177 research outputs found

    On sequential fixed-width confidence intervals for the mean and second-order expansions of the associated coverage probabilities

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    In order to construct fixed-width (2d) confidence intervals for the mean of an unknown distribution function F , a new purely sequential sampling strategy is proposed first. The approach is quite different from the more traditional methodology of Chow and Robbins (1965, Ann. Math. Statist. , 36 , 457–462). However, for this new procedure, the coverage probability is shown (Theorem 2.1) to be at least (1-α)+ Ad 2 + o (d 2 ) as d →0 where (1-α) is the preassigned level of confidence and A is an appropriate functional of F , under some regularity conditions on F . The rates of convergence of the coverage probability to (1-α) obtained by Csenki (1980, Scand. Actuar. J. , 107–111) and Mukhopadhyay (1981, Comm. Statist. Theory Methods , 10 , 2231–2244) were merely O (d 1/2-q ), with 0< q <1/2, under the Chow-Robbins stopping time τ * . It is to be noted that such considerable sharpening of the rate of convergence of the coverage probability is achieved even though the new stopping variable is O p (τ * ). An accelerated version of the stopping rule is also provided together with the analogous second-order characteristics. In the end, an example is given for the mean estimation problem of an exponential distribution.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47956/1/10463_2004_Article_BF00050850.pd

    A Greater Means to the Greater Good: Ethical Guidelines to Meet Social Movement Organization Advocacy Challenges

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    Existing public relations ethics literature often proves inadequate when applied to social movement campaigns, considering the special communication challenges activists face as marginalized moral visionaries in a commercial public sphere. The communications of counter-hegemonic movements is distinct enough from corporate, nonprofit, and governmental organizations to warrant its own ethical guidelines. The unique communication guidelines most relevant to social movement organizations include promoting asymmetrical advocacy to a greater extent than is required for more powerful organizations and building flexibility into the TARES principles to privilege social responsibility over respect for audience values in activist campaigns serving as ideological critique

    Spreading continents kick-started plate tectonics

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    International audienceStresses acting on cold, thick and negatively buoyant oceanic litho- sphere are thought to be crucial to the initiation of subduction and the operation of plate tectonics, which characterizes the present- day geodynamics of the Earth. Because the Earth’s interior was hotter in the Archaean eon, the oceanic crust may have been thicker, thereby making the oceanic lithosphere more buoyant than at present, and whether subduction and plate tectonics occurred during this time is ambiguous, both in the geological record and in geodynamic models. Here we show that because the oceanic crust was thick and buoyant5, early continents may have produced intra-lithospheric gravitational stresses large enough to drive their gravitational spreading, to initiate subduction at their margins and to trigger episodes of subduction. Our model predicts the co-occurrence of deep to progressively shallower mafic volcanics and arc magmatism within continents in a self-consistent geodynamic framework, explaining the enigmatic multimodal volcanism and tectonic record of Archaean cratons. Moreover, our model predicts a petrological stratification and tectonic structure of the sub-continental lithospheric mantle, two predictions that are consistent with xenolith and seismic studies, respectively, and consistent with the existence of a mid-lithospheric seismic discontinuity. The slow gravitational collapse of early continents could have kick-started transient episodes of plate tectonics until, as the Earth’s interior cooled and oceanic lithosphere became heavier, plate tectonics became self-sustaining

    Impact of the Mitochondrial Genetic Background in Complex III Deficiency

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    BACKGROUND: In recent years clinical evidence has emphasized the importance of the mtDNA genetic background that hosts a primary pathogenic mutation in the clinical expression of mitochondrial disorders, but little experimental confirmation has been provided. We have analyzed the pathogenic role of a novel homoplasmic mutation (m.15533 A>G) in the cytochrome b (MT-CYB) gene in a patient presenting with lactic acidosis, seizures, mild mental delay, and behaviour abnormalities. METHODOLOGY: Spectrophotometric analyses of the respiratory chain enzyme activities were performed in different tissues, the whole muscle mitochondrial DNA of the patient was sequenced, and the novel mutation was confirmed by PCR-RFLP. Transmitochondrial cybrids were constructed to confirm the pathogenicity of the mutation, and assembly/stability studies were carried out in fibroblasts and cybrids by means of mitochondrial translation inhibition in combination with blue native gel electrophoresis. PRINCIPAL FINDINGS: Biochemical analyses revealed a decrease in respiratory chain complex III activity in patient's skeletal muscle, and a combined enzyme defect of complexes III and IV in fibroblasts. Mutant transmitochondrial cybrids restored normal enzyme activities and steady-state protein levels, the mutation was mildly conserved along evolution, and the proband's mother and maternal aunt, both clinically unaffected, also harboured the homoplasmic mutation. These data suggested a nuclear genetic origin of the disease. However, by forcing the de novo functioning of the OXPHOS system, a severe delay in the biogenesis of the respiratory chain complexes was observed in the mutants, which demonstrated a direct functional effect of the mitochondrial genetic background. CONCLUSIONS: Our results point to possible pitfalls in the detection of pathogenic mitochondrial mutations, and highlight the role of the genetic mtDNA background in the development of mitochondrial disorders

    Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

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    BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London

    Research Methodologies and Business Discourse Teaching

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    This chapter will:; ; ; Define English for specific purposes and indicate the specific ways in which it has been influential on business discourse teaching;; ; ; Discuss the most relevant approaches to genre analysis that have been used in business discourse teaching;; ; ; Explore the most relevant approaches to critical discourse analysis and organizational rhetoric for business discourse teaching;; ; ; Identify the most relevant aspects of multimodal discourse analysis for business discourse teaching;; ; ; Provide a case study that illustrates the use of one approach to business discourse teaching, showing how practitioners can incorporate it into their classroom- or consultancy-based ideas

    Can physical education and physical activity outcomes be developed simultaneously using a game-centered approach?

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    The primary objective of this study was to evaluate the efficacy of a pilot intervention using a gamecentered approach for improvement of physical activity (PA) and physical education (PE) outcomes simultaneously, and if this had an impact on enjoyment of PE. A group-randomized controlled trial with a 7-week wait-list control group was conducted in one primary school in the Hunter Region, NSW, Australia. Participants (n = 107 students; mean age = 10.7 years, SD 0.87) were randomized by class group into the Professional Learning for Understanding Games Education (PLUNGE) pilot intervention (n = 52 students) or the control (n = 55) conditions. PLUNGE involved 6 x 60 min PE lessons based on game-centered curriculum delivered via an in-class teacher mentoring program. Students were assessed at baseline and 7-week follow-up for fundamental movement skills (FMS) of throw and catch, game play abilities of decision making, support and skill performance; in-class PA; and enjoyment of PA. Linear mixed models revealed significant group-by-time intervention effects (p < 0.05) for throw (effect size: d = 0.9) and catch (d = 0.4) FMS, decision making (d = 0.7) and support (d = 0.9) during game play, and in-class PA (d = 1.6). No significant intervention effects (p > 0.05) were observed for skills outcome during game play (d = -0.2) or student enjoyment (d = 0.1). Game-centered pedagogy delivered via a teacher professional learning program was efficacious in simultaneously improving students' FMS skills, in-class PA and their decision making and support skills in game play
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