Release of noble gases and nitrogen from grain-surface sites in lunar ilmenite by closed-system oxidation

Noble gases and nitrogen were extracted from a 100 to 150 microns ilmenite separate from lunar soil 71501 by closed system stepped heating in approx. 10 torr O2 at 300 C, 400 C, 500 C, 600 C and 630 C, followed by stepped pyrolysis at ten temperatures between 680 C and approx. 1500 C. The five oxidation steps together liberated approx. 65% of the total He-4, 45% of the Ne-20, 23% of the N-14 and Ar-36, 12% of the Kr-84 and 8% of the Xe-132 in the sample; Ne-20/Ar-36 and Ne-20/Ne-22 ratios agree with the solar wind composition experiment, and Kr-84/Ar-36 and Xe-132/Ar-36 are within approx. 10% of Cameron's estimates for the sun and solar wind. The remaining gases, released above 630 C by pyrolysis, are strongly fractionated with respect to the SWC-Cameron solar wind elemental composition. Large concentrations of fractionated noble gases in grain interiors, their virtual absence in the relatively unfractionated surface gas reservoir, and the high N/noble gas ratio all imply that most of the solar wind noble gases initially implanted in grain surfaces are eventually lost by diffusion. Loss limits can be estimated by considering two given scenarios. It is concluded tat approx. 70 to 97% or more of the Ar implanted in 71501 ilmenite grains has diffusively escaped

EVALUATION OF SPEED-TESTS FOR PLAYERS OF SPORT GAMES

PROBLEM. The characteristics demands of the load of the common sport games are different, but many similarities are obvious. 'They all require a high ability of anticipation. reaction- and action speed. Many actions like dribbling, feint. tracing and attacking adversary are carried out with highest intensity (speed) in combination with rapid changes in direction of motion In split seconds decisions between alternative movements must be reached and go into action. The available speed tests were not able to satis6 these requirements (e.g. 1, 2). The aim of this study was to evaluate tests for speed-diagnostics. which consider the specific demands of the sport games soccer, handball, tennis. MEI'HODS The length of the run and the kind of changes of direction depends on the conditions of the sport game For the time recording we used a measuring system of 4 double lightbars Each run starts from a defined position on a contact platform. The starts were free selected and/or given by an optical signal. The following abilities here recorded differently in separate tests: 4 the ability to start and accelerate straight on. I3 the ability to start. decelerate. accelerate in connection with changes in direction of motion the ability to react in connection \kith selection and following game specific movement. calculated by test-retest correlation coefficient To check the selectivity of the tests analysis of variance were used to calculate significant differences. KESliL.T.5 - the reliability of the evaluated tests are in the range of rtt = 72 - .98. and therefore altogether acceptable - the selectivity of the tests is also acceptable in general ( exception. test .4 for Tennis plavers). - the great intraindividuell differences between runners with turns to the left and right. as well as between the players within a team illustrate the necessarity from precise diagnostics A few number of training sessions will eliminate individual deficit

Multiple-scattering effects on incoherent neutron scattering in glasses and viscous liquids

Incoherent neutron scattering experiments are simulated for simple dynamic models: a glass (with a smooth distribution of harmonic vibrations) and a viscous liquid (described by schematic mode-coupling equations). In most situations multiple scattering has little influence upon spectral distributions, but it completely distorts the wavenumber-dependent amplitudes. This explains an anomaly observed in recent experiments

A note on shell models for MHD Turbulence

We investigate the time evolution of two different (GOY-like) shell models which have been recently proposed to describe the gross features of MHD turbulence. We see that, even if they are formally of the same type sharing with MHD equations quadratic couplings and similar conserved quantities, fundamental differences exist which are related to the ideal invariants.Comment: 6 pages, 5 figures.eps, to appear in Europhysics Letter

A Sparse Stress Model

Force-directed layout methods constitute the most common approach to draw general graphs. Among them, stress minimization produces layouts of comparatively high quality but also imposes comparatively high computational demands. We propose a speed-up method based on the aggregation of terms in the objective function. It is akin to aggregate repulsion from far-away nodes during spring embedding but transfers the idea from the layout space into a preprocessing phase. An initial experimental study informs a method to select representatives, and subsequent more extensive experiments indicate that our method yields better approximations of minimum-stress layouts in less time than related methods.Comment: Appears in the Proceedings of the 24th International Symposium on Graph Drawing and Network Visualization (GD 2016

