Informed consent and placebo effects: a content analysis of information leaflets to identify what clinical trial participants are told about placebos

BackgroundPlacebo groups are used in randomised clinical trials (RCTs) to control for placebo effects, which can be large. Participants in trials can misunderstand written information particularly regarding technical aspects of trial design such as randomisation; the adequacy of written information about placebos has not been explored. We aimed to identify what participants in major RCTs in the UK are told about placebos and their effects.Methods and FindingsWe conducted a content analysis of 45 Participant Information Leaflets (PILs) using quantitative and qualitative methodologies. PILs were obtained from trials on a major registry of current UK clinical trials (the UKCRN database). Eligible leaflets were received from 44 non-commercial trials but only 1 commercial trial. The main limitation is the low response rate (13.5%), but characteristics of included trials were broadly representative of all non-commercial trials on the database. 84% of PILs were for trials with 50:50 randomisation ratios yet in almost every comparison the target treatments were prioritized over the placebos. Placebos were referred to significantly less frequently than target treatments (7 vs. 27 mentions, p<001) and were significantly less likely than target treatments to be described as triggering either beneficial effects (1 vs. 45, p<001) or adverse effects (4 vs. 39, p<001). 8 PILs (18%) explicitly stated that the placebo treatment was either undesirable or ineffective.ConclusionsPILs from recent high quality clinical trials emphasise the benefits and adverse effects of the target treatment, while largely ignoring the possible effects of the placebo. Thus they provide incomplete and at times inaccurate information about placebos. Trial participants should be more fully informed about the health changes that they might experience from a placebo. To do otherwise jeopardises informed consent and is inconsistent with not only the science of placebos but also the fundamental rationale underpinning placebo controlled trials

Conductivity of 2D many-component electron gas, partially-quantized by magnetic field

The 2D semimetal consisting of heavy holes and light electrons is studied. The consideration is based on assumption that electrons are quantized by magnetic field while holes remain classical. We assume also that the interaction between components is weak and the conversion between components is absent. The kinetic equation for holes colliding with quantized electrons is utilized. It has been stated that the inter-component friction and corresponding correction to the dissipative conductivity $\sigma_{xx}$ {\it do not vanish at zero temperature} due to degeneracy of the Landau levels. This correction arises when the Fermi level crosses the Landau level. The limits of kinetic equation applicability were found. We also study the situation of kinetic memory when particles repeatedly return to the points of their meeting.Comment: 13 pages, 1 figur

A fully coupled 3D transport model in SPH for multi-species reaction-diffusion systems

In this paper we present a fully generalized transport model for multiple species in complex two and three-dimensional geometries. Based on previous work [1] we have extended our interfacial reaction-diffusion model to handle arbitrary numbers of species allowing for coupled reaction models. Each species is tracked independently and we consider different physics of a species with respect to the bulk phases in contact. We use our SPH model to simulate the reaction-diffusion problem on a pore-scale level of a solid oxide fuel cell (SOFC) with special emphasize on the effect of surface diffusion

Facilitating urban renewal: changing institutional arrangements and land assembly in Hong Kong

Purpose: The paper examines the operation of the Land (compulsory sale for redevelopment) Ordinance, one of a series of urban renewal policy initiatives introduced by the Hong Kong Government. The new institutional arrangement was mooted as a means to facilitate greater private sector participation in the renewal process by overcoming existing constraints on land assembly, which arise as the result of a system of common property ownership. The paper investigates whether the legislation can achieve the objective of encouraging private sector participation in the urban renewal process Design/methodology/approach: The paper adopts a transaction cost framework, drawn from literature and applied in the context of real estate, to examine the effects of a new Ordinance. In addition to publicly available data, semi‐structured interviews were conducted with professionals involved in urban renewal and representatives from the property development companies. The apparently low usage of the new approach is explored in the context of the various alternative mechanisms for land assembly available to the private sector and the effects of transactions costs on developer behaviour. Findings: The paper identifies that the relatively low usage of the Ordinance may be explained by institutional constraints and limitations in the legislation, which, in its current form, fails to provide sufficient incentives, but that developer behaviour may also be affected by other external factors. Research limitations/implications: The research is limited in that any commentary on the effectiveness of the legislation in achieving its objectives is restricted by the inability to clearly identify those incidences where the threat of legal action was sufficient to achieve a negotiated acquisition of the necessary property rights. Further research might explore the implications and the inter‐relationships between the various urban renewal initiatives introduced by the Hong Kong Government. Practical implications: The recent experience of the Hong Kong Government in designing a new institutional mechanism to overcome problems of private sector land assembly for properties in multiple‐ownership may offer more general lessons for those in similar environments who wish to use the resources of the private sector to contribute to the urban renewal process. Originality/value: The paper adopts a transaction cost approach to examine the working of a new policy initiative for facilitating land assembly in Hong Kong and may be of interest to academics and practitioners involved in the area of urban renewal

