1,890 research outputs found

    Spontaneous breaking of time reversal symmetry in strongly interacting two dimensional electron layers in silicon and germanium

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    We report experimental evidence of a remarkable spontaneous time reversal symmetry breaking in two dimensional electron systems formed by atomically confined doping of phosphorus (P) atoms inside bulk crystalline silicon (Si) and germanium (Ge). Weak localization corrections to the conductivity and the universal conductance fluctuations were both found to decrease rapidly with decreasing doping in the Si:P and Ge:P δ\delta-layers, suggesting an effect driven by Coulomb interactions. In-plane magnetotransport measurements indicate the presence of intrinsic local spin fluctuations at low doping, providing a microscopic mechanism for spontaneous lifting of the time reversal symmetry. Our experiments suggest the emergence of a new many-body quantum state when two dimensional electrons are confined to narrow half-filled impurity bands

    I have my MBA – Now What?

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    Although it is assumed that gaining an advanced degree should make a student more attractive to a potential employer little current data is available on the value that employers may place on such credentials. The UB Business School graduate population is an equal mix of domestic and international students. Historically it has been assumed that the international student wants to return to his or her native country. The goal of this research will be to inform the faculty at the Business School as to the employment objectives of international MBA students

    Advancing the application of systems thinking in health : sustainability evaluation as learning and sense-making in a complex urban health system in Northern Bangladesh

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    Municipalities are legally tasked with ensuring the delivery of primary health care services to the population but had developed almost no capacity to do so. We describe how the Sustainability Framework method was implemented following the mid-term evaluation (2002), up through the final evaluation (2004), all the way to the 5-year post-project sustainability evaluation in 2009. Development aid’s efforts at scale up and acceleration of achievements are known to create stress on country systems, regardless of good intentions. This makes the question of sustainability still enormously critical to the future of global health and global development

    Treatment of neonatal infections: a multi-country analysis of health system bottlenecks and potential solutions.

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    BACKGROUND: Around one-third of the world's 2.8 million neonatal deaths are caused by infections. Most of these deaths are preventable, but occur due to delays in care-seeking, and access to effective antibiotic treatment with supportive care. Understanding variation in health system bottlenecks to scale-up of case management of neonatal infections and identifying solutions is essential to reduce mortality, and also morbidity. METHODS: A standardised bottleneck analysis tool was applied in 12 countries in Africa and Asia as part of the development of the Every Newborn Action Plan. Country workshops involved technical experts to complete a survey tool, to grade health system "bottlenecks" hindering scale up of maternal-newborn intervention packages. Quantitative and qualitative methods were used to analyse the data, combined with literature review, to present priority bottlenecks and synthesise actions to improve case management of newborn infections. RESULTS: For neonatal infections, the health system building blocks most frequently graded as major or significant bottlenecks, irrespective of mortality context and geographical region, were health workforce (11 out of 12 countries), and community ownership and partnership (11 out of 12 countries). Lack of data to inform decision making, and limited funding to increase access to quality neonatal care were also major challenges. CONCLUSIONS: Rapid recognition of possible serious bacterial infection and access to care is essential. Inpatient hospital care remains the first line of treatment for neonatal infections. In situations where referral is not possible, the use of simplified antibiotic regimens for outpatient management for non-critically ill young infants has recently been reported in large clinical trials; WHO is developing a guideline to treat this group of young infants. Improving quality of care through more investment in the health workforce at all levels of care is critical, in addition to ensuring development and dissemination of national guidelines. Improved information systems are needed to track coverage and adequately manage drug supply logistics for improved health outcomes. It is important to increase community ownership and partnership, for example through involvement of community groups

    Antimicrobial activity of Mycobacteriophage D29 Lysin B during Mycobacterium ulcerans infection

