John of Worcester and the science of history

Although the ‘chronicle of chronicles’ compiled at Worcester c1095-c1140 is now firmly attributed to John of Worcester, rather than Florence, major questions remain. A central issue is that the semi-autograph manuscript of the chronicle (now Oxford, Corpus Christi College, Ms 157) underwent several alterations to its structure and contents, as codicological evidence demonstrates. These included the incorporation of important illuminations, which have been surprisingly little considered in their overall manuscript context. This article focuses on these illuminations, and will argue that their presence in this version of the chronicle makes it something even more distinctive than the learned, revisionist chronological work of Marianus Scotus upon which it was based. John of Worcester’s chosen images are linked not only to his political narrative but also to theological works and to cutting-edge science, newly translated from Arabic. The presence of such miniatures in a twelfth-century chronicle is unique, and they are central to the final form given to the Worcester chronicle by John of Worcester himself in this key manuscript. Their analysis thus brings into focus the impressive assembly of materials which the chronicle offered to readers, to shape their understanding of ongoing events.

Essays on labour market dualisation in Western Europe: active labour market policies, temporary work regulation and inequality

European labour markets are increasingly divided between insiders in full-time permanent employment and outsiders in precarious work or unemployment. Using quantitative as well as qualitative methods, this thesis investigates the determinants and consequences of labour market policies that target these outsiders in three separate papers. The first paper looks at Active Labour Market Policies (ALMPs) that target the unemployed. It shows that left and right-wing parties choose different types of ALMPs depending on the policy and the welfare regime in which the party is located. These findings reconcile the conflicting theoretical expectations from the Power Resource approach and the insider-outsider theory. The second paper considers the regulation and protection of the temporary work sector. It solves the puzzle of temporary re-regulation in France, which contrasts with most other European countries that have deregulated temporary work. Permanent workers are adversely affected by the expansion of temporary work in France because of general skills and low wage coordination. The interests of temporary and permanent workers for re-regulation therefore overlap in France and left governments have an incentive to re-regulate the sector. The third paper then investigates what determines inequality between median and bottom income workers. It shows that non-inclusive economic coordination increases inequality in the absence of compensating institutions such as minimum wage regulation. The deregulation of temporary work as well as spending on employment incentives and rehabilitation also has adverse effects on inequality. Thus, policies that target outsiders have important economic effects on the rest of the workforce. Three broader contributions can be identified. First, welfare state policies may not always be in the interests of labour, so left parties may not always promote them. Second, the interests of insiders and outsiders are not necessarily at odds. Third, economic coordination may not be conducive to egalitarianism where it is not inclusive.

The dangers of hanging baskets: 'Regulatory myths' and media representations of health and safety regulation

The successful enforcement of health and safety regulation is reliant upon the ability of regulatory agencies to demonstrate the legitimacy of the system of regulatory controls. While 'big cases' are central to this process, there are also significant legitimatory implications associated with 'minor' cases, including media-reported tales of pettiness and heavy-handedness in the interpretation and enforcement of the law. The popular media regularly report stories of 'regulatory unreasonableness', and they can pass quickly into mainstream public knowledge. A story's appeal becomes more important than its factual veracity; they are a form of 'regulatory myth'. This paper discusses the implications of regulatory myths for health and safety regulators, and analyses their challenges for regulators, paying particular attention to the Health and Safety Executive (HSE) which has made concerted efforts to address regulatory myths attaching to its activities. It will be shown that such stories constitute sustained normative challenges to the legitimacy of the regulator, and political challenges to the burgeoning regulatory state, because they reflect some of the key concerns of late-modern society.

Biosecurity in agriculture: an economic analysis of coexistence of professional and hobby production

One component of biosecurity is protection against invasive alien species, which are one of the most important threats worldwide to native biodiversity and economic profitability in various sectors, including agriculture. However, agricultural producers are not homogeneous. They may have different objectives and priorities, use different technologies, and occupy heterogeneous parcels of land. If the producers differ in terms of their attitude towards invasive pests and the damages they cause, there are probably external effects in the form of pest spread impacts and subsequent damages caused. We study such impacts in the case of two producer types: profit-seeking professional producers and utility-seeking hobby producers. We show that the hobby producer, having first set a breeding ground for the pest, under-invests in pest control. We also discuss potential policy instruments to correct this market failure and highlight the importance of considering different stakeholders and their heterogeneous incentives when designing policies to control invasive alien species.

