411,353 research outputs found

    Matching Kasteleyn Cities for Spin Glass Ground States

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    As spin glass materials have extremely slow dynamics, devious numerical methods are needed to study low-temperature states. A simple and fast optimization version of the classical Kasteleyn treatment of the Ising model is described and applied to two-dimensional Ising spin glasses. The algorithm combines the Pfaffian and matching approaches to directly strip droplet excitations from an excited state. Extended ground states in Ising spin glasses on a torus, which are optimized over all boundary conditions, are used to compute precise values for ground state energy densities.Comment: 4 pages, 2 figures; minor clarification

    Decision aids for people facing health treatment or screening decisions (Review)

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    Background Decision aids prepare people to participate in ’close call’ decisions that involve weighing benefits, harms, and scientific uncertainty. Objectives To conduct a systematic review of randomised controlled trials (RCTs) evaluating the efficacy of decision aids for people facing difficult treatment or screening decisions. Search strategy We searched MEDLINE (Ovid) (1966 to July 2006); Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library; 2006, Issue 2); CINAHL (Ovid) (1982 to July 2006); EMBASE (Ovid) (1980 to July 2006); and PsycINFO (Ovid) (1806 to July 2006). We contacted researchers active in the field up to December 2006. There were no language restrictions. Selection criteria We included published RCTs of interventions designed to aid patients’ decision making by providing information about treatment or screening options and their associated outcomes, compared to no intervention, usual care, and alternate interventions. We excluded studies in which participants were not making an active treatment or screening decision, or if the study’s intervention was not available to determine that it met the minimum criteria to qualify as a patient decision aid. Data collection and analysis Two review authors independently screened abstracts for inclusion, and extracted data from included studies using standardized forms. The primary outcomes focused on the effectiveness criteria of the International Patient Decision Aid Standards (IPDAS) Collaboration: attributes of the decision and attributes of the decision process. We considered other behavioural, health, and health system effects as secondary outcomes. We pooled results of RCTs using mean differences (MD) and relative risks (RR) using a random effects model. Main results This update added 25 new RCTs, bringing the total to 55. Thirty-eight (69%) used at least one measure that mapped onto an IPDAS effectiveness criterion: decision attributes: knowledge scores (27 trials); accurate risk perceptions (11 trials); and value congruence with chosen option (4 trials); and decision process attributes: feeling informed (15 trials) and feeling clear about values (13 trials). This review confirmed the following findings from the previous (2003) review. Decision aids performed better than usual care interventions in terms of: a) greater knowledge (MD 15.2 out of 100; 95% CI 11.7 to 18.7); b) lower decisional conflict related to feeling uninformed (MD -8.3 of 100; 95% CI -11.9 to -4.8); c) lower decisional conflict related to feeling unclear about personal values (MD -6.4; 95% CI -10.0 to -2.7); d) reduced the proportion of people who were passive in decision making (RR 0.6; 95% CI 0.5 to 0.8); and e) reduced proportion of people who remained undecided post-intervention (RR 0.5; 95% CI 0.3 to 0.8). When simpler decision aids were compared to more detailed decision aids, the relative improvement was significant in knowledge (MD 4.6 out of 100; 95% CI 3.0 to 6.2) and there was some evidence of greater agreement between values and choice. In this review, we were able to explore the use of probabilities in decision aids. Exposure to a decision aid with probabilities resulted in a higher proportion of people with accurate risk perceptions (RR 1.6; 95% CI 1.4 to 1.9). The effect was stronger when probabilities were measured quantitatively (RR 1.8; 95% CI 1.4 to 2.3) versus qualitatively (RR 1.3; 95% CI 1.1 to 1.5). As in the previous review, exposure to decision aids continued to demonstrate reduced rates of: elective invasive surgery in favour of conservative options, decision aid versus usual care (RR 0.8; 95% CI 0.6 to 0.9); and use of menopausal hormones, detailed versus simple aid (RR 0.7; 95% CI 0.6 to 1.0). There is now evidence that exposure to decision aids results in reduced PSA screening, decision aid versus usual care (RR 0.8; 95% CI 0.7 to 1.0) . For other decisions, the effect on decisions remains variable. As in the previous review, decision aids are no better than comparisons in affecting satisfaction with decision making, anxiety, and health outcomes. The effects of decision aids on other outcomes (patient-practitioner communication, consultation length, continuance, resource use) were inconclusive. There were no trials evaluating the IPDAS decision process criteria relating to helping patients to recognize a decision needs to be made, understand that values affect the decision, or discuss values with the practitioner. Authors’ conclusions Patient decision aids increase people’s involvement and are more likely to lead to informed values-based decisions; however, the size of the effect varies across studies. Decision aids have a variable effect on decisions. They reduce the use of discretionary surgery without apparent adverse effects on health outcomes or satisfaction. The degree of detail patient decision aids require for positive effects on decision quality should be explored. The effects on continuance with chosen option, patient-practitioner communication, consultation length, and cost-effectiveness need further evaluation. This review is published as a Cochrane Review in the Cochrane Database of Systematic Reviews 2009, Issue 3. Cochrane Reviews are regularly updated as new evidence emerges and in response to comments and criticisms, and the Cochrane Database of Systematic Reviews should be consulted for the most recent version of the Review.</p

