Exponential series without denominators

For a commutative algebra which comes from a Zinbiel algebra the exponential series can be written without denominators. When lifted to dendriform algebras this new series satisfies a functional equation analogous to the Baker-Campbell-Hausdorff formula. We make it explicit by showing that the obstruction series is the sum of the brace products. In the multilinear case we show that the role the Eulerian idempotent is played by the iterated pre-Lie product.Comment: 13

A hazard analysis method for systematic identification of safety requirements for user interface software in medical devices

© Springer International Publishing AG (outside the US) 2017. Formal methods technologies have the potential to verify the usability and safety of user interface (UI) software design in medical devices, enabling significant reductions in use errors and consequential safety incidents with such devices. This however depends on comprehensive and verifiable safety requirements to leverage these techniques for detecting and preventing flaws in UI software that can induce use errors. This paper presents a hazard analysis method that extends Leveson’s System Theoretic Process Analysis (STPA) with a comprehensive set of causal factor categories, so as to provide developers with clear guidelines for systematic identification of use-related hazards associated with medical devices, their causes embedded in UI software design, and safety requirements for mitigating such hazards. The method is evaluated with a case study on the Gantry-2 radiation therapy system, which demonstrates that (1) as compared to standard STPA, our method allowed us to identify more UI software design issues likely to cause use-related hazards; and (2) the identified UI software design issues facilitated the definition of precise, verifiable safety requirements for UI software, which could be readily formalized in verification tools such as Prototype Verification System (PVS).- U.S. Food and Drug Administration(NORTE-01-0145-FEDER-000016)Sandy Weininger (FDA), Scott Thiel (Navigant Consulting, Inc.), Michelle Jump (Stryker), Stefania Gnesi (ISTI/CNR) and the CHI+MED team (www.chi-med.ac.uk) provided useful feedback and inputs. Paolo Masci’s work is supported by the North Portugal Regional Operational Programme (NORTE 2020) under the PORTUGAL 2020 Partnership Agreement, and by the European Regional Development Fund (ERDF) within Project “NORTE-01-0145-FEDER-000016”.info:eu-repo/semantics/publishedVersio

Protein synthesis and transport in the regenerating goldfish visual system

The nature of the proteins synthesized in the goldfish retina and axonally transported to the tectum during optic nerve regeneration has been examined. Electrophoretic analysis of labeled soluble retinal proteins by fluorography verified our previous observation of a greatly enhanced synthesis of the microtubule subunits. In addition, labeling of a tubulin-like protein in the retinal particulate fraction was also increased during regeneration. Like soluble tubulin, the particulate material had an apparent MW of 53–55K and could be tyrosylated in the presence of cycloheximide and [ 3 H]tyrosine. Comparison of post-crush and normal retinal proteins by two-dimensional gel electrophoresis also revealed a marked enhancement in the labeling of two acidic 68–70K proteins. Analysis of proteins slowly transported to the optic tectum revealed changes following nerve crush similar to those observed in the retina, with enhanced labeling of both soluble and particulate tubulin and of 68–70K polypeptides. The most striking change in the profile of rapidly transported protein was the appearance of a labeled 45K protein which was barely detectable in control fish.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45430/1/11064_2004_Article_BF00965529.pd

A (co)homology for restricted Lie algebras

SIGLEAvailable from British Library Document Supply Centre- DSC:DXN054204 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

On the structure of A/k-bialgebras in prime characteristic

In this paper, we study A/k-bialgebras in prime characteristic. Firstly, we prove a Cartier type structure theorem for cocomplete A/k-bialgebras. Secondly, we generalize Michaelis’s theorem. In particular, we prove that a restricted (k, K)-Lie algebra is proper if and only if its restricted enveloping algebra is proper. © 2019, © 2019 Taylor & Francis Group, LLC

Efficiency and productivity of the food and beverage listed firms in the pre-recession and recessionary periods in Greece

This study uses data envelopment analysis to examine the liquidity and sales efficiency of the Food and Beverage listed firms in Athens Exchange in the period 2006–2012. The liquidity efficiency of the firms is higher than the sales efficiency but the results indicate that there are not statistical significant differences in the rankings estimated by the two models in each period. The Malmquist Productivity Index reveals that over the period of the study, firms have experienced an annual average increase in productivity of 0.5% (a slight progress). On examining the components of this productivity change, it becomes evident that firms have experienced an annual average of 2% increase in technology combined with a decrease in technical efficiency of –1.5%. The results indicate that 52.4% of the firms experienced productivity gains in the examined period, and this was mainly the result of technological gain rather than efficiency improvement. More than 90% of the firms in the sample shift the efficiency frontier and only 33.3% of the firms are catching up, improving their productivity by reducing inefficiency. Moreover, the empirical study reveals that the overall technical inefficiencies of the firms are primarily caused by pure technical inefficiencies rather than scale inefficiencies. © 2015, © 2015 Taylor & Francis