267 research outputs found

    Perfect Quantum Routing in Regular Spin Networks

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    Regular families of coupled quantum networks are described such the unknown state of a qubit can be perfectly routed from any node to any other node in a time linear in the distance. Unlike previous constructions, the transfer can be achieved perfectly on a network that is local on any specified number of spatial dimensions. The ability to route the state, and the regularity of the networks, vastly improve the utility of this scheme in comparison to perfect state transfer schemes. The structures can also be used for entanglement generation.Comment: 4 pages, 3 figure

    Quantum Control Theory for State Transformations: Dark States and their Enlightenment

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    For many quantum information protocols such as state transfer, entanglement transfer and entanglement generation, standard notions of controllability for quantum systems are too strong. We introduce the weaker notion of accessible pairs, and prove an upper bound on the achievable fidelity of a transformation between a pair of states based on the symmetries of the system. A large class of spin networks is presented for which this bound can be saturated. In this context, we show how the inaccessible dark states for a given excitation-preserving evolution can be calculated, and illustrate how some of these can be accessed using extra catalytic excitations. This emphasises that it is not sufficient for analyses of state transfer in spin networks to restrict to the single excitation subspace. One class of symmetries in these spin networks is exactly characterised in terms of the underlying graph properties.Comment: 14 pages, 3 figures v3: rewritten for increased clarit

    A protocol for a systematic review of clinical guidelines and published systematic reviews on the early detection of oral cancer

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    Background: The predicted increase in incidence of oral cavity cancer (OCC) coupled with high mortality and poor prognosis – particularly when diagnosed at a late/advanced stage – highlights the need for prevention and early detection/screening to reverse these trends. Dental healthcare professionals in primary care settings have a pivotal role in this effort. Aim: The aim of this protocol is to detail the process for assessing the evidence for the best practice and methods of early detection/screening for OCC in primary care dental settings by undertaking a systematic review of global clinical guidelines and published systematic reviews. Method: Searches for clinical guidelines and systematic reviews will be conducted in the following databases: Cochrane library, Medical Literature Analysis and Retrieval System Online (Ovid), Excerpta Medical dataBASE, PubMed, Turning Research into Practice, SCOPUS and Web of Science Core Collection. Our search will extend to include Google Scholar and international professional organizations/associations websites. In addition, we will handsearch the bibliographies and undertake citation searches of the selected papers. Quality appraisal will be undertaken using the Appraisal of Guidelines for Research and Evaluation version II instrument for the clinical guidelines and both A MeaSurement Tool to Assess Systematic Reviews and Risk of Bias in Systematic Reviews tools for the systematic reviews. A narrative synthesis approach will be used to assess the evidence of extracted data, primarily taking account of quality appraisal and recency of publication. Discussion: The synthesis of evidence will determine best practice for OCC early detection/screening by primary care dental healthcare professionals and will evaluate the relationship between clinical guidelines and the evidence base available from systematic reviews in this area

    The effectiveness of Dental Health Support Workers at linking families with primary care dental practices: a population-wide data linkage cohort study

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    Background: Link workers (lay health workers, health support workers) based in the community provide additional support to individuals and families to facilitate engagement with primary care and other services and resources. This additional support aims to tackle the wider socio-economic determinants of health that lead to inequalities. To date, there is no clear evidence of the effectiveness of these programmes. This study evaluates the effectiveness of Dental Health Support Workers (DHSW) at linking targeted families with young children to primary care dental practices. The DHSW role is one component of Childsmile, the national oral health improvement programme in Scotland. Methods: A quasi-experimental approach captured the natural variation in the rollout of the DHSW intervention across Scotland in a cohort of children born between 2010 and 2013. Survival analysis explored “time to attendance” at primary care dental practice. Cox’s regression models compared attendance rates and time until first attendance between those families who received support from the DHSW and those who did not. Results: The cohort consisted of 35236 children. Thirty-three percent of the cohort (n = 11495) were considered to require additional support from a DHSW. Of these, 44% (5087) received that support. These families were more likely to attend a dental practice (Hazard Ratio [95% Confidence Interval] =1.87 [1.8 to 1.9]) and, on average, did so 9 months earlier (median time until first attendance: 8.8 months versus 17.8 months), compared to families not receiving additional support. Conclusions: Link workers (DHSW) within the Childsmile programme are effective at linking targeted children to primary care dental services and, most notably, at a younger age for prevention. This is the first study of its kind to evaluate the effectiveness of link-worker programmes using a robust quasi-experimental design on three, population-wide, linked datasets. These results will inform future health programmes which aim to improve health and reduce inequalities by reaching and supporting families from more disadvantaged backgrounds

    Assessment and prevention of behavioural and social risk factors associated with oral cancer: protocol for a systematic review of clinical guidelines and systematic reviews to inform primary care dental professionals

