15,950 research outputs found

    Comparison of primordial tensor power spectra from the deformed algebra and dressed metric approaches in loop quantum cosmology

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    Loop quantum cosmology tries to capture the main ideas of loop quantum gravity and to apply them to the Universe as a whole. Two main approaches within this framework have been considered to date for the study of cosmological perturbations: the dressed metric approach and the deformed algebra approach. They both have advantages and drawbacks. In this article, we accurately compare their predictions. In particular, we compute the associated primordial tensor power spectra. We show -- numerically and analytically -- that the large scale behavior is similar for both approaches and compatible with the usual prediction of general relativity. The small scale behavior is, the other way round, drastically different. Most importantly, we show that in a range of wavenumbers explicitly calculated, both approaches do agree on predictions that, in addition, differ from standard general relativity and do not depend on unknown parameters. These features of the power spectrum at intermediate scales might constitute a universal loop quantum cosmology prediction that can hopefully lead to observational tests and constraints. We also present a complete analytical study of the background evolution for the bouncing universe that can be used for other purposes.Comment: 15 pages, 7 figure

    Criticality, epistemology and behaviour vs. Design –information systems research across different sets of paradigms

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    Due to its dynamic and rapid development and due to a variety of academic disciplines and research communities contributing to information systems (IS) research, a broad variety of research approaches can be found. These approaches are often discussed as contrasting “paradigms”. Positivism and interpretivism are frequently accepted to be the most relevant paradigms (cf., for instance, Klein & Myers 1999; Lee 1991; Walsham 1995; Weber 2004). A further set of paradigms consists of behavioural science research (‘problem understanding paradigm’) and design science research (‘problem understanding paradigm’) which has been introduced in the IS literature and heavily adopted since (cf., for instance, Hevner et al. 2004; Jani 2001; March & Smith 1995). On top of this distinction, the critical research paradigm, including its logical complement, the non-critical paradigm, shaped the discussion of IS research philosophy for more than two decades (cf., for instance, Brooke 2002; Klein & Huynh 2004; Landry & Banville 1992; Mumford et al. 1985). Though it is essential to research theory and practice in the IS discipline to discuss the interconnections between these different sets of paradigms, such endeavour has not yet been undertaken. Some approaches address the interdependency between interpretivism and critical research. However, a holistic framework, also taking into account also behavioural and design science is still missing. Therefore, the aim of this paper is to provide an integrated discussion of these different sets of paradigms and to provide novel perspectives for IS research on how to deal with the apparent diversity of approaches. We will furthermore point out why this discussion is of great importance to IS research especially in Europe

    Mupirocin Ointment with and without Chlorhexidine Baths in the Eradication of Staphylococcus Aureus Nasal Carriage in Nursing Home Residents

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    Mupirocin ointment has been shown to be effective in eradicating Staphylococcus aureus nasal carriage in residents of a long- term care facility. Antiseptic soaps have been used as adjunct to this therapy. We compared the efficacy of short-term intranasal mupirocin ointment with and without chlorhexidine baths in the eradication of S. aureus nasal carriage with follow-up for 12 weeks. METHODS: Residents in four nursing homes known to have endemic methicillin-resistant S. aureus were screened for nasal carriage of S. aureus. Residents who had anterior nares cultures positive for S. aureus on two separate occasions were divided into two groups. Both groups received intranasal mupirocin ointment twice daily for 5 days and one group also received chlorhexidine baths for the first 3 days. Cultures of anterior nares, axilla, and groins were performed before treatment and 1 day and 1, 4, 8, and 12 weeks after treatment. RESULTS: After treatment, S. aureus nasal carriage was eradicated in all residents. Recolonization with S. aureus had occurred at 12 weeks in 24% of residents receiving mupirocin ointment alone (6/25) and in 15% of residents receiving mupirocin ointment plus chlorhexidine baths (4/27). CONCLUSIONS: A short course of mupirocin ointment was effective in eradicating nasal carriage of S. aureus in nursing home residents. There were no statistical differences in efficacy between the two regimens with respect to the eradication of nasal carriage and prevention of recolonization with S. aureus

    The Pricing Behaviour of Firms in the Euro Area: New Survey Evidence

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    This study investigates the pricing behaviour of firms in the euro area on the basis of surveys conducted by nine Eurosystem national central banks. Overall, more than 11,000 firms participated in the survey. The results are very robust across countries. Firms operate in monopolistically competitive markets, where prices are mostly set following mark-up rules and where price discrimination is a common practice. Our evidence suggests that both time- and state-dependent pricing strategies are applied by firms in the euro area: around one-third of the companies follow mainly time-dependent pricing rules while two-thirds use pricing rules with some element of state-dependence. Although the majority of firms take into account a wide range of information, including past and expected economic developments, about one-third adopts a purely backward-looking behaviour. The pattern of results lends support to the recent wave of estimations of hybrid versions of the New Keynesian Phillips Curve. Price stickiness arises both at the stage when firms review their prices and again when they actually change prices. The most relevant factors underlying price rigidity are customer relationships – as expressed in the theories about explicit and implicit contracts – and thus, are mainly found at the price changing (second) stage of the price adjustment process. Finally, we provide evidence that firms adjust prices asymmetrically in response to shocks, depending on the direction of the adjustment and the source of the shock: while cost shocks have a greater impact when prices have to be raised than when they have to be reduced, reductions in demand are more likely to induce a price change than increases in demand.