    Clarification Of Aqueous Suspensions With A High Content Of Suspended Solids In Rapid Sand Filters

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    The presented work is devoted to solving the actual problem of increasing the efficiency of rapid sand filters with granular filling, which operate at a constant filtration rate when cleaning suspensions with a relatively high concentration of contaminants. The proposed mathematical model for clarifying the suspension by filtration consists of three interconnected blocks: clarified, filtration, and hydraulic. Convenient dimensionless mathematical dependencies are obtained for calculating the concentrations of contaminants and sediment from the height of the filter and suspension in the filtrate; head loss in the filter loading; the effective time of the filter (the duration of the filter cycle). The design of the experimental setup and the methodology for conducting experimental studies and mathematical processing of the results are valid. The results of experimental studies of the suspension filtering process through the granular loading are presented, and the obtained data is analyzed. Measurement of pressure losses in the filter loading is performed when a suspension is passed with a relatively high concentration of contaminants at various filtration rates. The nature of the change in the filtration rate with time and height (length) loading at various filtration rates and initial contamination concentrations is determined. Measured variable concentration of suspended matter in filtered water and retained contamination over time. As a result of the experiments, it is confirmed that an increase in the concentration of retained contaminants S leads to an increase in the parameter Δn/n. Upon reaching a certain value of the concentration of the retained sediment S (in our case S=30 g/dm3), an increase in the relative specific volume of the sediment greater than Δn/n0=0.65 is not observed. It is established that an important characteristic of the retained sediment is the ratio of the volume concentration of the sediment to the volume concentration of solid particles in this sediment γ=Csd/Сs. The values of the adhesion and detachment of particles of contaminant in the particles of the material loading =4,9; =0,009. The results of experimental studies in general confirm the correctness and reliability of the obtained analytical dependencies

    Eltrombopag for the treatment of chronic idiopathic (immune) thrombocytopenic purpura : A Single Technology Appraisal

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    Evidence Review Group (ERG) final report for the National Institute for Health and Clinical ExcellencePublisher PD

    Identifying Unclear Questions in Community Question Answering Websites

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    Thousands of complex natural language questions are submitted to community question answering websites on a daily basis, rendering them as one of the most important information sources these days. However, oftentimes submitted questions are unclear and cannot be answered without further clarification questions by expert community members. This study is the first to investigate the complex task of classifying a question as clear or unclear, i.e., if it requires further clarification. We construct a novel dataset and propose a classification approach that is based on the notion of similar questions. This approach is compared to state-of-the-art text classification baselines. Our main finding is that the similar questions approach is a viable alternative that can be used as a stepping stone towards the development of supportive user interfaces for question formulation.Comment: Proceedings of the 41th European Conference on Information Retrieval (ECIR '19), 201

