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Very Different Types (very + different_type)
Selected AbstractsEurope at the MillenniumPOLITICS, Issue 2 2000Mary Kaldor This article argues that the future of the European project depends on the capacity to maintain security. It traces the link between security and political institutions in the case of nation states and, subsequently, blocs. The security of nation states and blocs was defined in terms of the defence of borders against an external enemy and the preservation of law and order within borders. Today, the distinction between internal and external has broken down; ,new wars' are a mixture of war, organised crime and violations of human rights. Security can only be maintained through the extension of law and order beyond borders , through enlargement, migration and citizenship policies, and effective humanitarian intervention. Any other approach could lead to a reversal of the process of integration. This type of security policy is likely to be associated with a very different type of polity. [source] ON THE EVOLUTION OF HARMING AND RECOGNITION IN FINITE PANMICTIC AND INFINITE STRUCTURED POPULATIONSEVOLUTION, Issue 11 2009Laurent Lehmann Natural selection may favor two very different types of social behaviors that have costs in vital rates (fecundity and/or survival) to the actor: helping behaviors, which increase the vital rates of recipients, and harming behaviors, which reduce the vital rates of recipients. Although social evolutionary theory has mainly dealt with helping behaviors, competition for limited resources creates ecological conditions in which an actor may benefit from expressing behaviors that reduce the vital rates of neighbors. This may occur if the reduction in vital rates decreases the intensity of competition experienced by the actor or that experienced by its offspring. Here, we explore the joint evolution of neutral recognition markers and marker-based costly conditional harming whereby actors express harming, conditional on actor and recipient bearing different conspicuous markers. We do so for two complementary demographic scenarios: finite panmictic and infinite structured populations. We find that marker-based conditional harming can evolve under a large range of recombination rates and group sizes under both finite panmictic and infinite structured populations. A direct comparison with results for the evolution of marker-based conditional helping reveals that, if everything else is equal, marker-based conditional harming is often more likely to evolve than marker-based conditional helping. [source] Too hot to handle?JOURNAL OF SYNCHROTRON RADIATION, Issue 6 2002Synchrotron X-ray damage of lipid membranes, mesophases The call for brighter synchrotron X-radiation sources for use in structural biology research is barely audible as we enter the new millennium. Our brightest sources are already creating havoc when used at design specifications because of radiation damage. The time is long overdue to take stock of where we are and where we wish to go with regards to using existing sources and to designing new ones. The problem of radiation damage is particularly acute in studies involving kinetics and mechanisms where cryo-techniques are not always viable. Accordingly, we need to understand the very nature of radiation damage and to devise means of minimizing it. This is the thrust of the current report as applied to lipid membranes and mesophases. The experiments were performed at the most brilliant beamlines at CHESS, the APS and the ESRF. Two very different types of radiation damage are reported here. One involves a dramatic phase transformation and the other a disordering of lamellar stacking. How beam energy and dose rate affect damage is also discussed. The work highlights the free-radical-mediated nature of the damage process and the need for additional studies if the most efficient use is to be made of an important resource, synchrotron radiation. [source] WICKED WATER PROBLEMS: SOCIOLOGY AND LOCAL WATER ORGANIZATIONS IN ADDRESSING WATER RESOURCES POLICY,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 3 2000David M. Freeman ABSTRACT: Water policy problems are wicked, not in an ethically deplorable sense, but in the sense that they present us with especially difficult challenges of becoming more effective in our interdisciplinary collaboration, of integrating two very different types of knowledge, of working across several socio-political units of analysis simultaneously, and of better organizing water as a common property resource. Sociology, as a discipline, does not have a particularly rich history of successful interdisciplinary collaboration on water resources research and teaching, but it potentially has a most useful contribution to make by focusing on the analysis of local common property resource organizations that operate in the interface between individual resource users and State-Federal entities. These organizations (e.g., water user associations, mutual companies, irrigation districts, acequias, conservancy districts) have been the orphans of water policy discourse but their operations are critical to undertaking more effective 21st century social analysis, research work, and action programs. Sociologists who work to better comprehend the operations of, and constraints upon, these organizations build a sociology that can better collaborate with other water-related disciplines in addressing the challenges posed by the wickedness of our water problems. [source] A novel bacterial signalling system with a combination of a Ser/Thr kinase cascade and a His/Asp two-component systemMOLECULAR MICROBIOLOGY, Issue 2 2005Renate Lux Summary Prokaryotes and eukaryotes have long been thought to use very different types of kinases (the His kinases of the ,bacterial' two-component systems versus the ,eukaryotic' Ser/Thr/Tyr kinases) to carry out signal transduction. This paradigm no longer holds true, because both systems are now found together in an increasing number of prokaryotic organisms and ,two-component' His kinase are present in eukaryotes. Pioneering work on bacterial protein serine threonine kinases (PSTKs) has been performed in Myxococcus xanthus, a soil bacterium with a complex life cycle that possesses orthologues of signalling-related kinases ,typical' of both the prokaryotic and the eukaryotic kingdoms. In the work reported in this volume of Molecular Microbiology, Nariya and Inouye describe a PSTK cascade that modulates the biochemical activity of MrpC, a CRP-like transcriptional regulator for essential developmental signalling pathways in M. xanthus whose transcription is under the control of a two-component system. This is the first report of both a functional PSTK cascade in bacteria and the use of both PSTK and two-component systems to control a single complex bacterial signalling event. [source] | ||||||||||