on household budgets. We aimed to examine the impact of the cost-of-living crisis in Great Britain on the nature of smoking cessation and alcohol reduction attempts, and explore changes in health professionals offering support. METHODS: Data were from 14,567 past-year smokers and high-risk drinkers (AUDIT-C ≥5) participating in monthly representative surveys, January-2021 through December-2022. We estimated time trends in cost as a motive driving the most recent (smoking cessation/alcohol reduction) attempt, use of paid or evidence-based support, and receipt of GP offer of support for smoking cessation or alcohol reduction, and tested for moderation by occupational social grade. RESULTS: The proportion of attempts motivated by cost did not change significantly over time among smokers (25.4% [95%CI = 23.8-26.9%]), but increased between December-2021 and December-2022 among high-risk drinkers from less advantaged social grades (from 15.3% [95%CI 12.1-19.3] to 29.7% [20.1-44.1]). The only change in support use was an increase in smokers using paid support, specifically e-cigarettes (from 28.1% [23.7-33.3] to 38.2% [33.0-44.4]). Among those visiting their GP, the proportion who received an offer of support was similar over time among smokers (27.0% [25.7-28.2]) and high-risk drinkers (1.4% [1.1-1.6%]). CONCLUSIONS: There is limited evidence that the 2021/22 cost-of-living crisis affected the nature of attempts to stop smoking and reduce alcohol consumption, or receipt of GP offer of support. It is encouraging that use of evidence-based support has not declined and that use of e-cigarettes in quit attempts has increased. However, cost is increasingly motivating alcohol reduction attempts among less advantaged drinkers, and rates of GPs offering support, especially for alcohol reduction, remain very low