5,097 research outputs found

    Reflection Symmetries for Multiqubit Density Operators

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    For multiqubit density operators in a suitable tensorial basis, we show that a number of nonunitary operations used in the detection and synthesis of entanglement are classifiable as reflection symmetries, i.e., orientation changing rotations. While one-qubit reflections correspond to antiunitary symmetries, as is known for example from the partial transposition criterion, reflections on the joint density of two or more qubits are not accounted for by the Wigner Theorem and are well-posed only for sufficiently mixed states. One example of such nonlocal reflections is the unconditional NOT operation on a multiparty density, i.e., an operation yelding another density and such that the sum of the two is the identity operator. This nonphysical operation is admissible only for sufficiently mixed states.Comment: 9 page

    Visualising the structure of document search results: A comparison of graph theoretic approaches

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    This is the post-print of the article - Copyright @ 2010 Sage PublicationsPrevious work has shown that distance-similarity visualisation or ‘spatialisation’ can provide a potentially useful context in which to browse the results of a query search, enabling the user to adopt a simple local foraging or ‘cluster growing’ strategy to navigate through the retrieved document set. However, faithfully mapping feature-space models to visual space can be problematic owing to their inherent high dimensionality and non-linearity. Conventional linear approaches to dimension reduction tend to fail at this kind of task, sacrificing local structural in order to preserve a globally optimal mapping. In this paper the clustering performance of a recently proposed algorithm called isometric feature mapping (Isomap), which deals with non-linearity by transforming dissimilarities into geodesic distances, is compared to that of non-metric multidimensional scaling (MDS). Various graph pruning methods, for geodesic distance estimation, are also compared. Results show that Isomap is significantly better at preserving local structural detail than MDS, suggesting it is better suited to cluster growing and other semantic navigation tasks. Moreover, it is shown that applying a minimum-cost graph pruning criterion can provide a parameter-free alternative to the traditional K-neighbour method, resulting in spatial clustering that is equivalent to or better than that achieved using an optimal-K criterion

    Rates of psychotropic medicine prescribing in paediatric populations in Australian general practice from 2000-2016

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    General practitioner (GP) prescribing of psychotropic medicines to paediatric patients is increasing across countries, sparking the need for additional research into this field. We examined prescribing rates, GP and patient characteristics and indications associated with prescribing psychotropic medicines to paediatric patients in Australian general practice, using data from the Bettering the Evaluation and Care of Health (BEACH) program. We extracted all encounters with children aged 3 to 17 from 2000 to 2016. Psychotropic medicines were defined as those in the ATC codes N05 (Psycholeptics) and N06 (Psychoanaleptics). Of the 144,397 encounters, GPs prescribed 1829 psychotropic medicines to paediatric patients at an average rate of 1.16 prescriptions per 100 encounters (95% confidence interval 1.09–1.23). We found that the rate of psychotropic medicines prescribed to paediatric patients in Australian general practice increased. Patients who were adolescent, female, socio-economically disadvantaged or from an English-speaking background were significantly more likely to be prescribed a psychotropic medicine. GP practices in remote or regional areas and Australian graduate GPs were more likely to prescribe psychotropic medicines to paediatric patients. Depression, attention deficit hyperactivity disorder, anxiety and autism were the most common psychiatric indications managed with psychotropic medicines. Antidepressants, psychostimulants, benzodiazepines, antipsychotics and other psychotropic medicines were prescribed, signifying a high rate of off-label use. Sertraline was the most common psychotropic medicine prescribed, followed by fluoxetine and methylphenidate. Future studies involving data from other prescribers, e.g. paediatricians and psychiatrists, and studies linking prescribed medicines to their indications may widen our understanding of psychotropic medicine prescribing in Australian paediatric patients

    Exploring stakeholders' perspectives on the quality of services provided through community pharmacies

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    Introduction - It is important to understand the factors impacting the quality of services provided through community pharmacies. Exploring how key stakeholders perceive good quality in these services is a logical first step. This could also inform the development of quality measures, such as quality indicators (QIs). Aim - To identify key stakeholders' perspectives on the quality of services provided through community pharmacies in Norway, specifically by exploring their experiences and perceptions about what constitutes good service quality. Methods - A convenient sampling approach was used to recruit participants for five semi-structured focus groups from Facebook, pharmacy chains, and patient organizations. The interviews with twenty-six participants were conducted via Microsoft Teams. Interviews were transcribed verbatim, and an inductive thematic analysis with a reflexive approach was used. Results - Four main themes emerged from the analysis; 1) sufficient and substantively suitable information to cover individual needs, 2) communication skills and relationships with the pharmacy professionals, 3) customer satisfaction with knowledgeable employees and conveniently located pharmacies, and 4) factors that affect the pharmacy working environment. Conclusion - This study has identified areas that pharmacy professionals and customers regard as essential to define good quality of community pharmacy services. Effective communication skills, appropriate provision of information, customer satisfaction, and working environment are all essential factors when developing quality metrics for community pharmacies

    Comparison of drug-related problem risk assessment tools for older adults : a systematic review

