4,721 research outputs found

    Commercial conflict and regulation in the discourse of trade in seventeenth-century England

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    This article seeks to re-examine the intellectual context of commercial policy and regulation in seventeenth-century England. It questions a common assumption about so-called ‘mercantilist’ writers: that they saw trade as in some way finite and therefore won by one nation at the expense of another. Instead, it proposes that the often belligerent attitude of the ‘mercantilists’ towards trade was rooted in an understanding of the nature of international commerce as both communication and competition. Although writers acknowledged the mutual aspect of trade, they did not see this exchange as automatically equal, but saw it as possible for one party to exploit the other. This situation demanded state action to protect national trading interests in the disputed area of commerce, and thus this ‘discourse of trade’ was linked to political and juridical discourses about international relations. The article shows how this understanding of trade influenced debates about commercial governance in the critical middle decades of the seventeenth century, culminating in the attempt to create a national monopoly through the navigation acts, ‘securing sovereignty’ over the nation's trade. The second half of this article examines this in more detail with reference to the ideas of a prominent defender of the 1651 Navigation Act: Benjamin Worsley

    Superconductivity under pressure in the Dirac semimetal PdTe2

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    The Dirac semimetal PdTe2_2 was recently reported to be a type-I superconductor (Tc=T_c = 1.64 K, μ0Hc(0)=13.6\mu_0 H_c (0) = 13.6 mT) with unusual superconductivity of the surface sheath. We here report a high-pressure study, p≤2.5p \leq 2.5 GPa, of the superconducting phase diagram extracted from ac-susceptibility and transport measurements on single crystalline samples. Tc(p)T_c (p) shows a pronounced non-monotonous variation with a maximum Tc=T_c = 1.91 K around 0.91 GPa, followed by a gradual decrease to 1.27 K at 2.5 GPa. The critical field of bulk superconductivity in the limit T→0T \rightarrow 0, Hc(0,p)H_c(0,p), follows a similar trend and consequently the Hc(T,p)H_c(T,p)-curves under pressure collapse on a single curve: Hc(T,p)=Hc(0,p)[1−(T/Tc(p))2]H_c(T,p)=H_c(0,p)[1-(T/T_c(p))^2]. Surface superconductivity is robust under pressure as demonstrated by the large superconducting screening signal that persists for applied dc-fields Ha>HcH_a > H_c. Surprisingly, for p≥1.41p \geq 1.41 GPa the superconducting transition temperature at the surface TcST_c^S is larger than TcT_c of the bulk. Therefore surface superconductivity may possibly have a non-trivial nature and is connected to the topological surface states detected by ARPES. We compare the measured pressure variation of TcT_c with recent results from band structure calculations and discuss the importance of a Van Hove singularity.Comment: manuscript 9 pages with 8 figures + supplemental material 3 pages with 6 figure

    Patient and Public Involvement in the Development of Healthcare Guidance: An Overview of Current Methods and Future Challenges

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    Clinical guidelines and health technology assessments are valuable instruments to improve the quality of healthcare delivery and aim to integrate the best available evidence with real-world, expert context. The role of patient and public involvement in their development has grown in recent decades, and this article considers the international literature exploring aspects of this participation, including the integration of experiential and scientific knowledge, recruitment strategies, models of involvement, stages of involvement, and methods of evaluation. These developments have been underpinned by the parallel rise of public involvement and evidence-based medicine as important concepts in health policy. Improving the recruitment of guideline group chairs, widening evidence reviews to include patient preference studies, adapting guidance presentation to highlight patient preference points and providing clearer instructions on how patient organisations can submit their intelligence are emerging proposals that may further enhance patient and public involvement in their processes

    Epitaxial growth of high quality WO3 thin films

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    We have grown epitaxial WO3 films on various single-crystal substrates using radio frequency magnetron sputtering. While pronounced surface roughness is observed in films grown on LaSrAlO4 substrates, films grown on Y AlO3 substrates show atomically flat surfaces, as demonstrated by atomic force microscopy and X-ray diffraction (XRD) measurements. The crystalline structure has been confirmed to be monoclinic by symmetric and skew-symmetric XRD. The dependence of the growth modes and the surface morphology on the lattice mismatch are discussed

    Daytime napping, sleep duration and increased 8-year risk of type 2 diabetes in a British population.

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    BACKGROUND AND AIMS: Few studies have prospectively examined the relationship between daytime napping and risk of type 2 diabetes. We aimed to study the effects of daytime napping and the joint effects of napping and sleep duration in predicting type 2 diabetes risk in a middle- to older-aged British population. METHODS AND RESULTS: In 1998-2000, 13 465 individuals with no known diabetes participating in the European Prospective Investigation into Cancer-Norfolk study reported daytime napping habit and 24-h sleep duration. Incident type 2 diabetes cases were identified through multiple data sources until 31 July 2006. After adjustment for age and sex, daytime napping was associated with a 58% higher diabetes risk. Further adjustment for education, marital status, smoking, alcohol intake, physical activity, comorbidities and hypnotic drug use had little influence on the association, but additional adjustment for BMI and Waist Circumference attenuated the Odds ratio (OR) (95% CI) to 1.30 (1.01, 1.69). The adjusted ORs (95% CI) associated with short and long sleep duration were 1.46 (1.10, 1.90) and 1.64 (1.16, 2.32), respectively. When sleep duration and daytime napping were examined together, the risk of developing diabetes more than doubled for those who took day naps and had less than 6 h of sleep, compared to those who did not nap and had 6-8 h of sleep. CONCLUSION: Daytime napping was associated with an increased risk of type 2 diabetes, particularly when combined with short sleep duration. Further physiological studies are needed to confirm the interaction between different domains of sleep in relation to diabetes risk.The design and conduct of the EPIC-Norfolk study and collection and management of the data was supported by programme grants from the Medical Research Council UK (G9502233, G0300128) and Cancer Research UK (C865/A2883). Funding sources did not have a role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; and preparation, review, or approval of the manuscript.This is the final version of the article. It first appeared from Elsevier at http://dx.doi.org/10.1016/j.numecd.2016.06.006

    Analysis of rolling contact spall life in 440 C steel bearing rims

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    The results of a two year study of the mechanisms of spall failure in the HPOTP bearings are described. The objective was to build a foundation for detailed analyses of the contact life in terms of: cyclic plasticity, contact mechanics, spall nucleation, and spall growth. Since the laboratory rolling contact testing is carried out in the 3 ball/rod contact fatigue testing machine, the analysis of the contacts and contact lives produced in this machine received attention. The results from the experimentally observed growth lives are compared with calculated predictions derived from the fracture mechanics calculations
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