58 research outputs found

    Solar System Abundances of the Elements

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    Representative abundances of the chemical elements for use as a solar abundance standard in astronomical and planetary studies are summarized. Updated abundance tables for solar system abundances based on meteorites and photospheric measurements are presented.Comment: 46 pages; 5 figures; 8 tables; In: Principles and Perspectives in Cosmochemistry.Lecture Notes of the Kodai School on 'Synthesis of Elements in Stars' held at Kodaikanal Observatory, India, April 29 - May 13, 2008 (Aruna Goswami and B. Eswar Reddy eds.) Astrophysics and Space Science Proceedings, Springer-Verlag Berlin Heidelberg, 2010, p. 379-417 (ISBN 978-3-642-10351-3), 201

    Interleukin-6 Receptor Antagonists in Critically Ill Patients with Covid-19.

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    BACKGROUND: The efficacy of interleukin-6 receptor antagonists in critically ill patients with coronavirus disease 2019 (Covid-19) is unclear. METHODS: We evaluated tocilizumab and sarilumab in an ongoing international, multifactorial, adaptive platform trial. Adult patients with Covid-19, within 24 hours after starting organ support in the intensive care unit (ICU), were randomly assigned to receive tocilizumab (8 mg per kilogram of body weight), sarilumab (400 mg), or standard care (control). The primary outcome was respiratory and cardiovascular organ support-free days, on an ordinal scale combining in-hospital death (assigned a value of -1) and days free of organ support to day 21. The trial uses a Bayesian statistical model with predefined criteria for superiority, efficacy, equivalence, or futility. An odds ratio greater than 1 represented improved survival, more organ support-free days, or both. RESULTS: Both tocilizumab and sarilumab met the predefined criteria for efficacy. At that time, 353 patients had been assigned to tocilizumab, 48 to sarilumab, and 402 to control. The median number of organ support-free days was 10 (interquartile range, -1 to 16) in the tocilizumab group, 11 (interquartile range, 0 to 16) in the sarilumab group, and 0 (interquartile range, -1 to 15) in the control group. The median adjusted cumulative odds ratios were 1.64 (95% credible interval, 1.25 to 2.14) for tocilizumab and 1.76 (95% credible interval, 1.17 to 2.91) for sarilumab as compared with control, yielding posterior probabilities of superiority to control of more than 99.9% and of 99.5%, respectively. An analysis of 90-day survival showed improved survival in the pooled interleukin-6 receptor antagonist groups, yielding a hazard ratio for the comparison with the control group of 1.61 (95% credible interval, 1.25 to 2.08) and a posterior probability of superiority of more than 99.9%. All secondary analyses supported efficacy of these interleukin-6 receptor antagonists. CONCLUSIONS: In critically ill patients with Covid-19 receiving organ support in ICUs, treatment with the interleukin-6 receptor antagonists tocilizumab and sarilumab improved outcomes, including survival. (REMAP-CAP ClinicalTrials.gov number, NCT02735707.)

    Competitive Weighted Matching

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    Consider a bipartite graph with a set of left-vertices and a set of right-vertices. All the edges adjacent to the same left-vertex have the same weight. We present an algorithm that, given the set of right-vertices and the number of left-vertices, processes a uniformly random permutation of the left-vertices, one left-vertex at a time. In processing a particular left-vertex, the algorithm either permanently matches the left-vertex to a thus-far unmatched right-vertex, or decides never to match the left-vertex. The weight of the matching returned by our algorithm is within a constant factor of that of a maximum weight matching, generalizing the recent results of Babaioff et al

    Resource Advantage Theory and Fair Trade Social Enterprises

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    This paper will investigate the competitive position of both fair trade (FT) social enterprises Divine Chocolate Ltd (Divine) and Cafédirect in their respective UK markets, namely chocolate confectionery and hot beverages. Using Eisenhardt’s (1989, 1991, and 2007) approach to building theory from multiple case studies, this four-year PhD study aims to identify the resources that enable FT social enterprises to compete. This research draws on recent developments in competition theory such as resource advantage theory (R-A theory), termed a general theory of competition. The paper will critically analyse if the social and ethical elements of these firm’s product offerings really constitute meaningful differentiators (i.e. comparative advantage) as required by R-A theory (Hunt and Morgan 1995, Hunt 2001). Hunt and Derozier (2004) argue that R-A theory can ground theories of business and marketing strategy and therefore identifying the competitive resources of FT social enterprises will have important strategic implications. The research findings show that both Divine and Cafédirect have established a mainstream competitive position in specific product segments and distribution channels. Thus illustrating intra-industry demand to be heterogeneous. In addition, both companies have been a catalyst for change by influencing the strategies and policies of both branded manufactures and retailers such as Cooperative Food (CF). The key theoretical contribution validates ‘social resources’ and its three inter-related components: ethical and social commitments, connections with partners and consistency of behaviour as a resource to extend R-A theory. These ‘social resources’ in combination with both relational resources and threshold capabilities (e.g. product quality) result in a competitive position for both case organisations. The ethical and social commitments of ‘social resources’ also appears to provide an example of an ethical underpinning to Relationship Marketing. The identification of ‘social resources’ has important wider implications for both other social enterprises and those companies who are aiming to achieve a competitive position based on social commitments
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