How do preferences for public health interventions differ? a case study using a weight loss maintenance intervention

PhD ThesisPreference information is routinely used in healthcare decision-making, such as in health technology assessment, where preferences for health states are used to estimate quality-adjusted life years. However, there is debate over whose preferences should be considered. This debate extends to other areas in health economics where preferences are elicited to inform decision-making. Common stated preference methodologies include discrete choice experiments (DCEs) and contingent valuation (CV), which produce information that can be used in economic evaluations and benefit-risk assessments. This thesis expands the ‘preference debate’ beyond health utilities by considering the use of DCE and CV studies in decision-making. It also extends the debate by considering more than ‘patients’ and the general population; introducing four user groups that differ in their relative experience. The thesis’ aim is to explore whether, and how, differences in individuals’ experience of a healthcare intervention/health issue might influence preferences. It uses a weight loss maintenance intervention from the NULevel trial (ISRCTN14657176) as a case study. Chapter One introduces the thesis premise and Chapter Two outlines the economic theory underpinning the methodologies used. Chapter Three discusses the use of economic evaluation, providing a review of the ‘preference debate’ and recent developments. CV and DCE methodologies are next outlined and the use of information from DCEs in healthcare decision-making reviewed. Chapter Four systematically reviews the DCE literature in health economics to determine whether respondents can be classified as either a patient or general population sample. Building upon previous chapters, Chapter Five introduces an alternative framework for classifying respondent samples in DCE studies in terms of their relative experience; this defines the user groups for the empirical work (conducted via NULevel and an online panel). The research questions are next outlined. Chapter Six summarises the NULevel trial, the recruitment plan and the online survey design (containing both a DCE and CV task) used to address the research questions. Chapters Seven to Nine present results and Chapter Ten provides a discussion of implications, strengths and limitations of the work. The empirical work suggests that preferences differ according to the relative experience of respondents; raising concerns surrounding the generalisability of DCE studies. This is important given the increasing application of preference studies in decision-making. If this trend continues the implications will be even greater in future.the Health Foundatio

Measurements of the Complex Conductivity of NbxSi1-x Alloys on the Insulating Side of the Metal-Insulator Transition

We have conducted temperature and frequency dependent transport measurements in amorphous Nb_x Si_{1-x} samples in the insulating regime. We find a temperature dependent dc conductivity consistent with variable range hopping in a Coulomb glass. The frequency dependent response in the millimeter-wave frequency range can be described by the expression $sigma(omega) \propto (-\imath omega)^alpha$ with the exponent somewhat smaller than one. Our ac results are not consistent with extant theories for the hopping transport.Comment: 4 pages with 3 figures; published version has a different title from original (was: "Electrodynamics in a Coulomb glass"

A Genome-Wide Association Study for Regulators of Micronucleus Formation in Mice.

In mammals the regulation of genomic instability plays a key role in tumor suppression and also controls genome plasticity, which is important for recombination during the processes of immunity and meiosis. Most studies to identify regulators of genomic instability have been performed in cells in culture or in systems that report on gross rearrangements of the genome, yet subtle differences in the level of genomic instability can contribute to whole organism phenotypes such as tumor predisposition. Here we performed a genome-wide association study in a population of 1379 outbred Crl:CFW(SW)-US_P08 mice to dissect the genetic landscape of micronucleus formation, a biomarker of chromosomal breaks, whole chromosome loss, and extranuclear DNA. Variation in micronucleus levels is a complex trait with a genome-wide heritability of 53.1%. We identify seven loci influencing micronucleus formation (false discovery rate <5%), and define candidate genes at each locus. Intriguingly at several loci we find evidence for sexual dimorphism in micronucleus formation, with a locus on chromosome 11 being specific to males.This work was supported by Cancer Research UK and the Wellcome Trust.This is the final version of the article. It first appeared from the Genetics Society of America via http://dx.doi.org/10.1534/g3.116.03076

U.S. Army Small Space Update

In December 2010, the U.S. Army flew its first satellite in 50 years, the SMDC-ONE CubeSat. Placed in a very low orbit, the first SMDC-ONE mission lasted only 35 days but enjoyed great success in demonstrating the viability of CubeSats to perform exfiltration of unattended ground sensors data and serve as a communications relay between ground stations over 1000 land miles apart. The success of SMDC-ONE helped shape the U.S. Army’s Space and Missile Defense Command’s (SMDC) programmatic goals for finding new and innovative ways to implement space applications and technologies that aid the warfighter. Since 2010, SMDC has flown ten additional CubeSats including the three SMDC Nanosatellite Program-3 (SNaP) CubeSats currently on orbit (launched October 2015). This paper addresses several SMDC satellite-related development efforts including SNaP, Army Resilient Global On-the-move SATCOM (ARGOS) Ka-band communications microsatellites, Kestrel Eye (an imaging microsatellite), Kestrel Eye Ground Station (KEGS), Common Ground Station (CGS) for all future Army small satellites, supporting technologies including Small Business Innovative Research (SBIR) efforts, the Concepts Analysis Laboratory, SMDC Space Laboratory, the ACES RED effort and earlier responsive launch vehicle activities. Several of the lessons learned from previous as well as ongoing satellite activities are also covered

Detectors for the James Webb Space Telescope Near-Infrared Spectrograph I: Readout Mode, Noise Model, and Calibration Considerations

We describe how the James Webb Space Telescope (JWST) Near-Infrared Spectrograph's (NIRSpec's) detectors will be read out, and present a model of how noise scales with the number of multiple non-destructive reads sampling-up-the-ramp. We believe that this noise model, which is validated using real and simulated test data, is applicable to most astronomical near-infrared instruments. We describe some non-ideal behaviors that have been observed in engineering grade NIRSpec detectors, and demonstrate that they are unlikely to affect NIRSpec sensitivity, operations, or calibration. These include a HAWAII-2RG reset anomaly and random telegraph noise (RTN). Using real test data, we show that the reset anomaly is: (1) very nearly noiseless and (2) can be easily calibrated out. Likewise, we show that large-amplitude RTN affects only a small and fixed population of pixels. It can therefore be tracked using standard pixel operability maps.Comment: 55 pages, 10 figure

Constipation and a Low-Fiber Diet Are Not Associated With Diverticulosis

Asymptomatic diverticulosis is commonly attributed to constipation secondary to a low-fiber diet, although evidence for this mechanism is limited. We examined the associations between constipation and low dietary fiber intake with risk of asymptomatic diverticulosis

A simple spontaneously active Hebbian learning model: homeostasis of activity and connectivity, and consequences for learning and epileptogenesis

A spontaneously active neural system that is capable of continual learning should also be capable of homeostasis of both firing rate and connectivity. Experimental evidence suggests that both types of homeostasis exist, and that connectivity is maintained at a state that is optimal for information transmission and storage. This state is referred to as the critical state. We present a simple stochastic computational Hebbian learning model that incorporates both firing rate and critical homeostasis, and we explore its stability and connectivity properties. We also examine the behavior of our model with a simulated seizure and with simulated acute deafferentation. We argue that a neural system that is more highly connected than the critical state (i.e., one that is "supercritical") is epileptogenic. Based on our simulations, we predict that the post-seizural and post-deafferentation states should be supercritical and epileptogenic. Furthermore, interventions that boost spontaneous activity should be protective against epileptogenesis.Comment: 37 pages, 1 table, 7 figure