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    Buruli Ulcer (BU) is a necrotizing skin disease caused by Mycobacterium ulcerans. Although the current antibiotic treatment for BU is effective, daily administrations for a prolonged period of time, combined with potential risk of severe side effects, negatively impact on patient adherence. In that sense, we tested the efficacy of an alternative strategy based on Lysin B (LysB), a phage encoded lipolytic enzyme that degrades the mycolylarabinogalactan-peptidoglycan complex present in the mycobacterial cell wall. In this study, we show that LysB not only displays lytic activity against M. ulcerans isolates in vitro, but also leads to a decrease of M. ulcerans proliferation in infected mouse footpads. These findings highlight the potential use of lysins as a novel therapeutic approach against this neglected tropical disease.The projectwas developed withinthescopeof the projectsNORTE-01-0145-FEDER-000013and NORTE-01-0145-FEDER-000023,supported by the Northern Portugal Regional Operational Programme (NORTE2020),under the Portugal2020 Partnership Agreement through FEDER.This work was also supported by BioTecNorte operation (NORTE-01-0145-FEDER -000004) funded by the European Regional Development Fund under the scope of NORTE2020.This study was supportedby the Portuguese Foundation for Scienceand Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit; the Competitiveness Factors Operational Programme (COMPETE 2020) projectsPOCI-01-0145-FEDER-006684 and POCI-01-0145-FEDER-007038; and the project PTDC/BBB-BSS/6471/2014 (POCI-01-0145-FEDER-016678). This study was also supported by Infect-ERA grant Infect-ERA/0002/2015 :BU_SPONT_HEAL. AGF,GT, and HO wouldlike to acknowledge FCT for the individual fellowships SFRH/BPD/112903/2015, SFRH/BPD/64032/2009,and SFRH/BPD/111653/2015,respectively. CMG received an individual QRENfellowship (UMINHO/BPD/15/2014). GangaGen acknowledges CSIR/ OSDD,Govt of India,for funding this project.The funders had no role in study design,data collection and analysis, decision to publish, or preparation of the manuscriptinfo:eu-repo/semantics/publishedVersio

    Contemporary themes in the design of AT for the ageing population: materiality, co-design and cultural influences

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    Products we purchase are much more than artefacts that fulfil functional needs in our life. We have grown to enact our consumer choices, even those regarding fast moving consumable goods, with careful considerations informed by numerous trials, recommendations and, growingly, environmental concerns in mind. Advanced manufacturing and progress in research and development are providing more choices for consumers even in quite specific and complex product markets. An exemption to this market trend is represented by assistive technologies (ATs). This is a relatively underdeveloped context despite the growing demands for assistive devices by those in later life who need either support in accomplishing everyday life to stay independent or have complex co-occurring conditions. In this chapter, we explore why ATs, especially for older adults, are underdeveloped by exploring issues related to design approaches and cultural and social perceptions that have contributed to making consumers more or less sensitive and demanding towards the role of ATs in their lives. The chapter will conclude with recommendations that may be able to shift the perception of assistive devices so as to facilitate the user’s emotional investment in the devices, attachment to them, which, in return, may lead to better adherence and faster adoption

    CTCF loss has limited effects on global genome architecture in Drosophila despite critical regulatory functions.

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    Vertebrate genomes are partitioned into contact domains defined by enhanced internal contact frequency and formed by two principal mechanisms: compartmentalization of transcriptionally active and inactive domains, and stalling of chromosomal loop-extruding cohesin by CTCF bound at domain boundaries. While Drosophila has widespread contact domains and CTCF, it is currently unclear whether CTCF-dependent domains exist in flies. We genetically ablate CTCF in Drosophila and examine impacts on genome folding and transcriptional regulation in the central nervous system. We find that CTCF is required to form a small fraction of all domain boundaries, while critically controlling expression patterns of certain genes and supporting nervous system function. We also find that CTCF recruits the pervasive boundary-associated factor Cp190 to CTCF-occupied boundaries and co-regulates a subset of genes near boundaries together with Cp190. These results highlight a profound difference in CTCF-requirement for genome folding in flies and vertebrates, in which a large fraction of boundaries are CTCF-dependent and suggest that CTCF has played mutable roles in genome architecture and direct gene expression control during metazoan evolution

    Robotic-Assisted Surgery for Benign Urological Conditions

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    Robotic technology for use in surgery has advanced considerably in the past 10 years. This has become particularly apparent in urology where robotic-assisted radical prostatectomy using the da VinciTM surgical system (Intuitive Surgical, CA) has become very popular. The use of robotic assistance for benign urological procedures is less well documented. This article considers the current robotic technology and reviews the situation with regard to robotic surgery for benign urological conditions

    Bottom-up assembly of metallic germanium

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    Extending chip performance beyond current limits of miniaturisation requires new materials and functionalities that integrate well with the silicon platform. Germanium fits these requirements and has been proposed as a high-mobility channel material, a light emitting medium in silicon-integrated lasers, and a plasmonic conductor for bio-sensing. Common to these diverse applications is the need for homogeneous, high electron densities in three-dimensions (3D). Here we use a bottom-up approach to demonstrate the 3D assembly of atomically sharp doping profiles in germanium by a repeated stacking of two-dimensional (2D) high-density phosphorus layers. This produces high-density (1019 to 1020 cm-3) low-resistivity (10-4Ω ∙ cm) metallic germanium of precisely defined thickness, beyond the capabilities of diffusion-based doping technologies. We demonstrate that free electrons from distinct 2D dopant layers coalesce into a homogeneous 3D conductor using anisotropic quantum interference measurements, atom probe tomography, and density functional theory
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