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Service users as peer research interviewers: why bother?
Drawing on two studies completed within the social housing sector, this chapter asks if there are advantages to peer interviewing, whereby those currently or recently receiving services interview their peers as part of a research project. Contribution is made to the broader methodological debate of how service users should be involved in research about their lives. Along with contributions from a peer interviewer, we examine the benefits to peer interviewers themselves, and whether there are any positive differences for the people being interviewed. This chapter argues that there are clear methodological advantages to peer interviewing as it can lend vital insights from rapport with those often regarded as âhardest to reachâ. The chapter also discusses peer interviewing in terms of strategic risk and limitations, as well as practical and ethical considerations. Ways of developing peer research in general are also suggested
Deriving Supply-side Variables to Extend Geodemographic Classification
The traditional proprietary geodemographic information systems that are on the market today use well-established methodologies. Demographic indicators are selected as a proxy for affluence and are then often linked to customer databases to derive a measure of the level of consumption expected from the different area typologies. However, these systems ignore fundamental relationships in the retail market by focusing upon demand characteristics in a âvacuumâ and ignore the supply side and consumer-supplier interaction.
This paper argues that there may be considerable advantages to including supply-side indicators within geodemographic systems. Whilst the term âsupplyâ in this context might imply the number of consumer services already in an area, equally important for understanding demand are variables such as the supply of jobs and houses. We suggest that profiling an area in terms of its labour market characteristics gives a better insight into the income chain while the supply of houses could be argued to be a crucial factor in household formation that in turn will impact upon demographic structure. Using the regional example of Yorkshire and Humberside in northern England, we indicate how a suite of supply-side variables relating to the labour market can be assembled and used alongside a suite of demand variables to generate a new area classification. Spatial interaction models are calibrated to derive some of the variables that take into account zonal self-containment and catchment size
The ontogeny of sexual size dimorphism of a moth: when do males and females grow apart?
Sexual dimorphism in body size (sexual size dimorphism) is common in many species. The sources of selection that generate the independent evolution of adult male and female size have been investigated extensively by evolutionary biologists, but how and when females and males grow apart during ontogeny is poorly understood. Here we use the hawkmoth, Manduca sexta, to examine when sexual size dimorphism arises by measuring body mass every day during development. We further investigated whether environmental variables influence the ontogeny of sexual size dimorphism by raising moths on three different diet qualities (poor, medium and high). We found that size dimorphism arose during early larval development on the highest quality food treatment but it arose late in larval development when raised on the medium quality food. This female-biased dimorphism (females larger) increased substantially from the pupal-to-adult stage in both treatments, a pattern that appears to be common in Lepidopterans. Although dimorphism appeared in a few stages when individuals were raised on the poorest quality diet, it did not persist such that male and female adults were the same size. This demonstrates that the environmental conditions that insects are raised in can affect the growth trajectories of males and females differently and thus when dimorphism arises or disappears during development. We conclude that the development of sexual size dimorphism in M. sexta occurs during larval development and continues to accumulate during the pupal/adult stages, and that environmental variables such as diet quality can influence patterns of dimorphism in adults
Psychological targeting as an effective approach to digital mass persuasion
People are exposed to persuasive communication across many different contexts: governments, companies, and political parties use persuasive appeals to encourage people to eat healthier, purchase a particular product, or vote for a specific candidate. Laboratory studies show that such persuasive appeals are more effective in influencing behavior when they are tailored to individualsâ unique psychological characteristics. Yet, the investigation of large-scale psychological persuasion in the real world has been hindered by the questionnaire-based nature of psychological assessment. Recent research, however, shows that peopleâs psychological characteristics can be accurately predicted from their digital footprints, such as their Facebook Likes or Tweets. Capitalizing on this new form of psychological assessment from digital footprints, we test the effects of psychological persuasion on peopleâs actual behavior in an ecologically valid setting. In three field experiments that reached over 3.5 million individuals with psychologically-tailored advertising, we find that matching the content of persuasive appeals to individualsâ psychological characteristics significantly altered their behavior as measured by clicks and purchases. Persuasive appeals that were matched to peopleâs extraversion or openness-to-experience level resulted in up to 40% more clicks and up to 50% more purchases than their mismatching or un-personalized counterparts. Our findings suggest that the application of psychological targeting makes it possible to influence the behavior of large groups of people by tailoring persuasive appeals to the psychological needs of the target audiences. We discuss both the potential benefits of this method for helping individuals make better decisions and the potential pitfalls related to manipulation and privacy
Preparation and characterization of PLGA particles for subcutaneous controlled drug release by membrane emulsification
Uniformly sized microparticles of poly(DL, lactic-co-glycolic) (PLGA) acid, with controllable
median diameters within the size range 40 to 140 microns, were successfully prepared by
membrane emulsification of an oil phase injected into an aqueous phase, followed by solvent
removal. Initially, simple particles were produced as an oil-in-water emulsion, where
dichloromethane (DCM) and PLGA were the oil phase and water with stabiliser was the
continuous phase. The oil was injected into the aqueous phase through an array type
microporous membrane, which has very regular pores equally spaced apart, and two different
pore sizes were used: 20 and 40 microns in diameter. Shear was provided at the membrane
surface, causing the drops to detach, by a simple paddle stirrer rotating above the membrane.
Further tests involved the production of a primary water-in-oil emulsion, using a mechanical
homogeniser, which was then subsequently injected into a water phase through the
microporous membrane to form a water-in-oil-in-water emulsion. These tests used a water
soluble model drug (blue dextran) and encapsulation efficiencies of up to 100% were obtained
for concentrations of 15% PLGA dissolved in the DCM and injected through a 40 micron
membrane.
Solidification of the PLGA particles followed by removal of the DCM through the surrounding
aqueous continuous phase. Different PLGA concentrations, particle size and osmotic
pressures were considered in order to find their effect on encapsulation efficiency. Osmotic
pressure was varied by changing the salt concentration in the external aqueous phase whilst
maintaining a constant internal aqueous phase salt concentration. Osmotic pressure was
found to be a significant factor on the resulting particle structure, for the tests conducted at
lower PLGA concentrations (10 and 5% PLGA). The PLGA concentration and particle size
distribution influence the time to complete the solidification stage and a slow solidification,
formed by stirring gently overnight, provided the most monosized particles and highest
encapsulation efficiency
On Dijkgraaf-Witten Type Invariants
We explicitly construct a series of lattice models based upon the gauge group
which have the property of subdivision invariance, when the coupling
parameter is quantized and the field configurations are restricted to satisfy a
type of mod- flatness condition. The simplest model of this type yields the
Dijkgraaf-Witten invariant of a -manifold and is based upon a single link,
or -simplex, field. Depending upon the manifold's dimension, other models
may have more than one species of field variable, and these may be based on
higher dimensional simplices.Comment: 18 page
Classical simulation of measurement-based quantum computation on higher-genus surface-code states
We consider the efficiency of classically simulating measurement-based
quantum computation on surface-code states. We devise a method for calculating
the elements of the probability distribution for the classical output of the
quantum computation. The operational cost of this method is polynomial in the
size of the surface-code state, but in the worst case scales as in the
genus of the surface embedding the code. However, there are states in the
code space for which the simulation becomes efficient. In general, the
simulation cost is exponential in the entanglement contained in a certain
effective state, capturing the encoded state, the encoding and the local
post-measurement states. The same efficiencies hold, with additional
assumptions on the temporal order of measurements and on the tessellations of
the code surfaces, for the harder task of sampling from the distribution of the
computational output.Comment: 21 pages, 13 figure
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