    Vaccine Epidemiology and Decision-Making: A Bryant Student Focus

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    The Centers for Disease Control and Prevention estimate that influenza has resulted in between 9.2 and 35.6 million illnesses and between 12,000 and 56,000 deaths annually since 2010 (1). Annual influenza vaccination remains to be the most effective way in controlling the spread and symptom severity of influenza infections (1). Influenza infections are especially virulent on college campuses as a dense population of students interact in close quarters such as shared housing, bathrooms, dining halls, classrooms, and social activities (2). Despite influenza vaccinations being safe, effective, easily accessible to Bryant University students, and free of cost, many students choose not to receive an annual vaccination. A survey and interviews were conducted among Bryant University students to: determine the vaccination rate of students on campus; determine reasons why students did or did not decide to receive this season’s flu vaccination; and analyze how the vaccination rates and decision-making of students affect the overall health of the Bryant University campus. Based on the survey data, only 25.15% of Bryant University students participating in the survey had received a vaccination this year, and only a small fraction of these individuals were vaccinated at the Health Services clinics. This incredibly low vaccination rate among the Bryant University student body has severe consequences for the students, University, healthcare system, and even the surrounding communities. This research discusses the importance of vaccination, impact of influenza on Bryant students’ health, the reasons for the low vaccination rate on campus, and describes potential ways to enhance student participation in on-campus vaccination clinics

    Performance evaluation on optimisation of 200 dimensional numerical tests - results and issues

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    Abstract: Many tasks in science and technology require optimisation. Resolving such tasks could bring great benefits to community. Multidimensional problems where optimisation parameters are hundreds and more face unusual computational limitations. Algorithms, which perform well on low number of dimensions, when are applied to high dimensional space suffers insuperable difficulties. This article presents an investigation on 200 dimensional scalable, heterogeneous, real-value, numerical tests. For some of these tests optimal values are dependent on dimensions’ number and virtually unknown for variety of dimensions. Dependence on initialisation for successful identification of optimal values is analysed by comparison between experiments with start from random initial locations and start from one location. The aim is to: (1) assess dependence on initialisation in optimisation of 200 dimensional tests; (2) evaluate tests complexity and required for their resolving periods of time; (3) analyse adaptation to tasks with unknown solutions; (4) identify specific peculiarities which could support the performance on high dimensions (5) identify computational limitations which numerical methods could face on high dimensions. Presented and analysed experimental results can be used for further comparison and evaluation of real value methods

    Accountability and Moral Competence Promote Ethical Leadership

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    Accountability and moral competence are two factors that may have a positive effect on ethical leadership in organizations. This study utilized a survey methodology to investigate the relationship among accountability, moral competence and ethical leadership in a sample of 103 leaders from a variety of industries and different countries. Accountability was found to be a significant positive predictor of ethical leadership. Moral competence was also found to moderate this relationship such that increases in moral competence enhanced the positive effects of accountability on ethical leadership. The results of the study suggest that organizations can increase ethical leadership throughout the company via accountability (especially self-accountability) and moral competence by training their leaders to use self-monitoring behaviors and increasing moral education

    Title X Parental Notification Regulation - A Different Prognosis

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    Evaluation of the Physical Stability of Zinc Oxide Suspensions Containing Sodium Poly-(acrylate) and Sodium Dodecylsulfate.

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    The physical stability of zinc oxide (ZnO) aqueous suspensions has been monitored during two months by different methods of investigation. The suspensions were formulated with ZnO at a fixed concentration (5 wt%), sodium poly-(acrylate), as a viscosifier, and sodium dodecylsulfate (SDS), as a wetting agent. The rheological study shows that the suspensions exhibit a non-Newtonian, most often shear-thinning behavior and their apparent viscosity increases with polymer concentration. The rheograms of most of the ZnO suspensions do not vary during the experimental period. The viscoelastic properties of these suspensions, such as elastic or storage modulus (G′), viscous or loss modulus (G″) and phase angle (δ) were also examined. For% strains lower than 10%, all the formulations show strong elastic properties (G′ > G″, δ varies between 5 and 15°). Beyond 10% strain, the rheological behavior changes progressively from elastic to viscous (G″ > G′ for % strain >80%). Consistently, δ increases and reaches the 50–70° zone. Multiple light scattering (back-scattered intensity), measured with the Turbiscan ags, was used to characterize suspension physical stability (early detection of particle or aggregate size variations and particle/aggregate migration phenomena). Suspensions containing 0.4 and 0.6 wt% polymer remain stable and macroscopically homogeneous, without being affected by the change of particle size observed with a laser particle sizer. Sedimentation tests, pH, and ζ potential measurements versus time, also confirmed these findings
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