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Selected AbstractsNaturalization and invasion of alien plants: concepts and definitionsDIVERSITY AND DISTRIBUTIONS, Issue 2 2000David M. Richardson Abstract., Much confusion exists in the English-language literature on plant invasions concerning the terms ,naturalized' and ,invasive' and their associated concepts. Several authors have used these terms in proposing schemes for conceptualizing the sequence of events from introduction to invasion, but often imprecisely, erroneously or in contradictory ways. This greatly complicates the formulation of robust generalizations in invasion ecology. Based on an extensive and critical survey of the literature we defined a minimum set of key terms related to a graphic scheme which conceptualizes the naturalization/invasion process. Introduction means that the plant (or its propagule) has been transported by humans across a major geographical barrier. Naturalization starts when abiotic and biotic barriers to survival are surmounted and when various barriers to regular reproduction are overcome. Invasion further requires that introduced plants produce reproductive offspring in areas distant from sites of introduction (approximate scales: > 100 m over < 50 years for taxa spreading by seeds and other propagules; > 6 m/3 years for taxa spreading by roots, rhizomes, stolons or creeping stems). Taxa that can cope with the abiotic environment and biota in the general area may invade disturbed, seminatural communities. Invasion of successionally mature, undisturbed communities usually requires that the alien taxon overcomes a different category of barriers. We propose that the term ,invasive' should be used without any inference to environmental or economic impact. Terms like ,pests' and ,weeds' are suitable labels for the 50,80% of invaders that have harmful effects. About 10% of invasive plants that change the character, condition, form, or nature of ecosystems over substantial areas may be termed ,transformers'. [source] From gene amplification to V(D)J recombination and back: A personal account of my early years in B cell biologyEUROPEAN JOURNAL OF IMMUNOLOGY, Issue S1 2007Frederick Abstract I have been invited to write a short historical feature in the context of being a co-recipient with Klaus Rajewsky and Fritz Melchers of the 2007,Novartis Prize in Basic Immunology that was given in the general area of the molecular biology of B cells. In this feature, I cover the main points of the short talk that I presented at the Award Ceremony at the International Immunology Congress in Rio de Janeiro, Brazil. This talk focused primarily on the work and people involved early on in generating the models and ideas that have formed the basis for my ongoing efforts in the areas of V(D)J recombination and B cell development. [source] Spitzer IRAC infrared colours of submillimetre-bright galaxiesMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 1 2008Min S. Yun ABSTRACT High-redshift submillimetre-bright galaxies identified by blank field surveys at millimetre and submillimetre wavelengths appear in the region of the Infra Red Array Camera (IRAC) colour,colour diagrams previously identified as the domain of luminous active galactic nuclei (AGNs). Our analysis using a set of empirical and theoretical dusty starburst spectral energy distribution (SED) models shows that power-law continuum sources associated with hot dust heated by young (,100 Myr old), extreme starbursts at z > 2 also occupy the same general area as AGNs in the IRAC colour,colour plots. A detailed comparison of the IRAC colours and SEDs demonstrates that the two populations are distinct from each other, with submillimetre-bright galaxies having a systematically flatter IRAC spectrum (,1 mag bluer in the observed [4.5],[8.0] colour). Only about 20 per cent of the objects overlap in the colour,colour plots, and this low fraction suggests that submillimetre galaxies powered by a dust-obscured AGN are not common. The red infrared colours of the submillimetre galaxies are distinct from those of the ubiquitous foreground IRAC sources, and we propose a set of infrared colour selection criteria for identifying SMG counterparts that can be used even in the absence of radio or Multiband Imaging Photometer for Spitzer (MIPS) 24 ,m data. [source] Time Series Concepts for Conditional Distributions*OXFORD BULLETIN OF ECONOMICS & STATISTICS, Issue 2003Clive W. J. Granger Abstract The paper asks the question , as time series analysis moves from consideration of conditional mean values and variances to unconditional distributions, do some of the familiar concepts devised for the first two moments continue to be helpful in the more general area? Most seem to generalize fairly easy, such as the concepts of breaks, seasonality, trends and regime switching. Forecasting is more difficult, as forecasts become distributions, as do forecast errors. Persistence can be defined and also common factors by using the idea of a copula. Aggregation is more difficult but causality and controllability can be defined. The study of the time series of quantiles becomes more relevant. [source] Electro-Thermal Dynamic Stripping Process for in situ remediation under an occupied apartment buildingREMEDIATION, Issue 3 2003Bruce C.W. McGee The implementation and performance results of the Electro-Thermal Dynamic Stripping Process (ET-DSPÔ) used in combination with high-vacuum dual-phase extraction are presented here. The technology was selected to remove vapor pressure-sensitive benzene, toluene, ethyl benzene, and xylene (BTEX) compounds from under an occupied residential apartment building. Operating within several engineering, environmental, and safety constraints, a design was developed to conduct electrical heating and in situ extraction operations without disruption of the daily activities of the residents within the apartment complex and general area. The results consistently showed a significant reduction in the concentration of hydrocarbons with non-detectable levels being achieved in all of the samples that were tested. This is a direct result of a substantial temperature increase of the soil and concurrent increase in the hydrocarbon vapor pressure from the ET-DSPÔ system. © 2003 Wiley Periodicals, Inc. [source] Drug Policy and the Public Good: a summary of the bookADDICTION, Issue 7 2010Drugs, Public Policy Group ABSTRACT Drug Policy and the Public Good was written by an international group of scientists from the fields of addiction, public health, criminology and policy studies to improve the linkages between drug research and drug policy. The book provides a conceptual basis for evidence-informed drug policy and describes epidemiological data on the global dimensions of drug misuse. The core of the book is a critical review of the cumulative scientific evidence in five general areas of drug policy: primary prevention programmes in schools and other settings; health and social services for drug users; attempts to control the supply of drugs, including the international treaty system; law enforcement and ventures into decriminalization; and control of the psychotropic substance market through prescription drug regimes. The final chapters discuss the current state of drug policies in different parts of the world and describe the need for future approaches to drug policy that are coordinated and informed by evidence. [source] A survey of the year 2002 literature on applications of isothermal titration calorimetryJOURNAL OF MOLECULAR RECOGNITION, Issue 6 2003Matthew J. Cliff Abstract Isothermal titration calorimetry (ITC) is becoming widely accepted as a key instrument in any laboratory in which quantification of biomolecular interactions is a requisite. The method has matured with respect to general acceptance and application development over recent years. The number of publications on ITC has grown exponentially over the last 10 years, reflecting the general utility of the method. Here all the published works of the year 2002 in this area have been surveyed. We review the broad range of systems to which ITC is being directed and classify these into general areas highlighting key publications of interest. This provides an overview of what can be achieved using this method and what developments are likely to occur in the near future. Copyright © 2003 John Wiley & Sons, Ltd. [source] Chemistry and technology of 2-alkenyl azlactonesJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 21 2001Steven M. Heilmann Abstract The chronology of 2-alkenyl azlactone research at 3M is discussed in terms of its origination; consideration of economics, overall safety, and opportunities for patent protection; elaboration of the chemistry; and, finally, applying lessons learned toward the development of commercial technologies. The chemistry is dominated by the presence of three electrophilic reaction centers and a readily polymerizable 2-alkenyl group. Technological development has been focused in four general areas: acrylamide monomers, acrylamide materials, azlactone materials, and polymer modification. Application areas disinclude lithographic printing plates, contact lens materials, adhesives, dispersants for printing inks, and supports for immobilizing enzymes. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3655,3677, 2001 [source] | ||||||||||