    The pricing behaviour of firms in the euro area : new survey evidence

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    This study investigates the pricing behaviour of firms in the euro area on the basis of surveys conducted by nine Eurosystem national central banks. Overall, more than 11,000 firms participated in the survey. The results are very robust across countries. Firms operate in monopolistically competitive markets, where prices are mostly set following mark-up rules and where price discrimination is a common practice. Our evidence suggests that both time- and state-dependent pricing strategies are applied by firms in the euro area: around one-third of the companies follow mainly time-dependent pricing rules while two-thirds use pricing rules with some element of state-dependence. Although the majority of firms take into account a wide range of information, including past and expected economic developments, about one-third adopts a purely backward-looking behaviour. The pattern of results lends support to the recent wave of estimations of hybrid versions of the New Keynesian Phillips Curve. Price stickiness arises both at the stage when firms review their prices and again when they actually change prices. The most relevant factors underlying price rigidity are customer relationships - as expressed in the theories about explicit and implicit contracts - and thus, are mainly found at the price changing (second) stage of the price adjustment process. Finally, we provide evidence that firms adjust prices asymmetrically in response to shocks, depending on the direction of the adjustment and the source of the shock: while cost shocks have a greater impact when prices have to be raised than when they have to be reduced, reductions in demand are more likely to induce a price change than increases in demand.price setting, nominal rigidity, real rigidity, inflation persistence, survey data.

    The efficacy of mupirocin ointment and chlorhexidine body scrubs in the eradication of nasal carriage of Staphylococcus aureus among patients undergoing long-term hemodialysis

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    Patients undergoing long-term hemodialysis have a high prevalence of Staphylococcus aureus nasal carriage, which may lead to serious infections. Mupirocin ointment has been used intranasally to eradicate S. aureus carriage in health human volunteers and health care workers. Chlorhexidine, an antiseptic with excellent antistaphylococcal activity, is widely used for handwashing and skin cleansing. METHODS: Anterior nares cultures were obtained from patients older than 18 years who were undergoing long-term hemodialysis. Patients with S. aureus nasal carriage were enrolled in the study. Axillae and groins were cultured. Patients were given mupirocin ointment intranasally twice per day for 7 days and chlorhexidine body scrubs daily for the first 3 days. Follow-up cultures were obtained from anterior nares, axillae, and groins at 1 day, and 1, 4, 8 and 12 weeks after treatment. RESULTS: One day after completion of treatment nasal carriage was eradicated in 83% of patients (15/18). After 12 weeks, 69% of patients (11/16) were free of nasal carriage. CONCLUSIONS: Success rates of eradication were excellent compared with those in other published reports. This simple and effective regimen had no major side effect

    Acculturation, coping, and integration success of international skilled migrants: An integrative review and multilevel framework

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    In this article, we review the limited but growing body of research on international skilled migrants and examine to what extent knowledge generated in adjacent research streams-specifically, work on assigned and self-initiated expatriates-can be meaningfully applied to aid our under- standing of the challenges, coping strategies, and acculturation dynamics of skilled migrants. We develop a framework that explains how variables and processes at multiple levels (individual, organisational, and societal) influence migrant acculturation and coping and result in integration-related outcomes in the domains of personal/family life and workplace/career. We discuss directions for future research and implications for practice

    Community structure of a microbial mat: the phylogenetic dimension.

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    Long-term spectroscopic monitoring of the Luminous Blue Variable HD160529

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    We have spectroscopically monitored the galactic Luminous Blue Variable HD 160529 and obtained an extensive high-resolution data set that covers the years 1991 to 2002. During this period, the star evolved from an extended photometric minimum phase towards a new visual maximum. In several observing seasons, we covered up to four months with almost daily spectra. Our spectra typically cover most of the visual spectral range with a high spectral resolution (about 20,000 or more). This allows us to investigate the variability in many lines and on many time scales from days to years. We find a correlation between the photospheric HeI lines and the brightness of the star, both on a time scale of months and on a time scale of years. The short-term variations are smaller and do not follow the long-term trend, strongly suggesting different physical mechanisms. Metal lines also show both short-term and long-term variations in strength and also a long-term trend in radial velocity. Most of the line-profile variations can be attributed to changing strengths of lines. Propagating features in the line profiles are rarely observed. We find that the mass-loss rate of HD 160529 is almost independent of temperature, i.e. visual brightness.Comment: 14 pages, 15 figures, accepted for publication in Astronomy & Astrophysic

    Cross Validation of a Figure Skating Blade Instrumented to Measure Figure Skating Impact

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    Please refer to the pdf version of the abstract located adjacent to the title
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