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    Background: Tobacco and alcohol are recognised as the major risk factors for both oral cavity (mouth) and oropharyngeal (throat) cancers, with increasing acceptance of the role of human papillomavirus (HPV) in the aetiology of oropharyngeal cancers. In addition, there is a significant increased risk for oral cancer among lower socioeconomic groups, males and older age groups. There is a growing evidence for the potential role of primary care professionals in smoking cessation and reducing alcohol-related harm. However, there are uncertainties about the best approaches/strategies to assess risk factors associated with oral cancer, effective components of preventive interventions for behaviour change and implementation strategies in primary care dental settings. Thus, in order to contribute to the prevention of oral cancer effectively, dental professionals need to assess patients on the major risk factors (tobacco, alcohol and HPV/sexual behaviours) and deliver appropriate prevention, taking into account the patient’s sociodemographic context. Aim: The study aims to synthesise evidence on the best practice for undertaking an assessment of major behavioural risk factors associated with oral cancer and delivering effective behaviour change preventive interventions (e.g. advice, counselling, patient recall, signposting/referral to preventive services) by dental professionals in primary care dental settings. Method: The study involves a systematic review and evidence appraisal. We will search for clinical guidelines and systematic reviews from the following databases: Cochrane Library, Ovid MEDLINE, EMBASE, Web of Science, PsychINFO, PubMed, TRIP and Google Scholar. We will also search websites of professional organisations/agencies and bibliographies/reference lists of selected papers. Quality will be assessed with the AGREE II (Appraisal of Guidelines for Research & Evaluation II) instrument for included clinical guidelines and the AMSTAR (A Measurement Tool to Assess Systematic Reviews) and ROBIS instruments for included systematic reviews. The best practice evidence will be assessed via a narrative synthesis of extracted data, considering publication quality. Discussion: This systematic review will synthesise evidence on the best practice for oral cancer risk factor assessment and prevention and evaluate the relationship between available clinical guidelines and the review evidence base. This collation of evidence will be useful for making recommendations for future intervention, research and guideline development

    Hard rock landforms generate 130 km ice shelf channels through water focusing in basal corrugations

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    This work is licensed under a Creative Commons Attribution 4.0 International License.Satellite imagery reveals flowstripes on Foundation Ice Stream parallel to ice flow, and meandering features on the ice-shelf that cross-cut ice flow and are thought to be formed by water exiting a well-organised subglacial system. Here, ice-penetrating radar data show flow-parallel hard-bed landforms beneath the grounded ice, and channels incised upwards into the ice shelf beneath meandering surface channels. As the ice transitions to flotation, the ice shelf incorporates a corrugation resulting from the landforms. Radar reveals the presence of subglacial water alongside the landforms, indicating a well-organised drainage system in which water exits the ice sheet as a point source, mixes with cavity water and incises upwards into a corrugation peak, accentuating the corrugation downstream. Hard-bedded landforms influence both subglacial hydrology and ice-shelf structure and, as they are known to be widespread on formerly glaciated terrain, their influence on the ice-sheet-shelf transition could be more widespread than thought previously.NASA grant # NNX10AT68GANT # NT-0424589University of KansasUK NERC AFI grant NE/G013071/

    Proteolysis-inducing factor core peptide mediates dermcidin-induced proliferation of hepatic cells through multiple signalling networks

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    Dermcidin is a candidate oncogene capable of increasing the number of cultured neuronal, breast cancer and prostate cancer cells and improving the survival of hepatic cells. The dermcidin gene encodes the proteolysis-inducing factor core peptide (PIF-CP) and the skin antimicrobial peptide DCD-1. The peptide responsible for inducing proliferation of cells and the mechanisms involved are unknown. In this study, we confirmed a proliferative effect of dermcidin over-expression of 20% (p<0.02) in the HuH7 human hepatic cell line. Proliferation was abrogated by prevention of PIF-CP translation or inactivation of its calcineurin-like phosphatase domain by site-directed mutagenesis. Prevention of DCD-1 translation had no effect. Treatment of cells with a 30 amino acid synthetic PIF-CP induced an analogous increase in proliferation of 14%. Microarray analysis of PIF-CP-treated cells revealed low but significant changes in 111 potential mediator genes. Pathway analysis revealed several gene networks involved in the cellular response to the peptide, one with VEGFB as a hub and two other networks converging on FOS and MYC. Quantitative PCR confirmed direct upregula-tion of VEGFB. These data reveal PIF-CP as the key mediator of dermcidin-induced proliferation and demonstrate induction of key oncogenic pathways

    Risk prediction models for head and neck cancer: a rapid review

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    Background: Cancer risk assessment models are used to support prevention and early detection. However, few models have been developed for head and neck cancer (HNC). Methods: A rapid review of Embase and MEDLINE identified n = 3045 articles. Following dual screening, n = 14 studies were included. Quality appraisal using the PROBAST (risk of bias) instrument was conducted, and a narrative synthesis was performed to identify the best performing models in terms of risk factors and designs. Results: Six of the 14 models were assessed as “high” quality. Of these, three had high predictive performance achieving area under curve values over 0.8 (0.87–0.89). The common features of these models were their inclusion of predictors carefully tailored to the target population/anatomical subsite and development with external validation. Conclusions: Some existing models do possess the potential to identify and stratify those at risk of HNC but there is scope for improvement

    Head and neck cancer in the UK: what was the stage before COVID-19? UK cancer registries analysis (2011-2018)

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    Introduction: People who present with more advanced stage head and neck cancer (HNC) are associated with poorer outcomes and survival. The burden and trends of advanced stage HNC are not fully known at the population level. The UK national cancer registries routinely collect data on HNC diagnoses. Aims: To describe trends in stage of diagnosis of HNCs across the UK before the COVID-19 pandemic. Methods: Aggregated HNC incidence data were requested from the national cancer registries of the four UK countries for the ten most recent years of available data by subsite and American Joint Commission on Cancer stage at diagnosis classification. Additionally, data for Scotland were available by age group, sex and area-based socioeconomic deprivation category. Results: Across the UK, rates of advanced stage HNC had increased, with 59% of patients having advanced disease at diagnosis from 2016-2018. England had a lower proportion of advanced disease (58%) than Scotland, Wales or Northern Ireland (65-69%) where stage data were available. The completeness of stage data had improved over recent years (87% by 2018). Conclusion: Prior to the COVID-19 pandemic, diagnoses of HNC at an advanced stage comprised the majority of HNCs in the UK, representing the major challenge for the cancer healthcare system
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