Micellar and surface properties of a poly(methyl methacrylate)-block-poly(N-isopropylacrylamide) copolymer in aqueous solution

Critical micelle concentrations (cmc) of aqueous solutions of poly(methyl methacrylate)-block-poly(N-isopropylacrylamide) were determined at several temperatures by surface tensiometry. Below the lower critical solution temperature (LCST), the low Delta(mic) H-0 determined can be assigned to the PMMA block being tightly coiled in the dispersed molecular state, so that the unfavorable interactions of hydrophobic entities with water are minimized. Above the LCST the cmc value was found to increase; an anomalous behavior that can be directly related to the micelle-globule transition of the hydrophilic block. Interestingly, above the LCST the surface tension of relatively concentrated solutions was found to depend weakly on temperature not following the usual strong decrease with temperature expected for aqueous solutions. (C) 2007 Elsevier Inc. All rights reserved.

Structure, rheology and shear alignment of Pluronic block copolymer mixtures

The structure and flow behaviour of binary mixtures of Pluronic block copolymers P85 and P123 is investigated by small-angle scattering, rheometry and mobility tests. Micelle dimensions are probed by dynamic light scattering. The micelle hydrodynamic radius for the 50/50 mixture is larger than that for either P85 or P123 alone, Clue to the formation of mixed micelles with a higher association number. The phase diagram for 50/50 mixtures contains regions Of Cubic and hexagonal phases similar to those for the parent homopolymers, however the region of stability of the cubic phase is enhanced at low temperature and concentrations above 40 wt%. This is ascribed to favourable packing of the mixed micelles containing core blocks with two different chain lengths, but similar corona chain lengths. The shear flow alignment of face-centred cubic and hexagonal phases is probed by in situ small-angle X-ray or neutron scattering with simultaneous rheology. The hexagonal phase can be aligned using steady shear in a Couette geometry, however the high modulus Cubic phase cannot be aligned well in this way. This requires the application of oscillatory shear or compression. (C) 2008 Elsevier Inc. All rights reserved.

Effect of water-soluble polymers, polyethylene glycol and poly(vinylpyrrolidone),on the gelation of aqueous micellar solutions of Pluronic copolymer F127

The micellization of F127 (E98P67E98) in dilute aqueous solutions of polyethylene glycol (PEG6000 and PEG35000) and poly(vinylpyrrolidone) (PVP K30 and PVP K90) is studied. The average hydrodynamic radius (rh,app) obtained from the dynamic light scattering technique increased with increase in PEG concentration but decreased on addition of PVP, results which are consistent with interaction of the micelles with PEG and the formation of micelles clusters, but no such interaction occurs with PVP. Tube inversion was used to determine the onset of gelation. The critical concentration of F127 for gelation increased on addition of PEG and of PVP K30 but decreased on addition of PVP K90. Small-angle X-ray scattering (SAXS) was used to show that the 30 wt% F127 gel structure (fcc) was independent of polymer type and concentration, as was the d-spacing and so the micelle hard-sphere radius. The maximum elastic modulus (G0 max) of 30 wt% F127 decreased from its value for water alone as PEG was added, but was little changed by adding PVP. These results are consistent with the packed-micelles in the 30 wt% F127 gel being effectively isolated from the polymer solution on the microscale while, especially for the PEG, being mixed on the macroscale.

Synergetic effect of carbon nanopore size and surface oxidation on CO2 capture from CO2/CH4 mixtures