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    Purpose This study aims to systematically review studies describing screening tools that assess the risk for drug-related problems (DRPs) in older adults (>= 60 years). The focus of the review is to compare DRP risks listed in different tools and describe their development methods and validation. Methods The systematic search was conducted using evidence-based medicine, Medline Ovid, Scopus, and Web of Science databases from January 1, 1985, to April 7, 2016. Publications describing general DRP risk assessment tools for older adults written in English were included. Disease, therapy, and drug-specific tools were excluded. Outcome measures included an assessment tool's content, development methods, and validation assessment. Results The search produced 15 publications describing 11 DRP risk assessment tools. Three major categories of risks for DRPs included (1) patient or caregiver related risks; (2) pharmacotherapy-related risks; and (3) medication use process-related risks. Of all the risks included in the tools only 8 criteria appeared in at least 4 of the tools, problems remembering to take the medication being the most common (n=7). Validation assessments varied and content validation was the most commonly conducted (n = 9). Reliability assessment was conducted for 6 tools, most commonly by calculating internal consistency (n = 3) and inter-rater reliability (n = 2). Conclusions The considerable variety between the contents of the tools indicates that there is no consensus on the risk factors for DRPs that should be screened in older adults taking multiple medicines. Further research is needed to improve the accuracy and timeliness of the DRP risk assessment tools.Peer reviewe

    The relationship between web enjoyment and student perceptions and learning using a web-based tutorial

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    Web enjoyment has been regarded as a component of system experience. However, there has been little targeted research considering the role of web enjoyment alone in student learning using web-based systems. To address this gap, this study aims to examine the influence of web enjoyment on learning performance and perceptions by controlling system experience as a variable in the study. 74 students participated in the study, using a web-based tutorial covering subject matter in the area of 'Computation and algorithms'. Their learning performance was assessed with a pre-test and a post-test and their learning perceptions were evaluated with a questionnaire. The results indicated that there are positive relationships between the levels of web enjoyment and perceived usefulness and non-linear navigation for users with similar, significant levels of system experience. The implications of these findings in relation to web-based learning are explored and ways in which the needs of students who report different levels of web enjoyment might be met are discussed

    A novel fluorescent "turn-on" chemosensor for nanomolar detection of Fe(III) from aqueous solution and its application in living cells imaging

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    An electronically active and spectral sensitive fluorescent “turn-on” chemosensor (BTP-1) based on the benzo-thiazolo-pyrimidine unit was designed and synthesized for the highly selective and sensitive detection of FeÂłâș from aqueous medium. With FeÂłâș, the sensor BTP-1 showed a remarkable fluorescence enhancement at 554 nm (λex=314 nm) due to the inhibition of photo-induced electron transfer. The sensor formed a host-guest complex in 1:1 stoichiometry with the detection limit down to 0.74 nM. Further, the sensor was successfully utilized for the qualitative and quantitative intracellular detection of FeÂłâș in two liver cell lines i.e., HepG2 cells (human hepatocellular liver carcinoma cell line) and HL-7701 cells (human normal liver cell line) by a confocal imaging technique

    Ribosomal Proteins RPS11 and RPS20, Two Stress-Response Markers of Glioblastoma Stem Cells, Are Novel Predictors of Poor Prognosis in Glioblastoma Patients.

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    Glioblastoma stem cells (GSC) co-exhibiting a tumor-initiating capacity and a radio-chemoresistant phenotype, are a compelling cell model for explaining tumor recurrence. We have previously characterized patient-derived, treatment-resistant GSC clones (TRGC) that survived radiochemotherapy. Compared to glucose-dependent, treatment-sensitive GSC clones (TSGC), TRGC exhibited reduced glucose dependence that favor the fatty acid oxidation pathway as their energy source. Using comparative genome-wide transcriptome analysis, a series of defense signatures associated with TRGC survival were identified and verified by siRNA-based gene knockdown experiments that led to loss of cell integrity. In this study, we investigate the prognostic value of defense signatures in glioblastoma (GBM) patients using gene expression analysis with Probeset Analyzer (131 GBM) and The Cancer Genome Atlas (TCGA) data, and protein expression with a tissue microarray (50 GBM), yielding the first TRGC-derived prognostic biomarkers for GBM patients. Ribosomal protein S11 (RPS11), RPS20, individually and together, consistently predicted poor survival of newly diagnosed primary GBM tumors when overexpressed at the RNA or protein level [RPS11: Hazard Ratio (HR) = 11.5, p<0.001; RPS20: HR = 4.5, p = 0.03; RPS11+RPS20: HR = 17.99, p = 0.001]. The prognostic significance of RPS11 and RPS20 was further supported by whole tissue section RPS11 immunostaining (27 GBM; HR = 4.05, p = 0.01) and TCGA gene expression data (578 primary GBM; RPS11: HR = 1.19, p = 0.06; RPS20: HR = 1.25, p = 0.02; RPS11+RPS20: HR = 1.43, p = 0.01). Moreover, tumors that exhibited unmethylated O-6-methylguanine-DNA methyltransferase (MGMT) or wild-type isocitrate dehydrogenase 1 (IDH1) were associated with higher RPS11 expression levels [corr (IDH1, RPS11) = 0.64, p = 0.03); [corr (MGMT, RPS11) = 0.52, p = 0.04]. These data indicate that increased expression of RPS11 and RPS20 predicts shorter patient survival. The study also suggests that TRGC are clinically relevant cells that represent resistant tumorigenic clones from patient tumors and that their properties, at least in part, are reflected in poor-prognosis GBM. The screening of TRGC signatures may represent a novel alternative strategy for identifying new prognostic biomarkers
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