Viewpoint consistency in Z and LOTOS: A case study

Specification by viewpoints is advocated as a suitable method of specifying complex systems. Each viewpoint describes the envisaged system from a particular perspective, using concepts and specification languages best suited for that perspective. Inherent in any viewpoint approach is the need to check or manage the consistency of viewpoints and to show that the different viewpoints do not impose contradictory requirements. In previous work we have described a range of techniques for consistency checking, refinement, and translation between viewpoint specifications, in particular for the languages LOTOS and Z. These two languages are advocated in a particular viewpoint model, viz. that of the Open Distributed Processing (ODP) reference model. In this paper we present a case study which demonstrates how all these techniques can be combined in order to show consistency between a viewpoint specified in LOTOS and one specified in Z. Keywords: Viewpoints; Consistency; Z; LOTOS; ODP

Peripherally Inserted Central Catheters vs Peripheral Cannulas for Delivering Parenteral Nutrition in Neonates

CLINICAL QUESTION: Is parenteral nutrition via peripherally inserted central catheters (PICCs) associated with better delivery of nutrition and growth and fewer adverse events compared with short peripheral cannulas in neonates? BOTTOM LINE: Compared with short peripheral cannulas, parenteral nutrition via PICCs is associated with better nutrient delivery and lower rates of subsequent catheters or cannulas placed and is not associated with increased rates of invasive infection

On the Change in Archivability of Websites Over Time

As web technologies evolve, web archivists work to keep up so that our digital history is preserved. Recent advances in web technologies have introduced client-side executed scripts that load data without a referential identifier or that require user interaction (e.g., content loading when the page has scrolled). These advances have made automating methods for capturing web pages more difficult. Because of the evolving schemes of publishing web pages along with the progressive capability of web preservation tools, the archivability of pages on the web has varied over time. In this paper we show that the archivability of a web page can be deduced from the type of page being archived, which aligns with that page's accessibility in respect to dynamic content. We show concrete examples of when these technologies were introduced by referencing mementos of pages that have persisted through a long evolution of available technologies. Identifying these reasons for the inability of these web pages to be archived in the past in respect to accessibility serves as a guide for ensuring that content that has longevity is published using good practice methods that make it available for preservation.Comment: 12 pages, 8 figures, Theory and Practice of Digital Libraries (TPDL) 2013, Valletta, Malt

Taking Bitcoin to the stockmarket won’t do much for its risky image

Since its inception in 2008 digital currency Bitcoin has attracted critics who argue it’s inherently risky. The latest push to create an exchange traded fund (ETF) in order to make trading it easier, suggests attitudes to it haven’t changed. But some risks associated with a Bitcoin ETF is just like any other asset that becomes tied to investors and the stockmarket. The US Securities and Exchange Commission (SEC) has already rejected an application to create an ETF for Bitcoin. But there are two other proposals - (SolidX & Grayscale) still before the commission. Bitcoin is intended to act like currency in that, once you have a Bitcoin, you can use it to buy goods. It’s much the same as using electronic payments from a bank. Like a currency too, it has its own exchange rate and can be traded for other currencies. It has a history of wild price fluctuations as investors have in turns bought it with enthusiasm and sold it when spooked. The push for Bitcoin ETFs is not only the result of more and more money flowing into these funds, but also because ETFs make it much easier to invest in types of non-traditional assets like Bitcoin

Are we choosing the right flagships? The bird species and traits Australians find most attractive

Understanding what people like about birds can help target advocacy for bird conservation. However, testing preferences for characteristics of birds is methodologically challenging, with bias difficult to avoid. In this paper we test whether preferred characteristics of birds in general are shared by the individual bird species the same people nominate as being those they consider most attractive. We then compare these results with the birds which appear most frequently in the imagery of conservation advocates. Based on a choice model completed by 638 general public respondents from around Australia, we found a preference for small colourful birds with a melodious call. However, when the same people were asked which five birds they found most attractive, 48% named no more than three, mostly large well-known species. Images displayed by a leading Australian bird conservation organisation also favoured large colourful species. The choice model results suggest conservation advocates can promote a much wider range of bird types as flagships, particularly smaller species that might otherwise be neglected

A new technique for transumbilical insertion of central venous silicone catheters in newborn infants

Aim: A new technique allowing placement of umbilical silicone venous catheters (USVC) is described and compared with percutaneous silicone venous catheters (PSVC)

Cytoplasmic localization of Hug1p, a negative regulator of the MEC1 pathway, coincides with the compartmentalization of Rnr2p-Rnr4p

The evolutionarily conserved MEC1 checkpoint pathway mediates cell cycle arrest and induction of genes including the RNR (Ribonucleotide reductase) genes and HUG1 (Hydroxyurea, ultraviolet, and gamma radiation) in response to DNA damage and replication arrest. Rnr complex activity is in part controlled by cytoplasmic localization of the Rnr2p-Rnr4p subunits and inactivation of negative regulators Sml1p and Dif1p upon DNA damage and hydroxyurea (HU) treatment. We previously showed that a deletion of HUG1 rescues lethality of mec1 Delta and suppresses dun1 Delta strains. In this study, multiple approaches demonstrate the regulatory response of Hug1p to DNA damage and HU treatment and support its role as a negative effector of the MEC1 pathway. Consistent with our hypothesis, wild-type cells are sensitive to DNA damage and HU when HUG1 is overexpressed. A Hug1 polyclonal antiserum reveals that HUG1 encodes a protein in budding yeast and its MEC1-dependent expression is delayed compared to the rapid induction of Rnr3p in response to HU treatment. Cell biology and subcellular fractionation experiments show localization of Hug1p-GFP to the cytoplasm upon HU treatment. The cytoplasmic localization of Hug1p-GFP is dependent on MEC1 pathway genes and coincides with the cytoplasmic localization of Rnr2p-Rnr4p. Taken together, the genetic interactions, gene expression, and localization studies support a novel role for Hug1p as a negative regulator of the MEC1 checkpoint response through its compartmentalization with Rnr2p-Rnr4p. Published by Elsevier Inc