We have studied the synergetic effect of confinement (carbon nanopore size) and surface chemistry (the number of carbonyl groups) on CO2 capture from its mixtures with CH4 at typical operating conditions for industrial adsorptive separation (298 K and compressed CO2CH4 mixtures). Although both confinement and surface oxidation have an impact on the efficiency of CO2/CH4 adsorptive separation at thermodynamics equilibrium, we show that surface functionalization is the most important factor in designing an efficient adsorbent for CO2 capture. Systematic Monte Carlo simulations revealed that adsorption of CH4 either pure or mixed with CO2 on oxidized nanoporous carbons is only slightly increased by the presence of functional groups (surface dipoles). In contrast, adsorption of CO2 is very sensitive to the number of carbonyl groups, which can be examined by a strong electric quadrupolar moment of CO2. Interestingly, the adsorbed amount of CH4 is strongly affected by the presence of the co-adsorbed CO2. In contrast, the CO2 uptake does not depend on the molar ratio of CH4 in the bulk mixture. The optimal carbonaceous porous adsorbent used for CO2 capture near ambient conditions should consist of narrow carbon nanopores with oxidized pore walls. Furthermore, the equilibrium separation factor was the greatest for CO2/CH4 mixtures with a low CO2 concentration. The maximum equilibrium separation factor of CO2 over CH4 of ∼18–20 is theoretically predicted for strongly oxidized nanoporous carbons. Our findings call for a review of the standard uncharged model of carbonaceous materials used for the modeling of the adsorption separation processes of gas mixtures containing CO2 (and other molecules with strong electric quadrupolar moment or dipole moment).

Effect of Rht alleles on the tolerance of wheat grain set to high temperature and drought stress during booting and anthesis

Factorial pot experiments were conducted to compare the responses of GA-sensitive and GA-insensitive reduced height (Rht) alleles in wheat for susceptibility to heat and drought stress during booting and anthesis. Grain set (grains/spikelet) of near isogenic lines (NILs) was assessed following three day transfers to controlled environments imposing day temperatures (t) from 20 to 40°C. Transfers were during booting and/or anthesis and pots maintained at field capacity (FC) or had water withheld. Logistic responses (y = c/1+e-b(t -m)) described declining grain set with increasing t, and t5 was that fitted to give a 5% reduction in grain set. Averaged over NIL, t5 for anthesis at FC was 31.7±0.47°C (S.E.M, 26 d.f.). Drought at anthesis reduced t5 by <2°C. Maintaining FC at booting conferred considerable resistance to high temperatures (t5=33.9°C) but booting was particularly heat susceptible without water (t5 =26.5°C). In one background (cv. Mercia), for NILs varying at the Rht-D1 locus, there was progressive reduction in t5 with dwarfing and reduced gibberellic acid (GA) sensitivity (Rht-D1a, tall, 32.7±0.72; Rht-D1b, semi-dwarf, 29.5±0.85; Rht-D1c, severe dwarf, 24.2±0.72). This trend was not evident for the Rht-B1 locus, or for Rht-D1b in an alternative background (Maris Widgeon). The GA-sensitive severe dwarf Rht12 was more heat tolerant (t5=29.4±0.72) than the similarly statured GA-insensitive Rht-D1c. The GA-sensitive, semi-dwarfing Rht8 conferred greater drought tolerance in one experiment. Despite the effects of Rht-D1 alleles in Mercia on stress tolerance, the inconsistency of the effects over background and locus led to the conclusion that semi-dwarfing with GA-insensitivity did not necessarily increase sensitivity to stress at booting and flowering. In comparison to effects of semi-dwarfing alleles, responses to heat stress are much more dramatically affected by water availability and the precise growth stage at which the stress is experienced by the plants.

Government policy under price uncertainty: a source of volatility in illegal immigration

In this paper we provide an alternative explanation for why illegal immigration can exhibit substantial fluctuation. We develop a model economy in which migrants make decisions in the face of uncertain border enforcement and lump-sum transfers from the host country. The uncertainty is extrinsic in nature, a sunspot, and arises as a result of ambiguity regarding the commodity price of money. Migrants are restricted from participating in state-contingent insurance markets in the host country, whereas host country natives are not. Volatility in migration flows stems from two distinct sources: the tension between transfers inducing migration and enforcement discouraging it and secondly the existence of a sunspot. Finally, we examine the impact of a change in tax/transfer policies by the government on migration.

The aims of early years outdoor education in England: a conceptual and empirical investigation

This paper explores the place of aims in the early years foundation stage outdoor environment in England. Through examining the writing of academics, various themes are identified, and constructed into possible aims. These themes/aims are compared to an empirical study of early years teachers’ attitudes. Data was collected by questionnaire from schools within the University of Reading partnership. There was general agreement between experts and teachers as to the aims. While some respondents were able to explain what the aims of outdoor activity were, a significant number were unable to identify aims; further, a significant number did not distinguish between approach/practice and aims. A lack of understanding and agreement as to what the aims are may indicate teachers are unsure about the purpose of outdoor education for young children. A result of this study is to agree and make explicit the aims for outdoor education in the early years.