The challenge of developing Special Economic Zones in Africa: evidence and lessons learnt

Special economic zones (SEZs) are mushrooming across the developing world. Increasingly, policymakers resort to zones with the aim of turning around their countries’ economic fortunes. Zones are expected to deliver greater innovation, exports, knowledge and technological spillovers. Yet, little is known about the state of play of SEZs in Africa, where almost half of SEZ programmes are less than 10 years old. The recent proliferation of SEZs in the continent has rendered the need to ensure that SEZs deliver on their objectives more impelling, given the often non-negligible opportunity costs associated with SEZ development. This article addresses this knowledge gap and sheds light on African SEZ practices. The analysis of a novel dataset highlights that (i) African SEZs are on a steep upward trend and are changing in nature; (ii) the ability of African SEZs to attract industrial activity, proxied by firms, and generate employment remains limited; and (iii) African SEZ governance policies (over)rely on fiscal incentives and performance requirements. Case studies from Ethiopia, Morocco and South Africa suggest that those African SEZ programmes that have a well-targeted strategic focus, promote institutional collaboration and take a proactive approach to create linkages with the local economy are more likely to succeed

WEXTOR: A Web-based tool for generating and visualizing experimental designs and procedures

WEXTOR is a Javascript-based experiment generator and teaching tool on the World-Wide Web that can be used to design laboratory and Web experiments in a guided step-by-step process. It dynamically creates the customized Web pages and Javascripts needed for the experimental procedure and provides experimenters with a print-ready visual display of their experimental design. WEXTOR flexibly supports complete and incomplete factorial designs with between-subjects, within-subjects, and quasiexperimental factors, as well as mixed designs. The software implements client-side response time measurement and contains a content wizard for creating interactive materials, as well as dependent measures (graphical scales, multiple-choice items, etc.), on the experiment pages. However, it does not aim to replace a full-fledged HTML editor. Several methodological features specifically needed in Web experimental design have been implemented in the Web-based tool and are described in this paper. WEXTOR is platform independent. The created Web pages can be uploaded to any type of Web server in which data may be recorded in logfiles or via a database. The current version of WEXTOR is freely available for educational and noncommercial purposes. Its Web address is http://www.genpsylab.unizh.ch/wextor/index.html

Resilient Placement of VNFs and Distributed MANO Components in a WMN-based NFV Infrastructure

Wireless Multi-Radio Outdoor-Routers are building a Wireless Mesh Network (WMN), which is used as an emergency communication infrastructure in case a disaster destroyed the existing communication system. A dynamic service provisioning shall be achieved by integrating Network Function Virtualisation (NFV) into the network. A distributed management and orchestration (MANO), which operates in-band of the network, controls the NFV infrastructure (NFVI). The primary goal of the distributed MANO consists of improving the network resilience to changes affecting the NFVI, namely node and link failures. For this aspect, the position of the Virtual Network Functions (VNFs), implementing a functional service component, as well as the position of the components building the distributed MANO within the WMN-based NFVI is essential. For this purpose, this publication proposes a concept for the resilient placement of the VNFs and distributed MANO components required within the WMN-based NFVI. Furthermore, a mathematical model of the network and an Integer Linear Programming (ILP) based optimisation target for implementing the concept are proposed. The optimisation target considers the connectivity of NFVI-Nodes at the placement by preferring well-connected NFVI-Nodes and avoiding poorly-connected ones. If required due to limited hardware resources, priorities among the different kinds of network functions are considered. Multiple existing solvers are used on the optimisation target to evaluate their performance in terms of their required time for providing an optimal solution based on different network sizes

The RNA helicase database

RNA helicases are ubiquitous and essential enzymes that function in nearly all aspects of RNA metabolism. The RNA helicase database (www.rnahelicase.org) integrates the wealth of accumulating information on RNA helicases in a readily accessible format. The database is a portal that allows straightforward retrieval of comprehensive information on sequence, structure and on biochemical and cellular functions of all RNA helicases from the most widely used model organisms Escherichia coli, Saccharomyces cerevisiae, Caenorhabditis elegans, Drosophila melanogaster, mouse and human. Also included are RNA helicases from other organisms that are subject to specific investigation. The database is structured according to the most recent helicase classification into helicase superfamilies (SFs) and families, and thus emphasizes phyologenetic relations between RNA helicases as well. Information on individual RNA helicases can be accessed through various browsing routes or through text-based searches of the database