Urban renewal in Hong Kong: transition from development corporation to renewal authority

This paper assesses the record of Hong Kong's Land Development Corporation and considers the reasons for its recent transformation into an Urban Renewal Authority. After reviewing the Corporation's first two phases of projects launched in 1988 and 1992, the paper examines how the Hong Kong Government failed to equip it with adequate powers and resources. As a result, although the LDC certainly established itself as an important actor in urban redevelopment, its own flagship projects took much longer to deliver than originally anticipated and did not produce any major restructuring of land use patterns or transport networks. This recent experience of urban renewal in Hong Kong offers more general lessons for renewal policy elsewhere. These concern the nature of public–private relations, the importance of effective linkages between strategic planning and implementation and the dangers of uncritical policy transfer from one locale to another

Nontangential limits and Fatou-type theorems on post-critically finite self-similar sets

In this paper we study the boundary limit properties of harmonic functions on $\mathbb R_+\times K$, the solutions $u(t,x)$ to the Poisson equation $$\frac{\partial^2 u}{\partial t^2} + \Delta u = 0,$$ where $K$ is a p.c.f. set and $\Delta$ its Laplacian given by a regular harmonic structure. In particular, we prove the existence of nontangential limits of the corresponding Poisson integrals, and the analogous results of the classical Fatou theorems for bounded and nontangentially bounded harmonic functions.Comment: 22 page

Reproducing Kernels of Generalized Sobolev Spaces via a Green Function Approach with Distributional Operators

In this paper we introduce a generalized Sobolev space by defining a semi-inner product formulated in terms of a vector distributional operator $\mathbf{P}$ consisting of finitely or countably many distributional operators $P_n$, which are defined on the dual space of the Schwartz space. The types of operators we consider include not only differential operators, but also more general distributional operators such as pseudo-differential operators. We deduce that a certain appropriate full-space Green function $G$ with respect to $L:=\mathbf{P}^{\ast T}\mathbf{P}$ now becomes a conditionally positive definite function. In order to support this claim we ensure that the distributional adjoint operator $\mathbf{P}^{\ast}$ of $\mathbf{P}$ is well-defined in the distributional sense. Under sufficient conditions, the native space (reproducing-kernel Hilbert space) associated with the Green function $G$ can be isometrically embedded into or even be isometrically equivalent to a generalized Sobolev space. As an application, we take linear combinations of translates of the Green function with possibly added polynomial terms and construct a multivariate minimum-norm interpolant $s_{f,X}$ to data values sampled from an unknown generalized Sobolev function $f$ at data sites located in some set $X \subset \mathbb{R}^d$. We provide several examples, such as Mat\'ern kernels or Gaussian kernels, that illustrate how many reproducing-kernel Hilbert spaces of well-known reproducing kernels are isometrically equivalent to a generalized Sobolev space. These examples further illustrate how we can rescale the Sobolev spaces by the vector distributional operator $\mathbf{P}$. Introducing the notion of scale as part of the definition of a generalized Sobolev space may help us to choose the "best" kernel function for kernel-based approximation methods.Comment: Update version of the publish at Num. Math. closed to Qi Ye's Ph.D. thesis (\url{http://mypages.iit.edu/~qye3/PhdThesis-2012-AMS-QiYe-IIT.pdf}

The first ever anti-football painting: A consideration of the soccer match in John Singer Sargent’s "Gassed"

The paper presents a discussion of Gassed, a large oil painting by John Singer Sargent displayed at the Imperial War Museum in London. Completed in 1919, Gassed is the major achievement from Sargent’s commission as an official war artist at the appointment of the British War Memorials Committee during the latter period of World War I. Prominent in the painting is a group of soldiers, blinded by a mustard gas attack, being lead to a casualty clearing station tent. In the distant background of the painting, another group of soldiers can be seen kitted out in football attire playing a match. The significance of this football imagery is our point of enquiry. As our title suggests, some recent interpretations regard the painting as offering critical reflection, from the time, about the symbolic links between sport and war. However, while the painting may certainly be left open to this type of viewer interpretation, archival and secondary resource material research does not support such a critical intention by the artist. Yet, nor is there evidence that Sargent’s intention was the projection of war-heroism. Rather, Sargent’s endeavour to faithfully represent what he observed allows Gassed to be regarded as a visual record of routine activity behind the lines and of football as an aspect of the daily life of British soldiers during the Great War