957 research outputs found

    Enhanced magnetic Purcell effect in room-temperature masers

    Get PDF
    Recently, the world’s first room-temperature maser was demonstrated. The maser consisted of a sapphire ring housing a crystal of pentacene-doped p-terphenyl, pumped by a pulsed rhodamine-dye laser. Stimulated emission of microwaves was aided by the high quality factor and small magnetic mode volume of the maser cavity yet the peak optical pumping power was 1.4 kW. Here we report dramatic miniaturization and 2 orders of magnitude reduction in optical pumping power for a room-temperature maser by coupling a strontium titanate resonator with the spin-polarized population inversion provided by triplet states in an optically excited pentacene-doped p-terphenyl crystal. We observe maser emission in a thimble-sized resonator using a xenon flash lamp as an optical pump source with peak optical power of 70 W. This is a significant step towards the goal of continuous maser operation

    Conceptualising the right to data protection in an era of Big Data

    Get PDF
    In 2009, with the enactment of the Lisbon Treaty, the Charter of Fundamental Rights of the European Union entered into force. Under Article 8 of the Charter, for the first time, a stand-alone fundamental right to data protection was declared. The creation of this right, standing as a distinct right to the right to privacy, is undoubtedly significant, and it is unique to the European legal order, being absent from other international human rights instruments. This commentary examines the parameters of this new right to data protection, asking what are the principles underpinning the right. It argues that the right reflects some key values inherent in the European legal order, namely: privacy, transparency, autonomy and nondiscrimination. It also analyses some of the challenges in implementing this right in an era of ubiquitous veillance practices and Big Data

    Dual-gated bilayer graphene hot electron bolometer

    Full text link
    Detection of infrared light is central to diverse applications in security, medicine, astronomy, materials science, and biology. Often different materials and detection mechanisms are employed to optimize performance in different spectral ranges. Graphene is a unique material with strong, nearly frequency-independent light-matter interaction from far infrared to ultraviolet, with potential for broadband photonics applications. Moreover, graphene's small electron-phonon coupling suggests that hot-electron effects may be exploited at relatively high temperatures for fast and highly sensitive detectors in which light energy heats only the small-specific-heat electronic system. Here we demonstrate such a hot-electron bolometer using bilayer graphene that is dual-gated to create a tunable bandgap and electron-temperature-dependent conductivity. The measured large electron-phonon heat resistance is in good agreement with theoretical estimates in magnitude and temperature dependence, and enables our graphene bolometer operating at a temperature of 5 K to have a low noise equivalent power (33 fW/Hz1/2). We employ a pump-probe technique to directly measure the intrinsic speed of our device, >1 GHz at 10 K.Comment: 5 figure

    A mobile phone app to support young people in making shared decisions in therapy (Power Up): study protocol

    Get PDF
    Background: Evidence suggests that young people want to be active participants in their care and involved in decisions about their treatment. However, there is a lack of digital shared decision-making tools available to support young people in child and adolescent mental health services (CAMHS). Objective: The primary aim of this paper is to present the protocol of a feasibility trial for Power Up, a mobile phone app to empower young people in CAMHS to make their voices heard and participate in decisions around their care. Methods: In the development phase, 30 young people, parents, and clinicians will take part in interviews and focus groups to elicit opinions on an early version of the app. In the feasibility testing phase, 60 young people from across 7 to 10 London CAMHS sites will take part in a trial looking at the feasibility and acceptability of measuring the impact of Power Up on shared decision making. Results: Data collection for the development phase ended in December 2016. Data collection for the feasibility testing phase will end in December 2017. Conclusions: Findings will inform the planning of a cluster controlled trial and contribute to the development and implementation of a shared decision-making app to be integrated into CAMHS

    Big data: Finders keepers, losers weepers?

    Get PDF
    This article argues that big data’s entrepreneurial potential is based not only on new technological developments that allow for the extraction of non-trivial, new insights out of existing data, but also on an ethical judgment that often remains implicit: namely the ethical judgment that those companies that generate these new insights can legitimately appropriate (the fruits of) these insights. As a result, the business model of big data companies is essentially founded on a libertarian-inspired ‘finders, keepers’ ethic. The article argues, next, that this presupposed ‘finder, keepers’ ethic is far from unproblematic and relies itself on multiple unconvincing assumptions. This leads to the conclusion that the conduct of companies working with big data might lack ethical justification

    Incarcerated transmesosigmoid hernia presenting in a 60-year-old man: a case report

    Get PDF
    © 2008 Collins et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens

    Genome-wide DNA methylation analysis for diabetic nephropathy in type 1 diabetes mellitus

    Get PDF
    BACKGROUND: Diabetic nephropathy is a serious complication of diabetes mellitus and is associated with considerable morbidity and high mortality. There is increasing evidence to suggest that dysregulation of the epigenome is involved in diabetic nephropathy. We assessed whether epigenetic modification of DNA methylation is associated with diabetic nephropathy in a case-control study of 192 Irish patients with type 1 diabetes mellitus (T1D). Cases had T1D and nephropathy whereas controls had T1D but no evidence of renal disease. METHODS: We performed DNA methylation profiling in bisulphite converted DNA from cases and controls using the recently developed Illumina Infinium(R) HumanMethylation27 BeadChip, that enables the direct investigation of 27,578 individual cytosines at CpG loci throughout the genome, which are focused on the promoter regions of 14,495 genes. RESULTS: Singular Value Decomposition (SVD) analysis indicated that significant components of DNA methylation variation correlated with patient age, time to onset of diabetic nephropathy, and sex. Adjusting for confounding factors using multivariate Cox-regression analyses, and with a false discovery rate (FDR) of 0.05, we observed 19 CpG sites that demonstrated correlations with time to development of diabetic nephropathy. Of note, this included one CpG site located 18 bp upstream of the transcription start site of UNC13B, a gene in which the first intronic SNP rs13293564 has recently been reported to be associated with diabetic nephropathy. CONCLUSION: This high throughput platform was able to successfully interrogate the methylation state of individual cytosines and identified 19 prospective CpG sites associated with risk of diabetic nephropathy. These differences in DNA methylation are worthy of further follow-up in replication studies using larger cohorts of diabetic patients with and without nephropathy

    Genes Suggest Ancestral Colour Polymorphisms Are Shared across Morphologically Cryptic Species in Arctic Bumblebees

    Get PDF
    email Suzanne orcd idCopyright: © 2015 Williams et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

    Beyond the security paradox:Ten criteria for a socially informed security policy

    Get PDF
    This article is based on a research that has been funded by the EU project “SurPriSe: Surveillance, Privacy and Security: A large scale participatory assessment of criteria and factors determining acceptability and acceptance of security technologies in Europe”, which received funding from the FP7 program, under the grant number: 285492.This article investigates the normative and procedural criteria adopted by European citizens to assess the acceptability of surveillance-oriented security technologies. It draws on qualitative data gathered at 12 citizen summits in nine European countries. The analysis identifies 10 criteria, generated by citizens themselves, for a socially informed security policy. These criteria not only reveal the conditions, purposes and operation rules that would make current European security policies and technologies more consistent with citizens’ priorities. They also cast light on an interesting paradox: although people feel safe in their daily lives, they believe security could, and should, be improved.PostprintPeer reviewe
    corecore