Distributed time management in transputer networks

For real-time applications in a distributed system a common notion of time is indispensable. Clocks are used for time measurement, determination of causality, process synchronization and generating unique identifications. All this is only possible if there is a time reference of specified accuracy. Since the local clocks in a distributed system tend to drift away from each other, they need to be adjusted periodically. If the application allows an accuracy that can be met by software, this may be achieved by a distributed clock synchronization algorithm, which creates and maintains a global time reference for all nodes of the network. The design and simulation of such an algorithm for a distributed system consisting of transputers is described. It is based on second order filtered adjustment of the clock rates rather than updating the clock values at onc

Crystallization and preliminary crystallographic data of the PAS domain of the NifL protein from Azotobacter vinelandii.

The Azotobacter vinelandii NifL protein is a redox-sensing flavoprotein which inhibits the activity of the nitrogen-specific transcriptional activator NifA. The N-terminal PAS domain has been overexpressed in Escherichia coli and crystallized by the hanging-drop vapour-diffusion method. The crystal belongs to the rhombohedral space group R32, with unit-cell parameters a = b = 65.0, c = 157.3 Å, and has one molecule in the asymmetric unit. Native data were collected to 3.0 Å on the BW7B synchrotron beamline at the EMBL Hamburg Outstation

Bell's Theorem and Nonlinear Systems

For all Einstein-Podolsky-Rosen-type experiments on deterministic systems the Bell inequality holds, unless non-local interactions exist between certain parts of the setup. Here we show that in nonlinear systems the Bell inequality can be violated by non-local effects that are arbitrarily weak. Then we show that the quantum result of the existing Einstein-Podolsky-Rosen-type experiments can be reproduced within deterministic models that include arbitrarily weak non-local effects.Comment: Accepted for publication in Europhysics Letters. 14 pages, no figures. In the Appendix (not included in the EPL version) the author says what he really thinks about the subjec

Intra- and inter-metabolite correlation spectroscopy of tomato metabolomics data obtained by liquid chromatography-mass spectrometry and nuclear magnetic resonance

Nuclear magnetic resonance (NMR) and liquid chromatography-mass spectrometry (LCMS) are frequently used as technological platforms for metabolomics applications. In this study, the metabolic profiles of ripe fruits from 50 different tomato cultivars, including beef, cherry and round types, were recorded by both 1H NMR and accurate mass LC-quadrupole time-of-flight (QTOF) MS. Different analytical selectivities were found for these both profiling techniques. In fact, NMR and LCMS provided complementary data, as the metabolites detected belong to essentially different metabolic pathways. Yet, upon unsupervised multivariate analysis, both NMR and LCMS datasets revealed a clear segregation of, on the one hand, the cherry tomatoes and, on the other hand, the beef and round tomatoes. Intra-method (NMR¿NMR, LCMS¿LCMS) and inter-method (NMR¿LCMS) correlation analyses were performed enabling the annotation of metabolites from highly correlating metabolite signals. Signals belonging to the same metabolite or to chemically related metabolites are among the highest correlations found. Inter-method correlation analysis produced highly informative and complementary information for the identification of metabolites, even in de case of low abundant NMR signals. The applied approach appears to be a promising strategy in extending the analytical capacities of these metabolomics techniques with regard to the discovery and identification of biomarkers and yet unknown metabolites

Parasitic copepods from Egyptian Red Sea fishes: Bomolochidae Claus, 1875

© The Author(s) 2015 Open Access - This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The attached file is the published version of the article

Trends in hydroidomedusan research from 1911 to 1997

The papers on hydroidomedusae published from 1911 to 1997 total 10,934. They have been assigned to the following categories: faunistics and systematics; sub-organismal biology; ecology; evolution; life cycles; paleontology. The general trend, comprising all papers, can be divided into four time intervals: the first (1911-1939) with an average of sixty papers/year and with a slight decrease due to First World War; the second one (1940-1947), with an average of 38 papers/year, marked by a dramatic decrease coinciding with Second World War; the period 1948-1991 shows a steady increase until the mid-Seventies, when a small decrease occurred, followed by an increasing trend reaching its apex in the late Eighties-early Ninenties with a record of 296 papers in 1991 and with an average of 175 papers/year; the period 1992 1997, with an average of 178 papers/year, is marked by a sharp decrease, reaching the values of the mid Sixties. The most important category in terms of number of papers is sub-organismal biology, followed by faunistics and systematics. Systematic studies dictated the trend in the first decades of the century, whereas sub-organismal ones are prevalent from the Sixties onwards. Faunistic and systematic-taxonomic papers have a steady trend of production, with just a slight decrease over these last years. The formerly leading countries in systematics (UK, USA, France) are now almost inactive in this discipline, whereas countries with little or no tradition in this field (such as Spain) are taking the leadership

Could the Migration of Jupiter Have Accelerated the Atmospheric Evolution of Venus?

In the study of planetary habitability and terrestrial atmospheric evolution, the divergence of surface conditions for Venus and Earth remains an area of active research. Among the intrinsic and external influences on the Venusian climate history are orbital changes due to giant planet migration that have both variable incident flux and tidal heating consequences. Here, we present the results of a study that explores the effect of Jupiter's location on the orbital parameters of Venus and subsequent potential water-loss scenarios. Our dynamical simulations show that various scenarios of Jovian migration could have resulted in orbital eccentricities for Venus as high as 0.31. We quantify the implications of the increased eccentricity, including tidal energy, surface energy flux, and the variable insolation flux expected from the faint young Sun. The tidal circularization timescale calculations demonstrate that a relatively high tidal dissipation factor is required to reduce the eccentricity of Venus to the present value, which implies a high initial water inventory. We further estimate the consequences of high orbital eccentricity on water loss, and estimate that the water-loss rate may have increased by at least ∼5% compared with the circular orbit case as a result of orbital forcing. We argue that these eccentricity variations for the young Venus may have accelerated the atmospheric evolution of Venus toward the inevitable collapse of the atmosphere into a runaway greenhouse state. The presence of giant planets in exoplanetary systems may likewise increase the expected rate of Venus analogs in those systems

Hydrozoa

The European list was derived from URMO which was edited by W. Vervoort. S.D. Cairns provided the list of hydrocorals and P. Schuchert provided additions the list of hydroids